hw/sensor: Add SB-TSI Temperature Sensor Interface

Commit Message

Patrick Leis Jan. 8, 2022, 3:04 a.m. UTC

From: Hao Wu <[e-mail]>

SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
interface that reports AMD SoC's Ttcl (normalized temperature),
and resembles a typical 8-pin remote temperature sensor's I2C interface
to BMC.

This patch implements a basic AMD SB-TSI sensor that is
compatible with the open-source data sheet from AMD and Linux
kernel driver.

Reference:
Linux kernel driver:
https://lkml.org/lkml/2020/12/11/968
Register Map:
https://developer.amd.com/wp-content/resources/56255_3_03.PDF
(Chapter 6)

Signed-off-by: Hao Wu <[e-mail]>
Reviewed-by: Doug Evans <[e-mail]>
---
 hw/sensor/Kconfig            |   4 +
 hw/sensor/meson.build        |   1 +
 hw/sensor/tmp_sbtsi.c        | 393 +++++++++++++++++++++++++++++++++++
 hw/sensor/trace-events       |   5 +
 hw/sensor/trace.h            |   1 +
 meson.build                  |   1 +
 tests/qtest/meson.build      |   1 +
 tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++
 8 files changed, 586 insertions(+)
 create mode 100644 hw/sensor/tmp_sbtsi.c
 create mode 100644 hw/sensor/trace-events
 create mode 100644 hw/sensor/trace.h
 create mode 100644 tests/qtest/tmp_sbtsi-test.c

Comments

Patrick Leis Jan. 10, 2022, 2:17 a.m. UTC | #1

On Fri, Jan 7, 2022 at 7:04 PM Patrick Venture <[e-mail]> wrote:

> From: Hao Wu <[e-mail]>
>
> SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
> interface that reports AMD SoC's Ttcl (normalized temperature),
> and resembles a typical 8-pin remote temperature sensor's I2C interface
> to BMC.
>
> This patch implements a basic AMD SB-TSI sensor that is
> compatible with the open-source data sheet from AMD and Linux
> kernel driver.
>
> Reference:
> Linux kernel driver:
> https://lkml.org/lkml/2020/12/11/968
> Register Map:
> https://developer.amd.com/wp-content/resources/56255_3_03.PDF
> (Chapter 6)
>
> Signed-off-by: Hao Wu <[e-mail]>
> Reviewed-by: Doug Evans <[e-mail]>
> ---
>  hw/sensor/Kconfig            |   4 +
>  hw/sensor/meson.build        |   1 +
>  hw/sensor/tmp_sbtsi.c        | 393 +++++++++++++++++++++++++++++++++++
>  hw/sensor/trace-events       |   5 +
>  hw/sensor/trace.h            |   1 +
>  meson.build                  |   1 +
>  tests/qtest/meson.build      |   1 +
>  tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++
>  8 files changed, 586 insertions(+)
>  create mode 100644 hw/sensor/tmp_sbtsi.c
>  create mode 100644 hw/sensor/trace-events
>  create mode 100644 hw/sensor/trace.h
>  create mode 100644 tests/qtest/tmp_sbtsi-test.c
>
> diff --git a/hw/sensor/Kconfig b/hw/sensor/Kconfig
> index 9c8a049b06..27f6f79c84 100644
> --- a/hw/sensor/Kconfig
> +++ b/hw/sensor/Kconfig
> @@ -21,3 +21,7 @@ config ADM1272
>  config MAX34451
>      bool
>      depends on I2C
> +
> +config AMDSBTSI
> +    bool
> +    depends on I2C
> diff --git a/hw/sensor/meson.build b/hw/sensor/meson.build
> index 059c4ca935..f7b0e645eb 100644
> --- a/hw/sensor/meson.build
> +++ b/hw/sensor/meson.build
> @@ -4,3 +4,4 @@ softmmu_ss.add(when: 'CONFIG_DPS310', if_true:
> files('dps310.c'))
>  softmmu_ss.add(when: 'CONFIG_EMC141X', if_true: files('emc141x.c'))
>  softmmu_ss.add(when: 'CONFIG_ADM1272', if_true: files('adm1272.c'))
>  softmmu_ss.add(when: 'CONFIG_MAX34451', if_true: files('max34451.c'))
> +softmmu_ss.add(when: 'CONFIG_AMDSBTSI', if_true: files('tmp_sbtsi.c'))
> diff --git a/hw/sensor/tmp_sbtsi.c b/hw/sensor/tmp_sbtsi.c
> new file mode 100644
> index 0000000000..b68c7ebf61
> --- /dev/null
> +++ b/hw/sensor/tmp_sbtsi.c
> @@ -0,0 +1,393 @@
> +/*
> + * AMD SBI Temperature Sensor Interface (SB-TSI)
> + *
> + * Copyright 2021 Google LLC
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful, but
> WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
> + * for more details.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "hw/i2c/smbus_slave.h"
> +#include "hw/irq.h"
> +#include "migration/vmstate.h"
> +#include "qapi/error.h"
> +#include "qapi/visitor.h"
> +#include "qemu/log.h"
> +#include "qemu/module.h"
> +#include "trace.h"
> +
> +#define TYPE_SBTSI "sbtsi"
> +#define SBTSI(obj) OBJECT_CHECK(SBTSIState, (obj), TYPE_SBTSI)
> +
> +/**
> + * SBTSIState:
> + * temperatures are in units of 0.125 degrees
> + * @temperature: Temperature
> + * @limit_low: Lowest temperature
> + * @limit_high: Highest temperature
> + * @status: The status register
> + * @config: The config register
> + * @alert_config: The config for alarm_l output.
> + * @addr: The address to read/write for the next cmd.
> + * @alarm: The alarm_l output pin (GPIO)
> + */
> +typedef struct SBTSIState {
> +    SMBusDevice parent;
> +
> +    uint32_t temperature;
> +    uint32_t limit_low;
> +    uint32_t limit_high;
> +    uint8_t status;
> +    uint8_t config;
> +    uint8_t alert_config;
> +    uint8_t addr;
> +    qemu_irq alarm;
> +} SBTSIState;
> +
> +/*
> + * SB-TSI registers only support SMBus byte data access. "_INT" registers
> are
> + * the integer part of a temperature value or limit, and "_DEC" registers
> are
> + * corresponding decimal parts.
> + */
> +#define SBTSI_REG_TEMP_INT      0x01 /* RO */
> +#define SBTSI_REG_STATUS        0x02 /* RO */
> +#define SBTSI_REG_CONFIG        0x03 /* RO */
> +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */
> +#define SBTSI_REG_TEMP_LOW_INT  0x08 /* RW */
> +#define SBTSI_REG_CONFIG_WR     0x09 /* RW */
> +#define SBTSI_REG_TEMP_DEC      0x10 /* RO */
> +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */
> +#define SBTSI_REG_TEMP_LOW_DEC  0x14 /* RW */
> +#define SBTSI_REG_ALERT_CONFIG  0xBF /* RW */
> +#define SBTSI_REG_MAN           0xFE /* RO */
> +#define SBTSI_REG_REV           0xFF /* RO */
> +
> +#define SBTSI_STATUS_HIGH_ALERT BIT(4)
> +#define SBTSI_STATUS_LOW_ALERT  BIT(3)
> +#define SBTSI_CONFIG_ALERT_MASK BIT(7)
> +#define SBTSI_ALARM_EN          BIT(0)
> +
> +#define SBTSI_LIMIT_LOW_DEFAULT (0)
> +#define SBTSI_LIMIT_HIGH_DEFAULT (560)
> +#define SBTSI_MAN_DEFAULT (0)
> +#define SBTSI_REV_DEFAULT (4)
> +#define SBTSI_ALARM_L "alarm_l"
> +
> +/* The temperature we stored are in units of 0.125 degrees. */
> +#define SBTSI_TEMP_UNIT_IN_MILLIDEGREE 125
> +
> +/*
> + * The integer part and decimal of the temperature both 8 bits.
> + * Only the top 3 bits of the decimal parts are used.
> + * So the max temperature is (2^8-1) + (2^3-1)/8 = 255.875 degrees.
> + */
> +#define SBTSI_TEMP_MAX 255875
> +
> +/* The integer part of the temperature in terms of 0.125 degrees. */
> +static uint8_t get_temp_int(uint32_t temp)
> +{
> +    return temp >> 3;
> +}
> +
> +/*
> + * The decimal part of the temperature, in terms of 0.125 degrees.
> + * H/W store it in the top 3 bits so we shift it by 5.
> + */
> +static uint8_t get_temp_dec(uint32_t temp)
> +{
> +    return (temp & 0x7) << 5;
> +}
> +
> +/*
> + * Compute the temperature using the integer and decimal part,
> + * in terms of 0.125 degrees. The decimal part are only the top 3 bits
> + * so we shift it by 5 here.
> + */
> +static uint32_t compute_temp(uint8_t integer, uint8_t decimal)
> +{
> +    return (integer << 3) + (decimal >> 5);
> +}
> +
> +/* Compute new temp with new int part of the temperature. */
> +static uint32_t compute_temp_int(uint32_t temp, uint8_t integer)
> +{
> +    return compute_temp(integer, get_temp_dec(temp));
> +}
> +
> +/* Compute new temp with new dec part of the temperature. */
> +static uint32_t compute_temp_dec(uint32_t temp, uint8_t decimal)
> +{
> +    return compute_temp(get_temp_int(temp), decimal);
> +}
> +
> +/* The integer part of the temperature. */
> +static void sbtsi_update_status(SBTSIState *s)
> +{
> +    s->status = 0;
> +    if (s->alert_config & SBTSI_ALARM_EN) {
> +        if (s->temperature >= s->limit_high) {
> +            s->status |= SBTSI_STATUS_HIGH_ALERT;
> +        }
> +        if (s->temperature <= s->limit_low) {
> +            s->status |= SBTSI_STATUS_LOW_ALERT;
> +        }
> +    }
> +}
> +
> +static void sbtsi_update_alarm(SBTSIState *s)
> +{
> +    sbtsi_update_status(s);
> +    if (s->status != 0 && !(s->config & SBTSI_CONFIG_ALERT_MASK)) {
> +        qemu_irq_raise(s->alarm);
> +    } else {
> +        qemu_irq_lower(s->alarm);
> +    }
> +}
> +
> +static uint8_t sbtsi_read_byte(SMBusDevice *d)
> +{
> +    SBTSIState *s = SBTSI(d);
> +    uint8_t data = 0;
> +
> +    switch (s->addr) {
> +    case SBTSI_REG_TEMP_INT:
> +        data = get_temp_int(s->temperature);
> +        break;
> +
> +    case SBTSI_REG_TEMP_DEC:
> +        data = get_temp_dec(s->temperature);
> +        break;
> +
> +    case SBTSI_REG_TEMP_HIGH_INT:
> +        data = get_temp_int(s->limit_high);
> +        break;
> +
> +    case SBTSI_REG_TEMP_LOW_INT:
> +        data = get_temp_int(s->limit_low);
> +        break;
> +
> +    case SBTSI_REG_TEMP_HIGH_DEC:
> +        data = get_temp_dec(s->limit_high);
> +        break;
> +
> +    case SBTSI_REG_TEMP_LOW_DEC:
> +        data = get_temp_dec(s->limit_low);
> +        break;
> +
> +    case SBTSI_REG_CONFIG:
> +    case SBTSI_REG_CONFIG_WR:
> +        data = s->config;
> +        break;
> +
> +    case SBTSI_REG_STATUS:
> +        sbtsi_update_alarm(s);
> +        data = s->status;
> +        break;
> +
> +    case SBTSI_REG_ALERT_CONFIG:
> +        data = s->alert_config;
> +        break;
> +
> +    case SBTSI_REG_MAN:
> +        data = SBTSI_MAN_DEFAULT;
> +        break;
> +
> +    case SBTSI_REG_REV:
> +        data = SBTSI_REV_DEFAULT;
> +        break;
> +
> +    default:
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                "%s: reading from invalid reg: 0x%02x\n",
> +                __func__, s->addr);
> +        break;
> +    }
> +
> +    trace_tmp_sbtsi_read_data(s->addr, data);
> +    return data;
> +}
> +
> +static void sbtsi_write(SBTSIState *s, uint8_t data)
> +{
> +    trace_tmp_sbtsi_write_data(s->addr, data);
> +    switch (s->addr) {
> +    case SBTSI_REG_CONFIG_WR:
> +        s->config = data;
> +        break;
> +
> +    case SBTSI_REG_TEMP_HIGH_INT:
> +        s->limit_high = compute_temp_int(s->limit_high, data);
> +        break;
> +
> +    case SBTSI_REG_TEMP_LOW_INT:
> +        s->limit_low = compute_temp_int(s->limit_low, data);
> +        break;
> +
> +    case SBTSI_REG_TEMP_HIGH_DEC:
> +        s->limit_high = compute_temp_dec(s->limit_high, data);
> +        break;
> +
> +    case SBTSI_REG_TEMP_LOW_DEC:
> +        s->limit_low = compute_temp_dec(s->limit_low, data);
> +        break;
> +
> +    case SBTSI_REG_ALERT_CONFIG:
> +        s->alert_config = data;
> +        break;
> +
> +    case SBTSI_REG_TEMP_INT:
> +    case SBTSI_REG_TEMP_DEC:
> +    case SBTSI_REG_CONFIG:
> +    case SBTSI_REG_STATUS:
> +    case SBTSI_REG_MAN:
> +    case SBTSI_REG_REV:
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                "%s: writing to read only reg: 0x%02x data: 0x%02x\n",
> +                __func__, s->addr, data);
> +        break;
> +
> +    default:
> +        qemu_log_mask(LOG_GUEST_ERROR,
> +                "%s: writing to invalid reg: 0x%02x data: 0x%02x\n",
> +                __func__, s->addr, data);
> +        break;
> +    }
> +    sbtsi_update_alarm(s);
> +}
> +
> +static int sbtsi_write_data(SMBusDevice *d, uint8_t *buf, uint8_t len)
> +{
> +    SBTSIState *s = SBTSI(d);
> +
> +    if (len == 0) {
> +        qemu_log_mask(LOG_GUEST_ERROR, "%s: writing empty data\n",
> __func__);
> +        return -1;
> +    }
> +
> +    s->addr = buf[0];
> +    if (len > 1) {
> +        sbtsi_write(s, buf[1]);
> +        if (len > 2) {
> +            qemu_log_mask(LOG_GUEST_ERROR, "%s: extra data at end\n",
> __func__);
> +        }
> +    }
> +    return 0;
> +}
> +
> +/* Units are millidegrees. */
> +static void sbtsi_get_temperature(Object *obj, Visitor *v, const char
> *name,
> +                                  void *opaque, Error **errp)
> +{
> +    SBTSIState *s = SBTSI(obj);
> +    uint32_t temp = s->temperature * SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
> +
> +    visit_type_uint32(v, name, &temp, errp);
> +}
> +
> +/* Units are millidegrees. */
> +static void sbtsi_set_temperature(Object *obj, Visitor *v, const char
> *name,
> +                                  void *opaque, Error **errp)
> +{
> +    SBTSIState *s = SBTSI(obj);
> +    uint32_t temp;
> +
> +    if (!visit_type_uint32(v, name, &temp, errp)) {
> +        return;
> +    }
> +    if (temp > SBTSI_TEMP_MAX) {
> +        error_setg(errp, "value %" PRIu32 ".%03" PRIu32 " C is out of
> range",
> +                   temp / 1000, temp % 1000);
> +        return;
> +    }
> +
> +    s->temperature = temp / SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
> +    sbtsi_update_alarm(s);
> +}
> +
> +static int sbtsi_post_load(void *opaque, int version_id)
> +{
> +    SBTSIState *s = opaque;
> +
> +    sbtsi_update_alarm(s);
> +    return 0;
> +}
> +
> +static const VMStateDescription vmstate_sbtsi = {
> +    .name = "SBTSI",
> +    .version_id = 0,
> +    .minimum_version_id = 0,
> +    .post_load = sbtsi_post_load,
> +    .fields = (VMStateField[]) {
> +        VMSTATE_UINT32(temperature, SBTSIState),
> +        VMSTATE_UINT32(limit_low, SBTSIState),
> +        VMSTATE_UINT32(limit_high, SBTSIState),
> +        VMSTATE_UINT8(config, SBTSIState),
> +        VMSTATE_UINT8(status, SBTSIState),
> +        VMSTATE_UINT8(addr, SBTSIState),
> +        VMSTATE_END_OF_LIST()
> +    }
> +};
> +
> +static void sbtsi_enter_reset(Object *obj, ResetType type)
> +{
> +    SBTSIState *s = SBTSI(obj);
> +
> +    s->config = 0;
> +    s->limit_low = SBTSI_LIMIT_LOW_DEFAULT;
> +    s->limit_high = SBTSI_LIMIT_HIGH_DEFAULT;
> +}
> +
> +static void sbtsi_hold_reset(Object *obj)
> +{
> +    SBTSIState *s = SBTSI(obj);
> +
> +    qemu_irq_lower(s->alarm);
> +}
> +
> +static void sbtsi_init(Object *obj)
> +{
> +    SBTSIState *s = SBTSI(obj);
> +
> +    /* Current temperature in millidegrees. */
> +    object_property_add(obj, "temperature", "uint32",
> +                        sbtsi_get_temperature, sbtsi_set_temperature,
> +                        NULL, NULL);
> +    qdev_init_gpio_out_named(DEVICE(obj), &s->alarm, SBTSI_ALARM_L, 0);
> +}
> +
> +static void sbtsi_class_init(ObjectClass *klass, void *data)
> +{
> +    ResettableClass *rc = RESETTABLE_CLASS(klass);
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    SMBusDeviceClass *k = SMBUS_DEVICE_CLASS(klass);
> +
> +    dc->desc = "SB-TSI Temperature Sensor";
> +    dc->vmsd = &vmstate_sbtsi;
> +    k->write_data = sbtsi_write_data;
> +    k->receive_byte = sbtsi_read_byte;
> +    rc->phases.enter = sbtsi_enter_reset;
> +    rc->phases.hold = sbtsi_hold_reset;
> +}
> +
> +static const TypeInfo sbtsi_info = {
> +    .name          = TYPE_SBTSI,
> +    .parent        = TYPE_SMBUS_DEVICE,
> +    .instance_size = sizeof(SBTSIState),
> +    .instance_init = sbtsi_init,
> +    .class_init    = sbtsi_class_init,
> +};
> +
> +static void sbtsi_register_types(void)
> +{
> +    type_register_static(&sbtsi_info);
> +}
> +
> +type_init(sbtsi_register_types)
> diff --git a/hw/sensor/trace-events b/hw/sensor/trace-events
> new file mode 100644
> index 0000000000..21ab3809e2
> --- /dev/null
> +++ b/hw/sensor/trace-events
> @@ -0,0 +1,5 @@
> +# See docs/devel/tracing.rst for syntax documentation.
> +
> +# tmp_sbtsi.c
> +tmp_sbtsi_write_data(uint8_t addr, uint8_t value) "SBTSI write
> addr:0x%02x data: 0x%02x"
> +tmp_sbtsi_read_data(uint8_t addr, uint8_t value) "SBTSI read addr:0x%02x
> data: 0x%02x"
> diff --git a/hw/sensor/trace.h b/hw/sensor/trace.h
> new file mode 100644
> index 0000000000..e4721560b0
> --- /dev/null
> +++ b/hw/sensor/trace.h
> @@ -0,0 +1 @@
> +#include "trace/trace-hw_sensor.h"
> diff --git a/meson.build b/meson.build
> index 53065e96ec..f8ab0bf74e 100644
> --- a/meson.build
> +++ b/meson.build
> @@ -2494,6 +2494,7 @@ if have_system
>      'hw/rtc',
>      'hw/s390x',
>      'hw/scsi',
> +    'hw/sensor',
>      'hw/sd',
>      'hw/sh4',
>      'hw/sparc',
> diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
> index 37e1eaa449..d1a8c38f74 100644
> --- a/tests/qtest/meson.build
> +++ b/tests/qtest/meson.build
> @@ -254,6 +254,7 @@ qos_test_ss.add(
>    'spapr-phb-test.c',
>    'tmp105-test.c',
>    'emc141x-test.c',
> +  'tmp_sbtsi-test.c',
>    'usb-hcd-ohci-test.c',
>    'virtio-test.c',
>    'virtio-blk-test.c',
> diff --git a/tests/qtest/tmp_sbtsi-test.c b/tests/qtest/tmp_sbtsi-test.c
> new file mode 100644
> index 0000000000..7f5fafacc7
> --- /dev/null
> +++ b/tests/qtest/tmp_sbtsi-test.c
> @@ -0,0 +1,180 @@
> +/*
> + * QTests for the SBTSI temperature sensor
> + *
> + * Copyright 2020 Google LLC
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful, but
> WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
> + * for more details.
> + */
> +
> +#include "qemu/osdep.h"
> +
> +#include "libqtest-single.h"
> +#include "libqos/qgraph.h"
> +#include "libqos/i2c.h"
> +#include "qapi/qmp/qdict.h"
> +#include "qemu/bitops.h"
> +
> +#define TEST_ID   "sbtsi-test"
> +#define TEST_ADDR (0x4c)
> +
> +/*
> + * SB-TSI registers only support SMBus byte data access. "_INT" registers
> are
> + * the integer part of a temperature value or limit, and "_DEC" registers
> are
> + * corresponding decimal parts.
> + */
> +#define REG_TEMP_INT      0x01 /* RO */
> +#define REG_STATUS        0x02 /* RO */
> +#define REG_CONFIG        0x03 /* RO */
> +#define REG_TEMP_HIGH_INT 0x07 /* RW */
> +#define REG_TEMP_LOW_INT  0x08 /* RW */
> +#define REG_CONFIG_WR     0x09 /* RW */
> +#define REG_TEMP_DEC      0x10 /* RO */
> +#define REG_TEMP_HIGH_DEC 0x13 /* RW */
> +#define REG_TEMP_LOW_DEC  0x14 /* RW */
> +#define REG_ALERT_CONFIG  0xBF /* RW */
> +
> +#define STATUS_HIGH_ALERT BIT(4)
> +#define STATUS_LOW_ALERT  BIT(3)
> +#define CONFIG_ALERT_MASK BIT(7)
> +#define ALARM_EN          BIT(0)
> +
> +/* The temperature stored are in units of 0.125 degrees. */
> +#define TEMP_UNIT_IN_MILLIDEGREE 125
> +#define LIMIT_LOW (10500)
> +#define LIMIT_HIGH (55125)
> +
> +static uint32_t qmp_sbtsi_get_temperature(const char *id)
> +{
> +    QDict *response;
> +    int ret;
> +
> +    response = qmp("{ 'execute': 'qom-get', 'arguments': { 'path': %s, "
> +                   "'property': 'temperature' } }", id);
> +    g_assert(qdict_haskey(response, "return"));
> +    ret = (uint32_t)qdict_get_int(response, "return");
> +    qobject_unref(response);
> +    return ret;
> +}
> +
> +static void qmp_sbtsi_set_temperature(const char *id, uint32_t value)
> +{
> +    QDict *response;
> +
> +    response = qmp("{ 'execute': 'qom-set', 'arguments': { 'path': %s, "
> +                   "'property': 'temperature', 'value': %d } }", id,
> value);
> +    g_assert(qdict_haskey(response, "return"));
> +    qobject_unref(response);
> +}
> +
> +/*
> + * Compute the temperature using the integer and decimal part and return
> + * millidegrees. The decimal part are only the top 3 bits so we shift it
> by
> + * 5 here.
> + */
> +static uint32_t regs_to_temp(uint8_t integer, uint8_t decimal)
> +{
> +    return ((integer << 3) + (decimal >> 5)) * TEMP_UNIT_IN_MILLIDEGREE;
> +}
> +
> +/*
> + * Compute the integer and decimal parts of the temperature in
> millidegrees.
> + * H/W store the decimal in the top 3 bits so we shift it by 5.
> + */
> +static void temp_to_regs(uint32_t temp, uint8_t *integer, uint8_t
> *decimal)
> +{
> +    temp /= TEMP_UNIT_IN_MILLIDEGREE;
> +    *integer = temp >> 3;
> +    *decimal = (temp & 0x7) << 5;
> +}
> +
> +static void tx_rx(void *obj, void *data, QGuestAllocator *alloc)
> +{
> +    uint16_t value;
> +    uint8_t integer, decimal;
> +    QI2CDevice *i2cdev = (QI2CDevice *)obj;
> +
> +    /* Test default values */
> +    value = qmp_sbtsi_get_temperature(TEST_ID);
> +    g_assert_cmpuint(value, ==, 0);
> +
> +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
> +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
> +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 0);
> +
> +    /* Test setting temperature */
> +    qmp_sbtsi_set_temperature(TEST_ID, 20000);
> +    value = qmp_sbtsi_get_temperature(TEST_ID);
> +    g_assert_cmpuint(value, ==, 20000);
> +
> +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
> +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
> +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 20000);
> +
> +    /* Set alert mask in config */
> +    i2c_set8(i2cdev, REG_CONFIG_WR, CONFIG_ALERT_MASK);
> +    value = i2c_get8(i2cdev, REG_CONFIG);
> +    g_assert_cmphex(value, ==, CONFIG_ALERT_MASK);
> +    /* Enable alarm_en */
> +    i2c_set8(i2cdev, REG_ALERT_CONFIG, ALARM_EN);
> +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
> +    g_assert_cmphex(value, ==, ALARM_EN);
> +
> +    /* Test setting limits */
> +    /* Limit low = 10.500 */
> +    temp_to_regs(LIMIT_LOW, &integer, &decimal);
> +    i2c_set8(i2cdev, REG_TEMP_LOW_INT, integer);
> +    i2c_set8(i2cdev, REG_TEMP_LOW_DEC, decimal);
> +    integer = i2c_get8(i2cdev, REG_TEMP_LOW_INT);
> +    decimal = i2c_get8(i2cdev, REG_TEMP_LOW_DEC);
> +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, LIMIT_LOW);
> +    /* Limit high = 55.125 */
> +    temp_to_regs(LIMIT_HIGH, &integer, &decimal);
> +    i2c_set8(i2cdev, REG_TEMP_HIGH_INT, integer);
> +    i2c_set8(i2cdev, REG_TEMP_HIGH_DEC, decimal);
> +    integer = i2c_get8(i2cdev, REG_TEMP_HIGH_INT);
> +    decimal = i2c_get8(i2cdev, REG_TEMP_HIGH_DEC);
> +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, LIMIT_HIGH);
> +    /* No alert is generated. */
> +    value = i2c_get8(i2cdev, REG_STATUS);
> +    g_assert_cmphex(value, ==, 0);
> +
> +    /* Test alert for low temperature */
> +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_LOW);
> +    value = i2c_get8(i2cdev, REG_STATUS);
> +    g_assert_cmphex(value, ==, STATUS_LOW_ALERT);
> +
> +    /* Test alert for high temperature */
> +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_HIGH);
> +    value = i2c_get8(i2cdev, REG_STATUS);
> +    g_assert_cmphex(value, ==, STATUS_HIGH_ALERT);
> +
> +    /* Disable alarm_en */
> +    i2c_set8(i2cdev, REG_ALERT_CONFIG, 0);
> +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
> +    g_assert_cmphex(value, ==, 0);
> +    /* No alert when alarm_en is false. */
> +    value = i2c_get8(i2cdev, REG_STATUS);
> +    g_assert_cmphex(value, ==, 0);
> +}
> +
> +static void sbtsi_register_nodes(void)
> +{
> +    QOSGraphEdgeOptions opts = {
> +        .extra_device_opts = "id=" TEST_ID ",address=0x4c"
> +    };
> +    add_qi2c_address(&opts, &(QI2CAddress) { TEST_ADDR });
> +
> +    qos_node_create_driver("sbtsi", i2c_device_create);
> +    qos_node_consumes("sbtsi", "i2c-bus", &opts);
> +
> +    qos_add_test("tx-rx", "sbtsi", tx_rx, NULL);
> +}
> +libqos_init(sbtsi_register_nodes);
> --


+ Corey for i2c maintainer.  The new sensor directory is mostly if not
entirely i2c devices.  I didn't create a maintainer entry for this i2c
device, but I can if desired and send out a v2.


> 2.34.1.575.g55b058a8bb-goog
>
>

Philippe Mathieu-Daudé Jan. 10, 2022, 9:35 a.m. UTC | #2

Hi Patrick,

On 1/8/22 04:04, Patrick Venture wrote:
> From: Hao Wu <[e-mail]>
> 
> SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
> interface that reports AMD SoC's Ttcl (normalized temperature),
> and resembles a typical 8-pin remote temperature sensor's I2C interface
> to BMC.
> 
> This patch implements a basic AMD SB-TSI sensor that is
> compatible with the open-source data sheet from AMD and Linux
> kernel driver.
> 
> Reference:
> Linux kernel driver:
> https://lkml.org/lkml/2020/12/11/968
> Register Map:
> https://developer.amd.com/wp-content/resources/56255_3_03.PDF
> (Chapter 6)
> 
> Signed-off-by: Hao Wu <[e-mail]>
> Reviewed-by: Doug Evans <[e-mail]>
> ---
>  hw/sensor/Kconfig            |   4 +
>  hw/sensor/meson.build        |   1 +
>  hw/sensor/tmp_sbtsi.c        | 393 +++++++++++++++++++++++++++++++++++
>  hw/sensor/trace-events       |   5 +
>  hw/sensor/trace.h            |   1 +
>  meson.build                  |   1 +

>  tests/qtest/meson.build      |   1 +
>  tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++

Up to Thomas for qtest, but I'd rather split in 2 patches since
different set of maintainers / reviewers.

> +++ b/hw/sensor/tmp_sbtsi.c
> @@ -0,0 +1,393 @@
> +/*
> + * AMD SBI Temperature Sensor Interface (SB-TSI)
> + *
> + * Copyright 2021 Google LLC
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
> + * for more details.
> + */
> +
> +#include "qemu/osdep.h"
> +#include "hw/i2c/smbus_slave.h"
> +#include "hw/irq.h"
> +#include "migration/vmstate.h"
> +#include "qapi/error.h"
> +#include "qapi/visitor.h"
> +#include "qemu/log.h"
> +#include "qemu/module.h"
> +#include "trace.h"
> +
> +#define TYPE_SBTSI "sbtsi"

If you add include/hw/sensor/sbtsi.h, please define the type there, ...

> +/*
> + * SB-TSI registers only support SMBus byte data access. "_INT" registers are
> + * the integer part of a temperature value or limit, and "_DEC" registers are
> + * corresponding decimal parts.
> + */
> +#define SBTSI_REG_TEMP_INT      0x01 /* RO */
> +#define SBTSI_REG_STATUS        0x02 /* RO */
> +#define SBTSI_REG_CONFIG        0x03 /* RO */
> +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */
> +#define SBTSI_REG_TEMP_LOW_INT  0x08 /* RW */
> +#define SBTSI_REG_CONFIG_WR     0x09 /* RW */
> +#define SBTSI_REG_TEMP_DEC      0x10 /* RO */
> +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */
> +#define SBTSI_REG_TEMP_LOW_DEC  0x14 /* RW */
> +#define SBTSI_REG_ALERT_CONFIG  0xBF /* RW */
> +#define SBTSI_REG_MAN           0xFE /* RO */
> +#define SBTSI_REG_REV           0xFF /* RO */
> +
> +#define SBTSI_STATUS_HIGH_ALERT BIT(4)
> +#define SBTSI_STATUS_LOW_ALERT  BIT(3)
> +#define SBTSI_CONFIG_ALERT_MASK BIT(7)
> +#define SBTSI_ALARM_EN          BIT(0)

beside these definitions can be share with qtests.

> +/* The temperature we stored are in units of 0.125 degrees. */
> +#define SBTSI_TEMP_UNIT_IN_MILLIDEGREE 125
> +
> +/*
> + * The integer part and decimal of the temperature both 8 bits.
> + * Only the top 3 bits of the decimal parts are used.
> + * So the max temperature is (2^8-1) + (2^3-1)/8 = 255.875 degrees.
> + */
> +#define SBTSI_TEMP_MAX 255875

Nitpicking, use _IN_MILLIDEGREE suffix?

> +static void sbtsi_init(Object *obj)
> +{
> +    SBTSIState *s = SBTSI(obj);
> +
> +    /* Current temperature in millidegrees. */
> +    object_property_add(obj, "temperature", "uint32",

Can we explicit as "temperature_uC"?

> +                        sbtsi_get_temperature, sbtsi_set_temperature,
> +                        NULL, NULL);
> +    qdev_init_gpio_out_named(DEVICE(obj), &s->alarm, SBTSI_ALARM_L, 0);
> +}
> +
> +static void sbtsi_class_init(ObjectClass *klass, void *data)
> +{
> +    ResettableClass *rc = RESETTABLE_CLASS(klass);
> +    DeviceClass *dc = DEVICE_CLASS(klass);
> +    SMBusDeviceClass *k = SMBUS_DEVICE_CLASS(klass);
> +
> +    dc->desc = "SB-TSI Temperature Sensor";
> +    dc->vmsd = &vmstate_sbtsi;
> +    k->write_data = sbtsi_write_data;
> +    k->receive_byte = sbtsi_read_byte;
> +    rc->phases.enter = sbtsi_enter_reset;
> +    rc->phases.hold = sbtsi_hold_reset;

If my previous patch [*] were in, I'd have asked for:

       set_bit(DEVICE_CATEGORY_SENSOR, dc->categories);

But since it isn't, I'll keep an eye on which goes in first.

[*] https://www.mail-archive.com/[e-mail]/msg847088.html

> diff --git a/tests/qtest/tmp_sbtsi-test.c b/tests/qtest/tmp_sbtsi-test.c
> new file mode 100644
> index 0000000000..7f5fafacc7
> --- /dev/null
> +++ b/tests/qtest/tmp_sbtsi-test.c
> @@ -0,0 +1,180 @@
> +/*
> + * QTests for the SBTSI temperature sensor
> + *
> + * Copyright 2020 Google LLC
> + *
> + * This program is free software; you can redistribute it and/or modify it
> + * under the terms of the GNU General Public License as published by the
> + * Free Software Foundation; either version 2 of the License, or
> + * (at your option) any later version.
> + *
> + * This program is distributed in the hope that it will be useful, but WITHOUT
> + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
> + * for more details.
> + */
> +
> +#include "qemu/osdep.h"
> +
> +#include "libqtest-single.h"
> +#include "libqos/qgraph.h"
> +#include "libqos/i2c.h"
> +#include "qapi/qmp/qdict.h"
> +#include "qemu/bitops.h"
> +
> +#define TEST_ID   "sbtsi-test"
> +#define TEST_ADDR (0x4c)
> +
> +/*
> + * SB-TSI registers only support SMBus byte data access. "_INT" registers are
> + * the integer part of a temperature value or limit, and "_DEC" registers are
> + * corresponding decimal parts.
> + */
> +#define REG_TEMP_INT      0x01 /* RO */
> +#define REG_STATUS        0x02 /* RO */
> +#define REG_CONFIG        0x03 /* RO */
> +#define REG_TEMP_HIGH_INT 0x07 /* RW */
> +#define REG_TEMP_LOW_INT  0x08 /* RW */
> +#define REG_CONFIG_WR     0x09 /* RW */
> +#define REG_TEMP_DEC      0x10 /* RO */
> +#define REG_TEMP_HIGH_DEC 0x13 /* RW */
> +#define REG_TEMP_LOW_DEC  0x14 /* RW */
> +#define REG_ALERT_CONFIG  0xBF /* RW */
> +
> +#define STATUS_HIGH_ALERT BIT(4)
> +#define STATUS_LOW_ALERT  BIT(3)
> +#define CONFIG_ALERT_MASK BIT(7)
> +#define ALARM_EN          BIT(0)

This is the part that could be shared in "include/hw/sensor/sbtsi.h".

> +/* The temperature stored are in units of 0.125 degrees. */
> +#define TEMP_UNIT_IN_MILLIDEGREE 125
> +#define LIMIT_LOW (10500)
> +#define LIMIT_HIGH (55125)

Nitpicking again, _IN_MILLIDEGREE suffix for coherency?

> +static uint32_t qmp_sbtsi_get_temperature(const char *id)
> +{
> +    QDict *response;
> +    int ret;
> +
> +    response = qmp("{ 'execute': 'qom-get', 'arguments': { 'path': %s, "
> +                   "'property': 'temperature' } }", id);

If renamed earlier, here 'temperature_uC'.

> +    g_assert(qdict_haskey(response, "return"));
> +    ret = (uint32_t)qdict_get_int(response, "return");
> +    qobject_unref(response);
> +    return ret;
> +}
> +
> +static void qmp_sbtsi_set_temperature(const char *id, uint32_t value)
> +{
> +    QDict *response;
> +
> +    response = qmp("{ 'execute': 'qom-set', 'arguments': { 'path': %s, "
> +                   "'property': 'temperature', 'value': %d } }", id, value);
> +    g_assert(qdict_haskey(response, "return"));
> +    qobject_unref(response);
> +}

Thanks,

Phil.

Patrick Leis Jan. 10, 2022, 5:14 p.m. UTC | #3

On Mon, Jan 10, 2022 at 1:35 AM Philippe Mathieu-Daudé <[e-mail]>
wrote:

> Hi Patrick,
>
> On 1/8/22 04:04, Patrick Venture wrote:
> > From: Hao Wu <[e-mail]>
> >
> > SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
> > interface that reports AMD SoC's Ttcl (normalized temperature),
> > and resembles a typical 8-pin remote temperature sensor's I2C interface
> > to BMC.
> >
> > This patch implements a basic AMD SB-TSI sensor that is
> > compatible with the open-source data sheet from AMD and Linux
> > kernel driver.
> >
> > Reference:
> > Linux kernel driver:
> > https://lkml.org/lkml/2020/12/11/968
> > Register Map:
> > https://developer.amd.com/wp-content/resources/56255_3_03.PDF
> > (Chapter 6)
> >
> > Signed-off-by: Hao Wu <[e-mail]>
> > Reviewed-by: Doug Evans <[e-mail]>
> > ---
> >  hw/sensor/Kconfig            |   4 +
> >  hw/sensor/meson.build        |   1 +
> >  hw/sensor/tmp_sbtsi.c        | 393 +++++++++++++++++++++++++++++++++++
> >  hw/sensor/trace-events       |   5 +
> >  hw/sensor/trace.h            |   1 +
> >  meson.build                  |   1 +
>
> >  tests/qtest/meson.build      |   1 +
> >  tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++
>
> Up to Thomas for qtest, but I'd rather split in 2 patches since
> different set of maintainers / reviewers.
>
> > +++ b/hw/sensor/tmp_sbtsi.c
> > @@ -0,0 +1,393 @@
> > +/*
> > + * AMD SBI Temperature Sensor Interface (SB-TSI)
> > + *
> > + * Copyright 2021 Google LLC
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> it
> > + * under the terms of the GNU General Public License as published by the
> > + * Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + *
> > + * This program is distributed in the hope that it will be useful, but
> WITHOUT
> > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
> > + * for more details.
> > + */
> > +
> > +#include "qemu/osdep.h"
> > +#include "hw/i2c/smbus_slave.h"
> > +#include "hw/irq.h"
> > +#include "migration/vmstate.h"
> > +#include "qapi/error.h"
> > +#include "qapi/visitor.h"
> > +#include "qemu/log.h"
> > +#include "qemu/module.h"
> > +#include "trace.h"
> > +
> > +#define TYPE_SBTSI "sbtsi"
>
> If you add include/hw/sensor/sbtsi.h, please define the type there, ...
>
> > +/*
> > + * SB-TSI registers only support SMBus byte data access. "_INT"
> registers are
> > + * the integer part of a temperature value or limit, and "_DEC"
> registers are
> > + * corresponding decimal parts.
> > + */
> > +#define SBTSI_REG_TEMP_INT      0x01 /* RO */
> > +#define SBTSI_REG_STATUS        0x02 /* RO */
> > +#define SBTSI_REG_CONFIG        0x03 /* RO */
> > +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */
> > +#define SBTSI_REG_TEMP_LOW_INT  0x08 /* RW */
> > +#define SBTSI_REG_CONFIG_WR     0x09 /* RW */
> > +#define SBTSI_REG_TEMP_DEC      0x10 /* RO */
> > +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */
> > +#define SBTSI_REG_TEMP_LOW_DEC  0x14 /* RW */
> > +#define SBTSI_REG_ALERT_CONFIG  0xBF /* RW */
> > +#define SBTSI_REG_MAN           0xFE /* RO */
> > +#define SBTSI_REG_REV           0xFF /* RO */
> > +
> > +#define SBTSI_STATUS_HIGH_ALERT BIT(4)
> > +#define SBTSI_STATUS_LOW_ALERT  BIT(3)
> > +#define SBTSI_CONFIG_ALERT_MASK BIT(7)
> > +#define SBTSI_ALARM_EN          BIT(0)
>
> beside these definitions can be share with qtests.
>
> > +/* The temperature we stored are in units of 0.125 degrees. */
> > +#define SBTSI_TEMP_UNIT_IN_MILLIDEGREE 125
> > +
> > +/*
> > + * The integer part and decimal of the temperature both 8 bits.
> > + * Only the top 3 bits of the decimal parts are used.
> > + * So the max temperature is (2^8-1) + (2^3-1)/8 = 255.875 degrees.
> > + */
> > +#define SBTSI_TEMP_MAX 255875
>
> Nitpicking, use _IN_MILLIDEGREE suffix?
>

I haven't seen this suffix before, is this a style you'd like to start
seeing?


>
> > +static void sbtsi_init(Object *obj)
> > +{
> > +    SBTSIState *s = SBTSI(obj);
> > +
> > +    /* Current temperature in millidegrees. */
> > +    object_property_add(obj, "temperature", "uint32",
>
> Can we explicit as "temperature_uC"?
>

We can, but that's non-standard.  As I recall most temperature sensors in
hw/sensors are in millidegrees, but none have unit suffixes.


>
> > +                        sbtsi_get_temperature, sbtsi_set_temperature,
> > +                        NULL, NULL);
> > +    qdev_init_gpio_out_named(DEVICE(obj), &s->alarm, SBTSI_ALARM_L, 0);
> > +}
> > +
> > +static void sbtsi_class_init(ObjectClass *klass, void *data)
> > +{
> > +    ResettableClass *rc = RESETTABLE_CLASS(klass);
> > +    DeviceClass *dc = DEVICE_CLASS(klass);
> > +    SMBusDeviceClass *k = SMBUS_DEVICE_CLASS(klass);
> > +
> > +    dc->desc = "SB-TSI Temperature Sensor";
> > +    dc->vmsd = &vmstate_sbtsi;
> > +    k->write_data = sbtsi_write_data;
> > +    k->receive_byte = sbtsi_read_byte;
> > +    rc->phases.enter = sbtsi_enter_reset;
> > +    rc->phases.hold = sbtsi_hold_reset;
>
> If my previous patch [*] were in, I'd have asked for:
>
>        set_bit(DEVICE_CATEGORY_SENSOR, dc->categories);
>
> But since it isn't, I'll keep an eye on which goes in first.
>
> [*] https://www.mail-archive.com/[e-mail]/msg847088.html
>
> > diff --git a/tests/qtest/tmp_sbtsi-test.c b/tests/qtest/tmp_sbtsi-test.c
> > new file mode 100644
> > index 0000000000..7f5fafacc7
> > --- /dev/null
> > +++ b/tests/qtest/tmp_sbtsi-test.c
> > @@ -0,0 +1,180 @@
> > +/*
> > + * QTests for the SBTSI temperature sensor
> > + *
> > + * Copyright 2020 Google LLC
> > + *
> > + * This program is free software; you can redistribute it and/or modify
> it
> > + * under the terms of the GNU General Public License as published by the
> > + * Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + *
> > + * This program is distributed in the hope that it will be useful, but
> WITHOUT
> > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
> > + * for more details.
> > + */
> > +
> > +#include "qemu/osdep.h"
> > +
> > +#include "libqtest-single.h"
> > +#include "libqos/qgraph.h"
> > +#include "libqos/i2c.h"
> > +#include "qapi/qmp/qdict.h"
> > +#include "qemu/bitops.h"
> > +
> > +#define TEST_ID   "sbtsi-test"
> > +#define TEST_ADDR (0x4c)
> > +
> > +/*
> > + * SB-TSI registers only support SMBus byte data access. "_INT"
> registers are
> > + * the integer part of a temperature value or limit, and "_DEC"
> registers are
> > + * corresponding decimal parts.
> > + */
> > +#define REG_TEMP_INT      0x01 /* RO */
> > +#define REG_STATUS        0x02 /* RO */
> > +#define REG_CONFIG        0x03 /* RO */
> > +#define REG_TEMP_HIGH_INT 0x07 /* RW */
> > +#define REG_TEMP_LOW_INT  0x08 /* RW */
> > +#define REG_CONFIG_WR     0x09 /* RW */
> > +#define REG_TEMP_DEC      0x10 /* RO */
> > +#define REG_TEMP_HIGH_DEC 0x13 /* RW */
> > +#define REG_TEMP_LOW_DEC  0x14 /* RW */
> > +#define REG_ALERT_CONFIG  0xBF /* RW */
> > +
> > +#define STATUS_HIGH_ALERT BIT(4)
> > +#define STATUS_LOW_ALERT  BIT(3)
> > +#define CONFIG_ALERT_MASK BIT(7)
> > +#define ALARM_EN          BIT(0)
>
> This is the part that could be shared in "include/hw/sensor/sbtsi.h".
>

Ack.


>
> > +/* The temperature stored are in units of 0.125 degrees. */
> > +#define TEMP_UNIT_IN_MILLIDEGREE 125
> > +#define LIMIT_LOW (10500)
> > +#define LIMIT_HIGH (55125)
>
> Nitpicking again, _IN_MILLIDEGREE suffix for coherency?
>
> > +static uint32_t qmp_sbtsi_get_temperature(const char *id)
> > +{
> > +    QDict *response;
> > +    int ret;
> > +
> > +    response = qmp("{ 'execute': 'qom-get', 'arguments': { 'path': %s, "
> > +                   "'property': 'temperature' } }", id);
>
> If renamed earlier, here 'temperature_uC'.
>
> > +    g_assert(qdict_haskey(response, "return"));
> > +    ret = (uint32_t)qdict_get_int(response, "return");
> > +    qobject_unref(response);
> > +    return ret;
> > +}
> > +
> > +static void qmp_sbtsi_set_temperature(const char *id, uint32_t value)
> > +{
> > +    QDict *response;
> > +
> > +    response = qmp("{ 'execute': 'qom-set', 'arguments': { 'path': %s, "
> > +                   "'property': 'temperature', 'value': %d } }", id,
> value);
> > +    g_assert(qdict_haskey(response, "return"));
> > +    qobject_unref(response);
> > +}
>
> Thanks,
>
> Phil.
>

v2 will come with the header split.  I can split the qtests into a separate
patch.  Was your point because the patches are applied to different staging
trees?  Because I would think it ideal to have the qtests and the
corresponding code applied together so that it's easy to know it's
working.  If this isn't standard, I can definitely split them.

Patrick

Philippe Mathieu-Daudé Jan. 10, 2022, 7:30 p.m. UTC | #4

On 1/10/22 18:14, Patrick Venture wrote:
> On Mon, Jan 10, 2022 at 1:35 AM Philippe Mathieu-Daudé <[e-mail]
> <mailto:[e-mail]>> wrote:
> 
>     Hi Patrick,
> 
>     On 1/8/22 04:04, Patrick Venture wrote:
>     > From: Hao Wu <[e-mail] <mailto:[e-mail]>>
>     >
>     > SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
>     > interface that reports AMD SoC's Ttcl (normalized temperature),
>     > and resembles a typical 8-pin remote temperature sensor's I2C
>     interface
>     > to BMC.
>     >
>     > This patch implements a basic AMD SB-TSI sensor that is
>     > compatible with the open-source data sheet from AMD and Linux
>     > kernel driver.
>     >
>     > Reference:
>     > Linux kernel driver:
>     > https://lkml.org/lkml/2020/12/11/968
>     <https://lkml.org/lkml/2020/12/11/968>
>     > Register Map:
>     > https://developer.amd.com/wp-content/resources/56255_3_03.PDF
>     <https://developer.amd.com/wp-content/resources/56255_3_03.PDF>
>     > (Chapter 6)
>     >
>     > Signed-off-by: Hao Wu <[e-mail]
>     <mailto:[e-mail]>>
>     > Reviewed-by: Doug Evans <[e-mail] <mailto:[e-mail]>>
>     > ---
>     >  hw/sensor/Kconfig            |   4 +
>     >  hw/sensor/meson.build        |   1 +
>     >  hw/sensor/tmp_sbtsi.c        | 393
>     +++++++++++++++++++++++++++++++++++
>     >  hw/sensor/trace-events       |   5 +
>     >  hw/sensor/trace.h            |   1 +
>     >  meson.build                  |   1 +
> 
>     >  tests/qtest/meson.build      |   1 +
>     >  tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++
> 
>     Up to Thomas for qtest, but I'd rather split in 2 patches since
>     different set of maintainers / reviewers.
> 
>     > +++ b/hw/sensor/tmp_sbtsi.c
>     > @@ -0,0 +1,393 @@
>     > +/*
>     > + * AMD SBI Temperature Sensor Interface (SB-TSI)
>     > + *
>     > + * Copyright 2021 Google LLC
>     > + *
>     > + * This program is free software; you can redistribute it and/or
>     modify it
>     > + * under the terms of the GNU General Public License as published
>     by the
>     > + * Free Software Foundation; either version 2 of the License, or
>     > + * (at your option) any later version.
>     > + *
>     > + * This program is distributed in the hope that it will be
>     useful, but WITHOUT
>     > + * ANY WARRANTY; without even the implied warranty of
>     MERCHANTABILITY or
>     > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
>     License
>     > + * for more details.
>     > + */
>     > +
>     > +#include "qemu/osdep.h"
>     > +#include "hw/i2c/smbus_slave.h"
>     > +#include "hw/irq.h"
>     > +#include "migration/vmstate.h"
>     > +#include "qapi/error.h"
>     > +#include "qapi/visitor.h"
>     > +#include "qemu/log.h"
>     > +#include "qemu/module.h"
>     > +#include "trace.h"
>     > +
>     > +#define TYPE_SBTSI "sbtsi"
> 
>     If you add include/hw/sensor/sbtsi.h, please define the type there, ...
> 
>     > +/*
>     > + * SB-TSI registers only support SMBus byte data access. "_INT"
>     registers are
>     > + * the integer part of a temperature value or limit, and "_DEC"
>     registers are
>     > + * corresponding decimal parts.
>     > + */
>     > +#define SBTSI_REG_TEMP_INT      0x01 /* RO */
>     > +#define SBTSI_REG_STATUS        0x02 /* RO */
>     > +#define SBTSI_REG_CONFIG        0x03 /* RO */
>     > +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */
>     > +#define SBTSI_REG_TEMP_LOW_INT  0x08 /* RW */
>     > +#define SBTSI_REG_CONFIG_WR     0x09 /* RW */
>     > +#define SBTSI_REG_TEMP_DEC      0x10 /* RO */
>     > +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */
>     > +#define SBTSI_REG_TEMP_LOW_DEC  0x14 /* RW */
>     > +#define SBTSI_REG_ALERT_CONFIG  0xBF /* RW */
>     > +#define SBTSI_REG_MAN           0xFE /* RO */
>     > +#define SBTSI_REG_REV           0xFF /* RO */
>     > +
>     > +#define SBTSI_STATUS_HIGH_ALERT BIT(4)
>     > +#define SBTSI_STATUS_LOW_ALERT  BIT(3)
>     > +#define SBTSI_CONFIG_ALERT_MASK BIT(7)
>     > +#define SBTSI_ALARM_EN          BIT(0)
> 
>     beside these definitions can be share with qtests.
> 
>     > +/* The temperature we stored are in units of 0.125 degrees. */
>     > +#define SBTSI_TEMP_UNIT_IN_MILLIDEGREE 125
>     > +
>     > +/*
>     > + * The integer part and decimal of the temperature both 8 bits.
>     > + * Only the top 3 bits of the decimal parts are used.
>     > + * So the max temperature is (2^8-1) + (2^3-1)/8 = 255.875 degrees.
>     > + */
>     > +#define SBTSI_TEMP_MAX 255875
> 
>     Nitpicking, use _IN_MILLIDEGREE suffix?
> 
> 
> I haven't seen this suffix before, is this a style you'd like to start
> seeing?

Well you used it few lines earlier, in the previous definition:
SBTSI_TEMP_UNIT_IN_MILLIDEGREE :)

>     > +static void sbtsi_init(Object *obj)
>     > +{
>     > +    SBTSIState *s = SBTSI(obj);
>     > +
>     > +    /* Current temperature in millidegrees. */
>     > +    object_property_add(obj, "temperature", "uint32",
> 
>     Can we explicit as "temperature_uC"?
> 
> 
> We can, but that's non-standard.  As I recall most temperature sensors
> in hw/sensors are in millidegrees, but none have unit suffixes.

I tend to agree, but this is not obvious to everybody.

I once started sanitizing / enforcing this but never got there:
https://www.mail-archive.com/[e-mail]/msg65192.html

So I don't mind for your patch, if I keep looking at temp sensors
I'll clean up on top later.

>     > +                        sbtsi_get_temperature, sbtsi_set_temperature,
>     > +                        NULL, NULL);
>     > +    qdev_init_gpio_out_named(DEVICE(obj), &s->alarm,
>     SBTSI_ALARM_L, 0);
>     > +}
>     > +
>     > +static void sbtsi_class_init(ObjectClass *klass, void *data)
>     > +{
>     > +    ResettableClass *rc = RESETTABLE_CLASS(klass);
>     > +    DeviceClass *dc = DEVICE_CLASS(klass);
>     > +    SMBusDeviceClass *k = SMBUS_DEVICE_CLASS(klass);
>     > +
>     > +    dc->desc = "SB-TSI Temperature Sensor";
>     > +    dc->vmsd = &vmstate_sbtsi;
>     > +    k->write_data = sbtsi_write_data;
>     > +    k->receive_byte = sbtsi_read_byte;
>     > +    rc->phases.enter = sbtsi_enter_reset;
>     > +    rc->phases.hold = sbtsi_hold_reset;
> 
>     If my previous patch [*] were in, I'd have asked for:
> 
>            set_bit(DEVICE_CATEGORY_SENSOR, dc->categories);
> 
>     But since it isn't, I'll keep an eye on which goes in first.
> 
>     [*]
>     https://www.mail-archive.com/[e-mail]/msg847088.html
>     <https://www.mail-archive.com/[e-mail]/msg847088.html>
> 
>     > diff --git a/tests/qtest/tmp_sbtsi-test.c
>     b/tests/qtest/tmp_sbtsi-test.c
>     > new file mode 100644
>     > index 0000000000..7f5fafacc7
>     > --- /dev/null
>     > +++ b/tests/qtest/tmp_sbtsi-test.c
>     > @@ -0,0 +1,180 @@
>     > +/*
>     > + * QTests for the SBTSI temperature sensor
>     > + *
>     > + * Copyright 2020 Google LLC
>     > + *
>     > + * This program is free software; you can redistribute it and/or
>     modify it
>     > + * under the terms of the GNU General Public License as published
>     by the
>     > + * Free Software Foundation; either version 2 of the License, or
>     > + * (at your option) any later version.
>     > + *
>     > + * This program is distributed in the hope that it will be
>     useful, but WITHOUT
>     > + * ANY WARRANTY; without even the implied warranty of
>     MERCHANTABILITY or
>     > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
>     License
>     > + * for more details.
>     > + */
>     > +
>     > +#include "qemu/osdep.h"
>     > +
>     > +#include "libqtest-single.h"
>     > +#include "libqos/qgraph.h"
>     > +#include "libqos/i2c.h"
>     > +#include "qapi/qmp/qdict.h"
>     > +#include "qemu/bitops.h"
>     > +
>     > +#define TEST_ID   "sbtsi-test"
>     > +#define TEST_ADDR (0x4c)
>     > +
>     > +/*
>     > + * SB-TSI registers only support SMBus byte data access. "_INT"
>     registers are
>     > + * the integer part of a temperature value or limit, and "_DEC"
>     registers are
>     > + * corresponding decimal parts.
>     > + */
>     > +#define REG_TEMP_INT      0x01 /* RO */
>     > +#define REG_STATUS        0x02 /* RO */
>     > +#define REG_CONFIG        0x03 /* RO */
>     > +#define REG_TEMP_HIGH_INT 0x07 /* RW */
>     > +#define REG_TEMP_LOW_INT  0x08 /* RW */
>     > +#define REG_CONFIG_WR     0x09 /* RW */
>     > +#define REG_TEMP_DEC      0x10 /* RO */
>     > +#define REG_TEMP_HIGH_DEC 0x13 /* RW */
>     > +#define REG_TEMP_LOW_DEC  0x14 /* RW */
>     > +#define REG_ALERT_CONFIG  0xBF /* RW */
>     > +
>     > +#define STATUS_HIGH_ALERT BIT(4)
>     > +#define STATUS_LOW_ALERT  BIT(3)
>     > +#define CONFIG_ALERT_MASK BIT(7)
>     > +#define ALARM_EN          BIT(0)
> 
>     This is the part that could be shared in "include/hw/sensor/sbtsi.h".
> 
> 
> Ack.
>  
> 
> 
>     > +/* The temperature stored are in units of 0.125 degrees. */
>     > +#define TEMP_UNIT_IN_MILLIDEGREE 125
>     > +#define LIMIT_LOW (10500)
>     > +#define LIMIT_HIGH (55125)
> 
>     Nitpicking again, _IN_MILLIDEGREE suffix for coherency?
> 
>     > +static uint32_t qmp_sbtsi_get_temperature(const char *id)
>     > +{
>     > +    QDict *response;
>     > +    int ret;
>     > +
>     > +    response = qmp("{ 'execute': 'qom-get', 'arguments': {
>     'path': %s, "
>     > +                   "'property': 'temperature' } }", id);
> 
>     If renamed earlier, here 'temperature_uC'.
> 
>     > +    g_assert(qdict_haskey(response, "return"));
>     > +    ret = (uint32_t)qdict_get_int(response, "return");
>     > +    qobject_unref(response);
>     > +    return ret;
>     > +}
>     > +
>     > +static void qmp_sbtsi_set_temperature(const char *id, uint32_t value)
>     > +{
>     > +    QDict *response;
>     > +
>     > +    response = qmp("{ 'execute': 'qom-set', 'arguments': {
>     'path': %s, "
>     > +                   "'property': 'temperature', 'value': %d } }",
>     id, value);
>     > +    g_assert(qdict_haskey(response, "return"));
>     > +    qobject_unref(response);
>     > +}
> 
>     Thanks,
> 
>     Phil.
> 
> 
> v2 will come with the header split.  I can split the qtests into a
> separate patch.  Was your point because the patches are applied to
> different staging trees?  Because I would think it ideal to have the
> qtests and the corresponding code applied together so that it's easy to
> know it's working.  If this isn't standard, I can definitely split them.

If split, both patches certainly should be queued consecutively via the
same tree. I asked the split because I'm OK to give a R-b tag for the
hw/ part, but am not sure about the tests/ part. Possibly others would
be OK to review the qtest but would be unsure about the hw/ part.

Patrick Leis Jan. 10, 2022, 7:41 p.m. UTC | #5

On Mon, Jan 10, 2022 at 11:30 AM Philippe Mathieu-Daudé <[e-mail]>
wrote:

> On 1/10/22 18:14, Patrick Venture wrote:
> > On Mon, Jan 10, 2022 at 1:35 AM Philippe Mathieu-Daudé <[e-mail]
> > <mailto:[e-mail]>> wrote:
> >
> >     Hi Patrick,
> >
> >     On 1/8/22 04:04, Patrick Venture wrote:
> >     > From: Hao Wu <[e-mail] <mailto:[e-mail]>>
> >     >
> >     > SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
> >     > interface that reports AMD SoC's Ttcl (normalized temperature),
> >     > and resembles a typical 8-pin remote temperature sensor's I2C
> >     interface
> >     > to BMC.
> >     >
> >     > This patch implements a basic AMD SB-TSI sensor that is
> >     > compatible with the open-source data sheet from AMD and Linux
> >     > kernel driver.
> >     >
> >     > Reference:
> >     > Linux kernel driver:
> >     > https://lkml.org/lkml/2020/12/11/968
> >     <https://lkml.org/lkml/2020/12/11/968>
> >     > Register Map:
> >     > https://developer.amd.com/wp-content/resources/56255_3_03.PDF
> >     <https://developer.amd.com/wp-content/resources/56255_3_03.PDF>
> >     > (Chapter 6)
> >     >
> >     > Signed-off-by: Hao Wu <[e-mail]
> >     <mailto:[e-mail]>>
> >     > Reviewed-by: Doug Evans <[e-mail] <mailto:[e-mail]>>
> >     > ---
> >     >  hw/sensor/Kconfig            |   4 +
> >     >  hw/sensor/meson.build        |   1 +
> >     >  hw/sensor/tmp_sbtsi.c        | 393
> >     +++++++++++++++++++++++++++++++++++
> >     >  hw/sensor/trace-events       |   5 +
> >     >  hw/sensor/trace.h            |   1 +
> >     >  meson.build                  |   1 +
> >
> >     >  tests/qtest/meson.build      |   1 +
> >     >  tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++
> >
> >     Up to Thomas for qtest, but I'd rather split in 2 patches since
> >     different set of maintainers / reviewers.
> >
> >     > +++ b/hw/sensor/tmp_sbtsi.c
> >     > @@ -0,0 +1,393 @@
> >     > +/*
> >     > + * AMD SBI Temperature Sensor Interface (SB-TSI)
> >     > + *
> >     > + * Copyright 2021 Google LLC
> >     > + *
> >     > + * This program is free software; you can redistribute it and/or
> >     modify it
> >     > + * under the terms of the GNU General Public License as published
> >     by the
> >     > + * Free Software Foundation; either version 2 of the License, or
> >     > + * (at your option) any later version.
> >     > + *
> >     > + * This program is distributed in the hope that it will be
> >     useful, but WITHOUT
> >     > + * ANY WARRANTY; without even the implied warranty of
> >     MERCHANTABILITY or
> >     > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
> >     License
> >     > + * for more details.
> >     > + */
> >     > +
> >     > +#include "qemu/osdep.h"
> >     > +#include "hw/i2c/smbus_slave.h"
> >     > +#include "hw/irq.h"
> >     > +#include "migration/vmstate.h"
> >     > +#include "qapi/error.h"
> >     > +#include "qapi/visitor.h"
> >     > +#include "qemu/log.h"
> >     > +#include "qemu/module.h"
> >     > +#include "trace.h"
> >     > +
> >     > +#define TYPE_SBTSI "sbtsi"
> >
> >     If you add include/hw/sensor/sbtsi.h, please define the type there,
> ...
> >
> >     > +/*
> >     > + * SB-TSI registers only support SMBus byte data access. "_INT"
> >     registers are
> >     > + * the integer part of a temperature value or limit, and "_DEC"
> >     registers are
> >     > + * corresponding decimal parts.
> >     > + */
> >     > +#define SBTSI_REG_TEMP_INT      0x01 /* RO */
> >     > +#define SBTSI_REG_STATUS        0x02 /* RO */
> >     > +#define SBTSI_REG_CONFIG        0x03 /* RO */
> >     > +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */
> >     > +#define SBTSI_REG_TEMP_LOW_INT  0x08 /* RW */
> >     > +#define SBTSI_REG_CONFIG_WR     0x09 /* RW */
> >     > +#define SBTSI_REG_TEMP_DEC      0x10 /* RO */
> >     > +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */
> >     > +#define SBTSI_REG_TEMP_LOW_DEC  0x14 /* RW */
> >     > +#define SBTSI_REG_ALERT_CONFIG  0xBF /* RW */
> >     > +#define SBTSI_REG_MAN           0xFE /* RO */
> >     > +#define SBTSI_REG_REV           0xFF /* RO */
> >     > +
> >     > +#define SBTSI_STATUS_HIGH_ALERT BIT(4)
> >     > +#define SBTSI_STATUS_LOW_ALERT  BIT(3)
> >     > +#define SBTSI_CONFIG_ALERT_MASK BIT(7)
> >     > +#define SBTSI_ALARM_EN          BIT(0)
> >
> >     beside these definitions can be share with qtests.
> >
> >     > +/* The temperature we stored are in units of 0.125 degrees. */
> >     > +#define SBTSI_TEMP_UNIT_IN_MILLIDEGREE 125
> >     > +
> >     > +/*
> >     > + * The integer part and decimal of the temperature both 8 bits.
> >     > + * Only the top 3 bits of the decimal parts are used.
> >     > + * So the max temperature is (2^8-1) + (2^3-1)/8 = 255.875
> degrees.
> >     > + */
> >     > +#define SBTSI_TEMP_MAX 255875
> >
> >     Nitpicking, use _IN_MILLIDEGREE suffix?
> >
> >
> > I haven't seen this suffix before, is this a style you'd like to start
> > seeing?
>
> Well you used it few lines earlier, in the previous definition:
> SBTSI_TEMP_UNIT_IN_MILLIDEGREE :)
>

Ha, thanks! :) I didn't notice Hao had done that. I'll make it consistent.

>
> >     > +static void sbtsi_init(Object *obj)
> >     > +{
> >     > +    SBTSIState *s = SBTSI(obj);
> >     > +
> >     > +    /* Current temperature in millidegrees. */
> >     > +    object_property_add(obj, "temperature", "uint32",
> >
> >     Can we explicit as "temperature_uC"?
> >
> >
> > We can, but that's non-standard.  As I recall most temperature sensors
> > in hw/sensors are in millidegrees, but none have unit suffixes.
>
> I tend to agree, but this is not obvious to everybody.
>
> I once started sanitizing / enforcing this but never got there:
> https://www.mail-archive.com/[e-mail]/msg65192.html
>
> So I don't mind for your patch, if I keep looking at temp sensors
> I'll clean up on top later.
>

Thanks, it seems like the type of change that was best as sweeping vs a
one-off.


>
> >     > +                        sbtsi_get_temperature,
> sbtsi_set_temperature,
> >     > +                        NULL, NULL);
> >     > +    qdev_init_gpio_out_named(DEVICE(obj), &s->alarm,
> >     SBTSI_ALARM_L, 0);
> >     > +}
> >     > +
> >     > +static void sbtsi_class_init(ObjectClass *klass, void *data)
> >     > +{
> >     > +    ResettableClass *rc = RESETTABLE_CLASS(klass);
> >     > +    DeviceClass *dc = DEVICE_CLASS(klass);
> >     > +    SMBusDeviceClass *k = SMBUS_DEVICE_CLASS(klass);
> >     > +
> >     > +    dc->desc = "SB-TSI Temperature Sensor";
> >     > +    dc->vmsd = &vmstate_sbtsi;
> >     > +    k->write_data = sbtsi_write_data;
> >     > +    k->receive_byte = sbtsi_read_byte;
> >     > +    rc->phases.enter = sbtsi_enter_reset;
> >     > +    rc->phases.hold = sbtsi_hold_reset;
> >
> >     If my previous patch [*] were in, I'd have asked for:
> >
> >            set_bit(DEVICE_CATEGORY_SENSOR, dc->categories);
> >
> >     But since it isn't, I'll keep an eye on which goes in first.
> >
> >     [*]
> >     https://www.mail-archive.com/[e-mail]/msg847088.html
> >     <https://www.mail-archive.com/[e-mail]/msg847088.html>
> >
> >     > diff --git a/tests/qtest/tmp_sbtsi-test.c
> >     b/tests/qtest/tmp_sbtsi-test.c
> >     > new file mode 100644
> >     > index 0000000000..7f5fafacc7
> >     > --- /dev/null
> >     > +++ b/tests/qtest/tmp_sbtsi-test.c
> >     > @@ -0,0 +1,180 @@
> >     > +/*
> >     > + * QTests for the SBTSI temperature sensor
> >     > + *
> >     > + * Copyright 2020 Google LLC
> >     > + *
> >     > + * This program is free software; you can redistribute it and/or
> >     modify it
> >     > + * under the terms of the GNU General Public License as published
> >     by the
> >     > + * Free Software Foundation; either version 2 of the License, or
> >     > + * (at your option) any later version.
> >     > + *
> >     > + * This program is distributed in the hope that it will be
> >     useful, but WITHOUT
> >     > + * ANY WARRANTY; without even the implied warranty of
> >     MERCHANTABILITY or
> >     > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
> >     License
> >     > + * for more details.
> >     > + */
> >     > +
> >     > +#include "qemu/osdep.h"
> >     > +
> >     > +#include "libqtest-single.h"
> >     > +#include "libqos/qgraph.h"
> >     > +#include "libqos/i2c.h"
> >     > +#include "qapi/qmp/qdict.h"
> >     > +#include "qemu/bitops.h"
> >     > +
> >     > +#define TEST_ID   "sbtsi-test"
> >     > +#define TEST_ADDR (0x4c)
> >     > +
> >     > +/*
> >     > + * SB-TSI registers only support SMBus byte data access. "_INT"
> >     registers are
> >     > + * the integer part of a temperature value or limit, and "_DEC"
> >     registers are
> >     > + * corresponding decimal parts.
> >     > + */
> >     > +#define REG_TEMP_INT      0x01 /* RO */
> >     > +#define REG_STATUS        0x02 /* RO */
> >     > +#define REG_CONFIG        0x03 /* RO */
> >     > +#define REG_TEMP_HIGH_INT 0x07 /* RW */
> >     > +#define REG_TEMP_LOW_INT  0x08 /* RW */
> >     > +#define REG_CONFIG_WR     0x09 /* RW */
> >     > +#define REG_TEMP_DEC      0x10 /* RO */
> >     > +#define REG_TEMP_HIGH_DEC 0x13 /* RW */
> >     > +#define REG_TEMP_LOW_DEC  0x14 /* RW */
> >     > +#define REG_ALERT_CONFIG  0xBF /* RW */
> >     > +
> >     > +#define STATUS_HIGH_ALERT BIT(4)
> >     > +#define STATUS_LOW_ALERT  BIT(3)
> >     > +#define CONFIG_ALERT_MASK BIT(7)
> >     > +#define ALARM_EN          BIT(0)
> >
> >     This is the part that could be shared in "include/hw/sensor/sbtsi.h".
> >
> >
> > Ack.
> >
> >
> >
> >     > +/* The temperature stored are in units of 0.125 degrees. */
> >     > +#define TEMP_UNIT_IN_MILLIDEGREE 125
> >     > +#define LIMIT_LOW (10500)
> >     > +#define LIMIT_HIGH (55125)
> >
> >     Nitpicking again, _IN_MILLIDEGREE suffix for coherency?
> >
> >     > +static uint32_t qmp_sbtsi_get_temperature(const char *id)
> >     > +{
> >     > +    QDict *response;
> >     > +    int ret;
> >     > +
> >     > +    response = qmp("{ 'execute': 'qom-get', 'arguments': {
> >     'path': %s, "
> >     > +                   "'property': 'temperature' } }", id);
> >
> >     If renamed earlier, here 'temperature_uC'.
> >
> >     > +    g_assert(qdict_haskey(response, "return"));
> >     > +    ret = (uint32_t)qdict_get_int(response, "return");
> >     > +    qobject_unref(response);
> >     > +    return ret;
> >     > +}
> >     > +
> >     > +static void qmp_sbtsi_set_temperature(const char *id, uint32_t
> value)
> >     > +{
> >     > +    QDict *response;
> >     > +
> >     > +    response = qmp("{ 'execute': 'qom-set', 'arguments': {
> >     'path': %s, "
> >     > +                   "'property': 'temperature', 'value': %d } }",
> >     id, value);
> >     > +    g_assert(qdict_haskey(response, "return"));
> >     > +    qobject_unref(response);
> >     > +}
> >
> >     Thanks,
> >
> >     Phil.
> >
> >
> > v2 will come with the header split.  I can split the qtests into a
> > separate patch.  Was your point because the patches are applied to
> > different staging trees?  Because I would think it ideal to have the
> > qtests and the corresponding code applied together so that it's easy to
> > know it's working.  If this isn't standard, I can definitely split them.
>
> If split, both patches certainly should be queued consecutively via the
> same tree. I asked the split because I'm OK to give a R-b tag for the
> hw/ part, but am not sure about the tests/ part. Possibly others would
> be OK to review the qtest but would be unsure about the hw/ part.
>

Ok, so split the patches into two commits in the same mailing thing.  That
makes sense.  I'll set that up for the v2.

Thomas Huth Jan. 13, 2022, 7:19 a.m. UTC | #6

On 10/01/2022 10.35, Philippe Mathieu-Daudé wrote:
> Hi Patrick,
> 
> On 1/8/22 04:04, Patrick Venture wrote:
>> From: Hao Wu <[e-mail]>
>>
>> SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
>> interface that reports AMD SoC's Ttcl (normalized temperature),
>> and resembles a typical 8-pin remote temperature sensor's I2C interface
>> to BMC.
>>
>> This patch implements a basic AMD SB-TSI sensor that is
>> compatible with the open-source data sheet from AMD and Linux
>> kernel driver.
>>
>> Reference:
>> Linux kernel driver:
>> https://lkml.org/lkml/2020/12/11/968
>> Register Map:
>> https://developer.amd.com/wp-content/resources/56255_3_03.PDF
>> (Chapter 6)
>>
>> Signed-off-by: Hao Wu <[e-mail]>
>> Reviewed-by: Doug Evans <[e-mail]>
>> ---
>>   hw/sensor/Kconfig            |   4 +
>>   hw/sensor/meson.build        |   1 +
>>   hw/sensor/tmp_sbtsi.c        | 393 +++++++++++++++++++++++++++++++++++
>>   hw/sensor/trace-events       |   5 +
>>   hw/sensor/trace.h            |   1 +
>>   meson.build                  |   1 +
> 
>>   tests/qtest/meson.build      |   1 +
>>   tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++
> 
> Up to Thomas for qtest, but I'd rather split in 2 patches since
> different set of maintainers / reviewers.

I don't mind too much - but anyway, I'd prefer if we could stick to "-" in 
file names here - mixing underscores and "-" in file names looks somewhat 
weird (I know, there are already some files like this, but I'd prefer if 
we'd not extend that list).

  Thomas

Corey Minyard Jan. 17, 2022, 2:05 p.m. UTC | #7

On Sun, Jan 09, 2022 at 06:17:34PM -0800, Patrick Venture wrote:
> On Fri, Jan 7, 2022 at 7:04 PM Patrick Venture <[e-mail]> wrote:
> 
> > From: Hao Wu <[e-mail]>
> >
> > SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
> > interface that reports AMD SoC's Ttcl (normalized temperature),
> > and resembles a typical 8-pin remote temperature sensor's I2C interface
> > to BMC.
> >
> > This patch implements a basic AMD SB-TSI sensor that is
> > compatible with the open-source data sheet from AMD and Linux
> > kernel driver.
> >
> > Reference:
> > Linux kernel driver:
> > https://lkml.org/lkml/2020/12/11/968
> > Register Map:
> > https://developer.amd.com/wp-content/resources/56255_3_03.PDF
> > (Chapter 6)
> >
> > Signed-off-by: Hao Wu <[e-mail]>
> > Reviewed-by: Doug Evans <[e-mail]>
> > ---
> >  hw/sensor/Kconfig            |   4 +
> >  hw/sensor/meson.build        |   1 +
> >  hw/sensor/tmp_sbtsi.c        | 393 +++++++++++++++++++++++++++++++++++
> >  hw/sensor/trace-events       |   5 +
> >  hw/sensor/trace.h            |   1 +
> >  meson.build                  |   1 +
> >  tests/qtest/meson.build      |   1 +
> >  tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++
> >  8 files changed, 586 insertions(+)
> >  create mode 100644 hw/sensor/tmp_sbtsi.c
> >  create mode 100644 hw/sensor/trace-events
> >  create mode 100644 hw/sensor/trace.h
> >  create mode 100644 tests/qtest/tmp_sbtsi-test.c
> >
> > diff --git a/hw/sensor/Kconfig b/hw/sensor/Kconfig
> > index 9c8a049b06..27f6f79c84 100644
> > --- a/hw/sensor/Kconfig
> > +++ b/hw/sensor/Kconfig
> > @@ -21,3 +21,7 @@ config ADM1272
> >  config MAX34451
> >      bool
> >      depends on I2C
> > +
> > +config AMDSBTSI
> > +    bool
> > +    depends on I2C
> > diff --git a/hw/sensor/meson.build b/hw/sensor/meson.build
> > index 059c4ca935..f7b0e645eb 100644
> > --- a/hw/sensor/meson.build
> > +++ b/hw/sensor/meson.build
> > @@ -4,3 +4,4 @@ softmmu_ss.add(when: 'CONFIG_DPS310', if_true:
> > files('dps310.c'))
> >  softmmu_ss.add(when: 'CONFIG_EMC141X', if_true: files('emc141x.c'))
> >  softmmu_ss.add(when: 'CONFIG_ADM1272', if_true: files('adm1272.c'))
> >  softmmu_ss.add(when: 'CONFIG_MAX34451', if_true: files('max34451.c'))
> > +softmmu_ss.add(when: 'CONFIG_AMDSBTSI', if_true: files('tmp_sbtsi.c'))
> > diff --git a/hw/sensor/tmp_sbtsi.c b/hw/sensor/tmp_sbtsi.c
> > new file mode 100644
> > index 0000000000..b68c7ebf61
> > --- /dev/null
> > +++ b/hw/sensor/tmp_sbtsi.c
> > @@ -0,0 +1,393 @@
> > +/*
> > + * AMD SBI Temperature Sensor Interface (SB-TSI)
> > + *
> > + * Copyright 2021 Google LLC
> > + *
> > + * This program is free software; you can redistribute it and/or modify it
> > + * under the terms of the GNU General Public License as published by the
> > + * Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + *
> > + * This program is distributed in the hope that it will be useful, but
> > WITHOUT
> > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
> > + * for more details.
> > + */
> > +
> > +#include "qemu/osdep.h"
> > +#include "hw/i2c/smbus_slave.h"
> > +#include "hw/irq.h"
> > +#include "migration/vmstate.h"
> > +#include "qapi/error.h"
> > +#include "qapi/visitor.h"
> > +#include "qemu/log.h"
> > +#include "qemu/module.h"
> > +#include "trace.h"
> > +
> > +#define TYPE_SBTSI "sbtsi"
> > +#define SBTSI(obj) OBJECT_CHECK(SBTSIState, (obj), TYPE_SBTSI)
> > +
> > +/**
> > + * SBTSIState:
> > + * temperatures are in units of 0.125 degrees
> > + * @temperature: Temperature
> > + * @limit_low: Lowest temperature
> > + * @limit_high: Highest temperature
> > + * @status: The status register
> > + * @config: The config register
> > + * @alert_config: The config for alarm_l output.
> > + * @addr: The address to read/write for the next cmd.
> > + * @alarm: The alarm_l output pin (GPIO)
> > + */
> > +typedef struct SBTSIState {
> > +    SMBusDevice parent;
> > +
> > +    uint32_t temperature;
> > +    uint32_t limit_low;
> > +    uint32_t limit_high;
> > +    uint8_t status;
> > +    uint8_t config;
> > +    uint8_t alert_config;
> > +    uint8_t addr;
> > +    qemu_irq alarm;
> > +} SBTSIState;
> > +
> > +/*
> > + * SB-TSI registers only support SMBus byte data access. "_INT" registers
> > are
> > + * the integer part of a temperature value or limit, and "_DEC" registers
> > are
> > + * corresponding decimal parts.
> > + */
> > +#define SBTSI_REG_TEMP_INT      0x01 /* RO */
> > +#define SBTSI_REG_STATUS        0x02 /* RO */
> > +#define SBTSI_REG_CONFIG        0x03 /* RO */
> > +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */
> > +#define SBTSI_REG_TEMP_LOW_INT  0x08 /* RW */
> > +#define SBTSI_REG_CONFIG_WR     0x09 /* RW */
> > +#define SBTSI_REG_TEMP_DEC      0x10 /* RO */
> > +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */
> > +#define SBTSI_REG_TEMP_LOW_DEC  0x14 /* RW */
> > +#define SBTSI_REG_ALERT_CONFIG  0xBF /* RW */
> > +#define SBTSI_REG_MAN           0xFE /* RO */
> > +#define SBTSI_REG_REV           0xFF /* RO */
> > +
> > +#define SBTSI_STATUS_HIGH_ALERT BIT(4)
> > +#define SBTSI_STATUS_LOW_ALERT  BIT(3)
> > +#define SBTSI_CONFIG_ALERT_MASK BIT(7)
> > +#define SBTSI_ALARM_EN          BIT(0)
> > +
> > +#define SBTSI_LIMIT_LOW_DEFAULT (0)
> > +#define SBTSI_LIMIT_HIGH_DEFAULT (560)
> > +#define SBTSI_MAN_DEFAULT (0)
> > +#define SBTSI_REV_DEFAULT (4)
> > +#define SBTSI_ALARM_L "alarm_l"
> > +
> > +/* The temperature we stored are in units of 0.125 degrees. */
> > +#define SBTSI_TEMP_UNIT_IN_MILLIDEGREE 125
> > +
> > +/*
> > + * The integer part and decimal of the temperature both 8 bits.
> > + * Only the top 3 bits of the decimal parts are used.
> > + * So the max temperature is (2^8-1) + (2^3-1)/8 = 255.875 degrees.
> > + */
> > +#define SBTSI_TEMP_MAX 255875
> > +
> > +/* The integer part of the temperature in terms of 0.125 degrees. */
> > +static uint8_t get_temp_int(uint32_t temp)
> > +{
> > +    return temp >> 3;
> > +}
> > +
> > +/*
> > + * The decimal part of the temperature, in terms of 0.125 degrees.
> > + * H/W store it in the top 3 bits so we shift it by 5.
> > + */
> > +static uint8_t get_temp_dec(uint32_t temp)
> > +{
> > +    return (temp & 0x7) << 5;
> > +}
> > +
> > +/*
> > + * Compute the temperature using the integer and decimal part,
> > + * in terms of 0.125 degrees. The decimal part are only the top 3 bits
> > + * so we shift it by 5 here.
> > + */
> > +static uint32_t compute_temp(uint8_t integer, uint8_t decimal)
> > +{
> > +    return (integer << 3) + (decimal >> 5);
> > +}
> > +
> > +/* Compute new temp with new int part of the temperature. */
> > +static uint32_t compute_temp_int(uint32_t temp, uint8_t integer)
> > +{
> > +    return compute_temp(integer, get_temp_dec(temp));
> > +}
> > +
> > +/* Compute new temp with new dec part of the temperature. */
> > +static uint32_t compute_temp_dec(uint32_t temp, uint8_t decimal)
> > +{
> > +    return compute_temp(get_temp_int(temp), decimal);
> > +}
> > +
> > +/* The integer part of the temperature. */
> > +static void sbtsi_update_status(SBTSIState *s)
> > +{
> > +    s->status = 0;
> > +    if (s->alert_config & SBTSI_ALARM_EN) {
> > +        if (s->temperature >= s->limit_high) {
> > +            s->status |= SBTSI_STATUS_HIGH_ALERT;
> > +        }
> > +        if (s->temperature <= s->limit_low) {
> > +            s->status |= SBTSI_STATUS_LOW_ALERT;
> > +        }
> > +    }
> > +}
> > +
> > +static void sbtsi_update_alarm(SBTSIState *s)
> > +{
> > +    sbtsi_update_status(s);
> > +    if (s->status != 0 && !(s->config & SBTSI_CONFIG_ALERT_MASK)) {
> > +        qemu_irq_raise(s->alarm);
> > +    } else {
> > +        qemu_irq_lower(s->alarm);
> > +    }
> > +}
> > +
> > +static uint8_t sbtsi_read_byte(SMBusDevice *d)
> > +{
> > +    SBTSIState *s = SBTSI(d);
> > +    uint8_t data = 0;
> > +
> > +    switch (s->addr) {
> > +    case SBTSI_REG_TEMP_INT:
> > +        data = get_temp_int(s->temperature);
> > +        break;
> > +
> > +    case SBTSI_REG_TEMP_DEC:
> > +        data = get_temp_dec(s->temperature);
> > +        break;
> > +
> > +    case SBTSI_REG_TEMP_HIGH_INT:
> > +        data = get_temp_int(s->limit_high);
> > +        break;
> > +
> > +    case SBTSI_REG_TEMP_LOW_INT:
> > +        data = get_temp_int(s->limit_low);
> > +        break;
> > +
> > +    case SBTSI_REG_TEMP_HIGH_DEC:
> > +        data = get_temp_dec(s->limit_high);
> > +        break;
> > +
> > +    case SBTSI_REG_TEMP_LOW_DEC:
> > +        data = get_temp_dec(s->limit_low);
> > +        break;
> > +
> > +    case SBTSI_REG_CONFIG:
> > +    case SBTSI_REG_CONFIG_WR:
> > +        data = s->config;
> > +        break;
> > +
> > +    case SBTSI_REG_STATUS:
> > +        sbtsi_update_alarm(s);
> > +        data = s->status;
> > +        break;
> > +
> > +    case SBTSI_REG_ALERT_CONFIG:
> > +        data = s->alert_config;
> > +        break;
> > +
> > +    case SBTSI_REG_MAN:
> > +        data = SBTSI_MAN_DEFAULT;
> > +        break;
> > +
> > +    case SBTSI_REG_REV:
> > +        data = SBTSI_REV_DEFAULT;
> > +        break;

Does this device do some sort of auto-increment on the address when
reading/writing?

Other than that possible issue, I don't see anything else, it's pretty
straightforward.

> > +
> > +    default:
> > +        qemu_log_mask(LOG_GUEST_ERROR,
> > +                "%s: reading from invalid reg: 0x%02x\n",
> > +                __func__, s->addr);
> > +        break;
> > +    }
> > +
> > +    trace_tmp_sbtsi_read_data(s->addr, data);
> > +    return data;
> > +}
> > +
> > +static void sbtsi_write(SBTSIState *s, uint8_t data)
> > +{
> > +    trace_tmp_sbtsi_write_data(s->addr, data);
> > +    switch (s->addr) {
> > +    case SBTSI_REG_CONFIG_WR:
> > +        s->config = data;
> > +        break;
> > +
> > +    case SBTSI_REG_TEMP_HIGH_INT:
> > +        s->limit_high = compute_temp_int(s->limit_high, data);
> > +        break;
> > +
> > +    case SBTSI_REG_TEMP_LOW_INT:
> > +        s->limit_low = compute_temp_int(s->limit_low, data);
> > +        break;
> > +
> > +    case SBTSI_REG_TEMP_HIGH_DEC:
> > +        s->limit_high = compute_temp_dec(s->limit_high, data);
> > +        break;
> > +
> > +    case SBTSI_REG_TEMP_LOW_DEC:
> > +        s->limit_low = compute_temp_dec(s->limit_low, data);
> > +        break;
> > +
> > +    case SBTSI_REG_ALERT_CONFIG:
> > +        s->alert_config = data;
> > +        break;
> > +
> > +    case SBTSI_REG_TEMP_INT:
> > +    case SBTSI_REG_TEMP_DEC:
> > +    case SBTSI_REG_CONFIG:
> > +    case SBTSI_REG_STATUS:
> > +    case SBTSI_REG_MAN:
> > +    case SBTSI_REG_REV:
> > +        qemu_log_mask(LOG_GUEST_ERROR,
> > +                "%s: writing to read only reg: 0x%02x data: 0x%02x\n",
> > +                __func__, s->addr, data);
> > +        break;
> > +
> > +    default:
> > +        qemu_log_mask(LOG_GUEST_ERROR,
> > +                "%s: writing to invalid reg: 0x%02x data: 0x%02x\n",
> > +                __func__, s->addr, data);
> > +        break;
> > +    }
> > +    sbtsi_update_alarm(s);
> > +}
> > +
> > +static int sbtsi_write_data(SMBusDevice *d, uint8_t *buf, uint8_t len)
> > +{
> > +    SBTSIState *s = SBTSI(d);
> > +
> > +    if (len == 0) {
> > +        qemu_log_mask(LOG_GUEST_ERROR, "%s: writing empty data\n",
> > __func__);
> > +        return -1;
> > +    }
> > +
> > +    s->addr = buf[0];
> > +    if (len > 1) {
> > +        sbtsi_write(s, buf[1]);
> > +        if (len > 2) {
> > +            qemu_log_mask(LOG_GUEST_ERROR, "%s: extra data at end\n",
> > __func__);
> > +        }
> > +    }
> > +    return 0;
> > +}
> > +
> > +/* Units are millidegrees. */
> > +static void sbtsi_get_temperature(Object *obj, Visitor *v, const char
> > *name,
> > +                                  void *opaque, Error **errp)
> > +{
> > +    SBTSIState *s = SBTSI(obj);
> > +    uint32_t temp = s->temperature * SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
> > +
> > +    visit_type_uint32(v, name, &temp, errp);
> > +}
> > +
> > +/* Units are millidegrees. */
> > +static void sbtsi_set_temperature(Object *obj, Visitor *v, const char
> > *name,
> > +                                  void *opaque, Error **errp)
> > +{
> > +    SBTSIState *s = SBTSI(obj);
> > +    uint32_t temp;
> > +
> > +    if (!visit_type_uint32(v, name, &temp, errp)) {
> > +        return;
> > +    }
> > +    if (temp > SBTSI_TEMP_MAX) {
> > +        error_setg(errp, "value %" PRIu32 ".%03" PRIu32 " C is out of
> > range",
> > +                   temp / 1000, temp % 1000);
> > +        return;
> > +    }
> > +
> > +    s->temperature = temp / SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
> > +    sbtsi_update_alarm(s);
> > +}
> > +
> > +static int sbtsi_post_load(void *opaque, int version_id)
> > +{
> > +    SBTSIState *s = opaque;
> > +
> > +    sbtsi_update_alarm(s);
> > +    return 0;
> > +}
> > +
> > +static const VMStateDescription vmstate_sbtsi = {
> > +    .name = "SBTSI",
> > +    .version_id = 0,
> > +    .minimum_version_id = 0,
> > +    .post_load = sbtsi_post_load,
> > +    .fields = (VMStateField[]) {
> > +        VMSTATE_UINT32(temperature, SBTSIState),
> > +        VMSTATE_UINT32(limit_low, SBTSIState),
> > +        VMSTATE_UINT32(limit_high, SBTSIState),
> > +        VMSTATE_UINT8(config, SBTSIState),
> > +        VMSTATE_UINT8(status, SBTSIState),
> > +        VMSTATE_UINT8(addr, SBTSIState),
> > +        VMSTATE_END_OF_LIST()
> > +    }
> > +};
> > +
> > +static void sbtsi_enter_reset(Object *obj, ResetType type)
> > +{
> > +    SBTSIState *s = SBTSI(obj);
> > +
> > +    s->config = 0;
> > +    s->limit_low = SBTSI_LIMIT_LOW_DEFAULT;
> > +    s->limit_high = SBTSI_LIMIT_HIGH_DEFAULT;
> > +}
> > +
> > +static void sbtsi_hold_reset(Object *obj)
> > +{
> > +    SBTSIState *s = SBTSI(obj);
> > +
> > +    qemu_irq_lower(s->alarm);
> > +}
> > +
> > +static void sbtsi_init(Object *obj)
> > +{
> > +    SBTSIState *s = SBTSI(obj);
> > +
> > +    /* Current temperature in millidegrees. */
> > +    object_property_add(obj, "temperature", "uint32",
> > +                        sbtsi_get_temperature, sbtsi_set_temperature,
> > +                        NULL, NULL);
> > +    qdev_init_gpio_out_named(DEVICE(obj), &s->alarm, SBTSI_ALARM_L, 0);
> > +}
> > +
> > +static void sbtsi_class_init(ObjectClass *klass, void *data)
> > +{
> > +    ResettableClass *rc = RESETTABLE_CLASS(klass);
> > +    DeviceClass *dc = DEVICE_CLASS(klass);
> > +    SMBusDeviceClass *k = SMBUS_DEVICE_CLASS(klass);
> > +
> > +    dc->desc = "SB-TSI Temperature Sensor";
> > +    dc->vmsd = &vmstate_sbtsi;
> > +    k->write_data = sbtsi_write_data;
> > +    k->receive_byte = sbtsi_read_byte;
> > +    rc->phases.enter = sbtsi_enter_reset;
> > +    rc->phases.hold = sbtsi_hold_reset;
> > +}
> > +
> > +static const TypeInfo sbtsi_info = {
> > +    .name          = TYPE_SBTSI,
> > +    .parent        = TYPE_SMBUS_DEVICE,
> > +    .instance_size = sizeof(SBTSIState),
> > +    .instance_init = sbtsi_init,
> > +    .class_init    = sbtsi_class_init,
> > +};
> > +
> > +static void sbtsi_register_types(void)
> > +{
> > +    type_register_static(&sbtsi_info);
> > +}
> > +
> > +type_init(sbtsi_register_types)
> > diff --git a/hw/sensor/trace-events b/hw/sensor/trace-events
> > new file mode 100644
> > index 0000000000..21ab3809e2
> > --- /dev/null
> > +++ b/hw/sensor/trace-events
> > @@ -0,0 +1,5 @@
> > +# See docs/devel/tracing.rst for syntax documentation.
> > +
> > +# tmp_sbtsi.c
> > +tmp_sbtsi_write_data(uint8_t addr, uint8_t value) "SBTSI write
> > addr:0x%02x data: 0x%02x"
> > +tmp_sbtsi_read_data(uint8_t addr, uint8_t value) "SBTSI read addr:0x%02x
> > data: 0x%02x"
> > diff --git a/hw/sensor/trace.h b/hw/sensor/trace.h
> > new file mode 100644
> > index 0000000000..e4721560b0
> > --- /dev/null
> > +++ b/hw/sensor/trace.h
> > @@ -0,0 +1 @@
> > +#include "trace/trace-hw_sensor.h"
> > diff --git a/meson.build b/meson.build
> > index 53065e96ec..f8ab0bf74e 100644
> > --- a/meson.build
> > +++ b/meson.build
> > @@ -2494,6 +2494,7 @@ if have_system
> >      'hw/rtc',
> >      'hw/s390x',
> >      'hw/scsi',
> > +    'hw/sensor',
> >      'hw/sd',
> >      'hw/sh4',
> >      'hw/sparc',
> > diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
> > index 37e1eaa449..d1a8c38f74 100644
> > --- a/tests/qtest/meson.build
> > +++ b/tests/qtest/meson.build
> > @@ -254,6 +254,7 @@ qos_test_ss.add(
> >    'spapr-phb-test.c',
> >    'tmp105-test.c',
> >    'emc141x-test.c',
> > +  'tmp_sbtsi-test.c',
> >    'usb-hcd-ohci-test.c',
> >    'virtio-test.c',
> >    'virtio-blk-test.c',
> > diff --git a/tests/qtest/tmp_sbtsi-test.c b/tests/qtest/tmp_sbtsi-test.c
> > new file mode 100644
> > index 0000000000..7f5fafacc7
> > --- /dev/null
> > +++ b/tests/qtest/tmp_sbtsi-test.c
> > @@ -0,0 +1,180 @@
> > +/*
> > + * QTests for the SBTSI temperature sensor
> > + *
> > + * Copyright 2020 Google LLC
> > + *
> > + * This program is free software; you can redistribute it and/or modify it
> > + * under the terms of the GNU General Public License as published by the
> > + * Free Software Foundation; either version 2 of the License, or
> > + * (at your option) any later version.
> > + *
> > + * This program is distributed in the hope that it will be useful, but
> > WITHOUT
> > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
> > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
> > + * for more details.
> > + */
> > +
> > +#include "qemu/osdep.h"
> > +
> > +#include "libqtest-single.h"
> > +#include "libqos/qgraph.h"
> > +#include "libqos/i2c.h"
> > +#include "qapi/qmp/qdict.h"
> > +#include "qemu/bitops.h"
> > +
> > +#define TEST_ID   "sbtsi-test"
> > +#define TEST_ADDR (0x4c)
> > +
> > +/*
> > + * SB-TSI registers only support SMBus byte data access. "_INT" registers
> > are
> > + * the integer part of a temperature value or limit, and "_DEC" registers
> > are
> > + * corresponding decimal parts.
> > + */
> > +#define REG_TEMP_INT      0x01 /* RO */
> > +#define REG_STATUS        0x02 /* RO */
> > +#define REG_CONFIG        0x03 /* RO */
> > +#define REG_TEMP_HIGH_INT 0x07 /* RW */
> > +#define REG_TEMP_LOW_INT  0x08 /* RW */
> > +#define REG_CONFIG_WR     0x09 /* RW */
> > +#define REG_TEMP_DEC      0x10 /* RO */
> > +#define REG_TEMP_HIGH_DEC 0x13 /* RW */
> > +#define REG_TEMP_LOW_DEC  0x14 /* RW */
> > +#define REG_ALERT_CONFIG  0xBF /* RW */
> > +
> > +#define STATUS_HIGH_ALERT BIT(4)
> > +#define STATUS_LOW_ALERT  BIT(3)
> > +#define CONFIG_ALERT_MASK BIT(7)
> > +#define ALARM_EN          BIT(0)
> > +
> > +/* The temperature stored are in units of 0.125 degrees. */
> > +#define TEMP_UNIT_IN_MILLIDEGREE 125
> > +#define LIMIT_LOW (10500)
> > +#define LIMIT_HIGH (55125)
> > +
> > +static uint32_t qmp_sbtsi_get_temperature(const char *id)
> > +{
> > +    QDict *response;
> > +    int ret;
> > +
> > +    response = qmp("{ 'execute': 'qom-get', 'arguments': { 'path': %s, "
> > +                   "'property': 'temperature' } }", id);
> > +    g_assert(qdict_haskey(response, "return"));
> > +    ret = (uint32_t)qdict_get_int(response, "return");
> > +    qobject_unref(response);
> > +    return ret;
> > +}
> > +
> > +static void qmp_sbtsi_set_temperature(const char *id, uint32_t value)
> > +{
> > +    QDict *response;
> > +
> > +    response = qmp("{ 'execute': 'qom-set', 'arguments': { 'path': %s, "
> > +                   "'property': 'temperature', 'value': %d } }", id,
> > value);
> > +    g_assert(qdict_haskey(response, "return"));
> > +    qobject_unref(response);
> > +}
> > +
> > +/*
> > + * Compute the temperature using the integer and decimal part and return
> > + * millidegrees. The decimal part are only the top 3 bits so we shift it
> > by
> > + * 5 here.
> > + */
> > +static uint32_t regs_to_temp(uint8_t integer, uint8_t decimal)
> > +{
> > +    return ((integer << 3) + (decimal >> 5)) * TEMP_UNIT_IN_MILLIDEGREE;
> > +}
> > +
> > +/*
> > + * Compute the integer and decimal parts of the temperature in
> > millidegrees.
> > + * H/W store the decimal in the top 3 bits so we shift it by 5.
> > + */
> > +static void temp_to_regs(uint32_t temp, uint8_t *integer, uint8_t
> > *decimal)
> > +{
> > +    temp /= TEMP_UNIT_IN_MILLIDEGREE;
> > +    *integer = temp >> 3;
> > +    *decimal = (temp & 0x7) << 5;
> > +}
> > +
> > +static void tx_rx(void *obj, void *data, QGuestAllocator *alloc)
> > +{
> > +    uint16_t value;
> > +    uint8_t integer, decimal;
> > +    QI2CDevice *i2cdev = (QI2CDevice *)obj;
> > +
> > +    /* Test default values */
> > +    value = qmp_sbtsi_get_temperature(TEST_ID);
> > +    g_assert_cmpuint(value, ==, 0);
> > +
> > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
> > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
> > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 0);
> > +
> > +    /* Test setting temperature */
> > +    qmp_sbtsi_set_temperature(TEST_ID, 20000);
> > +    value = qmp_sbtsi_get_temperature(TEST_ID);
> > +    g_assert_cmpuint(value, ==, 20000);
> > +
> > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
> > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
> > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 20000);
> > +
> > +    /* Set alert mask in config */
> > +    i2c_set8(i2cdev, REG_CONFIG_WR, CONFIG_ALERT_MASK);
> > +    value = i2c_get8(i2cdev, REG_CONFIG);
> > +    g_assert_cmphex(value, ==, CONFIG_ALERT_MASK);
> > +    /* Enable alarm_en */
> > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, ALARM_EN);
> > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
> > +    g_assert_cmphex(value, ==, ALARM_EN);
> > +
> > +    /* Test setting limits */
> > +    /* Limit low = 10.500 */
> > +    temp_to_regs(LIMIT_LOW, &integer, &decimal);
> > +    i2c_set8(i2cdev, REG_TEMP_LOW_INT, integer);
> > +    i2c_set8(i2cdev, REG_TEMP_LOW_DEC, decimal);
> > +    integer = i2c_get8(i2cdev, REG_TEMP_LOW_INT);
> > +    decimal = i2c_get8(i2cdev, REG_TEMP_LOW_DEC);
> > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, LIMIT_LOW);
> > +    /* Limit high = 55.125 */
> > +    temp_to_regs(LIMIT_HIGH, &integer, &decimal);
> > +    i2c_set8(i2cdev, REG_TEMP_HIGH_INT, integer);
> > +    i2c_set8(i2cdev, REG_TEMP_HIGH_DEC, decimal);
> > +    integer = i2c_get8(i2cdev, REG_TEMP_HIGH_INT);
> > +    decimal = i2c_get8(i2cdev, REG_TEMP_HIGH_DEC);
> > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, LIMIT_HIGH);
> > +    /* No alert is generated. */
> > +    value = i2c_get8(i2cdev, REG_STATUS);
> > +    g_assert_cmphex(value, ==, 0);
> > +
> > +    /* Test alert for low temperature */
> > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_LOW);
> > +    value = i2c_get8(i2cdev, REG_STATUS);
> > +    g_assert_cmphex(value, ==, STATUS_LOW_ALERT);
> > +
> > +    /* Test alert for high temperature */
> > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_HIGH);
> > +    value = i2c_get8(i2cdev, REG_STATUS);
> > +    g_assert_cmphex(value, ==, STATUS_HIGH_ALERT);
> > +
> > +    /* Disable alarm_en */
> > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, 0);
> > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
> > +    g_assert_cmphex(value, ==, 0);
> > +    /* No alert when alarm_en is false. */
> > +    value = i2c_get8(i2cdev, REG_STATUS);
> > +    g_assert_cmphex(value, ==, 0);
> > +}
> > +
> > +static void sbtsi_register_nodes(void)
> > +{
> > +    QOSGraphEdgeOptions opts = {
> > +        .extra_device_opts = "id=" TEST_ID ",address=0x4c"
> > +    };
> > +    add_qi2c_address(&opts, &(QI2CAddress) { TEST_ADDR });
> > +
> > +    qos_node_create_driver("sbtsi", i2c_device_create);
> > +    qos_node_consumes("sbtsi", "i2c-bus", &opts);
> > +
> > +    qos_add_test("tx-rx", "sbtsi", tx_rx, NULL);
> > +}
> > +libqos_init(sbtsi_register_nodes);
> > --
> 
> 
> + Corey for i2c maintainer.  The new sensor directory is mostly if not
> entirely i2c devices.  I didn't create a maintainer entry for this i2c
> device, but I can if desired and send out a v2.

Yeah, I guess I should be maintainer there.  I'll queue up a change for
that.  Thanks.

-corey

> 
> 
> > 2.34.1.575.g55b058a8bb-goog
> >
> >

Patrick Leis Jan. 18, 2022, 5:10 p.m. UTC | #8

On Mon, Jan 17, 2022 at 6:05 AM Corey Minyard <[e-mail]> wrote:

> On Sun, Jan 09, 2022 at 06:17:34PM -0800, Patrick Venture wrote:
> > On Fri, Jan 7, 2022 at 7:04 PM Patrick Venture <[e-mail]>
> wrote:
> >
> > > From: Hao Wu <[e-mail]>
> > >
> > > SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
> > > interface that reports AMD SoC's Ttcl (normalized temperature),
> > > and resembles a typical 8-pin remote temperature sensor's I2C interface
> > > to BMC.
> > >
> > > This patch implements a basic AMD SB-TSI sensor that is
> > > compatible with the open-source data sheet from AMD and Linux
> > > kernel driver.
> > >
> > > Reference:
> > > Linux kernel driver:
> > > https://lkml.org/lkml/2020/12/11/968
> > > Register Map:
> > > https://developer.amd.com/wp-content/resources/56255_3_03.PDF
> > > (Chapter 6)
> > >
> > > Signed-off-by: Hao Wu <[e-mail]>
> > > Reviewed-by: Doug Evans <[e-mail]>
> > > ---
> > >  hw/sensor/Kconfig            |   4 +
> > >  hw/sensor/meson.build        |   1 +
> > >  hw/sensor/tmp_sbtsi.c        | 393 +++++++++++++++++++++++++++++++++++
> > >  hw/sensor/trace-events       |   5 +
> > >  hw/sensor/trace.h            |   1 +
> > >  meson.build                  |   1 +
> > >  tests/qtest/meson.build      |   1 +
> > >  tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++
> > >  8 files changed, 586 insertions(+)
> > >  create mode 100644 hw/sensor/tmp_sbtsi.c
> > >  create mode 100644 hw/sensor/trace-events
> > >  create mode 100644 hw/sensor/trace.h
> > >  create mode 100644 tests/qtest/tmp_sbtsi-test.c
> > >
> > > diff --git a/hw/sensor/Kconfig b/hw/sensor/Kconfig
> > > index 9c8a049b06..27f6f79c84 100644
> > > --- a/hw/sensor/Kconfig
> > > +++ b/hw/sensor/Kconfig
> > > @@ -21,3 +21,7 @@ config ADM1272
> > >  config MAX34451
> > >      bool
> > >      depends on I2C
> > > +
> > > +config AMDSBTSI
> > > +    bool
> > > +    depends on I2C
> > > diff --git a/hw/sensor/meson.build b/hw/sensor/meson.build
> > > index 059c4ca935..f7b0e645eb 100644
> > > --- a/hw/sensor/meson.build
> > > +++ b/hw/sensor/meson.build
> > > @@ -4,3 +4,4 @@ softmmu_ss.add(when: 'CONFIG_DPS310', if_true:
> > > files('dps310.c'))
> > >  softmmu_ss.add(when: 'CONFIG_EMC141X', if_true: files('emc141x.c'))
> > >  softmmu_ss.add(when: 'CONFIG_ADM1272', if_true: files('adm1272.c'))
> > >  softmmu_ss.add(when: 'CONFIG_MAX34451', if_true: files('max34451.c'))
> > > +softmmu_ss.add(when: 'CONFIG_AMDSBTSI', if_true: files('tmp_sbtsi.c'))
> > > diff --git a/hw/sensor/tmp_sbtsi.c b/hw/sensor/tmp_sbtsi.c
> > > new file mode 100644
> > > index 0000000000..b68c7ebf61
> > > --- /dev/null
> > > +++ b/hw/sensor/tmp_sbtsi.c
> > > @@ -0,0 +1,393 @@
> > > +/*
> > > + * AMD SBI Temperature Sensor Interface (SB-TSI)
> > > + *
> > > + * Copyright 2021 Google LLC
> > > + *
> > > + * This program is free software; you can redistribute it and/or
> modify it
> > > + * under the terms of the GNU General Public License as published by
> the
> > > + * Free Software Foundation; either version 2 of the License, or
> > > + * (at your option) any later version.
> > > + *
> > > + * This program is distributed in the hope that it will be useful, but
> > > WITHOUT
> > > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
> or
> > > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
> License
> > > + * for more details.
> > > + */
> > > +
> > > +#include "qemu/osdep.h"
> > > +#include "hw/i2c/smbus_slave.h"
> > > +#include "hw/irq.h"
> > > +#include "migration/vmstate.h"
> > > +#include "qapi/error.h"
> > > +#include "qapi/visitor.h"
> > > +#include "qemu/log.h"
> > > +#include "qemu/module.h"
> > > +#include "trace.h"
> > > +
> > > +#define TYPE_SBTSI "sbtsi"
> > > +#define SBTSI(obj) OBJECT_CHECK(SBTSIState, (obj), TYPE_SBTSI)
> > > +
> > > +/**
> > > + * SBTSIState:
> > > + * temperatures are in units of 0.125 degrees
> > > + * @temperature: Temperature
> > > + * @limit_low: Lowest temperature
> > > + * @limit_high: Highest temperature
> > > + * @status: The status register
> > > + * @config: The config register
> > > + * @alert_config: The config for alarm_l output.
> > > + * @addr: The address to read/write for the next cmd.
> > > + * @alarm: The alarm_l output pin (GPIO)
> > > + */
> > > +typedef struct SBTSIState {
> > > +    SMBusDevice parent;
> > > +
> > > +    uint32_t temperature;
> > > +    uint32_t limit_low;
> > > +    uint32_t limit_high;
> > > +    uint8_t status;
> > > +    uint8_t config;
> > > +    uint8_t alert_config;
> > > +    uint8_t addr;
> > > +    qemu_irq alarm;
> > > +} SBTSIState;
> > > +
> > > +/*
> > > + * SB-TSI registers only support SMBus byte data access. "_INT"
> registers
> > > are
> > > + * the integer part of a temperature value or limit, and "_DEC"
> registers
> > > are
> > > + * corresponding decimal parts.
> > > + */
> > > +#define SBTSI_REG_TEMP_INT      0x01 /* RO */
> > > +#define SBTSI_REG_STATUS        0x02 /* RO */
> > > +#define SBTSI_REG_CONFIG        0x03 /* RO */
> > > +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */
> > > +#define SBTSI_REG_TEMP_LOW_INT  0x08 /* RW */
> > > +#define SBTSI_REG_CONFIG_WR     0x09 /* RW */
> > > +#define SBTSI_REG_TEMP_DEC      0x10 /* RO */
> > > +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */
> > > +#define SBTSI_REG_TEMP_LOW_DEC  0x14 /* RW */
> > > +#define SBTSI_REG_ALERT_CONFIG  0xBF /* RW */
> > > +#define SBTSI_REG_MAN           0xFE /* RO */
> > > +#define SBTSI_REG_REV           0xFF /* RO */
> > > +
> > > +#define SBTSI_STATUS_HIGH_ALERT BIT(4)
> > > +#define SBTSI_STATUS_LOW_ALERT  BIT(3)
> > > +#define SBTSI_CONFIG_ALERT_MASK BIT(7)
> > > +#define SBTSI_ALARM_EN          BIT(0)
> > > +
> > > +#define SBTSI_LIMIT_LOW_DEFAULT (0)
> > > +#define SBTSI_LIMIT_HIGH_DEFAULT (560)
> > > +#define SBTSI_MAN_DEFAULT (0)
> > > +#define SBTSI_REV_DEFAULT (4)
> > > +#define SBTSI_ALARM_L "alarm_l"
> > > +
> > > +/* The temperature we stored are in units of 0.125 degrees. */
> > > +#define SBTSI_TEMP_UNIT_IN_MILLIDEGREE 125
> > > +
> > > +/*
> > > + * The integer part and decimal of the temperature both 8 bits.
> > > + * Only the top 3 bits of the decimal parts are used.
> > > + * So the max temperature is (2^8-1) + (2^3-1)/8 = 255.875 degrees.
> > > + */
> > > +#define SBTSI_TEMP_MAX 255875
> > > +
> > > +/* The integer part of the temperature in terms of 0.125 degrees. */
> > > +static uint8_t get_temp_int(uint32_t temp)
> > > +{
> > > +    return temp >> 3;
> > > +}
> > > +
> > > +/*
> > > + * The decimal part of the temperature, in terms of 0.125 degrees.
> > > + * H/W store it in the top 3 bits so we shift it by 5.
> > > + */
> > > +static uint8_t get_temp_dec(uint32_t temp)
> > > +{
> > > +    return (temp & 0x7) << 5;
> > > +}
> > > +
> > > +/*
> > > + * Compute the temperature using the integer and decimal part,
> > > + * in terms of 0.125 degrees. The decimal part are only the top 3 bits
> > > + * so we shift it by 5 here.
> > > + */
> > > +static uint32_t compute_temp(uint8_t integer, uint8_t decimal)
> > > +{
> > > +    return (integer << 3) + (decimal >> 5);
> > > +}
> > > +
> > > +/* Compute new temp with new int part of the temperature. */
> > > +static uint32_t compute_temp_int(uint32_t temp, uint8_t integer)
> > > +{
> > > +    return compute_temp(integer, get_temp_dec(temp));
> > > +}
> > > +
> > > +/* Compute new temp with new dec part of the temperature. */
> > > +static uint32_t compute_temp_dec(uint32_t temp, uint8_t decimal)
> > > +{
> > > +    return compute_temp(get_temp_int(temp), decimal);
> > > +}
> > > +
> > > +/* The integer part of the temperature. */
> > > +static void sbtsi_update_status(SBTSIState *s)
> > > +{
> > > +    s->status = 0;
> > > +    if (s->alert_config & SBTSI_ALARM_EN) {
> > > +        if (s->temperature >= s->limit_high) {
> > > +            s->status |= SBTSI_STATUS_HIGH_ALERT;
> > > +        }
> > > +        if (s->temperature <= s->limit_low) {
> > > +            s->status |= SBTSI_STATUS_LOW_ALERT;
> > > +        }
> > > +    }
> > > +}
> > > +
> > > +static void sbtsi_update_alarm(SBTSIState *s)
> > > +{
> > > +    sbtsi_update_status(s);
> > > +    if (s->status != 0 && !(s->config & SBTSI_CONFIG_ALERT_MASK)) {
> > > +        qemu_irq_raise(s->alarm);
> > > +    } else {
> > > +        qemu_irq_lower(s->alarm);
> > > +    }
> > > +}
> > > +
> > > +static uint8_t sbtsi_read_byte(SMBusDevice *d)
> > > +{
> > > +    SBTSIState *s = SBTSI(d);
> > > +    uint8_t data = 0;
> > > +
> > > +    switch (s->addr) {
> > > +    case SBTSI_REG_TEMP_INT:
> > > +        data = get_temp_int(s->temperature);
> > > +        break;
> > > +
> > > +    case SBTSI_REG_TEMP_DEC:
> > > +        data = get_temp_dec(s->temperature);
> > > +        break;
> > > +
> > > +    case SBTSI_REG_TEMP_HIGH_INT:
> > > +        data = get_temp_int(s->limit_high);
> > > +        break;
> > > +
> > > +    case SBTSI_REG_TEMP_LOW_INT:
> > > +        data = get_temp_int(s->limit_low);
> > > +        break;
> > > +
> > > +    case SBTSI_REG_TEMP_HIGH_DEC:
> > > +        data = get_temp_dec(s->limit_high);
> > > +        break;
> > > +
> > > +    case SBTSI_REG_TEMP_LOW_DEC:
> > > +        data = get_temp_dec(s->limit_low);
> > > +        break;
> > > +
> > > +    case SBTSI_REG_CONFIG:
> > > +    case SBTSI_REG_CONFIG_WR:
> > > +        data = s->config;
> > > +        break;
> > > +
> > > +    case SBTSI_REG_STATUS:
> > > +        sbtsi_update_alarm(s);
> > > +        data = s->status;
> > > +        break;
> > > +
> > > +    case SBTSI_REG_ALERT_CONFIG:
> > > +        data = s->alert_config;
> > > +        break;
> > > +
> > > +    case SBTSI_REG_MAN:
> > > +        data = SBTSI_MAN_DEFAULT;
> > > +        break;
> > > +
> > > +    case SBTSI_REG_REV:
> > > +        data = SBTSI_REV_DEFAULT;
> > > +        break;
>
> Does this device do some sort of auto-increment on the address when
> reading/writing?
>

+Hao Wu <[e-mail]>   - Please take a look at the above
question.  I imagine it's a while since you've thought about it, but please
double check :)
Thanks!


> Other than that possible issue, I don't see anything else, it's pretty
> straightforward.
>
> > > +
> > > +    default:
> > > +        qemu_log_mask(LOG_GUEST_ERROR,
> > > +                "%s: reading from invalid reg: 0x%02x\n",
> > > +                __func__, s->addr);
> > > +        break;
> > > +    }
> > > +
> > > +    trace_tmp_sbtsi_read_data(s->addr, data);
> > > +    return data;
> > > +}
> > > +
> > > +static void sbtsi_write(SBTSIState *s, uint8_t data)
> > > +{
> > > +    trace_tmp_sbtsi_write_data(s->addr, data);
> > > +    switch (s->addr) {
> > > +    case SBTSI_REG_CONFIG_WR:
> > > +        s->config = data;
> > > +        break;
> > > +
> > > +    case SBTSI_REG_TEMP_HIGH_INT:
> > > +        s->limit_high = compute_temp_int(s->limit_high, data);
> > > +        break;
> > > +
> > > +    case SBTSI_REG_TEMP_LOW_INT:
> > > +        s->limit_low = compute_temp_int(s->limit_low, data);
> > > +        break;
> > > +
> > > +    case SBTSI_REG_TEMP_HIGH_DEC:
> > > +        s->limit_high = compute_temp_dec(s->limit_high, data);
> > > +        break;
> > > +
> > > +    case SBTSI_REG_TEMP_LOW_DEC:
> > > +        s->limit_low = compute_temp_dec(s->limit_low, data);
> > > +        break;
> > > +
> > > +    case SBTSI_REG_ALERT_CONFIG:
> > > +        s->alert_config = data;
> > > +        break;
> > > +
> > > +    case SBTSI_REG_TEMP_INT:
> > > +    case SBTSI_REG_TEMP_DEC:
> > > +    case SBTSI_REG_CONFIG:
> > > +    case SBTSI_REG_STATUS:
> > > +    case SBTSI_REG_MAN:
> > > +    case SBTSI_REG_REV:
> > > +        qemu_log_mask(LOG_GUEST_ERROR,
> > > +                "%s: writing to read only reg: 0x%02x data: 0x%02x\n",
> > > +                __func__, s->addr, data);
> > > +        break;
> > > +
> > > +    default:
> > > +        qemu_log_mask(LOG_GUEST_ERROR,
> > > +                "%s: writing to invalid reg: 0x%02x data: 0x%02x\n",
> > > +                __func__, s->addr, data);
> > > +        break;
> > > +    }
> > > +    sbtsi_update_alarm(s);
> > > +}
> > > +
> > > +static int sbtsi_write_data(SMBusDevice *d, uint8_t *buf, uint8_t len)
> > > +{
> > > +    SBTSIState *s = SBTSI(d);
> > > +
> > > +    if (len == 0) {
> > > +        qemu_log_mask(LOG_GUEST_ERROR, "%s: writing empty data\n",
> > > __func__);
> > > +        return -1;
> > > +    }
> > > +
> > > +    s->addr = buf[0];
> > > +    if (len > 1) {
> > > +        sbtsi_write(s, buf[1]);
> > > +        if (len > 2) {
> > > +            qemu_log_mask(LOG_GUEST_ERROR, "%s: extra data at end\n",
> > > __func__);
> > > +        }
> > > +    }
> > > +    return 0;
> > > +}
> > > +
> > > +/* Units are millidegrees. */
> > > +static void sbtsi_get_temperature(Object *obj, Visitor *v, const char
> > > *name,
> > > +                                  void *opaque, Error **errp)
> > > +{
> > > +    SBTSIState *s = SBTSI(obj);
> > > +    uint32_t temp = s->temperature * SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
> > > +
> > > +    visit_type_uint32(v, name, &temp, errp);
> > > +}
> > > +
> > > +/* Units are millidegrees. */
> > > +static void sbtsi_set_temperature(Object *obj, Visitor *v, const char
> > > *name,
> > > +                                  void *opaque, Error **errp)
> > > +{
> > > +    SBTSIState *s = SBTSI(obj);
> > > +    uint32_t temp;
> > > +
> > > +    if (!visit_type_uint32(v, name, &temp, errp)) {
> > > +        return;
> > > +    }
> > > +    if (temp > SBTSI_TEMP_MAX) {
> > > +        error_setg(errp, "value %" PRIu32 ".%03" PRIu32 " C is out of
> > > range",
> > > +                   temp / 1000, temp % 1000);
> > > +        return;
> > > +    }
> > > +
> > > +    s->temperature = temp / SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
> > > +    sbtsi_update_alarm(s);
> > > +}
> > > +
> > > +static int sbtsi_post_load(void *opaque, int version_id)
> > > +{
> > > +    SBTSIState *s = opaque;
> > > +
> > > +    sbtsi_update_alarm(s);
> > > +    return 0;
> > > +}
> > > +
> > > +static const VMStateDescription vmstate_sbtsi = {
> > > +    .name = "SBTSI",
> > > +    .version_id = 0,
> > > +    .minimum_version_id = 0,
> > > +    .post_load = sbtsi_post_load,
> > > +    .fields = (VMStateField[]) {
> > > +        VMSTATE_UINT32(temperature, SBTSIState),
> > > +        VMSTATE_UINT32(limit_low, SBTSIState),
> > > +        VMSTATE_UINT32(limit_high, SBTSIState),
> > > +        VMSTATE_UINT8(config, SBTSIState),
> > > +        VMSTATE_UINT8(status, SBTSIState),
> > > +        VMSTATE_UINT8(addr, SBTSIState),
> > > +        VMSTATE_END_OF_LIST()
> > > +    }
> > > +};
> > > +
> > > +static void sbtsi_enter_reset(Object *obj, ResetType type)
> > > +{
> > > +    SBTSIState *s = SBTSI(obj);
> > > +
> > > +    s->config = 0;
> > > +    s->limit_low = SBTSI_LIMIT_LOW_DEFAULT;
> > > +    s->limit_high = SBTSI_LIMIT_HIGH_DEFAULT;
> > > +}
> > > +
> > > +static void sbtsi_hold_reset(Object *obj)
> > > +{
> > > +    SBTSIState *s = SBTSI(obj);
> > > +
> > > +    qemu_irq_lower(s->alarm);
> > > +}
> > > +
> > > +static void sbtsi_init(Object *obj)
> > > +{
> > > +    SBTSIState *s = SBTSI(obj);
> > > +
> > > +    /* Current temperature in millidegrees. */
> > > +    object_property_add(obj, "temperature", "uint32",
> > > +                        sbtsi_get_temperature, sbtsi_set_temperature,
> > > +                        NULL, NULL);
> > > +    qdev_init_gpio_out_named(DEVICE(obj), &s->alarm, SBTSI_ALARM_L,
> 0);
> > > +}
> > > +
> > > +static void sbtsi_class_init(ObjectClass *klass, void *data)
> > > +{
> > > +    ResettableClass *rc = RESETTABLE_CLASS(klass);
> > > +    DeviceClass *dc = DEVICE_CLASS(klass);
> > > +    SMBusDeviceClass *k = SMBUS_DEVICE_CLASS(klass);
> > > +
> > > +    dc->desc = "SB-TSI Temperature Sensor";
> > > +    dc->vmsd = &vmstate_sbtsi;
> > > +    k->write_data = sbtsi_write_data;
> > > +    k->receive_byte = sbtsi_read_byte;
> > > +    rc->phases.enter = sbtsi_enter_reset;
> > > +    rc->phases.hold = sbtsi_hold_reset;
> > > +}
> > > +
> > > +static const TypeInfo sbtsi_info = {
> > > +    .name          = TYPE_SBTSI,
> > > +    .parent        = TYPE_SMBUS_DEVICE,
> > > +    .instance_size = sizeof(SBTSIState),
> > > +    .instance_init = sbtsi_init,
> > > +    .class_init    = sbtsi_class_init,
> > > +};
> > > +
> > > +static void sbtsi_register_types(void)
> > > +{
> > > +    type_register_static(&sbtsi_info);
> > > +}
> > > +
> > > +type_init(sbtsi_register_types)
> > > diff --git a/hw/sensor/trace-events b/hw/sensor/trace-events
> > > new file mode 100644
> > > index 0000000000..21ab3809e2
> > > --- /dev/null
> > > +++ b/hw/sensor/trace-events
> > > @@ -0,0 +1,5 @@
> > > +# See docs/devel/tracing.rst for syntax documentation.
> > > +
> > > +# tmp_sbtsi.c
> > > +tmp_sbtsi_write_data(uint8_t addr, uint8_t value) "SBTSI write
> > > addr:0x%02x data: 0x%02x"
> > > +tmp_sbtsi_read_data(uint8_t addr, uint8_t value) "SBTSI read
> addr:0x%02x
> > > data: 0x%02x"
> > > diff --git a/hw/sensor/trace.h b/hw/sensor/trace.h
> > > new file mode 100644
> > > index 0000000000..e4721560b0
> > > --- /dev/null
> > > +++ b/hw/sensor/trace.h
> > > @@ -0,0 +1 @@
> > > +#include "trace/trace-hw_sensor.h"
> > > diff --git a/meson.build b/meson.build
> > > index 53065e96ec..f8ab0bf74e 100644
> > > --- a/meson.build
> > > +++ b/meson.build
> > > @@ -2494,6 +2494,7 @@ if have_system
> > >      'hw/rtc',
> > >      'hw/s390x',
> > >      'hw/scsi',
> > > +    'hw/sensor',
> > >      'hw/sd',
> > >      'hw/sh4',
> > >      'hw/sparc',
> > > diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
> > > index 37e1eaa449..d1a8c38f74 100644
> > > --- a/tests/qtest/meson.build
> > > +++ b/tests/qtest/meson.build
> > > @@ -254,6 +254,7 @@ qos_test_ss.add(
> > >    'spapr-phb-test.c',
> > >    'tmp105-test.c',
> > >    'emc141x-test.c',
> > > +  'tmp_sbtsi-test.c',
> > >    'usb-hcd-ohci-test.c',
> > >    'virtio-test.c',
> > >    'virtio-blk-test.c',
> > > diff --git a/tests/qtest/tmp_sbtsi-test.c
> b/tests/qtest/tmp_sbtsi-test.c
> > > new file mode 100644
> > > index 0000000000..7f5fafacc7
> > > --- /dev/null
> > > +++ b/tests/qtest/tmp_sbtsi-test.c
> > > @@ -0,0 +1,180 @@
> > > +/*
> > > + * QTests for the SBTSI temperature sensor
> > > + *
> > > + * Copyright 2020 Google LLC
> > > + *
> > > + * This program is free software; you can redistribute it and/or
> modify it
> > > + * under the terms of the GNU General Public License as published by
> the
> > > + * Free Software Foundation; either version 2 of the License, or
> > > + * (at your option) any later version.
> > > + *
> > > + * This program is distributed in the hope that it will be useful, but
> > > WITHOUT
> > > + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
> or
> > > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
> License
> > > + * for more details.
> > > + */
> > > +
> > > +#include "qemu/osdep.h"
> > > +
> > > +#include "libqtest-single.h"
> > > +#include "libqos/qgraph.h"
> > > +#include "libqos/i2c.h"
> > > +#include "qapi/qmp/qdict.h"
> > > +#include "qemu/bitops.h"
> > > +
> > > +#define TEST_ID   "sbtsi-test"
> > > +#define TEST_ADDR (0x4c)
> > > +
> > > +/*
> > > + * SB-TSI registers only support SMBus byte data access. "_INT"
> registers
> > > are
> > > + * the integer part of a temperature value or limit, and "_DEC"
> registers
> > > are
> > > + * corresponding decimal parts.
> > > + */
> > > +#define REG_TEMP_INT      0x01 /* RO */
> > > +#define REG_STATUS        0x02 /* RO */
> > > +#define REG_CONFIG        0x03 /* RO */
> > > +#define REG_TEMP_HIGH_INT 0x07 /* RW */
> > > +#define REG_TEMP_LOW_INT  0x08 /* RW */
> > > +#define REG_CONFIG_WR     0x09 /* RW */
> > > +#define REG_TEMP_DEC      0x10 /* RO */
> > > +#define REG_TEMP_HIGH_DEC 0x13 /* RW */
> > > +#define REG_TEMP_LOW_DEC  0x14 /* RW */
> > > +#define REG_ALERT_CONFIG  0xBF /* RW */
> > > +
> > > +#define STATUS_HIGH_ALERT BIT(4)
> > > +#define STATUS_LOW_ALERT  BIT(3)
> > > +#define CONFIG_ALERT_MASK BIT(7)
> > > +#define ALARM_EN          BIT(0)
> > > +
> > > +/* The temperature stored are in units of 0.125 degrees. */
> > > +#define TEMP_UNIT_IN_MILLIDEGREE 125
> > > +#define LIMIT_LOW (10500)
> > > +#define LIMIT_HIGH (55125)
> > > +
> > > +static uint32_t qmp_sbtsi_get_temperature(const char *id)
> > > +{
> > > +    QDict *response;
> > > +    int ret;
> > > +
> > > +    response = qmp("{ 'execute': 'qom-get', 'arguments': { 'path':
> %s, "
> > > +                   "'property': 'temperature' } }", id);
> > > +    g_assert(qdict_haskey(response, "return"));
> > > +    ret = (uint32_t)qdict_get_int(response, "return");
> > > +    qobject_unref(response);
> > > +    return ret;
> > > +}
> > > +
> > > +static void qmp_sbtsi_set_temperature(const char *id, uint32_t value)
> > > +{
> > > +    QDict *response;
> > > +
> > > +    response = qmp("{ 'execute': 'qom-set', 'arguments': { 'path':
> %s, "
> > > +                   "'property': 'temperature', 'value': %d } }", id,
> > > value);
> > > +    g_assert(qdict_haskey(response, "return"));
> > > +    qobject_unref(response);
> > > +}
> > > +
> > > +/*
> > > + * Compute the temperature using the integer and decimal part and
> return
> > > + * millidegrees. The decimal part are only the top 3 bits so we shift
> it
> > > by
> > > + * 5 here.
> > > + */
> > > +static uint32_t regs_to_temp(uint8_t integer, uint8_t decimal)
> > > +{
> > > +    return ((integer << 3) + (decimal >> 5)) *
> TEMP_UNIT_IN_MILLIDEGREE;
> > > +}
> > > +
> > > +/*
> > > + * Compute the integer and decimal parts of the temperature in
> > > millidegrees.
> > > + * H/W store the decimal in the top 3 bits so we shift it by 5.
> > > + */
> > > +static void temp_to_regs(uint32_t temp, uint8_t *integer, uint8_t
> > > *decimal)
> > > +{
> > > +    temp /= TEMP_UNIT_IN_MILLIDEGREE;
> > > +    *integer = temp >> 3;
> > > +    *decimal = (temp & 0x7) << 5;
> > > +}
> > > +
> > > +static void tx_rx(void *obj, void *data, QGuestAllocator *alloc)
> > > +{
> > > +    uint16_t value;
> > > +    uint8_t integer, decimal;
> > > +    QI2CDevice *i2cdev = (QI2CDevice *)obj;
> > > +
> > > +    /* Test default values */
> > > +    value = qmp_sbtsi_get_temperature(TEST_ID);
> > > +    g_assert_cmpuint(value, ==, 0);
> > > +
> > > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 0);
> > > +
> > > +    /* Test setting temperature */
> > > +    qmp_sbtsi_set_temperature(TEST_ID, 20000);
> > > +    value = qmp_sbtsi_get_temperature(TEST_ID);
> > > +    g_assert_cmpuint(value, ==, 20000);
> > > +
> > > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 20000);
> > > +
> > > +    /* Set alert mask in config */
> > > +    i2c_set8(i2cdev, REG_CONFIG_WR, CONFIG_ALERT_MASK);
> > > +    value = i2c_get8(i2cdev, REG_CONFIG);
> > > +    g_assert_cmphex(value, ==, CONFIG_ALERT_MASK);
> > > +    /* Enable alarm_en */
> > > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, ALARM_EN);
> > > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
> > > +    g_assert_cmphex(value, ==, ALARM_EN);
> > > +
> > > +    /* Test setting limits */
> > > +    /* Limit low = 10.500 */
> > > +    temp_to_regs(LIMIT_LOW, &integer, &decimal);
> > > +    i2c_set8(i2cdev, REG_TEMP_LOW_INT, integer);
> > > +    i2c_set8(i2cdev, REG_TEMP_LOW_DEC, decimal);
> > > +    integer = i2c_get8(i2cdev, REG_TEMP_LOW_INT);
> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_LOW_DEC);
> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, LIMIT_LOW);
> > > +    /* Limit high = 55.125 */
> > > +    temp_to_regs(LIMIT_HIGH, &integer, &decimal);
> > > +    i2c_set8(i2cdev, REG_TEMP_HIGH_INT, integer);
> > > +    i2c_set8(i2cdev, REG_TEMP_HIGH_DEC, decimal);
> > > +    integer = i2c_get8(i2cdev, REG_TEMP_HIGH_INT);
> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_HIGH_DEC);
> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, LIMIT_HIGH);
> > > +    /* No alert is generated. */
> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> > > +    g_assert_cmphex(value, ==, 0);
> > > +
> > > +    /* Test alert for low temperature */
> > > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_LOW);
> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> > > +    g_assert_cmphex(value, ==, STATUS_LOW_ALERT);
> > > +
> > > +    /* Test alert for high temperature */
> > > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_HIGH);
> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> > > +    g_assert_cmphex(value, ==, STATUS_HIGH_ALERT);
> > > +
> > > +    /* Disable alarm_en */
> > > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, 0);
> > > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
> > > +    g_assert_cmphex(value, ==, 0);
> > > +    /* No alert when alarm_en is false. */
> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> > > +    g_assert_cmphex(value, ==, 0);
> > > +}
> > > +
> > > +static void sbtsi_register_nodes(void)
> > > +{
> > > +    QOSGraphEdgeOptions opts = {
> > > +        .extra_device_opts = "id=" TEST_ID ",address=0x4c"
> > > +    };
> > > +    add_qi2c_address(&opts, &(QI2CAddress) { TEST_ADDR });
> > > +
> > > +    qos_node_create_driver("sbtsi", i2c_device_create);
> > > +    qos_node_consumes("sbtsi", "i2c-bus", &opts);
> > > +
> > > +    qos_add_test("tx-rx", "sbtsi", tx_rx, NULL);
> > > +}
> > > +libqos_init(sbtsi_register_nodes);
> > > --
> >
> >
> > + Corey for i2c maintainer.  The new sensor directory is mostly if not
> > entirely i2c devices.  I didn't create a maintainer entry for this i2c
> > device, but I can if desired and send out a v2.
>
> Yeah, I guess I should be maintainer there.  I'll queue up a change for
> that.  Thanks.
>
> -corey
>
> >
> >
> > > 2.34.1.575.g55b058a8bb-goog
> > >
> > >
>

Hao Wu Jan. 27, 2022, 12:09 a.m. UTC | #9

Hi,

Sorry for the late reply. I'm not sure what "auto-increment" means here.
The kernel driver at
https://lkml.org/lkml/2020/12/11/968
only has byte-size read/write operations, so I don't see a problem here.
The values are extracted
from the datasheet.

On Tue, Jan 18, 2022 at 9:10 AM Patrick Venture <[e-mail]> wrote:

>
>
> On Mon, Jan 17, 2022 at 6:05 AM Corey Minyard <[e-mail]> wrote:
>
>> On Sun, Jan 09, 2022 at 06:17:34PM -0800, Patrick Venture wrote:
>> > On Fri, Jan 7, 2022 at 7:04 PM Patrick Venture <[e-mail]>
>> wrote:
>> >
>> > > From: Hao Wu <[e-mail]>
>> > >
>> > > SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
>> > > interface that reports AMD SoC's Ttcl (normalized temperature),
>> > > and resembles a typical 8-pin remote temperature sensor's I2C
>> interface
>> > > to BMC.
>> > >
>> > > This patch implements a basic AMD SB-TSI sensor that is
>> > > compatible with the open-source data sheet from AMD and Linux
>> > > kernel driver.
>> > >
>> > > Reference:
>> > > Linux kernel driver:
>> > > https://lkml.org/lkml/2020/12/11/968
>> > > Register Map:
>> > > https://developer.amd.com/wp-content/resources/56255_3_03.PDF
>> > > (Chapter 6)
>> > >
>> > > Signed-off-by: Hao Wu <[e-mail]>
>> > > Reviewed-by: Doug Evans <[e-mail]>
>> > > ---
>> > >  hw/sensor/Kconfig            |   4 +
>> > >  hw/sensor/meson.build        |   1 +
>> > >  hw/sensor/tmp_sbtsi.c        | 393
>> +++++++++++++++++++++++++++++++++++
>> > >  hw/sensor/trace-events       |   5 +
>> > >  hw/sensor/trace.h            |   1 +
>> > >  meson.build                  |   1 +
>> > >  tests/qtest/meson.build      |   1 +
>> > >  tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++
>> > >  8 files changed, 586 insertions(+)
>> > >  create mode 100644 hw/sensor/tmp_sbtsi.c
>> > >  create mode 100644 hw/sensor/trace-events
>> > >  create mode 100644 hw/sensor/trace.h
>> > >  create mode 100644 tests/qtest/tmp_sbtsi-test.c
>> > >
>> > > diff --git a/hw/sensor/Kconfig b/hw/sensor/Kconfig
>> > > index 9c8a049b06..27f6f79c84 100644
>> > > --- a/hw/sensor/Kconfig
>> > > +++ b/hw/sensor/Kconfig
>> > > @@ -21,3 +21,7 @@ config ADM1272
>> > >  config MAX34451
>> > >      bool
>> > >      depends on I2C
>> > > +
>> > > +config AMDSBTSI
>> > > +    bool
>> > > +    depends on I2C
>> > > diff --git a/hw/sensor/meson.build b/hw/sensor/meson.build
>> > > index 059c4ca935..f7b0e645eb 100644
>> > > --- a/hw/sensor/meson.build
>> > > +++ b/hw/sensor/meson.build
>> > > @@ -4,3 +4,4 @@ softmmu_ss.add(when: 'CONFIG_DPS310', if_true:
>> > > files('dps310.c'))
>> > >  softmmu_ss.add(when: 'CONFIG_EMC141X', if_true: files('emc141x.c'))
>> > >  softmmu_ss.add(when: 'CONFIG_ADM1272', if_true: files('adm1272.c'))
>> > >  softmmu_ss.add(when: 'CONFIG_MAX34451', if_true: files('max34451.c'))
>> > > +softmmu_ss.add(when: 'CONFIG_AMDSBTSI', if_true:
>> files('tmp_sbtsi.c'))
>> > > diff --git a/hw/sensor/tmp_sbtsi.c b/hw/sensor/tmp_sbtsi.c
>> > > new file mode 100644
>> > > index 0000000000..b68c7ebf61
>> > > --- /dev/null
>> > > +++ b/hw/sensor/tmp_sbtsi.c
>> > > @@ -0,0 +1,393 @@
>> > > +/*
>> > > + * AMD SBI Temperature Sensor Interface (SB-TSI)
>> > > + *
>> > > + * Copyright 2021 Google LLC
>> > > + *
>> > > + * This program is free software; you can redistribute it and/or
>> modify it
>> > > + * under the terms of the GNU General Public License as published by
>> the
>> > > + * Free Software Foundation; either version 2 of the License, or
>> > > + * (at your option) any later version.
>> > > + *
>> > > + * This program is distributed in the hope that it will be useful,
>> but
>> > > WITHOUT
>> > > + * ANY WARRANTY; without even the implied warranty of
>> MERCHANTABILITY or
>> > > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
>> License
>> > > + * for more details.
>> > > + */
>> > > +
>> > > +#include "qemu/osdep.h"
>> > > +#include "hw/i2c/smbus_slave.h"
>> > > +#include "hw/irq.h"
>> > > +#include "migration/vmstate.h"
>> > > +#include "qapi/error.h"
>> > > +#include "qapi/visitor.h"
>> > > +#include "qemu/log.h"
>> > > +#include "qemu/module.h"
>> > > +#include "trace.h"
>> > > +
>> > > +#define TYPE_SBTSI "sbtsi"
>> > > +#define SBTSI(obj) OBJECT_CHECK(SBTSIState, (obj), TYPE_SBTSI)
>> > > +
>> > > +/**
>> > > + * SBTSIState:
>> > > + * temperatures are in units of 0.125 degrees
>> > > + * @temperature: Temperature
>> > > + * @limit_low: Lowest temperature
>> > > + * @limit_high: Highest temperature
>> > > + * @status: The status register
>> > > + * @config: The config register
>> > > + * @alert_config: The config for alarm_l output.
>> > > + * @addr: The address to read/write for the next cmd.
>> > > + * @alarm: The alarm_l output pin (GPIO)
>> > > + */
>> > > +typedef struct SBTSIState {
>> > > +    SMBusDevice parent;
>> > > +
>> > > +    uint32_t temperature;
>> > > +    uint32_t limit_low;
>> > > +    uint32_t limit_high;
>> > > +    uint8_t status;
>> > > +    uint8_t config;
>> > > +    uint8_t alert_config;
>> > > +    uint8_t addr;
>> > > +    qemu_irq alarm;
>> > > +} SBTSIState;
>> > > +
>> > > +/*
>> > > + * SB-TSI registers only support SMBus byte data access. "_INT"
>> registers
>> > > are
>> > > + * the integer part of a temperature value or limit, and "_DEC"
>> registers
>> > > are
>> > > + * corresponding decimal parts.
>> > > + */
>> > > +#define SBTSI_REG_TEMP_INT      0x01 /* RO */
>> > > +#define SBTSI_REG_STATUS        0x02 /* RO */
>> > > +#define SBTSI_REG_CONFIG        0x03 /* RO */
>> > > +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */
>> > > +#define SBTSI_REG_TEMP_LOW_INT  0x08 /* RW */
>> > > +#define SBTSI_REG_CONFIG_WR     0x09 /* RW */
>> > > +#define SBTSI_REG_TEMP_DEC      0x10 /* RO */
>> > > +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */
>> > > +#define SBTSI_REG_TEMP_LOW_DEC  0x14 /* RW */
>> > > +#define SBTSI_REG_ALERT_CONFIG  0xBF /* RW */
>> > > +#define SBTSI_REG_MAN           0xFE /* RO */
>> > > +#define SBTSI_REG_REV           0xFF /* RO */
>> > > +
>> > > +#define SBTSI_STATUS_HIGH_ALERT BIT(4)
>> > > +#define SBTSI_STATUS_LOW_ALERT  BIT(3)
>> > > +#define SBTSI_CONFIG_ALERT_MASK BIT(7)
>> > > +#define SBTSI_ALARM_EN          BIT(0)
>> > > +
>> > > +#define SBTSI_LIMIT_LOW_DEFAULT (0)
>> > > +#define SBTSI_LIMIT_HIGH_DEFAULT (560)
>> > > +#define SBTSI_MAN_DEFAULT (0)
>> > > +#define SBTSI_REV_DEFAULT (4)
>> > > +#define SBTSI_ALARM_L "alarm_l"
>> > > +
>> > > +/* The temperature we stored are in units of 0.125 degrees. */
>> > > +#define SBTSI_TEMP_UNIT_IN_MILLIDEGREE 125
>> > > +
>> > > +/*
>> > > + * The integer part and decimal of the temperature both 8 bits.
>> > > + * Only the top 3 bits of the decimal parts are used.
>> > > + * So the max temperature is (2^8-1) + (2^3-1)/8 = 255.875 degrees.
>> > > + */
>> > > +#define SBTSI_TEMP_MAX 255875
>> > > +
>> > > +/* The integer part of the temperature in terms of 0.125 degrees. */
>> > > +static uint8_t get_temp_int(uint32_t temp)
>> > > +{
>> > > +    return temp >> 3;
>> > > +}
>> > > +
>> > > +/*
>> > > + * The decimal part of the temperature, in terms of 0.125 degrees.
>> > > + * H/W store it in the top 3 bits so we shift it by 5.
>> > > + */
>> > > +static uint8_t get_temp_dec(uint32_t temp)
>> > > +{
>> > > +    return (temp & 0x7) << 5;
>> > > +}
>> > > +
>> > > +/*
>> > > + * Compute the temperature using the integer and decimal part,
>> > > + * in terms of 0.125 degrees. The decimal part are only the top 3
>> bits
>> > > + * so we shift it by 5 here.
>> > > + */
>> > > +static uint32_t compute_temp(uint8_t integer, uint8_t decimal)
>> > > +{
>> > > +    return (integer << 3) + (decimal >> 5);
>> > > +}
>> > > +
>> > > +/* Compute new temp with new int part of the temperature. */
>> > > +static uint32_t compute_temp_int(uint32_t temp, uint8_t integer)
>> > > +{
>> > > +    return compute_temp(integer, get_temp_dec(temp));
>> > > +}
>> > > +
>> > > +/* Compute new temp with new dec part of the temperature. */
>> > > +static uint32_t compute_temp_dec(uint32_t temp, uint8_t decimal)
>> > > +{
>> > > +    return compute_temp(get_temp_int(temp), decimal);
>> > > +}
>> > > +
>> > > +/* The integer part of the temperature. */
>> > > +static void sbtsi_update_status(SBTSIState *s)
>> > > +{
>> > > +    s->status = 0;
>> > > +    if (s->alert_config & SBTSI_ALARM_EN) {
>> > > +        if (s->temperature >= s->limit_high) {
>> > > +            s->status |= SBTSI_STATUS_HIGH_ALERT;
>> > > +        }
>> > > +        if (s->temperature <= s->limit_low) {
>> > > +            s->status |= SBTSI_STATUS_LOW_ALERT;
>> > > +        }
>> > > +    }
>> > > +}
>> > > +
>> > > +static void sbtsi_update_alarm(SBTSIState *s)
>> > > +{
>> > > +    sbtsi_update_status(s);
>> > > +    if (s->status != 0 && !(s->config & SBTSI_CONFIG_ALERT_MASK)) {
>> > > +        qemu_irq_raise(s->alarm);
>> > > +    } else {
>> > > +        qemu_irq_lower(s->alarm);
>> > > +    }
>> > > +}
>> > > +
>> > > +static uint8_t sbtsi_read_byte(SMBusDevice *d)
>> > > +{
>> > > +    SBTSIState *s = SBTSI(d);
>> > > +    uint8_t data = 0;
>> > > +
>> > > +    switch (s->addr) {
>> > > +    case SBTSI_REG_TEMP_INT:
>> > > +        data = get_temp_int(s->temperature);
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_TEMP_DEC:
>> > > +        data = get_temp_dec(s->temperature);
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_TEMP_HIGH_INT:
>> > > +        data = get_temp_int(s->limit_high);
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_TEMP_LOW_INT:
>> > > +        data = get_temp_int(s->limit_low);
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_TEMP_HIGH_DEC:
>> > > +        data = get_temp_dec(s->limit_high);
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_TEMP_LOW_DEC:
>> > > +        data = get_temp_dec(s->limit_low);
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_CONFIG:
>> > > +    case SBTSI_REG_CONFIG_WR:
>> > > +        data = s->config;
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_STATUS:
>> > > +        sbtsi_update_alarm(s);
>> > > +        data = s->status;
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_ALERT_CONFIG:
>> > > +        data = s->alert_config;
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_MAN:
>> > > +        data = SBTSI_MAN_DEFAULT;
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_REV:
>> > > +        data = SBTSI_REV_DEFAULT;
>> > > +        break;
>>
>> Does this device do some sort of auto-increment on the address when
>> reading/writing?
>>
>
> +Hao Wu <[e-mail]>   - Please take a look at the above
> question.  I imagine it's a while since you've thought about it, but please
> double check :)
> Thanks!
>
>
>> Other than that possible issue, I don't see anything else, it's pretty
>> straightforward.
>>
>> > > +
>> > > +    default:
>> > > +        qemu_log_mask(LOG_GUEST_ERROR,
>> > > +                "%s: reading from invalid reg: 0x%02x\n",
>> > > +                __func__, s->addr);
>> > > +        break;
>> > > +    }
>> > > +
>> > > +    trace_tmp_sbtsi_read_data(s->addr, data);
>> > > +    return data;
>> > > +}
>> > > +
>> > > +static void sbtsi_write(SBTSIState *s, uint8_t data)
>> > > +{
>> > > +    trace_tmp_sbtsi_write_data(s->addr, data);
>> > > +    switch (s->addr) {
>> > > +    case SBTSI_REG_CONFIG_WR:
>> > > +        s->config = data;
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_TEMP_HIGH_INT:
>> > > +        s->limit_high = compute_temp_int(s->limit_high, data);
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_TEMP_LOW_INT:
>> > > +        s->limit_low = compute_temp_int(s->limit_low, data);
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_TEMP_HIGH_DEC:
>> > > +        s->limit_high = compute_temp_dec(s->limit_high, data);
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_TEMP_LOW_DEC:
>> > > +        s->limit_low = compute_temp_dec(s->limit_low, data);
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_ALERT_CONFIG:
>> > > +        s->alert_config = data;
>> > > +        break;
>> > > +
>> > > +    case SBTSI_REG_TEMP_INT:
>> > > +    case SBTSI_REG_TEMP_DEC:
>> > > +    case SBTSI_REG_CONFIG:
>> > > +    case SBTSI_REG_STATUS:
>> > > +    case SBTSI_REG_MAN:
>> > > +    case SBTSI_REG_REV:
>> > > +        qemu_log_mask(LOG_GUEST_ERROR,
>> > > +                "%s: writing to read only reg: 0x%02x data:
>> 0x%02x\n",
>> > > +                __func__, s->addr, data);
>> > > +        break;
>> > > +
>> > > +    default:
>> > > +        qemu_log_mask(LOG_GUEST_ERROR,
>> > > +                "%s: writing to invalid reg: 0x%02x data: 0x%02x\n",
>> > > +                __func__, s->addr, data);
>> > > +        break;
>> > > +    }
>> > > +    sbtsi_update_alarm(s);
>> > > +}
>> > > +
>> > > +static int sbtsi_write_data(SMBusDevice *d, uint8_t *buf, uint8_t
>> len)
>> > > +{
>> > > +    SBTSIState *s = SBTSI(d);
>> > > +
>> > > +    if (len == 0) {
>> > > +        qemu_log_mask(LOG_GUEST_ERROR, "%s: writing empty data\n",
>> > > __func__);
>> > > +        return -1;
>> > > +    }
>> > > +
>> > > +    s->addr = buf[0];
>> > > +    if (len > 1) {
>> > > +        sbtsi_write(s, buf[1]);
>> > > +        if (len > 2) {
>> > > +            qemu_log_mask(LOG_GUEST_ERROR, "%s: extra data at end\n",
>> > > __func__);
>> > > +        }
>> > > +    }
>> > > +    return 0;
>> > > +}
>> > > +
>> > > +/* Units are millidegrees. */
>> > > +static void sbtsi_get_temperature(Object *obj, Visitor *v, const char
>> > > *name,
>> > > +                                  void *opaque, Error **errp)
>> > > +{
>> > > +    SBTSIState *s = SBTSI(obj);
>> > > +    uint32_t temp = s->temperature * SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
>> > > +
>> > > +    visit_type_uint32(v, name, &temp, errp);
>> > > +}
>> > > +
>> > > +/* Units are millidegrees. */
>> > > +static void sbtsi_set_temperature(Object *obj, Visitor *v, const char
>> > > *name,
>> > > +                                  void *opaque, Error **errp)
>> > > +{
>> > > +    SBTSIState *s = SBTSI(obj);
>> > > +    uint32_t temp;
>> > > +
>> > > +    if (!visit_type_uint32(v, name, &temp, errp)) {
>> > > +        return;
>> > > +    }
>> > > +    if (temp > SBTSI_TEMP_MAX) {
>> > > +        error_setg(errp, "value %" PRIu32 ".%03" PRIu32 " C is out of
>> > > range",
>> > > +                   temp / 1000, temp % 1000);
>> > > +        return;
>> > > +    }
>> > > +
>> > > +    s->temperature = temp / SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
>> > > +    sbtsi_update_alarm(s);
>> > > +}
>> > > +
>> > > +static int sbtsi_post_load(void *opaque, int version_id)
>> > > +{
>> > > +    SBTSIState *s = opaque;
>> > > +
>> > > +    sbtsi_update_alarm(s);
>> > > +    return 0;
>> > > +}
>> > > +
>> > > +static const VMStateDescription vmstate_sbtsi = {
>> > > +    .name = "SBTSI",
>> > > +    .version_id = 0,
>> > > +    .minimum_version_id = 0,
>> > > +    .post_load = sbtsi_post_load,
>> > > +    .fields = (VMStateField[]) {
>> > > +        VMSTATE_UINT32(temperature, SBTSIState),
>> > > +        VMSTATE_UINT32(limit_low, SBTSIState),
>> > > +        VMSTATE_UINT32(limit_high, SBTSIState),
>> > > +        VMSTATE_UINT8(config, SBTSIState),
>> > > +        VMSTATE_UINT8(status, SBTSIState),
>> > > +        VMSTATE_UINT8(addr, SBTSIState),
>> > > +        VMSTATE_END_OF_LIST()
>> > > +    }
>> > > +};
>> > > +
>> > > +static void sbtsi_enter_reset(Object *obj, ResetType type)
>> > > +{
>> > > +    SBTSIState *s = SBTSI(obj);
>> > > +
>> > > +    s->config = 0;
>> > > +    s->limit_low = SBTSI_LIMIT_LOW_DEFAULT;
>> > > +    s->limit_high = SBTSI_LIMIT_HIGH_DEFAULT;
>> > > +}
>> > > +
>> > > +static void sbtsi_hold_reset(Object *obj)
>> > > +{
>> > > +    SBTSIState *s = SBTSI(obj);
>> > > +
>> > > +    qemu_irq_lower(s->alarm);
>> > > +}
>> > > +
>> > > +static void sbtsi_init(Object *obj)
>> > > +{
>> > > +    SBTSIState *s = SBTSI(obj);
>> > > +
>> > > +    /* Current temperature in millidegrees. */
>> > > +    object_property_add(obj, "temperature", "uint32",
>> > > +                        sbtsi_get_temperature, sbtsi_set_temperature,
>> > > +                        NULL, NULL);
>> > > +    qdev_init_gpio_out_named(DEVICE(obj), &s->alarm, SBTSI_ALARM_L,
>> 0);
>> > > +}
>> > > +
>> > > +static void sbtsi_class_init(ObjectClass *klass, void *data)
>> > > +{
>> > > +    ResettableClass *rc = RESETTABLE_CLASS(klass);
>> > > +    DeviceClass *dc = DEVICE_CLASS(klass);
>> > > +    SMBusDeviceClass *k = SMBUS_DEVICE_CLASS(klass);
>> > > +
>> > > +    dc->desc = "SB-TSI Temperature Sensor";
>> > > +    dc->vmsd = &vmstate_sbtsi;
>> > > +    k->write_data = sbtsi_write_data;
>> > > +    k->receive_byte = sbtsi_read_byte;
>> > > +    rc->phases.enter = sbtsi_enter_reset;
>> > > +    rc->phases.hold = sbtsi_hold_reset;
>> > > +}
>> > > +
>> > > +static const TypeInfo sbtsi_info = {
>> > > +    .name          = TYPE_SBTSI,
>> > > +    .parent        = TYPE_SMBUS_DEVICE,
>> > > +    .instance_size = sizeof(SBTSIState),
>> > > +    .instance_init = sbtsi_init,
>> > > +    .class_init    = sbtsi_class_init,
>> > > +};
>> > > +
>> > > +static void sbtsi_register_types(void)
>> > > +{
>> > > +    type_register_static(&sbtsi_info);
>> > > +}
>> > > +
>> > > +type_init(sbtsi_register_types)
>> > > diff --git a/hw/sensor/trace-events b/hw/sensor/trace-events
>> > > new file mode 100644
>> > > index 0000000000..21ab3809e2
>> > > --- /dev/null
>> > > +++ b/hw/sensor/trace-events
>> > > @@ -0,0 +1,5 @@
>> > > +# See docs/devel/tracing.rst for syntax documentation.
>> > > +
>> > > +# tmp_sbtsi.c
>> > > +tmp_sbtsi_write_data(uint8_t addr, uint8_t value) "SBTSI write
>> > > addr:0x%02x data: 0x%02x"
>> > > +tmp_sbtsi_read_data(uint8_t addr, uint8_t value) "SBTSI read
>> addr:0x%02x
>> > > data: 0x%02x"
>> > > diff --git a/hw/sensor/trace.h b/hw/sensor/trace.h
>> > > new file mode 100644
>> > > index 0000000000..e4721560b0
>> > > --- /dev/null
>> > > +++ b/hw/sensor/trace.h
>> > > @@ -0,0 +1 @@
>> > > +#include "trace/trace-hw_sensor.h"
>> > > diff --git a/meson.build b/meson.build
>> > > index 53065e96ec..f8ab0bf74e 100644
>> > > --- a/meson.build
>> > > +++ b/meson.build
>> > > @@ -2494,6 +2494,7 @@ if have_system
>> > >      'hw/rtc',
>> > >      'hw/s390x',
>> > >      'hw/scsi',
>> > > +    'hw/sensor',
>> > >      'hw/sd',
>> > >      'hw/sh4',
>> > >      'hw/sparc',
>> > > diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
>> > > index 37e1eaa449..d1a8c38f74 100644
>> > > --- a/tests/qtest/meson.build
>> > > +++ b/tests/qtest/meson.build
>> > > @@ -254,6 +254,7 @@ qos_test_ss.add(
>> > >    'spapr-phb-test.c',
>> > >    'tmp105-test.c',
>> > >    'emc141x-test.c',
>> > > +  'tmp_sbtsi-test.c',
>> > >    'usb-hcd-ohci-test.c',
>> > >    'virtio-test.c',
>> > >    'virtio-blk-test.c',
>> > > diff --git a/tests/qtest/tmp_sbtsi-test.c
>> b/tests/qtest/tmp_sbtsi-test.c
>> > > new file mode 100644
>> > > index 0000000000..7f5fafacc7
>> > > --- /dev/null
>> > > +++ b/tests/qtest/tmp_sbtsi-test.c
>> > > @@ -0,0 +1,180 @@
>> > > +/*
>> > > + * QTests for the SBTSI temperature sensor
>> > > + *
>> > > + * Copyright 2020 Google LLC
>> > > + *
>> > > + * This program is free software; you can redistribute it and/or
>> modify it
>> > > + * under the terms of the GNU General Public License as published by
>> the
>> > > + * Free Software Foundation; either version 2 of the License, or
>> > > + * (at your option) any later version.
>> > > + *
>> > > + * This program is distributed in the hope that it will be useful,
>> but
>> > > WITHOUT
>> > > + * ANY WARRANTY; without even the implied warranty of
>> MERCHANTABILITY or
>> > > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
>> License
>> > > + * for more details.
>> > > + */
>> > > +
>> > > +#include "qemu/osdep.h"
>> > > +
>> > > +#include "libqtest-single.h"
>> > > +#include "libqos/qgraph.h"
>> > > +#include "libqos/i2c.h"
>> > > +#include "qapi/qmp/qdict.h"
>> > > +#include "qemu/bitops.h"
>> > > +
>> > > +#define TEST_ID   "sbtsi-test"
>> > > +#define TEST_ADDR (0x4c)
>> > > +
>> > > +/*
>> > > + * SB-TSI registers only support SMBus byte data access. "_INT"
>> registers
>> > > are
>> > > + * the integer part of a temperature value or limit, and "_DEC"
>> registers
>> > > are
>> > > + * corresponding decimal parts.
>> > > + */
>> > > +#define REG_TEMP_INT      0x01 /* RO */
>> > > +#define REG_STATUS        0x02 /* RO */
>> > > +#define REG_CONFIG        0x03 /* RO */
>> > > +#define REG_TEMP_HIGH_INT 0x07 /* RW */
>> > > +#define REG_TEMP_LOW_INT  0x08 /* RW */
>> > > +#define REG_CONFIG_WR     0x09 /* RW */
>> > > +#define REG_TEMP_DEC      0x10 /* RO */
>> > > +#define REG_TEMP_HIGH_DEC 0x13 /* RW */
>> > > +#define REG_TEMP_LOW_DEC  0x14 /* RW */
>> > > +#define REG_ALERT_CONFIG  0xBF /* RW */
>> > > +
>> > > +#define STATUS_HIGH_ALERT BIT(4)
>> > > +#define STATUS_LOW_ALERT  BIT(3)
>> > > +#define CONFIG_ALERT_MASK BIT(7)
>> > > +#define ALARM_EN          BIT(0)
>> > > +
>> > > +/* The temperature stored are in units of 0.125 degrees. */
>> > > +#define TEMP_UNIT_IN_MILLIDEGREE 125
>> > > +#define LIMIT_LOW (10500)
>> > > +#define LIMIT_HIGH (55125)
>> > > +
>> > > +static uint32_t qmp_sbtsi_get_temperature(const char *id)
>> > > +{
>> > > +    QDict *response;
>> > > +    int ret;
>> > > +
>> > > +    response = qmp("{ 'execute': 'qom-get', 'arguments': { 'path':
>> %s, "
>> > > +                   "'property': 'temperature' } }", id);
>> > > +    g_assert(qdict_haskey(response, "return"));
>> > > +    ret = (uint32_t)qdict_get_int(response, "return");
>> > > +    qobject_unref(response);
>> > > +    return ret;
>> > > +}
>> > > +
>> > > +static void qmp_sbtsi_set_temperature(const char *id, uint32_t value)
>> > > +{
>> > > +    QDict *response;
>> > > +
>> > > +    response = qmp("{ 'execute': 'qom-set', 'arguments': { 'path':
>> %s, "
>> > > +                   "'property': 'temperature', 'value': %d } }", id,
>> > > value);
>> > > +    g_assert(qdict_haskey(response, "return"));
>> > > +    qobject_unref(response);
>> > > +}
>> > > +
>> > > +/*
>> > > + * Compute the temperature using the integer and decimal part and
>> return
>> > > + * millidegrees. The decimal part are only the top 3 bits so we
>> shift it
>> > > by
>> > > + * 5 here.
>> > > + */
>> > > +static uint32_t regs_to_temp(uint8_t integer, uint8_t decimal)
>> > > +{
>> > > +    return ((integer << 3) + (decimal >> 5)) *
>> TEMP_UNIT_IN_MILLIDEGREE;
>> > > +}
>> > > +
>> > > +/*
>> > > + * Compute the integer and decimal parts of the temperature in
>> > > millidegrees.
>> > > + * H/W store the decimal in the top 3 bits so we shift it by 5.
>> > > + */
>> > > +static void temp_to_regs(uint32_t temp, uint8_t *integer, uint8_t
>> > > *decimal)
>> > > +{
>> > > +    temp /= TEMP_UNIT_IN_MILLIDEGREE;
>> > > +    *integer = temp >> 3;
>> > > +    *decimal = (temp & 0x7) << 5;
>> > > +}
>> > > +
>> > > +static void tx_rx(void *obj, void *data, QGuestAllocator *alloc)
>> > > +{
>> > > +    uint16_t value;
>> > > +    uint8_t integer, decimal;
>> > > +    QI2CDevice *i2cdev = (QI2CDevice *)obj;
>> > > +
>> > > +    /* Test default values */
>> > > +    value = qmp_sbtsi_get_temperature(TEST_ID);
>> > > +    g_assert_cmpuint(value, ==, 0);
>> > > +
>> > > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
>> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
>> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 0);
>> > > +
>> > > +    /* Test setting temperature */
>> > > +    qmp_sbtsi_set_temperature(TEST_ID, 20000);
>> > > +    value = qmp_sbtsi_get_temperature(TEST_ID);
>> > > +    g_assert_cmpuint(value, ==, 20000);
>> > > +
>> > > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
>> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
>> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 20000);
>> > > +
>> > > +    /* Set alert mask in config */
>> > > +    i2c_set8(i2cdev, REG_CONFIG_WR, CONFIG_ALERT_MASK);
>> > > +    value = i2c_get8(i2cdev, REG_CONFIG);
>> > > +    g_assert_cmphex(value, ==, CONFIG_ALERT_MASK);
>> > > +    /* Enable alarm_en */
>> > > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, ALARM_EN);
>> > > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
>> > > +    g_assert_cmphex(value, ==, ALARM_EN);
>> > > +
>> > > +    /* Test setting limits */
>> > > +    /* Limit low = 10.500 */
>> > > +    temp_to_regs(LIMIT_LOW, &integer, &decimal);
>> > > +    i2c_set8(i2cdev, REG_TEMP_LOW_INT, integer);
>> > > +    i2c_set8(i2cdev, REG_TEMP_LOW_DEC, decimal);
>> > > +    integer = i2c_get8(i2cdev, REG_TEMP_LOW_INT);
>> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_LOW_DEC);
>> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, LIMIT_LOW);
>> > > +    /* Limit high = 55.125 */
>> > > +    temp_to_regs(LIMIT_HIGH, &integer, &decimal);
>> > > +    i2c_set8(i2cdev, REG_TEMP_HIGH_INT, integer);
>> > > +    i2c_set8(i2cdev, REG_TEMP_HIGH_DEC, decimal);
>> > > +    integer = i2c_get8(i2cdev, REG_TEMP_HIGH_INT);
>> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_HIGH_DEC);
>> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, LIMIT_HIGH);
>> > > +    /* No alert is generated. */
>> > > +    value = i2c_get8(i2cdev, REG_STATUS);
>> > > +    g_assert_cmphex(value, ==, 0);
>> > > +
>> > > +    /* Test alert for low temperature */
>> > > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_LOW);
>> > > +    value = i2c_get8(i2cdev, REG_STATUS);
>> > > +    g_assert_cmphex(value, ==, STATUS_LOW_ALERT);
>> > > +
>> > > +    /* Test alert for high temperature */
>> > > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_HIGH);
>> > > +    value = i2c_get8(i2cdev, REG_STATUS);
>> > > +    g_assert_cmphex(value, ==, STATUS_HIGH_ALERT);
>> > > +
>> > > +    /* Disable alarm_en */
>> > > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, 0);
>> > > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
>> > > +    g_assert_cmphex(value, ==, 0);
>> > > +    /* No alert when alarm_en is false. */
>> > > +    value = i2c_get8(i2cdev, REG_STATUS);
>> > > +    g_assert_cmphex(value, ==, 0);
>> > > +}
>> > > +
>> > > +static void sbtsi_register_nodes(void)
>> > > +{
>> > > +    QOSGraphEdgeOptions opts = {
>> > > +        .extra_device_opts = "id=" TEST_ID ",address=0x4c"
>> > > +    };
>> > > +    add_qi2c_address(&opts, &(QI2CAddress) { TEST_ADDR });
>> > > +
>> > > +    qos_node_create_driver("sbtsi", i2c_device_create);
>> > > +    qos_node_consumes("sbtsi", "i2c-bus", &opts);
>> > > +
>> > > +    qos_add_test("tx-rx", "sbtsi", tx_rx, NULL);
>> > > +}
>> > > +libqos_init(sbtsi_register_nodes);
>> > > --
>> >
>> >
>> > + Corey for i2c maintainer.  The new sensor directory is mostly if not
>> > entirely i2c devices.  I didn't create a maintainer entry for this i2c
>> > device, but I can if desired and send out a v2.
>>
>> Yeah, I guess I should be maintainer there.  I'll queue up a change for
>> that.  Thanks.
>>
>> -corey
>>
>> >
>> >
>> > > 2.34.1.575.g55b058a8bb-goog
>> > >
>> > >
>>
>

Corey Minyard Jan. 27, 2022, 2:55 p.m. UTC | #10

On Wed, Jan 26, 2022 at 04:09:03PM -0800, Hao Wu wrote:
> Hi,
> 
> Sorry for the late reply. I'm not sure what "auto-increment" means here.

The question is: When a value is read, does the address automatically
increment.  I2C devices very often do this.  If you do a multi-byte
read, they often will read the value from address 0, then from address
1, etc.  Same for writes.

> The kernel driver at
> https://lkml.org/lkml/2020/12/11/968
> only has byte-size read/write operations, so I don't see a problem here.
> The values are extracted
> from the datasheet.

The *Linux* kernel driver my only do byte-size operations, but other
kernels may work different, and the Linux kernel may change.  You have
to implement from the datasheet, not the device driver.

Thanks,

-corey

> 
> On Tue, Jan 18, 2022 at 9:10 AM Patrick Venture <[e-mail]> wrote:
> 
> >
> >
> > On Mon, Jan 17, 2022 at 6:05 AM Corey Minyard <[e-mail]> wrote:
> >
> >> On Sun, Jan 09, 2022 at 06:17:34PM -0800, Patrick Venture wrote:
> >> > On Fri, Jan 7, 2022 at 7:04 PM Patrick Venture <[e-mail]>
> >> wrote:
> >> >
> >> > > From: Hao Wu <[e-mail]>
> >> > >
> >> > > SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
> >> > > interface that reports AMD SoC's Ttcl (normalized temperature),
> >> > > and resembles a typical 8-pin remote temperature sensor's I2C
> >> interface
> >> > > to BMC.
> >> > >
> >> > > This patch implements a basic AMD SB-TSI sensor that is
> >> > > compatible with the open-source data sheet from AMD and Linux
> >> > > kernel driver.
> >> > >
> >> > > Reference:
> >> > > Linux kernel driver:
> >> > > https://lkml.org/lkml/2020/12/11/968
> >> > > Register Map:
> >> > > https://developer.amd.com/wp-content/resources/56255_3_03.PDF
> >> > > (Chapter 6)
> >> > >
> >> > > Signed-off-by: Hao Wu <[e-mail]>
> >> > > Reviewed-by: Doug Evans <[e-mail]>
> >> > > ---
> >> > >  hw/sensor/Kconfig            |   4 +
> >> > >  hw/sensor/meson.build        |   1 +
> >> > >  hw/sensor/tmp_sbtsi.c        | 393
> >> +++++++++++++++++++++++++++++++++++
> >> > >  hw/sensor/trace-events       |   5 +
> >> > >  hw/sensor/trace.h            |   1 +
> >> > >  meson.build                  |   1 +
> >> > >  tests/qtest/meson.build      |   1 +
> >> > >  tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++
> >> > >  8 files changed, 586 insertions(+)
> >> > >  create mode 100644 hw/sensor/tmp_sbtsi.c
> >> > >  create mode 100644 hw/sensor/trace-events
> >> > >  create mode 100644 hw/sensor/trace.h
> >> > >  create mode 100644 tests/qtest/tmp_sbtsi-test.c
> >> > >
> >> > > diff --git a/hw/sensor/Kconfig b/hw/sensor/Kconfig
> >> > > index 9c8a049b06..27f6f79c84 100644
> >> > > --- a/hw/sensor/Kconfig
> >> > > +++ b/hw/sensor/Kconfig
> >> > > @@ -21,3 +21,7 @@ config ADM1272
> >> > >  config MAX34451
> >> > >      bool
> >> > >      depends on I2C
> >> > > +
> >> > > +config AMDSBTSI
> >> > > +    bool
> >> > > +    depends on I2C
> >> > > diff --git a/hw/sensor/meson.build b/hw/sensor/meson.build
> >> > > index 059c4ca935..f7b0e645eb 100644
> >> > > --- a/hw/sensor/meson.build
> >> > > +++ b/hw/sensor/meson.build
> >> > > @@ -4,3 +4,4 @@ softmmu_ss.add(when: 'CONFIG_DPS310', if_true:
> >> > > files('dps310.c'))
> >> > >  softmmu_ss.add(when: 'CONFIG_EMC141X', if_true: files('emc141x.c'))
> >> > >  softmmu_ss.add(when: 'CONFIG_ADM1272', if_true: files('adm1272.c'))
> >> > >  softmmu_ss.add(when: 'CONFIG_MAX34451', if_true: files('max34451.c'))
> >> > > +softmmu_ss.add(when: 'CONFIG_AMDSBTSI', if_true:
> >> files('tmp_sbtsi.c'))
> >> > > diff --git a/hw/sensor/tmp_sbtsi.c b/hw/sensor/tmp_sbtsi.c
> >> > > new file mode 100644
> >> > > index 0000000000..b68c7ebf61
> >> > > --- /dev/null
> >> > > +++ b/hw/sensor/tmp_sbtsi.c
> >> > > @@ -0,0 +1,393 @@
> >> > > +/*
> >> > > + * AMD SBI Temperature Sensor Interface (SB-TSI)
> >> > > + *
> >> > > + * Copyright 2021 Google LLC
> >> > > + *
> >> > > + * This program is free software; you can redistribute it and/or
> >> modify it
> >> > > + * under the terms of the GNU General Public License as published by
> >> the
> >> > > + * Free Software Foundation; either version 2 of the License, or
> >> > > + * (at your option) any later version.
> >> > > + *
> >> > > + * This program is distributed in the hope that it will be useful,
> >> but
> >> > > WITHOUT
> >> > > + * ANY WARRANTY; without even the implied warranty of
> >> MERCHANTABILITY or
> >> > > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
> >> License
> >> > > + * for more details.
> >> > > + */
> >> > > +
> >> > > +#include "qemu/osdep.h"
> >> > > +#include "hw/i2c/smbus_slave.h"
> >> > > +#include "hw/irq.h"
> >> > > +#include "migration/vmstate.h"
> >> > > +#include "qapi/error.h"
> >> > > +#include "qapi/visitor.h"
> >> > > +#include "qemu/log.h"
> >> > > +#include "qemu/module.h"
> >> > > +#include "trace.h"
> >> > > +
> >> > > +#define TYPE_SBTSI "sbtsi"
> >> > > +#define SBTSI(obj) OBJECT_CHECK(SBTSIState, (obj), TYPE_SBTSI)
> >> > > +
> >> > > +/**
> >> > > + * SBTSIState:
> >> > > + * temperatures are in units of 0.125 degrees
> >> > > + * @temperature: Temperature
> >> > > + * @limit_low: Lowest temperature
> >> > > + * @limit_high: Highest temperature
> >> > > + * @status: The status register
> >> > > + * @config: The config register
> >> > > + * @alert_config: The config for alarm_l output.
> >> > > + * @addr: The address to read/write for the next cmd.
> >> > > + * @alarm: The alarm_l output pin (GPIO)
> >> > > + */
> >> > > +typedef struct SBTSIState {
> >> > > +    SMBusDevice parent;
> >> > > +
> >> > > +    uint32_t temperature;
> >> > > +    uint32_t limit_low;
> >> > > +    uint32_t limit_high;
> >> > > +    uint8_t status;
> >> > > +    uint8_t config;
> >> > > +    uint8_t alert_config;
> >> > > +    uint8_t addr;
> >> > > +    qemu_irq alarm;
> >> > > +} SBTSIState;
> >> > > +
> >> > > +/*
> >> > > + * SB-TSI registers only support SMBus byte data access. "_INT"
> >> registers
> >> > > are
> >> > > + * the integer part of a temperature value or limit, and "_DEC"
> >> registers
> >> > > are
> >> > > + * corresponding decimal parts.
> >> > > + */
> >> > > +#define SBTSI_REG_TEMP_INT      0x01 /* RO */
> >> > > +#define SBTSI_REG_STATUS        0x02 /* RO */
> >> > > +#define SBTSI_REG_CONFIG        0x03 /* RO */
> >> > > +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */
> >> > > +#define SBTSI_REG_TEMP_LOW_INT  0x08 /* RW */
> >> > > +#define SBTSI_REG_CONFIG_WR     0x09 /* RW */
> >> > > +#define SBTSI_REG_TEMP_DEC      0x10 /* RO */
> >> > > +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */
> >> > > +#define SBTSI_REG_TEMP_LOW_DEC  0x14 /* RW */
> >> > > +#define SBTSI_REG_ALERT_CONFIG  0xBF /* RW */
> >> > > +#define SBTSI_REG_MAN           0xFE /* RO */
> >> > > +#define SBTSI_REG_REV           0xFF /* RO */
> >> > > +
> >> > > +#define SBTSI_STATUS_HIGH_ALERT BIT(4)
> >> > > +#define SBTSI_STATUS_LOW_ALERT  BIT(3)
> >> > > +#define SBTSI_CONFIG_ALERT_MASK BIT(7)
> >> > > +#define SBTSI_ALARM_EN          BIT(0)
> >> > > +
> >> > > +#define SBTSI_LIMIT_LOW_DEFAULT (0)
> >> > > +#define SBTSI_LIMIT_HIGH_DEFAULT (560)
> >> > > +#define SBTSI_MAN_DEFAULT (0)
> >> > > +#define SBTSI_REV_DEFAULT (4)
> >> > > +#define SBTSI_ALARM_L "alarm_l"
> >> > > +
> >> > > +/* The temperature we stored are in units of 0.125 degrees. */
> >> > > +#define SBTSI_TEMP_UNIT_IN_MILLIDEGREE 125
> >> > > +
> >> > > +/*
> >> > > + * The integer part and decimal of the temperature both 8 bits.
> >> > > + * Only the top 3 bits of the decimal parts are used.
> >> > > + * So the max temperature is (2^8-1) + (2^3-1)/8 = 255.875 degrees.
> >> > > + */
> >> > > +#define SBTSI_TEMP_MAX 255875
> >> > > +
> >> > > +/* The integer part of the temperature in terms of 0.125 degrees. */
> >> > > +static uint8_t get_temp_int(uint32_t temp)
> >> > > +{
> >> > > +    return temp >> 3;
> >> > > +}
> >> > > +
> >> > > +/*
> >> > > + * The decimal part of the temperature, in terms of 0.125 degrees.
> >> > > + * H/W store it in the top 3 bits so we shift it by 5.
> >> > > + */
> >> > > +static uint8_t get_temp_dec(uint32_t temp)
> >> > > +{
> >> > > +    return (temp & 0x7) << 5;
> >> > > +}
> >> > > +
> >> > > +/*
> >> > > + * Compute the temperature using the integer and decimal part,
> >> > > + * in terms of 0.125 degrees. The decimal part are only the top 3
> >> bits
> >> > > + * so we shift it by 5 here.
> >> > > + */
> >> > > +static uint32_t compute_temp(uint8_t integer, uint8_t decimal)
> >> > > +{
> >> > > +    return (integer << 3) + (decimal >> 5);
> >> > > +}
> >> > > +
> >> > > +/* Compute new temp with new int part of the temperature. */
> >> > > +static uint32_t compute_temp_int(uint32_t temp, uint8_t integer)
> >> > > +{
> >> > > +    return compute_temp(integer, get_temp_dec(temp));
> >> > > +}
> >> > > +
> >> > > +/* Compute new temp with new dec part of the temperature. */
> >> > > +static uint32_t compute_temp_dec(uint32_t temp, uint8_t decimal)
> >> > > +{
> >> > > +    return compute_temp(get_temp_int(temp), decimal);
> >> > > +}
> >> > > +
> >> > > +/* The integer part of the temperature. */
> >> > > +static void sbtsi_update_status(SBTSIState *s)
> >> > > +{
> >> > > +    s->status = 0;
> >> > > +    if (s->alert_config & SBTSI_ALARM_EN) {
> >> > > +        if (s->temperature >= s->limit_high) {
> >> > > +            s->status |= SBTSI_STATUS_HIGH_ALERT;
> >> > > +        }
> >> > > +        if (s->temperature <= s->limit_low) {
> >> > > +            s->status |= SBTSI_STATUS_LOW_ALERT;
> >> > > +        }
> >> > > +    }
> >> > > +}
> >> > > +
> >> > > +static void sbtsi_update_alarm(SBTSIState *s)
> >> > > +{
> >> > > +    sbtsi_update_status(s);
> >> > > +    if (s->status != 0 && !(s->config & SBTSI_CONFIG_ALERT_MASK)) {
> >> > > +        qemu_irq_raise(s->alarm);
> >> > > +    } else {
> >> > > +        qemu_irq_lower(s->alarm);
> >> > > +    }
> >> > > +}
> >> > > +
> >> > > +static uint8_t sbtsi_read_byte(SMBusDevice *d)
> >> > > +{
> >> > > +    SBTSIState *s = SBTSI(d);
> >> > > +    uint8_t data = 0;
> >> > > +
> >> > > +    switch (s->addr) {
> >> > > +    case SBTSI_REG_TEMP_INT:
> >> > > +        data = get_temp_int(s->temperature);
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_TEMP_DEC:
> >> > > +        data = get_temp_dec(s->temperature);
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_TEMP_HIGH_INT:
> >> > > +        data = get_temp_int(s->limit_high);
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_TEMP_LOW_INT:
> >> > > +        data = get_temp_int(s->limit_low);
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_TEMP_HIGH_DEC:
> >> > > +        data = get_temp_dec(s->limit_high);
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_TEMP_LOW_DEC:
> >> > > +        data = get_temp_dec(s->limit_low);
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_CONFIG:
> >> > > +    case SBTSI_REG_CONFIG_WR:
> >> > > +        data = s->config;
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_STATUS:
> >> > > +        sbtsi_update_alarm(s);
> >> > > +        data = s->status;
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_ALERT_CONFIG:
> >> > > +        data = s->alert_config;
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_MAN:
> >> > > +        data = SBTSI_MAN_DEFAULT;
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_REV:
> >> > > +        data = SBTSI_REV_DEFAULT;
> >> > > +        break;
> >>
> >> Does this device do some sort of auto-increment on the address when
> >> reading/writing?
> >>
> >
> > +Hao Wu <[e-mail]>   - Please take a look at the above
> > question.  I imagine it's a while since you've thought about it, but please
> > double check :)
> > Thanks!
> >
> >
> >> Other than that possible issue, I don't see anything else, it's pretty
> >> straightforward.
> >>
> >> > > +
> >> > > +    default:
> >> > > +        qemu_log_mask(LOG_GUEST_ERROR,
> >> > > +                "%s: reading from invalid reg: 0x%02x\n",
> >> > > +                __func__, s->addr);
> >> > > +        break;
> >> > > +    }
> >> > > +
> >> > > +    trace_tmp_sbtsi_read_data(s->addr, data);
> >> > > +    return data;
> >> > > +}
> >> > > +
> >> > > +static void sbtsi_write(SBTSIState *s, uint8_t data)
> >> > > +{
> >> > > +    trace_tmp_sbtsi_write_data(s->addr, data);
> >> > > +    switch (s->addr) {
> >> > > +    case SBTSI_REG_CONFIG_WR:
> >> > > +        s->config = data;
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_TEMP_HIGH_INT:
> >> > > +        s->limit_high = compute_temp_int(s->limit_high, data);
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_TEMP_LOW_INT:
> >> > > +        s->limit_low = compute_temp_int(s->limit_low, data);
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_TEMP_HIGH_DEC:
> >> > > +        s->limit_high = compute_temp_dec(s->limit_high, data);
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_TEMP_LOW_DEC:
> >> > > +        s->limit_low = compute_temp_dec(s->limit_low, data);
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_ALERT_CONFIG:
> >> > > +        s->alert_config = data;
> >> > > +        break;
> >> > > +
> >> > > +    case SBTSI_REG_TEMP_INT:
> >> > > +    case SBTSI_REG_TEMP_DEC:
> >> > > +    case SBTSI_REG_CONFIG:
> >> > > +    case SBTSI_REG_STATUS:
> >> > > +    case SBTSI_REG_MAN:
> >> > > +    case SBTSI_REG_REV:
> >> > > +        qemu_log_mask(LOG_GUEST_ERROR,
> >> > > +                "%s: writing to read only reg: 0x%02x data:
> >> 0x%02x\n",
> >> > > +                __func__, s->addr, data);
> >> > > +        break;
> >> > > +
> >> > > +    default:
> >> > > +        qemu_log_mask(LOG_GUEST_ERROR,
> >> > > +                "%s: writing to invalid reg: 0x%02x data: 0x%02x\n",
> >> > > +                __func__, s->addr, data);
> >> > > +        break;
> >> > > +    }
> >> > > +    sbtsi_update_alarm(s);
> >> > > +}
> >> > > +
> >> > > +static int sbtsi_write_data(SMBusDevice *d, uint8_t *buf, uint8_t
> >> len)
> >> > > +{
> >> > > +    SBTSIState *s = SBTSI(d);
> >> > > +
> >> > > +    if (len == 0) {
> >> > > +        qemu_log_mask(LOG_GUEST_ERROR, "%s: writing empty data\n",
> >> > > __func__);
> >> > > +        return -1;
> >> > > +    }
> >> > > +
> >> > > +    s->addr = buf[0];
> >> > > +    if (len > 1) {
> >> > > +        sbtsi_write(s, buf[1]);
> >> > > +        if (len > 2) {
> >> > > +            qemu_log_mask(LOG_GUEST_ERROR, "%s: extra data at end\n",
> >> > > __func__);
> >> > > +        }
> >> > > +    }
> >> > > +    return 0;
> >> > > +}
> >> > > +
> >> > > +/* Units are millidegrees. */
> >> > > +static void sbtsi_get_temperature(Object *obj, Visitor *v, const char
> >> > > *name,
> >> > > +                                  void *opaque, Error **errp)
> >> > > +{
> >> > > +    SBTSIState *s = SBTSI(obj);
> >> > > +    uint32_t temp = s->temperature * SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
> >> > > +
> >> > > +    visit_type_uint32(v, name, &temp, errp);
> >> > > +}
> >> > > +
> >> > > +/* Units are millidegrees. */
> >> > > +static void sbtsi_set_temperature(Object *obj, Visitor *v, const char
> >> > > *name,
> >> > > +                                  void *opaque, Error **errp)
> >> > > +{
> >> > > +    SBTSIState *s = SBTSI(obj);
> >> > > +    uint32_t temp;
> >> > > +
> >> > > +    if (!visit_type_uint32(v, name, &temp, errp)) {
> >> > > +        return;
> >> > > +    }
> >> > > +    if (temp > SBTSI_TEMP_MAX) {
> >> > > +        error_setg(errp, "value %" PRIu32 ".%03" PRIu32 " C is out of
> >> > > range",
> >> > > +                   temp / 1000, temp % 1000);
> >> > > +        return;
> >> > > +    }
> >> > > +
> >> > > +    s->temperature = temp / SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
> >> > > +    sbtsi_update_alarm(s);
> >> > > +}
> >> > > +
> >> > > +static int sbtsi_post_load(void *opaque, int version_id)
> >> > > +{
> >> > > +    SBTSIState *s = opaque;
> >> > > +
> >> > > +    sbtsi_update_alarm(s);
> >> > > +    return 0;
> >> > > +}
> >> > > +
> >> > > +static const VMStateDescription vmstate_sbtsi = {
> >> > > +    .name = "SBTSI",
> >> > > +    .version_id = 0,
> >> > > +    .minimum_version_id = 0,
> >> > > +    .post_load = sbtsi_post_load,
> >> > > +    .fields = (VMStateField[]) {
> >> > > +        VMSTATE_UINT32(temperature, SBTSIState),
> >> > > +        VMSTATE_UINT32(limit_low, SBTSIState),
> >> > > +        VMSTATE_UINT32(limit_high, SBTSIState),
> >> > > +        VMSTATE_UINT8(config, SBTSIState),
> >> > > +        VMSTATE_UINT8(status, SBTSIState),
> >> > > +        VMSTATE_UINT8(addr, SBTSIState),
> >> > > +        VMSTATE_END_OF_LIST()
> >> > > +    }
> >> > > +};
> >> > > +
> >> > > +static void sbtsi_enter_reset(Object *obj, ResetType type)
> >> > > +{
> >> > > +    SBTSIState *s = SBTSI(obj);
> >> > > +
> >> > > +    s->config = 0;
> >> > > +    s->limit_low = SBTSI_LIMIT_LOW_DEFAULT;
> >> > > +    s->limit_high = SBTSI_LIMIT_HIGH_DEFAULT;
> >> > > +}
> >> > > +
> >> > > +static void sbtsi_hold_reset(Object *obj)
> >> > > +{
> >> > > +    SBTSIState *s = SBTSI(obj);
> >> > > +
> >> > > +    qemu_irq_lower(s->alarm);
> >> > > +}
> >> > > +
> >> > > +static void sbtsi_init(Object *obj)
> >> > > +{
> >> > > +    SBTSIState *s = SBTSI(obj);
> >> > > +
> >> > > +    /* Current temperature in millidegrees. */
> >> > > +    object_property_add(obj, "temperature", "uint32",
> >> > > +                        sbtsi_get_temperature, sbtsi_set_temperature,
> >> > > +                        NULL, NULL);
> >> > > +    qdev_init_gpio_out_named(DEVICE(obj), &s->alarm, SBTSI_ALARM_L,
> >> 0);
> >> > > +}
> >> > > +
> >> > > +static void sbtsi_class_init(ObjectClass *klass, void *data)
> >> > > +{
> >> > > +    ResettableClass *rc = RESETTABLE_CLASS(klass);
> >> > > +    DeviceClass *dc = DEVICE_CLASS(klass);
> >> > > +    SMBusDeviceClass *k = SMBUS_DEVICE_CLASS(klass);
> >> > > +
> >> > > +    dc->desc = "SB-TSI Temperature Sensor";
> >> > > +    dc->vmsd = &vmstate_sbtsi;
> >> > > +    k->write_data = sbtsi_write_data;
> >> > > +    k->receive_byte = sbtsi_read_byte;
> >> > > +    rc->phases.enter = sbtsi_enter_reset;
> >> > > +    rc->phases.hold = sbtsi_hold_reset;
> >> > > +}
> >> > > +
> >> > > +static const TypeInfo sbtsi_info = {
> >> > > +    .name          = TYPE_SBTSI,
> >> > > +    .parent        = TYPE_SMBUS_DEVICE,
> >> > > +    .instance_size = sizeof(SBTSIState),
> >> > > +    .instance_init = sbtsi_init,
> >> > > +    .class_init    = sbtsi_class_init,
> >> > > +};
> >> > > +
> >> > > +static void sbtsi_register_types(void)
> >> > > +{
> >> > > +    type_register_static(&sbtsi_info);
> >> > > +}
> >> > > +
> >> > > +type_init(sbtsi_register_types)
> >> > > diff --git a/hw/sensor/trace-events b/hw/sensor/trace-events
> >> > > new file mode 100644
> >> > > index 0000000000..21ab3809e2
> >> > > --- /dev/null
> >> > > +++ b/hw/sensor/trace-events
> >> > > @@ -0,0 +1,5 @@
> >> > > +# See docs/devel/tracing.rst for syntax documentation.
> >> > > +
> >> > > +# tmp_sbtsi.c
> >> > > +tmp_sbtsi_write_data(uint8_t addr, uint8_t value) "SBTSI write
> >> > > addr:0x%02x data: 0x%02x"
> >> > > +tmp_sbtsi_read_data(uint8_t addr, uint8_t value) "SBTSI read
> >> addr:0x%02x
> >> > > data: 0x%02x"
> >> > > diff --git a/hw/sensor/trace.h b/hw/sensor/trace.h
> >> > > new file mode 100644
> >> > > index 0000000000..e4721560b0
> >> > > --- /dev/null
> >> > > +++ b/hw/sensor/trace.h
> >> > > @@ -0,0 +1 @@
> >> > > +#include "trace/trace-hw_sensor.h"
> >> > > diff --git a/meson.build b/meson.build
> >> > > index 53065e96ec..f8ab0bf74e 100644
> >> > > --- a/meson.build
> >> > > +++ b/meson.build
> >> > > @@ -2494,6 +2494,7 @@ if have_system
> >> > >      'hw/rtc',
> >> > >      'hw/s390x',
> >> > >      'hw/scsi',
> >> > > +    'hw/sensor',
> >> > >      'hw/sd',
> >> > >      'hw/sh4',
> >> > >      'hw/sparc',
> >> > > diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
> >> > > index 37e1eaa449..d1a8c38f74 100644
> >> > > --- a/tests/qtest/meson.build
> >> > > +++ b/tests/qtest/meson.build
> >> > > @@ -254,6 +254,7 @@ qos_test_ss.add(
> >> > >    'spapr-phb-test.c',
> >> > >    'tmp105-test.c',
> >> > >    'emc141x-test.c',
> >> > > +  'tmp_sbtsi-test.c',
> >> > >    'usb-hcd-ohci-test.c',
> >> > >    'virtio-test.c',
> >> > >    'virtio-blk-test.c',
> >> > > diff --git a/tests/qtest/tmp_sbtsi-test.c
> >> b/tests/qtest/tmp_sbtsi-test.c
> >> > > new file mode 100644
> >> > > index 0000000000..7f5fafacc7
> >> > > --- /dev/null
> >> > > +++ b/tests/qtest/tmp_sbtsi-test.c
> >> > > @@ -0,0 +1,180 @@
> >> > > +/*
> >> > > + * QTests for the SBTSI temperature sensor
> >> > > + *
> >> > > + * Copyright 2020 Google LLC
> >> > > + *
> >> > > + * This program is free software; you can redistribute it and/or
> >> modify it
> >> > > + * under the terms of the GNU General Public License as published by
> >> the
> >> > > + * Free Software Foundation; either version 2 of the License, or
> >> > > + * (at your option) any later version.
> >> > > + *
> >> > > + * This program is distributed in the hope that it will be useful,
> >> but
> >> > > WITHOUT
> >> > > + * ANY WARRANTY; without even the implied warranty of
> >> MERCHANTABILITY or
> >> > > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
> >> License
> >> > > + * for more details.
> >> > > + */
> >> > > +
> >> > > +#include "qemu/osdep.h"
> >> > > +
> >> > > +#include "libqtest-single.h"
> >> > > +#include "libqos/qgraph.h"
> >> > > +#include "libqos/i2c.h"
> >> > > +#include "qapi/qmp/qdict.h"
> >> > > +#include "qemu/bitops.h"
> >> > > +
> >> > > +#define TEST_ID   "sbtsi-test"
> >> > > +#define TEST_ADDR (0x4c)
> >> > > +
> >> > > +/*
> >> > > + * SB-TSI registers only support SMBus byte data access. "_INT"
> >> registers
> >> > > are
> >> > > + * the integer part of a temperature value or limit, and "_DEC"
> >> registers
> >> > > are
> >> > > + * corresponding decimal parts.
> >> > > + */
> >> > > +#define REG_TEMP_INT      0x01 /* RO */
> >> > > +#define REG_STATUS        0x02 /* RO */
> >> > > +#define REG_CONFIG        0x03 /* RO */
> >> > > +#define REG_TEMP_HIGH_INT 0x07 /* RW */
> >> > > +#define REG_TEMP_LOW_INT  0x08 /* RW */
> >> > > +#define REG_CONFIG_WR     0x09 /* RW */
> >> > > +#define REG_TEMP_DEC      0x10 /* RO */
> >> > > +#define REG_TEMP_HIGH_DEC 0x13 /* RW */
> >> > > +#define REG_TEMP_LOW_DEC  0x14 /* RW */
> >> > > +#define REG_ALERT_CONFIG  0xBF /* RW */
> >> > > +
> >> > > +#define STATUS_HIGH_ALERT BIT(4)
> >> > > +#define STATUS_LOW_ALERT  BIT(3)
> >> > > +#define CONFIG_ALERT_MASK BIT(7)
> >> > > +#define ALARM_EN          BIT(0)
> >> > > +
> >> > > +/* The temperature stored are in units of 0.125 degrees. */
> >> > > +#define TEMP_UNIT_IN_MILLIDEGREE 125
> >> > > +#define LIMIT_LOW (10500)
> >> > > +#define LIMIT_HIGH (55125)
> >> > > +
> >> > > +static uint32_t qmp_sbtsi_get_temperature(const char *id)
> >> > > +{
> >> > > +    QDict *response;
> >> > > +    int ret;
> >> > > +
> >> > > +    response = qmp("{ 'execute': 'qom-get', 'arguments': { 'path':
> >> %s, "
> >> > > +                   "'property': 'temperature' } }", id);
> >> > > +    g_assert(qdict_haskey(response, "return"));
> >> > > +    ret = (uint32_t)qdict_get_int(response, "return");
> >> > > +    qobject_unref(response);
> >> > > +    return ret;
> >> > > +}
> >> > > +
> >> > > +static void qmp_sbtsi_set_temperature(const char *id, uint32_t value)
> >> > > +{
> >> > > +    QDict *response;
> >> > > +
> >> > > +    response = qmp("{ 'execute': 'qom-set', 'arguments': { 'path':
> >> %s, "
> >> > > +                   "'property': 'temperature', 'value': %d } }", id,
> >> > > value);
> >> > > +    g_assert(qdict_haskey(response, "return"));
> >> > > +    qobject_unref(response);
> >> > > +}
> >> > > +
> >> > > +/*
> >> > > + * Compute the temperature using the integer and decimal part and
> >> return
> >> > > + * millidegrees. The decimal part are only the top 3 bits so we
> >> shift it
> >> > > by
> >> > > + * 5 here.
> >> > > + */
> >> > > +static uint32_t regs_to_temp(uint8_t integer, uint8_t decimal)
> >> > > +{
> >> > > +    return ((integer << 3) + (decimal >> 5)) *
> >> TEMP_UNIT_IN_MILLIDEGREE;
> >> > > +}
> >> > > +
> >> > > +/*
> >> > > + * Compute the integer and decimal parts of the temperature in
> >> > > millidegrees.
> >> > > + * H/W store the decimal in the top 3 bits so we shift it by 5.
> >> > > + */
> >> > > +static void temp_to_regs(uint32_t temp, uint8_t *integer, uint8_t
> >> > > *decimal)
> >> > > +{
> >> > > +    temp /= TEMP_UNIT_IN_MILLIDEGREE;
> >> > > +    *integer = temp >> 3;
> >> > > +    *decimal = (temp & 0x7) << 5;
> >> > > +}
> >> > > +
> >> > > +static void tx_rx(void *obj, void *data, QGuestAllocator *alloc)
> >> > > +{
> >> > > +    uint16_t value;
> >> > > +    uint8_t integer, decimal;
> >> > > +    QI2CDevice *i2cdev = (QI2CDevice *)obj;
> >> > > +
> >> > > +    /* Test default values */
> >> > > +    value = qmp_sbtsi_get_temperature(TEST_ID);
> >> > > +    g_assert_cmpuint(value, ==, 0);
> >> > > +
> >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
> >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
> >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 0);
> >> > > +
> >> > > +    /* Test setting temperature */
> >> > > +    qmp_sbtsi_set_temperature(TEST_ID, 20000);
> >> > > +    value = qmp_sbtsi_get_temperature(TEST_ID);
> >> > > +    g_assert_cmpuint(value, ==, 20000);
> >> > > +
> >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
> >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
> >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 20000);
> >> > > +
> >> > > +    /* Set alert mask in config */
> >> > > +    i2c_set8(i2cdev, REG_CONFIG_WR, CONFIG_ALERT_MASK);
> >> > > +    value = i2c_get8(i2cdev, REG_CONFIG);
> >> > > +    g_assert_cmphex(value, ==, CONFIG_ALERT_MASK);
> >> > > +    /* Enable alarm_en */
> >> > > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, ALARM_EN);
> >> > > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
> >> > > +    g_assert_cmphex(value, ==, ALARM_EN);
> >> > > +
> >> > > +    /* Test setting limits */
> >> > > +    /* Limit low = 10.500 */
> >> > > +    temp_to_regs(LIMIT_LOW, &integer, &decimal);
> >> > > +    i2c_set8(i2cdev, REG_TEMP_LOW_INT, integer);
> >> > > +    i2c_set8(i2cdev, REG_TEMP_LOW_DEC, decimal);
> >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_LOW_INT);
> >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_LOW_DEC);
> >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, LIMIT_LOW);
> >> > > +    /* Limit high = 55.125 */
> >> > > +    temp_to_regs(LIMIT_HIGH, &integer, &decimal);
> >> > > +    i2c_set8(i2cdev, REG_TEMP_HIGH_INT, integer);
> >> > > +    i2c_set8(i2cdev, REG_TEMP_HIGH_DEC, decimal);
> >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_HIGH_INT);
> >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_HIGH_DEC);
> >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, LIMIT_HIGH);
> >> > > +    /* No alert is generated. */
> >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> >> > > +    g_assert_cmphex(value, ==, 0);
> >> > > +
> >> > > +    /* Test alert for low temperature */
> >> > > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_LOW);
> >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> >> > > +    g_assert_cmphex(value, ==, STATUS_LOW_ALERT);
> >> > > +
> >> > > +    /* Test alert for high temperature */
> >> > > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_HIGH);
> >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> >> > > +    g_assert_cmphex(value, ==, STATUS_HIGH_ALERT);
> >> > > +
> >> > > +    /* Disable alarm_en */
> >> > > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, 0);
> >> > > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
> >> > > +    g_assert_cmphex(value, ==, 0);
> >> > > +    /* No alert when alarm_en is false. */
> >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> >> > > +    g_assert_cmphex(value, ==, 0);
> >> > > +}
> >> > > +
> >> > > +static void sbtsi_register_nodes(void)
> >> > > +{
> >> > > +    QOSGraphEdgeOptions opts = {
> >> > > +        .extra_device_opts = "id=" TEST_ID ",address=0x4c"
> >> > > +    };
> >> > > +    add_qi2c_address(&opts, &(QI2CAddress) { TEST_ADDR });
> >> > > +
> >> > > +    qos_node_create_driver("sbtsi", i2c_device_create);
> >> > > +    qos_node_consumes("sbtsi", "i2c-bus", &opts);
> >> > > +
> >> > > +    qos_add_test("tx-rx", "sbtsi", tx_rx, NULL);
> >> > > +}
> >> > > +libqos_init(sbtsi_register_nodes);
> >> > > --
> >> >
> >> >
> >> > + Corey for i2c maintainer.  The new sensor directory is mostly if not
> >> > entirely i2c devices.  I didn't create a maintainer entry for this i2c
> >> > device, but I can if desired and send out a v2.
> >>
> >> Yeah, I guess I should be maintainer there.  I'll queue up a change for
> >> that.  Thanks.
> >>
> >> -corey
> >>
> >> >
> >> >
> >> > > 2.34.1.575.g55b058a8bb-goog
> >> > >
> >> > >
> >>
> >

Hao Wu Jan. 27, 2022, 6:19 p.m. UTC | #11

On Thu, Jan 27, 2022 at 6:55 AM Corey Minyard <[e-mail]> wrote:

> On Wed, Jan 26, 2022 at 04:09:03PM -0800, Hao Wu wrote:
> > Hi,
> >
> > Sorry for the late reply. I'm not sure what "auto-increment" means here.
>
> The question is: When a value is read, does the address automatically
> increment.  I2C devices very often do this.  If you do a multi-byte
> read, they often will read the value from address 0, then from address
> 1, etc.  Same for writes.
>
The datasheet does not suggest such behavior could happen.

>
> > The kernel driver at
> > https://lkml.org/lkml/2020/12/11/968
> > only has byte-size read/write operations, so I don't see a problem here.
> > The values are extracted
> > from the datasheet.
>
> The *Linux* kernel driver my only do byte-size operations, but other
> kernels may work different, and the Linux kernel may change.  You have
> to implement from the datasheet, not the device driver.
>
The implementation is already according to the datasheet.

> Thanks,
>
> -corey
>
> >
> > On Tue, Jan 18, 2022 at 9:10 AM Patrick Venture <[e-mail]>
> wrote:
> >
> > >
> > >
> > > On Mon, Jan 17, 2022 at 6:05 AM Corey Minyard <[e-mail]>
> wrote:
> > >
> > >> On Sun, Jan 09, 2022 at 06:17:34PM -0800, Patrick Venture wrote:
> > >> > On Fri, Jan 7, 2022 at 7:04 PM Patrick Venture <[e-mail]>
> > >> wrote:
> > >> >
> > >> > > From: Hao Wu <[e-mail]>
> > >> > >
> > >> > > SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
> > >> > > interface that reports AMD SoC's Ttcl (normalized temperature),
> > >> > > and resembles a typical 8-pin remote temperature sensor's I2C
> > >> interface
> > >> > > to BMC.
> > >> > >
> > >> > > This patch implements a basic AMD SB-TSI sensor that is
> > >> > > compatible with the open-source data sheet from AMD and Linux
> > >> > > kernel driver.
> > >> > >
> > >> > > Reference:
> > >> > > Linux kernel driver:
> > >> > > https://lkml.org/lkml/2020/12/11/968
> > >> > > Register Map:
> > >> > > https://developer.amd.com/wp-content/resources/56255_3_03.PDF
> > >> > > (Chapter 6)
> > >> > >
> > >> > > Signed-off-by: Hao Wu <[e-mail]>
> > >> > > Reviewed-by: Doug Evans <[e-mail]>
> > >> > > ---
> > >> > >  hw/sensor/Kconfig            |   4 +
> > >> > >  hw/sensor/meson.build        |   1 +
> > >> > >  hw/sensor/tmp_sbtsi.c        | 393
> > >> +++++++++++++++++++++++++++++++++++
> > >> > >  hw/sensor/trace-events       |   5 +
> > >> > >  hw/sensor/trace.h            |   1 +
> > >> > >  meson.build                  |   1 +
> > >> > >  tests/qtest/meson.build      |   1 +
> > >> > >  tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++
> > >> > >  8 files changed, 586 insertions(+)
> > >> > >  create mode 100644 hw/sensor/tmp_sbtsi.c
> > >> > >  create mode 100644 hw/sensor/trace-events
> > >> > >  create mode 100644 hw/sensor/trace.h
> > >> > >  create mode 100644 tests/qtest/tmp_sbtsi-test.c
> > >> > >
> > >> > > diff --git a/hw/sensor/Kconfig b/hw/sensor/Kconfig
> > >> > > index 9c8a049b06..27f6f79c84 100644
> > >> > > --- a/hw/sensor/Kconfig
> > >> > > +++ b/hw/sensor/Kconfig
> > >> > > @@ -21,3 +21,7 @@ config ADM1272
> > >> > >  config MAX34451
> > >> > >      bool
> > >> > >      depends on I2C
> > >> > > +
> > >> > > +config AMDSBTSI
> > >> > > +    bool
> > >> > > +    depends on I2C
> > >> > > diff --git a/hw/sensor/meson.build b/hw/sensor/meson.build
> > >> > > index 059c4ca935..f7b0e645eb 100644
> > >> > > --- a/hw/sensor/meson.build
> > >> > > +++ b/hw/sensor/meson.build
> > >> > > @@ -4,3 +4,4 @@ softmmu_ss.add(when: 'CONFIG_DPS310', if_true:
> > >> > > files('dps310.c'))
> > >> > >  softmmu_ss.add(when: 'CONFIG_EMC141X', if_true:
> files('emc141x.c'))
> > >> > >  softmmu_ss.add(when: 'CONFIG_ADM1272', if_true:
> files('adm1272.c'))
> > >> > >  softmmu_ss.add(when: 'CONFIG_MAX34451', if_true:
> files('max34451.c'))
> > >> > > +softmmu_ss.add(when: 'CONFIG_AMDSBTSI', if_true:
> > >> files('tmp_sbtsi.c'))
> > >> > > diff --git a/hw/sensor/tmp_sbtsi.c b/hw/sensor/tmp_sbtsi.c
> > >> > > new file mode 100644
> > >> > > index 0000000000..b68c7ebf61
> > >> > > --- /dev/null
> > >> > > +++ b/hw/sensor/tmp_sbtsi.c
> > >> > > @@ -0,0 +1,393 @@
> > >> > > +/*
> > >> > > + * AMD SBI Temperature Sensor Interface (SB-TSI)
> > >> > > + *
> > >> > > + * Copyright 2021 Google LLC
> > >> > > + *
> > >> > > + * This program is free software; you can redistribute it and/or
> > >> modify it
> > >> > > + * under the terms of the GNU General Public License as
> published by
> > >> the
> > >> > > + * Free Software Foundation; either version 2 of the License, or
> > >> > > + * (at your option) any later version.
> > >> > > + *
> > >> > > + * This program is distributed in the hope that it will be
> useful,
> > >> but
> > >> > > WITHOUT
> > >> > > + * ANY WARRANTY; without even the implied warranty of
> > >> MERCHANTABILITY or
> > >> > > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
> > >> License
> > >> > > + * for more details.
> > >> > > + */
> > >> > > +
> > >> > > +#include "qemu/osdep.h"
> > >> > > +#include "hw/i2c/smbus_slave.h"
> > >> > > +#include "hw/irq.h"
> > >> > > +#include "migration/vmstate.h"
> > >> > > +#include "qapi/error.h"
> > >> > > +#include "qapi/visitor.h"
> > >> > > +#include "qemu/log.h"
> > >> > > +#include "qemu/module.h"
> > >> > > +#include "trace.h"
> > >> > > +
> > >> > > +#define TYPE_SBTSI "sbtsi"
> > >> > > +#define SBTSI(obj) OBJECT_CHECK(SBTSIState, (obj), TYPE_SBTSI)
> > >> > > +
> > >> > > +/**
> > >> > > + * SBTSIState:
> > >> > > + * temperatures are in units of 0.125 degrees
> > >> > > + * @temperature: Temperature
> > >> > > + * @limit_low: Lowest temperature
> > >> > > + * @limit_high: Highest temperature
> > >> > > + * @status: The status register
> > >> > > + * @config: The config register
> > >> > > + * @alert_config: The config for alarm_l output.
> > >> > > + * @addr: The address to read/write for the next cmd.
> > >> > > + * @alarm: The alarm_l output pin (GPIO)
> > >> > > + */
> > >> > > +typedef struct SBTSIState {
> > >> > > +    SMBusDevice parent;
> > >> > > +
> > >> > > +    uint32_t temperature;
> > >> > > +    uint32_t limit_low;
> > >> > > +    uint32_t limit_high;
> > >> > > +    uint8_t status;
> > >> > > +    uint8_t config;
> > >> > > +    uint8_t alert_config;
> > >> > > +    uint8_t addr;
> > >> > > +    qemu_irq alarm;
> > >> > > +} SBTSIState;
> > >> > > +
> > >> > > +/*
> > >> > > + * SB-TSI registers only support SMBus byte data access. "_INT"
> > >> registers
> > >> > > are
> > >> > > + * the integer part of a temperature value or limit, and "_DEC"
> > >> registers
> > >> > > are
> > >> > > + * corresponding decimal parts.
> > >> > > + */
> > >> > > +#define SBTSI_REG_TEMP_INT      0x01 /* RO */
> > >> > > +#define SBTSI_REG_STATUS        0x02 /* RO */
> > >> > > +#define SBTSI_REG_CONFIG        0x03 /* RO */
> > >> > > +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */
> > >> > > +#define SBTSI_REG_TEMP_LOW_INT  0x08 /* RW */
> > >> > > +#define SBTSI_REG_CONFIG_WR     0x09 /* RW */
> > >> > > +#define SBTSI_REG_TEMP_DEC      0x10 /* RO */
> > >> > > +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */
> > >> > > +#define SBTSI_REG_TEMP_LOW_DEC  0x14 /* RW */
> > >> > > +#define SBTSI_REG_ALERT_CONFIG  0xBF /* RW */
> > >> > > +#define SBTSI_REG_MAN           0xFE /* RO */
> > >> > > +#define SBTSI_REG_REV           0xFF /* RO */
> > >> > > +
> > >> > > +#define SBTSI_STATUS_HIGH_ALERT BIT(4)
> > >> > > +#define SBTSI_STATUS_LOW_ALERT  BIT(3)
> > >> > > +#define SBTSI_CONFIG_ALERT_MASK BIT(7)
> > >> > > +#define SBTSI_ALARM_EN          BIT(0)
> > >> > > +
> > >> > > +#define SBTSI_LIMIT_LOW_DEFAULT (0)
> > >> > > +#define SBTSI_LIMIT_HIGH_DEFAULT (560)
> > >> > > +#define SBTSI_MAN_DEFAULT (0)
> > >> > > +#define SBTSI_REV_DEFAULT (4)
> > >> > > +#define SBTSI_ALARM_L "alarm_l"
> > >> > > +
> > >> > > +/* The temperature we stored are in units of 0.125 degrees. */
> > >> > > +#define SBTSI_TEMP_UNIT_IN_MILLIDEGREE 125
> > >> > > +
> > >> > > +/*
> > >> > > + * The integer part and decimal of the temperature both 8 bits.
> > >> > > + * Only the top 3 bits of the decimal parts are used.
> > >> > > + * So the max temperature is (2^8-1) + (2^3-1)/8 = 255.875
> degrees.
> > >> > > + */
> > >> > > +#define SBTSI_TEMP_MAX 255875
> > >> > > +
> > >> > > +/* The integer part of the temperature in terms of 0.125
> degrees. */
> > >> > > +static uint8_t get_temp_int(uint32_t temp)
> > >> > > +{
> > >> > > +    return temp >> 3;
> > >> > > +}
> > >> > > +
> > >> > > +/*
> > >> > > + * The decimal part of the temperature, in terms of 0.125
> degrees.
> > >> > > + * H/W store it in the top 3 bits so we shift it by 5.
> > >> > > + */
> > >> > > +static uint8_t get_temp_dec(uint32_t temp)
> > >> > > +{
> > >> > > +    return (temp & 0x7) << 5;
> > >> > > +}
> > >> > > +
> > >> > > +/*
> > >> > > + * Compute the temperature using the integer and decimal part,
> > >> > > + * in terms of 0.125 degrees. The decimal part are only the top 3
> > >> bits
> > >> > > + * so we shift it by 5 here.
> > >> > > + */
> > >> > > +static uint32_t compute_temp(uint8_t integer, uint8_t decimal)
> > >> > > +{
> > >> > > +    return (integer << 3) + (decimal >> 5);
> > >> > > +}
> > >> > > +
> > >> > > +/* Compute new temp with new int part of the temperature. */
> > >> > > +static uint32_t compute_temp_int(uint32_t temp, uint8_t integer)
> > >> > > +{
> > >> > > +    return compute_temp(integer, get_temp_dec(temp));
> > >> > > +}
> > >> > > +
> > >> > > +/* Compute new temp with new dec part of the temperature. */
> > >> > > +static uint32_t compute_temp_dec(uint32_t temp, uint8_t decimal)
> > >> > > +{
> > >> > > +    return compute_temp(get_temp_int(temp), decimal);
> > >> > > +}
> > >> > > +
> > >> > > +/* The integer part of the temperature. */
> > >> > > +static void sbtsi_update_status(SBTSIState *s)
> > >> > > +{
> > >> > > +    s->status = 0;
> > >> > > +    if (s->alert_config & SBTSI_ALARM_EN) {
> > >> > > +        if (s->temperature >= s->limit_high) {
> > >> > > +            s->status |= SBTSI_STATUS_HIGH_ALERT;
> > >> > > +        }
> > >> > > +        if (s->temperature <= s->limit_low) {
> > >> > > +            s->status |= SBTSI_STATUS_LOW_ALERT;
> > >> > > +        }
> > >> > > +    }
> > >> > > +}
> > >> > > +
> > >> > > +static void sbtsi_update_alarm(SBTSIState *s)
> > >> > > +{
> > >> > > +    sbtsi_update_status(s);
> > >> > > +    if (s->status != 0 && !(s->config &
> SBTSI_CONFIG_ALERT_MASK)) {
> > >> > > +        qemu_irq_raise(s->alarm);
> > >> > > +    } else {
> > >> > > +        qemu_irq_lower(s->alarm);
> > >> > > +    }
> > >> > > +}
> > >> > > +
> > >> > > +static uint8_t sbtsi_read_byte(SMBusDevice *d)
> > >> > > +{
> > >> > > +    SBTSIState *s = SBTSI(d);
> > >> > > +    uint8_t data = 0;
> > >> > > +
> > >> > > +    switch (s->addr) {
> > >> > > +    case SBTSI_REG_TEMP_INT:
> > >> > > +        data = get_temp_int(s->temperature);
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_TEMP_DEC:
> > >> > > +        data = get_temp_dec(s->temperature);
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_TEMP_HIGH_INT:
> > >> > > +        data = get_temp_int(s->limit_high);
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_TEMP_LOW_INT:
> > >> > > +        data = get_temp_int(s->limit_low);
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_TEMP_HIGH_DEC:
> > >> > > +        data = get_temp_dec(s->limit_high);
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_TEMP_LOW_DEC:
> > >> > > +        data = get_temp_dec(s->limit_low);
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_CONFIG:
> > >> > > +    case SBTSI_REG_CONFIG_WR:
> > >> > > +        data = s->config;
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_STATUS:
> > >> > > +        sbtsi_update_alarm(s);
> > >> > > +        data = s->status;
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_ALERT_CONFIG:
> > >> > > +        data = s->alert_config;
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_MAN:
> > >> > > +        data = SBTSI_MAN_DEFAULT;
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_REV:
> > >> > > +        data = SBTSI_REV_DEFAULT;
> > >> > > +        break;
> > >>
> > >> Does this device do some sort of auto-increment on the address when
> > >> reading/writing?
> > >>
> > >
> > > +Hao Wu <[e-mail]>   - Please take a look at the above
> > > question.  I imagine it's a while since you've thought about it, but
> please
> > > double check :)
> > > Thanks!
> > >
> > >
> > >> Other than that possible issue, I don't see anything else, it's pretty
> > >> straightforward.
> > >>
> > >> > > +
> > >> > > +    default:
> > >> > > +        qemu_log_mask(LOG_GUEST_ERROR,
> > >> > > +                "%s: reading from invalid reg: 0x%02x\n",
> > >> > > +                __func__, s->addr);
> > >> > > +        break;
> > >> > > +    }
> > >> > > +
> > >> > > +    trace_tmp_sbtsi_read_data(s->addr, data);
> > >> > > +    return data;
> > >> > > +}
> > >> > > +
> > >> > > +static void sbtsi_write(SBTSIState *s, uint8_t data)
> > >> > > +{
> > >> > > +    trace_tmp_sbtsi_write_data(s->addr, data);
> > >> > > +    switch (s->addr) {
> > >> > > +    case SBTSI_REG_CONFIG_WR:
> > >> > > +        s->config = data;
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_TEMP_HIGH_INT:
> > >> > > +        s->limit_high = compute_temp_int(s->limit_high, data);
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_TEMP_LOW_INT:
> > >> > > +        s->limit_low = compute_temp_int(s->limit_low, data);
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_TEMP_HIGH_DEC:
> > >> > > +        s->limit_high = compute_temp_dec(s->limit_high, data);
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_TEMP_LOW_DEC:
> > >> > > +        s->limit_low = compute_temp_dec(s->limit_low, data);
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_ALERT_CONFIG:
> > >> > > +        s->alert_config = data;
> > >> > > +        break;
> > >> > > +
> > >> > > +    case SBTSI_REG_TEMP_INT:
> > >> > > +    case SBTSI_REG_TEMP_DEC:
> > >> > > +    case SBTSI_REG_CONFIG:
> > >> > > +    case SBTSI_REG_STATUS:
> > >> > > +    case SBTSI_REG_MAN:
> > >> > > +    case SBTSI_REG_REV:
> > >> > > +        qemu_log_mask(LOG_GUEST_ERROR,
> > >> > > +                "%s: writing to read only reg: 0x%02x data:
> > >> 0x%02x\n",
> > >> > > +                __func__, s->addr, data);
> > >> > > +        break;
> > >> > > +
> > >> > > +    default:
> > >> > > +        qemu_log_mask(LOG_GUEST_ERROR,
> > >> > > +                "%s: writing to invalid reg: 0x%02x data:
> 0x%02x\n",
> > >> > > +                __func__, s->addr, data);
> > >> > > +        break;
> > >> > > +    }
> > >> > > +    sbtsi_update_alarm(s);
> > >> > > +}
> > >> > > +
> > >> > > +static int sbtsi_write_data(SMBusDevice *d, uint8_t *buf, uint8_t
> > >> len)
> > >> > > +{
> > >> > > +    SBTSIState *s = SBTSI(d);
> > >> > > +
> > >> > > +    if (len == 0) {
> > >> > > +        qemu_log_mask(LOG_GUEST_ERROR, "%s: writing empty
> data\n",
> > >> > > __func__);
> > >> > > +        return -1;
> > >> > > +    }
> > >> > > +
> > >> > > +    s->addr = buf[0];
> > >> > > +    if (len > 1) {
> > >> > > +        sbtsi_write(s, buf[1]);
> > >> > > +        if (len > 2) {
> > >> > > +            qemu_log_mask(LOG_GUEST_ERROR, "%s: extra data at
> end\n",
> > >> > > __func__);
> > >> > > +        }
> > >> > > +    }
> > >> > > +    return 0;
> > >> > > +}
> > >> > > +
> > >> > > +/* Units are millidegrees. */
> > >> > > +static void sbtsi_get_temperature(Object *obj, Visitor *v, const
> char
> > >> > > *name,
> > >> > > +                                  void *opaque, Error **errp)
> > >> > > +{
> > >> > > +    SBTSIState *s = SBTSI(obj);
> > >> > > +    uint32_t temp = s->temperature *
> SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
> > >> > > +
> > >> > > +    visit_type_uint32(v, name, &temp, errp);
> > >> > > +}
> > >> > > +
> > >> > > +/* Units are millidegrees. */
> > >> > > +static void sbtsi_set_temperature(Object *obj, Visitor *v, const
> char
> > >> > > *name,
> > >> > > +                                  void *opaque, Error **errp)
> > >> > > +{
> > >> > > +    SBTSIState *s = SBTSI(obj);
> > >> > > +    uint32_t temp;
> > >> > > +
> > >> > > +    if (!visit_type_uint32(v, name, &temp, errp)) {
> > >> > > +        return;
> > >> > > +    }
> > >> > > +    if (temp > SBTSI_TEMP_MAX) {
> > >> > > +        error_setg(errp, "value %" PRIu32 ".%03" PRIu32 " C is
> out of
> > >> > > range",
> > >> > > +                   temp / 1000, temp % 1000);
> > >> > > +        return;
> > >> > > +    }
> > >> > > +
> > >> > > +    s->temperature = temp / SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
> > >> > > +    sbtsi_update_alarm(s);
> > >> > > +}
> > >> > > +
> > >> > > +static int sbtsi_post_load(void *opaque, int version_id)
> > >> > > +{
> > >> > > +    SBTSIState *s = opaque;
> > >> > > +
> > >> > > +    sbtsi_update_alarm(s);
> > >> > > +    return 0;
> > >> > > +}
> > >> > > +
> > >> > > +static const VMStateDescription vmstate_sbtsi = {
> > >> > > +    .name = "SBTSI",
> > >> > > +    .version_id = 0,
> > >> > > +    .minimum_version_id = 0,
> > >> > > +    .post_load = sbtsi_post_load,
> > >> > > +    .fields = (VMStateField[]) {
> > >> > > +        VMSTATE_UINT32(temperature, SBTSIState),
> > >> > > +        VMSTATE_UINT32(limit_low, SBTSIState),
> > >> > > +        VMSTATE_UINT32(limit_high, SBTSIState),
> > >> > > +        VMSTATE_UINT8(config, SBTSIState),
> > >> > > +        VMSTATE_UINT8(status, SBTSIState),
> > >> > > +        VMSTATE_UINT8(addr, SBTSIState),
> > >> > > +        VMSTATE_END_OF_LIST()
> > >> > > +    }
> > >> > > +};
> > >> > > +
> > >> > > +static void sbtsi_enter_reset(Object *obj, ResetType type)
> > >> > > +{
> > >> > > +    SBTSIState *s = SBTSI(obj);
> > >> > > +
> > >> > > +    s->config = 0;
> > >> > > +    s->limit_low = SBTSI_LIMIT_LOW_DEFAULT;
> > >> > > +    s->limit_high = SBTSI_LIMIT_HIGH_DEFAULT;
> > >> > > +}
> > >> > > +
> > >> > > +static void sbtsi_hold_reset(Object *obj)
> > >> > > +{
> > >> > > +    SBTSIState *s = SBTSI(obj);
> > >> > > +
> > >> > > +    qemu_irq_lower(s->alarm);
> > >> > > +}
> > >> > > +
> > >> > > +static void sbtsi_init(Object *obj)
> > >> > > +{
> > >> > > +    SBTSIState *s = SBTSI(obj);
> > >> > > +
> > >> > > +    /* Current temperature in millidegrees. */
> > >> > > +    object_property_add(obj, "temperature", "uint32",
> > >> > > +                        sbtsi_get_temperature,
> sbtsi_set_temperature,
> > >> > > +                        NULL, NULL);
> > >> > > +    qdev_init_gpio_out_named(DEVICE(obj), &s->alarm,
> SBTSI_ALARM_L,
> > >> 0);
> > >> > > +}
> > >> > > +
> > >> > > +static void sbtsi_class_init(ObjectClass *klass, void *data)
> > >> > > +{
> > >> > > +    ResettableClass *rc = RESETTABLE_CLASS(klass);
> > >> > > +    DeviceClass *dc = DEVICE_CLASS(klass);
> > >> > > +    SMBusDeviceClass *k = SMBUS_DEVICE_CLASS(klass);
> > >> > > +
> > >> > > +    dc->desc = "SB-TSI Temperature Sensor";
> > >> > > +    dc->vmsd = &vmstate_sbtsi;
> > >> > > +    k->write_data = sbtsi_write_data;
> > >> > > +    k->receive_byte = sbtsi_read_byte;
> > >> > > +    rc->phases.enter = sbtsi_enter_reset;
> > >> > > +    rc->phases.hold = sbtsi_hold_reset;
> > >> > > +}
> > >> > > +
> > >> > > +static const TypeInfo sbtsi_info = {
> > >> > > +    .name          = TYPE_SBTSI,
> > >> > > +    .parent        = TYPE_SMBUS_DEVICE,
> > >> > > +    .instance_size = sizeof(SBTSIState),
> > >> > > +    .instance_init = sbtsi_init,
> > >> > > +    .class_init    = sbtsi_class_init,
> > >> > > +};
> > >> > > +
> > >> > > +static void sbtsi_register_types(void)
> > >> > > +{
> > >> > > +    type_register_static(&sbtsi_info);
> > >> > > +}
> > >> > > +
> > >> > > +type_init(sbtsi_register_types)
> > >> > > diff --git a/hw/sensor/trace-events b/hw/sensor/trace-events
> > >> > > new file mode 100644
> > >> > > index 0000000000..21ab3809e2
> > >> > > --- /dev/null
> > >> > > +++ b/hw/sensor/trace-events
> > >> > > @@ -0,0 +1,5 @@
> > >> > > +# See docs/devel/tracing.rst for syntax documentation.
> > >> > > +
> > >> > > +# tmp_sbtsi.c
> > >> > > +tmp_sbtsi_write_data(uint8_t addr, uint8_t value) "SBTSI write
> > >> > > addr:0x%02x data: 0x%02x"
> > >> > > +tmp_sbtsi_read_data(uint8_t addr, uint8_t value) "SBTSI read
> > >> addr:0x%02x
> > >> > > data: 0x%02x"
> > >> > > diff --git a/hw/sensor/trace.h b/hw/sensor/trace.h
> > >> > > new file mode 100644
> > >> > > index 0000000000..e4721560b0
> > >> > > --- /dev/null
> > >> > > +++ b/hw/sensor/trace.h
> > >> > > @@ -0,0 +1 @@
> > >> > > +#include "trace/trace-hw_sensor.h"
> > >> > > diff --git a/meson.build b/meson.build
> > >> > > index 53065e96ec..f8ab0bf74e 100644
> > >> > > --- a/meson.build
> > >> > > +++ b/meson.build
> > >> > > @@ -2494,6 +2494,7 @@ if have_system
> > >> > >      'hw/rtc',
> > >> > >      'hw/s390x',
> > >> > >      'hw/scsi',
> > >> > > +    'hw/sensor',
> > >> > >      'hw/sd',
> > >> > >      'hw/sh4',
> > >> > >      'hw/sparc',
> > >> > > diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
> > >> > > index 37e1eaa449..d1a8c38f74 100644
> > >> > > --- a/tests/qtest/meson.build
> > >> > > +++ b/tests/qtest/meson.build
> > >> > > @@ -254,6 +254,7 @@ qos_test_ss.add(
> > >> > >    'spapr-phb-test.c',
> > >> > >    'tmp105-test.c',
> > >> > >    'emc141x-test.c',
> > >> > > +  'tmp_sbtsi-test.c',
> > >> > >    'usb-hcd-ohci-test.c',
> > >> > >    'virtio-test.c',
> > >> > >    'virtio-blk-test.c',
> > >> > > diff --git a/tests/qtest/tmp_sbtsi-test.c
> > >> b/tests/qtest/tmp_sbtsi-test.c
> > >> > > new file mode 100644
> > >> > > index 0000000000..7f5fafacc7
> > >> > > --- /dev/null
> > >> > > +++ b/tests/qtest/tmp_sbtsi-test.c
> > >> > > @@ -0,0 +1,180 @@
> > >> > > +/*
> > >> > > + * QTests for the SBTSI temperature sensor
> > >> > > + *
> > >> > > + * Copyright 2020 Google LLC
> > >> > > + *
> > >> > > + * This program is free software; you can redistribute it and/or
> > >> modify it
> > >> > > + * under the terms of the GNU General Public License as
> published by
> > >> the
> > >> > > + * Free Software Foundation; either version 2 of the License, or
> > >> > > + * (at your option) any later version.
> > >> > > + *
> > >> > > + * This program is distributed in the hope that it will be
> useful,
> > >> but
> > >> > > WITHOUT
> > >> > > + * ANY WARRANTY; without even the implied warranty of
> > >> MERCHANTABILITY or
> > >> > > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
> > >> License
> > >> > > + * for more details.
> > >> > > + */
> > >> > > +
> > >> > > +#include "qemu/osdep.h"
> > >> > > +
> > >> > > +#include "libqtest-single.h"
> > >> > > +#include "libqos/qgraph.h"
> > >> > > +#include "libqos/i2c.h"
> > >> > > +#include "qapi/qmp/qdict.h"
> > >> > > +#include "qemu/bitops.h"
> > >> > > +
> > >> > > +#define TEST_ID   "sbtsi-test"
> > >> > > +#define TEST_ADDR (0x4c)
> > >> > > +
> > >> > > +/*
> > >> > > + * SB-TSI registers only support SMBus byte data access. "_INT"
> > >> registers
> > >> > > are
> > >> > > + * the integer part of a temperature value or limit, and "_DEC"
> > >> registers
> > >> > > are
> > >> > > + * corresponding decimal parts.
> > >> > > + */
> > >> > > +#define REG_TEMP_INT      0x01 /* RO */
> > >> > > +#define REG_STATUS        0x02 /* RO */
> > >> > > +#define REG_CONFIG        0x03 /* RO */
> > >> > > +#define REG_TEMP_HIGH_INT 0x07 /* RW */
> > >> > > +#define REG_TEMP_LOW_INT  0x08 /* RW */
> > >> > > +#define REG_CONFIG_WR     0x09 /* RW */
> > >> > > +#define REG_TEMP_DEC      0x10 /* RO */
> > >> > > +#define REG_TEMP_HIGH_DEC 0x13 /* RW */
> > >> > > +#define REG_TEMP_LOW_DEC  0x14 /* RW */
> > >> > > +#define REG_ALERT_CONFIG  0xBF /* RW */
> > >> > > +
> > >> > > +#define STATUS_HIGH_ALERT BIT(4)
> > >> > > +#define STATUS_LOW_ALERT  BIT(3)
> > >> > > +#define CONFIG_ALERT_MASK BIT(7)
> > >> > > +#define ALARM_EN          BIT(0)
> > >> > > +
> > >> > > +/* The temperature stored are in units of 0.125 degrees. */
> > >> > > +#define TEMP_UNIT_IN_MILLIDEGREE 125
> > >> > > +#define LIMIT_LOW (10500)
> > >> > > +#define LIMIT_HIGH (55125)
> > >> > > +
> > >> > > +static uint32_t qmp_sbtsi_get_temperature(const char *id)
> > >> > > +{
> > >> > > +    QDict *response;
> > >> > > +    int ret;
> > >> > > +
> > >> > > +    response = qmp("{ 'execute': 'qom-get', 'arguments': {
> 'path':
> > >> %s, "
> > >> > > +                   "'property': 'temperature' } }", id);
> > >> > > +    g_assert(qdict_haskey(response, "return"));
> > >> > > +    ret = (uint32_t)qdict_get_int(response, "return");
> > >> > > +    qobject_unref(response);
> > >> > > +    return ret;
> > >> > > +}
> > >> > > +
> > >> > > +static void qmp_sbtsi_set_temperature(const char *id, uint32_t
> value)
> > >> > > +{
> > >> > > +    QDict *response;
> > >> > > +
> > >> > > +    response = qmp("{ 'execute': 'qom-set', 'arguments': {
> 'path':
> > >> %s, "
> > >> > > +                   "'property': 'temperature', 'value': %d } }",
> id,
> > >> > > value);
> > >> > > +    g_assert(qdict_haskey(response, "return"));
> > >> > > +    qobject_unref(response);
> > >> > > +}
> > >> > > +
> > >> > > +/*
> > >> > > + * Compute the temperature using the integer and decimal part and
> > >> return
> > >> > > + * millidegrees. The decimal part are only the top 3 bits so we
> > >> shift it
> > >> > > by
> > >> > > + * 5 here.
> > >> > > + */
> > >> > > +static uint32_t regs_to_temp(uint8_t integer, uint8_t decimal)
> > >> > > +{
> > >> > > +    return ((integer << 3) + (decimal >> 5)) *
> > >> TEMP_UNIT_IN_MILLIDEGREE;
> > >> > > +}
> > >> > > +
> > >> > > +/*
> > >> > > + * Compute the integer and decimal parts of the temperature in
> > >> > > millidegrees.
> > >> > > + * H/W store the decimal in the top 3 bits so we shift it by 5.
> > >> > > + */
> > >> > > +static void temp_to_regs(uint32_t temp, uint8_t *integer, uint8_t
> > >> > > *decimal)
> > >> > > +{
> > >> > > +    temp /= TEMP_UNIT_IN_MILLIDEGREE;
> > >> > > +    *integer = temp >> 3;
> > >> > > +    *decimal = (temp & 0x7) << 5;
> > >> > > +}
> > >> > > +
> > >> > > +static void tx_rx(void *obj, void *data, QGuestAllocator *alloc)
> > >> > > +{
> > >> > > +    uint16_t value;
> > >> > > +    uint8_t integer, decimal;
> > >> > > +    QI2CDevice *i2cdev = (QI2CDevice *)obj;
> > >> > > +
> > >> > > +    /* Test default values */
> > >> > > +    value = qmp_sbtsi_get_temperature(TEST_ID);
> > >> > > +    g_assert_cmpuint(value, ==, 0);
> > >> > > +
> > >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
> > >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
> > >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 0);
> > >> > > +
> > >> > > +    /* Test setting temperature */
> > >> > > +    qmp_sbtsi_set_temperature(TEST_ID, 20000);
> > >> > > +    value = qmp_sbtsi_get_temperature(TEST_ID);
> > >> > > +    g_assert_cmpuint(value, ==, 20000);
> > >> > > +
> > >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
> > >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
> > >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 20000);
> > >> > > +
> > >> > > +    /* Set alert mask in config */
> > >> > > +    i2c_set8(i2cdev, REG_CONFIG_WR, CONFIG_ALERT_MASK);
> > >> > > +    value = i2c_get8(i2cdev, REG_CONFIG);
> > >> > > +    g_assert_cmphex(value, ==, CONFIG_ALERT_MASK);
> > >> > > +    /* Enable alarm_en */
> > >> > > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, ALARM_EN);
> > >> > > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
> > >> > > +    g_assert_cmphex(value, ==, ALARM_EN);
> > >> > > +
> > >> > > +    /* Test setting limits */
> > >> > > +    /* Limit low = 10.500 */
> > >> > > +    temp_to_regs(LIMIT_LOW, &integer, &decimal);
> > >> > > +    i2c_set8(i2cdev, REG_TEMP_LOW_INT, integer);
> > >> > > +    i2c_set8(i2cdev, REG_TEMP_LOW_DEC, decimal);
> > >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_LOW_INT);
> > >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_LOW_DEC);
> > >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==,
> LIMIT_LOW);
> > >> > > +    /* Limit high = 55.125 */
> > >> > > +    temp_to_regs(LIMIT_HIGH, &integer, &decimal);
> > >> > > +    i2c_set8(i2cdev, REG_TEMP_HIGH_INT, integer);
> > >> > > +    i2c_set8(i2cdev, REG_TEMP_HIGH_DEC, decimal);
> > >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_HIGH_INT);
> > >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_HIGH_DEC);
> > >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==,
> LIMIT_HIGH);
> > >> > > +    /* No alert is generated. */
> > >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> > >> > > +    g_assert_cmphex(value, ==, 0);
> > >> > > +
> > >> > > +    /* Test alert for low temperature */
> > >> > > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_LOW);
> > >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> > >> > > +    g_assert_cmphex(value, ==, STATUS_LOW_ALERT);
> > >> > > +
> > >> > > +    /* Test alert for high temperature */
> > >> > > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_HIGH);
> > >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> > >> > > +    g_assert_cmphex(value, ==, STATUS_HIGH_ALERT);
> > >> > > +
> > >> > > +    /* Disable alarm_en */
> > >> > > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, 0);
> > >> > > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
> > >> > > +    g_assert_cmphex(value, ==, 0);
> > >> > > +    /* No alert when alarm_en is false. */
> > >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> > >> > > +    g_assert_cmphex(value, ==, 0);
> > >> > > +}
> > >> > > +
> > >> > > +static void sbtsi_register_nodes(void)
> > >> > > +{
> > >> > > +    QOSGraphEdgeOptions opts = {
> > >> > > +        .extra_device_opts = "id=" TEST_ID ",address=0x4c"
> > >> > > +    };
> > >> > > +    add_qi2c_address(&opts, &(QI2CAddress) { TEST_ADDR });
> > >> > > +
> > >> > > +    qos_node_create_driver("sbtsi", i2c_device_create);
> > >> > > +    qos_node_consumes("sbtsi", "i2c-bus", &opts);
> > >> > > +
> > >> > > +    qos_add_test("tx-rx", "sbtsi", tx_rx, NULL);
> > >> > > +}
> > >> > > +libqos_init(sbtsi_register_nodes);
> > >> > > --
> > >> >
> > >> >
> > >> > + Corey for i2c maintainer.  The new sensor directory is mostly if
> not
> > >> > entirely i2c devices.  I didn't create a maintainer entry for this
> i2c
> > >> > device, but I can if desired and send out a v2.
> > >>
> > >> Yeah, I guess I should be maintainer there.  I'll queue up a change
> for
> > >> that.  Thanks.
> > >>
> > >> -corey
> > >>
> > >> >
> > >> >
> > >> > > 2.34.1.575.g55b058a8bb-goog
> > >> > >
> > >> > >
> > >>
> > >
>

Patrick Leis Jan. 27, 2022, 11:18 p.m. UTC | #12

On Thu, Jan 27, 2022 at 10:20 AM Hao Wu <[e-mail]> wrote:

>
> On Thu, Jan 27, 2022 at 6:55 AM Corey Minyard <[e-mail]> wrote:
>
>> On Wed, Jan 26, 2022 at 04:09:03PM -0800, Hao Wu wrote:
>> > Hi,
>> >
>> > Sorry for the late reply. I'm not sure what "auto-increment" means here.
>>
>> The question is: When a value is read, does the address automatically
>> increment.  I2C devices very often do this.  If you do a multi-byte
>> read, they often will read the value from address 0, then from address
>> 1, etc.  Same for writes.
>>
> The datasheet does not suggest such behavior could happen.
>
>>
>> > The kernel driver at
>> > https://lkml.org/lkml/2020/12/11/968
>> > only has byte-size read/write operations, so I don't see a problem here.
>> > The values are extracted
>> > from the datasheet.
>>
>> The *Linux* kernel driver my only do byte-size operations, but other
>> kernels may work different, and the Linux kernel may change.  You have
>> to implement from the datasheet, not the device driver.
>>
> The implementation is already according to the datasheet.
>
>> Thanks,
>>
>> -corey
>>
>>
I have to send out a new patchset to include my signature block since I'm
sending a patch Hao wrote.  Laurent pointed this out to me in a different
patch series.

From this exchange, I don't think there are other changes for v2.  Please
let me know if that's false.

Thanks,
Patrick


> >
>> > On Tue, Jan 18, 2022 at 9:10 AM Patrick Venture <[e-mail]>
>> wrote:
>> >
>> > >
>> > >
>> > > On Mon, Jan 17, 2022 at 6:05 AM Corey Minyard <[e-mail]>
>> wrote:
>> > >
>> > >> On Sun, Jan 09, 2022 at 06:17:34PM -0800, Patrick Venture wrote:
>> > >> > On Fri, Jan 7, 2022 at 7:04 PM Patrick Venture <[e-mail]
>> >
>> > >> wrote:
>> > >> >
>> > >> > > From: Hao Wu <[e-mail]>
>> > >> > >
>> > >> > > SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
>> > >> > > interface that reports AMD SoC's Ttcl (normalized temperature),
>> > >> > > and resembles a typical 8-pin remote temperature sensor's I2C
>> > >> interface
>> > >> > > to BMC.
>> > >> > >
>> > >> > > This patch implements a basic AMD SB-TSI sensor that is
>> > >> > > compatible with the open-source data sheet from AMD and Linux
>> > >> > > kernel driver.
>> > >> > >
>> > >> > > Reference:
>> > >> > > Linux kernel driver:
>> > >> > > https://lkml.org/lkml/2020/12/11/968
>> > >> > > Register Map:
>> > >> > > https://developer.amd.com/wp-content/resources/56255_3_03.PDF
>> > >> > > (Chapter 6)
>> > >> > >
>> > >> > > Signed-off-by: Hao Wu <[e-mail]>
>> > >> > > Reviewed-by: Doug Evans <[e-mail]>
>> > >> > > ---
>> > >> > >  hw/sensor/Kconfig            |   4 +
>> > >> > >  hw/sensor/meson.build        |   1 +
>> > >> > >  hw/sensor/tmp_sbtsi.c        | 393
>> > >> +++++++++++++++++++++++++++++++++++
>> > >> > >  hw/sensor/trace-events       |   5 +
>> > >> > >  hw/sensor/trace.h            |   1 +
>> > >> > >  meson.build                  |   1 +
>> > >> > >  tests/qtest/meson.build      |   1 +
>> > >> > >  tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++
>> > >> > >  8 files changed, 586 insertions(+)
>> > >> > >  create mode 100644 hw/sensor/tmp_sbtsi.c
>> > >> > >  create mode 100644 hw/sensor/trace-events
>> > >> > >  create mode 100644 hw/sensor/trace.h
>> > >> > >  create mode 100644 tests/qtest/tmp_sbtsi-test.c
>> > >> > >
>> > >> > > diff --git a/hw/sensor/Kconfig b/hw/sensor/Kconfig
>> > >> > > index 9c8a049b06..27f6f79c84 100644
>> > >> > > --- a/hw/sensor/Kconfig
>> > >> > > +++ b/hw/sensor/Kconfig
>> > >> > > @@ -21,3 +21,7 @@ config ADM1272
>> > >> > >  config MAX34451
>> > >> > >      bool
>> > >> > >      depends on I2C
>> > >> > > +
>> > >> > > +config AMDSBTSI
>> > >> > > +    bool
>> > >> > > +    depends on I2C
>> > >> > > diff --git a/hw/sensor/meson.build b/hw/sensor/meson.build
>> > >> > > index 059c4ca935..f7b0e645eb 100644
>> > >> > > --- a/hw/sensor/meson.build
>> > >> > > +++ b/hw/sensor/meson.build
>> > >> > > @@ -4,3 +4,4 @@ softmmu_ss.add(when: 'CONFIG_DPS310', if_true:
>> > >> > > files('dps310.c'))
>> > >> > >  softmmu_ss.add(when: 'CONFIG_EMC141X', if_true:
>> files('emc141x.c'))
>> > >> > >  softmmu_ss.add(when: 'CONFIG_ADM1272', if_true:
>> files('adm1272.c'))
>> > >> > >  softmmu_ss.add(when: 'CONFIG_MAX34451', if_true:
>> files('max34451.c'))
>> > >> > > +softmmu_ss.add(when: 'CONFIG_AMDSBTSI', if_true:
>> > >> files('tmp_sbtsi.c'))
>> > >> > > diff --git a/hw/sensor/tmp_sbtsi.c b/hw/sensor/tmp_sbtsi.c
>> > >> > > new file mode 100644
>> > >> > > index 0000000000..b68c7ebf61
>> > >> > > --- /dev/null
>> > >> > > +++ b/hw/sensor/tmp_sbtsi.c
>> > >> > > @@ -0,0 +1,393 @@
>> > >> > > +/*
>> > >> > > + * AMD SBI Temperature Sensor Interface (SB-TSI)
>> > >> > > + *
>> > >> > > + * Copyright 2021 Google LLC
>> > >> > > + *
>> > >> > > + * This program is free software; you can redistribute it and/or
>> > >> modify it
>> > >> > > + * under the terms of the GNU General Public License as
>> published by
>> > >> the
>> > >> > > + * Free Software Foundation; either version 2 of the License, or
>> > >> > > + * (at your option) any later version.
>> > >> > > + *
>> > >> > > + * This program is distributed in the hope that it will be
>> useful,
>> > >> but
>> > >> > > WITHOUT
>> > >> > > + * ANY WARRANTY; without even the implied warranty of
>> > >> MERCHANTABILITY or
>> > >> > > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
>> > >> License
>> > >> > > + * for more details.
>> > >> > > + */
>> > >> > > +
>> > >> > > +#include "qemu/osdep.h"
>> > >> > > +#include "hw/i2c/smbus_slave.h"
>> > >> > > +#include "hw/irq.h"
>> > >> > > +#include "migration/vmstate.h"
>> > >> > > +#include "qapi/error.h"
>> > >> > > +#include "qapi/visitor.h"
>> > >> > > +#include "qemu/log.h"
>> > >> > > +#include "qemu/module.h"
>> > >> > > +#include "trace.h"
>> > >> > > +
>> > >> > > +#define TYPE_SBTSI "sbtsi"
>> > >> > > +#define SBTSI(obj) OBJECT_CHECK(SBTSIState, (obj), TYPE_SBTSI)
>> > >> > > +
>> > >> > > +/**
>> > >> > > + * SBTSIState:
>> > >> > > + * temperatures are in units of 0.125 degrees
>> > >> > > + * @temperature: Temperature
>> > >> > > + * @limit_low: Lowest temperature
>> > >> > > + * @limit_high: Highest temperature
>> > >> > > + * @status: The status register
>> > >> > > + * @config: The config register
>> > >> > > + * @alert_config: The config for alarm_l output.
>> > >> > > + * @addr: The address to read/write for the next cmd.
>> > >> > > + * @alarm: The alarm_l output pin (GPIO)
>> > >> > > + */
>> > >> > > +typedef struct SBTSIState {
>> > >> > > +    SMBusDevice parent;
>> > >> > > +
>> > >> > > +    uint32_t temperature;
>> > >> > > +    uint32_t limit_low;
>> > >> > > +    uint32_t limit_high;
>> > >> > > +    uint8_t status;
>> > >> > > +    uint8_t config;
>> > >> > > +    uint8_t alert_config;
>> > >> > > +    uint8_t addr;
>> > >> > > +    qemu_irq alarm;
>> > >> > > +} SBTSIState;
>> > >> > > +
>> > >> > > +/*
>> > >> > > + * SB-TSI registers only support SMBus byte data access. "_INT"
>> > >> registers
>> > >> > > are
>> > >> > > + * the integer part of a temperature value or limit, and "_DEC"
>> > >> registers
>> > >> > > are
>> > >> > > + * corresponding decimal parts.
>> > >> > > + */
>> > >> > > +#define SBTSI_REG_TEMP_INT      0x01 /* RO */
>> > >> > > +#define SBTSI_REG_STATUS        0x02 /* RO */
>> > >> > > +#define SBTSI_REG_CONFIG        0x03 /* RO */
>> > >> > > +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */
>> > >> > > +#define SBTSI_REG_TEMP_LOW_INT  0x08 /* RW */
>> > >> > > +#define SBTSI_REG_CONFIG_WR     0x09 /* RW */
>> > >> > > +#define SBTSI_REG_TEMP_DEC      0x10 /* RO */
>> > >> > > +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */
>> > >> > > +#define SBTSI_REG_TEMP_LOW_DEC  0x14 /* RW */
>> > >> > > +#define SBTSI_REG_ALERT_CONFIG  0xBF /* RW */
>> > >> > > +#define SBTSI_REG_MAN           0xFE /* RO */
>> > >> > > +#define SBTSI_REG_REV           0xFF /* RO */
>> > >> > > +
>> > >> > > +#define SBTSI_STATUS_HIGH_ALERT BIT(4)
>> > >> > > +#define SBTSI_STATUS_LOW_ALERT  BIT(3)
>> > >> > > +#define SBTSI_CONFIG_ALERT_MASK BIT(7)
>> > >> > > +#define SBTSI_ALARM_EN          BIT(0)
>> > >> > > +
>> > >> > > +#define SBTSI_LIMIT_LOW_DEFAULT (0)
>> > >> > > +#define SBTSI_LIMIT_HIGH_DEFAULT (560)
>> > >> > > +#define SBTSI_MAN_DEFAULT (0)
>> > >> > > +#define SBTSI_REV_DEFAULT (4)
>> > >> > > +#define SBTSI_ALARM_L "alarm_l"
>> > >> > > +
>> > >> > > +/* The temperature we stored are in units of 0.125 degrees. */
>> > >> > > +#define SBTSI_TEMP_UNIT_IN_MILLIDEGREE 125
>> > >> > > +
>> > >> > > +/*
>> > >> > > + * The integer part and decimal of the temperature both 8 bits.
>> > >> > > + * Only the top 3 bits of the decimal parts are used.
>> > >> > > + * So the max temperature is (2^8-1) + (2^3-1)/8 = 255.875
>> degrees.
>> > >> > > + */
>> > >> > > +#define SBTSI_TEMP_MAX 255875
>> > >> > > +
>> > >> > > +/* The integer part of the temperature in terms of 0.125
>> degrees. */
>> > >> > > +static uint8_t get_temp_int(uint32_t temp)
>> > >> > > +{
>> > >> > > +    return temp >> 3;
>> > >> > > +}
>> > >> > > +
>> > >> > > +/*
>> > >> > > + * The decimal part of the temperature, in terms of 0.125
>> degrees.
>> > >> > > + * H/W store it in the top 3 bits so we shift it by 5.
>> > >> > > + */
>> > >> > > +static uint8_t get_temp_dec(uint32_t temp)
>> > >> > > +{
>> > >> > > +    return (temp & 0x7) << 5;
>> > >> > > +}
>> > >> > > +
>> > >> > > +/*
>> > >> > > + * Compute the temperature using the integer and decimal part,
>> > >> > > + * in terms of 0.125 degrees. The decimal part are only the top
>> 3
>> > >> bits
>> > >> > > + * so we shift it by 5 here.
>> > >> > > + */
>> > >> > > +static uint32_t compute_temp(uint8_t integer, uint8_t decimal)
>> > >> > > +{
>> > >> > > +    return (integer << 3) + (decimal >> 5);
>> > >> > > +}
>> > >> > > +
>> > >> > > +/* Compute new temp with new int part of the temperature. */
>> > >> > > +static uint32_t compute_temp_int(uint32_t temp, uint8_t integer)
>> > >> > > +{
>> > >> > > +    return compute_temp(integer, get_temp_dec(temp));
>> > >> > > +}
>> > >> > > +
>> > >> > > +/* Compute new temp with new dec part of the temperature. */
>> > >> > > +static uint32_t compute_temp_dec(uint32_t temp, uint8_t decimal)
>> > >> > > +{
>> > >> > > +    return compute_temp(get_temp_int(temp), decimal);
>> > >> > > +}
>> > >> > > +
>> > >> > > +/* The integer part of the temperature. */
>> > >> > > +static void sbtsi_update_status(SBTSIState *s)
>> > >> > > +{
>> > >> > > +    s->status = 0;
>> > >> > > +    if (s->alert_config & SBTSI_ALARM_EN) {
>> > >> > > +        if (s->temperature >= s->limit_high) {
>> > >> > > +            s->status |= SBTSI_STATUS_HIGH_ALERT;
>> > >> > > +        }
>> > >> > > +        if (s->temperature <= s->limit_low) {
>> > >> > > +            s->status |= SBTSI_STATUS_LOW_ALERT;
>> > >> > > +        }
>> > >> > > +    }
>> > >> > > +}
>> > >> > > +
>> > >> > > +static void sbtsi_update_alarm(SBTSIState *s)
>> > >> > > +{
>> > >> > > +    sbtsi_update_status(s);
>> > >> > > +    if (s->status != 0 && !(s->config &
>> SBTSI_CONFIG_ALERT_MASK)) {
>> > >> > > +        qemu_irq_raise(s->alarm);
>> > >> > > +    } else {
>> > >> > > +        qemu_irq_lower(s->alarm);
>> > >> > > +    }
>> > >> > > +}
>> > >> > > +
>> > >> > > +static uint8_t sbtsi_read_byte(SMBusDevice *d)
>> > >> > > +{
>> > >> > > +    SBTSIState *s = SBTSI(d);
>> > >> > > +    uint8_t data = 0;
>> > >> > > +
>> > >> > > +    switch (s->addr) {
>> > >> > > +    case SBTSI_REG_TEMP_INT:
>> > >> > > +        data = get_temp_int(s->temperature);
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_TEMP_DEC:
>> > >> > > +        data = get_temp_dec(s->temperature);
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_TEMP_HIGH_INT:
>> > >> > > +        data = get_temp_int(s->limit_high);
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_TEMP_LOW_INT:
>> > >> > > +        data = get_temp_int(s->limit_low);
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_TEMP_HIGH_DEC:
>> > >> > > +        data = get_temp_dec(s->limit_high);
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_TEMP_LOW_DEC:
>> > >> > > +        data = get_temp_dec(s->limit_low);
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_CONFIG:
>> > >> > > +    case SBTSI_REG_CONFIG_WR:
>> > >> > > +        data = s->config;
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_STATUS:
>> > >> > > +        sbtsi_update_alarm(s);
>> > >> > > +        data = s->status;
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_ALERT_CONFIG:
>> > >> > > +        data = s->alert_config;
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_MAN:
>> > >> > > +        data = SBTSI_MAN_DEFAULT;
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_REV:
>> > >> > > +        data = SBTSI_REV_DEFAULT;
>> > >> > > +        break;
>> > >>
>> > >> Does this device do some sort of auto-increment on the address when
>> > >> reading/writing?
>> > >>
>> > >
>> > > +Hao Wu <[e-mail]>   - Please take a look at the above
>> > > question.  I imagine it's a while since you've thought about it, but
>> please
>> > > double check :)
>> > > Thanks!
>> > >
>> > >
>> > >> Other than that possible issue, I don't see anything else, it's
>> pretty
>> > >> straightforward.
>> > >>
>> > >> > > +
>> > >> > > +    default:
>> > >> > > +        qemu_log_mask(LOG_GUEST_ERROR,
>> > >> > > +                "%s: reading from invalid reg: 0x%02x\n",
>> > >> > > +                __func__, s->addr);
>> > >> > > +        break;
>> > >> > > +    }
>> > >> > > +
>> > >> > > +    trace_tmp_sbtsi_read_data(s->addr, data);
>> > >> > > +    return data;
>> > >> > > +}
>> > >> > > +
>> > >> > > +static void sbtsi_write(SBTSIState *s, uint8_t data)
>> > >> > > +{
>> > >> > > +    trace_tmp_sbtsi_write_data(s->addr, data);
>> > >> > > +    switch (s->addr) {
>> > >> > > +    case SBTSI_REG_CONFIG_WR:
>> > >> > > +        s->config = data;
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_TEMP_HIGH_INT:
>> > >> > > +        s->limit_high = compute_temp_int(s->limit_high, data);
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_TEMP_LOW_INT:
>> > >> > > +        s->limit_low = compute_temp_int(s->limit_low, data);
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_TEMP_HIGH_DEC:
>> > >> > > +        s->limit_high = compute_temp_dec(s->limit_high, data);
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_TEMP_LOW_DEC:
>> > >> > > +        s->limit_low = compute_temp_dec(s->limit_low, data);
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_ALERT_CONFIG:
>> > >> > > +        s->alert_config = data;
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    case SBTSI_REG_TEMP_INT:
>> > >> > > +    case SBTSI_REG_TEMP_DEC:
>> > >> > > +    case SBTSI_REG_CONFIG:
>> > >> > > +    case SBTSI_REG_STATUS:
>> > >> > > +    case SBTSI_REG_MAN:
>> > >> > > +    case SBTSI_REG_REV:
>> > >> > > +        qemu_log_mask(LOG_GUEST_ERROR,
>> > >> > > +                "%s: writing to read only reg: 0x%02x data:
>> > >> 0x%02x\n",
>> > >> > > +                __func__, s->addr, data);
>> > >> > > +        break;
>> > >> > > +
>> > >> > > +    default:
>> > >> > > +        qemu_log_mask(LOG_GUEST_ERROR,
>> > >> > > +                "%s: writing to invalid reg: 0x%02x data:
>> 0x%02x\n",
>> > >> > > +                __func__, s->addr, data);
>> > >> > > +        break;
>> > >> > > +    }
>> > >> > > +    sbtsi_update_alarm(s);
>> > >> > > +}
>> > >> > > +
>> > >> > > +static int sbtsi_write_data(SMBusDevice *d, uint8_t *buf,
>> uint8_t
>> > >> len)
>> > >> > > +{
>> > >> > > +    SBTSIState *s = SBTSI(d);
>> > >> > > +
>> > >> > > +    if (len == 0) {
>> > >> > > +        qemu_log_mask(LOG_GUEST_ERROR, "%s: writing empty
>> data\n",
>> > >> > > __func__);
>> > >> > > +        return -1;
>> > >> > > +    }
>> > >> > > +
>> > >> > > +    s->addr = buf[0];
>> > >> > > +    if (len > 1) {
>> > >> > > +        sbtsi_write(s, buf[1]);
>> > >> > > +        if (len > 2) {
>> > >> > > +            qemu_log_mask(LOG_GUEST_ERROR, "%s: extra data at
>> end\n",
>> > >> > > __func__);
>> > >> > > +        }
>> > >> > > +    }
>> > >> > > +    return 0;
>> > >> > > +}
>> > >> > > +
>> > >> > > +/* Units are millidegrees. */
>> > >> > > +static void sbtsi_get_temperature(Object *obj, Visitor *v,
>> const char
>> > >> > > *name,
>> > >> > > +                                  void *opaque, Error **errp)
>> > >> > > +{
>> > >> > > +    SBTSIState *s = SBTSI(obj);
>> > >> > > +    uint32_t temp = s->temperature *
>> SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
>> > >> > > +
>> > >> > > +    visit_type_uint32(v, name, &temp, errp);
>> > >> > > +}
>> > >> > > +
>> > >> > > +/* Units are millidegrees. */
>> > >> > > +static void sbtsi_set_temperature(Object *obj, Visitor *v,
>> const char
>> > >> > > *name,
>> > >> > > +                                  void *opaque, Error **errp)
>> > >> > > +{
>> > >> > > +    SBTSIState *s = SBTSI(obj);
>> > >> > > +    uint32_t temp;
>> > >> > > +
>> > >> > > +    if (!visit_type_uint32(v, name, &temp, errp)) {
>> > >> > > +        return;
>> > >> > > +    }
>> > >> > > +    if (temp > SBTSI_TEMP_MAX) {
>> > >> > > +        error_setg(errp, "value %" PRIu32 ".%03" PRIu32 " C is
>> out of
>> > >> > > range",
>> > >> > > +                   temp / 1000, temp % 1000);
>> > >> > > +        return;
>> > >> > > +    }
>> > >> > > +
>> > >> > > +    s->temperature = temp / SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
>> > >> > > +    sbtsi_update_alarm(s);
>> > >> > > +}
>> > >> > > +
>> > >> > > +static int sbtsi_post_load(void *opaque, int version_id)
>> > >> > > +{
>> > >> > > +    SBTSIState *s = opaque;
>> > >> > > +
>> > >> > > +    sbtsi_update_alarm(s);
>> > >> > > +    return 0;
>> > >> > > +}
>> > >> > > +
>> > >> > > +static const VMStateDescription vmstate_sbtsi = {
>> > >> > > +    .name = "SBTSI",
>> > >> > > +    .version_id = 0,
>> > >> > > +    .minimum_version_id = 0,
>> > >> > > +    .post_load = sbtsi_post_load,
>> > >> > > +    .fields = (VMStateField[]) {
>> > >> > > +        VMSTATE_UINT32(temperature, SBTSIState),
>> > >> > > +        VMSTATE_UINT32(limit_low, SBTSIState),
>> > >> > > +        VMSTATE_UINT32(limit_high, SBTSIState),
>> > >> > > +        VMSTATE_UINT8(config, SBTSIState),
>> > >> > > +        VMSTATE_UINT8(status, SBTSIState),
>> > >> > > +        VMSTATE_UINT8(addr, SBTSIState),
>> > >> > > +        VMSTATE_END_OF_LIST()
>> > >> > > +    }
>> > >> > > +};
>> > >> > > +
>> > >> > > +static void sbtsi_enter_reset(Object *obj, ResetType type)
>> > >> > > +{
>> > >> > > +    SBTSIState *s = SBTSI(obj);
>> > >> > > +
>> > >> > > +    s->config = 0;
>> > >> > > +    s->limit_low = SBTSI_LIMIT_LOW_DEFAULT;
>> > >> > > +    s->limit_high = SBTSI_LIMIT_HIGH_DEFAULT;
>> > >> > > +}
>> > >> > > +
>> > >> > > +static void sbtsi_hold_reset(Object *obj)
>> > >> > > +{
>> > >> > > +    SBTSIState *s = SBTSI(obj);
>> > >> > > +
>> > >> > > +    qemu_irq_lower(s->alarm);
>> > >> > > +}
>> > >> > > +
>> > >> > > +static void sbtsi_init(Object *obj)
>> > >> > > +{
>> > >> > > +    SBTSIState *s = SBTSI(obj);
>> > >> > > +
>> > >> > > +    /* Current temperature in millidegrees. */
>> > >> > > +    object_property_add(obj, "temperature", "uint32",
>> > >> > > +                        sbtsi_get_temperature,
>> sbtsi_set_temperature,
>> > >> > > +                        NULL, NULL);
>> > >> > > +    qdev_init_gpio_out_named(DEVICE(obj), &s->alarm,
>> SBTSI_ALARM_L,
>> > >> 0);
>> > >> > > +}
>> > >> > > +
>> > >> > > +static void sbtsi_class_init(ObjectClass *klass, void *data)
>> > >> > > +{
>> > >> > > +    ResettableClass *rc = RESETTABLE_CLASS(klass);
>> > >> > > +    DeviceClass *dc = DEVICE_CLASS(klass);
>> > >> > > +    SMBusDeviceClass *k = SMBUS_DEVICE_CLASS(klass);
>> > >> > > +
>> > >> > > +    dc->desc = "SB-TSI Temperature Sensor";
>> > >> > > +    dc->vmsd = &vmstate_sbtsi;
>> > >> > > +    k->write_data = sbtsi_write_data;
>> > >> > > +    k->receive_byte = sbtsi_read_byte;
>> > >> > > +    rc->phases.enter = sbtsi_enter_reset;
>> > >> > > +    rc->phases.hold = sbtsi_hold_reset;
>> > >> > > +}
>> > >> > > +
>> > >> > > +static const TypeInfo sbtsi_info = {
>> > >> > > +    .name          = TYPE_SBTSI,
>> > >> > > +    .parent        = TYPE_SMBUS_DEVICE,
>> > >> > > +    .instance_size = sizeof(SBTSIState),
>> > >> > > +    .instance_init = sbtsi_init,
>> > >> > > +    .class_init    = sbtsi_class_init,
>> > >> > > +};
>> > >> > > +
>> > >> > > +static void sbtsi_register_types(void)
>> > >> > > +{
>> > >> > > +    type_register_static(&sbtsi_info);
>> > >> > > +}
>> > >> > > +
>> > >> > > +type_init(sbtsi_register_types)
>> > >> > > diff --git a/hw/sensor/trace-events b/hw/sensor/trace-events
>> > >> > > new file mode 100644
>> > >> > > index 0000000000..21ab3809e2
>> > >> > > --- /dev/null
>> > >> > > +++ b/hw/sensor/trace-events
>> > >> > > @@ -0,0 +1,5 @@
>> > >> > > +# See docs/devel/tracing.rst for syntax documentation.
>> > >> > > +
>> > >> > > +# tmp_sbtsi.c
>> > >> > > +tmp_sbtsi_write_data(uint8_t addr, uint8_t value) "SBTSI write
>> > >> > > addr:0x%02x data: 0x%02x"
>> > >> > > +tmp_sbtsi_read_data(uint8_t addr, uint8_t value) "SBTSI read
>> > >> addr:0x%02x
>> > >> > > data: 0x%02x"
>> > >> > > diff --git a/hw/sensor/trace.h b/hw/sensor/trace.h
>> > >> > > new file mode 100644
>> > >> > > index 0000000000..e4721560b0
>> > >> > > --- /dev/null
>> > >> > > +++ b/hw/sensor/trace.h
>> > >> > > @@ -0,0 +1 @@
>> > >> > > +#include "trace/trace-hw_sensor.h"
>> > >> > > diff --git a/meson.build b/meson.build
>> > >> > > index 53065e96ec..f8ab0bf74e 100644
>> > >> > > --- a/meson.build
>> > >> > > +++ b/meson.build
>> > >> > > @@ -2494,6 +2494,7 @@ if have_system
>> > >> > >      'hw/rtc',
>> > >> > >      'hw/s390x',
>> > >> > >      'hw/scsi',
>> > >> > > +    'hw/sensor',
>> > >> > >      'hw/sd',
>> > >> > >      'hw/sh4',
>> > >> > >      'hw/sparc',
>> > >> > > diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
>> > >> > > index 37e1eaa449..d1a8c38f74 100644
>> > >> > > --- a/tests/qtest/meson.build
>> > >> > > +++ b/tests/qtest/meson.build
>> > >> > > @@ -254,6 +254,7 @@ qos_test_ss.add(
>> > >> > >    'spapr-phb-test.c',
>> > >> > >    'tmp105-test.c',
>> > >> > >    'emc141x-test.c',
>> > >> > > +  'tmp_sbtsi-test.c',
>> > >> > >    'usb-hcd-ohci-test.c',
>> > >> > >    'virtio-test.c',
>> > >> > >    'virtio-blk-test.c',
>> > >> > > diff --git a/tests/qtest/tmp_sbtsi-test.c
>> > >> b/tests/qtest/tmp_sbtsi-test.c
>> > >> > > new file mode 100644
>> > >> > > index 0000000000..7f5fafacc7
>> > >> > > --- /dev/null
>> > >> > > +++ b/tests/qtest/tmp_sbtsi-test.c
>> > >> > > @@ -0,0 +1,180 @@
>> > >> > > +/*
>> > >> > > + * QTests for the SBTSI temperature sensor
>> > >> > > + *
>> > >> > > + * Copyright 2020 Google LLC
>> > >> > > + *
>> > >> > > + * This program is free software; you can redistribute it and/or
>> > >> modify it
>> > >> > > + * under the terms of the GNU General Public License as
>> published by
>> > >> the
>> > >> > > + * Free Software Foundation; either version 2 of the License, or
>> > >> > > + * (at your option) any later version.
>> > >> > > + *
>> > >> > > + * This program is distributed in the hope that it will be
>> useful,
>> > >> but
>> > >> > > WITHOUT
>> > >> > > + * ANY WARRANTY; without even the implied warranty of
>> > >> MERCHANTABILITY or
>> > >> > > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
>> > >> License
>> > >> > > + * for more details.
>> > >> > > + */
>> > >> > > +
>> > >> > > +#include "qemu/osdep.h"
>> > >> > > +
>> > >> > > +#include "libqtest-single.h"
>> > >> > > +#include "libqos/qgraph.h"
>> > >> > > +#include "libqos/i2c.h"
>> > >> > > +#include "qapi/qmp/qdict.h"
>> > >> > > +#include "qemu/bitops.h"
>> > >> > > +
>> > >> > > +#define TEST_ID   "sbtsi-test"
>> > >> > > +#define TEST_ADDR (0x4c)
>> > >> > > +
>> > >> > > +/*
>> > >> > > + * SB-TSI registers only support SMBus byte data access. "_INT"
>> > >> registers
>> > >> > > are
>> > >> > > + * the integer part of a temperature value or limit, and "_DEC"
>> > >> registers
>> > >> > > are
>> > >> > > + * corresponding decimal parts.
>> > >> > > + */
>> > >> > > +#define REG_TEMP_INT      0x01 /* RO */
>> > >> > > +#define REG_STATUS        0x02 /* RO */
>> > >> > > +#define REG_CONFIG        0x03 /* RO */
>> > >> > > +#define REG_TEMP_HIGH_INT 0x07 /* RW */
>> > >> > > +#define REG_TEMP_LOW_INT  0x08 /* RW */
>> > >> > > +#define REG_CONFIG_WR     0x09 /* RW */
>> > >> > > +#define REG_TEMP_DEC      0x10 /* RO */
>> > >> > > +#define REG_TEMP_HIGH_DEC 0x13 /* RW */
>> > >> > > +#define REG_TEMP_LOW_DEC  0x14 /* RW */
>> > >> > > +#define REG_ALERT_CONFIG  0xBF /* RW */
>> > >> > > +
>> > >> > > +#define STATUS_HIGH_ALERT BIT(4)
>> > >> > > +#define STATUS_LOW_ALERT  BIT(3)
>> > >> > > +#define CONFIG_ALERT_MASK BIT(7)
>> > >> > > +#define ALARM_EN          BIT(0)
>> > >> > > +
>> > >> > > +/* The temperature stored are in units of 0.125 degrees. */
>> > >> > > +#define TEMP_UNIT_IN_MILLIDEGREE 125
>> > >> > > +#define LIMIT_LOW (10500)
>> > >> > > +#define LIMIT_HIGH (55125)
>> > >> > > +
>> > >> > > +static uint32_t qmp_sbtsi_get_temperature(const char *id)
>> > >> > > +{
>> > >> > > +    QDict *response;
>> > >> > > +    int ret;
>> > >> > > +
>> > >> > > +    response = qmp("{ 'execute': 'qom-get', 'arguments': {
>> 'path':
>> > >> %s, "
>> > >> > > +                   "'property': 'temperature' } }", id);
>> > >> > > +    g_assert(qdict_haskey(response, "return"));
>> > >> > > +    ret = (uint32_t)qdict_get_int(response, "return");
>> > >> > > +    qobject_unref(response);
>> > >> > > +    return ret;
>> > >> > > +}
>> > >> > > +
>> > >> > > +static void qmp_sbtsi_set_temperature(const char *id, uint32_t
>> value)
>> > >> > > +{
>> > >> > > +    QDict *response;
>> > >> > > +
>> > >> > > +    response = qmp("{ 'execute': 'qom-set', 'arguments': {
>> 'path':
>> > >> %s, "
>> > >> > > +                   "'property': 'temperature', 'value': %d }
>> }", id,
>> > >> > > value);
>> > >> > > +    g_assert(qdict_haskey(response, "return"));
>> > >> > > +    qobject_unref(response);
>> > >> > > +}
>> > >> > > +
>> > >> > > +/*
>> > >> > > + * Compute the temperature using the integer and decimal part
>> and
>> > >> return
>> > >> > > + * millidegrees. The decimal part are only the top 3 bits so we
>> > >> shift it
>> > >> > > by
>> > >> > > + * 5 here.
>> > >> > > + */
>> > >> > > +static uint32_t regs_to_temp(uint8_t integer, uint8_t decimal)
>> > >> > > +{
>> > >> > > +    return ((integer << 3) + (decimal >> 5)) *
>> > >> TEMP_UNIT_IN_MILLIDEGREE;
>> > >> > > +}
>> > >> > > +
>> > >> > > +/*
>> > >> > > + * Compute the integer and decimal parts of the temperature in
>> > >> > > millidegrees.
>> > >> > > + * H/W store the decimal in the top 3 bits so we shift it by 5.
>> > >> > > + */
>> > >> > > +static void temp_to_regs(uint32_t temp, uint8_t *integer,
>> uint8_t
>> > >> > > *decimal)
>> > >> > > +{
>> > >> > > +    temp /= TEMP_UNIT_IN_MILLIDEGREE;
>> > >> > > +    *integer = temp >> 3;
>> > >> > > +    *decimal = (temp & 0x7) << 5;
>> > >> > > +}
>> > >> > > +
>> > >> > > +static void tx_rx(void *obj, void *data, QGuestAllocator *alloc)
>> > >> > > +{
>> > >> > > +    uint16_t value;
>> > >> > > +    uint8_t integer, decimal;
>> > >> > > +    QI2CDevice *i2cdev = (QI2CDevice *)obj;
>> > >> > > +
>> > >> > > +    /* Test default values */
>> > >> > > +    value = qmp_sbtsi_get_temperature(TEST_ID);
>> > >> > > +    g_assert_cmpuint(value, ==, 0);
>> > >> > > +
>> > >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
>> > >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
>> > >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 0);
>> > >> > > +
>> > >> > > +    /* Test setting temperature */
>> > >> > > +    qmp_sbtsi_set_temperature(TEST_ID, 20000);
>> > >> > > +    value = qmp_sbtsi_get_temperature(TEST_ID);
>> > >> > > +    g_assert_cmpuint(value, ==, 20000);
>> > >> > > +
>> > >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
>> > >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
>> > >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 20000);
>> > >> > > +
>> > >> > > +    /* Set alert mask in config */
>> > >> > > +    i2c_set8(i2cdev, REG_CONFIG_WR, CONFIG_ALERT_MASK);
>> > >> > > +    value = i2c_get8(i2cdev, REG_CONFIG);
>> > >> > > +    g_assert_cmphex(value, ==, CONFIG_ALERT_MASK);
>> > >> > > +    /* Enable alarm_en */
>> > >> > > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, ALARM_EN);
>> > >> > > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
>> > >> > > +    g_assert_cmphex(value, ==, ALARM_EN);
>> > >> > > +
>> > >> > > +    /* Test setting limits */
>> > >> > > +    /* Limit low = 10.500 */
>> > >> > > +    temp_to_regs(LIMIT_LOW, &integer, &decimal);
>> > >> > > +    i2c_set8(i2cdev, REG_TEMP_LOW_INT, integer);
>> > >> > > +    i2c_set8(i2cdev, REG_TEMP_LOW_DEC, decimal);
>> > >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_LOW_INT);
>> > >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_LOW_DEC);
>> > >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==,
>> LIMIT_LOW);
>> > >> > > +    /* Limit high = 55.125 */
>> > >> > > +    temp_to_regs(LIMIT_HIGH, &integer, &decimal);
>> > >> > > +    i2c_set8(i2cdev, REG_TEMP_HIGH_INT, integer);
>> > >> > > +    i2c_set8(i2cdev, REG_TEMP_HIGH_DEC, decimal);
>> > >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_HIGH_INT);
>> > >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_HIGH_DEC);
>> > >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==,
>> LIMIT_HIGH);
>> > >> > > +    /* No alert is generated. */
>> > >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
>> > >> > > +    g_assert_cmphex(value, ==, 0);
>> > >> > > +
>> > >> > > +    /* Test alert for low temperature */
>> > >> > > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_LOW);
>> > >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
>> > >> > > +    g_assert_cmphex(value, ==, STATUS_LOW_ALERT);
>> > >> > > +
>> > >> > > +    /* Test alert for high temperature */
>> > >> > > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_HIGH);
>> > >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
>> > >> > > +    g_assert_cmphex(value, ==, STATUS_HIGH_ALERT);
>> > >> > > +
>> > >> > > +    /* Disable alarm_en */
>> > >> > > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, 0);
>> > >> > > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
>> > >> > > +    g_assert_cmphex(value, ==, 0);
>> > >> > > +    /* No alert when alarm_en is false. */
>> > >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
>> > >> > > +    g_assert_cmphex(value, ==, 0);
>> > >> > > +}
>> > >> > > +
>> > >> > > +static void sbtsi_register_nodes(void)
>> > >> > > +{
>> > >> > > +    QOSGraphEdgeOptions opts = {
>> > >> > > +        .extra_device_opts = "id=" TEST_ID ",address=0x4c"
>> > >> > > +    };
>> > >> > > +    add_qi2c_address(&opts, &(QI2CAddress) { TEST_ADDR });
>> > >> > > +
>> > >> > > +    qos_node_create_driver("sbtsi", i2c_device_create);
>> > >> > > +    qos_node_consumes("sbtsi", "i2c-bus", &opts);
>> > >> > > +
>> > >> > > +    qos_add_test("tx-rx", "sbtsi", tx_rx, NULL);
>> > >> > > +}
>> > >> > > +libqos_init(sbtsi_register_nodes);
>> > >> > > --
>> > >> >
>> > >> >
>> > >> > + Corey for i2c maintainer.  The new sensor directory is mostly if
>> not
>> > >> > entirely i2c devices.  I didn't create a maintainer entry for this
>> i2c
>> > >> > device, but I can if desired and send out a v2.
>> > >>
>> > >> Yeah, I guess I should be maintainer there.  I'll queue up a change
>> for
>> > >> that.  Thanks.
>> > >>
>> > >> -corey
>> > >>
>> > >> >
>> > >> >
>> > >> > > 2.34.1.575.g55b058a8bb-goog
>> > >> > >
>> > >> > >
>> > >>
>> > >
>>
>

Corey Minyard Jan. 28, 2022, 1:58 a.m. UTC | #13

On Thu, Jan 27, 2022 at 03:18:43PM -0800, Patrick Venture wrote:
> On Thu, Jan 27, 2022 at 10:20 AM Hao Wu <[e-mail]> wrote:
> 
> >
> > On Thu, Jan 27, 2022 at 6:55 AM Corey Minyard <[e-mail]> wrote:
> >
> >> On Wed, Jan 26, 2022 at 04:09:03PM -0800, Hao Wu wrote:
> >> > Hi,
> >> >
> >> > Sorry for the late reply. I'm not sure what "auto-increment" means here.
> >>
> >> The question is: When a value is read, does the address automatically
> >> increment.  I2C devices very often do this.  If you do a multi-byte
> >> read, they often will read the value from address 0, then from address
> >> 1, etc.  Same for writes.
> >>
> > The datasheet does not suggest such behavior could happen.
> >
> >>
> >> > The kernel driver at
> >> > https://lkml.org/lkml/2020/12/11/968
> >> > only has byte-size read/write operations, so I don't see a problem here.
> >> > The values are extracted
> >> > from the datasheet.
> >>
> >> The *Linux* kernel driver my only do byte-size operations, but other
> >> kernels may work different, and the Linux kernel may change.  You have
> >> to implement from the datasheet, not the device driver.
> >>
> > The implementation is already according to the datasheet.
> >
> >> Thanks,
> >>
> >> -corey
> >>
> >>
> I have to send out a new patchset to include my signature block since I'm
> sending a patch Hao wrote.  Laurent pointed this out to me in a different
> patch series.
> 
> From this exchange, I don't think there are other changes for v2.  Please
> let me know if that's false.

Yes, we are good.  It's a little surprising, hopefully we don't have to
fix it in the future if it works that way the datasheet didn't say so.

Acked-by: Corey Minyard <[e-mail]>

> 
> Thanks,
> Patrick
> 
> 
> > >
> >> > On Tue, Jan 18, 2022 at 9:10 AM Patrick Venture <[e-mail]>
> >> wrote:
> >> >
> >> > >
> >> > >
> >> > > On Mon, Jan 17, 2022 at 6:05 AM Corey Minyard <[e-mail]>
> >> wrote:
> >> > >
> >> > >> On Sun, Jan 09, 2022 at 06:17:34PM -0800, Patrick Venture wrote:
> >> > >> > On Fri, Jan 7, 2022 at 7:04 PM Patrick Venture <[e-mail]
> >> >
> >> > >> wrote:
> >> > >> >
> >> > >> > > From: Hao Wu <[e-mail]>
> >> > >> > >
> >> > >> > > SB Temperature Sensor Interface (SB-TSI) is an SMBus compatible
> >> > >> > > interface that reports AMD SoC's Ttcl (normalized temperature),
> >> > >> > > and resembles a typical 8-pin remote temperature sensor's I2C
> >> > >> interface
> >> > >> > > to BMC.
> >> > >> > >
> >> > >> > > This patch implements a basic AMD SB-TSI sensor that is
> >> > >> > > compatible with the open-source data sheet from AMD and Linux
> >> > >> > > kernel driver.
> >> > >> > >
> >> > >> > > Reference:
> >> > >> > > Linux kernel driver:
> >> > >> > > https://lkml.org/lkml/2020/12/11/968
> >> > >> > > Register Map:
> >> > >> > > https://developer.amd.com/wp-content/resources/56255_3_03.PDF
> >> > >> > > (Chapter 6)
> >> > >> > >
> >> > >> > > Signed-off-by: Hao Wu <[e-mail]>
> >> > >> > > Reviewed-by: Doug Evans <[e-mail]>
> >> > >> > > ---
> >> > >> > >  hw/sensor/Kconfig            |   4 +
> >> > >> > >  hw/sensor/meson.build        |   1 +
> >> > >> > >  hw/sensor/tmp_sbtsi.c        | 393
> >> > >> +++++++++++++++++++++++++++++++++++
> >> > >> > >  hw/sensor/trace-events       |   5 +
> >> > >> > >  hw/sensor/trace.h            |   1 +
> >> > >> > >  meson.build                  |   1 +
> >> > >> > >  tests/qtest/meson.build      |   1 +
> >> > >> > >  tests/qtest/tmp_sbtsi-test.c | 180 ++++++++++++++++
> >> > >> > >  8 files changed, 586 insertions(+)
> >> > >> > >  create mode 100644 hw/sensor/tmp_sbtsi.c
> >> > >> > >  create mode 100644 hw/sensor/trace-events
> >> > >> > >  create mode 100644 hw/sensor/trace.h
> >> > >> > >  create mode 100644 tests/qtest/tmp_sbtsi-test.c
> >> > >> > >
> >> > >> > > diff --git a/hw/sensor/Kconfig b/hw/sensor/Kconfig
> >> > >> > > index 9c8a049b06..27f6f79c84 100644
> >> > >> > > --- a/hw/sensor/Kconfig
> >> > >> > > +++ b/hw/sensor/Kconfig
> >> > >> > > @@ -21,3 +21,7 @@ config ADM1272
> >> > >> > >  config MAX34451
> >> > >> > >      bool
> >> > >> > >      depends on I2C
> >> > >> > > +
> >> > >> > > +config AMDSBTSI
> >> > >> > > +    bool
> >> > >> > > +    depends on I2C
> >> > >> > > diff --git a/hw/sensor/meson.build b/hw/sensor/meson.build
> >> > >> > > index 059c4ca935..f7b0e645eb 100644
> >> > >> > > --- a/hw/sensor/meson.build
> >> > >> > > +++ b/hw/sensor/meson.build
> >> > >> > > @@ -4,3 +4,4 @@ softmmu_ss.add(when: 'CONFIG_DPS310', if_true:
> >> > >> > > files('dps310.c'))
> >> > >> > >  softmmu_ss.add(when: 'CONFIG_EMC141X', if_true:
> >> files('emc141x.c'))
> >> > >> > >  softmmu_ss.add(when: 'CONFIG_ADM1272', if_true:
> >> files('adm1272.c'))
> >> > >> > >  softmmu_ss.add(when: 'CONFIG_MAX34451', if_true:
> >> files('max34451.c'))
> >> > >> > > +softmmu_ss.add(when: 'CONFIG_AMDSBTSI', if_true:
> >> > >> files('tmp_sbtsi.c'))
> >> > >> > > diff --git a/hw/sensor/tmp_sbtsi.c b/hw/sensor/tmp_sbtsi.c
> >> > >> > > new file mode 100644
> >> > >> > > index 0000000000..b68c7ebf61
> >> > >> > > --- /dev/null
> >> > >> > > +++ b/hw/sensor/tmp_sbtsi.c
> >> > >> > > @@ -0,0 +1,393 @@
> >> > >> > > +/*
> >> > >> > > + * AMD SBI Temperature Sensor Interface (SB-TSI)
> >> > >> > > + *
> >> > >> > > + * Copyright 2021 Google LLC
> >> > >> > > + *
> >> > >> > > + * This program is free software; you can redistribute it and/or
> >> > >> modify it
> >> > >> > > + * under the terms of the GNU General Public License as
> >> published by
> >> > >> the
> >> > >> > > + * Free Software Foundation; either version 2 of the License, or
> >> > >> > > + * (at your option) any later version.
> >> > >> > > + *
> >> > >> > > + * This program is distributed in the hope that it will be
> >> useful,
> >> > >> but
> >> > >> > > WITHOUT
> >> > >> > > + * ANY WARRANTY; without even the implied warranty of
> >> > >> MERCHANTABILITY or
> >> > >> > > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
> >> > >> License
> >> > >> > > + * for more details.
> >> > >> > > + */
> >> > >> > > +
> >> > >> > > +#include "qemu/osdep.h"
> >> > >> > > +#include "hw/i2c/smbus_slave.h"
> >> > >> > > +#include "hw/irq.h"
> >> > >> > > +#include "migration/vmstate.h"
> >> > >> > > +#include "qapi/error.h"
> >> > >> > > +#include "qapi/visitor.h"
> >> > >> > > +#include "qemu/log.h"
> >> > >> > > +#include "qemu/module.h"
> >> > >> > > +#include "trace.h"
> >> > >> > > +
> >> > >> > > +#define TYPE_SBTSI "sbtsi"
> >> > >> > > +#define SBTSI(obj) OBJECT_CHECK(SBTSIState, (obj), TYPE_SBTSI)
> >> > >> > > +
> >> > >> > > +/**
> >> > >> > > + * SBTSIState:
> >> > >> > > + * temperatures are in units of 0.125 degrees
> >> > >> > > + * @temperature: Temperature
> >> > >> > > + * @limit_low: Lowest temperature
> >> > >> > > + * @limit_high: Highest temperature
> >> > >> > > + * @status: The status register
> >> > >> > > + * @config: The config register
> >> > >> > > + * @alert_config: The config for alarm_l output.
> >> > >> > > + * @addr: The address to read/write for the next cmd.
> >> > >> > > + * @alarm: The alarm_l output pin (GPIO)
> >> > >> > > + */
> >> > >> > > +typedef struct SBTSIState {
> >> > >> > > +    SMBusDevice parent;
> >> > >> > > +
> >> > >> > > +    uint32_t temperature;
> >> > >> > > +    uint32_t limit_low;
> >> > >> > > +    uint32_t limit_high;
> >> > >> > > +    uint8_t status;
> >> > >> > > +    uint8_t config;
> >> > >> > > +    uint8_t alert_config;
> >> > >> > > +    uint8_t addr;
> >> > >> > > +    qemu_irq alarm;
> >> > >> > > +} SBTSIState;
> >> > >> > > +
> >> > >> > > +/*
> >> > >> > > + * SB-TSI registers only support SMBus byte data access. "_INT"
> >> > >> registers
> >> > >> > > are
> >> > >> > > + * the integer part of a temperature value or limit, and "_DEC"
> >> > >> registers
> >> > >> > > are
> >> > >> > > + * corresponding decimal parts.
> >> > >> > > + */
> >> > >> > > +#define SBTSI_REG_TEMP_INT      0x01 /* RO */
> >> > >> > > +#define SBTSI_REG_STATUS        0x02 /* RO */
> >> > >> > > +#define SBTSI_REG_CONFIG        0x03 /* RO */
> >> > >> > > +#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */
> >> > >> > > +#define SBTSI_REG_TEMP_LOW_INT  0x08 /* RW */
> >> > >> > > +#define SBTSI_REG_CONFIG_WR     0x09 /* RW */
> >> > >> > > +#define SBTSI_REG_TEMP_DEC      0x10 /* RO */
> >> > >> > > +#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */
> >> > >> > > +#define SBTSI_REG_TEMP_LOW_DEC  0x14 /* RW */
> >> > >> > > +#define SBTSI_REG_ALERT_CONFIG  0xBF /* RW */
> >> > >> > > +#define SBTSI_REG_MAN           0xFE /* RO */
> >> > >> > > +#define SBTSI_REG_REV           0xFF /* RO */
> >> > >> > > +
> >> > >> > > +#define SBTSI_STATUS_HIGH_ALERT BIT(4)
> >> > >> > > +#define SBTSI_STATUS_LOW_ALERT  BIT(3)
> >> > >> > > +#define SBTSI_CONFIG_ALERT_MASK BIT(7)
> >> > >> > > +#define SBTSI_ALARM_EN          BIT(0)
> >> > >> > > +
> >> > >> > > +#define SBTSI_LIMIT_LOW_DEFAULT (0)
> >> > >> > > +#define SBTSI_LIMIT_HIGH_DEFAULT (560)
> >> > >> > > +#define SBTSI_MAN_DEFAULT (0)
> >> > >> > > +#define SBTSI_REV_DEFAULT (4)
> >> > >> > > +#define SBTSI_ALARM_L "alarm_l"
> >> > >> > > +
> >> > >> > > +/* The temperature we stored are in units of 0.125 degrees. */
> >> > >> > > +#define SBTSI_TEMP_UNIT_IN_MILLIDEGREE 125
> >> > >> > > +
> >> > >> > > +/*
> >> > >> > > + * The integer part and decimal of the temperature both 8 bits.
> >> > >> > > + * Only the top 3 bits of the decimal parts are used.
> >> > >> > > + * So the max temperature is (2^8-1) + (2^3-1)/8 = 255.875
> >> degrees.
> >> > >> > > + */
> >> > >> > > +#define SBTSI_TEMP_MAX 255875
> >> > >> > > +
> >> > >> > > +/* The integer part of the temperature in terms of 0.125
> >> degrees. */
> >> > >> > > +static uint8_t get_temp_int(uint32_t temp)
> >> > >> > > +{
> >> > >> > > +    return temp >> 3;
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +/*
> >> > >> > > + * The decimal part of the temperature, in terms of 0.125
> >> degrees.
> >> > >> > > + * H/W store it in the top 3 bits so we shift it by 5.
> >> > >> > > + */
> >> > >> > > +static uint8_t get_temp_dec(uint32_t temp)
> >> > >> > > +{
> >> > >> > > +    return (temp & 0x7) << 5;
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +/*
> >> > >> > > + * Compute the temperature using the integer and decimal part,
> >> > >> > > + * in terms of 0.125 degrees. The decimal part are only the top
> >> 3
> >> > >> bits
> >> > >> > > + * so we shift it by 5 here.
> >> > >> > > + */
> >> > >> > > +static uint32_t compute_temp(uint8_t integer, uint8_t decimal)
> >> > >> > > +{
> >> > >> > > +    return (integer << 3) + (decimal >> 5);
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +/* Compute new temp with new int part of the temperature. */
> >> > >> > > +static uint32_t compute_temp_int(uint32_t temp, uint8_t integer)
> >> > >> > > +{
> >> > >> > > +    return compute_temp(integer, get_temp_dec(temp));
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +/* Compute new temp with new dec part of the temperature. */
> >> > >> > > +static uint32_t compute_temp_dec(uint32_t temp, uint8_t decimal)
> >> > >> > > +{
> >> > >> > > +    return compute_temp(get_temp_int(temp), decimal);
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +/* The integer part of the temperature. */
> >> > >> > > +static void sbtsi_update_status(SBTSIState *s)
> >> > >> > > +{
> >> > >> > > +    s->status = 0;
> >> > >> > > +    if (s->alert_config & SBTSI_ALARM_EN) {
> >> > >> > > +        if (s->temperature >= s->limit_high) {
> >> > >> > > +            s->status |= SBTSI_STATUS_HIGH_ALERT;
> >> > >> > > +        }
> >> > >> > > +        if (s->temperature <= s->limit_low) {
> >> > >> > > +            s->status |= SBTSI_STATUS_LOW_ALERT;
> >> > >> > > +        }
> >> > >> > > +    }
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +static void sbtsi_update_alarm(SBTSIState *s)
> >> > >> > > +{
> >> > >> > > +    sbtsi_update_status(s);
> >> > >> > > +    if (s->status != 0 && !(s->config &
> >> SBTSI_CONFIG_ALERT_MASK)) {
> >> > >> > > +        qemu_irq_raise(s->alarm);
> >> > >> > > +    } else {
> >> > >> > > +        qemu_irq_lower(s->alarm);
> >> > >> > > +    }
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +static uint8_t sbtsi_read_byte(SMBusDevice *d)
> >> > >> > > +{
> >> > >> > > +    SBTSIState *s = SBTSI(d);
> >> > >> > > +    uint8_t data = 0;
> >> > >> > > +
> >> > >> > > +    switch (s->addr) {
> >> > >> > > +    case SBTSI_REG_TEMP_INT:
> >> > >> > > +        data = get_temp_int(s->temperature);
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_TEMP_DEC:
> >> > >> > > +        data = get_temp_dec(s->temperature);
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_TEMP_HIGH_INT:
> >> > >> > > +        data = get_temp_int(s->limit_high);
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_TEMP_LOW_INT:
> >> > >> > > +        data = get_temp_int(s->limit_low);
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_TEMP_HIGH_DEC:
> >> > >> > > +        data = get_temp_dec(s->limit_high);
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_TEMP_LOW_DEC:
> >> > >> > > +        data = get_temp_dec(s->limit_low);
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_CONFIG:
> >> > >> > > +    case SBTSI_REG_CONFIG_WR:
> >> > >> > > +        data = s->config;
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_STATUS:
> >> > >> > > +        sbtsi_update_alarm(s);
> >> > >> > > +        data = s->status;
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_ALERT_CONFIG:
> >> > >> > > +        data = s->alert_config;
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_MAN:
> >> > >> > > +        data = SBTSI_MAN_DEFAULT;
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_REV:
> >> > >> > > +        data = SBTSI_REV_DEFAULT;
> >> > >> > > +        break;
> >> > >>
> >> > >> Does this device do some sort of auto-increment on the address when
> >> > >> reading/writing?
> >> > >>
> >> > >
> >> > > +Hao Wu <[e-mail]>   - Please take a look at the above
> >> > > question.  I imagine it's a while since you've thought about it, but
> >> please
> >> > > double check :)
> >> > > Thanks!
> >> > >
> >> > >
> >> > >> Other than that possible issue, I don't see anything else, it's
> >> pretty
> >> > >> straightforward.
> >> > >>
> >> > >> > > +
> >> > >> > > +    default:
> >> > >> > > +        qemu_log_mask(LOG_GUEST_ERROR,
> >> > >> > > +                "%s: reading from invalid reg: 0x%02x\n",
> >> > >> > > +                __func__, s->addr);
> >> > >> > > +        break;
> >> > >> > > +    }
> >> > >> > > +
> >> > >> > > +    trace_tmp_sbtsi_read_data(s->addr, data);
> >> > >> > > +    return data;
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +static void sbtsi_write(SBTSIState *s, uint8_t data)
> >> > >> > > +{
> >> > >> > > +    trace_tmp_sbtsi_write_data(s->addr, data);
> >> > >> > > +    switch (s->addr) {
> >> > >> > > +    case SBTSI_REG_CONFIG_WR:
> >> > >> > > +        s->config = data;
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_TEMP_HIGH_INT:
> >> > >> > > +        s->limit_high = compute_temp_int(s->limit_high, data);
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_TEMP_LOW_INT:
> >> > >> > > +        s->limit_low = compute_temp_int(s->limit_low, data);
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_TEMP_HIGH_DEC:
> >> > >> > > +        s->limit_high = compute_temp_dec(s->limit_high, data);
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_TEMP_LOW_DEC:
> >> > >> > > +        s->limit_low = compute_temp_dec(s->limit_low, data);
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_ALERT_CONFIG:
> >> > >> > > +        s->alert_config = data;
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    case SBTSI_REG_TEMP_INT:
> >> > >> > > +    case SBTSI_REG_TEMP_DEC:
> >> > >> > > +    case SBTSI_REG_CONFIG:
> >> > >> > > +    case SBTSI_REG_STATUS:
> >> > >> > > +    case SBTSI_REG_MAN:
> >> > >> > > +    case SBTSI_REG_REV:
> >> > >> > > +        qemu_log_mask(LOG_GUEST_ERROR,
> >> > >> > > +                "%s: writing to read only reg: 0x%02x data:
> >> > >> 0x%02x\n",
> >> > >> > > +                __func__, s->addr, data);
> >> > >> > > +        break;
> >> > >> > > +
> >> > >> > > +    default:
> >> > >> > > +        qemu_log_mask(LOG_GUEST_ERROR,
> >> > >> > > +                "%s: writing to invalid reg: 0x%02x data:
> >> 0x%02x\n",
> >> > >> > > +                __func__, s->addr, data);
> >> > >> > > +        break;
> >> > >> > > +    }
> >> > >> > > +    sbtsi_update_alarm(s);
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +static int sbtsi_write_data(SMBusDevice *d, uint8_t *buf,
> >> uint8_t
> >> > >> len)
> >> > >> > > +{
> >> > >> > > +    SBTSIState *s = SBTSI(d);
> >> > >> > > +
> >> > >> > > +    if (len == 0) {
> >> > >> > > +        qemu_log_mask(LOG_GUEST_ERROR, "%s: writing empty
> >> data\n",
> >> > >> > > __func__);
> >> > >> > > +        return -1;
> >> > >> > > +    }
> >> > >> > > +
> >> > >> > > +    s->addr = buf[0];
> >> > >> > > +    if (len > 1) {
> >> > >> > > +        sbtsi_write(s, buf[1]);
> >> > >> > > +        if (len > 2) {
> >> > >> > > +            qemu_log_mask(LOG_GUEST_ERROR, "%s: extra data at
> >> end\n",
> >> > >> > > __func__);
> >> > >> > > +        }
> >> > >> > > +    }
> >> > >> > > +    return 0;
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +/* Units are millidegrees. */
> >> > >> > > +static void sbtsi_get_temperature(Object *obj, Visitor *v,
> >> const char
> >> > >> > > *name,
> >> > >> > > +                                  void *opaque, Error **errp)
> >> > >> > > +{
> >> > >> > > +    SBTSIState *s = SBTSI(obj);
> >> > >> > > +    uint32_t temp = s->temperature *
> >> SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
> >> > >> > > +
> >> > >> > > +    visit_type_uint32(v, name, &temp, errp);
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +/* Units are millidegrees. */
> >> > >> > > +static void sbtsi_set_temperature(Object *obj, Visitor *v,
> >> const char
> >> > >> > > *name,
> >> > >> > > +                                  void *opaque, Error **errp)
> >> > >> > > +{
> >> > >> > > +    SBTSIState *s = SBTSI(obj);
> >> > >> > > +    uint32_t temp;
> >> > >> > > +
> >> > >> > > +    if (!visit_type_uint32(v, name, &temp, errp)) {
> >> > >> > > +        return;
> >> > >> > > +    }
> >> > >> > > +    if (temp > SBTSI_TEMP_MAX) {
> >> > >> > > +        error_setg(errp, "value %" PRIu32 ".%03" PRIu32 " C is
> >> out of
> >> > >> > > range",
> >> > >> > > +                   temp / 1000, temp % 1000);
> >> > >> > > +        return;
> >> > >> > > +    }
> >> > >> > > +
> >> > >> > > +    s->temperature = temp / SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
> >> > >> > > +    sbtsi_update_alarm(s);
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +static int sbtsi_post_load(void *opaque, int version_id)
> >> > >> > > +{
> >> > >> > > +    SBTSIState *s = opaque;
> >> > >> > > +
> >> > >> > > +    sbtsi_update_alarm(s);
> >> > >> > > +    return 0;
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +static const VMStateDescription vmstate_sbtsi = {
> >> > >> > > +    .name = "SBTSI",
> >> > >> > > +    .version_id = 0,
> >> > >> > > +    .minimum_version_id = 0,
> >> > >> > > +    .post_load = sbtsi_post_load,
> >> > >> > > +    .fields = (VMStateField[]) {
> >> > >> > > +        VMSTATE_UINT32(temperature, SBTSIState),
> >> > >> > > +        VMSTATE_UINT32(limit_low, SBTSIState),
> >> > >> > > +        VMSTATE_UINT32(limit_high, SBTSIState),
> >> > >> > > +        VMSTATE_UINT8(config, SBTSIState),
> >> > >> > > +        VMSTATE_UINT8(status, SBTSIState),
> >> > >> > > +        VMSTATE_UINT8(addr, SBTSIState),
> >> > >> > > +        VMSTATE_END_OF_LIST()
> >> > >> > > +    }
> >> > >> > > +};
> >> > >> > > +
> >> > >> > > +static void sbtsi_enter_reset(Object *obj, ResetType type)
> >> > >> > > +{
> >> > >> > > +    SBTSIState *s = SBTSI(obj);
> >> > >> > > +
> >> > >> > > +    s->config = 0;
> >> > >> > > +    s->limit_low = SBTSI_LIMIT_LOW_DEFAULT;
> >> > >> > > +    s->limit_high = SBTSI_LIMIT_HIGH_DEFAULT;
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +static void sbtsi_hold_reset(Object *obj)
> >> > >> > > +{
> >> > >> > > +    SBTSIState *s = SBTSI(obj);
> >> > >> > > +
> >> > >> > > +    qemu_irq_lower(s->alarm);
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +static void sbtsi_init(Object *obj)
> >> > >> > > +{
> >> > >> > > +    SBTSIState *s = SBTSI(obj);
> >> > >> > > +
> >> > >> > > +    /* Current temperature in millidegrees. */
> >> > >> > > +    object_property_add(obj, "temperature", "uint32",
> >> > >> > > +                        sbtsi_get_temperature,
> >> sbtsi_set_temperature,
> >> > >> > > +                        NULL, NULL);
> >> > >> > > +    qdev_init_gpio_out_named(DEVICE(obj), &s->alarm,
> >> SBTSI_ALARM_L,
> >> > >> 0);
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +static void sbtsi_class_init(ObjectClass *klass, void *data)
> >> > >> > > +{
> >> > >> > > +    ResettableClass *rc = RESETTABLE_CLASS(klass);
> >> > >> > > +    DeviceClass *dc = DEVICE_CLASS(klass);
> >> > >> > > +    SMBusDeviceClass *k = SMBUS_DEVICE_CLASS(klass);
> >> > >> > > +
> >> > >> > > +    dc->desc = "SB-TSI Temperature Sensor";
> >> > >> > > +    dc->vmsd = &vmstate_sbtsi;
> >> > >> > > +    k->write_data = sbtsi_write_data;
> >> > >> > > +    k->receive_byte = sbtsi_read_byte;
> >> > >> > > +    rc->phases.enter = sbtsi_enter_reset;
> >> > >> > > +    rc->phases.hold = sbtsi_hold_reset;
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +static const TypeInfo sbtsi_info = {
> >> > >> > > +    .name          = TYPE_SBTSI,
> >> > >> > > +    .parent        = TYPE_SMBUS_DEVICE,
> >> > >> > > +    .instance_size = sizeof(SBTSIState),
> >> > >> > > +    .instance_init = sbtsi_init,
> >> > >> > > +    .class_init    = sbtsi_class_init,
> >> > >> > > +};
> >> > >> > > +
> >> > >> > > +static void sbtsi_register_types(void)
> >> > >> > > +{
> >> > >> > > +    type_register_static(&sbtsi_info);
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +type_init(sbtsi_register_types)
> >> > >> > > diff --git a/hw/sensor/trace-events b/hw/sensor/trace-events
> >> > >> > > new file mode 100644
> >> > >> > > index 0000000000..21ab3809e2
> >> > >> > > --- /dev/null
> >> > >> > > +++ b/hw/sensor/trace-events
> >> > >> > > @@ -0,0 +1,5 @@
> >> > >> > > +# See docs/devel/tracing.rst for syntax documentation.
> >> > >> > > +
> >> > >> > > +# tmp_sbtsi.c
> >> > >> > > +tmp_sbtsi_write_data(uint8_t addr, uint8_t value) "SBTSI write
> >> > >> > > addr:0x%02x data: 0x%02x"
> >> > >> > > +tmp_sbtsi_read_data(uint8_t addr, uint8_t value) "SBTSI read
> >> > >> addr:0x%02x
> >> > >> > > data: 0x%02x"
> >> > >> > > diff --git a/hw/sensor/trace.h b/hw/sensor/trace.h
> >> > >> > > new file mode 100644
> >> > >> > > index 0000000000..e4721560b0
> >> > >> > > --- /dev/null
> >> > >> > > +++ b/hw/sensor/trace.h
> >> > >> > > @@ -0,0 +1 @@
> >> > >> > > +#include "trace/trace-hw_sensor.h"
> >> > >> > > diff --git a/meson.build b/meson.build
> >> > >> > > index 53065e96ec..f8ab0bf74e 100644
> >> > >> > > --- a/meson.build
> >> > >> > > +++ b/meson.build
> >> > >> > > @@ -2494,6 +2494,7 @@ if have_system
> >> > >> > >      'hw/rtc',
> >> > >> > >      'hw/s390x',
> >> > >> > >      'hw/scsi',
> >> > >> > > +    'hw/sensor',
> >> > >> > >      'hw/sd',
> >> > >> > >      'hw/sh4',
> >> > >> > >      'hw/sparc',
> >> > >> > > diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
> >> > >> > > index 37e1eaa449..d1a8c38f74 100644
> >> > >> > > --- a/tests/qtest/meson.build
> >> > >> > > +++ b/tests/qtest/meson.build
> >> > >> > > @@ -254,6 +254,7 @@ qos_test_ss.add(
> >> > >> > >    'spapr-phb-test.c',
> >> > >> > >    'tmp105-test.c',
> >> > >> > >    'emc141x-test.c',
> >> > >> > > +  'tmp_sbtsi-test.c',
> >> > >> > >    'usb-hcd-ohci-test.c',
> >> > >> > >    'virtio-test.c',
> >> > >> > >    'virtio-blk-test.c',
> >> > >> > > diff --git a/tests/qtest/tmp_sbtsi-test.c
> >> > >> b/tests/qtest/tmp_sbtsi-test.c
> >> > >> > > new file mode 100644
> >> > >> > > index 0000000000..7f5fafacc7
> >> > >> > > --- /dev/null
> >> > >> > > +++ b/tests/qtest/tmp_sbtsi-test.c
> >> > >> > > @@ -0,0 +1,180 @@
> >> > >> > > +/*
> >> > >> > > + * QTests for the SBTSI temperature sensor
> >> > >> > > + *
> >> > >> > > + * Copyright 2020 Google LLC
> >> > >> > > + *
> >> > >> > > + * This program is free software; you can redistribute it and/or
> >> > >> modify it
> >> > >> > > + * under the terms of the GNU General Public License as
> >> published by
> >> > >> the
> >> > >> > > + * Free Software Foundation; either version 2 of the License, or
> >> > >> > > + * (at your option) any later version.
> >> > >> > > + *
> >> > >> > > + * This program is distributed in the hope that it will be
> >> useful,
> >> > >> but
> >> > >> > > WITHOUT
> >> > >> > > + * ANY WARRANTY; without even the implied warranty of
> >> > >> MERCHANTABILITY or
> >> > >> > > + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public
> >> > >> License
> >> > >> > > + * for more details.
> >> > >> > > + */
> >> > >> > > +
> >> > >> > > +#include "qemu/osdep.h"
> >> > >> > > +
> >> > >> > > +#include "libqtest-single.h"
> >> > >> > > +#include "libqos/qgraph.h"
> >> > >> > > +#include "libqos/i2c.h"
> >> > >> > > +#include "qapi/qmp/qdict.h"
> >> > >> > > +#include "qemu/bitops.h"
> >> > >> > > +
> >> > >> > > +#define TEST_ID   "sbtsi-test"
> >> > >> > > +#define TEST_ADDR (0x4c)
> >> > >> > > +
> >> > >> > > +/*
> >> > >> > > + * SB-TSI registers only support SMBus byte data access. "_INT"
> >> > >> registers
> >> > >> > > are
> >> > >> > > + * the integer part of a temperature value or limit, and "_DEC"
> >> > >> registers
> >> > >> > > are
> >> > >> > > + * corresponding decimal parts.
> >> > >> > > + */
> >> > >> > > +#define REG_TEMP_INT      0x01 /* RO */
> >> > >> > > +#define REG_STATUS        0x02 /* RO */
> >> > >> > > +#define REG_CONFIG        0x03 /* RO */
> >> > >> > > +#define REG_TEMP_HIGH_INT 0x07 /* RW */
> >> > >> > > +#define REG_TEMP_LOW_INT  0x08 /* RW */
> >> > >> > > +#define REG_CONFIG_WR     0x09 /* RW */
> >> > >> > > +#define REG_TEMP_DEC      0x10 /* RO */
> >> > >> > > +#define REG_TEMP_HIGH_DEC 0x13 /* RW */
> >> > >> > > +#define REG_TEMP_LOW_DEC  0x14 /* RW */
> >> > >> > > +#define REG_ALERT_CONFIG  0xBF /* RW */
> >> > >> > > +
> >> > >> > > +#define STATUS_HIGH_ALERT BIT(4)
> >> > >> > > +#define STATUS_LOW_ALERT  BIT(3)
> >> > >> > > +#define CONFIG_ALERT_MASK BIT(7)
> >> > >> > > +#define ALARM_EN          BIT(0)
> >> > >> > > +
> >> > >> > > +/* The temperature stored are in units of 0.125 degrees. */
> >> > >> > > +#define TEMP_UNIT_IN_MILLIDEGREE 125
> >> > >> > > +#define LIMIT_LOW (10500)
> >> > >> > > +#define LIMIT_HIGH (55125)
> >> > >> > > +
> >> > >> > > +static uint32_t qmp_sbtsi_get_temperature(const char *id)
> >> > >> > > +{
> >> > >> > > +    QDict *response;
> >> > >> > > +    int ret;
> >> > >> > > +
> >> > >> > > +    response = qmp("{ 'execute': 'qom-get', 'arguments': {
> >> 'path':
> >> > >> %s, "
> >> > >> > > +                   "'property': 'temperature' } }", id);
> >> > >> > > +    g_assert(qdict_haskey(response, "return"));
> >> > >> > > +    ret = (uint32_t)qdict_get_int(response, "return");
> >> > >> > > +    qobject_unref(response);
> >> > >> > > +    return ret;
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +static void qmp_sbtsi_set_temperature(const char *id, uint32_t
> >> value)
> >> > >> > > +{
> >> > >> > > +    QDict *response;
> >> > >> > > +
> >> > >> > > +    response = qmp("{ 'execute': 'qom-set', 'arguments': {
> >> 'path':
> >> > >> %s, "
> >> > >> > > +                   "'property': 'temperature', 'value': %d }
> >> }", id,
> >> > >> > > value);
> >> > >> > > +    g_assert(qdict_haskey(response, "return"));
> >> > >> > > +    qobject_unref(response);
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +/*
> >> > >> > > + * Compute the temperature using the integer and decimal part
> >> and
> >> > >> return
> >> > >> > > + * millidegrees. The decimal part are only the top 3 bits so we
> >> > >> shift it
> >> > >> > > by
> >> > >> > > + * 5 here.
> >> > >> > > + */
> >> > >> > > +static uint32_t regs_to_temp(uint8_t integer, uint8_t decimal)
> >> > >> > > +{
> >> > >> > > +    return ((integer << 3) + (decimal >> 5)) *
> >> > >> TEMP_UNIT_IN_MILLIDEGREE;
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +/*
> >> > >> > > + * Compute the integer and decimal parts of the temperature in
> >> > >> > > millidegrees.
> >> > >> > > + * H/W store the decimal in the top 3 bits so we shift it by 5.
> >> > >> > > + */
> >> > >> > > +static void temp_to_regs(uint32_t temp, uint8_t *integer,
> >> uint8_t
> >> > >> > > *decimal)
> >> > >> > > +{
> >> > >> > > +    temp /= TEMP_UNIT_IN_MILLIDEGREE;
> >> > >> > > +    *integer = temp >> 3;
> >> > >> > > +    *decimal = (temp & 0x7) << 5;
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +static void tx_rx(void *obj, void *data, QGuestAllocator *alloc)
> >> > >> > > +{
> >> > >> > > +    uint16_t value;
> >> > >> > > +    uint8_t integer, decimal;
> >> > >> > > +    QI2CDevice *i2cdev = (QI2CDevice *)obj;
> >> > >> > > +
> >> > >> > > +    /* Test default values */
> >> > >> > > +    value = qmp_sbtsi_get_temperature(TEST_ID);
> >> > >> > > +    g_assert_cmpuint(value, ==, 0);
> >> > >> > > +
> >> > >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
> >> > >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
> >> > >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 0);
> >> > >> > > +
> >> > >> > > +    /* Test setting temperature */
> >> > >> > > +    qmp_sbtsi_set_temperature(TEST_ID, 20000);
> >> > >> > > +    value = qmp_sbtsi_get_temperature(TEST_ID);
> >> > >> > > +    g_assert_cmpuint(value, ==, 20000);
> >> > >> > > +
> >> > >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_INT);
> >> > >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
> >> > >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 20000);
> >> > >> > > +
> >> > >> > > +    /* Set alert mask in config */
> >> > >> > > +    i2c_set8(i2cdev, REG_CONFIG_WR, CONFIG_ALERT_MASK);
> >> > >> > > +    value = i2c_get8(i2cdev, REG_CONFIG);
> >> > >> > > +    g_assert_cmphex(value, ==, CONFIG_ALERT_MASK);
> >> > >> > > +    /* Enable alarm_en */
> >> > >> > > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, ALARM_EN);
> >> > >> > > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
> >> > >> > > +    g_assert_cmphex(value, ==, ALARM_EN);
> >> > >> > > +
> >> > >> > > +    /* Test setting limits */
> >> > >> > > +    /* Limit low = 10.500 */
> >> > >> > > +    temp_to_regs(LIMIT_LOW, &integer, &decimal);
> >> > >> > > +    i2c_set8(i2cdev, REG_TEMP_LOW_INT, integer);
> >> > >> > > +    i2c_set8(i2cdev, REG_TEMP_LOW_DEC, decimal);
> >> > >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_LOW_INT);
> >> > >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_LOW_DEC);
> >> > >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==,
> >> LIMIT_LOW);
> >> > >> > > +    /* Limit high = 55.125 */
> >> > >> > > +    temp_to_regs(LIMIT_HIGH, &integer, &decimal);
> >> > >> > > +    i2c_set8(i2cdev, REG_TEMP_HIGH_INT, integer);
> >> > >> > > +    i2c_set8(i2cdev, REG_TEMP_HIGH_DEC, decimal);
> >> > >> > > +    integer = i2c_get8(i2cdev, REG_TEMP_HIGH_INT);
> >> > >> > > +    decimal = i2c_get8(i2cdev, REG_TEMP_HIGH_DEC);
> >> > >> > > +    g_assert_cmpuint(regs_to_temp(integer, decimal), ==,
> >> LIMIT_HIGH);
> >> > >> > > +    /* No alert is generated. */
> >> > >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> >> > >> > > +    g_assert_cmphex(value, ==, 0);
> >> > >> > > +
> >> > >> > > +    /* Test alert for low temperature */
> >> > >> > > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_LOW);
> >> > >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> >> > >> > > +    g_assert_cmphex(value, ==, STATUS_LOW_ALERT);
> >> > >> > > +
> >> > >> > > +    /* Test alert for high temperature */
> >> > >> > > +    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_HIGH);
> >> > >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> >> > >> > > +    g_assert_cmphex(value, ==, STATUS_HIGH_ALERT);
> >> > >> > > +
> >> > >> > > +    /* Disable alarm_en */
> >> > >> > > +    i2c_set8(i2cdev, REG_ALERT_CONFIG, 0);
> >> > >> > > +    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
> >> > >> > > +    g_assert_cmphex(value, ==, 0);
> >> > >> > > +    /* No alert when alarm_en is false. */
> >> > >> > > +    value = i2c_get8(i2cdev, REG_STATUS);
> >> > >> > > +    g_assert_cmphex(value, ==, 0);
> >> > >> > > +}
> >> > >> > > +
> >> > >> > > +static void sbtsi_register_nodes(void)
> >> > >> > > +{
> >> > >> > > +    QOSGraphEdgeOptions opts = {
> >> > >> > > +        .extra_device_opts = "id=" TEST_ID ",address=0x4c"
> >> > >> > > +    };
> >> > >> > > +    add_qi2c_address(&opts, &(QI2CAddress) { TEST_ADDR });
> >> > >> > > +
> >> > >> > > +    qos_node_create_driver("sbtsi", i2c_device_create);
> >> > >> > > +    qos_node_consumes("sbtsi", "i2c-bus", &opts);
> >> > >> > > +
> >> > >> > > +    qos_add_test("tx-rx", "sbtsi", tx_rx, NULL);
> >> > >> > > +}
> >> > >> > > +libqos_init(sbtsi_register_nodes);
> >> > >> > > --
> >> > >> >
> >> > >> >
> >> > >> > + Corey for i2c maintainer.  The new sensor directory is mostly if
> >> not
> >> > >> > entirely i2c devices.  I didn't create a maintainer entry for this
> >> i2c
> >> > >> > device, but I can if desired and send out a v2.
> >> > >>
> >> > >> Yeah, I guess I should be maintainer there.  I'll queue up a change
> >> for
> >> > >> that.  Thanks.
> >> > >>
> >> > >> -corey
> >> > >>
> >> > >> >
> >> > >> >
> >> > >> > > 2.34.1.575.g55b058a8bb-goog
> >> > >> > >
> >> > >> > >
> >> > >>
> >> > >
> >>
> >

Patch

diff --git a/hw/sensor/Kconfig b/hw/sensor/Kconfig
index 9c8a049b06..27f6f79c84 100644
--- a/hw/sensor/Kconfig
+++ b/hw/sensor/Kconfig
@@ -21,3 +21,7 @@  config ADM1272
 config MAX34451
     bool
     depends on I2C
+
+config AMDSBTSI
+    bool
+    depends on I2C
diff --git a/hw/sensor/meson.build b/hw/sensor/meson.build
index 059c4ca935..f7b0e645eb 100644
--- a/hw/sensor/meson.build
+++ b/hw/sensor/meson.build
@@ -4,3 +4,4 @@  softmmu_ss.add(when: 'CONFIG_DPS310', if_true: files('dps310.c'))
 softmmu_ss.add(when: 'CONFIG_EMC141X', if_true: files('emc141x.c'))
 softmmu_ss.add(when: 'CONFIG_ADM1272', if_true: files('adm1272.c'))
 softmmu_ss.add(when: 'CONFIG_MAX34451', if_true: files('max34451.c'))
+softmmu_ss.add(when: 'CONFIG_AMDSBTSI', if_true: files('tmp_sbtsi.c'))
diff --git a/hw/sensor/tmp_sbtsi.c b/hw/sensor/tmp_sbtsi.c
new file mode 100644
index 0000000000..b68c7ebf61
--- /dev/null
+++ b/hw/sensor/tmp_sbtsi.c
@@ -0,0 +1,393 @@ 
+/*
+ * AMD SBI Temperature Sensor Interface (SB-TSI)
+ *
+ * Copyright 2021 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "qemu/osdep.h"
+#include "hw/i2c/smbus_slave.h"
+#include "hw/irq.h"
+#include "migration/vmstate.h"
+#include "qapi/error.h"
+#include "qapi/visitor.h"
+#include "qemu/log.h"
+#include "qemu/module.h"
+#include "trace.h"
+
+#define TYPE_SBTSI "sbtsi"
+#define SBTSI(obj) OBJECT_CHECK(SBTSIState, (obj), TYPE_SBTSI)
+
+/**
+ * SBTSIState:
+ * temperatures are in units of 0.125 degrees
+ * @temperature: Temperature
+ * @limit_low: Lowest temperature
+ * @limit_high: Highest temperature
+ * @status: The status register
+ * @config: The config register
+ * @alert_config: The config for alarm_l output.
+ * @addr: The address to read/write for the next cmd.
+ * @alarm: The alarm_l output pin (GPIO)
+ */
+typedef struct SBTSIState {
+    SMBusDevice parent;
+
+    uint32_t temperature;
+    uint32_t limit_low;
+    uint32_t limit_high;
+    uint8_t status;
+    uint8_t config;
+    uint8_t alert_config;
+    uint8_t addr;
+    qemu_irq alarm;
+} SBTSIState;
+
+/*
+ * SB-TSI registers only support SMBus byte data access. "_INT" registers are
+ * the integer part of a temperature value or limit, and "_DEC" registers are
+ * corresponding decimal parts.
+ */
+#define SBTSI_REG_TEMP_INT      0x01 /* RO */
+#define SBTSI_REG_STATUS        0x02 /* RO */
+#define SBTSI_REG_CONFIG        0x03 /* RO */
+#define SBTSI_REG_TEMP_HIGH_INT 0x07 /* RW */
+#define SBTSI_REG_TEMP_LOW_INT  0x08 /* RW */
+#define SBTSI_REG_CONFIG_WR     0x09 /* RW */
+#define SBTSI_REG_TEMP_DEC      0x10 /* RO */
+#define SBTSI_REG_TEMP_HIGH_DEC 0x13 /* RW */
+#define SBTSI_REG_TEMP_LOW_DEC  0x14 /* RW */
+#define SBTSI_REG_ALERT_CONFIG  0xBF /* RW */
+#define SBTSI_REG_MAN           0xFE /* RO */
+#define SBTSI_REG_REV           0xFF /* RO */
+
+#define SBTSI_STATUS_HIGH_ALERT BIT(4)
+#define SBTSI_STATUS_LOW_ALERT  BIT(3)
+#define SBTSI_CONFIG_ALERT_MASK BIT(7)
+#define SBTSI_ALARM_EN          BIT(0)
+
+#define SBTSI_LIMIT_LOW_DEFAULT (0)
+#define SBTSI_LIMIT_HIGH_DEFAULT (560)
+#define SBTSI_MAN_DEFAULT (0)
+#define SBTSI_REV_DEFAULT (4)
+#define SBTSI_ALARM_L "alarm_l"
+
+/* The temperature we stored are in units of 0.125 degrees. */
+#define SBTSI_TEMP_UNIT_IN_MILLIDEGREE 125
+
+/*
+ * The integer part and decimal of the temperature both 8 bits.
+ * Only the top 3 bits of the decimal parts are used.
+ * So the max temperature is (2^8-1) + (2^3-1)/8 = 255.875 degrees.
+ */
+#define SBTSI_TEMP_MAX 255875
+
+/* The integer part of the temperature in terms of 0.125 degrees. */
+static uint8_t get_temp_int(uint32_t temp)
+{
+    return temp >> 3;
+}
+
+/*
+ * The decimal part of the temperature, in terms of 0.125 degrees.
+ * H/W store it in the top 3 bits so we shift it by 5.
+ */
+static uint8_t get_temp_dec(uint32_t temp)
+{
+    return (temp & 0x7) << 5;
+}
+
+/*
+ * Compute the temperature using the integer and decimal part,
+ * in terms of 0.125 degrees. The decimal part are only the top 3 bits
+ * so we shift it by 5 here.
+ */
+static uint32_t compute_temp(uint8_t integer, uint8_t decimal)
+{
+    return (integer << 3) + (decimal >> 5);
+}
+
+/* Compute new temp with new int part of the temperature. */
+static uint32_t compute_temp_int(uint32_t temp, uint8_t integer)
+{
+    return compute_temp(integer, get_temp_dec(temp));
+}
+
+/* Compute new temp with new dec part of the temperature. */
+static uint32_t compute_temp_dec(uint32_t temp, uint8_t decimal)
+{
+    return compute_temp(get_temp_int(temp), decimal);
+}
+
+/* The integer part of the temperature. */
+static void sbtsi_update_status(SBTSIState *s)
+{
+    s->status = 0;
+    if (s->alert_config & SBTSI_ALARM_EN) {
+        if (s->temperature >= s->limit_high) {
+            s->status |= SBTSI_STATUS_HIGH_ALERT;
+        }
+        if (s->temperature <= s->limit_low) {
+            s->status |= SBTSI_STATUS_LOW_ALERT;
+        }
+    }
+}
+
+static void sbtsi_update_alarm(SBTSIState *s)
+{
+    sbtsi_update_status(s);
+    if (s->status != 0 && !(s->config & SBTSI_CONFIG_ALERT_MASK)) {
+        qemu_irq_raise(s->alarm);
+    } else {
+        qemu_irq_lower(s->alarm);
+    }
+}
+
+static uint8_t sbtsi_read_byte(SMBusDevice *d)
+{
+    SBTSIState *s = SBTSI(d);
+    uint8_t data = 0;
+
+    switch (s->addr) {
+    case SBTSI_REG_TEMP_INT:
+        data = get_temp_int(s->temperature);
+        break;
+
+    case SBTSI_REG_TEMP_DEC:
+        data = get_temp_dec(s->temperature);
+        break;
+
+    case SBTSI_REG_TEMP_HIGH_INT:
+        data = get_temp_int(s->limit_high);
+        break;
+
+    case SBTSI_REG_TEMP_LOW_INT:
+        data = get_temp_int(s->limit_low);
+        break;
+
+    case SBTSI_REG_TEMP_HIGH_DEC:
+        data = get_temp_dec(s->limit_high);
+        break;
+
+    case SBTSI_REG_TEMP_LOW_DEC:
+        data = get_temp_dec(s->limit_low);
+        break;
+
+    case SBTSI_REG_CONFIG:
+    case SBTSI_REG_CONFIG_WR:
+        data = s->config;
+        break;
+
+    case SBTSI_REG_STATUS:
+        sbtsi_update_alarm(s);
+        data = s->status;
+        break;
+
+    case SBTSI_REG_ALERT_CONFIG:
+        data = s->alert_config;
+        break;
+
+    case SBTSI_REG_MAN:
+        data = SBTSI_MAN_DEFAULT;
+        break;
+
+    case SBTSI_REG_REV:
+        data = SBTSI_REV_DEFAULT;
+        break;
+
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                "%s: reading from invalid reg: 0x%02x\n",
+                __func__, s->addr);
+        break;
+    }
+
+    trace_tmp_sbtsi_read_data(s->addr, data);
+    return data;
+}
+
+static void sbtsi_write(SBTSIState *s, uint8_t data)
+{
+    trace_tmp_sbtsi_write_data(s->addr, data);
+    switch (s->addr) {
+    case SBTSI_REG_CONFIG_WR:
+        s->config = data;
+        break;
+
+    case SBTSI_REG_TEMP_HIGH_INT:
+        s->limit_high = compute_temp_int(s->limit_high, data);
+        break;
+
+    case SBTSI_REG_TEMP_LOW_INT:
+        s->limit_low = compute_temp_int(s->limit_low, data);
+        break;
+
+    case SBTSI_REG_TEMP_HIGH_DEC:
+        s->limit_high = compute_temp_dec(s->limit_high, data);
+        break;
+
+    case SBTSI_REG_TEMP_LOW_DEC:
+        s->limit_low = compute_temp_dec(s->limit_low, data);
+        break;
+
+    case SBTSI_REG_ALERT_CONFIG:
+        s->alert_config = data;
+        break;
+
+    case SBTSI_REG_TEMP_INT:
+    case SBTSI_REG_TEMP_DEC:
+    case SBTSI_REG_CONFIG:
+    case SBTSI_REG_STATUS:
+    case SBTSI_REG_MAN:
+    case SBTSI_REG_REV:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                "%s: writing to read only reg: 0x%02x data: 0x%02x\n",
+                __func__, s->addr, data);
+        break;
+
+    default:
+        qemu_log_mask(LOG_GUEST_ERROR,
+                "%s: writing to invalid reg: 0x%02x data: 0x%02x\n",
+                __func__, s->addr, data);
+        break;
+    }
+    sbtsi_update_alarm(s);
+}
+
+static int sbtsi_write_data(SMBusDevice *d, uint8_t *buf, uint8_t len)
+{
+    SBTSIState *s = SBTSI(d);
+
+    if (len == 0) {
+        qemu_log_mask(LOG_GUEST_ERROR, "%s: writing empty data\n", __func__);
+        return -1;
+    }
+
+    s->addr = buf[0];
+    if (len > 1) {
+        sbtsi_write(s, buf[1]);
+        if (len > 2) {
+            qemu_log_mask(LOG_GUEST_ERROR, "%s: extra data at end\n", __func__);
+        }
+    }
+    return 0;
+}
+
+/* Units are millidegrees. */
+static void sbtsi_get_temperature(Object *obj, Visitor *v, const char *name,
+                                  void *opaque, Error **errp)
+{
+    SBTSIState *s = SBTSI(obj);
+    uint32_t temp = s->temperature * SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
+
+    visit_type_uint32(v, name, &temp, errp);
+}
+
+/* Units are millidegrees. */
+static void sbtsi_set_temperature(Object *obj, Visitor *v, const char *name,
+                                  void *opaque, Error **errp)
+{
+    SBTSIState *s = SBTSI(obj);
+    uint32_t temp;
+
+    if (!visit_type_uint32(v, name, &temp, errp)) {
+        return;
+    }
+    if (temp > SBTSI_TEMP_MAX) {
+        error_setg(errp, "value %" PRIu32 ".%03" PRIu32 " C is out of range",
+                   temp / 1000, temp % 1000);
+        return;
+    }
+
+    s->temperature = temp / SBTSI_TEMP_UNIT_IN_MILLIDEGREE;
+    sbtsi_update_alarm(s);
+}
+
+static int sbtsi_post_load(void *opaque, int version_id)
+{
+    SBTSIState *s = opaque;
+
+    sbtsi_update_alarm(s);
+    return 0;
+}
+
+static const VMStateDescription vmstate_sbtsi = {
+    .name = "SBTSI",
+    .version_id = 0,
+    .minimum_version_id = 0,
+    .post_load = sbtsi_post_load,
+    .fields = (VMStateField[]) {
+        VMSTATE_UINT32(temperature, SBTSIState),
+        VMSTATE_UINT32(limit_low, SBTSIState),
+        VMSTATE_UINT32(limit_high, SBTSIState),
+        VMSTATE_UINT8(config, SBTSIState),
+        VMSTATE_UINT8(status, SBTSIState),
+        VMSTATE_UINT8(addr, SBTSIState),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static void sbtsi_enter_reset(Object *obj, ResetType type)
+{
+    SBTSIState *s = SBTSI(obj);
+
+    s->config = 0;
+    s->limit_low = SBTSI_LIMIT_LOW_DEFAULT;
+    s->limit_high = SBTSI_LIMIT_HIGH_DEFAULT;
+}
+
+static void sbtsi_hold_reset(Object *obj)
+{
+    SBTSIState *s = SBTSI(obj);
+
+    qemu_irq_lower(s->alarm);
+}
+
+static void sbtsi_init(Object *obj)
+{
+    SBTSIState *s = SBTSI(obj);
+
+    /* Current temperature in millidegrees. */
+    object_property_add(obj, "temperature", "uint32",
+                        sbtsi_get_temperature, sbtsi_set_temperature,
+                        NULL, NULL);
+    qdev_init_gpio_out_named(DEVICE(obj), &s->alarm, SBTSI_ALARM_L, 0);
+}
+
+static void sbtsi_class_init(ObjectClass *klass, void *data)
+{
+    ResettableClass *rc = RESETTABLE_CLASS(klass);
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    SMBusDeviceClass *k = SMBUS_DEVICE_CLASS(klass);
+
+    dc->desc = "SB-TSI Temperature Sensor";
+    dc->vmsd = &vmstate_sbtsi;
+    k->write_data = sbtsi_write_data;
+    k->receive_byte = sbtsi_read_byte;
+    rc->phases.enter = sbtsi_enter_reset;
+    rc->phases.hold = sbtsi_hold_reset;
+}
+
+static const TypeInfo sbtsi_info = {
+    .name          = TYPE_SBTSI,
+    .parent        = TYPE_SMBUS_DEVICE,
+    .instance_size = sizeof(SBTSIState),
+    .instance_init = sbtsi_init,
+    .class_init    = sbtsi_class_init,
+};
+
+static void sbtsi_register_types(void)
+{
+    type_register_static(&sbtsi_info);
+}
+
+type_init(sbtsi_register_types)
diff --git a/hw/sensor/trace-events b/hw/sensor/trace-events
new file mode 100644
index 0000000000..21ab3809e2
--- /dev/null
+++ b/hw/sensor/trace-events
@@ -0,0 +1,5 @@ 
+# See docs/devel/tracing.rst for syntax documentation.
+
+# tmp_sbtsi.c
+tmp_sbtsi_write_data(uint8_t addr, uint8_t value) "SBTSI write addr:0x%02x data: 0x%02x"
+tmp_sbtsi_read_data(uint8_t addr, uint8_t value) "SBTSI read addr:0x%02x data: 0x%02x"
diff --git a/hw/sensor/trace.h b/hw/sensor/trace.h
new file mode 100644
index 0000000000..e4721560b0
--- /dev/null
+++ b/hw/sensor/trace.h
@@ -0,0 +1 @@ 
+#include "trace/trace-hw_sensor.h"
diff --git a/meson.build b/meson.build
index 53065e96ec..f8ab0bf74e 100644
--- a/meson.build
+++ b/meson.build
@@ -2494,6 +2494,7 @@  if have_system
     'hw/rtc',
     'hw/s390x',
     'hw/scsi',
+    'hw/sensor',
     'hw/sd',
     'hw/sh4',
     'hw/sparc',
diff --git a/tests/qtest/meson.build b/tests/qtest/meson.build
index 37e1eaa449..d1a8c38f74 100644
--- a/tests/qtest/meson.build
+++ b/tests/qtest/meson.build
@@ -254,6 +254,7 @@  qos_test_ss.add(
   'spapr-phb-test.c',
   'tmp105-test.c',
   'emc141x-test.c',
+  'tmp_sbtsi-test.c',
   'usb-hcd-ohci-test.c',
   'virtio-test.c',
   'virtio-blk-test.c',
diff --git a/tests/qtest/tmp_sbtsi-test.c b/tests/qtest/tmp_sbtsi-test.c
new file mode 100644
index 0000000000..7f5fafacc7
--- /dev/null
+++ b/tests/qtest/tmp_sbtsi-test.c
@@ -0,0 +1,180 @@ 
+/*
+ * QTests for the SBTSI temperature sensor
+ *
+ * Copyright 2020 Google LLC
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+#include "qemu/osdep.h"
+
+#include "libqtest-single.h"
+#include "libqos/qgraph.h"
+#include "libqos/i2c.h"
+#include "qapi/qmp/qdict.h"
+#include "qemu/bitops.h"
+
+#define TEST_ID   "sbtsi-test"
+#define TEST_ADDR (0x4c)
+
+/*
+ * SB-TSI registers only support SMBus byte data access. "_INT" registers are
+ * the integer part of a temperature value or limit, and "_DEC" registers are
+ * corresponding decimal parts.
+ */
+#define REG_TEMP_INT      0x01 /* RO */
+#define REG_STATUS        0x02 /* RO */
+#define REG_CONFIG        0x03 /* RO */
+#define REG_TEMP_HIGH_INT 0x07 /* RW */
+#define REG_TEMP_LOW_INT  0x08 /* RW */
+#define REG_CONFIG_WR     0x09 /* RW */
+#define REG_TEMP_DEC      0x10 /* RO */
+#define REG_TEMP_HIGH_DEC 0x13 /* RW */
+#define REG_TEMP_LOW_DEC  0x14 /* RW */
+#define REG_ALERT_CONFIG  0xBF /* RW */
+
+#define STATUS_HIGH_ALERT BIT(4)
+#define STATUS_LOW_ALERT  BIT(3)
+#define CONFIG_ALERT_MASK BIT(7)
+#define ALARM_EN          BIT(0)
+
+/* The temperature stored are in units of 0.125 degrees. */
+#define TEMP_UNIT_IN_MILLIDEGREE 125
+#define LIMIT_LOW (10500)
+#define LIMIT_HIGH (55125)
+
+static uint32_t qmp_sbtsi_get_temperature(const char *id)
+{
+    QDict *response;
+    int ret;
+
+    response = qmp("{ 'execute': 'qom-get', 'arguments': { 'path': %s, "
+                   "'property': 'temperature' } }", id);
+    g_assert(qdict_haskey(response, "return"));
+    ret = (uint32_t)qdict_get_int(response, "return");
+    qobject_unref(response);
+    return ret;
+}
+
+static void qmp_sbtsi_set_temperature(const char *id, uint32_t value)
+{
+    QDict *response;
+
+    response = qmp("{ 'execute': 'qom-set', 'arguments': { 'path': %s, "
+                   "'property': 'temperature', 'value': %d } }", id, value);
+    g_assert(qdict_haskey(response, "return"));
+    qobject_unref(response);
+}
+
+/*
+ * Compute the temperature using the integer and decimal part and return
+ * millidegrees. The decimal part are only the top 3 bits so we shift it by
+ * 5 here.
+ */
+static uint32_t regs_to_temp(uint8_t integer, uint8_t decimal)
+{
+    return ((integer << 3) + (decimal >> 5)) * TEMP_UNIT_IN_MILLIDEGREE;
+}
+
+/*
+ * Compute the integer and decimal parts of the temperature in millidegrees.
+ * H/W store the decimal in the top 3 bits so we shift it by 5.
+ */
+static void temp_to_regs(uint32_t temp, uint8_t *integer, uint8_t *decimal)
+{
+    temp /= TEMP_UNIT_IN_MILLIDEGREE;
+    *integer = temp >> 3;
+    *decimal = (temp & 0x7) << 5;
+}
+
+static void tx_rx(void *obj, void *data, QGuestAllocator *alloc)
+{
+    uint16_t value;
+    uint8_t integer, decimal;
+    QI2CDevice *i2cdev = (QI2CDevice *)obj;
+
+    /* Test default values */
+    value = qmp_sbtsi_get_temperature(TEST_ID);
+    g_assert_cmpuint(value, ==, 0);
+
+    integer = i2c_get8(i2cdev, REG_TEMP_INT);
+    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
+    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 0);
+
+    /* Test setting temperature */
+    qmp_sbtsi_set_temperature(TEST_ID, 20000);
+    value = qmp_sbtsi_get_temperature(TEST_ID);
+    g_assert_cmpuint(value, ==, 20000);
+
+    integer = i2c_get8(i2cdev, REG_TEMP_INT);
+    decimal = i2c_get8(i2cdev, REG_TEMP_DEC);
+    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, 20000);
+
+    /* Set alert mask in config */
+    i2c_set8(i2cdev, REG_CONFIG_WR, CONFIG_ALERT_MASK);
+    value = i2c_get8(i2cdev, REG_CONFIG);
+    g_assert_cmphex(value, ==, CONFIG_ALERT_MASK);
+    /* Enable alarm_en */
+    i2c_set8(i2cdev, REG_ALERT_CONFIG, ALARM_EN);
+    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
+    g_assert_cmphex(value, ==, ALARM_EN);
+
+    /* Test setting limits */
+    /* Limit low = 10.500 */
+    temp_to_regs(LIMIT_LOW, &integer, &decimal);
+    i2c_set8(i2cdev, REG_TEMP_LOW_INT, integer);
+    i2c_set8(i2cdev, REG_TEMP_LOW_DEC, decimal);
+    integer = i2c_get8(i2cdev, REG_TEMP_LOW_INT);
+    decimal = i2c_get8(i2cdev, REG_TEMP_LOW_DEC);
+    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, LIMIT_LOW);
+    /* Limit high = 55.125 */
+    temp_to_regs(LIMIT_HIGH, &integer, &decimal);
+    i2c_set8(i2cdev, REG_TEMP_HIGH_INT, integer);
+    i2c_set8(i2cdev, REG_TEMP_HIGH_DEC, decimal);
+    integer = i2c_get8(i2cdev, REG_TEMP_HIGH_INT);
+    decimal = i2c_get8(i2cdev, REG_TEMP_HIGH_DEC);
+    g_assert_cmpuint(regs_to_temp(integer, decimal), ==, LIMIT_HIGH);
+    /* No alert is generated. */
+    value = i2c_get8(i2cdev, REG_STATUS);
+    g_assert_cmphex(value, ==, 0);
+
+    /* Test alert for low temperature */
+    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_LOW);
+    value = i2c_get8(i2cdev, REG_STATUS);
+    g_assert_cmphex(value, ==, STATUS_LOW_ALERT);
+
+    /* Test alert for high temperature */
+    qmp_sbtsi_set_temperature(TEST_ID, LIMIT_HIGH);
+    value = i2c_get8(i2cdev, REG_STATUS);
+    g_assert_cmphex(value, ==, STATUS_HIGH_ALERT);
+
+    /* Disable alarm_en */
+    i2c_set8(i2cdev, REG_ALERT_CONFIG, 0);
+    value = i2c_get8(i2cdev, REG_ALERT_CONFIG);
+    g_assert_cmphex(value, ==, 0);
+    /* No alert when alarm_en is false. */
+    value = i2c_get8(i2cdev, REG_STATUS);
+    g_assert_cmphex(value, ==, 0);
+}
+
+static void sbtsi_register_nodes(void)
+{
+    QOSGraphEdgeOptions opts = {
+        .extra_device_opts = "id=" TEST_ID ",address=0x4c"
+    };
+    add_qi2c_address(&opts, &(QI2CAddress) { TEST_ADDR });
+
+    qos_node_create_driver("sbtsi", i2c_device_create);
+    qos_node_consumes("sbtsi", "i2c-bus", &opts);
+
+    qos_add_test("tx-rx", "sbtsi", tx_rx, NULL);
+}
+libqos_init(sbtsi_register_nodes);