diff mbox series

[v6,8/9] misc: smpro-misc: Add Ampere's Altra SMpro misc driver

Message ID 20211224041352.29405-9-quan@os.amperecomputing.com (mailing list archive)
State Not Applicable
Headers show
Series Add Ampere's Altra SMPro MFD and its child drivers | expand

Commit Message

Quan Nguyen Dec. 24, 2021, 4:13 a.m. UTC
This commit adds driver support for accessing various information
reported by Ampere's SMpro co-processor such as Boot Progress and
other miscellaneous data.

Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com>
---
Change in v6:
  + First introduced in v6 [Quan]

 drivers/mfd/smpro-mfd.c   |   1 +
 drivers/misc/Kconfig      |   7 ++
 drivers/misc/Makefile     |   1 +
 drivers/misc/smpro-misc.c | 177 ++++++++++++++++++++++++++++++++++++++
 4 files changed, 186 insertions(+)
 create mode 100644 drivers/misc/smpro-misc.c

Comments

Lee Jones Dec. 29, 2021, 10:18 a.m. UTC | #1
On Fri, 24 Dec 2021, Quan Nguyen wrote:

> This commit adds driver support for accessing various information
> reported by Ampere's SMpro co-processor such as Boot Progress and
> other miscellaneous data.
> 
> Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com>
> ---
> Change in v6:
>   + First introduced in v6 [Quan]
> 
>  drivers/mfd/smpro-mfd.c   |   1 +

Please pull all of these patches out.

There are no build dependencies here.

>  drivers/misc/Kconfig      |   7 ++
>  drivers/misc/Makefile     |   1 +
>  drivers/misc/smpro-misc.c | 177 ++++++++++++++++++++++++++++++++++++++
>  4 files changed, 186 insertions(+)
>  create mode 100644 drivers/misc/smpro-misc.c
> 
> diff --git a/drivers/mfd/smpro-mfd.c b/drivers/mfd/smpro-mfd.c
> index a7cd64bf9eaa..5611dd30f8f4 100644
> --- a/drivers/mfd/smpro-mfd.c
> +++ b/drivers/mfd/smpro-mfd.c
> @@ -28,6 +28,7 @@ static const struct regmap_config simple_word_regmap_config = {
>  static const struct mfd_cell smpro_devs[] = {
>  	MFD_CELL_NAME("smpro-hwmon"),
>  	MFD_CELL_NAME("smpro-errmon"),
> +	MFD_CELL_NAME("smpro-misc"),

Misc is a Linuxisum which are not allowed in DT.

What does this driver actually do?
Quan Nguyen March 7, 2022, 8:32 a.m. UTC | #2
Dear Lee Jones,

This to reply your comment in https://lkml.org/lkml/2021/12/29/121

Thanks for the review,
- Quan

On 24/12/2021 11:13, Quan Nguyen wrote:
> This commit adds driver support for accessing various information
> reported by Ampere's SMpro co-processor such as Boot Progress and
> other miscellaneous data.
> 
> Signed-off-by: Quan Nguyen <quan@os.amperecomputing.com>
> ---
> Change in v6:
>    + First introduced in v6 [Quan]
> 
>   drivers/mfd/smpro-mfd.c   |   1 +

[Lee Jones]
Please pull all of these patches out.

There are no build dependencies here.

[Quan]
Will separate this smpro-mfd and other child drivers in next version

>   drivers/misc/Kconfig      |   7 ++
>   drivers/misc/Makefile     |   1 +
>   drivers/misc/smpro-misc.c | 177 ++++++++++++++++++++++++++++++++++++++
>   4 files changed, 186 insertions(+)
>   create mode 100644 drivers/misc/smpro-misc.c
> 
> diff --git a/drivers/mfd/smpro-mfd.c b/drivers/mfd/smpro-mfd.c
> index a7cd64bf9eaa..5611dd30f8f4 100644
> --- a/drivers/mfd/smpro-mfd.c
> +++ b/drivers/mfd/smpro-mfd.c
> @@ -28,6 +28,7 @@ static const struct regmap_config simple_word_regmap_config = {
>   static const struct mfd_cell smpro_devs[] = {
>   	MFD_CELL_NAME("smpro-hwmon"),
>   	MFD_CELL_NAME("smpro-errmon"),
> +	MFD_CELL_NAME("smpro-misc"),

[Lee Jones]
Misc is a Linuxisum which are not allowed in DT.

What does this driver actually do?

[Quan]
This drivers is to report the boot progress to BMC and allow BMC to 
configure the Soc Power Limit of Ampere's Altra family processor.
Arnd Bergmann March 7, 2022, 1:16 p.m. UTC | #3
On Mon, Mar 7, 2022 at 9:32 AM Quan Nguyen <quan@os.amperecomputing.com> wrote:
> > diff --git a/drivers/mfd/smpro-mfd.c b/drivers/mfd/smpro-mfd.c
> > index a7cd64bf9eaa..5611dd30f8f4 100644
> > --- a/drivers/mfd/smpro-mfd.c
> > +++ b/drivers/mfd/smpro-mfd.c
> > @@ -28,6 +28,7 @@ static const struct regmap_config simple_word_regmap_config = {
> >   static const struct mfd_cell smpro_devs[] = {
> >       MFD_CELL_NAME("smpro-hwmon"),
> >       MFD_CELL_NAME("smpro-errmon"),
> > +     MFD_CELL_NAME("smpro-misc"),
>
> [Lee Jones]
> Misc is a Linuxisum which are not allowed in DT.
>
> What does this driver actually do?
>
> [Quan]
> This drivers is to report the boot progress to BMC and allow BMC to
> configure the Soc Power Limit of Ampere's Altra family processor.

That doesn't sound like it should be platform specific at all, but rather
a generic BMC interface. I see you already have the openbmc list on Cc,
so I assume the right people can see this. Presumably this is a BMC that
already runs on openbmc and can have a platform-independent interface
for doing this.

        Arnd
diff mbox series

Patch

diff --git a/drivers/mfd/smpro-mfd.c b/drivers/mfd/smpro-mfd.c
index a7cd64bf9eaa..5611dd30f8f4 100644
--- a/drivers/mfd/smpro-mfd.c
+++ b/drivers/mfd/smpro-mfd.c
@@ -28,6 +28,7 @@  static const struct regmap_config simple_word_regmap_config = {
 static const struct mfd_cell smpro_devs[] = {
 	MFD_CELL_NAME("smpro-hwmon"),
 	MFD_CELL_NAME("smpro-errmon"),
+	MFD_CELL_NAME("smpro-misc"),
 };
 
 static int smpro_mfd_probe(struct i2c_client *i2c)
diff --git a/drivers/misc/Kconfig b/drivers/misc/Kconfig
index 0cbd8a2561a7..df53cbf62931 100644
--- a/drivers/misc/Kconfig
+++ b/drivers/misc/Kconfig
@@ -183,6 +183,13 @@  config SMPRO_ERRMON
 	  If you say yes here you get support for error monitor function
 	  provides by Ampere Computing's SoC with SMpro processor.
 
+config SMPRO_MISC
+	tristate "Ampere Computing SMPro miscellaneous driver"
+	depends on MFD_SMPRO || COMPILE_TEST
+	help
+	  If you say yes here you get support for the miscellaleous function
+	  provides by Ampere Computing's SoC with SMpro processor.
+
 config CS5535_MFGPT
 	tristate "CS5535/CS5536 Geode Multi-Function General Purpose Timer (MFGPT) support"
 	depends on MFD_CS5535
diff --git a/drivers/misc/Makefile b/drivers/misc/Makefile
index 8ec9961b941b..bbfee81499de 100644
--- a/drivers/misc/Makefile
+++ b/drivers/misc/Makefile
@@ -24,6 +24,7 @@  obj-$(CONFIG_KGDB_TESTS)	+= kgdbts.o
 obj-$(CONFIG_SGI_XP)		+= sgi-xp/
 obj-$(CONFIG_SGI_GRU)		+= sgi-gru/
 obj-$(CONFIG_SMPRO_ERRMON)	+= smpro-errmon.o
+obj-$(CONFIG_SMPRO_MISC)	+= smpro-misc.o
 obj-$(CONFIG_CS5535_MFGPT)	+= cs5535-mfgpt.o
 obj-$(CONFIG_GEHC_ACHC)		+= gehc-achc.o
 obj-$(CONFIG_HP_ILO)		+= hpilo.o
diff --git a/drivers/misc/smpro-misc.c b/drivers/misc/smpro-misc.c
new file mode 100644
index 000000000000..6fe9d25ce31c
--- /dev/null
+++ b/drivers/misc/smpro-misc.c
@@ -0,0 +1,177 @@ 
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Ampere Computing SoC's SMpro Misc Driver
+ *
+ * Copyright (c) 2021, Ampere Computing LLC
+ */
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+/* Boot Stage/Progress Registers */
+#define BOOTSTAGE_SELECT	0xB0
+#define BOOTSTAGE_STATUS_LO	0xB1
+#define BOOTSTAGE_CUR_STAGE	0xB2
+#define BOOTSTAGE_STATUS_HI	0xB3
+
+/* SOC State Registers */
+#define SOC_POWER_LIMIT		0xE5
+
+/* Boot stages */
+enum {
+	BOOTSTAGE_SMPRO = 0,
+	BOOTSTAGE_PMPRO,
+	BOOTSTAGE_ATF_BL1,
+	BOOTSTAGE_DDR_INIT,
+	BOOTSTAGE_DDR_INIT_PROGRESS,
+	BOOTSTAGE_ATF_BL2,
+	BOOTSTAGE_ATF_BL31,
+	BOOTSTAGE_ATF_BL32,
+	BOOTSTAGE_UEFI,
+	BOOTSTAGE_OS,
+	BOOTSTAGE_MAX
+};
+
+struct smpro_misc {
+	struct regmap *regmap;
+};
+
+static int boot_progress_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	struct smpro_misc *misc = dev_get_drvdata(dev);
+	u32 boot_progress;
+	u8 current_stage;
+	u8 boot_status;
+	u8 boot_stage;
+	u32 select;
+	u32 reg_lo;
+	u32 reg;
+	int ret;
+
+	/* Read current boot stage */
+	ret = regmap_read(misc->regmap, BOOTSTAGE_CUR_STAGE, &reg);
+	if (ret)
+		return ret;
+
+	current_stage = reg & 0xff;
+
+	/* Read the boot progress */
+	ret = regmap_read(misc->regmap, BOOTSTAGE_SELECT, &select);
+	if (ret)
+		return ret;
+
+	boot_stage = (select >> 8) & 0xff;
+	boot_status = select & 0xff;
+
+	if (boot_stage > current_stage)
+		return -EINVAL;
+
+	ret = regmap_read(misc->regmap,	BOOTSTAGE_STATUS_LO, &reg_lo);
+	if (!ret)
+		ret = regmap_read(misc->regmap, BOOTSTAGE_STATUS_HI, &reg);
+	if (ret)
+		return ret;
+
+	boot_progress = swab16(reg) << 16 | swab16(reg_lo);
+
+	/* Tell firmware to provide next boot stage next time */
+	if (boot_stage < current_stage) {
+		ret = regmap_write(misc->regmap, BOOTSTAGE_SELECT, ((select & 0xff00) | 0x1));
+		if (ret)
+			return ret;
+	}
+
+	return snprintf(buf, PAGE_SIZE, "0x%02x 0x%02x 0x%08x\n",
+			boot_stage, boot_status, boot_progress);
+}
+
+static DEVICE_ATTR_RO(boot_progress);
+
+static int soc_power_limit_show(struct device *dev, struct device_attribute *da, char *buf)
+{
+	struct smpro_misc *misc = dev_get_drvdata(dev);
+	unsigned int value;
+	int ret;
+
+	ret = regmap_read(misc->regmap, SOC_POWER_LIMIT, &value);
+	if (ret)
+		return ret;
+
+	return snprintf(buf, PAGE_SIZE, "%d\n", value);
+}
+
+static int soc_power_limit_store(struct device *dev, struct device_attribute *da,
+				 const char *buf, size_t count)
+{
+	struct smpro_misc *misc = dev_get_drvdata(dev);
+	unsigned long val;
+	s32 ret;
+
+	ret = kstrtoul(buf, 0, &val);
+	if (ret)
+		return ret;
+
+	ret = regmap_write(misc->regmap, SOC_POWER_LIMIT, (unsigned int)val);
+	if (ret)
+		return -EPROTO;
+
+	return count;
+}
+
+static DEVICE_ATTR_RW(soc_power_limit);
+
+static struct attribute *smpro_misc_attrs[] = {
+	&dev_attr_boot_progress.attr,
+	&dev_attr_soc_power_limit.attr,
+	NULL
+};
+
+static const struct attribute_group smpro_misc_attr_group = {
+	.attrs = smpro_misc_attrs
+};
+
+static int smpro_misc_probe(struct platform_device *pdev)
+{
+	struct smpro_misc *misc;
+	int ret;
+
+	misc = devm_kzalloc(&pdev->dev, sizeof(struct smpro_misc), GFP_KERNEL);
+	if (!misc)
+		return -ENOMEM;
+
+	platform_set_drvdata(pdev, misc);
+
+	misc->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+	if (!misc->regmap)
+		return -ENODEV;
+
+	ret = sysfs_create_group(&pdev->dev.kobj, &smpro_misc_attr_group);
+	if (ret)
+		dev_err(&pdev->dev, "SMPro misc sysfs registration failed\n");
+
+	return 0;
+}
+
+static int smpro_misc_remove(struct platform_device *pdev)
+{
+	sysfs_remove_group(&pdev->dev.kobj, &smpro_misc_attr_group);
+	pr_info("SMPro misc sysfs entries removed");
+
+	return 0;
+}
+
+static struct platform_driver smpro_misc_driver = {
+	.probe		= smpro_misc_probe,
+	.remove		= smpro_misc_remove,
+	.driver = {
+		.name	= "smpro-misc",
+	},
+};
+
+module_platform_driver(smpro_misc_driver);
+
+MODULE_AUTHOR("Tung Nguyen <tungnguyen@os.amperecomputing.com>");
+MODULE_AUTHOR("Quan Nguyen <quan@os.amperecomputing.com>");
+MODULE_DESCRIPTION("Ampere Altra SMpro Misc driver");
+MODULE_LICENSE("GPL");