diff mbox series

[1/7] drm/i915/hwmon: Add HWMON infrastructure

Message ID 20220923195643.2376927-2-badal.nilawar@intel.com (mailing list archive)
State New, archived
Headers show
Series drm/i915: Add HWMON support | expand

Commit Message

Nilawar, Badal Sept. 23, 2022, 7:56 p.m. UTC 
From: Dale B Stimson <dale.b.stimson@intel.com>

The i915 HWMON module will be used to expose voltage, power and energy
values for dGfx. Here we set up i915 hwmon infrastructure including i915
hwmon registration, basic data structures and functions.

v2:
  - Create HWMON infra patch (Ashutosh)
  - Fixed review comments (Jani)
  - Remove "select HWMON" from i915/Kconfig (Jani)
v3: Use hwm_ prefix for static functions (Ashutosh)
v4: s/#ifdef CONFIG_HWMON/#if IS_REACHABLE(CONFIG_HWMON)/ since the former
    doesn't work if hwmon is compiled as a module (Guenter)
v5: Fixed review comments (Jani)
v6: s/kzalloc/devm_kzalloc/ (Andi)

Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Dale B Stimson <dale.b.stimson@intel.com>
Signed-off-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Signed-off-by: Riana Tauro <riana.tauro@intel.com>
Signed-off-by: Badal Nilawar <badal.nilawar@intel.com>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: Ashutosh Dixit <ashutosh.dixit@intel.com>
Reviewed-by: Anshuman Gupta <anshuman.gupta@intel.com>
---
 drivers/gpu/drm/i915/Makefile      |   3 +
 drivers/gpu/drm/i915/i915_driver.c |   5 ++
 drivers/gpu/drm/i915/i915_drv.h    |   2 +
 drivers/gpu/drm/i915/i915_hwmon.c  | 131 +++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_hwmon.h  |  20 +++++
 5 files changed, 161 insertions(+)
 create mode 100644 drivers/gpu/drm/i915/i915_hwmon.c
 create mode 100644 drivers/gpu/drm/i915/i915_hwmon.h

Comments

Dixit, Ashutosh Sept. 24, 2022, 3:54 a.m. UTC | #1 
On Fri, 23 Sep 2022 12:56:37 -0700, Badal Nilawar wrote:
>

Hi Badal,

Let me add this comment on the latest version so we don't forget about it:

> +void i915_hwmon_register(struct drm_i915_private *i915)
> +{
> +	struct device *dev = i915->drm.dev;
> +	struct i915_hwmon *hwmon;
> +	struct device *hwmon_dev;
> +	struct hwm_drvdata *ddat;
> +
> +	/* hwmon is available only for dGfx */
> +	if (!IS_DGFX(i915))
> +		return;
> +
> +	hwmon = devm_kzalloc(dev, sizeof(*hwmon), GFP_KERNEL);

If we are using devm_kzalloc we might as well replace all the
hwmon_device_register_with_info's (in Patch 1 and 7) with
devm_hwmon_device_register_with_info and then i915_hwmon_unregister is just
this:

void i915_hwmon_unregister(struct drm_i915_private *i915)
{
        fetch_and_zero(&i915->hwmon);
}

Even the above statement is probably not needed but might as well retain it
for sanity. So this is a simple change.

Thanks.
--
Ashutosh
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/Makefile b/drivers/gpu/drm/i915/Makefile
index a26edcdadc21..66a6023e61a6 100644
--- a/drivers/gpu/drm/i915/Makefile
+++ b/drivers/gpu/drm/i915/Makefile
@@ -209,6 +209,9 @@  i915-y += gt/uc/intel_uc.o \
 # graphics system controller (GSC) support
 i915-y += gt/intel_gsc.o
 
+# graphics hardware monitoring (HWMON) support
+i915-$(CONFIG_HWMON) += i915_hwmon.o
+
 # modesetting core code
 i915-y += \
 	display/hsw_ips.o \
diff --git a/drivers/gpu/drm/i915/i915_driver.c b/drivers/gpu/drm/i915/i915_driver.c
index 9d1fc2477f80..ae0414037625 100644
--- a/drivers/gpu/drm/i915/i915_driver.c
+++ b/drivers/gpu/drm/i915/i915_driver.c
@@ -81,6 +81,7 @@ 
 #include "i915_drm_client.h"
 #include "i915_drv.h"
 #include "i915_getparam.h"
+#include "i915_hwmon.h"
 #include "i915_ioc32.h"
 #include "i915_ioctl.h"
 #include "i915_irq.h"
@@ -763,6 +764,8 @@  static void i915_driver_register(struct drm_i915_private *dev_priv)
 	for_each_gt(gt, dev_priv, i)
 		intel_gt_driver_register(gt);
 
+	i915_hwmon_register(dev_priv);
+
 	intel_display_driver_register(dev_priv);
 
 	intel_power_domains_enable(dev_priv);
@@ -795,6 +798,8 @@  static void i915_driver_unregister(struct drm_i915_private *dev_priv)
 	for_each_gt(gt, dev_priv, i)
 		intel_gt_driver_unregister(gt);
 
+	i915_hwmon_unregister(dev_priv);
+
 	i915_perf_unregister(dev_priv);
 	i915_pmu_unregister(dev_priv);
 
diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h
index 134fc1621821..3197aa9d35d6 100644
--- a/drivers/gpu/drm/i915/i915_drv.h
+++ b/drivers/gpu/drm/i915/i915_drv.h
@@ -350,6 +350,8 @@  struct drm_i915_private {
 
 	struct i915_perf perf;
 
+	struct i915_hwmon *hwmon;
+
 	/* Abstract the submission mechanism (legacy ringbuffer or execlists) away */
 	struct intel_gt gt0;
 
diff --git a/drivers/gpu/drm/i915/i915_hwmon.c b/drivers/gpu/drm/i915/i915_hwmon.c
new file mode 100644
index 000000000000..2847ca4e1a77
--- /dev/null
+++ b/drivers/gpu/drm/i915/i915_hwmon.c
@@ -0,0 +1,131 @@ 
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright © 2022 Intel Corporation
+ */
+
+#include <linux/hwmon.h>
+#include <linux/hwmon-sysfs.h>
+#include <linux/types.h>
+
+#include "i915_drv.h"
+#include "i915_hwmon.h"
+#include "i915_reg.h"
+#include "intel_mchbar_regs.h"
+
+struct hwm_reg {
+};
+
+struct hwm_drvdata {
+	struct i915_hwmon *hwmon;
+	struct intel_uncore *uncore;
+	struct device *hwmon_dev;
+	char name[12];
+};
+
+struct i915_hwmon {
+	struct hwm_drvdata ddat;
+	struct mutex hwmon_lock;		/* counter overflow logic and rmw */
+	struct hwm_reg rg;
+};
+
+static const struct hwmon_channel_info *hwm_info[] = {
+	NULL
+};
+
+static umode_t
+hwm_is_visible(const void *drvdata, enum hwmon_sensor_types type,
+	       u32 attr, int channel)
+{
+	switch (type) {
+	default:
+		return 0;
+	}
+}
+
+static int
+hwm_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
+	 int channel, long *val)
+{
+	switch (type) {
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static int
+hwm_write(struct device *dev, enum hwmon_sensor_types type, u32 attr,
+	  int channel, long val)
+{
+	switch (type) {
+	default:
+		return -EOPNOTSUPP;
+	}
+}
+
+static const struct hwmon_ops hwm_ops = {
+	.is_visible = hwm_is_visible,
+	.read = hwm_read,
+	.write = hwm_write,
+};
+
+static const struct hwmon_chip_info hwm_chip_info = {
+	.ops = &hwm_ops,
+	.info = hwm_info,
+};
+
+static void
+hwm_get_preregistration_info(struct drm_i915_private *i915)
+{
+}
+
+void i915_hwmon_register(struct drm_i915_private *i915)
+{
+	struct device *dev = i915->drm.dev;
+	struct i915_hwmon *hwmon;
+	struct device *hwmon_dev;
+	struct hwm_drvdata *ddat;
+
+	/* hwmon is available only for dGfx */
+	if (!IS_DGFX(i915))
+		return;
+
+	hwmon = devm_kzalloc(dev, sizeof(*hwmon), GFP_KERNEL);
+	if (!hwmon)
+		return;
+
+	i915->hwmon = hwmon;
+	mutex_init(&hwmon->hwmon_lock);
+	ddat = &hwmon->ddat;
+
+	ddat->hwmon = hwmon;
+	ddat->uncore = &i915->uncore;
+	snprintf(ddat->name, sizeof(ddat->name), "i915");
+
+	hwm_get_preregistration_info(i915);
+
+	/*  hwmon_dev points to device hwmon<i> */
+	hwmon_dev = hwmon_device_register_with_info(dev, ddat->name,
+						    ddat,
+						    &hwm_chip_info,
+						    NULL);
+	if (IS_ERR(hwmon_dev)) {
+		i915->hwmon = NULL;
+		return;
+	}
+
+	ddat->hwmon_dev = hwmon_dev;
+}
+
+void i915_hwmon_unregister(struct drm_i915_private *i915)
+{
+	struct i915_hwmon *hwmon;
+	struct hwm_drvdata *ddat;
+
+	hwmon = fetch_and_zero(&i915->hwmon);
+	if (!hwmon)
+		return;
+
+	ddat = &hwmon->ddat;
+	if (ddat->hwmon_dev)
+		hwmon_device_unregister(ddat->hwmon_dev);
+}
diff --git a/drivers/gpu/drm/i915/i915_hwmon.h b/drivers/gpu/drm/i915/i915_hwmon.h
new file mode 100644
index 000000000000..7ca9cf2c34c9
--- /dev/null
+++ b/drivers/gpu/drm/i915/i915_hwmon.h
@@ -0,0 +1,20 @@ 
+/* SPDX-License-Identifier: MIT */
+
+/*
+ * Copyright © 2022 Intel Corporation
+ */
+
+#ifndef __I915_HWMON_H__
+#define __I915_HWMON_H__
+
+struct drm_i915_private;
+
+#if IS_REACHABLE(CONFIG_HWMON)
+void i915_hwmon_register(struct drm_i915_private *i915);
+void i915_hwmon_unregister(struct drm_i915_private *i915);
+#else
+static inline void i915_hwmon_register(struct drm_i915_private *i915) { };
+static inline void i915_hwmon_unregister(struct drm_i915_private *i915) { };
+#endif
+
+#endif /* __I915_HWMON_H__ */