From: Riana Tauro <riana.tauro@xxxxxxxxx> Use i915 HWMON subsystem to display current input voltage. v2: - Updated date and kernel version in feature description - Fixed review comments (Ashutosh) v3: Use macro HWMON_CHANNEL_INFO to define hwmon channel (Guenter) v4: - Fixed review comments (Ashutosh) - Use hwm_ prefix for static functions (Ashutosh) v5: Added unit of voltage as millivolts (Ashutosh) v6: KernelVersion: 6.2, Date: February 2023 in doc (Tvrtko) Cc: Guenter Roeck <linux@xxxxxxxxxxxx> Cc: Anshuman Gupta <anshuman.gupta@xxxxxxxxx> Signed-off-by: Riana Tauro <riana.tauro@xxxxxxxxx> Signed-off-by: Badal Nilawar <badal.nilawar@xxxxxxxxx> Acked-by: Guenter Roeck <linux@xxxxxxxxxxxx> Reviewed-by: Ashutosh Dixit <ashutosh.dixit@xxxxxxxxx> Reviewed-by: Anshuman Gupta <anshuman.gupta@xxxxxxxxx> --- .../ABI/testing/sysfs-driver-intel-i915-hwmon | 7 +++ drivers/gpu/drm/i915/gt/intel_gt_regs.h | 3 ++ drivers/gpu/drm/i915/i915_hwmon.c | 53 +++++++++++++++++++ 3 files changed, 63 insertions(+) create mode 100644 Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon diff --git a/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon b/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon new file mode 100644 index 000000000000..cd9554c1a4f8 --- /dev/null +++ b/Documentation/ABI/testing/sysfs-driver-intel-i915-hwmon @@ -0,0 +1,7 @@ +What: /sys/devices/.../hwmon/hwmon<i>/in0_input +Date: February 2023 +KernelVersion: 6.2 +Contact: dri-devel@xxxxxxxxxxxxxxxxxxxxx +Description: RO. Current Voltage in millivolt. + + Only supported for particular Intel i915 graphics platforms. diff --git a/drivers/gpu/drm/i915/gt/intel_gt_regs.h b/drivers/gpu/drm/i915/gt/intel_gt_regs.h index 7f79bbf97828..fcf5f9012852 100644 --- a/drivers/gpu/drm/i915/gt/intel_gt_regs.h +++ b/drivers/gpu/drm/i915/gt/intel_gt_regs.h @@ -1519,6 +1519,9 @@ #define VLV_RENDER_C0_COUNT _MMIO(0x138118) #define VLV_MEDIA_C0_COUNT _MMIO(0x13811c) +#define GEN12_RPSTAT1 _MMIO(0x1381b4) +#define GEN12_VOLTAGE_MASK REG_GENMASK(10, 0) + #define GEN11_GT_INTR_DW(x) _MMIO(0x190018 + ((x) * 4)) #define GEN11_CSME (31) #define GEN11_GUNIT (28) diff --git a/drivers/gpu/drm/i915/i915_hwmon.c b/drivers/gpu/drm/i915/i915_hwmon.c index 231552fda374..9fcff6a884ee 100644 --- a/drivers/gpu/drm/i915/i915_hwmon.c +++ b/drivers/gpu/drm/i915/i915_hwmon.c @@ -11,8 +11,16 @@ #include "i915_hwmon.h" #include "i915_reg.h" #include "intel_mchbar_regs.h" +#include "gt/intel_gt_regs.h" + +/* + * SF_* - scale factors for particular quantities according to hwmon spec. + * - voltage - millivolts + */ +#define SF_VOLTAGE 1000 struct hwm_reg { + i915_reg_t gt_perf_status; }; struct hwm_drvdata { @@ -29,14 +37,49 @@ struct i915_hwmon { }; static const struct hwmon_channel_info *hwm_info[] = { + HWMON_CHANNEL_INFO(in, HWMON_I_INPUT), NULL }; +static umode_t +hwm_in_is_visible(const struct hwm_drvdata *ddat, u32 attr) +{ + switch (attr) { + case hwmon_in_input: + return i915_mmio_reg_valid(ddat->hwmon->rg.gt_perf_status) ? 0444 : 0; + default: + return 0; + } +} + +static int +hwm_in_read(struct hwm_drvdata *ddat, u32 attr, long *val) +{ + struct i915_hwmon *hwmon = ddat->hwmon; + intel_wakeref_t wakeref; + u32 reg_value; + + switch (attr) { + case hwmon_in_input: + with_intel_runtime_pm(ddat->uncore->rpm, wakeref) + reg_value = intel_uncore_read(ddat->uncore, hwmon->rg.gt_perf_status); + /* HW register value in units of 2.5 millivolt */ + *val = DIV_ROUND_CLOSEST(REG_FIELD_GET(GEN12_VOLTAGE_MASK, reg_value) * 25, 10); + return 0; + default: + return -EOPNOTSUPP; + } +} + static umode_t hwm_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr, int channel) { + struct hwm_drvdata *ddat = (struct hwm_drvdata *)drvdata; + switch (type) { + case hwmon_in: + return hwm_in_is_visible(ddat, attr); default: return 0; } @@ -46,7 +89,11 @@ static int hwm_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int channel, long *val) { + struct hwm_drvdata *ddat = dev_get_drvdata(dev); + switch (type) { + case hwmon_in: + return hwm_in_read(ddat, attr, val); default: return -EOPNOTSUPP; } @@ -76,6 +123,12 @@ static const struct hwmon_chip_info hwm_chip_info = { static void hwm_get_preregistration_info(struct drm_i915_private *i915) { + struct i915_hwmon *hwmon = i915->hwmon; + + if (IS_DG1(i915) || IS_DG2(i915)) + hwmon->rg.gt_perf_status = GEN12_RPSTAT1; + else + hwmon->rg.gt_perf_status = INVALID_MMIO_REG; } void i915_hwmon_register(struct drm_i915_private *i915) -- 2.25.1