On Wed, Jul 24, 2024 at 02:11:40PM +0530, Nilawar, Badal wrote:
>
>
> On 12-07-2024 17:53, Raag Jadav wrote:
> > Add hwmon support for fan1_input attribute, which will expose fan speed
> > in RPM. With this in place we can monitor fan speed using lm-sensors tool.
> >
> > $ sensors
> > i915-pci-0300
> > Adapter: PCI adapter
> > in0: 653.00 mV
> > fan1: 3833 RPM
> > power1: N/A (max = 43.00 W)
> > energy1: 32.02 kJ
> >
> > Signed-off-by: Raag Jadav <raag.jadav@xxxxxxxxx>
> > ---
> > drivers/gpu/drm/i915/gt/intel_gt_regs.h | 2 +
> > drivers/gpu/drm/i915/i915_hwmon.c | 71 +++++++++++++++++++++++++
> > 2 files changed, 73 insertions(+)
> >
> > diff --git a/drivers/gpu/drm/i915/gt/intel_gt_regs.h b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
> > index e42b3a5d4e63..407d8152755a 100644
> > --- a/drivers/gpu/drm/i915/gt/intel_gt_regs.h
> > +++ b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
> > @@ -1553,6 +1553,8 @@
> > #define VLV_RENDER_C0_COUNT _MMIO(0x138118)
> > #define VLV_MEDIA_C0_COUNT _MMIO(0x13811c)
> > +#define GEN12_PWM_FAN_SPEED _MMIO(0x138140)
> > +
> > #define GEN12_RPSTAT1 _MMIO(0x1381b4)
> > #define GEN12_VOLTAGE_MASK REG_GENMASK(10, 0)
> > #define GEN12_CAGF_MASK REG_GENMASK(19, 11)
> > diff --git a/drivers/gpu/drm/i915/i915_hwmon.c b/drivers/gpu/drm/i915/i915_hwmon.c
> > index 49db3e09826c..f829c7837d83 100644
> > --- a/drivers/gpu/drm/i915/i915_hwmon.c
> > +++ b/drivers/gpu/drm/i915/i915_hwmon.c
> > @@ -36,6 +36,7 @@ struct hwm_reg {
> > i915_reg_t pkg_rapl_limit;
> > i915_reg_t energy_status_all;
> > i915_reg_t energy_status_tile;
> > + i915_reg_t fan_speed;
> > };
> > struct hwm_energy_info {
> > @@ -43,11 +44,17 @@ struct hwm_energy_info {
> > long accum_energy; /* Accumulated energy for energy1_input */
> > };
> > +struct hwm_fan_info {
> > + u32 reg_val_prev;
> > + u32 time_prev;
> > +};
> > +
> > struct hwm_drvdata {
> > struct i915_hwmon *hwmon;
> > struct intel_uncore *uncore;
> > struct device *hwmon_dev;
> > struct hwm_energy_info ei; /* Energy info for energy1_input */
> > + struct hwm_fan_info fi; /* Fan info for fan1_input */
> > char name[12];
> > int gt_n;
> > bool reset_in_progress;
> > @@ -276,6 +283,7 @@ static const struct hwmon_channel_info * const hwm_info[] = {
> > HWMON_CHANNEL_INFO(power, HWMON_P_MAX | HWMON_P_RATED_MAX | HWMON_P_CRIT),
> > HWMON_CHANNEL_INFO(energy, HWMON_E_INPUT),
> > HWMON_CHANNEL_INFO(curr, HWMON_C_CRIT),
> > + HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT),
> > NULL
> > };
> > @@ -613,6 +621,55 @@ hwm_curr_write(struct hwm_drvdata *ddat, u32 attr, long val)
> > }
> > }
> > +static umode_t
> > +hwm_fan_is_visible(const struct hwm_drvdata *ddat, u32 attr)
> > +{
> > + struct i915_hwmon *hwmon = ddat->hwmon;
> > +
> > + switch (attr) {
> > + case hwmon_fan_input:
> > + return i915_mmio_reg_valid(hwmon->rg.fan_speed) ? 0444 : 0;
> > + default:
> > + return 0;
> > + }
> > +}
> > +
> > +static int
> > +hwm_fan_read(struct hwm_drvdata *ddat, u32 attr, long *val)
> > +{
> > + struct i915_hwmon *hwmon = ddat->hwmon;
> > + u32 reg_val, rotation, time, time_now;
> > + intel_wakeref_t wakeref;
> > +
> > + switch (attr) {
> > + case hwmon_fan_input:
> > + with_intel_runtime_pm(ddat->uncore->rpm, wakeref)
> Do we expect fan running when device is in D3? If not then we should use
> with_intel_runtime_pm_if_active here otherwise report fan speed 0.
Yes, it can be running depending on package temperature.
So better to rely on hardware value.
Raag
