[Intel-gfx] [PATCH 1/1] drm/i915: Use GEN12 RPSTAT register

Dixit, Ashutosh ashutosh.dixit at intel.com
Wed Sep 28 01:47:28 UTC 2022


On Tue, 27 Sep 2022 04:35:29 -0700, Badal Nilawar wrote:
>
> From: Don Hiatt <don.hiatt at intel.com>
>
> On GEN12 and above use GEN12_RPSTAT register to get Current
> Actual Graphics Frequency of GT

I think even for the purposes of reviewing this it would be good to mention
in the commit message that:

a. GEN12_RPSTAT register doesn't require a forcewake to be read (it doesn't
   belong to a forcewake domain)
b. Will result in a 0 frequency if the GT is in RC6

Thanks.
--
Ashutosh

> v2:
>   - Fixed review comments(Ashutosh)
>   - Added function intel_rps_read_rpstat_fw to read RPSTAT without
>     forcewake, required especially for GEN6_RPSTAT1 (Ashutosh, Tvrtko)
>
> Cc: Don Hiatt <donhiatt at gmail.com>
> Cc: Andi Shyti <andi.shyti at intel.com>
> Signed-off-by: Don Hiatt <don.hiatt at intel.com>
> Signed-off-by: Badal Nilawar <badal.nilawar at intel.com>
> ---
>  drivers/gpu/drm/i915/gt/intel_gt_pm_debugfs.c |  2 +-
>  drivers/gpu/drm/i915/gt/intel_gt_regs.h       |  4 +++
>  drivers/gpu/drm/i915/gt/intel_rps.c           | 32 +++++++++++++++++--
>  drivers/gpu/drm/i915/gt/intel_rps.h           |  2 ++
>  drivers/gpu/drm/i915/i915_pmu.c               |  3 +-
>  5 files changed, 38 insertions(+), 5 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/gt/intel_gt_pm_debugfs.c b/drivers/gpu/drm/i915/gt/intel_gt_pm_debugfs.c
> index 10f680dbd7b6..b9b47052b26d 100644
> --- a/drivers/gpu/drm/i915/gt/intel_gt_pm_debugfs.c
> +++ b/drivers/gpu/drm/i915/gt/intel_gt_pm_debugfs.c
> @@ -380,7 +380,7 @@ void intel_gt_pm_frequency_dump(struct intel_gt *gt, struct drm_printer *p)
>		rpinclimit = intel_uncore_read(uncore, GEN6_RP_UP_THRESHOLD);
>		rpdeclimit = intel_uncore_read(uncore, GEN6_RP_DOWN_THRESHOLD);
>
> -		rpstat = intel_uncore_read(uncore, GEN6_RPSTAT1);
> +		rpstat = intel_rps_read_rpstat(rps);
>		rpcurupei = intel_uncore_read(uncore, GEN6_RP_CUR_UP_EI) & GEN6_CURICONT_MASK;
>		rpcurup = intel_uncore_read(uncore, GEN6_RP_CUR_UP) & GEN6_CURBSYTAVG_MASK;
>		rpprevup = intel_uncore_read(uncore, GEN6_RP_PREV_UP) & GEN6_CURBSYTAVG_MASK;
> diff --git a/drivers/gpu/drm/i915/gt/intel_gt_regs.h b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
> index 7f79bbf97828..1f1e90acc1ab 100644
> --- a/drivers/gpu/drm/i915/gt/intel_gt_regs.h
> +++ b/drivers/gpu/drm/i915/gt/intel_gt_regs.h
> @@ -1519,6 +1519,10 @@
>  #define VLV_RENDER_C0_COUNT			_MMIO(0x138118)
>  #define VLV_MEDIA_C0_COUNT			_MMIO(0x13811c)
>
> +#define GEN12_RPSTAT1				_MMIO(0x1381b4)
> +#define   GEN12_CAGF_SHIFT			11
> +#define   GEN12_CAGF_MASK			REG_GENMASK(19, 11)
> +
>  #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/gt/intel_rps.c b/drivers/gpu/drm/i915/gt/intel_rps.c
> index 17b40b625e31..5a15a630b1c6 100644
> --- a/drivers/gpu/drm/i915/gt/intel_rps.c
> +++ b/drivers/gpu/drm/i915/gt/intel_rps.c
> @@ -2068,12 +2068,40 @@ void intel_rps_sanitize(struct intel_rps *rps)
>		rps_disable_interrupts(rps);
>  }
>
> +u32 intel_rps_read_rpstat_fw(struct intel_rps *rps)
> +{
> +	struct drm_i915_private *i915 = rps_to_i915(rps);
> +	i915_reg_t rpstat;
> +
> +	if (GRAPHICS_VER(i915) >= 12)
> +		rpstat = GEN12_RPSTAT1;
> +	else
> +		rpstat = GEN6_RPSTAT1;
> +
> +	return intel_uncore_read_fw(rps_to_gt(rps)->uncore, rpstat);
> +}
> +
> +u32 intel_rps_read_rpstat(struct intel_rps *rps)
> +{
> +	struct drm_i915_private *i915 = rps_to_i915(rps);
> +	i915_reg_t rpstat;
> +
> +	if (GRAPHICS_VER(i915) >= 12)
> +		rpstat = GEN12_RPSTAT1;
> +	else
> +		rpstat = GEN6_RPSTAT1;
> +
> +	return intel_uncore_read(rps_to_gt(rps)->uncore, rpstat);
> +}
> +
>  u32 intel_rps_get_cagf(struct intel_rps *rps, u32 rpstat)
>  {
>	struct drm_i915_private *i915 = rps_to_i915(rps);
>	u32 cagf;
>
> -	if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915))
> +	if (GRAPHICS_VER(i915) >= 12)
> +		cagf = (rpstat & GEN12_CAGF_MASK) >> GEN12_CAGF_SHIFT;
> +	else if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915))
>		cagf = (rpstat >> 8) & 0xff;
>	else if (GRAPHICS_VER(i915) >= 9)
>		cagf = (rpstat & GEN9_CAGF_MASK) >> GEN9_CAGF_SHIFT;
> @@ -2099,7 +2127,7 @@ static u32 read_cagf(struct intel_rps *rps)
>		freq = vlv_punit_read(i915, PUNIT_REG_GPU_FREQ_STS);
>		vlv_punit_put(i915);
>	} else if (GRAPHICS_VER(i915) >= 6) {
> -		freq = intel_uncore_read(uncore, GEN6_RPSTAT1);
> +		freq = intel_rps_read_rpstat(rps);
>	} else {
>		freq = intel_uncore_read(uncore, MEMSTAT_ILK);
>	}
> diff --git a/drivers/gpu/drm/i915/gt/intel_rps.h b/drivers/gpu/drm/i915/gt/intel_rps.h
> index 4509dfdc52e0..76c8404d8416 100644
> --- a/drivers/gpu/drm/i915/gt/intel_rps.h
> +++ b/drivers/gpu/drm/i915/gt/intel_rps.h
> @@ -47,6 +47,8 @@ u32 intel_rps_get_rp1_frequency(struct intel_rps *rps);
>  u32 intel_rps_get_rpn_frequency(struct intel_rps *rps);
>  u32 intel_rps_read_punit_req(struct intel_rps *rps);
>  u32 intel_rps_read_punit_req_frequency(struct intel_rps *rps);
> +u32 intel_rps_read_rpstat(struct intel_rps *rps);
> +u32 intel_rps_read_rpstat_fw(struct intel_rps *rps);
>  void gen6_rps_get_freq_caps(struct intel_rps *rps, struct intel_rps_freq_caps *caps);
>  void intel_rps_raise_unslice(struct intel_rps *rps);
>  void intel_rps_lower_unslice(struct intel_rps *rps);
> diff --git a/drivers/gpu/drm/i915/i915_pmu.c b/drivers/gpu/drm/i915/i915_pmu.c
> index 958b37123bf1..67140a87182f 100644
> --- a/drivers/gpu/drm/i915/i915_pmu.c
> +++ b/drivers/gpu/drm/i915/i915_pmu.c
> @@ -371,7 +371,6 @@ static void
>  frequency_sample(struct intel_gt *gt, unsigned int period_ns)
>  {
>	struct drm_i915_private *i915 = gt->i915;
> -	struct intel_uncore *uncore = gt->uncore;
>	struct i915_pmu *pmu = &i915->pmu;
>	struct intel_rps *rps = &gt->rps;
>
> @@ -394,7 +393,7 @@ frequency_sample(struct intel_gt *gt, unsigned int period_ns)
>		 * case we assume the system is running at the intended
>		 * frequency. Fortunately, the read should rarely fail!
>		 */
> -		val = intel_uncore_read_fw(uncore, GEN6_RPSTAT1);
> +		val = intel_rps_read_rpstat_fw(rps);
>		if (val)
>			val = intel_rps_get_cagf(rps, val);
>		else
> --
> 2.25.1
>


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