[PATCH 03/15] drm/i915/guc/slpc: Gate Host RPS when SLPC is enabled

[Matthew Brost]

On Mon, Jul 26, 2021 at 12:07:48PM -0700, Vinay Belgaumkar wrote:
> Also ensure uc_init is called before we initialize RPS so that we
> can check for SLPC support. We do not need to enable up/down
> interrupts when SLPC is enabled. However, we still need the ARAT
> interrupt, which will be enabled separately later.
>

Do we not need a check for rps_uses_slpc in intel_rps_enable? I guessing
there is a reason why we don't but can't seem to figure that out.

Matt

> Signed-off-by: Vinay Belgaumkar <vinay.belgaumkar at intel.com>
> Signed-off-by: Sundaresan Sujaritha <sujaritha.sundaresan at intel.com>
> ---
>  drivers/gpu/drm/i915/gt/intel_gt.c  |  2 +-
>  drivers/gpu/drm/i915/gt/intel_rps.c | 20 ++++++++++++++++++++
>  2 files changed, 21 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/i915/gt/intel_gt.c b/drivers/gpu/drm/i915/gt/intel_gt.c
> index a64aa43f7cd9..04dd69bcf6cb 100644
> --- a/drivers/gpu/drm/i915/gt/intel_gt.c
> +++ b/drivers/gpu/drm/i915/gt/intel_gt.c
> @@ -41,8 +41,8 @@ void intel_gt_init_early(struct intel_gt *gt, struct drm_i915_private *i915)
>  	intel_gt_init_timelines(gt);
>  	intel_gt_pm_init_early(gt);
>  
> -	intel_rps_init_early(&gt->rps);
>  	intel_uc_init_early(&gt->uc);
> +	intel_rps_init_early(&gt->rps);
>  }
>  
>  int intel_gt_probe_lmem(struct intel_gt *gt)
> diff --git a/drivers/gpu/drm/i915/gt/intel_rps.c b/drivers/gpu/drm/i915/gt/intel_rps.c
> index 0c8e7f2b06f0..e858eeb2c59d 100644
> --- a/drivers/gpu/drm/i915/gt/intel_rps.c
> +++ b/drivers/gpu/drm/i915/gt/intel_rps.c
> @@ -37,6 +37,13 @@ static struct intel_uncore *rps_to_uncore(struct intel_rps *rps)
>  	return rps_to_gt(rps)->uncore;
>  }
>  
> +static bool rps_uses_slpc(struct intel_rps *rps)
> +{
> +	struct intel_gt *gt = rps_to_gt(rps);
> +
> +	return intel_uc_uses_guc_slpc(&gt->uc);
> +}
> +
>  static u32 rps_pm_sanitize_mask(struct intel_rps *rps, u32 mask)
>  {
>  	return mask & ~rps->pm_intrmsk_mbz;
> @@ -167,6 +174,8 @@ static void rps_enable_interrupts(struct intel_rps *rps)
>  {
>  	struct intel_gt *gt = rps_to_gt(rps);
>  
> +	GEM_BUG_ON(rps_uses_slpc(rps));
> +
>  	GT_TRACE(gt, "interrupts:on rps->pm_events: %x, rps_pm_mask:%x\n",
>  		 rps->pm_events, rps_pm_mask(rps, rps->last_freq));
>  
> @@ -771,6 +780,8 @@ static int gen6_rps_set(struct intel_rps *rps, u8 val)
>  	struct drm_i915_private *i915 = rps_to_i915(rps);
>  	u32 swreq;
>  
> +	GEM_BUG_ON(rps_uses_slpc(rps));
> +
>  	if (GRAPHICS_VER(i915) >= 9)
>  		swreq = GEN9_FREQUENCY(val);
>  	else if (IS_HASWELL(i915) || IS_BROADWELL(i915))
> @@ -861,6 +872,9 @@ void intel_rps_park(struct intel_rps *rps)
>  {
>  	int adj;
>  
> +	if (!intel_rps_is_enabled(rps))
> +		return;
> +
>  	GEM_BUG_ON(atomic_read(&rps->num_waiters));
>  
>  	if (!intel_rps_clear_active(rps))
> @@ -1829,6 +1843,9 @@ void intel_rps_init(struct intel_rps *rps)
>  {
>  	struct drm_i915_private *i915 = rps_to_i915(rps);
>  
> +	if (rps_uses_slpc(rps))
> +		return;
> +
>  	if (IS_CHERRYVIEW(i915))
>  		chv_rps_init(rps);
>  	else if (IS_VALLEYVIEW(i915))
> @@ -1885,6 +1902,9 @@ void intel_rps_init(struct intel_rps *rps)
>  
>  void intel_rps_sanitize(struct intel_rps *rps)
>  {
> +	if (rps_uses_slpc(rps))
> +		return;
> +
>  	if (GRAPHICS_VER(rps_to_i915(rps)) >= 6)
>  		rps_disable_interrupts(rps);
>  }
> -- 
> 2.25.0
>