Re: [Intel-gfx] [PATCH 4/7] drm/i915/display/psr: Handle plane restrictions at every page flip

[Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>]

On 9/23/21 10:46 PM, José Roberto de Souza wrote:
> PSR2 selective is not supported over rotated and scaled planes.
> We had the rotation check in intel_psr2_sel_fetch_config_valid()
> but that code path is only execute when a modeset is needed and
> change those plane parameters do not require a modeset.
> 
> Also need to check those restricions in the second
> for_each_oldnew_intel_plane_in_state() loop because the state could
> only have a plane that is not affected by those restricitons but
> the damaged area intersect with planes that has those restrictions,
> so a full plane fetch is required.
> 
> BSpec: 55229
> Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
> Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
> ---
>   drivers/gpu/drm/i915/display/intel_psr.c | 45 ++++++++++++++----------
>   1 file changed, 26 insertions(+), 19 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_psr.c b/drivers/gpu/drm/i915/display/intel_psr.c
> index 1cc4130dec7b1..356e0e96abf4e 100644
> --- a/drivers/gpu/drm/i915/display/intel_psr.c
> +++ b/drivers/gpu/drm/i915/display/intel_psr.c
> @@ -720,11 +720,7 @@ tgl_dc3co_exitline_compute_config(struct intel_dp *intel_dp,
>   static bool intel_psr2_sel_fetch_config_valid(struct intel_dp *intel_dp,
>   					      struct intel_crtc_state *crtc_state)
>   {
> -	struct intel_atomic_state *state = to_intel_atomic_state(crtc_state->uapi.state);
>   	struct drm_i915_private *dev_priv = dp_to_i915(intel_dp);
> -	struct intel_plane_state *plane_state;
> -	struct intel_plane *plane;
> -	int i;
>   
>   	if (!dev_priv->params.enable_psr2_sel_fetch &&
>   	    intel_dp->psr.debug != I915_PSR_DEBUG_ENABLE_SEL_FETCH) {
> @@ -739,14 +735,6 @@ static bool intel_psr2_sel_fetch_config_valid(struct intel_dp *intel_dp,
>   		return false;
>   	}
>   
> -	for_each_new_intel_plane_in_state(state, plane, plane_state, i) {
> -		if (plane_state->uapi.rotation != DRM_MODE_ROTATE_0) {
> -			drm_dbg_kms(&dev_priv->drm,
> -				    "PSR2 sel fetch not enabled, plane rotated\n");
> -			return false;
> -		}
> -	}
> -
>   	/* Wa_14010254185 Wa_14010103792 */
>   	if (IS_TGL_DISPLAY_STEP(dev_priv, STEP_A0, STEP_C0)) {
>   		drm_dbg_kms(&dev_priv->drm,
> @@ -1586,6 +1574,26 @@ static void cursor_area_workaround(const struct intel_plane_state *new_plane_sta
>   	clip_area_update(pipe_clip, damaged_area);
>   }
>   
> +/*
> + * TODO: Not clear how to handle planes with negative position,
> + * also planes are not updated if they have a negative X
> + * position so for now doing a full update in this cases
> + *
> + * Plane scaling and rotation is not supported by selective fetch and both
> + * properties can change without a modeset, so need to be check at every
> + * atomic commmit.
> + */
> +static bool psr2_sel_fetch_plane_state_supported(const struct intel_plane_state *plane_state)
> +{
> +	if (plane_state->uapi.dst.y1 < 0 ||
> +	    plane_state->uapi.dst.x1 < 0 ||
intel_atomic_plane_check_clipping() function makes 
plane_state->uapi.dst.x1 and plane_state->uapi.dst.y1 non-negative 
values, so there is no need to deal with negative positions here.

And the rest of the changes look good to me.
> +	    plane_state->scaler_id >= 0 ||
> +	    plane_state->uapi.rotation != DRM_MODE_ROTATE_0)
> +		return false;
> +
> +	return true;
> +}
> +
>   int intel_psr2_sel_fetch_update(struct intel_atomic_state *state,
>   				struct intel_crtc *crtc)
>   {
> @@ -1618,13 +1626,7 @@ int intel_psr2_sel_fetch_update(struct intel_atomic_state *state,
>   		    !old_plane_state->uapi.visible)
>   			continue;
>   
> -		/*
> -		 * TODO: Not clear how to handle planes with negative position,
> -		 * also planes are not updated if they have a negative X
> -		 * position so for now doing a full update in this cases
> -		 */
> -		if (new_plane_state->uapi.dst.y1 < 0 ||
> -		    new_plane_state->uapi.dst.x1 < 0) {
> +		if (!psr2_sel_fetch_plane_state_supported(new_plane_state)) {
>   			full_update = true;
>   			break;
>   		}
> @@ -1703,6 +1705,11 @@ int intel_psr2_sel_fetch_update(struct intel_atomic_state *state,
>   		if (!drm_rect_intersect(&inter, &new_plane_state->uapi.dst))
>   			continue;
>   
> +		if (!psr2_sel_fetch_plane_state_supported(new_plane_state)) {
> +			full_update = true;
> +			break;
> +		}
> +
>   		sel_fetch_area = &new_plane_state->psr2_sel_fetch_area;
>   		sel_fetch_area->y1 = inter.y1 - new_plane_state->uapi.dst.y1;
>   		sel_fetch_area->y2 = inter.y2 - new_plane_state->uapi.dst.y1;
>