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

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

On 9/29/21 9:20 PM, Ville Syrjälä wrote:
> On Wed, Sep 29, 2021 at 08:50:12PM +0300, Gwan-gyeong Mun wrote:
> > 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@xxxxxxxxx>
> > > Signed-off-by: José Roberto de Souza <jose.souza@xxxxxxxxx>
> > > ---
> > >    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.
>
> Cursor can have negative coordinates as it's hardware that will do the
> clipping for us.
Yes, you are right, thanks for pointing out it. The cursor plane's 
CUR_POS register has X and Y Position Sign bits.

Reviewed-by: Gwan-gyeong Mun <gwan-gyeong.mun@xxxxxxxxx>
> > 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;