drm/i915/display/psr: Use plane damage clips to calculate damaged area

Now using plane damage clips property to calcualte the damaged area.
Selective fetch only supports one region to be fetched so software
needs to calculate a bounding box around all damage clips.

Now that we are not complete fetching each plane, there is another
loop needed as all the plane areas that intersect with the pipe
damaged area needs to be fetched from memory so the complete blending
of all planes can happen.

v2:
- do not shifting new_plane_state->uapi.dst only src is in 16.16 format

v4:
- setting plane selective fetch area using the whole pipe damage area
- mark the whole plane area damaged if plane visibility or alpha
changed

v5:
- taking in consideration src.y1 in the damage coordinates
- adding to the pipe damaged area planes that were visible but are
invisible in the new state

v6:
- consider old state plane coordinates when visibility changes or it
moved to calculate damaged area
- remove from damaged area the portion not in src clip

v7:
- intersec every damage clip with src to minimize damaged area

v8:
- adjust pipe_damaged area to 4 lines grouping
- adjust calculation now that is understood that uapi.src is the
framebuffer coordinates that plane will start to fetch from

v9:
- Only add plane dst or src to damaged_area if visible
- Early skip plane damage calculation if it was not visible in old and
new state

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Reviewed-by: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210104205654.238928-2-jose.souza@intel.com

drivers/gpu/drm/i915/display/intel_psr.c

@@ -1242,9 +1242,11 @@ static void psr2_man_trk_ctl_calc(struct intel_crtc_state *crtc_state,
 	if (clip->y1 == -1)
 		goto exit;
 
+	drm_WARN_ON(crtc_state->uapi.crtc->dev, clip->y1 % 4 || clip->y2 % 4);
+
 	val |= PSR2_MAN_TRK_CTL_SF_PARTIAL_FRAME_UPDATE;
 	val |= PSR2_MAN_TRK_CTL_SU_REGION_START_ADDR(clip->y1 / 4 + 1);
-	val |= PSR2_MAN_TRK_CTL_SU_REGION_END_ADDR(DIV_ROUND_UP(clip->y2, 4) + 1);
+	val |= PSR2_MAN_TRK_CTL_SU_REGION_END_ADDR(clip->y2 / 4 + 1);
 exit:
 	crtc_state->psr2_man_track_ctl = val;
 }
@@ -1269,8 +1271,8 @@ int intel_psr2_sel_fetch_update(struct intel_atomic_state *state,
 				struct intel_crtc *crtc)
 {
 	struct intel_crtc_state *crtc_state = intel_atomic_get_new_crtc_state(state, crtc);
+	struct drm_rect pipe_clip = { .x1 = 0, .y1 = -1, .x2 = INT_MAX, .y2 = -1 };
 	struct intel_plane_state *new_plane_state, *old_plane_state;
-	struct drm_rect pipe_clip = { .y1 = -1 };
 	struct intel_plane *plane;
 	bool full_update = false;
 	int i, ret;
@@ -1282,13 +1284,25 @@ int intel_psr2_sel_fetch_update(struct intel_atomic_state *state,
 	if (ret)
 		return ret;
 
+	/*
+	 * Calculate minimal selective fetch area of each plane and calculate
+	 * the pipe damaged area.
+	 * In the next loop the plane selective fetch area will actually be set
+	 * using whole pipe damaged area.
+	 */
 	for_each_oldnew_intel_plane_in_state(state, plane, old_plane_state,
 					     new_plane_state, i) {
-		struct drm_rect *sel_fetch_area, temp;
+		struct drm_rect src, damaged_area = { .y1 = -1 };
+		struct drm_mode_rect *damaged_clips;
+		u32 num_clips, j;
 
 		if (new_plane_state->uapi.crtc != crtc_state->uapi.crtc)
 			continue;
 
+		if (!new_plane_state->uapi.visible &&
+		    !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
@@ -1300,23 +1314,94 @@ int intel_psr2_sel_fetch_update(struct intel_atomic_state *state,
 			break;
 		}
 
-		if (!new_plane_state->uapi.visible)
-			continue;
+		num_clips = drm_plane_get_damage_clips_count(&new_plane_state->uapi);
 
 		/*
-		 * For now doing a selective fetch in the whole plane area,
-		 * optimizations will come in the future.
+		 * If visibility or plane moved, mark the whole plane area as
+		 * damaged as it needs to be complete redraw in the new and old
+		 * position.
 		 */
-		sel_fetch_area = &new_plane_state->psr2_sel_fetch_area;
-		sel_fetch_area->y1 = new_plane_state->uapi.src.y1 >> 16;
-		sel_fetch_area->y2 = new_plane_state->uapi.src.y2 >> 16;
+		if (new_plane_state->uapi.visible != old_plane_state->uapi.visible ||
+		    !drm_rect_equals(&new_plane_state->uapi.dst,
+				     &old_plane_state->uapi.dst)) {
+			if (old_plane_state->uapi.visible) {
+				damaged_area.y1 = old_plane_state->uapi.dst.y1;
+				damaged_area.y2 = old_plane_state->uapi.dst.y2;
+				clip_area_update(&pipe_clip, &damaged_area);
+			}
+
+			if (new_plane_state->uapi.visible) {
+				damaged_area.y1 = new_plane_state->uapi.dst.y1;
+				damaged_area.y2 = new_plane_state->uapi.dst.y2;
+				clip_area_update(&pipe_clip, &damaged_area);
+			}
+			continue;
+		} else if (new_plane_state->uapi.alpha != old_plane_state->uapi.alpha ||
+			   (!num_clips &&
+			    new_plane_state->uapi.fb != old_plane_state->uapi.fb)) {
+			/*
+			 * If the plane don't have damaged areas but the
+			 * framebuffer changed or alpha changed, mark the whole
+			 * plane area as damaged.
+			 */
+			damaged_area.y1 = new_plane_state->uapi.dst.y1;
+			damaged_area.y2 = new_plane_state->uapi.dst.y2;
+			clip_area_update(&pipe_clip, &damaged_area);
+			continue;
+		}
+
+		drm_rect_fp_to_int(&src, &new_plane_state->uapi.src);
+		damaged_clips = drm_plane_get_damage_clips(&new_plane_state->uapi);
+
+		for (j = 0; j < num_clips; j++) {
+			struct drm_rect clip;
+
+			clip.x1 = damaged_clips[j].x1;
+			clip.y1 = damaged_clips[j].y1;
+			clip.x2 = damaged_clips[j].x2;
+			clip.y2 = damaged_clips[j].y2;
+			if (drm_rect_intersect(&clip, &src))
+				clip_area_update(&damaged_area, &clip);
+		}
 
-		temp = *sel_fetch_area;
-		temp.y1 += new_plane_state->uapi.dst.y1;
-		temp.y2 += new_plane_state->uapi.dst.y2;
-		clip_area_update(&pipe_clip, &temp);
+		if (damaged_area.y1 == -1)
+			continue;
+
+		damaged_area.y1 += new_plane_state->uapi.dst.y1 - src.y1;
+		damaged_area.y2 += new_plane_state->uapi.dst.y1 - src.y1;
+		clip_area_update(&pipe_clip, &damaged_area);
+	}
+
+	if (full_update)
+		goto skip_sel_fetch_set_loop;
+
+	/* It must be aligned to 4 lines */
+	pipe_clip.y1 -= pipe_clip.y1 % 4;
+	if (pipe_clip.y2 % 4)
+		pipe_clip.y2 = ((pipe_clip.y2 / 4) + 1) * 4;
+
+	/*
+	 * Now that we have the pipe damaged area check if it intersect with
+	 * every plane, if it does set the plane selective fetch area.
+	 */
+	for_each_oldnew_intel_plane_in_state(state, plane, old_plane_state,
+					     new_plane_state, i) {
+		struct drm_rect *sel_fetch_area, inter;
+
+		if (new_plane_state->uapi.crtc != crtc_state->uapi.crtc ||
+		    !new_plane_state->uapi.visible)
+			continue;
+
+		inter = pipe_clip;
+		if (!drm_rect_intersect(&inter, &new_plane_state->uapi.dst))
+			continue;
+
+		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;
 	}
 
+skip_sel_fetch_set_loop:
 	psr2_man_trk_ctl_calc(crtc_state, &pipe_clip, full_update);
 	return 0;
 }