disp: msm: sde: add cache hints support in fb

Add a cache_flag in msm_fb object to store the system cache state hints.
Writeback connector will store cache write hints if system cache write
is enabled while HW is writing into this buffer. Plane in the primary
display path, in a 2-pass composition strategy will use this cache hints
to enable the display HW to use system cache for reading the pixel data
from this buffer.

Change-Id: Iff92a453a36d4a60b5a0162832eebd5e8739b5c3
Signed-off-by: Veera Sundaram Sankaran <veeras@codeaurora.org>

msm/sde/sde_plane.c

@@ -2782,32 +2782,44 @@ void sde_plane_set_error(struct drm_plane *plane, bool error)
 static void _sde_plane_sspp_setup_sys_cache(struct sde_plane *psde,
 		struct sde_plane_state *pstate)
 {
+	struct drm_plane_state *state = psde->base.state;
 	struct sde_sc_cfg *sc_cfg = psde->catalog->sc_cfg;
 	struct sde_hw_pipe_sc_cfg *cfg = &pstate->sc_cfg;
 	bool prev_rd_en = cfg->rd_en;
+	u32 fb_cache_flag, fb_cache_type;
 
-	if (!sc_cfg[SDE_SYS_CACHE_DISP].has_sys_cache)
-		return;
+	msm_framebuffer_get_cache_hint(state->fb, &fb_cache_flag, &fb_cache_type);
 
 	cfg->rd_en = false;
 	cfg->rd_scid = 0x0;
 	cfg->flags = SYS_CACHE_EN_FLAG | SYS_CACHE_SCID;
 	cfg->type = SDE_SYS_CACHE_NONE;
 
-	if ((pstate->static_cache_state == CACHE_STATE_FRAME_WRITE)
-			|| (pstate->static_cache_state == CACHE_STATE_FRAME_READ)) {
+	if ((sc_cfg[SDE_SYS_CACHE_DISP].has_sys_cache)
+			&& ((pstate->static_cache_state == CACHE_STATE_FRAME_WRITE)
+				|| (pstate->static_cache_state == CACHE_STATE_FRAME_READ))) {
 		cfg->rd_en = true;
 		cfg->rd_scid = sc_cfg[SDE_SYS_CACHE_DISP].llcc_scid;
 		cfg->rd_noallocate = (pstate->static_cache_state == CACHE_STATE_FRAME_READ);
 		cfg->flags |= SYS_CACHE_NO_ALLOC;
 		cfg->type = SDE_SYS_CACHE_DISP;
+
+	} else if ((sc_cfg[fb_cache_type].has_sys_cache)
+			&& (fb_cache_flag & MSM_FB_CACHE_WRITE_EN)) {
+		cfg->rd_en = true;
+		cfg->rd_scid = sc_cfg[fb_cache_type].llcc_scid;
+		cfg->rd_noallocate = true;
+		cfg->flags |= SYS_CACHE_NO_ALLOC;
+		cfg->type = fb_cache_type;
+
+		msm_framebuffer_set_cache_hint(state->fb, MSM_FB_CACHE_READ_EN, fb_cache_type);
 	}
 
 	if (!cfg->rd_en && !prev_rd_en)
 		return;
 
-	SDE_EVT32(DRMID(&psde->base), cfg->rd_scid, cfg->rd_en, cfg->rd_noallocate, cfg->flags);
-
+	SDE_EVT32(DRMID(&psde->base), cfg->rd_scid, cfg->rd_en, cfg->rd_noallocate, cfg->flags,
+			fb_cache_flag, fb_cache_type);
 	psde->pipe_hw->ops.setup_sys_cache(psde->pipe_hw, cfg);
 }