[PATCH v10 10/12] drm/msm/dpu: support SSPP assignment for quad-pipe case

Jun Nie jun.nie at linaro.org
Mon May 26 09:28:28 UTC 2025


Currently, SSPPs are assigned to a maximum of two pipes. However,
quad-pipe usage scenarios require four pipes and involve configuring
two stages. In quad-pipe case, the first two pipes share a set of
mixer configurations and enable multi-rect mode when certain
conditions are met. The same applies to the subsequent two pipes.

Assign SSPPs to the pipes in each stage using a unified method and
to loop the stages accordingly.

Signed-off-by: Jun Nie <jun.nie at linaro.org>
---
 drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c  |  11 +++
 drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h  |   2 +
 drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c | 126 ++++++++++++++++++------------
 3 files changed, 88 insertions(+), 51 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
index 85f585206218f4578e18b00452762dbada060e9c..47ab43dfec76acc058fb275d1928603e8e8e7fc6 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
@@ -1562,6 +1562,17 @@ int dpu_crtc_vblank(struct drm_crtc *crtc, bool en)
 	return 0;
 }
 
+/**
+ * dpu_crtc_get_num_lm - Get mixer number in this CRTC pipeline
+ * @state: Pointer to drm crtc state object
+ */
+unsigned int dpu_crtc_get_num_lm(const struct drm_crtc_state *state)
+{
+	struct dpu_crtc_state *cstate = to_dpu_crtc_state(state);
+
+	return cstate->num_mixers;
+}
+
 #ifdef CONFIG_DEBUG_FS
 static int _dpu_debugfs_status_show(struct seq_file *s, void *data)
 {
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h
index 94392b9b924546f96e738ae20920cf9afd568e6b..6eaba5696e8e6bd1246a9895c4c8714ca6589b10 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.h
@@ -267,4 +267,6 @@ static inline enum dpu_crtc_client_type dpu_crtc_get_client_type(
 
 void dpu_crtc_frame_event_cb(struct drm_crtc *crtc, u32 event);
 
+unsigned int dpu_crtc_get_num_lm(const struct drm_crtc_state *state);
+
 #endif /* _DPU_CRTC_H_ */
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
index 0bb153a71353ca9eaca138ebbee4cd699414771d..f721dc504bbbe3a49986239adee113bfb6790f70 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
@@ -961,6 +961,33 @@ static int dpu_plane_is_multirect_parallel_capable(struct dpu_hw_sspp *sspp,
 		dpu_plane_is_parallel_capable(pipe_cfg, fmt, max_linewidth);
 }
 
+static bool dpu_plane_check_single_pipe(struct dpu_plane_state *pstate,
+					struct dpu_sw_pipe **single_pipe,
+					struct dpu_sw_pipe_cfg **single_pipe_cfg,
+					bool config_pipe)
+{
+	int i, valid_pipe = 0;
+	struct dpu_sw_pipe *pipe;
+
+	for (i = 0; i < PIPES_PER_PLANE; i++) {
+		if (drm_rect_width(&pstate->pipe_cfg[i].src_rect) != 0) {
+			valid_pipe++;
+			if (valid_pipe > 1)
+				return false;
+			*single_pipe = &pstate->pipe[i];
+			*single_pipe_cfg = &pstate->pipe_cfg[i];
+		} else {
+			if (!config_pipe)
+				continue;
+			pipe = &pstate->pipe[i];
+			pipe->multirect_index = DPU_SSPP_RECT_SOLO;
+			pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
+			pipe->sspp = NULL;
+		}
+	}
+
+	return true;
+}
 
 static int dpu_plane_atomic_check_sspp(struct drm_plane *plane,
 				       struct drm_atomic_state *state,
@@ -1028,15 +1055,15 @@ static int dpu_plane_try_multirect_shared(struct dpu_plane_state *pstate,
 					  const struct msm_format *fmt,
 					  uint32_t max_linewidth)
 {
-	struct dpu_sw_pipe *pipe = &pstate->pipe[0];
-	struct dpu_sw_pipe *r_pipe = &pstate->pipe[1];
-	struct dpu_sw_pipe_cfg *pipe_cfg = &pstate->pipe_cfg[0];
-	struct dpu_sw_pipe *prev_pipe = &prev_adjacent_pstate->pipe[0];
-	struct dpu_sw_pipe_cfg *prev_pipe_cfg = &prev_adjacent_pstate->pipe_cfg[0];
+	struct dpu_sw_pipe *pipe, *prev_pipe;
+	struct dpu_sw_pipe_cfg *pipe_cfg, *prev_pipe_cfg;
 	const struct msm_format *prev_fmt = msm_framebuffer_format(prev_adjacent_pstate->base.fb);
 	u16 max_tile_height = 1;
 
-	if (prev_adjacent_pstate->pipe[1].sspp != NULL ||
+	if (!dpu_plane_check_single_pipe(pstate, &pipe, &pipe_cfg, true))
+		return false;
+
+	if (!dpu_plane_check_single_pipe(prev_adjacent_pstate, &prev_pipe, &prev_pipe_cfg, false) ||
 	    prev_pipe->multirect_mode != DPU_SSPP_MULTIRECT_NONE)
 		return false;
 
@@ -1050,11 +1077,6 @@ static int dpu_plane_try_multirect_shared(struct dpu_plane_state *pstate,
 	if (MSM_FORMAT_IS_UBWC(prev_fmt))
 		max_tile_height = max(max_tile_height, prev_fmt->tile_height);
 
-	r_pipe->multirect_index = DPU_SSPP_RECT_SOLO;
-	r_pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
-
-	r_pipe->sspp = NULL;
-
 	if (dpu_plane_is_parallel_capable(pipe_cfg, fmt, max_linewidth) &&
 	    dpu_plane_is_parallel_capable(prev_pipe_cfg, prev_fmt, max_linewidth) &&
 	    (pipe_cfg->dst_rect.x1 >= prev_pipe_cfg->dst_rect.x2 ||
@@ -1194,12 +1216,11 @@ static int dpu_plane_virtual_assign_resources(struct drm_crtc *crtc,
 	struct dpu_kms *dpu_kms = _dpu_plane_get_kms(plane);
 	struct dpu_rm_sspp_requirements reqs;
 	struct dpu_plane_state *pstate, *prev_adjacent_pstate;
-	struct dpu_sw_pipe *pipe;
-	struct dpu_sw_pipe *r_pipe;
-	struct dpu_sw_pipe_cfg *pipe_cfg;
-	struct dpu_sw_pipe_cfg *r_pipe_cfg;
+	struct dpu_sw_pipe *pipe, *r_pipe;
+	struct dpu_sw_pipe_cfg *pipe_cfg, *r_pipe_cfg;
+	struct dpu_plane *pdpu = to_dpu_plane(plane);
 	const struct msm_format *fmt;
-	int i;
+	int i, num_lm, stage_id, num_stages;
 
 	if (plane_state->crtc)
 		crtc_state = drm_atomic_get_new_crtc_state(state,
@@ -1209,11 +1230,6 @@ static int dpu_plane_virtual_assign_resources(struct drm_crtc *crtc,
 	prev_adjacent_pstate = prev_adjacent_plane_state ?
 		to_dpu_plane_state(prev_adjacent_plane_state) : NULL;
 
-	pipe = &pstate->pipe[0];
-	r_pipe = &pstate->pipe[1];
-	pipe_cfg = &pstate->pipe_cfg[0];
-	r_pipe_cfg = &pstate->pipe_cfg[1];
-
 	for (i = 0; i < PIPES_PER_PLANE; i++)
 		pstate->pipe[i].sspp = NULL;
 
@@ -1227,44 +1243,52 @@ static int dpu_plane_virtual_assign_resources(struct drm_crtc *crtc,
 
 	reqs.rot90 = drm_rotation_90_or_270(plane_state->rotation);
 
-	if (drm_rect_width(&r_pipe_cfg->src_rect) == 0) {
-		if (!prev_adjacent_pstate ||
-		    !dpu_plane_try_multirect_shared(pstate, prev_adjacent_pstate, fmt,
-						    dpu_kms->catalog->caps->max_linewidth)) {
-			pipe->sspp = dpu_rm_reserve_sspp(&dpu_kms->rm, global_state, crtc, &reqs);
-			if (!pipe->sspp)
-				return -ENODEV;
+	if (prev_adjacent_pstate &&
+	    dpu_plane_try_multirect_shared(pstate, prev_adjacent_pstate, fmt,
+					    dpu_kms->catalog->caps->max_linewidth)) {
+		goto assigned;
+	}
 
-			r_pipe->sspp = NULL;
+	num_lm = dpu_crtc_get_num_lm(crtc_state);
+	num_stages = (num_lm + 1) / 2;
+	for (stage_id = 0; stage_id < num_stages; stage_id++) {
+		for (i = stage_id * PIPES_PER_STAGE; i < (stage_id + 1) * PIPES_PER_STAGE; i++) {
+			pipe = &pstate->pipe[i];
+			pipe_cfg = &pstate->pipe_cfg[i];
 
-			pipe->multirect_index = DPU_SSPP_RECT_SOLO;
-			pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
+			if (drm_rect_width(&pipe_cfg->src_rect) == 0)
+				break;
 
-			r_pipe->multirect_index = DPU_SSPP_RECT_SOLO;
-			r_pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
-		}
-	} else {
-		pipe->sspp = dpu_rm_reserve_sspp(&dpu_kms->rm, global_state, crtc, &reqs);
-		if (!pipe->sspp)
-			return -ENODEV;
-
-		if (!dpu_plane_try_multirect_parallel(pipe, pipe_cfg, r_pipe, r_pipe_cfg,
-						      pipe->sspp,
-						      msm_framebuffer_format(plane_state->fb),
-						      dpu_kms->catalog->caps->max_linewidth)) {
-			/* multirect is not possible, use two SSPP blocks */
-			r_pipe->sspp = dpu_rm_reserve_sspp(&dpu_kms->rm, global_state, crtc, &reqs);
-			if (!r_pipe->sspp)
+			pipe->sspp = dpu_rm_reserve_sspp(&dpu_kms->rm, global_state, crtc, &reqs);
+			if (!pipe->sspp)
 				return -ENODEV;
 
-			pipe->multirect_index = DPU_SSPP_RECT_SOLO;
-			pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
-
-			r_pipe->multirect_index = DPU_SSPP_RECT_SOLO;
-			r_pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
+			r_pipe = &pstate->pipe[i + 1];
+			r_pipe_cfg = &pstate->pipe_cfg[i + 1];
+
+			/*
+			 * If current pipe is the first pipe in pipe pair, check
+			 * multi-rect opportunity for the 2nd pipe in the pair.
+			 * SSPP multi-rect mode cross mixer pairs is not supported.
+			 */
+			if ((i % PIPES_PER_STAGE == 0) &&
+			    drm_rect_width(&r_pipe_cfg->src_rect) != 0 &&
+			    dpu_plane_try_multirect_parallel(pipe, pipe_cfg, r_pipe, r_pipe_cfg,
+							      pipe->sspp,
+							      msm_framebuffer_format(plane_state->fb),
+							      dpu_kms->catalog->caps->max_linewidth)) {
+				i++;
+			} else {
+				/* multirect is not possible, use two SSPP blocks */
+				pipe->multirect_index = DPU_SSPP_RECT_SOLO;
+				pipe->multirect_mode = DPU_SSPP_MULTIRECT_NONE;
+				DPU_DEBUG_PLANE(pdpu, "allocating sspp_%d for pipe %d.\n",
+						pipe->sspp->idx - SSPP_NONE, i);
+			}
 		}
 	}
 
+assigned:
 	return dpu_plane_atomic_check_sspp(plane, state, crtc_state);
 }
 

-- 
2.34.1



More information about the dri-devel mailing list