Re: [PATCH v8 12/15] drm/msm/dpu: blend pipes per mixer pairs config

[Jessica Zhang]

On 3/3/2025 7:14 AM, Jun Nie wrote:

Currently, only 2 pipes are used at most for a plane. A stage structure
describes the configuration for a mixer pair. So only one stage is needed
for current usage cases. The quad-pipe case will be added in future and 2
stages are used in the case. So extend the stage to an array with array
size STAGES_PER_PLANE and blend pipes per mixer pair with configuration
in the stage structure.

Signed-off-by: Jun Nie <jun....@linaro.org>
Reviewed-by: Dmitry Baryshkov <dmitry.barysh...@linaro.org>

Reviewed-by: Jessica Zhang <quic_jessz...@quicinc.com>

---
  drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 46 +++++++++++++++++++++-----------
  1 file changed, 30 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c 
b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
index 
81474823e6799132db71c9712046d359e3535d90..6fbe42e8988edac7e7917ae8de180aefdaf443e9
 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
@@ -392,7 +392,7 @@ static void _dpu_crtc_program_lm_output_roi(struct drm_crtc 
*crtc)
  static void _dpu_crtc_blend_setup_pipe(struct drm_crtc *crtc,
                                       struct drm_plane *plane,
                                       struct dpu_crtc_mixer *mixer,
-                                      u32 num_mixers,
+                                      u32 lms_in_stage,
                                       enum dpu_stage stage,
                                       const struct msm_format *format,
                                       uint64_t modifier,
@@ -426,7 +426,7 @@ static void _dpu_crtc_blend_setup_pipe(struct drm_crtc 
*crtc,
        stage_cfg->multirect_index[stage][stage_idx] = pipe->multirect_index;

/* blend config update */

-       for (lm_idx = 0; lm_idx < num_mixers; lm_idx++)
+       for (lm_idx = 0; lm_idx < lms_in_stage; lm_idx++)
                
mixer[lm_idx].lm_ctl->ops.update_pending_flush_sspp(mixer[lm_idx].lm_ctl, 
sspp_idx);
  }

@@ -442,7 +442,7 @@ static void _dpu_crtc_blend_setup_mixer(struct drm_crtc *crtc,

        const struct msm_format *format;
        struct dpu_hw_ctl *ctl = mixer->lm_ctl;

- uint32_t lm_idx, i;

+       uint32_t lm_idx, stage, i, pipe_idx, head_pipe_in_stage, lms_in_stage;
        bool bg_alpha_enable = false;
        DECLARE_BITMAP(fetch_active, SSPP_MAX);

@@ -463,15 +463,25 @@ static void _dpu_crtc_blend_setup_mixer(struct drm_crtc *crtc,

                if (pstate->stage == DPU_STAGE_BASE && format->alpha_enable)
                        bg_alpha_enable = true;

- for (i = 0; i < PIPES_PER_PLANE; i++) {

-                       if (!pstate->pipe[i].sspp)
-                               continue;
-                       set_bit(pstate->pipe[i].sspp->idx, fetch_active);
-                       _dpu_crtc_blend_setup_pipe(crtc, plane,
-                                                  mixer, cstate->num_mixers,
-                                                  pstate->stage,
-                                                  format, fb ? fb->modifier : 
0,
-                                                  &pstate->pipe[i], i, 
stage_cfg);
+               /* loop pipe per mixer pair with config in stage structure */
+               for (stage = 0; stage < STAGES_PER_PLANE; stage++) {
+                       head_pipe_in_stage = stage * PIPES_PER_STAGE;
+                       for (i = 0; i < PIPES_PER_STAGE; i++) {
+                               pipe_idx = i + head_pipe_in_stage;
+                               if (!pstate->pipe[pipe_idx].sspp)
+                                       continue;
+
+                               lms_in_stage = min(cstate->num_mixers - (stage 
* PIPES_PER_STAGE),
+                                                 PIPES_PER_STAGE);
+                               set_bit(pstate->pipe[pipe_idx].sspp->idx, 
fetch_active);
+                               _dpu_crtc_blend_setup_pipe(crtc, plane,
+                                                          
&mixer[head_pipe_in_stage],
+                                                          lms_in_stage,
+                                                          pstate->stage,
+                                                          format, fb ? 
fb->modifier : 0,
+                                                          
&pstate->pipe[pipe_idx], i,
+                                                          &stage_cfg[stage]);
+                       }
                }

/* blend config update */

@@ -503,7 +513,7 @@ static void _dpu_crtc_blend_setup(struct drm_crtc *crtc)
        struct dpu_crtc_mixer *mixer = cstate->mixers;
        struct dpu_hw_ctl *ctl;
        struct dpu_hw_mixer *lm;
-       struct dpu_hw_stage_cfg stage_cfg;
+       struct dpu_hw_stage_cfg stage_cfg[STAGES_PER_PLANE];
        int i;

DRM_DEBUG_ATOMIC("%s\n", dpu_crtc->name);

@@ -516,9 +526,9 @@ static void _dpu_crtc_blend_setup(struct drm_crtc *crtc)
        }

/* initialize stage cfg */

-       memset(&stage_cfg, 0, sizeof(struct dpu_hw_stage_cfg));
+       memset(&stage_cfg, 0, sizeof(stage_cfg));

- _dpu_crtc_blend_setup_mixer(crtc, dpu_crtc, mixer, &stage_cfg);

+       _dpu_crtc_blend_setup_mixer(crtc, dpu_crtc, mixer, stage_cfg);

for (i = 0; i < cstate->num_mixers; i++) {

                ctl = mixer[i].lm_ctl;
@@ -535,8 +545,12 @@ static void _dpu_crtc_blend_setup(struct drm_crtc *crtc)
                        mixer[i].mixer_op_mode,
                        ctl->idx - CTL_0);

+ /*

+                * call dpu_hw_ctl_setup_blendstage() to blend layers per stage 
cfg.
+                * stage data is shared between PIPES_PER_STAGE pipes.
+                */
                ctl->ops.setup_blendstage(ctl, mixer[i].hw_lm->idx,
-                       &stage_cfg);
+                       &stage_cfg[i / PIPES_PER_STAGE]);
        }
  }

--
2.34.1