drm/msm/dpu: don't use unsupported blend stages

The dpu_crtc_atomic_check() compares blending stage with DPU_STAGE_MAX
(maximum amount of blending stages supported by the driver), however we
should compare it against .max_mixer_blendstages, the maximum blend
stage supported by the mixer.

Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
Tested-by: Abhinav Kumar <quic_abhinavk@quicinc.com> # sc7280
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Patchwork: https://patchwork.freedesktop.org/patch/527338/
Link: https://lore.kernel.org/r/20230316161653.4106395-16-dmitry.baryshkov@linaro.org
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>

diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
index 351b00c..94e8bda 100644 (file)
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
@@ -1154,6 +1154,7 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
                                                                          crtc);
        struct dpu_crtc *dpu_crtc = to_dpu_crtc(crtc);
        struct dpu_crtc_state *cstate = to_dpu_crtc_state(crtc_state);
+       struct dpu_kms *dpu_kms = _dpu_crtc_get_kms(crtc);
 
        const struct drm_plane_state *pstate;
        struct drm_plane *plane;
@@ -1189,7 +1190,7 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
        drm_atomic_crtc_state_for_each_plane_state(plane, pstate, crtc_state) {
                struct dpu_plane_state *dpu_pstate = to_dpu_plane_state(pstate);
                struct drm_rect dst, clip = crtc_rect;
-               int z_pos;
+               int stage;
 
                if (IS_ERR_OR_NULL(pstate)) {
                        rc = PTR_ERR(pstate);
@@ -1214,17 +1215,16 @@ static int dpu_crtc_atomic_check(struct drm_crtc *crtc,
                        return -E2BIG;
                }
 
-               z_pos = pstate->normalized_zpos;
-
-               /* verify z_pos setting before using it */
-               if (z_pos >= DPU_STAGE_MAX - DPU_STAGE_0) {
+               /* verify stage setting before using it */
+               stage = DPU_STAGE_0 + pstate->normalized_zpos;
+               if (stage >= dpu_kms->catalog->caps->max_mixer_blendstages) {
                        DPU_ERROR("> %d plane stages assigned\n",
-                                       DPU_STAGE_MAX - DPU_STAGE_0);
+                                 dpu_kms->catalog->caps->max_mixer_blendstages - DPU_STAGE_0);
                        return -EINVAL;
                }
 
-               to_dpu_plane_state(pstate)->stage = z_pos + DPU_STAGE_0;
-               DRM_DEBUG_ATOMIC("%s: zpos %d\n", dpu_crtc->name, z_pos);
+               to_dpu_plane_state(pstate)->stage = stage;
+               DRM_DEBUG_ATOMIC("%s: stage %d\n", dpu_crtc->name, stage);
 
        }