Re: [PATCH v3 14/27] drm/msm/dpu: don't use unsupported blend stages

[Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>]

On 2/3/2023 10:21 AM, Dmitry Baryshkov wrote:
> 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.
>
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>

Reviewed-by: Abhinav Kumar <quic_abhinavk@xxxxxxxxxxx>

> ---
>   drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 16 ++++++++--------
>   1 file changed, 8 insertions(+), 8 deletions(-)
>
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> index c1579d6f5060..b485234eefb2 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> @@ -1129,6 +1129,7 @@ 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;
> @@ -1164,7 +1165,7 @@ 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);
> @@ -1189,17 +1190,16 @@ 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);
>   
>   	}
>