Re: [PATCH 02/25] drm/msm/dpu: do not limit the zpos property

[Abhinav Kumar <quic_abhinavk@quicinc.com>]

On 2/9/2022 9:24 AM, Dmitry Baryshkov wrote:
> Stop limiting zpos property values, we use normalized_zpos anyway. And
> nothing stops userspace from assigning several planes to a single zpos
> (it is a userspace bug, but the kernel is forgiving about it).
> 
> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: Abhinav Kumar <quic_abhinavk@quicinc.com>
> ---
>   drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c | 10 +---------
>   1 file changed, 1 insertion(+), 9 deletions(-)
> 
> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
> index 3fcc964dec0a..c04c3be16d85 100644
> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
> @@ -1429,7 +1429,6 @@ struct drm_plane *dpu_plane_init(struct drm_device *dev,
>   	struct dpu_plane *pdpu;
>   	struct msm_drm_private *priv = dev->dev_private;
>   	struct dpu_kms *kms = to_dpu_kms(priv->kms);
> -	int zpos_max = DPU_ZPOS_MAX;
>   	uint32_t num_formats;
>   	int ret = -EINVAL;
>   
> @@ -1467,14 +1466,7 @@ struct drm_plane *dpu_plane_init(struct drm_device *dev,
>   
>   	pdpu->catalog = kms->catalog;
>   
> -	if (kms->catalog->mixer_count &&
> -		kms->catalog->mixer[0].sblk->maxblendstages) {
> -		zpos_max = kms->catalog->mixer[0].sblk->maxblendstages - 1;
> -		if (zpos_max > DPU_STAGE_MAX - DPU_STAGE_0 - 1)
> -			zpos_max = DPU_STAGE_MAX - DPU_STAGE_0 - 1;
> -	}
> -
> -	ret = drm_plane_create_zpos_property(plane, 0, 0, zpos_max);
> +	ret = drm_plane_create_zpos_property(plane, 0, 0, DPU_ZPOS_MAX);
>   	if (ret)
>   		DPU_ERROR("failed to install zpos property, rc = %d\n", ret);
>