On 2021-07-04 18:21, 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).
Userspace assigning several planes to a single zpos was intended to
identify
cases where src split can be used. Downstream does not use normalized
zpos,
hence it did not come across as a bug but mostly as a way to identify
when
usermode needs src split to be enabled based on the composition
strategy.
We can talk about that more in the rest of the patches of this series.
For this one, I only have a couple of questions:
1) Across different vendors, some have gone with limiting the zpos and
some have gone with
the max, so is there an issue with sticking with the max_blend_stages
limit?
2) If there is no hard reason to make this change, I think its better to
keep it the way it is.
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
---
drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c | 11 +----------
1 file changed, 1 insertion(+), 10 deletions(-)
diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
index 8ed7b8f0db69..3850f2714bf3 100644
--- a/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
+++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c
@@ -44,7 +44,6 @@
#define DPU_NAME_SIZE 12
#define DPU_PLANE_COLOR_FILL_FLAG BIT(31)
-#define DPU_ZPOS_MAX 255
/* multirect rect index */
enum {
@@ -1374,7 +1373,6 @@ 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;
@@ -1412,14 +1410,7 @@ 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, 255);
if (ret)
DPU_ERROR("failed to install zpos property, rc = %d\n", ret);