2023-08-04 20:13:00

by Hamza Mahfooz

[permalink] [raw]
Subject: [PATCH v2] drm/amd/display: ensure async flips are only accepted for fast updates

We should be checking to see if async flips are supported in
amdgpu_dm_atomic_check() (i.e. not dm_crtc_helper_atomic_check()). Also,
async flipping isn't supported if a plane's framebuffer changes memory
domains during an atomic commit. So, move the check from
dm_crtc_helper_atomic_check() to amdgpu_dm_atomic_check() and check if
the memory domain has changed in amdgpu_dm_atomic_check().

Cc: [email protected]
Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2733
Fixes: 3f86b60691e6 ("drm/amd/display: only accept async flips for fast updates")
Signed-off-by: Hamza Mahfooz <[email protected]>
---
v2: link issue and revert back to the old way of setting update_type.
---
.../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 24 ++++++++++++++++---
.../amd/display/amdgpu_dm/amdgpu_dm_crtc.c | 12 ----------
2 files changed, 21 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 32fb551862b0..1d3afab5bc85 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -8086,10 +8086,12 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
* fast updates.
*/
if (crtc->state->async_flip &&
- acrtc_state->update_type != UPDATE_TYPE_FAST)
+ (acrtc_state->update_type != UPDATE_TYPE_FAST ||
+ get_mem_type(old_plane_state->fb) != get_mem_type(fb)))
drm_warn_once(state->dev,
"[PLANE:%d:%s] async flip with non-fast update\n",
plane->base.id, plane->name);
+
bundle->flip_addrs[planes_count].flip_immediate =
crtc->state->async_flip &&
acrtc_state->update_type == UPDATE_TYPE_FAST &&
@@ -10050,6 +10052,11 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,

/* Remove exiting planes if they are modified */
for_each_oldnew_plane_in_state_reverse(state, plane, old_plane_state, new_plane_state, i) {
+ if (old_plane_state->fb && new_plane_state->fb &&
+ get_mem_type(old_plane_state->fb) !=
+ get_mem_type(new_plane_state->fb))
+ lock_and_validation_needed = true;
+
ret = dm_update_plane_state(dc, state, plane,
old_plane_state,
new_plane_state,
@@ -10297,9 +10304,20 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
struct dm_crtc_state *dm_new_crtc_state =
to_dm_crtc_state(new_crtc_state);

+ /*
+ * Only allow async flips for fast updates that don't change
+ * the FB pitch, the DCC state, rotation, etc.
+ */
+ if (new_crtc_state->async_flip && lock_and_validation_needed) {
+ drm_dbg_atomic(crtc->dev,
+ "[CRTC:%d:%s] async flips are only supported for fast updates\n",
+ crtc->base.id, crtc->name);
+ ret = -EINVAL;
+ goto fail;
+ }
+
dm_new_crtc_state->update_type = lock_and_validation_needed ?
- UPDATE_TYPE_FULL :
- UPDATE_TYPE_FAST;
+ UPDATE_TYPE_FULL : UPDATE_TYPE_FAST;
}

/* Must be success */
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
index 30d4c6fd95f5..440fc0869a34 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
@@ -398,18 +398,6 @@ static int dm_crtc_helper_atomic_check(struct drm_crtc *crtc,
return -EINVAL;
}

- /*
- * Only allow async flips for fast updates that don't change the FB
- * pitch, the DCC state, rotation, etc.
- */
- if (crtc_state->async_flip &&
- dm_crtc_state->update_type != UPDATE_TYPE_FAST) {
- drm_dbg_atomic(crtc->dev,
- "[CRTC:%d:%s] async flips are only supported for fast updates\n",
- crtc->base.id, crtc->name);
- return -EINVAL;
- }
-
/* In some use cases, like reset, no stream is attached */
if (!dm_crtc_state->stream)
return 0;
--
2.41.0



2023-08-04 20:30:58

by Harry Wentland

[permalink] [raw]
Subject: Re: [PATCH v2] drm/amd/display: ensure async flips are only accepted for fast updates



On 2023-08-04 14:20, Hamza Mahfooz wrote:
> We should be checking to see if async flips are supported in
> amdgpu_dm_atomic_check() (i.e. not dm_crtc_helper_atomic_check()). Also,
> async flipping isn't supported if a plane's framebuffer changes memory
> domains during an atomic commit. So, move the check from
> dm_crtc_helper_atomic_check() to amdgpu_dm_atomic_check() and check if
> the memory domain has changed in amdgpu_dm_atomic_check().
>
> Cc: [email protected]
> Link: https://gitlab.freedesktop.org/drm/amd/-/issues/2733
> Fixes: 3f86b60691e6 ("drm/amd/display: only accept async flips for fast updates")
> Signed-off-by: Hamza Mahfooz <[email protected]>

Reviewed-by: Harry Wentland <[email protected]>

Harry

> ---
> v2: link issue and revert back to the old way of setting update_type.
> ---
> .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 24 ++++++++++++++++---
> .../amd/display/amdgpu_dm/amdgpu_dm_crtc.c | 12 ----------
> 2 files changed, 21 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> index 32fb551862b0..1d3afab5bc85 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
> @@ -8086,10 +8086,12 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_state *state,
> * fast updates.
> */
> if (crtc->state->async_flip &&
> - acrtc_state->update_type != UPDATE_TYPE_FAST)
> + (acrtc_state->update_type != UPDATE_TYPE_FAST ||
> + get_mem_type(old_plane_state->fb) != get_mem_type(fb)))
> drm_warn_once(state->dev,
> "[PLANE:%d:%s] async flip with non-fast update\n",
> plane->base.id, plane->name);
> +
> bundle->flip_addrs[planes_count].flip_immediate =
> crtc->state->async_flip &&
> acrtc_state->update_type == UPDATE_TYPE_FAST &&
> @@ -10050,6 +10052,11 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
>
> /* Remove exiting planes if they are modified */
> for_each_oldnew_plane_in_state_reverse(state, plane, old_plane_state, new_plane_state, i) {
> + if (old_plane_state->fb && new_plane_state->fb &&
> + get_mem_type(old_plane_state->fb) !=
> + get_mem_type(new_plane_state->fb))
> + lock_and_validation_needed = true;
> +
> ret = dm_update_plane_state(dc, state, plane,
> old_plane_state,
> new_plane_state,
> @@ -10297,9 +10304,20 @@ static int amdgpu_dm_atomic_check(struct drm_device *dev,
> struct dm_crtc_state *dm_new_crtc_state =
> to_dm_crtc_state(new_crtc_state);
>
> + /*
> + * Only allow async flips for fast updates that don't change
> + * the FB pitch, the DCC state, rotation, etc.
> + */
> + if (new_crtc_state->async_flip && lock_and_validation_needed) {
> + drm_dbg_atomic(crtc->dev,
> + "[CRTC:%d:%s] async flips are only supported for fast updates\n",
> + crtc->base.id, crtc->name);
> + ret = -EINVAL;
> + goto fail;
> + }
> +
> dm_new_crtc_state->update_type = lock_and_validation_needed ?
> - UPDATE_TYPE_FULL :
> - UPDATE_TYPE_FAST;
> + UPDATE_TYPE_FULL : UPDATE_TYPE_FAST;
> }
>
> /* Must be success */
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
> index 30d4c6fd95f5..440fc0869a34 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c
> @@ -398,18 +398,6 @@ static int dm_crtc_helper_atomic_check(struct drm_crtc *crtc,
> return -EINVAL;
> }
>
> - /*
> - * Only allow async flips for fast updates that don't change the FB
> - * pitch, the DCC state, rotation, etc.
> - */
> - if (crtc_state->async_flip &&
> - dm_crtc_state->update_type != UPDATE_TYPE_FAST) {
> - drm_dbg_atomic(crtc->dev,
> - "[CRTC:%d:%s] async flips are only supported for fast updates\n",
> - crtc->base.id, crtc->name);
> - return -EINVAL;
> - }
> -
> /* In some use cases, like reset, no stream is attached */
> if (!dm_crtc_state->stream)
> return 0;