On 03/04/2023 19:11, Dmitry Baryshkov wrote:
On Mon, 3 Apr 2023 at 15:01, Vinod Polimera <vpolimer@xxxxxxxxxxxxxxxx> wrote:
On Fri, 31 Mar 2023 at 16:59, Vinod Polimera <quic_vpolimer@xxxxxxxxxxx>
wrote:
In certain CPU stress conditions, there can be a delay in scheduling commit
work and it was observed that PSR commit from a different work queue
was
scheduled. Avoid these commits as display is already in PSR mode.
Signed-off-by: Vinod Polimera <quic_vpolimer@xxxxxxxxxxx>
---
drivers/gpu/drm/msm/msm_atomic.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/gpu/drm/msm/msm_atomic.c
b/drivers/gpu/drm/msm/msm_atomic.c
index 645fe53..f8141bb 100644
--- a/drivers/gpu/drm/msm/msm_atomic.c
+++ b/drivers/gpu/drm/msm/msm_atomic.c
@@ -192,6 +192,9 @@ int msm_atomic_check(struct drm_device *dev,
struct drm_atomic_state *state)
new_crtc_state->mode_changed = true;
state->allow_modeset = true;
}
+
+ if (old_crtc_state->self_refresh_active && new_crtc_state-
self_refresh_active)
+ return -EINVAL;
EINVAL here means that atomic_check will fail if both old and new
states are in SR mode. For example, there might be a mode set for
another CRTC (while keeping this one in SR mode). I don't think this
is correct. We should skip/shortcut the commit, that's true. But I
doubt that returning an error here is a proper way to do this. Please
correct me if I'm wrong.
If there is a modeset on same crtc with a different connector. The new_crtc_state will not have self_refresh_active set.
Self_refresh_active is set from the helper library, which will duplicate the old_state and just adds self_refresh_active to true and active to false.
so we can be confident that if we are checking for self_refresh_active status then it should be coming from the library call.
Also the EINVAL is returned to the self_refresh library API and the function will be retired.
Maybe I misunderstand you here. However, in this way EINVAL is
returned to drm_atomic_check_only() and not to the SR code.
Unless anybody objects, I'm going to drop this patch now. The issue
should be solved in the framework itself.
And self_refresh_active is cleared on every commit : https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/tree/drivers/gpu/drm/drm_atomic_state_helper.c#n158
And this means that this check will not trigger at all, if I'm not
mistaken. You've added code to msm_atomic_check(), so
drm_self_refresh_helper_alter_state() was not called (yet) and thus
new_crtc_state->self_refresh_active is set to false, fresh after
crtc's duplicate_state.
--
With best wishes
Dmitry
--
With best wishes
Dmitry
