On 2018-10-03 13:22, Sean Paul wrote:
From: Sean Paul <seanpaul@xxxxxxxxxxxx>
Similar to the atomic helpers, we should enable vblank while we're
waiting for the commit to finish. DPU needs this, MDP5 seems to work
fine without it.
Signed-off-by: Sean Paul <seanpaul@xxxxxxxxxxxx>
---
As such I dont see any issue with this patch but I have a question
overall on chrome vblank handling.
For a video mode panel, we will keep the HW resources enabled (including
vsync related clocks) till device
is suspended.
The vblank_get and vblank_put are only controlling the
register/deregister of the vblank IRQ callback which
send the events to the userspace and anything pending on vsync
completion.
Does the chrome userspace turn ON/OFF the vblank using vblank_ctrl IOCTL
Or does it guarantee it to be?
If so, is this patch just more of a safety check to make sure that vsync
events remain ON till the frame is done?
Because HW wise it should be and this shouldnt be needed.
drivers/gpu/drm/msm/msm_atomic.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/drivers/gpu/drm/msm/msm_atomic.c
b/drivers/gpu/drm/msm/msm_atomic.c
index c1f1779c980f..2b7bb6e166d3 100644
--- a/drivers/gpu/drm/msm/msm_atomic.c
+++ b/drivers/gpu/drm/msm/msm_atomic.c
@@ -32,7 +32,12 @@ static void msm_atomic_wait_for_commit_done(struct
drm_device *dev,
if (!new_crtc_state->active)
continue;
+ if (drm_crtc_vblank_get(crtc))
+ continue;
+
kms->funcs->wait_for_crtc_commit_done(kms, crtc);
+
+ drm_crtc_vblank_put(crtc);
}
}
