drm/msm: block incoming update on pending updates
We can't have multiple updates pending on a given CRTC, and we don't
want a sync update to race w/ an async update that preceeded it. So
keep track of which CRTCs have updates in flight, and block later
updates that would conflict.
Signed-off-by: Rob Clark <robdclark@gmail.com>
diff --git a/drivers/gpu/drm/msm/msm_drv.h b/drivers/gpu/drm/msm/msm_drv.h
index 1363038..b69ef2d 100644
--- a/drivers/gpu/drm/msm/msm_drv.h
+++ b/drivers/gpu/drm/msm/msm_drv.h
@@ -96,6 +96,10 @@
/* callbacks deferred until bo is inactive: */
struct list_head fence_cbs;
+ /* crtcs pending async atomic updates: */
+ uint32_t pending_crtcs;
+ wait_queue_head_t pending_crtcs_event;
+
/* registered MMUs: */
unsigned int num_mmus;
struct msm_mmu *mmus[NUM_DOMAINS];