SUNLIGHT: drm/amd/display: Clean up stale page flip state on timeout

Description:
 - When a page flip times out waiting for hw_done or flip_done completion,
   the event and pflip_status are left in a stale state. This causes
   WARN_ON triggers in prepare_flip_isr on subsequent commits because the
   hardware never signaled completion of the previous flip.

   Add cleanup logic to manually send the vblank event, release the vblank
   reference, and reset pflip_status to AMDGPU_FLIP_NONE when a timeout
   occurs. This prevents state corruption and eliminates spurious warnings
   on future commits.

Change-Id: I2c59946fadf179f071f999291b4cc30225fcb9a6
Signed-off-by: Ionut Nechita <[email protected]>

Author: ionutnechita

drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c

@@ -10685,10 +10685,29 @@ static int do_aquire_global_lock(struct drm_device *dev,
 			ret = wait_for_completion_interruptible_timeout(
 					&commit->flip_done, 10*HZ);
 
-		if (ret == 0)
+		if (ret == 0) {
+			struct amdgpu_crtc *acrtc = to_amdgpu_crtc(crtc);
+			unsigned long flags;
+
 			drm_err(dev, "[CRTC:%d:%s] hw_done or flip_done timed out\n",
 				  crtc->base.id, crtc->name);
 
+			/*
+			 * Clean up stale event and pflip_status to prevent
+			 * WARN_ON in prepare_flip_isr on subsequent commits.
+			 * If the flip timed out, the hardware did not signal
+			 * completion, so we need to manually clean up the state.
+			 */
+			spin_lock_irqsave(&dev->event_lock, flags);
+			if (acrtc->event) {
+				drm_crtc_send_vblank_event(crtc, acrtc->event);
+				acrtc->event = NULL;
+				drm_crtc_vblank_put(crtc);
+			}
+			acrtc->pflip_status = AMDGPU_FLIP_NONE;
+			spin_unlock_irqrestore(&dev->event_lock, flags);
+		}
+
 		drm_crtc_commit_put(commit);
 	}