drm: rcar-du: Setup planes before enabling CRTC to avoid flicker

Commit 52055bafa1ff ("drm: rcar-du: Move plane commit code from CRTC
start to CRTC resume") changed the order of the plane commit and CRTC
enable operations to accommodate the runtime PM requirements. However,
this introduced corruption in the first displayed frame, as the CRTC is
now enabled without any plane configured. On Gen2 hardware the first
frame will be black and likely unnoticed, but on Gen3 hardware we end up
starting the display before the VSP compositor, which is more
noticeable.

To fix this, revert the order of the commit operations back, and handle
runtime PM requirements in the CRTC .atomic_begin() and .atomic_enable()
helper operation handlers.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@ideasonboard.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.h b/drivers/gpu/drm/rcar-du/rcar_du_crtc.h
index 0b6d26ecfc38..3cc376826592 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.h
+++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.h
@@ -30,7 +30,7 @@ struct rcar_du_vsp;
  * @extclock: external pixel dot clock (optional)
  * @mmio_offset: offset of the CRTC registers in the DU MMIO block
  * @index: CRTC software and hardware index
- * @started: whether the CRTC has been started and is running
+ * @initialized: whether the CRTC has been initialized and clocks enabled
  * @event: event to post when the pending page flip completes
  * @flip_wait: wait queue used to signal page flip completion
  * @outputs: bitmask of the outputs (enum rcar_du_output) driven by this CRTC
@@ -45,7 +45,7 @@ struct rcar_du_crtc {
 	struct clk *extclock;
 	unsigned int mmio_offset;
 	unsigned int index;
-	bool started;
+	bool initialized;
 
 	struct drm_pending_vblank_event *event;
 	wait_queue_head_t flip_wait;