[PATCH v5 30/80] drm/vc4: crtc: Clear the PixelValve FIFO on disable

[Maxime Ripard]

In order to avoid a stale pixel getting stuck on mode change or a disable
/ enable cycle, we need to make sure to flush the PV FIFO on disable.

Reviewed-by: Dave Stevenson <dave.stevenson@xxxxxxxxxxxxxxx>
Tested-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
Tested-by: Hoegeun Kwon <hoegeun.kwon@xxxxxxxxxxx>
Tested-by: Stefan Wahren <stefan.wahren@xxxxxxxx>
Signed-off-by: Maxime Ripard <maxime@xxxxxxxxxx>
---
 drivers/gpu/drm/vc4/vc4_crtc.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index 4c23cf8aefb9..73d918706f7e 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -424,8 +424,7 @@ static void vc4_crtc_atomic_disable(struct drm_crtc *crtc,
 	if (vc4_encoder->post_crtc_disable)
 		vc4_encoder->post_crtc_disable(encoder);
 
-	CRTC_WRITE(PV_CONTROL, CRTC_READ(PV_CONTROL) & ~PV_CONTROL_EN);
-
+	vc4_crtc_pixelvalve_reset(crtc);
 	vc4_hvs_atomic_disable(crtc, old_state);
 
 	if (vc4_encoder->post_crtc_powerdown)
-- 
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