From 8ae09fac0077648a6e10863de21b4e96b0f6e80a Mon Sep 17 00:00:00 2001
From: Maxime Ripard <maxime@cerno.tech>
Date: Thu, 3 Sep 2020 10:01:03 +0200
Subject: drm/vc4: crtc: Clear the PixelValve FIFO during configuration
Git-commit: 9e30cfd0764e1018897b8f4830d1cffd59a3fe40
Patch-mainline: v5.10-rc1
References: jsc#SLE-15318
Even though it's not really clear why we need to flush the PV FIFO during
the configuration even though we started by flushing it, experience shows
that without it we get a stale pixel stuck in the FIFO between the HVS and
the PV.
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Tested-by: Chanwoo Choi <cw00.choi@samsung.com>
Tested-by: Hoegeun Kwon <hoegeun.kwon@samsung.com>
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Link: https://patchwork.freedesktop.org/patch/msgid/ccd6269ba37b2f849ba6e62471c99bd93a4548a0.1599120059.git-series.maxime@cerno.tech
Signed-off-by: Patrik Jakobsson <pjakobsson@suse.de>
---
drivers/gpu/drm/vc4/vc4_crtc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/vc4/vc4_crtc.c b/drivers/gpu/drm/vc4/vc4_crtc.c
index 73d918706f7e..00b2c2b011d1 100644
--- a/drivers/gpu/drm/vc4/vc4_crtc.c
+++ b/drivers/gpu/drm/vc4/vc4_crtc.c
@@ -358,7 +358,7 @@ static void vc4_crtc_config_pv(struct drm_crtc *crtc)
if (is_dsi)
CRTC_WRITE(PV_HACT_ACT, mode->hdisplay * pixel_rep);
- CRTC_WRITE(PV_CONTROL,
+ CRTC_WRITE(PV_CONTROL, PV_CONTROL_FIFO_CLR |
vc4_crtc_get_fifo_full_level_bits(vc4_crtc, format) |
VC4_SET_FIELD(format, PV_CONTROL_FORMAT) |
VC4_SET_FIELD(pixel_rep - 1, PV_CONTROL_PIXEL_REP) |
--
2.29.2