[PATCH 5.19 627/717] drm/amd/display: polling vid stream status in hpo dp blank

Greg Kroah-Hartman
2022-10-22T08:43:12Z

From: Wenjing Liu <wenjing.liu@amd.com>

[ Upstream commit e32df0c7ecead95d70ca89f39b1b2b02a59ff691 ]

[why]
vid stream control is double bufferred, if we don't wait for video
stream enable set to 0, we may get temporary image corruption
showing on the stream when setting PIXEL_TO_SYMBOL_FIFO_ENABLE to 0.

Reviewed-by: Ariel Bernstein <Eric.Bernstein@amd.com>
Acked-by: Jasdeep Dhillon <jdhillon@amd.com>
Signed-off-by: Wenjing Liu <wenjing.liu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
.../drm/amd/display/dc/dcn31/dcn31_hpo_dp_stream_encoder.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hpo_dp_stream_encoder.c b/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hpo_dp_stream_encoder.c
index 23621ff08c90..52fb2bf3d578 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hpo_dp_stream_encoder.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn31/dcn31_hpo_dp_stream_encoder.c
@@ -150,9 +150,9 @@ static void dcn31_hpo_dp_stream_enc_dp_blank(
* 10us*5000=50ms. This covers 41.7ms of minimum 24 Hz mode +
* a little more because we may not trust delay accuracy.
*/
- //REG_WAIT(DP_SYM32_ENC_VID_STREAM_CONTROL,
- // VID_STREAM_STATUS, 0,
- // 10, 5000);
+ REG_WAIT(DP_SYM32_ENC_VID_STREAM_CONTROL,
+ VID_STREAM_STATUS, 0,
+ 10, 5000);

/* Disable SDP tranmission */
REG_UPDATE(DP_SYM32_ENC_SDP_CONTROL,
--
2.35.1