[PATCH 08/15] drm/amd/display: Increase timeout for DP Disable - Linux-stable-mirror

16 Sep 2020

From: Wesley Chalmers Wesley.Chalmers@amd.com
[WHY]
When disabling DP video, the current REG_WAIT timeout
of 50ms is too low for certain cases with very high
VSYNC intervals.
[HOW]
Increase the timeout to 102ms, so that
refresh rates as low as 10Hz can be handled properly.
Signed-off-by: Wesley Chalmers Wesley.Chalmers@amd.com
Reviewed-by: Aric Cyr Aric.Cyr@amd.com
Acked-by: Qingqing Zhuo qingqing.zhuo@amd.com
Cc: stable@vger.kernel.org
---
 drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c
index 9cf139be3f40..f70fcadf1ee5 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn10/dcn10_stream_encoder.c
@@ -896,10 +896,10 @@ void enc1_stream_encoder_dp_blank(
     */
    REG_UPDATE(DP_VID_STREAM_CNTL, DP_VID_STREAM_DIS_DEFER, 2);
    /* Larger delay to wait until VBLANK - use max retry of
-	 * 10us*5000=50ms. This covers 41.7ms of minimum 24 Hz mode +
+	 * 10us*10200=102ms. This covers 100.0ms of minimum 10 Hz mode +
     * a little more because we may not trust delay accuracy.
     */
-	max_retries = DP_BLANK_MAX_RETRY * 250;
+	max_retries = DP_BLANK_MAX_RETRY * 501;
/* disable DP stream */
    REG_UPDATE(DP_VID_STREAM_CNTL, DP_VID_STREAM_ENABLE, 0);
-- 
2.17.1


    