[PATCH AUTOSEL 6.1 15/22] drm/amd/display: Blocking invalid 420 modes on HDMI TMDS for DCN31

From: Sasha Levin
Date: Fri Sep 08 2023 - 15:36:39 EST


From: Leo Chen <sancchen@xxxxxxx>

[ Upstream commit 026a71babf48efb6b9884a3a66fa31aec9e1ea54 ]

[Why & How]
HDMI TMDS does not have ODM support. Filtering 420 modes that
exceed the 4096 FMT limitation on DCN31 will resolve
intermittent corruptions issues.

Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx>
Acked-by: Tom Chung <chiahsuan.chung@xxxxxxx>
Signed-off-by: Leo Chen <sancchen@xxxxxxx>
Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
.../gpu/drm/amd/display/dc/dml/dcn31/display_mode_vba_31.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dml/dcn31/display_mode_vba_31.c b/drivers/gpu/drm/amd/display/dc/dml/dcn31/display_mode_vba_31.c
index ebc04b72b284b..9c84561ff3bc4 100644
--- a/drivers/gpu/drm/amd/display/dc/dml/dcn31/display_mode_vba_31.c
+++ b/drivers/gpu/drm/amd/display/dc/dml/dcn31/display_mode_vba_31.c
@@ -4133,7 +4133,9 @@ void dml31_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_l
}
if (v->OutputFormat[k] == dm_420 && v->HActive[k] > DCN31_MAX_FMT_420_BUFFER_WIDTH
&& v->ODMCombineEnablePerState[i][k] != dm_odm_combine_mode_4to1) {
- if (v->HActive[k] / 2 > DCN31_MAX_FMT_420_BUFFER_WIDTH) {
+ if (v->Output[k] == dm_hdmi) {
+ FMTBufferExceeded = true;
+ } else if (v->HActive[k] / 2 > DCN31_MAX_FMT_420_BUFFER_WIDTH) {
v->ODMCombineEnablePerState[i][k] = dm_odm_combine_mode_4to1;
v->PlaneRequiredDISPCLK = v->PlaneRequiredDISPCLKWithODMCombine4To1;

--
2.40.1