This is a note to let you know that I've just added the patch titled
drm/amd/display: Disable seamless boot on 128b/132b encoding
to the 6.8-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
drm-amd-display-disable-seamless-boot-on-128b-132b-e.patch
and it can be found in the queue-6.8 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 809b3791438dee41068abbe562437e9036ebede2
Author: Sung Joon Kim <sungjoon.kim@xxxxxxx>
Date: Thu Apr 18 16:59:36 2024 -0400
drm/amd/display: Disable seamless boot on 128b/132b encoding
[ Upstream commit 6f0c228ed9184287031a66b46a79e5a3d2e73a86 ]
[why]
preOS will not support display mode programming and link training
for UHBR rates.
[how]
If we detect a sink that's UHBR capable, disable seamless boot
Reviewed-by: Anthony Koo <anthony.koo@xxxxxxx>
Acked-by: Wayne Lin <wayne.lin@xxxxxxx>
Signed-off-by: Sung Joon Kim <sungjoon.kim@xxxxxxx>
Tested-by: Daniel Wheeler <daniel.wheeler@xxxxxxx>
Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/amd/display/dc/core/dc.c b/drivers/gpu/drm/amd/display/dc/core/dc.c
index 3c3d613c5f00e..040b5c2a57586 100644
--- a/drivers/gpu/drm/amd/display/dc/core/dc.c
+++ b/drivers/gpu/drm/amd/display/dc/core/dc.c
@@ -1804,6 +1804,9 @@ bool dc_validate_boot_timing(const struct dc *dc,
return false;
}
+ if (link->dpcd_caps.channel_coding_cap.bits.DP_128b_132b_SUPPORTED)
+ return false;
+
if (dc->link_srv->edp_is_ilr_optimization_required(link, crtc_timing)) {
DC_LOG_EVENT_LINK_TRAINING("Seamless boot disabled to optimize eDP link rate\n");
return false;
