This is a note to let you know that I've just added the patch titled
drm/amd/display: Disable DMCUB timeout for DCN35
to the 6.10-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-dmcub-timeout-for-dcn35.patch
and it can be found in the queue-6.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit 6cece8d64a7f95f4abc6ed73aa8f45c0a355c77c
Author: Nicholas Kazlauskas <nicholas.kazlauskas@xxxxxxx>
Date: Wed May 29 12:12:09 2024 -0400
drm/amd/display: Disable DMCUB timeout for DCN35
[ Upstream commit 7c70e60fbf4bff1123f0e8d5cb1ae71df6164d7f ]
[Why]
DMCUB can intermittently take longer than expected to process commands.
Old ASIC policy was to continue while logging a diagnostic error - which
works fine for ASIC without IPS, but with IPS this could lead to a race
condition where we attempt to access DCN state while it's inaccessible,
leading to a system hang when the NIU port is not disabled or register
accesses that timeout and the display configuration in an undefined
state.
[How]
We need to investigate why these accesses take longer than expected, but
for now we should disable the timeout on DCN35 to avoid this race
condition. Since the waits happen only at lower interrupt levels the
risk of taking too long at higher IRQ and causing a system watchdog
timeout are minimal.
Reviewed-by: Ovidiu Bunea <ovidiu.bunea@xxxxxxx>
Acked-by: Zaeem Mohamed <zaeem.mohamed@xxxxxxx>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@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/resource/dcn35/dcn35_resource.c b/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c
index 28c459907698..915d68cc04e9 100644
--- a/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/resource/dcn35/dcn35_resource.c
@@ -785,6 +785,7 @@ static const struct dc_debug_options debug_defaults_drv = {
.ips2_entry_delay_us = 800,
.disable_dmub_reallow_idle = false,
.static_screen_wait_frames = 2,
+ .disable_timeout = true,
};
static const struct dc_panel_config panel_config_defaults = {
