This is a note to let you know that I've just added the patch titled
drm/amd/display: Adjust downscaling limits for dcn314
to the 6.1-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-adjust-downscaling-limits-for-dcn314.patch
and it can be found in the queue-6.1 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit e4bcbed9ffddd5dd5a8675f99a7d6580494f9645
Author: Daniel Miess <Daniel.Miess@xxxxxxx>
Date: Tue Jan 17 15:45:30 2023 -0500
drm/amd/display: Adjust downscaling limits for dcn314
[ Upstream commit dd2db2dc4bd298f33dea50c80c3c11bee4e3b0a4 ]
[Why]
Lower max_downscale_ratio and ARGB888 downscale factor
to prevent cases where underflow may occur on dcn314
[How]
Set max_downscale_ratio to 400 and ARGB downscale factor
to 250 for dcn314
Reviewed-by: Nicholas Kazlauskas <Nicholas.Kazlauskas@xxxxxxx>
Acked-by: Alex Hung <alex.hung@xxxxxxx>
Signed-off-by: Daniel Miess <Daniel.Miess@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/dcn314/dcn314_resource.c b/drivers/gpu/drm/amd/display/dc/dcn314/dcn314_resource.c
index 9066c511a0529..c80c8c8f51e97 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn314/dcn314_resource.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn314/dcn314_resource.c
@@ -871,8 +871,9 @@ static const struct dc_plane_cap plane_cap = {
},
// 6:1 downscaling ratio: 1000/6 = 166.666
+ // 4:1 downscaling ratio for ARGB888 to prevent underflow during P010 playback: 1000/4 = 250
.max_downscale_factor = {
- .argb8888 = 167,
+ .argb8888 = 250,
.nv12 = 167,
.fp16 = 167
},
@@ -1755,7 +1756,7 @@ static bool dcn314_resource_construct(
pool->base.underlay_pipe_index = NO_UNDERLAY_PIPE;
pool->base.pipe_count = pool->base.res_cap->num_timing_generator;
pool->base.mpcc_count = pool->base.res_cap->num_timing_generator;
- dc->caps.max_downscale_ratio = 600;
+ dc->caps.max_downscale_ratio = 400;
dc->caps.i2c_speed_in_khz = 100;
dc->caps.i2c_speed_in_khz_hdcp = 100;
dc->caps.max_cursor_size = 256;
