drm/amd/display: Init dispclk from bootup clock for DCN314

Browse source

[ Upstream commit f082daf08f ]

[Why]
Driver does not pick up and save vbios's clocks during init clocks,
the dispclk in clk_mgr will keep 0 until the first update clocks.
In some cases, OS changes the timing in the second set mode
(lower the pixel clock), causing the driver to lower the dispclk
in prepare bandwidth, which is illegal and causes grey screen.

[How]
1. Dump and save the vbios's clocks, and init the dispclk in
dcn314_init_clocks.
2. Fix the condition in dcn314_update_clocks, regarding a 0kHz value.

Reviewed-by: Charlene Liu <charlene.liu@amd.com>
Signed-off-by: Lo-an Chen <lo-an.chen@amd.com>
Signed-off-by: Ivan Lipski <ivan.lipski@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

...

This commit is contained in:

Lo-an Chen 2025-08-25 18:16:24 +08:00 • committed by Greg Kroah-Hartman

parent 5949255c58

commit 0b9cb68d1a

3 changed files with 143 additions and 5 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

142

drivers/gpu/drm/amd/display/dc/clk_mgr/dcn314/dcn314_clk_mgr.c

View file

5

drivers/gpu/drm/amd/display/dc/clk_mgr/dcn314/dcn314_clk_mgr.h

View file

1

drivers/gpu/drm/amd/display/dc/resource/dcn314/dcn314_resource.c

View file