linux.git/drivers/gpu/drm/amd/display/dc/dsc, branch master Linux kernel source tree drm/amd/display: Rework YCbCr422 DSC policy 2026-04-17T19:12:02+00:00 Relja Vojvodic Relja.Vojvodic@amd.com 2026-03-20T19:40:25+00:00 ba86f9b5c09aee64923b90b7d7add993fcb34a89 - Reworked YCbCr4:2:2 Native/Simple policy decision making with DSC enabled based on DSC caps and stream signal type Reviewed-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: Relja Vojvodic <Relja.Vojvodic@amd.com> Signed-off-by: Roman Li <roman.li@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
- Reworked YCbCr4:2:2 Native/Simple policy decision making with DSC
enabled based on DSC caps and stream signal type

Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Relja Vojvodic <Relja.Vojvodic@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: enable eDP DSC seamless boot support 2026-03-30T18:57:56+00:00 Mohit Bawa Mohit.Bawa@amd.com 2025-11-05T18:58:35+00:00 add9aee8d889a7ffbff9d5ddbf1f5472a7cbfb82 [Why] VBIOS supports DSC for seamless boot on newer hardware. Reading hardware state allows proper DSC validation without breaking existing boot display. [What] Remove DSC block for boot timing validation and implement hardware state reading to populate DSC configuration from VBIOS-configured state. Enhance dsc_read_state function in DCN401 to read additional DSC parameters. Reviewed-by: Yihan Zhu <yihan.zhu@amd.com> Signed-off-by: Mohit Bawa <Mohit.Bawa@amd.com> Signed-off-by: Chuanyu Tseng <chuanyu.tseng@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[Why]
VBIOS supports DSC for seamless boot on newer hardware.
Reading hardware state allows proper DSC validation without breaking
existing boot display.

[What]
Remove DSC block for boot timing validation and implement hardware state
reading to populate DSC configuration from VBIOS-configured state.
Enhance dsc_read_state function in DCN401 to read additional
DSC parameters.

Reviewed-by: Yihan Zhu <yihan.zhu@amd.com>
Signed-off-by: Mohit Bawa <Mohit.Bawa@amd.com>
Signed-off-by: Chuanyu Tseng <chuanyu.tseng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Revert "drm/amd/display: Rework YCbCr422 DSC policy" 2026-03-30T18:56:26+00:00 Relja Vojvodic Relja.Vojvodic@amd.com 2026-03-17T20:47:07+00:00 246808e7922056594311ad6ca11d31d2d8c27b01 Revert commit 19b79e4f2182 ("drm/amd/display: Rework YCbCr422 DSC policy") Reason for Revert: This commit is causing compliance failures Reviewed-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: Relja Vojvodic <Relja.Vojvodic@amd.com> Signed-off-by: Chuanyu Tseng <chuanyu.tseng@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
Revert commit 19b79e4f2182 ("drm/amd/display: Rework YCbCr422 DSC policy")

Reason for Revert:
This commit is causing compliance failures

Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Relja Vojvodic <Relja.Vojvodic@amd.com>
Signed-off-by: Chuanyu Tseng <chuanyu.tseng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Rework YCbCr422 DSC policy 2026-03-23T18:16:16+00:00 Relja Vojvodic Relja.Vojvodic@amd.com 2026-03-11T21:02:24+00:00 19b79e4f21825b5e61ac9ac6db76327677dd8b6e - Reworked YCbCr4:2:2 Native/Simple policy decision making with DSC enabled based on DSC caps and stream signal type Reviewed-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: Relja Vojvodic <Relja.Vojvodic@amd.com> Signed-off-by: Chuanyu Tseng <chuanyu.tseng@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
- Reworked YCbCr4:2:2 Native/Simple policy decision making with DSC
enabled based on DSC caps and stream signal type

Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Relja Vojvodic <Relja.Vojvodic@amd.com>
Signed-off-by: Chuanyu Tseng <chuanyu.tseng@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Make DSC FGCG a DSC block level function 2026-02-03T21:39:37+00:00 Nicholas Kazlauskas nicholas.kazlauskas@amd.com 2026-01-14T19:55:38+00:00 b8285d2ee73758386252cc3a67839bc463dfa1cc [Why] FGCG shouldn't be called at the DC resource level as part of DSC creation because dc_create is intended for SW init, not HW init, and register access is not guaranteed to work at this phase. [How] Add a set_fgcg function at the DSC interface level. Existing ASIC can continue using the function in DC resource to retain current compatibility but further development should favor calling the function pointer during init_hw (if it exists). Reviewed-by: Dillon Varone <dillon.varone@amd.com> Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Signed-off-by: Wayne Lin <wayne.lin@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[Why]
FGCG shouldn't be called at the DC resource level as part of DSC
creation because dc_create is intended for SW init, not HW init, and
register access is not guaranteed to work at this phase.

[How]
Add a set_fgcg function at the DSC interface level.

Existing ASIC can continue using the function in DC resource to retain
current compatibility but further development should favor calling
the function pointer during init_hw (if it exists).

Reviewed-by: Dillon Varone <dillon.varone@amd.com>
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Signed-off-by: Wayne Lin <wayne.lin@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: fix misspelling of "minimum" in dc_dsc.c 2026-01-20T22:25:59+00:00 Runrun Liu liurunrun@uniontech.com 2026-01-19T08:44:03+00:00 0314df64dd328261215215a201b578ffbd56d3db Fix the typo "miniumum" → "minimum" in a comment in dc_dsc.c. This typo is already listed in scripts/spelling.txt by commit 8c3200265787 ("scripts/spelling.txt: add several more common spelling mistakes"). Suggested-by: Cryolitia PukNgae <cryolitia@uniontech.com> Signed-off-by: Runrun Liu <liurunrun@uniontech.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
Fix the typo "miniumum" → "minimum" in a comment in dc_dsc.c.

This typo is already listed in scripts/spelling.txt by commit
8c3200265787 ("scripts/spelling.txt: add several more common spelling
mistakes").

Suggested-by: Cryolitia PukNgae <cryolitia@uniontech.com>
Signed-off-by: Runrun Liu <liurunrun@uniontech.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: refactor DSC cap calculation for dcn35 2025-11-12T02:54:15+00:00 Mohit Bawa Mohit.Bawa@amd.com 2025-10-23T14:40:41+00:00 d7ef56dbfa2836fd83bdd8a1094b7616d715cc7f why: dcn35 currently uses a hardcoded DSC display clock value which is incorrect for some asic types. Newer DCN versions retrieve dsc display clock from clk_mgr. The same can be done for dcn35. how: Refactor the DSC cap calculation using pre-existing logic. Handle ODM combine requirements in dc_dsc.c. Replace hardcoded display clock with actual value retrieved from clk_mgr. Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com> Reviewed-by: Charlene Liu <charlene.liu@amd.com> Reviewed-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: Mohit Bawa <Mohit.Bawa@amd.com> Signed-off-by: Fangzhi Zuo <jerry.zuo@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
why:
dcn35 currently uses a hardcoded DSC display clock value which is incorrect
for some asic types. Newer DCN versions retrieve dsc display clock from
clk_mgr. The same can be done for dcn35.

how:
Refactor the DSC cap calculation using pre-existing logic.
Handle ODM combine requirements in dc_dsc.c.
Replace hardcoded display clock with actual value retrieved from clk_mgr.

Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Charlene Liu <charlene.liu@amd.com>
Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Mohit Bawa <Mohit.Bawa@amd.com>
Signed-off-by: Fangzhi Zuo <jerry.zuo@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Add more DC HW state info to underflow logging 2025-10-28T13:57:44+00:00 Karen Chen Karen.Chen@amd.com 2025-10-15T15:13:07+00:00 dbf58a9dad4d80286c5c17e199f595eb0dd3be5a [Why] Debugging underflow issues frequently requires knowing the HW state at the time of underflow. To enable capturing this HW state information, interface functions are needed for the various DC HW blocks. [How] This change adds the interface functions to read HW state for the following DC HW blocks: - HUBBUB - HUBP - DPP - MPC - OPP - DSC - OPTC - DCCG Reviewed-by: George Shen <george.shen@amd.com> Signed-off-by: Karen Chen <Karen.Chen@amd.com> Signed-off-by: Wayne Lin <wayne.lin@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[Why]
Debugging underflow issues frequently requires knowing the
HW state at the time of underflow. To enable capturing this
HW state information, interface functions are needed for the
various DC HW blocks.

[How]
This change adds the interface functions to read HW state for
the following DC HW blocks:
- HUBBUB
- HUBP
- DPP
- MPC
- OPP
- DSC
- OPTC
- DCCG

Reviewed-by: George Shen <george.shen@amd.com>
Signed-off-by: Karen Chen <Karen.Chen@amd.com>
Signed-off-by: Wayne Lin <wayne.lin@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Correct slice width calculation for YCbCr420 2025-10-13T18:14:31+00:00 Relja Vojvodic rvojvodi@amd.com 2025-09-17T16:30:51+00:00 81557c96c8a171b5d2500662d4d62f27ab6bad23 [Why] -OVT compliance testing for 5120x2880p300Hz YCbCr420 was failing due to incorrect slice width being calculated [How] -Ensure slice width is divisible by 2 for 420 to comply with spec Reviewed-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: Relja Vojvodic <rvojvodi@amd.com> Signed-off-by: Roman Li <roman.li@amd.com> Tested-by: Dan Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[Why]
-OVT compliance testing for 5120x2880p300Hz YCbCr420 was failing due to
incorrect slice width being calculated

[How]
-Ensure slice width is divisible by 2 for 420 to comply with spec

Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Relja Vojvodic <rvojvodi@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Tested-by: Dan Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
drm/amd/display: Add DSC padding for OVT Support 2025-09-15T21:01:11+00:00 Relja Vojvodic rvojvodi@amd.com 2025-09-04T19:38:24+00:00 edae98a2bdf25d719297f5aa5dfbfc1b4d86bde5 [Why] -Certain OVT timings require DSC configurations which divide the horizontal active unevenly across DSC slices -DSC slices must be even, so padding needs to be added to the active to make this possible -The pixel clock of the HW now needs to be increased to accommodate the extra padded pixels -To keep the line time the same, the blank of the HW timing needs to be increased as well [How] -Calculate h_active padding, h_total padding, and pixel clock based off of the original OVT timing and DSC calculations -Store these values in the pipe and program HW with these modifications -Added general support for cases where DSC slice config does not evenly split the horizontal active by fixing some slice width calculations -Updated PPS calculations for these cases Reviewed-by: Chris Park <chris.park@amd.com> Reviewed-by: Wenjing Liu <wenjing.liu@amd.com> Signed-off-by: Relja Vojvodic <rvojvodi@amd.com> Signed-off-by: Ray Wu <ray.wu@amd.com> Tested-by: Daniel Wheeler <daniel.wheeler@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> 
[Why]
-Certain OVT timings require DSC configurations which divide the
horizontal active unevenly across DSC slices
-DSC slices must be even, so padding needs to be added to the active
to make this possible
-The pixel clock of the HW now needs to be increased to accommodate
the extra padded pixels
-To keep the line time the same, the blank of the HW timing needs to
be increased as well

[How]
-Calculate h_active padding, h_total padding, and pixel clock based
off of the original OVT timing and DSC calculations
-Store these values in the pipe and program HW with these modifications
-Added general support for cases where DSC slice config does not evenly
split the horizontal active by fixing some slice width calculations
-Updated PPS calculations for these cases

Reviewed-by: Chris Park <chris.park@amd.com>
Reviewed-by: Wenjing Liu <wenjing.liu@amd.com>
Signed-off-by: Relja Vojvodic <rvojvodi@amd.com>
Signed-off-by: Ray Wu <ray.wu@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>