lwn.git/drivers/gpu/drm/amd/display/dc/resource/dce100, branch master

drm/amd/display: Fixed Silence complier warnings in dc

2026-03-30T19:12:15+00:00

[Why] Resolve compiler warnings by marking unused parameters explicitly. [How] In .c and .h function definitions, keep parameter names in signatures and add a line with `(void)param;` in function body Preserved function signatures and avoids breaking code paths that may reference the parameter under conditional compilation. Reviewed-by: Dillon Varone Reviewed-by: Austin Zheng Signed-off-by: Gaghik Khachatrian Signed-off-by: Chuanyu Tseng Signed-off-by: Alex Deucher

drm/amd/display: Fix Silence signed/unsighed mismatch warning in dc

2026-03-30T18:55:17+00:00

[Why] Implicit signed-to-unsigned conversions caused compiler warnings in DC paths. [How] Added explicit (unsigned int)/(uint32_t) casts for sentinel -1 assignments and IRQ ~MASK initializers, with small cast alignment in logging/DPCD code. Functionality and behavior is unchanged; only type intent is explicit. Reviewed-by: Dillon Varone Signed-off-by: Gaghik Khachatrian Signed-off-by: Chuanyu Tseng Signed-off-by: Alex Deucher

drm/amd/display: Fix DCE LVDS handling

2026-03-24T17:34:32+00:00

LVDS does not use an HPD pin so it may be invalid. Handle this case correctly in link encoder creation. Fixes: 7c8fb3b8e9ba ("drm/amd/display: Add hpd_source index check for DCE60/80/100/110/112/120 link encoders") Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/5012 Cc: Srinivasan Shanmugam Cc: Roman Li Reviewed-by: Roman Li Reviewed-by: Srinivasan Shanmugam Signed-off-by: Alex Deucher

Convert more 'alloc_obj' cases to default GFP_KERNEL arguments

2026-02-22T04:03:00+00:00

This converts some of the visually simpler cases that have been split over multiple lines. I only did the ones that are easy to verify the resulting diff by having just that final GFP_KERNEL argument on the next line. Somebody should probably do a proper coccinelle script for this, but for me the trivial script actually resulted in an assertion failure in the middle of the script. I probably had made it a bit _too_ trivial. So after fighting that far a while I decided to just do some of the syntactically simpler cases with variations of the previous 'sed' scripts. The more syntactically complex multi-line cases would mostly really want whitespace cleanup anyway. Signed-off-by: Linus Torvalds

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

drm/amd/display: Remove unneeded DAC link encoder register

2026-02-19T17:16:12+00:00

Not needed anymore since we use the VBIOS function. Signed-off-by: Timur Kristóf Tested-by: Mauro Rossi Reviewed-by: Alex Hung Signed-off-by: Alex Deucher

drm/amd/display: Set CRTC source for DAC using registers

2026-02-19T17:16:12+00:00

Apparently the VBIOS SelectCRTC_Source function overwrites a few registers (such as FMT_*) which DC writes in a different place, which can cause problems. Instead of using the SelectCRTC_Source function from the VBIOS, use the DAC_SOURCE_SELECT register directly, similarly to how it is done for digital link encoders. Fixes: 3be26d81b150 ("drm/amd/display: Support DAC in dce110_hwseq") Signed-off-by: Timur Kristóf Tested-by: Mauro Rossi Reviewed-by: Alex Hung Signed-off-by: Alex Deucher

drm/amd/display: Only use analog stream encoder with analog engine

2026-02-18T15:41:34+00:00

Some GPUs have analog connectors that work with a DP bridge chip and don't actually have an internal DAC: Those should not use the analog stream encoders. Fixes: 5834c33fd3f6 ("drm/amd/display: Add concept of analog encoders (v2)") Signed-off-by: Timur Kristóf Reviewed-by: Alex Hung Signed-off-by: Alex Deucher

drm/amd/display: Only use analog link encoder with analog engine

2026-02-18T15:41:34+00:00

Some GPUs have analog connectors that work with a DP bridge chip and don't actually have an internal DAC: Those should not use the analog link encoder code path. Fixes: 0fbe321a93ce ("drm/amd/display: Implement DCE analog link encoders (v2)") Signed-off-by: Timur Kristóf Reviewed-by: Alex Hung Signed-off-by: Alex Deucher