kernel/linux.git/drivers/gpu/drm/amd/display/dc/dml, branch v6.18.22

drm/amd/display: Increase DCN35 SR enter/exit latency

2026-03-04T12:21:28+00:00

[ Upstream commit 318917e1d8ecc89f820f4fabf79935f4fed718cd ] [Why & How] On Framework laptops with DDR5 modules, underflow can be observed. It's unclear why it only occurs on specific desktop contents. However, increasing enter/exit latencies by 3us seems to resolve it. Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4463 Reviewed-by: Nicholas Kazlauskas Signed-off-by: Leo Li Signed-off-by: Tom Chung Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org Signed-off-by: Sasha Levin

drm/amd/display: Reduce number of arguments of dcn30's CalculatePrefetchSchedule()

2026-02-11T12:41:49+00:00

[ Upstream commit f54a91f5337cd918eb86cf600320d25b6cfd8209 ] After an innocuous optimization change in clang-22, dml30_ModeSupportAndSystemConfigurationFull() is over the 2048 byte stack limit for display_mode_vba_30.c. drivers/gpu/drm/amd/amdgpu/../display/dc/dml/dcn30/display_mode_vba_30.c:3529:6: warning: stack frame size (2096) exceeds limit (2048) in 'dml30_ModeSupportAndSystemConfigurationFull' [-Wframe-larger-than] 3529 | void dml30_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_lib) | ^ With clang-21, this function was already close to the limit: drivers/gpu/drm/amd/amdgpu/../display/dc/dml/dcn30/display_mode_vba_30.c:3529:6: warning: stack frame size (1912) exceeds limit (1586) in 'dml30_ModeSupportAndSystemConfigurationFull' [-Wframe-larger-than] 3529 | void dml30_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_lib) | ^ CalculatePrefetchSchedule() has a large number of parameters, which must be passed on the stack. Most of the parameters between the two callsites are the same, so they can be accessed through the existing mode_lib pointer, instead of being passed as explicit arguments. Doing this reduces the stack size of dml30_ModeSupportAndSystemConfigurationFull() from 2096 bytes to 1912 bytes with clang-22. Closes: https://github.com/ClangBuiltLinux/linux/issues/2117 Signed-off-by: Nathan Chancellor Signed-off-by: Alex Deucher (cherry picked from commit b20b3fc4210f83089f835cdb91deec4b0778761a) Signed-off-by: Sasha Levin

drm/amd/display: Apply e4479aecf658 to dml

2026-01-17T15:35:13+00:00

commit 70740454377f1ba3ff32f5df4acd965db99d055b upstream. After an innocuous optimization change in clang-22, allmodconfig (which enables CONFIG_KASAN and CONFIG_WERROR) breaks with: drivers/gpu/drm/amd/amdgpu/../display/dc/dml/dcn32/display_mode_vba_32.c:1724:6: error: stack frame size (3144) exceeds limit (3072) in 'dml32_ModeSupportAndSystemConfigurationFull' [-Werror,-Wframe-larger-than] 1724 | void dml32_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_lib) | ^ With clang-21, this function was already pretty close to the existing limit of 3072 bytes. drivers/gpu/drm/amd/amdgpu/../display/dc/dml/dcn32/display_mode_vba_32.c:1724:6: error: stack frame size (2904) exceeds limit (2048) in 'dml32_ModeSupportAndSystemConfigurationFull' [-Werror,-Wframe-larger-than] 1724 | void dml32_ModeSupportAndSystemConfigurationFull(struct display_mode_lib *mode_lib) | ^ A similar situation occurred in dml2, which was resolved by commit e4479aecf658 ("drm/amd/display: Increase sanitizer frame larger than limit when compile testing with clang") by increasing the limit for clang when compile testing with certain sanitizer enabled, so that allmodconfig (an easy testing target) continues to work. Apply that same change to the dml folder to clear up the warning for allmodconfig, unbreaking the build. Closes: https://github.com/ClangBuiltLinux/linux/issues/2135 Signed-off-by: Nathan Chancellor Signed-off-by: Alex Deucher (cherry picked from commit 25314b453cf812150e9951a32007a32bba85707e) Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Fix unsafe uses of kernel mode FPU

2025-10-07T18:09:19+00:00

The point of isolating code that uses kernel mode FPU in separate compilation units is to ensure that even implicit uses of, e.g., SIMD registers for spilling occur only in a context where this is permitted, i.e., from inside a kernel_fpu_begin/end block. This is important on arm64, which uses -mgeneral-regs-only to build all kernel code, with the exception of such compilation units where FP or SIMD registers are expected to be used. Given that the compiler may invent uses of FP/SIMD anywhere in such a unit, none of its code may be accessible from outside a kernel_fpu_begin/end block. This means that all callers into such compilation units must use the DC_FP start/end macros, which must not occur there themselves. For robustness, all functions with external linkage that reside there should call dc_assert_fp_enabled() to assert that the FPU context was set up correctly. Fix this for the DCN35, DCN351 and DCN36 implementations. Cc: Austin Zheng Cc: Jun Lei Cc: Harry Wentland Cc: Leo Li Cc: Rodrigo Siqueira Cc: Alex Deucher Cc: "Christian König" Cc: amd-gfx@lists.freedesktop.org Cc: dri-devel@lists.freedesktop.org Signed-off-by: Ard Biesheuvel Signed-off-by: Alex Deucher Cc: stable@vger.kernel.org Signed-off-by: Alex Deucher

drm/amd/display: Rename header file link.h to link_service.h

2025-09-15T20:57:29+00:00

[WHY] Header file name "link.h" collides with system header when dc is compiled as a user-mode library [WHAT] Rename link.h to link_service.h to avoid name collision Reviewed-by: Alvin Lee Signed-off-by: Wesley Chalmers Signed-off-by: Ray Wu Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Array offset used before range check

2025-08-27T17:57:50+00:00

Consolidating multiple CodeQL Fixes for alerts with rule id: cpp/offset-use-before-range-check Reviewed-by: Joshua Aberback Signed-off-by: Clay King Signed-off-by: Aurabindo Pillai Tested-by: Dan Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Incorrect 'not' operator usage

2025-08-27T17:57:50+00:00

Consolidating multiple CodeQL Fixes for alerts with rule id: cpp/incorrect-not-operator-usage Reviewed-by: Joshua Aberback Signed-off-by: Clay King Signed-off-by: Aurabindo Pillai Tested-by: Dan Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Multiplication result converted to larger type

2025-08-27T17:57:50+00:00

Consolidating multiple CodeQL Fixes for alerts with rule id: cpp/integer-multiplication-cast-to-long Reviewed-by: Joshua Aberback Signed-off-by: Clay King Signed-off-by: Aurabindo Pillai Tested-by: Dan Wheeler Signed-off-by: Alex Deucher

drm/amd/display: replace min/max nesting with clamp()

2025-08-18T21:01:32+00:00

The clamp() macro explicitly expresses the intent of constraining a value within bounds.Therefore, replacing min(max(a, b), c) with clamp(val, lo, hi) can improve code readability. Signed-off-by: Xichao Zhao Reviewed-by: Alex Hung Tested-by: Dan Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Remove redundant semicolons

2025-08-15T17:03:26+00:00

Remove unnecessary semicolons. Fixes: dda4fb85e433 ("drm/amd/display: DML changes for DCN32/321") Signed-off-by: Liao Yuanhong Signed-off-by: Alex Deucher