linux-toradex.git/drivers/gpu/drm/amd/display/dc/resource/dcn20, branch master

drm/amd/display: Fix signed/unsigned comparison mismatches

2026-05-11T20:10:20+00:00

[Why]
Address signed/unsigned comparison warnings in DC paths
to keep builds warning-clean and improve type safety at comparison boundaries.
Most warnings came from signed loop/index temporaries compared against unsigned
counters (for example pipe_count, num_states, and resource-cap counters), plus a
small number of mixed signed/unsigned checks in writeback and clock-related assertions.

[How]
Aligned iterator and temporary variable types with the semantic type of the compared
bounds. Used unsigned indices for loops bounded by unsigned counters, and retained signed
types where values are semantically signed (for example arithmetic with sentinel or signed
intermediate values). Where mixed signed/unsigned comparisons are intentional, applied
explicit boundary casts or split assertions (for example non-negative signed-cap
checks before unsigned comparisons) instead of broad type changes.

No functional behavior changes are intended; this is a warning-resolution and
type-alignment cleanup.

Reviewed-by: Dillon Varone 
Signed-off-by: Gaghik Khachatrian 
Signed-off-by: James Lin 
Tested-by: Daniel Wheeler 
Signed-off-by: Alex Deucher

drm/amd/display: Fix implicit narrowing conversion warnings

2026-04-17T19:41:15+00:00

[Why]
Multiple display source files contain implicit narrowing
conversions when assigning wider integer types (int, uint32_t)
to narrower fields (uint8_t, uint16_t) at hardware register,
protocol, and storage boundaries. These conversions are
intentional but undocumented, and accompanying runtime assertions
add noise without providing compile-time safety.

[How]
Add explicit casts at all intentional narrowing boundaries across
display source files. Use narrower loop variable types where loop
bounds guarantee safe range. Remove runtime assertions paired
with narrowing casts, inline single-use intermediate variables,
and revert block scopes and braces introduced solely to contain
those assertions.

Reviewed-by: Dillon Varone 
Signed-off-by: Gaghik Khachatrian 
Signed-off-by: Chenyu Chen 
Signed-off-by: Alex Deucher

Merge v7.0-rc7 into drm-next

2026-04-07T10:36:31+00:00

Thomas Zimmermann needs 2f42c1a61616 ("drm/ast: dp501: Fix
initialization of SCU2C") for drm-misc-next.

Conflicts:
- drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c

Just between e927b36ae18b ("drm/amd/display: Fix NULL pointer
dereference in dcn401_init_hw()") and it's cherry-pick that confused
git.

- drivers/gpu/drm/amd/pm/swsmu/smu11/smu_v11_0.c

Deleted in 6b0a6116286e ("drm/amd/pm: Unify version check in SMUv11")
but some cherry-picks confused git. Same for v12/v14.

Signed-off-by: Simona Vetter

drm/amd/display: Wire up dcn10_dio_construct() for all pre-DCN401 generations

2026-04-02T19:24:13+00:00

Description:
 - Commit b82f0759346617b2 ("drm/amd/display: Migrate DIO registers access
   from hwseq to dio component") moved DIO_MEM_PWR_CTRL register access
   behind the new dio abstraction layer but only created the dio object for
   DCN 4.01. On all other generations (DCN 10/20/21/201/30/301/302/303/
   31/314/315/316/32/321/35/351/36), the dio pointer is NULL, causing the
   register write to be silently skipped.

   This results in AFMT HDMI memory not being powered on during init_hw,
   which can cause HDMI audio failures and display issues on affected
   hardware including Renoir/Cezanne (DCN 2.1) APUs that use dcn10_init_hw.

   Call dcn10_dio_construct() in each older DCN generation's resource.c
   to create the dio object, following the same pattern as DCN 4.01. This
   ensures the dio pointer is non-NULL and the mem_pwr_ctrl callback works
   through the dio abstraction for all DCN generations.

Fixes: b82f07593466 ("drm/amd/display: Migrate DIO registers access from hwseq to dio component.")
Reviewed-by: Ivan Lipski 
Signed-off-by: Ionut Nechita 
Signed-off-by: Alex Deucher

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: Don't set 4to1MPC config dynamically

2026-03-30T18:52:56+00:00

We were previously modifying the global dc->config.enable_4to1MPC
dynamically. These variables are meant as global configs, not to
by dynamically modified. Modifying them dynamically prevents us
from enabling/disabling functionality for debug purposes and can
easily lead to bad things since we're not operating on the current
state but on DC-wide variables.

Instead we should look at the existing split4mpc decision in
dcn20_validate_apply_split_flags and make the decision there,
if the global config.enable_4to1MPC is set to true for the
DCN version we're running.

This fixes corruption that is observed when running a new IGT
kms_colorop test for color-space-conversion that uses a
YUV plane and outputs to a writeback connector.

Co-developed by Claude Sonnet 4.5.

Assisted-by: Claude:claude-sonnet-4.5
Reviewed-by: Nicholas Kazlauskas 
Signed-off-by: Harry Wentland 
Signed-off-by: Chuanyu Tseng 
Signed-off-by: Alex Deucher

drm/amd/display: Query DC for gfx handling when setting linear tiling

2026-03-17T14:36:06+00:00

[Why]
Post-driver cases always use linear tiling yet gfx handling for this
case is improper, allowing for incorrect gfx structs to be populated and
used.

[How]
Query DC for the apporpriate linear tiling mode and populate the DCN
specific gfx version structs.

Reviewed-by: Dillon Varone 
Signed-off-by: Nicholas Carbones 
Signed-off-by: Chuanyu Tseng 
Tested-by: Dan Wheeler 
Signed-off-by: Alex Deucher

drm/amd/display: Clean up unused code

2026-03-11T17:58:06+00:00

[WHAT]
Silence warning by cleaning up unused code.

Reviewed-by: Dillon Varone 
Signed-off-by: Clay King 
Signed-off-by: Alex Hung 
Tested-by: Dan Wheeler 
Signed-off-by: Alex Deucher

Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses

2026-02-22T16:26:33+00:00

Conversion performed via this Coccinelle script:

  // SPDX-License-Identifier: GPL-2.0-only
  // Options: --include-headers-for-types --all-includes --include-headers --keep-comments
  virtual patch

  @gfp depends on patch && !(file in "tools") && !(file in "samples")@
  identifier ALLOC = {kmalloc_obj,kmalloc_objs,kmalloc_flex,
 		    kzalloc_obj,kzalloc_objs,kzalloc_flex,
		    kvmalloc_obj,kvmalloc_objs,kvmalloc_flex,
		    kvzalloc_obj,kvzalloc_objs,kvzalloc_flex};
  @@

  	ALLOC(...
  -		, GFP_KERNEL
  	)

  $ make coccicheck MODE=patch COCCI=gfp.cocci

Build and boot tested x86_64 with Fedora 42's GCC and Clang:

Linux version 6.19.0+ (user@host) (gcc (GCC) 15.2.1 20260123 (Red Hat 15.2.1-7), GNU ld version 2.44-12.fc42) #1 SMP PREEMPT_DYNAMIC 1970-01-01
Linux version 6.19.0+ (user@host) (clang version 20.1.8 (Fedora 20.1.8-4.fc42), LLD 20.1.8) #1 SMP PREEMPT_DYNAMIC 1970-01-01

Signed-off-by: Kees Cook 
Signed-off-by: Linus Torvalds