When building ARCH=x86_64 allmodconfig with clang, which will typically
have sanitizers enabled, there is a warning about a large stack frame.
drivers/gpu/drm/amd/amdgpu/../display/dc/dml2/display_mode_core.c:6265:13: error: stack frame size (2520) exceeds limit (2048) in 'dml_prefetch_check' [-Werror,-Wframe-larger-than]
6265 | static void dml_prefetch_check(struct display_mode_lib_st *mode_lib)
| ^
1 error generated.
Notably, GCC 13.2.0 does not do too much of a better job, as it is right
at the current limit of 2048 (and others have reported being over with
older GCC versions):
drivers/gpu/drm/amd/amdgpu/../display/dc/dml2/display_mode_core.c: In function 'dml_prefetch_check':
drivers/gpu/drm/amd/amdgpu/../display/dc/dml2/display_mode_core.c:6705:1: error: the frame size of 2048 bytes is larger than 1800 bytes [-Werror=frame-larger-than=]
6705 | }
| ^
In the past, these warnings have been avoided by reducing the number of
parameters to various functions so that not as many arguments need to be
passed on the stack. However, these patches take a good amount of effort
to write despite being mechanical due to code structure and complexity
and they are never carried forward to new generations of the code so
that effort has to be expended every new hardware generation, which
becomes harder to justify as time goes on.
To avoid having a noticeable or lengthy breakage in all{mod,yes}config,
which are easy testing targets that have -Werror enabled, increase the
limit for configurations that have KASAN or KCSAN enabled by 50% so that
cases of extremely poor code generation can still be caught while not
breaking the majority of builds. CONFIG_KMSAN also causes high stack
usage but the frame limit is already set to zero when it is enabled,
which is accounted for by the check for CONFIG_FRAME_WARN=0 in the dml2
Makefile.
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
display_mode_code.c is unconditionally built with
-Wframe-larger-than=2048, which causes warnings even when
CONFIG_FRAME_WARN has been set to 0, which should show no warnings.
Use the existing $(frame_warn_flag) variable, which handles this
situation. This is basically commit 25f178bbd0 ("drm/amd/display:
Respect CONFIG_FRAME_WARN=0 in dml Makefile") but for DML2.
Fixes: 7966f319c6 ("drm/amd/display: Introduce DML2")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
DC is transitioning from DML to DML2, and this commit introduces all the
required changes for some of the already available ASICs and adds the
required code infra to support new ASICs under DML2. DML2 is also a
generated code that provides better mode verification and programming
models for software/hardware, and it enables a better way to create
validation tools. This version is more like a middle step to the
complete transition to the DML2 version.
Changes since V1:
- Alex: Fix typos
Changes since V2:
- Update DC includes
Changes since V3:
- Fix 32 bit compilation issues on x86
Changes since V4:
- Avoid compilation of DML2 on some not supported 32-bit architecture
- Update commit message
Co-developed-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Co-developed-by: Roman Li <roman.li@amd.com>
Signed-off-by: Roman Li <roman.li@amd.com>
Signed-off-by: Qingqing Zhuo <Qingqing.Zhuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>