diff mbox series

drm/amd/display: Allow building DC with clang on LoongArch

Message ID 20241115150225.2812054-1-chenhuacai@loongson.cn (mailing list archive)
State New
Headers show
Series drm/amd/display: Allow building DC with clang on LoongArch | expand

Commit Message

Huacai Chen Nov. 15, 2024, 3:02 p.m. UTC
Clang on LoongArch (18+) appears to be unaffected by the bug causing
excessive stack usage in calculate_bandwidth(). But when building DC_FP
support the stack frame size can be as large as 2816 bytes, which causes
the FRAME_WARN build warnings. So on LoongArch we allow building DC with
clang, but disable DC_FP by default.

The help message is also updated.

Tested-by: Rui Wang <wangrui@loongson.cn>
Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
---
 drivers/gpu/drm/amd/display/Kconfig | 15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

Comments

Alex Deucher Nov. 18, 2024, 3:24 p.m. UTC | #1
Applied.  Thanks.

Alex

On Fri, Nov 15, 2024 at 8:19 PM Huacai Chen <chenhuacai@loongson.cn> wrote:
>
> Clang on LoongArch (18+) appears to be unaffected by the bug causing
> excessive stack usage in calculate_bandwidth(). But when building DC_FP
> support the stack frame size can be as large as 2816 bytes, which causes
> the FRAME_WARN build warnings. So on LoongArch we allow building DC with
> clang, but disable DC_FP by default.
>
> The help message is also updated.
>
> Tested-by: Rui Wang <wangrui@loongson.cn>
> Signed-off-by: Huacai Chen <chenhuacai@loongson.cn>
> ---
>  drivers/gpu/drm/amd/display/Kconfig | 15 ++++++++-------
>  1 file changed, 8 insertions(+), 7 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/display/Kconfig b/drivers/gpu/drm/amd/display/Kconfig
> index df17e79c45c7..11e3f2f3b174 100644
> --- a/drivers/gpu/drm/amd/display/Kconfig
> +++ b/drivers/gpu/drm/amd/display/Kconfig
> @@ -7,20 +7,21 @@ menu "Display Engine Configuration"
>  config DRM_AMD_DC
>         bool "AMD DC - Enable new display engine"
>         default y
> -       depends on BROKEN || !CC_IS_CLANG || ARM64 || RISCV || SPARC64 || X86_64
> +       depends on BROKEN || !CC_IS_CLANG || ARM64 || LOONGARCH || RISCV || SPARC64 || X86_64
>         select SND_HDA_COMPONENT if SND_HDA_CORE
>         # !CC_IS_CLANG: https://github.com/ClangBuiltLinux/linux/issues/1752
> -       select DRM_AMD_DC_FP if ARCH_HAS_KERNEL_FPU_SUPPORT && !(CC_IS_CLANG && (ARM64 || RISCV))
> +       select DRM_AMD_DC_FP if ARCH_HAS_KERNEL_FPU_SUPPORT && !(CC_IS_CLANG && (ARM64 || LOONGARCH || RISCV))
>         help
>           Choose this option if you want to use the new display engine
>           support for AMDGPU. This adds required support for Vega and
>           Raven ASICs.
>
> -         calculate_bandwidth() is presently broken on all !(X86_64 || SPARC64 || ARM64)
> -         architectures built with Clang (all released versions), whereby the stack
> -         frame gets blown up to well over 5k.  This would cause an immediate kernel
> -         panic on most architectures.  We'll revert this when the following bug report
> -         has been resolved: https://github.com/llvm/llvm-project/issues/41896.
> +         calculate_bandwidth() is presently broken on all !(X86_64 || SPARC64 ||
> +         ARM64 || LOONGARCH || RISCV) architectures built with Clang (all released
> +         versions), whereby the stack frame gets blown up to well over 5k.  This
> +         would cause an immediate kernel panic on most architectures.  We'll revert
> +         this when the following bug report has been resolved:
> +         https://github.com/llvm/llvm-project/issues/41896.
>
>  config DRM_AMD_DC_FP
>         def_bool n
> --
> 2.43.5
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/amd/display/Kconfig b/drivers/gpu/drm/amd/display/Kconfig
index df17e79c45c7..11e3f2f3b174 100644
--- a/drivers/gpu/drm/amd/display/Kconfig
+++ b/drivers/gpu/drm/amd/display/Kconfig
@@ -7,20 +7,21 @@  menu "Display Engine Configuration"
 config DRM_AMD_DC
 	bool "AMD DC - Enable new display engine"
 	default y
-	depends on BROKEN || !CC_IS_CLANG || ARM64 || RISCV || SPARC64 || X86_64
+	depends on BROKEN || !CC_IS_CLANG || ARM64 || LOONGARCH || RISCV || SPARC64 || X86_64
 	select SND_HDA_COMPONENT if SND_HDA_CORE
 	# !CC_IS_CLANG: https://github.com/ClangBuiltLinux/linux/issues/1752
-	select DRM_AMD_DC_FP if ARCH_HAS_KERNEL_FPU_SUPPORT && !(CC_IS_CLANG && (ARM64 || RISCV))
+	select DRM_AMD_DC_FP if ARCH_HAS_KERNEL_FPU_SUPPORT && !(CC_IS_CLANG && (ARM64 || LOONGARCH || RISCV))
 	help
 	  Choose this option if you want to use the new display engine
 	  support for AMDGPU. This adds required support for Vega and
 	  Raven ASICs.
 
-	  calculate_bandwidth() is presently broken on all !(X86_64 || SPARC64 || ARM64)
-	  architectures built with Clang (all released versions), whereby the stack
-	  frame gets blown up to well over 5k.  This would cause an immediate kernel
-	  panic on most architectures.  We'll revert this when the following bug report
-	  has been resolved: https://github.com/llvm/llvm-project/issues/41896.
+	  calculate_bandwidth() is presently broken on all !(X86_64 || SPARC64 ||
+	  ARM64 || LOONGARCH || RISCV) architectures built with Clang (all released
+	  versions), whereby the stack frame gets blown up to well over 5k.  This
+	  would cause an immediate kernel panic on most architectures.  We'll revert
+	  this when the following bug report has been resolved:
+	  https://github.com/llvm/llvm-project/issues/41896.
 
 config DRM_AMD_DC_FP
 	def_bool n