diff mbox series

drm/amd/display: Allow building DC with clang on RISC-V

Message ID 20230717222923.3026018-1-samuel.holland@sifive.com
State New
Headers
Series drm/amd/display: Allow building DC with clang on RISC-V |

Commit Message

Samuel Holland July 17, 2023, 10:29 p.m. UTC 
  clang on RISC-V appears to be unaffected by the bug causing excessive
stack usage in calculate_bandwidth(). clang 16 with -fstack-usage
reports a 304 byte stack frame size with CONFIG_ARCH_RV32I, and 512
bytes with CONFIG_ARCH_RV64I.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
---

 drivers/gpu/drm/amd/display/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Nathan Chancellor July 18, 2023, 4:39 p.m. UTC | #1 
On Mon, Jul 17, 2023 at 03:29:23PM -0700, Samuel Holland wrote:
> clang on RISC-V appears to be unaffected by the bug causing excessive
> stack usage in calculate_bandwidth(). clang 16 with -fstack-usage
> reports a 304 byte stack frame size with CONFIG_ARCH_RV32I, and 512
> bytes with CONFIG_ARCH_RV64I.
> 
> Signed-off-by: Samuel Holland <samuel.holland@sifive.com>

I built ARCH=riscv allmodconfig drivers/gpu/drm/amd/amdgpu/ (confirming
that CONFIG_DRM_AMD_DC gets enabled) with LLVM 11 through 17 with and
without CONFIG_KASAN=y and I never saw the -Wframe-larger-than instance
that this was disabled for, so I agree.

Reviewed-by: Nathan Chancellor <nathan@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>

> 
>  drivers/gpu/drm/amd/display/Kconfig | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/gpu/drm/amd/display/Kconfig b/drivers/gpu/drm/amd/display/Kconfig
> index bf0a655d009e..901d1961b739 100644
> --- a/drivers/gpu/drm/amd/display/Kconfig
> +++ b/drivers/gpu/drm/amd/display/Kconfig
> @@ -5,7 +5,7 @@ menu "Display Engine Configuration"
>  config DRM_AMD_DC
>  	bool "AMD DC - Enable new display engine"
>  	default y
> -	depends on BROKEN || !CC_IS_CLANG || X86_64 || SPARC64 || ARM64
> +	depends on BROKEN || !CC_IS_CLANG || ARM64 || 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 (X86 || LOONGARCH || (PPC64 && ALTIVEC) || (ARM64 && KERNEL_MODE_NEON && !CC_IS_CLANG))
> -- 
> 2.40.1
>
Alex Deucher July 19, 2023, 12:54 p.m. UTC | #2 
Applied.  Thanks!

On Tue, Jul 18, 2023 at 12:40 PM Nathan Chancellor <nathan@kernel.org> wrote:
>
> On Mon, Jul 17, 2023 at 03:29:23PM -0700, Samuel Holland wrote:
> > clang on RISC-V appears to be unaffected by the bug causing excessive
> > stack usage in calculate_bandwidth(). clang 16 with -fstack-usage
> > reports a 304 byte stack frame size with CONFIG_ARCH_RV32I, and 512
> > bytes with CONFIG_ARCH_RV64I.
> >
> > Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
>
> I built ARCH=riscv allmodconfig drivers/gpu/drm/amd/amdgpu/ (confirming
> that CONFIG_DRM_AMD_DC gets enabled) with LLVM 11 through 17 with and
> without CONFIG_KASAN=y and I never saw the -Wframe-larger-than instance
> that this was disabled for, so I agree.
>
> Reviewed-by: Nathan Chancellor <nathan@kernel.org>
> Tested-by: Nathan Chancellor <nathan@kernel.org>
>
> >
> >  drivers/gpu/drm/amd/display/Kconfig | 2 +-
> >  1 file changed, 1 insertion(+), 1 deletion(-)
> >
> > diff --git a/drivers/gpu/drm/amd/display/Kconfig b/drivers/gpu/drm/amd/display/Kconfig
> > index bf0a655d009e..901d1961b739 100644
> > --- a/drivers/gpu/drm/amd/display/Kconfig
> > +++ b/drivers/gpu/drm/amd/display/Kconfig
> > @@ -5,7 +5,7 @@ menu "Display Engine Configuration"
> >  config DRM_AMD_DC
> >       bool "AMD DC - Enable new display engine"
> >       default y
> > -     depends on BROKEN || !CC_IS_CLANG || X86_64 || SPARC64 || ARM64
> > +     depends on BROKEN || !CC_IS_CLANG || ARM64 || 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 (X86 || LOONGARCH || (PPC64 && ALTIVEC) || (ARM64 && KERNEL_MODE_NEON && !CC_IS_CLANG))
> > --
> > 2.40.1
> >
diff mbox series

Patch

diff --git a/drivers/gpu/drm/amd/display/Kconfig b/drivers/gpu/drm/amd/display/Kconfig
index bf0a655d009e..901d1961b739 100644
--- a/drivers/gpu/drm/amd/display/Kconfig
+++ b/drivers/gpu/drm/amd/display/Kconfig
@@ -5,7 +5,7 @@  menu "Display Engine Configuration"
 config DRM_AMD_DC
 	bool "AMD DC - Enable new display engine"
 	default y
-	depends on BROKEN || !CC_IS_CLANG || X86_64 || SPARC64 || ARM64
+	depends on BROKEN || !CC_IS_CLANG || ARM64 || 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 (X86 || LOONGARCH || (PPC64 && ALTIVEC) || (ARM64 && KERNEL_MODE_NEON && !CC_IS_CLANG))