Re: [PATCH v4 12/15] drm/amd/display: Only use hard-float, not altivec on powerpc

From: Harry Wentland
Date: Tue Apr 30 2024 - 13:29:04 EST


On 2024-03-29 03:18, Samuel Holland wrote:
> From: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
>
> The compiler flags enable altivec, but that is not required; hard-float
> is sufficient for the code to build and function.
>
> Drop altivec from the compiler flags and adjust the enable/disable code
> to only enable FPU use.
>
> Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
> Acked-by: Alex Deucher <alexander.deucher@xxxxxxx>
> Signed-off-by: Samuel Holland <samuel.holland@xxxxxxxxxx>

Acked-by: Harry Wentland <harry.wentland@xxxxxxx>

Harry

> ---
>
> (no changes since v2)
>
> Changes in v2:
> - New patch for v2
>
> drivers/gpu/drm/amd/display/amdgpu_dm/dc_fpu.c | 12 ++----------
> drivers/gpu/drm/amd/display/dc/dml/Makefile | 2 +-
> drivers/gpu/drm/amd/display/dc/dml2/Makefile | 2 +-
> 3 files changed, 4 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/dc_fpu.c b/drivers/gpu/drm/amd/display/amdgpu_dm/dc_fpu.c
> index 4ae4720535a5..0de16796466b 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/dc_fpu.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/dc_fpu.c
> @@ -92,11 +92,7 @@ void dc_fpu_begin(const char *function_name, const int line)
> #if defined(CONFIG_X86) || defined(CONFIG_LOONGARCH)
> kernel_fpu_begin();
> #elif defined(CONFIG_PPC64)
> - if (cpu_has_feature(CPU_FTR_VSX_COMP))
> - enable_kernel_vsx();
> - else if (cpu_has_feature(CPU_FTR_ALTIVEC_COMP))
> - enable_kernel_altivec();
> - else if (!cpu_has_feature(CPU_FTR_FPU_UNAVAILABLE))
> + if (!cpu_has_feature(CPU_FTR_FPU_UNAVAILABLE))
> enable_kernel_fp();
> #elif defined(CONFIG_ARM64)
> kernel_neon_begin();
> @@ -125,11 +121,7 @@ void dc_fpu_end(const char *function_name, const int line)
> #if defined(CONFIG_X86) || defined(CONFIG_LOONGARCH)
> kernel_fpu_end();
> #elif defined(CONFIG_PPC64)
> - if (cpu_has_feature(CPU_FTR_VSX_COMP))
> - disable_kernel_vsx();
> - else if (cpu_has_feature(CPU_FTR_ALTIVEC_COMP))
> - disable_kernel_altivec();
> - else if (!cpu_has_feature(CPU_FTR_FPU_UNAVAILABLE))
> + if (!cpu_has_feature(CPU_FTR_FPU_UNAVAILABLE))
> disable_kernel_fp();
> #elif defined(CONFIG_ARM64)
> kernel_neon_end();
> diff --git a/drivers/gpu/drm/amd/display/dc/dml/Makefile b/drivers/gpu/drm/amd/display/dc/dml/Makefile
> index c4a5efd2dda5..59d3972341d2 100644
> --- a/drivers/gpu/drm/amd/display/dc/dml/Makefile
> +++ b/drivers/gpu/drm/amd/display/dc/dml/Makefile
> @@ -31,7 +31,7 @@ dml_ccflags := $(dml_ccflags-y) -msse
> endif
>
> ifdef CONFIG_PPC64
> -dml_ccflags := -mhard-float -maltivec
> +dml_ccflags := -mhard-float
> endif
>
> ifdef CONFIG_ARM64
> diff --git a/drivers/gpu/drm/amd/display/dc/dml2/Makefile b/drivers/gpu/drm/amd/display/dc/dml2/Makefile
> index acff3449b8d7..7b51364084b5 100644
> --- a/drivers/gpu/drm/amd/display/dc/dml2/Makefile
> +++ b/drivers/gpu/drm/amd/display/dc/dml2/Makefile
> @@ -30,7 +30,7 @@ dml2_ccflags := $(dml2_ccflags-y) -msse
> endif
>
> ifdef CONFIG_PPC64
> -dml2_ccflags := -mhard-float -maltivec
> +dml2_ccflags := -mhard-float
> endif
>
> ifdef CONFIG_ARM64