Hi Samuel,
Thanks for trying to clean all this up.
One problem below.
Samuel Holland <samuel.holland@xxxxxxxxxx> writes:
> Now that all previously-supported architectures select
> ARCH_HAS_KERNEL_FPU_SUPPORT, this code can depend on that symbol instead
> of the existing list of architectures. It can also take advantage of the
> common kernel-mode FPU API and method of adjusting CFLAGS.
>
> Signed-off-by: Samuel Holland <samuel.holland@xxxxxxxxxx>
...
> 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..b64f917174ca 100644
> --- a/drivers/gpu/drm/amd/display/amdgpu_dm/dc_fpu.c
> +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/dc_fpu.c
> @@ -87,20 +78,9 @@ void dc_fpu_begin(const char *function_name, const int line)
> WARN_ON_ONCE(!in_task());
> preempt_disable();
> depth = __this_cpu_inc_return(fpu_recursion_depth);
> -
> if (depth == 1) {
> -#if defined(CONFIG_X86) || defined(CONFIG_LOONGARCH)
> + BUG_ON(!kernel_fpu_available());
> 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();
Note altivec.
> - else if (!cpu_has_feature(CPU_FTR_FPU_UNAVAILABLE))
> - enable_kernel_fp();
> -#elif defined(CONFIG_ARM64)
> - kernel_neon_begin();
> -#endif
> }
>
> TRACE_DCN_FPU(true, function_name, line, depth);
> diff --git a/drivers/gpu/drm/amd/display/dc/dml/Makefile b/drivers/gpu/drm/amd/display/dc/dml/Makefile
> index ea7d60f9a9b4..5aad0f572ba3 100644
> --- a/drivers/gpu/drm/amd/display/dc/dml/Makefile
> +++ b/drivers/gpu/drm/amd/display/dc/dml/Makefile
> @@ -25,40 +25,8 @@
> # It provides the general basic services required by other DAL
> # subcomponents.
>
> -ifdef CONFIG_X86
> -dml_ccflags-$(CONFIG_CC_IS_GCC) := -mhard-float
> -dml_ccflags := $(dml_ccflags-y) -msse
> -endif
> -
> -ifdef CONFIG_PPC64
> -dml_ccflags := -mhard-float -maltivec
> -endif
And altivec is enabled in the flags there.
That doesn't match your implementation for powerpc in patch 7, which
only deals with float.
I suspect the AMD driver actually doesn't need altivec enabled, but I
don't know that for sure. It compiles without it, but I don't have a GPU
to actually test. I've added Timothy on Cc who added the support for
powerpc to the driver originally, hopefully he has a test system.
Anyway if that's true that it doesn't need altivec we should probably do
a lead-up patch that drops altivec from the AMD driver explicitly, eg.
as below.
cheers
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 6042a5a6a44f..554c39024a40 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
