powerpc: implement ARCH_HAS_KERNEL_FPU_SUPPORT

PowerPC provides an equivalent to the common kernel-mode FPU API, but in a
different header and using different function names.  The PowerPC API also
requires a non-preemptible context.  Add a wrapper header, and export the
CFLAGS adjustments.

Link: https://lkml.kernel.org/r/20240329072441.591471-9-samuel.holland@sifive.com
Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Christian König <christian.koenig@amd.com> 
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Borislav Petkov (AMD) <bp@alien8.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nicolas Schier <nicolas@fjasle.eu>
Cc: Palmer Dabbelt <palmer@rivosinc.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: WANG Xuerui <git@xen0n.name>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
This commit is contained in:
Samuel Holland 2024-03-29 00:18:23 -07:00 committed by Andrew Morton
parent 372f662345
commit 01db473e1a
3 changed files with 33 additions and 1 deletions

View file

@ -137,6 +137,7 @@ config PPC
select ARCH_HAS_GCOV_PROFILE_ALL
select ARCH_HAS_HUGEPD if HUGETLB_PAGE
select ARCH_HAS_KCOV
select ARCH_HAS_KERNEL_FPU_SUPPORT if PPC_FPU
select ARCH_HAS_MEMBARRIER_CALLBACKS
select ARCH_HAS_MEMBARRIER_SYNC_CORE
select ARCH_HAS_MEMREMAP_COMPAT_ALIGN if PPC_64S_HASH_MMU

View file

@ -149,6 +149,9 @@ CFLAGS-$(CONFIG_PPC32) += $(call cc-option, $(MULTIPLEWORD))
CFLAGS-$(CONFIG_PPC32) += $(call cc-option,-mno-readonly-in-sdata)
CC_FLAGS_FPU := $(call cc-option,-mhard-float)
CC_FLAGS_NO_FPU := $(call cc-option,-msoft-float)
ifdef CONFIG_FUNCTION_TRACER
ifdef CONFIG_ARCH_USING_PATCHABLE_FUNCTION_ENTRY
KBUILD_CPPFLAGS += -DCC_USING_PATCHABLE_FUNCTION_ENTRY
@ -170,7 +173,7 @@ asinstr := $(call as-instr,lis 9$(comma)foo@high,-DHAVE_AS_ATHIGH=1)
KBUILD_CPPFLAGS += -I $(srctree)/arch/powerpc $(asinstr)
KBUILD_AFLAGS += $(AFLAGS-y)
KBUILD_CFLAGS += $(call cc-option,-msoft-float)
KBUILD_CFLAGS += $(CC_FLAGS_NO_FPU)
KBUILD_CFLAGS += $(CFLAGS-y)
CPP = $(CC) -E $(KBUILD_CFLAGS)

View file

@ -0,0 +1,28 @@
/* SPDX-License-Identifier: GPL-2.0-only */
/*
* Copyright (C) 2023 SiFive
*/
#ifndef _ASM_POWERPC_FPU_H
#define _ASM_POWERPC_FPU_H
#include <linux/preempt.h>
#include <asm/cpu_has_feature.h>
#include <asm/switch_to.h>
#define kernel_fpu_available() (!cpu_has_feature(CPU_FTR_FPU_UNAVAILABLE))
static inline void kernel_fpu_begin(void)
{
preempt_disable();
enable_kernel_fp();
}
static inline void kernel_fpu_end(void)
{
disable_kernel_fp();
preempt_enable();
}
#endif /* ! _ASM_POWERPC_FPU_H */