Commit 71883ae3 authored by Samuel Holland's avatar Samuel Holland Committed by Andrew Morton
Browse files

arm64: implement ARCH_HAS_KERNEL_FPU_SUPPORT 

arm64 provides an equivalent to the common kernel-mode FPU API, but in a
different header and using different function names.  Add a wrapper
header, and export CFLAGS adjustments as found in lib/raid6/Makefile.

Link: https://lkml.kernel.org/r/20240329072441.591471-5-samuel.holland@sifive.com


Signed-off-by: default avatarSamuel Holland <samuel.holland@sifive.com>
Reviewed-by: default avatarChristoph Hellwig <hch@lst.de>
Acked-by: default avatarChristian 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: Michael Ellerman <mpe@ellerman.id.au>
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: default avatarAndrew Morton <akpm@linux-foundation.org>
parent c4162431

arch/arm64/Kconfig

+1 −0
Original line number Diff line number Diff line
@@ -30,6 +30,7 @@ config ARM64 
	select ARCH_HAS_GCOV_PROFILE_ALL

	select ARCH_HAS_GIGANTIC_PAGE

	select ARCH_HAS_KCOV

	select ARCH_HAS_KERNEL_FPU_SUPPORT if KERNEL_MODE_NEON

	select ARCH_HAS_KEEPINITRD

	select ARCH_HAS_MEMBARRIER_SYNC_CORE

	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS

arch/arm64/Makefile

+8 −1
Original line number Diff line number Diff line
@@ -36,7 +36,14 @@ ifeq ($(CONFIG_BROKEN_GAS_INST),y) 
$(warning Detected assembler with broken .inst; disassembly will be unreliable)

endif



KBUILD_CFLAGS	+= -mgeneral-regs-only	\

# The GCC option -ffreestanding is required in order to compile code containing

# ARM/NEON intrinsics in a non C99-compliant environment (such as the kernel)

CC_FLAGS_FPU	:= -ffreestanding

# Enable <arm_neon.h>

CC_FLAGS_FPU	+= -isystem $(shell $(CC) -print-file-name=include)

CC_FLAGS_NO_FPU	:= -mgeneral-regs-only



KBUILD_CFLAGS	+= $(CC_FLAGS_NO_FPU) \

		   $(compat_vdso) $(cc_has_k_constraint)

KBUILD_CFLAGS	+= $(call cc-disable-warning, psabi)

KBUILD_AFLAGS	+= $(compat_vdso)

arch/arm64/include/asm/fpu.h

0 → 100644
+15 −0
Original line number Diff line number Diff line 
/* SPDX-License-Identifier: GPL-2.0-only */

/*

 * Copyright (C) 2023 SiFive

 */



#ifndef __ASM_FPU_H

#define __ASM_FPU_H



#include <asm/neon.h>



#define kernel_fpu_available()	cpu_has_neon()

#define kernel_fpu_begin()	kernel_neon_begin()

#define kernel_fpu_end()	kernel_neon_end()



#endif /* ! __ASM_FPU_H */