Commit cb2b7b7d authored Mar 29, 2024 by Samuel Holland Committed by Andrew Morton May 19, 2024

ARM: implement ARCH_HAS_KERNEL_FPU_SUPPORT

ARM 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.

[samuel.holland@sifive.com: ARM: do not select ARCH_HAS_KERNEL_FPU_SUPPORT]
  Link: https://lkml.kernel.org/r/20240509013727.648600-1-samuel.holland@sifive.com
Link: https://lkml.kernel.org/r/20240329072441.591471-3-samuel.holland@sifive.com


Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
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: 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>
Cc: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

parent 6cbd1d6d

arch/arm/Makefile

+7 −0

Original line number	Diff line number	Diff line
		@@ -130,6 +130,13 @@ endif
		# Accept old syntax despite ".syntax unified"
		AFLAGS_NOWARN :=$(call as-option,-Wa$(comma)-mno-warn-deprecated,-Wa$(comma)-W)

		# 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_FPU += -march=armv7-a -mfloat-abi=softfp -mfpu=neon

		ifeq ($(CONFIG_THUMB2_KERNEL),y)
		CFLAGS_ISA :=-Wa,-mimplicit-it=always $(AFLAGS_NOWARN)
		AFLAGS_ISA :=$(CFLAGS_ISA) -Wa$(comma)-mthumb

arch/arm/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 */