34 lines
1.0 KiB
C
34 lines
1.0 KiB
C
|
/* SPDX-License-Identifier: GPL-2.0-only */
|
||
|
/*
|
||
|
* linux/arch/arm/include/asm/neon.h
|
||
|
*
|
||
|
* Copyright (C) 2013 Linaro Ltd <ard.biesheuvel@linaro.org>
|
||
|
*/
|
||
|
|
||
|
#include <asm/hwcap.h>
|
||
|
|
||
|
#define cpu_has_neon() (!!(elf_hwcap & HWCAP_NEON))
|
||
|
|
||
|
#ifdef __ARM_NEON__
|
||
|
|
||
|
/*
|
||
|
* If you are affected by the BUILD_BUG below, it probably means that you are
|
||
|
* using NEON code /and/ calling the kernel_neon_begin() function from the same
|
||
|
* compilation unit. To prevent issues that may arise from GCC reordering or
|
||
|
* generating(1) NEON instructions outside of these begin/end functions, the
|
||
|
* only supported way of using NEON code in the kernel is by isolating it in a
|
||
|
* separate compilation unit, and calling it from another unit from inside a
|
||
|
* kernel_neon_begin/kernel_neon_end pair.
|
||
|
*
|
||
|
* (1) Current GCC (4.7) might generate NEON instructions at O3 level if
|
||
|
* -mpfu=neon is set.
|
||
|
*/
|
||
|
|
||
|
#define kernel_neon_begin() \
|
||
|
BUILD_BUG_ON_MSG(1, "kernel_neon_begin() called from NEON code")
|
||
|
|
||
|
#else
|
||
|
void kernel_neon_begin(void);
|
||
|
#endif
|
||
|
void kernel_neon_end(void);
|