2 * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
9 #ifndef __ASM_CPUFEATURE_H
10 #define __ASM_CPUFEATURE_H
12 #include <asm/hwcap.h>
15 * In the arm64 world (as in the ARM world), elf_hwcap is used both internally
16 * in the kernel and for user space to keep track of which optional features
17 * are supported by the current system. So let's map feature 'x' to HWCAP_x.
18 * Note that HWCAP_x constants are bit fields so we need to take the log.
21 #define MAX_CPU_FEATURES (8 * sizeof(elf_hwcap))
22 #define cpu_feature(x) ilog2(HWCAP_ ## x)
24 static inline bool cpu_have_feature(unsigned int num
)
26 return elf_hwcap
& (1UL << num
);