summaryrefslogtreecommitdiffstats
path: root/arch/arm64/include/asm/cpufeature.h
blob: 07547ccc1f2bd2945edd53a037915c0368ab2400 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
/*
 * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 */

#ifndef __ASM_CPUFEATURE_H
#define __ASM_CPUFEATURE_H

#include <asm/hwcap.h>

/*
 * In the arm64 world (as in the ARM world), elf_hwcap is used both internally
 * in the kernel and for user space to keep track of which optional features
 * are supported by the current system. So let's map feature 'x' to HWCAP_x.
 * Note that HWCAP_x constants are bit fields so we need to take the log.
 */

#define MAX_CPU_FEATURES	(8 * sizeof(elf_hwcap))
#define cpu_feature(x)		ilog2(HWCAP_ ## x)

#define ARM64_WORKAROUND_CLEAN_CACHE		0
#define ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE	1

#define ARM64_NCAPS				2

#ifndef __ASSEMBLY__

extern DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);

static inline bool cpu_have_feature(unsigned int num)
{
	return elf_hwcap & (1UL << num);
}

static inline bool cpus_have_cap(unsigned int num)
{
	if (num >= ARM64_NCAPS)
		return false;
	return test_bit(num, cpu_hwcaps);
}

static inline void cpus_set_cap(unsigned int num)
{
	if (num >= ARM64_NCAPS)
		pr_warn("Attempt to set an illegal CPU capability (%d >= %d)\n",
			num, ARM64_NCAPS);
	else
		__set_bit(num, cpu_hwcaps);
}

void check_local_cpu_errata(void);

#endif /* __ASSEMBLY__ */

#endif