[linux-2.6-block.git] / arch / arm64 / include / asm / cpufeature.h

/*
 * 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_WORKAROUND_845719			2
#define ARM64_HAS_SYSREG_GIC_CPUIF		3
#define ARM64_HAS_PAN				4
#define ARM64_HAS_LSE_ATOMICS			5
#define ARM64_WORKAROUND_CAVIUM_23154		6

#define ARM64_NCAPS				7

#ifndef __ASSEMBLY__

#include <linux/kernel.h>

struct arm64_cpu_capabilities {
	const char *desc;
	u16 capability;
	bool (*matches)(const struct arm64_cpu_capabilities *);
	void (*enable)(void);
	union {
		struct {	/* To be used for erratum handling only */
			u32 midr_model;
			u32 midr_range_min, midr_range_max;
		};

		struct {	/* Feature register checking */
			int field_pos;
			int min_field_value;
		};
	};
};

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);
}

static inline int __attribute_const__ cpuid_feature_extract_field(u64 features,
								  int field)
{
	return (s64)(features << (64 - 4 - field)) >> (64 - 4);
}


void check_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
			    const char *info);
void check_local_cpu_errata(void);
void check_local_cpu_features(void);
bool cpu_supports_mixed_endian_el0(void);
bool system_supports_mixed_endian_el0(void);

#endif /* __ASSEMBLY__ */

#endif
Commit	Line	Data
3be1a5c4 AB	1	/*
	2	* Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
	3	*
	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.
	7	*/
	8
	9	#ifndef __ASM_CPUFEATURE_H
	10	#define __ASM_CPUFEATURE_H
	11
	12	#include <asm/hwcap.h>
	13
	14	/*
	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.
	19	*/
	20
	21	#define MAX_CPU_FEATURES (8 * sizeof(elf_hwcap))
	22	#define cpu_feature(x) ilog2(HWCAP_ ## x)
	23
5afaa1fc AP	24	#define ARM64_WORKAROUND_CLEAN_CACHE 0
5afaa1fc AP	25	#define ARM64_WORKAROUND_DEVICE_LOAD_ACQUIRE 1
905e8c5d	26	#define ARM64_WORKAROUND_845719 2
94a9e04a	27	#define ARM64_HAS_SYSREG_GIC_CPUIF 3
338d4f49	28	#define ARM64_HAS_PAN 4
c739dc83	29	#define ARM64_HAS_LSE_ATOMICS 5
6d4e11c5	30	#define ARM64_WORKAROUND_CAVIUM_23154 6
301bcfac	31
6d4e11c5	32	#define ARM64_NCAPS 7
301bcfac AP	33
301bcfac AP	34	#ifndef __ASSEMBLY__
930da09f	35
144e9697 WD	36	#include <linux/kernel.h>
144e9697 WD	37
359b7064 MZ	38	struct arm64_cpu_capabilities {
	39	const char *desc;
	40	u16 capability;
	41	bool (matches)(const struct arm64_cpu_capabilities );
1c076303	42	void (*enable)(void);
359b7064 MZ	43	union {
	44	struct { /* To be used for erratum handling only */
	45	u32 midr_model;
	46	u32 midr_range_min, midr_range_max;
	47	};
94a9e04a MZ	48
94a9e04a MZ	49	struct { /* Feature register checking */
18ffa046 JM	50	int field_pos;
18ffa046 JM	51	int min_field_value;
94a9e04a	52	};
359b7064 MZ	53	};
	54	};
	55
06f9eb88	56	extern DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
930da09f	57
3be1a5c4 AB	58	static inline bool cpu_have_feature(unsigned int num)
	59	{
	60	return elf_hwcap & (1UL << num);
	61	}
	62
930da09f AP	63	static inline bool cpus_have_cap(unsigned int num)
930da09f AP	64	{
06f9eb88	65	if (num >= ARM64_NCAPS)
930da09f AP	66	return false;
	67	return test_bit(num, cpu_hwcaps);
	68	}
	69
	70	static inline void cpus_set_cap(unsigned int num)
	71	{
06f9eb88	72	if (num >= ARM64_NCAPS)
930da09f	73	pr_warn("Attempt to set an illegal CPU capability (%d >= %d)\n",
06f9eb88	74	num, ARM64_NCAPS);
930da09f AP	75	else
	76	__set_bit(num, cpu_hwcaps);
	77	}
	78
79b0e09a JM	79	static inline int __attribute_const__ cpuid_feature_extract_field(u64 features,
	80	int field)
	81	{
	82	return (s64)(features << (64 - 4 - field)) >> (64 - 4);
	83	}
	84
	85
359b7064 MZ	86	void check_cpu_capabilities(const struct arm64_cpu_capabilities *caps,
359b7064 MZ	87	const char *info);
e116a375	88	void check_local_cpu_errata(void);
359b7064	89	void check_local_cpu_features(void);
04597a65 SP	90	bool cpu_supports_mixed_endian_el0(void);
04597a65 SP	91	bool system_supports_mixed_endian_el0(void);
e116a375	92
301bcfac AP	93	#endif /* __ASSEMBLY__ */
301bcfac AP	94
3be1a5c4	95	#endif