From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: André Fabian Silva Delgado Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- arch/arm64/include/asm/cpufeature.h | 76 +++++++++++++++++++++++++++++++++++++ 1 file changed, 76 insertions(+) create mode 100644 arch/arm64/include/asm/cpufeature.h (limited to 'arch/arm64/include/asm/cpufeature.h') diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h new file mode 100644 index 000000000..82cb9f98b --- /dev/null +++ b/arch/arm64/include/asm/cpufeature.h @@ -0,0 +1,76 @@ +/* + * Copyright (C) 2014 Linaro Ltd. + * + * 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 + +/* + * 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_NCAPS 3 + +#ifndef __ASSEMBLY__ + +struct arm64_cpu_capabilities { + const char *desc; + u16 capability; + bool (*matches)(const struct arm64_cpu_capabilities *); + union { + struct { /* To be used for erratum handling only */ + u32 midr_model; + u32 midr_range_min, midr_range_max; + }; + }; +}; + +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_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 -- cgit v1.2.3-54-g00ecf