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diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
+ */
+
+#ifndef __ASM_CPUFEATURE_H
+#define __ASM_CPUFEATURE_H
+
+#include <asm/alternative-macros.h>
+#include <asm/cpucaps.h>
+#include <asm/cputype.h>
+#include <asm/hwcap.h>
+#include <asm/sysreg.h>
+
+#define MAX_CPU_FEATURES 128
+#define cpu_feature(x) KERNEL_HWCAP_ ## x
+
+#ifndef __ASSEMBLY__
+
+#include <linux/bug.h>
+#include <linux/jump_label.h>
+#include <linux/kernel.h>
+
+/*
+ * CPU feature register tracking
+ *
+ * The safe value of a CPUID feature field is dependent on the implications
+ * of the values assigned to it by the architecture. Based on the relationship
+ * between the values, the features are classified into 3 types - LOWER_SAFE,
+ * HIGHER_SAFE and EXACT.
+ *
+ * The lowest value of all the CPUs is chosen for LOWER_SAFE and highest
+ * for HIGHER_SAFE. It is expected that all CPUs have the same value for
+ * a field when EXACT is specified, failing which, the safe value specified
+ * in the table is chosen.
+ */
+
+enum ftr_type {
+ FTR_EXACT, /* Use a predefined safe value */
+ FTR_LOWER_SAFE, /* Smaller value is safe */
+ FTR_HIGHER_SAFE, /* Bigger value is safe */
+ FTR_HIGHER_OR_ZERO_SAFE, /* Bigger value is safe, but 0 is biggest */
+};
+
+#define FTR_STRICT true /* SANITY check strict matching required */
+#define FTR_NONSTRICT false /* SANITY check ignored */
+
+#define FTR_SIGNED true /* Value should be treated as signed */
+#define FTR_UNSIGNED false /* Value should be treated as unsigned */
+
+#define FTR_VISIBLE true /* Feature visible to the user space */
+#define FTR_HIDDEN false /* Feature is hidden from the user */
+
+#define FTR_VISIBLE_IF_IS_ENABLED(config) \
+ (IS_ENABLED(config) ? FTR_VISIBLE : FTR_HIDDEN)
+
+struct arm64_ftr_bits {
+ bool sign; /* Value is signed ? */
+ bool visible;
+ bool strict; /* CPU Sanity check: strict matching required ? */
+ enum ftr_type type;
+ u8 shift;
+ u8 width;
+ s64 safe_val; /* safe value for FTR_EXACT features */
+};
+
+/*
+ * Describe the early feature override to the core override code:
+ *
+ * @val Values that are to be merged into the final
+ * sanitised value of the register. Only the bitfields
+ * set to 1 in @mask are valid
+ * @mask Mask of the features that are overridden by @val
+ *
+ * A @mask field set to full-1 indicates that the corresponding field
+ * in @val is a valid override.
+ *
+ * A @mask field set to full-0 with the corresponding @val field set
+ * to full-0 denotes that this field has no override
+ *
+ * A @mask field set to full-0 with the corresponding @val field set
+ * to full-1 denotes thath this field has an invalid override.
+ */
+struct arm64_ftr_override {
+ u64 val;
+ u64 mask;
+};
+
+/*
+ * @arm64_ftr_reg - Feature register
+ * @strict_mask Bits which should match across all CPUs for sanity.
+ * @sys_val Safe value across the CPUs (system view)
+ */
+struct arm64_ftr_reg {
+ const char *name;
+ u64 strict_mask;
+ u64 user_mask;
+ u64 sys_val;
+ u64 user_val;
+ struct arm64_ftr_override *override;
+ const struct arm64_ftr_bits *ftr_bits;
+};
+
+extern struct arm64_ftr_reg arm64_ftr_reg_ctrel0;
+
+/*
+ * CPU capabilities:
+ *
+ * We use arm64_cpu_capabilities to represent system features, errata work
+ * arounds (both used internally by kernel and tracked in cpu_hwcaps) and
+ * ELF HWCAPs (which are exposed to user).
+ *
+ * To support systems with heterogeneous CPUs, we need to make sure that we
+ * detect the capabilities correctly on the system and take appropriate
+ * measures to ensure there are no incompatibilities.
+ *
+ * This comment tries to explain how we treat the capabilities.
+ * Each capability has the following list of attributes :
+ *
+ * 1) Scope of Detection : The system detects a given capability by
+ * performing some checks at runtime. This could be, e.g, checking the
+ * value of a field in CPU ID feature register or checking the cpu
+ * model. The capability provides a call back ( @matches() ) to
+ * perform the check. Scope defines how the checks should be performed.
+ * There are three cases:
+ *
+ * a) SCOPE_LOCAL_CPU: check all the CPUs and "detect" if at least one
+ * matches. This implies, we have to run the check on all the
+ * booting CPUs, until the system decides that state of the
+ * capability is finalised. (See section 2 below)
+ * Or
+ * b) SCOPE_SYSTEM: check all the CPUs and "detect" if all the CPUs
+ * matches. This implies, we run the check only once, when the
+ * system decides to finalise the state of the capability. If the
+ * capability relies on a field in one of the CPU ID feature
+ * registers, we use the sanitised value of the register from the
+ * CPU feature infrastructure to make the decision.
+ * Or
+ * c) SCOPE_BOOT_CPU: Check only on the primary boot CPU to detect the
+ * feature. This category is for features that are "finalised"
+ * (or used) by the kernel very early even before the SMP cpus
+ * are brought up.
+ *
+ * The process of detection is usually denoted by "update" capability
+ * state in the code.
+ *
+ * 2) Finalise the state : The kernel should finalise the state of a
+ * capability at some point during its execution and take necessary
+ * actions if any. Usually, this is done, after all the boot-time
+ * enabled CPUs are brought up by the kernel, so that it can make
+ * better decision based on the available set of CPUs. However, there
+ * are some special cases, where the action is taken during the early
+ * boot by the primary boot CPU. (e.g, running the kernel at EL2 with
+ * Virtualisation Host Extensions). The kernel usually disallows any
+ * changes to the state of a capability once it finalises the capability
+ * and takes any action, as it may be impossible to execute the actions
+ * safely. A CPU brought up after a capability is "finalised" is
+ * referred to as "Late CPU" w.r.t the capability. e.g, all secondary
+ * CPUs are treated "late CPUs" for capabilities determined by the boot
+ * CPU.
+ *
+ * At the moment there are two passes of finalising the capabilities.
+ * a) Boot CPU scope capabilities - Finalised by primary boot CPU via
+ * setup_boot_cpu_capabilities().
+ * b) Everything except (a) - Run via setup_system_capabilities().
+ *
+ * 3) Verification: When a CPU is brought online (e.g, by user or by the
+ * kernel), the kernel should make sure that it is safe to use the CPU,
+ * by verifying that the CPU is compliant with the state of the
+ * capabilities finalised already. This happens via :
+ *
+ * secondary_start_kernel()-> check_local_cpu_capabilities()
+ *
+ * As explained in (2) above, capabilities could be finalised at
+ * different points in the execution. Each newly booted CPU is verified
+ * against the capabilities that have been finalised by the time it
+ * boots.
+ *
+ * a) SCOPE_BOOT_CPU : All CPUs are verified against the capability
+ * except for the primary boot CPU.
+ *
+ * b) SCOPE_LOCAL_CPU, SCOPE_SYSTEM: All CPUs hotplugged on by the
+ * user after the kernel boot are verified against the capability.
+ *
+ * If there is a conflict, the kernel takes an action, based on the
+ * severity (e.g, a CPU could be prevented from booting or cause a
+ * kernel panic). The CPU is allowed to "affect" the state of the
+ * capability, if it has not been finalised already. See section 5
+ * for more details on conflicts.
+ *
+ * 4) Action: As mentioned in (2), the kernel can take an action for each
+ * detected capability, on all CPUs on the system. Appropriate actions
+ * include, turning on an architectural feature, modifying the control
+ * registers (e.g, SCTLR, TCR etc.) or patching the kernel via
+ * alternatives. The kernel patching is batched and performed at later
+ * point. The actions are always initiated only after the capability
+ * is finalised. This is usally denoted by "enabling" the capability.
+ * The actions are initiated as follows :
+ * a) Action is triggered on all online CPUs, after the capability is
+ * finalised, invoked within the stop_machine() context from
+ * enable_cpu_capabilitie().
+ *
+ * b) Any late CPU, brought up after (1), the action is triggered via:
+ *
+ * check_local_cpu_capabilities() -> verify_local_cpu_capabilities()
+ *
+ * 5) Conflicts: Based on the state of the capability on a late CPU vs.
+ * the system state, we could have the following combinations :
+ *
+ * x-----------------------------x
+ * | Type | System | Late CPU |
+ * |-----------------------------|
+ * | a | y | n |
+ * |-----------------------------|
+ * | b | n | y |
+ * x-----------------------------x
+ *
+ * Two separate flag bits are defined to indicate whether each kind of
+ * conflict can be allowed:
+ * ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU - Case(a) is allowed
+ * ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU - Case(b) is allowed
+ *
+ * Case (a) is not permitted for a capability that the system requires
+ * all CPUs to have in order for the capability to be enabled. This is
+ * typical for capabilities that represent enhanced functionality.
+ *
+ * Case (b) is not permitted for a capability that must be enabled
+ * during boot if any CPU in the system requires it in order to run
+ * safely. This is typical for erratum work arounds that cannot be
+ * enabled after the corresponding capability is finalised.
+ *
+ * In some non-typical cases either both (a) and (b), or neither,
+ * should be permitted. This can be described by including neither
+ * or both flags in the capability's type field.
+ *
+ * In case of a conflict, the CPU is prevented from booting. If the
+ * ARM64_CPUCAP_PANIC_ON_CONFLICT flag is specified for the capability,
+ * then a kernel panic is triggered.
+ */
+
+
+/*
+ * Decide how the capability is detected.
+ * On any local CPU vs System wide vs the primary boot CPU
+ */
+#define ARM64_CPUCAP_SCOPE_LOCAL_CPU ((u16)BIT(0))
+#define ARM64_CPUCAP_SCOPE_SYSTEM ((u16)BIT(1))
+/*
+ * The capabilitiy is detected on the Boot CPU and is used by kernel
+ * during early boot. i.e, the capability should be "detected" and
+ * "enabled" as early as possibly on all booting CPUs.
+ */
+#define ARM64_CPUCAP_SCOPE_BOOT_CPU ((u16)BIT(2))
+#define ARM64_CPUCAP_SCOPE_MASK \
+ (ARM64_CPUCAP_SCOPE_SYSTEM | \
+ ARM64_CPUCAP_SCOPE_LOCAL_CPU | \
+ ARM64_CPUCAP_SCOPE_BOOT_CPU)
+
+#define SCOPE_SYSTEM ARM64_CPUCAP_SCOPE_SYSTEM
+#define SCOPE_LOCAL_CPU ARM64_CPUCAP_SCOPE_LOCAL_CPU
+#define SCOPE_BOOT_CPU ARM64_CPUCAP_SCOPE_BOOT_CPU
+#define SCOPE_ALL ARM64_CPUCAP_SCOPE_MASK
+
+/*
+ * Is it permitted for a late CPU to have this capability when system
+ * hasn't already enabled it ?
+ */
+#define ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU ((u16)BIT(4))
+/* Is it safe for a late CPU to miss this capability when system has it */
+#define ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU ((u16)BIT(5))
+/* Panic when a conflict is detected */
+#define ARM64_CPUCAP_PANIC_ON_CONFLICT ((u16)BIT(6))
+
+/*
+ * CPU errata workarounds that need to be enabled at boot time if one or
+ * more CPUs in the system requires it. When one of these capabilities
+ * has been enabled, it is safe to allow any CPU to boot that doesn't
+ * require the workaround. However, it is not safe if a "late" CPU
+ * requires a workaround and the system hasn't enabled it already.
+ */
+#define ARM64_CPUCAP_LOCAL_CPU_ERRATUM \
+ (ARM64_CPUCAP_SCOPE_LOCAL_CPU | ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU)
+/*
+ * CPU feature detected at boot time based on system-wide value of a
+ * feature. It is safe for a late CPU to have this feature even though
+ * the system hasn't enabled it, although the feature will not be used
+ * by Linux in this case. If the system has enabled this feature already,
+ * then every late CPU must have it.
+ */
+#define ARM64_CPUCAP_SYSTEM_FEATURE \
+ (ARM64_CPUCAP_SCOPE_SYSTEM | ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU)
+/*
+ * CPU feature detected at boot time based on feature of one or more CPUs.
+ * All possible conflicts for a late CPU are ignored.
+ * NOTE: this means that a late CPU with the feature will *not* cause the
+ * capability to be advertised by cpus_have_*cap()!
+ */
+#define ARM64_CPUCAP_WEAK_LOCAL_CPU_FEATURE \
+ (ARM64_CPUCAP_SCOPE_LOCAL_CPU | \
+ ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU | \
+ ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU)
+
+/*
+ * CPU feature detected at boot time, on one or more CPUs. A late CPU
+ * is not allowed to have the capability when the system doesn't have it.
+ * It is Ok for a late CPU to miss the feature.
+ */
+#define ARM64_CPUCAP_BOOT_RESTRICTED_CPU_LOCAL_FEATURE \
+ (ARM64_CPUCAP_SCOPE_LOCAL_CPU | \
+ ARM64_CPUCAP_OPTIONAL_FOR_LATE_CPU)
+
+/*
+ * CPU feature used early in the boot based on the boot CPU. All secondary
+ * CPUs must match the state of the capability as detected by the boot CPU. In
+ * case of a conflict, a kernel panic is triggered.
+ */
+#define ARM64_CPUCAP_STRICT_BOOT_CPU_FEATURE \
+ (ARM64_CPUCAP_SCOPE_BOOT_CPU | ARM64_CPUCAP_PANIC_ON_CONFLICT)
+
+/*
+ * CPU feature used early in the boot based on the boot CPU. It is safe for a
+ * late CPU to have this feature even though the boot CPU hasn't enabled it,
+ * although the feature will not be used by Linux in this case. If the boot CPU
+ * has enabled this feature already, then every late CPU must have it.
+ */
+#define ARM64_CPUCAP_BOOT_CPU_FEATURE \
+ (ARM64_CPUCAP_SCOPE_BOOT_CPU | ARM64_CPUCAP_PERMITTED_FOR_LATE_CPU)
+
+struct arm64_cpu_capabilities {
+ const char *desc;
+ u16 capability;
+ u16 type;
+ bool (*matches)(const struct arm64_cpu_capabilities *caps, int scope);
+ /*
+ * Take the appropriate actions to configure this capability
+ * for this CPU. If the capability is detected by the kernel
+ * this will be called on all the CPUs in the system,
+ * including the hotplugged CPUs, regardless of whether the
+ * capability is available on that specific CPU. This is
+ * useful for some capabilities (e.g, working around CPU
+ * errata), where all the CPUs must take some action (e.g,
+ * changing system control/configuration). Thus, if an action
+ * is required only if the CPU has the capability, then the
+ * routine must check it before taking any action.
+ */
+ void (*cpu_enable)(const struct arm64_cpu_capabilities *cap);
+ union {
+ struct { /* To be used for erratum handling only */
+ struct midr_range midr_range;
+ const struct arm64_midr_revidr {
+ u32 midr_rv; /* revision/variant */
+ u32 revidr_mask;
+ } * const fixed_revs;
+ };
+
+ const struct midr_range *midr_range_list;
+ struct { /* Feature register checking */
+ u32 sys_reg;
+ u8 field_pos;
+ u8 field_width;
+ u8 min_field_value;
+ u8 hwcap_type;
+ bool sign;
+ unsigned long hwcap;
+ };
+ };
+
+ /*
+ * An optional list of "matches/cpu_enable" pair for the same
+ * "capability" of the same "type" as described by the parent.
+ * Only matches(), cpu_enable() and fields relevant to these
+ * methods are significant in the list. The cpu_enable is
+ * invoked only if the corresponding entry "matches()".
+ * However, if a cpu_enable() method is associated
+ * with multiple matches(), care should be taken that either
+ * the match criteria are mutually exclusive, or that the
+ * method is robust against being called multiple times.
+ */
+ const struct arm64_cpu_capabilities *match_list;
+};
+
+static inline int cpucap_default_scope(const struct arm64_cpu_capabilities *cap)
+{
+ return cap->type & ARM64_CPUCAP_SCOPE_MASK;
+}
+
+/*
+ * Generic helper for handling capabilities with multiple (match,enable) pairs
+ * of call backs, sharing the same capability bit.
+ * Iterate over each entry to see if at least one matches.
+ */
+static inline bool
+cpucap_multi_entry_cap_matches(const struct arm64_cpu_capabilities *entry,
+ int scope)
+{
+ const struct arm64_cpu_capabilities *caps;
+
+ for (caps = entry->match_list; caps->matches; caps++)
+ if (caps->matches(caps, scope))
+ return true;
+
+ return false;
+}
+
+static __always_inline bool is_vhe_hyp_code(void)
+{
+ /* Only defined for code run in VHE hyp context */
+ return __is_defined(__KVM_VHE_HYPERVISOR__);
+}
+
+static __always_inline bool is_nvhe_hyp_code(void)
+{
+ /* Only defined for code run in NVHE hyp context */
+ return __is_defined(__KVM_NVHE_HYPERVISOR__);
+}
+
+static __always_inline bool is_hyp_code(void)
+{
+ return is_vhe_hyp_code() || is_nvhe_hyp_code();
+}
+
+extern DECLARE_BITMAP(cpu_hwcaps, ARM64_NCAPS);
+
+extern DECLARE_BITMAP(boot_capabilities, ARM64_NCAPS);
+
+#define for_each_available_cap(cap) \
+ for_each_set_bit(cap, cpu_hwcaps, ARM64_NCAPS)
+
+bool this_cpu_has_cap(unsigned int cap);
+void cpu_set_feature(unsigned int num);
+bool cpu_have_feature(unsigned int num);
+unsigned long cpu_get_elf_hwcap(void);
+unsigned long cpu_get_elf_hwcap2(void);
+
+#define cpu_set_named_feature(name) cpu_set_feature(cpu_feature(name))
+#define cpu_have_named_feature(name) cpu_have_feature(cpu_feature(name))
+
+static __always_inline bool system_capabilities_finalized(void)
+{
+ return alternative_has_feature_likely(ARM64_ALWAYS_SYSTEM);
+}
+
+/*
+ * Test for a capability with a runtime check.
+ *
+ * Before the capability is detected, this returns false.
+ */
+static __always_inline bool cpus_have_cap(unsigned int num)
+{
+ if (num >= ARM64_NCAPS)
+ return false;
+ return arch_test_bit(num, cpu_hwcaps);
+}
+
+/*
+ * Test for a capability without a runtime check.
+ *
+ * Before capabilities are finalized, this returns false.
+ * After capabilities are finalized, this is patched to avoid a runtime check.
+ *
+ * @num must be a compile-time constant.
+ */
+static __always_inline bool __cpus_have_const_cap(int num)
+{
+ if (num >= ARM64_NCAPS)
+ return false;
+ return alternative_has_feature_unlikely(num);
+}
+
+/*
+ * Test for a capability without a runtime check.
+ *
+ * Before capabilities are finalized, this will BUG().
+ * After capabilities are finalized, this is patched to avoid a runtime check.
+ *
+ * @num must be a compile-time constant.
+ */
+static __always_inline bool cpus_have_final_cap(int num)
+{
+ if (system_capabilities_finalized())
+ return __cpus_have_const_cap(num);
+ else
+ BUG();
+}
+
+/*
+ * Test for a capability, possibly with a runtime check for non-hyp code.
+ *
+ * For hyp code, this behaves the same as cpus_have_final_cap().
+ *
+ * For non-hyp code:
+ * Before capabilities are finalized, this behaves as cpus_have_cap().
+ * After capabilities are finalized, this is patched to avoid a runtime check.
+ *
+ * @num must be a compile-time constant.
+ */
+static __always_inline bool cpus_have_const_cap(int num)
+{
+ if (is_hyp_code())
+ return cpus_have_final_cap(num);
+ else if (system_capabilities_finalized())
+ return __cpus_have_const_cap(num);
+ else
+ return cpus_have_cap(num);
+}
+
+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_signed_field_width(u64 features, int field, int width)
+{
+ return (s64)(features << (64 - width - field)) >> (64 - width);
+}
+
+static inline int __attribute_const__
+cpuid_feature_extract_signed_field(u64 features, int field)
+{
+ return cpuid_feature_extract_signed_field_width(features, field, 4);
+}
+
+static __always_inline unsigned int __attribute_const__
+cpuid_feature_extract_unsigned_field_width(u64 features, int field, int width)
+{
+ return (u64)(features << (64 - width - field)) >> (64 - width);
+}
+
+static __always_inline unsigned int __attribute_const__
+cpuid_feature_extract_unsigned_field(u64 features, int field)
+{
+ return cpuid_feature_extract_unsigned_field_width(features, field, 4);
+}
+
+/*
+ * Fields that identify the version of the Performance Monitors Extension do
+ * not follow the standard ID scheme. See ARM DDI 0487E.a page D13-2825,
+ * "Alternative ID scheme used for the Performance Monitors Extension version".
+ */
+static inline u64 __attribute_const__
+cpuid_feature_cap_perfmon_field(u64 features, int field, u64 cap)
+{
+ u64 val = cpuid_feature_extract_unsigned_field(features, field);
+ u64 mask = GENMASK_ULL(field + 3, field);
+
+ /* Treat IMPLEMENTATION DEFINED functionality as unimplemented */
+ if (val == ID_AA64DFR0_EL1_PMUVer_IMP_DEF)
+ val = 0;
+
+ if (val > cap) {
+ features &= ~mask;
+ features |= (cap << field) & mask;
+ }
+
+ return features;
+}
+
+static inline u64 arm64_ftr_mask(const struct arm64_ftr_bits *ftrp)
+{
+ return (u64)GENMASK(ftrp->shift + ftrp->width - 1, ftrp->shift);
+}
+
+static inline u64 arm64_ftr_reg_user_value(const struct arm64_ftr_reg *reg)
+{
+ return (reg->user_val | (reg->sys_val & reg->user_mask));
+}
+
+static inline int __attribute_const__
+cpuid_feature_extract_field_width(u64 features, int field, int width, bool sign)
+{
+ if (WARN_ON_ONCE(!width))
+ width = 4;
+ return (sign) ?
+ cpuid_feature_extract_signed_field_width(features, field, width) :
+ cpuid_feature_extract_unsigned_field_width(features, field, width);
+}
+
+static inline int __attribute_const__
+cpuid_feature_extract_field(u64 features, int field, bool sign)
+{
+ return cpuid_feature_extract_field_width(features, field, 4, sign);
+}
+
+static inline s64 arm64_ftr_value(const struct arm64_ftr_bits *ftrp, u64 val)
+{
+ return (s64)cpuid_feature_extract_field_width(val, ftrp->shift, ftrp->width, ftrp->sign);
+}
+
+static inline bool id_aa64mmfr0_mixed_endian_el0(u64 mmfr0)
+{
+ return cpuid_feature_extract_unsigned_field(mmfr0, ID_AA64MMFR0_EL1_BIGEND_SHIFT) == 0x1 ||
+ cpuid_feature_extract_unsigned_field(mmfr0, ID_AA64MMFR0_EL1_BIGENDEL0_SHIFT) == 0x1;
+}
+
+static inline bool id_aa64pfr0_32bit_el1(u64 pfr0)
+{
+ u32 val = cpuid_feature_extract_unsigned_field(pfr0, ID_AA64PFR0_EL1_EL1_SHIFT);
+
+ return val == ID_AA64PFR0_EL1_ELx_32BIT_64BIT;
+}
+
+static inline bool id_aa64pfr0_32bit_el0(u64 pfr0)
+{
+ u32 val = cpuid_feature_extract_unsigned_field(pfr0, ID_AA64PFR0_EL1_EL0_SHIFT);
+
+ return val == ID_AA64PFR0_EL1_ELx_32BIT_64BIT;
+}
+
+static inline bool id_aa64pfr0_sve(u64 pfr0)
+{
+ u32 val = cpuid_feature_extract_unsigned_field(pfr0, ID_AA64PFR0_EL1_SVE_SHIFT);
+
+ return val > 0;
+}
+
+static inline bool id_aa64pfr1_sme(u64 pfr1)
+{
+ u32 val = cpuid_feature_extract_unsigned_field(pfr1, ID_AA64PFR1_EL1_SME_SHIFT);
+
+ return val > 0;
+}
+
+static inline bool id_aa64pfr1_mte(u64 pfr1)
+{
+ u32 val = cpuid_feature_extract_unsigned_field(pfr1, ID_AA64PFR1_EL1_MTE_SHIFT);
+
+ return val >= ID_AA64PFR1_EL1_MTE_MTE2;
+}
+
+void __init setup_cpu_features(void);
+void check_local_cpu_capabilities(void);
+
+u64 read_sanitised_ftr_reg(u32 id);
+u64 __read_sysreg_by_encoding(u32 sys_id);
+
+static inline bool cpu_supports_mixed_endian_el0(void)
+{
+ return id_aa64mmfr0_mixed_endian_el0(read_cpuid(ID_AA64MMFR0_EL1));
+}
+
+
+static inline bool supports_csv2p3(int scope)
+{
+ u64 pfr0;
+ u8 csv2_val;
+
+ if (scope == SCOPE_LOCAL_CPU)
+ pfr0 = read_sysreg_s(SYS_ID_AA64PFR0_EL1);
+ else
+ pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
+
+ csv2_val = cpuid_feature_extract_unsigned_field(pfr0,
+ ID_AA64PFR0_EL1_CSV2_SHIFT);
+ return csv2_val == 3;
+}
+
+static inline bool supports_clearbhb(int scope)
+{
+ u64 isar2;
+
+ if (scope == SCOPE_LOCAL_CPU)
+ isar2 = read_sysreg_s(SYS_ID_AA64ISAR2_EL1);
+ else
+ isar2 = read_sanitised_ftr_reg(SYS_ID_AA64ISAR2_EL1);
+
+ return cpuid_feature_extract_unsigned_field(isar2,
+ ID_AA64ISAR2_EL1_CLRBHB_SHIFT);
+}
+
+const struct cpumask *system_32bit_el0_cpumask(void);
+DECLARE_STATIC_KEY_FALSE(arm64_mismatched_32bit_el0);
+
+static inline bool system_supports_32bit_el0(void)
+{
+ u64 pfr0 = read_sanitised_ftr_reg(SYS_ID_AA64PFR0_EL1);
+
+ return static_branch_unlikely(&arm64_mismatched_32bit_el0) ||
+ id_aa64pfr0_32bit_el0(pfr0);
+}
+
+static inline bool system_supports_4kb_granule(void)
+{
+ u64 mmfr0;
+ u32 val;
+
+ mmfr0 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
+ val = cpuid_feature_extract_unsigned_field(mmfr0,
+ ID_AA64MMFR0_EL1_TGRAN4_SHIFT);
+
+ return (val >= ID_AA64MMFR0_EL1_TGRAN4_SUPPORTED_MIN) &&
+ (val <= ID_AA64MMFR0_EL1_TGRAN4_SUPPORTED_MAX);
+}
+
+static inline bool system_supports_64kb_granule(void)
+{
+ u64 mmfr0;
+ u32 val;
+
+ mmfr0 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
+ val = cpuid_feature_extract_unsigned_field(mmfr0,
+ ID_AA64MMFR0_EL1_TGRAN64_SHIFT);
+
+ return (val >= ID_AA64MMFR0_EL1_TGRAN64_SUPPORTED_MIN) &&
+ (val <= ID_AA64MMFR0_EL1_TGRAN64_SUPPORTED_MAX);
+}
+
+static inline bool system_supports_16kb_granule(void)
+{
+ u64 mmfr0;
+ u32 val;
+
+ mmfr0 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
+ val = cpuid_feature_extract_unsigned_field(mmfr0,
+ ID_AA64MMFR0_EL1_TGRAN16_SHIFT);
+
+ return (val >= ID_AA64MMFR0_EL1_TGRAN16_SUPPORTED_MIN) &&
+ (val <= ID_AA64MMFR0_EL1_TGRAN16_SUPPORTED_MAX);
+}
+
+static inline bool system_supports_mixed_endian_el0(void)
+{
+ return id_aa64mmfr0_mixed_endian_el0(read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1));
+}
+
+static inline bool system_supports_mixed_endian(void)
+{
+ u64 mmfr0;
+ u32 val;
+
+ mmfr0 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1);
+ val = cpuid_feature_extract_unsigned_field(mmfr0,
+ ID_AA64MMFR0_EL1_BIGEND_SHIFT);
+
+ return val == 0x1;
+}
+
+static __always_inline bool system_supports_fpsimd(void)
+{
+ return !cpus_have_const_cap(ARM64_HAS_NO_FPSIMD);
+}
+
+static inline bool system_uses_hw_pan(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_PAN) &&
+ cpus_have_const_cap(ARM64_HAS_PAN);
+}
+
+static inline bool system_uses_ttbr0_pan(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_SW_TTBR0_PAN) &&
+ !system_uses_hw_pan();
+}
+
+static __always_inline bool system_supports_sve(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_SVE) &&
+ cpus_have_const_cap(ARM64_SVE);
+}
+
+static __always_inline bool system_supports_sme(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_SME) &&
+ cpus_have_const_cap(ARM64_SME);
+}
+
+static __always_inline bool system_supports_fa64(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_SME) &&
+ cpus_have_const_cap(ARM64_SME_FA64);
+}
+
+static __always_inline bool system_supports_tpidr2(void)
+{
+ return system_supports_sme();
+}
+
+static __always_inline bool system_supports_cnp(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_CNP) &&
+ cpus_have_const_cap(ARM64_HAS_CNP);
+}
+
+static inline bool system_supports_address_auth(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_PTR_AUTH) &&
+ cpus_have_const_cap(ARM64_HAS_ADDRESS_AUTH);
+}
+
+static inline bool system_supports_generic_auth(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_PTR_AUTH) &&
+ cpus_have_const_cap(ARM64_HAS_GENERIC_AUTH);
+}
+
+static inline bool system_has_full_ptr_auth(void)
+{
+ return system_supports_address_auth() && system_supports_generic_auth();
+}
+
+static __always_inline bool system_uses_irq_prio_masking(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_PSEUDO_NMI) &&
+ cpus_have_const_cap(ARM64_HAS_IRQ_PRIO_MASKING);
+}
+
+static inline bool system_supports_mte(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_MTE) &&
+ cpus_have_const_cap(ARM64_MTE);
+}
+
+static inline bool system_has_prio_mask_debugging(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_DEBUG_PRIORITY_MASKING) &&
+ system_uses_irq_prio_masking();
+}
+
+static inline bool system_supports_bti(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_BTI) && cpus_have_const_cap(ARM64_BTI);
+}
+
+static inline bool system_supports_tlb_range(void)
+{
+ return IS_ENABLED(CONFIG_ARM64_TLB_RANGE) &&
+ cpus_have_const_cap(ARM64_HAS_TLB_RANGE);
+}
+
+extern int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt);
+
+static inline u32 id_aa64mmfr0_parange_to_phys_shift(int parange)
+{
+ switch (parange) {
+ case ID_AA64MMFR0_EL1_PARANGE_32: return 32;
+ case ID_AA64MMFR0_EL1_PARANGE_36: return 36;
+ case ID_AA64MMFR0_EL1_PARANGE_40: return 40;
+ case ID_AA64MMFR0_EL1_PARANGE_42: return 42;
+ case ID_AA64MMFR0_EL1_PARANGE_44: return 44;
+ case ID_AA64MMFR0_EL1_PARANGE_48: return 48;
+ case ID_AA64MMFR0_EL1_PARANGE_52: return 52;
+ /*
+ * A future PE could use a value unknown to the kernel.
+ * However, by the "D10.1.4 Principles of the ID scheme
+ * for fields in ID registers", ARM DDI 0487C.a, any new
+ * value is guaranteed to be higher than what we know already.
+ * As a safe limit, we return the limit supported by the kernel.
+ */
+ default: return CONFIG_ARM64_PA_BITS;
+ }
+}
+
+/* Check whether hardware update of the Access flag is supported */
+static inline bool cpu_has_hw_af(void)
+{
+ u64 mmfr1;
+
+ if (!IS_ENABLED(CONFIG_ARM64_HW_AFDBM))
+ return false;
+
+ /*
+ * Use cached version to avoid emulated msr operation on KVM
+ * guests.
+ */
+ mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
+ return cpuid_feature_extract_unsigned_field(mmfr1,
+ ID_AA64MMFR1_EL1_HAFDBS_SHIFT);
+}
+
+static inline bool cpu_has_pan(void)
+{
+ u64 mmfr1 = read_cpuid(ID_AA64MMFR1_EL1);
+ return cpuid_feature_extract_unsigned_field(mmfr1,
+ ID_AA64MMFR1_EL1_PAN_SHIFT);
+}
+
+#ifdef CONFIG_ARM64_AMU_EXTN
+/* Check whether the cpu supports the Activity Monitors Unit (AMU) */
+extern bool cpu_has_amu_feat(int cpu);
+#else
+static inline bool cpu_has_amu_feat(int cpu)
+{
+ return false;
+}
+#endif
+
+/* Get a cpu that supports the Activity Monitors Unit (AMU) */
+extern int get_cpu_with_amu_feat(void);
+
+static inline unsigned int get_vmid_bits(u64 mmfr1)
+{
+ int vmid_bits;
+
+ vmid_bits = cpuid_feature_extract_unsigned_field(mmfr1,
+ ID_AA64MMFR1_EL1_VMIDBits_SHIFT);
+ if (vmid_bits == ID_AA64MMFR1_EL1_VMIDBits_16)
+ return 16;
+
+ /*
+ * Return the default here even if any reserved
+ * value is fetched from the system register.
+ */
+ return 8;
+}
+
+struct arm64_ftr_reg *get_arm64_ftr_reg(u32 sys_id);
+
+extern struct arm64_ftr_override id_aa64mmfr1_override;
+extern struct arm64_ftr_override id_aa64pfr0_override;
+extern struct arm64_ftr_override id_aa64pfr1_override;
+extern struct arm64_ftr_override id_aa64zfr0_override;
+extern struct arm64_ftr_override id_aa64smfr0_override;
+extern struct arm64_ftr_override id_aa64isar1_override;
+extern struct arm64_ftr_override id_aa64isar2_override;
+
+u32 get_kvm_ipa_limit(void);
+void dump_cpu_features(void);
+
+#endif /* __ASSEMBLY__ */
+
+#endif