1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Copyright (C) 2012 ARM Ltd. 4 * Author: Marc Zyngier <marc.zyngier@arm.com> 5 */ 6 7 #ifndef __ASM__VIRT_H 8 #define __ASM__VIRT_H 9 10 /* 11 * The arm64 hcall implementation uses x0 to specify the hcall 12 * number. A value less than HVC_STUB_HCALL_NR indicates a special 13 * hcall, such as set vector. Any other value is handled in a 14 * hypervisor specific way. 15 * 16 * The hypercall is allowed to clobber any of the caller-saved 17 * registers (x0-x18), so it is advisable to use it through the 18 * indirection of a function call (as implemented in hyp-stub.S). 19 */ 20 21 /* 22 * HVC_SET_VECTORS - Set the value of the vbar_el2 register. 23 * 24 * @x1: Physical address of the new vector table. 25 */ 26 #define HVC_SET_VECTORS 0 27 28 /* 29 * HVC_SOFT_RESTART - CPU soft reset, used by the cpu_soft_restart routine. 30 */ 31 #define HVC_SOFT_RESTART 1 32 33 /* 34 * HVC_RESET_VECTORS - Restore the vectors to the original HYP stubs 35 */ 36 #define HVC_RESET_VECTORS 2 37 38 /* 39 * HVC_FINALISE_EL2 - Upgrade the CPU from EL1 to EL2, if possible 40 */ 41 #define HVC_FINALISE_EL2 3 42 43 /* 44 * HVC_GET_ICH_VTR_EL2 - Retrieve the ICH_VTR_EL2 value 45 */ 46 #define HVC_GET_ICH_VTR_EL2 4 47 48 /* Max number of HYP stub hypercalls */ 49 #define HVC_STUB_HCALL_NR 5 50 51 /* Error returned when an invalid stub number is passed into x0 */ 52 #define HVC_STUB_ERR 0xbadca11 53 54 #define BOOT_CPU_MODE_EL1 (0xe11) 55 #define BOOT_CPU_MODE_EL2 (0xe12) 56 57 /* 58 * Flags returned together with the boot mode, but not preserved in 59 * __boot_cpu_mode. Used by the idreg override code to work out the 60 * boot state. 61 */ 62 #define BOOT_CPU_FLAG_E2H BIT_ULL(32) 63 64 #ifndef __ASSEMBLER__ 65 66 #include <asm/ptrace.h> 67 #include <asm/sections.h> 68 #include <asm/sysreg.h> 69 #include <asm/cpufeature.h> 70 71 /* 72 * __boot_cpu_mode records what mode CPUs were booted in. 73 * A correctly-implemented bootloader must start all CPUs in the same mode: 74 * In this case, both 32bit halves of __boot_cpu_mode will contain the 75 * same value (either BOOT_CPU_MODE_EL1 if booted in EL1, BOOT_CPU_MODE_EL2 if 76 * booted in EL2). 77 * 78 * Should the bootloader fail to do this, the two values will be different. 79 * This allows the kernel to flag an error when the secondaries have come up. 80 */ 81 extern u32 __boot_cpu_mode[2]; 82 83 #define ARM64_VECTOR_TABLE_LEN SZ_2K 84 85 void __hyp_set_vectors(phys_addr_t phys_vector_base); 86 void __hyp_reset_vectors(void); 87 bool is_kvm_arm_initialised(void); 88 89 DECLARE_STATIC_KEY_FALSE(kvm_protected_mode_initialized); 90 91 static inline bool is_pkvm_initialized(void) 92 { 93 return IS_ENABLED(CONFIG_KVM) && 94 static_branch_likely(&kvm_protected_mode_initialized); 95 } 96 97 #ifdef CONFIG_KVM 98 bool pkvm_force_reclaim_guest_page(phys_addr_t phys); 99 #else 100 static inline bool pkvm_force_reclaim_guest_page(phys_addr_t phys) 101 { 102 return false; 103 } 104 #endif 105 106 /* Reports the availability of HYP mode */ 107 static inline bool is_hyp_mode_available(void) 108 { 109 /* 110 * If KVM protected mode is initialized, all CPUs must have been booted 111 * in EL2. Avoid checking __boot_cpu_mode as CPUs now come up in EL1. 112 */ 113 if (is_pkvm_initialized()) 114 return true; 115 116 return (__boot_cpu_mode[0] == BOOT_CPU_MODE_EL2 && 117 __boot_cpu_mode[1] == BOOT_CPU_MODE_EL2); 118 } 119 120 /* Check if the bootloader has booted CPUs in different modes */ 121 static inline bool is_hyp_mode_mismatched(void) 122 { 123 /* 124 * If KVM protected mode is initialized, all CPUs must have been booted 125 * in EL2. Avoid checking __boot_cpu_mode as CPUs now come up in EL1. 126 */ 127 if (is_pkvm_initialized()) 128 return false; 129 130 return __boot_cpu_mode[0] != __boot_cpu_mode[1]; 131 } 132 133 static __always_inline bool is_kernel_in_hyp_mode(void) 134 { 135 BUILD_BUG_ON(__is_defined(__KVM_NVHE_HYPERVISOR__) || 136 __is_defined(__KVM_VHE_HYPERVISOR__)); 137 return read_sysreg(CurrentEL) == CurrentEL_EL2; 138 } 139 140 static __always_inline bool has_vhe(void) 141 { 142 /* 143 * Code only run in VHE/NVHE hyp context can assume VHE is present or 144 * absent. Otherwise fall back to caps. 145 * This allows the compiler to discard VHE-specific code from the 146 * nVHE object, reducing the number of external symbol references 147 * needed to link. 148 */ 149 if (is_vhe_hyp_code()) 150 return true; 151 else if (is_nvhe_hyp_code()) 152 return false; 153 else 154 return cpus_have_final_cap(ARM64_HAS_VIRT_HOST_EXTN); 155 } 156 157 static __always_inline bool is_protected_kvm_enabled(void) 158 { 159 if (is_vhe_hyp_code()) 160 return false; 161 else 162 return cpus_have_final_cap(ARM64_KVM_PROTECTED_MODE); 163 } 164 165 static __always_inline bool has_hvhe(void) 166 { 167 if (is_vhe_hyp_code()) 168 return false; 169 170 return cpus_have_final_cap(ARM64_KVM_HVHE); 171 } 172 173 static inline bool is_hyp_nvhe(void) 174 { 175 return is_hyp_mode_available() && !is_kernel_in_hyp_mode(); 176 } 177 178 #endif /* __ASSEMBLER__ */ 179 180 #endif /* ! __ASM__VIRT_H */ 181