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 /* Max number of HYP stub hypercalls */ 39 #define HVC_STUB_HCALL_NR 3 40 41 /* Error returned when an invalid stub number is passed into x0 */ 42 #define HVC_STUB_ERR 0xbadca11 43 44 #define BOOT_CPU_MODE_EL1 (0xe11) 45 #define BOOT_CPU_MODE_EL2 (0xe12) 46 47 #ifndef __ASSEMBLY__ 48 49 #include <asm/ptrace.h> 50 #include <asm/sections.h> 51 #include <asm/sysreg.h> 52 #include <asm/cpufeature.h> 53 54 /* 55 * __boot_cpu_mode records what mode CPUs were booted in. 56 * A correctly-implemented bootloader must start all CPUs in the same mode: 57 * In this case, both 32bit halves of __boot_cpu_mode will contain the 58 * same value (either 0 if booted in EL1, BOOT_CPU_MODE_EL2 if booted in EL2). 59 * 60 * Should the bootloader fail to do this, the two values will be different. 61 * This allows the kernel to flag an error when the secondaries have come up. 62 */ 63 extern u32 __boot_cpu_mode[2]; 64 65 void __hyp_set_vectors(phys_addr_t phys_vector_base); 66 void __hyp_reset_vectors(void); 67 68 DECLARE_STATIC_KEY_FALSE(kvm_protected_mode_initialized); 69 70 /* Reports the availability of HYP mode */ 71 static inline bool is_hyp_mode_available(void) 72 { 73 /* 74 * If KVM protected mode is initialized, all CPUs must have been booted 75 * in EL2. Avoid checking __boot_cpu_mode as CPUs now come up in EL1. 76 */ 77 if (IS_ENABLED(CONFIG_KVM) && 78 static_branch_likely(&kvm_protected_mode_initialized)) 79 return true; 80 81 return (__boot_cpu_mode[0] == BOOT_CPU_MODE_EL2 && 82 __boot_cpu_mode[1] == BOOT_CPU_MODE_EL2); 83 } 84 85 /* Check if the bootloader has booted CPUs in different modes */ 86 static inline bool is_hyp_mode_mismatched(void) 87 { 88 /* 89 * If KVM protected mode is initialized, all CPUs must have been booted 90 * in EL2. Avoid checking __boot_cpu_mode as CPUs now come up in EL1. 91 */ 92 if (IS_ENABLED(CONFIG_KVM) && 93 static_branch_likely(&kvm_protected_mode_initialized)) 94 return false; 95 96 return __boot_cpu_mode[0] != __boot_cpu_mode[1]; 97 } 98 99 static inline bool is_kernel_in_hyp_mode(void) 100 { 101 return read_sysreg(CurrentEL) == CurrentEL_EL2; 102 } 103 104 static __always_inline bool has_vhe(void) 105 { 106 /* 107 * Code only run in VHE/NVHE hyp context can assume VHE is present or 108 * absent. Otherwise fall back to caps. 109 */ 110 if (is_vhe_hyp_code()) 111 return true; 112 else if (is_nvhe_hyp_code()) 113 return false; 114 else 115 return cpus_have_final_cap(ARM64_HAS_VIRT_HOST_EXTN); 116 } 117 118 static __always_inline bool is_protected_kvm_enabled(void) 119 { 120 if (is_vhe_hyp_code()) 121 return false; 122 else 123 return cpus_have_final_cap(ARM64_KVM_PROTECTED_MODE); 124 } 125 126 #endif /* __ASSEMBLY__ */ 127 128 #endif /* ! __ASM__VIRT_H */ 129