1 /* SPDX-License-Identifier: GPL-2.0-only */
3 * Copyright (C) 2012 ARM Ltd.
4 * Author: Marc Zyngier <marc.zyngier@arm.com>
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.
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).
22 * HVC_SET_VECTORS - Set the value of the vbar_el2 register.
24 * @x1: Physical address of the new vector table.
26 #define HVC_SET_VECTORS 0
29 * HVC_SOFT_RESTART - CPU soft reset, used by the cpu_soft_restart routine.
31 #define HVC_SOFT_RESTART 1
34 * HVC_RESET_VECTORS - Restore the vectors to the original HYP stubs
36 #define HVC_RESET_VECTORS 2
39 * HVC_FINALISE_EL2 - Upgrade the CPU from EL1 to EL2, if possible
41 #define HVC_FINALISE_EL2 3
43 /* Max number of HYP stub hypercalls */
44 #define HVC_STUB_HCALL_NR 4
46 /* Error returned when an invalid stub number is passed into x0 */
47 #define HVC_STUB_ERR 0xbadca11
49 #define BOOT_CPU_MODE_EL1 (0xe11)
50 #define BOOT_CPU_MODE_EL2 (0xe12)
53 * Flags returned together with the boot mode, but not preserved in
54 * __boot_cpu_mode. Used by the idreg override code to work out the
57 #define BOOT_CPU_FLAG_E2H BIT_ULL(32)
61 #include <asm/ptrace.h>
62 #include <asm/sections.h>
63 #include <asm/sysreg.h>
64 #include <asm/cpufeature.h>
67 * __boot_cpu_mode records what mode CPUs were booted in.
68 * A correctly-implemented bootloader must start all CPUs in the same mode:
69 * In this case, both 32bit halves of __boot_cpu_mode will contain the
70 * same value (either 0 if booted in EL1, BOOT_CPU_MODE_EL2 if booted in EL2).
72 * Should the bootloader fail to do this, the two values will be different.
73 * This allows the kernel to flag an error when the secondaries have come up.
75 extern u32 __boot_cpu_mode[2];
77 #define ARM64_VECTOR_TABLE_LEN SZ_2K
79 void __hyp_set_vectors(phys_addr_t phys_vector_base);
80 void __hyp_reset_vectors(void);
81 bool is_kvm_arm_initialised(void);
83 DECLARE_STATIC_KEY_FALSE(kvm_protected_mode_initialized);
85 /* Reports the availability of HYP mode */
86 static inline bool is_hyp_mode_available(void)
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.
92 if (IS_ENABLED(CONFIG_KVM) &&
93 static_branch_likely(&kvm_protected_mode_initialized))
96 return (__boot_cpu_mode[0] == BOOT_CPU_MODE_EL2 &&
97 __boot_cpu_mode[1] == BOOT_CPU_MODE_EL2);
100 /* Check if the bootloader has booted CPUs in different modes */
101 static inline bool is_hyp_mode_mismatched(void)
104 * If KVM protected mode is initialized, all CPUs must have been booted
105 * in EL2. Avoid checking __boot_cpu_mode as CPUs now come up in EL1.
107 if (IS_ENABLED(CONFIG_KVM) &&
108 static_branch_likely(&kvm_protected_mode_initialized))
111 return __boot_cpu_mode[0] != __boot_cpu_mode[1];
114 static __always_inline bool is_kernel_in_hyp_mode(void)
116 BUILD_BUG_ON(__is_defined(__KVM_NVHE_HYPERVISOR__) ||
117 __is_defined(__KVM_VHE_HYPERVISOR__));
118 return read_sysreg(CurrentEL) == CurrentEL_EL2;
121 static __always_inline bool has_vhe(void)
124 * Code only run in VHE/NVHE hyp context can assume VHE is present or
125 * absent. Otherwise fall back to caps.
126 * This allows the compiler to discard VHE-specific code from the
127 * nVHE object, reducing the number of external symbol references
130 if (is_vhe_hyp_code())
132 else if (is_nvhe_hyp_code())
135 return cpus_have_final_cap(ARM64_HAS_VIRT_HOST_EXTN);
138 static __always_inline bool is_protected_kvm_enabled(void)
140 if (is_vhe_hyp_code())
143 return cpus_have_final_cap(ARM64_KVM_PROTECTED_MODE);
146 static __always_inline bool has_hvhe(void)
148 if (is_vhe_hyp_code())
151 return cpus_have_final_cap(ARM64_KVM_HVHE);
154 static inline bool is_hyp_nvhe(void)
156 return is_hyp_mode_available() && !is_kernel_in_hyp_mode();
159 #endif /* __ASSEMBLY__ */
161 #endif /* ! __ASM__VIRT_H */