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 /* Reports the availability of HYP mode */
69 static inline bool is_hyp_mode_available(void)
70 {
71 return (__boot_cpu_mode[0] == BOOT_CPU_MODE_EL2 &&
72 __boot_cpu_mode[1] == BOOT_CPU_MODE_EL2);
73 }
74
75 /* Check if the bootloader has booted CPUs in different modes */
76 static inline bool is_hyp_mode_mismatched(void)
77 {
78 return __boot_cpu_mode[0] != __boot_cpu_mode[1];
79 }
80
81 static inline bool is_kernel_in_hyp_mode(void)
82 {
83 return read_sysreg(CurrentEL) == CurrentEL_EL2;
84 }
85
86 static inline bool has_vhe(void)
87 {
88 if (cpus_have_const_cap(ARM64_HAS_VIRT_HOST_EXTN))
89 return true;
90
91 return false;
92 }
93
94 #endif /* __ASSEMBLY__ */
95
96 #endif /* ! __ASM__VIRT_H */