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 */
63extern u32 __boot_cpu_mode[2];
64
65void __hyp_set_vectors(phys_addr_t phys_vector_base);
66void __hyp_reset_vectors(void);
67
68/* Reports the availability of HYP mode */
69static 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 */
76static inline bool is_hyp_mode_mismatched(void)
77{
78	return __boot_cpu_mode[0] != __boot_cpu_mode[1];
79}
80
81static inline bool is_kernel_in_hyp_mode(void)
82{
83	return read_sysreg(CurrentEL) == CurrentEL_EL2;
84}
85
86static __always_inline bool has_vhe(void)
87{
88	/*
89	 * Code only run in VHE/NVHE hyp context can assume VHE is present or
90	 * absent. Otherwise fall back to caps.
91	 */
92	if (is_vhe_hyp_code())
93		return true;
94	else if (is_nvhe_hyp_code())
95		return false;
96	else
97		return cpus_have_final_cap(ARM64_HAS_VIRT_HOST_EXTN);
98}
99
100#endif /* __ASSEMBLY__ */
101
102#endif /* ! __ASM__VIRT_H */
103