xref: /linux/arch/arm/include/asm/virt.h (revision a4eb44a6435d6d8f9e642407a4a06f65eb90ca04)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * Copyright (c) 2012 Linaro Limited.
4  */
5 
6 #ifndef VIRT_H
7 #define VIRT_H
8 
9 #include <asm/ptrace.h>
10 
11 /*
12  * Flag indicating that the kernel was not entered in the same mode on every
13  * CPU.  The zImage loader stashes this value in an SPSR, so we need an
14  * architecturally defined flag bit here.
15  */
16 #define BOOT_CPU_MODE_MISMATCH	PSR_N_BIT
17 
18 #ifndef __ASSEMBLY__
19 #include <asm/cacheflush.h>
20 
21 #ifdef CONFIG_ARM_VIRT_EXT
22 /*
23  * __boot_cpu_mode records what mode the primary CPU was booted in.
24  * A correctly-implemented bootloader must start all CPUs in the same mode:
25  * if it fails to do this, the flag BOOT_CPU_MODE_MISMATCH is set to indicate
26  * that some CPU(s) were booted in a different mode.
27  *
28  * This allows the kernel to flag an error when the secondaries have come up.
29  */
30 extern int __boot_cpu_mode;
31 
32 static inline void sync_boot_mode(void)
33 {
34 	/*
35 	 * As secondaries write to __boot_cpu_mode with caches disabled, we
36 	 * must flush the corresponding cache entries to ensure the visibility
37 	 * of their writes.
38 	 */
39 	sync_cache_r(&__boot_cpu_mode);
40 }
41 
42 #else
43 #define __boot_cpu_mode	(SVC_MODE)
44 #define sync_boot_mode()
45 #endif
46 
47 #ifndef ZIMAGE
48 void hyp_mode_check(void);
49 
50 /* Reports the availability of HYP mode */
51 static inline bool is_hyp_mode_available(void)
52 {
53 	return ((__boot_cpu_mode & MODE_MASK) == HYP_MODE &&
54 		!(__boot_cpu_mode & BOOT_CPU_MODE_MISMATCH));
55 }
56 
57 /* Check if the bootloader has booted CPUs in different modes */
58 static inline bool is_hyp_mode_mismatched(void)
59 {
60 	return !!(__boot_cpu_mode & BOOT_CPU_MODE_MISMATCH);
61 }
62 
63 static inline bool is_kernel_in_hyp_mode(void)
64 {
65 	return false;
66 }
67 
68 #endif
69 
70 #else
71 
72 /* Only assembly code should need those */
73 
74 #define HVC_SET_VECTORS 0
75 #define HVC_SOFT_RESTART 1
76 
77 #endif /* __ASSEMBLY__ */
78 
79 #define HVC_STUB_ERR	0xbadca11
80 
81 #endif /* ! VIRT_H */
82