xref: /openbmc/linux/arch/arm64/include/asm/virt.h (revision 32981ea5)
1 /*
2  * Copyright (C) 2012 ARM Ltd.
3  * Author: Marc Zyngier <marc.zyngier@arm.com>
4  *
5  * This program is free software: you can redistribute it and/or modify
6  * it under the terms of the GNU General Public License version 2 as
7  * published by the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12  * GNU General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License
15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #ifndef __ASM__VIRT_H
19 #define __ASM__VIRT_H
20 
21 /*
22  * The arm64 hcall implementation uses x0 to specify the hcall type. A value
23  * less than 0xfff indicates a special hcall, such as get/set vector.
24  * Any other value is used as a pointer to the function to call.
25  */
26 
27 /* HVC_GET_VECTORS - Return the value of the vbar_el2 register. */
28 #define HVC_GET_VECTORS 0
29 
30 /*
31  * HVC_SET_VECTORS - Set the value of the vbar_el2 register.
32  *
33  * @x1: Physical address of the new vector table.
34  */
35 #define HVC_SET_VECTORS 1
36 
37 #define BOOT_CPU_MODE_EL1	(0xe11)
38 #define BOOT_CPU_MODE_EL2	(0xe12)
39 
40 #ifndef __ASSEMBLY__
41 
42 #include <asm/ptrace.h>
43 
44 /*
45  * __boot_cpu_mode records what mode CPUs were booted in.
46  * A correctly-implemented bootloader must start all CPUs in the same mode:
47  * In this case, both 32bit halves of __boot_cpu_mode will contain the
48  * same value (either 0 if booted in EL1, BOOT_CPU_MODE_EL2 if booted in EL2).
49  *
50  * Should the bootloader fail to do this, the two values will be different.
51  * This allows the kernel to flag an error when the secondaries have come up.
52  */
53 extern u32 __boot_cpu_mode[2];
54 
55 void __hyp_set_vectors(phys_addr_t phys_vector_base);
56 phys_addr_t __hyp_get_vectors(void);
57 
58 /* Reports the availability of HYP mode */
59 static inline bool is_hyp_mode_available(void)
60 {
61 	return (__boot_cpu_mode[0] == BOOT_CPU_MODE_EL2 &&
62 		__boot_cpu_mode[1] == BOOT_CPU_MODE_EL2);
63 }
64 
65 /* Check if the bootloader has booted CPUs in different modes */
66 static inline bool is_hyp_mode_mismatched(void)
67 {
68 	return __boot_cpu_mode[0] != __boot_cpu_mode[1];
69 }
70 
71 static inline bool is_kernel_in_hyp_mode(void)
72 {
73 	u64 el;
74 
75 	asm("mrs %0, CurrentEL" : "=r" (el));
76 	return el == CurrentEL_EL2;
77 }
78 
79 #ifdef CONFIG_ARM64_VHE
80 extern void verify_cpu_run_el(void);
81 #else
82 static inline void verify_cpu_run_el(void) {}
83 #endif
84 
85 /* The section containing the hypervisor text */
86 extern char __hyp_text_start[];
87 extern char __hyp_text_end[];
88 
89 #endif /* __ASSEMBLY__ */
90 
91 #endif /* ! __ASM__VIRT_H */
92