1 /*
2 * Copyright (c) 2013-2025, Arm Limited and Contributors. All rights reserved.
3 *
4 * SPDX-License-Identifier: BSD-3-Clause
5 */
6
7 #ifndef CONTEXT_MGMT_H
8 #define CONTEXT_MGMT_H
9
10 #include <assert.h>
11 #include <context.h>
12 #include <stdint.h>
13
14 #include <arch.h>
15
16 /*******************************************************************************
17 * Forward declarations
18 ******************************************************************************/
19 struct entry_point_info;
20
21 /*******************************************************************************
22 * Function & variable prototypes
23 ******************************************************************************/
24 void cm_init(void);
25 void *cm_get_context_by_index(unsigned int cpu_idx,
26 size_t security_state);
27 void cm_set_context_by_index(unsigned int cpu_idx,
28 void *context,
29 unsigned int security_state);
30 void *cm_get_context(size_t security_state);
31 void cm_set_context(void *context, uint32_t security_state);
32 void cm_init_my_context(const struct entry_point_info *ep);
33 void cm_setup_context(cpu_context_t *ctx, const struct entry_point_info *ep);
34 void cm_prepare_el3_exit(size_t security_state);
35 void cm_prepare_el3_exit_ns(void);
36
37 #ifdef __aarch64__
38 void cm_manage_extensions_el3(unsigned int my_idx);
39 void cm_manage_extensions_per_world(void);
40 void cm_init_percpu_once_regs(void);
41
42 #if (CTX_INCLUDE_EL2_REGS && IMAGE_BL31)
43 void cm_el2_sysregs_context_save(uint32_t security_state);
44 void cm_el2_sysregs_context_restore(uint32_t security_state);
45 #else
46 void cm_el1_sysregs_context_save(uint32_t security_state);
47 void cm_el1_sysregs_context_restore(uint32_t security_state);
48 #endif /* (CTX_INCLUDE_EL2_REGS && IMAGE_BL31) */
49
50 void cm_set_elr_el3(uint32_t security_state, uintptr_t entrypoint);
51 void cm_set_elr_spsr_el3(uint32_t security_state,
52 uintptr_t entrypoint, uint32_t spsr);
53 void cm_write_scr_el3_bit(uint32_t security_state,
54 uint32_t bit_pos,
55 uint32_t value);
56 void cm_set_next_eret_context(uint32_t security_state);
57 u_register_t cm_get_scr_el3(uint32_t security_state);
58
59 /* Inline definitions */
60
61 /*******************************************************************************
62 * This function is used to program the context that's used for exception
63 * return. This initializes the SP_EL3 to a pointer to a 'cpu_context' set for
64 * the required security state
65 ******************************************************************************/
cm_set_next_context(void * context)66 static inline void cm_set_next_context(void *context)
67 {
68 #if ENABLE_ASSERTIONS
69 uint64_t sp_mode;
70
71 /*
72 * Check that this function is called with SP_EL0 as the stack
73 * pointer
74 */
75 __asm__ volatile("mrs %0, SPSel\n"
76 : "=r" (sp_mode));
77
78 assert(sp_mode == MODE_SP_EL0);
79 #endif /* ENABLE_ASSERTIONS */
80
81 __asm__ volatile("msr spsel, #1\n"
82 "mov sp, %0\n"
83 "msr spsel, #0\n"
84 : : "r" (context));
85 }
86
87 #else
88 void *cm_get_next_context(void);
89 void cm_set_next_context(void *context);
cm_manage_extensions_el3(unsigned int cpu_idx)90 static inline void cm_manage_extensions_el3(unsigned int cpu_idx) {}
cm_manage_extensions_per_world(void)91 static inline void cm_manage_extensions_per_world(void) {}
cm_init_percpu_once_regs(void)92 static inline void cm_init_percpu_once_regs(void) {}
93 #endif /* __aarch64__ */
94
95 #endif /* CONTEXT_MGMT_H */
96