Sasha Smundak | 33d5ddd | 2020-05-04 13:37:26 -0700 | [diff] [blame] | 1 | //===---- arm_cmse.h - Arm CMSE support -----------------------------------===// |
| 2 | // |
| 3 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| 4 | // See https://llvm.org/LICENSE.txt for license information. |
| 5 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| 6 | // |
| 7 | //===----------------------------------------------------------------------===// |
| 8 | |
| 9 | #ifndef __ARM_CMSE_H |
| 10 | #define __ARM_CMSE_H |
| 11 | |
| 12 | #if (__ARM_FEATURE_CMSE & 0x1) |
| 13 | #include <stddef.h> |
| 14 | #include <stdint.h> |
| 15 | |
| 16 | #define __ARM_CMSE_SECURE_MODE (__ARM_FEATURE_CMSE & 0x2) |
| 17 | #define CMSE_MPU_READWRITE 1 /* checks if readwrite_ok field is set */ |
| 18 | #define CMSE_AU_NONSECURE 2 /* checks if permissions have secure field unset */ |
| 19 | #define CMSE_MPU_UNPRIV 4 /* sets T flag on TT insrtuction */ |
| 20 | #define CMSE_MPU_READ 8 /* checks if read_ok field is set */ |
| 21 | #define CMSE_MPU_NONSECURE 16 /* sets A flag, checks if secure field unset */ |
| 22 | #define CMSE_NONSECURE (CMSE_AU_NONSECURE | CMSE_MPU_NONSECURE) |
| 23 | |
| 24 | #define cmse_check_pointed_object(p, f) \ |
| 25 | cmse_check_address_range((p), sizeof(*(p)), (f)) |
| 26 | |
| 27 | #if defined(__cplusplus) |
| 28 | extern "C" { |
| 29 | #endif |
| 30 | |
| 31 | typedef union { |
| 32 | struct cmse_address_info { |
| 33 | #ifdef __ARM_BIG_ENDIAN |
| 34 | /* __ARM_BIG_ENDIAN */ |
| 35 | #if (__ARM_CMSE_SECURE_MODE) |
| 36 | unsigned idau_region : 8; |
| 37 | unsigned idau_region_valid : 1; |
| 38 | unsigned secure : 1; |
| 39 | unsigned nonsecure_readwrite_ok : 1; |
| 40 | unsigned nonsecure_read_ok : 1; |
| 41 | #else |
| 42 | unsigned : 12; |
| 43 | #endif |
| 44 | unsigned readwrite_ok : 1; |
| 45 | unsigned read_ok : 1; |
| 46 | #if (__ARM_CMSE_SECURE_MODE) |
| 47 | unsigned sau_region_valid : 1; |
| 48 | #else |
| 49 | unsigned : 1; |
| 50 | #endif |
| 51 | unsigned mpu_region_valid : 1; |
| 52 | #if (__ARM_CMSE_SECURE_MODE) |
| 53 | unsigned sau_region : 8; |
| 54 | #else |
| 55 | unsigned : 8; |
| 56 | #endif |
| 57 | unsigned mpu_region : 8; |
| 58 | |
| 59 | #else /* __ARM_LITTLE_ENDIAN */ |
| 60 | unsigned mpu_region : 8; |
| 61 | #if (__ARM_CMSE_SECURE_MODE) |
| 62 | unsigned sau_region : 8; |
| 63 | #else |
| 64 | unsigned : 8; |
| 65 | #endif |
| 66 | unsigned mpu_region_valid : 1; |
| 67 | #if (__ARM_CMSE_SECURE_MODE) |
| 68 | unsigned sau_region_valid : 1; |
| 69 | #else |
| 70 | unsigned : 1; |
| 71 | #endif |
| 72 | unsigned read_ok : 1; |
| 73 | unsigned readwrite_ok : 1; |
| 74 | #if (__ARM_CMSE_SECURE_MODE) |
| 75 | unsigned nonsecure_read_ok : 1; |
| 76 | unsigned nonsecure_readwrite_ok : 1; |
| 77 | unsigned secure : 1; |
| 78 | unsigned idau_region_valid : 1; |
| 79 | unsigned idau_region : 8; |
| 80 | #else |
| 81 | unsigned : 12; |
| 82 | #endif |
| 83 | #endif /*__ARM_LITTLE_ENDIAN */ |
| 84 | } flags; |
| 85 | unsigned value; |
| 86 | } cmse_address_info_t; |
| 87 | |
| 88 | static cmse_address_info_t __attribute__((__always_inline__, __nodebug__)) |
| 89 | cmse_TT(void *__p) { |
| 90 | cmse_address_info_t __u; |
| 91 | __u.value = __builtin_arm_cmse_TT(__p); |
| 92 | return __u; |
| 93 | } |
| 94 | static cmse_address_info_t __attribute__((__always_inline__, __nodebug__)) |
| 95 | cmse_TTT(void *__p) { |
| 96 | cmse_address_info_t __u; |
| 97 | __u.value = __builtin_arm_cmse_TTT(__p); |
| 98 | return __u; |
| 99 | } |
| 100 | |
| 101 | #if __ARM_CMSE_SECURE_MODE |
| 102 | static cmse_address_info_t __attribute__((__always_inline__, __nodebug__)) |
| 103 | cmse_TTA(void *__p) { |
| 104 | cmse_address_info_t __u; |
| 105 | __u.value = __builtin_arm_cmse_TTA(__p); |
| 106 | return __u; |
| 107 | } |
| 108 | static cmse_address_info_t __attribute__((__always_inline__, __nodebug__)) |
| 109 | cmse_TTAT(void *__p) { |
| 110 | cmse_address_info_t __u; |
| 111 | __u.value = __builtin_arm_cmse_TTAT(__p); |
| 112 | return __u; |
| 113 | } |
| 114 | #endif |
| 115 | |
| 116 | #define cmse_TT_fptr(p) cmse_TT(__builtin_bit_cast(void *, (p))) |
| 117 | #define cmse_TTT_fptr(p) cmse_TTT(__builtin_bit_cast(void *, (p))) |
| 118 | |
| 119 | #if __ARM_CMSE_SECURE_MODE |
| 120 | #define cmse_TTA_fptr(p) cmse_TTA(__builtin_bit_cast(void *, (p))) |
| 121 | #define cmse_TTAT_fptr(p) cmse_TTAT(__builtin_bit_cast(void *, (p))) |
| 122 | #endif |
| 123 | |
| 124 | static void *__attribute__((__always_inline__)) |
| 125 | cmse_check_address_range(void *__pb, size_t __s, int __flags) { |
| 126 | uintptr_t __begin = (uintptr_t)__pb; |
| 127 | uintptr_t __end = __begin + __s - 1; |
| 128 | |
| 129 | if (__end < __begin) |
| 130 | return NULL; /* wrap around check */ |
| 131 | |
| 132 | /* Check whether the range crosses a 32-bytes aligned address */ |
| 133 | const int __single_check = (__begin ^ __end) < 0x20u; |
| 134 | |
| 135 | /* execute the right variant of the TT instructions */ |
| 136 | void *__pe = (void *)__end; |
| 137 | cmse_address_info_t __permb, __perme; |
| 138 | switch (__flags & (CMSE_MPU_UNPRIV | CMSE_MPU_NONSECURE)) { |
| 139 | case 0: |
| 140 | __permb = cmse_TT(__pb); |
| 141 | __perme = __single_check ? __permb : cmse_TT(__pe); |
| 142 | break; |
| 143 | case CMSE_MPU_UNPRIV: |
| 144 | __permb = cmse_TTT(__pb); |
| 145 | __perme = __single_check ? __permb : cmse_TTT(__pe); |
| 146 | break; |
| 147 | #if __ARM_CMSE_SECURE_MODE |
| 148 | case CMSE_MPU_NONSECURE: |
| 149 | __permb = cmse_TTA(__pb); |
| 150 | __perme = __single_check ? __permb : cmse_TTA(__pe); |
| 151 | break; |
| 152 | case CMSE_MPU_UNPRIV | CMSE_MPU_NONSECURE: |
| 153 | __permb = cmse_TTAT(__pb); |
| 154 | __perme = __single_check ? __permb : cmse_TTAT(__pe); |
| 155 | break; |
| 156 | #endif |
| 157 | /* if CMSE_NONSECURE is specified w/o __ARM_CMSE_SECURE_MODE */ |
| 158 | default: |
| 159 | return NULL; |
| 160 | } |
| 161 | |
| 162 | /* check that the range does not cross MPU, SAU, or IDAU region boundaries */ |
| 163 | if (__permb.value != __perme.value) |
| 164 | return NULL; |
| 165 | #if !(__ARM_CMSE_SECURE_MODE) |
| 166 | /* CMSE_AU_NONSECURE is only supported when __ARM_FEATURE_CMSE & 0x2 */ |
| 167 | if (__flags & CMSE_AU_NONSECURE) |
| 168 | return NULL; |
| 169 | #endif |
| 170 | |
| 171 | /* check the permission on the range */ |
| 172 | switch (__flags & ~(CMSE_MPU_UNPRIV | CMSE_MPU_NONSECURE)) { |
| 173 | #if (__ARM_CMSE_SECURE_MODE) |
| 174 | case CMSE_MPU_READ | CMSE_MPU_READWRITE | CMSE_AU_NONSECURE: |
| 175 | case CMSE_MPU_READWRITE | CMSE_AU_NONSECURE: |
| 176 | return __permb.flags.nonsecure_readwrite_ok ? __pb : NULL; |
| 177 | |
| 178 | case CMSE_MPU_READ | CMSE_AU_NONSECURE: |
| 179 | return __permb.flags.nonsecure_read_ok ? __pb : NULL; |
| 180 | |
| 181 | case CMSE_AU_NONSECURE: |
| 182 | return __permb.flags.secure ? NULL : __pb; |
| 183 | #endif |
| 184 | case CMSE_MPU_READ | CMSE_MPU_READWRITE: |
| 185 | case CMSE_MPU_READWRITE: |
| 186 | return __permb.flags.readwrite_ok ? __pb : NULL; |
| 187 | |
| 188 | case CMSE_MPU_READ: |
| 189 | return __permb.flags.read_ok ? __pb : NULL; |
| 190 | |
| 191 | default: |
| 192 | return NULL; |
| 193 | } |
| 194 | } |
| 195 | |
| 196 | #if __ARM_CMSE_SECURE_MODE |
| 197 | static int __attribute__((__always_inline__, __nodebug__)) |
| 198 | cmse_nonsecure_caller(void) { |
| 199 | return !((uintptr_t)__builtin_return_address(0) & 1); |
| 200 | } |
| 201 | |
| 202 | #define cmse_nsfptr_create(p) \ |
| 203 | __builtin_bit_cast(__typeof__(p), \ |
| 204 | (__builtin_bit_cast(uintptr_t, p) & ~(uintptr_t)1)) |
| 205 | |
| 206 | #define cmse_is_nsfptr(p) ((__builtin_bit_cast(uintptr_t, p) & 1) == 0) |
| 207 | |
| 208 | #endif /* __ARM_CMSE_SECURE_MODE */ |
| 209 | |
| 210 | void __attribute__((__noreturn__)) cmse_abort(void); |
| 211 | #if defined(__cplusplus) |
| 212 | } |
| 213 | #endif |
| 214 | |
| 215 | #endif /* (__ARM_FEATURE_CMSE & 0x1) */ |
| 216 | |
| 217 | #endif /* __ARM_CMSE_H */ |