218 lines · c
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-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef __ARM_CMSE_H10#define __ARM_CMSE_H11 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)28extern "C" {29#endif30 31typedef union {32 struct cmse_address_info {33#ifdef __ARM_BIG_ENDIAN34 /* __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#else42 unsigned : 12;43#endif44 unsigned readwrite_ok : 1;45 unsigned read_ok : 1;46#if (__ARM_CMSE_SECURE_MODE)47 unsigned sau_region_valid : 1;48#else49 unsigned : 1;50#endif51 unsigned mpu_region_valid : 1;52#if (__ARM_CMSE_SECURE_MODE)53 unsigned sau_region : 8;54#else55 unsigned : 8;56#endif57 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#else64 unsigned : 8;65#endif66 unsigned mpu_region_valid : 1;67#if (__ARM_CMSE_SECURE_MODE)68 unsigned sau_region_valid : 1;69#else70 unsigned : 1;71#endif72 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#else81 unsigned : 12;82#endif83#endif /*__ARM_LITTLE_ENDIAN */84 } flags;85 unsigned value;86} cmse_address_info_t;87 88static cmse_address_info_t __attribute__((__always_inline__, __nodebug__))89cmse_TT(void *__p) {90 cmse_address_info_t __u;91 __u.value = __builtin_arm_cmse_TT(__p);92 return __u;93}94static cmse_address_info_t __attribute__((__always_inline__, __nodebug__))95cmse_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_MODE102static cmse_address_info_t __attribute__((__always_inline__, __nodebug__))103cmse_TTA(void *__p) {104 cmse_address_info_t __u;105 __u.value = __builtin_arm_cmse_TTA(__p);106 return __u;107}108static cmse_address_info_t __attribute__((__always_inline__, __nodebug__))109cmse_TTAT(void *__p) {110 cmse_address_info_t __u;111 __u.value = __builtin_arm_cmse_TTAT(__p);112 return __u;113}114#endif115 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_MODE120#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#endif123 124static void *__attribute__((__always_inline__))125cmse_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_MODE148 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#endif157 /* 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#endif170 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#endif184 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_MODE197static int __attribute__((__always_inline__, __nodebug__))198cmse_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 210void __attribute__((__noreturn__)) cmse_abort(void);211#if defined(__cplusplus)212}213#endif214 215#endif /* (__ARM_FEATURE_CMSE & 0x1) */216 217#endif /* __ARM_CMSE_H */218