1 /* SPDX-License-Identifier: LGPL-2.1 OR MIT */ 2 /* 3 * SuperH specific definitions for NOLIBC 4 * Copyright (C) 2025 Thomas Weißschuh <linux@weissschuh.net> 5 */ 6 7 #ifndef _NOLIBC_ARCH_SH_H 8 #define _NOLIBC_ARCH_SH_H 9 10 #include "compiler.h" 11 #include "crt.h" 12 13 #include <linux/unistd.h> 14 15 /* 16 * Syscalls for SuperH: 17 * - registers are 32bit wide 18 * - syscall number is passed in r3 19 * - arguments are in r4, r5, r6, r7, r0, r1, r2 20 * - the system call is performed by calling trapa #31 21 * - syscall return value is in r0 22 */ 23 24 #define __nolibc_syscall0(num) \ 25 ({ \ 26 register long _num __asm__ ("r3") = (num); \ 27 register long _ret __asm__ ("r0"); \ 28 \ 29 __asm__ volatile ( \ 30 "trapa #31" \ 31 : "=r"(_ret) \ 32 : "r"(_num) \ 33 : "memory", "cc" \ 34 ); \ 35 _ret; \ 36 }) 37 38 #define __nolibc_syscall1(num, arg1) \ 39 ({ \ 40 register long _num __asm__ ("r3") = (num); \ 41 register long _ret __asm__ ("r0"); \ 42 register long _arg1 __asm__ ("r4") = (long)(arg1); \ 43 \ 44 __asm__ volatile ( \ 45 "trapa #31" \ 46 : "=r"(_ret) \ 47 : "r"(_num), "r"(_arg1) \ 48 : "memory", "cc" \ 49 ); \ 50 _ret; \ 51 }) 52 53 #define __nolibc_syscall2(num, arg1, arg2) \ 54 ({ \ 55 register long _num __asm__ ("r3") = (num); \ 56 register long _ret __asm__ ("r0"); \ 57 register long _arg1 __asm__ ("r4") = (long)(arg1); \ 58 register long _arg2 __asm__ ("r5") = (long)(arg2); \ 59 \ 60 __asm__ volatile ( \ 61 "trapa #31" \ 62 : "=r"(_ret) \ 63 : "r"(_num), "r"(_arg1), "r"(_arg2) \ 64 : "memory", "cc" \ 65 ); \ 66 _ret; \ 67 }) 68 69 #define __nolibc_syscall3(num, arg1, arg2, arg3) \ 70 ({ \ 71 register long _num __asm__ ("r3") = (num); \ 72 register long _ret __asm__ ("r0"); \ 73 register long _arg1 __asm__ ("r4") = (long)(arg1); \ 74 register long _arg2 __asm__ ("r5") = (long)(arg2); \ 75 register long _arg3 __asm__ ("r6") = (long)(arg3); \ 76 \ 77 __asm__ volatile ( \ 78 "trapa #31" \ 79 : "=r"(_ret) \ 80 : "r"(_num), "r"(_arg1), "r"(_arg2), "r"(_arg3) \ 81 : "memory", "cc" \ 82 ); \ 83 _ret; \ 84 }) 85 86 #define __nolibc_syscall4(num, arg1, arg2, arg3, arg4) \ 87 ({ \ 88 register long _num __asm__ ("r3") = (num); \ 89 register long _ret __asm__ ("r0"); \ 90 register long _arg1 __asm__ ("r4") = (long)(arg1); \ 91 register long _arg2 __asm__ ("r5") = (long)(arg2); \ 92 register long _arg3 __asm__ ("r6") = (long)(arg3); \ 93 register long _arg4 __asm__ ("r7") = (long)(arg4); \ 94 \ 95 __asm__ volatile ( \ 96 "trapa #31" \ 97 : "=r"(_ret) \ 98 : "r"(_num), "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4) \ 99 : "memory", "cc" \ 100 ); \ 101 _ret; \ 102 }) 103 104 #define __nolibc_syscall5(num, arg1, arg2, arg3, arg4, arg5) \ 105 ({ \ 106 register long _num __asm__ ("r3") = (num); \ 107 register long _ret __asm__ ("r0"); \ 108 register long _arg1 __asm__ ("r4") = (long)(arg1); \ 109 register long _arg2 __asm__ ("r5") = (long)(arg2); \ 110 register long _arg3 __asm__ ("r6") = (long)(arg3); \ 111 register long _arg4 __asm__ ("r7") = (long)(arg4); \ 112 register long _arg5 __asm__ ("r0") = (long)(arg5); \ 113 \ 114 __asm__ volatile ( \ 115 "trapa #31" \ 116 : "=r"(_ret) \ 117 : "r"(_num), "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), \ 118 "r"(_arg5) \ 119 : "memory", "cc" \ 120 ); \ 121 _ret; \ 122 }) 123 124 #define __nolibc_syscall6(num, arg1, arg2, arg3, arg4, arg5, arg6) \ 125 ({ \ 126 register long _num __asm__ ("r3") = (num); \ 127 register long _ret __asm__ ("r0"); \ 128 register long _arg1 __asm__ ("r4") = (long)(arg1); \ 129 register long _arg2 __asm__ ("r5") = (long)(arg2); \ 130 register long _arg3 __asm__ ("r6") = (long)(arg3); \ 131 register long _arg4 __asm__ ("r7") = (long)(arg4); \ 132 register long _arg5 __asm__ ("r0") = (long)(arg5); \ 133 register long _arg6 __asm__ ("r1") = (long)(arg6); \ 134 \ 135 __asm__ volatile ( \ 136 "trapa #31" \ 137 : "=r"(_ret) \ 138 : "r"(_num), "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), \ 139 "r"(_arg5), "r"(_arg6) \ 140 : "memory", "cc" \ 141 ); \ 142 _ret; \ 143 }) 144 145 #ifndef NOLIBC_NO_RUNTIME 146 /* startup code */ 147 void _start_wrapper(void); 148 void __attribute__((weak, noreturn)) __nolibc_entrypoint __nolibc_no_stack_protector _start_wrapper(void) 149 { 150 __asm__ volatile ( 151 ".global _start\n" /* The C function will have a prologue, */ 152 ".type _start, @function\n" /* corrupting "sp" */ 153 ".weak _start\n" 154 "_start:\n" 155 156 "mov sp, r4\n" /* save argc pointer to r4, as arg1 of _start_c */ 157 "bsr _start_c\n" /* transfer to c runtime */ 158 "nop\n" /* delay slot */ 159 160 ".size _start, .-_start\n" 161 ); 162 __nolibc_entrypoint_epilogue(); 163 } 164 #endif /* NOLIBC_NO_RUNTIME */ 165 166 static __attribute__((unused)) 167 ssize_t _sys_pread(int fd, void *buf, size_t count, off_t offset) 168 { 169 return __nolibc_syscall6(__NR_pread64, fd, buf, count, 0, 170 __NOLIBC_LLARGPART(offset, 0), __NOLIBC_LLARGPART(offset, 1)); 171 } 172 #define _sys_pread _sys_pread 173 174 static __attribute__((unused)) 175 ssize_t _sys_pwrite(int fd, const void *buf, size_t count, off_t offset) 176 { 177 return __nolibc_syscall6(__NR_pwrite64, fd, buf, count, 0, 178 __NOLIBC_LLARGPART(offset, 0), __NOLIBC_LLARGPART(offset, 1)); 179 } 180 #define _sys_pwrite _sys_pwrite 181 182 #endif /* _NOLIBC_ARCH_SH_H */ 183