1 /* SPDX-License-Identifier: LGPL-2.1 OR MIT */
3 * AARCH64 specific definitions for NOLIBC
4 * Copyright (C) 2017-2022 Willy Tarreau <w@1wt.eu>
7 #ifndef _NOLIBC_ARCH_AARCH64_H
8 #define _NOLIBC_ARCH_AARCH64_H
10 /* O_* macros for fcntl/open are architecture-specific */
16 #define O_NOCTTY 0x100
18 #define O_APPEND 0x400
19 #define O_NONBLOCK 0x800
20 #define O_DIRECTORY 0x4000
22 /* The struct returned by the newfstatat() syscall. Differs slightly from the
23 * x86_64's stat one by field ordering, so be careful.
25 struct sys_stat_struct {
29 unsigned int st_nlink;
33 unsigned long st_rdev;
41 unsigned long st_atime_nsec;
44 unsigned long st_mtime_nsec;
46 unsigned long st_ctime_nsec;
47 unsigned int __unused[2];
50 /* Syscalls for AARCH64 :
51 * - registers are 64-bit
52 * - stack is 16-byte aligned
53 * - syscall number is passed in x8
54 * - arguments are in x0, x1, x2, x3, x4, x5
55 * - the system call is performed by calling svc 0
56 * - syscall return comes in x0.
57 * - the arguments are cast to long and assigned into the target registers
58 * which are then simply passed as registers to the asm code, so that we
59 * don't have to experience issues with register constraints.
61 * On aarch64, select() is not implemented so we have to use pselect6().
63 #define __ARCH_WANT_SYS_PSELECT6
65 #define my_syscall0(num) \
67 register long _num __asm__ ("x8") = (num); \
68 register long _arg1 __asm__ ("x0"); \
79 #define my_syscall1(num, arg1) \
81 register long _num __asm__ ("x8") = (num); \
82 register long _arg1 __asm__ ("x0") = (long)(arg1); \
94 #define my_syscall2(num, arg1, arg2) \
96 register long _num __asm__ ("x8") = (num); \
97 register long _arg1 __asm__ ("x0") = (long)(arg1); \
98 register long _arg2 __asm__ ("x1") = (long)(arg2); \
103 : "r"(_arg1), "r"(_arg2), \
110 #define my_syscall3(num, arg1, arg2, arg3) \
112 register long _num __asm__ ("x8") = (num); \
113 register long _arg1 __asm__ ("x0") = (long)(arg1); \
114 register long _arg2 __asm__ ("x1") = (long)(arg2); \
115 register long _arg3 __asm__ ("x2") = (long)(arg3); \
120 : "r"(_arg1), "r"(_arg2), "r"(_arg3), \
127 #define my_syscall4(num, arg1, arg2, arg3, arg4) \
129 register long _num __asm__ ("x8") = (num); \
130 register long _arg1 __asm__ ("x0") = (long)(arg1); \
131 register long _arg2 __asm__ ("x1") = (long)(arg2); \
132 register long _arg3 __asm__ ("x2") = (long)(arg3); \
133 register long _arg4 __asm__ ("x3") = (long)(arg4); \
138 : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), \
145 #define my_syscall5(num, arg1, arg2, arg3, arg4, arg5) \
147 register long _num __asm__ ("x8") = (num); \
148 register long _arg1 __asm__ ("x0") = (long)(arg1); \
149 register long _arg2 __asm__ ("x1") = (long)(arg2); \
150 register long _arg3 __asm__ ("x2") = (long)(arg3); \
151 register long _arg4 __asm__ ("x3") = (long)(arg4); \
152 register long _arg5 __asm__ ("x4") = (long)(arg5); \
157 : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \
164 #define my_syscall6(num, arg1, arg2, arg3, arg4, arg5, arg6) \
166 register long _num __asm__ ("x8") = (num); \
167 register long _arg1 __asm__ ("x0") = (long)(arg1); \
168 register long _arg2 __asm__ ("x1") = (long)(arg2); \
169 register long _arg3 __asm__ ("x2") = (long)(arg3); \
170 register long _arg4 __asm__ ("x3") = (long)(arg4); \
171 register long _arg5 __asm__ ("x4") = (long)(arg5); \
172 register long _arg6 __asm__ ("x5") = (long)(arg6); \
177 : "r"(_arg1), "r"(_arg2), "r"(_arg3), "r"(_arg4), "r"(_arg5), \
178 "r"(_arg6), "r"(_num) \
185 __asm__ (".section .text\n"
188 "ldr x0, [sp]\n" // argc (x0) was in the stack
189 "add x1, sp, 8\n" // argv (x1) = sp
190 "lsl x2, x0, 3\n" // envp (x2) = 8*argc ...
191 "add x2, x2, 8\n" // + 8 (skip null)
192 "add x2, x2, x1\n" // + argv
193 "and sp, x1, -16\n" // sp must be 16-byte aligned in the callee
194 "bl main\n" // main() returns the status code, we'll exit with it.
195 "mov x8, 93\n" // NR_exit == 93
199 #endif // _NOLIBC_ARCH_AARCH64_H