1 /* Copyright (C) 2000-2023 Free Software Foundation, Inc.
2
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public License as
7 published by the Free Software Foundation; either version 2.1 of the
8 License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19 #ifndef _LINUX_MICROBLAZE_SYSDEP_H
20 #define _LINUX_MICROBLAZE_SYSDEP_H 1
21
22 #include <sysdeps/unix/sysdep.h>
23 #include <sysdeps/unix/sysv/linux/sysdep.h>
24 #include <sysdeps/microblaze/sysdep.h>
25
26 /* Defines RTLD_PRIVATE_ERRNO. */
27 #include <dl-sysdep.h>
28
29 #include <tls.h>
30
31 /* In order to get __set_errno() definition in INLINE_SYSCALL. */
32 #ifndef __ASSEMBLER__
33 # include <errno.h>
34 #endif
35
36 /* For Linux we can use the system call table in the header file
37 /usr/include/asm/unistd.h
38 of the kernel. But these symbols do not follow the SYS_* syntax
39 so we have to redefine the `SYS_ify' macro here. */
40 #undef SYS_ify
41 #define SYS_ify(syscall_name) __NR_##syscall_name
42
43 #ifdef __ASSEMBLER__
44
45 /* In microblaze ABI function call arguments are passed in registers
46 r5...r10. The return value is stored in r3 (or r3:r4 register pair).
47 Linux syscall uses the same convention with the addition that the
48 syscall number is passed in r12. To enter the kernel "brki r14,8"
49 instruction is used.
50 None of the abovementioned registers are presumed across function call
51 or syscall.
52 */
53 /* Linux uses a negative return value to indicate syscall errors, unlike
54 most Unices, which use the condition codes' carry flag.
55
56 Since version 2.1 the return value of a system call might be negative
57 even if the call succeeded. E.g., the `lseek' system call might return
58 a large offset. Therefore we must not anymore test for < 0, but test
59 for a real error by making sure the value in %d0 is a real error
60 number. Linus said he will make sure the no syscall returns a value
61 in -1 .. -4095 as a valid result so we can safely test with -4095. */
62
63 /* We don't want the label for the error handler to be visible in the symbol
64 table when we define it here. */
65 # undef SYSCALL_ERROR_LABEL
66 # ifdef PIC
67 # define SYSCALL_ERROR_LABEL 0f
68 # else
69 # define SYSCALL_ERROR_LABEL __syscall_error
70 # endif
71
72 # undef PSEUDO
73 # define PSEUDO(name, syscall_name, args) \
74 .text; \
75 ENTRY (name) \
76 DO_CALL (syscall_name, args); \
77 addik r12,r0,-4095; \
78 cmpu r12,r12,r3; \
79 bgei r12,SYSCALL_ERROR_LABEL;
80
81 # undef PSEUDO_END
82 # define PSEUDO_END(name) \
83 SYSCALL_ERROR_HANDLER; \
84 END (name)
85
86 # undef PSEUDO_NOERRNO
87 # define PSEUDO_NOERRNO(name, syscall_name, args) \
88 .text; \
89 ENTRY (name) \
90 DO_CALL (syscall_name, args);
91
92 # undef PSEUDO_END_NOERRNO
93 # define PSEUDO_END_NOERRNO(name) \
94 END (name)
95
96 /* The function has to return the error code. */
97 # undef PSEUDO_ERRVAL
98 # define PSEUDO_ERRVAL(name, syscall_name, args) \
99 .text; \
100 ENTRY (name) \
101 DO_CALL (syscall_name, args); \
102
103 # undef PSEUDO_END_ERRVAL
104 # define PSEUDO_END_ERRVAL(name) \
105 END (name)
106
107 # define ret_NOERRNO \
108 rtsd r15,8; addk r0,r0,r0;
109
110 # define ret_ERRVAL \
111 rtsd r15,8; rsubk r3,r3,r0;
112
113 # ifdef PIC
114 # define SYSCALL_ERROR_LABEL_DCL 0
115 # if RTLD_PRIVATE_ERRNO
116 # define SYSCALL_ERROR_HANDLER \
117 SYSCALL_ERROR_LABEL_DCL: \
118 mfs r12,rpc; \
119 addik r12,r12,_GLOBAL_OFFSET_TABLE_+8; \
120 lwi r12,r12,rtld_errno@GOT; \
121 rsubk r3,r3,r0; \
122 swi r3,r12,0; \
123 rtsd r15,8; \
124 addik r3,r0,-1;
125 # else /* !RTLD_PRIVATE_ERRNO. */
126 /* Store (-r3) into errno through the GOT. */
127 # if defined _LIBC_REENTRANT
128 # define SYSCALL_ERROR_HANDLER \
129 SYSCALL_ERROR_LABEL_DCL: \
130 addik r1,r1,-16; \
131 swi r15,r1,0; \
132 swi r20,r1,8; \
133 rsubk r3,r3,r0; \
134 swi r3,r1,12; \
135 mfs r20,rpc; \
136 addik r20,r20,_GLOBAL_OFFSET_TABLE_+8; \
137 brlid r15,__errno_location@PLT; \
138 nop; \
139 lwi r4,r1,12; \
140 swi r4,r3,0; \
141 lwi r20,r1,8; \
142 lwi r15,r1,0; \
143 addik r1,r1,16; \
144 rtsd r15,8; \
145 addik r3,r0,-1;
146 # else /* !_LIBC_REENTRANT. */
147 # define SYSCALL_ERROR_HANDLER \
148 SYSCALL_ERROR_LABEL_DCL: \
149 mfs r12,rpc; \
150 addik r12,r12,_GLOBAL_OFFSET_TABLE_+8; \
151 lwi r12,r12,errno@GOT; \
152 rsubk r3,r3,r0; \
153 swi r3,r12,0; \
154 rtsd r15,8; \
155 addik r3,r0,-1;
156 # endif /* _LIBC_REENTRANT. */
157 # endif /* RTLD_PRIVATE_ERRNO. */
158 # else
159 # define SYSCALL_ERROR_HANDLER /* Nothing here; code in sysdep.S is used. */
160 # endif /* PIC. */
161
162 # define DO_CALL(syscall_name, args) \
163 addik r12,r0,SYS_ify (syscall_name); \
164 brki r14,8; \
165 addk r0,r0,r0;
166
167 #else /* not __ASSEMBLER__ */
168
169 /* Define a macro which expands inline into the wrapper code for a system
170 call. This use is for internal calls that do not need to handle errors
171 normally. It will never touch errno. This returns just what the kernel
172 gave back. */
173 # undef INTERNAL_SYSCALL
174 # define INTERNAL_SYSCALL(name, nr, args...) \
175 inline_syscall##nr(SYS_ify(name), args)
176
177 # undef INTERNAL_SYSCALL_NCS
178 # define INTERNAL_SYSCALL_NCS(name, nr, args...) \
179 inline_syscall##nr(name, args)
180
181 # define SYSCALL_CLOBBERS_6 "r11", "r4", "memory"
182 # define SYSCALL_CLOBBERS_5 "r10", SYSCALL_CLOBBERS_6
183 # define SYSCALL_CLOBBERS_4 "r9", SYSCALL_CLOBBERS_5
184 # define SYSCALL_CLOBBERS_3 "r8", SYSCALL_CLOBBERS_4
185 # define SYSCALL_CLOBBERS_2 "r7", SYSCALL_CLOBBERS_3
186 # define SYSCALL_CLOBBERS_1 "r6", SYSCALL_CLOBBERS_2
187 # define SYSCALL_CLOBBERS_0 "r5", SYSCALL_CLOBBERS_1
188
189 # define inline_syscall0(name,dummy) \
190 ({ \
191 register long int __ret __asm__("r3"); \
192 register long int __r12 __asm__("r12") = name; \
193 __asm__ __volatile__( "brki r14,8; nop;" \
194 : "=r"(__ret) \
195 : "r"(__r12) \
196 : SYSCALL_CLOBBERS_0 ); __ret; \
197 })
198
199 # define inline_syscall1(name,arg1) \
200 ({ \
201 long int __arg1 = (long int) (arg1); \
202 register long int __ret __asm__("r3"); \
203 register long int __r12 __asm__("r12") = name; \
204 register long int __r5 __asm__("r5") = __arg1; \
205 __asm__ __volatile__( "brki r14,8; nop;" \
206 : "=r"(__ret) \
207 : "r"(__r5), "r"(__r12) \
208 : SYSCALL_CLOBBERS_1 ); __ret; \
209 })
210
211 # define inline_syscall2(name,arg1,arg2) \
212 ({ \
213 long int __arg1 = (long int) (arg1); \
214 long int __arg2 = (long int) (arg2); \
215 register long int __ret __asm__("r3"); \
216 register long int __r12 __asm__("r12") = name; \
217 register long int __r5 __asm__("r5") = __arg1; \
218 register long int __r6 __asm__("r6") = __arg2; \
219 __asm__ __volatile__( "brki r14,8; nop;" \
220 : "=r"(__ret) \
221 : "r"(__r5), "r"(__r6), "r"(__r12) \
222 : SYSCALL_CLOBBERS_2 ); __ret; \
223 })
224
225
226 # define inline_syscall3(name,arg1,arg2,arg3) \
227 ({ \
228 long int __arg1 = (long int) (arg1); \
229 long int __arg2 = (long int) (arg2); \
230 long int __arg3 = (long int) (arg3); \
231 register long int __ret __asm__("r3"); \
232 register long int __r12 __asm__("r12") = name; \
233 register long int __r5 __asm__("r5") = __arg1; \
234 register long int __r6 __asm__("r6") = __arg2; \
235 register long int __r7 __asm__("r7") = __arg3; \
236 __asm__ __volatile__( "brki r14,8; nop;" \
237 : "=r"(__ret) \
238 : "r"(__r5), "r"(__r6), "r"(__r7), "r"(__r12) \
239 : SYSCALL_CLOBBERS_3 ); __ret; \
240 })
241
242
243 # define inline_syscall4(name,arg1,arg2,arg3,arg4) \
244 ({ \
245 long int __arg1 = (long int) (arg1); \
246 long int __arg2 = (long int) (arg2); \
247 long int __arg3 = (long int) (arg3); \
248 long int __arg4 = (long int) (arg4); \
249 register long int __ret __asm__("r3"); \
250 register long int __r12 __asm__("r12") = name; \
251 register long int __r5 __asm__("r5") = __arg1; \
252 register long int __r6 __asm__("r6") = __arg2; \
253 register long int __r7 __asm__("r7") = __arg3; \
254 register long int __r8 __asm__("r8") = __arg4; \
255 __asm__ __volatile__( "brki r14,8; nop;" \
256 : "=r"(__ret) \
257 : "r"(__r5), "r"(__r6), "r"(__r7), "r"(__r8),"r"(__r12) \
258 : SYSCALL_CLOBBERS_4 ); __ret; \
259 })
260
261
262 # define inline_syscall5(name,arg1,arg2,arg3,arg4,arg5) \
263 ({ \
264 long int __arg1 = (long int) (arg1); \
265 long int __arg2 = (long int) (arg2); \
266 long int __arg3 = (long int) (arg3); \
267 long int __arg4 = (long int) (arg4); \
268 long int __arg5 = (long int) (arg5); \
269 register long int __ret __asm__("r3"); \
270 register long int __r12 __asm__("r12") = name; \
271 register long int __r5 __asm__("r5") = __arg1; \
272 register long int __r6 __asm__("r6") = __arg2; \
273 register long int __r7 __asm__("r7") = __arg3; \
274 register long int __r8 __asm__("r8") = __arg4; \
275 register long int __r9 __asm__("r9") = __arg5; \
276 __asm__ __volatile__( "brki r14,8; nop;" \
277 : "=r"(__ret) \
278 : "r"(__r5), "r"(__r6), "r"(__r7), "r"(__r8),"r"(__r9), "r"(__r12) \
279 : SYSCALL_CLOBBERS_5 ); __ret; \
280 })
281
282
283 # define inline_syscall6(name,arg1,arg2,arg3,arg4,arg5,arg6) \
284 ({ \
285 long int __arg1 = (long int) (arg1); \
286 long int __arg2 = (long int) (arg2); \
287 long int __arg3 = (long int) (arg3); \
288 long int __arg4 = (long int) (arg4); \
289 long int __arg5 = (long int) (arg5); \
290 long int __arg6 = (long int) (arg6); \
291 register long int __ret __asm__("r3"); \
292 register long int __r12 __asm__("r12") = name; \
293 register long int __r5 __asm__("r5") = __arg1; \
294 register long int __r6 __asm__("r6") = __arg2; \
295 register long int __r7 __asm__("r7") = __arg3; \
296 register long int __r8 __asm__("r8") = __arg4; \
297 register long int __r9 __asm__("r9") = __arg5; \
298 register long int __r10 __asm__("r10") = __arg6; \
299 __asm__ __volatile__( "brki r14,8; nop;" \
300 : "=r"(__ret) \
301 : "r"(__r5), "r"(__r6), "r"(__r7), "r"(__r8),"r"(__r9), "r"(__r10), \
302 "r"(__r12) \
303 : SYSCALL_CLOBBERS_6 ); __ret; \
304 })
305
306
307 #undef HAVE_INTERNAL_BRK_ADDR_SYMBOL
308 #define HAVE_INTERNAL_BRK_ADDR_SYMBOL 1
309
310 #endif /* not __ASSEMBLER__ */
311
312 #endif /* _LINUX_MICROBLAZE_SYSDEP_H */