1 /*
2 * m68k/ColdFire Semihosting syscall interface
3 *
4 * Copyright (c) 2005-2007 CodeSourcery.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, see <http://www.gnu.org/licenses/>.
18 */
19
20 #include "qemu/osdep.h"
21
22 #include "cpu.h"
23 #if defined(CONFIG_USER_ONLY)
24 #include "qemu.h"
25 #define SEMIHOSTING_HEAP_SIZE (128 * 1024 * 1024)
26 #else
27 #include "exec/gdbstub.h"
28 #include "exec/softmmu-semi.h"
29 #endif
30 #include "qemu/log.h"
31
32 #define HOSTED_EXIT 0
33 #define HOSTED_INIT_SIM 1
34 #define HOSTED_OPEN 2
35 #define HOSTED_CLOSE 3
36 #define HOSTED_READ 4
37 #define HOSTED_WRITE 5
38 #define HOSTED_LSEEK 6
39 #define HOSTED_RENAME 7
40 #define HOSTED_UNLINK 8
41 #define HOSTED_STAT 9
42 #define HOSTED_FSTAT 10
43 #define HOSTED_GETTIMEOFDAY 11
44 #define HOSTED_ISATTY 12
45 #define HOSTED_SYSTEM 13
46
47 typedef uint32_t gdb_mode_t;
48 typedef uint32_t gdb_time_t;
49
50 struct m68k_gdb_stat {
51 uint32_t gdb_st_dev; /* device */
52 uint32_t gdb_st_ino; /* inode */
53 gdb_mode_t gdb_st_mode; /* protection */
54 uint32_t gdb_st_nlink; /* number of hard links */
55 uint32_t gdb_st_uid; /* user ID of owner */
56 uint32_t gdb_st_gid; /* group ID of owner */
57 uint32_t gdb_st_rdev; /* device type (if inode device) */
58 uint64_t gdb_st_size; /* total size, in bytes */
59 uint64_t gdb_st_blksize; /* blocksize for filesystem I/O */
60 uint64_t gdb_st_blocks; /* number of blocks allocated */
61 gdb_time_t gdb_st_atime; /* time of last access */
62 gdb_time_t gdb_st_mtime; /* time of last modification */
63 gdb_time_t gdb_st_ctime; /* time of last change */
64 } QEMU_PACKED;
65
66 struct gdb_timeval {
67 gdb_time_t tv_sec; /* second */
68 uint64_t tv_usec; /* microsecond */
69 } QEMU_PACKED;
70
71 #define GDB_O_RDONLY 0x0
72 #define GDB_O_WRONLY 0x1
73 #define GDB_O_RDWR 0x2
74 #define GDB_O_APPEND 0x8
75 #define GDB_O_CREAT 0x200
76 #define GDB_O_TRUNC 0x400
77 #define GDB_O_EXCL 0x800
78
translate_openflags(int flags)79 static int translate_openflags(int flags)
80 {
81 int hf;
82
83 if (flags & GDB_O_WRONLY)
84 hf = O_WRONLY;
85 else if (flags & GDB_O_RDWR)
86 hf = O_RDWR;
87 else
88 hf = O_RDONLY;
89
90 if (flags & GDB_O_APPEND) hf |= O_APPEND;
91 if (flags & GDB_O_CREAT) hf |= O_CREAT;
92 if (flags & GDB_O_TRUNC) hf |= O_TRUNC;
93 if (flags & GDB_O_EXCL) hf |= O_EXCL;
94
95 return hf;
96 }
97
translate_stat(CPUM68KState * env,target_ulong addr,struct stat * s)98 static void translate_stat(CPUM68KState *env, target_ulong addr, struct stat *s)
99 {
100 struct m68k_gdb_stat *p;
101
102 if (!(p = lock_user(VERIFY_WRITE, addr, sizeof(struct m68k_gdb_stat), 0)))
103 /* FIXME - should this return an error code? */
104 return;
105 p->gdb_st_dev = cpu_to_be32(s->st_dev);
106 p->gdb_st_ino = cpu_to_be32(s->st_ino);
107 p->gdb_st_mode = cpu_to_be32(s->st_mode);
108 p->gdb_st_nlink = cpu_to_be32(s->st_nlink);
109 p->gdb_st_uid = cpu_to_be32(s->st_uid);
110 p->gdb_st_gid = cpu_to_be32(s->st_gid);
111 p->gdb_st_rdev = cpu_to_be32(s->st_rdev);
112 p->gdb_st_size = cpu_to_be64(s->st_size);
113 #ifdef _WIN32
114 /* Windows stat is missing some fields. */
115 p->gdb_st_blksize = 0;
116 p->gdb_st_blocks = 0;
117 #else
118 p->gdb_st_blksize = cpu_to_be64(s->st_blksize);
119 p->gdb_st_blocks = cpu_to_be64(s->st_blocks);
120 #endif
121 p->gdb_st_atime = cpu_to_be32(s->st_atime);
122 p->gdb_st_mtime = cpu_to_be32(s->st_mtime);
123 p->gdb_st_ctime = cpu_to_be32(s->st_ctime);
124 unlock_user(p, addr, sizeof(struct m68k_gdb_stat));
125 }
126
m68k_semi_return_u32(CPUM68KState * env,uint32_t ret,uint32_t err)127 static void m68k_semi_return_u32(CPUM68KState *env, uint32_t ret, uint32_t err)
128 {
129 target_ulong args = env->dregs[1];
130 if (put_user_u32(ret, args) ||
131 put_user_u32(err, args + 4)) {
132 /*
133 * The m68k semihosting ABI does not provide any way to report this
134 * error to the guest, so the best we can do is log it in qemu.
135 * It is always a guest error not to pass us a valid argument block.
136 */
137 qemu_log_mask(LOG_GUEST_ERROR, "m68k-semihosting: return value "
138 "discarded because argument block not writable\n");
139 }
140 }
141
m68k_semi_return_u64(CPUM68KState * env,uint64_t ret,uint32_t err)142 static void m68k_semi_return_u64(CPUM68KState *env, uint64_t ret, uint32_t err)
143 {
144 target_ulong args = env->dregs[1];
145 if (put_user_u32(ret >> 32, args) ||
146 put_user_u32(ret, args + 4) ||
147 put_user_u32(err, args + 8)) {
148 /* No way to report this via m68k semihosting ABI; just log it */
149 qemu_log_mask(LOG_GUEST_ERROR, "m68k-semihosting: return value "
150 "discarded because argument block not writable\n");
151 }
152 }
153
154 static int m68k_semi_is_fseek;
155
m68k_semi_cb(CPUState * cs,target_ulong ret,target_ulong err)156 static void m68k_semi_cb(CPUState *cs, target_ulong ret, target_ulong err)
157 {
158 M68kCPU *cpu = M68K_CPU(cs);
159 CPUM68KState *env = &cpu->env;
160
161 if (m68k_semi_is_fseek) {
162 /*
163 * FIXME: We've already lost the high bits of the fseek
164 * return value.
165 */
166 m68k_semi_return_u64(env, ret, err);
167 m68k_semi_is_fseek = 0;
168 } else {
169 m68k_semi_return_u32(env, ret, err);
170 }
171 }
172
173 /*
174 * Read the input value from the argument block; fail the semihosting
175 * call if the memory read fails.
176 */
177 #define GET_ARG(n) do { \
178 if (get_user_ual(arg ## n, args + (n) * 4)) { \
179 result = -1; \
180 errno = EFAULT; \
181 goto failed; \
182 } \
183 } while (0)
184
do_m68k_semihosting(CPUM68KState * env,int nr)185 void do_m68k_semihosting(CPUM68KState *env, int nr)
186 {
187 uint32_t args;
188 target_ulong arg0, arg1, arg2, arg3;
189 void *p;
190 void *q;
191 uint32_t len;
192 uint32_t result;
193
194 args = env->dregs[1];
195 switch (nr) {
196 case HOSTED_EXIT:
197 gdb_exit(env, env->dregs[0]);
198 exit(env->dregs[0]);
199 case HOSTED_OPEN:
200 GET_ARG(0);
201 GET_ARG(1);
202 GET_ARG(2);
203 GET_ARG(3);
204 if (use_gdb_syscalls()) {
205 gdb_do_syscall(m68k_semi_cb, "open,%s,%x,%x", arg0, (int)arg1,
206 arg2, arg3);
207 return;
208 } else {
209 p = lock_user_string(arg0);
210 if (!p) {
211 /* FIXME - check error code? */
212 result = -1;
213 } else {
214 result = open(p, translate_openflags(arg2), arg3);
215 unlock_user(p, arg0, 0);
216 }
217 }
218 break;
219 case HOSTED_CLOSE:
220 {
221 /* Ignore attempts to close stdin/out/err. */
222 GET_ARG(0);
223 int fd = arg0;
224 if (fd > 2) {
225 if (use_gdb_syscalls()) {
226 gdb_do_syscall(m68k_semi_cb, "close,%x", arg0);
227 return;
228 } else {
229 result = close(fd);
230 }
231 } else {
232 result = 0;
233 }
234 break;
235 }
236 case HOSTED_READ:
237 GET_ARG(0);
238 GET_ARG(1);
239 GET_ARG(2);
240 len = arg2;
241 if (use_gdb_syscalls()) {
242 gdb_do_syscall(m68k_semi_cb, "read,%x,%x,%x",
243 arg0, arg1, len);
244 return;
245 } else {
246 p = lock_user(VERIFY_WRITE, arg1, len, 0);
247 if (!p) {
248 /* FIXME - check error code? */
249 result = -1;
250 } else {
251 result = read(arg0, p, len);
252 unlock_user(p, arg1, len);
253 }
254 }
255 break;
256 case HOSTED_WRITE:
257 GET_ARG(0);
258 GET_ARG(1);
259 GET_ARG(2);
260 len = arg2;
261 if (use_gdb_syscalls()) {
262 gdb_do_syscall(m68k_semi_cb, "write,%x,%x,%x",
263 arg0, arg1, len);
264 return;
265 } else {
266 p = lock_user(VERIFY_READ, arg1, len, 1);
267 if (!p) {
268 /* FIXME - check error code? */
269 result = -1;
270 } else {
271 result = write(arg0, p, len);
272 unlock_user(p, arg0, 0);
273 }
274 }
275 break;
276 case HOSTED_LSEEK:
277 {
278 uint64_t off;
279 GET_ARG(0);
280 GET_ARG(1);
281 GET_ARG(2);
282 GET_ARG(3);
283 off = (uint32_t)arg2 | ((uint64_t)arg1 << 32);
284 if (use_gdb_syscalls()) {
285 m68k_semi_is_fseek = 1;
286 gdb_do_syscall(m68k_semi_cb, "fseek,%x,%lx,%x",
287 arg0, off, arg3);
288 } else {
289 off = lseek(arg0, off, arg3);
290 m68k_semi_return_u64(env, off, errno);
291 }
292 return;
293 }
294 case HOSTED_RENAME:
295 GET_ARG(0);
296 GET_ARG(1);
297 GET_ARG(2);
298 GET_ARG(3);
299 if (use_gdb_syscalls()) {
300 gdb_do_syscall(m68k_semi_cb, "rename,%s,%s",
301 arg0, (int)arg1, arg2, (int)arg3);
302 return;
303 } else {
304 p = lock_user_string(arg0);
305 q = lock_user_string(arg2);
306 if (!p || !q) {
307 /* FIXME - check error code? */
308 result = -1;
309 } else {
310 result = rename(p, q);
311 }
312 unlock_user(p, arg0, 0);
313 unlock_user(q, arg2, 0);
314 }
315 break;
316 case HOSTED_UNLINK:
317 GET_ARG(0);
318 GET_ARG(1);
319 if (use_gdb_syscalls()) {
320 gdb_do_syscall(m68k_semi_cb, "unlink,%s",
321 arg0, (int)arg1);
322 return;
323 } else {
324 p = lock_user_string(arg0);
325 if (!p) {
326 /* FIXME - check error code? */
327 result = -1;
328 } else {
329 result = unlink(p);
330 unlock_user(p, arg0, 0);
331 }
332 }
333 break;
334 case HOSTED_STAT:
335 GET_ARG(0);
336 GET_ARG(1);
337 GET_ARG(2);
338 if (use_gdb_syscalls()) {
339 gdb_do_syscall(m68k_semi_cb, "stat,%s,%x",
340 arg0, (int)arg1, arg2);
341 return;
342 } else {
343 struct stat s;
344 p = lock_user_string(arg0);
345 if (!p) {
346 /* FIXME - check error code? */
347 result = -1;
348 } else {
349 result = stat(p, &s);
350 unlock_user(p, arg0, 0);
351 }
352 if (result == 0) {
353 translate_stat(env, arg2, &s);
354 }
355 }
356 break;
357 case HOSTED_FSTAT:
358 GET_ARG(0);
359 GET_ARG(1);
360 if (use_gdb_syscalls()) {
361 gdb_do_syscall(m68k_semi_cb, "fstat,%x,%x",
362 arg0, arg1);
363 return;
364 } else {
365 struct stat s;
366 result = fstat(arg0, &s);
367 if (result == 0) {
368 translate_stat(env, arg1, &s);
369 }
370 }
371 break;
372 case HOSTED_GETTIMEOFDAY:
373 GET_ARG(0);
374 GET_ARG(1);
375 if (use_gdb_syscalls()) {
376 gdb_do_syscall(m68k_semi_cb, "gettimeofday,%x,%x",
377 arg0, arg1);
378 return;
379 } else {
380 qemu_timeval tv;
381 struct gdb_timeval *p;
382 result = qemu_gettimeofday(&tv);
383 if (result != 0) {
384 if (!(p = lock_user(VERIFY_WRITE,
385 arg0, sizeof(struct gdb_timeval), 0))) {
386 /* FIXME - check error code? */
387 result = -1;
388 } else {
389 p->tv_sec = cpu_to_be32(tv.tv_sec);
390 p->tv_usec = cpu_to_be64(tv.tv_usec);
391 unlock_user(p, arg0, sizeof(struct gdb_timeval));
392 }
393 }
394 }
395 break;
396 case HOSTED_ISATTY:
397 GET_ARG(0);
398 if (use_gdb_syscalls()) {
399 gdb_do_syscall(m68k_semi_cb, "isatty,%x", arg0);
400 return;
401 } else {
402 result = isatty(arg0);
403 }
404 break;
405 case HOSTED_SYSTEM:
406 GET_ARG(0);
407 GET_ARG(1);
408 if (use_gdb_syscalls()) {
409 gdb_do_syscall(m68k_semi_cb, "system,%s",
410 arg0, (int)arg1);
411 return;
412 } else {
413 p = lock_user_string(arg0);
414 if (!p) {
415 /* FIXME - check error code? */
416 result = -1;
417 } else {
418 result = system(p);
419 unlock_user(p, arg0, 0);
420 }
421 }
422 break;
423 case HOSTED_INIT_SIM:
424 #if defined(CONFIG_USER_ONLY)
425 {
426 CPUState *cs = env_cpu(env);
427 TaskState *ts = cs->opaque;
428 /* Allocate the heap using sbrk. */
429 if (!ts->heap_limit) {
430 abi_ulong ret;
431 uint32_t size;
432 uint32_t base;
433
434 base = do_brk(0);
435 size = SEMIHOSTING_HEAP_SIZE;
436 /* Try a big heap, and reduce the size if that fails. */
437 for (;;) {
438 ret = do_brk(base + size);
439 if (ret >= (base + size)) {
440 break;
441 }
442 size >>= 1;
443 }
444 ts->heap_limit = base + size;
445 }
446 /*
447 * This call may happen before we have writable memory, so return
448 * values directly in registers.
449 */
450 env->dregs[1] = ts->heap_limit;
451 env->aregs[7] = ts->stack_base;
452 }
453 #else
454 /*
455 * FIXME: This is wrong for boards where RAM does not start at
456 * address zero.
457 */
458 env->dregs[1] = ram_size;
459 env->aregs[7] = ram_size;
460 #endif
461 return;
462 default:
463 cpu_abort(env_cpu(env), "Unsupported semihosting syscall %d\n", nr);
464 result = 0;
465 }
466 failed:
467 m68k_semi_return_u32(env, result, errno);
468 }
469