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 #include "exec/gdbstub.h"
24 #if defined(CONFIG_USER_ONLY)
25 #include "qemu.h"
26 #define SEMIHOSTING_HEAP_SIZE (128 * 1024 * 1024)
27 #else
28 #include "exec/softmmu-semi.h"
29 #include "hw/boards.h"
30 #endif
31 #include "qemu/log.h"
32
33 #define HOSTED_EXIT 0
34 #define HOSTED_INIT_SIM 1
35 #define HOSTED_OPEN 2
36 #define HOSTED_CLOSE 3
37 #define HOSTED_READ 4
38 #define HOSTED_WRITE 5
39 #define HOSTED_LSEEK 6
40 #define HOSTED_RENAME 7
41 #define HOSTED_UNLINK 8
42 #define HOSTED_STAT 9
43 #define HOSTED_FSTAT 10
44 #define HOSTED_GETTIMEOFDAY 11
45 #define HOSTED_ISATTY 12
46 #define HOSTED_SYSTEM 13
47
48 typedef uint32_t gdb_mode_t;
49 typedef uint32_t gdb_time_t;
50
51 struct m68k_gdb_stat {
52 uint32_t gdb_st_dev; /* device */
53 uint32_t gdb_st_ino; /* inode */
54 gdb_mode_t gdb_st_mode; /* protection */
55 uint32_t gdb_st_nlink; /* number of hard links */
56 uint32_t gdb_st_uid; /* user ID of owner */
57 uint32_t gdb_st_gid; /* group ID of owner */
58 uint32_t gdb_st_rdev; /* device type (if inode device) */
59 uint64_t gdb_st_size; /* total size, in bytes */
60 uint64_t gdb_st_blksize; /* blocksize for filesystem I/O */
61 uint64_t gdb_st_blocks; /* number of blocks allocated */
62 gdb_time_t gdb_st_atime; /* time of last access */
63 gdb_time_t gdb_st_mtime; /* time of last modification */
64 gdb_time_t gdb_st_ctime; /* time of last change */
65 } QEMU_PACKED;
66
67 struct gdb_timeval {
68 gdb_time_t tv_sec; /* second */
69 uint64_t tv_usec; /* microsecond */
70 } QEMU_PACKED;
71
72 #define GDB_O_RDONLY 0x0
73 #define GDB_O_WRONLY 0x1
74 #define GDB_O_RDWR 0x2
75 #define GDB_O_APPEND 0x8
76 #define GDB_O_CREAT 0x200
77 #define GDB_O_TRUNC 0x400
78 #define GDB_O_EXCL 0x800
79
translate_openflags(int flags)80 static int translate_openflags(int flags)
81 {
82 int hf;
83
84 if (flags & GDB_O_WRONLY)
85 hf = O_WRONLY;
86 else if (flags & GDB_O_RDWR)
87 hf = O_RDWR;
88 else
89 hf = O_RDONLY;
90
91 if (flags & GDB_O_APPEND) hf |= O_APPEND;
92 if (flags & GDB_O_CREAT) hf |= O_CREAT;
93 if (flags & GDB_O_TRUNC) hf |= O_TRUNC;
94 if (flags & GDB_O_EXCL) hf |= O_EXCL;
95
96 return hf;
97 }
98
translate_stat(CPUM68KState * env,target_ulong addr,struct stat * s)99 static void translate_stat(CPUM68KState *env, target_ulong addr, struct stat *s)
100 {
101 struct m68k_gdb_stat *p;
102
103 if (!(p = lock_user(VERIFY_WRITE, addr, sizeof(struct m68k_gdb_stat), 0)))
104 /* FIXME - should this return an error code? */
105 return;
106 p->gdb_st_dev = cpu_to_be32(s->st_dev);
107 p->gdb_st_ino = cpu_to_be32(s->st_ino);
108 p->gdb_st_mode = cpu_to_be32(s->st_mode);
109 p->gdb_st_nlink = cpu_to_be32(s->st_nlink);
110 p->gdb_st_uid = cpu_to_be32(s->st_uid);
111 p->gdb_st_gid = cpu_to_be32(s->st_gid);
112 p->gdb_st_rdev = cpu_to_be32(s->st_rdev);
113 p->gdb_st_size = cpu_to_be64(s->st_size);
114 #ifdef _WIN32
115 /* Windows stat is missing some fields. */
116 p->gdb_st_blksize = 0;
117 p->gdb_st_blocks = 0;
118 #else
119 p->gdb_st_blksize = cpu_to_be64(s->st_blksize);
120 p->gdb_st_blocks = cpu_to_be64(s->st_blocks);
121 #endif
122 p->gdb_st_atime = cpu_to_be32(s->st_atime);
123 p->gdb_st_mtime = cpu_to_be32(s->st_mtime);
124 p->gdb_st_ctime = cpu_to_be32(s->st_ctime);
125 unlock_user(p, addr, sizeof(struct m68k_gdb_stat));
126 }
127
m68k_semi_return_u32(CPUM68KState * env,uint32_t ret,uint32_t err)128 static void m68k_semi_return_u32(CPUM68KState *env, uint32_t ret, uint32_t err)
129 {
130 target_ulong args = env->dregs[1];
131 if (put_user_u32(ret, args) ||
132 put_user_u32(err, args + 4)) {
133 /*
134 * The m68k semihosting ABI does not provide any way to report this
135 * error to the guest, so the best we can do is log it in qemu.
136 * It is always a guest error not to pass us a valid argument block.
137 */
138 qemu_log_mask(LOG_GUEST_ERROR, "m68k-semihosting: return value "
139 "discarded because argument block not writable\n");
140 }
141 }
142
m68k_semi_return_u64(CPUM68KState * env,uint64_t ret,uint32_t err)143 static void m68k_semi_return_u64(CPUM68KState *env, uint64_t ret, uint32_t err)
144 {
145 target_ulong args = env->dregs[1];
146 if (put_user_u32(ret >> 32, args) ||
147 put_user_u32(ret, args + 4) ||
148 put_user_u32(err, args + 8)) {
149 /* No way to report this via m68k semihosting ABI; just log it */
150 qemu_log_mask(LOG_GUEST_ERROR, "m68k-semihosting: return value "
151 "discarded because argument block not writable\n");
152 }
153 }
154
155 static int m68k_semi_is_fseek;
156
m68k_semi_cb(CPUState * cs,target_ulong ret,target_ulong err)157 static void m68k_semi_cb(CPUState *cs, target_ulong ret, target_ulong err)
158 {
159 M68kCPU *cpu = M68K_CPU(cs);
160 CPUM68KState *env = &cpu->env;
161
162 if (m68k_semi_is_fseek) {
163 /*
164 * FIXME: We've already lost the high bits of the fseek
165 * return value.
166 */
167 m68k_semi_return_u64(env, ret, err);
168 m68k_semi_is_fseek = 0;
169 } else {
170 m68k_semi_return_u32(env, ret, err);
171 }
172 }
173
174 /*
175 * Read the input value from the argument block; fail the semihosting
176 * call if the memory read fails.
177 */
178 #define GET_ARG(n) do { \
179 if (get_user_ual(arg ## n, args + (n) * 4)) { \
180 result = -1; \
181 errno = EFAULT; \
182 goto failed; \
183 } \
184 } while (0)
185
do_m68k_semihosting(CPUM68KState * env,int nr)186 void do_m68k_semihosting(CPUM68KState *env, int nr)
187 {
188 uint32_t args;
189 target_ulong arg0, arg1, arg2, arg3;
190 void *p;
191 void *q;
192 uint32_t len;
193 uint32_t result;
194
195 args = env->dregs[1];
196 switch (nr) {
197 case HOSTED_EXIT:
198 gdb_exit(env->dregs[0]);
199 exit(env->dregs[0]);
200 case HOSTED_OPEN:
201 GET_ARG(0);
202 GET_ARG(1);
203 GET_ARG(2);
204 GET_ARG(3);
205 if (use_gdb_syscalls()) {
206 gdb_do_syscall(m68k_semi_cb, "open,%s,%x,%x", arg0, (int)arg1,
207 arg2, arg3);
208 return;
209 } else {
210 p = lock_user_string(arg0);
211 if (!p) {
212 /* FIXME - check error code? */
213 result = -1;
214 } else {
215 result = open(p, translate_openflags(arg2), arg3);
216 unlock_user(p, arg0, 0);
217 }
218 }
219 break;
220 case HOSTED_CLOSE:
221 {
222 /* Ignore attempts to close stdin/out/err. */
223 GET_ARG(0);
224 int fd = arg0;
225 if (fd > 2) {
226 if (use_gdb_syscalls()) {
227 gdb_do_syscall(m68k_semi_cb, "close,%x", arg0);
228 return;
229 } else {
230 result = close(fd);
231 }
232 } else {
233 result = 0;
234 }
235 break;
236 }
237 case HOSTED_READ:
238 GET_ARG(0);
239 GET_ARG(1);
240 GET_ARG(2);
241 len = arg2;
242 if (use_gdb_syscalls()) {
243 gdb_do_syscall(m68k_semi_cb, "read,%x,%x,%x",
244 arg0, arg1, len);
245 return;
246 } else {
247 p = lock_user(VERIFY_WRITE, arg1, len, 0);
248 if (!p) {
249 /* FIXME - check error code? */
250 result = -1;
251 } else {
252 result = read(arg0, p, len);
253 unlock_user(p, arg1, len);
254 }
255 }
256 break;
257 case HOSTED_WRITE:
258 GET_ARG(0);
259 GET_ARG(1);
260 GET_ARG(2);
261 len = arg2;
262 if (use_gdb_syscalls()) {
263 gdb_do_syscall(m68k_semi_cb, "write,%x,%x,%x",
264 arg0, arg1, len);
265 return;
266 } else {
267 p = lock_user(VERIFY_READ, arg1, len, 1);
268 if (!p) {
269 /* FIXME - check error code? */
270 result = -1;
271 } else {
272 result = write(arg0, p, len);
273 unlock_user(p, arg0, 0);
274 }
275 }
276 break;
277 case HOSTED_LSEEK:
278 {
279 uint64_t off;
280 GET_ARG(0);
281 GET_ARG(1);
282 GET_ARG(2);
283 GET_ARG(3);
284 off = (uint32_t)arg2 | ((uint64_t)arg1 << 32);
285 if (use_gdb_syscalls()) {
286 m68k_semi_is_fseek = 1;
287 gdb_do_syscall(m68k_semi_cb, "fseek,%x,%lx,%x",
288 arg0, off, arg3);
289 } else {
290 off = lseek(arg0, off, arg3);
291 m68k_semi_return_u64(env, off, errno);
292 }
293 return;
294 }
295 case HOSTED_RENAME:
296 GET_ARG(0);
297 GET_ARG(1);
298 GET_ARG(2);
299 GET_ARG(3);
300 if (use_gdb_syscalls()) {
301 gdb_do_syscall(m68k_semi_cb, "rename,%s,%s",
302 arg0, (int)arg1, arg2, (int)arg3);
303 return;
304 } else {
305 p = lock_user_string(arg0);
306 q = lock_user_string(arg2);
307 if (!p || !q) {
308 /* FIXME - check error code? */
309 result = -1;
310 } else {
311 result = rename(p, q);
312 }
313 unlock_user(p, arg0, 0);
314 unlock_user(q, arg2, 0);
315 }
316 break;
317 case HOSTED_UNLINK:
318 GET_ARG(0);
319 GET_ARG(1);
320 if (use_gdb_syscalls()) {
321 gdb_do_syscall(m68k_semi_cb, "unlink,%s",
322 arg0, (int)arg1);
323 return;
324 } else {
325 p = lock_user_string(arg0);
326 if (!p) {
327 /* FIXME - check error code? */
328 result = -1;
329 } else {
330 result = unlink(p);
331 unlock_user(p, arg0, 0);
332 }
333 }
334 break;
335 case HOSTED_STAT:
336 GET_ARG(0);
337 GET_ARG(1);
338 GET_ARG(2);
339 if (use_gdb_syscalls()) {
340 gdb_do_syscall(m68k_semi_cb, "stat,%s,%x",
341 arg0, (int)arg1, arg2);
342 return;
343 } else {
344 struct stat s;
345 p = lock_user_string(arg0);
346 if (!p) {
347 /* FIXME - check error code? */
348 result = -1;
349 } else {
350 result = stat(p, &s);
351 unlock_user(p, arg0, 0);
352 }
353 if (result == 0) {
354 translate_stat(env, arg2, &s);
355 }
356 }
357 break;
358 case HOSTED_FSTAT:
359 GET_ARG(0);
360 GET_ARG(1);
361 if (use_gdb_syscalls()) {
362 gdb_do_syscall(m68k_semi_cb, "fstat,%x,%x",
363 arg0, arg1);
364 return;
365 } else {
366 struct stat s;
367 result = fstat(arg0, &s);
368 if (result == 0) {
369 translate_stat(env, arg1, &s);
370 }
371 }
372 break;
373 case HOSTED_GETTIMEOFDAY:
374 GET_ARG(0);
375 GET_ARG(1);
376 if (use_gdb_syscalls()) {
377 gdb_do_syscall(m68k_semi_cb, "gettimeofday,%x,%x",
378 arg0, arg1);
379 return;
380 } else {
381 qemu_timeval tv;
382 struct gdb_timeval *p;
383 result = qemu_gettimeofday(&tv);
384 if (result != 0) {
385 if (!(p = lock_user(VERIFY_WRITE,
386 arg0, sizeof(struct gdb_timeval), 0))) {
387 /* FIXME - check error code? */
388 result = -1;
389 } else {
390 p->tv_sec = cpu_to_be32(tv.tv_sec);
391 p->tv_usec = cpu_to_be64(tv.tv_usec);
392 unlock_user(p, arg0, sizeof(struct gdb_timeval));
393 }
394 }
395 }
396 break;
397 case HOSTED_ISATTY:
398 GET_ARG(0);
399 if (use_gdb_syscalls()) {
400 gdb_do_syscall(m68k_semi_cb, "isatty,%x", arg0);
401 return;
402 } else {
403 result = isatty(arg0);
404 }
405 break;
406 case HOSTED_SYSTEM:
407 GET_ARG(0);
408 GET_ARG(1);
409 if (use_gdb_syscalls()) {
410 gdb_do_syscall(m68k_semi_cb, "system,%s",
411 arg0, (int)arg1);
412 return;
413 } else {
414 p = lock_user_string(arg0);
415 if (!p) {
416 /* FIXME - check error code? */
417 result = -1;
418 } else {
419 result = system(p);
420 unlock_user(p, arg0, 0);
421 }
422 }
423 break;
424 case HOSTED_INIT_SIM:
425 #if defined(CONFIG_USER_ONLY)
426 {
427 CPUState *cs = env_cpu(env);
428 TaskState *ts = cs->opaque;
429 /* Allocate the heap using sbrk. */
430 if (!ts->heap_limit) {
431 abi_ulong ret;
432 uint32_t size;
433 uint32_t base;
434
435 base = do_brk(0);
436 size = SEMIHOSTING_HEAP_SIZE;
437 /* Try a big heap, and reduce the size if that fails. */
438 for (;;) {
439 ret = do_brk(base + size);
440 if (ret >= (base + size)) {
441 break;
442 }
443 size >>= 1;
444 }
445 ts->heap_limit = base + size;
446 }
447 /*
448 * This call may happen before we have writable memory, so return
449 * values directly in registers.
450 */
451 env->dregs[1] = ts->heap_limit;
452 env->aregs[7] = ts->stack_base;
453 }
454 #else
455 /*
456 * FIXME: This is wrong for boards where RAM does not start at
457 * address zero.
458 */
459 env->dregs[1] = current_machine->ram_size;
460 env->aregs[7] = current_machine->ram_size;
461 #endif
462 return;
463 default:
464 cpu_abort(env_cpu(env), "Unsupported semihosting syscall %d\n", nr);
465 result = 0;
466 }
467 failed:
468 m68k_semi_return_u32(env, result, errno);
469 }
470