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 #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 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 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 } 127 128 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 } 142 143 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; 156 157 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) 185 186 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, 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