arm-semi.c

   1 /*
   2  *  Arm "Angel" semihosting syscalls
   3  *
   4  *  Copyright (c) 2005, 2007 CodeSourcery.
   5  *  Written by Paul Brook.
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License as published by
   9  *  the Free Software Foundation; either version 2 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  This program is distributed in the hope that it will be useful,
  13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  *  GNU General Public License for more details.
  16  *
  17  *  You should have received a copy of the GNU General Public License
  18  *  along with this program; if not, write to the Free Software
  19  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20  */
  21
  22 #include <sys/types.h>
  23 #include <sys/stat.h>
  24 #include <fcntl.h>
  25 #include <unistd.h>
  26 #include <stdlib.h>
  27 #include <stdio.h>
  28 #include <time.h>
  29
  30 #include "cpu.h"
  31 #ifdef CONFIG_USER_ONLY
  32 #include "qemu.h"
  33
  34 #define ARM_ANGEL_HEAP_SIZE (128 * 1024 * 1024)
  35 #else
  36 #include "vl.h"
  37 #endif
  38
  39 #define SYS_OPEN        0x01
  40 #define SYS_CLOSE       0x02
  41 #define SYS_WRITEC      0x03
  42 #define SYS_WRITE0      0x04
  43 #define SYS_WRITE       0x05
  44 #define SYS_READ        0x06
  45 #define SYS_READC       0x07
  46 #define SYS_ISTTY       0x09
  47 #define SYS_SEEK        0x0a
  48 #define SYS_FLEN        0x0c
  49 #define SYS_TMPNAM      0x0d
  50 #define SYS_REMOVE      0x0e
  51 #define SYS_RENAME      0x0f
  52 #define SYS_CLOCK       0x10
  53 #define SYS_TIME        0x11
  54 #define SYS_SYSTEM      0x12
  55 #define SYS_ERRNO       0x13
  56 #define SYS_GET_CMDLINE 0x15
  57 #define SYS_HEAPINFO    0x16
  58 #define SYS_EXIT        0x18
  59
  60 #ifndef O_BINARY
  61 #define O_BINARY 0
  62 #endif
  63
  64 #define GDB_O_RDONLY  0x000
  65 #define GDB_O_WRONLY  0x001
  66 #define GDB_O_RDWR    0x002
  67 #define GDB_O_APPEND  0x008
  68 #define GDB_O_CREAT   0x200
  69 #define GDB_O_TRUNC   0x400
  70 #define GDB_O_BINARY  0
  71
  72 static int gdb_open_modeflags[12] = {
  73     GDB_O_RDONLY,
  74     GDB_O_RDONLY | GDB_O_BINARY,
  75     GDB_O_RDWR,
  76     GDB_O_RDWR | GDB_O_BINARY,
  77     GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC,
  78     GDB_O_WRONLY | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY,
  79     GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC,
  80     GDB_O_RDWR | GDB_O_CREAT | GDB_O_TRUNC | GDB_O_BINARY,
  81     GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND,
  82     GDB_O_WRONLY | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY,
  83     GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND,
  84     GDB_O_RDWR | GDB_O_CREAT | GDB_O_APPEND | GDB_O_BINARY
  85 };
  86
  87 static int open_modeflags[12] = {
  88     O_RDONLY,
  89     O_RDONLY | O_BINARY,
  90     O_RDWR,
  91     O_RDWR | O_BINARY,
  92     O_WRONLY | O_CREAT | O_TRUNC,
  93     O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
  94     O_RDWR | O_CREAT | O_TRUNC,
  95     O_RDWR | O_CREAT | O_TRUNC | O_BINARY,
  96     O_WRONLY | O_CREAT | O_APPEND,
  97     O_WRONLY | O_CREAT | O_APPEND | O_BINARY,
  98     O_RDWR | O_CREAT | O_APPEND,
  99     O_RDWR | O_CREAT | O_APPEND | O_BINARY
 100 };
 101
 102 #ifdef CONFIG_USER_ONLY
 103 static inline uint32_t set_swi_errno(TaskState *ts, uint32_t code)
 104 {
 105     if (code == (uint32_t)-1)
 106         ts->swi_errno = errno;
 107     return code;
 108 }
 109 #else
 110 static inline uint32_t set_swi_errno(CPUState *env, uint32_t code)
 111 {
 112     return code;
 113 }
 114
 115 static uint32_t softmmu_tget32(CPUState *env, uint32_t addr)
 116 {
 117     uint32_t val;
 118
 119     cpu_memory_rw_debug(env, addr, (uint8_t *)&val, 4, 0);
 120     return tswap32(val);
 121 }
 122 static uint32_t softmmu_tget8(CPUState *env, uint32_t addr)
 123 {
 124     uint8_t val;
 125
 126     cpu_memory_rw_debug(env, addr, &val, 1, 0);
 127     return val;
 128 }
 129 #define tget32(p) softmmu_tget32(env, p)
 130 #define tget8(p) softmmu_tget8(env, p)
 131
 132 static void *softmmu_lock_user(CPUState *env, uint32_t addr, uint32_t len,
 133                                int copy)
 134 {
 135     char *p;
 136     /* TODO: Make this something that isn't fixed size.  */
 137     p = malloc(len);
 138     if (copy)
 139         cpu_memory_rw_debug(env, addr, p, len, 0);
 140     return p;
 141 }
 142 #define lock_user(p, len, copy) softmmu_lock_user(env, p, len, copy)
 143 static char *softmmu_lock_user_string(CPUState *env, uint32_t addr)
 144 {
 145     char *p;
 146     char *s;
 147     uint8_t c;
 148     /* TODO: Make this something that isn't fixed size.  */
 149     s = p = malloc(1024);
 150     do {
 151         cpu_memory_rw_debug(env, addr, &c, 1, 0);
 152         addr++;
 153         *(p++) = c;
 154     } while (c);
 155     return s;
 156 }
 157 #define lock_user_string(p) softmmu_lock_user_string(env, p)
 158 static void softmmu_unlock_user(CPUState *env, void *p, target_ulong addr,
 159                                 target_ulong len)
 160 {
 161     if (len)
 162         cpu_memory_rw_debug(env, addr, p, len, 1);
 163     free(p);
 164 }
 165 #define unlock_user(s, args, len) softmmu_unlock_user(env, s, args, len)
 166 #endif
 167
 168 static target_ulong arm_semi_syscall_len;
 169
 170 static void arm_semi_cb(CPUState *env, target_ulong ret, target_ulong err)
 171 {
 172 #ifdef CONFIG_USER_ONLY
 173     TaskState *ts = env->opaque;
 174 #endif
 175     if (ret == (target_ulong)-1) {
 176 #ifdef CONFIG_USER_ONLY
 177         ts->swi_errno = err;
 178 #endif
 179         env->regs[0] = ret;
 180     } else {
 181         /* Fixup syscalls that use nonstardard return conventions.  */
 182         switch (env->regs[0]) {
 183         case SYS_WRITE:
 184         case SYS_READ:
 185             env->regs[0] = arm_semi_syscall_len - ret;
 186             break;
 187         case SYS_SEEK:
 188             env->regs[0] = 0;
 189             break;
 190         default:
 191             env->regs[0] = ret;
 192             break;
 193         }
 194     }
 195 }
 196
 197 #define ARG(n) tget32(args + (n) * 4)
 198 #define SET_ARG(n, val) tput32(args + (n) * 4,val)
 199 uint32_t do_arm_semihosting(CPUState *env)
 200 {
 201     target_ulong args;
 202     char * s;
 203     int nr;
 204     uint32_t ret;
 205     uint32_t len;
 206 #ifdef CONFIG_USER_ONLY
 207     TaskState *ts = env->opaque;
 208 #else
 209     CPUState *ts = env;
 210 #endif
 211
 212     nr = env->regs[0];
 213     args = env->regs[1];
 214     switch (nr) {
 215     case SYS_OPEN:
 216         s = lock_user_string(ARG(0));
 217         if (ARG(1) >= 12)
 218           return (uint32_t)-1;
 219         if (strcmp(s, ":tt") == 0) {
 220             if (ARG(1) < 4)
 221                 return STDIN_FILENO;
 222             else
 223                 return STDOUT_FILENO;
 224         }
 225         if (use_gdb_syscalls()) {
 226             gdb_do_syscall(arm_semi_cb, "open,%s,%x,1a4", ARG(0), (int)ARG(2),
 227                            gdb_open_modeflags[ARG(1)]);
 228             return env->regs[0];
 229         } else {
 230             ret = set_swi_errno(ts, open(s, open_modeflags[ARG(1)], 0644));
 231         }
 232         unlock_user(s, ARG(0), 0);
 233         return ret;
 234     case SYS_CLOSE:
 235         if (use_gdb_syscalls()) {
 236             gdb_do_syscall(arm_semi_cb, "close,%x", ARG(0));
 237             return env->regs[0];
 238         } else {
 239             return set_swi_errno(ts, close(ARG(0)));
 240         }
 241     case SYS_WRITEC:
 242         {
 243           char c = tget8(args);
 244           /* Write to debug console.  stderr is near enough.  */
 245           if (use_gdb_syscalls()) {
 246                 gdb_do_syscall(arm_semi_cb, "write,2,%x,1", args);
 247                 return env->regs[0];
 248           } else {
 249                 return write(STDERR_FILENO, &c, 1);
 250           }
 251         }
 252     case SYS_WRITE0:
 253         s = lock_user_string(args);
 254         len = strlen(s);
 255         if (use_gdb_syscalls()) {
 256             gdb_do_syscall(arm_semi_cb, "write,2,%x,%x\n", args, len);
 257             ret = env->regs[0];
 258         } else {
 259             ret = write(STDERR_FILENO, s, len);
 260         }
 261         unlock_user(s, args, 0);
 262         return ret;
 263     case SYS_WRITE:
 264         len = ARG(2);
 265         if (use_gdb_syscalls()) {
 266             arm_semi_syscall_len = len;
 267             gdb_do_syscall(arm_semi_cb, "write,%x,%x,%x", ARG(0), ARG(1), len);
 268             return env->regs[0];
 269         } else {
 270             s = lock_user(ARG(1), len, 1);
 271             ret = set_swi_errno(ts, write(ARG(0), s, len));
 272             unlock_user(s, ARG(1), 0);
 273             if (ret == (uint32_t)-1)
 274                 return -1;
 275             return len - ret;
 276         }
 277     case SYS_READ:
 278         len = ARG(2);
 279         if (use_gdb_syscalls()) {
 280             arm_semi_syscall_len = len;
 281             gdb_do_syscall(arm_semi_cb, "read,%x,%x,%x", ARG(0), ARG(1), len);
 282             return env->regs[0];
 283         } else {
 284             s = lock_user(ARG(1), len, 0);
 285             do
 286               ret = set_swi_errno(ts, read(ARG(0), s, len));
 287             while (ret == -1 && errno == EINTR);
 288             unlock_user(s, ARG(1), len);
 289             if (ret == (uint32_t)-1)
 290                 return -1;
 291             return len - ret;
 292         }
 293     case SYS_READC:
 294        /* XXX: Read from debug cosole. Not implemented.  */
 295         return 0;
 296     case SYS_ISTTY:
 297         if (use_gdb_syscalls()) {
 298             gdb_do_syscall(arm_semi_cb, "isatty,%x", ARG(0));
 299             return env->regs[0];
 300         } else {
 301             return isatty(ARG(0));
 302         }
 303     case SYS_SEEK:
 304         if (use_gdb_syscalls()) {
 305             gdb_do_syscall(arm_semi_cb, "fseek,%x,%x,0", ARG(0), ARG(1));
 306             return env->regs[0];
 307         } else {
 308             ret = set_swi_errno(ts, lseek(ARG(0), ARG(1), SEEK_SET));
 309             if (ret == (uint32_t)-1)
 310               return -1;
 311             return 0;
 312         }
 313     case SYS_FLEN:
 314         if (use_gdb_syscalls()) {
 315             /* TODO: Use stat syscall.  */
 316             return -1;
 317         } else {
 318             struct stat buf;
 319             ret = set_swi_errno(ts, fstat(ARG(0), &buf));
 320             if (ret == (uint32_t)-1)
 321                 return -1;
 322             return buf.st_size;
 323         }
 324     case SYS_TMPNAM:
 325         /* XXX: Not implemented.  */
 326         return -1;
 327     case SYS_REMOVE:
 328         if (use_gdb_syscalls()) {
 329             gdb_do_syscall(arm_semi_cb, "unlink,%s", ARG(0), (int)ARG(1));
 330             ret = env->regs[0];
 331         } else {
 332             s = lock_user_string(ARG(0));
 333             ret =  set_swi_errno(ts, remove(s));
 334             unlock_user(s, ARG(0), 0);
 335         }
 336         return ret;
 337     case SYS_RENAME:
 338         if (use_gdb_syscalls()) {
 339             gdb_do_syscall(arm_semi_cb, "rename,%s,%s",
 340                            ARG(0), (int)ARG(1), ARG(2), (int)ARG(3));
 341             return env->regs[0];
 342         } else {
 343             char *s2;
 344             s = lock_user_string(ARG(0));
 345             s2 = lock_user_string(ARG(2));
 346             ret = set_swi_errno(ts, rename(s, s2));
 347             unlock_user(s2, ARG(2), 0);
 348             unlock_user(s, ARG(0), 0);
 349             return ret;
 350         }
 351     case SYS_CLOCK:
 352         return clock() / (CLOCKS_PER_SEC / 100);
 353     case SYS_TIME:
 354         return set_swi_errno(ts, time(NULL));
 355     case SYS_SYSTEM:
 356         if (use_gdb_syscalls()) {
 357             gdb_do_syscall(arm_semi_cb, "system,%s", ARG(0), (int)ARG(1));
 358             return env->regs[0];
 359         } else {
 360             s = lock_user_string(ARG(0));
 361             ret = set_swi_errno(ts, system(s));
 362             unlock_user(s, ARG(0), 0);
 363         }
 364     case SYS_ERRNO:
 365 #ifdef CONFIG_USER_ONLY
 366         return ts->swi_errno;
 367 #else
 368         return 0;
 369 #endif
 370     case SYS_GET_CMDLINE:
 371 #ifdef CONFIG_USER_ONLY
 372         /* Build a commandline from the original argv.  */
 373         {
 374             char **arg = ts->info->host_argv;
 375             int len = ARG(1);
 376             /* lock the buffer on the ARM side */
 377             char *cmdline_buffer = (char*)lock_user(ARG(0), len, 0);
 378
 379             s = cmdline_buffer;
 380             while (*arg && len > 2) {
 381                 int n = strlen(*arg);
 382
 383                 if (s != cmdline_buffer) {
 384                     *(s++) = ' ';
 385                     len--;
 386                 }
 387                 if (n >= len)
 388                     n = len - 1;
 389                 memcpy(s, *arg, n);
 390                 s += n;
 391                 len -= n;
 392                 arg++;
 393             }
 394             /* Null terminate the string.  */
 395             *s = 0;
 396             len = s - cmdline_buffer;
 397
 398             /* Unlock the buffer on the ARM side.  */
 399             unlock_user(cmdline_buffer, ARG(0), len);
 400
 401             /* Adjust the commandline length argument.  */
 402             SET_ARG(1, len);
 403
 404             /* Return success if commandline fit into buffer.  */
 405             return *arg ? -1 : 0;
 406         }
 407 #else
 408       return -1;
 409 #endif
 410     case SYS_HEAPINFO:
 411         {
 412             uint32_t *ptr;
 413             uint32_t limit;
 414
 415 #ifdef CONFIG_USER_ONLY
 416             /* Some C libraries assume the heap immediately follows .bss, so
 417                allocate it using sbrk.  */
 418             if (!ts->heap_limit) {
 419                 long ret;
 420
 421                 ts->heap_base = do_brk(0);
 422                 limit = ts->heap_base + ARM_ANGEL_HEAP_SIZE;
 423                 /* Try a big heap, and reduce the size if that fails.  */
 424                 for (;;) {
 425                     ret = do_brk(limit);
 426                     if (ret != -1)
 427                         break;
 428                     limit = (ts->heap_base >> 1) + (limit >> 1);
 429                 }
 430                 ts->heap_limit = limit;
 431             }
 432
 433             ptr = lock_user(ARG(0), 16, 0);
 434             ptr[0] = tswap32(ts->heap_base);
 435             ptr[1] = tswap32(ts->heap_limit);
 436             ptr[2] = tswap32(ts->stack_base);
 437             ptr[3] = tswap32(0); /* Stack limit.  */
 438             unlock_user(ptr, ARG(0), 16);
 439 #else
 440             limit = ram_size;
 441             ptr = lock_user(ARG(0), 16, 0);
 442             /* TODO: Make this use the limit of the loaded application.  */
 443             ptr[0] = tswap32(limit / 2);
 444             ptr[1] = tswap32(limit);
 445             ptr[2] = tswap32(limit); /* Stack base */
 446             ptr[3] = tswap32(0); /* Stack limit.  */
 447             unlock_user(ptr, ARG(0), 16);
 448 #endif
 449             return 0;
 450         }
 451     case SYS_EXIT:
 452         exit(0);
 453     default:
 454         fprintf(stderr, "qemu: Unsupported SemiHosting SWI 0x%02x\n", nr);
 455         cpu_dump_state(env, stderr, fprintf, 0);
 456         abort();
 457     }
 458 }