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 #include "softmmu-semi.h"
 116 #endif
 117
 118 static target_ulong arm_semi_syscall_len;
 119
 120 static void arm_semi_cb(CPUState *env, target_ulong ret, target_ulong err)
 121 {
 122 #ifdef CONFIG_USER_ONLY
 123     TaskState *ts = env->opaque;
 124 #endif
 125     if (ret == (target_ulong)-1) {
 126 #ifdef CONFIG_USER_ONLY
 127         ts->swi_errno = err;
 128 #endif
 129         env->regs[0] = ret;
 130     } else {
 131         /* Fixup syscalls that use nonstardard return conventions.  */
 132         switch (env->regs[0]) {
 133         case SYS_WRITE:
 134         case SYS_READ:
 135             env->regs[0] = arm_semi_syscall_len - ret;
 136             break;
 137         case SYS_SEEK:
 138             env->regs[0] = 0;
 139             break;
 140         default:
 141             env->regs[0] = ret;
 142             break;
 143         }
 144     }
 145 }
 146
 147 #define ARG(n) tget32(args + (n) * 4)
 148 #define SET_ARG(n, val) tput32(args + (n) * 4,val)
 149 uint32_t do_arm_semihosting(CPUState *env)
 150 {
 151     target_ulong args;
 152     char * s;
 153     int nr;
 154     uint32_t ret;
 155     uint32_t len;
 156 #ifdef CONFIG_USER_ONLY
 157     TaskState *ts = env->opaque;
 158 #else
 159     CPUState *ts = env;
 160 #endif
 161
 162     nr = env->regs[0];
 163     args = env->regs[1];
 164     switch (nr) {
 165     case SYS_OPEN:
 166         s = lock_user_string(ARG(0));
 167         if (ARG(1) >= 12)
 168           return (uint32_t)-1;
 169         if (strcmp(s, ":tt") == 0) {
 170             if (ARG(1) < 4)
 171                 return STDIN_FILENO;
 172             else
 173                 return STDOUT_FILENO;
 174         }
 175         if (use_gdb_syscalls()) {
 176             gdb_do_syscall(arm_semi_cb, "open,%s,%x,1a4", ARG(0), (int)ARG(2),
 177                            gdb_open_modeflags[ARG(1)]);
 178             return env->regs[0];
 179         } else {
 180             ret = set_swi_errno(ts, open(s, open_modeflags[ARG(1)], 0644));
 181         }
 182         unlock_user(s, ARG(0), 0);
 183         return ret;
 184     case SYS_CLOSE:
 185         if (use_gdb_syscalls()) {
 186             gdb_do_syscall(arm_semi_cb, "close,%x", ARG(0));
 187             return env->regs[0];
 188         } else {
 189             return set_swi_errno(ts, close(ARG(0)));
 190         }
 191     case SYS_WRITEC:
 192         {
 193           char c = tget8(args);
 194           /* Write to debug console.  stderr is near enough.  */
 195           if (use_gdb_syscalls()) {
 196                 gdb_do_syscall(arm_semi_cb, "write,2,%x,1", args);
 197                 return env->regs[0];
 198           } else {
 199                 return write(STDERR_FILENO, &c, 1);
 200           }
 201         }
 202     case SYS_WRITE0:
 203         s = lock_user_string(args);
 204         len = strlen(s);
 205         if (use_gdb_syscalls()) {
 206             gdb_do_syscall(arm_semi_cb, "write,2,%x,%x\n", args, len);
 207             ret = env->regs[0];
 208         } else {
 209             ret = write(STDERR_FILENO, s, len);
 210         }
 211         unlock_user(s, args, 0);
 212         return ret;
 213     case SYS_WRITE:
 214         len = ARG(2);
 215         if (use_gdb_syscalls()) {
 216             arm_semi_syscall_len = len;
 217             gdb_do_syscall(arm_semi_cb, "write,%x,%x,%x", ARG(0), ARG(1), len);
 218             return env->regs[0];
 219         } else {
 220             s = lock_user(ARG(1), len, 1);
 221             ret = set_swi_errno(ts, write(ARG(0), s, len));
 222             unlock_user(s, ARG(1), 0);
 223             if (ret == (uint32_t)-1)
 224                 return -1;
 225             return len - ret;
 226         }
 227     case SYS_READ:
 228         len = ARG(2);
 229         if (use_gdb_syscalls()) {
 230             arm_semi_syscall_len = len;
 231             gdb_do_syscall(arm_semi_cb, "read,%x,%x,%x", ARG(0), ARG(1), len);
 232             return env->regs[0];
 233         } else {
 234             s = lock_user(ARG(1), len, 0);
 235             do
 236               ret = set_swi_errno(ts, read(ARG(0), s, len));
 237             while (ret == -1 && errno == EINTR);
 238             unlock_user(s, ARG(1), len);
 239             if (ret == (uint32_t)-1)
 240                 return -1;
 241             return len - ret;
 242         }
 243     case SYS_READC:
 244        /* XXX: Read from debug cosole. Not implemented.  */
 245         return 0;
 246     case SYS_ISTTY:
 247         if (use_gdb_syscalls()) {
 248             gdb_do_syscall(arm_semi_cb, "isatty,%x", ARG(0));
 249             return env->regs[0];
 250         } else {
 251             return isatty(ARG(0));
 252         }
 253     case SYS_SEEK:
 254         if (use_gdb_syscalls()) {
 255             gdb_do_syscall(arm_semi_cb, "fseek,%x,%x,0", ARG(0), ARG(1));
 256             return env->regs[0];
 257         } else {
 258             ret = set_swi_errno(ts, lseek(ARG(0), ARG(1), SEEK_SET));
 259             if (ret == (uint32_t)-1)
 260               return -1;
 261             return 0;
 262         }
 263     case SYS_FLEN:
 264         if (use_gdb_syscalls()) {
 265             /* TODO: Use stat syscall.  */
 266             return -1;
 267         } else {
 268             struct stat buf;
 269             ret = set_swi_errno(ts, fstat(ARG(0), &buf));
 270             if (ret == (uint32_t)-1)
 271                 return -1;
 272             return buf.st_size;
 273         }
 274     case SYS_TMPNAM:
 275         /* XXX: Not implemented.  */
 276         return -1;
 277     case SYS_REMOVE:
 278         if (use_gdb_syscalls()) {
 279             gdb_do_syscall(arm_semi_cb, "unlink,%s", ARG(0), (int)ARG(1));
 280             ret = env->regs[0];
 281         } else {
 282             s = lock_user_string(ARG(0));
 283             ret =  set_swi_errno(ts, remove(s));
 284             unlock_user(s, ARG(0), 0);
 285         }
 286         return ret;
 287     case SYS_RENAME:
 288         if (use_gdb_syscalls()) {
 289             gdb_do_syscall(arm_semi_cb, "rename,%s,%s",
 290                            ARG(0), (int)ARG(1), ARG(2), (int)ARG(3));
 291             return env->regs[0];
 292         } else {
 293             char *s2;
 294             s = lock_user_string(ARG(0));
 295             s2 = lock_user_string(ARG(2));
 296             ret = set_swi_errno(ts, rename(s, s2));
 297             unlock_user(s2, ARG(2), 0);
 298             unlock_user(s, ARG(0), 0);
 299             return ret;
 300         }
 301     case SYS_CLOCK:
 302         return clock() / (CLOCKS_PER_SEC / 100);
 303     case SYS_TIME:
 304         return set_swi_errno(ts, time(NULL));
 305     case SYS_SYSTEM:
 306         if (use_gdb_syscalls()) {
 307             gdb_do_syscall(arm_semi_cb, "system,%s", ARG(0), (int)ARG(1));
 308             return env->regs[0];
 309         } else {
 310             s = lock_user_string(ARG(0));
 311             ret = set_swi_errno(ts, system(s));
 312             unlock_user(s, ARG(0), 0);
 313         }
 314     case SYS_ERRNO:
 315 #ifdef CONFIG_USER_ONLY
 316         return ts->swi_errno;
 317 #else
 318         return 0;
 319 #endif
 320     case SYS_GET_CMDLINE:
 321 #ifdef CONFIG_USER_ONLY
 322         /* Build a commandline from the original argv.  */
 323         {
 324             char **arg = ts->info->host_argv;
 325             int len = ARG(1);
 326             /* lock the buffer on the ARM side */
 327             char *cmdline_buffer = (char*)lock_user(ARG(0), len, 0);
 328
 329             s = cmdline_buffer;
 330             while (*arg && len > 2) {
 331                 int n = strlen(*arg);
 332
 333                 if (s != cmdline_buffer) {
 334                     *(s++) = ' ';
 335                     len--;
 336                 }
 337                 if (n >= len)
 338                     n = len - 1;
 339                 memcpy(s, *arg, n);
 340                 s += n;
 341                 len -= n;
 342                 arg++;
 343             }
 344             /* Null terminate the string.  */
 345             *s = 0;
 346             len = s - cmdline_buffer;
 347
 348             /* Unlock the buffer on the ARM side.  */
 349             unlock_user(cmdline_buffer, ARG(0), len);
 350
 351             /* Adjust the commandline length argument.  */
 352             SET_ARG(1, len);
 353
 354             /* Return success if commandline fit into buffer.  */
 355             return *arg ? -1 : 0;
 356         }
 357 #else
 358       return -1;
 359 #endif
 360     case SYS_HEAPINFO:
 361         {
 362             uint32_t *ptr;
 363             uint32_t limit;
 364
 365 #ifdef CONFIG_USER_ONLY
 366             /* Some C libraries assume the heap immediately follows .bss, so
 367                allocate it using sbrk.  */
 368             if (!ts->heap_limit) {
 369                 long ret;
 370
 371                 ts->heap_base = do_brk(0);
 372                 limit = ts->heap_base + ARM_ANGEL_HEAP_SIZE;
 373                 /* Try a big heap, and reduce the size if that fails.  */
 374                 for (;;) {
 375                     ret = do_brk(limit);
 376                     if (ret != -1)
 377                         break;
 378                     limit = (ts->heap_base >> 1) + (limit >> 1);
 379                 }
 380                 ts->heap_limit = limit;
 381             }
 382
 383             ptr = lock_user(ARG(0), 16, 0);
 384             ptr[0] = tswap32(ts->heap_base);
 385             ptr[1] = tswap32(ts->heap_limit);
 386             ptr[2] = tswap32(ts->stack_base);
 387             ptr[3] = tswap32(0); /* Stack limit.  */
 388             unlock_user(ptr, ARG(0), 16);
 389 #else
 390             limit = ram_size;
 391             ptr = lock_user(ARG(0), 16, 0);
 392             /* TODO: Make this use the limit of the loaded application.  */
 393             ptr[0] = tswap32(limit / 2);
 394             ptr[1] = tswap32(limit);
 395             ptr[2] = tswap32(limit); /* Stack base */
 396             ptr[3] = tswap32(0); /* Stack limit.  */
 397             unlock_user(ptr, ARG(0), 16);
 398 #endif
 399             return 0;
 400         }
 401     case SYS_EXIT:
 402         exit(0);
 403     default:
 404         fprintf(stderr, "qemu: Unsupported SemiHosting SWI 0x%02x\n", nr);
 405         cpu_dump_state(env, stderr, fprintf, 0);
 406         abort();
 407     }
 408 }