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 int open_modeflags[12] = {
  65     O_RDONLY,
  66     O_RDONLY | O_BINARY,
  67     O_RDWR,
  68     O_RDWR | O_BINARY,
  69     O_WRONLY | O_CREAT | O_TRUNC,
  70     O_WRONLY | O_CREAT | O_TRUNC | O_BINARY,
  71     O_RDWR | O_CREAT | O_TRUNC,
  72     O_RDWR | O_CREAT | O_TRUNC | O_BINARY,
  73     O_WRONLY | O_CREAT | O_APPEND,
  74     O_WRONLY | O_CREAT | O_APPEND | O_BINARY,
  75     O_RDWR | O_CREAT | O_APPEND,
  76     O_RDWR | O_CREAT | O_APPEND | O_BINARY
  77 };
  78
  79 #ifdef CONFIG_USER_ONLY
  80 static inline uint32_t set_swi_errno(TaskState *ts, uint32_t code)
  81 {
  82     if (code == (uint32_t)-1)
  83         ts->swi_errno = errno;
  84     return code;
  85 }
  86 #else
  87 static inline uint32_t set_swi_errno(CPUState *env, uint32_t code)
  88 {
  89     return code;
  90 }
  91
  92 static uint32_t softmmu_tget32(CPUState *env, uint32_t addr)
  93 {
  94     uint32_t val;
  95
  96     cpu_memory_rw_debug(env, addr, (uint8_t *)&val, 4, 0);
  97     return tswap32(val);
  98 }
  99 static uint32_t softmmu_tget8(CPUState *env, uint32_t addr)
 100 {
 101     uint8_t val;
 102
 103     cpu_memory_rw_debug(env, addr, &val, 1, 0);
 104     return val;
 105 }
 106 #define tget32(p) softmmu_tget32(env, p)
 107 #define tget8(p) softmmu_tget8(env, p)
 108
 109 static void *softmmu_lock_user(CPUState *env, uint32_t addr, uint32_t len,
 110                                int copy)
 111 {
 112     char *p;
 113     /* TODO: Make this something that isn't fixed size.  */
 114     p = malloc(len);
 115     if (copy)
 116         cpu_memory_rw_debug(env, addr, p, len, 0);
 117     return p;
 118 }
 119 #define lock_user(p, len, copy) softmmu_lock_user(env, p, len, copy)
 120 static char *softmmu_lock_user_string(CPUState *env, uint32_t addr)
 121 {
 122     char *p;
 123     char *s;
 124     uint8_t c;
 125     /* TODO: Make this something that isn't fixed size.  */
 126     s = p = malloc(1024);
 127     do {
 128         cpu_memory_rw_debug(env, addr, &c, 1, 0);
 129         addr++;
 130         *(p++) = c;
 131     } while (c);
 132     return s;
 133 }
 134 #define lock_user_string(p) softmmu_lock_user_string(env, p)
 135 static void softmmu_unlock_user(CPUState *env, void *p, target_ulong addr,
 136                                 target_ulong len)
 137 {
 138     if (len)
 139         cpu_memory_rw_debug(env, addr, p, len, 1);
 140     free(p);
 141 }
 142 #define unlock_user(s, args, len) softmmu_unlock_user(env, s, args, len)
 143 #endif
 144
 145 #define ARG(n) tget32(args + (n) * 4)
 146 #define SET_ARG(n, val) tput32(args + (n) * 4,val)
 147 uint32_t do_arm_semihosting(CPUState *env)
 148 {
 149     target_ulong args;
 150     char * s;
 151     int nr;
 152     uint32_t ret;
 153     uint32_t len;
 154 #ifdef CONFIG_USER_ONLY
 155     TaskState *ts = env->opaque;
 156 #else
 157     CPUState *ts = env;
 158 #endif
 159
 160     nr = env->regs[0];
 161     args = env->regs[1];
 162     switch (nr) {
 163     case SYS_OPEN:
 164         s = lock_user_string(ARG(0));
 165         if (ARG(1) >= 12)
 166           return (uint32_t)-1;
 167         if (strcmp(s, ":tt") == 0) {
 168             if (ARG(1) < 4)
 169                 return STDIN_FILENO;
 170             else
 171                 return STDOUT_FILENO;
 172         }
 173         ret = set_swi_errno(ts, open(s, open_modeflags[ARG(1)], 0644));
 174         unlock_user(s, ARG(0), 0);
 175         return ret;
 176     case SYS_CLOSE:
 177         return set_swi_errno(ts, close(ARG(0)));
 178     case SYS_WRITEC:
 179         {
 180           char c = tget8(args);
 181           /* Write to debug console.  stderr is near enough.  */
 182           return write(STDERR_FILENO, &c, 1);
 183         }
 184     case SYS_WRITE0:
 185         s = lock_user_string(args);
 186         ret = write(STDERR_FILENO, s, strlen(s));
 187         unlock_user(s, args, 0);
 188         return ret;
 189     case SYS_WRITE:
 190         len = ARG(2);
 191         s = lock_user(ARG(1), len, 1);
 192         ret = set_swi_errno(ts, write(ARG(0), s, len));
 193         unlock_user(s, ARG(1), 0);
 194         if (ret == (uint32_t)-1)
 195             return -1;
 196         return ARG(2) - ret;
 197     case SYS_READ:
 198         len = ARG(2);
 199         s = lock_user(ARG(1), len, 0);
 200         do
 201           ret = set_swi_errno(ts, read(ARG(0), s, len));
 202         while (ret == -1 && errno == EINTR);
 203         unlock_user(s, ARG(1), len);
 204         if (ret == (uint32_t)-1)
 205             return -1;
 206         return ARG(2) - ret;
 207     case SYS_READC:
 208        /* XXX: Read from debug cosole. Not implemented.  */
 209         return 0;
 210     case SYS_ISTTY:
 211         return isatty(ARG(0));
 212     case SYS_SEEK:
 213         ret = set_swi_errno(ts, lseek(ARG(0), ARG(1), SEEK_SET));
 214         if (ret == (uint32_t)-1)
 215           return -1;
 216         return 0;
 217     case SYS_FLEN:
 218         {
 219             struct stat buf;
 220             ret = set_swi_errno(ts, fstat(ARG(0), &buf));
 221             if (ret == (uint32_t)-1)
 222                 return -1;
 223             return buf.st_size;
 224         }
 225     case SYS_TMPNAM:
 226         /* XXX: Not implemented.  */
 227         return -1;
 228     case SYS_REMOVE:
 229         s = lock_user_string(ARG(0));
 230         ret =  set_swi_errno(ts, remove(s));
 231         unlock_user(s, ARG(0), 0);
 232         return ret;
 233     case SYS_RENAME:
 234         {
 235             char *s2;
 236             s = lock_user_string(ARG(0));
 237             s2 = lock_user_string(ARG(2));
 238             ret = set_swi_errno(ts, rename(s, s2));
 239             unlock_user(s2, ARG(2), 0);
 240             unlock_user(s, ARG(0), 0);
 241             return ret;
 242         }
 243     case SYS_CLOCK:
 244         return clock() / (CLOCKS_PER_SEC / 100);
 245     case SYS_TIME:
 246         return set_swi_errno(ts, time(NULL));
 247     case SYS_SYSTEM:
 248         s = lock_user_string(ARG(0));
 249         ret = set_swi_errno(ts, system(s));
 250         unlock_user(s, ARG(0), 0);
 251     case SYS_ERRNO:
 252 #ifdef CONFIG_USER_ONLY
 253         return ts->swi_errno;
 254 #else
 255         return 0;
 256 #endif
 257     case SYS_GET_CMDLINE:
 258 #ifdef CONFIG_USER_ONLY
 259         /* Build a commandline from the original argv.  */
 260         {
 261             char **arg = ts->info->host_argv;
 262             int len = ARG(1);
 263             /* lock the buffer on the ARM side */
 264             char *cmdline_buffer = (char*)lock_user(ARG(0), len, 0);
 265
 266             s = cmdline_buffer;
 267             while (*arg && len > 2) {
 268                 int n = strlen(*arg);
 269
 270                 if (s != cmdline_buffer) {
 271                     *(s++) = ' ';
 272                     len--;
 273                 }
 274                 if (n >= len)
 275                     n = len - 1;
 276                 memcpy(s, *arg, n);
 277                 s += n;
 278                 len -= n;
 279                 arg++;
 280             }
 281             /* Null terminate the string.  */
 282             *s = 0;
 283             len = s - cmdline_buffer;
 284
 285             /* Unlock the buffer on the ARM side.  */
 286             unlock_user(cmdline_buffer, ARG(0), len);
 287
 288             /* Adjust the commandline length argument.  */
 289             SET_ARG(1, len);
 290
 291             /* Return success if commandline fit into buffer.  */
 292             return *arg ? -1 : 0;
 293         }
 294 #else
 295       return -1;
 296 #endif
 297     case SYS_HEAPINFO:
 298         {
 299             uint32_t *ptr;
 300             uint32_t limit;
 301
 302 #ifdef CONFIG_USER_ONLY
 303             /* Some C libraries assume the heap immediately follows .bss, so
 304                allocate it using sbrk.  */
 305             if (!ts->heap_limit) {
 306                 long ret;
 307
 308                 ts->heap_base = do_brk(0);
 309                 limit = ts->heap_base + ARM_ANGEL_HEAP_SIZE;
 310                 /* Try a big heap, and reduce the size if that fails.  */
 311                 for (;;) {
 312                     ret = do_brk(limit);
 313                     if (ret != -1)
 314                         break;
 315                     limit = (ts->heap_base >> 1) + (limit >> 1);
 316                 }
 317                 ts->heap_limit = limit;
 318             }
 319
 320             ptr = lock_user(ARG(0), 16, 0);
 321             ptr[0] = tswap32(ts->heap_base);
 322             ptr[1] = tswap32(ts->heap_limit);
 323             ptr[2] = tswap32(ts->stack_base);
 324             ptr[3] = tswap32(0); /* Stack limit.  */
 325             unlock_user(ptr, ARG(0), 16);
 326 #else
 327             limit = ram_size;
 328             ptr = lock_user(ARG(0), 16, 0);
 329             /* TODO: Make this use the limit of the loaded application.  */
 330             ptr[0] = tswap32(limit / 2);
 331             ptr[1] = tswap32(limit);
 332             ptr[2] = tswap32(limit); /* Stack base */
 333             ptr[3] = tswap32(0); /* Stack limit.  */
 334             unlock_user(ptr, ARG(0), 16);
 335 #endif
 336             return 0;
 337         }
 338     case SYS_EXIT:
 339         exit(0);
 340     default:
 341         fprintf(stderr, "qemu: Unsupported SemiHosting SWI 0x%02x\n", nr);
 342         cpu_dump_state(env, stderr, fprintf, 0);
 343         abort();
 344     }
 345 }