target/m68k/m68k-semi.c

   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 #include "semihosting/syscalls.h"
  25 #include "semihosting/softmmu-uaccess.h"
  26 #include "hw/boards.h"
  27 #include "qemu/log.h"
  28
  29 #define HOSTED_EXIT  0
  30 #define HOSTED_INIT_SIM 1
  31 #define HOSTED_OPEN 2
  32 #define HOSTED_CLOSE 3
  33 #define HOSTED_READ 4
  34 #define HOSTED_WRITE 5
  35 #define HOSTED_LSEEK 6
  36 #define HOSTED_RENAME 7
  37 #define HOSTED_UNLINK 8
  38 #define HOSTED_STAT 9
  39 #define HOSTED_FSTAT 10
  40 #define HOSTED_GETTIMEOFDAY 11
  41 #define HOSTED_ISATTY 12
  42 #define HOSTED_SYSTEM 13
  43
  44 static int host_to_gdb_errno(int err)
  45 {
  46 #define E(X)  case E##X: return GDB_E##X
  47     switch (err) {
  48     E(PERM);
  49     E(NOENT);
  50     E(INTR);
  51     E(BADF);
  52     E(ACCES);
  53     E(FAULT);
  54     E(BUSY);
  55     E(EXIST);
  56     E(NODEV);
  57     E(NOTDIR);
  58     E(ISDIR);
  59     E(INVAL);
  60     E(NFILE);
  61     E(MFILE);
  62     E(FBIG);
  63     E(NOSPC);
  64     E(SPIPE);
  65     E(ROFS);
  66     E(NAMETOOLONG);
  67     default:
  68         return GDB_EUNKNOWN;
  69     }
  70 #undef E
  71 }
  72
  73 static void m68k_semi_u32_cb(CPUState *cs, uint64_t ret, int err)
  74 {
  75     M68kCPU *cpu = M68K_CPU(cs);
  76     CPUM68KState *env = &cpu->env;
  77
  78     target_ulong args = env->dregs[1];
  79     if (put_user_u32(ret, args) ||
  80         put_user_u32(host_to_gdb_errno(err), args + 4)) {
  81         /*
  82          * The m68k semihosting ABI does not provide any way to report this
  83          * error to the guest, so the best we can do is log it in qemu.
  84          * It is always a guest error not to pass us a valid argument block.
  85          */
  86         qemu_log_mask(LOG_GUEST_ERROR, "m68k-semihosting: return value "
  87                       "discarded because argument block not writable\n");
  88     }
  89 }
  90
  91 static void m68k_semi_u64_cb(CPUState *cs, uint64_t ret, int err)
  92 {
  93     M68kCPU *cpu = M68K_CPU(cs);
  94     CPUM68KState *env = &cpu->env;
  95
  96     target_ulong args = env->dregs[1];
  97     if (put_user_u32(ret >> 32, args) ||
  98         put_user_u32(ret, args + 4) ||
  99         put_user_u32(host_to_gdb_errno(err), args + 8)) {
 100         /* No way to report this via m68k semihosting ABI; just log it */
 101         qemu_log_mask(LOG_GUEST_ERROR, "m68k-semihosting: return value "
 102                       "discarded because argument block not writable\n");
 103     }
 104 }
 105
 106 /*
 107  * Read the input value from the argument block; fail the semihosting
 108  * call if the memory read fails.
 109  */
 110 #define GET_ARG(n) do {                                 \
 111     if (get_user_ual(arg ## n, args + (n) * 4)) {       \
 112         goto failed;                                    \
 113     }                                                   \
 114 } while (0)
 115
 116 #define GET_ARG64(n) do {                               \
 117     if (get_user_ual(arg ## n, args + (n) * 4)) {       \
 118         goto failed64;                                  \
 119     }                                                   \
 120 } while (0)
 121
 122
 123 void do_m68k_semihosting(CPUM68KState *env, int nr)
 124 {
 125     CPUState *cs = env_cpu(env);
 126     uint32_t args;
 127     target_ulong arg0, arg1, arg2, arg3;
 128
 129     args = env->dregs[1];
 130     switch (nr) {
 131     case HOSTED_EXIT:
 132         gdb_exit(env->dregs[0]);
 133         exit(env->dregs[0]);
 134
 135     case HOSTED_OPEN:
 136         GET_ARG(0);
 137         GET_ARG(1);
 138         GET_ARG(2);
 139         GET_ARG(3);
 140         semihost_sys_open(cs, m68k_semi_u32_cb, arg0, arg1, arg2, arg3);
 141         break;
 142
 143     case HOSTED_CLOSE:
 144         GET_ARG(0);
 145         semihost_sys_close(cs, m68k_semi_u32_cb, arg0);
 146         break;
 147
 148     case HOSTED_READ:
 149         GET_ARG(0);
 150         GET_ARG(1);
 151         GET_ARG(2);
 152         semihost_sys_read(cs, m68k_semi_u32_cb, arg0, arg1, arg2);
 153         break;
 154
 155     case HOSTED_WRITE:
 156         GET_ARG(0);
 157         GET_ARG(1);
 158         GET_ARG(2);
 159         semihost_sys_write(cs, m68k_semi_u32_cb, arg0, arg1, arg2);
 160         break;
 161
 162     case HOSTED_LSEEK:
 163         GET_ARG64(0);
 164         GET_ARG64(1);
 165         GET_ARG64(2);
 166         GET_ARG64(3);
 167         semihost_sys_lseek(cs, m68k_semi_u64_cb, arg0,
 168                            deposit64(arg2, arg1, 32, 32), arg3);
 169         break;
 170
 171     case HOSTED_RENAME:
 172         GET_ARG(0);
 173         GET_ARG(1);
 174         GET_ARG(2);
 175         GET_ARG(3);
 176         semihost_sys_rename(cs, m68k_semi_u32_cb, arg0, arg1, arg2, arg3);
 177         break;
 178
 179     case HOSTED_UNLINK:
 180         GET_ARG(0);
 181         GET_ARG(1);
 182         semihost_sys_remove(cs, m68k_semi_u32_cb, arg0, arg1);
 183         break;
 184
 185     case HOSTED_STAT:
 186         GET_ARG(0);
 187         GET_ARG(1);
 188         GET_ARG(2);
 189         semihost_sys_stat(cs, m68k_semi_u32_cb, arg0, arg1, arg2);
 190         break;
 191
 192     case HOSTED_FSTAT:
 193         GET_ARG(0);
 194         GET_ARG(1);
 195         semihost_sys_fstat(cs, m68k_semi_u32_cb, arg0, arg1);
 196         break;
 197
 198     case HOSTED_GETTIMEOFDAY:
 199         GET_ARG(0);
 200         GET_ARG(1);
 201         semihost_sys_gettimeofday(cs, m68k_semi_u32_cb, arg0, arg1);
 202         break;
 203
 204     case HOSTED_ISATTY:
 205         GET_ARG(0);
 206         semihost_sys_isatty(cs, m68k_semi_u32_cb, arg0);
 207         break;
 208
 209     case HOSTED_SYSTEM:
 210         GET_ARG(0);
 211         GET_ARG(1);
 212         semihost_sys_system(cs, m68k_semi_u32_cb, arg0, arg1);
 213         break;
 214
 215     case HOSTED_INIT_SIM:
 216         /*
 217          * FIXME: This is wrong for boards where RAM does not start at
 218          * address zero.
 219          */
 220         env->dregs[1] = current_machine->ram_size;
 221         env->aregs[7] = current_machine->ram_size;
 222         return;
 223
 224     default:
 225         cpu_abort(env_cpu(env), "Unsupported semihosting syscall %d\n", nr);
 226
 227     failed:
 228         m68k_semi_u32_cb(cs, -1, EFAULT);
 229         break;
 230     failed64:
 231         m68k_semi_u64_cb(cs, -1, EFAULT);
 232         break;
 233     }
 234 }