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 * The semihosting protocol implemented here is described in the
20 * libgloss sources:
21 * https://sourceware.org/git/?p=newlib-cygwin.git;a=blob;f=libgloss/m68k/m68k-semi.txt;hb=HEAD
22 */
23
24 #include "qemu/osdep.h"
25
26 #include "cpu.h"
27 #include "gdbstub/syscalls.h"
28 #include "gdbstub/helpers.h"
29 #include "semihosting/syscalls.h"
30 #include "semihosting/uaccess.h"
31 #include "hw/boards.h"
32 #include "qemu/log.h"
33
34 #define HOSTED_EXIT 0
35 #define HOSTED_INIT_SIM 1
36 #define HOSTED_OPEN 2
37 #define HOSTED_CLOSE 3
38 #define HOSTED_READ 4
39 #define HOSTED_WRITE 5
40 #define HOSTED_LSEEK 6
41 #define HOSTED_RENAME 7
42 #define HOSTED_UNLINK 8
43 #define HOSTED_STAT 9
44 #define HOSTED_FSTAT 10
45 #define HOSTED_GETTIMEOFDAY 11
46 #define HOSTED_ISATTY 12
47 #define HOSTED_SYSTEM 13
48
host_to_gdb_errno(int err)49 static int host_to_gdb_errno(int err)
50 {
51 #define E(X) case E##X: return GDB_E##X
52 switch (err) {
53 E(PERM);
54 E(NOENT);
55 E(INTR);
56 E(BADF);
57 E(ACCES);
58 E(FAULT);
59 E(BUSY);
60 E(EXIST);
61 E(NODEV);
62 E(NOTDIR);
63 E(ISDIR);
64 E(INVAL);
65 E(NFILE);
66 E(MFILE);
67 E(FBIG);
68 E(NOSPC);
69 E(SPIPE);
70 E(ROFS);
71 E(NAMETOOLONG);
72 default:
73 return GDB_EUNKNOWN;
74 }
75 #undef E
76 }
77
m68k_semi_u32_cb(CPUState * cs,uint64_t ret,int err)78 static void m68k_semi_u32_cb(CPUState *cs, uint64_t ret, int err)
79 {
80 CPUM68KState *env = cpu_env(cs);
81
82 target_ulong args = env->dregs[1];
83 if (put_user_u32(ret, args) ||
84 put_user_u32(host_to_gdb_errno(err), args + 4)) {
85 /*
86 * The m68k semihosting ABI does not provide any way to report this
87 * error to the guest, so the best we can do is log it in qemu.
88 * It is always a guest error not to pass us a valid argument block.
89 */
90 qemu_log_mask(LOG_GUEST_ERROR, "m68k-semihosting: return value "
91 "discarded because argument block not writable\n");
92 }
93 }
94
m68k_semi_u64_cb(CPUState * cs,uint64_t ret,int err)95 static void m68k_semi_u64_cb(CPUState *cs, uint64_t ret, int err)
96 {
97 CPUM68KState *env = cpu_env(cs);
98
99 target_ulong args = env->dregs[1];
100 if (put_user_u32(ret >> 32, args) ||
101 put_user_u32(ret, args + 4) ||
102 put_user_u32(host_to_gdb_errno(err), args + 8)) {
103 /* No way to report this via m68k semihosting ABI; just log it */
104 qemu_log_mask(LOG_GUEST_ERROR, "m68k-semihosting: return value "
105 "discarded because argument block not writable\n");
106 }
107 }
108
109 /*
110 * Read the input value from the argument block; fail the semihosting
111 * call if the memory read fails.
112 */
113 #define GET_ARG(n) do { \
114 if (get_user_ual(arg ## n, args + (n) * 4)) { \
115 goto failed; \
116 } \
117 } while (0)
118
119 #define GET_ARG64(n) do { \
120 if (get_user_ual(arg ## n, args + (n) * 4)) { \
121 goto failed64; \
122 } \
123 } while (0)
124
125
do_m68k_semihosting(CPUM68KState * env,int nr)126 void do_m68k_semihosting(CPUM68KState *env, int nr)
127 {
128 CPUState *cs = env_cpu(env);
129 uint32_t args;
130 target_ulong arg0, arg1, arg2, arg3;
131
132 args = env->dregs[1];
133 switch (nr) {
134 case HOSTED_EXIT:
135 gdb_exit(env->dregs[1]);
136 exit(env->dregs[1]);
137
138 case HOSTED_OPEN:
139 GET_ARG(0);
140 GET_ARG(1);
141 GET_ARG(2);
142 GET_ARG(3);
143 semihost_sys_open(cs, m68k_semi_u32_cb, arg0, arg1, arg2, arg3);
144 break;
145
146 case HOSTED_CLOSE:
147 GET_ARG(0);
148 semihost_sys_close(cs, m68k_semi_u32_cb, arg0);
149 break;
150
151 case HOSTED_READ:
152 GET_ARG(0);
153 GET_ARG(1);
154 GET_ARG(2);
155 semihost_sys_read(cs, m68k_semi_u32_cb, arg0, arg1, arg2);
156 break;
157
158 case HOSTED_WRITE:
159 GET_ARG(0);
160 GET_ARG(1);
161 GET_ARG(2);
162 semihost_sys_write(cs, m68k_semi_u32_cb, arg0, arg1, arg2);
163 break;
164
165 case HOSTED_LSEEK:
166 GET_ARG64(0);
167 GET_ARG64(1);
168 GET_ARG64(2);
169 GET_ARG64(3);
170 semihost_sys_lseek(cs, m68k_semi_u64_cb, arg0,
171 deposit64(arg2, 32, 32, arg1), arg3);
172 break;
173
174 case HOSTED_RENAME:
175 GET_ARG(0);
176 GET_ARG(1);
177 GET_ARG(2);
178 GET_ARG(3);
179 semihost_sys_rename(cs, m68k_semi_u32_cb, arg0, arg1, arg2, arg3);
180 break;
181
182 case HOSTED_UNLINK:
183 GET_ARG(0);
184 GET_ARG(1);
185 semihost_sys_remove(cs, m68k_semi_u32_cb, arg0, arg1);
186 break;
187
188 case HOSTED_STAT:
189 GET_ARG(0);
190 GET_ARG(1);
191 GET_ARG(2);
192 semihost_sys_stat(cs, m68k_semi_u32_cb, arg0, arg1, arg2);
193 break;
194
195 case HOSTED_FSTAT:
196 GET_ARG(0);
197 GET_ARG(1);
198 semihost_sys_fstat(cs, m68k_semi_u32_cb, arg0, arg1);
199 break;
200
201 case HOSTED_GETTIMEOFDAY:
202 GET_ARG(0);
203 GET_ARG(1);
204 semihost_sys_gettimeofday(cs, m68k_semi_u32_cb, arg0, arg1);
205 break;
206
207 case HOSTED_ISATTY:
208 GET_ARG(0);
209 semihost_sys_isatty(cs, m68k_semi_u32_cb, arg0);
210 break;
211
212 case HOSTED_SYSTEM:
213 GET_ARG(0);
214 GET_ARG(1);
215 semihost_sys_system(cs, m68k_semi_u32_cb, arg0, arg1);
216 break;
217
218 case HOSTED_INIT_SIM:
219 /*
220 * FIXME: This is wrong for boards where RAM does not start at
221 * address zero.
222 */
223 env->dregs[1] = current_machine->ram_size;
224 env->aregs[7] = current_machine->ram_size;
225 return;
226
227 default:
228 cpu_abort(env_cpu(env), "Unsupported semihosting syscall %d\n", nr);
229
230 failed:
231 m68k_semi_u32_cb(cs, -1, EFAULT);
232 break;
233 failed64:
234 m68k_semi_u64_cb(cs, -1, EFAULT);
235 break;
236 }
237 }
238