1 /***************************************************************************
2 * Copyright (C) 2009 by Marvell Technology Group Ltd. *
3 * Written by Nicolas Pitre <nico@marvell.com> *
5 * Copyright (C) 2010 by Spencer Oliver *
6 * spen@spen-soft.co.uk *
8 * This program is free software; you can redistribute it and/or modify *
9 * it under the terms of the GNU General Public License as published by *
10 * the Free Software Foundation; either version 2 of the License, or *
11 * (at your option) any later version. *
13 * This program is distributed in the hope that it will be useful, *
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of *
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
16 * GNU General Public License for more details. *
18 * You should have received a copy of the GNU General Public License *
19 * along with this program; if not, write to the *
20 * Free Software Foundation, Inc., *
21 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
22 ***************************************************************************/
26 * Hold ARM semihosting support.
28 * Semihosting enables code running on an ARM target to use the I/O
29 * facilities on the host computer. The target application must be linked
30 * against a library that forwards operation requests by using the SVC
31 * instruction trapped at the Supervisor Call vector by the debugger.
32 * Details can be found in chapter 8 of DUI0203I_rvct_developer_guide.pdf
43 #include "arm_semihosting.h"
44 #include <helper/binarybuffer.h>
45 #include <helper/log.h>
47 static int open_modeflags
[12] = {
52 O_WRONLY
| O_CREAT
| O_TRUNC
,
53 O_WRONLY
| O_CREAT
| O_TRUNC
| O_BINARY
,
54 O_RDWR
| O_CREAT
| O_TRUNC
,
55 O_RDWR
| O_CREAT
| O_TRUNC
| O_BINARY
,
56 O_WRONLY
| O_CREAT
| O_APPEND
,
57 O_WRONLY
| O_CREAT
| O_APPEND
| O_BINARY
,
58 O_RDWR
| O_CREAT
| O_APPEND
,
59 O_RDWR
| O_CREAT
| O_APPEND
| O_BINARY
62 static int do_semihosting(struct target
*target
)
64 struct arm
*armv4_5
= target_to_arm(target
);
65 uint32_t r0
= buf_get_u32(armv4_5
->core_cache
->reg_list
[0].value
, 0, 32);
66 uint32_t r1
= buf_get_u32(armv4_5
->core_cache
->reg_list
[1].value
, 0, 32);
67 uint32_t lr
= buf_get_u32(ARMV4_5_CORE_REG_MODE(armv4_5
->core_cache
, ARM_MODE_SVC
, 14).value
, 0, 32);
68 uint32_t spsr
= buf_get_u32(armv4_5
->spsr
->value
, 0, 32);;
73 * TODO: lots of security issues are not considered yet, such as:
74 * - no validation on target provided file descriptors
75 * - no safety checks on opened/deleted/renamed file paths
76 * Beware the target app you use this support with.
78 * TODO: explore mapping requests to GDB's "File-I/O Remote
79 * Protocol Extension" ... when GDB is active.
82 case 0x01: /* SYS_OPEN */
83 retval
= target_read_memory(target
, r1
, 4, 3, params
);
84 if (retval
!= ERROR_OK
)
87 uint32_t a
= target_buffer_get_u32(target
, params
+0);
88 uint32_t m
= target_buffer_get_u32(target
, params
+4);
89 uint32_t l
= target_buffer_get_u32(target
, params
+8);
90 if (l
<= 255 && m
<= 11) {
92 retval
= target_read_memory(target
, a
, 1, l
, fn
);
93 if (retval
!= ERROR_OK
)
96 if (strcmp((char *)fn
, ":tt") == 0) {
98 result
= dup(STDIN_FILENO
);
100 result
= dup(STDOUT_FILENO
);
102 /* cygwin requires the permission setting
103 * otherwise it will fail to reopen a previously
105 result
= open((char *)fn
, open_modeflags
[m
], 0644);
107 armv4_5
->semihosting_errno
= errno
;
110 armv4_5
->semihosting_errno
= EINVAL
;
115 case 0x02: /* SYS_CLOSE */
116 retval
= target_read_memory(target
, r1
, 4, 1, params
);
117 if (retval
!= ERROR_OK
)
120 int fd
= target_buffer_get_u32(target
, params
+0);
122 armv4_5
->semihosting_errno
= errno
;
126 case 0x03: /* SYS_WRITEC */
129 retval
= target_read_memory(target
, r1
, 1, 1, &c
);
130 if (retval
!= ERROR_OK
)
137 case 0x04: /* SYS_WRITE0 */
140 retval
= target_read_memory(target
, r1
, 1, 1, &c
);
141 if (retval
!= ERROR_OK
)
150 case 0x05: /* SYS_WRITE */
151 retval
= target_read_memory(target
, r1
, 4, 3, params
);
152 if (retval
!= ERROR_OK
)
155 int fd
= target_buffer_get_u32(target
, params
+0);
156 uint32_t a
= target_buffer_get_u32(target
, params
+4);
157 size_t l
= target_buffer_get_u32(target
, params
+8);
158 uint8_t *buf
= malloc(l
);
161 armv4_5
->semihosting_errno
= ENOMEM
;
163 retval
= target_read_buffer(target
, a
, l
, buf
);
164 if (retval
!= ERROR_OK
) {
168 result
= write(fd
, buf
, l
);
169 armv4_5
->semihosting_errno
= errno
;
177 case 0x06: /* SYS_READ */
178 retval
= target_read_memory(target
, r1
, 4, 3, params
);
179 if (retval
!= ERROR_OK
)
182 int fd
= target_buffer_get_u32(target
, params
+0);
183 uint32_t a
= target_buffer_get_u32(target
, params
+4);
184 ssize_t l
= target_buffer_get_u32(target
, params
+8);
185 uint8_t *buf
= malloc(l
);
188 armv4_5
->semihosting_errno
= ENOMEM
;
190 result
= read(fd
, buf
, l
);
191 armv4_5
->semihosting_errno
= errno
;
193 retval
= target_write_buffer(target
, a
, result
, buf
);
194 if (retval
!= ERROR_OK
) {
205 case 0x07: /* SYS_READC */
209 case 0x08: /* SYS_ISERROR */
210 retval
= target_read_memory(target
, r1
, 4, 1, params
);
211 if (retval
!= ERROR_OK
)
213 result
= (target_buffer_get_u32(target
, params
+0) != 0);
216 case 0x09: /* SYS_ISTTY */
217 retval
= target_read_memory(target
, r1
, 4, 1, params
);
218 if (retval
!= ERROR_OK
)
220 result
= isatty(target_buffer_get_u32(target
, params
+0));
223 case 0x0a: /* SYS_SEEK */
224 retval
= target_read_memory(target
, r1
, 4, 2, params
);
225 if (retval
!= ERROR_OK
)
228 int fd
= target_buffer_get_u32(target
, params
+0);
229 off_t pos
= target_buffer_get_u32(target
, params
+4);
230 result
= lseek(fd
, pos
, SEEK_SET
);
231 armv4_5
->semihosting_errno
= errno
;
237 case 0x0c: /* SYS_FLEN */
238 retval
= target_read_memory(target
, r1
, 4, 1, params
);
239 if (retval
!= ERROR_OK
)
242 int fd
= target_buffer_get_u32(target
, params
+0);
244 result
= fstat(fd
, &buf
);
246 armv4_5
->semihosting_errno
= errno
;
250 result
= buf
.st_size
;
254 case 0x0e: /* SYS_REMOVE */
255 retval
= target_read_memory(target
, r1
, 4, 2, params
);
256 if (retval
!= ERROR_OK
)
259 uint32_t a
= target_buffer_get_u32(target
, params
+0);
260 uint32_t l
= target_buffer_get_u32(target
, params
+4);
263 retval
= target_read_memory(target
, a
, 1, l
, fn
);
264 if (retval
!= ERROR_OK
)
267 result
= remove((char *)fn
);
268 armv4_5
->semihosting_errno
= errno
;
271 armv4_5
->semihosting_errno
= EINVAL
;
276 case 0x0f: /* SYS_RENAME */
277 retval
= target_read_memory(target
, r1
, 4, 4, params
);
278 if (retval
!= ERROR_OK
)
281 uint32_t a1
= target_buffer_get_u32(target
, params
+0);
282 uint32_t l1
= target_buffer_get_u32(target
, params
+4);
283 uint32_t a2
= target_buffer_get_u32(target
, params
+8);
284 uint32_t l2
= target_buffer_get_u32(target
, params
+12);
285 if (l1
<= 255 && l2
<= 255) {
286 uint8_t fn1
[256], fn2
[256];
287 retval
= target_read_memory(target
, a1
, 1, l1
, fn1
);
288 if (retval
!= ERROR_OK
)
290 retval
= target_read_memory(target
, a2
, 1, l2
, fn2
);
291 if (retval
!= ERROR_OK
)
295 result
= rename((char *)fn1
, (char *)fn2
);
296 armv4_5
->semihosting_errno
= errno
;
299 armv4_5
->semihosting_errno
= EINVAL
;
304 case 0x11: /* SYS_TIME */
308 case 0x13: /* SYS_ERRNO */
309 result
= armv4_5
->semihosting_errno
;
312 case 0x15: /* SYS_GET_CMDLINE */
313 retval
= target_read_memory(target
, r1
, 4, 2, params
);
314 if (retval
!= ERROR_OK
)
317 uint32_t a
= target_buffer_get_u32(target
, params
+0);
318 uint32_t l
= target_buffer_get_u32(target
, params
+4);
319 char *arg
= "foobar";
320 uint32_t s
= strlen(arg
) + 1;
324 retval
= target_write_buffer(target
, a
, s
, (void*)arg
);
325 if (retval
!= ERROR_OK
)
332 case 0x16: /* SYS_HEAPINFO */
333 retval
= target_read_memory(target
, r1
, 4, 1, params
);
334 if (retval
!= ERROR_OK
)
337 uint32_t a
= target_buffer_get_u32(target
, params
+0);
338 /* tell the remote we have no idea */
339 memset(params
, 0, 4*4);
340 retval
= target_write_memory(target
, a
, 4, 4, params
);
341 if (retval
!= ERROR_OK
)
347 case 0x18: /* angel_SWIreason_ReportException */
349 case 0x20026: /* ADP_Stopped_ApplicationExit */
350 fprintf(stderr
, "semihosting: *** application exited ***\n");
352 case 0x20000: /* ADP_Stopped_BranchThroughZero */
353 case 0x20001: /* ADP_Stopped_UndefinedInstr */
354 case 0x20002: /* ADP_Stopped_SoftwareInterrupt */
355 case 0x20003: /* ADP_Stopped_PrefetchAbort */
356 case 0x20004: /* ADP_Stopped_DataAbort */
357 case 0x20005: /* ADP_Stopped_AddressException */
358 case 0x20006: /* ADP_Stopped_IRQ */
359 case 0x20007: /* ADP_Stopped_FIQ */
360 case 0x20020: /* ADP_Stopped_BreakPoint */
361 case 0x20021: /* ADP_Stopped_WatchPoint */
362 case 0x20022: /* ADP_Stopped_StepComplete */
363 case 0x20023: /* ADP_Stopped_RunTimeErrorUnknown */
364 case 0x20024: /* ADP_Stopped_InternalError */
365 case 0x20025: /* ADP_Stopped_UserInterruption */
366 case 0x20027: /* ADP_Stopped_StackOverflow */
367 case 0x20028: /* ADP_Stopped_DivisionByZero */
368 case 0x20029: /* ADP_Stopped_OSSpecific */
370 fprintf(stderr
, "semihosting: exception %#x\n",
373 return target_call_event_callbacks(target
, TARGET_EVENT_HALTED
);
375 case 0x0d: /* SYS_TMPNAM */
376 case 0x10: /* SYS_CLOCK */
377 case 0x12: /* SYS_SYSTEM */
378 case 0x17: /* angel_SWIreason_EnterSVC */
379 case 0x30: /* SYS_ELAPSED */
380 case 0x31: /* SYS_TICKFREQ */
382 fprintf(stderr
, "semihosting: unsupported call %#x\n",
385 armv4_5
->semihosting_errno
= ENOTSUP
;
388 /* resume execution to the original mode */
390 /* return value in R0 */
391 buf_set_u32(armv4_5
->core_cache
->reg_list
[0].value
, 0, 32, result
);
392 armv4_5
->core_cache
->reg_list
[0].dirty
= 1;
395 buf_set_u32(armv4_5
->core_cache
->reg_list
[15].value
, 0, 32, lr
);
396 armv4_5
->core_cache
->reg_list
[15].dirty
= 1;
398 /* saved PSR --> current PSR */
399 buf_set_u32(armv4_5
->cpsr
->value
, 0, 32, spsr
);
400 armv4_5
->cpsr
->dirty
= 1;
401 armv4_5
->core_mode
= spsr
& 0x1f;
403 armv4_5
->core_state
= ARM_STATE_THUMB
;
405 return target_resume(target
, 1, 0, 0, 0);
409 * Checks for and processes an ARM semihosting request. This is meant
410 * to be called when the target is stopped due to a debug mode entry.
411 * If the value 0 is returned then there was nothing to process. A non-zero
412 * return value signifies that a request was processed and the target resumed,
413 * or an error was encountered, in which case the caller must return
416 * @param target Pointer to the ARM target to process. This target must
417 * not represent an ARMv6-M or ARMv7-M processor.
418 * @param retval Pointer to a location where the return code will be stored
419 * @return non-zero value if a request was processed or an error encountered
421 int arm_semihosting(struct target
*target
, int *retval
)
423 struct arm
*arm
= target_to_arm(target
);
424 uint32_t pc
, lr
, spsr
;
427 if (!arm
->is_semihosting
|| arm
->core_mode
!= ARM_MODE_SVC
)
430 /* Check for PC == 0x00000008 or 0xffff0008: Supervisor Call vector. */
431 r
= arm
->core_cache
->reg_list
+ 15;
432 pc
= buf_get_u32(r
->value
, 0, 32);
433 if (pc
!= 0x00000008 && pc
!= 0xffff0008)
436 r
= arm_reg_current(arm
, 14);
437 lr
= buf_get_u32(r
->value
, 0, 32);
439 /* Core-specific code should make sure SPSR is retrieved
440 * when the above checks pass...
442 if (!arm
->spsr
->valid
) {
443 LOG_ERROR("SPSR not valid!");
444 *retval
= ERROR_FAIL
;
448 spsr
= buf_get_u32(arm
->spsr
->value
, 0, 32);
450 /* check instruction that triggered this trap */
451 if (spsr
& (1 << 5)) {
452 /* was in Thumb (or ThumbEE) mode */
456 *retval
= target_read_memory(target
, lr
-2, 2, 1, insn_buf
);
457 if (*retval
!= ERROR_OK
)
459 insn
= target_buffer_get_u16(target
, insn_buf
);
464 } else if (spsr
& (1 << 24)) {
465 /* was in Jazelle mode */
468 /* was in ARM mode */
472 *retval
= target_read_memory(target
, lr
-4, 4, 1, insn_buf
);
473 if (*retval
!= ERROR_OK
)
475 insn
= target_buffer_get_u32(target
, insn_buf
);
478 if (insn
!= 0xEF123456)
482 *retval
= do_semihosting(target
);