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
42 #include "arm7_9_common.h"
44 #include "cortex_m3.h"
46 #include "arm_semihosting.h"
47 #include <helper/binarybuffer.h>
48 #include <helper/log.h>
51 static int open_modeflags
[12] = {
56 O_WRONLY
| O_CREAT
| O_TRUNC
,
57 O_WRONLY
| O_CREAT
| O_TRUNC
| O_BINARY
,
58 O_RDWR
| O_CREAT
| O_TRUNC
,
59 O_RDWR
| O_CREAT
| O_TRUNC
| O_BINARY
,
60 O_WRONLY
| O_CREAT
| O_APPEND
,
61 O_WRONLY
| O_CREAT
| O_APPEND
| O_BINARY
,
62 O_RDWR
| O_CREAT
| O_APPEND
,
63 O_RDWR
| O_CREAT
| O_APPEND
| O_BINARY
66 static int do_semihosting(struct target
*target
)
68 struct arm
*arm
= target_to_arm(target
);
69 uint32_t r0
= buf_get_u32(arm
->core_cache
->reg_list
[0].value
, 0, 32);
70 uint32_t r1
= buf_get_u32(arm
->core_cache
->reg_list
[1].value
, 0, 32);
75 if (is_arm7_9(target_to_arm7_9(target
)))
77 lr
= buf_get_u32(ARMV4_5_CORE_REG_MODE(arm
->core_cache
, ARM_MODE_SVC
, 14).value
, 0, 32);
78 spsr
= buf_get_u32(arm
->spsr
->value
, 0, 32);;
82 * TODO: lots of security issues are not considered yet, such as:
83 * - no validation on target provided file descriptors
84 * - no safety checks on opened/deleted/renamed file paths
85 * Beware the target app you use this support with.
87 * TODO: explore mapping requests to GDB's "File-I/O Remote
88 * Protocol Extension" ... when GDB is active.
91 case 0x01: /* SYS_OPEN */
92 retval
= target_read_memory(target
, r1
, 4, 3, params
);
93 if (retval
!= ERROR_OK
)
96 uint32_t a
= target_buffer_get_u32(target
, params
+0);
97 uint32_t m
= target_buffer_get_u32(target
, params
+4);
98 uint32_t l
= target_buffer_get_u32(target
, params
+8);
99 if (l
<= 255 && m
<= 11) {
101 retval
= target_read_memory(target
, a
, 1, l
, fn
);
102 if (retval
!= ERROR_OK
)
105 if (strcmp((char *)fn
, ":tt") == 0) {
107 result
= dup(STDIN_FILENO
);
109 result
= dup(STDOUT_FILENO
);
111 /* cygwin requires the permission setting
112 * otherwise it will fail to reopen a previously
114 result
= open((char *)fn
, open_modeflags
[m
], 0644);
116 arm
->semihosting_errno
= errno
;
119 arm
->semihosting_errno
= EINVAL
;
124 case 0x02: /* SYS_CLOSE */
125 retval
= target_read_memory(target
, r1
, 4, 1, params
);
126 if (retval
!= ERROR_OK
)
129 int fd
= target_buffer_get_u32(target
, params
+0);
131 arm
->semihosting_errno
= errno
;
135 case 0x03: /* SYS_WRITEC */
138 retval
= target_read_memory(target
, r1
, 1, 1, &c
);
139 if (retval
!= ERROR_OK
)
146 case 0x04: /* SYS_WRITE0 */
149 retval
= target_read_memory(target
, r1
, 1, 1, &c
);
150 if (retval
!= ERROR_OK
)
159 case 0x05: /* SYS_WRITE */
160 retval
= target_read_memory(target
, r1
, 4, 3, params
);
161 if (retval
!= ERROR_OK
)
164 int fd
= target_buffer_get_u32(target
, params
+0);
165 uint32_t a
= target_buffer_get_u32(target
, params
+4);
166 size_t l
= target_buffer_get_u32(target
, params
+8);
167 uint8_t *buf
= malloc(l
);
170 arm
->semihosting_errno
= ENOMEM
;
172 retval
= target_read_buffer(target
, a
, l
, buf
);
173 if (retval
!= ERROR_OK
) {
177 result
= write(fd
, buf
, l
);
178 arm
->semihosting_errno
= errno
;
186 case 0x06: /* SYS_READ */
187 retval
= target_read_memory(target
, r1
, 4, 3, params
);
188 if (retval
!= ERROR_OK
)
191 int fd
= target_buffer_get_u32(target
, params
+0);
192 uint32_t a
= target_buffer_get_u32(target
, params
+4);
193 ssize_t l
= target_buffer_get_u32(target
, params
+8);
194 uint8_t *buf
= malloc(l
);
197 arm
->semihosting_errno
= ENOMEM
;
199 result
= read(fd
, buf
, l
);
200 arm
->semihosting_errno
= errno
;
202 retval
= target_write_buffer(target
, a
, result
, buf
);
203 if (retval
!= ERROR_OK
) {
214 case 0x07: /* SYS_READC */
218 case 0x08: /* SYS_ISERROR */
219 retval
= target_read_memory(target
, r1
, 4, 1, params
);
220 if (retval
!= ERROR_OK
)
222 result
= (target_buffer_get_u32(target
, params
+0) != 0);
225 case 0x09: /* SYS_ISTTY */
226 retval
= target_read_memory(target
, r1
, 4, 1, params
);
227 if (retval
!= ERROR_OK
)
229 result
= isatty(target_buffer_get_u32(target
, params
+0));
232 case 0x0a: /* SYS_SEEK */
233 retval
= target_read_memory(target
, r1
, 4, 2, params
);
234 if (retval
!= ERROR_OK
)
237 int fd
= target_buffer_get_u32(target
, params
+0);
238 off_t pos
= target_buffer_get_u32(target
, params
+4);
239 result
= lseek(fd
, pos
, SEEK_SET
);
240 arm
->semihosting_errno
= errno
;
246 case 0x0c: /* SYS_FLEN */
247 retval
= target_read_memory(target
, r1
, 4, 1, params
);
248 if (retval
!= ERROR_OK
)
251 int fd
= target_buffer_get_u32(target
, params
+0);
253 result
= fstat(fd
, &buf
);
255 arm
->semihosting_errno
= errno
;
259 result
= buf
.st_size
;
263 case 0x0e: /* SYS_REMOVE */
264 retval
= target_read_memory(target
, r1
, 4, 2, params
);
265 if (retval
!= ERROR_OK
)
268 uint32_t a
= target_buffer_get_u32(target
, params
+0);
269 uint32_t l
= target_buffer_get_u32(target
, params
+4);
272 retval
= target_read_memory(target
, a
, 1, l
, fn
);
273 if (retval
!= ERROR_OK
)
276 result
= remove((char *)fn
);
277 arm
->semihosting_errno
= errno
;
280 arm
->semihosting_errno
= EINVAL
;
285 case 0x0f: /* SYS_RENAME */
286 retval
= target_read_memory(target
, r1
, 4, 4, params
);
287 if (retval
!= ERROR_OK
)
290 uint32_t a1
= target_buffer_get_u32(target
, params
+0);
291 uint32_t l1
= target_buffer_get_u32(target
, params
+4);
292 uint32_t a2
= target_buffer_get_u32(target
, params
+8);
293 uint32_t l2
= target_buffer_get_u32(target
, params
+12);
294 if (l1
<= 255 && l2
<= 255) {
295 uint8_t fn1
[256], fn2
[256];
296 retval
= target_read_memory(target
, a1
, 1, l1
, fn1
);
297 if (retval
!= ERROR_OK
)
299 retval
= target_read_memory(target
, a2
, 1, l2
, fn2
);
300 if (retval
!= ERROR_OK
)
304 result
= rename((char *)fn1
, (char *)fn2
);
305 arm
->semihosting_errno
= errno
;
308 arm
->semihosting_errno
= EINVAL
;
313 case 0x11: /* SYS_TIME */
317 case 0x13: /* SYS_ERRNO */
318 result
= arm
->semihosting_errno
;
321 case 0x15: /* SYS_GET_CMDLINE */
322 retval
= target_read_memory(target
, r1
, 4, 2, params
);
323 if (retval
!= ERROR_OK
)
326 uint32_t a
= target_buffer_get_u32(target
, params
+0);
327 uint32_t l
= target_buffer_get_u32(target
, params
+4);
328 char *arg
= "foobar";
329 uint32_t s
= strlen(arg
) + 1;
333 retval
= target_write_buffer(target
, a
, s
, (void*)arg
);
334 if (retval
!= ERROR_OK
)
341 case 0x16: /* SYS_HEAPINFO */
342 retval
= target_read_memory(target
, r1
, 4, 1, params
);
343 if (retval
!= ERROR_OK
)
346 uint32_t a
= target_buffer_get_u32(target
, params
+0);
347 /* tell the remote we have no idea */
348 memset(params
, 0, 4*4);
349 retval
= target_write_memory(target
, a
, 4, 4, params
);
350 if (retval
!= ERROR_OK
)
356 case 0x18: /* angel_SWIreason_ReportException */
358 case 0x20026: /* ADP_Stopped_ApplicationExit */
359 fprintf(stderr
, "semihosting: *** application exited ***\n");
361 case 0x20000: /* ADP_Stopped_BranchThroughZero */
362 case 0x20001: /* ADP_Stopped_UndefinedInstr */
363 case 0x20002: /* ADP_Stopped_SoftwareInterrupt */
364 case 0x20003: /* ADP_Stopped_PrefetchAbort */
365 case 0x20004: /* ADP_Stopped_DataAbort */
366 case 0x20005: /* ADP_Stopped_AddressException */
367 case 0x20006: /* ADP_Stopped_IRQ */
368 case 0x20007: /* ADP_Stopped_FIQ */
369 case 0x20020: /* ADP_Stopped_BreakPoint */
370 case 0x20021: /* ADP_Stopped_WatchPoint */
371 case 0x20022: /* ADP_Stopped_StepComplete */
372 case 0x20023: /* ADP_Stopped_RunTimeErrorUnknown */
373 case 0x20024: /* ADP_Stopped_InternalError */
374 case 0x20025: /* ADP_Stopped_UserInterruption */
375 case 0x20027: /* ADP_Stopped_StackOverflow */
376 case 0x20028: /* ADP_Stopped_DivisionByZero */
377 case 0x20029: /* ADP_Stopped_OSSpecific */
379 fprintf(stderr
, "semihosting: exception %#x\n",
382 return target_call_event_callbacks(target
, TARGET_EVENT_HALTED
);
384 case 0x0d: /* SYS_TMPNAM */
385 case 0x10: /* SYS_CLOCK */
386 case 0x12: /* SYS_SYSTEM */
387 case 0x17: /* angel_SWIreason_EnterSVC */
388 case 0x30: /* SYS_ELAPSED */
389 case 0x31: /* SYS_TICKFREQ */
391 fprintf(stderr
, "semihosting: unsupported call %#x\n",
394 arm
->semihosting_errno
= ENOTSUP
;
397 /* resume execution to the original mode */
399 if (is_arm7_9(target_to_arm7_9(target
)))
401 /* return value in R0 */
402 buf_set_u32(arm
->core_cache
->reg_list
[0].value
, 0, 32, result
);
403 arm
->core_cache
->reg_list
[0].dirty
= 1;
406 buf_set_u32(arm
->core_cache
->reg_list
[15].value
, 0, 32, lr
);
407 arm
->core_cache
->reg_list
[15].dirty
= 1;
409 /* saved PSR --> current PSR */
410 buf_set_u32(arm
->cpsr
->value
, 0, 32, spsr
);
411 arm
->cpsr
->dirty
= 1;
412 arm
->core_mode
= spsr
& 0x1f;
414 arm
->core_state
= ARM_STATE_THUMB
;
418 /* resume execution, this will be pc+2 to skip over the
419 * bkpt instruction */
421 /* return result in R0 */
422 buf_set_u32(arm
->core_cache
->reg_list
[0].value
, 0, 32, result
);
423 arm
->core_cache
->reg_list
[0].dirty
= 1;
426 return target_resume(target
, 1, 0, 0, 0);
430 * Checks for and processes an ARM semihosting request. This is meant
431 * to be called when the target is stopped due to a debug mode entry.
432 * If the value 0 is returned then there was nothing to process. A non-zero
433 * return value signifies that a request was processed and the target resumed,
434 * or an error was encountered, in which case the caller must return
437 * @param target Pointer to the ARM target to process. This target must
438 * not represent an ARMv6-M or ARMv7-M processor.
439 * @param retval Pointer to a location where the return code will be stored
440 * @return non-zero value if a request was processed or an error encountered
442 int arm_semihosting(struct target
*target
, int *retval
)
444 struct arm
*arm
= target_to_arm(target
);
445 uint32_t pc
, lr
, spsr
;
448 if (!arm
->is_semihosting
)
451 if (is_arm7_9(target_to_arm7_9(target
)))
453 if (arm
->core_mode
!= ARM_MODE_SVC
)
456 /* Check for PC == 0x00000008 or 0xffff0008: Supervisor Call vector. */
458 pc
= buf_get_u32(r
->value
, 0, 32);
459 if (pc
!= 0x00000008 && pc
!= 0xffff0008)
462 r
= arm_reg_current(arm
, 14);
463 lr
= buf_get_u32(r
->value
, 0, 32);
465 /* Core-specific code should make sure SPSR is retrieved
466 * when the above checks pass...
468 if (!arm
->spsr
->valid
) {
469 LOG_ERROR("SPSR not valid!");
470 *retval
= ERROR_FAIL
;
474 spsr
= buf_get_u32(arm
->spsr
->value
, 0, 32);
476 /* check instruction that triggered this trap */
477 if (spsr
& (1 << 5)) {
478 /* was in Thumb (or ThumbEE) mode */
482 *retval
= target_read_memory(target
, lr
-2, 2, 1, insn_buf
);
483 if (*retval
!= ERROR_OK
)
485 insn
= target_buffer_get_u16(target
, insn_buf
);
490 } else if (spsr
& (1 << 24)) {
491 /* was in Jazelle mode */
494 /* was in ARM mode */
498 *retval
= target_read_memory(target
, lr
-4, 4, 1, insn_buf
);
499 if (*retval
!= ERROR_OK
)
501 insn
= target_buffer_get_u32(target
, insn_buf
);
504 if (insn
!= 0xEF123456)
508 else if (is_armv7m(target_to_armv7m(target
)))
512 if (target
->debug_reason
!= DBG_REASON_BREAKPOINT
)
516 pc
= buf_get_u32(r
->value
, 0, 32);
519 *retval
= target_read_u16(target
, pc
, &insn
);
520 if (*retval
!= ERROR_OK
)
529 LOG_ERROR("Unsupported semi-hosting Target");
533 *retval
= do_semihosting(target
);