cb1ac0dc70ea84304a943f5b587c46268a373105
[deliverable/binutils-gdb.git] / gdb / gdbserver / spu-low.c
1 /* Low level interface to SPUs, for the remote server for GDB.
2 Copyright (C) 2006-2014 Free Software Foundation, Inc.
3
4 Contributed by Ulrich Weigand <uweigand@de.ibm.com>.
5
6 This file is part of GDB.
7
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 3 of the License, or
11 (at your option) any later version.
12
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.
17
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20
21 #include "server.h"
22
23 #include "gdb_wait.h"
24 #include <sys/ptrace.h>
25 #include <fcntl.h>
26 #include <unistd.h>
27 #include <errno.h>
28 #include <sys/syscall.h>
29 #include "filestuff.h"
30 #include "hostio.h"
31
32 /* Some older glibc versions do not define this. */
33 #ifndef __WNOTHREAD
34 #define __WNOTHREAD 0x20000000 /* Don't wait on children of other
35 threads in this group */
36 #endif
37
38 #define PTRACE_TYPE_RET long
39 #define PTRACE_TYPE_ARG3 long
40
41 /* Number of registers. */
42 #define SPU_NUM_REGS 130
43 #define SPU_NUM_CORE_REGS 128
44
45 /* Special registers. */
46 #define SPU_ID_REGNUM 128
47 #define SPU_PC_REGNUM 129
48
49 /* PPU side system calls. */
50 #define INSTR_SC 0x44000002
51 #define NR_spu_run 0x0116
52
53 /* These are used in remote-utils.c. */
54 int using_threads = 0;
55
56 /* Defined in auto-generated file reg-spu.c. */
57 void init_registers_spu (void);
58 extern const struct target_desc *tdesc_spu;
59
60 /* Fetch PPU register REGNO. */
61 static CORE_ADDR
62 fetch_ppc_register (int regno)
63 {
64 PTRACE_TYPE_RET res;
65
66 int tid = ptid_get_lwp (current_ptid);
67
68 #ifndef __powerpc64__
69 /* If running as a 32-bit process on a 64-bit system, we attempt
70 to get the full 64-bit register content of the target process.
71 If the PPC special ptrace call fails, we're on a 32-bit system;
72 just fall through to the regular ptrace call in that case. */
73 {
74 char buf[8];
75
76 errno = 0;
77 ptrace (PPC_PTRACE_PEEKUSR_3264, tid,
78 (PTRACE_TYPE_ARG3) (regno * 8), buf);
79 if (errno == 0)
80 ptrace (PPC_PTRACE_PEEKUSR_3264, tid,
81 (PTRACE_TYPE_ARG3) (regno * 8 + 4), buf + 4);
82 if (errno == 0)
83 return (CORE_ADDR) *(unsigned long long *)buf;
84 }
85 #endif
86
87 errno = 0;
88 res = ptrace (PT_READ_U, tid,
89 (PTRACE_TYPE_ARG3) (regno * sizeof (PTRACE_TYPE_RET)), 0);
90 if (errno != 0)
91 {
92 char mess[128];
93 sprintf (mess, "reading PPC register #%d", regno);
94 perror_with_name (mess);
95 }
96
97 return (CORE_ADDR) (unsigned long) res;
98 }
99
100 /* Fetch WORD from PPU memory at (aligned) MEMADDR in thread TID. */
101 static int
102 fetch_ppc_memory_1 (int tid, CORE_ADDR memaddr, PTRACE_TYPE_RET *word)
103 {
104 errno = 0;
105
106 #ifndef __powerpc64__
107 if (memaddr >> 32)
108 {
109 unsigned long long addr_8 = (unsigned long long) memaddr;
110 ptrace (PPC_PTRACE_PEEKTEXT_3264, tid, (PTRACE_TYPE_ARG3) &addr_8, word);
111 }
112 else
113 #endif
114 *word = ptrace (PT_READ_I, tid, (PTRACE_TYPE_ARG3) (size_t) memaddr, 0);
115
116 return errno;
117 }
118
119 /* Store WORD into PPU memory at (aligned) MEMADDR in thread TID. */
120 static int
121 store_ppc_memory_1 (int tid, CORE_ADDR memaddr, PTRACE_TYPE_RET word)
122 {
123 errno = 0;
124
125 #ifndef __powerpc64__
126 if (memaddr >> 32)
127 {
128 unsigned long long addr_8 = (unsigned long long) memaddr;
129 ptrace (PPC_PTRACE_POKEDATA_3264, tid, (PTRACE_TYPE_ARG3) &addr_8, word);
130 }
131 else
132 #endif
133 ptrace (PT_WRITE_D, tid, (PTRACE_TYPE_ARG3) (size_t) memaddr, word);
134
135 return errno;
136 }
137
138 /* Fetch LEN bytes of PPU memory at MEMADDR to MYADDR. */
139 static int
140 fetch_ppc_memory (CORE_ADDR memaddr, char *myaddr, int len)
141 {
142 int i, ret;
143
144 CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_TYPE_RET);
145 int count = ((((memaddr + len) - addr) + sizeof (PTRACE_TYPE_RET) - 1)
146 / sizeof (PTRACE_TYPE_RET));
147 PTRACE_TYPE_RET *buffer;
148
149 int tid = ptid_get_lwp (current_ptid);
150
151 buffer = (PTRACE_TYPE_RET *) alloca (count * sizeof (PTRACE_TYPE_RET));
152 for (i = 0; i < count; i++, addr += sizeof (PTRACE_TYPE_RET))
153 if ((ret = fetch_ppc_memory_1 (tid, addr, &buffer[i])) != 0)
154 return ret;
155
156 memcpy (myaddr,
157 (char *) buffer + (memaddr & (sizeof (PTRACE_TYPE_RET) - 1)),
158 len);
159
160 return 0;
161 }
162
163 /* Store LEN bytes from MYADDR to PPU memory at MEMADDR. */
164 static int
165 store_ppc_memory (CORE_ADDR memaddr, char *myaddr, int len)
166 {
167 int i, ret;
168
169 CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_TYPE_RET);
170 int count = ((((memaddr + len) - addr) + sizeof (PTRACE_TYPE_RET) - 1)
171 / sizeof (PTRACE_TYPE_RET));
172 PTRACE_TYPE_RET *buffer;
173
174 int tid = ptid_get_lwp (current_ptid);
175
176 buffer = (PTRACE_TYPE_RET *) alloca (count * sizeof (PTRACE_TYPE_RET));
177
178 if (addr != memaddr || len < (int) sizeof (PTRACE_TYPE_RET))
179 if ((ret = fetch_ppc_memory_1 (tid, addr, &buffer[0])) != 0)
180 return ret;
181
182 if (count > 1)
183 if ((ret = fetch_ppc_memory_1 (tid, addr + (count - 1)
184 * sizeof (PTRACE_TYPE_RET),
185 &buffer[count - 1])) != 0)
186 return ret;
187
188 memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_TYPE_RET) - 1)),
189 myaddr, len);
190
191 for (i = 0; i < count; i++, addr += sizeof (PTRACE_TYPE_RET))
192 if ((ret = store_ppc_memory_1 (tid, addr, buffer[i])) != 0)
193 return ret;
194
195 return 0;
196 }
197
198
199 /* If the PPU thread is currently stopped on a spu_run system call,
200 return to FD and ADDR the file handle and NPC parameter address
201 used with the system call. Return non-zero if successful. */
202 static int
203 parse_spufs_run (int *fd, CORE_ADDR *addr)
204 {
205 unsigned int insn;
206 CORE_ADDR pc = fetch_ppc_register (32); /* nip */
207
208 /* Fetch instruction preceding current NIP. */
209 if (fetch_ppc_memory (pc-4, (char *) &insn, 4) != 0)
210 return 0;
211 /* It should be a "sc" instruction. */
212 if (insn != INSTR_SC)
213 return 0;
214 /* System call number should be NR_spu_run. */
215 if (fetch_ppc_register (0) != NR_spu_run)
216 return 0;
217
218 /* Register 3 contains fd, register 4 the NPC param pointer. */
219 *fd = fetch_ppc_register (34); /* orig_gpr3 */
220 *addr = fetch_ppc_register (4);
221 return 1;
222 }
223
224
225 /* Copy LEN bytes at OFFSET in spufs file ANNEX into/from READBUF or WRITEBUF,
226 using the /proc file system. */
227 static int
228 spu_proc_xfer_spu (const char *annex, unsigned char *readbuf,
229 const unsigned char *writebuf,
230 CORE_ADDR offset, int len)
231 {
232 char buf[128];
233 int fd = 0;
234 int ret = -1;
235
236 if (!annex)
237 return 0;
238
239 sprintf (buf, "/proc/%ld/fd/%s", ptid_get_lwp (current_ptid), annex);
240 fd = open (buf, writebuf? O_WRONLY : O_RDONLY);
241 if (fd <= 0)
242 return -1;
243
244 if (offset != 0
245 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
246 {
247 close (fd);
248 return 0;
249 }
250
251 if (writebuf)
252 ret = write (fd, writebuf, (size_t) len);
253 else if (readbuf)
254 ret = read (fd, readbuf, (size_t) len);
255
256 close (fd);
257 return ret;
258 }
259
260
261 /* Start an inferior process and returns its pid.
262 ALLARGS is a vector of program-name and args. */
263 static int
264 spu_create_inferior (char *program, char **allargs)
265 {
266 int pid;
267 ptid_t ptid;
268 struct process_info *proc;
269
270 pid = fork ();
271 if (pid < 0)
272 perror_with_name ("fork");
273
274 if (pid == 0)
275 {
276 close_most_fds ();
277 ptrace (PTRACE_TRACEME, 0, 0, 0);
278
279 setpgid (0, 0);
280
281 execv (program, allargs);
282 if (errno == ENOENT)
283 execvp (program, allargs);
284
285 fprintf (stderr, "Cannot exec %s: %s.\n", program,
286 strerror (errno));
287 fflush (stderr);
288 _exit (0177);
289 }
290
291 proc = add_process (pid, 0);
292 proc->tdesc = tdesc_spu;
293
294 ptid = ptid_build (pid, pid, 0);
295 add_thread (ptid, NULL);
296 return pid;
297 }
298
299 /* Attach to an inferior process. */
300 int
301 spu_attach (unsigned long pid)
302 {
303 ptid_t ptid;
304 struct process_info *proc;
305
306 if (ptrace (PTRACE_ATTACH, pid, 0, 0) != 0)
307 {
308 fprintf (stderr, "Cannot attach to process %ld: %s (%d)\n", pid,
309 strerror (errno), errno);
310 fflush (stderr);
311 _exit (0177);
312 }
313
314 proc = add_process (pid, 1);
315 proc->tdesc = tdesc_spu;
316 ptid = ptid_build (pid, pid, 0);
317 add_thread (ptid, NULL);
318 return 0;
319 }
320
321 /* Kill the inferior process. */
322 static int
323 spu_kill (int pid)
324 {
325 int status, ret;
326 struct process_info *process = find_process_pid (pid);
327 if (process == NULL)
328 return -1;
329
330 ptrace (PTRACE_KILL, pid, 0, 0);
331
332 do {
333 ret = waitpid (pid, &status, 0);
334 if (WIFEXITED (status) || WIFSIGNALED (status))
335 break;
336 } while (ret != -1 || errno != ECHILD);
337
338 clear_inferiors ();
339 remove_process (process);
340 return 0;
341 }
342
343 /* Detach from inferior process. */
344 static int
345 spu_detach (int pid)
346 {
347 struct process_info *process = find_process_pid (pid);
348 if (process == NULL)
349 return -1;
350
351 ptrace (PTRACE_DETACH, pid, 0, 0);
352
353 clear_inferiors ();
354 remove_process (process);
355 return 0;
356 }
357
358 static void
359 spu_mourn (struct process_info *process)
360 {
361 remove_process (process);
362 }
363
364 static void
365 spu_join (int pid)
366 {
367 int status, ret;
368
369 do {
370 ret = waitpid (pid, &status, 0);
371 if (WIFEXITED (status) || WIFSIGNALED (status))
372 break;
373 } while (ret != -1 || errno != ECHILD);
374 }
375
376 /* Return nonzero if the given thread is still alive. */
377 static int
378 spu_thread_alive (ptid_t ptid)
379 {
380 return ptid_equal (ptid, current_ptid);
381 }
382
383 /* Resume process. */
384 static void
385 spu_resume (struct thread_resume *resume_info, size_t n)
386 {
387 size_t i;
388
389 for (i = 0; i < n; i++)
390 if (ptid_equal (resume_info[i].thread, minus_one_ptid)
391 || ptid_equal (resume_info[i].thread, current_ptid))
392 break;
393
394 if (i == n)
395 return;
396
397 /* We don't support hardware single-stepping right now, assume
398 GDB knows to use software single-stepping. */
399 if (resume_info[i].kind == resume_step)
400 fprintf (stderr, "Hardware single-step not supported.\n");
401
402 regcache_invalidate ();
403
404 errno = 0;
405 ptrace (PTRACE_CONT, ptid_get_lwp (current_ptid), 0, resume_info[i].sig);
406 if (errno)
407 perror_with_name ("ptrace");
408 }
409
410 /* Wait for process, returns status. */
411 static ptid_t
412 spu_wait (ptid_t ptid, struct target_waitstatus *ourstatus, int options)
413 {
414 int pid = ptid_get_pid (ptid);
415 int w;
416 int ret;
417
418 while (1)
419 {
420 ret = waitpid (pid, &w, WNOHANG | __WALL | __WNOTHREAD);
421
422 if (ret == -1)
423 {
424 if (errno != ECHILD)
425 perror_with_name ("waitpid");
426 }
427 else if (ret > 0)
428 break;
429
430 usleep (1000);
431 }
432
433 /* On the first wait, continue running the inferior until we are
434 blocked inside an spu_run system call. */
435 if (!server_waiting)
436 {
437 int fd;
438 CORE_ADDR addr;
439
440 while (!parse_spufs_run (&fd, &addr))
441 {
442 ptrace (PT_SYSCALL, pid, (PTRACE_TYPE_ARG3) 0, 0);
443 waitpid (pid, NULL, __WALL | __WNOTHREAD);
444 }
445 }
446
447 if (WIFEXITED (w))
448 {
449 fprintf (stderr, "\nChild exited with retcode = %x \n", WEXITSTATUS (w));
450 ourstatus->kind = TARGET_WAITKIND_EXITED;
451 ourstatus->value.integer = WEXITSTATUS (w);
452 clear_inferiors ();
453 return pid_to_ptid (ret);
454 }
455 else if (!WIFSTOPPED (w))
456 {
457 fprintf (stderr, "\nChild terminated with signal = %x \n", WTERMSIG (w));
458 ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
459 ourstatus->value.sig = gdb_signal_from_host (WTERMSIG (w));
460 clear_inferiors ();
461 return pid_to_ptid (ret);
462 }
463
464 /* After attach, we may have received a SIGSTOP. Do not return this
465 as signal to GDB, or else it will try to continue with SIGSTOP ... */
466 if (!server_waiting)
467 {
468 ourstatus->kind = TARGET_WAITKIND_STOPPED;
469 ourstatus->value.sig = GDB_SIGNAL_0;
470 return ptid_build (ret, ret, 0);
471 }
472
473 ourstatus->kind = TARGET_WAITKIND_STOPPED;
474 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
475 return ptid_build (ret, ret, 0);
476 }
477
478 /* Fetch inferior registers. */
479 static void
480 spu_fetch_registers (struct regcache *regcache, int regno)
481 {
482 int fd;
483 CORE_ADDR addr;
484
485 /* We must be stopped on a spu_run system call. */
486 if (!parse_spufs_run (&fd, &addr))
487 return;
488
489 /* The ID register holds the spufs file handle. */
490 if (regno == -1 || regno == SPU_ID_REGNUM)
491 supply_register (regcache, SPU_ID_REGNUM, (char *)&fd);
492
493 /* The NPC register is found at ADDR. */
494 if (regno == -1 || regno == SPU_PC_REGNUM)
495 {
496 char buf[4];
497 if (fetch_ppc_memory (addr, buf, 4) == 0)
498 supply_register (regcache, SPU_PC_REGNUM, buf);
499 }
500
501 /* The GPRs are found in the "regs" spufs file. */
502 if (regno == -1 || (regno >= 0 && regno < SPU_NUM_CORE_REGS))
503 {
504 unsigned char buf[16*SPU_NUM_CORE_REGS];
505 char annex[32];
506 int i;
507
508 sprintf (annex, "%d/regs", fd);
509 if (spu_proc_xfer_spu (annex, buf, NULL, 0, sizeof buf) == sizeof buf)
510 for (i = 0; i < SPU_NUM_CORE_REGS; i++)
511 supply_register (regcache, i, buf + i*16);
512 }
513 }
514
515 /* Store inferior registers. */
516 static void
517 spu_store_registers (struct regcache *regcache, int regno)
518 {
519 int fd;
520 CORE_ADDR addr;
521
522 /* ??? Some callers use 0 to mean all registers. */
523 if (regno == 0)
524 regno = -1;
525
526 /* We must be stopped on a spu_run system call. */
527 if (!parse_spufs_run (&fd, &addr))
528 return;
529
530 /* The NPC register is found at ADDR. */
531 if (regno == -1 || regno == SPU_PC_REGNUM)
532 {
533 char buf[4];
534 collect_register (regcache, SPU_PC_REGNUM, buf);
535 store_ppc_memory (addr, buf, 4);
536 }
537
538 /* The GPRs are found in the "regs" spufs file. */
539 if (regno == -1 || (regno >= 0 && regno < SPU_NUM_CORE_REGS))
540 {
541 unsigned char buf[16*SPU_NUM_CORE_REGS];
542 char annex[32];
543 int i;
544
545 for (i = 0; i < SPU_NUM_CORE_REGS; i++)
546 collect_register (regcache, i, buf + i*16);
547
548 sprintf (annex, "%d/regs", fd);
549 spu_proc_xfer_spu (annex, NULL, buf, 0, sizeof buf);
550 }
551 }
552
553 /* Copy LEN bytes from inferior's memory starting at MEMADDR
554 to debugger memory starting at MYADDR. */
555 static int
556 spu_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
557 {
558 int fd, ret;
559 CORE_ADDR addr;
560 char annex[32], lslr_annex[32], buf[32];
561 CORE_ADDR lslr;
562
563 /* We must be stopped on a spu_run system call. */
564 if (!parse_spufs_run (&fd, &addr))
565 return 0;
566
567 /* Use the "mem" spufs file to access SPU local store. */
568 sprintf (annex, "%d/mem", fd);
569 ret = spu_proc_xfer_spu (annex, myaddr, NULL, memaddr, len);
570 if (ret > 0)
571 return ret == len ? 0 : EIO;
572
573 /* SPU local store access wraps the address around at the
574 local store limit. We emulate this here. To avoid needing
575 an extra access to retrieve the LSLR, we only do that after
576 trying the original address first, and getting end-of-file. */
577 sprintf (lslr_annex, "%d/lslr", fd);
578 memset (buf, 0, sizeof buf);
579 if (spu_proc_xfer_spu (lslr_annex, (unsigned char *)buf, NULL,
580 0, sizeof buf) <= 0)
581 return ret;
582
583 lslr = strtoul (buf, NULL, 16);
584 ret = spu_proc_xfer_spu (annex, myaddr, NULL, memaddr & lslr, len);
585
586 return ret == len ? 0 : EIO;
587 }
588
589 /* Copy LEN bytes of data from debugger memory at MYADDR
590 to inferior's memory at MEMADDR.
591 On failure (cannot write the inferior)
592 returns the value of errno. */
593 static int
594 spu_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len)
595 {
596 int fd, ret;
597 CORE_ADDR addr;
598 char annex[32], lslr_annex[32], buf[32];
599 CORE_ADDR lslr;
600
601 /* We must be stopped on a spu_run system call. */
602 if (!parse_spufs_run (&fd, &addr))
603 return 0;
604
605 /* Use the "mem" spufs file to access SPU local store. */
606 sprintf (annex, "%d/mem", fd);
607 ret = spu_proc_xfer_spu (annex, NULL, myaddr, memaddr, len);
608 if (ret > 0)
609 return ret == len ? 0 : EIO;
610
611 /* SPU local store access wraps the address around at the
612 local store limit. We emulate this here. To avoid needing
613 an extra access to retrieve the LSLR, we only do that after
614 trying the original address first, and getting end-of-file. */
615 sprintf (lslr_annex, "%d/lslr", fd);
616 memset (buf, 0, sizeof buf);
617 if (spu_proc_xfer_spu (lslr_annex, (unsigned char *)buf, NULL,
618 0, sizeof buf) <= 0)
619 return ret;
620
621 lslr = strtoul (buf, NULL, 16);
622 ret = spu_proc_xfer_spu (annex, NULL, myaddr, memaddr & lslr, len);
623
624 return ret == len ? 0 : EIO;
625 }
626
627 /* Look up special symbols -- unneded here. */
628 static void
629 spu_look_up_symbols (void)
630 {
631 }
632
633 /* Send signal to inferior. */
634 static void
635 spu_request_interrupt (void)
636 {
637 syscall (SYS_tkill, ptid_get_lwp (current_ptid), SIGINT);
638 }
639
640 static struct target_ops spu_target_ops = {
641 spu_create_inferior,
642 spu_attach,
643 spu_kill,
644 spu_detach,
645 spu_mourn,
646 spu_join,
647 spu_thread_alive,
648 spu_resume,
649 spu_wait,
650 spu_fetch_registers,
651 spu_store_registers,
652 NULL, /* prepare_to_access_memory */
653 NULL, /* done_accessing_memory */
654 spu_read_memory,
655 spu_write_memory,
656 spu_look_up_symbols,
657 spu_request_interrupt,
658 NULL,
659 NULL, /* supports_z_point_type */
660 NULL,
661 NULL,
662 NULL,
663 NULL,
664 NULL,
665 NULL,
666 spu_proc_xfer_spu,
667 hostio_last_error_from_errno,
668 };
669
670 void
671 initialize_low (void)
672 {
673 static const unsigned char breakpoint[] = { 0x00, 0x00, 0x3f, 0xff };
674
675 set_target_ops (&spu_target_ops);
676 set_breakpoint_data (breakpoint, sizeof breakpoint);
677 init_registers_spu ();
678 }
This page took 0.058973 seconds and 4 git commands to generate.