db_interface.c revision 1.37 1 /* $NetBSD: db_interface.c,v 1.37 2005/06/02 19:33:04 uwe Exp $ */
2
3 /*
4 * Copyright (c) 1996 Scott K. Stevens
5 *
6 * Mach Operating System
7 * Copyright (c) 1991,1990 Carnegie Mellon University
8 * All Rights Reserved.
9 *
10 * Permission to use, copy, modify and distribute this software and its
11 * documentation is hereby granted, provided that both the copyright
12 * notice and this permission notice appear in all copies of the
13 * software, derivative works or modified versions, and any portions
14 * thereof, and that both notices appear in supporting documentation.
15 *
16 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
17 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
18 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
19 *
20 * Carnegie Mellon requests users of this software to return to
21 *
22 * Software Distribution Coordinator or Software.Distribution (at) CS.CMU.EDU
23 * School of Computer Science
24 * Carnegie Mellon University
25 * Pittsburgh PA 15213-3890
26 *
27 * any improvements or extensions that they make and grant Carnegie the
28 * rights to redistribute these changes.
29 *
30 * From: db_interface.c,v 2.4 1991/02/05 17:11:13 mrt (CMU)
31 */
32
33 /*
34 * Interface to new debugger.
35 */
36
37 #include <sys/cdefs.h>
38 __KERNEL_RCSID(0, "$NetBSD: db_interface.c,v 1.37 2005/06/02 19:33:04 uwe Exp $");
39
40 #include "opt_ddb.h"
41 #include "opt_kgdb.h"
42
43 #include <sys/param.h>
44 #include <sys/proc.h>
45 #include <sys/reboot.h>
46 #include <sys/systm.h> /* just for boothowto */
47 #include <sys/exec.h>
48
49 #include <uvm/uvm_extern.h>
50
51 #include <arm/arm32/db_machdep.h>
52 #include <arm/arm32/katelib.h>
53 #include <arm/undefined.h>
54 #include <ddb/db_access.h>
55 #include <ddb/db_command.h>
56 #include <ddb/db_output.h>
57 #include <ddb/db_variables.h>
58 #include <ddb/db_sym.h>
59 #include <ddb/db_extern.h>
60 #include <ddb/db_interface.h>
61 #include <dev/cons.h>
62
63 #if defined(KGDB) || !defined(DDB)
64 #define db_printf printf
65 #endif
66
67 static long nil;
68
69 int db_access_und_sp __P((const struct db_variable *, db_expr_t *, int));
70 int db_access_abt_sp __P((const struct db_variable *, db_expr_t *, int));
71 int db_access_irq_sp __P((const struct db_variable *, db_expr_t *, int));
72 u_int db_fetch_reg __P((int, db_regs_t *));
73
74 int db_trapper __P((u_int, u_int, trapframe_t *, int));
75
76 const struct db_variable db_regs[] = {
77 { "spsr", (long *)&DDB_REGS->tf_spsr, FCN_NULL, },
78 { "r0", (long *)&DDB_REGS->tf_r0, FCN_NULL, },
79 { "r1", (long *)&DDB_REGS->tf_r1, FCN_NULL, },
80 { "r2", (long *)&DDB_REGS->tf_r2, FCN_NULL, },
81 { "r3", (long *)&DDB_REGS->tf_r3, FCN_NULL, },
82 { "r4", (long *)&DDB_REGS->tf_r4, FCN_NULL, },
83 { "r5", (long *)&DDB_REGS->tf_r5, FCN_NULL, },
84 { "r6", (long *)&DDB_REGS->tf_r6, FCN_NULL, },
85 { "r7", (long *)&DDB_REGS->tf_r7, FCN_NULL, },
86 { "r8", (long *)&DDB_REGS->tf_r8, FCN_NULL, },
87 { "r9", (long *)&DDB_REGS->tf_r9, FCN_NULL, },
88 { "r10", (long *)&DDB_REGS->tf_r10, FCN_NULL, },
89 { "r11", (long *)&DDB_REGS->tf_r11, FCN_NULL, },
90 { "r12", (long *)&DDB_REGS->tf_r12, FCN_NULL, },
91 { "usr_sp", (long *)&DDB_REGS->tf_usr_sp, FCN_NULL, },
92 { "usr_lr", (long *)&DDB_REGS->tf_usr_lr, FCN_NULL, },
93 { "svc_sp", (long *)&DDB_REGS->tf_svc_sp, FCN_NULL, },
94 { "svc_lr", (long *)&DDB_REGS->tf_svc_lr, FCN_NULL, },
95 { "pc", (long *)&DDB_REGS->tf_pc, FCN_NULL, },
96 { "und_sp", &nil, db_access_und_sp, },
97 { "abt_sp", &nil, db_access_abt_sp, },
98 { "irq_sp", &nil, db_access_irq_sp, },
99 };
100
101 const struct db_variable * const db_eregs = db_regs + sizeof(db_regs)/sizeof(db_regs[0]);
102
103 int db_active = 0;
104
105 int
106 db_access_und_sp(const struct db_variable *vp, db_expr_t *valp, int rw)
107 {
108
109 if (rw == DB_VAR_GET)
110 *valp = get_stackptr(PSR_UND32_MODE);
111 return(0);
112 }
113
114 int
115 db_access_abt_sp(const struct db_variable *vp, db_expr_t *valp, int rw)
116 {
117
118 if (rw == DB_VAR_GET)
119 *valp = get_stackptr(PSR_ABT32_MODE);
120 return(0);
121 }
122
123 int
124 db_access_irq_sp(const struct db_variable *vp, db_expr_t *valp, int rw)
125 {
126
127 if (rw == DB_VAR_GET)
128 *valp = get_stackptr(PSR_IRQ32_MODE);
129 return(0);
130 }
131
132 #ifdef DDB
133 /*
134 * kdb_trap - field a TRACE or BPT trap
135 */
136 int
137 kdb_trap(int type, db_regs_t *regs)
138 {
139 int s;
140
141 switch (type) {
142 case T_BREAKPOINT: /* breakpoint */
143 case -1: /* keyboard interrupt */
144 break;
145 default:
146 if (db_recover != 0) {
147 /* This will longjmp back into db_command_loop() */
148 db_error("Faulted in DDB; continuing...\n");
149 /*NOTREACHED*/
150 }
151 }
152
153 /* Should switch to kdb`s own stack here. */
154
155 ddb_regs = *regs;
156
157 s = splhigh();
158 db_active++;
159 cnpollc(TRUE);
160 db_trap(type, 0/*code*/);
161 cnpollc(FALSE);
162 db_active--;
163 splx(s);
164
165 *regs = ddb_regs;
166
167 return (1);
168 }
169 #endif
170
171 int
172 db_validate_address(vaddr_t addr)
173 {
174 struct proc *p = curproc;
175 struct pmap *pmap;
176
177 if (!p || !p->p_vmspace || !p->p_vmspace->vm_map.pmap ||
178 #ifndef ARM32_NEW_VM_LAYOUT
179 addr >= VM_MAXUSER_ADDRESS
180 #else
181 addr >= VM_MIN_KERNEL_ADDRESS
182 #endif
183 )
184 pmap = pmap_kernel();
185 else
186 pmap = p->p_vmspace->vm_map.pmap;
187
188 return (pmap_extract(pmap, addr, NULL) == FALSE);
189 }
190
191 /*
192 * Read bytes from kernel address space for debugger.
193 */
194 void
195 db_read_bytes(addr, size, data)
196 vaddr_t addr;
197 size_t size;
198 char *data;
199 {
200 char *src = (char *)addr;
201
202 if (db_validate_address((u_int)src)) {
203 db_printf("address %p is invalid\n", src);
204 return;
205 }
206
207 if (size == 4 && (addr & 3) == 0 && ((uintptr_t)data & 3) == 0) {
208 *((int*)data) = *((int*)src);
209 return;
210 }
211
212 if (size == 2 && (addr & 1) == 0 && ((uintptr_t)data & 1) == 0) {
213 *((short*)data) = *((short*)src);
214 return;
215 }
216
217 while (size-- > 0) {
218 if (db_validate_address((u_int)src)) {
219 db_printf("address %p is invalid\n", src);
220 return;
221 }
222 *data++ = *src++;
223 }
224 }
225
226 static void
227 db_write_text(vaddr_t addr, size_t size, const char *data)
228 {
229 struct pmap *pmap = pmap_kernel();
230 pd_entry_t *pde, oldpde, tmppde;
231 pt_entry_t *pte, oldpte, tmppte;
232 vaddr_t pgva;
233 size_t limit, savesize;
234 char *dst;
235
236 /* XXX: gcc */
237 oldpte = 0;
238
239 if ((savesize = size) == 0)
240 return;
241
242 dst = (char *) addr;
243
244 do {
245 /* Get the PDE of the current VA. */
246 if (pmap_get_pde_pte(pmap, (vaddr_t) dst, &pde, &pte) == FALSE)
247 goto no_mapping;
248 switch ((oldpde = *pde) & L1_TYPE_MASK) {
249 case L1_TYPE_S:
250 pgva = (vaddr_t)dst & L1_S_FRAME;
251 limit = L1_S_SIZE - ((vaddr_t)dst & L1_S_OFFSET);
252
253 tmppde = oldpde | L1_S_PROT_W;
254 *pde = tmppde;
255 PTE_SYNC(pde);
256 break;
257
258 case L1_TYPE_C:
259 pgva = (vaddr_t)dst & L2_S_FRAME;
260 limit = L2_S_SIZE - ((vaddr_t)dst & L2_S_OFFSET);
261
262 if (pte == NULL)
263 goto no_mapping;
264 oldpte = *pte;
265 tmppte = oldpte | L2_S_PROT_W;
266 *pte = tmppte;
267 PTE_SYNC(pte);
268 break;
269
270 default:
271 no_mapping:
272 printf(" address 0x%08lx not a valid page\n",
273 (vaddr_t) dst);
274 return;
275 }
276 cpu_tlb_flushD_SE(pgva);
277 cpu_cpwait();
278
279 if (limit > size)
280 limit = size;
281 size -= limit;
282
283 /*
284 * Page is now writable. Do as much access as we
285 * can in this page.
286 */
287 for (; limit > 0; limit--)
288 *dst++ = *data++;
289
290 /*
291 * Restore old mapping permissions.
292 */
293 switch (oldpde & L1_TYPE_MASK) {
294 case L1_TYPE_S:
295 *pde = oldpde;
296 PTE_SYNC(pde);
297 break;
298
299 case L1_TYPE_C:
300 *pte = oldpte;
301 PTE_SYNC(pte);
302 break;
303 }
304 cpu_tlb_flushD_SE(pgva);
305 cpu_cpwait();
306 } while (size != 0);
307
308 /* Sync the I-cache. */
309 cpu_icache_sync_range(addr, savesize);
310 }
311
312 /*
313 * Write bytes to kernel address space for debugger.
314 */
315 void
316 db_write_bytes(vaddr_t addr, size_t size, const char *data)
317 {
318 extern char kernel_text[];
319 extern char etext[];
320 char *dst;
321 size_t loop;
322
323 /* If any part is in kernel text, use db_write_text() */
324 if (addr >= (vaddr_t) kernel_text && addr < (vaddr_t) etext) {
325 db_write_text(addr, size, data);
326 return;
327 }
328
329 dst = (char *)addr;
330 if (db_validate_address((u_int)dst)) {
331 db_printf("address %p is invalid\n", dst);
332 return;
333 }
334
335 if (size == 4 && (addr & 3) == 0 && ((uintptr_t)data & 3) == 0)
336 *((int*)dst) = *((const int *)data);
337 else
338 if (size == 2 && (addr & 1) == 0 && ((uintptr_t)data & 1) == 0)
339 *((short*)dst) = *((const short *)data);
340 else {
341 loop = size;
342 while (loop-- > 0) {
343 if (db_validate_address((u_int)dst)) {
344 db_printf("address %p is invalid\n", dst);
345 return;
346 }
347 *dst++ = *data++;
348 }
349 }
350
351 /* make sure the caches and memory are in sync */
352 cpu_icache_sync_range(addr, size);
353
354 /* In case the current page tables have been modified ... */
355 cpu_tlb_flushID();
356 cpu_cpwait();
357 }
358
359 #ifdef DDB
360 void
361 cpu_Debugger(void)
362 {
363 asm(".word 0xe7ffffff");
364 }
365
366 const struct db_command db_machine_command_table[] = {
367 { "frame", db_show_frame_cmd, 0, NULL },
368 { "panic", db_show_panic_cmd, 0, NULL },
369 #ifdef ARM32_DB_COMMANDS
370 ARM32_DB_COMMANDS,
371 #endif
372 { NULL, NULL, 0, NULL }
373 };
374
375 int
376 db_trapper(u_int addr, u_int inst, trapframe_t *frame, int fault_code)
377 {
378
379 if (fault_code == 0) {
380 if ((inst & ~INSN_COND_MASK) == (BKPT_INST & ~INSN_COND_MASK))
381 kdb_trap(T_BREAKPOINT, frame);
382 else
383 kdb_trap(-1, frame);
384 } else
385 return (1);
386 return (0);
387 }
388
389 extern u_int esym;
390 extern u_int end;
391
392 static struct undefined_handler db_uh;
393
394 void
395 db_machine_init(void)
396 {
397
398 /*
399 * We get called before malloc() is available, so supply a static
400 * struct undefined_handler.
401 */
402 db_uh.uh_handler = db_trapper;
403 install_coproc_handler_static(CORE_UNKNOWN_HANDLER, &db_uh);
404 }
405 #endif
406
407 u_int
408 db_fetch_reg(int reg, db_regs_t *regs)
409 {
410
411 switch (reg) {
412 case 0:
413 return (regs->tf_r0);
414 case 1:
415 return (regs->tf_r1);
416 case 2:
417 return (regs->tf_r2);
418 case 3:
419 return (regs->tf_r3);
420 case 4:
421 return (regs->tf_r4);
422 case 5:
423 return (regs->tf_r5);
424 case 6:
425 return (regs->tf_r6);
426 case 7:
427 return (regs->tf_r7);
428 case 8:
429 return (regs->tf_r8);
430 case 9:
431 return (regs->tf_r9);
432 case 10:
433 return (regs->tf_r10);
434 case 11:
435 return (regs->tf_r11);
436 case 12:
437 return (regs->tf_r12);
438 case 13:
439 return (regs->tf_svc_sp);
440 case 14:
441 return (regs->tf_svc_lr);
442 case 15:
443 return (regs->tf_pc);
444 default:
445 panic("db_fetch_reg: botch");
446 }
447 }
448
449 u_int
450 branch_taken(u_int insn, u_int pc, db_regs_t *regs)
451 {
452 u_int addr, nregs;
453
454 switch ((insn >> 24) & 0xf) {
455 case 0xa: /* b ... */
456 case 0xb: /* bl ... */
457 addr = ((insn << 2) & 0x03ffffff);
458 if (addr & 0x02000000)
459 addr |= 0xfc000000;
460 return (pc + 8 + addr);
461 case 0x7: /* ldr pc, [pc, reg, lsl #2] */
462 addr = db_fetch_reg(insn & 0xf, regs);
463 addr = pc + 8 + (addr << 2);
464 db_read_bytes(addr, 4, (char *)&addr);
465 return (addr);
466 case 0x1: /* mov pc, reg */
467 addr = db_fetch_reg(insn & 0xf, regs);
468 return (addr);
469 case 0x8: /* ldmxx reg, {..., pc} */
470 case 0x9:
471 addr = db_fetch_reg((insn >> 16) & 0xf, regs);
472 nregs = (insn & 0x5555) + ((insn >> 1) & 0x5555);
473 nregs = (nregs & 0x3333) + ((nregs >> 2) & 0x3333);
474 nregs = (nregs + (nregs >> 4)) & 0x0f0f;
475 nregs = (nregs + (nregs >> 8)) & 0x001f;
476 switch ((insn >> 23) & 0x3) {
477 case 0x0: /* ldmda */
478 addr = addr - 0;
479 break;
480 case 0x1: /* ldmia */
481 addr = addr + 0 + ((nregs - 1) << 2);
482 break;
483 case 0x2: /* ldmdb */
484 addr = addr - 4;
485 break;
486 case 0x3: /* ldmib */
487 addr = addr + 4 + ((nregs - 1) << 2);
488 break;
489 }
490 db_read_bytes(addr, 4, (char *)&addr);
491 return (addr);
492 default:
493 panic("branch_taken: botch");
494 }
495 }
496