db_interface.c revision 1.33 1 /* $NetBSD: db_interface.c,v 1.33 2003/08/25 04:51:10 mrg 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 1.33 2003/08/25 04:51:10 mrg 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, 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 if ((savesize = size) == 0)
237 return;
238
239 dst = (char *) addr;
240
241 do {
242 /* Get the PDE of the current VA. */
243 if (pmap_get_pde_pte(pmap, (vaddr_t) dst, &pde, &pte) == FALSE)
244 goto no_mapping;
245 switch ((oldpde = *pde) & L1_TYPE_MASK) {
246 case L1_TYPE_S:
247 pgva = (vaddr_t)dst & L1_S_FRAME;
248 limit = L1_S_SIZE - ((vaddr_t)dst & L1_S_OFFSET);
249
250 tmppde = oldpde | L1_S_PROT_W;
251 *pde = tmppde;
252 PTE_SYNC(pde);
253 break;
254
255 case L1_TYPE_C:
256 pgva = (vaddr_t)dst & L2_S_FRAME;
257 limit = L2_S_SIZE - ((vaddr_t)dst & L2_S_OFFSET);
258
259 if (pte == NULL)
260 goto no_mapping;
261 oldpte = *pte;
262 tmppte = oldpte | L2_S_PROT_W;
263 *pte = tmppte;
264 PTE_SYNC(pte);
265 break;
266
267 default:
268 no_mapping:
269 printf(" address 0x%08lx not a valid page\n",
270 (vaddr_t) dst);
271 return;
272 }
273 cpu_tlb_flushD_SE(pgva);
274 cpu_cpwait();
275
276 if (limit > size)
277 limit = size;
278 size -= limit;
279
280 /*
281 * Page is now writable. Do as much access as we
282 * can in this page.
283 */
284 for (; limit > 0; limit--)
285 *dst++ = *data++;
286
287 /*
288 * Restore old mapping permissions.
289 */
290 switch (oldpde & L1_TYPE_MASK) {
291 case L1_TYPE_S:
292 *pde = oldpde;
293 PTE_SYNC(pde);
294 break;
295
296 case L1_TYPE_C:
297 *pte = oldpte;
298 PTE_SYNC(pte);
299 break;
300 }
301 cpu_tlb_flushD_SE(pgva);
302 cpu_cpwait();
303 } while (size != 0);
304
305 /* Sync the I-cache. */
306 cpu_icache_sync_range(addr, savesize);
307 }
308
309 /*
310 * Write bytes to kernel address space for debugger.
311 */
312 void
313 db_write_bytes(vaddr_t addr, size_t size, char *data)
314 {
315 extern char kernel_text[];
316 extern char etext[];
317 char *dst;
318 size_t loop;
319
320 /* If any part is in kernel text, use db_write_text() */
321 if (addr >= (vaddr_t) kernel_text && addr < (vaddr_t) etext) {
322 db_write_text(addr, size, data);
323 return;
324 }
325
326 dst = (char *)addr;
327 if (db_validate_address((u_int)dst)) {
328 db_printf("address %p is invalid\n", dst);
329 return;
330 }
331
332 if (size == 4 && (addr & 3) == 0 && ((uintptr_t)data & 3) == 0)
333 *((int*)dst) = *((int*)data);
334 else
335 if (size == 2 && (addr & 1) == 0 && ((uintptr_t)data & 1) == 0)
336 *((short*)dst) = *((short*)data);
337 else {
338 loop = size;
339 while (loop-- > 0) {
340 if (db_validate_address((u_int)dst)) {
341 db_printf("address %p is invalid\n", dst);
342 return;
343 }
344 *dst++ = *data++;
345 }
346 }
347
348 /* make sure the caches and memory are in sync */
349 cpu_icache_sync_range(addr, size);
350
351 /* In case the current page tables have been modified ... */
352 cpu_tlb_flushID();
353 cpu_cpwait();
354 }
355
356 #ifdef DDB
357 void
358 cpu_Debugger(void)
359 {
360 asm(".word 0xe7ffffff");
361 }
362
363 const struct db_command db_machine_command_table[] = {
364 { "frame", db_show_frame_cmd, 0, NULL },
365 { "panic", db_show_panic_cmd, 0, NULL },
366 #ifdef ARM32_DB_COMMANDS
367 ARM32_DB_COMMANDS,
368 #endif
369 { NULL, NULL, 0, NULL }
370 };
371
372 int
373 db_trapper(u_int addr, u_int inst, trapframe_t *frame, int fault_code)
374 {
375
376 if (fault_code == 0) {
377 if ((inst & ~INSN_COND_MASK) == (BKPT_INST & ~INSN_COND_MASK))
378 kdb_trap(T_BREAKPOINT, frame);
379 else
380 kdb_trap(-1, frame);
381 } else
382 return (1);
383 return (0);
384 }
385
386 extern u_int esym;
387 extern u_int end;
388
389 static struct undefined_handler db_uh;
390
391 void
392 db_machine_init(void)
393 {
394
395 /*
396 * We get called before malloc() is available, so supply a static
397 * struct undefined_handler.
398 */
399 db_uh.uh_handler = db_trapper;
400 install_coproc_handler_static(0, &db_uh);
401 }
402 #endif
403
404 u_int
405 db_fetch_reg(int reg, db_regs_t *db_regs)
406 {
407
408 switch (reg) {
409 case 0:
410 return (db_regs->tf_r0);
411 case 1:
412 return (db_regs->tf_r1);
413 case 2:
414 return (db_regs->tf_r2);
415 case 3:
416 return (db_regs->tf_r3);
417 case 4:
418 return (db_regs->tf_r4);
419 case 5:
420 return (db_regs->tf_r5);
421 case 6:
422 return (db_regs->tf_r6);
423 case 7:
424 return (db_regs->tf_r7);
425 case 8:
426 return (db_regs->tf_r8);
427 case 9:
428 return (db_regs->tf_r9);
429 case 10:
430 return (db_regs->tf_r10);
431 case 11:
432 return (db_regs->tf_r11);
433 case 12:
434 return (db_regs->tf_r12);
435 case 13:
436 return (db_regs->tf_svc_sp);
437 case 14:
438 return (db_regs->tf_svc_lr);
439 case 15:
440 return (db_regs->tf_pc);
441 default:
442 panic("db_fetch_reg: botch");
443 }
444 }
445
446 u_int
447 branch_taken(u_int insn, u_int pc, db_regs_t *db_regs)
448 {
449 u_int addr, nregs;
450
451 switch ((insn >> 24) & 0xf) {
452 case 0xa: /* b ... */
453 case 0xb: /* bl ... */
454 addr = ((insn << 2) & 0x03ffffff);
455 if (addr & 0x02000000)
456 addr |= 0xfc000000;
457 return (pc + 8 + addr);
458 case 0x7: /* ldr pc, [pc, reg, lsl #2] */
459 addr = db_fetch_reg(insn & 0xf, db_regs);
460 addr = pc + 8 + (addr << 2);
461 db_read_bytes(addr, 4, (char *)&addr);
462 return (addr);
463 case 0x1: /* mov pc, reg */
464 addr = db_fetch_reg(insn & 0xf, db_regs);
465 return (addr);
466 case 0x8: /* ldmxx reg, {..., pc} */
467 case 0x9:
468 addr = db_fetch_reg((insn >> 16) & 0xf, db_regs);
469 nregs = (insn & 0x5555) + ((insn >> 1) & 0x5555);
470 nregs = (nregs & 0x3333) + ((nregs >> 2) & 0x3333);
471 nregs = (nregs + (nregs >> 4)) & 0x0f0f;
472 nregs = (nregs + (nregs >> 8)) & 0x001f;
473 switch ((insn >> 23) & 0x3) {
474 case 0x0: /* ldmda */
475 addr = addr - 0;
476 break;
477 case 0x1: /* ldmia */
478 addr = addr + 0 + ((nregs - 1) << 2);
479 break;
480 case 0x2: /* ldmdb */
481 addr = addr - 4;
482 break;
483 case 0x3: /* ldmib */
484 addr = addr + 4 + ((nregs - 1) << 2);
485 break;
486 }
487 db_read_bytes(addr, 4, (char *)&addr);
488 return (addr);
489 default:
490 panic("branch_taken: botch");
491 }
492 }
493