db_interface.c revision 1.30 1 /* $NetBSD: db_interface.c,v 1.30 2003/06/06 10:07:07 scw 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 #include "opt_ddb.h"
37 #include "opt_kgdb.h"
38
39 #include <sys/param.h>
40 #include <sys/proc.h>
41 #include <sys/reboot.h>
42 #include <sys/systm.h> /* just for boothowto */
43 #include <sys/exec.h>
44
45 #include <uvm/uvm_extern.h>
46
47 #include <arm/arm32/db_machdep.h>
48 #include <arm/arm32/katelib.h>
49 #include <arm/undefined.h>
50 #include <ddb/db_access.h>
51 #include <ddb/db_command.h>
52 #include <ddb/db_output.h>
53 #include <ddb/db_variables.h>
54 #include <ddb/db_sym.h>
55 #include <ddb/db_extern.h>
56 #include <ddb/db_interface.h>
57 #include <dev/cons.h>
58
59 #if defined(KGDB) || !defined(DDB)
60 #define db_printf printf
61 #endif
62
63 static int nil;
64
65 int db_access_und_sp __P((const struct db_variable *, db_expr_t *, int));
66 int db_access_abt_sp __P((const struct db_variable *, db_expr_t *, int));
67 int db_access_irq_sp __P((const struct db_variable *, db_expr_t *, int));
68 u_int db_fetch_reg __P((int, db_regs_t *));
69
70 int db_trapper __P((u_int, u_int, trapframe_t *, int));
71
72 const struct db_variable db_regs[] = {
73 { "spsr", (long *)&DDB_REGS->tf_spsr, FCN_NULL, },
74 { "r0", (long *)&DDB_REGS->tf_r0, FCN_NULL, },
75 { "r1", (long *)&DDB_REGS->tf_r1, FCN_NULL, },
76 { "r2", (long *)&DDB_REGS->tf_r2, FCN_NULL, },
77 { "r3", (long *)&DDB_REGS->tf_r3, FCN_NULL, },
78 { "r4", (long *)&DDB_REGS->tf_r4, FCN_NULL, },
79 { "r5", (long *)&DDB_REGS->tf_r5, FCN_NULL, },
80 { "r6", (long *)&DDB_REGS->tf_r6, FCN_NULL, },
81 { "r7", (long *)&DDB_REGS->tf_r7, FCN_NULL, },
82 { "r8", (long *)&DDB_REGS->tf_r8, FCN_NULL, },
83 { "r9", (long *)&DDB_REGS->tf_r9, FCN_NULL, },
84 { "r10", (long *)&DDB_REGS->tf_r10, FCN_NULL, },
85 { "r11", (long *)&DDB_REGS->tf_r11, FCN_NULL, },
86 { "r12", (long *)&DDB_REGS->tf_r12, FCN_NULL, },
87 { "usr_sp", (long *)&DDB_REGS->tf_usr_sp, FCN_NULL, },
88 { "usr_lr", (long *)&DDB_REGS->tf_usr_lr, FCN_NULL, },
89 { "svc_sp", (long *)&DDB_REGS->tf_svc_sp, FCN_NULL, },
90 { "svc_lr", (long *)&DDB_REGS->tf_svc_lr, FCN_NULL, },
91 { "pc", (long *)&DDB_REGS->tf_pc, FCN_NULL, },
92 { "und_sp", (long *)&nil, db_access_und_sp, },
93 { "abt_sp", (long *)&nil, db_access_abt_sp, },
94 { "irq_sp", (long *)&nil, db_access_irq_sp, },
95 };
96
97 const struct db_variable * const db_eregs = db_regs + sizeof(db_regs)/sizeof(db_regs[0]);
98
99 int db_active = 0;
100
101 int
102 db_access_und_sp(const struct db_variable *vp, db_expr_t *valp, int rw)
103 {
104
105 if (rw == DB_VAR_GET)
106 *valp = get_stackptr(PSR_UND32_MODE);
107 return(0);
108 }
109
110 int
111 db_access_abt_sp(const struct db_variable *vp, db_expr_t *valp, int rw)
112 {
113
114 if (rw == DB_VAR_GET)
115 *valp = get_stackptr(PSR_ABT32_MODE);
116 return(0);
117 }
118
119 int
120 db_access_irq_sp(const struct db_variable *vp, db_expr_t *valp, int rw)
121 {
122
123 if (rw == DB_VAR_GET)
124 *valp = get_stackptr(PSR_IRQ32_MODE);
125 return(0);
126 }
127
128 #ifdef DDB
129 /*
130 * kdb_trap - field a TRACE or BPT trap
131 */
132 int
133 kdb_trap(int type, db_regs_t *regs)
134 {
135 int s;
136
137 switch (type) {
138 case T_BREAKPOINT: /* breakpoint */
139 case -1: /* keyboard interrupt */
140 break;
141 default:
142 db_printf("kernel: trap");
143 if (db_recover != 0) {
144 db_error("Faulted in DDB; continuing...\n");
145 /*NOTREACHED*/
146 }
147 }
148
149 /* Should switch to kdb`s own stack here. */
150
151 ddb_regs = *regs;
152
153 s = splhigh();
154 db_active++;
155 cnpollc(TRUE);
156 db_trap(type, 0/*code*/);
157 cnpollc(FALSE);
158 db_active--;
159 splx(s);
160
161 *regs = ddb_regs;
162
163 return (1);
164 }
165 #endif
166
167 int
168 db_validate_address(vaddr_t addr)
169 {
170 struct proc *p = curproc;
171 struct pmap *pmap;
172
173 if (!p || !p->p_vmspace || !p->p_vmspace->vm_map.pmap ||
174 #ifndef ARM32_NEW_VM_LAYOUT
175 addr >= VM_MAXUSER_ADDRESS
176 #else
177 addr >= VM_MIN_KERNEL_ADDRESS
178 #endif
179 )
180 pmap = pmap_kernel();
181 else
182 pmap = p->p_vmspace->vm_map.pmap;
183
184 return (pmap_extract(pmap, addr, NULL) == FALSE);
185 }
186
187 /*
188 * Read bytes from kernel address space for debugger.
189 */
190 void
191 db_read_bytes(addr, size, data)
192 vaddr_t addr;
193 size_t size;
194 char *data;
195 {
196 char *src = (char *)addr;
197
198 if (db_validate_address((u_int)src)) {
199 db_printf("address %p is invalid\n", src);
200 return;
201 }
202
203 if (size == 4 && (addr & 3) == 0 && ((uintptr_t)data & 3) == 0) {
204 *((int*)data) = *((int*)src);
205 return;
206 }
207
208 if (size == 2 && (addr & 1) == 0 && ((uintptr_t)data & 1) == 0) {
209 *((short*)data) = *((short*)src);
210 return;
211 }
212
213 while (size-- > 0) {
214 if (db_validate_address((u_int)src)) {
215 db_printf("address %p is invalid\n", src);
216 return;
217 }
218 *data++ = *src++;
219 }
220 }
221
222 static void
223 db_write_text(vaddr_t addr, size_t size, char *data)
224 {
225 struct pmap *pmap = pmap_kernel();
226 pd_entry_t *pde, oldpde, tmppde;
227 pt_entry_t *pte, oldpte, tmppte;
228 vaddr_t pgva;
229 size_t limit, savesize;
230 char *dst;
231
232 if ((savesize = size) == 0)
233 return;
234
235 dst = (char *) addr;
236
237 do {
238 /* Get the PDE of the current VA. */
239 if (pmap_get_pde_pte(pmap, (vaddr_t) dst, &pde, &pte) == FALSE)
240 goto no_mapping;
241 switch ((oldpde = *pde) & L1_TYPE_MASK) {
242 case L1_TYPE_S:
243 pgva = (vaddr_t)dst & L1_S_FRAME;
244 limit = L1_S_SIZE - ((vaddr_t)dst & L1_S_OFFSET);
245
246 tmppde = oldpde | L1_S_PROT_W;
247 *pde = tmppde;
248 PTE_SYNC(pde);
249 break;
250
251 case L1_TYPE_C:
252 pgva = (vaddr_t)dst & L2_S_FRAME;
253 limit = L2_S_SIZE - ((vaddr_t)dst & L2_S_OFFSET);
254
255 if (pte == NULL)
256 goto no_mapping;
257 oldpte = *pte;
258 tmppte = oldpte | L2_S_PROT_W;
259 *pte = tmppte;
260 PTE_SYNC(pte);
261 break;
262
263 default:
264 no_mapping:
265 printf(" address 0x%08lx not a valid page\n",
266 (vaddr_t) dst);
267 return;
268 }
269 cpu_tlb_flushD_SE(pgva);
270 cpu_cpwait();
271
272 if (limit > size)
273 limit = size;
274 size -= limit;
275
276 /*
277 * Page is now writable. Do as much access as we
278 * can in this page.
279 */
280 for (; limit > 0; limit--)
281 *dst++ = *data++;
282
283 /*
284 * Restore old mapping permissions.
285 */
286 switch (oldpde & L1_TYPE_MASK) {
287 case L1_TYPE_S:
288 *pde = oldpde;
289 PTE_SYNC(pde);
290 break;
291
292 case L1_TYPE_C:
293 *pte = oldpte;
294 PTE_SYNC(pte);
295 break;
296 }
297 cpu_tlb_flushD_SE(pgva);
298 cpu_cpwait();
299 } while (size != 0);
300
301 /* Sync the I-cache. */
302 cpu_icache_sync_range(addr, savesize);
303 }
304
305 /*
306 * Write bytes to kernel address space for debugger.
307 */
308 void
309 db_write_bytes(vaddr_t addr, size_t size, char *data)
310 {
311 extern char kernel_text[];
312 extern char etext[];
313 char *dst;
314 size_t loop;
315
316 /* If any part is in kernel text, use db_write_text() */
317 if (addr >= (vaddr_t) kernel_text && addr < (vaddr_t) etext) {
318 db_write_text(addr, size, data);
319 return;
320 }
321
322 dst = (char *)addr;
323 if (db_validate_address((u_int)dst)) {
324 db_printf("address %p is invalid\n", dst);
325 return;
326 }
327
328 if (size == 4 && (addr & 3) == 0 && ((uintptr_t)data & 3) == 0)
329 *((int*)dst) = *((int*)data);
330 else
331 if (size == 2 && (addr & 1) == 0 && ((uintptr_t)data & 1) == 0)
332 *((short*)dst) = *((short*)data);
333 else {
334 loop = size;
335 while (loop-- > 0) {
336 if (db_validate_address((u_int)dst)) {
337 db_printf("address %p is invalid\n", dst);
338 return;
339 }
340 *dst++ = *data++;
341 }
342 }
343
344 /* make sure the caches and memory are in sync */
345 cpu_icache_sync_range(addr, size);
346
347 /* In case the current page tables have been modified ... */
348 cpu_tlb_flushID();
349 cpu_cpwait();
350 }
351
352 #ifdef DDB
353 void
354 cpu_Debugger(void)
355 {
356 asm(".word 0xe7ffffff");
357 }
358
359 const struct db_command db_machine_command_table[] = {
360 { "frame", db_show_frame_cmd, 0, NULL },
361 { "panic", db_show_panic_cmd, 0, NULL },
362 #ifdef ARM32_DB_COMMANDS
363 ARM32_DB_COMMANDS,
364 #endif
365 { NULL, NULL, 0, NULL }
366 };
367
368 int
369 db_trapper(u_int addr, u_int inst, trapframe_t *frame, int fault_code)
370 {
371
372 if (fault_code == 0) {
373 if ((inst & ~INSN_COND_MASK) == (BKPT_INST & ~INSN_COND_MASK))
374 kdb_trap(T_BREAKPOINT, frame);
375 else
376 kdb_trap(-1, frame);
377 } else
378 return (1);
379 return (0);
380 }
381
382 extern u_int esym;
383 extern u_int end;
384
385 static struct undefined_handler db_uh;
386
387 void
388 db_machine_init(void)
389 {
390
391 /*
392 * We get called before malloc() is available, so supply a static
393 * struct undefined_handler.
394 */
395 db_uh.uh_handler = db_trapper;
396 install_coproc_handler_static(0, &db_uh);
397 }
398 #endif
399
400 u_int
401 db_fetch_reg(int reg, db_regs_t *db_regs)
402 {
403
404 switch (reg) {
405 case 0:
406 return (db_regs->tf_r0);
407 case 1:
408 return (db_regs->tf_r1);
409 case 2:
410 return (db_regs->tf_r2);
411 case 3:
412 return (db_regs->tf_r3);
413 case 4:
414 return (db_regs->tf_r4);
415 case 5:
416 return (db_regs->tf_r5);
417 case 6:
418 return (db_regs->tf_r6);
419 case 7:
420 return (db_regs->tf_r7);
421 case 8:
422 return (db_regs->tf_r8);
423 case 9:
424 return (db_regs->tf_r9);
425 case 10:
426 return (db_regs->tf_r10);
427 case 11:
428 return (db_regs->tf_r11);
429 case 12:
430 return (db_regs->tf_r12);
431 case 13:
432 return (db_regs->tf_svc_sp);
433 case 14:
434 return (db_regs->tf_svc_lr);
435 case 15:
436 return (db_regs->tf_pc);
437 default:
438 panic("db_fetch_reg: botch");
439 }
440 }
441
442 u_int
443 branch_taken(u_int insn, u_int pc, db_regs_t *db_regs)
444 {
445 u_int addr, nregs;
446
447 switch ((insn >> 24) & 0xf) {
448 case 0xa: /* b ... */
449 case 0xb: /* bl ... */
450 addr = ((insn << 2) & 0x03ffffff);
451 if (addr & 0x02000000)
452 addr |= 0xfc000000;
453 return (pc + 8 + addr);
454 case 0x7: /* ldr pc, [pc, reg, lsl #2] */
455 addr = db_fetch_reg(insn & 0xf, db_regs);
456 addr = pc + 8 + (addr << 2);
457 db_read_bytes(addr, 4, (char *)&addr);
458 return (addr);
459 case 0x1: /* mov pc, reg */
460 addr = db_fetch_reg(insn & 0xf, db_regs);
461 return (addr);
462 case 0x8: /* ldmxx reg, {..., pc} */
463 case 0x9:
464 addr = db_fetch_reg((insn >> 16) & 0xf, db_regs);
465 nregs = (insn & 0x5555) + ((insn >> 1) & 0x5555);
466 nregs = (nregs & 0x3333) + ((nregs >> 2) & 0x3333);
467 nregs = (nregs + (nregs >> 4)) & 0x0f0f;
468 nregs = (nregs + (nregs >> 8)) & 0x001f;
469 switch ((insn >> 23) & 0x3) {
470 case 0x0: /* ldmda */
471 addr = addr - 0;
472 break;
473 case 0x1: /* ldmia */
474 addr = addr + 0 + ((nregs - 1) << 2);
475 break;
476 case 0x2: /* ldmdb */
477 addr = addr - 4;
478 break;
479 case 0x3: /* ldmib */
480 addr = addr + 4 + ((nregs - 1) << 2);
481 break;
482 }
483 db_read_bytes(addr, 4, (char *)&addr);
484 return (addr);
485 default:
486 panic("branch_taken: botch");
487 }
488 }
489