db_interface.c revision 1.27 1 /* $NetBSD: db_interface.c,v 1.27 2003/05/03 17:32:59 thorpej 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 #ifndef ARM32_PMAP_NEW
174 if (!p || !p->p_vmspace || !p->p_vmspace->vm_map.pmap)
175 #else
176 if (!p || !p->p_vmspace || !p->p_vmspace->vm_map.pmap ||
177 #ifndef ARM32_NEW_VM_LAYOUT
178 addr >= VM_MAXUSER_ADDRESS)
179 #else
180 addr >= VM_MIN_KERNEL_ADDRESS)
181 #endif
182 #endif
183 pmap = pmap_kernel();
184 else
185 pmap = p->p_vmspace->vm_map.pmap;
186
187 return (pmap_extract(pmap, addr, NULL) == FALSE);
188 }
189
190 /*
191 * Read bytes from kernel address space for debugger.
192 */
193 void
194 db_read_bytes(addr, size, data)
195 vaddr_t addr;
196 size_t size;
197 char *data;
198 {
199 char *src;
200
201 src = (char *)addr;
202
203 while (size-- > 0) {
204 if (db_validate_address((u_int)src)) {
205 db_printf("address %p is invalid\n", src);
206 return;
207 }
208 *data++ = *src++;
209 }
210 }
211
212 static void
213 db_write_text(vaddr_t addr, size_t size, char *data)
214 {
215 struct pmap *pmap = pmap_kernel();
216 pd_entry_t *pde, oldpde, tmppde;
217 pt_entry_t *pte, oldpte, tmppte;
218 vaddr_t pgva;
219 size_t limit, savesize;
220 char *dst;
221
222 if ((savesize = size) == 0)
223 return;
224
225 dst = (char *) addr;
226
227 do {
228 /* Get the PDE of the current VA. */
229 #ifndef ARM32_PMAP_NEW
230 pde = pmap_pde(pmap, (vaddr_t) dst);
231 #else
232 if (pmap_get_pde_pte(pmap, (vaddr_t) dst, &pde, &pte) == FALSE)
233 goto no_mapping;
234 #endif
235 switch ((oldpde = *pde) & L1_TYPE_MASK) {
236 case L1_TYPE_S:
237 pgva = (vaddr_t)dst & L1_S_FRAME;
238 limit = L1_S_SIZE - ((vaddr_t)dst & L1_S_OFFSET);
239
240 tmppde = oldpde | L1_S_PROT_W;
241 *pde = tmppde;
242 PTE_SYNC(pde);
243 break;
244
245 case L1_TYPE_C:
246 pgva = (vaddr_t)dst & L2_S_FRAME;
247 limit = L2_S_SIZE - ((vaddr_t)dst & L2_S_OFFSET);
248
249 #ifndef ARM32_PMAP_NEW
250 pte = vtopte(pgva);
251 #else
252 if (pte == NULL)
253 goto no_mapping;
254 #endif
255 oldpte = *pte;
256 tmppte = oldpte | L2_S_PROT_W;
257 *pte = tmppte;
258 PTE_SYNC(pte);
259 break;
260
261 default:
262 #ifdef ARM32_PMAP_NEW
263 no_mapping:
264 #endif
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 loop = size;
324 while (loop-- > 0) {
325 if (db_validate_address((u_int)dst)) {
326 db_printf("address %p is invalid\n", dst);
327 return;
328 }
329 *dst++ = *data++;
330 }
331 /* make sure the caches and memory are in sync */
332 cpu_icache_sync_range(addr, size);
333
334 /* In case the current page tables have been modified ... */
335 cpu_tlb_flushID();
336 cpu_cpwait();
337 }
338
339 void
340 cpu_Debugger(void)
341 {
342 asm(".word 0xe7ffffff");
343 }
344
345 #ifdef DDB
346 const struct db_command db_machine_command_table[] = {
347 { "frame", db_show_frame_cmd, 0, NULL },
348 { "panic", db_show_panic_cmd, 0, NULL },
349 #ifdef ARM32_DB_COMMANDS
350 ARM32_DB_COMMANDS,
351 #endif
352 { NULL, NULL, 0, NULL }
353 };
354
355 int
356 db_trapper(u_int addr, u_int inst, trapframe_t *frame, int fault_code)
357 {
358
359 if (fault_code == 0) {
360 if ((inst & ~INSN_COND_MASK) == (BKPT_INST & ~INSN_COND_MASK))
361 kdb_trap(T_BREAKPOINT, frame);
362 else
363 kdb_trap(-1, frame);
364 } else
365 return (1);
366 return (0);
367 }
368
369 extern u_int esym;
370 extern u_int end;
371
372 static struct undefined_handler db_uh;
373
374 void
375 db_machine_init(void)
376 {
377
378 /*
379 * We get called before malloc() is available, so supply a static
380 * struct undefined_handler.
381 */
382 db_uh.uh_handler = db_trapper;
383 install_coproc_handler_static(0, &db_uh);
384 }
385 #endif
386
387 u_int
388 db_fetch_reg(int reg, db_regs_t *db_regs)
389 {
390
391 switch (reg) {
392 case 0:
393 return (db_regs->tf_r0);
394 case 1:
395 return (db_regs->tf_r1);
396 case 2:
397 return (db_regs->tf_r2);
398 case 3:
399 return (db_regs->tf_r3);
400 case 4:
401 return (db_regs->tf_r4);
402 case 5:
403 return (db_regs->tf_r5);
404 case 6:
405 return (db_regs->tf_r6);
406 case 7:
407 return (db_regs->tf_r7);
408 case 8:
409 return (db_regs->tf_r8);
410 case 9:
411 return (db_regs->tf_r9);
412 case 10:
413 return (db_regs->tf_r10);
414 case 11:
415 return (db_regs->tf_r11);
416 case 12:
417 return (db_regs->tf_r12);
418 case 13:
419 return (db_regs->tf_svc_sp);
420 case 14:
421 return (db_regs->tf_svc_lr);
422 case 15:
423 return (db_regs->tf_pc);
424 default:
425 panic("db_fetch_reg: botch");
426 }
427 }
428
429 u_int
430 branch_taken(u_int insn, u_int pc, db_regs_t *db_regs)
431 {
432 u_int addr, nregs;
433
434 switch ((insn >> 24) & 0xf) {
435 case 0xa: /* b ... */
436 case 0xb: /* bl ... */
437 addr = ((insn << 2) & 0x03ffffff);
438 if (addr & 0x02000000)
439 addr |= 0xfc000000;
440 return (pc + 8 + addr);
441 case 0x7: /* ldr pc, [pc, reg, lsl #2] */
442 addr = db_fetch_reg(insn & 0xf, db_regs);
443 addr = pc + 8 + (addr << 2);
444 db_read_bytes(addr, 4, (char *)&addr);
445 return (addr);
446 case 0x1: /* mov pc, reg */
447 addr = db_fetch_reg(insn & 0xf, db_regs);
448 return (addr);
449 case 0x8: /* ldmxx reg, {..., pc} */
450 case 0x9:
451 addr = db_fetch_reg((insn >> 16) & 0xf, db_regs);
452 nregs = (insn & 0x5555) + ((insn >> 1) & 0x5555);
453 nregs = (nregs & 0x3333) + ((nregs >> 2) & 0x3333);
454 nregs = (nregs + (nregs >> 4)) & 0x0f0f;
455 nregs = (nregs + (nregs >> 8)) & 0x001f;
456 switch ((insn >> 23) & 0x3) {
457 case 0x0: /* ldmda */
458 addr = addr - 0;
459 break;
460 case 0x1: /* ldmia */
461 addr = addr + 0 + ((nregs - 1) << 2);
462 break;
463 case 0x2: /* ldmdb */
464 addr = addr - 4;
465 break;
466 case 0x3: /* ldmib */
467 addr = addr + 4 + ((nregs - 1) << 2);
468 break;
469 }
470 db_read_bytes(addr, 4, (char *)&addr);
471 return (addr);
472 default:
473 panic("branch_taken: botch");
474 }
475 }
476