db_interface.c revision 1.29 1 /* $NetBSD: db_interface.c,v 1.29 2003/05/21 18:04:42 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 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;
197
198 src = (char *)addr;
199
200 while (size-- > 0) {
201 if (db_validate_address((u_int)src)) {
202 db_printf("address %p is invalid\n", src);
203 return;
204 }
205 *data++ = *src++;
206 }
207 }
208
209 static void
210 db_write_text(vaddr_t addr, size_t size, char *data)
211 {
212 struct pmap *pmap = pmap_kernel();
213 pd_entry_t *pde, oldpde, tmppde;
214 pt_entry_t *pte, oldpte, tmppte;
215 vaddr_t pgva;
216 size_t limit, savesize;
217 char *dst;
218
219 if ((savesize = size) == 0)
220 return;
221
222 dst = (char *) addr;
223
224 do {
225 /* Get the PDE of the current VA. */
226 if (pmap_get_pde_pte(pmap, (vaddr_t) dst, &pde, &pte) == FALSE)
227 goto no_mapping;
228 switch ((oldpde = *pde) & L1_TYPE_MASK) {
229 case L1_TYPE_S:
230 pgva = (vaddr_t)dst & L1_S_FRAME;
231 limit = L1_S_SIZE - ((vaddr_t)dst & L1_S_OFFSET);
232
233 tmppde = oldpde | L1_S_PROT_W;
234 *pde = tmppde;
235 PTE_SYNC(pde);
236 break;
237
238 case L1_TYPE_C:
239 pgva = (vaddr_t)dst & L2_S_FRAME;
240 limit = L2_S_SIZE - ((vaddr_t)dst & L2_S_OFFSET);
241
242 if (pte == NULL)
243 goto no_mapping;
244 oldpte = *pte;
245 tmppte = oldpte | L2_S_PROT_W;
246 *pte = tmppte;
247 PTE_SYNC(pte);
248 break;
249
250 default:
251 no_mapping:
252 printf(" address 0x%08lx not a valid page\n",
253 (vaddr_t) dst);
254 return;
255 }
256 cpu_tlb_flushD_SE(pgva);
257 cpu_cpwait();
258
259 if (limit > size)
260 limit = size;
261 size -= limit;
262
263 /*
264 * Page is now writable. Do as much access as we
265 * can in this page.
266 */
267 for (; limit > 0; limit--)
268 *dst++ = *data++;
269
270 /*
271 * Restore old mapping permissions.
272 */
273 switch (oldpde & L1_TYPE_MASK) {
274 case L1_TYPE_S:
275 *pde = oldpde;
276 PTE_SYNC(pde);
277 break;
278
279 case L1_TYPE_C:
280 *pte = oldpte;
281 PTE_SYNC(pte);
282 break;
283 }
284 cpu_tlb_flushD_SE(pgva);
285 cpu_cpwait();
286 } while (size != 0);
287
288 /* Sync the I-cache. */
289 cpu_icache_sync_range(addr, savesize);
290 }
291
292 /*
293 * Write bytes to kernel address space for debugger.
294 */
295 void
296 db_write_bytes(vaddr_t addr, size_t size, char *data)
297 {
298 extern char kernel_text[];
299 extern char etext[];
300 char *dst;
301 size_t loop;
302
303 /* If any part is in kernel text, use db_write_text() */
304 if (addr >= (vaddr_t) kernel_text && addr < (vaddr_t) etext) {
305 db_write_text(addr, size, data);
306 return;
307 }
308
309 dst = (char *)addr;
310 loop = size;
311 while (loop-- > 0) {
312 if (db_validate_address((u_int)dst)) {
313 db_printf("address %p is invalid\n", dst);
314 return;
315 }
316 *dst++ = *data++;
317 }
318 /* make sure the caches and memory are in sync */
319 cpu_icache_sync_range(addr, size);
320
321 /* In case the current page tables have been modified ... */
322 cpu_tlb_flushID();
323 cpu_cpwait();
324 }
325
326 #ifdef DDB
327 void
328 cpu_Debugger(void)
329 {
330 asm(".word 0xe7ffffff");
331 }
332
333 const struct db_command db_machine_command_table[] = {
334 { "frame", db_show_frame_cmd, 0, NULL },
335 { "panic", db_show_panic_cmd, 0, NULL },
336 #ifdef ARM32_DB_COMMANDS
337 ARM32_DB_COMMANDS,
338 #endif
339 { NULL, NULL, 0, NULL }
340 };
341
342 int
343 db_trapper(u_int addr, u_int inst, trapframe_t *frame, int fault_code)
344 {
345
346 if (fault_code == 0) {
347 if ((inst & ~INSN_COND_MASK) == (BKPT_INST & ~INSN_COND_MASK))
348 kdb_trap(T_BREAKPOINT, frame);
349 else
350 kdb_trap(-1, frame);
351 } else
352 return (1);
353 return (0);
354 }
355
356 extern u_int esym;
357 extern u_int end;
358
359 static struct undefined_handler db_uh;
360
361 void
362 db_machine_init(void)
363 {
364
365 /*
366 * We get called before malloc() is available, so supply a static
367 * struct undefined_handler.
368 */
369 db_uh.uh_handler = db_trapper;
370 install_coproc_handler_static(0, &db_uh);
371 }
372 #endif
373
374 u_int
375 db_fetch_reg(int reg, db_regs_t *db_regs)
376 {
377
378 switch (reg) {
379 case 0:
380 return (db_regs->tf_r0);
381 case 1:
382 return (db_regs->tf_r1);
383 case 2:
384 return (db_regs->tf_r2);
385 case 3:
386 return (db_regs->tf_r3);
387 case 4:
388 return (db_regs->tf_r4);
389 case 5:
390 return (db_regs->tf_r5);
391 case 6:
392 return (db_regs->tf_r6);
393 case 7:
394 return (db_regs->tf_r7);
395 case 8:
396 return (db_regs->tf_r8);
397 case 9:
398 return (db_regs->tf_r9);
399 case 10:
400 return (db_regs->tf_r10);
401 case 11:
402 return (db_regs->tf_r11);
403 case 12:
404 return (db_regs->tf_r12);
405 case 13:
406 return (db_regs->tf_svc_sp);
407 case 14:
408 return (db_regs->tf_svc_lr);
409 case 15:
410 return (db_regs->tf_pc);
411 default:
412 panic("db_fetch_reg: botch");
413 }
414 }
415
416 u_int
417 branch_taken(u_int insn, u_int pc, db_regs_t *db_regs)
418 {
419 u_int addr, nregs;
420
421 switch ((insn >> 24) & 0xf) {
422 case 0xa: /* b ... */
423 case 0xb: /* bl ... */
424 addr = ((insn << 2) & 0x03ffffff);
425 if (addr & 0x02000000)
426 addr |= 0xfc000000;
427 return (pc + 8 + addr);
428 case 0x7: /* ldr pc, [pc, reg, lsl #2] */
429 addr = db_fetch_reg(insn & 0xf, db_regs);
430 addr = pc + 8 + (addr << 2);
431 db_read_bytes(addr, 4, (char *)&addr);
432 return (addr);
433 case 0x1: /* mov pc, reg */
434 addr = db_fetch_reg(insn & 0xf, db_regs);
435 return (addr);
436 case 0x8: /* ldmxx reg, {..., pc} */
437 case 0x9:
438 addr = db_fetch_reg((insn >> 16) & 0xf, db_regs);
439 nregs = (insn & 0x5555) + ((insn >> 1) & 0x5555);
440 nregs = (nregs & 0x3333) + ((nregs >> 2) & 0x3333);
441 nregs = (nregs + (nregs >> 4)) & 0x0f0f;
442 nregs = (nregs + (nregs >> 8)) & 0x001f;
443 switch ((insn >> 23) & 0x3) {
444 case 0x0: /* ldmda */
445 addr = addr - 0;
446 break;
447 case 0x1: /* ldmia */
448 addr = addr + 0 + ((nregs - 1) << 2);
449 break;
450 case 0x2: /* ldmdb */
451 addr = addr - 4;
452 break;
453 case 0x3: /* ldmib */
454 addr = addr + 4 + ((nregs - 1) << 2);
455 break;
456 }
457 db_read_bytes(addr, 4, (char *)&addr);
458 return (addr);
459 default:
460 panic("branch_taken: botch");
461 }
462 }
463