db_interface.c revision 1.15
1 /* $NetBSD: db_interface.c,v 1.15 2002/01/17 20:47:00 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 38 #include <sys/param.h> 39 #include <sys/proc.h> 40 #include <sys/reboot.h> 41 #include <sys/systm.h> /* just for boothowto */ 42 #include <sys/exec.h> 43 44 #include <uvm/uvm_extern.h> 45 46 #include <arm/arm32/db_machdep.h> 47 #include <arm/arm32/katelib.h> 48 #include <arm/undefined.h> 49 #include <ddb/db_access.h> 50 #include <ddb/db_command.h> 51 #include <ddb/db_output.h> 52 #include <ddb/db_variables.h> 53 #include <ddb/db_sym.h> 54 #include <ddb/db_extern.h> 55 #include <ddb/db_interface.h> 56 #include <dev/cons.h> 57 58 static int nil; 59 60 int db_access_und_sp __P((const struct db_variable *, db_expr_t *, int)); 61 int db_access_abt_sp __P((const struct db_variable *, db_expr_t *, int)); 62 int db_access_irq_sp __P((const struct db_variable *, db_expr_t *, int)); 63 u_int db_fetch_reg __P((int, db_regs_t *)); 64 65 int db_trapper __P((u_int, u_int, trapframe_t *, int)); 66 67 const struct db_variable db_regs[] = { 68 { "spsr", (long *)&DDB_REGS->tf_spsr, FCN_NULL, }, 69 { "r0", (long *)&DDB_REGS->tf_r0, FCN_NULL, }, 70 { "r1", (long *)&DDB_REGS->tf_r1, FCN_NULL, }, 71 { "r2", (long *)&DDB_REGS->tf_r2, FCN_NULL, }, 72 { "r3", (long *)&DDB_REGS->tf_r3, FCN_NULL, }, 73 { "r4", (long *)&DDB_REGS->tf_r4, FCN_NULL, }, 74 { "r5", (long *)&DDB_REGS->tf_r5, FCN_NULL, }, 75 { "r6", (long *)&DDB_REGS->tf_r6, FCN_NULL, }, 76 { "r7", (long *)&DDB_REGS->tf_r7, FCN_NULL, }, 77 { "r8", (long *)&DDB_REGS->tf_r8, FCN_NULL, }, 78 { "r9", (long *)&DDB_REGS->tf_r9, FCN_NULL, }, 79 { "r10", (long *)&DDB_REGS->tf_r10, FCN_NULL, }, 80 { "r11", (long *)&DDB_REGS->tf_r11, FCN_NULL, }, 81 { "r12", (long *)&DDB_REGS->tf_r12, FCN_NULL, }, 82 { "usr_sp", (long *)&DDB_REGS->tf_usr_sp, FCN_NULL, }, 83 { "usr_lr", (long *)&DDB_REGS->tf_usr_lr, FCN_NULL, }, 84 { "svc_sp", (long *)&DDB_REGS->tf_svc_sp, FCN_NULL, }, 85 { "svc_lr", (long *)&DDB_REGS->tf_svc_lr, FCN_NULL, }, 86 { "pc", (long *)&DDB_REGS->tf_pc, FCN_NULL, }, 87 { "und_sp", (long *)&nil, db_access_und_sp, }, 88 { "abt_sp", (long *)&nil, db_access_abt_sp, }, 89 { "irq_sp", (long *)&nil, db_access_irq_sp, }, 90 }; 91 92 const struct db_variable * const db_eregs = db_regs + sizeof(db_regs)/sizeof(db_regs[0]); 93 94 extern label_t *db_recover; 95 96 int db_active = 0; 97 98 int 99 db_access_und_sp(const struct db_variable *vp, db_expr_t *valp, int rw) 100 { 101 102 if (rw == DB_VAR_GET) 103 *valp = get_stackptr(PSR_UND32_MODE); 104 return(0); 105 } 106 107 int 108 db_access_abt_sp(const struct db_variable *vp, db_expr_t *valp, int rw) 109 { 110 111 if (rw == DB_VAR_GET) 112 *valp = get_stackptr(PSR_ABT32_MODE); 113 return(0); 114 } 115 116 int 117 db_access_irq_sp(const struct db_variable *vp, db_expr_t *valp, int rw) 118 { 119 120 if (rw == DB_VAR_GET) 121 *valp = get_stackptr(PSR_IRQ32_MODE); 122 return(0); 123 } 124 125 /* 126 * kdb_trap - field a TRACE or BPT trap 127 */ 128 int 129 kdb_trap(int type, db_regs_t *regs) 130 { 131 int s; 132 133 switch (type) { 134 case T_BREAKPOINT: /* breakpoint */ 135 case -1: /* keyboard interrupt */ 136 break; 137 default: 138 db_printf("kernel: trap"); 139 if (db_recover != 0) { 140 db_error("Faulted in DDB; continuing...\n"); 141 /*NOTREACHED*/ 142 } 143 } 144 145 /* Should switch to kdb`s own stack here. */ 146 147 ddb_regs = *regs; 148 149 s = splhigh(); 150 db_active++; 151 cnpollc(TRUE); 152 db_trap(type, 0/*code*/); 153 cnpollc(FALSE); 154 db_active--; 155 splx(s); 156 157 *regs = ddb_regs; 158 159 return (1); 160 } 161 162 163 static int 164 db_validate_address(vaddr_t addr) 165 { 166 struct proc *p = curproc; 167 struct pmap *pmap; 168 169 if (!p || !p->p_vmspace || !p->p_vmspace->vm_map.pmap) 170 pmap = pmap_kernel(); 171 else 172 pmap = p->p_vmspace->vm_map.pmap; 173 174 return (pmap_extract(pmap, addr, NULL) == FALSE); 175 } 176 177 /* 178 * Read bytes from kernel address space for debugger. 179 */ 180 void 181 db_read_bytes(addr, size, data) 182 vm_offset_t addr; 183 size_t size; 184 char *data; 185 { 186 char *src; 187 188 src = (char *)addr; 189 190 while (size-- > 0) { 191 if (db_validate_address((u_int)src)) { 192 db_printf("address %p is invalid\n", src); 193 return; 194 } 195 *data++ = *src++; 196 } 197 } 198 199 static void 200 db_write_text(vaddr_t addr, size_t size, char *data) 201 { 202 struct pmap *pmap = pmap_kernel(); 203 pd_entry_t *pde, oldpde, tmppde; 204 pt_entry_t *pte, oldpte, tmppte; 205 vaddr_t pgva; 206 size_t limit, savesize; 207 char *dst; 208 209 if ((savesize = size) == 0) 210 return; 211 212 dst = (char *) addr; 213 214 do { 215 /* Get the PDE of the current VA. */ 216 pde = pmap_pde(pmap, (vaddr_t) dst); 217 switch ((oldpde = *pde) & L1_MASK) { 218 case L1_SECTION: 219 pgva = (vaddr_t)dst & ~(L1_SEC_SIZE - 1); 220 limit = L1_SEC_SIZE - 221 ((vaddr_t)dst & (L1_SEC_SIZE - 1)); 222 223 tmppde = oldpde | (AP_KRW << AP_SECTION_SHIFT); 224 *pde = tmppde; 225 break; 226 227 case L1_PAGE: 228 pgva = (vaddr_t)dst & ~PGOFSET; 229 limit = NBPG - ((vaddr_t)dst & PGOFSET); 230 231 pte = vtopte(pgva); 232 oldpte = *pte; 233 tmppte = oldpte | PT_AP(AP_KRW); 234 *pte = tmppte; 235 break; 236 237 default: 238 printf(" address 0x%08lx not a valid page\n", 239 (vaddr_t) dst); 240 return; 241 } 242 cpu_tlb_flushD_SE(pgva); 243 244 if (limit > size) 245 limit = size; 246 size -= limit; 247 248 /* 249 * Page is now writable. Do as much access as we 250 * can in this page. 251 */ 252 for (; limit > 0; limit--) 253 *dst++ = *data++; 254 255 /* 256 * Restore old mapping permissions. 257 */ 258 switch (oldpde & L1_MASK) { 259 case L1_SECTION: 260 *pde = oldpde; 261 break; 262 263 case L1_PAGE: 264 *pte = oldpte; 265 break; 266 } 267 cpu_tlb_flushD_SE(pgva); 268 } while (size != 0); 269 270 /* Sync the I-cache. */ 271 cpu_cache_syncI_rng(addr, savesize); 272 } 273 274 /* 275 * Write bytes to kernel address space for debugger. 276 */ 277 void 278 db_write_bytes(vaddr_t addr, size_t size, char *data) 279 { 280 extern char etext[]; 281 char *dst; 282 size_t loop; 283 284 /* If any part is in kernel text, use db_write_text() */ 285 if (addr >= KERNEL_TEXT_BASE && addr < (vaddr_t) etext) { 286 db_write_text(addr, size, data); 287 return; 288 } 289 290 dst = (char *)addr; 291 loop = size; 292 while (loop-- > 0) { 293 if (db_validate_address((u_int)dst)) { 294 db_printf("address %p is invalid\n", dst); 295 return; 296 } 297 *dst++ = *data++; 298 } 299 /* make sure the caches and memory are in sync */ 300 cpu_cache_syncI_rng(addr, size); 301 302 /* In case the current page tables have been modified ... */ 303 cpu_tlb_flushID(); 304 } 305 306 void 307 cpu_Debugger(void) 308 { 309 asm(".word 0xe7ffffff"); 310 } 311 312 const struct db_command db_machine_command_table[] = { 313 { "frame", db_show_frame_cmd, 0, NULL }, 314 { "panic", db_show_panic_cmd, 0, NULL }, 315 #ifdef ARM32_DB_COMMANDS 316 ARM32_DB_COMMANDS, 317 #endif 318 { NULL, NULL, 0, NULL } 319 }; 320 321 int 322 db_trapper(u_int addr, u_int inst, trapframe_t *frame, int fault_code) 323 { 324 325 if (fault_code == 0) { 326 if ((inst & ~INSN_COND_MASK) == (BKPT_INST & ~INSN_COND_MASK)) 327 kdb_trap(T_BREAKPOINT, frame); 328 else 329 kdb_trap(-1, frame); 330 } else 331 return (1); 332 return (0); 333 } 334 335 extern u_int esym; 336 extern u_int end; 337 338 static struct undefined_handler db_uh; 339 340 void 341 db_machine_init(void) 342 { 343 #ifndef __ELF__ 344 struct exec *kernexec = (struct exec *)KERNEL_TEXT_BASE; 345 int len; 346 347 /* 348 * The boot loader currently loads the kernel with the a.out 349 * header still attached. 350 */ 351 352 if (kernexec->a_syms == 0) { 353 printf("ddb: No symbol table\n"); 354 } else { 355 /* cover the symbols themselves (what is the int for?? XXX) */ 356 esym = (int)&end + kernexec->a_syms + sizeof(int); 357 358 /* 359 * and the string table. (int containing size of string 360 * table is included in string table size). 361 */ 362 len = *((u_int *)esym); 363 esym += (len + (sizeof(u_int) - 1)) & ~(sizeof(u_int) - 1); 364 } 365 #endif 366 367 /* 368 * We get called before malloc() is available, so supply a static 369 * struct undefined_handler. 370 */ 371 db_uh.uh_handler = db_trapper; 372 install_coproc_handler_static(0, &db_uh); 373 } 374 375 u_int 376 db_fetch_reg(int reg, db_regs_t *db_regs) 377 { 378 379 switch (reg) { 380 case 0: 381 return (db_regs->tf_r0); 382 case 1: 383 return (db_regs->tf_r1); 384 case 2: 385 return (db_regs->tf_r2); 386 case 3: 387 return (db_regs->tf_r3); 388 case 4: 389 return (db_regs->tf_r4); 390 case 5: 391 return (db_regs->tf_r5); 392 case 6: 393 return (db_regs->tf_r6); 394 case 7: 395 return (db_regs->tf_r7); 396 case 8: 397 return (db_regs->tf_r8); 398 case 9: 399 return (db_regs->tf_r9); 400 case 10: 401 return (db_regs->tf_r10); 402 case 11: 403 return (db_regs->tf_r11); 404 case 12: 405 return (db_regs->tf_r12); 406 case 13: 407 return (db_regs->tf_svc_sp); 408 case 14: 409 return (db_regs->tf_svc_lr); 410 case 15: 411 return (db_regs->tf_pc); 412 default: 413 panic("db_fetch_reg: botch"); 414 } 415 } 416 417 u_int 418 branch_taken(u_int insn, u_int pc, db_regs_t *db_regs) 419 { 420 u_int addr, nregs; 421 422 switch ((insn >> 24) & 0xf) { 423 case 0xa: /* b ... */ 424 case 0xb: /* bl ... */ 425 addr = ((insn << 2) & 0x03ffffff); 426 if (addr & 0x02000000) 427 addr |= 0xfc000000; 428 return (pc + 8 + addr); 429 case 0x7: /* ldr pc, [pc, reg, lsl #2] */ 430 addr = db_fetch_reg(insn & 0xf, db_regs); 431 addr = pc + 8 + (addr << 2); 432 db_read_bytes(addr, 4, (char *)&addr); 433 return (addr); 434 case 0x1: /* mov pc, reg */ 435 addr = db_fetch_reg(insn & 0xf, db_regs); 436 return (addr); 437 case 0x8: /* ldmxx reg, {..., pc} */ 438 case 0x9: 439 addr = db_fetch_reg((insn >> 16) & 0xf, db_regs); 440 nregs = (insn & 0x5555) + ((insn >> 1) & 0x5555); 441 nregs = (nregs & 0x3333) + ((nregs >> 2) & 0x3333); 442 nregs = (nregs + (nregs >> 4)) & 0x0f0f; 443 nregs = (nregs + (nregs >> 8)) & 0x001f; 444 switch ((insn >> 23) & 0x3) { 445 case 0x0: /* ldmda */ 446 addr = addr - 0; 447 break; 448 case 0x1: /* ldmia */ 449 addr = addr + 0 + ((nregs - 1) << 2); 450 break; 451 case 0x2: /* ldmdb */ 452 addr = addr - 4; 453 break; 454 case 0x3: /* ldmib */ 455 addr = addr + 4 + ((nregs - 1) << 2); 456 break; 457 } 458 db_read_bytes(addr, 4, (char *)&addr); 459 return (addr); 460 default: 461 panic("branch_taken: botch"); 462 } 463 } 464
Indexes created Tue Sep 30 11:09:46 GMT 2025