db_interface.c revision 1.22
1 /* $NetBSD: db_interface.c,v 1.22 2002/08/22 01:13:55 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 int db_active = 0; 95 96 int 97 db_access_und_sp(const struct db_variable *vp, db_expr_t *valp, int rw) 98 { 99 100 if (rw == DB_VAR_GET) 101 *valp = get_stackptr(PSR_UND32_MODE); 102 return(0); 103 } 104 105 int 106 db_access_abt_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_ABT32_MODE); 111 return(0); 112 } 113 114 int 115 db_access_irq_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_IRQ32_MODE); 120 return(0); 121 } 122 123 /* 124 * kdb_trap - field a TRACE or BPT trap 125 */ 126 int 127 kdb_trap(int type, db_regs_t *regs) 128 { 129 int s; 130 131 switch (type) { 132 case T_BREAKPOINT: /* breakpoint */ 133 case -1: /* keyboard interrupt */ 134 break; 135 default: 136 db_printf("kernel: trap"); 137 if (db_recover != 0) { 138 db_error("Faulted in DDB; continuing...\n"); 139 /*NOTREACHED*/ 140 } 141 } 142 143 /* Should switch to kdb`s own stack here. */ 144 145 ddb_regs = *regs; 146 147 s = splhigh(); 148 db_active++; 149 cnpollc(TRUE); 150 db_trap(type, 0/*code*/); 151 cnpollc(FALSE); 152 db_active--; 153 splx(s); 154 155 *regs = ddb_regs; 156 157 return (1); 158 } 159 160 161 static int 162 db_validate_address(vaddr_t addr) 163 { 164 struct proc *p = curproc; 165 struct pmap *pmap; 166 167 if (!p || !p->p_vmspace || !p->p_vmspace->vm_map.pmap) 168 pmap = pmap_kernel(); 169 else 170 pmap = p->p_vmspace->vm_map.pmap; 171 172 return (pmap_extract(pmap, addr, NULL) == FALSE); 173 } 174 175 /* 176 * Read bytes from kernel address space for debugger. 177 */ 178 void 179 db_read_bytes(addr, size, data) 180 vaddr_t addr; 181 size_t size; 182 char *data; 183 { 184 char *src; 185 186 src = (char *)addr; 187 188 while (size-- > 0) { 189 if (db_validate_address((u_int)src)) { 190 db_printf("address %p is invalid\n", src); 191 return; 192 } 193 *data++ = *src++; 194 } 195 } 196 197 static void 198 db_write_text(vaddr_t addr, size_t size, char *data) 199 { 200 struct pmap *pmap = pmap_kernel(); 201 pd_entry_t *pde, oldpde, tmppde; 202 pt_entry_t *pte, oldpte, tmppte; 203 vaddr_t pgva; 204 size_t limit, savesize; 205 char *dst; 206 207 if ((savesize = size) == 0) 208 return; 209 210 dst = (char *) addr; 211 212 do { 213 /* Get the PDE of the current VA. */ 214 pde = pmap_pde(pmap, (vaddr_t) dst); 215 switch ((oldpde = *pde) & L1_TYPE_MASK) { 216 case L1_TYPE_S: 217 pgva = (vaddr_t)dst & L1_S_FRAME; 218 limit = L1_S_SIZE - ((vaddr_t)dst & L1_S_OFFSET); 219 220 tmppde = oldpde | L1_S_PROT_W; 221 *pde = tmppde; 222 PTE_SYNC(pde); 223 break; 224 225 case L1_TYPE_C: 226 pgva = (vaddr_t)dst & L2_S_FRAME; 227 limit = L2_S_SIZE - ((vaddr_t)dst & L2_S_OFFSET); 228 229 pte = vtopte(pgva); 230 oldpte = *pte; 231 tmppte = oldpte | L2_S_PROT_W; 232 *pte = tmppte; 233 PTE_SYNC(pte); 234 break; 235 236 default: 237 printf(" address 0x%08lx not a valid page\n", 238 (vaddr_t) dst); 239 return; 240 } 241 cpu_tlb_flushD_SE(pgva); 242 cpu_cpwait(); 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_TYPE_MASK) { 259 case L1_TYPE_S: 260 *pde = oldpde; 261 PTE_SYNC(pde); 262 break; 263 264 case L1_TYPE_C: 265 *pte = oldpte; 266 PTE_SYNC(pte); 267 break; 268 } 269 cpu_tlb_flushD_SE(pgva); 270 cpu_cpwait(); 271 } while (size != 0); 272 273 /* Sync the I-cache. */ 274 cpu_icache_sync_range(addr, savesize); 275 } 276 277 /* 278 * Write bytes to kernel address space for debugger. 279 */ 280 void 281 db_write_bytes(vaddr_t addr, size_t size, char *data) 282 { 283 extern char etext[]; 284 char *dst; 285 size_t loop; 286 287 /* If any part is in kernel text, use db_write_text() */ 288 if (addr >= KERNEL_TEXT_BASE && addr < (vaddr_t) etext) { 289 db_write_text(addr, size, data); 290 return; 291 } 292 293 dst = (char *)addr; 294 loop = size; 295 while (loop-- > 0) { 296 if (db_validate_address((u_int)dst)) { 297 db_printf("address %p is invalid\n", dst); 298 return; 299 } 300 *dst++ = *data++; 301 } 302 /* make sure the caches and memory are in sync */ 303 cpu_icache_sync_range(addr, size); 304 305 /* In case the current page tables have been modified ... */ 306 cpu_tlb_flushID(); 307 cpu_cpwait(); 308 } 309 310 void 311 cpu_Debugger(void) 312 { 313 asm(".word 0xe7ffffff"); 314 } 315 316 const struct db_command db_machine_command_table[] = { 317 { "frame", db_show_frame_cmd, 0, NULL }, 318 { "panic", db_show_panic_cmd, 0, NULL }, 319 #ifdef ARM32_DB_COMMANDS 320 ARM32_DB_COMMANDS, 321 #endif 322 { NULL, NULL, 0, NULL } 323 }; 324 325 int 326 db_trapper(u_int addr, u_int inst, trapframe_t *frame, int fault_code) 327 { 328 329 if (fault_code == 0) { 330 if ((inst & ~INSN_COND_MASK) == (BKPT_INST & ~INSN_COND_MASK)) 331 kdb_trap(T_BREAKPOINT, frame); 332 else 333 kdb_trap(-1, frame); 334 } else 335 return (1); 336 return (0); 337 } 338 339 extern u_int esym; 340 extern u_int end; 341 342 static struct undefined_handler db_uh; 343 344 void 345 db_machine_init(void) 346 { 347 #ifndef __ELF__ 348 struct exec *kernexec = (struct exec *)KERNEL_TEXT_BASE; 349 int len; 350 351 /* 352 * The boot loader currently loads the kernel with the a.out 353 * header still attached. 354 */ 355 356 if (kernexec->a_syms == 0) { 357 printf("ddb: No symbol table\n"); 358 } else { 359 /* cover the symbols themselves (what is the int for?? XXX) */ 360 esym = (int)&end + kernexec->a_syms + sizeof(int); 361 362 /* 363 * and the string table. (int containing size of string 364 * table is included in string table size). 365 */ 366 len = *((u_int *)esym); 367 esym += (len + (sizeof(u_int) - 1)) & ~(sizeof(u_int) - 1); 368 } 369 #endif 370 371 /* 372 * We get called before malloc() is available, so supply a static 373 * struct undefined_handler. 374 */ 375 db_uh.uh_handler = db_trapper; 376 install_coproc_handler_static(0, &db_uh); 377 } 378 379 u_int 380 db_fetch_reg(int reg, db_regs_t *db_regs) 381 { 382 383 switch (reg) { 384 case 0: 385 return (db_regs->tf_r0); 386 case 1: 387 return (db_regs->tf_r1); 388 case 2: 389 return (db_regs->tf_r2); 390 case 3: 391 return (db_regs->tf_r3); 392 case 4: 393 return (db_regs->tf_r4); 394 case 5: 395 return (db_regs->tf_r5); 396 case 6: 397 return (db_regs->tf_r6); 398 case 7: 399 return (db_regs->tf_r7); 400 case 8: 401 return (db_regs->tf_r8); 402 case 9: 403 return (db_regs->tf_r9); 404 case 10: 405 return (db_regs->tf_r10); 406 case 11: 407 return (db_regs->tf_r11); 408 case 12: 409 return (db_regs->tf_r12); 410 case 13: 411 return (db_regs->tf_svc_sp); 412 case 14: 413 return (db_regs->tf_svc_lr); 414 case 15: 415 return (db_regs->tf_pc); 416 default: 417 panic("db_fetch_reg: botch"); 418 } 419 } 420 421 u_int 422 branch_taken(u_int insn, u_int pc, db_regs_t *db_regs) 423 { 424 u_int addr, nregs; 425 426 switch ((insn >> 24) & 0xf) { 427 case 0xa: /* b ... */ 428 case 0xb: /* bl ... */ 429 addr = ((insn << 2) & 0x03ffffff); 430 if (addr & 0x02000000) 431 addr |= 0xfc000000; 432 return (pc + 8 + addr); 433 case 0x7: /* ldr pc, [pc, reg, lsl #2] */ 434 addr = db_fetch_reg(insn & 0xf, db_regs); 435 addr = pc + 8 + (addr << 2); 436 db_read_bytes(addr, 4, (char *)&addr); 437 return (addr); 438 case 0x1: /* mov pc, reg */ 439 addr = db_fetch_reg(insn & 0xf, db_regs); 440 return (addr); 441 case 0x8: /* ldmxx reg, {..., pc} */ 442 case 0x9: 443 addr = db_fetch_reg((insn >> 16) & 0xf, db_regs); 444 nregs = (insn & 0x5555) + ((insn >> 1) & 0x5555); 445 nregs = (nregs & 0x3333) + ((nregs >> 2) & 0x3333); 446 nregs = (nregs + (nregs >> 4)) & 0x0f0f; 447 nregs = (nregs + (nregs >> 8)) & 0x001f; 448 switch ((insn >> 23) & 0x3) { 449 case 0x0: /* ldmda */ 450 addr = addr - 0; 451 break; 452 case 0x1: /* ldmia */ 453 addr = addr + 0 + ((nregs - 1) << 2); 454 break; 455 case 0x2: /* ldmdb */ 456 addr = addr - 4; 457 break; 458 case 0x3: /* ldmib */ 459 addr = addr + 4 + ((nregs - 1) << 2); 460 break; 461 } 462 db_read_bytes(addr, 4, (char *)&addr); 463 return (addr); 464 default: 465 panic("branch_taken: botch"); 466 } 467 } 468
Indexes created Tue Sep 30 11:09:46 GMT 2025