| 1 | |
| 2 | |
| 3 | * 'traps.c' handles hardware traps and faults after we have saved some
|
| 4 | * state in 'entry.S'.
|
| 5 | *
|
| 6 | * SuperH version: Copyright (C) 1999 Niibe Yutaka
|
| 7 | * Copyright (C) 2000 Philipp Rumpf
|
| 8 | * Copyright (C) 2000 David Howells
|
| 9 | * Copyright (C) 2002 - 2010 Paul Mundt
|
| 10 |
|
| 11 | #include <linux/kernel.h>
|
| 12 | #include <linux/ptrace.h>
|
| 13 | #include <linux/hardirq.h>
|
| 14 | #include <linux/init.h>
|
| 15 | #include <linux/spinlock.h>
|
| 16 | #include <linux/kallsyms.h>
|
| 17 | #include <linux/io.h>
|
| 18 | #include <linux/bug.h>
|
| 19 | #include <linux/debug_locks.h>
|
| 20 | #include <linux/kdebug.h>
|
| 21 | #include <linux/limits.h>
|
| 22 | #include <linux/sysfs.h>
|
| 23 | #include <linux/uaccess.h>
|
| 24 | #include <linux/perf_event.h>
|
| 25 | #include <linux/sched/task_stack.h>
|
| 26 |
|
| 27 | #include <asm/alignment.h>
|
| 28 | #include <asm/fpu.h>
|
| 29 | #include <asm/kprobes.h>
|
| 30 | #include <asm/setup.h>
|
| 31 | #include <asm/traps.h>
|
| 32 | #include <asm/bl_bit.h>
|
| 33 |
|
| 34 | #ifdef CONFIG_CPU_SH2
|
| 35 | # define TRAP_RESERVED_INST 4
|
| 36 | # define TRAP_ILLEGAL_SLOT_INST 6
|
| 37 | # define TRAP_ADDRESS_ERROR 9
|
| 38 | # ifdef CONFIG_CPU_SH2A
|
| 39 | # define TRAP_UBC 12
|
| 40 | # define TRAP_FPU_ERROR 13
|
| 41 | # define TRAP_DIVZERO_ERROR 17
|
| 42 | # define TRAP_DIVOVF_ERROR 18
|
| 43 | # endif
|
| 44 | #else
|
| 45 | #define TRAP_RESERVED_INST 12
|
| 46 | #define TRAP_ILLEGAL_SLOT_INST 13
|
| 47 | #endif
|
| 48 |
|
| 49 | static inline void sign_extend(unsigned int count, unsigned char *dst)
|
| 50 | {
|
| 51 | #ifdef __LITTLE_ENDIAN__
|
| 52 | if ((count == 1) && dst[0] & 0x80) {
|
| 53 | dst[1] = 0xff;
|
| 54 | dst[2] = 0xff;
|
| 55 | dst[3] = 0xff;
|
| 56 | }
|
| 57 | if ((count == 2) && dst[1] & 0x80) {
|
| 58 | dst[2] = 0xff;
|
| 59 | dst[3] = 0xff;
|
| 60 | }
|
| 61 | #else
|
| 62 | if ((count == 1) && dst[3] & 0x80) {
|
| 63 | dst[2] = 0xff;
|
| 64 | dst[1] = 0xff;
|
| 65 | dst[0] = 0xff;
|
| 66 | }
|
| 67 | if ((count == 2) && dst[2] & 0x80) {
|
| 68 | dst[1] = 0xff;
|
| 69 | dst[0] = 0xff;
|
| 70 | }
|
| 71 | #endif
|
| 72 | }
|
| 73 |
|
| 74 | static struct mem_access user_mem_access = {
|
| 75 | copy_from_user,
|
| 76 | copy_to_user,
|
| 77 | };
|
| 78 |
|
| 79 | static unsigned long copy_from_kernel_wrapper(void *dst, const void __user *src,
|
| 80 | unsigned long cnt)
|
| 81 | {
|
| 82 | return copy_from_kernel_nofault(dst, (const void __force *)src, cnt);
|
| 83 | }
|
| 84 |
|
| 85 | static unsigned long copy_to_kernel_wrapper(void __user *dst, const void *src,
|
| 86 | unsigned long cnt)
|
| 87 | {
|
| 88 | return copy_to_kernel_nofault((void __force *)dst, src, cnt);
|
| 89 | }
|
| 90 |
|
| 91 | static struct mem_access kernel_mem_access = {
|
| 92 | copy_from_kernel_wrapper,
|
| 93 | copy_to_kernel_wrapper,
|
| 94 | };
|
| 95 |
|
| 96 | |
| 97 | * handle an instruction that does an unaligned memory access by emulating the
|
| 98 | * desired behaviour
|
| 99 | * - note that PC _may not_ point to the faulting instruction
|
| 100 | * (if that instruction is in a branch delay slot)
|
| 101 | * - return 0 if emulation okay, -EFAULT on existential error
|
| 102 |
|
| 103 | static int handle_unaligned_ins(insn_size_t instruction, struct pt_regs *regs,
|
| 104 | struct mem_access *ma)
|
| 105 | {
|
| 106 | int ret, index, count;
|
| 107 | unsigned long *rm, *rn;
|
| 108 | unsigned char *src, *dst;
|
| 109 | unsigned char __user *srcu, *dstu;
|
| 110 |
|
| 111 | index = (instruction>>8)&15;
|
| 112 | rn = ®s->regs[index];
|
| 113 |
|
| 114 | index = (instruction>>4)&15;
|
| 115 | rm = ®s->regs[index];
|
| 116 |
|
| 117 | count = 1<<(instruction&3);
|
| 118 |
|
| 119 | switch (count) {
|
| 120 | case 1: inc_unaligned_byte_access(); break;
|
| 121 | case 2: inc_unaligned_word_access(); break;
|
| 122 | case 4: inc_unaligned_dword_access(); break;
|
| 123 | case 8: inc_unaligned_multi_access(); break;
|
| 124 | }
|
| 125 |
|
| 126 | ret = -EFAULT;
|
| 127 | switch (instruction>>12) {
|
| 128 | case 0:
|
| 129 | if (instruction & 8) {
|
| 130 |
|
| 131 | srcu = (unsigned char __user *)*rm;
|
| 132 | srcu += regs->regs[0];
|
| 133 | dst = (unsigned char *)rn;
|
| 134 | *(unsigned long *)dst = 0;
|
| 135 |
|
| 136 | #if !defined(__LITTLE_ENDIAN__)
|
| 137 | dst += 4-count;
|
| 138 | #endif
|
| 139 | if (ma->from(dst, srcu, count))
|
| 140 | goto fetch_fault;
|
| 141 |
|
| 142 | sign_extend(count, dst);
|
| 143 | } else {
|
| 144 |
|
| 145 | src = (unsigned char *)rm;
|
| 146 | #if !defined(__LITTLE_ENDIAN__)
|
| 147 | src += 4-count;
|
| 148 | #endif
|
| 149 | dstu = (unsigned char __user *)*rn;
|
| 150 | dstu += regs->regs[0];
|
| 151 |
|
| 152 | if (ma->to(dstu, src, count))
|
| 153 | goto fetch_fault;
|
| 154 | }
|
| 155 | ret = 0;
|
| 156 | break;
|
| 157 |
|
| 158 | case 1:
|
| 159 | src = (unsigned char*) rm;
|
| 160 | dstu = (unsigned char __user *)*rn;
|
| 161 | dstu += (instruction&0x000F)<<2;
|
| 162 |
|
| 163 | if (ma->to(dstu, src, 4))
|
| 164 | goto fetch_fault;
|
| 165 | ret = 0;
|
| 166 | break;
|
| 167 |
|
| 168 | case 2:
|
| 169 | if (instruction & 4)
|
| 170 | *rn -= count;
|
| 171 | src = (unsigned char*) rm;
|
| 172 | dstu = (unsigned char __user *)*rn;
|
| 173 | #if !defined(__LITTLE_ENDIAN__)
|
| 174 | src += 4-count;
|
| 175 | #endif
|
| 176 | if (ma->to(dstu, src, count))
|
| 177 | goto fetch_fault;
|
| 178 | ret = 0;
|
| 179 | break;
|
| 180 |
|
| 181 | case 5:
|
| 182 | srcu = (unsigned char __user *)*rm;
|
| 183 | srcu += (instruction & 0x000F) << 2;
|
| 184 | dst = (unsigned char *)rn;
|
| 185 | *(unsigned long *)dst = 0;
|
| 186 |
|
| 187 | if (ma->from(dst, srcu, 4))
|
| 188 | goto fetch_fault;
|
| 189 | ret = 0;
|
| 190 | break;
|
| 191 |
|
| 192 | case 6:
|
| 193 | srcu = (unsigned char __user *)*rm;
|
| 194 | if (instruction & 4)
|
| 195 | *rm += count;
|
| 196 | dst = (unsigned char*) rn;
|
| 197 | *(unsigned long*)dst = 0;
|
| 198 |
|
| 199 | #if !defined(__LITTLE_ENDIAN__)
|
| 200 | dst += 4-count;
|
| 201 | #endif
|
| 202 | if (ma->from(dst, srcu, count))
|
| 203 | goto fetch_fault;
|
| 204 | sign_extend(count, dst);
|
| 205 | ret = 0;
|
| 206 | break;
|
| 207 |
|
| 208 | case 8:
|
| 209 | switch ((instruction&0xFF00)>>8) {
|
| 210 | case 0x81:
|
| 211 | src = (unsigned char *) ®s->regs[0];
|
| 212 | #if !defined(__LITTLE_ENDIAN__)
|
| 213 | src += 2;
|
| 214 | #endif
|
| 215 | dstu = (unsigned char __user *)*rm;
|
| 216 | dstu += (instruction & 0x000F) << 1;
|
| 217 |
|
| 218 | if (ma->to(dstu, src, 2))
|
| 219 | goto fetch_fault;
|
| 220 | ret = 0;
|
| 221 | break;
|
| 222 |
|
| 223 | case 0x85:
|
| 224 | srcu = (unsigned char __user *)*rm;
|
| 225 | srcu += (instruction & 0x000F) << 1;
|
| 226 | dst = (unsigned char *) ®s->regs[0];
|
| 227 | *(unsigned long *)dst = 0;
|
| 228 |
|
| 229 | #if !defined(__LITTLE_ENDIAN__)
|
| 230 | dst += 2;
|
| 231 | #endif
|
| 232 | if (ma->from(dst, srcu, 2))
|
| 233 | goto fetch_fault;
|
| 234 | sign_extend(2, dst);
|
| 235 | ret = 0;
|
| 236 | break;
|
| 237 | }
|
| 238 | break;
|
| 239 |
|
| 240 | case 9:
|
| 241 | srcu = (unsigned char __user *)regs->pc;
|
| 242 | srcu += 4;
|
| 243 | srcu += (instruction & 0x00FF) << 1;
|
| 244 | dst = (unsigned char *)rn;
|
| 245 | *(unsigned long *)dst = 0;
|
| 246 |
|
| 247 | #if !defined(__LITTLE_ENDIAN__)
|
| 248 | dst += 2;
|
| 249 | #endif
|
| 250 |
|
| 251 | if (ma->from(dst, srcu, 2))
|
| 252 | goto fetch_fault;
|
| 253 | sign_extend(2, dst);
|
| 254 | ret = 0;
|
| 255 | break;
|
| 256 |
|
| 257 | case 0xd:
|
| 258 | srcu = (unsigned char __user *)(regs->pc & ~0x3);
|
| 259 | srcu += 4;
|
| 260 | srcu += (instruction & 0x00FF) << 2;
|
| 261 | dst = (unsigned char *)rn;
|
| 262 | *(unsigned long *)dst = 0;
|
| 263 |
|
| 264 | if (ma->from(dst, srcu, 4))
|
| 265 | goto fetch_fault;
|
| 266 | ret = 0;
|
| 267 | break;
|
| 268 | }
|
| 269 | return ret;
|
| 270 |
|
| 271 | fetch_fault:
|
| 272 | |
| 273 | * Raise an EFAULT and see if it's trapped
|
| 274 |
|
| 275 | die_if_no_fixup("Fault in unaligned fixup", regs, 0);
|
| 276 | return -EFAULT;
|
| 277 | }
|
| 278 |
|
| 279 | |
| 280 | * emulate the instruction in the delay slot
|
| 281 | * - fetches the instruction from PC+2
|
| 282 |
|
| 283 | static inline int handle_delayslot(struct pt_regs *regs,
|
| 284 | insn_size_t old_instruction,
|
| 285 | struct mem_access *ma)
|
| 286 | {
|
| 287 | insn_size_t instruction;
|
| 288 | void __user *addr = (void __user *)(regs->pc +
|
| 289 | instruction_size(old_instruction));
|
| 290 |
|
| 291 | if (copy_from_user(&instruction, addr, sizeof(instruction))) {
|
| 292 |
|
| 293 | if (user_mode(regs))
|
| 294 | return -EFAULT;
|
| 295 |
|
| 296 |
|
| 297 | die("delay-slot-insn faulting in handle_unaligned_delayslot",
|
| 298 | regs, 0);
|
| 299 | }
|
| 300 |
|
| 301 | return handle_unaligned_ins(instruction, regs, ma);
|
| 302 | }
|
| 303 |
|
| 304 | |
| 305 | * handle an instruction that does an unaligned memory access
|
| 306 | * - have to be careful of branch delay-slot instructions that fault
|
| 307 | * SH3:
|
| 308 | * - if the branch would be taken PC points to the branch
|
| 309 | * - if the branch would not be taken, PC points to delay-slot
|
| 310 | * SH4:
|
| 311 | * - PC always points to delayed branch
|
| 312 | * - return 0 if handled, -EFAULT if failed (may not return if in kernel)
|
| 313 |
|
| 314 |
|
| 315 |
|
| 316 |
|
| 317 | #define SH_PC_8BIT_OFFSET(instr) ((((signed char)(instr))*2) + 4)
|
| 318 | #define SH_PC_12BIT_OFFSET(instr) ((((signed short)(instr<<4))>>3) + 4)
|
| 319 |
|
| 320 | int handle_unaligned_access(insn_size_t instruction, struct pt_regs *regs,
|
| 321 | struct mem_access *ma, int expected,
|
| 322 | unsigned long address)
|
| 323 | {
|
| 324 | u_int rm;
|
| 325 | int ret, index;
|
| 326 |
|
| 327 | |
| 328 | * XXX: We can't handle mixed 16/32-bit instructions yet
|
| 329 |
|
| 330 | if (instruction_size(instruction) != 2)
|
| 331 | return -EINVAL;
|
| 332 |
|
| 333 | index = (instruction>>8)&15;
|
| 334 | rm = regs->regs[index];
|
| 335 |
|
| 336 | |
| 337 | * Log the unexpected fixups, and then pass them on to perf.
|
| 338 | *
|
| 339 | * We intentionally don't report the expected cases to perf as
|
| 340 | * otherwise the trapped I/O case will skew the results too much
|
| 341 | * to be useful.
|
| 342 |
|
| 343 | if (!expected) {
|
| 344 | unaligned_fixups_notify(current, instruction, regs);
|
| 345 | perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1,
|
| 346 | regs, address);
|
| 347 | }
|
| 348 |
|
| 349 | ret = -EFAULT;
|
| 350 | switch (instruction&0xF000) {
|
| 351 | case 0x0000:
|
| 352 | if (instruction==0x000B) {
|
| 353 |
|
| 354 | ret = handle_delayslot(regs, instruction, ma);
|
| 355 | if (ret==0)
|
| 356 | regs->pc = regs->pr;
|
| 357 | }
|
| 358 | else if ((instruction&0x00FF)==0x0023) {
|
| 359 |
|
| 360 | ret = handle_delayslot(regs, instruction, ma);
|
| 361 | if (ret==0)
|
| 362 | regs->pc += rm + 4;
|
| 363 | }
|
| 364 | else if ((instruction&0x00FF)==0x0003) {
|
| 365 |
|
| 366 | ret = handle_delayslot(regs, instruction, ma);
|
| 367 | if (ret==0) {
|
| 368 | regs->pr = regs->pc + 4;
|
| 369 | regs->pc += rm + 4;
|
| 370 | }
|
| 371 | }
|
| 372 | else {
|
| 373 |
|
| 374 | goto simple;
|
| 375 | }
|
| 376 | break;
|
| 377 |
|
| 378 | case 0x1000:
|
| 379 | goto simple;
|
| 380 |
|
| 381 | case 0x2000:
|
| 382 | goto simple;
|
| 383 |
|
| 384 | case 0x4000:
|
| 385 | if ((instruction&0x00FF)==0x002B) {
|
| 386 |
|
| 387 | ret = handle_delayslot(regs, instruction, ma);
|
| 388 | if (ret==0)
|
| 389 | regs->pc = rm;
|
| 390 | }
|
| 391 | else if ((instruction&0x00FF)==0x000B) {
|
| 392 |
|
| 393 | ret = handle_delayslot(regs, instruction, ma);
|
| 394 | if (ret==0) {
|
| 395 | regs->pr = regs->pc + 4;
|
| 396 | regs->pc = rm;
|
| 397 | }
|
| 398 | }
|
| 399 | else {
|
| 400 |
|
| 401 | goto simple;
|
| 402 | }
|
| 403 | break;
|
| 404 |
|
| 405 | case 0x5000:
|
| 406 | goto simple;
|
| 407 |
|
| 408 | case 0x6000:
|
| 409 | goto simple;
|
| 410 |
|
| 411 | case 0x8000:
|
| 412 | switch (instruction&0x0F00) {
|
| 413 | case 0x0100:
|
| 414 | goto simple;
|
| 415 | case 0x0500:
|
| 416 | goto simple;
|
| 417 | case 0x0B00:
|
| 418 | ret = 0;
|
| 419 | break;
|
| 420 | case 0x0F00:
|
| 421 | ret = handle_delayslot(regs, instruction, ma);
|
| 422 | if (ret==0) {
|
| 423 | #if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
|
| 424 | if ((regs->sr & 0x00000001) != 0)
|
| 425 | regs->pc += 4;
|
| 426 | else
|
| 427 | #endif
|
| 428 | regs->pc += SH_PC_8BIT_OFFSET(instruction);
|
| 429 | }
|
| 430 | break;
|
| 431 | case 0x0900:
|
| 432 | ret = 0;
|
| 433 | break;
|
| 434 | case 0x0D00:
|
| 435 | ret = handle_delayslot(regs, instruction, ma);
|
| 436 | if (ret==0) {
|
| 437 | #if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
|
| 438 | if ((regs->sr & 0x00000001) == 0)
|
| 439 | regs->pc += 4;
|
| 440 | else
|
| 441 | #endif
|
| 442 | regs->pc += SH_PC_8BIT_OFFSET(instruction);
|
| 443 | }
|
| 444 | break;
|
| 445 | }
|
| 446 | break;
|
| 447 |
|
| 448 | case 0x9000:
|
| 449 | goto simple;
|
| 450 |
|
| 451 | case 0xA000:
|
| 452 | ret = handle_delayslot(regs, instruction, ma);
|
| 453 | if (ret==0)
|
| 454 | regs->pc += SH_PC_12BIT_OFFSET(instruction);
|
| 455 | break;
|
| 456 |
|
| 457 | case 0xB000:
|
| 458 | ret = handle_delayslot(regs, instruction, ma);
|
| 459 | if (ret==0) {
|
| 460 | regs->pr = regs->pc + 4;
|
| 461 | regs->pc += SH_PC_12BIT_OFFSET(instruction);
|
| 462 | }
|
| 463 | break;
|
| 464 |
|
| 465 | case 0xD000:
|
| 466 | goto simple;
|
| 467 | }
|
| 468 | return ret;
|
| 469 |
|
| 470 |
|
| 471 | simple:
|
| 472 | ret = handle_unaligned_ins(instruction, regs, ma);
|
| 473 | if (ret==0)
|
| 474 | regs->pc += instruction_size(instruction);
|
| 475 | return ret;
|
| 476 | }
|
| 477 |
|
| 478 | |
| 479 | * Handle various address error exceptions:
|
| 480 | * - instruction address error:
|
| 481 | * misaligned PC
|
| 482 | * PC >= 0x80000000 in user mode
|
| 483 | * - data address error (read and write)
|
| 484 | * misaligned data access
|
| 485 | * access to >= 0x80000000 is user mode
|
| 486 | * Unfortuntaly we can't distinguish between instruction address error
|
| 487 | * and data address errors caused by read accesses.
|
| 488 |
|
| 489 | asmlinkage void do_address_error(struct pt_regs *regs,
|
| 490 | unsigned long writeaccess,
|
| 491 | unsigned long address)
|
| 492 | {
|
| 493 | unsigned long error_code = 0;
|
| 494 | insn_size_t instruction;
|
| 495 | int tmp;
|
| 496 |
|
| 497 |
|
| 498 | #ifdef CONFIG_CPU_HAS_SR_RB
|
| 499 | error_code = lookup_exception_vector();
|
| 500 | #endif
|
| 501 |
|
| 502 | if (user_mode(regs)) {
|
| 503 | int si_code = BUS_ADRERR;
|
| 504 | unsigned int user_action;
|
| 505 |
|
| 506 | local_irq_enable();
|
| 507 | inc_unaligned_user_access();
|
| 508 |
|
| 509 | if (copy_from_user(&instruction, (insn_size_t __user *)(regs->pc & ~1),
|
| 510 | sizeof(instruction))) {
|
| 511 | goto uspace_segv;
|
| 512 | }
|
| 513 |
|
| 514 |
|
| 515 | unaligned_fixups_notify(current, instruction, regs);
|
| 516 |
|
| 517 | user_action = unaligned_user_action();
|
| 518 | if (user_action & UM_FIXUP)
|
| 519 | goto fixup;
|
| 520 | if (user_action & UM_SIGNAL)
|
| 521 | goto uspace_segv;
|
| 522 | else {
|
| 523 |
|
| 524 | regs->pc += instruction_size(instruction);
|
| 525 | return;
|
| 526 | }
|
| 527 |
|
| 528 | fixup:
|
| 529 |
|
| 530 | if (regs->pc & 1) {
|
| 531 | si_code = BUS_ADRALN;
|
| 532 | goto uspace_segv;
|
| 533 | }
|
| 534 |
|
| 535 | tmp = handle_unaligned_access(instruction, regs,
|
| 536 | &user_mem_access, 0,
|
| 537 | address);
|
| 538 |
|
| 539 | if (tmp == 0)
|
| 540 | return;
|
| 541 | uspace_segv:
|
| 542 | printk(KERN_NOTICE "Sending SIGBUS to \"%s\" due to unaligned "
|
| 543 | "access (PC %lx PR %lx)\n", current->comm, regs->pc,
|
| 544 | regs->pr);
|
| 545 |
|
| 546 | force_sig_fault(SIGBUS, si_code, (void __user *)address);
|
| 547 | } else {
|
| 548 | inc_unaligned_kernel_access();
|
| 549 |
|
| 550 | if (regs->pc & 1)
|
| 551 | die("unaligned program counter", regs, error_code);
|
| 552 |
|
| 553 | if (copy_from_kernel_nofault(&instruction, (void *)(regs->pc),
|
| 554 | sizeof(instruction))) {
|
| 555 | |
| 556 | This should never happen non-SMP
|
| 557 |
|
| 558 | die("insn faulting in do_address_error", regs, 0);
|
| 559 | }
|
| 560 |
|
| 561 | unaligned_fixups_notify(current, instruction, regs);
|
| 562 |
|
| 563 | handle_unaligned_access(instruction, regs, &kernel_mem_access,
|
| 564 | 0, address);
|
| 565 | }
|
| 566 | }
|
| 567 |
|
| 568 | #ifdef CONFIG_SH_DSP
|
| 569 | |
| 570 | * SH-DSP support [email protected].
|
| 571 |
|
| 572 | static int is_dsp_inst(struct pt_regs *regs)
|
| 573 | {
|
| 574 | unsigned short inst = 0;
|
| 575 |
|
| 576 | |
| 577 | * Safe guard if DSP mode is already enabled or we're lacking
|
| 578 | * the DSP altogether.
|
| 579 |
|
| 580 | if (!(current_cpu_data.flags & CPU_HAS_DSP) || (regs->sr & SR_DSP))
|
| 581 | return 0;
|
| 582 |
|
| 583 | get_user(inst, ((unsigned short *) regs->pc));
|
| 584 |
|
| 585 | inst &= 0xf000;
|
| 586 |
|
| 587 |
|
| 588 | if ((inst == 0xf000) || (inst == 0x4000))
|
| 589 | return 1;
|
| 590 |
|
| 591 | return 0;
|
| 592 | }
|
| 593 | #else
|
| 594 | static inline int is_dsp_inst(struct pt_regs *regs) { return 0; }
|
| 595 | #endif
|
| 596 |
|
| 597 | #ifdef CONFIG_CPU_SH2A
|
| 598 | asmlinkage void do_divide_error(unsigned long r4)
|
| 599 | {
|
| 600 | int code;
|
| 601 |
|
| 602 | switch (r4) {
|
| 603 | case TRAP_DIVZERO_ERROR:
|
| 604 | code = FPE_INTDIV;
|
| 605 | break;
|
| 606 | case TRAP_DIVOVF_ERROR:
|
| 607 | code = FPE_INTOVF;
|
| 608 | break;
|
| 609 | default:
|
| 610 |
|
| 611 | return;
|
| 612 | }
|
| 613 | force_sig_fault(SIGFPE, code, NULL);
|
| 614 | }
|
| 615 | #endif
|
| 616 |
|
| 617 | asmlinkage void do_reserved_inst(void)
|
| 618 | {
|
| 619 | struct pt_regs *regs = current_pt_regs();
|
| 620 | unsigned long error_code;
|
| 621 |
|
| 622 | #ifdef CONFIG_SH_FPU_EMU
|
| 623 | unsigned short inst = 0;
|
| 624 | int err;
|
| 625 |
|
| 626 | get_user(inst, (unsigned short __user *)regs->pc);
|
| 627 |
|
| 628 | err = do_fpu_inst(inst, regs);
|
| 629 | if (!err) {
|
| 630 | regs->pc += instruction_size(inst);
|
| 631 | return;
|
| 632 | }
|
| 633 |
|
| 634 | #endif
|
| 635 |
|
| 636 | #ifdef CONFIG_SH_DSP
|
| 637 |
|
| 638 | if (is_dsp_inst(regs)) {
|
| 639 |
|
| 640 | regs->sr |= SR_DSP;
|
| 641 |
|
| 642 | current->thread.dsp_status.status |= SR_DSP;
|
| 643 | return;
|
| 644 | }
|
| 645 | #endif
|
| 646 |
|
| 647 | error_code = lookup_exception_vector();
|
| 648 |
|
| 649 | local_irq_enable();
|
| 650 | force_sig(SIGILL);
|
| 651 | die_if_no_fixup("reserved instruction", regs, error_code);
|
| 652 | }
|
| 653 |
|
| 654 | #ifdef CONFIG_SH_FPU_EMU
|
| 655 | static int emulate_branch(unsigned short inst, struct pt_regs *regs)
|
| 656 | {
|
| 657 | |
| 658 | * bfs: 8fxx: PC+=d*2+4;
|
| 659 | * bts: 8dxx: PC+=d*2+4;
|
| 660 | * bra: axxx: PC+=D*2+4;
|
| 661 | * bsr: bxxx: PC+=D*2+4 after PR=PC+4;
|
| 662 | * braf:0x23: PC+=Rn*2+4;
|
| 663 | * bsrf:0x03: PC+=Rn*2+4 after PR=PC+4;
|
| 664 | * jmp: 4x2b: PC=Rn;
|
| 665 | * jsr: 4x0b: PC=Rn after PR=PC+4;
|
| 666 | * rts: 000b: PC=PR;
|
| 667 |
|
| 668 | if (((inst & 0xf000) == 0xb000) ||
|
| 669 | ((inst & 0xf0ff) == 0x0003) ||
|
| 670 | ((inst & 0xf0ff) == 0x400b))
|
| 671 | regs->pr = regs->pc + 4;
|
| 672 |
|
| 673 | if ((inst & 0xfd00) == 0x8d00) {
|
| 674 | regs->pc += SH_PC_8BIT_OFFSET(inst);
|
| 675 | return 0;
|
| 676 | }
|
| 677 |
|
| 678 | if ((inst & 0xe000) == 0xa000) {
|
| 679 | regs->pc += SH_PC_12BIT_OFFSET(inst);
|
| 680 | return 0;
|
| 681 | }
|
| 682 |
|
| 683 | if ((inst & 0xf0df) == 0x0003) {
|
| 684 | regs->pc += regs->regs[(inst & 0x0f00) >> 8] + 4;
|
| 685 | return 0;
|
| 686 | }
|
| 687 |
|
| 688 | if ((inst & 0xf0df) == 0x400b) {
|
| 689 | regs->pc = regs->regs[(inst & 0x0f00) >> 8];
|
| 690 | return 0;
|
| 691 | }
|
| 692 |
|
| 693 | if ((inst & 0xffff) == 0x000b) {
|
| 694 | regs->pc = regs->pr;
|
| 695 | return 0;
|
| 696 | }
|
| 697 |
|
| 698 | return 1;
|
| 699 | }
|
| 700 | #endif
|
| 701 |
|
| 702 | asmlinkage void do_illegal_slot_inst(void)
|
| 703 | {
|
| 704 | struct pt_regs *regs = current_pt_regs();
|
| 705 | unsigned long inst;
|
| 706 |
|
| 707 | if (kprobe_handle_illslot(regs->pc) == 0)
|
| 708 | return;
|
| 709 |
|
| 710 | #ifdef CONFIG_SH_FPU_EMU
|
| 711 | get_user(inst, (unsigned short __user *)regs->pc + 1);
|
| 712 | if (!do_fpu_inst(inst, regs)) {
|
| 713 | get_user(inst, (unsigned short __user *)regs->pc);
|
| 714 | if (!emulate_branch(inst, regs))
|
| 715 | return;
|
| 716 |
|
| 717 | }
|
| 718 |
|
| 719 | #endif
|
| 720 |
|
| 721 | inst = lookup_exception_vector();
|
| 722 |
|
| 723 | local_irq_enable();
|
| 724 | force_sig(SIGILL);
|
| 725 | die_if_no_fixup("illegal slot instruction", regs, inst);
|
| 726 | }
|
| 727 |
|
| 728 | asmlinkage void do_exception_error(void)
|
| 729 | {
|
| 730 | long ex;
|
| 731 |
|
| 732 | ex = lookup_exception_vector();
|
| 733 | die_if_kernel("exception", current_pt_regs(), ex);
|
| 734 | }
|
| 735 |
|
| 736 | void per_cpu_trap_init(void)
|
| 737 | {
|
| 738 | extern void *vbr_base;
|
| 739 |
|
| 740 | |
| 741 | (or P2, virtural "fixed" address space).
|
| 742 | It's definitely should not in physical address.
|
| 743 |
|
| 744 | asm volatile("ldc %0, vbr"
|
| 745 | :
|
| 746 | : "r" (&vbr_base)
|
| 747 | : "memory");
|
| 748 |
|
| 749 |
|
| 750 | clear_bl_bit();
|
| 751 | }
|
| 752 |
|
| 753 | void *set_exception_table_vec(unsigned int vec, void *handler)
|
| 754 | {
|
| 755 | extern void *exception_handling_table[];
|
| 756 | void *old_handler;
|
| 757 |
|
| 758 | old_handler = exception_handling_table[vec];
|
| 759 | exception_handling_table[vec] = handler;
|
| 760 | return old_handler;
|
| 761 | }
|
| 762 |
|
| 763 | void __init trap_init(void)
|
| 764 | {
|
| 765 | set_exception_table_vec(TRAP_RESERVED_INST, do_reserved_inst);
|
| 766 | set_exception_table_vec(TRAP_ILLEGAL_SLOT_INST, do_illegal_slot_inst);
|
| 767 |
|
| 768 | #if defined(CONFIG_CPU_SH4) && !defined(CONFIG_SH_FPU) || \
|
| 769 | defined(CONFIG_SH_FPU_EMU)
|
| 770 | |
| 771 | * For SH-4 lacking an FPU, treat floating point instructions as
|
| 772 | * reserved. They'll be handled in the math-emu case, or faulted on
|
| 773 | * otherwise.
|
| 774 |
|
| 775 | set_exception_table_evt(0x800, do_reserved_inst);
|
| 776 | set_exception_table_evt(0x820, do_illegal_slot_inst);
|
| 777 | #elif defined(CONFIG_SH_FPU)
|
| 778 | set_exception_table_evt(0x800, fpu_state_restore_trap_handler);
|
| 779 | set_exception_table_evt(0x820, fpu_state_restore_trap_handler);
|
| 780 | #endif
|
| 781 |
|
| 782 | #ifdef CONFIG_CPU_SH2
|
| 783 | set_exception_table_vec(TRAP_ADDRESS_ERROR, address_error_trap_handler);
|
| 784 | #endif
|
| 785 | #ifdef CONFIG_CPU_SH2A
|
| 786 | set_exception_table_vec(TRAP_DIVZERO_ERROR, do_divide_error);
|
| 787 | set_exception_table_vec(TRAP_DIVOVF_ERROR, do_divide_error);
|
| 788 | #ifdef CONFIG_SH_FPU
|
| 789 | set_exception_table_vec(TRAP_FPU_ERROR, fpu_error_trap_handler);
|
| 790 | #endif
|
| 791 | #endif
|
| 792 |
|
| 793 | #ifdef TRAP_UBC
|
| 794 | set_exception_table_vec(TRAP_UBC, breakpoint_trap_handler);
|
| 795 | #endif
|
| 796 | }
|