arch/mips/kernel/traps.c

   1 /*
   2  * This file is subject to the terms and conditions of the GNU General Public
   3  * License.  See the file "COPYING" in the main directory of this archive
   4  * for more details.
   5  *
   6  * Copyright (C) 1994 - 1999, 2000, 01, 06 Ralf Baechle
   7  * Copyright (C) 1995, 1996 Paul M. Antoine
   8  * Copyright (C) 1998 Ulf Carlsson
   9  * Copyright (C) 1999 Silicon Graphics, Inc.
  10  * Kevin D. Kissell, [email protected] and Carsten Langgaard, [email protected]
  11  * Copyright (C) 2002, 2003, 2004, 2005, 2007  Maciej W. Rozycki
  12  * Copyright (C) 2000, 2001, 2012 MIPS Technologies, Inc.  All rights reserved.
  13  */
  14 #include <linux/bug.h>
  15 #include <linux/compiler.h>
  16 #include <linux/context_tracking.h>
  17 #include <linux/kexec.h>
  18 #include <linux/init.h>
  19 #include <linux/kernel.h>
  20 #include <linux/module.h>
  21 #include <linux/mm.h>
  22 #include <linux/sched.h>
  23 #include <linux/smp.h>
  24 #include <linux/spinlock.h>
  25 #include <linux/kallsyms.h>
  26 #include <linux/bootmem.h>
  27 #include <linux/interrupt.h>
  28 #include <linux/ptrace.h>
  29 #include <linux/kgdb.h>
  30 #include <linux/kdebug.h>
  31 #include <linux/kprobes.h>
  32 #include <linux/notifier.h>
  33 #include <linux/kdb.h>
  34 #include <linux/irq.h>
  35 #include <linux/perf_event.h>
  36
  37 #include <asm/bootinfo.h>
  38 #include <asm/branch.h>
  39 #include <asm/break.h>
  40 #include <asm/cop2.h>
  41 #include <asm/cpu.h>
  42 #include <asm/dsp.h>
  43 #include <asm/fpu.h>
  44 #include <asm/fpu_emulator.h>
  45 #include <asm/idle.h>
  46 #include <asm/mipsregs.h>
  47 #include <asm/mipsmtregs.h>
  48 #include <asm/module.h>
  49 #include <asm/pgtable.h>
  50 #include <asm/ptrace.h>
  51 #include <asm/sections.h>
  52 #include <asm/tlbdebug.h>
  53 #include <asm/traps.h>
  54 #include <asm/uaccess.h>
  55 #include <asm/watch.h>
  56 #include <asm/mmu_context.h>
  57 #include <asm/types.h>
  58 #include <asm/stacktrace.h>
  59 #include <asm/uasm.h>
  60
  61 extern void check_wait(void);
  62 extern asmlinkage void rollback_handle_int(void);
  63 extern asmlinkage void handle_int(void);
  64 extern u32 handle_tlbl[];
  65 extern u32 handle_tlbs[];
  66 extern u32 handle_tlbm[];
  67 extern asmlinkage void handle_adel(void);
  68 extern asmlinkage void handle_ades(void);
  69 extern asmlinkage void handle_ibe(void);
  70 extern asmlinkage void handle_dbe(void);
  71 extern asmlinkage void handle_sys(void);
  72 extern asmlinkage void handle_bp(void);
  73 extern asmlinkage void handle_ri(void);
  74 extern asmlinkage void handle_ri_rdhwr_vivt(void);
  75 extern asmlinkage void handle_ri_rdhwr(void);
  76 extern asmlinkage void handle_cpu(void);
  77 extern asmlinkage void handle_ov(void);
  78 extern asmlinkage void handle_tr(void);
  79 extern asmlinkage void handle_fpe(void);
  80 extern asmlinkage void handle_mdmx(void);
  81 extern asmlinkage void handle_watch(void);
  82 extern asmlinkage void handle_mt(void);
  83 extern asmlinkage void handle_dsp(void);
  84 extern asmlinkage void handle_mcheck(void);
  85 extern asmlinkage void handle_reserved(void);
  86
  87 void (*board_be_init)(void);
  88 int (*board_be_handler)(struct pt_regs *regs, int is_fixup);
  89 void (*board_nmi_handler_setup)(void);
  90 void (*board_ejtag_handler_setup)(void);
  91 void (*board_bind_eic_interrupt)(int irq, int regset);
  92 void (*board_ebase_setup)(void);
  93 void(*board_cache_error_setup)(void);
  94
  95 static void show_raw_backtrace(unsigned long reg29)
  96 {
  97         unsigned long *sp = (unsigned long *)(reg29 & ~3);
  98         unsigned long addr;
  99
 100         printk("Call Trace:");
 101 #ifdef CONFIG_KALLSYMS
 102         printk("\n");
 103 #endif
 104         while (!kstack_end(sp)) {
 105                 unsigned long __user *p =
 106                         (unsigned long __user *)(unsigned long)sp++;
 107                 if (__get_user(addr, p)) {
 108                         printk(" (Bad stack address)");
 109                         break;
 110                 }
 111                 if (__kernel_text_address(addr))
 112                         print_ip_sym(addr);
 113         }
 114         printk("\n");
 115 }
 116
 117 #ifdef CONFIG_KALLSYMS
 118 int raw_show_trace;
 119 static int __init set_raw_show_trace(char *str)
 120 {
 121         raw_show_trace = 1;
 122         return 1;
 123 }
 124 __setup("raw_show_trace", set_raw_show_trace);
 125 #endif
 126
 127 static void show_backtrace(struct task_struct *task, const struct pt_regs *regs)
 128 {
 129         unsigned long sp = regs->regs[29];
 130         unsigned long ra = regs->regs[31];
 131         unsigned long pc = regs->cp0_epc;
 132
 133         if (!task)
 134                 task = current;
 135
 136         if (raw_show_trace || !__kernel_text_address(pc)) {
 137                 show_raw_backtrace(sp);
 138                 return;
 139         }
 140         printk("Call Trace:\n");
 141         do {
 142                 print_ip_sym(pc);
 143                 pc = unwind_stack(task, &sp, pc, &ra);
 144         } while (pc);
 145         printk("\n");
 146 }
 147
 148 /*
 149  * This routine abuses get_user()/put_user() to reference pointers
 150  * with at least a bit of error checking ...
 151  */
 152 static void show_stacktrace(struct task_struct *task,
 153         const struct pt_regs *regs)
 154 {
 155         const int field = 2 * sizeof(unsigned long);
 156         long stackdata;
 157         int i;
 158         unsigned long __user *sp = (unsigned long __user *)regs->regs[29];
 159
 160         printk("Stack :");
 161         i = 0;
 162         while ((unsigned long) sp & (PAGE_SIZE - 1)) {
 163                 if (i && ((i % (64 / field)) == 0))
 164                         printk("\n       ");
 165                 if (i > 39) {
 166                         printk(" ...");
 167                         break;
 168                 }
 169
 170                 if (__get_user(stackdata, sp++)) {
 171                         printk(" (Bad stack address)");
 172                         break;
 173                 }
 174
 175                 printk(" %0*lx", field, stackdata);
 176                 i++;
 177         }
 178         printk("\n");
 179         show_backtrace(task, regs);
 180 }
 181
 182 void show_stack(struct task_struct *task, unsigned long *sp)
 183 {
 184         struct pt_regs regs;
 185         if (sp) {
 186                 regs.regs[29] = (unsigned long)sp;
 187                 regs.regs[31] = 0;
 188                 regs.cp0_epc = 0;
 189         } else {
 190                 if (task && task != current) {
 191                         regs.regs[29] = task->thread.reg29;
 192                         regs.regs[31] = 0;
 193                         regs.cp0_epc = task->thread.reg31;
 194 #ifdef CONFIG_KGDB_KDB
 195                 } else if (atomic_read(&kgdb_active) != -1 &&
 196                            kdb_current_regs) {
 197                         memcpy(&regs, kdb_current_regs, sizeof(regs));
 198 #endif /* CONFIG_KGDB_KDB */
 199                 } else {
 200                         prepare_frametrace(&regs);
 201                 }
 202         }
 203         show_stacktrace(task, &regs);
 204 }
 205
 206 static void show_code(unsigned int __user *pc)
 207 {
 208         long i;
 209         unsigned short __user *pc16 = NULL;
 210
 211         printk("\nCode:");
 212
 213         if ((unsigned long)pc & 1)
 214                 pc16 = (unsigned short __user *)((unsigned long)pc & ~1);
 215         for(i = -3 ; i < 6 ; i++) {
 216                 unsigned int insn;
 217                 if (pc16 ? __get_user(insn, pc16 + i) : __get_user(insn, pc + i)) {
 218                         printk(" (Bad address in epc)\n");
 219                         break;
 220                 }
 221                 printk("%c%0*x%c", (i?' ':'<'), pc16 ? 4 : 8, insn, (i?' ':'>'));
 222         }
 223 }
 224
 225 static void __show_regs(const struct pt_regs *regs)
 226 {
 227         const int field = 2 * sizeof(unsigned long);
 228         unsigned int cause = regs->cp0_cause;
 229         int i;
 230
 231         show_regs_print_info(KERN_DEFAULT);
 232
 233         /*
 234          * Saved main processor registers
 235          */
 236         for (i = 0; i < 32; ) {
 237                 if ((i % 4) == 0)
 238                         printk("$%2d   :", i);
 239                 if (i == 0)
 240                         printk(" %0*lx", field, 0UL);
 241                 else if (i == 26 || i == 27)
 242                         printk(" %*s", field, "");
 243                 else
 244                         printk(" %0*lx", field, regs->regs[i]);
 245
 246                 i++;
 247                 if ((i % 4) == 0)
 248                         printk("\n");
 249         }
 250
 251 #ifdef CONFIG_CPU_HAS_SMARTMIPS
 252         printk("Acx    : %0*lx\n", field, regs->acx);
 253 #endif
 254         printk("Hi    : %0*lx\n", field, regs->hi);
 255         printk("Lo    : %0*lx\n", field, regs->lo);
 256
 257         /*
 258          * Saved cp0 registers
 259          */
 260         printk("epc   : %0*lx %pS\n", field, regs->cp0_epc,
 261                (void *) regs->cp0_epc);
 262         printk("    %s\n", print_tainted());
 263         printk("ra    : %0*lx %pS\n", field, regs->regs[31],
 264                (void *) regs->regs[31]);
 265
 266         printk("Status: %08x    ", (uint32_t) regs->cp0_status);
 267
 268         if (cpu_has_3kex) {
 269                 if (regs->cp0_status & ST0_KUO)
 270                         printk("KUo ");
 271                 if (regs->cp0_status & ST0_IEO)
 272                         printk("IEo ");
 273                 if (regs->cp0_status & ST0_KUP)
 274                         printk("KUp ");
 275                 if (regs->cp0_status & ST0_IEP)
 276                         printk("IEp ");
 277                 if (regs->cp0_status & ST0_KUC)
 278                         printk("KUc ");
 279                 if (regs->cp0_status & ST0_IEC)
 280                         printk("IEc ");
 281         } else if (cpu_has_4kex) {
 282                 if (regs->cp0_status & ST0_KX)
 283                         printk("KX ");
 284                 if (regs->cp0_status & ST0_SX)
 285                         printk("SX ");
 286                 if (regs->cp0_status & ST0_UX)
 287                         printk("UX ");
 288                 switch (regs->cp0_status & ST0_KSU) {
 289                 case KSU_USER:
 290                         printk("USER ");
 291                         break;
 292                 case KSU_SUPERVISOR:
 293                         printk("SUPERVISOR ");
 294                         break;
 295                 case KSU_KERNEL:
 296                         printk("KERNEL ");
 297                         break;
 298                 default:
 299                         printk("BAD_MODE ");
 300                         break;
 301                 }
 302                 if (regs->cp0_status & ST0_ERL)
 303                         printk("ERL ");
 304                 if (regs->cp0_status & ST0_EXL)
 305                         printk("EXL ");
 306                 if (regs->cp0_status & ST0_IE)
 307                         printk("IE ");
 308         }
 309         printk("\n");
 310
 311         printk("Cause : %08x\n", cause);
 312
 313         cause = (cause & CAUSEF_EXCCODE) >> CAUSEB_EXCCODE;
 314         if (1 <= cause && cause <= 5)
 315                 printk("BadVA : %0*lx\n", field, regs->cp0_badvaddr);
 316
 317         printk("PrId  : %08x (%s)\n", read_c0_prid(),
 318                cpu_name_string());
 319 }
 320
 321 /*
 322  * FIXME: really the generic show_regs should take a const pointer argument.
 323  */
 324 void show_regs(struct pt_regs *regs)
 325 {
 326         __show_regs((struct pt_regs *)regs);
 327 }
 328
 329 void show_registers(struct pt_regs *regs)
 330 {
 331         const int field = 2 * sizeof(unsigned long);
 332
 333         __show_regs(regs);
 334         print_modules();
 335         printk("Process %s (pid: %d, threadinfo=%p, task=%p, tls=%0*lx)\n",
 336                current->comm, current->pid, current_thread_info(), current,
 337               field, current_thread_info()->tp_value);
 338         if (cpu_has_userlocal) {
 339                 unsigned long tls;
 340
 341                 tls = read_c0_userlocal();
 342                 if (tls != current_thread_info()->tp_value)
 343                         printk("*HwTLS: %0*lx\n", field, tls);
 344         }
 345
 346         show_stacktrace(current, regs);
 347         show_code((unsigned int __user *) regs->cp0_epc);
 348         printk("\n");
 349 }
 350
 351 static int regs_to_trapnr(struct pt_regs *regs)
 352 {
 353         return (regs->cp0_cause >> 2) & 0x1f;
 354 }
 355
 356 static DEFINE_RAW_SPINLOCK(die_lock);
 357
 358 void __noreturn die(const char *str, struct pt_regs *regs)
 359 {
 360         static int die_counter;
 361         int sig = SIGSEGV;
 362 #ifdef CONFIG_MIPS_MT_SMTC
 363         unsigned long dvpret;
 364 #endif /* CONFIG_MIPS_MT_SMTC */
 365
 366         oops_enter();
 367
 368         if (notify_die(DIE_OOPS, str, regs, 0, regs_to_trapnr(regs), SIGSEGV) == NOTIFY_STOP)
 369                 sig = 0;
 370
 371         console_verbose();
 372         raw_spin_lock_irq(&die_lock);
 373 #ifdef CONFIG_MIPS_MT_SMTC
 374         dvpret = dvpe();
 375 #endif /* CONFIG_MIPS_MT_SMTC */
 376         bust_spinlocks(1);
 377 #ifdef CONFIG_MIPS_MT_SMTC
 378         mips_mt_regdump(dvpret);
 379 #endif /* CONFIG_MIPS_MT_SMTC */
 380
 381         printk("%s[#%d]:\n", str, ++die_counter);
 382         show_registers(regs);
 383         add_taint(TAINT_DIE, LOCKDEP_NOW_UNRELIABLE);
 384         raw_spin_unlock_irq(&die_lock);
 385
 386         oops_exit();
 387
 388         if (in_interrupt())
 389                 panic("Fatal exception in interrupt");
 390
 391         if (panic_on_oops) {
 392                 printk(KERN_EMERG "Fatal exception: panic in 5 seconds");
 393                 ssleep(5);
 394                 panic("Fatal exception");
 395         }
 396
 397         if (regs && kexec_should_crash(current))
 398                 crash_kexec(regs);
 399
 400         do_exit(sig);
 401 }
 402
 403 extern struct exception_table_entry __start___dbe_table[];
 404 extern struct exception_table_entry __stop___dbe_table[];
 405
 406 __asm__(
 407 "       .section        __dbe_table, \"a\"\n"
 408 "       .previous                       \n");
 409
 410 /* Given an address, look for it in the exception tables. */
 411 static const struct exception_table_entry *search_dbe_tables(unsigned long addr)
 412 {
 413         const struct exception_table_entry *e;
 414
 415         e = search_extable(__start___dbe_table, __stop___dbe_table - 1, addr);
 416         if (!e)
 417                 e = search_module_dbetables(addr);
 418         return e;
 419 }
 420
 421 asmlinkage void do_be(struct pt_regs *regs)
 422 {
 423         const int field = 2 * sizeof(unsigned long);
 424         const struct exception_table_entry *fixup = NULL;
 425         int data = regs->cp0_cause & 4;
 426         int action = MIPS_BE_FATAL;
 427         enum ctx_state prev_state;
 428
 429         prev_state = exception_enter();
 430         /* XXX For now.  Fixme, this searches the wrong table ...  */
 431         if (data && !user_mode(regs))
 432                 fixup = search_dbe_tables(exception_epc(regs));
 433
 434         if (fixup)
 435                 action = MIPS_BE_FIXUP;
 436
 437         if (board_be_handler)
 438                 action = board_be_handler(regs, fixup != NULL);
 439
 440         switch (action) {
 441         case MIPS_BE_DISCARD:
 442                 goto out;
 443         case MIPS_BE_FIXUP:
 444                 if (fixup) {
 445                         regs->cp0_epc = fixup->nextinsn;
 446                         goto out;
 447                 }
 448                 break;
 449         default:
 450                 break;
 451         }
 452
 453         /*
 454          * Assume it would be too dangerous to continue ...
 455          */
 456         printk(KERN_ALERT "%s bus error, epc == %0*lx, ra == %0*lx\n",
 457                data ? "Data" : "Instruction",
 458                field, regs->cp0_epc, field, regs->regs[31]);
 459         if (notify_die(DIE_OOPS, "bus error", regs, 0, regs_to_trapnr(regs), SIGBUS)
 460             == NOTIFY_STOP)
 461                 goto out;
 462
 463         die_if_kernel("Oops", regs);
 464         force_sig(SIGBUS, current);
 465
 466 out:
 467         exception_exit(prev_state);
 468 }
 469
 470 /*
 471  * ll/sc, rdhwr, sync emulation
 472  */
 473
 474 #define OPCODE 0xfc000000
 475 #define BASE   0x03e00000
 476 #define RT     0x001f0000
 477 #define OFFSET 0x0000ffff
 478 #define LL     0xc0000000
 479 #define SC     0xe0000000
 480 #define SPEC0  0x00000000
 481 #define SPEC3  0x7c000000
 482 #define RD     0x0000f800
 483 #define FUNC   0x0000003f
 484 #define SYNC   0x0000000f
 485 #define RDHWR  0x0000003b
 486
 487 /*  microMIPS definitions   */
 488 #define MM_POOL32A_FUNC 0xfc00ffff
 489 #define MM_RDHWR        0x00006b3c
 490 #define MM_RS           0x001f0000
 491 #define MM_RT           0x03e00000
 492
 493 /*
 494  * The ll_bit is cleared by r*_switch.S
 495  */
 496
 497 unsigned int ll_bit;
 498 struct task_struct *ll_task;
 499
 500 static inline int simulate_ll(struct pt_regs *regs, unsigned int opcode)
 501 {
 502         unsigned long value, __user *vaddr;
 503         long offset;
 504
 505         /*
 506          * analyse the ll instruction that just caused a ri exception
 507          * and put the referenced address to addr.
 508          */
 509
 510         /* sign extend offset */
 511         offset = opcode & OFFSET;
 512         offset <<= 16;
 513         offset >>= 16;
 514
 515         vaddr = (unsigned long __user *)
 516                 ((unsigned long)(regs->regs[(opcode & BASE) >> 21]) + offset);
 517
 518         if ((unsigned long)vaddr & 3)
 519                 return SIGBUS;
 520         if (get_user(value, vaddr))
 521                 return SIGSEGV;
 522
 523         preempt_disable();
 524
 525         if (ll_task == NULL || ll_task == current) {
 526                 ll_bit = 1;
 527         } else {
 528                 ll_bit = 0;
 529         }
 530         ll_task = current;
 531
 532         preempt_enable();
 533
 534         regs->regs[(opcode & RT) >> 16] = value;
 535
 536         return 0;
 537 }
 538
 539 static inline int simulate_sc(struct pt_regs *regs, unsigned int opcode)
 540 {
 541         unsigned long __user *vaddr;
 542         unsigned long reg;
 543         long offset;
 544
 545         /*
 546          * analyse the sc instruction that just caused a ri exception
 547          * and put the referenced address to addr.
 548          */
 549
 550         /* sign extend offset */
 551         offset = opcode & OFFSET;
 552         offset <<= 16;
 553         offset >>= 16;
 554
 555         vaddr = (unsigned long __user *)
 556                 ((unsigned long)(regs->regs[(opcode & BASE) >> 21]) + offset);
 557         reg = (opcode & RT) >> 16;
 558
 559         if ((unsigned long)vaddr & 3)
 560                 return SIGBUS;
 561
 562         preempt_disable();
 563
 564         if (ll_bit == 0 || ll_task != current) {
 565                 regs->regs[reg] = 0;
 566                 preempt_enable();
 567                 return 0;
 568         }
 569
 570         preempt_enable();
 571
 572         if (put_user(regs->regs[reg], vaddr))
 573                 return SIGSEGV;
 574
 575         regs->regs[reg] = 1;
 576
 577         return 0;
 578 }
 579
 580 /*
 581  * ll uses the opcode of lwc0 and sc uses the opcode of swc0.  That is both
 582  * opcodes are supposed to result in coprocessor unusable exceptions if
 583  * executed on ll/sc-less processors.  That's the theory.  In practice a
 584  * few processors such as NEC's VR4100 throw reserved instruction exceptions
 585  * instead, so we're doing the emulation thing in both exception handlers.
 586  */
 587 static int simulate_llsc(struct pt_regs *regs, unsigned int opcode)
 588 {
 589         if ((opcode & OPCODE) == LL) {
 590                 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
 591                                 1, regs, 0);
 592                 return simulate_ll(regs, opcode);
 593         }
 594         if ((opcode & OPCODE) == SC) {
 595                 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
 596                                 1, regs, 0);
 597                 return simulate_sc(regs, opcode);
 598         }
 599
 600         return -1;                      /* Must be something else ... */
 601 }
 602
 603 /*
 604  * Simulate trapping 'rdhwr' instructions to provide user accessible
 605  * registers not implemented in hardware.
 606  */
 607 static int simulate_rdhwr(struct pt_regs *regs, int rd, int rt)
 608 {
 609         struct thread_info *ti = task_thread_info(current);
 610
 611         perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
 612                         1, regs, 0);
 613         switch (rd) {
 614         case 0:         /* CPU number */
 615                 regs->regs[rt] = smp_processor_id();
 616                 return 0;
 617         case 1:         /* SYNCI length */
 618                 regs->regs[rt] = min(current_cpu_data.dcache.linesz,
 619                                      current_cpu_data.icache.linesz);
 620                 return 0;
 621         case 2:         /* Read count register */
 622                 regs->regs[rt] = read_c0_count();
 623                 return 0;
 624         case 3:         /* Count register resolution */
 625                 switch (current_cpu_data.cputype) {
 626                 case CPU_20KC:
 627                 case CPU_25KF:
 628                         regs->regs[rt] = 1;
 629                         break;
 630                 default:
 631                         regs->regs[rt] = 2;
 632                 }
 633                 return 0;
 634         case 29:
 635                 regs->regs[rt] = ti->tp_value;
 636                 return 0;
 637         default:
 638                 return -1;
 639         }
 640 }
 641
 642 static int simulate_rdhwr_normal(struct pt_regs *regs, unsigned int opcode)
 643 {
 644         if ((opcode & OPCODE) == SPEC3 && (opcode & FUNC) == RDHWR) {
 645                 int rd = (opcode & RD) >> 11;
 646                 int rt = (opcode & RT) >> 16;
 647
 648                 simulate_rdhwr(regs, rd, rt);
 649                 return 0;
 650         }
 651
 652         /* Not ours.  */
 653         return -1;
 654 }
 655
 656 static int simulate_rdhwr_mm(struct pt_regs *regs, unsigned short opcode)
 657 {
 658         if ((opcode & MM_POOL32A_FUNC) == MM_RDHWR) {
 659                 int rd = (opcode & MM_RS) >> 16;
 660                 int rt = (opcode & MM_RT) >> 21;
 661                 simulate_rdhwr(regs, rd, rt);
 662                 return 0;
 663         }
 664
 665         /* Not ours.  */
 666         return -1;
 667 }
 668
 669 static int simulate_sync(struct pt_regs *regs, unsigned int opcode)
 670 {
 671         if ((opcode & OPCODE) == SPEC0 && (opcode & FUNC) == SYNC) {
 672                 perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS,
 673                                 1, regs, 0);
 674                 return 0;
 675         }
 676
 677         return -1;                      /* Must be something else ... */
 678 }
 679
 680 asmlinkage void do_ov(struct pt_regs *regs)
 681 {
 682         enum ctx_state prev_state;
 683         siginfo_t info;
 684
 685         prev_state = exception_enter();
 686         die_if_kernel("Integer overflow", regs);
 687
 688         info.si_code = FPE_INTOVF;
 689         info.si_signo = SIGFPE;
 690         info.si_errno = 0;
 691         info.si_addr = (void __user *) regs->cp0_epc;
 692         force_sig_info(SIGFPE, &info, current);
 693         exception_exit(prev_state);
 694 }
 695
 696 int process_fpemu_return(int sig, void __user *fault_addr)
 697 {
 698         if (sig == SIGSEGV || sig == SIGBUS) {
 699                 struct siginfo si = {0};
 700                 si.si_addr = fault_addr;
 701                 si.si_signo = sig;
 702                 if (sig == SIGSEGV) {
 703                         if (find_vma(current->mm, (unsigned long)fault_addr))
 704                                 si.si_code = SEGV_ACCERR;
 705                         else
 706                                 si.si_code = SEGV_MAPERR;
 707                 } else {
 708                         si.si_code = BUS_ADRERR;
 709                 }
 710                 force_sig_info(sig, &si, current);
 711                 return 1;
 712         } else if (sig) {
 713                 force_sig(sig, current);
 714                 return 1;
 715         } else {
 716                 return 0;
 717         }
 718 }
 719
 720 /*
 721  * XXX Delayed fp exceptions when doing a lazy ctx switch XXX
 722  */
 723 asmlinkage void do_fpe(struct pt_regs *regs, unsigned long fcr31)
 724 {
 725         enum ctx_state prev_state;
 726         siginfo_t info = {0};
 727
 728         prev_state = exception_enter();
 729         if (notify_die(DIE_FP, "FP exception", regs, 0, regs_to_trapnr(regs), SIGFPE)
 730             == NOTIFY_STOP)
 731                 goto out;
 732         die_if_kernel("FP exception in kernel code", regs);
 733
 734         if (fcr31 & FPU_CSR_UNI_X) {
 735                 int sig;
 736                 void __user *fault_addr = NULL;
 737
 738                 /*
 739                  * Unimplemented operation exception.  If we've got the full
 740                  * software emulator on-board, let's use it...
 741                  *
 742                  * Force FPU to dump state into task/thread context.  We're
 743                  * moving a lot of data here for what is probably a single
 744                  * instruction, but the alternative is to pre-decode the FP
 745                  * register operands before invoking the emulator, which seems
 746                  * a bit extreme for what should be an infrequent event.
 747                  */
 748                 /* Ensure 'resume' not overwrite saved fp context again. */
 749                 lose_fpu(1);
 750
 751                 /* Run the emulator */
 752                 sig = fpu_emulator_cop1Handler(regs, &current->thread.fpu, 1,
 753                                                &fault_addr);
 754
 755                 /*
 756                  * We can't allow the emulated instruction to leave any of
 757                  * the cause bit set in $fcr31.
 758                  */
 759                 current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X;
 760
 761                 /* Restore the hardware register state */
 762                 own_fpu(1);     /* Using the FPU again.  */
 763
 764                 /* If something went wrong, signal */
 765                 process_fpemu_return(sig, fault_addr);
 766
 767                 goto out;
 768         } else if (fcr31 & FPU_CSR_INV_X)
 769                 info.si_code = FPE_FLTINV;
 770         else if (fcr31 & FPU_CSR_DIV_X)
 771                 info.si_code = FPE_FLTDIV;
 772         else if (fcr31 & FPU_CSR_OVF_X)
 773                 info.si_code = FPE_FLTOVF;
 774         else if (fcr31 & FPU_CSR_UDF_X)
 775                 info.si_code = FPE_FLTUND;
 776         else if (fcr31 & FPU_CSR_INE_X)
 777                 info.si_code = FPE_FLTRES;
 778         else
 779                 info.si_code = __SI_FAULT;
 780         info.si_signo = SIGFPE;
 781         info.si_errno = 0;
 782         info.si_addr = (void __user *) regs->cp0_epc;
 783         force_sig_info(SIGFPE, &info, current);
 784
 785 out:
 786         exception_exit(prev_state);
 787 }
 788
 789 static void do_trap_or_bp(struct pt_regs *regs, unsigned int code,
 790         const char *str)
 791 {
 792         siginfo_t info;
 793         char b[40];
 794
 795 #ifdef CONFIG_KGDB_LOW_LEVEL_TRAP
 796         if (kgdb_ll_trap(DIE_TRAP, str, regs, code, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP)
 797                 return;
 798 #endif /* CONFIG_KGDB_LOW_LEVEL_TRAP */
 799
 800         if (notify_die(DIE_TRAP, str, regs, code, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP)
 801                 return;
 802
 803         /*
 804          * A short test says that IRIX 5.3 sends SIGTRAP for all trap
 805          * insns, even for trap and break codes that indicate arithmetic
 806          * failures.  Weird ...
 807          * But should we continue the brokenness???  --macro
 808          */
 809         switch (code) {
 810         case BRK_OVERFLOW:
 811         case BRK_DIVZERO:
 812                 scnprintf(b, sizeof(b), "%s instruction in kernel code", str);
 813                 die_if_kernel(b, regs);
 814                 if (code == BRK_DIVZERO)
 815                         info.si_code = FPE_INTDIV;
 816                 else
 817                         info.si_code = FPE_INTOVF;
 818                 info.si_signo = SIGFPE;
 819                 info.si_errno = 0;
 820                 info.si_addr = (void __user *) regs->cp0_epc;
 821                 force_sig_info(SIGFPE, &info, current);
 822                 break;
 823         case BRK_BUG:
 824                 die_if_kernel("Kernel bug detected", regs);
 825                 force_sig(SIGTRAP, current);
 826                 break;
 827         case BRK_MEMU:
 828                 /*
 829                  * Address errors may be deliberately induced by the FPU
 830                  * emulator to retake control of the CPU after executing the
 831                  * instruction in the delay slot of an emulated branch.
 832                  *
 833                  * Terminate if exception was recognized as a delay slot return
 834                  * otherwise handle as normal.
 835                  */
 836                 if (do_dsemulret(regs))
 837                         return;
 838
 839                 die_if_kernel("Math emu break/trap", regs);
 840                 force_sig(SIGTRAP, current);
 841                 break;
 842         default:
 843                 scnprintf(b, sizeof(b), "%s instruction in kernel code", str);
 844                 die_if_kernel(b, regs);
 845                 force_sig(SIGTRAP, current);
 846         }
 847 }
 848
 849 asmlinkage void do_bp(struct pt_regs *regs)
 850 {
 851         unsigned int opcode, bcode;
 852         enum ctx_state prev_state;
 853         unsigned long epc;
 854         u16 instr[2];
 855
 856         prev_state = exception_enter();
 857         if (get_isa16_mode(regs->cp0_epc)) {
 858                 /* Calculate EPC. */
 859                 epc = exception_epc(regs);
 860                 if (cpu_has_mmips) {
 861                         if ((__get_user(instr[0], (u16 __user *)msk_isa16_mode(epc)) ||
 862                             (__get_user(instr[1], (u16 __user *)msk_isa16_mode(epc + 2)))))
 863                                 goto out_sigsegv;
 864                     opcode = (instr[0] << 16) | instr[1];
 865                 } else {
 866                     /* MIPS16e mode */
 867                     if (__get_user(instr[0], (u16 __user *)msk_isa16_mode(epc)))
 868                                 goto out_sigsegv;
 869                     bcode = (instr[0] >> 6) & 0x3f;
 870                     do_trap_or_bp(regs, bcode, "Break");
 871                     goto out;
 872                 }
 873         } else {
 874                 if (__get_user(opcode, (unsigned int __user *) exception_epc(regs)))
 875                         goto out_sigsegv;
 876         }
 877
 878         /*
 879          * There is the ancient bug in the MIPS assemblers that the break
 880          * code starts left to bit 16 instead to bit 6 in the opcode.
 881          * Gas is bug-compatible, but not always, grrr...
 882          * We handle both cases with a simple heuristics.  --macro
 883          */
 884         bcode = ((opcode >> 6) & ((1 << 20) - 1));
 885         if (bcode >= (1 << 10))
 886                 bcode >>= 10;
 887
 888         /*
 889          * notify the kprobe handlers, if instruction is likely to
 890          * pertain to them.
 891          */
 892         switch (bcode) {
 893         case BRK_KPROBE_BP:
 894                 if (notify_die(DIE_BREAK, "debug", regs, bcode, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP)
 895                         goto out;
 896                 else
 897                         break;
 898         case BRK_KPROBE_SSTEPBP:
 899                 if (notify_die(DIE_SSTEPBP, "single_step", regs, bcode, regs_to_trapnr(regs), SIGTRAP) == NOTIFY_STOP)
 900                         goto out;
 901                 else
 902                         break;
 903         default:
 904                 break;
 905         }
 906
 907         do_trap_or_bp(regs, bcode, "Break");
 908
 909 out:
 910         exception_exit(prev_state);
 911         return;
 912
 913 out_sigsegv:
 914         force_sig(SIGSEGV, current);
 915         goto out;
 916 }
 917
 918 asmlinkage void do_tr(struct pt_regs *regs)
 919 {
 920         u32 opcode, tcode = 0;
 921         enum ctx_state prev_state;
 922         u16 instr[2];
 923         unsigned long epc = msk_isa16_mode(exception_epc(regs));
 924
 925         prev_state = exception_enter();
 926         if (get_isa16_mode(regs->cp0_epc)) {
 927                 if (__get_user(instr[0], (u16 __user *)(epc + 0)) ||
 928                     __get_user(instr[1], (u16 __user *)(epc + 2)))
 929                         goto out_sigsegv;
 930                 opcode = (instr[0] << 16) | instr[1];
 931                 /* Immediate versions don't provide a code.  */
 932                 if (!(opcode & OPCODE))
 933                         tcode = (opcode >> 12) & ((1 << 4) - 1);
 934         } else {
 935                 if (__get_user(opcode, (u32 __user *)epc))
 936                         goto out_sigsegv;
 937                 /* Immediate versions don't provide a code.  */
 938                 if (!(opcode & OPCODE))
 939                         tcode = (opcode >> 6) & ((1 << 10) - 1);
 940         }
 941
 942         do_trap_or_bp(regs, tcode, "Trap");
 943
 944 out:
 945         exception_exit(prev_state);
 946         return;
 947
 948 out_sigsegv:
 949         force_sig(SIGSEGV, current);
 950         goto out;
 951 }
 952
 953 asmlinkage void do_ri(struct pt_regs *regs)
 954 {
 955         unsigned int __user *epc = (unsigned int __user *)exception_epc(regs);
 956         unsigned long old_epc = regs->cp0_epc;
 957         unsigned long old31 = regs->regs[31];
 958         enum ctx_state prev_state;
 959         unsigned int opcode = 0;
 960         int status = -1;
 961
 962         prev_state = exception_enter();
 963         if (notify_die(DIE_RI, "RI Fault", regs, 0, regs_to_trapnr(regs), SIGILL)
 964             == NOTIFY_STOP)
 965                 goto out;
 966
 967         die_if_kernel("Reserved instruction in kernel code", regs);
 968
 969         if (unlikely(compute_return_epc(regs) < 0))
 970                 goto out;
 971
 972         if (get_isa16_mode(regs->cp0_epc)) {
 973                 unsigned short mmop[2] = { 0 };
 974
 975                 if (unlikely(get_user(mmop[0], epc) < 0))
 976                         status = SIGSEGV;
 977                 if (unlikely(get_user(mmop[1], epc) < 0))
 978                         status = SIGSEGV;
 979                 opcode = (mmop[0] << 16) | mmop[1];
 980
 981                 if (status < 0)
 982                         status = simulate_rdhwr_mm(regs, opcode);
 983         } else {
 984                 if (unlikely(get_user(opcode, epc) < 0))
 985                         status = SIGSEGV;
 986
 987                 if (!cpu_has_llsc && status < 0)
 988                         status = simulate_llsc(regs, opcode);
 989
 990                 if (status < 0)
 991                         status = simulate_rdhwr_normal(regs, opcode);
 992
 993                 if (status < 0)
 994                         status = simulate_sync(regs, opcode);
 995         }
 996
 997         if (status < 0)
 998                 status = SIGILL;
 999
1000         if (unlikely(status > 0)) {
1001                 regs->cp0_epc = old_epc;                /* Undo skip-over.  */
1002                 regs->regs[31] = old31;
1003                 force_sig(status, current);
1004         }
1005
1006 out:
1007         exception_exit(prev_state);
1008 }
1009
1010 /*
1011  * MIPS MT processors may have fewer FPU contexts than CPU threads. If we've
1012  * emulated more than some threshold number of instructions, force migration to
1013  * a "CPU" that has FP support.
1014  */
1015 static void mt_ase_fp_affinity(void)
1016 {
1017 #ifdef CONFIG_MIPS_MT_FPAFF
1018         if (mt_fpemul_threshold > 0 &&
1019              ((current->thread.emulated_fp++ > mt_fpemul_threshold))) {
1020                 /*
1021                  * If there's no FPU present, or if the application has already
1022                  * restricted the allowed set to exclude any CPUs with FPUs,
1023                  * we'll skip the procedure.
1024                  */
1025                 if (cpus_intersects(current->cpus_allowed, mt_fpu_cpumask)) {
1026                         cpumask_t tmask;
1027
1028                         current->thread.user_cpus_allowed
1029                                 = current->cpus_allowed;
1030                         cpus_and(tmask, current->cpus_allowed,
1031                                 mt_fpu_cpumask);
1032                         set_cpus_allowed_ptr(current, &tmask);
1033                         set_thread_flag(TIF_FPUBOUND);
1034                 }
1035         }
1036 #endif /* CONFIG_MIPS_MT_FPAFF */
1037 }
1038
1039 /*
1040  * No lock; only written during early bootup by CPU 0.
1041  */
1042 static RAW_NOTIFIER_HEAD(cu2_chain);
1043
1044 int __ref register_cu2_notifier(struct notifier_block *nb)
1045 {
1046         return raw_notifier_chain_register(&cu2_chain, nb);
1047 }
1048
1049 int cu2_notifier_call_chain(unsigned long val, void *v)
1050 {
1051         return raw_notifier_call_chain(&cu2_chain, val, v);
1052 }
1053
1054 static int default_cu2_call(struct notifier_block *nfb, unsigned long action,
1055         void *data)
1056 {
1057         struct pt_regs *regs = data;
1058
1059         die_if_kernel("COP2: Unhandled kernel unaligned access or invalid "
1060                               "instruction", regs);
1061         force_sig(SIGILL, current);
1062
1063         return NOTIFY_OK;
1064 }
1065
1066 asmlinkage void do_cpu(struct pt_regs *regs)
1067 {
1068         enum ctx_state prev_state;
1069         unsigned int __user *epc;
1070         unsigned long old_epc, old31;
1071         unsigned int opcode;
1072         unsigned int cpid;
1073         int status;
1074         unsigned long __maybe_unused flags;
1075
1076         prev_state = exception_enter();
1077         cpid = (regs->cp0_cause >> CAUSEB_CE) & 3;
1078
1079         if (cpid != 2)
1080                 die_if_kernel("do_cpu invoked from kernel context!", regs);
1081
1082         switch (cpid) {
1083         case 0:
1084                 epc = (unsigned int __user *)exception_epc(regs);
1085                 old_epc = regs->cp0_epc;
1086                 old31 = regs->regs[31];
1087                 opcode = 0;
1088                 status = -1;
1089
1090                 if (unlikely(compute_return_epc(regs) < 0))
1091                         goto out;
1092
1093                 if (get_isa16_mode(regs->cp0_epc)) {
1094                         unsigned short mmop[2] = { 0 };
1095
1096                         if (unlikely(get_user(mmop[0], epc) < 0))
1097                                 status = SIGSEGV;
1098                         if (unlikely(get_user(mmop[1], epc) < 0))
1099                                 status = SIGSEGV;
1100                         opcode = (mmop[0] << 16) | mmop[1];
1101
1102                         if (status < 0)
1103                                 status = simulate_rdhwr_mm(regs, opcode);
1104                 } else {
1105                         if (unlikely(get_user(opcode, epc) < 0))
1106                                 status = SIGSEGV;
1107
1108                         if (!cpu_has_llsc && status < 0)
1109                                 status = simulate_llsc(regs, opcode);
1110
1111                         if (status < 0)
1112                                 status = simulate_rdhwr_normal(regs, opcode);
1113                 }
1114
1115                 if (status < 0)
1116                         status = SIGILL;
1117
1118                 if (unlikely(status > 0)) {
1119                         regs->cp0_epc = old_epc;        /* Undo skip-over.  */
1120                         regs->regs[31] = old31;
1121                         force_sig(status, current);
1122                 }
1123
1124                 goto out;
1125
1126         case 3:
1127                 /*
1128                  * Old (MIPS I and MIPS II) processors will set this code
1129                  * for COP1X opcode instructions that replaced the original
1130                  * COP3 space.  We don't limit COP1 space instructions in
1131                  * the emulator according to the CPU ISA, so we want to
1132                  * treat COP1X instructions consistently regardless of which
1133                  * code the CPU chose.  Therefore we redirect this trap to
1134                  * the FP emulator too.
1135                  *
1136                  * Then some newer FPU-less processors use this code
1137                  * erroneously too, so they are covered by this choice
1138                  * as well.
1139                  */
1140                 if (raw_cpu_has_fpu)
1141                         break;
1142                 /* Fall through.  */
1143
1144         case 1:
1145                 if (used_math())        /* Using the FPU again.  */
1146                         own_fpu(1);
1147                 else {                  /* First time FPU user.  */
1148                         init_fpu();
1149                         set_used_math();
1150                 }
1151
1152                 if (!raw_cpu_has_fpu) {
1153                         int sig;
1154                         void __user *fault_addr = NULL;
1155                         sig = fpu_emulator_cop1Handler(regs,
1156                                                        &current->thread.fpu,
1157                                                        0, &fault_addr);
1158                         if (!process_fpemu_return(sig, fault_addr))
1159                                 mt_ase_fp_affinity();
1160                 }
1161
1162                 goto out;
1163
1164         case 2:
1165                 raw_notifier_call_chain(&cu2_chain, CU2_EXCEPTION, regs);
1166                 goto out;
1167         }
1168
1169         force_sig(SIGILL, current);
1170
1171 out:
1172         exception_exit(prev_state);
1173 }
1174
1175 asmlinkage void do_mdmx(struct pt_regs *regs)
1176 {
1177         enum ctx_state prev_state;
1178
1179         prev_state = exception_enter();
1180         force_sig(SIGILL, current);
1181         exception_exit(prev_state);
1182 }
1183
1184 /*
1185  * Called with interrupts disabled.
1186  */
1187 asmlinkage void do_watch(struct pt_regs *regs)
1188 {
1189         enum ctx_state prev_state;
1190         u32 cause;
1191
1192         prev_state = exception_enter();
1193         /*
1194          * Clear WP (bit 22) bit of cause register so we don't loop
1195          * forever.
1196          */
1197         cause = read_c0_cause();
1198         cause &= ~(1 << 22);
1199         write_c0_cause(cause);
1200
1201         /*
1202          * If the current thread has the watch registers loaded, save
1203          * their values and send SIGTRAP.  Otherwise another thread
1204          * left the registers set, clear them and continue.
1205          */
1206         if (test_tsk_thread_flag(current, TIF_LOAD_WATCH)) {
1207                 mips_read_watch_registers();
1208                 local_irq_enable();
1209                 force_sig(SIGTRAP, current);
1210         } else {
1211                 mips_clear_watch_registers();
1212                 local_irq_enable();
1213         }
1214         exception_exit(prev_state);
1215 }
1216
1217 asmlinkage void do_mcheck(struct pt_regs *regs)
1218 {
1219         const int field = 2 * sizeof(unsigned long);
1220         int multi_match = regs->cp0_status & ST0_TS;
1221         enum ctx_state prev_state;
1222
1223         prev_state = exception_enter();
1224         show_regs(regs);
1225
1226         if (multi_match) {
1227                 printk("Index   : %0x\n", read_c0_index());
1228                 printk("Pagemask: %0x\n", read_c0_pagemask());
1229                 printk("EntryHi : %0*lx\n", field, read_c0_entryhi());
1230                 printk("EntryLo0: %0*lx\n", field, read_c0_entrylo0());
1231                 printk("EntryLo1: %0*lx\n", field, read_c0_entrylo1());
1232                 printk("\n");
1233                 dump_tlb_all();
1234         }
1235
1236         show_code((unsigned int __user *) regs->cp0_epc);
1237
1238         /*
1239          * Some chips may have other causes of machine check (e.g. SB1
1240          * graduation timer)
1241          */
1242         panic("Caught Machine Check exception - %scaused by multiple "
1243               "matching entries in the TLB.",
1244               (multi_match) ? "" : "not ");
1245 }
1246
1247 asmlinkage void do_mt(struct pt_regs *regs)
1248 {
1249         int subcode;
1250
1251         subcode = (read_vpe_c0_vpecontrol() & VPECONTROL_EXCPT)
1252                         >> VPECONTROL_EXCPT_SHIFT;
1253         switch (subcode) {
1254         case 0:
1255                 printk(KERN_DEBUG "Thread Underflow\n");
1256                 break;
1257         case 1:
1258                 printk(KERN_DEBUG "Thread Overflow\n");
1259                 break;
1260         case 2:
1261                 printk(KERN_DEBUG "Invalid YIELD Qualifier\n");
1262                 break;
1263         case 3:
1264                 printk(KERN_DEBUG "Gating Storage Exception\n");
1265                 break;
1266         case 4:
1267                 printk(KERN_DEBUG "YIELD Scheduler Exception\n");
1268                 break;
1269         case 5:
1270                 printk(KERN_DEBUG "Gating Storage Scheduler Exception\n");
1271                 break;
1272         default:
1273                 printk(KERN_DEBUG "*** UNKNOWN THREAD EXCEPTION %d ***\n",
1274                         subcode);
1275                 break;
1276         }
1277         die_if_kernel("MIPS MT Thread exception in kernel", regs);
1278
1279         force_sig(SIGILL, current);
1280 }
1281
1282
1283 asmlinkage void do_dsp(struct pt_regs *regs)
1284 {
1285         if (cpu_has_dsp)
1286                 panic("Unexpected DSP exception");
1287
1288         force_sig(SIGILL, current);
1289 }
1290
1291 asmlinkage void do_reserved(struct pt_regs *regs)
1292 {
1293         /*
1294          * Game over - no way to handle this if it ever occurs.  Most probably
1295          * caused by a new unknown cpu type or after another deadly
1296          * hard/software error.
1297          */
1298         show_regs(regs);
1299         panic("Caught reserved exception %ld - should not happen.",
1300               (regs->cp0_cause & 0x7f) >> 2);
1301 }
1302
1303 static int __initdata l1parity = 1;
1304 static int __init nol1parity(char *s)
1305 {
1306         l1parity = 0;
1307         return 1;
1308 }
1309 __setup("nol1par", nol1parity);
1310 static int __initdata l2parity = 1;
1311 static int __init nol2parity(char *s)
1312 {
1313         l2parity = 0;
1314         return 1;
1315 }
1316 __setup("nol2par", nol2parity);
1317
1318 /*
1319  * Some MIPS CPUs can enable/disable for cache parity detection, but do
1320  * it different ways.
1321  */
1322 static inline void parity_protection_init(void)
1323 {
1324         switch (current_cpu_type()) {
1325         case CPU_24K:
1326         case CPU_34K:
1327         case CPU_74K:
1328         case CPU_1004K:
1329                 {
1330 #define ERRCTL_PE       0x80000000
1331 #define ERRCTL_L2P      0x00800000
1332                         unsigned long errctl;
1333                         unsigned int l1parity_present, l2parity_present;
1334
1335                         errctl = read_c0_ecc();
1336                         errctl &= ~(ERRCTL_PE|ERRCTL_L2P);
1337
1338                         /* probe L1 parity support */
1339                         write_c0_ecc(errctl | ERRCTL_PE);
1340                         back_to_back_c0_hazard();
1341                         l1parity_present = (read_c0_ecc() & ERRCTL_PE);
1342
1343                         /* probe L2 parity support */
1344                         write_c0_ecc(errctl|ERRCTL_L2P);
1345                         back_to_back_c0_hazard();
1346                         l2parity_present = (read_c0_ecc() & ERRCTL_L2P);
1347
1348                         if (l1parity_present && l2parity_present) {
1349                                 if (l1parity)
1350                                         errctl |= ERRCTL_PE;
1351                                 if (l1parity ^ l2parity)
1352                                         errctl |= ERRCTL_L2P;
1353                         } else if (l1parity_present) {
1354                                 if (l1parity)
1355                                         errctl |= ERRCTL_PE;
1356                         } else if (l2parity_present) {
1357                                 if (l2parity)
1358                                         errctl |= ERRCTL_L2P;
1359                         } else {
1360                                 /* No parity available */
1361                         }
1362
1363                         printk(KERN_INFO "Writing ErrCtl register=%08lx\n", errctl);
1364
1365                         write_c0_ecc(errctl);
1366                         back_to_back_c0_hazard();
1367                         errctl = read_c0_ecc();
1368                         printk(KERN_INFO "Readback ErrCtl register=%08lx\n", errctl);
1369
1370                         if (l1parity_present)
1371                                 printk(KERN_INFO "Cache parity protection %sabled\n",
1372                                        (errctl & ERRCTL_PE) ? "en" : "dis");
1373
1374                         if (l2parity_present) {
1375                                 if (l1parity_present && l1parity)
1376                                         errctl ^= ERRCTL_L2P;
1377                                 printk(KERN_INFO "L2 cache parity protection %sabled\n",
1378                                        (errctl & ERRCTL_L2P) ? "en" : "dis");
1379                         }
1380                 }
1381                 break;
1382
1383         case CPU_5KC:
1384         case CPU_5KE:
1385         case CPU_LOONGSON1:
1386                 write_c0_ecc(0x80000000);
1387                 back_to_back_c0_hazard();
1388                 /* Set the PE bit (bit 31) in the c0_errctl register. */
1389                 printk(KERN_INFO "Cache parity protection %sabled\n",
1390                        (read_c0_ecc() & 0x80000000) ? "en" : "dis");
1391                 break;
1392         case CPU_20KC:
1393         case CPU_25KF:
1394                 /* Clear the DE bit (bit 16) in the c0_status register. */
1395                 printk(KERN_INFO "Enable cache parity protection for "
1396                        "MIPS 20KC/25KF CPUs.\n");
1397                 clear_c0_status(ST0_DE);
1398                 break;
1399         default:
1400                 break;
1401         }
1402 }
1403
1404 asmlinkage void cache_parity_error(void)
1405 {
1406         const int field = 2 * sizeof(unsigned long);
1407         unsigned int reg_val;
1408
1409         /* For the moment, report the problem and hang. */
1410         printk("Cache error exception:\n");
1411         printk("cp0_errorepc == %0*lx\n", field, read_c0_errorepc());
1412         reg_val = read_c0_cacheerr();
1413         printk("c0_cacheerr == %08x\n", reg_val);
1414
1415         printk("Decoded c0_cacheerr: %s cache fault in %s reference.\n",
1416                reg_val & (1<<30) ? "secondary" : "primary",
1417                reg_val & (1<<31) ? "data" : "insn");
1418         printk("Error bits: %s%s%s%s%s%s%s\n",
1419                reg_val & (1<<29) ? "ED " : "",
1420                reg_val & (1<<28) ? "ET " : "",
1421                reg_val & (1<<26) ? "EE " : "",
1422                reg_val & (1<<25) ? "EB " : "",
1423                reg_val & (1<<24) ? "EI " : "",
1424                reg_val & (1<<23) ? "E1 " : "",
1425                reg_val & (1<<22) ? "E0 " : "");
1426         printk("IDX: 0x%08x\n", reg_val & ((1<<22)-1));
1427
1428 #if defined(CONFIG_CPU_MIPS32) || defined(CONFIG_CPU_MIPS64)
1429         if (reg_val & (1<<22))
1430                 printk("DErrAddr0: 0x%0*lx\n", field, read_c0_derraddr0());
1431
1432         if (reg_val & (1<<23))
1433                 printk("DErrAddr1: 0x%0*lx\n", field, read_c0_derraddr1());
1434 #endif
1435
1436         panic("Can't handle the cache error!");
1437 }
1438
1439 /*
1440  * SDBBP EJTAG debug exception handler.
1441  * We skip the instruction and return to the next instruction.
1442  */
1443 void ejtag_exception_handler(struct pt_regs *regs)
1444 {
1445         const int field = 2 * sizeof(unsigned long);
1446         unsigned long depc, old_epc, old_ra;
1447         unsigned int debug;
1448
1449         printk(KERN_DEBUG "SDBBP EJTAG debug exception - not handled yet, just ignored!\n");
1450         depc = read_c0_depc();
1451         debug = read_c0_debug();
1452         printk(KERN_DEBUG "c0_depc = %0*lx, DEBUG = %08x\n", field, depc, debug);
1453         if (debug & 0x80000000) {
1454                 /*
1455                  * In branch delay slot.
1456                  * We cheat a little bit here and use EPC to calculate the
1457                  * debug return address (DEPC). EPC is restored after the
1458                  * calculation.
1459                  */
1460                 old_epc = regs->cp0_epc;
1461                 old_ra = regs->regs[31];
1462                 regs->cp0_epc = depc;
1463                 compute_return_epc(regs);
1464                 depc = regs->cp0_epc;
1465                 regs->cp0_epc = old_epc;
1466                 regs->regs[31] = old_ra;
1467         } else
1468                 depc += 4;
1469         write_c0_depc(depc);
1470
1471 #if 0
1472         printk(KERN_DEBUG "\n\n----- Enable EJTAG single stepping ----\n\n");
1473         write_c0_debug(debug | 0x100);
1474 #endif
1475 }
1476
1477 /*
1478  * NMI exception handler.
1479  * No lock; only written during early bootup by CPU 0.
1480  */
1481 static RAW_NOTIFIER_HEAD(nmi_chain);
1482
1483 int register_nmi_notifier(struct notifier_block *nb)
1484 {
1485         return raw_notifier_chain_register(&nmi_chain, nb);
1486 }
1487
1488 void __noreturn nmi_exception_handler(struct pt_regs *regs)
1489 {
1490         raw_notifier_call_chain(&nmi_chain, 0, regs);
1491         bust_spinlocks(1);
1492         printk("NMI taken!!!!\n");
1493         die("NMI", regs);
1494 }
1495
1496 #define VECTORSPACING 0x100     /* for EI/VI mode */
1497
1498 unsigned long ebase;
1499 unsigned long exception_handlers[32];
1500 unsigned long vi_handlers[64];
1501
1502 void __init *set_except_vector(int n, void *addr)
1503 {
1504         unsigned long handler = (unsigned long) addr;
1505         unsigned long old_handler;
1506
1507 #ifdef CONFIG_CPU_MICROMIPS
1508         /*
1509          * Only the TLB handlers are cache aligned with an even
1510          * address. All other handlers are on an odd address and
1511          * require no modification. Otherwise, MIPS32 mode will
1512          * be entered when handling any TLB exceptions. That
1513          * would be bad...since we must stay in microMIPS mode.
1514          */
1515         if (!(handler & 0x1))
1516                 handler |= 1;
1517 #endif
1518         old_handler = xchg(&exception_handlers[n], handler);
1519
1520         if (n == 0 && cpu_has_divec) {
1521 #ifdef CONFIG_CPU_MICROMIPS
1522                 unsigned long jump_mask = ~((1 << 27) - 1);
1523 #else
1524                 unsigned long jump_mask = ~((1 << 28) - 1);
1525 #endif
1526                 u32 *buf = (u32 *)(ebase + 0x200);
1527                 unsigned int k0 = 26;
1528                 if ((handler & jump_mask) == ((ebase + 0x200) & jump_mask)) {
1529                         uasm_i_j(&buf, handler & ~jump_mask);
1530                         uasm_i_nop(&buf);
1531                 } else {
1532                         UASM_i_LA(&buf, k0, handler);
1533                         uasm_i_jr(&buf, k0);
1534                         uasm_i_nop(&buf);
1535                 }
1536                 local_flush_icache_range(ebase + 0x200, (unsigned long)buf);
1537         }
1538         return (void *)old_handler;
1539 }
1540
1541 static void do_default_vi(void)
1542 {
1543         show_regs(get_irq_regs());
1544         panic("Caught unexpected vectored interrupt.");
1545 }
1546
1547 static void *set_vi_srs_handler(int n, vi_handler_t addr, int srs)
1548 {
1549         unsigned long handler;
1550         unsigned long old_handler = vi_handlers[n];
1551         int srssets = current_cpu_data.srsets;
1552         u16 *h;
1553         unsigned char *b;
1554
1555         BUG_ON(!cpu_has_veic && !cpu_has_vint);
1556         BUG_ON((n < 0) && (n > 9));
1557
1558         if (addr == NULL) {
1559                 handler = (unsigned long) do_default_vi;
1560                 srs = 0;
1561         } else
1562                 handler = (unsigned long) addr;
1563         vi_handlers[n] = handler;
1564
1565         b = (unsigned char *)(ebase + 0x200 + n*VECTORSPACING);
1566
1567         if (srs >= srssets)
1568                 panic("Shadow register set %d not supported", srs);
1569
1570         if (cpu_has_veic) {
1571                 if (board_bind_eic_interrupt)
1572                         board_bind_eic_interrupt(n, srs);
1573         } else if (cpu_has_vint) {
1574                 /* SRSMap is only defined if shadow sets are implemented */
1575                 if (srssets > 1)
1576                         change_c0_srsmap(0xf << n*4, srs << n*4);
1577         }
1578
1579         if (srs == 0) {
1580                 /*
1581                  * If no shadow set is selected then use the default handler
1582                  * that does normal register saving and standard interrupt exit
1583                  */
1584                 extern char except_vec_vi, except_vec_vi_lui;
1585                 extern char except_vec_vi_ori, except_vec_vi_end;
1586                 extern char rollback_except_vec_vi;
1587                 char *vec_start = using_rollback_handler() ?
1588                         &rollback_except_vec_vi : &except_vec_vi;
1589 #ifdef CONFIG_MIPS_MT_SMTC
1590                 /*
1591                  * We need to provide the SMTC vectored interrupt handler
1592                  * not only with the address of the handler, but with the
1593                  * Status.IM bit to be masked before going there.
1594                  */
1595                 extern char except_vec_vi_mori;
1596 #if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_BIG_ENDIAN)
1597                 const int mori_offset = &except_vec_vi_mori - vec_start + 2;
1598 #else
1599                 const int mori_offset = &except_vec_vi_mori - vec_start;
1600 #endif
1601 #endif /* CONFIG_MIPS_MT_SMTC */
1602 #if defined(CONFIG_CPU_MICROMIPS) || defined(CONFIG_CPU_BIG_ENDIAN)
1603                 const int lui_offset = &except_vec_vi_lui - vec_start + 2;
1604                 const int ori_offset = &except_vec_vi_ori - vec_start + 2;
1605 #else
1606                 const int lui_offset = &except_vec_vi_lui - vec_start;
1607                 const int ori_offset = &except_vec_vi_ori - vec_start;
1608 #endif
1609                 const int handler_len = &except_vec_vi_end - vec_start;
1610
1611                 if (handler_len > VECTORSPACING) {
1612                         /*
1613                          * Sigh... panicing won't help as the console
1614                          * is probably not configured :(
1615                          */
1616                         panic("VECTORSPACING too small");
1617                 }
1618
1619                 set_handler(((unsigned long)b - ebase), vec_start,
1620 #ifdef CONFIG_CPU_MICROMIPS
1621                                 (handler_len - 1));
1622 #else
1623                                 handler_len);
1624 #endif
1625 #ifdef CONFIG_MIPS_MT_SMTC
1626                 BUG_ON(n > 7);  /* Vector index %d exceeds SMTC maximum. */
1627
1628                 h = (u16 *)(b + mori_offset);
1629                 *h = (0x100 << n);
1630 #endif /* CONFIG_MIPS_MT_SMTC */
1631                 h = (u16 *)(b + lui_offset);
1632                 *h = (handler >> 16) & 0xffff;
1633                 h = (u16 *)(b + ori_offset);
1634                 *h = (handler & 0xffff);
1635                 local_flush_icache_range((unsigned long)b,
1636                                          (unsigned long)(b+handler_len));
1637         }
1638         else {
1639                 /*
1640                  * In other cases jump directly to the interrupt handler. It
1641                  * is the handler's responsibility to save registers if required
1642                  * (eg hi/lo) and return from the exception using "eret".
1643                  */
1644                 u32 insn;
1645
1646                 h = (u16 *)b;
1647                 /* j handler */
1648 #ifdef CONFIG_CPU_MICROMIPS
1649                 insn = 0xd4000000 | (((u32)handler & 0x07ffffff) >> 1);
1650 #else
1651                 insn = 0x08000000 | (((u32)handler & 0x0fffffff) >> 2);
1652 #endif
1653                 h[0] = (insn >> 16) & 0xffff;
1654                 h[1] = insn & 0xffff;
1655                 h[2] = 0;
1656                 h[3] = 0;
1657                 local_flush_icache_range((unsigned long)b,
1658                                          (unsigned long)(b+8));
1659         }
1660
1661         return (void *)old_handler;
1662 }
1663
1664 void *set_vi_handler(int n, vi_handler_t addr)
1665 {
1666         return set_vi_srs_handler(n, addr, 0);
1667 }
1668
1669 extern void tlb_init(void);
1670
1671 /*
1672  * Timer interrupt
1673  */
1674 int cp0_compare_irq;
1675 EXPORT_SYMBOL_GPL(cp0_compare_irq);
1676 int cp0_compare_irq_shift;
1677
1678 /*
1679  * Performance counter IRQ or -1 if shared with timer
1680  */
1681 int cp0_perfcount_irq;
1682 EXPORT_SYMBOL_GPL(cp0_perfcount_irq);
1683
1684 static int noulri;
1685
1686 static int __init ulri_disable(char *s)
1687 {
1688         pr_info("Disabling ulri\n");
1689         noulri = 1;
1690
1691         return 1;
1692 }
1693 __setup("noulri", ulri_disable);
1694
1695 void per_cpu_trap_init(bool is_boot_cpu)
1696 {
1697         unsigned int cpu = smp_processor_id();
1698         unsigned int status_set = ST0_CU0;
1699         unsigned int hwrena = cpu_hwrena_impl_bits;
1700 #ifdef CONFIG_MIPS_MT_SMTC
1701         int secondaryTC = 0;
1702         int bootTC = (cpu == 0);
1703
1704         /*
1705          * Only do per_cpu_trap_init() for first TC of Each VPE.
1706          * Note that this hack assumes that the SMTC init code
1707          * assigns TCs consecutively and in ascending order.
1708          */
1709
1710         if (((read_c0_tcbind() & TCBIND_CURTC) != 0) &&
1711             ((read_c0_tcbind() & TCBIND_CURVPE) == cpu_data[cpu - 1].vpe_id))
1712                 secondaryTC = 1;
1713 #endif /* CONFIG_MIPS_MT_SMTC */
1714
1715         /*
1716          * Disable coprocessors and select 32-bit or 64-bit addressing
1717          * and the 16/32 or 32/32 FPR register model.  Reset the BEV
1718          * flag that some firmware may have left set and the TS bit (for
1719          * IP27).  Set XX for ISA IV code to work.
1720          */
1721 #ifdef CONFIG_64BIT
1722         status_set |= ST0_FR|ST0_KX|ST0_SX|ST0_UX;
1723 #endif
1724         if (current_cpu_data.isa_level & MIPS_CPU_ISA_IV)
1725                 status_set |= ST0_XX;
1726         if (cpu_has_dsp)
1727                 status_set |= ST0_MX;
1728
1729         change_c0_status(ST0_CU|ST0_MX|ST0_RE|ST0_FR|ST0_BEV|ST0_TS|ST0_KX|ST0_SX|ST0_UX,
1730                          status_set);
1731
1732         if (cpu_has_mips_r2)
1733                 hwrena |= 0x0000000f;
1734
1735         if (!noulri && cpu_has_userlocal)
1736                 hwrena |= (1 << 29);
1737
1738         if (hwrena)
1739                 write_c0_hwrena(hwrena);
1740
1741 #ifdef CONFIG_MIPS_MT_SMTC
1742         if (!secondaryTC) {
1743 #endif /* CONFIG_MIPS_MT_SMTC */
1744
1745         if (cpu_has_veic || cpu_has_vint) {
1746                 unsigned long sr = set_c0_status(ST0_BEV);
1747                 write_c0_ebase(ebase);
1748                 write_c0_status(sr);
1749                 /* Setting vector spacing enables EI/VI mode  */
1750                 change_c0_intctl(0x3e0, VECTORSPACING);
1751         }
1752         if (cpu_has_divec) {
1753                 if (cpu_has_mipsmt) {
1754                         unsigned int vpflags = dvpe();
1755                         set_c0_cause(CAUSEF_IV);
1756                         evpe(vpflags);
1757                 } else
1758                         set_c0_cause(CAUSEF_IV);
1759         }
1760
1761         /*
1762          * Before R2 both interrupt numbers were fixed to 7, so on R2 only:
1763          *
1764          *  o read IntCtl.IPTI to determine the timer interrupt
1765          *  o read IntCtl.IPPCI to determine the performance counter interrupt
1766          */
1767         if (cpu_has_mips_r2) {
1768                 cp0_compare_irq_shift = CAUSEB_TI - CAUSEB_IP;
1769                 cp0_compare_irq = (read_c0_intctl() >> INTCTLB_IPTI) & 7;
1770                 cp0_perfcount_irq = (read_c0_intctl() >> INTCTLB_IPPCI) & 7;
1771                 if (cp0_perfcount_irq == cp0_compare_irq)
1772                         cp0_perfcount_irq = -1;
1773         } else {
1774                 cp0_compare_irq = CP0_LEGACY_COMPARE_IRQ;
1775                 cp0_compare_irq_shift = CP0_LEGACY_PERFCNT_IRQ;
1776                 cp0_perfcount_irq = -1;
1777         }
1778
1779 #ifdef CONFIG_MIPS_MT_SMTC
1780         }
1781 #endif /* CONFIG_MIPS_MT_SMTC */
1782
1783         if (!cpu_data[cpu].asid_cache)
1784                 cpu_data[cpu].asid_cache = ASID_FIRST_VERSION;
1785
1786         atomic_inc(&init_mm.mm_count);
1787         current->active_mm = &init_mm;
1788         BUG_ON(current->mm);
1789         enter_lazy_tlb(&init_mm, current);
1790
1791 #ifdef CONFIG_MIPS_MT_SMTC
1792         if (bootTC) {
1793 #endif /* CONFIG_MIPS_MT_SMTC */
1794                 /* Boot CPU's cache setup in setup_arch(). */
1795                 if (!is_boot_cpu)
1796                         cpu_cache_init();
1797                 tlb_init();
1798 #ifdef CONFIG_MIPS_MT_SMTC
1799         } else if (!secondaryTC) {
1800                 /*
1801                  * First TC in non-boot VPE must do subset of tlb_init()
1802                  * for MMU countrol registers.
1803                  */
1804                 write_c0_pagemask(PM_DEFAULT_MASK);
1805                 write_c0_wired(0);
1806         }
1807 #endif /* CONFIG_MIPS_MT_SMTC */
1808         TLBMISS_HANDLER_SETUP();
1809 }
1810
1811 /* Install CPU exception handler */
1812 void set_handler(unsigned long offset, void *addr, unsigned long size)
1813 {
1814 #ifdef CONFIG_CPU_MICROMIPS
1815         memcpy((void *)(ebase + offset), ((unsigned char *)addr - 1), size);
1816 #else
1817         memcpy((void *)(ebase + offset), addr, size);
1818 #endif
1819         local_flush_icache_range(ebase + offset, ebase + offset + size);
1820 }
1821
1822 static char panic_null_cerr[] =
1823         "Trying to set NULL cache error exception handler";
1824
1825 /*
1826  * Install uncached CPU exception handler.
1827  * This is suitable only for the cache error exception which is the only
1828  * exception handler that is being run uncached.
1829  */
1830 void set_uncached_handler(unsigned long offset, void *addr,
1831         unsigned long size)
1832 {
1833         unsigned long uncached_ebase = CKSEG1ADDR(ebase);
1834
1835         if (!addr)
1836                 panic(panic_null_cerr);
1837
1838         memcpy((void *)(uncached_ebase + offset), addr, size);
1839 }
1840
1841 static int __initdata rdhwr_noopt;
1842 static int __init set_rdhwr_noopt(char *str)
1843 {
1844         rdhwr_noopt = 1;
1845         return 1;
1846 }
1847
1848 __setup("rdhwr_noopt", set_rdhwr_noopt);
1849
1850 void __init trap_init(void)
1851 {
1852         extern char except_vec3_generic;
1853         extern char except_vec4;
1854         extern char except_vec3_r4000;
1855         unsigned long i;
1856
1857         check_wait();
1858
1859 #if defined(CONFIG_KGDB)
1860         if (kgdb_early_setup)
1861                 return; /* Already done */
1862 #endif
1863
1864         if (cpu_has_veic || cpu_has_vint) {
1865                 unsigned long size = 0x200 + VECTORSPACING*64;
1866                 ebase = (unsigned long)
1867                         __alloc_bootmem(size, 1 << fls(size), 0);
1868         } else {
1869 #ifdef CONFIG_KVM_GUEST
1870 #define KVM_GUEST_KSEG0     0x40000000
1871         ebase = KVM_GUEST_KSEG0;
1872 #else
1873         ebase = CKSEG0;
1874 #endif
1875                 if (cpu_has_mips_r2)
1876                         ebase += (read_c0_ebase() & 0x3ffff000);
1877         }
1878
1879         if (cpu_has_mmips) {
1880                 unsigned int config3 = read_c0_config3();
1881
1882                 if (IS_ENABLED(CONFIG_CPU_MICROMIPS))
1883                         write_c0_config3(config3 | MIPS_CONF3_ISA_OE);
1884                 else
1885                         write_c0_config3(config3 & ~MIPS_CONF3_ISA_OE);
1886         }
1887
1888         if (board_ebase_setup)
1889                 board_ebase_setup();
1890         per_cpu_trap_init(true);
1891
1892         /*
1893          * Copy the generic exception handlers to their final destination.
1894          * This will be overriden later as suitable for a particular
1895          * configuration.
1896          */
1897         set_handler(0x180, &except_vec3_generic, 0x80);
1898
1899         /*
1900          * Setup default vectors
1901          */
1902         for (i = 0; i <= 31; i++)
1903                 set_except_vector(i, handle_reserved);
1904
1905         /*
1906          * Copy the EJTAG debug exception vector handler code to it's final
1907          * destination.
1908          */
1909         if (cpu_has_ejtag && board_ejtag_handler_setup)
1910                 board_ejtag_handler_setup();
1911
1912         /*
1913          * Only some CPUs have the watch exceptions.
1914          */
1915         if (cpu_has_watch)
1916                 set_except_vector(23, handle_watch);
1917
1918         /*
1919          * Initialise interrupt handlers
1920          */
1921         if (cpu_has_veic || cpu_has_vint) {
1922                 int nvec = cpu_has_veic ? 64 : 8;
1923                 for (i = 0; i < nvec; i++)
1924                         set_vi_handler(i, NULL);
1925         }
1926         else if (cpu_has_divec)
1927                 set_handler(0x200, &except_vec4, 0x8);
1928
1929         /*
1930          * Some CPUs can enable/disable for cache parity detection, but does
1931          * it different ways.
1932          */
1933         parity_protection_init();
1934
1935         /*
1936          * The Data Bus Errors / Instruction Bus Errors are signaled
1937          * by external hardware.  Therefore these two exceptions
1938          * may have board specific handlers.
1939          */
1940         if (board_be_init)
1941                 board_be_init();
1942
1943         set_except_vector(0, using_rollback_handler() ? rollback_handle_int
1944                                                       : handle_int);
1945         set_except_vector(1, handle_tlbm);
1946         set_except_vector(2, handle_tlbl);
1947         set_except_vector(3, handle_tlbs);
1948
1949         set_except_vector(4, handle_adel);
1950         set_except_vector(5, handle_ades);
1951
1952         set_except_vector(6, handle_ibe);
1953         set_except_vector(7, handle_dbe);
1954
1955         set_except_vector(8, handle_sys);
1956         set_except_vector(9, handle_bp);
1957         set_except_vector(10, rdhwr_noopt ? handle_ri :
1958                           (cpu_has_vtag_icache ?
1959                            handle_ri_rdhwr_vivt : handle_ri_rdhwr));
1960         set_except_vector(11, handle_cpu);
1961         set_except_vector(12, handle_ov);
1962         set_except_vector(13, handle_tr);
1963
1964         if (current_cpu_type() == CPU_R6000 ||
1965             current_cpu_type() == CPU_R6000A) {
1966                 /*
1967                  * The R6000 is the only R-series CPU that features a machine
1968                  * check exception (similar to the R4000 cache error) and
1969                  * unaligned ldc1/sdc1 exception.  The handlers have not been
1970                  * written yet.  Well, anyway there is no R6000 machine on the
1971                  * current list of targets for Linux/MIPS.
1972                  * (Duh, crap, there is someone with a triple R6k machine)
1973                  */
1974                 //set_except_vector(14, handle_mc);
1975                 //set_except_vector(15, handle_ndc);
1976         }
1977
1978
1979         if (board_nmi_handler_setup)
1980                 board_nmi_handler_setup();
1981
1982         if (cpu_has_fpu && !cpu_has_nofpuex)
1983                 set_except_vector(15, handle_fpe);
1984
1985         set_except_vector(22, handle_mdmx);
1986
1987         if (cpu_has_mcheck)
1988                 set_except_vector(24, handle_mcheck);
1989
1990         if (cpu_has_mipsmt)
1991                 set_except_vector(25, handle_mt);
1992
1993         set_except_vector(26, handle_dsp);
1994
1995         if (board_cache_error_setup)
1996                 board_cache_error_setup();
1997
1998         if (cpu_has_vce)
1999                 /* Special exception: R4[04]00 uses also the divec space. */
2000                 set_handler(0x180, &except_vec3_r4000, 0x100);
2001         else if (cpu_has_4kex)
2002                 set_handler(0x180, &except_vec3_generic, 0x80);
2003         else
2004                 set_handler(0x080, &except_vec3_generic, 0x80);
2005
2006         local_flush_icache_range(ebase, ebase + 0x400);
2007
2008         sort_extable(__start___dbe_table, __stop___dbe_table);
2009
2010         cu2_notifier(default_cu2_call, 0x80000000);     /* Run last  */
2011 }