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