target-mips/helper.c

   1 /*
   2  *  MIPS emulation helpers for qemu.
   3  *
   4  *  Copyright (c) 2004-2005 Jocelyn Mayer
   5  *
   6  * This library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2 of the License, or (at your option) any later version.
  10  *
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU Lesser General Public
  17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  18  */
  19 #include <stdarg.h>
  20 #include <stdlib.h>
  21 #include <stdio.h>
  22 #include <string.h>
  23 #include <inttypes.h>
  24 #include <signal.h>
  25
  26 #include "cpu.h"
  27
  28 enum {
  29     TLBRET_DIRTY = -4,
  30     TLBRET_INVALID = -3,
  31     TLBRET_NOMATCH = -2,
  32     TLBRET_BADADDR = -1,
  33     TLBRET_MATCH = 0
  34 };
  35
  36 #if !defined(CONFIG_USER_ONLY)
  37
  38 /* no MMU emulation */
  39 int no_mmu_map_address (CPUState *env, target_phys_addr_t *physical, int *prot,
  40                         target_ulong address, int rw, int access_type)
  41 {
  42     *physical = address;
  43     *prot = PAGE_READ | PAGE_WRITE;
  44     return TLBRET_MATCH;
  45 }
  46
  47 /* fixed mapping MMU emulation */
  48 int fixed_mmu_map_address (CPUState *env, target_phys_addr_t *physical, int *prot,
  49                            target_ulong address, int rw, int access_type)
  50 {
  51     if (address <= (int32_t)0x7FFFFFFFUL) {
  52         if (!(env->CP0_Status & (1 << CP0St_ERL)))
  53             *physical = address + 0x40000000UL;
  54         else
  55             *physical = address;
  56     } else if (address <= (int32_t)0xBFFFFFFFUL)
  57         *physical = address & 0x1FFFFFFF;
  58     else
  59         *physical = address;
  60
  61     *prot = PAGE_READ | PAGE_WRITE;
  62     return TLBRET_MATCH;
  63 }
  64
  65 /* MIPS32/MIPS64 R4000-style MMU emulation */
  66 int r4k_map_address (CPUState *env, target_phys_addr_t *physical, int *prot,
  67                      target_ulong address, int rw, int access_type)
  68 {
  69     uint8_t ASID = env->CP0_EntryHi & 0xFF;
  70     int i;
  71
  72     for (i = 0; i < env->tlb->tlb_in_use; i++) {
  73         r4k_tlb_t *tlb = &env->tlb->mmu.r4k.tlb[i];
  74         /* 1k pages are not supported. */
  75         target_ulong mask = tlb->PageMask | ~(TARGET_PAGE_MASK << 1);
  76         target_ulong tag = address & ~mask;
  77         target_ulong VPN = tlb->VPN & ~mask;
  78 #if defined(TARGET_MIPS64)
  79         tag &= env->SEGMask;
  80 #endif
  81
  82         /* Check ASID, virtual page number & size */
  83         if ((tlb->G == 1 || tlb->ASID == ASID) && VPN == tag) {
  84             /* TLB match */
  85             int n = !!(address & mask & ~(mask >> 1));
  86             /* Check access rights */
  87             if (!(n ? tlb->V1 : tlb->V0))
  88                 return TLBRET_INVALID;
  89             if (rw == 0 || (n ? tlb->D1 : tlb->D0)) {
  90                 *physical = tlb->PFN[n] | (address & (mask >> 1));
  91                 *prot = PAGE_READ;
  92                 if (n ? tlb->D1 : tlb->D0)
  93                     *prot |= PAGE_WRITE;
  94                 return TLBRET_MATCH;
  95             }
  96             return TLBRET_DIRTY;
  97         }
  98     }
  99     return TLBRET_NOMATCH;
 100 }
 101
 102 static int get_physical_address (CPUState *env, target_phys_addr_t *physical,
 103                                 int *prot, target_ulong address,
 104                                 int rw, int access_type)
 105 {
 106     /* User mode can only access useg/xuseg */
 107     int user_mode = (env->hflags & MIPS_HFLAG_MODE) == MIPS_HFLAG_UM;
 108     int supervisor_mode = (env->hflags & MIPS_HFLAG_MODE) == MIPS_HFLAG_SM;
 109     int kernel_mode = !user_mode && !supervisor_mode;
 110 #if defined(TARGET_MIPS64)
 111     int UX = (env->CP0_Status & (1 << CP0St_UX)) != 0;
 112     int SX = (env->CP0_Status & (1 << CP0St_SX)) != 0;
 113     int KX = (env->CP0_Status & (1 << CP0St_KX)) != 0;
 114 #endif
 115     int ret = TLBRET_MATCH;
 116
 117 #if 0
 118     qemu_log("user mode %d h %08x\n", user_mode, env->hflags);
 119 #endif
 120
 121     if (address <= (int32_t)0x7FFFFFFFUL) {
 122         /* useg */
 123         if (env->CP0_Status & (1 << CP0St_ERL)) {
 124             *physical = address & 0xFFFFFFFF;
 125             *prot = PAGE_READ | PAGE_WRITE;
 126         } else {
 127             ret = env->tlb->map_address(env, physical, prot, address, rw, access_type);
 128         }
 129 #if defined(TARGET_MIPS64)
 130     } else if (address < 0x4000000000000000ULL) {
 131         /* xuseg */
 132         if (UX && address <= (0x3FFFFFFFFFFFFFFFULL & env->SEGMask)) {
 133             ret = env->tlb->map_address(env, physical, prot, address, rw, access_type);
 134         } else {
 135             ret = TLBRET_BADADDR;
 136         }
 137     } else if (address < 0x8000000000000000ULL) {
 138         /* xsseg */
 139         if ((supervisor_mode || kernel_mode) &&
 140             SX && address <= (0x7FFFFFFFFFFFFFFFULL & env->SEGMask)) {
 141             ret = env->tlb->map_address(env, physical, prot, address, rw, access_type);
 142         } else {
 143             ret = TLBRET_BADADDR;
 144         }
 145     } else if (address < 0xC000000000000000ULL) {
 146         /* xkphys */
 147         if (kernel_mode && KX &&
 148             (address & 0x07FFFFFFFFFFFFFFULL) <= env->PAMask) {
 149             *physical = address & env->PAMask;
 150             *prot = PAGE_READ | PAGE_WRITE;
 151         } else {
 152             ret = TLBRET_BADADDR;
 153         }
 154     } else if (address < 0xFFFFFFFF80000000ULL) {
 155         /* xkseg */
 156         if (kernel_mode && KX &&
 157             address <= (0xFFFFFFFF7FFFFFFFULL & env->SEGMask)) {
 158             ret = env->tlb->map_address(env, physical, prot, address, rw, access_type);
 159         } else {
 160             ret = TLBRET_BADADDR;
 161         }
 162 #endif
 163     } else if (address < (int32_t)0xA0000000UL) {
 164         /* kseg0 */
 165         if (kernel_mode) {
 166             *physical = address - (int32_t)0x80000000UL;
 167             *prot = PAGE_READ | PAGE_WRITE;
 168         } else {
 169             ret = TLBRET_BADADDR;
 170         }
 171     } else if (address < (int32_t)0xC0000000UL) {
 172         /* kseg1 */
 173         if (kernel_mode) {
 174             *physical = address - (int32_t)0xA0000000UL;
 175             *prot = PAGE_READ | PAGE_WRITE;
 176         } else {
 177             ret = TLBRET_BADADDR;
 178         }
 179     } else if (address < (int32_t)0xE0000000UL) {
 180         /* sseg (kseg2) */
 181         if (supervisor_mode || kernel_mode) {
 182             ret = env->tlb->map_address(env, physical, prot, address, rw, access_type);
 183         } else {
 184             ret = TLBRET_BADADDR;
 185         }
 186     } else {
 187         /* kseg3 */
 188         /* XXX: debug segment is not emulated */
 189         if (kernel_mode) {
 190             ret = env->tlb->map_address(env, physical, prot, address, rw, access_type);
 191         } else {
 192             ret = TLBRET_BADADDR;
 193         }
 194     }
 195 #if 0
 196     qemu_log(TARGET_FMT_lx " %d %d => " TARGET_FMT_lx " %d (%d)\n",
 197             address, rw, access_type, *physical, *prot, ret);
 198 #endif
 199
 200     return ret;
 201 }
 202 #endif
 203
 204 static void raise_mmu_exception(CPUState *env, target_ulong address,
 205                                 int rw, int tlb_error)
 206 {
 207     int exception = 0, error_code = 0;
 208
 209     switch (tlb_error) {
 210     default:
 211     case TLBRET_BADADDR:
 212         /* Reference to kernel address from user mode or supervisor mode */
 213         /* Reference to supervisor address from user mode */
 214         if (rw)
 215             exception = EXCP_AdES;
 216         else
 217             exception = EXCP_AdEL;
 218         break;
 219     case TLBRET_NOMATCH:
 220         /* No TLB match for a mapped address */
 221         if (rw)
 222             exception = EXCP_TLBS;
 223         else
 224             exception = EXCP_TLBL;
 225         error_code = 1;
 226         break;
 227     case TLBRET_INVALID:
 228         /* TLB match with no valid bit */
 229         if (rw)
 230             exception = EXCP_TLBS;
 231         else
 232             exception = EXCP_TLBL;
 233         break;
 234     case TLBRET_DIRTY:
 235         /* TLB match but 'D' bit is cleared */
 236         exception = EXCP_LTLBL;
 237         break;
 238
 239     }
 240     /* Raise exception */
 241     env->CP0_BadVAddr = address;
 242     env->CP0_Context = (env->CP0_Context & ~0x007fffff) |
 243                        ((address >> 9) & 0x007ffff0);
 244     env->CP0_EntryHi =
 245         (env->CP0_EntryHi & 0xFF) | (address & (TARGET_PAGE_MASK << 1));
 246 #if defined(TARGET_MIPS64)
 247     env->CP0_EntryHi &= env->SEGMask;
 248     env->CP0_XContext = (env->CP0_XContext & ((~0ULL) << (env->SEGBITS - 7))) |
 249                         ((address & 0xC00000000000ULL) >> (55 - env->SEGBITS)) |
 250                         ((address & ((1ULL << env->SEGBITS) - 1) & 0xFFFFFFFFFFFFE000ULL) >> 9);
 251 #endif
 252     env->exception_index = exception;
 253     env->error_code = error_code;
 254 }
 255
 256 #if !defined(CONFIG_USER_ONLY)
 257 target_phys_addr_t cpu_get_phys_page_debug(CPUState *env, target_ulong addr)
 258 {
 259     target_phys_addr_t phys_addr;
 260     int prot;
 261
 262     if (get_physical_address(env, &phys_addr, &prot, addr, 0, ACCESS_INT) != 0)
 263         return -1;
 264     return phys_addr;
 265 }
 266 #endif
 267
 268 int cpu_mips_handle_mmu_fault (CPUState *env, target_ulong address, int rw,
 269                                int mmu_idx)
 270 {
 271 #if !defined(CONFIG_USER_ONLY)
 272     target_phys_addr_t physical;
 273     int prot;
 274     int access_type;
 275 #endif
 276     int ret = 0;
 277
 278 #if 0
 279     log_cpu_state(env, 0);
 280 #endif
 281     qemu_log("%s pc " TARGET_FMT_lx " ad " TARGET_FMT_lx " rw %d mmu_idx %d\n",
 282               __func__, env->active_tc.PC, address, rw, mmu_idx);
 283
 284     rw &= 1;
 285
 286     /* data access */
 287 #if !defined(CONFIG_USER_ONLY)
 288     /* XXX: put correct access by using cpu_restore_state()
 289        correctly */
 290     access_type = ACCESS_INT;
 291     ret = get_physical_address(env, &physical, &prot,
 292                                address, rw, access_type);
 293     qemu_log("%s address=" TARGET_FMT_lx " ret %d physical " TARGET_FMT_plx " prot %d\n",
 294               __func__, address, ret, physical, prot);
 295     if (ret == TLBRET_MATCH) {
 296         tlb_set_page(env, address & TARGET_PAGE_MASK,
 297                      physical & TARGET_PAGE_MASK, prot | PAGE_EXEC,
 298                      mmu_idx, TARGET_PAGE_SIZE);
 299         ret = 0;
 300     } else if (ret < 0)
 301 #endif
 302     {
 303         raise_mmu_exception(env, address, rw, ret);
 304         ret = 1;
 305     }
 306
 307     return ret;
 308 }
 309
 310 #if !defined(CONFIG_USER_ONLY)
 311 target_phys_addr_t cpu_mips_translate_address(CPUState *env, target_ulong address, int rw)
 312 {
 313     target_phys_addr_t physical;
 314     int prot;
 315     int access_type;
 316     int ret = 0;
 317
 318     rw &= 1;
 319
 320     /* data access */
 321     access_type = ACCESS_INT;
 322     ret = get_physical_address(env, &physical, &prot,
 323                                address, rw, access_type);
 324     if (ret != TLBRET_MATCH) {
 325         raise_mmu_exception(env, address, rw, ret);
 326         return -1LL;
 327     } else {
 328         return physical;
 329     }
 330 }
 331 #endif
 332
 333 static const char * const excp_names[EXCP_LAST + 1] = {
 334     [EXCP_RESET] = "reset",
 335     [EXCP_SRESET] = "soft reset",
 336     [EXCP_DSS] = "debug single step",
 337     [EXCP_DINT] = "debug interrupt",
 338     [EXCP_NMI] = "non-maskable interrupt",
 339     [EXCP_MCHECK] = "machine check",
 340     [EXCP_EXT_INTERRUPT] = "interrupt",
 341     [EXCP_DFWATCH] = "deferred watchpoint",
 342     [EXCP_DIB] = "debug instruction breakpoint",
 343     [EXCP_IWATCH] = "instruction fetch watchpoint",
 344     [EXCP_AdEL] = "address error load",
 345     [EXCP_AdES] = "address error store",
 346     [EXCP_TLBF] = "TLB refill",
 347     [EXCP_IBE] = "instruction bus error",
 348     [EXCP_DBp] = "debug breakpoint",
 349     [EXCP_SYSCALL] = "syscall",
 350     [EXCP_BREAK] = "break",
 351     [EXCP_CpU] = "coprocessor unusable",
 352     [EXCP_RI] = "reserved instruction",
 353     [EXCP_OVERFLOW] = "arithmetic overflow",
 354     [EXCP_TRAP] = "trap",
 355     [EXCP_FPE] = "floating point",
 356     [EXCP_DDBS] = "debug data break store",
 357     [EXCP_DWATCH] = "data watchpoint",
 358     [EXCP_LTLBL] = "TLB modify",
 359     [EXCP_TLBL] = "TLB load",
 360     [EXCP_TLBS] = "TLB store",
 361     [EXCP_DBE] = "data bus error",
 362     [EXCP_DDBL] = "debug data break load",
 363     [EXCP_THREAD] = "thread",
 364     [EXCP_MDMX] = "MDMX",
 365     [EXCP_C2E] = "precise coprocessor 2",
 366     [EXCP_CACHE] = "cache error",
 367 };
 368
 369 #if !defined(CONFIG_USER_ONLY)
 370 static target_ulong exception_resume_pc (CPUState *env)
 371 {
 372     target_ulong bad_pc;
 373     target_ulong isa_mode;
 374
 375     isa_mode = !!(env->hflags & MIPS_HFLAG_M16);
 376     bad_pc = env->active_tc.PC | isa_mode;
 377     if (env->hflags & MIPS_HFLAG_BMASK) {
 378         /* If the exception was raised from a delay slot, come back to
 379            the jump.  */
 380         bad_pc -= (env->hflags & MIPS_HFLAG_B16 ? 2 : 4);
 381     }
 382
 383     return bad_pc;
 384 }
 385
 386 static void set_hflags_for_handler (CPUState *env)
 387 {
 388     /* Exception handlers are entered in 32-bit mode.  */
 389     env->hflags &= ~(MIPS_HFLAG_M16);
 390     /* ...except that microMIPS lets you choose.  */
 391     if (env->insn_flags & ASE_MICROMIPS) {
 392         env->hflags |= (!!(env->CP0_Config3
 393                            & (1 << CP0C3_ISA_ON_EXC))
 394                         << MIPS_HFLAG_M16_SHIFT);
 395     }
 396 }
 397 #endif
 398
 399 void do_interrupt (CPUState *env)
 400 {
 401 #if !defined(CONFIG_USER_ONLY)
 402     target_ulong offset;
 403     int cause = -1;
 404     const char *name;
 405
 406     if (qemu_log_enabled() && env->exception_index != EXCP_EXT_INTERRUPT) {
 407         if (env->exception_index < 0 || env->exception_index > EXCP_LAST)
 408             name = "unknown";
 409         else
 410             name = excp_names[env->exception_index];
 411
 412         qemu_log("%s enter: PC " TARGET_FMT_lx " EPC " TARGET_FMT_lx " %s exception\n",
 413                  __func__, env->active_tc.PC, env->CP0_EPC, name);
 414     }
 415     if (env->exception_index == EXCP_EXT_INTERRUPT &&
 416         (env->hflags & MIPS_HFLAG_DM))
 417         env->exception_index = EXCP_DINT;
 418     offset = 0x180;
 419     switch (env->exception_index) {
 420     case EXCP_DSS:
 421         env->CP0_Debug |= 1 << CP0DB_DSS;
 422         /* Debug single step cannot be raised inside a delay slot and
 423            resume will always occur on the next instruction
 424            (but we assume the pc has always been updated during
 425            code translation). */
 426         env->CP0_DEPC = env->active_tc.PC | !!(env->hflags & MIPS_HFLAG_M16);
 427         goto enter_debug_mode;
 428     case EXCP_DINT:
 429         env->CP0_Debug |= 1 << CP0DB_DINT;
 430         goto set_DEPC;
 431     case EXCP_DIB:
 432         env->CP0_Debug |= 1 << CP0DB_DIB;
 433         goto set_DEPC;
 434     case EXCP_DBp:
 435         env->CP0_Debug |= 1 << CP0DB_DBp;
 436         goto set_DEPC;
 437     case EXCP_DDBS:
 438         env->CP0_Debug |= 1 << CP0DB_DDBS;
 439         goto set_DEPC;
 440     case EXCP_DDBL:
 441         env->CP0_Debug |= 1 << CP0DB_DDBL;
 442     set_DEPC:
 443         env->CP0_DEPC = exception_resume_pc(env);
 444         env->hflags &= ~MIPS_HFLAG_BMASK;
 445  enter_debug_mode:
 446         env->hflags |= MIPS_HFLAG_DM | MIPS_HFLAG_64 | MIPS_HFLAG_CP0;
 447         env->hflags &= ~(MIPS_HFLAG_KSU);
 448         /* EJTAG probe trap enable is not implemented... */
 449         if (!(env->CP0_Status & (1 << CP0St_EXL)))
 450             env->CP0_Cause &= ~(1 << CP0Ca_BD);
 451         env->active_tc.PC = (int32_t)0xBFC00480;
 452         set_hflags_for_handler(env);
 453         break;
 454     case EXCP_RESET:
 455         cpu_reset(env);
 456         break;
 457     case EXCP_SRESET:
 458         env->CP0_Status |= (1 << CP0St_SR);
 459         memset(env->CP0_WatchLo, 0, sizeof(*env->CP0_WatchLo));
 460         goto set_error_EPC;
 461     case EXCP_NMI:
 462         env->CP0_Status |= (1 << CP0St_NMI);
 463  set_error_EPC:
 464         env->CP0_ErrorEPC = exception_resume_pc(env);
 465         env->hflags &= ~MIPS_HFLAG_BMASK;
 466         env->CP0_Status |= (1 << CP0St_ERL) | (1 << CP0St_BEV);
 467         env->hflags |= MIPS_HFLAG_64 | MIPS_HFLAG_CP0;
 468         env->hflags &= ~(MIPS_HFLAG_KSU);
 469         if (!(env->CP0_Status & (1 << CP0St_EXL)))
 470             env->CP0_Cause &= ~(1 << CP0Ca_BD);
 471         env->active_tc.PC = (int32_t)0xBFC00000;
 472         set_hflags_for_handler(env);
 473         break;
 474     case EXCP_EXT_INTERRUPT:
 475         cause = 0;
 476         if (env->CP0_Cause & (1 << CP0Ca_IV))
 477             offset = 0x200;
 478
 479         if (env->CP0_Config3 & ((1 << CP0C3_VInt) | (1 << CP0C3_VEIC))) {
 480             /* Vectored Interrupts.  */
 481             unsigned int spacing;
 482             unsigned int vector;
 483             unsigned int pending = (env->CP0_Cause & CP0Ca_IP_mask) >> 8;
 484
 485             /* Compute the Vector Spacing.  */
 486             spacing = (env->CP0_IntCtl >> CP0IntCtl_VS) & ((1 << 6) - 1);
 487             spacing <<= 5;
 488
 489             if (env->CP0_Config3 & (1 << CP0C3_VInt)) {
 490                 /* For VInt mode, the MIPS computes the vector internally.  */
 491                 for (vector = 0; vector < 8; vector++) {
 492                     if (pending & 1) {
 493                         /* Found it.  */
 494                         break;
 495                     }
 496                     pending >>= 1;
 497                 }
 498             } else {
 499                 /* For VEIC mode, the external interrupt controller feeds the
 500                    vector throught the CP0Cause IP lines.  */
 501                 vector = pending;
 502             }
 503             offset = 0x200 + vector * spacing;
 504         }
 505         goto set_EPC;
 506     case EXCP_LTLBL:
 507         cause = 1;
 508         goto set_EPC;
 509     case EXCP_TLBL:
 510         cause = 2;
 511         if (env->error_code == 1 && !(env->CP0_Status & (1 << CP0St_EXL))) {
 512 #if defined(TARGET_MIPS64)
 513             int R = env->CP0_BadVAddr >> 62;
 514             int UX = (env->CP0_Status & (1 << CP0St_UX)) != 0;
 515             int SX = (env->CP0_Status & (1 << CP0St_SX)) != 0;
 516             int KX = (env->CP0_Status & (1 << CP0St_KX)) != 0;
 517
 518             if (((R == 0 && UX) || (R == 1 && SX) || (R == 3 && KX)) &&
 519                 (!(env->insn_flags & (INSN_LOONGSON2E | INSN_LOONGSON2F))))
 520                 offset = 0x080;
 521             else
 522 #endif
 523                 offset = 0x000;
 524         }
 525         goto set_EPC;
 526     case EXCP_TLBS:
 527         cause = 3;
 528         if (env->error_code == 1 && !(env->CP0_Status & (1 << CP0St_EXL))) {
 529 #if defined(TARGET_MIPS64)
 530             int R = env->CP0_BadVAddr >> 62;
 531             int UX = (env->CP0_Status & (1 << CP0St_UX)) != 0;
 532             int SX = (env->CP0_Status & (1 << CP0St_SX)) != 0;
 533             int KX = (env->CP0_Status & (1 << CP0St_KX)) != 0;
 534
 535             if (((R == 0 && UX) || (R == 1 && SX) || (R == 3 && KX)) &&
 536                 (!(env->insn_flags & (INSN_LOONGSON2E | INSN_LOONGSON2F))))
 537                 offset = 0x080;
 538             else
 539 #endif
 540                 offset = 0x000;
 541         }
 542         goto set_EPC;
 543     case EXCP_AdEL:
 544         cause = 4;
 545         goto set_EPC;
 546     case EXCP_AdES:
 547         cause = 5;
 548         goto set_EPC;
 549     case EXCP_IBE:
 550         cause = 6;
 551         goto set_EPC;
 552     case EXCP_DBE:
 553         cause = 7;
 554         goto set_EPC;
 555     case EXCP_SYSCALL:
 556         cause = 8;
 557         goto set_EPC;
 558     case EXCP_BREAK:
 559         cause = 9;
 560         goto set_EPC;
 561     case EXCP_RI:
 562         cause = 10;
 563         goto set_EPC;
 564     case EXCP_CpU:
 565         cause = 11;
 566         env->CP0_Cause = (env->CP0_Cause & ~(0x3 << CP0Ca_CE)) |
 567                          (env->error_code << CP0Ca_CE);
 568         goto set_EPC;
 569     case EXCP_OVERFLOW:
 570         cause = 12;
 571         goto set_EPC;
 572     case EXCP_TRAP:
 573         cause = 13;
 574         goto set_EPC;
 575     case EXCP_FPE:
 576         cause = 15;
 577         goto set_EPC;
 578     case EXCP_C2E:
 579         cause = 18;
 580         goto set_EPC;
 581     case EXCP_MDMX:
 582         cause = 22;
 583         goto set_EPC;
 584     case EXCP_DWATCH:
 585         cause = 23;
 586         /* XXX: TODO: manage defered watch exceptions */
 587         goto set_EPC;
 588     case EXCP_MCHECK:
 589         cause = 24;
 590         goto set_EPC;
 591     case EXCP_THREAD:
 592         cause = 25;
 593         goto set_EPC;
 594     case EXCP_CACHE:
 595         cause = 30;
 596         if (env->CP0_Status & (1 << CP0St_BEV)) {
 597             offset = 0x100;
 598         } else {
 599             offset = 0x20000100;
 600         }
 601  set_EPC:
 602         if (!(env->CP0_Status & (1 << CP0St_EXL))) {
 603             env->CP0_EPC = exception_resume_pc(env);
 604             if (env->hflags & MIPS_HFLAG_BMASK) {
 605                 env->CP0_Cause |= (1 << CP0Ca_BD);
 606             } else {
 607                 env->CP0_Cause &= ~(1 << CP0Ca_BD);
 608             }
 609             env->CP0_Status |= (1 << CP0St_EXL);
 610             env->hflags |= MIPS_HFLAG_64 | MIPS_HFLAG_CP0;
 611             env->hflags &= ~(MIPS_HFLAG_KSU);
 612         }
 613         env->hflags &= ~MIPS_HFLAG_BMASK;
 614         if (env->CP0_Status & (1 << CP0St_BEV)) {
 615             env->active_tc.PC = (int32_t)0xBFC00200;
 616         } else {
 617             env->active_tc.PC = (int32_t)(env->CP0_EBase & ~0x3ff);
 618         }
 619         env->active_tc.PC += offset;
 620         set_hflags_for_handler(env);
 621         env->CP0_Cause = (env->CP0_Cause & ~(0x1f << CP0Ca_EC)) | (cause << CP0Ca_EC);
 622         break;
 623     default:
 624         qemu_log("Invalid MIPS exception %d. Exiting\n", env->exception_index);
 625         printf("Invalid MIPS exception %d. Exiting\n", env->exception_index);
 626         exit(1);
 627     }
 628     if (qemu_log_enabled() && env->exception_index != EXCP_EXT_INTERRUPT) {
 629         qemu_log("%s: PC " TARGET_FMT_lx " EPC " TARGET_FMT_lx " cause %d\n"
 630                 "    S %08x C %08x A " TARGET_FMT_lx " D " TARGET_FMT_lx "\n",
 631                 __func__, env->active_tc.PC, env->CP0_EPC, cause,
 632                 env->CP0_Status, env->CP0_Cause, env->CP0_BadVAddr,
 633                 env->CP0_DEPC);
 634     }
 635 #endif
 636     env->exception_index = EXCP_NONE;
 637 }
 638
 639 #if !defined(CONFIG_USER_ONLY)
 640 void r4k_invalidate_tlb (CPUState *env, int idx, int use_extra)
 641 {
 642     r4k_tlb_t *tlb;
 643     target_ulong addr;
 644     target_ulong end;
 645     uint8_t ASID = env->CP0_EntryHi & 0xFF;
 646     target_ulong mask;
 647
 648     tlb = &env->tlb->mmu.r4k.tlb[idx];
 649     /* The qemu TLB is flushed when the ASID changes, so no need to
 650        flush these entries again.  */
 651     if (tlb->G == 0 && tlb->ASID != ASID) {
 652         return;
 653     }
 654
 655     if (use_extra && env->tlb->tlb_in_use < MIPS_TLB_MAX) {
 656         /* For tlbwr, we can shadow the discarded entry into
 657            a new (fake) TLB entry, as long as the guest can not
 658            tell that it's there.  */
 659         env->tlb->mmu.r4k.tlb[env->tlb->tlb_in_use] = *tlb;
 660         env->tlb->tlb_in_use++;
 661         return;
 662     }
 663
 664     /* 1k pages are not supported. */
 665     mask = tlb->PageMask | ~(TARGET_PAGE_MASK << 1);
 666     if (tlb->V0) {
 667         addr = tlb->VPN & ~mask;
 668 #if defined(TARGET_MIPS64)
 669         if (addr >= (0xFFFFFFFF80000000ULL & env->SEGMask)) {
 670             addr |= 0x3FFFFF0000000000ULL;
 671         }
 672 #endif
 673         end = addr | (mask >> 1);
 674         while (addr < end) {
 675             tlb_flush_page (env, addr);
 676             addr += TARGET_PAGE_SIZE;
 677         }
 678     }
 679     if (tlb->V1) {
 680         addr = (tlb->VPN & ~mask) | ((mask >> 1) + 1);
 681 #if defined(TARGET_MIPS64)
 682         if (addr >= (0xFFFFFFFF80000000ULL & env->SEGMask)) {
 683             addr |= 0x3FFFFF0000000000ULL;
 684         }
 685 #endif
 686         end = addr | mask;
 687         while (addr - 1 < end) {
 688             tlb_flush_page (env, addr);
 689             addr += TARGET_PAGE_SIZE;
 690         }
 691     }
 692 }
 693 #endif