linux/arch/mips/kernel/mips-r2-to-r6-emul.c
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   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) 2014 Imagination Technologies Ltd.
   7 * Author: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
   8 * Author: Markos Chandras <markos.chandras@imgtec.com>
   9 *
  10 *      MIPS R2 user space instruction emulator for MIPS R6
  11 *
  12 */
  13#include <linux/bug.h>
  14#include <linux/compiler.h>
  15#include <linux/debugfs.h>
  16#include <linux/init.h>
  17#include <linux/kernel.h>
  18#include <linux/module.h>
  19#include <linux/ptrace.h>
  20#include <linux/seq_file.h>
  21
  22#include <asm/asm.h>
  23#include <asm/branch.h>
  24#include <asm/break.h>
  25#include <asm/debug.h>
  26#include <asm/fpu.h>
  27#include <asm/fpu_emulator.h>
  28#include <asm/inst.h>
  29#include <asm/mips-r2-to-r6-emul.h>
  30#include <asm/local.h>
  31#include <asm/ptrace.h>
  32#include <asm/uaccess.h>
  33
  34#ifdef CONFIG_64BIT
  35#define ADDIU   "daddiu "
  36#define INS     "dins "
  37#define EXT     "dext "
  38#else
  39#define ADDIU   "addiu "
  40#define INS     "ins "
  41#define EXT     "ext "
  42#endif /* CONFIG_64BIT */
  43
  44#define SB      "sb "
  45#define LB      "lb "
  46#define LL      "ll "
  47#define SC      "sc "
  48
  49DEFINE_PER_CPU(struct mips_r2_emulator_stats, mipsr2emustats);
  50DEFINE_PER_CPU(struct mips_r2_emulator_stats, mipsr2bdemustats);
  51DEFINE_PER_CPU(struct mips_r2br_emulator_stats, mipsr2bremustats);
  52
  53extern const unsigned int fpucondbit[8];
  54
  55#define MIPS_R2_EMUL_TOTAL_PASS 10
  56
  57int mipsr2_emulation = 0;
  58
  59static int __init mipsr2emu_enable(char *s)
  60{
  61        mipsr2_emulation = 1;
  62
  63        pr_info("MIPS R2-to-R6 Emulator Enabled!");
  64
  65        return 1;
  66}
  67__setup("mipsr2emu", mipsr2emu_enable);
  68
  69/**
  70 * mipsr6_emul - Emulate some frequent R2/R5/R6 instructions in delay slot
  71 * for performance instead of the traditional way of using a stack trampoline
  72 * which is rather slow.
  73 * @regs: Process register set
  74 * @ir: Instruction
  75 */
  76static inline int mipsr6_emul(struct pt_regs *regs, u32 ir)
  77{
  78        switch (MIPSInst_OPCODE(ir)) {
  79        case addiu_op:
  80                if (MIPSInst_RT(ir))
  81                        regs->regs[MIPSInst_RT(ir)] =
  82                                (s32)regs->regs[MIPSInst_RS(ir)] +
  83                                (s32)MIPSInst_SIMM(ir);
  84                return 0;
  85        case daddiu_op:
  86                if (config_enabled(CONFIG_32BIT))
  87                        break;
  88
  89                if (MIPSInst_RT(ir))
  90                        regs->regs[MIPSInst_RT(ir)] =
  91                                (s64)regs->regs[MIPSInst_RS(ir)] +
  92                                (s64)MIPSInst_SIMM(ir);
  93                return 0;
  94        case lwc1_op:
  95        case swc1_op:
  96        case cop1_op:
  97        case cop1x_op:
  98                /* FPU instructions in delay slot */
  99                return -SIGFPE;
 100        case spec_op:
 101                switch (MIPSInst_FUNC(ir)) {
 102                case or_op:
 103                        if (MIPSInst_RD(ir))
 104                                regs->regs[MIPSInst_RD(ir)] =
 105                                        regs->regs[MIPSInst_RS(ir)] |
 106                                        regs->regs[MIPSInst_RT(ir)];
 107                        return 0;
 108                case sll_op:
 109                        if (MIPSInst_RS(ir))
 110                                break;
 111
 112                        if (MIPSInst_RD(ir))
 113                                regs->regs[MIPSInst_RD(ir)] =
 114                                        (s32)(((u32)regs->regs[MIPSInst_RT(ir)]) <<
 115                                                MIPSInst_FD(ir));
 116                        return 0;
 117                case srl_op:
 118                        if (MIPSInst_RS(ir))
 119                                break;
 120
 121                        if (MIPSInst_RD(ir))
 122                                regs->regs[MIPSInst_RD(ir)] =
 123                                        (s32)(((u32)regs->regs[MIPSInst_RT(ir)]) >>
 124                                                MIPSInst_FD(ir));
 125                        return 0;
 126                case addu_op:
 127                        if (MIPSInst_FD(ir))
 128                                break;
 129
 130                        if (MIPSInst_RD(ir))
 131                                regs->regs[MIPSInst_RD(ir)] =
 132                                        (s32)((u32)regs->regs[MIPSInst_RS(ir)] +
 133                                              (u32)regs->regs[MIPSInst_RT(ir)]);
 134                        return 0;
 135                case subu_op:
 136                        if (MIPSInst_FD(ir))
 137                                break;
 138
 139                        if (MIPSInst_RD(ir))
 140                                regs->regs[MIPSInst_RD(ir)] =
 141                                        (s32)((u32)regs->regs[MIPSInst_RS(ir)] -
 142                                              (u32)regs->regs[MIPSInst_RT(ir)]);
 143                        return 0;
 144                case dsll_op:
 145                        if (config_enabled(CONFIG_32BIT) || MIPSInst_RS(ir))
 146                                break;
 147
 148                        if (MIPSInst_RD(ir))
 149                                regs->regs[MIPSInst_RD(ir)] =
 150                                        (s64)(((u64)regs->regs[MIPSInst_RT(ir)]) <<
 151                                                MIPSInst_FD(ir));
 152                        return 0;
 153                case dsrl_op:
 154                        if (config_enabled(CONFIG_32BIT) || MIPSInst_RS(ir))
 155                                break;
 156
 157                        if (MIPSInst_RD(ir))
 158                                regs->regs[MIPSInst_RD(ir)] =
 159                                        (s64)(((u64)regs->regs[MIPSInst_RT(ir)]) >>
 160                                                MIPSInst_FD(ir));
 161                        return 0;
 162                case daddu_op:
 163                        if (config_enabled(CONFIG_32BIT) || MIPSInst_FD(ir))
 164                                break;
 165
 166                        if (MIPSInst_RD(ir))
 167                                regs->regs[MIPSInst_RD(ir)] =
 168                                        (u64)regs->regs[MIPSInst_RS(ir)] +
 169                                        (u64)regs->regs[MIPSInst_RT(ir)];
 170                        return 0;
 171                case dsubu_op:
 172                        if (config_enabled(CONFIG_32BIT) || MIPSInst_FD(ir))
 173                                break;
 174
 175                        if (MIPSInst_RD(ir))
 176                                regs->regs[MIPSInst_RD(ir)] =
 177                                        (s64)((u64)regs->regs[MIPSInst_RS(ir)] -
 178                                              (u64)regs->regs[MIPSInst_RT(ir)]);
 179                        return 0;
 180                }
 181                break;
 182        default:
 183                pr_debug("No fastpath BD emulation for instruction 0x%08x (op: %02x)\n",
 184                         ir, MIPSInst_OPCODE(ir));
 185        }
 186
 187        return SIGILL;
 188}
 189
 190/**
 191 * movf_func - Emulate a MOVF instruction
 192 * @regs: Process register set
 193 * @ir: Instruction
 194 *
 195 * Returns 0 since it always succeeds.
 196 */
 197static int movf_func(struct pt_regs *regs, u32 ir)
 198{
 199        u32 csr;
 200        u32 cond;
 201
 202        csr = current->thread.fpu.fcr31;
 203        cond = fpucondbit[MIPSInst_RT(ir) >> 2];
 204
 205        if (((csr & cond) == 0) && MIPSInst_RD(ir))
 206                regs->regs[MIPSInst_RD(ir)] = regs->regs[MIPSInst_RS(ir)];
 207
 208        MIPS_R2_STATS(movs);
 209
 210        return 0;
 211}
 212
 213/**
 214 * movt_func - Emulate a MOVT instruction
 215 * @regs: Process register set
 216 * @ir: Instruction
 217 *
 218 * Returns 0 since it always succeeds.
 219 */
 220static int movt_func(struct pt_regs *regs, u32 ir)
 221{
 222        u32 csr;
 223        u32 cond;
 224
 225        csr = current->thread.fpu.fcr31;
 226        cond = fpucondbit[MIPSInst_RT(ir) >> 2];
 227
 228        if (((csr & cond) != 0) && MIPSInst_RD(ir))
 229                regs->regs[MIPSInst_RD(ir)] = regs->regs[MIPSInst_RS(ir)];
 230
 231        MIPS_R2_STATS(movs);
 232
 233        return 0;
 234}
 235
 236/**
 237 * jr_func - Emulate a JR instruction.
 238 * @pt_regs: Process register set
 239 * @ir: Instruction
 240 *
 241 * Returns SIGILL if JR was in delay slot, SIGEMT if we
 242 * can't compute the EPC, SIGSEGV if we can't access the
 243 * userland instruction or 0 on success.
 244 */
 245static int jr_func(struct pt_regs *regs, u32 ir)
 246{
 247        int err;
 248        unsigned long cepc, epc, nepc;
 249        u32 nir;
 250
 251        if (delay_slot(regs))
 252                return SIGILL;
 253
 254        /* EPC after the RI/JR instruction */
 255        nepc = regs->cp0_epc;
 256        /* Roll back to the reserved R2 JR instruction */
 257        regs->cp0_epc -= 4;
 258        epc = regs->cp0_epc;
 259        err = __compute_return_epc(regs);
 260
 261        if (err < 0)
 262                return SIGEMT;
 263
 264
 265        /* Computed EPC */
 266        cepc = regs->cp0_epc;
 267
 268        /* Get DS instruction */
 269        err = __get_user(nir, (u32 __user *)nepc);
 270        if (err)
 271                return SIGSEGV;
 272
 273        MIPS_R2BR_STATS(jrs);
 274
 275        /* If nir == 0(NOP), then nothing else to do */
 276        if (nir) {
 277                /*
 278                 * Negative err means FPU instruction in BD-slot,
 279                 * Zero err means 'BD-slot emulation done'
 280                 * For anything else we go back to trampoline emulation.
 281                 */
 282                err = mipsr6_emul(regs, nir);
 283                if (err > 0) {
 284                        regs->cp0_epc = nepc;
 285                        err = mips_dsemul(regs, nir, cepc);
 286                        if (err == SIGILL)
 287                                err = SIGEMT;
 288                        MIPS_R2_STATS(dsemul);
 289                }
 290        }
 291
 292        return err;
 293}
 294
 295/**
 296 * movz_func - Emulate a MOVZ instruction
 297 * @regs: Process register set
 298 * @ir: Instruction
 299 *
 300 * Returns 0 since it always succeeds.
 301 */
 302static int movz_func(struct pt_regs *regs, u32 ir)
 303{
 304        if (((regs->regs[MIPSInst_RT(ir)]) == 0) && MIPSInst_RD(ir))
 305                regs->regs[MIPSInst_RD(ir)] = regs->regs[MIPSInst_RS(ir)];
 306        MIPS_R2_STATS(movs);
 307
 308        return 0;
 309}
 310
 311/**
 312 * movn_func - Emulate a MOVZ instruction
 313 * @regs: Process register set
 314 * @ir: Instruction
 315 *
 316 * Returns 0 since it always succeeds.
 317 */
 318static int movn_func(struct pt_regs *regs, u32 ir)
 319{
 320        if (((regs->regs[MIPSInst_RT(ir)]) != 0) && MIPSInst_RD(ir))
 321                regs->regs[MIPSInst_RD(ir)] = regs->regs[MIPSInst_RS(ir)];
 322        MIPS_R2_STATS(movs);
 323
 324        return 0;
 325}
 326
 327/**
 328 * mfhi_func - Emulate a MFHI instruction
 329 * @regs: Process register set
 330 * @ir: Instruction
 331 *
 332 * Returns 0 since it always succeeds.
 333 */
 334static int mfhi_func(struct pt_regs *regs, u32 ir)
 335{
 336        if (MIPSInst_RD(ir))
 337                regs->regs[MIPSInst_RD(ir)] = regs->hi;
 338
 339        MIPS_R2_STATS(hilo);
 340
 341        return 0;
 342}
 343
 344/**
 345 * mthi_func - Emulate a MTHI instruction
 346 * @regs: Process register set
 347 * @ir: Instruction
 348 *
 349 * Returns 0 since it always succeeds.
 350 */
 351static int mthi_func(struct pt_regs *regs, u32 ir)
 352{
 353        regs->hi = regs->regs[MIPSInst_RS(ir)];
 354
 355        MIPS_R2_STATS(hilo);
 356
 357        return 0;
 358}
 359
 360/**
 361 * mflo_func - Emulate a MFLO instruction
 362 * @regs: Process register set
 363 * @ir: Instruction
 364 *
 365 * Returns 0 since it always succeeds.
 366 */
 367static int mflo_func(struct pt_regs *regs, u32 ir)
 368{
 369        if (MIPSInst_RD(ir))
 370                regs->regs[MIPSInst_RD(ir)] = regs->lo;
 371
 372        MIPS_R2_STATS(hilo);
 373
 374        return 0;
 375}
 376
 377/**
 378 * mtlo_func - Emulate a MTLO instruction
 379 * @regs: Process register set
 380 * @ir: Instruction
 381 *
 382 * Returns 0 since it always succeeds.
 383 */
 384static int mtlo_func(struct pt_regs *regs, u32 ir)
 385{
 386        regs->lo = regs->regs[MIPSInst_RS(ir)];
 387
 388        MIPS_R2_STATS(hilo);
 389
 390        return 0;
 391}
 392
 393/**
 394 * mult_func - Emulate a MULT instruction
 395 * @regs: Process register set
 396 * @ir: Instruction
 397 *
 398 * Returns 0 since it always succeeds.
 399 */
 400static int mult_func(struct pt_regs *regs, u32 ir)
 401{
 402        s64 res;
 403        s32 rt, rs;
 404
 405        rt = regs->regs[MIPSInst_RT(ir)];
 406        rs = regs->regs[MIPSInst_RS(ir)];
 407        res = (s64)rt * (s64)rs;
 408
 409        rs = res;
 410        regs->lo = (s64)rs;
 411        rt = res >> 32;
 412        res = (s64)rt;
 413        regs->hi = res;
 414
 415        MIPS_R2_STATS(muls);
 416
 417        return 0;
 418}
 419
 420/**
 421 * multu_func - Emulate a MULTU instruction
 422 * @regs: Process register set
 423 * @ir: Instruction
 424 *
 425 * Returns 0 since it always succeeds.
 426 */
 427static int multu_func(struct pt_regs *regs, u32 ir)
 428{
 429        u64 res;
 430        u32 rt, rs;
 431
 432        rt = regs->regs[MIPSInst_RT(ir)];
 433        rs = regs->regs[MIPSInst_RS(ir)];
 434        res = (u64)rt * (u64)rs;
 435        rt = res;
 436        regs->lo = (s64)rt;
 437        regs->hi = (s64)(res >> 32);
 438
 439        MIPS_R2_STATS(muls);
 440
 441        return 0;
 442}
 443
 444/**
 445 * div_func - Emulate a DIV instruction
 446 * @regs: Process register set
 447 * @ir: Instruction
 448 *
 449 * Returns 0 since it always succeeds.
 450 */
 451static int div_func(struct pt_regs *regs, u32 ir)
 452{
 453        s32 rt, rs;
 454
 455        rt = regs->regs[MIPSInst_RT(ir)];
 456        rs = regs->regs[MIPSInst_RS(ir)];
 457
 458        regs->lo = (s64)(rs / rt);
 459        regs->hi = (s64)(rs % rt);
 460
 461        MIPS_R2_STATS(divs);
 462
 463        return 0;
 464}
 465
 466/**
 467 * divu_func - Emulate a DIVU instruction
 468 * @regs: Process register set
 469 * @ir: Instruction
 470 *
 471 * Returns 0 since it always succeeds.
 472 */
 473static int divu_func(struct pt_regs *regs, u32 ir)
 474{
 475        u32 rt, rs;
 476
 477        rt = regs->regs[MIPSInst_RT(ir)];
 478        rs = regs->regs[MIPSInst_RS(ir)];
 479
 480        regs->lo = (s64)(rs / rt);
 481        regs->hi = (s64)(rs % rt);
 482
 483        MIPS_R2_STATS(divs);
 484
 485        return 0;
 486}
 487
 488/**
 489 * dmult_func - Emulate a DMULT instruction
 490 * @regs: Process register set
 491 * @ir: Instruction
 492 *
 493 * Returns 0 on success or SIGILL for 32-bit kernels.
 494 */
 495static int dmult_func(struct pt_regs *regs, u32 ir)
 496{
 497        s64 res;
 498        s64 rt, rs;
 499
 500        if (config_enabled(CONFIG_32BIT))
 501                return SIGILL;
 502
 503        rt = regs->regs[MIPSInst_RT(ir)];
 504        rs = regs->regs[MIPSInst_RS(ir)];
 505        res = rt * rs;
 506
 507        regs->lo = res;
 508        __asm__ __volatile__(
 509                "dmuh %0, %1, %2\t\n"
 510                : "=r"(res)
 511                : "r"(rt), "r"(rs));
 512
 513        regs->hi = res;
 514
 515        MIPS_R2_STATS(muls);
 516
 517        return 0;
 518}
 519
 520/**
 521 * dmultu_func - Emulate a DMULTU instruction
 522 * @regs: Process register set
 523 * @ir: Instruction
 524 *
 525 * Returns 0 on success or SIGILL for 32-bit kernels.
 526 */
 527static int dmultu_func(struct pt_regs *regs, u32 ir)
 528{
 529        u64 res;
 530        u64 rt, rs;
 531
 532        if (config_enabled(CONFIG_32BIT))
 533                return SIGILL;
 534
 535        rt = regs->regs[MIPSInst_RT(ir)];
 536        rs = regs->regs[MIPSInst_RS(ir)];
 537        res = rt * rs;
 538
 539        regs->lo = res;
 540        __asm__ __volatile__(
 541                "dmuhu %0, %1, %2\t\n"
 542                : "=r"(res)
 543                : "r"(rt), "r"(rs));
 544
 545        regs->hi = res;
 546
 547        MIPS_R2_STATS(muls);
 548
 549        return 0;
 550}
 551
 552/**
 553 * ddiv_func - Emulate a DDIV instruction
 554 * @regs: Process register set
 555 * @ir: Instruction
 556 *
 557 * Returns 0 on success or SIGILL for 32-bit kernels.
 558 */
 559static int ddiv_func(struct pt_regs *regs, u32 ir)
 560{
 561        s64 rt, rs;
 562
 563        if (config_enabled(CONFIG_32BIT))
 564                return SIGILL;
 565
 566        rt = regs->regs[MIPSInst_RT(ir)];
 567        rs = regs->regs[MIPSInst_RS(ir)];
 568
 569        regs->lo = rs / rt;
 570        regs->hi = rs % rt;
 571
 572        MIPS_R2_STATS(divs);
 573
 574        return 0;
 575}
 576
 577/**
 578 * ddivu_func - Emulate a DDIVU instruction
 579 * @regs: Process register set
 580 * @ir: Instruction
 581 *
 582 * Returns 0 on success or SIGILL for 32-bit kernels.
 583 */
 584static int ddivu_func(struct pt_regs *regs, u32 ir)
 585{
 586        u64 rt, rs;
 587
 588        if (config_enabled(CONFIG_32BIT))
 589                return SIGILL;
 590
 591        rt = regs->regs[MIPSInst_RT(ir)];
 592        rs = regs->regs[MIPSInst_RS(ir)];
 593
 594        regs->lo = rs / rt;
 595        regs->hi = rs % rt;
 596
 597        MIPS_R2_STATS(divs);
 598
 599        return 0;
 600}
 601
 602/* R6 removed instructions for the SPECIAL opcode */
 603static struct r2_decoder_table spec_op_table[] = {
 604        { 0xfc1ff83f, 0x00000008, jr_func },
 605        { 0xfc00ffff, 0x00000018, mult_func },
 606        { 0xfc00ffff, 0x00000019, multu_func },
 607        { 0xfc00ffff, 0x0000001c, dmult_func },
 608        { 0xfc00ffff, 0x0000001d, dmultu_func },
 609        { 0xffff07ff, 0x00000010, mfhi_func },
 610        { 0xfc1fffff, 0x00000011, mthi_func },
 611        { 0xffff07ff, 0x00000012, mflo_func },
 612        { 0xfc1fffff, 0x00000013, mtlo_func },
 613        { 0xfc0307ff, 0x00000001, movf_func },
 614        { 0xfc0307ff, 0x00010001, movt_func },
 615        { 0xfc0007ff, 0x0000000a, movz_func },
 616        { 0xfc0007ff, 0x0000000b, movn_func },
 617        { 0xfc00ffff, 0x0000001a, div_func },
 618        { 0xfc00ffff, 0x0000001b, divu_func },
 619        { 0xfc00ffff, 0x0000001e, ddiv_func },
 620        { 0xfc00ffff, 0x0000001f, ddivu_func },
 621        {}
 622};
 623
 624/**
 625 * madd_func - Emulate a MADD instruction
 626 * @regs: Process register set
 627 * @ir: Instruction
 628 *
 629 * Returns 0 since it always succeeds.
 630 */
 631static int madd_func(struct pt_regs *regs, u32 ir)
 632{
 633        s64 res;
 634        s32 rt, rs;
 635
 636        rt = regs->regs[MIPSInst_RT(ir)];
 637        rs = regs->regs[MIPSInst_RS(ir)];
 638        res = (s64)rt * (s64)rs;
 639        rt = regs->hi;
 640        rs = regs->lo;
 641        res += ((((s64)rt) << 32) | (u32)rs);
 642
 643        rt = res;
 644        regs->lo = (s64)rt;
 645        rs = res >> 32;
 646        regs->hi = (s64)rs;
 647
 648        MIPS_R2_STATS(dsps);
 649
 650        return 0;
 651}
 652
 653/**
 654 * maddu_func - Emulate a MADDU instruction
 655 * @regs: Process register set
 656 * @ir: Instruction
 657 *
 658 * Returns 0 since it always succeeds.
 659 */
 660static int maddu_func(struct pt_regs *regs, u32 ir)
 661{
 662        u64 res;
 663        u32 rt, rs;
 664
 665        rt = regs->regs[MIPSInst_RT(ir)];
 666        rs = regs->regs[MIPSInst_RS(ir)];
 667        res = (u64)rt * (u64)rs;
 668        rt = regs->hi;
 669        rs = regs->lo;
 670        res += ((((s64)rt) << 32) | (u32)rs);
 671
 672        rt = res;
 673        regs->lo = (s64)rt;
 674        rs = res >> 32;
 675        regs->hi = (s64)rs;
 676
 677        MIPS_R2_STATS(dsps);
 678
 679        return 0;
 680}
 681
 682/**
 683 * msub_func - Emulate a MSUB instruction
 684 * @regs: Process register set
 685 * @ir: Instruction
 686 *
 687 * Returns 0 since it always succeeds.
 688 */
 689static int msub_func(struct pt_regs *regs, u32 ir)
 690{
 691        s64 res;
 692        s32 rt, rs;
 693
 694        rt = regs->regs[MIPSInst_RT(ir)];
 695        rs = regs->regs[MIPSInst_RS(ir)];
 696        res = (s64)rt * (s64)rs;
 697        rt = regs->hi;
 698        rs = regs->lo;
 699        res = ((((s64)rt) << 32) | (u32)rs) - res;
 700
 701        rt = res;
 702        regs->lo = (s64)rt;
 703        rs = res >> 32;
 704        regs->hi = (s64)rs;
 705
 706        MIPS_R2_STATS(dsps);
 707
 708        return 0;
 709}
 710
 711/**
 712 * msubu_func - Emulate a MSUBU instruction
 713 * @regs: Process register set
 714 * @ir: Instruction
 715 *
 716 * Returns 0 since it always succeeds.
 717 */
 718static int msubu_func(struct pt_regs *regs, u32 ir)
 719{
 720        u64 res;
 721        u32 rt, rs;
 722
 723        rt = regs->regs[MIPSInst_RT(ir)];
 724        rs = regs->regs[MIPSInst_RS(ir)];
 725        res = (u64)rt * (u64)rs;
 726        rt = regs->hi;
 727        rs = regs->lo;
 728        res = ((((s64)rt) << 32) | (u32)rs) - res;
 729
 730        rt = res;
 731        regs->lo = (s64)rt;
 732        rs = res >> 32;
 733        regs->hi = (s64)rs;
 734
 735        MIPS_R2_STATS(dsps);
 736
 737        return 0;
 738}
 739
 740/**
 741 * mul_func - Emulate a MUL instruction
 742 * @regs: Process register set
 743 * @ir: Instruction
 744 *
 745 * Returns 0 since it always succeeds.
 746 */
 747static int mul_func(struct pt_regs *regs, u32 ir)
 748{
 749        s64 res;
 750        s32 rt, rs;
 751
 752        if (!MIPSInst_RD(ir))
 753                return 0;
 754        rt = regs->regs[MIPSInst_RT(ir)];
 755        rs = regs->regs[MIPSInst_RS(ir)];
 756        res = (s64)rt * (s64)rs;
 757
 758        rs = res;
 759        regs->regs[MIPSInst_RD(ir)] = (s64)rs;
 760
 761        MIPS_R2_STATS(muls);
 762
 763        return 0;
 764}
 765
 766/**
 767 * clz_func - Emulate a CLZ instruction
 768 * @regs: Process register set
 769 * @ir: Instruction
 770 *
 771 * Returns 0 since it always succeeds.
 772 */
 773static int clz_func(struct pt_regs *regs, u32 ir)
 774{
 775        u32 res;
 776        u32 rs;
 777
 778        if (!MIPSInst_RD(ir))
 779                return 0;
 780
 781        rs = regs->regs[MIPSInst_RS(ir)];
 782        __asm__ __volatile__("clz %0, %1" : "=r"(res) : "r"(rs));
 783        regs->regs[MIPSInst_RD(ir)] = res;
 784
 785        MIPS_R2_STATS(bops);
 786
 787        return 0;
 788}
 789
 790/**
 791 * clo_func - Emulate a CLO instruction
 792 * @regs: Process register set
 793 * @ir: Instruction
 794 *
 795 * Returns 0 since it always succeeds.
 796 */
 797
 798static int clo_func(struct pt_regs *regs, u32 ir)
 799{
 800        u32 res;
 801        u32 rs;
 802
 803        if (!MIPSInst_RD(ir))
 804                return 0;
 805
 806        rs = regs->regs[MIPSInst_RS(ir)];
 807        __asm__ __volatile__("clo %0, %1" : "=r"(res) : "r"(rs));
 808        regs->regs[MIPSInst_RD(ir)] = res;
 809
 810        MIPS_R2_STATS(bops);
 811
 812        return 0;
 813}
 814
 815/**
 816 * dclz_func - Emulate a DCLZ instruction
 817 * @regs: Process register set
 818 * @ir: Instruction
 819 *
 820 * Returns 0 since it always succeeds.
 821 */
 822static int dclz_func(struct pt_regs *regs, u32 ir)
 823{
 824        u64 res;
 825        u64 rs;
 826
 827        if (config_enabled(CONFIG_32BIT))
 828                return SIGILL;
 829
 830        if (!MIPSInst_RD(ir))
 831                return 0;
 832
 833        rs = regs->regs[MIPSInst_RS(ir)];
 834        __asm__ __volatile__("dclz %0, %1" : "=r"(res) : "r"(rs));
 835        regs->regs[MIPSInst_RD(ir)] = res;
 836
 837        MIPS_R2_STATS(bops);
 838
 839        return 0;
 840}
 841
 842/**
 843 * dclo_func - Emulate a DCLO instruction
 844 * @regs: Process register set
 845 * @ir: Instruction
 846 *
 847 * Returns 0 since it always succeeds.
 848 */
 849static int dclo_func(struct pt_regs *regs, u32 ir)
 850{
 851        u64 res;
 852        u64 rs;
 853
 854        if (config_enabled(CONFIG_32BIT))
 855                return SIGILL;
 856
 857        if (!MIPSInst_RD(ir))
 858                return 0;
 859
 860        rs = regs->regs[MIPSInst_RS(ir)];
 861        __asm__ __volatile__("dclo %0, %1" : "=r"(res) : "r"(rs));
 862        regs->regs[MIPSInst_RD(ir)] = res;
 863
 864        MIPS_R2_STATS(bops);
 865
 866        return 0;
 867}
 868
 869/* R6 removed instructions for the SPECIAL2 opcode */
 870static struct r2_decoder_table spec2_op_table[] = {
 871        { 0xfc00ffff, 0x70000000, madd_func },
 872        { 0xfc00ffff, 0x70000001, maddu_func },
 873        { 0xfc0007ff, 0x70000002, mul_func },
 874        { 0xfc00ffff, 0x70000004, msub_func },
 875        { 0xfc00ffff, 0x70000005, msubu_func },
 876        { 0xfc0007ff, 0x70000020, clz_func },
 877        { 0xfc0007ff, 0x70000021, clo_func },
 878        { 0xfc0007ff, 0x70000024, dclz_func },
 879        { 0xfc0007ff, 0x70000025, dclo_func },
 880        { }
 881};
 882
 883static inline int mipsr2_find_op_func(struct pt_regs *regs, u32 inst,
 884                                      struct r2_decoder_table *table)
 885{
 886        struct r2_decoder_table *p;
 887        int err;
 888
 889        for (p = table; p->func; p++) {
 890                if ((inst & p->mask) == p->code) {
 891                        err = (p->func)(regs, inst);
 892                        return err;
 893                }
 894        }
 895        return SIGILL;
 896}
 897
 898/**
 899 * mipsr2_decoder: Decode and emulate a MIPS R2 instruction
 900 * @regs: Process register set
 901 * @inst: Instruction to decode and emulate
 902 * @fcr31: Floating Point Control and Status Register returned
 903 */
 904int mipsr2_decoder(struct pt_regs *regs, u32 inst, unsigned long *fcr31)
 905{
 906        int err = 0;
 907        unsigned long vaddr;
 908        u32 nir;
 909        unsigned long cpc, epc, nepc, r31, res, rs, rt;
 910
 911        void __user *fault_addr = NULL;
 912        int pass = 0;
 913
 914repeat:
 915        r31 = regs->regs[31];
 916        epc = regs->cp0_epc;
 917        err = compute_return_epc(regs);
 918        if (err < 0) {
 919                BUG();
 920                return SIGEMT;
 921        }
 922        pr_debug("Emulating the 0x%08x R2 instruction @ 0x%08lx (pass=%d))\n",
 923                 inst, epc, pass);
 924
 925        switch (MIPSInst_OPCODE(inst)) {
 926        case spec_op:
 927                err = mipsr2_find_op_func(regs, inst, spec_op_table);
 928                if (err < 0) {
 929                        /* FPU instruction under JR */
 930                        regs->cp0_cause |= CAUSEF_BD;
 931                        goto fpu_emul;
 932                }
 933                break;
 934        case spec2_op:
 935                err = mipsr2_find_op_func(regs, inst, spec2_op_table);
 936                break;
 937        case bcond_op:
 938                rt = MIPSInst_RT(inst);
 939                rs = MIPSInst_RS(inst);
 940                switch (rt) {
 941                case tgei_op:
 942                        if ((long)regs->regs[rs] >= MIPSInst_SIMM(inst))
 943                                do_trap_or_bp(regs, 0, "TGEI");
 944
 945                        MIPS_R2_STATS(traps);
 946
 947                        break;
 948                case tgeiu_op:
 949                        if (regs->regs[rs] >= MIPSInst_UIMM(inst))
 950                                do_trap_or_bp(regs, 0, "TGEIU");
 951
 952                        MIPS_R2_STATS(traps);
 953
 954                        break;
 955                case tlti_op:
 956                        if ((long)regs->regs[rs] < MIPSInst_SIMM(inst))
 957                                do_trap_or_bp(regs, 0, "TLTI");
 958
 959                        MIPS_R2_STATS(traps);
 960
 961                        break;
 962                case tltiu_op:
 963                        if (regs->regs[rs] < MIPSInst_UIMM(inst))
 964                                do_trap_or_bp(regs, 0, "TLTIU");
 965
 966                        MIPS_R2_STATS(traps);
 967
 968                        break;
 969                case teqi_op:
 970                        if (regs->regs[rs] == MIPSInst_SIMM(inst))
 971                                do_trap_or_bp(regs, 0, "TEQI");
 972
 973                        MIPS_R2_STATS(traps);
 974
 975                        break;
 976                case tnei_op:
 977                        if (regs->regs[rs] != MIPSInst_SIMM(inst))
 978                                do_trap_or_bp(regs, 0, "TNEI");
 979
 980                        MIPS_R2_STATS(traps);
 981
 982                        break;
 983                case bltzl_op:
 984                case bgezl_op:
 985                case bltzall_op:
 986                case bgezall_op:
 987                        if (delay_slot(regs)) {
 988                                err = SIGILL;
 989                                break;
 990                        }
 991                        regs->regs[31] = r31;
 992                        regs->cp0_epc = epc;
 993                        err = __compute_return_epc(regs);
 994                        if (err < 0)
 995                                return SIGEMT;
 996                        if (err != BRANCH_LIKELY_TAKEN)
 997                                break;
 998                        cpc = regs->cp0_epc;
 999                        nepc = epc + 4;
1000                        err = __get_user(nir, (u32 __user *)nepc);
1001                        if (err) {
1002                                err = SIGSEGV;
1003                                break;
1004                        }
1005                        /*
1006                         * This will probably be optimized away when
1007                         * CONFIG_DEBUG_FS is not enabled
1008                         */
1009                        switch (rt) {
1010                        case bltzl_op:
1011                                MIPS_R2BR_STATS(bltzl);
1012                                break;
1013                        case bgezl_op:
1014                                MIPS_R2BR_STATS(bgezl);
1015                                break;
1016                        case bltzall_op:
1017                                MIPS_R2BR_STATS(bltzall);
1018                                break;
1019                        case bgezall_op:
1020                                MIPS_R2BR_STATS(bgezall);
1021                                break;
1022                        }
1023
1024                        switch (MIPSInst_OPCODE(nir)) {
1025                        case cop1_op:
1026                        case cop1x_op:
1027                        case lwc1_op:
1028                        case swc1_op:
1029                                regs->cp0_cause |= CAUSEF_BD;
1030                                goto fpu_emul;
1031                        }
1032                        if (nir) {
1033                                err = mipsr6_emul(regs, nir);
1034                                if (err > 0) {
1035                                        err = mips_dsemul(regs, nir, cpc);
1036                                        if (err == SIGILL)
1037                                                err = SIGEMT;
1038                                        MIPS_R2_STATS(dsemul);
1039                                }
1040                        }
1041                        break;
1042                case bltzal_op:
1043                case bgezal_op:
1044                        if (delay_slot(regs)) {
1045                                err = SIGILL;
1046                                break;
1047                        }
1048                        regs->regs[31] = r31;
1049                        regs->cp0_epc = epc;
1050                        err = __compute_return_epc(regs);
1051                        if (err < 0)
1052                                return SIGEMT;
1053                        cpc = regs->cp0_epc;
1054                        nepc = epc + 4;
1055                        err = __get_user(nir, (u32 __user *)nepc);
1056                        if (err) {
1057                                err = SIGSEGV;
1058                                break;
1059                        }
1060                        /*
1061                         * This will probably be optimized away when
1062                         * CONFIG_DEBUG_FS is not enabled
1063                         */
1064                        switch (rt) {
1065                        case bltzal_op:
1066                                MIPS_R2BR_STATS(bltzal);
1067                                break;
1068                        case bgezal_op:
1069                                MIPS_R2BR_STATS(bgezal);
1070                                break;
1071                        }
1072
1073                        switch (MIPSInst_OPCODE(nir)) {
1074                        case cop1_op:
1075                        case cop1x_op:
1076                        case lwc1_op:
1077                        case swc1_op:
1078                                regs->cp0_cause |= CAUSEF_BD;
1079                                goto fpu_emul;
1080                        }
1081                        if (nir) {
1082                                err = mipsr6_emul(regs, nir);
1083                                if (err > 0) {
1084                                        err = mips_dsemul(regs, nir, cpc);
1085                                        if (err == SIGILL)
1086                                                err = SIGEMT;
1087                                        MIPS_R2_STATS(dsemul);
1088                                }
1089                        }
1090                        break;
1091                default:
1092                        regs->regs[31] = r31;
1093                        regs->cp0_epc = epc;
1094                        err = SIGILL;
1095                        break;
1096                }
1097                break;
1098
1099        case beql_op:
1100        case bnel_op:
1101        case blezl_op:
1102        case bgtzl_op:
1103                if (delay_slot(regs)) {
1104                        err = SIGILL;
1105                        break;
1106                }
1107                regs->regs[31] = r31;
1108                regs->cp0_epc = epc;
1109                err = __compute_return_epc(regs);
1110                if (err < 0)
1111                        return SIGEMT;
1112                if (err != BRANCH_LIKELY_TAKEN)
1113                        break;
1114                cpc = regs->cp0_epc;
1115                nepc = epc + 4;
1116                err = __get_user(nir, (u32 __user *)nepc);
1117                if (err) {
1118                        err = SIGSEGV;
1119                        break;
1120                }
1121                /*
1122                 * This will probably be optimized away when
1123                 * CONFIG_DEBUG_FS is not enabled
1124                 */
1125                switch (MIPSInst_OPCODE(inst)) {
1126                case beql_op:
1127                        MIPS_R2BR_STATS(beql);
1128                        break;
1129                case bnel_op:
1130                        MIPS_R2BR_STATS(bnel);
1131                        break;
1132                case blezl_op:
1133                        MIPS_R2BR_STATS(blezl);
1134                        break;
1135                case bgtzl_op:
1136                        MIPS_R2BR_STATS(bgtzl);
1137                        break;
1138                }
1139
1140                switch (MIPSInst_OPCODE(nir)) {
1141                case cop1_op:
1142                case cop1x_op:
1143                case lwc1_op:
1144                case swc1_op:
1145                        regs->cp0_cause |= CAUSEF_BD;
1146                        goto fpu_emul;
1147                }
1148                if (nir) {
1149                        err = mipsr6_emul(regs, nir);
1150                        if (err > 0) {
1151                                err = mips_dsemul(regs, nir, cpc);
1152                                if (err == SIGILL)
1153                                        err = SIGEMT;
1154                                MIPS_R2_STATS(dsemul);
1155                        }
1156                }
1157                break;
1158        case lwc1_op:
1159        case swc1_op:
1160        case cop1_op:
1161        case cop1x_op:
1162fpu_emul:
1163                regs->regs[31] = r31;
1164                regs->cp0_epc = epc;
1165                if (!used_math()) {     /* First time FPU user.  */
1166                        err = init_fpu();
1167                        set_used_math();
1168                }
1169                lose_fpu(1);    /* Save FPU state for the emulator. */
1170
1171                err = fpu_emulator_cop1Handler(regs, &current->thread.fpu, 0,
1172                                               &fault_addr);
1173                *fcr31 = current->thread.fpu.fcr31;
1174
1175                /*
1176                 * We can't allow the emulated instruction to leave any of
1177                 * the cause bits set in $fcr31.
1178                 */
1179                current->thread.fpu.fcr31 &= ~FPU_CSR_ALL_X;
1180
1181                /*
1182                 * this is a tricky issue - lose_fpu() uses LL/SC atomics
1183                 * if FPU is owned and effectively cancels user level LL/SC.
1184                 * So, it could be logical to don't restore FPU ownership here.
1185                 * But the sequence of multiple FPU instructions is much much
1186                 * more often than LL-FPU-SC and I prefer loop here until
1187                 * next scheduler cycle cancels FPU ownership
1188                 */
1189                own_fpu(1);     /* Restore FPU state. */
1190
1191                if (err)
1192                        current->thread.cp0_baduaddr = (unsigned long)fault_addr;
1193
1194                MIPS_R2_STATS(fpus);
1195
1196                break;
1197
1198        case lwl_op:
1199                rt = regs->regs[MIPSInst_RT(inst)];
1200                vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1201                if (!access_ok(VERIFY_READ, vaddr, 4)) {
1202                        current->thread.cp0_baduaddr = vaddr;
1203                        err = SIGSEGV;
1204                        break;
1205                }
1206                __asm__ __volatile__(
1207                        "       .set    push\n"
1208                        "       .set    reorder\n"
1209#ifdef CONFIG_CPU_LITTLE_ENDIAN
1210                        "1:"    LB      "%1, 0(%2)\n"
1211                                INS     "%0, %1, 24, 8\n"
1212                        "       andi    %1, %2, 0x3\n"
1213                        "       beq     $0, %1, 9f\n"
1214                                ADDIU   "%2, %2, -1\n"
1215                        "2:"    LB      "%1, 0(%2)\n"
1216                                INS     "%0, %1, 16, 8\n"
1217                        "       andi    %1, %2, 0x3\n"
1218                        "       beq     $0, %1, 9f\n"
1219                                ADDIU   "%2, %2, -1\n"
1220                        "3:"    LB      "%1, 0(%2)\n"
1221                                INS     "%0, %1, 8, 8\n"
1222                        "       andi    %1, %2, 0x3\n"
1223                        "       beq     $0, %1, 9f\n"
1224                                ADDIU   "%2, %2, -1\n"
1225                        "4:"    LB      "%1, 0(%2)\n"
1226                                INS     "%0, %1, 0, 8\n"
1227#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1228                        "1:"    LB      "%1, 0(%2)\n"
1229                                INS     "%0, %1, 24, 8\n"
1230                                ADDIU   "%2, %2, 1\n"
1231                        "       andi    %1, %2, 0x3\n"
1232                        "       beq     $0, %1, 9f\n"
1233                        "2:"    LB      "%1, 0(%2)\n"
1234                                INS     "%0, %1, 16, 8\n"
1235                                ADDIU   "%2, %2, 1\n"
1236                        "       andi    %1, %2, 0x3\n"
1237                        "       beq     $0, %1, 9f\n"
1238                        "3:"    LB      "%1, 0(%2)\n"
1239                                INS     "%0, %1, 8, 8\n"
1240                                ADDIU   "%2, %2, 1\n"
1241                        "       andi    %1, %2, 0x3\n"
1242                        "       beq     $0, %1, 9f\n"
1243                        "4:"    LB      "%1, 0(%2)\n"
1244                                INS     "%0, %1, 0, 8\n"
1245#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1246                        "9:     sll     %0, %0, 0\n"
1247                        "10:\n"
1248                        "       .insn\n"
1249                        "       .section        .fixup,\"ax\"\n"
1250                        "8:     li      %3,%4\n"
1251                        "       j       10b\n"
1252                        "       .previous\n"
1253                        "       .section        __ex_table,\"a\"\n"
1254                        "       .word   1b,8b\n"
1255                        "       .word   2b,8b\n"
1256                        "       .word   3b,8b\n"
1257                        "       .word   4b,8b\n"
1258                        "       .previous\n"
1259                        "       .set    pop\n"
1260                        : "+&r"(rt), "=&r"(rs),
1261                          "+&r"(vaddr), "+&r"(err)
1262                        : "i"(SIGSEGV));
1263
1264                if (MIPSInst_RT(inst) && !err)
1265                        regs->regs[MIPSInst_RT(inst)] = rt;
1266
1267                MIPS_R2_STATS(loads);
1268
1269                break;
1270
1271        case lwr_op:
1272                rt = regs->regs[MIPSInst_RT(inst)];
1273                vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1274                if (!access_ok(VERIFY_READ, vaddr, 4)) {
1275                        current->thread.cp0_baduaddr = vaddr;
1276                        err = SIGSEGV;
1277                        break;
1278                }
1279                __asm__ __volatile__(
1280                        "       .set    push\n"
1281                        "       .set    reorder\n"
1282#ifdef CONFIG_CPU_LITTLE_ENDIAN
1283                        "1:"    LB      "%1, 0(%2)\n"
1284                                INS     "%0, %1, 0, 8\n"
1285                                ADDIU   "%2, %2, 1\n"
1286                        "       andi    %1, %2, 0x3\n"
1287                        "       beq     $0, %1, 9f\n"
1288                        "2:"    LB      "%1, 0(%2)\n"
1289                                INS     "%0, %1, 8, 8\n"
1290                                ADDIU   "%2, %2, 1\n"
1291                        "       andi    %1, %2, 0x3\n"
1292                        "       beq     $0, %1, 9f\n"
1293                        "3:"    LB      "%1, 0(%2)\n"
1294                                INS     "%0, %1, 16, 8\n"
1295                                ADDIU   "%2, %2, 1\n"
1296                        "       andi    %1, %2, 0x3\n"
1297                        "       beq     $0, %1, 9f\n"
1298                        "4:"    LB      "%1, 0(%2)\n"
1299                                INS     "%0, %1, 24, 8\n"
1300                        "       sll     %0, %0, 0\n"
1301#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1302                        "1:"    LB      "%1, 0(%2)\n"
1303                                INS     "%0, %1, 0, 8\n"
1304                        "       andi    %1, %2, 0x3\n"
1305                        "       beq     $0, %1, 9f\n"
1306                                ADDIU   "%2, %2, -1\n"
1307                        "2:"    LB      "%1, 0(%2)\n"
1308                                INS     "%0, %1, 8, 8\n"
1309                        "       andi    %1, %2, 0x3\n"
1310                        "       beq     $0, %1, 9f\n"
1311                                ADDIU   "%2, %2, -1\n"
1312                        "3:"    LB      "%1, 0(%2)\n"
1313                                INS     "%0, %1, 16, 8\n"
1314                        "       andi    %1, %2, 0x3\n"
1315                        "       beq     $0, %1, 9f\n"
1316                                ADDIU   "%2, %2, -1\n"
1317                        "4:"    LB      "%1, 0(%2)\n"
1318                                INS     "%0, %1, 24, 8\n"
1319                        "       sll     %0, %0, 0\n"
1320#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1321                        "9:\n"
1322                        "10:\n"
1323                        "       .insn\n"
1324                        "       .section        .fixup,\"ax\"\n"
1325                        "8:     li      %3,%4\n"
1326                        "       j       10b\n"
1327                        "       .previous\n"
1328                        "       .section        __ex_table,\"a\"\n"
1329                        "       .word   1b,8b\n"
1330                        "       .word   2b,8b\n"
1331                        "       .word   3b,8b\n"
1332                        "       .word   4b,8b\n"
1333                        "       .previous\n"
1334                        "       .set    pop\n"
1335                        : "+&r"(rt), "=&r"(rs),
1336                          "+&r"(vaddr), "+&r"(err)
1337                        : "i"(SIGSEGV));
1338                if (MIPSInst_RT(inst) && !err)
1339                        regs->regs[MIPSInst_RT(inst)] = rt;
1340
1341                MIPS_R2_STATS(loads);
1342
1343                break;
1344
1345        case swl_op:
1346                rt = regs->regs[MIPSInst_RT(inst)];
1347                vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1348                if (!access_ok(VERIFY_WRITE, vaddr, 4)) {
1349                        current->thread.cp0_baduaddr = vaddr;
1350                        err = SIGSEGV;
1351                        break;
1352                }
1353                __asm__ __volatile__(
1354                        "       .set    push\n"
1355                        "       .set    reorder\n"
1356#ifdef CONFIG_CPU_LITTLE_ENDIAN
1357                                EXT     "%1, %0, 24, 8\n"
1358                        "1:"    SB      "%1, 0(%2)\n"
1359                        "       andi    %1, %2, 0x3\n"
1360                        "       beq     $0, %1, 9f\n"
1361                                ADDIU   "%2, %2, -1\n"
1362                                EXT     "%1, %0, 16, 8\n"
1363                        "2:"    SB      "%1, 0(%2)\n"
1364                        "       andi    %1, %2, 0x3\n"
1365                        "       beq     $0, %1, 9f\n"
1366                                ADDIU   "%2, %2, -1\n"
1367                                EXT     "%1, %0, 8, 8\n"
1368                        "3:"    SB      "%1, 0(%2)\n"
1369                        "       andi    %1, %2, 0x3\n"
1370                        "       beq     $0, %1, 9f\n"
1371                                ADDIU   "%2, %2, -1\n"
1372                                EXT     "%1, %0, 0, 8\n"
1373                        "4:"    SB      "%1, 0(%2)\n"
1374#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1375                                EXT     "%1, %0, 24, 8\n"
1376                        "1:"    SB      "%1, 0(%2)\n"
1377                                ADDIU   "%2, %2, 1\n"
1378                        "       andi    %1, %2, 0x3\n"
1379                        "       beq     $0, %1, 9f\n"
1380                                EXT     "%1, %0, 16, 8\n"
1381                        "2:"    SB      "%1, 0(%2)\n"
1382                                ADDIU   "%2, %2, 1\n"
1383                        "       andi    %1, %2, 0x3\n"
1384                        "       beq     $0, %1, 9f\n"
1385                                EXT     "%1, %0, 8, 8\n"
1386                        "3:"    SB      "%1, 0(%2)\n"
1387                                ADDIU   "%2, %2, 1\n"
1388                        "       andi    %1, %2, 0x3\n"
1389                        "       beq     $0, %1, 9f\n"
1390                                EXT     "%1, %0, 0, 8\n"
1391                        "4:"    SB      "%1, 0(%2)\n"
1392#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1393                        "9:\n"
1394                        "       .insn\n"
1395                        "       .section        .fixup,\"ax\"\n"
1396                        "8:     li      %3,%4\n"
1397                        "       j       9b\n"
1398                        "       .previous\n"
1399                        "       .section        __ex_table,\"a\"\n"
1400                        "       .word   1b,8b\n"
1401                        "       .word   2b,8b\n"
1402                        "       .word   3b,8b\n"
1403                        "       .word   4b,8b\n"
1404                        "       .previous\n"
1405                        "       .set    pop\n"
1406                        : "+&r"(rt), "=&r"(rs),
1407                          "+&r"(vaddr), "+&r"(err)
1408                        : "i"(SIGSEGV)
1409                        : "memory");
1410
1411                MIPS_R2_STATS(stores);
1412
1413                break;
1414
1415        case swr_op:
1416                rt = regs->regs[MIPSInst_RT(inst)];
1417                vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1418                if (!access_ok(VERIFY_WRITE, vaddr, 4)) {
1419                        current->thread.cp0_baduaddr = vaddr;
1420                        err = SIGSEGV;
1421                        break;
1422                }
1423                __asm__ __volatile__(
1424                        "       .set    push\n"
1425                        "       .set    reorder\n"
1426#ifdef CONFIG_CPU_LITTLE_ENDIAN
1427                                EXT     "%1, %0, 0, 8\n"
1428                        "1:"    SB      "%1, 0(%2)\n"
1429                                ADDIU   "%2, %2, 1\n"
1430                        "       andi    %1, %2, 0x3\n"
1431                        "       beq     $0, %1, 9f\n"
1432                                EXT     "%1, %0, 8, 8\n"
1433                        "2:"    SB      "%1, 0(%2)\n"
1434                                ADDIU   "%2, %2, 1\n"
1435                        "       andi    %1, %2, 0x3\n"
1436                        "       beq     $0, %1, 9f\n"
1437                                EXT     "%1, %0, 16, 8\n"
1438                        "3:"    SB      "%1, 0(%2)\n"
1439                                ADDIU   "%2, %2, 1\n"
1440                        "       andi    %1, %2, 0x3\n"
1441                        "       beq     $0, %1, 9f\n"
1442                                EXT     "%1, %0, 24, 8\n"
1443                        "4:"    SB      "%1, 0(%2)\n"
1444#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1445                                EXT     "%1, %0, 0, 8\n"
1446                        "1:"    SB      "%1, 0(%2)\n"
1447                        "       andi    %1, %2, 0x3\n"
1448                        "       beq     $0, %1, 9f\n"
1449                                ADDIU   "%2, %2, -1\n"
1450                                EXT     "%1, %0, 8, 8\n"
1451                        "2:"    SB      "%1, 0(%2)\n"
1452                        "       andi    %1, %2, 0x3\n"
1453                        "       beq     $0, %1, 9f\n"
1454                                ADDIU   "%2, %2, -1\n"
1455                                EXT     "%1, %0, 16, 8\n"
1456                        "3:"    SB      "%1, 0(%2)\n"
1457                        "       andi    %1, %2, 0x3\n"
1458                        "       beq     $0, %1, 9f\n"
1459                                ADDIU   "%2, %2, -1\n"
1460                                EXT     "%1, %0, 24, 8\n"
1461                        "4:"    SB      "%1, 0(%2)\n"
1462#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1463                        "9:\n"
1464                        "       .insn\n"
1465                        "       .section        .fixup,\"ax\"\n"
1466                        "8:     li      %3,%4\n"
1467                        "       j       9b\n"
1468                        "       .previous\n"
1469                        "       .section        __ex_table,\"a\"\n"
1470                        "       .word   1b,8b\n"
1471                        "       .word   2b,8b\n"
1472                        "       .word   3b,8b\n"
1473                        "       .word   4b,8b\n"
1474                        "       .previous\n"
1475                        "       .set    pop\n"
1476                        : "+&r"(rt), "=&r"(rs),
1477                          "+&r"(vaddr), "+&r"(err)
1478                        : "i"(SIGSEGV)
1479                        : "memory");
1480
1481                MIPS_R2_STATS(stores);
1482
1483                break;
1484
1485        case ldl_op:
1486                if (config_enabled(CONFIG_32BIT)) {
1487                    err = SIGILL;
1488                    break;
1489                }
1490
1491                rt = regs->regs[MIPSInst_RT(inst)];
1492                vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1493                if (!access_ok(VERIFY_READ, vaddr, 8)) {
1494                        current->thread.cp0_baduaddr = vaddr;
1495                        err = SIGSEGV;
1496                        break;
1497                }
1498                __asm__ __volatile__(
1499                        "       .set    push\n"
1500                        "       .set    reorder\n"
1501#ifdef CONFIG_CPU_LITTLE_ENDIAN
1502                        "1:     lb      %1, 0(%2)\n"
1503                        "       dinsu   %0, %1, 56, 8\n"
1504                        "       andi    %1, %2, 0x7\n"
1505                        "       beq     $0, %1, 9f\n"
1506                        "       daddiu  %2, %2, -1\n"
1507                        "2:     lb      %1, 0(%2)\n"
1508                        "       dinsu   %0, %1, 48, 8\n"
1509                        "       andi    %1, %2, 0x7\n"
1510                        "       beq     $0, %1, 9f\n"
1511                        "       daddiu  %2, %2, -1\n"
1512                        "3:     lb      %1, 0(%2)\n"
1513                        "       dinsu   %0, %1, 40, 8\n"
1514                        "       andi    %1, %2, 0x7\n"
1515                        "       beq     $0, %1, 9f\n"
1516                        "       daddiu  %2, %2, -1\n"
1517                        "4:     lb      %1, 0(%2)\n"
1518                        "       dinsu   %0, %1, 32, 8\n"
1519                        "       andi    %1, %2, 0x7\n"
1520                        "       beq     $0, %1, 9f\n"
1521                        "       daddiu  %2, %2, -1\n"
1522                        "5:     lb      %1, 0(%2)\n"
1523                        "       dins    %0, %1, 24, 8\n"
1524                        "       andi    %1, %2, 0x7\n"
1525                        "       beq     $0, %1, 9f\n"
1526                        "       daddiu  %2, %2, -1\n"
1527                        "6:     lb      %1, 0(%2)\n"
1528                        "       dins    %0, %1, 16, 8\n"
1529                        "       andi    %1, %2, 0x7\n"
1530                        "       beq     $0, %1, 9f\n"
1531                        "       daddiu  %2, %2, -1\n"
1532                        "7:     lb      %1, 0(%2)\n"
1533                        "       dins    %0, %1, 8, 8\n"
1534                        "       andi    %1, %2, 0x7\n"
1535                        "       beq     $0, %1, 9f\n"
1536                        "       daddiu  %2, %2, -1\n"
1537                        "0:     lb      %1, 0(%2)\n"
1538                        "       dins    %0, %1, 0, 8\n"
1539#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1540                        "1:     lb      %1, 0(%2)\n"
1541                        "       dinsu   %0, %1, 56, 8\n"
1542                        "       daddiu  %2, %2, 1\n"
1543                        "       andi    %1, %2, 0x7\n"
1544                        "       beq     $0, %1, 9f\n"
1545                        "2:     lb      %1, 0(%2)\n"
1546                        "       dinsu   %0, %1, 48, 8\n"
1547                        "       daddiu  %2, %2, 1\n"
1548                        "       andi    %1, %2, 0x7\n"
1549                        "       beq     $0, %1, 9f\n"
1550                        "3:     lb      %1, 0(%2)\n"
1551                        "       dinsu   %0, %1, 40, 8\n"
1552                        "       daddiu  %2, %2, 1\n"
1553                        "       andi    %1, %2, 0x7\n"
1554                        "       beq     $0, %1, 9f\n"
1555                        "4:     lb      %1, 0(%2)\n"
1556                        "       dinsu   %0, %1, 32, 8\n"
1557                        "       daddiu  %2, %2, 1\n"
1558                        "       andi    %1, %2, 0x7\n"
1559                        "       beq     $0, %1, 9f\n"
1560                        "5:     lb      %1, 0(%2)\n"
1561                        "       dins    %0, %1, 24, 8\n"
1562                        "       daddiu  %2, %2, 1\n"
1563                        "       andi    %1, %2, 0x7\n"
1564                        "       beq     $0, %1, 9f\n"
1565                        "6:     lb      %1, 0(%2)\n"
1566                        "       dins    %0, %1, 16, 8\n"
1567                        "       daddiu  %2, %2, 1\n"
1568                        "       andi    %1, %2, 0x7\n"
1569                        "       beq     $0, %1, 9f\n"
1570                        "7:     lb      %1, 0(%2)\n"
1571                        "       dins    %0, %1, 8, 8\n"
1572                        "       daddiu  %2, %2, 1\n"
1573                        "       andi    %1, %2, 0x7\n"
1574                        "       beq     $0, %1, 9f\n"
1575                        "0:     lb      %1, 0(%2)\n"
1576                        "       dins    %0, %1, 0, 8\n"
1577#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1578                        "9:\n"
1579                        "       .insn\n"
1580                        "       .section        .fixup,\"ax\"\n"
1581                        "8:     li      %3,%4\n"
1582                        "       j       9b\n"
1583                        "       .previous\n"
1584                        "       .section        __ex_table,\"a\"\n"
1585                        "       .word   1b,8b\n"
1586                        "       .word   2b,8b\n"
1587                        "       .word   3b,8b\n"
1588                        "       .word   4b,8b\n"
1589                        "       .word   5b,8b\n"
1590                        "       .word   6b,8b\n"
1591                        "       .word   7b,8b\n"
1592                        "       .word   0b,8b\n"
1593                        "       .previous\n"
1594                        "       .set    pop\n"
1595                        : "+&r"(rt), "=&r"(rs),
1596                          "+&r"(vaddr), "+&r"(err)
1597                        : "i"(SIGSEGV));
1598                if (MIPSInst_RT(inst) && !err)
1599                        regs->regs[MIPSInst_RT(inst)] = rt;
1600
1601                MIPS_R2_STATS(loads);
1602                break;
1603
1604        case ldr_op:
1605                if (config_enabled(CONFIG_32BIT)) {
1606                    err = SIGILL;
1607                    break;
1608                }
1609
1610                rt = regs->regs[MIPSInst_RT(inst)];
1611                vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1612                if (!access_ok(VERIFY_READ, vaddr, 8)) {
1613                        current->thread.cp0_baduaddr = vaddr;
1614                        err = SIGSEGV;
1615                        break;
1616                }
1617                __asm__ __volatile__(
1618                        "       .set    push\n"
1619                        "       .set    reorder\n"
1620#ifdef CONFIG_CPU_LITTLE_ENDIAN
1621                        "1:     lb      %1, 0(%2)\n"
1622                        "       dins   %0, %1, 0, 8\n"
1623                        "       daddiu  %2, %2, 1\n"
1624                        "       andi    %1, %2, 0x7\n"
1625                        "       beq     $0, %1, 9f\n"
1626                        "2:     lb      %1, 0(%2)\n"
1627                        "       dins   %0, %1, 8, 8\n"
1628                        "       daddiu  %2, %2, 1\n"
1629                        "       andi    %1, %2, 0x7\n"
1630                        "       beq     $0, %1, 9f\n"
1631                        "3:     lb      %1, 0(%2)\n"
1632                        "       dins   %0, %1, 16, 8\n"
1633                        "       daddiu  %2, %2, 1\n"
1634                        "       andi    %1, %2, 0x7\n"
1635                        "       beq     $0, %1, 9f\n"
1636                        "4:     lb      %1, 0(%2)\n"
1637                        "       dins   %0, %1, 24, 8\n"
1638                        "       daddiu  %2, %2, 1\n"
1639                        "       andi    %1, %2, 0x7\n"
1640                        "       beq     $0, %1, 9f\n"
1641                        "5:     lb      %1, 0(%2)\n"
1642                        "       dinsu    %0, %1, 32, 8\n"
1643                        "       daddiu  %2, %2, 1\n"
1644                        "       andi    %1, %2, 0x7\n"
1645                        "       beq     $0, %1, 9f\n"
1646                        "6:     lb      %1, 0(%2)\n"
1647                        "       dinsu    %0, %1, 40, 8\n"
1648                        "       daddiu  %2, %2, 1\n"
1649                        "       andi    %1, %2, 0x7\n"
1650                        "       beq     $0, %1, 9f\n"
1651                        "7:     lb      %1, 0(%2)\n"
1652                        "       dinsu    %0, %1, 48, 8\n"
1653                        "       daddiu  %2, %2, 1\n"
1654                        "       andi    %1, %2, 0x7\n"
1655                        "       beq     $0, %1, 9f\n"
1656                        "0:     lb      %1, 0(%2)\n"
1657                        "       dinsu    %0, %1, 56, 8\n"
1658#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1659                        "1:     lb      %1, 0(%2)\n"
1660                        "       dins   %0, %1, 0, 8\n"
1661                        "       andi    %1, %2, 0x7\n"
1662                        "       beq     $0, %1, 9f\n"
1663                        "       daddiu  %2, %2, -1\n"
1664                        "2:     lb      %1, 0(%2)\n"
1665                        "       dins   %0, %1, 8, 8\n"
1666                        "       andi    %1, %2, 0x7\n"
1667                        "       beq     $0, %1, 9f\n"
1668                        "       daddiu  %2, %2, -1\n"
1669                        "3:     lb      %1, 0(%2)\n"
1670                        "       dins   %0, %1, 16, 8\n"
1671                        "       andi    %1, %2, 0x7\n"
1672                        "       beq     $0, %1, 9f\n"
1673                        "       daddiu  %2, %2, -1\n"
1674                        "4:     lb      %1, 0(%2)\n"
1675                        "       dins   %0, %1, 24, 8\n"
1676                        "       andi    %1, %2, 0x7\n"
1677                        "       beq     $0, %1, 9f\n"
1678                        "       daddiu  %2, %2, -1\n"
1679                        "5:     lb      %1, 0(%2)\n"
1680                        "       dinsu    %0, %1, 32, 8\n"
1681                        "       andi    %1, %2, 0x7\n"
1682                        "       beq     $0, %1, 9f\n"
1683                        "       daddiu  %2, %2, -1\n"
1684                        "6:     lb      %1, 0(%2)\n"
1685                        "       dinsu    %0, %1, 40, 8\n"
1686                        "       andi    %1, %2, 0x7\n"
1687                        "       beq     $0, %1, 9f\n"
1688                        "       daddiu  %2, %2, -1\n"
1689                        "7:     lb      %1, 0(%2)\n"
1690                        "       dinsu    %0, %1, 48, 8\n"
1691                        "       andi    %1, %2, 0x7\n"
1692                        "       beq     $0, %1, 9f\n"
1693                        "       daddiu  %2, %2, -1\n"
1694                        "0:     lb      %1, 0(%2)\n"
1695                        "       dinsu    %0, %1, 56, 8\n"
1696#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1697                        "9:\n"
1698                        "       .insn\n"
1699                        "       .section        .fixup,\"ax\"\n"
1700                        "8:     li     %3,%4\n"
1701                        "       j      9b\n"
1702                        "       .previous\n"
1703                        "       .section        __ex_table,\"a\"\n"
1704                        "       .word  1b,8b\n"
1705                        "       .word  2b,8b\n"
1706                        "       .word  3b,8b\n"
1707                        "       .word  4b,8b\n"
1708                        "       .word  5b,8b\n"
1709                        "       .word  6b,8b\n"
1710                        "       .word  7b,8b\n"
1711                        "       .word  0b,8b\n"
1712                        "       .previous\n"
1713                        "       .set    pop\n"
1714                        : "+&r"(rt), "=&r"(rs),
1715                          "+&r"(vaddr), "+&r"(err)
1716                        : "i"(SIGSEGV));
1717                if (MIPSInst_RT(inst) && !err)
1718                        regs->regs[MIPSInst_RT(inst)] = rt;
1719
1720                MIPS_R2_STATS(loads);
1721                break;
1722
1723        case sdl_op:
1724                if (config_enabled(CONFIG_32BIT)) {
1725                    err = SIGILL;
1726                    break;
1727                }
1728
1729                rt = regs->regs[MIPSInst_RT(inst)];
1730                vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1731                if (!access_ok(VERIFY_WRITE, vaddr, 8)) {
1732                        current->thread.cp0_baduaddr = vaddr;
1733                        err = SIGSEGV;
1734                        break;
1735                }
1736                __asm__ __volatile__(
1737                        "       .set    push\n"
1738                        "       .set    reorder\n"
1739#ifdef CONFIG_CPU_LITTLE_ENDIAN
1740                        "       dextu   %1, %0, 56, 8\n"
1741                        "1:     sb      %1, 0(%2)\n"
1742                        "       andi    %1, %2, 0x7\n"
1743                        "       beq     $0, %1, 9f\n"
1744                        "       daddiu  %2, %2, -1\n"
1745                        "       dextu   %1, %0, 48, 8\n"
1746                        "2:     sb      %1, 0(%2)\n"
1747                        "       andi    %1, %2, 0x7\n"
1748                        "       beq     $0, %1, 9f\n"
1749                        "       daddiu  %2, %2, -1\n"
1750                        "       dextu   %1, %0, 40, 8\n"
1751                        "3:     sb      %1, 0(%2)\n"
1752                        "       andi    %1, %2, 0x7\n"
1753                        "       beq     $0, %1, 9f\n"
1754                        "       daddiu  %2, %2, -1\n"
1755                        "       dextu   %1, %0, 32, 8\n"
1756                        "4:     sb      %1, 0(%2)\n"
1757                        "       andi    %1, %2, 0x7\n"
1758                        "       beq     $0, %1, 9f\n"
1759                        "       daddiu  %2, %2, -1\n"
1760                        "       dext    %1, %0, 24, 8\n"
1761                        "5:     sb      %1, 0(%2)\n"
1762                        "       andi    %1, %2, 0x7\n"
1763                        "       beq     $0, %1, 9f\n"
1764                        "       daddiu  %2, %2, -1\n"
1765                        "       dext    %1, %0, 16, 8\n"
1766                        "6:     sb      %1, 0(%2)\n"
1767                        "       andi    %1, %2, 0x7\n"
1768                        "       beq     $0, %1, 9f\n"
1769                        "       daddiu  %2, %2, -1\n"
1770                        "       dext    %1, %0, 8, 8\n"
1771                        "7:     sb      %1, 0(%2)\n"
1772                        "       andi    %1, %2, 0x7\n"
1773                        "       beq     $0, %1, 9f\n"
1774                        "       daddiu  %2, %2, -1\n"
1775                        "       dext    %1, %0, 0, 8\n"
1776                        "0:     sb      %1, 0(%2)\n"
1777#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1778                        "       dextu   %1, %0, 56, 8\n"
1779                        "1:     sb      %1, 0(%2)\n"
1780                        "       daddiu  %2, %2, 1\n"
1781                        "       andi    %1, %2, 0x7\n"
1782                        "       beq     $0, %1, 9f\n"
1783                        "       dextu   %1, %0, 48, 8\n"
1784                        "2:     sb      %1, 0(%2)\n"
1785                        "       daddiu  %2, %2, 1\n"
1786                        "       andi    %1, %2, 0x7\n"
1787                        "       beq     $0, %1, 9f\n"
1788                        "       dextu   %1, %0, 40, 8\n"
1789                        "3:     sb      %1, 0(%2)\n"
1790                        "       daddiu  %2, %2, 1\n"
1791                        "       andi    %1, %2, 0x7\n"
1792                        "       beq     $0, %1, 9f\n"
1793                        "       dextu   %1, %0, 32, 8\n"
1794                        "4:     sb      %1, 0(%2)\n"
1795                        "       daddiu  %2, %2, 1\n"
1796                        "       andi    %1, %2, 0x7\n"
1797                        "       beq     $0, %1, 9f\n"
1798                        "       dext    %1, %0, 24, 8\n"
1799                        "5:     sb      %1, 0(%2)\n"
1800                        "       daddiu  %2, %2, 1\n"
1801                        "       andi    %1, %2, 0x7\n"
1802                        "       beq     $0, %1, 9f\n"
1803                        "       dext    %1, %0, 16, 8\n"
1804                        "6:     sb      %1, 0(%2)\n"
1805                        "       daddiu  %2, %2, 1\n"
1806                        "       andi    %1, %2, 0x7\n"
1807                        "       beq     $0, %1, 9f\n"
1808                        "       dext    %1, %0, 8, 8\n"
1809                        "7:     sb      %1, 0(%2)\n"
1810                        "       daddiu  %2, %2, 1\n"
1811                        "       andi    %1, %2, 0x7\n"
1812                        "       beq     $0, %1, 9f\n"
1813                        "       dext    %1, %0, 0, 8\n"
1814                        "0:     sb      %1, 0(%2)\n"
1815#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1816                        "9:\n"
1817                        "       .insn\n"
1818                        "       .section        .fixup,\"ax\"\n"
1819                        "8:     li      %3,%4\n"
1820                        "       j       9b\n"
1821                        "       .previous\n"
1822                        "       .section        __ex_table,\"a\"\n"
1823                        "       .word   1b,8b\n"
1824                        "       .word   2b,8b\n"
1825                        "       .word   3b,8b\n"
1826                        "       .word   4b,8b\n"
1827                        "       .word   5b,8b\n"
1828                        "       .word   6b,8b\n"
1829                        "       .word   7b,8b\n"
1830                        "       .word   0b,8b\n"
1831                        "       .previous\n"
1832                        "       .set    pop\n"
1833                        : "+&r"(rt), "=&r"(rs),
1834                          "+&r"(vaddr), "+&r"(err)
1835                        : "i"(SIGSEGV)
1836                        : "memory");
1837
1838                MIPS_R2_STATS(stores);
1839                break;
1840
1841        case sdr_op:
1842                if (config_enabled(CONFIG_32BIT)) {
1843                    err = SIGILL;
1844                    break;
1845                }
1846
1847                rt = regs->regs[MIPSInst_RT(inst)];
1848                vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1849                if (!access_ok(VERIFY_WRITE, vaddr, 8)) {
1850                        current->thread.cp0_baduaddr = vaddr;
1851                        err = SIGSEGV;
1852                        break;
1853                }
1854                __asm__ __volatile__(
1855                        "       .set    push\n"
1856                        "       .set    reorder\n"
1857#ifdef CONFIG_CPU_LITTLE_ENDIAN
1858                        "       dext    %1, %0, 0, 8\n"
1859                        "1:     sb      %1, 0(%2)\n"
1860                        "       daddiu  %2, %2, 1\n"
1861                        "       andi    %1, %2, 0x7\n"
1862                        "       beq     $0, %1, 9f\n"
1863                        "       dext    %1, %0, 8, 8\n"
1864                        "2:     sb      %1, 0(%2)\n"
1865                        "       daddiu  %2, %2, 1\n"
1866                        "       andi    %1, %2, 0x7\n"
1867                        "       beq     $0, %1, 9f\n"
1868                        "       dext    %1, %0, 16, 8\n"
1869                        "3:     sb      %1, 0(%2)\n"
1870                        "       daddiu  %2, %2, 1\n"
1871                        "       andi    %1, %2, 0x7\n"
1872                        "       beq     $0, %1, 9f\n"
1873                        "       dext    %1, %0, 24, 8\n"
1874                        "4:     sb      %1, 0(%2)\n"
1875                        "       daddiu  %2, %2, 1\n"
1876                        "       andi    %1, %2, 0x7\n"
1877                        "       beq     $0, %1, 9f\n"
1878                        "       dextu   %1, %0, 32, 8\n"
1879                        "5:     sb      %1, 0(%2)\n"
1880                        "       daddiu  %2, %2, 1\n"
1881                        "       andi    %1, %2, 0x7\n"
1882                        "       beq     $0, %1, 9f\n"
1883                        "       dextu   %1, %0, 40, 8\n"
1884                        "6:     sb      %1, 0(%2)\n"
1885                        "       daddiu  %2, %2, 1\n"
1886                        "       andi    %1, %2, 0x7\n"
1887                        "       beq     $0, %1, 9f\n"
1888                        "       dextu   %1, %0, 48, 8\n"
1889                        "7:     sb      %1, 0(%2)\n"
1890                        "       daddiu  %2, %2, 1\n"
1891                        "       andi    %1, %2, 0x7\n"
1892                        "       beq     $0, %1, 9f\n"
1893                        "       dextu   %1, %0, 56, 8\n"
1894                        "0:     sb      %1, 0(%2)\n"
1895#else /* !CONFIG_CPU_LITTLE_ENDIAN */
1896                        "       dext    %1, %0, 0, 8\n"
1897                        "1:     sb      %1, 0(%2)\n"
1898                        "       andi    %1, %2, 0x7\n"
1899                        "       beq     $0, %1, 9f\n"
1900                        "       daddiu  %2, %2, -1\n"
1901                        "       dext    %1, %0, 8, 8\n"
1902                        "2:     sb      %1, 0(%2)\n"
1903                        "       andi    %1, %2, 0x7\n"
1904                        "       beq     $0, %1, 9f\n"
1905                        "       daddiu  %2, %2, -1\n"
1906                        "       dext    %1, %0, 16, 8\n"
1907                        "3:     sb      %1, 0(%2)\n"
1908                        "       andi    %1, %2, 0x7\n"
1909                        "       beq     $0, %1, 9f\n"
1910                        "       daddiu  %2, %2, -1\n"
1911                        "       dext    %1, %0, 24, 8\n"
1912                        "4:     sb      %1, 0(%2)\n"
1913                        "       andi    %1, %2, 0x7\n"
1914                        "       beq     $0, %1, 9f\n"
1915                        "       daddiu  %2, %2, -1\n"
1916                        "       dextu   %1, %0, 32, 8\n"
1917                        "5:     sb      %1, 0(%2)\n"
1918                        "       andi    %1, %2, 0x7\n"
1919                        "       beq     $0, %1, 9f\n"
1920                        "       daddiu  %2, %2, -1\n"
1921                        "       dextu   %1, %0, 40, 8\n"
1922                        "6:     sb      %1, 0(%2)\n"
1923                        "       andi    %1, %2, 0x7\n"
1924                        "       beq     $0, %1, 9f\n"
1925                        "       daddiu  %2, %2, -1\n"
1926                        "       dextu   %1, %0, 48, 8\n"
1927                        "7:     sb      %1, 0(%2)\n"
1928                        "       andi    %1, %2, 0x7\n"
1929                        "       beq     $0, %1, 9f\n"
1930                        "       daddiu  %2, %2, -1\n"
1931                        "       dextu   %1, %0, 56, 8\n"
1932                        "0:     sb      %1, 0(%2)\n"
1933#endif /* CONFIG_CPU_LITTLE_ENDIAN */
1934                        "9:\n"
1935                        "       .insn\n"
1936                        "       .section        .fixup,\"ax\"\n"
1937                        "8:     li      %3,%4\n"
1938                        "       j       9b\n"
1939                        "       .previous\n"
1940                        "       .section        __ex_table,\"a\"\n"
1941                        "       .word   1b,8b\n"
1942                        "       .word   2b,8b\n"
1943                        "       .word   3b,8b\n"
1944                        "       .word   4b,8b\n"
1945                        "       .word   5b,8b\n"
1946                        "       .word   6b,8b\n"
1947                        "       .word   7b,8b\n"
1948                        "       .word   0b,8b\n"
1949                        "       .previous\n"
1950                        "       .set    pop\n"
1951                        : "+&r"(rt), "=&r"(rs),
1952                          "+&r"(vaddr), "+&r"(err)
1953                        : "i"(SIGSEGV)
1954                        : "memory");
1955
1956                MIPS_R2_STATS(stores);
1957
1958                break;
1959        case ll_op:
1960                vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
1961                if (vaddr & 0x3) {
1962                        current->thread.cp0_baduaddr = vaddr;
1963                        err = SIGBUS;
1964                        break;
1965                }
1966                if (!access_ok(VERIFY_READ, vaddr, 4)) {
1967                        current->thread.cp0_baduaddr = vaddr;
1968                        err = SIGBUS;
1969                        break;
1970                }
1971
1972                if (!cpu_has_rw_llb) {
1973                        /*
1974                         * An LL/SC block can't be safely emulated without
1975                         * a Config5/LLB availability. So it's probably time to
1976                         * kill our process before things get any worse. This is
1977                         * because Config5/LLB allows us to use ERETNC so that
1978                         * the LLAddr/LLB bit is not cleared when we return from
1979                         * an exception. MIPS R2 LL/SC instructions trap with an
1980                         * RI exception so once we emulate them here, we return
1981                         * back to userland with ERETNC. That preserves the
1982                         * LLAddr/LLB so the subsequent SC instruction will
1983                         * succeed preserving the atomic semantics of the LL/SC
1984                         * block. Without that, there is no safe way to emulate
1985                         * an LL/SC block in MIPSR2 userland.
1986                         */
1987                        pr_err("Can't emulate MIPSR2 LL/SC without Config5/LLB\n");
1988                        err = SIGKILL;
1989                        break;
1990                }
1991
1992                __asm__ __volatile__(
1993                        "1:\n"
1994                        "ll     %0, 0(%2)\n"
1995                        "2:\n"
1996                        ".insn\n"
1997                        ".section        .fixup,\"ax\"\n"
1998                        "3:\n"
1999                        "li     %1, %3\n"
2000                        "j      2b\n"
2001                        ".previous\n"
2002                        ".section        __ex_table,\"a\"\n"
2003                        ".word  1b, 3b\n"
2004                        ".previous\n"
2005                        : "=&r"(res), "+&r"(err)
2006                        : "r"(vaddr), "i"(SIGSEGV)
2007                        : "memory");
2008
2009                if (MIPSInst_RT(inst) && !err)
2010                        regs->regs[MIPSInst_RT(inst)] = res;
2011                MIPS_R2_STATS(llsc);
2012
2013                break;
2014
2015        case sc_op:
2016                vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
2017                if (vaddr & 0x3) {
2018                        current->thread.cp0_baduaddr = vaddr;
2019                        err = SIGBUS;
2020                        break;
2021                }
2022                if (!access_ok(VERIFY_WRITE, vaddr, 4)) {
2023                        current->thread.cp0_baduaddr = vaddr;
2024                        err = SIGBUS;
2025                        break;
2026                }
2027
2028                if (!cpu_has_rw_llb) {
2029                        /*
2030                         * An LL/SC block can't be safely emulated without
2031                         * a Config5/LLB availability. So it's probably time to
2032                         * kill our process before things get any worse. This is
2033                         * because Config5/LLB allows us to use ERETNC so that
2034                         * the LLAddr/LLB bit is not cleared when we return from
2035                         * an exception. MIPS R2 LL/SC instructions trap with an
2036                         * RI exception so once we emulate them here, we return
2037                         * back to userland with ERETNC. That preserves the
2038                         * LLAddr/LLB so the subsequent SC instruction will
2039                         * succeed preserving the atomic semantics of the LL/SC
2040                         * block. Without that, there is no safe way to emulate
2041                         * an LL/SC block in MIPSR2 userland.
2042                         */
2043                        pr_err("Can't emulate MIPSR2 LL/SC without Config5/LLB\n");
2044                        err = SIGKILL;
2045                        break;
2046                }
2047
2048                res = regs->regs[MIPSInst_RT(inst)];
2049
2050                __asm__ __volatile__(
2051                        "1:\n"
2052                        "sc     %0, 0(%2)\n"
2053                        "2:\n"
2054                        ".insn\n"
2055                        ".section        .fixup,\"ax\"\n"
2056                        "3:\n"
2057                        "li     %1, %3\n"
2058                        "j      2b\n"
2059                        ".previous\n"
2060                        ".section        __ex_table,\"a\"\n"
2061                        ".word  1b, 3b\n"
2062                        ".previous\n"
2063                        : "+&r"(res), "+&r"(err)
2064                        : "r"(vaddr), "i"(SIGSEGV));
2065
2066                if (MIPSInst_RT(inst) && !err)
2067                        regs->regs[MIPSInst_RT(inst)] = res;
2068
2069                MIPS_R2_STATS(llsc);
2070
2071                break;
2072
2073        case lld_op:
2074                if (config_enabled(CONFIG_32BIT)) {
2075                    err = SIGILL;
2076                    break;
2077                }
2078
2079                vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
2080                if (vaddr & 0x7) {
2081                        current->thread.cp0_baduaddr = vaddr;
2082                        err = SIGBUS;
2083                        break;
2084                }
2085                if (!access_ok(VERIFY_READ, vaddr, 8)) {
2086                        current->thread.cp0_baduaddr = vaddr;
2087                        err = SIGBUS;
2088                        break;
2089                }
2090
2091                if (!cpu_has_rw_llb) {
2092                        /*
2093                         * An LL/SC block can't be safely emulated without
2094                         * a Config5/LLB availability. So it's probably time to
2095                         * kill our process before things get any worse. This is
2096                         * because Config5/LLB allows us to use ERETNC so that
2097                         * the LLAddr/LLB bit is not cleared when we return from
2098                         * an exception. MIPS R2 LL/SC instructions trap with an
2099                         * RI exception so once we emulate them here, we return
2100                         * back to userland with ERETNC. That preserves the
2101                         * LLAddr/LLB so the subsequent SC instruction will
2102                         * succeed preserving the atomic semantics of the LL/SC
2103                         * block. Without that, there is no safe way to emulate
2104                         * an LL/SC block in MIPSR2 userland.
2105                         */
2106                        pr_err("Can't emulate MIPSR2 LL/SC without Config5/LLB\n");
2107                        err = SIGKILL;
2108                        break;
2109                }
2110
2111                __asm__ __volatile__(
2112                        "1:\n"
2113                        "lld    %0, 0(%2)\n"
2114                        "2:\n"
2115                        ".insn\n"
2116                        ".section        .fixup,\"ax\"\n"
2117                        "3:\n"
2118                        "li     %1, %3\n"
2119                        "j      2b\n"
2120                        ".previous\n"
2121                        ".section        __ex_table,\"a\"\n"
2122                        ".word  1b, 3b\n"
2123                        ".previous\n"
2124                        : "=&r"(res), "+&r"(err)
2125                        : "r"(vaddr), "i"(SIGSEGV)
2126                        : "memory");
2127                if (MIPSInst_RT(inst) && !err)
2128                        regs->regs[MIPSInst_RT(inst)] = res;
2129
2130                MIPS_R2_STATS(llsc);
2131
2132                break;
2133
2134        case scd_op:
2135                if (config_enabled(CONFIG_32BIT)) {
2136                    err = SIGILL;
2137                    break;
2138                }
2139
2140                vaddr = regs->regs[MIPSInst_RS(inst)] + MIPSInst_SIMM(inst);
2141                if (vaddr & 0x7) {
2142                        current->thread.cp0_baduaddr = vaddr;
2143                        err = SIGBUS;
2144                        break;
2145                }
2146                if (!access_ok(VERIFY_WRITE, vaddr, 8)) {
2147                        current->thread.cp0_baduaddr = vaddr;
2148                        err = SIGBUS;
2149                        break;
2150                }
2151
2152                if (!cpu_has_rw_llb) {
2153                        /*
2154                         * An LL/SC block can't be safely emulated without
2155                         * a Config5/LLB availability. So it's probably time to
2156                         * kill our process before things get any worse. This is
2157                         * because Config5/LLB allows us to use ERETNC so that
2158                         * the LLAddr/LLB bit is not cleared when we return from
2159                         * an exception. MIPS R2 LL/SC instructions trap with an
2160                         * RI exception so once we emulate them here, we return
2161                         * back to userland with ERETNC. That preserves the
2162                         * LLAddr/LLB so the subsequent SC instruction will
2163                         * succeed preserving the atomic semantics of the LL/SC
2164                         * block. Without that, there is no safe way to emulate
2165                         * an LL/SC block in MIPSR2 userland.
2166                         */
2167                        pr_err("Can't emulate MIPSR2 LL/SC without Config5/LLB\n");
2168                        err = SIGKILL;
2169                        break;
2170                }
2171
2172                res = regs->regs[MIPSInst_RT(inst)];
2173
2174                __asm__ __volatile__(
2175                        "1:\n"
2176                        "scd    %0, 0(%2)\n"
2177                        "2:\n"
2178                        ".insn\n"
2179                        ".section        .fixup,\"ax\"\n"
2180                        "3:\n"
2181                        "li     %1, %3\n"
2182                        "j      2b\n"
2183                        ".previous\n"
2184                        ".section        __ex_table,\"a\"\n"
2185                        ".word  1b, 3b\n"
2186                        ".previous\n"
2187                        : "+&r"(res), "+&r"(err)
2188                        : "r"(vaddr), "i"(SIGSEGV));
2189
2190                if (MIPSInst_RT(inst) && !err)
2191                        regs->regs[MIPSInst_RT(inst)] = res;
2192
2193                MIPS_R2_STATS(llsc);
2194
2195                break;
2196        case pref_op:
2197                /* skip it */
2198                break;
2199        default:
2200                err = SIGILL;
2201        }
2202
2203        /*
2204         * Lets not return to userland just yet. It's constly and
2205         * it's likely we have more R2 instructions to emulate
2206         */
2207        if (!err && (pass++ < MIPS_R2_EMUL_TOTAL_PASS)) {
2208                regs->cp0_cause &= ~CAUSEF_BD;
2209                err = get_user(inst, (u32 __user *)regs->cp0_epc);
2210                if (!err)
2211                        goto repeat;
2212
2213                if (err < 0)
2214                        err = SIGSEGV;
2215        }
2216
2217        if (err && (err != SIGEMT)) {
2218                regs->regs[31] = r31;
2219                regs->cp0_epc = epc;
2220        }
2221
2222        /* Likely a MIPS R6 compatible instruction */
2223        if (pass && (err == SIGILL))
2224                err = 0;
2225
2226        return err;
2227}
2228
2229#ifdef CONFIG_DEBUG_FS
2230
2231static int mipsr2_stats_show(struct seq_file *s, void *unused)
2232{
2233
2234        seq_printf(s, "Instruction\tTotal\tBDslot\n------------------------------\n");
2235        seq_printf(s, "movs\t\t%ld\t%ld\n",
2236                   (unsigned long)__this_cpu_read(mipsr2emustats.movs),
2237                   (unsigned long)__this_cpu_read(mipsr2bdemustats.movs));
2238        seq_printf(s, "hilo\t\t%ld\t%ld\n",
2239                   (unsigned long)__this_cpu_read(mipsr2emustats.hilo),
2240                   (unsigned long)__this_cpu_read(mipsr2bdemustats.hilo));
2241        seq_printf(s, "muls\t\t%ld\t%ld\n",
2242                   (unsigned long)__this_cpu_read(mipsr2emustats.muls),
2243                   (unsigned long)__this_cpu_read(mipsr2bdemustats.muls));
2244        seq_printf(s, "divs\t\t%ld\t%ld\n",
2245                   (unsigned long)__this_cpu_read(mipsr2emustats.divs),
2246                   (unsigned long)__this_cpu_read(mipsr2bdemustats.divs));
2247        seq_printf(s, "dsps\t\t%ld\t%ld\n",
2248                   (unsigned long)__this_cpu_read(mipsr2emustats.dsps),
2249                   (unsigned long)__this_cpu_read(mipsr2bdemustats.dsps));
2250        seq_printf(s, "bops\t\t%ld\t%ld\n",
2251                   (unsigned long)__this_cpu_read(mipsr2emustats.bops),
2252                   (unsigned long)__this_cpu_read(mipsr2bdemustats.bops));
2253        seq_printf(s, "traps\t\t%ld\t%ld\n",
2254                   (unsigned long)__this_cpu_read(mipsr2emustats.traps),
2255                   (unsigned long)__this_cpu_read(mipsr2bdemustats.traps));
2256        seq_printf(s, "fpus\t\t%ld\t%ld\n",
2257                   (unsigned long)__this_cpu_read(mipsr2emustats.fpus),
2258                   (unsigned long)__this_cpu_read(mipsr2bdemustats.fpus));
2259        seq_printf(s, "loads\t\t%ld\t%ld\n",
2260                   (unsigned long)__this_cpu_read(mipsr2emustats.loads),
2261                   (unsigned long)__this_cpu_read(mipsr2bdemustats.loads));
2262        seq_printf(s, "stores\t\t%ld\t%ld\n",
2263                   (unsigned long)__this_cpu_read(mipsr2emustats.stores),
2264                   (unsigned long)__this_cpu_read(mipsr2bdemustats.stores));
2265        seq_printf(s, "llsc\t\t%ld\t%ld\n",
2266                   (unsigned long)__this_cpu_read(mipsr2emustats.llsc),
2267                   (unsigned long)__this_cpu_read(mipsr2bdemustats.llsc));
2268        seq_printf(s, "dsemul\t\t%ld\t%ld\n",
2269                   (unsigned long)__this_cpu_read(mipsr2emustats.dsemul),
2270                   (unsigned long)__this_cpu_read(mipsr2bdemustats.dsemul));
2271        seq_printf(s, "jr\t\t%ld\n",
2272                   (unsigned long)__this_cpu_read(mipsr2bremustats.jrs));
2273        seq_printf(s, "bltzl\t\t%ld\n",
2274                   (unsigned long)__this_cpu_read(mipsr2bremustats.bltzl));
2275        seq_printf(s, "bgezl\t\t%ld\n",
2276                   (unsigned long)__this_cpu_read(mipsr2bremustats.bgezl));
2277        seq_printf(s, "bltzll\t\t%ld\n",
2278                   (unsigned long)__this_cpu_read(mipsr2bremustats.bltzll));
2279        seq_printf(s, "bgezll\t\t%ld\n",
2280                   (unsigned long)__this_cpu_read(mipsr2bremustats.bgezll));
2281        seq_printf(s, "bltzal\t\t%ld\n",
2282                   (unsigned long)__this_cpu_read(mipsr2bremustats.bltzal));
2283        seq_printf(s, "bgezal\t\t%ld\n",
2284                   (unsigned long)__this_cpu_read(mipsr2bremustats.bgezal));
2285        seq_printf(s, "beql\t\t%ld\n",
2286                   (unsigned long)__this_cpu_read(mipsr2bremustats.beql));
2287        seq_printf(s, "bnel\t\t%ld\n",
2288                   (unsigned long)__this_cpu_read(mipsr2bremustats.bnel));
2289        seq_printf(s, "blezl\t\t%ld\n",
2290                   (unsigned long)__this_cpu_read(mipsr2bremustats.blezl));
2291        seq_printf(s, "bgtzl\t\t%ld\n",
2292                   (unsigned long)__this_cpu_read(mipsr2bremustats.bgtzl));
2293
2294        return 0;
2295}
2296
2297static int mipsr2_stats_clear_show(struct seq_file *s, void *unused)
2298{
2299        mipsr2_stats_show(s, unused);
2300
2301        __this_cpu_write((mipsr2emustats).movs, 0);
2302        __this_cpu_write((mipsr2bdemustats).movs, 0);
2303        __this_cpu_write((mipsr2emustats).hilo, 0);
2304        __this_cpu_write((mipsr2bdemustats).hilo, 0);
2305        __this_cpu_write((mipsr2emustats).muls, 0);
2306        __this_cpu_write((mipsr2bdemustats).muls, 0);
2307        __this_cpu_write((mipsr2emustats).divs, 0);
2308        __this_cpu_write((mipsr2bdemustats).divs, 0);
2309        __this_cpu_write((mipsr2emustats).dsps, 0);
2310        __this_cpu_write((mipsr2bdemustats).dsps, 0);
2311        __this_cpu_write((mipsr2emustats).bops, 0);
2312        __this_cpu_write((mipsr2bdemustats).bops, 0);
2313        __this_cpu_write((mipsr2emustats).traps, 0);
2314        __this_cpu_write((mipsr2bdemustats).traps, 0);
2315        __this_cpu_write((mipsr2emustats).fpus, 0);
2316        __this_cpu_write((mipsr2bdemustats).fpus, 0);
2317        __this_cpu_write((mipsr2emustats).loads, 0);
2318        __this_cpu_write((mipsr2bdemustats).loads, 0);
2319        __this_cpu_write((mipsr2emustats).stores, 0);
2320        __this_cpu_write((mipsr2bdemustats).stores, 0);
2321        __this_cpu_write((mipsr2emustats).llsc, 0);
2322        __this_cpu_write((mipsr2bdemustats).llsc, 0);
2323        __this_cpu_write((mipsr2emustats).dsemul, 0);
2324        __this_cpu_write((mipsr2bdemustats).dsemul, 0);
2325        __this_cpu_write((mipsr2bremustats).jrs, 0);
2326        __this_cpu_write((mipsr2bremustats).bltzl, 0);
2327        __this_cpu_write((mipsr2bremustats).bgezl, 0);
2328        __this_cpu_write((mipsr2bremustats).bltzll, 0);
2329        __this_cpu_write((mipsr2bremustats).bgezll, 0);
2330        __this_cpu_write((mipsr2bremustats).bltzal, 0);
2331        __this_cpu_write((mipsr2bremustats).bgezal, 0);
2332        __this_cpu_write((mipsr2bremustats).beql, 0);
2333        __this_cpu_write((mipsr2bremustats).bnel, 0);
2334        __this_cpu_write((mipsr2bremustats).blezl, 0);
2335        __this_cpu_write((mipsr2bremustats).bgtzl, 0);
2336
2337        return 0;
2338}
2339
2340static int mipsr2_stats_open(struct inode *inode, struct file *file)
2341{
2342        return single_open(file, mipsr2_stats_show, inode->i_private);
2343}
2344
2345static int mipsr2_stats_clear_open(struct inode *inode, struct file *file)
2346{
2347        return single_open(file, mipsr2_stats_clear_show, inode->i_private);
2348}
2349
2350static const struct file_operations mipsr2_emul_fops = {
2351        .open                   = mipsr2_stats_open,
2352        .read                   = seq_read,
2353        .llseek                 = seq_lseek,
2354        .release                = single_release,
2355};
2356
2357static const struct file_operations mipsr2_clear_fops = {
2358        .open                   = mipsr2_stats_clear_open,
2359        .read                   = seq_read,
2360        .llseek                 = seq_lseek,
2361        .release                = single_release,
2362};
2363
2364
2365static int __init mipsr2_init_debugfs(void)
2366{
2367        struct dentry           *mipsr2_emul;
2368
2369        if (!mips_debugfs_dir)
2370                return -ENODEV;
2371
2372        mipsr2_emul = debugfs_create_file("r2_emul_stats", S_IRUGO,
2373                                          mips_debugfs_dir, NULL,
2374                                          &mipsr2_emul_fops);
2375        if (!mipsr2_emul)
2376                return -ENOMEM;
2377
2378        mipsr2_emul = debugfs_create_file("r2_emul_stats_clear", S_IRUGO,
2379                                          mips_debugfs_dir, NULL,
2380                                          &mipsr2_clear_fops);
2381        if (!mipsr2_emul)
2382                return -ENOMEM;
2383
2384        return 0;
2385}
2386
2387device_initcall(mipsr2_init_debugfs);
2388
2389#endif /* CONFIG_DEBUG_FS */
2390