arch/mips/math-emu/cp1emu.c

   1 /*
   2  * cp1emu.c: a MIPS coprocessor 1 (FPU) instruction emulator
   3  *
   4  * MIPS floating point support
   5  * Copyright (C) 1994-2000 Algorithmics Ltd.
   6  *
   7  * Kevin D. Kissell, kevink@mips.com and Carsten Langgaard, carstenl@mips.com
   8  * Copyright (C) 2000  MIPS Technologies, Inc.
   9  *
  10  *  This program is free software; you can distribute it and/or modify it
  11  *  under the terms of the GNU General Public License (Version 2) as
  12  *  published by the Free Software Foundation.
  13  *
  14  *  This program is distributed in the hope it will be useful, but WITHOUT
  15  *  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16  *  FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  17  *  for more details.
  18  *
  19  *  You should have received a copy of the GNU General Public License along
  20  *  with this program; if not, write to the Free Software Foundation, Inc.,
  21  *  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA.
  22  *
  23  * A complete emulator for MIPS coprocessor 1 instructions.  This is
  24  * required for #float(switch) or #float(trap), where it catches all
  25  * COP1 instructions via the "CoProcessor Unusable" exception.
  26  *
  27  * More surprisingly it is also required for #float(ieee), to help out
  28  * the hardware FPU at the boundaries of the IEEE-754 representation
  29  * (denormalised values, infinities, underflow, etc).  It is made
  30  * quite nasty because emulation of some non-COP1 instructions is
  31  * required, e.g. in branch delay slots.
  32  *
  33  * Note if you know that you won't have an FPU, then you'll get much
  34  * better performance by compiling with -msoft-float!
  35  */
  36 #include <linux/sched.h>
  37 #include <linux/debugfs.h>
  38 #include <linux/kconfig.h>
  39 #include <linux/percpu-defs.h>
  40 #include <linux/perf_event.h>
  41
  42 #include <asm/branch.h>
  43 #include <asm/inst.h>
  44 #include <asm/ptrace.h>
  45 #include <asm/signal.h>
  46 #include <asm/uaccess.h>
  47
  48 #include <asm/cpu-info.h>
  49 #include <asm/processor.h>
  50 #include <asm/fpu_emulator.h>
  51 #include <asm/fpu.h>
  52 #include <asm/mips-r2-to-r6-emul.h>
  53
  54 #include "ieee754.h"
  55
  56 /* Function which emulates a floating point instruction. */
  57
  58 static int fpu_emu(struct pt_regs *, struct mips_fpu_struct *,
  59         mips_instruction);
  60
  61 static int fpux_emu(struct pt_regs *,
  62         struct mips_fpu_struct *, mips_instruction, void *__user *);
  63
  64 /* Control registers */
  65
  66 #define FPCREG_RID      0       /* $0  = revision id */
  67 #define FPCREG_FCCR     25      /* $25 = fccr */
  68 #define FPCREG_FEXR     26      /* $26 = fexr */
  69 #define FPCREG_FENR     28      /* $28 = fenr */
  70 #define FPCREG_CSR      31      /* $31 = csr */
  71
  72 /* convert condition code register number to csr bit */
  73 const unsigned int fpucondbit[8] = {
  74         FPU_CSR_COND,
  75         FPU_CSR_COND1,
  76         FPU_CSR_COND2,
  77         FPU_CSR_COND3,
  78         FPU_CSR_COND4,
  79         FPU_CSR_COND5,
  80         FPU_CSR_COND6,
  81         FPU_CSR_COND7
  82 };
  83
  84 /* (microMIPS) Convert certain microMIPS instructions to MIPS32 format. */
  85 static const int sd_format[] = {16, 17, 0, 0, 0, 0, 0, 0};
  86 static const int sdps_format[] = {16, 17, 22, 0, 0, 0, 0, 0};
  87 static const int dwl_format[] = {17, 20, 21, 0, 0, 0, 0, 0};
  88 static const int swl_format[] = {16, 20, 21, 0, 0, 0, 0, 0};
  89
  90 /*
  91  * This functions translates a 32-bit microMIPS instruction
  92  * into a 32-bit MIPS32 instruction. Returns 0 on success
  93  * and SIGILL otherwise.
  94  */
  95 static int microMIPS32_to_MIPS32(union mips_instruction *insn_ptr)
  96 {
  97         union mips_instruction insn = *insn_ptr;
  98         union mips_instruction mips32_insn = insn;
  99         int func, fmt, op;
 100
 101         switch (insn.mm_i_format.opcode) {
 102         case mm_ldc132_op:
 103                 mips32_insn.mm_i_format.opcode = ldc1_op;
 104                 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
 105                 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
 106                 break;
 107         case mm_lwc132_op:
 108                 mips32_insn.mm_i_format.opcode = lwc1_op;
 109                 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
 110                 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
 111                 break;
 112         case mm_sdc132_op:
 113                 mips32_insn.mm_i_format.opcode = sdc1_op;
 114                 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
 115                 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
 116                 break;
 117         case mm_swc132_op:
 118                 mips32_insn.mm_i_format.opcode = swc1_op;
 119                 mips32_insn.mm_i_format.rt = insn.mm_i_format.rs;
 120                 mips32_insn.mm_i_format.rs = insn.mm_i_format.rt;
 121                 break;
 122         case mm_pool32i_op:
 123                 /* NOTE: offset is << by 1 if in microMIPS mode. */
 124                 if ((insn.mm_i_format.rt == mm_bc1f_op) ||
 125                     (insn.mm_i_format.rt == mm_bc1t_op)) {
 126                         mips32_insn.fb_format.opcode = cop1_op;
 127                         mips32_insn.fb_format.bc = bc_op;
 128                         mips32_insn.fb_format.flag =
 129                                 (insn.mm_i_format.rt == mm_bc1t_op) ? 1 : 0;
 130                 } else
 131                         return SIGILL;
 132                 break;
 133         case mm_pool32f_op:
 134                 switch (insn.mm_fp0_format.func) {
 135                 case mm_32f_01_op:
 136                 case mm_32f_11_op:
 137                 case mm_32f_02_op:
 138                 case mm_32f_12_op:
 139                 case mm_32f_41_op:
 140                 case mm_32f_51_op:
 141                 case mm_32f_42_op:
 142                 case mm_32f_52_op:
 143                         op = insn.mm_fp0_format.func;
 144                         if (op == mm_32f_01_op)
 145                                 func = madd_s_op;
 146                         else if (op == mm_32f_11_op)
 147                                 func = madd_d_op;
 148                         else if (op == mm_32f_02_op)
 149                                 func = nmadd_s_op;
 150                         else if (op == mm_32f_12_op)
 151                                 func = nmadd_d_op;
 152                         else if (op == mm_32f_41_op)
 153                                 func = msub_s_op;
 154                         else if (op == mm_32f_51_op)
 155                                 func = msub_d_op;
 156                         else if (op == mm_32f_42_op)
 157                                 func = nmsub_s_op;
 158                         else
 159                                 func = nmsub_d_op;
 160                         mips32_insn.fp6_format.opcode = cop1x_op;
 161                         mips32_insn.fp6_format.fr = insn.mm_fp6_format.fr;
 162                         mips32_insn.fp6_format.ft = insn.mm_fp6_format.ft;
 163                         mips32_insn.fp6_format.fs = insn.mm_fp6_format.fs;
 164                         mips32_insn.fp6_format.fd = insn.mm_fp6_format.fd;
 165                         mips32_insn.fp6_format.func = func;
 166                         break;
 167                 case mm_32f_10_op:
 168                         func = -1;      /* Invalid */
 169                         op = insn.mm_fp5_format.op & 0x7;
 170                         if (op == mm_ldxc1_op)
 171                                 func = ldxc1_op;
 172                         else if (op == mm_sdxc1_op)
 173                                 func = sdxc1_op;
 174                         else if (op == mm_lwxc1_op)
 175                                 func = lwxc1_op;
 176                         else if (op == mm_swxc1_op)
 177                                 func = swxc1_op;
 178
 179                         if (func != -1) {
 180                                 mips32_insn.r_format.opcode = cop1x_op;
 181                                 mips32_insn.r_format.rs =
 182                                         insn.mm_fp5_format.base;
 183                                 mips32_insn.r_format.rt =
 184                                         insn.mm_fp5_format.index;
 185                                 mips32_insn.r_format.rd = 0;
 186                                 mips32_insn.r_format.re = insn.mm_fp5_format.fd;
 187                                 mips32_insn.r_format.func = func;
 188                         } else
 189                                 return SIGILL;
 190                         break;
 191                 case mm_32f_40_op:
 192                         op = -1;        /* Invalid */
 193                         if (insn.mm_fp2_format.op == mm_fmovt_op)
 194                                 op = 1;
 195                         else if (insn.mm_fp2_format.op == mm_fmovf_op)
 196                                 op = 0;
 197                         if (op != -1) {
 198                                 mips32_insn.fp0_format.opcode = cop1_op;
 199                                 mips32_insn.fp0_format.fmt =
 200                                         sdps_format[insn.mm_fp2_format.fmt];
 201                                 mips32_insn.fp0_format.ft =
 202                                         (insn.mm_fp2_format.cc<<2) + op;
 203                                 mips32_insn.fp0_format.fs =
 204                                         insn.mm_fp2_format.fs;
 205                                 mips32_insn.fp0_format.fd =
 206                                         insn.mm_fp2_format.fd;
 207                                 mips32_insn.fp0_format.func = fmovc_op;
 208                         } else
 209                                 return SIGILL;
 210                         break;
 211                 case mm_32f_60_op:
 212                         func = -1;      /* Invalid */
 213                         if (insn.mm_fp0_format.op == mm_fadd_op)
 214                                 func = fadd_op;
 215                         else if (insn.mm_fp0_format.op == mm_fsub_op)
 216                                 func = fsub_op;
 217                         else if (insn.mm_fp0_format.op == mm_fmul_op)
 218                                 func = fmul_op;
 219                         else if (insn.mm_fp0_format.op == mm_fdiv_op)
 220                                 func = fdiv_op;
 221                         if (func != -1) {
 222                                 mips32_insn.fp0_format.opcode = cop1_op;
 223                                 mips32_insn.fp0_format.fmt =
 224                                         sdps_format[insn.mm_fp0_format.fmt];
 225                                 mips32_insn.fp0_format.ft =
 226                                         insn.mm_fp0_format.ft;
 227                                 mips32_insn.fp0_format.fs =
 228                                         insn.mm_fp0_format.fs;
 229                                 mips32_insn.fp0_format.fd =
 230                                         insn.mm_fp0_format.fd;
 231                                 mips32_insn.fp0_format.func = func;
 232                         } else
 233                                 return SIGILL;
 234                         break;
 235                 case mm_32f_70_op:
 236                         func = -1;      /* Invalid */
 237                         if (insn.mm_fp0_format.op == mm_fmovn_op)
 238                                 func = fmovn_op;
 239                         else if (insn.mm_fp0_format.op == mm_fmovz_op)
 240                                 func = fmovz_op;
 241                         if (func != -1) {
 242                                 mips32_insn.fp0_format.opcode = cop1_op;
 243                                 mips32_insn.fp0_format.fmt =
 244                                         sdps_format[insn.mm_fp0_format.fmt];
 245                                 mips32_insn.fp0_format.ft =
 246                                         insn.mm_fp0_format.ft;
 247                                 mips32_insn.fp0_format.fs =
 248                                         insn.mm_fp0_format.fs;
 249                                 mips32_insn.fp0_format.fd =
 250                                         insn.mm_fp0_format.fd;
 251                                 mips32_insn.fp0_format.func = func;
 252                         } else
 253                                 return SIGILL;
 254                         break;
 255                 case mm_32f_73_op:    /* POOL32FXF */
 256                         switch (insn.mm_fp1_format.op) {
 257                         case mm_movf0_op:
 258                         case mm_movf1_op:
 259                         case mm_movt0_op:
 260                         case mm_movt1_op:
 261                                 if ((insn.mm_fp1_format.op & 0x7f) ==
 262                                     mm_movf0_op)
 263                                         op = 0;
 264                                 else
 265                                         op = 1;
 266                                 mips32_insn.r_format.opcode = spec_op;
 267                                 mips32_insn.r_format.rs = insn.mm_fp4_format.fs;
 268                                 mips32_insn.r_format.rt =
 269                                         (insn.mm_fp4_format.cc << 2) + op;
 270                                 mips32_insn.r_format.rd = insn.mm_fp4_format.rt;
 271                                 mips32_insn.r_format.re = 0;
 272                                 mips32_insn.r_format.func = movc_op;
 273                                 break;
 274                         case mm_fcvtd0_op:
 275                         case mm_fcvtd1_op:
 276                         case mm_fcvts0_op:
 277                         case mm_fcvts1_op:
 278                                 if ((insn.mm_fp1_format.op & 0x7f) ==
 279                                     mm_fcvtd0_op) {
 280                                         func = fcvtd_op;
 281                                         fmt = swl_format[insn.mm_fp3_format.fmt];
 282                                 } else {
 283                                         func = fcvts_op;
 284                                         fmt = dwl_format[insn.mm_fp3_format.fmt];
 285                                 }
 286                                 mips32_insn.fp0_format.opcode = cop1_op;
 287                                 mips32_insn.fp0_format.fmt = fmt;
 288                                 mips32_insn.fp0_format.ft = 0;
 289                                 mips32_insn.fp0_format.fs =
 290                                         insn.mm_fp3_format.fs;
 291                                 mips32_insn.fp0_format.fd =
 292                                         insn.mm_fp3_format.rt;
 293                                 mips32_insn.fp0_format.func = func;
 294                                 break;
 295                         case mm_fmov0_op:
 296                         case mm_fmov1_op:
 297                         case mm_fabs0_op:
 298                         case mm_fabs1_op:
 299                         case mm_fneg0_op:
 300                         case mm_fneg1_op:
 301                                 if ((insn.mm_fp1_format.op & 0x7f) ==
 302                                     mm_fmov0_op)
 303                                         func = fmov_op;
 304                                 else if ((insn.mm_fp1_format.op & 0x7f) ==
 305                                          mm_fabs0_op)
 306                                         func = fabs_op;
 307                                 else
 308                                         func = fneg_op;
 309                                 mips32_insn.fp0_format.opcode = cop1_op;
 310                                 mips32_insn.fp0_format.fmt =
 311                                         sdps_format[insn.mm_fp3_format.fmt];
 312                                 mips32_insn.fp0_format.ft = 0;
 313                                 mips32_insn.fp0_format.fs =
 314                                         insn.mm_fp3_format.fs;
 315                                 mips32_insn.fp0_format.fd =
 316                                         insn.mm_fp3_format.rt;
 317                                 mips32_insn.fp0_format.func = func;
 318                                 break;
 319                         case mm_ffloorl_op:
 320                         case mm_ffloorw_op:
 321                         case mm_fceill_op:
 322                         case mm_fceilw_op:
 323                         case mm_ftruncl_op:
 324                         case mm_ftruncw_op:
 325                         case mm_froundl_op:
 326                         case mm_froundw_op:
 327                         case mm_fcvtl_op:
 328                         case mm_fcvtw_op:
 329                                 if (insn.mm_fp1_format.op == mm_ffloorl_op)
 330                                         func = ffloorl_op;
 331                                 else if (insn.mm_fp1_format.op == mm_ffloorw_op)
 332                                         func = ffloor_op;
 333                                 else if (insn.mm_fp1_format.op == mm_fceill_op)
 334                                         func = fceill_op;
 335                                 else if (insn.mm_fp1_format.op == mm_fceilw_op)
 336                                         func = fceil_op;
 337                                 else if (insn.mm_fp1_format.op == mm_ftruncl_op)
 338                                         func = ftruncl_op;
 339                                 else if (insn.mm_fp1_format.op == mm_ftruncw_op)
 340                                         func = ftrunc_op;
 341                                 else if (insn.mm_fp1_format.op == mm_froundl_op)
 342                                         func = froundl_op;
 343                                 else if (insn.mm_fp1_format.op == mm_froundw_op)
 344                                         func = fround_op;
 345                                 else if (insn.mm_fp1_format.op == mm_fcvtl_op)
 346                                         func = fcvtl_op;
 347                                 else
 348                                         func = fcvtw_op;
 349                                 mips32_insn.fp0_format.opcode = cop1_op;
 350                                 mips32_insn.fp0_format.fmt =
 351                                         sd_format[insn.mm_fp1_format.fmt];
 352                                 mips32_insn.fp0_format.ft = 0;
 353                                 mips32_insn.fp0_format.fs =
 354                                         insn.mm_fp1_format.fs;
 355                                 mips32_insn.fp0_format.fd =
 356                                         insn.mm_fp1_format.rt;
 357                                 mips32_insn.fp0_format.func = func;
 358                                 break;
 359                         case mm_frsqrt_op:
 360                         case mm_fsqrt_op:
 361                         case mm_frecip_op:
 362                                 if (insn.mm_fp1_format.op == mm_frsqrt_op)
 363                                         func = frsqrt_op;
 364                                 else if (insn.mm_fp1_format.op == mm_fsqrt_op)
 365                                         func = fsqrt_op;
 366                                 else
 367                                         func = frecip_op;
 368                                 mips32_insn.fp0_format.opcode = cop1_op;
 369                                 mips32_insn.fp0_format.fmt =
 370                                         sdps_format[insn.mm_fp1_format.fmt];
 371                                 mips32_insn.fp0_format.ft = 0;
 372                                 mips32_insn.fp0_format.fs =
 373                                         insn.mm_fp1_format.fs;
 374                                 mips32_insn.fp0_format.fd =
 375                                         insn.mm_fp1_format.rt;
 376                                 mips32_insn.fp0_format.func = func;
 377                                 break;
 378                         case mm_mfc1_op:
 379                         case mm_mtc1_op:
 380                         case mm_cfc1_op:
 381                         case mm_ctc1_op:
 382                         case mm_mfhc1_op:
 383                         case mm_mthc1_op:
 384                                 if (insn.mm_fp1_format.op == mm_mfc1_op)
 385                                         op = mfc_op;
 386                                 else if (insn.mm_fp1_format.op == mm_mtc1_op)
 387                                         op = mtc_op;
 388                                 else if (insn.mm_fp1_format.op == mm_cfc1_op)
 389                                         op = cfc_op;
 390                                 else if (insn.mm_fp1_format.op == mm_ctc1_op)
 391                                         op = ctc_op;
 392                                 else if (insn.mm_fp1_format.op == mm_mfhc1_op)
 393                                         op = mfhc_op;
 394                                 else
 395                                         op = mthc_op;
 396                                 mips32_insn.fp1_format.opcode = cop1_op;
 397                                 mips32_insn.fp1_format.op = op;
 398                                 mips32_insn.fp1_format.rt =
 399                                         insn.mm_fp1_format.rt;
 400                                 mips32_insn.fp1_format.fs =
 401                                         insn.mm_fp1_format.fs;
 402                                 mips32_insn.fp1_format.fd = 0;
 403                                 mips32_insn.fp1_format.func = 0;
 404                                 break;
 405                         default:
 406                                 return SIGILL;
 407                         }
 408                         break;
 409                 case mm_32f_74_op:      /* c.cond.fmt */
 410                         mips32_insn.fp0_format.opcode = cop1_op;
 411                         mips32_insn.fp0_format.fmt =
 412                                 sdps_format[insn.mm_fp4_format.fmt];
 413                         mips32_insn.fp0_format.ft = insn.mm_fp4_format.rt;
 414                         mips32_insn.fp0_format.fs = insn.mm_fp4_format.fs;
 415                         mips32_insn.fp0_format.fd = insn.mm_fp4_format.cc << 2;
 416                         mips32_insn.fp0_format.func =
 417                                 insn.mm_fp4_format.cond | MM_MIPS32_COND_FC;
 418                         break;
 419                 default:
 420                         return SIGILL;
 421                 }
 422                 break;
 423         default:
 424                 return SIGILL;
 425         }
 426
 427         *insn_ptr = mips32_insn;
 428         return 0;
 429 }
 430
 431 /*
 432  * Redundant with logic already in kernel/branch.c,
 433  * embedded in compute_return_epc.  At some point,
 434  * a single subroutine should be used across both
 435  * modules.
 436  */
 437 static int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn,
 438                          unsigned long *contpc)
 439 {
 440         union mips_instruction insn = (union mips_instruction)dec_insn.insn;
 441         unsigned int fcr31;
 442         unsigned int bit = 0;
 443
 444         switch (insn.i_format.opcode) {
 445         case spec_op:
 446                 switch (insn.r_format.func) {
 447                 case jalr_op:
 448                         regs->regs[insn.r_format.rd] =
 449                                 regs->cp0_epc + dec_insn.pc_inc +
 450                                 dec_insn.next_pc_inc;
 451                         /* Fall through */
 452                 case jr_op:
 453                         /* For R6, JR already emulated in jalr_op */
 454                         if (NO_R6EMU && insn.r_format.func == jr_op)
 455                                 break;
 456                         *contpc = regs->regs[insn.r_format.rs];
 457                         return 1;
 458                 }
 459                 break;
 460         case bcond_op:
 461                 switch (insn.i_format.rt) {
 462                 case bltzal_op:
 463                 case bltzall_op:
 464                         if (NO_R6EMU && (insn.i_format.rs ||
 465                             insn.i_format.rt == bltzall_op))
 466                                 break;
 467
 468                         regs->regs[31] = regs->cp0_epc +
 469                                 dec_insn.pc_inc +
 470                                 dec_insn.next_pc_inc;
 471                         /* Fall through */
 472                 case bltzl_op:
 473                         if (NO_R6EMU)
 474                                 break;
 475                 case bltz_op:
 476                         if ((long)regs->regs[insn.i_format.rs] < 0)
 477                                 *contpc = regs->cp0_epc +
 478                                         dec_insn.pc_inc +
 479                                         (insn.i_format.simmediate << 2);
 480                         else
 481                                 *contpc = regs->cp0_epc +
 482                                         dec_insn.pc_inc +
 483                                         dec_insn.next_pc_inc;
 484                         return 1;
 485                 case bgezal_op:
 486                 case bgezall_op:
 487                         if (NO_R6EMU && (insn.i_format.rs ||
 488                             insn.i_format.rt == bgezall_op))
 489                                 break;
 490
 491                         regs->regs[31] = regs->cp0_epc +
 492                                 dec_insn.pc_inc +
 493                                 dec_insn.next_pc_inc;
 494                         /* Fall through */
 495                 case bgezl_op:
 496                         if (NO_R6EMU)
 497                                 break;
 498                 case bgez_op:
 499                         if ((long)regs->regs[insn.i_format.rs] >= 0)
 500                                 *contpc = regs->cp0_epc +
 501                                         dec_insn.pc_inc +
 502                                         (insn.i_format.simmediate << 2);
 503                         else
 504                                 *contpc = regs->cp0_epc +
 505                                         dec_insn.pc_inc +
 506                                         dec_insn.next_pc_inc;
 507                         return 1;
 508                 }
 509                 break;
 510         case jalx_op:
 511                 set_isa16_mode(bit);
 512         case jal_op:
 513                 regs->regs[31] = regs->cp0_epc +
 514                         dec_insn.pc_inc +
 515                         dec_insn.next_pc_inc;
 516                 /* Fall through */
 517         case j_op:
 518                 *contpc = regs->cp0_epc + dec_insn.pc_inc;
 519                 *contpc >>= 28;
 520                 *contpc <<= 28;
 521                 *contpc |= (insn.j_format.target << 2);
 522                 /* Set microMIPS mode bit: XOR for jalx. */
 523                 *contpc ^= bit;
 524                 return 1;
 525         case beql_op:
 526                 if (NO_R6EMU)
 527                         break;
 528         case beq_op:
 529                 if (regs->regs[insn.i_format.rs] ==
 530                     regs->regs[insn.i_format.rt])
 531                         *contpc = regs->cp0_epc +
 532                                 dec_insn.pc_inc +
 533                                 (insn.i_format.simmediate << 2);
 534                 else
 535                         *contpc = regs->cp0_epc +
 536                                 dec_insn.pc_inc +
 537                                 dec_insn.next_pc_inc;
 538                 return 1;
 539         case bnel_op:
 540                 if (NO_R6EMU)
 541                         break;
 542         case bne_op:
 543                 if (regs->regs[insn.i_format.rs] !=
 544                     regs->regs[insn.i_format.rt])
 545                         *contpc = regs->cp0_epc +
 546                                 dec_insn.pc_inc +
 547                                 (insn.i_format.simmediate << 2);
 548                 else
 549                         *contpc = regs->cp0_epc +
 550                                 dec_insn.pc_inc +
 551                                 dec_insn.next_pc_inc;
 552                 return 1;
 553         case blezl_op:
 554                 if (!insn.i_format.rt && NO_R6EMU)
 555                         break;
 556         case blez_op:
 557
 558                 /*
 559                  * Compact branches for R6 for the
 560                  * blez and blezl opcodes.
 561                  * BLEZ  | rs = 0 | rt != 0  == BLEZALC
 562                  * BLEZ  | rs = rt != 0      == BGEZALC
 563                  * BLEZ  | rs != 0 | rt != 0 == BGEUC
 564                  * BLEZL | rs = 0 | rt != 0  == BLEZC
 565                  * BLEZL | rs = rt != 0      == BGEZC
 566                  * BLEZL | rs != 0 | rt != 0 == BGEC
 567                  *
 568                  * For real BLEZ{,L}, rt is always 0.
 569                  */
 570                 if (cpu_has_mips_r6 && insn.i_format.rt) {
 571                         if ((insn.i_format.opcode == blez_op) &&
 572                             ((!insn.i_format.rs && insn.i_format.rt) ||
 573                              (insn.i_format.rs == insn.i_format.rt)))
 574                                 regs->regs[31] = regs->cp0_epc +
 575                                         dec_insn.pc_inc;
 576                         *contpc = regs->cp0_epc + dec_insn.pc_inc +
 577                                 dec_insn.next_pc_inc;
 578
 579                         return 1;
 580                 }
 581                 if ((long)regs->regs[insn.i_format.rs] <= 0)
 582                         *contpc = regs->cp0_epc +
 583                                 dec_insn.pc_inc +
 584                                 (insn.i_format.simmediate << 2);
 585                 else
 586                         *contpc = regs->cp0_epc +
 587                                 dec_insn.pc_inc +
 588                                 dec_insn.next_pc_inc;
 589                 return 1;
 590         case bgtzl_op:
 591                 if (!insn.i_format.rt && NO_R6EMU)
 592                         break;
 593         case bgtz_op:
 594                 /*
 595                  * Compact branches for R6 for the
 596                  * bgtz and bgtzl opcodes.
 597                  * BGTZ  | rs = 0 | rt != 0  == BGTZALC
 598                  * BGTZ  | rs = rt != 0      == BLTZALC
 599                  * BGTZ  | rs != 0 | rt != 0 == BLTUC
 600                  * BGTZL | rs = 0 | rt != 0  == BGTZC
 601                  * BGTZL | rs = rt != 0      == BLTZC
 602                  * BGTZL | rs != 0 | rt != 0 == BLTC
 603                  *
 604                  * *ZALC varint for BGTZ &&& rt != 0
 605                  * For real GTZ{,L}, rt is always 0.
 606                  */
 607                 if (cpu_has_mips_r6 && insn.i_format.rt) {
 608                         if ((insn.i_format.opcode == blez_op) &&
 609                             ((!insn.i_format.rs && insn.i_format.rt) ||
 610                              (insn.i_format.rs == insn.i_format.rt)))
 611                                 regs->regs[31] = regs->cp0_epc +
 612                                         dec_insn.pc_inc;
 613                         *contpc = regs->cp0_epc + dec_insn.pc_inc +
 614                                 dec_insn.next_pc_inc;
 615
 616                         return 1;
 617                 }
 618
 619                 if ((long)regs->regs[insn.i_format.rs] > 0)
 620                         *contpc = regs->cp0_epc +
 621                                 dec_insn.pc_inc +
 622                                 (insn.i_format.simmediate << 2);
 623                 else
 624                         *contpc = regs->cp0_epc +
 625                                 dec_insn.pc_inc +
 626                                 dec_insn.next_pc_inc;
 627                 return 1;
 628         case cbcond0_op:
 629         case cbcond1_op:
 630                 if (!cpu_has_mips_r6)
 631                         break;
 632                 if (insn.i_format.rt && !insn.i_format.rs)
 633                         regs->regs[31] = regs->cp0_epc + 4;
 634                 *contpc = regs->cp0_epc + dec_insn.pc_inc +
 635                         dec_insn.next_pc_inc;
 636
 637                 return 1;
 638 #ifdef CONFIG_CPU_CAVIUM_OCTEON
 639         case lwc2_op: /* This is bbit0 on Octeon */
 640                 if ((regs->regs[insn.i_format.rs] & (1ull<<insn.i_format.rt)) == 0)
 641                         *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
 642                 else
 643                         *contpc = regs->cp0_epc + 8;
 644                 return 1;
 645         case ldc2_op: /* This is bbit032 on Octeon */
 646                 if ((regs->regs[insn.i_format.rs] & (1ull<<(insn.i_format.rt + 32))) == 0)
 647                         *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
 648                 else
 649                         *contpc = regs->cp0_epc + 8;
 650                 return 1;
 651         case swc2_op: /* This is bbit1 on Octeon */
 652                 if (regs->regs[insn.i_format.rs] & (1ull<<insn.i_format.rt))
 653                         *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
 654                 else
 655                         *contpc = regs->cp0_epc + 8;
 656                 return 1;
 657         case sdc2_op: /* This is bbit132 on Octeon */
 658                 if (regs->regs[insn.i_format.rs] & (1ull<<(insn.i_format.rt + 32)))
 659                         *contpc = regs->cp0_epc + 4 + (insn.i_format.simmediate << 2);
 660                 else
 661                         *contpc = regs->cp0_epc + 8;
 662                 return 1;
 663 #else
 664         case bc6_op:
 665                 /*
 666                  * Only valid for MIPS R6 but we can still end up
 667                  * here from a broken userland so just tell emulator
 668                  * this is not a branch and let it break later on.
 669                  */
 670                 if  (!cpu_has_mips_r6)
 671                         break;
 672                 *contpc = regs->cp0_epc + dec_insn.pc_inc +
 673                         dec_insn.next_pc_inc;
 674
 675                 return 1;
 676         case balc6_op:
 677                 if (!cpu_has_mips_r6)
 678                         break;
 679                 regs->regs[31] = regs->cp0_epc + 4;
 680                 *contpc = regs->cp0_epc + dec_insn.pc_inc +
 681                         dec_insn.next_pc_inc;
 682
 683                 return 1;
 684         case beqzcjic_op:
 685                 if (!cpu_has_mips_r6)
 686                         break;
 687                 *contpc = regs->cp0_epc + dec_insn.pc_inc +
 688                         dec_insn.next_pc_inc;
 689
 690                 return 1;
 691         case bnezcjialc_op:
 692                 if (!cpu_has_mips_r6)
 693                         break;
 694                 if (!insn.i_format.rs)
 695                         regs->regs[31] = regs->cp0_epc + 4;
 696                 *contpc = regs->cp0_epc + dec_insn.pc_inc +
 697                         dec_insn.next_pc_inc;
 698
 699                 return 1;
 700 #endif
 701         case cop0_op:
 702         case cop1_op:
 703                 /* Need to check for R6 bc1nez and bc1eqz branches */
 704                 if (cpu_has_mips_r6 &&
 705                     ((insn.i_format.rs == bc1eqz_op) ||
 706                      (insn.i_format.rs == bc1nez_op))) {
 707                         bit = 0;
 708                         switch (insn.i_format.rs) {
 709                         case bc1eqz_op:
 710                                 if (get_fpr32(&current->thread.fpu.fpr[insn.i_format.rt], 0) & 0x1)
 711                                     bit = 1;
 712                                 break;
 713                         case bc1nez_op:
 714                                 if (!(get_fpr32(&current->thread.fpu.fpr[insn.i_format.rt], 0) & 0x1))
 715                                     bit = 1;
 716                                 break;
 717                         }
 718                         if (bit)
 719                                 *contpc = regs->cp0_epc +
 720                                         dec_insn.pc_inc +
 721                                         (insn.i_format.simmediate << 2);
 722                         else
 723                                 *contpc = regs->cp0_epc +
 724                                         dec_insn.pc_inc +
 725                                         dec_insn.next_pc_inc;
 726
 727                         return 1;
 728                 }
 729                 /* R2/R6 compatible cop1 instruction. Fall through */
 730         case cop2_op:
 731         case cop1x_op:
 732                 if (insn.i_format.rs == bc_op) {
 733                         preempt_disable();
 734                         if (is_fpu_owner())
 735                                 fcr31 = read_32bit_cp1_register(CP1_STATUS);
 736                         else
 737                                 fcr31 = current->thread.fpu.fcr31;
 738                         preempt_enable();
 739
 740                         bit = (insn.i_format.rt >> 2);
 741                         bit += (bit != 0);
 742                         bit += 23;
 743                         switch (insn.i_format.rt & 3) {
 744                         case 0: /* bc1f */
 745                         case 2: /* bc1fl */
 746                                 if (~fcr31 & (1 << bit))
 747                                         *contpc = regs->cp0_epc +
 748                                                 dec_insn.pc_inc +
 749                                                 (insn.i_format.simmediate << 2);
 750                                 else
 751                                         *contpc = regs->cp0_epc +
 752                                                 dec_insn.pc_inc +
 753                                                 dec_insn.next_pc_inc;
 754                                 return 1;
 755                         case 1: /* bc1t */
 756                         case 3: /* bc1tl */
 757                                 if (fcr31 & (1 << bit))
 758                                         *contpc = regs->cp0_epc +
 759                                                 dec_insn.pc_inc +
 760                                                 (insn.i_format.simmediate << 2);
 761                                 else
 762                                         *contpc = regs->cp0_epc +
 763                                                 dec_insn.pc_inc +
 764                                                 dec_insn.next_pc_inc;
 765                                 return 1;
 766                         }
 767                 }
 768                 break;
 769         }
 770         return 0;
 771 }
 772
 773 /*
 774  * In the Linux kernel, we support selection of FPR format on the
 775  * basis of the Status.FR bit.  If an FPU is not present, the FR bit
 776  * is hardwired to zero, which would imply a 32-bit FPU even for
 777  * 64-bit CPUs so we rather look at TIF_32BIT_FPREGS.
 778  * FPU emu is slow and bulky and optimizing this function offers fairly
 779  * sizeable benefits so we try to be clever and make this function return
 780  * a constant whenever possible, that is on 64-bit kernels without O32
 781  * compatibility enabled and on 32-bit without 64-bit FPU support.
 782  */
 783 static inline int cop1_64bit(struct pt_regs *xcp)
 784 {
 785         if (config_enabled(CONFIG_64BIT) && !config_enabled(CONFIG_MIPS32_O32))
 786                 return 1;
 787         else if (config_enabled(CONFIG_32BIT) &&
 788                  !config_enabled(CONFIG_MIPS_O32_FP64_SUPPORT))
 789                 return 0;
 790
 791         return !test_thread_flag(TIF_32BIT_FPREGS);
 792 }
 793
 794 static inline bool hybrid_fprs(void)
 795 {
 796         return test_thread_flag(TIF_HYBRID_FPREGS);
 797 }
 798
 799 #define SIFROMREG(si, x)                                                \
 800 do {                                                                    \
 801         if (cop1_64bit(xcp) && !hybrid_fprs())                          \
 802                 (si) = (int)get_fpr32(&ctx->fpr[x], 0);                 \
 803         else                                                            \
 804                 (si) = (int)get_fpr32(&ctx->fpr[(x) & ~1], (x) & 1);    \
 805 } while (0)
 806
 807 #define SITOREG(si, x)                                                  \
 808 do {                                                                    \
 809         if (cop1_64bit(xcp) && !hybrid_fprs()) {                        \
 810                 unsigned i;                                             \
 811                 set_fpr32(&ctx->fpr[x], 0, si);                         \
 812                 for (i = 1; i < ARRAY_SIZE(ctx->fpr[x].val32); i++)     \
 813                         set_fpr32(&ctx->fpr[x], i, 0);                  \
 814         } else {                                                        \
 815                 set_fpr32(&ctx->fpr[(x) & ~1], (x) & 1, si);            \
 816         }                                                               \
 817 } while (0)
 818
 819 #define SIFROMHREG(si, x)       ((si) = (int)get_fpr32(&ctx->fpr[x], 1))
 820
 821 #define SITOHREG(si, x)                                                 \
 822 do {                                                                    \
 823         unsigned i;                                                     \
 824         set_fpr32(&ctx->fpr[x], 1, si);                                 \
 825         for (i = 2; i < ARRAY_SIZE(ctx->fpr[x].val32); i++)             \
 826                 set_fpr32(&ctx->fpr[x], i, 0);                          \
 827 } while (0)
 828
 829 #define DIFROMREG(di, x)                                                \
 830         ((di) = get_fpr64(&ctx->fpr[(x) & ~(cop1_64bit(xcp) == 0)], 0))
 831
 832 #define DITOREG(di, x)                                                  \
 833 do {                                                                    \
 834         unsigned fpr, i;                                                \
 835         fpr = (x) & ~(cop1_64bit(xcp) == 0);                            \
 836         set_fpr64(&ctx->fpr[fpr], 0, di);                               \
 837         for (i = 1; i < ARRAY_SIZE(ctx->fpr[x].val64); i++)             \
 838                 set_fpr64(&ctx->fpr[fpr], i, 0);                        \
 839 } while (0)
 840
 841 #define SPFROMREG(sp, x) SIFROMREG((sp).bits, x)
 842 #define SPTOREG(sp, x)  SITOREG((sp).bits, x)
 843 #define DPFROMREG(dp, x)        DIFROMREG((dp).bits, x)
 844 #define DPTOREG(dp, x)  DITOREG((dp).bits, x)
 845
 846 /*
 847  * Emulate a CFC1 instruction.
 848  */
 849 static inline void cop1_cfc(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 850                             mips_instruction ir)
 851 {
 852         u32 fcr31 = ctx->fcr31;
 853         u32 value = 0;
 854
 855         switch (MIPSInst_RD(ir)) {
 856         case FPCREG_CSR:
 857                 value = fcr31;
 858                 pr_debug("%p gpr[%d]<-csr=%08x\n",
 859                          (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
 860                 break;
 861
 862         case FPCREG_FENR:
 863                 if (!cpu_has_mips_r)
 864                         break;
 865                 value = (fcr31 >> (FPU_CSR_FS_S - MIPS_FENR_FS_S)) &
 866                         MIPS_FENR_FS;
 867                 value |= fcr31 & (FPU_CSR_ALL_E | FPU_CSR_RM);
 868                 pr_debug("%p gpr[%d]<-enr=%08x\n",
 869                          (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
 870                 break;
 871
 872         case FPCREG_FEXR:
 873                 if (!cpu_has_mips_r)
 874                         break;
 875                 value = fcr31 & (FPU_CSR_ALL_X | FPU_CSR_ALL_S);
 876                 pr_debug("%p gpr[%d]<-exr=%08x\n",
 877                          (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
 878                 break;
 879
 880         case FPCREG_FCCR:
 881                 if (!cpu_has_mips_r)
 882                         break;
 883                 value = (fcr31 >> (FPU_CSR_COND_S - MIPS_FCCR_COND0_S)) &
 884                         MIPS_FCCR_COND0;
 885                 value |= (fcr31 >> (FPU_CSR_COND1_S - MIPS_FCCR_COND1_S)) &
 886                          (MIPS_FCCR_CONDX & ~MIPS_FCCR_COND0);
 887                 pr_debug("%p gpr[%d]<-ccr=%08x\n",
 888                          (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
 889                 break;
 890
 891         case FPCREG_RID:
 892                 value = boot_cpu_data.fpu_id;
 893                 break;
 894
 895         default:
 896                 break;
 897         }
 898
 899         if (MIPSInst_RT(ir))
 900                 xcp->regs[MIPSInst_RT(ir)] = value;
 901 }
 902
 903 /*
 904  * Emulate a CTC1 instruction.
 905  */
 906 static inline void cop1_ctc(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 907                             mips_instruction ir)
 908 {
 909         u32 fcr31 = ctx->fcr31;
 910         u32 value;
 911         u32 mask;
 912
 913         if (MIPSInst_RT(ir) == 0)
 914                 value = 0;
 915         else
 916                 value = xcp->regs[MIPSInst_RT(ir)];
 917
 918         switch (MIPSInst_RD(ir)) {
 919         case FPCREG_CSR:
 920                 pr_debug("%p gpr[%d]->csr=%08x\n",
 921                          (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
 922
 923                 /* Preserve read-only bits.  */
 924                 mask = boot_cpu_data.fpu_msk31;
 925                 fcr31 = (value & ~mask) | (fcr31 & mask);
 926                 break;
 927
 928         case FPCREG_FENR:
 929                 if (!cpu_has_mips_r)
 930                         break;
 931                 pr_debug("%p gpr[%d]->enr=%08x\n",
 932                          (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
 933                 fcr31 &= ~(FPU_CSR_FS | FPU_CSR_ALL_E | FPU_CSR_RM);
 934                 fcr31 |= (value << (FPU_CSR_FS_S - MIPS_FENR_FS_S)) &
 935                          FPU_CSR_FS;
 936                 fcr31 |= value & (FPU_CSR_ALL_E | FPU_CSR_RM);
 937                 break;
 938
 939         case FPCREG_FEXR:
 940                 if (!cpu_has_mips_r)
 941                         break;
 942                 pr_debug("%p gpr[%d]->exr=%08x\n",
 943                          (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
 944                 fcr31 &= ~(FPU_CSR_ALL_X | FPU_CSR_ALL_S);
 945                 fcr31 |= value & (FPU_CSR_ALL_X | FPU_CSR_ALL_S);
 946                 break;
 947
 948         case FPCREG_FCCR:
 949                 if (!cpu_has_mips_r)
 950                         break;
 951                 pr_debug("%p gpr[%d]->ccr=%08x\n",
 952                          (void *)xcp->cp0_epc, MIPSInst_RT(ir), value);
 953                 fcr31 &= ~(FPU_CSR_CONDX | FPU_CSR_COND);
 954                 fcr31 |= (value << (FPU_CSR_COND_S - MIPS_FCCR_COND0_S)) &
 955                          FPU_CSR_COND;
 956                 fcr31 |= (value << (FPU_CSR_COND1_S - MIPS_FCCR_COND1_S)) &
 957                          FPU_CSR_CONDX;
 958                 break;
 959
 960         default:
 961                 break;
 962         }
 963
 964         ctx->fcr31 = fcr31;
 965 }
 966
 967 /*
 968  * Emulate the single floating point instruction pointed at by EPC.
 969  * Two instructions if the instruction is in a branch delay slot.
 970  */
 971
 972 static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 973                 struct mm_decoded_insn dec_insn, void *__user *fault_addr)
 974 {
 975         unsigned long contpc = xcp->cp0_epc + dec_insn.pc_inc;
 976         unsigned int cond, cbit;
 977         mips_instruction ir;
 978         int likely, pc_inc;
 979         u32 __user *wva;
 980         u64 __user *dva;
 981         u32 wval;
 982         u64 dval;
 983         int sig;
 984
 985         /*
 986          * These are giving gcc a gentle hint about what to expect in
 987          * dec_inst in order to do better optimization.
 988          */
 989         if (!cpu_has_mmips && dec_insn.micro_mips_mode)
 990                 unreachable();
 991
 992         /* XXX NEC Vr54xx bug workaround */
 993         if (delay_slot(xcp)) {
 994                 if (dec_insn.micro_mips_mode) {
 995                         if (!mm_isBranchInstr(xcp, dec_insn, &contpc))
 996                                 clear_delay_slot(xcp);
 997                 } else {
 998                         if (!isBranchInstr(xcp, dec_insn, &contpc))
 999                                 clear_delay_slot(xcp);
1000                 }
1001         }
1002
1003         if (delay_slot(xcp)) {
1004                 /*
1005                  * The instruction to be emulated is in a branch delay slot
1006                  * which means that we have to  emulate the branch instruction
1007                  * BEFORE we do the cop1 instruction.
1008                  *
1009                  * This branch could be a COP1 branch, but in that case we
1010                  * would have had a trap for that instruction, and would not
1011                  * come through this route.
1012                  *
1013                  * Linux MIPS branch emulator operates on context, updating the
1014                  * cp0_epc.
1015                  */
1016                 ir = dec_insn.next_insn;  /* process delay slot instr */
1017                 pc_inc = dec_insn.next_pc_inc;
1018         } else {
1019                 ir = dec_insn.insn;       /* process current instr */
1020                 pc_inc = dec_insn.pc_inc;
1021         }
1022
1023         /*
1024          * Since microMIPS FPU instructios are a subset of MIPS32 FPU
1025          * instructions, we want to convert microMIPS FPU instructions
1026          * into MIPS32 instructions so that we could reuse all of the
1027          * FPU emulation code.
1028          *
1029          * NOTE: We cannot do this for branch instructions since they
1030          *       are not a subset. Example: Cannot emulate a 16-bit
1031          *       aligned target address with a MIPS32 instruction.
1032          */
1033         if (dec_insn.micro_mips_mode) {
1034                 /*
1035                  * If next instruction is a 16-bit instruction, then it
1036                  * it cannot be a FPU instruction. This could happen
1037                  * since we can be called for non-FPU instructions.
1038                  */
1039                 if ((pc_inc == 2) ||
1040                         (microMIPS32_to_MIPS32((union mips_instruction *)&ir)
1041                          == SIGILL))
1042                         return SIGILL;
1043         }
1044
1045 emul:
1046         perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, xcp, 0);
1047         MIPS_FPU_EMU_INC_STATS(emulated);
1048         switch (MIPSInst_OPCODE(ir)) {
1049         case ldc1_op:
1050                 dva = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1051                                      MIPSInst_SIMM(ir));
1052                 MIPS_FPU_EMU_INC_STATS(loads);
1053
1054                 if (!access_ok(VERIFY_READ, dva, sizeof(u64))) {
1055                         MIPS_FPU_EMU_INC_STATS(errors);
1056                         *fault_addr = dva;
1057                         return SIGBUS;
1058                 }
1059                 if (__get_user(dval, dva)) {
1060                         MIPS_FPU_EMU_INC_STATS(errors);
1061                         *fault_addr = dva;
1062                         return SIGSEGV;
1063                 }
1064                 DITOREG(dval, MIPSInst_RT(ir));
1065                 break;
1066
1067         case sdc1_op:
1068                 dva = (u64 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1069                                       MIPSInst_SIMM(ir));
1070                 MIPS_FPU_EMU_INC_STATS(stores);
1071                 DIFROMREG(dval, MIPSInst_RT(ir));
1072                 if (!access_ok(VERIFY_WRITE, dva, sizeof(u64))) {
1073                         MIPS_FPU_EMU_INC_STATS(errors);
1074                         *fault_addr = dva;
1075                         return SIGBUS;
1076                 }
1077                 if (__put_user(dval, dva)) {
1078                         MIPS_FPU_EMU_INC_STATS(errors);
1079                         *fault_addr = dva;
1080                         return SIGSEGV;
1081                 }
1082                 break;
1083
1084         case lwc1_op:
1085                 wva = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1086                                       MIPSInst_SIMM(ir));
1087                 MIPS_FPU_EMU_INC_STATS(loads);
1088                 if (!access_ok(VERIFY_READ, wva, sizeof(u32))) {
1089                         MIPS_FPU_EMU_INC_STATS(errors);
1090                         *fault_addr = wva;
1091                         return SIGBUS;
1092                 }
1093                 if (__get_user(wval, wva)) {
1094                         MIPS_FPU_EMU_INC_STATS(errors);
1095                         *fault_addr = wva;
1096                         return SIGSEGV;
1097                 }
1098                 SITOREG(wval, MIPSInst_RT(ir));
1099                 break;
1100
1101         case swc1_op:
1102                 wva = (u32 __user *) (xcp->regs[MIPSInst_RS(ir)] +
1103                                       MIPSInst_SIMM(ir));
1104                 MIPS_FPU_EMU_INC_STATS(stores);
1105                 SIFROMREG(wval, MIPSInst_RT(ir));
1106                 if (!access_ok(VERIFY_WRITE, wva, sizeof(u32))) {
1107                         MIPS_FPU_EMU_INC_STATS(errors);
1108                         *fault_addr = wva;
1109                         return SIGBUS;
1110                 }
1111                 if (__put_user(wval, wva)) {
1112                         MIPS_FPU_EMU_INC_STATS(errors);
1113                         *fault_addr = wva;
1114                         return SIGSEGV;
1115                 }
1116                 break;
1117
1118         case cop1_op:
1119                 switch (MIPSInst_RS(ir)) {
1120                 case dmfc_op:
1121                         if (!cpu_has_mips_3_4_5 && !cpu_has_mips64)
1122                                 return SIGILL;
1123
1124                         /* copregister fs -> gpr[rt] */
1125                         if (MIPSInst_RT(ir) != 0) {
1126                                 DIFROMREG(xcp->regs[MIPSInst_RT(ir)],
1127                                         MIPSInst_RD(ir));
1128                         }
1129                         break;
1130
1131                 case dmtc_op:
1132                         if (!cpu_has_mips_3_4_5 && !cpu_has_mips64)
1133                                 return SIGILL;
1134
1135                         /* copregister fs <- rt */
1136                         DITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
1137                         break;
1138
1139                 case mfhc_op:
1140                         if (!cpu_has_mips_r2_r6)
1141                                 goto sigill;
1142
1143                         /* copregister rd -> gpr[rt] */
1144                         if (MIPSInst_RT(ir) != 0) {
1145                                 SIFROMHREG(xcp->regs[MIPSInst_RT(ir)],
1146                                         MIPSInst_RD(ir));
1147                         }
1148                         break;
1149
1150                 case mthc_op:
1151                         if (!cpu_has_mips_r2_r6)
1152                                 goto sigill;
1153
1154                         /* copregister rd <- gpr[rt] */
1155                         SITOHREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
1156                         break;
1157
1158                 case mfc_op:
1159                         /* copregister rd -> gpr[rt] */
1160                         if (MIPSInst_RT(ir) != 0) {
1161                                 SIFROMREG(xcp->regs[MIPSInst_RT(ir)],
1162                                         MIPSInst_RD(ir));
1163                         }
1164                         break;
1165
1166                 case mtc_op:
1167                         /* copregister rd <- rt */
1168                         SITOREG(xcp->regs[MIPSInst_RT(ir)], MIPSInst_RD(ir));
1169                         break;
1170
1171                 case cfc_op:
1172                         /* cop control register rd -> gpr[rt] */
1173                         cop1_cfc(xcp, ctx, ir);
1174                         break;
1175
1176                 case ctc_op:
1177                         /* copregister rd <- rt */
1178                         cop1_ctc(xcp, ctx, ir);
1179                         if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
1180                                 return SIGFPE;
1181                         }
1182                         break;
1183
1184                 case bc1eqz_op:
1185                 case bc1nez_op:
1186                         if (!cpu_has_mips_r6 || delay_slot(xcp))
1187                                 return SIGILL;
1188
1189                         cond = likely = 0;
1190                         switch (MIPSInst_RS(ir)) {
1191                         case bc1eqz_op:
1192                                 if (get_fpr32(&current->thread.fpu.fpr[MIPSInst_RT(ir)], 0) & 0x1)
1193                                     cond = 1;
1194                                 break;
1195                         case bc1nez_op:
1196                                 if (!(get_fpr32(&current->thread.fpu.fpr[MIPSInst_RT(ir)], 0) & 0x1))
1197                                     cond = 1;
1198                                 break;
1199                         }
1200                         goto branch_common;
1201
1202                 case bc_op:
1203                         if (delay_slot(xcp))
1204                                 return SIGILL;
1205
1206                         if (cpu_has_mips_4_5_r)
1207                                 cbit = fpucondbit[MIPSInst_RT(ir) >> 2];
1208                         else
1209                                 cbit = FPU_CSR_COND;
1210                         cond = ctx->fcr31 & cbit;
1211
1212                         likely = 0;
1213                         switch (MIPSInst_RT(ir) & 3) {
1214                         case bcfl_op:
1215                                 if (cpu_has_mips_2_3_4_5_r)
1216                                         likely = 1;
1217                                 /* Fall through */
1218                         case bcf_op:
1219                                 cond = !cond;
1220                                 break;
1221                         case bctl_op:
1222                                 if (cpu_has_mips_2_3_4_5_r)
1223                                         likely = 1;
1224                                 /* Fall through */
1225                         case bct_op:
1226                                 break;
1227                         }
1228 branch_common:
1229                         set_delay_slot(xcp);
1230                         if (cond) {
1231                                 /*
1232                                  * Branch taken: emulate dslot instruction
1233                                  */
1234                                 unsigned long bcpc;
1235
1236                                 /*
1237                                  * Remember EPC at the branch to point back
1238                                  * at so that any delay-slot instruction
1239                                  * signal is not silently ignored.
1240                                  */
1241                                 bcpc = xcp->cp0_epc;
1242                                 xcp->cp0_epc += dec_insn.pc_inc;
1243
1244                                 contpc = MIPSInst_SIMM(ir);
1245                                 ir = dec_insn.next_insn;
1246                                 if (dec_insn.micro_mips_mode) {
1247                                         contpc = (xcp->cp0_epc + (contpc << 1));
1248
1249                                         /* If 16-bit instruction, not FPU. */
1250                                         if ((dec_insn.next_pc_inc == 2) ||
1251                                                 (microMIPS32_to_MIPS32((union mips_instruction *)&ir) == SIGILL)) {
1252
1253                                                 /*
1254                                                  * Since this instruction will
1255                                                  * be put on the stack with
1256                                                  * 32-bit words, get around
1257                                                  * this problem by putting a
1258                                                  * NOP16 as the second one.
1259                                                  */
1260                                                 if (dec_insn.next_pc_inc == 2)
1261                                                         ir = (ir & (~0xffff)) | MM_NOP16;
1262
1263                                                 /*
1264                                                  * Single step the non-CP1
1265                                                  * instruction in the dslot.
1266                                                  */
1267                                                 sig = mips_dsemul(xcp, ir,
1268                                                                   contpc);
1269                                                 if (sig)
1270                                                         xcp->cp0_epc = bcpc;
1271                                                 /*
1272                                                  * SIGILL forces out of
1273                                                  * the emulation loop.
1274                                                  */
1275                                                 return sig ? sig : SIGILL;
1276                                         }
1277                                 } else
1278                                         contpc = (xcp->cp0_epc + (contpc << 2));
1279
1280                                 switch (MIPSInst_OPCODE(ir)) {
1281                                 case lwc1_op:
1282                                 case swc1_op:
1283                                         goto emul;
1284
1285                                 case ldc1_op:
1286                                 case sdc1_op:
1287                                         if (cpu_has_mips_2_3_4_5_r)
1288                                                 goto emul;
1289
1290                                         goto bc_sigill;
1291
1292                                 case cop1_op:
1293                                         goto emul;
1294
1295                                 case cop1x_op:
1296                                         if (cpu_has_mips_4_5_64_r2_r6)
1297                                                 /* its one of ours */
1298                                                 goto emul;
1299
1300                                         goto bc_sigill;
1301
1302                                 case spec_op:
1303                                         switch (MIPSInst_FUNC(ir)) {
1304                                         case movc_op:
1305                                                 if (cpu_has_mips_4_5_r)
1306                                                         goto emul;
1307
1308                                                 goto bc_sigill;
1309                                         }
1310                                         break;
1311
1312                                 bc_sigill:
1313                                         xcp->cp0_epc = bcpc;
1314                                         return SIGILL;
1315                                 }
1316
1317                                 /*
1318                                  * Single step the non-cp1
1319                                  * instruction in the dslot
1320                                  */
1321                                 sig = mips_dsemul(xcp, ir, contpc);
1322                                 if (sig)
1323                                         xcp->cp0_epc = bcpc;
1324                                 /* SIGILL forces out of the emulation loop.  */
1325                                 return sig ? sig : SIGILL;
1326                         } else if (likely) {    /* branch not taken */
1327                                 /*
1328                                  * branch likely nullifies
1329                                  * dslot if not taken
1330                                  */
1331                                 xcp->cp0_epc += dec_insn.pc_inc;
1332                                 contpc += dec_insn.pc_inc;
1333                                 /*
1334                                  * else continue & execute
1335                                  * dslot as normal insn
1336                                  */
1337                         }
1338                         break;
1339
1340                 default:
1341                         if (!(MIPSInst_RS(ir) & 0x10))
1342                                 return SIGILL;
1343
1344                         /* a real fpu computation instruction */
1345                         if ((sig = fpu_emu(xcp, ctx, ir)))
1346                                 return sig;
1347                 }
1348                 break;
1349
1350         case cop1x_op:
1351                 if (!cpu_has_mips_4_5_64_r2_r6)
1352                         return SIGILL;
1353
1354                 sig = fpux_emu(xcp, ctx, ir, fault_addr);
1355                 if (sig)
1356                         return sig;
1357                 break;
1358
1359         case spec_op:
1360                 if (!cpu_has_mips_4_5_r)
1361                         return SIGILL;
1362
1363                 if (MIPSInst_FUNC(ir) != movc_op)
1364                         return SIGILL;
1365                 cond = fpucondbit[MIPSInst_RT(ir) >> 2];
1366                 if (((ctx->fcr31 & cond) != 0) == ((MIPSInst_RT(ir) & 1) != 0))
1367                         xcp->regs[MIPSInst_RD(ir)] =
1368                                 xcp->regs[MIPSInst_RS(ir)];
1369                 break;
1370         default:
1371 sigill:
1372                 return SIGILL;
1373         }
1374
1375         /* we did it !! */
1376         xcp->cp0_epc = contpc;
1377         clear_delay_slot(xcp);
1378
1379         return 0;
1380 }
1381
1382 /*
1383  * Conversion table from MIPS compare ops 48-63
1384  * cond = ieee754dp_cmp(x,y,IEEE754_UN,sig);
1385  */
1386 static const unsigned char cmptab[8] = {
1387         0,                      /* cmp_0 (sig) cmp_sf */
1388         IEEE754_CUN,            /* cmp_un (sig) cmp_ngle */
1389         IEEE754_CEQ,            /* cmp_eq (sig) cmp_seq */
1390         IEEE754_CEQ | IEEE754_CUN,      /* cmp_ueq (sig) cmp_ngl  */
1391         IEEE754_CLT,            /* cmp_olt (sig) cmp_lt */
1392         IEEE754_CLT | IEEE754_CUN,      /* cmp_ult (sig) cmp_nge */
1393         IEEE754_CLT | IEEE754_CEQ,      /* cmp_ole (sig) cmp_le */
1394         IEEE754_CLT | IEEE754_CEQ | IEEE754_CUN,        /* cmp_ule (sig) cmp_ngt */
1395 };
1396
1397 static const unsigned char negative_cmptab[8] = {
1398         0, /* Reserved */
1399         IEEE754_CLT | IEEE754_CGT | IEEE754_CEQ,
1400         IEEE754_CLT | IEEE754_CGT | IEEE754_CUN,
1401         IEEE754_CLT | IEEE754_CGT,
1402         /* Reserved */
1403 };
1404
1405
1406 /*
1407  * Additional MIPS4 instructions
1408  */
1409
1410 #define DEF3OP(name, p, f1, f2, f3)                                     \
1411 static union ieee754##p fpemu_##p##_##name(union ieee754##p r,          \
1412         union ieee754##p s, union ieee754##p t)                         \
1413 {                                                                       \
1414         struct _ieee754_csr ieee754_csr_save;                           \
1415         s = f1(s, t);                                                   \
1416         ieee754_csr_save = ieee754_csr;                                 \
1417         s = f2(s, r);                                                   \
1418         ieee754_csr_save.cx |= ieee754_csr.cx;                          \
1419         ieee754_csr_save.sx |= ieee754_csr.sx;                          \
1420         s = f3(s);                                                      \
1421         ieee754_csr.cx |= ieee754_csr_save.cx;                          \
1422         ieee754_csr.sx |= ieee754_csr_save.sx;                          \
1423         return s;                                                       \
1424 }
1425
1426 static union ieee754dp fpemu_dp_recip(union ieee754dp d)
1427 {
1428         return ieee754dp_div(ieee754dp_one(0), d);
1429 }
1430
1431 static union ieee754dp fpemu_dp_rsqrt(union ieee754dp d)
1432 {
1433         return ieee754dp_div(ieee754dp_one(0), ieee754dp_sqrt(d));
1434 }
1435
1436 static union ieee754sp fpemu_sp_recip(union ieee754sp s)
1437 {
1438         return ieee754sp_div(ieee754sp_one(0), s);
1439 }
1440
1441 static union ieee754sp fpemu_sp_rsqrt(union ieee754sp s)
1442 {
1443         return ieee754sp_div(ieee754sp_one(0), ieee754sp_sqrt(s));
1444 }
1445
1446 DEF3OP(madd, sp, ieee754sp_mul, ieee754sp_add, );
1447 DEF3OP(msub, sp, ieee754sp_mul, ieee754sp_sub, );
1448 DEF3OP(nmadd, sp, ieee754sp_mul, ieee754sp_add, ieee754sp_neg);
1449 DEF3OP(nmsub, sp, ieee754sp_mul, ieee754sp_sub, ieee754sp_neg);
1450 DEF3OP(madd, dp, ieee754dp_mul, ieee754dp_add, );
1451 DEF3OP(msub, dp, ieee754dp_mul, ieee754dp_sub, );
1452 DEF3OP(nmadd, dp, ieee754dp_mul, ieee754dp_add, ieee754dp_neg);
1453 DEF3OP(nmsub, dp, ieee754dp_mul, ieee754dp_sub, ieee754dp_neg);
1454
1455 static int fpux_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
1456         mips_instruction ir, void *__user *fault_addr)
1457 {
1458         unsigned rcsr = 0;      /* resulting csr */
1459
1460         MIPS_FPU_EMU_INC_STATS(cp1xops);
1461
1462         switch (MIPSInst_FMA_FFMT(ir)) {
1463         case s_fmt:{            /* 0 */
1464
1465                 union ieee754sp(*handler) (union ieee754sp, union ieee754sp, union ieee754sp);
1466                 union ieee754sp fd, fr, fs, ft;
1467                 u32 __user *va;
1468                 u32 val;
1469
1470                 switch (MIPSInst_FUNC(ir)) {
1471                 case lwxc1_op:
1472                         va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1473                                 xcp->regs[MIPSInst_FT(ir)]);
1474
1475                         MIPS_FPU_EMU_INC_STATS(loads);
1476                         if (!access_ok(VERIFY_READ, va, sizeof(u32))) {
1477                                 MIPS_FPU_EMU_INC_STATS(errors);
1478                                 *fault_addr = va;
1479                                 return SIGBUS;
1480                         }
1481                         if (__get_user(val, va)) {
1482                                 MIPS_FPU_EMU_INC_STATS(errors);
1483                                 *fault_addr = va;
1484                                 return SIGSEGV;
1485                         }
1486                         SITOREG(val, MIPSInst_FD(ir));
1487                         break;
1488
1489                 case swxc1_op:
1490                         va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1491                                 xcp->regs[MIPSInst_FT(ir)]);
1492
1493                         MIPS_FPU_EMU_INC_STATS(stores);
1494
1495                         SIFROMREG(val, MIPSInst_FS(ir));
1496                         if (!access_ok(VERIFY_WRITE, va, sizeof(u32))) {
1497                                 MIPS_FPU_EMU_INC_STATS(errors);
1498                                 *fault_addr = va;
1499                                 return SIGBUS;
1500                         }
1501                         if (put_user(val, va)) {
1502                                 MIPS_FPU_EMU_INC_STATS(errors);
1503                                 *fault_addr = va;
1504                                 return SIGSEGV;
1505                         }
1506                         break;
1507
1508                 case madd_s_op:
1509                         handler = fpemu_sp_madd;
1510                         goto scoptop;
1511                 case msub_s_op:
1512                         handler = fpemu_sp_msub;
1513                         goto scoptop;
1514                 case nmadd_s_op:
1515                         handler = fpemu_sp_nmadd;
1516                         goto scoptop;
1517                 case nmsub_s_op:
1518                         handler = fpemu_sp_nmsub;
1519                         goto scoptop;
1520
1521                       scoptop:
1522                         SPFROMREG(fr, MIPSInst_FR(ir));
1523                         SPFROMREG(fs, MIPSInst_FS(ir));
1524                         SPFROMREG(ft, MIPSInst_FT(ir));
1525                         fd = (*handler) (fr, fs, ft);
1526                         SPTOREG(fd, MIPSInst_FD(ir));
1527
1528                       copcsr:
1529                         if (ieee754_cxtest(IEEE754_INEXACT)) {
1530                                 MIPS_FPU_EMU_INC_STATS(ieee754_inexact);
1531                                 rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
1532                         }
1533                         if (ieee754_cxtest(IEEE754_UNDERFLOW)) {
1534                                 MIPS_FPU_EMU_INC_STATS(ieee754_underflow);
1535                                 rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
1536                         }
1537                         if (ieee754_cxtest(IEEE754_OVERFLOW)) {
1538                                 MIPS_FPU_EMU_INC_STATS(ieee754_overflow);
1539                                 rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
1540                         }
1541                         if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) {
1542                                 MIPS_FPU_EMU_INC_STATS(ieee754_invalidop);
1543                                 rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
1544                         }
1545
1546                         ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
1547                         if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
1548                                 /*printk ("SIGFPE: FPU csr = %08x\n",
1549                                    ctx->fcr31); */
1550                                 return SIGFPE;
1551                         }
1552
1553                         break;
1554
1555                 default:
1556                         return SIGILL;
1557                 }
1558                 break;
1559         }
1560
1561         case d_fmt:{            /* 1 */
1562                 union ieee754dp(*handler) (union ieee754dp, union ieee754dp, union ieee754dp);
1563                 union ieee754dp fd, fr, fs, ft;
1564                 u64 __user *va;
1565                 u64 val;
1566
1567                 switch (MIPSInst_FUNC(ir)) {
1568                 case ldxc1_op:
1569                         va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1570                                 xcp->regs[MIPSInst_FT(ir)]);
1571
1572                         MIPS_FPU_EMU_INC_STATS(loads);
1573                         if (!access_ok(VERIFY_READ, va, sizeof(u64))) {
1574                                 MIPS_FPU_EMU_INC_STATS(errors);
1575                                 *fault_addr = va;
1576                                 return SIGBUS;
1577                         }
1578                         if (__get_user(val, va)) {
1579                                 MIPS_FPU_EMU_INC_STATS(errors);
1580                                 *fault_addr = va;
1581                                 return SIGSEGV;
1582                         }
1583                         DITOREG(val, MIPSInst_FD(ir));
1584                         break;
1585
1586                 case sdxc1_op:
1587                         va = (void __user *) (xcp->regs[MIPSInst_FR(ir)] +
1588                                 xcp->regs[MIPSInst_FT(ir)]);
1589
1590                         MIPS_FPU_EMU_INC_STATS(stores);
1591                         DIFROMREG(val, MIPSInst_FS(ir));
1592                         if (!access_ok(VERIFY_WRITE, va, sizeof(u64))) {
1593                                 MIPS_FPU_EMU_INC_STATS(errors);
1594                                 *fault_addr = va;
1595                                 return SIGBUS;
1596                         }
1597                         if (__put_user(val, va)) {
1598                                 MIPS_FPU_EMU_INC_STATS(errors);
1599                                 *fault_addr = va;
1600                                 return SIGSEGV;
1601                         }
1602                         break;
1603
1604                 case madd_d_op:
1605                         handler = fpemu_dp_madd;
1606                         goto dcoptop;
1607                 case msub_d_op:
1608                         handler = fpemu_dp_msub;
1609                         goto dcoptop;
1610                 case nmadd_d_op:
1611                         handler = fpemu_dp_nmadd;
1612                         goto dcoptop;
1613                 case nmsub_d_op:
1614                         handler = fpemu_dp_nmsub;
1615                         goto dcoptop;
1616
1617                       dcoptop:
1618                         DPFROMREG(fr, MIPSInst_FR(ir));
1619                         DPFROMREG(fs, MIPSInst_FS(ir));
1620                         DPFROMREG(ft, MIPSInst_FT(ir));
1621                         fd = (*handler) (fr, fs, ft);
1622                         DPTOREG(fd, MIPSInst_FD(ir));
1623                         goto copcsr;
1624
1625                 default:
1626                         return SIGILL;
1627                 }
1628                 break;
1629         }
1630
1631         case 0x3:
1632                 if (MIPSInst_FUNC(ir) != pfetch_op)
1633                         return SIGILL;
1634
1635                 /* ignore prefx operation */
1636                 break;
1637
1638         default:
1639                 return SIGILL;
1640         }
1641
1642         return 0;
1643 }
1644
1645
1646
1647 /*
1648  * Emulate a single COP1 arithmetic instruction.
1649  */
1650 static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
1651         mips_instruction ir)
1652 {
1653         int rfmt;               /* resulting format */
1654         unsigned rcsr = 0;      /* resulting csr */
1655         unsigned int oldrm;
1656         unsigned int cbit;
1657         unsigned cond;
1658         union {
1659                 union ieee754dp d;
1660                 union ieee754sp s;
1661                 int w;
1662                 s64 l;
1663         } rv;                   /* resulting value */
1664         u64 bits;
1665
1666         MIPS_FPU_EMU_INC_STATS(cp1ops);
1667         switch (rfmt = (MIPSInst_FFMT(ir) & 0xf)) {
1668         case s_fmt: {           /* 0 */
1669                 union {
1670                         union ieee754sp(*b) (union ieee754sp, union ieee754sp);
1671                         union ieee754sp(*u) (union ieee754sp);
1672                 } handler;
1673                 union ieee754sp fs, ft;
1674
1675                 switch (MIPSInst_FUNC(ir)) {
1676                         /* binary ops */
1677                 case fadd_op:
1678                         handler.b = ieee754sp_add;
1679                         goto scopbop;
1680                 case fsub_op:
1681                         handler.b = ieee754sp_sub;
1682                         goto scopbop;
1683                 case fmul_op:
1684                         handler.b = ieee754sp_mul;
1685                         goto scopbop;
1686                 case fdiv_op:
1687                         handler.b = ieee754sp_div;
1688                         goto scopbop;
1689
1690                         /* unary  ops */
1691                 case fsqrt_op:
1692                         if (!cpu_has_mips_2_3_4_5_r)
1693                                 return SIGILL;
1694
1695                         handler.u = ieee754sp_sqrt;
1696                         goto scopuop;
1697
1698                 /*
1699                  * Note that on some MIPS IV implementations such as the
1700                  * R5000 and R8000 the FSQRT and FRECIP instructions do not
1701                  * achieve full IEEE-754 accuracy - however this emulator does.
1702                  */
1703                 case frsqrt_op:
1704                         if (!cpu_has_mips_4_5_64_r2_r6)
1705                                 return SIGILL;
1706
1707                         handler.u = fpemu_sp_rsqrt;
1708                         goto scopuop;
1709
1710                 case frecip_op:
1711                         if (!cpu_has_mips_4_5_64_r2_r6)
1712                                 return SIGILL;
1713
1714                         handler.u = fpemu_sp_recip;
1715                         goto scopuop;
1716
1717                 case fmovc_op:
1718                         if (!cpu_has_mips_4_5_r)
1719                                 return SIGILL;
1720
1721                         cond = fpucondbit[MIPSInst_FT(ir) >> 2];
1722                         if (((ctx->fcr31 & cond) != 0) !=
1723                                 ((MIPSInst_FT(ir) & 1) != 0))
1724                                 return 0;
1725                         SPFROMREG(rv.s, MIPSInst_FS(ir));
1726                         break;
1727
1728                 case fmovz_op:
1729                         if (!cpu_has_mips_4_5_r)
1730                                 return SIGILL;
1731
1732                         if (xcp->regs[MIPSInst_FT(ir)] != 0)
1733                                 return 0;
1734                         SPFROMREG(rv.s, MIPSInst_FS(ir));
1735                         break;
1736
1737                 case fmovn_op:
1738                         if (!cpu_has_mips_4_5_r)
1739                                 return SIGILL;
1740
1741                         if (xcp->regs[MIPSInst_FT(ir)] == 0)
1742                                 return 0;
1743                         SPFROMREG(rv.s, MIPSInst_FS(ir));
1744                         break;
1745
1746                 case fseleqz_op:
1747                         if (!cpu_has_mips_r6)
1748                                 return SIGILL;
1749
1750                         SPFROMREG(rv.s, MIPSInst_FT(ir));
1751                         if (rv.w & 0x1)
1752                                 rv.w = 0;
1753                         else
1754                                 SPFROMREG(rv.s, MIPSInst_FS(ir));
1755                         break;
1756
1757                 case fselnez_op:
1758                         if (!cpu_has_mips_r6)
1759                                 return SIGILL;
1760
1761                         SPFROMREG(rv.s, MIPSInst_FT(ir));
1762                         if (rv.w & 0x1)
1763                                 SPFROMREG(rv.s, MIPSInst_FS(ir));
1764                         else
1765                                 rv.w = 0;
1766                         break;
1767
1768                 case fmaddf_op: {
1769                         union ieee754sp ft, fs, fd;
1770
1771                         if (!cpu_has_mips_r6)
1772                                 return SIGILL;
1773
1774                         SPFROMREG(ft, MIPSInst_FT(ir));
1775                         SPFROMREG(fs, MIPSInst_FS(ir));
1776                         SPFROMREG(fd, MIPSInst_FD(ir));
1777                         rv.s = ieee754sp_maddf(fd, fs, ft);
1778                         break;
1779                 }
1780
1781                 case fmsubf_op: {
1782                         union ieee754sp ft, fs, fd;
1783
1784                         if (!cpu_has_mips_r6)
1785                                 return SIGILL;
1786
1787                         SPFROMREG(ft, MIPSInst_FT(ir));
1788                         SPFROMREG(fs, MIPSInst_FS(ir));
1789                         SPFROMREG(fd, MIPSInst_FD(ir));
1790                         rv.s = ieee754sp_msubf(fd, fs, ft);
1791                         break;
1792                 }
1793
1794                 case frint_op: {
1795                         union ieee754sp fs;
1796
1797                         if (!cpu_has_mips_r6)
1798                                 return SIGILL;
1799
1800                         SPFROMREG(fs, MIPSInst_FS(ir));
1801                         rv.l = ieee754sp_tlong(fs);
1802                         rv.s = ieee754sp_flong(rv.l);
1803                         goto copcsr;
1804                 }
1805
1806                 case fclass_op: {
1807                         union ieee754sp fs;
1808
1809                         if (!cpu_has_mips_r6)
1810                                 return SIGILL;
1811
1812                         SPFROMREG(fs, MIPSInst_FS(ir));
1813                         rv.w = ieee754sp_2008class(fs);
1814                         rfmt = w_fmt;
1815                         break;
1816                 }
1817
1818                 case fabs_op:
1819                         handler.u = ieee754sp_abs;
1820                         goto scopuop;
1821
1822                 case fneg_op:
1823                         handler.u = ieee754sp_neg;
1824                         goto scopuop;
1825
1826                 case fmov_op:
1827                         /* an easy one */
1828                         SPFROMREG(rv.s, MIPSInst_FS(ir));
1829                         goto copcsr;
1830
1831                         /* binary op on handler */
1832 scopbop:
1833                         SPFROMREG(fs, MIPSInst_FS(ir));
1834                         SPFROMREG(ft, MIPSInst_FT(ir));
1835
1836                         rv.s = (*handler.b) (fs, ft);
1837                         goto copcsr;
1838 scopuop:
1839                         SPFROMREG(fs, MIPSInst_FS(ir));
1840                         rv.s = (*handler.u) (fs);
1841                         goto copcsr;
1842 copcsr:
1843                         if (ieee754_cxtest(IEEE754_INEXACT)) {
1844                                 MIPS_FPU_EMU_INC_STATS(ieee754_inexact);
1845                                 rcsr |= FPU_CSR_INE_X | FPU_CSR_INE_S;
1846                         }
1847                         if (ieee754_cxtest(IEEE754_UNDERFLOW)) {
1848                                 MIPS_FPU_EMU_INC_STATS(ieee754_underflow);
1849                                 rcsr |= FPU_CSR_UDF_X | FPU_CSR_UDF_S;
1850                         }
1851                         if (ieee754_cxtest(IEEE754_OVERFLOW)) {
1852                                 MIPS_FPU_EMU_INC_STATS(ieee754_overflow);
1853                                 rcsr |= FPU_CSR_OVF_X | FPU_CSR_OVF_S;
1854                         }
1855                         if (ieee754_cxtest(IEEE754_ZERO_DIVIDE)) {
1856                                 MIPS_FPU_EMU_INC_STATS(ieee754_zerodiv);
1857                                 rcsr |= FPU_CSR_DIV_X | FPU_CSR_DIV_S;
1858                         }
1859                         if (ieee754_cxtest(IEEE754_INVALID_OPERATION)) {
1860                                 MIPS_FPU_EMU_INC_STATS(ieee754_invalidop);
1861                                 rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S;
1862                         }
1863                         break;
1864
1865                         /* unary conv ops */
1866                 case fcvts_op:
1867                         return SIGILL;  /* not defined */
1868
1869                 case fcvtd_op:
1870                         SPFROMREG(fs, MIPSInst_FS(ir));
1871                         rv.d = ieee754dp_fsp(fs);
1872                         rfmt = d_fmt;
1873                         goto copcsr;
1874
1875                 case fcvtw_op:
1876                         SPFROMREG(fs, MIPSInst_FS(ir));
1877                         rv.w = ieee754sp_tint(fs);
1878                         rfmt = w_fmt;
1879                         goto copcsr;
1880
1881                 case fround_op:
1882                 case ftrunc_op:
1883                 case fceil_op:
1884                 case ffloor_op:
1885                         if (!cpu_has_mips_2_3_4_5_r)
1886                                 return SIGILL;
1887
1888                         oldrm = ieee754_csr.rm;
1889                         SPFROMREG(fs, MIPSInst_FS(ir));
1890                         ieee754_csr.rm = MIPSInst_FUNC(ir);
1891                         rv.w = ieee754sp_tint(fs);
1892                         ieee754_csr.rm = oldrm;
1893                         rfmt = w_fmt;
1894                         goto copcsr;
1895
1896                 case fcvtl_op:
1897                         if (!cpu_has_mips_3_4_5_64_r2_r6)
1898                                 return SIGILL;
1899
1900                         SPFROMREG(fs, MIPSInst_FS(ir));
1901                         rv.l = ieee754sp_tlong(fs);
1902                         rfmt = l_fmt;
1903                         goto copcsr;
1904
1905                 case froundl_op:
1906                 case ftruncl_op:
1907                 case fceill_op:
1908                 case ffloorl_op:
1909                         if (!cpu_has_mips_3_4_5_64_r2_r6)
1910                                 return SIGILL;
1911
1912                         oldrm = ieee754_csr.rm;
1913                         SPFROMREG(fs, MIPSInst_FS(ir));
1914                         ieee754_csr.rm = MIPSInst_FUNC(ir);
1915                         rv.l = ieee754sp_tlong(fs);
1916                         ieee754_csr.rm = oldrm;
1917                         rfmt = l_fmt;
1918                         goto copcsr;
1919
1920                 default:
1921                         if (!NO_R6EMU && MIPSInst_FUNC(ir) >= fcmp_op) {
1922                                 unsigned cmpop = MIPSInst_FUNC(ir) - fcmp_op;
1923                                 union ieee754sp fs, ft;
1924
1925                                 SPFROMREG(fs, MIPSInst_FS(ir));
1926                                 SPFROMREG(ft, MIPSInst_FT(ir));
1927                                 rv.w = ieee754sp_cmp(fs, ft,
1928                                         cmptab[cmpop & 0x7], cmpop & 0x8);
1929                                 rfmt = -1;
1930                                 if ((cmpop & 0x8) && ieee754_cxtest
1931                                         (IEEE754_INVALID_OPERATION))
1932                                         rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
1933                                 else
1934                                         goto copcsr;
1935
1936                         } else
1937                                 return SIGILL;
1938                         break;
1939                 }
1940                 break;
1941         }
1942
1943         case d_fmt: {
1944                 union ieee754dp fs, ft;
1945                 union {
1946                         union ieee754dp(*b) (union ieee754dp, union ieee754dp);
1947                         union ieee754dp(*u) (union ieee754dp);
1948                 } handler;
1949
1950                 switch (MIPSInst_FUNC(ir)) {
1951                         /* binary ops */
1952                 case fadd_op:
1953                         handler.b = ieee754dp_add;
1954                         goto dcopbop;
1955                 case fsub_op:
1956                         handler.b = ieee754dp_sub;
1957                         goto dcopbop;
1958                 case fmul_op:
1959                         handler.b = ieee754dp_mul;
1960                         goto dcopbop;
1961                 case fdiv_op:
1962                         handler.b = ieee754dp_div;
1963                         goto dcopbop;
1964
1965                         /* unary  ops */
1966                 case fsqrt_op:
1967                         if (!cpu_has_mips_2_3_4_5_r)
1968                                 return SIGILL;
1969
1970                         handler.u = ieee754dp_sqrt;
1971                         goto dcopuop;
1972                 /*
1973                  * Note that on some MIPS IV implementations such as the
1974                  * R5000 and R8000 the FSQRT and FRECIP instructions do not
1975                  * achieve full IEEE-754 accuracy - however this emulator does.
1976                  */
1977                 case frsqrt_op:
1978                         if (!cpu_has_mips_4_5_64_r2_r6)
1979                                 return SIGILL;
1980
1981                         handler.u = fpemu_dp_rsqrt;
1982                         goto dcopuop;
1983                 case frecip_op:
1984                         if (!cpu_has_mips_4_5_64_r2_r6)
1985                                 return SIGILL;
1986
1987                         handler.u = fpemu_dp_recip;
1988                         goto dcopuop;
1989                 case fmovc_op:
1990                         if (!cpu_has_mips_4_5_r)
1991                                 return SIGILL;
1992
1993                         cond = fpucondbit[MIPSInst_FT(ir) >> 2];
1994                         if (((ctx->fcr31 & cond) != 0) !=
1995                                 ((MIPSInst_FT(ir) & 1) != 0))
1996                                 return 0;
1997                         DPFROMREG(rv.d, MIPSInst_FS(ir));
1998                         break;
1999                 case fmovz_op:
2000                         if (!cpu_has_mips_4_5_r)
2001                                 return SIGILL;
2002
2003                         if (xcp->regs[MIPSInst_FT(ir)] != 0)
2004                                 return 0;
2005                         DPFROMREG(rv.d, MIPSInst_FS(ir));
2006                         break;
2007                 case fmovn_op:
2008                         if (!cpu_has_mips_4_5_r)
2009                                 return SIGILL;
2010
2011                         if (xcp->regs[MIPSInst_FT(ir)] == 0)
2012                                 return 0;
2013                         DPFROMREG(rv.d, MIPSInst_FS(ir));
2014                         break;
2015
2016                 case fseleqz_op:
2017                         if (!cpu_has_mips_r6)
2018                                 return SIGILL;
2019
2020                         DPFROMREG(rv.d, MIPSInst_FT(ir));
2021                         if (rv.l & 0x1)
2022                                 rv.l = 0;
2023                         else
2024                                 DPFROMREG(rv.d, MIPSInst_FS(ir));
2025                         break;
2026
2027                 case fselnez_op:
2028                         if (!cpu_has_mips_r6)
2029                                 return SIGILL;
2030
2031                         DPFROMREG(rv.d, MIPSInst_FT(ir));
2032                         if (rv.l & 0x1)
2033                                 DPFROMREG(rv.d, MIPSInst_FS(ir));
2034                         else
2035                                 rv.l = 0;
2036                         break;
2037
2038                 case fmaddf_op: {
2039                         union ieee754dp ft, fs, fd;
2040
2041                         if (!cpu_has_mips_r6)
2042                                 return SIGILL;
2043
2044                         DPFROMREG(ft, MIPSInst_FT(ir));
2045                         DPFROMREG(fs, MIPSInst_FS(ir));
2046                         DPFROMREG(fd, MIPSInst_FD(ir));
2047                         rv.d = ieee754dp_maddf(fd, fs, ft);
2048                         break;
2049                 }
2050
2051                 case fmsubf_op: {
2052                         union ieee754dp ft, fs, fd;
2053
2054                         if (!cpu_has_mips_r6)
2055                                 return SIGILL;
2056
2057                         DPFROMREG(ft, MIPSInst_FT(ir));
2058                         DPFROMREG(fs, MIPSInst_FS(ir));
2059                         DPFROMREG(fd, MIPSInst_FD(ir));
2060                         rv.d = ieee754dp_msubf(fd, fs, ft);
2061                         break;
2062                 }
2063
2064                 case frint_op: {
2065                         union ieee754dp fs;
2066
2067                         if (!cpu_has_mips_r6)
2068                                 return SIGILL;
2069
2070                         DPFROMREG(fs, MIPSInst_FS(ir));
2071                         rv.l = ieee754dp_tlong(fs);
2072                         rv.d = ieee754dp_flong(rv.l);
2073                         goto copcsr;
2074                 }
2075
2076                 case fclass_op: {
2077                         union ieee754dp fs;
2078
2079                         if (!cpu_has_mips_r6)
2080                                 return SIGILL;
2081
2082                         DPFROMREG(fs, MIPSInst_FS(ir));
2083                         rv.w = ieee754dp_2008class(fs);
2084                         rfmt = w_fmt;
2085                         break;
2086                 }
2087
2088                 case fabs_op:
2089                         handler.u = ieee754dp_abs;
2090                         goto dcopuop;
2091
2092                 case fneg_op:
2093                         handler.u = ieee754dp_neg;
2094                         goto dcopuop;
2095
2096                 case fmov_op:
2097                         /* an easy one */
2098                         DPFROMREG(rv.d, MIPSInst_FS(ir));
2099                         goto copcsr;
2100
2101                         /* binary op on handler */
2102 dcopbop:
2103                         DPFROMREG(fs, MIPSInst_FS(ir));
2104                         DPFROMREG(ft, MIPSInst_FT(ir));
2105
2106                         rv.d = (*handler.b) (fs, ft);
2107                         goto copcsr;
2108 dcopuop:
2109                         DPFROMREG(fs, MIPSInst_FS(ir));
2110                         rv.d = (*handler.u) (fs);
2111                         goto copcsr;
2112
2113                 /*
2114                  * unary conv ops
2115                  */
2116                 case fcvts_op:
2117                         DPFROMREG(fs, MIPSInst_FS(ir));
2118                         rv.s = ieee754sp_fdp(fs);
2119                         rfmt = s_fmt;
2120                         goto copcsr;
2121
2122                 case fcvtd_op:
2123                         return SIGILL;  /* not defined */
2124
2125                 case fcvtw_op:
2126                         DPFROMREG(fs, MIPSInst_FS(ir));
2127                         rv.w = ieee754dp_tint(fs);      /* wrong */
2128                         rfmt = w_fmt;
2129                         goto copcsr;
2130
2131                 case fround_op:
2132                 case ftrunc_op:
2133                 case fceil_op:
2134                 case ffloor_op:
2135                         if (!cpu_has_mips_2_3_4_5_r)
2136                                 return SIGILL;
2137
2138                         oldrm = ieee754_csr.rm;
2139                         DPFROMREG(fs, MIPSInst_FS(ir));
2140                         ieee754_csr.rm = MIPSInst_FUNC(ir);
2141                         rv.w = ieee754dp_tint(fs);
2142                         ieee754_csr.rm = oldrm;
2143                         rfmt = w_fmt;
2144                         goto copcsr;
2145
2146                 case fcvtl_op:
2147                         if (!cpu_has_mips_3_4_5_64_r2_r6)
2148                                 return SIGILL;
2149
2150                         DPFROMREG(fs, MIPSInst_FS(ir));
2151                         rv.l = ieee754dp_tlong(fs);
2152                         rfmt = l_fmt;
2153                         goto copcsr;
2154
2155                 case froundl_op:
2156                 case ftruncl_op:
2157                 case fceill_op:
2158                 case ffloorl_op:
2159                         if (!cpu_has_mips_3_4_5_64_r2_r6)
2160                                 return SIGILL;
2161
2162                         oldrm = ieee754_csr.rm;
2163                         DPFROMREG(fs, MIPSInst_FS(ir));
2164                         ieee754_csr.rm = MIPSInst_FUNC(ir);
2165                         rv.l = ieee754dp_tlong(fs);
2166                         ieee754_csr.rm = oldrm;
2167                         rfmt = l_fmt;
2168                         goto copcsr;
2169
2170                 default:
2171                         if (!NO_R6EMU && MIPSInst_FUNC(ir) >= fcmp_op) {
2172                                 unsigned cmpop = MIPSInst_FUNC(ir) - fcmp_op;
2173                                 union ieee754dp fs, ft;
2174
2175                                 DPFROMREG(fs, MIPSInst_FS(ir));
2176                                 DPFROMREG(ft, MIPSInst_FT(ir));
2177                                 rv.w = ieee754dp_cmp(fs, ft,
2178                                         cmptab[cmpop & 0x7], cmpop & 0x8);
2179                                 rfmt = -1;
2180                                 if ((cmpop & 0x8)
2181                                         &&
2182                                         ieee754_cxtest
2183                                         (IEEE754_INVALID_OPERATION))
2184                                         rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2185                                 else
2186                                         goto copcsr;
2187
2188                         }
2189                         else {
2190                                 return SIGILL;
2191                         }
2192                         break;
2193                 }
2194                 break;
2195         }
2196
2197         case w_fmt: {
2198                 union ieee754dp fs;
2199
2200                 switch (MIPSInst_FUNC(ir)) {
2201                 case fcvts_op:
2202                         /* convert word to single precision real */
2203                         SPFROMREG(fs, MIPSInst_FS(ir));
2204                         rv.s = ieee754sp_fint(fs.bits);
2205                         rfmt = s_fmt;
2206                         goto copcsr;
2207                 case fcvtd_op:
2208                         /* convert word to double precision real */
2209                         SPFROMREG(fs, MIPSInst_FS(ir));
2210                         rv.d = ieee754dp_fint(fs.bits);
2211                         rfmt = d_fmt;
2212                         goto copcsr;
2213                 default: {
2214                         /* Emulating the new CMP.condn.fmt R6 instruction */
2215 #define CMPOP_MASK      0x7
2216 #define SIGN_BIT        (0x1 << 3)
2217 #define PREDICATE_BIT   (0x1 << 4)
2218
2219                         int cmpop = MIPSInst_FUNC(ir) & CMPOP_MASK;
2220                         int sig = MIPSInst_FUNC(ir) & SIGN_BIT;
2221                         union ieee754sp fs, ft;
2222
2223                         /* This is an R6 only instruction */
2224                         if (!cpu_has_mips_r6 ||
2225                             (MIPSInst_FUNC(ir) & 0x20))
2226                                 return SIGILL;
2227
2228                         /* fmt is w_fmt for single precision so fix it */
2229                         rfmt = s_fmt;
2230                         /* default to false */
2231                         rv.w = 0;
2232
2233                         /* CMP.condn.S */
2234                         SPFROMREG(fs, MIPSInst_FS(ir));
2235                         SPFROMREG(ft, MIPSInst_FT(ir));
2236
2237                         /* positive predicates */
2238                         if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2239                                 if (ieee754sp_cmp(fs, ft, cmptab[cmpop],
2240                                                   sig))
2241                                     rv.w = -1; /* true, all 1s */
2242                                 if ((sig) &&
2243                                     ieee754_cxtest(IEEE754_INVALID_OPERATION))
2244                                         rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2245                                 else
2246                                         goto copcsr;
2247                         } else {
2248                                 /* negative predicates */
2249                                 switch (cmpop) {
2250                                 case 1:
2251                                 case 2:
2252                                 case 3:
2253                                         if (ieee754sp_cmp(fs, ft,
2254                                                           negative_cmptab[cmpop],
2255                                                           sig))
2256                                                 rv.w = -1; /* true, all 1s */
2257                                         if (sig &&
2258                                             ieee754_cxtest(IEEE754_INVALID_OPERATION))
2259                                                 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2260                                         else
2261                                                 goto copcsr;
2262                                         break;
2263                                 default:
2264                                         /* Reserved R6 ops */
2265                                         pr_err("Reserved MIPS R6 CMP.condn.S operation\n");
2266                                         return SIGILL;
2267                                 }
2268                         }
2269                         break;
2270                         }
2271                 }
2272         }
2273
2274         case l_fmt:
2275
2276                 if (!cpu_has_mips_3_4_5_64_r2_r6)
2277                         return SIGILL;
2278
2279                 DIFROMREG(bits, MIPSInst_FS(ir));
2280
2281                 switch (MIPSInst_FUNC(ir)) {
2282                 case fcvts_op:
2283                         /* convert long to single precision real */
2284                         rv.s = ieee754sp_flong(bits);
2285                         rfmt = s_fmt;
2286                         goto copcsr;
2287                 case fcvtd_op:
2288                         /* convert long to double precision real */
2289                         rv.d = ieee754dp_flong(bits);
2290                         rfmt = d_fmt;
2291                         goto copcsr;
2292                 default: {
2293                         /* Emulating the new CMP.condn.fmt R6 instruction */
2294                         int cmpop = MIPSInst_FUNC(ir) & CMPOP_MASK;
2295                         int sig = MIPSInst_FUNC(ir) & SIGN_BIT;
2296                         union ieee754dp fs, ft;
2297
2298                         if (!cpu_has_mips_r6 ||
2299                             (MIPSInst_FUNC(ir) & 0x20))
2300                                 return SIGILL;
2301
2302                         /* fmt is l_fmt for double precision so fix it */
2303                         rfmt = d_fmt;
2304                         /* default to false */
2305                         rv.l = 0;
2306
2307                         /* CMP.condn.D */
2308                         DPFROMREG(fs, MIPSInst_FS(ir));
2309                         DPFROMREG(ft, MIPSInst_FT(ir));
2310
2311                         /* positive predicates */
2312                         if (!(MIPSInst_FUNC(ir) & PREDICATE_BIT)) {
2313                                 if (ieee754dp_cmp(fs, ft,
2314                                                   cmptab[cmpop], sig))
2315                                     rv.l = -1LL; /* true, all 1s */
2316                                 if (sig &&
2317                                     ieee754_cxtest(IEEE754_INVALID_OPERATION))
2318                                         rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2319                                 else
2320                                         goto copcsr;
2321                         } else {
2322                                 /* negative predicates */
2323                                 switch (cmpop) {
2324                                 case 1:
2325                                 case 2:
2326                                 case 3:
2327                                         if (ieee754dp_cmp(fs, ft,
2328                                                           negative_cmptab[cmpop],
2329                                                           sig))
2330                                                 rv.l = -1LL; /* true, all 1s */
2331                                         if (sig &&
2332                                             ieee754_cxtest(IEEE754_INVALID_OPERATION))
2333                                                 rcsr = FPU_CSR_INV_X | FPU_CSR_INV_S;
2334                                         else
2335                                                 goto copcsr;
2336                                         break;
2337                                 default:
2338                                         /* Reserved R6 ops */
2339                                         pr_err("Reserved MIPS R6 CMP.condn.D operation\n");
2340                                         return SIGILL;
2341                                 }
2342                         }
2343                         break;
2344                         }
2345                 }
2346         default:
2347                 return SIGILL;
2348         }
2349
2350         /*
2351          * Update the fpu CSR register for this operation.
2352          * If an exception is required, generate a tidy SIGFPE exception,
2353          * without updating the result register.
2354          * Note: cause exception bits do not accumulate, they are rewritten
2355          * for each op; only the flag/sticky bits accumulate.
2356          */
2357         ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr;
2358         if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) {
2359                 /*printk ("SIGFPE: FPU csr = %08x\n",ctx->fcr31); */
2360                 return SIGFPE;
2361         }
2362
2363         /*
2364          * Now we can safely write the result back to the register file.
2365          */
2366         switch (rfmt) {
2367         case -1:
2368
2369                 if (cpu_has_mips_4_5_r)
2370                         cbit = fpucondbit[MIPSInst_FD(ir) >> 2];
2371                 else
2372                         cbit = FPU_CSR_COND;
2373                 if (rv.w)
2374                         ctx->fcr31 |= cbit;
2375                 else
2376                         ctx->fcr31 &= ~cbit;
2377                 break;
2378
2379         case d_fmt:
2380                 DPTOREG(rv.d, MIPSInst_FD(ir));
2381                 break;
2382         case s_fmt:
2383                 SPTOREG(rv.s, MIPSInst_FD(ir));
2384                 break;
2385         case w_fmt:
2386                 SITOREG(rv.w, MIPSInst_FD(ir));
2387                 break;
2388         case l_fmt:
2389                 if (!cpu_has_mips_3_4_5_64_r2_r6)
2390                         return SIGILL;
2391
2392                 DITOREG(rv.l, MIPSInst_FD(ir));
2393                 break;
2394         default:
2395                 return SIGILL;
2396         }
2397
2398         return 0;
2399 }
2400
2401 int fpu_emulator_cop1Handler(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
2402         int has_fpu, void *__user *fault_addr)
2403 {
2404         unsigned long oldepc, prevepc;
2405         struct mm_decoded_insn dec_insn;
2406         u16 instr[4];
2407         u16 *instr_ptr;
2408         int sig = 0;
2409
2410         oldepc = xcp->cp0_epc;
2411         do {
2412                 prevepc = xcp->cp0_epc;
2413
2414                 if (get_isa16_mode(prevepc) && cpu_has_mmips) {
2415                         /*
2416                          * Get next 2 microMIPS instructions and convert them
2417                          * into 32-bit instructions.
2418                          */
2419                         if ((get_user(instr[0], (u16 __user *)msk_isa16_mode(xcp->cp0_epc))) ||
2420                             (get_user(instr[1], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 2))) ||
2421                             (get_user(instr[2], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 4))) ||
2422                             (get_user(instr[3], (u16 __user *)msk_isa16_mode(xcp->cp0_epc + 6)))) {
2423                                 MIPS_FPU_EMU_INC_STATS(errors);
2424                                 return SIGBUS;
2425                         }
2426                         instr_ptr = instr;
2427
2428                         /* Get first instruction. */
2429                         if (mm_insn_16bit(*instr_ptr)) {
2430                                 /* Duplicate the half-word. */
2431                                 dec_insn.insn = (*instr_ptr << 16) |
2432                                         (*instr_ptr);
2433                                 /* 16-bit instruction. */
2434                                 dec_insn.pc_inc = 2;
2435                                 instr_ptr += 1;
2436                         } else {
2437                                 dec_insn.insn = (*instr_ptr << 16) |
2438                                         *(instr_ptr+1);
2439                                 /* 32-bit instruction. */
2440                                 dec_insn.pc_inc = 4;
2441                                 instr_ptr += 2;
2442                         }
2443                         /* Get second instruction. */
2444                         if (mm_insn_16bit(*instr_ptr)) {
2445                                 /* Duplicate the half-word. */
2446                                 dec_insn.next_insn = (*instr_ptr << 16) |
2447                                         (*instr_ptr);
2448                                 /* 16-bit instruction. */
2449                                 dec_insn.next_pc_inc = 2;
2450                         } else {
2451                                 dec_insn.next_insn = (*instr_ptr << 16) |
2452                                         *(instr_ptr+1);
2453                                 /* 32-bit instruction. */
2454                                 dec_insn.next_pc_inc = 4;
2455                         }
2456                         dec_insn.micro_mips_mode = 1;
2457                 } else {
2458                         if ((get_user(dec_insn.insn,
2459                             (mips_instruction __user *) xcp->cp0_epc)) ||
2460                             (get_user(dec_insn.next_insn,
2461                             (mips_instruction __user *)(xcp->cp0_epc+4)))) {
2462                                 MIPS_FPU_EMU_INC_STATS(errors);
2463                                 return SIGBUS;
2464                         }
2465                         dec_insn.pc_inc = 4;
2466                         dec_insn.next_pc_inc = 4;
2467                         dec_insn.micro_mips_mode = 0;
2468                 }
2469
2470                 if ((dec_insn.insn == 0) ||
2471                    ((dec_insn.pc_inc == 2) &&
2472                    ((dec_insn.insn & 0xffff) == MM_NOP16)))
2473                         xcp->cp0_epc += dec_insn.pc_inc;        /* Skip NOPs */
2474                 else {
2475                         /*
2476                          * The 'ieee754_csr' is an alias of ctx->fcr31.
2477                          * No need to copy ctx->fcr31 to ieee754_csr.
2478                          */
2479                         sig = cop1Emulate(xcp, ctx, dec_insn, fault_addr);
2480                 }
2481
2482                 if (has_fpu)
2483                         break;
2484                 if (sig)
2485                         break;
2486
2487                 cond_resched();
2488         } while (xcp->cp0_epc > prevepc);
2489
2490         /* SIGILL indicates a non-fpu instruction */
2491         if (sig == SIGILL && xcp->cp0_epc != oldepc)
2492                 /* but if EPC has advanced, then ignore it */
2493                 sig = 0;
2494
2495         return sig;
2496 }