target-cris/op_helper.c

   1 /*
   2  *  CRIS helper routines
   3  *
   4  *  Copyright (c) 2007 AXIS Communications
   5  *  Written by Edgar E. Iglesias
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Lesser General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Lesser General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Lesser General Public
  18  * License along with this library; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA  02110-1301 USA
  20  */
  21
  22 #include "exec.h"
  23 #include "mmu.h"
  24 #include "helper.h"
  25 #include "host-utils.h"
  26
  27 //#define CRIS_OP_HELPER_DEBUG
  28
  29
  30 #ifdef CRIS_OP_HELPER_DEBUG
  31 #define D(x) x
  32 #define D_LOG(...) qemu_log(__VA__ARGS__)
  33 #else
  34 #define D(x)
  35 #define D_LOG(...) do { } while (0)
  36 #endif
  37
  38 #if !defined(CONFIG_USER_ONLY)
  39
  40 #define MMUSUFFIX _mmu
  41
  42 #define SHIFT 0
  43 #include "softmmu_template.h"
  44
  45 #define SHIFT 1
  46 #include "softmmu_template.h"
  47
  48 #define SHIFT 2
  49 #include "softmmu_template.h"
  50
  51 #define SHIFT 3
  52 #include "softmmu_template.h"
  53
  54 /* Try to fill the TLB and return an exception if error. If retaddr is
  55    NULL, it means that the function was called in C code (i.e. not
  56    from generated code or from helper.c) */
  57 /* XXX: fix it to restore all registers */
  58 void tlb_fill (target_ulong addr, int is_write, int mmu_idx, void *retaddr)
  59 {
  60     TranslationBlock *tb;
  61     CPUState *saved_env;
  62     unsigned long pc;
  63     int ret;
  64
  65     /* XXX: hack to restore env in all cases, even if not called from
  66        generated code */
  67     saved_env = env;
  68     env = cpu_single_env;
  69
  70     D_LOG("%s pc=%x tpc=%x ra=%x\n", __func__,
  71              env->pc, env->debug1, retaddr);
  72     ret = cpu_cris_handle_mmu_fault(env, addr, is_write, mmu_idx, 1);
  73     if (unlikely(ret)) {
  74         if (retaddr) {
  75             /* now we have a real cpu fault */
  76             pc = (unsigned long)retaddr;
  77             tb = tb_find_pc(pc);
  78             if (tb) {
  79                 /* the PC is inside the translated code. It means that we have
  80                    a virtual CPU fault */
  81                 cpu_restore_state(tb, env, pc, NULL);
  82
  83                 /* Evaluate flags after retranslation.  */
  84                 helper_top_evaluate_flags();
  85             }
  86         }
  87         cpu_loop_exit();
  88     }
  89     env = saved_env;
  90 }
  91
  92 #endif
  93
  94 void helper_raise_exception(uint32_t index)
  95 {
  96         env->exception_index = index;
  97         cpu_loop_exit();
  98 }
  99
 100 void helper_tlb_flush_pid(uint32_t pid)
 101 {
 102 #if !defined(CONFIG_USER_ONLY)
 103         pid &= 0xff;
 104         if (pid != (env->pregs[PR_PID] & 0xff))
 105                 cris_mmu_flush_pid(env, env->pregs[PR_PID]);
 106 #endif
 107 }
 108
 109 void helper_spc_write(uint32_t new_spc)
 110 {
 111 #if !defined(CONFIG_USER_ONLY)
 112         tlb_flush_page(env, env->pregs[PR_SPC]);
 113         tlb_flush_page(env, new_spc);
 114 #endif
 115 }
 116
 117 void helper_dump(uint32_t a0, uint32_t a1, uint32_t a2)
 118 {
 119         qemu_log("%s: a0=%x a1=%x\n", __func__, a0, a1);
 120 }
 121
 122 /* Used by the tlb decoder.  */
 123 #define EXTRACT_FIELD(src, start, end) \
 124             (((src) >> start) & ((1 << (end - start + 1)) - 1))
 125
 126 void helper_movl_sreg_reg (uint32_t sreg, uint32_t reg)
 127 {
 128         uint32_t srs;
 129         srs = env->pregs[PR_SRS];
 130         srs &= 3;
 131         env->sregs[srs][sreg] = env->regs[reg];
 132
 133 #if !defined(CONFIG_USER_ONLY)
 134         if (srs == 1 || srs == 2) {
 135                 if (sreg == 6) {
 136                         /* Writes to tlb-hi write to mm_cause as a side
 137                            effect.  */
 138                         env->sregs[SFR_RW_MM_TLB_HI] = env->regs[reg];
 139                         env->sregs[SFR_R_MM_CAUSE] = env->regs[reg];
 140                 }
 141                 else if (sreg == 5) {
 142                         uint32_t set;
 143                         uint32_t idx;
 144                         uint32_t lo, hi;
 145                         uint32_t vaddr;
 146                         int tlb_v;
 147
 148                         idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
 149                         set >>= 4;
 150                         set &= 3;
 151
 152                         idx &= 15;
 153                         /* We've just made a write to tlb_lo.  */
 154                         lo = env->sregs[SFR_RW_MM_TLB_LO];
 155                         /* Writes are done via r_mm_cause.  */
 156                         hi = env->sregs[SFR_R_MM_CAUSE];
 157
 158                         vaddr = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].hi,
 159                                               13, 31);
 160                         vaddr <<= TARGET_PAGE_BITS;
 161                         tlb_v = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].lo,
 162                                             3, 3);
 163                         env->tlbsets[srs - 1][set][idx].lo = lo;
 164                         env->tlbsets[srs - 1][set][idx].hi = hi;
 165
 166                         D_LOG("tlb flush vaddr=%x v=%d pc=%x\n",
 167                                   vaddr, tlb_v, env->pc);
 168                         tlb_flush_page(env, vaddr);
 169                 }
 170         }
 171 #endif
 172 }
 173
 174 void helper_movl_reg_sreg (uint32_t reg, uint32_t sreg)
 175 {
 176         uint32_t srs;
 177         env->pregs[PR_SRS] &= 3;
 178         srs = env->pregs[PR_SRS];
 179
 180 #if !defined(CONFIG_USER_ONLY)
 181         if (srs == 1 || srs == 2)
 182         {
 183                 uint32_t set;
 184                 uint32_t idx;
 185                 uint32_t lo, hi;
 186
 187                 idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
 188                 set >>= 4;
 189                 set &= 3;
 190                 idx &= 15;
 191
 192                 /* Update the mirror regs.  */
 193                 hi = env->tlbsets[srs - 1][set][idx].hi;
 194                 lo = env->tlbsets[srs - 1][set][idx].lo;
 195                 env->sregs[SFR_RW_MM_TLB_HI] = hi;
 196                 env->sregs[SFR_RW_MM_TLB_LO] = lo;
 197         }
 198 #endif
 199         env->regs[reg] = env->sregs[srs][sreg];
 200 }
 201
 202 static void cris_ccs_rshift(CPUState *env)
 203 {
 204         uint32_t ccs;
 205
 206         /* Apply the ccs shift.  */
 207         ccs = env->pregs[PR_CCS];
 208         ccs = (ccs & 0xc0000000) | ((ccs & 0x0fffffff) >> 10);
 209         if (ccs & U_FLAG)
 210         {
 211                 /* Enter user mode.  */
 212                 env->ksp = env->regs[R_SP];
 213                 env->regs[R_SP] = env->pregs[PR_USP];
 214         }
 215
 216         env->pregs[PR_CCS] = ccs;
 217 }
 218
 219 void helper_rfe(void)
 220 {
 221         int rflag = env->pregs[PR_CCS] & R_FLAG;
 222
 223         D_LOG("rfe: erp=%x pid=%x ccs=%x btarget=%x\n",
 224                  env->pregs[PR_ERP], env->pregs[PR_PID],
 225                  env->pregs[PR_CCS],
 226                  env->btarget);
 227
 228         cris_ccs_rshift(env);
 229
 230         /* RFE sets the P_FLAG only if the R_FLAG is not set.  */
 231         if (!rflag)
 232                 env->pregs[PR_CCS] |= P_FLAG;
 233 }
 234
 235 void helper_rfn(void)
 236 {
 237         int rflag = env->pregs[PR_CCS] & R_FLAG;
 238
 239         D_LOG("rfn: erp=%x pid=%x ccs=%x btarget=%x\n",
 240                  env->pregs[PR_ERP], env->pregs[PR_PID],
 241                  env->pregs[PR_CCS],
 242                  env->btarget);
 243
 244         cris_ccs_rshift(env);
 245
 246         /* Set the P_FLAG only if the R_FLAG is not set.  */
 247         if (!rflag)
 248                 env->pregs[PR_CCS] |= P_FLAG;
 249
 250     /* Always set the M flag.  */
 251     env->pregs[PR_CCS] |= M_FLAG;
 252 }
 253
 254 uint32_t helper_lz(uint32_t t0)
 255 {
 256         return clz32(t0);
 257 }
 258
 259 uint32_t helper_btst(uint32_t t0, uint32_t t1, uint32_t ccs)
 260 {
 261         /* FIXME: clean this up.  */
 262
 263         /* des ref:
 264            The N flag is set according to the selected bit in the dest reg.
 265            The Z flag is set if the selected bit and all bits to the right are
 266            zero.
 267            The X flag is cleared.
 268            Other flags are left untouched.
 269            The destination reg is not affected.*/
 270         unsigned int fz, sbit, bset, mask, masked_t0;
 271
 272         sbit = t1 & 31;
 273         bset = !!(t0 & (1 << sbit));
 274         mask = sbit == 31 ? -1 : (1 << (sbit + 1)) - 1;
 275         masked_t0 = t0 & mask;
 276         fz = !(masked_t0 | bset);
 277
 278         /* Clear the X, N and Z flags.  */
 279         ccs = ccs & ~(X_FLAG | N_FLAG | Z_FLAG);
 280         /* Set the N and Z flags accordingly.  */
 281         ccs |= (bset << 3) | (fz << 2);
 282         return ccs;
 283 }
 284
 285 static inline uint32_t evaluate_flags_writeback(uint32_t flags, uint32_t ccs)
 286 {
 287         unsigned int x, z, mask;
 288
 289         /* Extended arithmetics, leave the z flag alone.  */
 290         x = env->cc_x;
 291         mask = env->cc_mask | X_FLAG;
 292         if (x) {
 293                 z = flags & Z_FLAG;
 294                 mask = mask & ~z;
 295         }
 296         flags &= mask;
 297
 298         /* all insn clear the x-flag except setf or clrf.  */
 299         ccs &= ~mask;
 300         ccs |= flags;
 301         return ccs;
 302 }
 303
 304 uint32_t helper_evaluate_flags_muls(uint32_t ccs, uint32_t res, uint32_t mof)
 305 {
 306         uint32_t flags = 0;
 307         int64_t tmp;
 308         int dneg;
 309
 310         dneg = ((int32_t)res) < 0;
 311
 312         tmp = mof;
 313         tmp <<= 32;
 314         tmp |= res;
 315         if (tmp == 0)
 316                 flags |= Z_FLAG;
 317         else if (tmp < 0)
 318                 flags |= N_FLAG;
 319         if ((dneg && mof != -1)
 320             || (!dneg && mof != 0))
 321                 flags |= V_FLAG;
 322         return evaluate_flags_writeback(flags, ccs);
 323 }
 324
 325 uint32_t helper_evaluate_flags_mulu(uint32_t ccs, uint32_t res, uint32_t mof)
 326 {
 327         uint32_t flags = 0;
 328         uint64_t tmp;
 329
 330         tmp = mof;
 331         tmp <<= 32;
 332         tmp |= res;
 333         if (tmp == 0)
 334                 flags |= Z_FLAG;
 335         else if (tmp >> 63)
 336                 flags |= N_FLAG;
 337         if (mof)
 338                 flags |= V_FLAG;
 339
 340         return evaluate_flags_writeback(flags, ccs);
 341 }
 342
 343 uint32_t helper_evaluate_flags_mcp(uint32_t ccs,
 344                                    uint32_t src, uint32_t dst, uint32_t res)
 345 {
 346         uint32_t flags = 0;
 347
 348         src = src & 0x80000000;
 349         dst = dst & 0x80000000;
 350
 351         if ((res & 0x80000000L) != 0L)
 352         {
 353                 flags |= N_FLAG;
 354                 if (!src && !dst)
 355                         flags |= V_FLAG;
 356                 else if (src & dst)
 357                         flags |= R_FLAG;
 358         }
 359         else
 360         {
 361                 if (res == 0L)
 362                         flags |= Z_FLAG;
 363                 if (src & dst)
 364                         flags |= V_FLAG;
 365                 if (dst | src)
 366                         flags |= R_FLAG;
 367         }
 368
 369         return evaluate_flags_writeback(flags, ccs);
 370 }
 371
 372 uint32_t helper_evaluate_flags_alu_4(uint32_t ccs,
 373                                      uint32_t src, uint32_t dst, uint32_t res)
 374 {
 375         uint32_t flags = 0;
 376
 377         src = src & 0x80000000;
 378         dst = dst & 0x80000000;
 379
 380         if ((res & 0x80000000L) != 0L)
 381         {
 382                 flags |= N_FLAG;
 383                 if (!src && !dst)
 384                         flags |= V_FLAG;
 385                 else if (src & dst)
 386                         flags |= C_FLAG;
 387         }
 388         else
 389         {
 390                 if (res == 0L)
 391                         flags |= Z_FLAG;
 392                 if (src & dst)
 393                         flags |= V_FLAG;
 394                 if (dst | src)
 395                         flags |= C_FLAG;
 396         }
 397
 398         return evaluate_flags_writeback(flags, ccs);
 399 }
 400
 401 uint32_t helper_evaluate_flags_sub_4(uint32_t ccs,
 402                                      uint32_t src, uint32_t dst, uint32_t res)
 403 {
 404         uint32_t flags = 0;
 405
 406         src = (~src) & 0x80000000;
 407         dst = dst & 0x80000000;
 408
 409         if ((res & 0x80000000L) != 0L)
 410         {
 411                 flags |= N_FLAG;
 412                 if (!src && !dst)
 413                         flags |= V_FLAG;
 414                 else if (src & dst)
 415                         flags |= C_FLAG;
 416         }
 417         else
 418         {
 419                 if (res == 0L)
 420                         flags |= Z_FLAG;
 421                 if (src & dst)
 422                         flags |= V_FLAG;
 423                 if (dst | src)
 424                         flags |= C_FLAG;
 425         }
 426
 427         flags ^= C_FLAG;
 428         return evaluate_flags_writeback(flags, ccs);
 429 }
 430
 431 uint32_t helper_evaluate_flags_move_4(uint32_t ccs, uint32_t res)
 432 {
 433         uint32_t flags = 0;
 434
 435         if ((int32_t)res < 0)
 436                 flags |= N_FLAG;
 437         else if (res == 0L)
 438                 flags |= Z_FLAG;
 439
 440         return evaluate_flags_writeback(flags, ccs);
 441 }
 442 uint32_t helper_evaluate_flags_move_2(uint32_t ccs, uint32_t res)
 443 {
 444         uint32_t flags = 0;
 445
 446         if ((int16_t)res < 0L)
 447                 flags |= N_FLAG;
 448         else if (res == 0)
 449                 flags |= Z_FLAG;
 450
 451         return evaluate_flags_writeback(flags, ccs);
 452 }
 453
 454 /* TODO: This is expensive. We could split things up and only evaluate part of
 455    CCR on a need to know basis. For now, we simply re-evaluate everything.  */
 456 void  helper_evaluate_flags(void)
 457 {
 458         uint32_t src, dst, res;
 459         uint32_t flags = 0;
 460
 461         src = env->cc_src;
 462         dst = env->cc_dest;
 463         res = env->cc_result;
 464
 465         if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 466                 src = ~src;
 467
 468         /* Now, evaluate the flags. This stuff is based on
 469            Per Zander's CRISv10 simulator.  */
 470         switch (env->cc_size)
 471         {
 472                 case 1:
 473                         if ((res & 0x80L) != 0L)
 474                         {
 475                                 flags |= N_FLAG;
 476                                 if (((src & 0x80L) == 0L)
 477                                     && ((dst & 0x80L) == 0L))
 478                                 {
 479                                         flags |= V_FLAG;
 480                                 }
 481                                 else if (((src & 0x80L) != 0L)
 482                                          && ((dst & 0x80L) != 0L))
 483                                 {
 484                                         flags |= C_FLAG;
 485                                 }
 486                         }
 487                         else
 488                         {
 489                                 if ((res & 0xFFL) == 0L)
 490                                 {
 491                                         flags |= Z_FLAG;
 492                                 }
 493                                 if (((src & 0x80L) != 0L)
 494                                     && ((dst & 0x80L) != 0L))
 495                                 {
 496                                         flags |= V_FLAG;
 497                                 }
 498                                 if ((dst & 0x80L) != 0L
 499                                     || (src & 0x80L) != 0L)
 500                                 {
 501                                         flags |= C_FLAG;
 502                                 }
 503                         }
 504                         break;
 505                 case 2:
 506                         if ((res & 0x8000L) != 0L)
 507                         {
 508                                 flags |= N_FLAG;
 509                                 if (((src & 0x8000L) == 0L)
 510                                     && ((dst & 0x8000L) == 0L))
 511                                 {
 512                                         flags |= V_FLAG;
 513                                 }
 514                                 else if (((src & 0x8000L) != 0L)
 515                                          && ((dst & 0x8000L) != 0L))
 516                                 {
 517                                         flags |= C_FLAG;
 518                                 }
 519                         }
 520                         else
 521                         {
 522                                 if ((res & 0xFFFFL) == 0L)
 523                                 {
 524                                         flags |= Z_FLAG;
 525                                 }
 526                                 if (((src & 0x8000L) != 0L)
 527                                     && ((dst & 0x8000L) != 0L))
 528                                 {
 529                                         flags |= V_FLAG;
 530                                 }
 531                                 if ((dst & 0x8000L) != 0L
 532                                     || (src & 0x8000L) != 0L)
 533                                 {
 534                                         flags |= C_FLAG;
 535                                 }
 536                         }
 537                         break;
 538                 case 4:
 539                         if ((res & 0x80000000L) != 0L)
 540                         {
 541                                 flags |= N_FLAG;
 542                                 if (((src & 0x80000000L) == 0L)
 543                                     && ((dst & 0x80000000L) == 0L))
 544                                 {
 545                                         flags |= V_FLAG;
 546                                 }
 547                                 else if (((src & 0x80000000L) != 0L) &&
 548                                          ((dst & 0x80000000L) != 0L))
 549                                 {
 550                                         flags |= C_FLAG;
 551                                 }
 552                         }
 553                         else
 554                         {
 555                                 if (res == 0L)
 556                                         flags |= Z_FLAG;
 557                                 if (((src & 0x80000000L) != 0L)
 558                                     && ((dst & 0x80000000L) != 0L))
 559                                         flags |= V_FLAG;
 560                                 if ((dst & 0x80000000L) != 0L
 561                                     || (src & 0x80000000L) != 0L)
 562                                         flags |= C_FLAG;
 563                         }
 564                         break;
 565                 default:
 566                         break;
 567         }
 568
 569         if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 570                 flags ^= C_FLAG;
 571
 572         env->pregs[PR_CCS] = evaluate_flags_writeback(flags, env->pregs[PR_CCS]);
 573 }
 574
 575 void helper_top_evaluate_flags(void)
 576 {
 577         switch (env->cc_op)
 578         {
 579                 case CC_OP_MCP:
 580                         env->pregs[PR_CCS] = helper_evaluate_flags_mcp(
 581                                         env->pregs[PR_CCS], env->cc_src,
 582                                         env->cc_dest, env->cc_result);
 583                         break;
 584                 case CC_OP_MULS:
 585                         env->pregs[PR_CCS] = helper_evaluate_flags_muls(
 586                                         env->pregs[PR_CCS], env->cc_result,
 587                                         env->pregs[PR_MOF]);
 588                         break;
 589                 case CC_OP_MULU:
 590                         env->pregs[PR_CCS] = helper_evaluate_flags_mulu(
 591                                         env->pregs[PR_CCS], env->cc_result,
 592                                         env->pregs[PR_MOF]);
 593                         break;
 594                 case CC_OP_MOVE:
 595                 case CC_OP_AND:
 596                 case CC_OP_OR:
 597                 case CC_OP_XOR:
 598                 case CC_OP_ASR:
 599                 case CC_OP_LSR:
 600                 case CC_OP_LSL:
 601                 switch (env->cc_size)
 602                 {
 603                         case 4:
 604                                 env->pregs[PR_CCS] =
 605                                         helper_evaluate_flags_move_4(
 606                                                         env->pregs[PR_CCS],
 607                                                         env->cc_result);
 608                                 break;
 609                         case 2:
 610                                 env->pregs[PR_CCS] =
 611                                         helper_evaluate_flags_move_2(
 612                                                         env->pregs[PR_CCS],
 613                                                         env->cc_result);
 614                                 break;
 615                         default:
 616                                 helper_evaluate_flags();
 617                                 break;
 618                 }
 619                 break;
 620                 case CC_OP_FLAGS:
 621                         /* live.  */
 622                         break;
 623                 case CC_OP_SUB:
 624                 case CC_OP_CMP:
 625                         if (env->cc_size == 4)
 626                                 env->pregs[PR_CCS] =
 627                                         helper_evaluate_flags_sub_4(
 628                                                 env->pregs[PR_CCS],
 629                                                 env->cc_src, env->cc_dest,
 630                                                 env->cc_result);
 631                         else
 632                                 helper_evaluate_flags();
 633                         break;
 634                 default:
 635                 {
 636                         switch (env->cc_size)
 637                         {
 638                         case 4:
 639                                 env->pregs[PR_CCS] =
 640                                         helper_evaluate_flags_alu_4(
 641                                                 env->pregs[PR_CCS],
 642                                                 env->cc_src, env->cc_dest,
 643                                                 env->cc_result);
 644                                 break;
 645                         default:
 646                                 helper_evaluate_flags();
 647                                 break;
 648                         }
 649                 }
 650                 break;
 651         }
 652 }