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, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include "exec.h"
  22 #include "mmu.h"
  23 #include "helper.h"
  24 #include "host-utils.h"
  25
  26 //#define CRIS_OP_HELPER_DEBUG
  27
  28
  29 #ifdef CRIS_OP_HELPER_DEBUG
  30 #define D(x) x
  31 #define D_LOG(...) qemu_log(__VA__ARGS__)
  32 #else
  33 #define D(x)
  34 #define D_LOG(...) do { } while (0)
  35 #endif
  36
  37 #if !defined(CONFIG_USER_ONLY)
  38
  39 #define MMUSUFFIX _mmu
  40
  41 #define SHIFT 0
  42 #include "softmmu_template.h"
  43
  44 #define SHIFT 1
  45 #include "softmmu_template.h"
  46
  47 #define SHIFT 2
  48 #include "softmmu_template.h"
  49
  50 #define SHIFT 3
  51 #include "softmmu_template.h"
  52
  53 /* Try to fill the TLB and return an exception if error. If retaddr is
  54    NULL, it means that the function was called in C code (i.e. not
  55    from generated code or from helper.c) */
  56 /* XXX: fix it to restore all registers */
  57 void tlb_fill (target_ulong addr, int is_write, int mmu_idx, void *retaddr)
  58 {
  59     TranslationBlock *tb;
  60     CPUState *saved_env;
  61     unsigned long pc;
  62     int ret;
  63
  64     /* XXX: hack to restore env in all cases, even if not called from
  65        generated code */
  66     saved_env = env;
  67     env = cpu_single_env;
  68
  69     D_LOG("%s pc=%x tpc=%x ra=%x\n", __func__,
  70              env->pc, env->debug1, retaddr);
  71     ret = cpu_cris_handle_mmu_fault(env, addr, is_write, mmu_idx, 1);
  72     if (unlikely(ret)) {
  73         if (retaddr) {
  74             /* now we have a real cpu fault */
  75             pc = (unsigned long)retaddr;
  76             tb = tb_find_pc(pc);
  77             if (tb) {
  78                 /* the PC is inside the translated code. It means that we have
  79                    a virtual CPU fault */
  80                 cpu_restore_state(tb, env, pc);
  81
  82                 /* Evaluate flags after retranslation.  */
  83                 helper_top_evaluate_flags();
  84             }
  85         }
  86         cpu_loop_exit();
  87     }
  88     env = saved_env;
  89 }
  90
  91 #endif
  92
  93 void helper_raise_exception(uint32_t index)
  94 {
  95         env->exception_index = index;
  96         cpu_loop_exit();
  97 }
  98
  99 void helper_tlb_flush_pid(uint32_t pid)
 100 {
 101 #if !defined(CONFIG_USER_ONLY)
 102         pid &= 0xff;
 103         if (pid != (env->pregs[PR_PID] & 0xff))
 104                 cris_mmu_flush_pid(env, env->pregs[PR_PID]);
 105 #endif
 106 }
 107
 108 void helper_spc_write(uint32_t new_spc)
 109 {
 110 #if !defined(CONFIG_USER_ONLY)
 111         tlb_flush_page(env, env->pregs[PR_SPC]);
 112         tlb_flush_page(env, new_spc);
 113 #endif
 114 }
 115
 116 void helper_dump(uint32_t a0, uint32_t a1, uint32_t a2)
 117 {
 118         qemu_log("%s: a0=%x a1=%x\n", __func__, a0, a1);
 119 }
 120
 121 /* Used by the tlb decoder.  */
 122 #define EXTRACT_FIELD(src, start, end) \
 123             (((src) >> start) & ((1 << (end - start + 1)) - 1))
 124
 125 void helper_movl_sreg_reg (uint32_t sreg, uint32_t reg)
 126 {
 127         uint32_t srs;
 128         srs = env->pregs[PR_SRS];
 129         srs &= 3;
 130         env->sregs[srs][sreg] = env->regs[reg];
 131
 132 #if !defined(CONFIG_USER_ONLY)
 133         if (srs == 1 || srs == 2) {
 134                 if (sreg == 6) {
 135                         /* Writes to tlb-hi write to mm_cause as a side
 136                            effect.  */
 137                         env->sregs[SFR_RW_MM_TLB_HI] = env->regs[reg];
 138                         env->sregs[SFR_R_MM_CAUSE] = env->regs[reg];
 139                 }
 140                 else if (sreg == 5) {
 141                         uint32_t set;
 142                         uint32_t idx;
 143                         uint32_t lo, hi;
 144                         uint32_t vaddr;
 145                         int tlb_v;
 146
 147                         idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
 148                         set >>= 4;
 149                         set &= 3;
 150
 151                         idx &= 15;
 152                         /* We've just made a write to tlb_lo.  */
 153                         lo = env->sregs[SFR_RW_MM_TLB_LO];
 154                         /* Writes are done via r_mm_cause.  */
 155                         hi = env->sregs[SFR_R_MM_CAUSE];
 156
 157                         vaddr = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].hi,
 158                                               13, 31);
 159                         vaddr <<= TARGET_PAGE_BITS;
 160                         tlb_v = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].lo,
 161                                             3, 3);
 162                         env->tlbsets[srs - 1][set][idx].lo = lo;
 163                         env->tlbsets[srs - 1][set][idx].hi = hi;
 164
 165                         D_LOG("tlb flush vaddr=%x v=%d pc=%x\n",
 166                                   vaddr, tlb_v, env->pc);
 167                         if (tlb_v) {
 168                                 tlb_flush_page(env, vaddr);
 169                         }
 170                 }
 171         }
 172 #endif
 173 }
 174
 175 void helper_movl_reg_sreg (uint32_t reg, uint32_t sreg)
 176 {
 177         uint32_t srs;
 178         env->pregs[PR_SRS] &= 3;
 179         srs = env->pregs[PR_SRS];
 180
 181 #if !defined(CONFIG_USER_ONLY)
 182         if (srs == 1 || srs == 2)
 183         {
 184                 uint32_t set;
 185                 uint32_t idx;
 186                 uint32_t lo, hi;
 187
 188                 idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
 189                 set >>= 4;
 190                 set &= 3;
 191                 idx &= 15;
 192
 193                 /* Update the mirror regs.  */
 194                 hi = env->tlbsets[srs - 1][set][idx].hi;
 195                 lo = env->tlbsets[srs - 1][set][idx].lo;
 196                 env->sregs[SFR_RW_MM_TLB_HI] = hi;
 197                 env->sregs[SFR_RW_MM_TLB_LO] = lo;
 198         }
 199 #endif
 200         env->regs[reg] = env->sregs[srs][sreg];
 201 }
 202
 203 static void cris_ccs_rshift(CPUState *env)
 204 {
 205         uint32_t ccs;
 206
 207         /* Apply the ccs shift.  */
 208         ccs = env->pregs[PR_CCS];
 209         ccs = (ccs & 0xc0000000) | ((ccs & 0x0fffffff) >> 10);
 210         if (ccs & U_FLAG)
 211         {
 212                 /* Enter user mode.  */
 213                 env->ksp = env->regs[R_SP];
 214                 env->regs[R_SP] = env->pregs[PR_USP];
 215         }
 216
 217         env->pregs[PR_CCS] = ccs;
 218 }
 219
 220 void helper_rfe(void)
 221 {
 222         int rflag = env->pregs[PR_CCS] & R_FLAG;
 223
 224         D_LOG("rfe: erp=%x pid=%x ccs=%x btarget=%x\n",
 225                  env->pregs[PR_ERP], env->pregs[PR_PID],
 226                  env->pregs[PR_CCS],
 227                  env->btarget);
 228
 229         cris_ccs_rshift(env);
 230
 231         /* RFE sets the P_FLAG only if the R_FLAG is not set.  */
 232         if (!rflag)
 233                 env->pregs[PR_CCS] |= P_FLAG;
 234 }
 235
 236 void helper_rfn(void)
 237 {
 238         int rflag = env->pregs[PR_CCS] & R_FLAG;
 239
 240         D_LOG("rfn: erp=%x pid=%x ccs=%x btarget=%x\n",
 241                  env->pregs[PR_ERP], env->pregs[PR_PID],
 242                  env->pregs[PR_CCS],
 243                  env->btarget);
 244
 245         cris_ccs_rshift(env);
 246
 247         /* Set the P_FLAG only if the R_FLAG is not set.  */
 248         if (!rflag)
 249                 env->pregs[PR_CCS] |= P_FLAG;
 250
 251     /* Always set the M flag.  */
 252     env->pregs[PR_CCS] |= M_FLAG;
 253 }
 254
 255 uint32_t helper_lz(uint32_t t0)
 256 {
 257         return clz32(t0);
 258 }
 259
 260 uint32_t helper_btst(uint32_t t0, uint32_t t1, uint32_t ccs)
 261 {
 262         /* FIXME: clean this up.  */
 263
 264         /* des ref:
 265            The N flag is set according to the selected bit in the dest reg.
 266            The Z flag is set if the selected bit and all bits to the right are
 267            zero.
 268            The X flag is cleared.
 269            Other flags are left untouched.
 270            The destination reg is not affected.*/
 271         unsigned int fz, sbit, bset, mask, masked_t0;
 272
 273         sbit = t1 & 31;
 274         bset = !!(t0 & (1 << sbit));
 275         mask = sbit == 31 ? -1 : (1 << (sbit + 1)) - 1;
 276         masked_t0 = t0 & mask;
 277         fz = !(masked_t0 | bset);
 278
 279         /* Clear the X, N and Z flags.  */
 280         ccs = ccs & ~(X_FLAG | N_FLAG | Z_FLAG);
 281         if (env->pregs[PR_VR] < 32)
 282                 ccs &= ~(V_FLAG | C_FLAG);
 283         /* Set the N and Z flags accordingly.  */
 284         ccs |= (bset << 3) | (fz << 2);
 285         return ccs;
 286 }
 287
 288 static inline uint32_t evaluate_flags_writeback(uint32_t flags, uint32_t ccs)
 289 {
 290         unsigned int x, z, mask;
 291
 292         /* Extended arithmetics, leave the z flag alone.  */
 293         x = env->cc_x;
 294         mask = env->cc_mask | X_FLAG;
 295         if (x) {
 296                 z = flags & Z_FLAG;
 297                 mask = mask & ~z;
 298         }
 299         flags &= mask;
 300
 301         /* all insn clear the x-flag except setf or clrf.  */
 302         ccs &= ~mask;
 303         ccs |= flags;
 304         return ccs;
 305 }
 306
 307 uint32_t helper_evaluate_flags_muls(uint32_t ccs, uint32_t res, uint32_t mof)
 308 {
 309         uint32_t flags = 0;
 310         int64_t tmp;
 311         int dneg;
 312
 313         dneg = ((int32_t)res) < 0;
 314
 315         tmp = mof;
 316         tmp <<= 32;
 317         tmp |= res;
 318         if (tmp == 0)
 319                 flags |= Z_FLAG;
 320         else if (tmp < 0)
 321                 flags |= N_FLAG;
 322         if ((dneg && mof != -1)
 323             || (!dneg && mof != 0))
 324                 flags |= V_FLAG;
 325         return evaluate_flags_writeback(flags, ccs);
 326 }
 327
 328 uint32_t helper_evaluate_flags_mulu(uint32_t ccs, uint32_t res, uint32_t mof)
 329 {
 330         uint32_t flags = 0;
 331         uint64_t tmp;
 332
 333         tmp = mof;
 334         tmp <<= 32;
 335         tmp |= res;
 336         if (tmp == 0)
 337                 flags |= Z_FLAG;
 338         else if (tmp >> 63)
 339                 flags |= N_FLAG;
 340         if (mof)
 341                 flags |= V_FLAG;
 342
 343         return evaluate_flags_writeback(flags, ccs);
 344 }
 345
 346 uint32_t helper_evaluate_flags_mcp(uint32_t ccs,
 347                                    uint32_t src, uint32_t dst, uint32_t res)
 348 {
 349         uint32_t flags = 0;
 350
 351         src = src & 0x80000000;
 352         dst = dst & 0x80000000;
 353
 354         if ((res & 0x80000000L) != 0L)
 355         {
 356                 flags |= N_FLAG;
 357                 if (!src && !dst)
 358                         flags |= V_FLAG;
 359                 else if (src & dst)
 360                         flags |= R_FLAG;
 361         }
 362         else
 363         {
 364                 if (res == 0L)
 365                         flags |= Z_FLAG;
 366                 if (src & dst)
 367                         flags |= V_FLAG;
 368                 if (dst | src)
 369                         flags |= R_FLAG;
 370         }
 371
 372         return evaluate_flags_writeback(flags, ccs);
 373 }
 374
 375 uint32_t helper_evaluate_flags_alu_4(uint32_t ccs,
 376                                      uint32_t src, uint32_t dst, uint32_t res)
 377 {
 378         uint32_t flags = 0;
 379
 380         src = src & 0x80000000;
 381         dst = dst & 0x80000000;
 382
 383         if ((res & 0x80000000L) != 0L)
 384         {
 385                 flags |= N_FLAG;
 386                 if (!src && !dst)
 387                         flags |= V_FLAG;
 388                 else if (src & dst)
 389                         flags |= C_FLAG;
 390         }
 391         else
 392         {
 393                 if (res == 0L)
 394                         flags |= Z_FLAG;
 395                 if (src & dst)
 396                         flags |= V_FLAG;
 397                 if (dst | src)
 398                         flags |= C_FLAG;
 399         }
 400
 401         return evaluate_flags_writeback(flags, ccs);
 402 }
 403
 404 uint32_t helper_evaluate_flags_sub_4(uint32_t ccs,
 405                                      uint32_t src, uint32_t dst, uint32_t res)
 406 {
 407         uint32_t flags = 0;
 408
 409         src = (~src) & 0x80000000;
 410         dst = dst & 0x80000000;
 411
 412         if ((res & 0x80000000L) != 0L)
 413         {
 414                 flags |= N_FLAG;
 415                 if (!src && !dst)
 416                         flags |= V_FLAG;
 417                 else if (src & dst)
 418                         flags |= C_FLAG;
 419         }
 420         else
 421         {
 422                 if (res == 0L)
 423                         flags |= Z_FLAG;
 424                 if (src & dst)
 425                         flags |= V_FLAG;
 426                 if (dst | src)
 427                         flags |= C_FLAG;
 428         }
 429
 430         flags ^= C_FLAG;
 431         return evaluate_flags_writeback(flags, ccs);
 432 }
 433
 434 uint32_t helper_evaluate_flags_move_4(uint32_t ccs, uint32_t res)
 435 {
 436         uint32_t flags = 0;
 437
 438         if ((int32_t)res < 0)
 439                 flags |= N_FLAG;
 440         else if (res == 0L)
 441                 flags |= Z_FLAG;
 442
 443         return evaluate_flags_writeback(flags, ccs);
 444 }
 445 uint32_t helper_evaluate_flags_move_2(uint32_t ccs, uint32_t res)
 446 {
 447         uint32_t flags = 0;
 448
 449         if ((int16_t)res < 0L)
 450                 flags |= N_FLAG;
 451         else if (res == 0)
 452                 flags |= Z_FLAG;
 453
 454         return evaluate_flags_writeback(flags, ccs);
 455 }
 456
 457 /* TODO: This is expensive. We could split things up and only evaluate part of
 458    CCR on a need to know basis. For now, we simply re-evaluate everything.  */
 459 void  helper_evaluate_flags(void)
 460 {
 461         uint32_t src, dst, res;
 462         uint32_t flags = 0;
 463
 464         src = env->cc_src;
 465         dst = env->cc_dest;
 466         res = env->cc_result;
 467
 468         if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 469                 src = ~src;
 470
 471         /* Now, evaluate the flags. This stuff is based on
 472            Per Zander's CRISv10 simulator.  */
 473         switch (env->cc_size)
 474         {
 475                 case 1:
 476                         if ((res & 0x80L) != 0L)
 477                         {
 478                                 flags |= N_FLAG;
 479                                 if (((src & 0x80L) == 0L)
 480                                     && ((dst & 0x80L) == 0L))
 481                                 {
 482                                         flags |= V_FLAG;
 483                                 }
 484                                 else if (((src & 0x80L) != 0L)
 485                                          && ((dst & 0x80L) != 0L))
 486                                 {
 487                                         flags |= C_FLAG;
 488                                 }
 489                         }
 490                         else
 491                         {
 492                                 if ((res & 0xFFL) == 0L)
 493                                 {
 494                                         flags |= Z_FLAG;
 495                                 }
 496                                 if (((src & 0x80L) != 0L)
 497                                     && ((dst & 0x80L) != 0L))
 498                                 {
 499                                         flags |= V_FLAG;
 500                                 }
 501                                 if ((dst & 0x80L) != 0L
 502                                     || (src & 0x80L) != 0L)
 503                                 {
 504                                         flags |= C_FLAG;
 505                                 }
 506                         }
 507                         break;
 508                 case 2:
 509                         if ((res & 0x8000L) != 0L)
 510                         {
 511                                 flags |= N_FLAG;
 512                                 if (((src & 0x8000L) == 0L)
 513                                     && ((dst & 0x8000L) == 0L))
 514                                 {
 515                                         flags |= V_FLAG;
 516                                 }
 517                                 else if (((src & 0x8000L) != 0L)
 518                                          && ((dst & 0x8000L) != 0L))
 519                                 {
 520                                         flags |= C_FLAG;
 521                                 }
 522                         }
 523                         else
 524                         {
 525                                 if ((res & 0xFFFFL) == 0L)
 526                                 {
 527                                         flags |= Z_FLAG;
 528                                 }
 529                                 if (((src & 0x8000L) != 0L)
 530                                     && ((dst & 0x8000L) != 0L))
 531                                 {
 532                                         flags |= V_FLAG;
 533                                 }
 534                                 if ((dst & 0x8000L) != 0L
 535                                     || (src & 0x8000L) != 0L)
 536                                 {
 537                                         flags |= C_FLAG;
 538                                 }
 539                         }
 540                         break;
 541                 case 4:
 542                         if ((res & 0x80000000L) != 0L)
 543                         {
 544                                 flags |= N_FLAG;
 545                                 if (((src & 0x80000000L) == 0L)
 546                                     && ((dst & 0x80000000L) == 0L))
 547                                 {
 548                                         flags |= V_FLAG;
 549                                 }
 550                                 else if (((src & 0x80000000L) != 0L) &&
 551                                          ((dst & 0x80000000L) != 0L))
 552                                 {
 553                                         flags |= C_FLAG;
 554                                 }
 555                         }
 556                         else
 557                         {
 558                                 if (res == 0L)
 559                                         flags |= Z_FLAG;
 560                                 if (((src & 0x80000000L) != 0L)
 561                                     && ((dst & 0x80000000L) != 0L))
 562                                         flags |= V_FLAG;
 563                                 if ((dst & 0x80000000L) != 0L
 564                                     || (src & 0x80000000L) != 0L)
 565                                         flags |= C_FLAG;
 566                         }
 567                         break;
 568                 default:
 569                         break;
 570         }
 571
 572         if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 573                 flags ^= C_FLAG;
 574
 575         env->pregs[PR_CCS] = evaluate_flags_writeback(flags, env->pregs[PR_CCS]);
 576 }
 577
 578 void helper_top_evaluate_flags(void)
 579 {
 580         switch (env->cc_op)
 581         {
 582                 case CC_OP_MCP:
 583                         env->pregs[PR_CCS] = helper_evaluate_flags_mcp(
 584                                         env->pregs[PR_CCS], env->cc_src,
 585                                         env->cc_dest, env->cc_result);
 586                         break;
 587                 case CC_OP_MULS:
 588                         env->pregs[PR_CCS] = helper_evaluate_flags_muls(
 589                                         env->pregs[PR_CCS], env->cc_result,
 590                                         env->pregs[PR_MOF]);
 591                         break;
 592                 case CC_OP_MULU:
 593                         env->pregs[PR_CCS] = helper_evaluate_flags_mulu(
 594                                         env->pregs[PR_CCS], env->cc_result,
 595                                         env->pregs[PR_MOF]);
 596                         break;
 597                 case CC_OP_MOVE:
 598                 case CC_OP_AND:
 599                 case CC_OP_OR:
 600                 case CC_OP_XOR:
 601                 case CC_OP_ASR:
 602                 case CC_OP_LSR:
 603                 case CC_OP_LSL:
 604                 switch (env->cc_size)
 605                 {
 606                         case 4:
 607                                 env->pregs[PR_CCS] =
 608                                         helper_evaluate_flags_move_4(
 609                                                         env->pregs[PR_CCS],
 610                                                         env->cc_result);
 611                                 break;
 612                         case 2:
 613                                 env->pregs[PR_CCS] =
 614                                         helper_evaluate_flags_move_2(
 615                                                         env->pregs[PR_CCS],
 616                                                         env->cc_result);
 617                                 break;
 618                         default:
 619                                 helper_evaluate_flags();
 620                                 break;
 621                 }
 622                 break;
 623                 case CC_OP_FLAGS:
 624                         /* live.  */
 625                         break;
 626                 case CC_OP_SUB:
 627                 case CC_OP_CMP:
 628                         if (env->cc_size == 4)
 629                                 env->pregs[PR_CCS] =
 630                                         helper_evaluate_flags_sub_4(
 631                                                 env->pregs[PR_CCS],
 632                                                 env->cc_src, env->cc_dest,
 633                                                 env->cc_result);
 634                         else
 635                                 helper_evaluate_flags();
 636                         break;
 637                 default:
 638                 {
 639                         switch (env->cc_size)
 640                         {
 641                         case 4:
 642                                 env->pregs[PR_CCS] =
 643                                         helper_evaluate_flags_alu_4(
 644                                                 env->pregs[PR_CCS],
 645                                                 env->cc_src, env->cc_dest,
 646                                                 env->cc_result);
 647                                 break;
 648                         default:
 649                                 helper_evaluate_flags();
 650                                 break;
 651                         }
 652                 }
 653                 break;
 654         }
 655 }