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 <assert.h>
  23 #include "exec.h"
  24 #include "mmu.h"
  25 #include "helper.h"
  26
  27 #define D(x)
  28
  29 #if !defined(CONFIG_USER_ONLY)
  30
  31 #define MMUSUFFIX _mmu
  32
  33 #define SHIFT 0
  34 #include "softmmu_template.h"
  35
  36 #define SHIFT 1
  37 #include "softmmu_template.h"
  38
  39 #define SHIFT 2
  40 #include "softmmu_template.h"
  41
  42 #define SHIFT 3
  43 #include "softmmu_template.h"
  44
  45 /* Try to fill the TLB and return an exception if error. If retaddr is
  46    NULL, it means that the function was called in C code (i.e. not
  47    from generated code or from helper.c) */
  48 /* XXX: fix it to restore all registers */
  49 void tlb_fill (target_ulong addr, int is_write, int mmu_idx, void *retaddr)
  50 {
  51     TranslationBlock *tb;
  52     CPUState *saved_env;
  53     unsigned long pc;
  54     int ret;
  55
  56     /* XXX: hack to restore env in all cases, even if not called from
  57        generated code */
  58     saved_env = env;
  59     env = cpu_single_env;
  60
  61     D(fprintf(logfile, "%s pc=%x tpc=%x ra=%x\n", __func__,
  62              env->pc, env->debug1, retaddr));
  63     ret = cpu_cris_handle_mmu_fault(env, addr, is_write, mmu_idx, 1);
  64     if (unlikely(ret)) {
  65         if (retaddr) {
  66             /* now we have a real cpu fault */
  67             pc = (unsigned long)retaddr;
  68             tb = tb_find_pc(pc);
  69             if (tb) {
  70                 /* the PC is inside the translated code. It means that we have
  71                    a virtual CPU fault */
  72                 cpu_restore_state(tb, env, pc, NULL);
  73
  74                 /* Evaluate flags after retranslation.  */
  75                 helper_top_evaluate_flags();
  76             }
  77         }
  78         cpu_loop_exit();
  79     }
  80     env = saved_env;
  81 }
  82
  83 #endif
  84
  85 void helper_raise_exception(uint32_t index)
  86 {
  87         env->exception_index = index;
  88         cpu_loop_exit();
  89 }
  90
  91 void helper_tlb_flush_pid(uint32_t pid)
  92 {
  93 #if !defined(CONFIG_USER_ONLY)
  94         pid &= 0xff;
  95         if (pid != (env->pregs[PR_PID] & 0xff))
  96                 cris_mmu_flush_pid(env, env->pregs[PR_PID]);
  97 #endif
  98 }
  99
 100 void helper_spc_write(uint32_t new_spc)
 101 {
 102 #if !defined(CONFIG_USER_ONLY)
 103         tlb_flush_page(env, env->pregs[PR_SPC]);
 104         tlb_flush_page(env, new_spc);
 105 #endif
 106 }
 107
 108 void helper_dump(uint32_t a0, uint32_t a1, uint32_t a2)
 109 {
 110         (fprintf(logfile, "%s: a0=%x a1=%x\n", __func__, a0, a1));
 111 }
 112
 113 /* Used by the tlb decoder.  */
 114 #define EXTRACT_FIELD(src, start, end) \
 115             (((src) >> start) & ((1 << (end - start + 1)) - 1))
 116
 117 void helper_movl_sreg_reg (uint32_t sreg, uint32_t reg)
 118 {
 119         uint32_t srs;
 120         srs = env->pregs[PR_SRS];
 121         srs &= 3;
 122         env->sregs[srs][sreg] = env->regs[reg];
 123
 124 #if !defined(CONFIG_USER_ONLY)
 125         if (srs == 1 || srs == 2) {
 126                 if (sreg == 6) {
 127                         /* Writes to tlb-hi write to mm_cause as a side
 128                            effect.  */
 129                         env->sregs[SFR_RW_MM_TLB_HI] = env->regs[reg];
 130                         env->sregs[SFR_R_MM_CAUSE] = env->regs[reg];
 131                 }
 132                 else if (sreg == 5) {
 133                         uint32_t set;
 134                         uint32_t idx;
 135                         uint32_t lo, hi;
 136                         uint32_t vaddr;
 137                         int tlb_v;
 138
 139                         idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
 140                         set >>= 4;
 141                         set &= 3;
 142
 143                         idx &= 15;
 144                         /* We've just made a write to tlb_lo.  */
 145                         lo = env->sregs[SFR_RW_MM_TLB_LO];
 146                         /* Writes are done via r_mm_cause.  */
 147                         hi = env->sregs[SFR_R_MM_CAUSE];
 148
 149                         vaddr = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].hi,
 150                                               13, 31);
 151                         vaddr <<= TARGET_PAGE_BITS;
 152                         tlb_v = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].lo,
 153                                             3, 3);
 154                         env->tlbsets[srs - 1][set][idx].lo = lo;
 155                         env->tlbsets[srs - 1][set][idx].hi = hi;
 156
 157                         D(fprintf(logfile,
 158                                   "tlb flush vaddr=%x v=%d pc=%x\n",
 159                                   vaddr, tlb_v, env->pc));
 160                         tlb_flush_page(env, vaddr);
 161                 }
 162         }
 163 #endif
 164 }
 165
 166 void helper_movl_reg_sreg (uint32_t reg, uint32_t sreg)
 167 {
 168         uint32_t srs;
 169         env->pregs[PR_SRS] &= 3;
 170         srs = env->pregs[PR_SRS];
 171
 172 #if !defined(CONFIG_USER_ONLY)
 173         if (srs == 1 || srs == 2)
 174         {
 175                 uint32_t set;
 176                 uint32_t idx;
 177                 uint32_t lo, hi;
 178
 179                 idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
 180                 set >>= 4;
 181                 set &= 3;
 182                 idx &= 15;
 183
 184                 /* Update the mirror regs.  */
 185                 hi = env->tlbsets[srs - 1][set][idx].hi;
 186                 lo = env->tlbsets[srs - 1][set][idx].lo;
 187                 env->sregs[SFR_RW_MM_TLB_HI] = hi;
 188                 env->sregs[SFR_RW_MM_TLB_LO] = lo;
 189         }
 190 #endif
 191         env->regs[reg] = env->sregs[srs][sreg];
 192 }
 193
 194 static void cris_ccs_rshift(CPUState *env)
 195 {
 196         uint32_t ccs;
 197
 198         /* Apply the ccs shift.  */
 199         ccs = env->pregs[PR_CCS];
 200         ccs = (ccs & 0xc0000000) | ((ccs & 0x0fffffff) >> 10);
 201         if (ccs & U_FLAG)
 202         {
 203                 /* Enter user mode.  */
 204                 env->ksp = env->regs[R_SP];
 205                 env->regs[R_SP] = env->pregs[PR_USP];
 206         }
 207
 208         env->pregs[PR_CCS] = ccs;
 209 }
 210
 211 void helper_rfe(void)
 212 {
 213         int rflag = env->pregs[PR_CCS] & R_FLAG;
 214
 215         D(fprintf(logfile, "rfe: erp=%x pid=%x ccs=%x btarget=%x\n",
 216                  env->pregs[PR_ERP], env->pregs[PR_PID],
 217                  env->pregs[PR_CCS],
 218                  env->btarget));
 219
 220         cris_ccs_rshift(env);
 221
 222         /* RFE sets the P_FLAG only if the R_FLAG is not set.  */
 223         if (!rflag)
 224                 env->pregs[PR_CCS] |= P_FLAG;
 225 }
 226
 227 void helper_rfn(void)
 228 {
 229         int rflag = env->pregs[PR_CCS] & R_FLAG;
 230
 231         D(fprintf(logfile, "rfn: erp=%x pid=%x ccs=%x btarget=%x\n",
 232                  env->pregs[PR_ERP], env->pregs[PR_PID],
 233                  env->pregs[PR_CCS],
 234                  env->btarget));
 235
 236         cris_ccs_rshift(env);
 237
 238         /* Set the P_FLAG only if the R_FLAG is not set.  */
 239         if (!rflag)
 240                 env->pregs[PR_CCS] |= P_FLAG;
 241
 242     /* Always set the M flag.  */
 243     env->pregs[PR_CCS] |= M_FLAG;
 244 }
 245
 246 static void evaluate_flags_writeback(uint32_t flags)
 247 {
 248         unsigned int x, z, mask;
 249
 250         /* Extended arithmetics, leave the z flag alone.  */
 251         x = env->cc_x;
 252         mask = env->cc_mask | X_FLAG;
 253         if (x) {
 254                 z = flags & Z_FLAG;
 255                 mask = mask & ~z;
 256         }
 257         flags &= mask;
 258
 259         /* all insn clear the x-flag except setf or clrf.  */
 260         env->pregs[PR_CCS] &= ~mask;
 261         env->pregs[PR_CCS] |= flags;
 262 }
 263
 264 void helper_evaluate_flags_muls(void)
 265 {
 266         uint32_t src;
 267         uint32_t dst;
 268         uint32_t res;
 269         uint32_t flags = 0;
 270         int64_t tmp;
 271         int32_t mof;
 272         int dneg;
 273
 274         src = env->cc_src;
 275         dst = env->cc_dest;
 276         res = env->cc_result;
 277
 278         dneg = ((int32_t)res) < 0;
 279
 280         mof = env->pregs[PR_MOF];
 281         tmp = mof;
 282         tmp <<= 32;
 283         tmp |= res;
 284         if (tmp == 0)
 285                 flags |= Z_FLAG;
 286         else if (tmp < 0)
 287                 flags |= N_FLAG;
 288         if ((dneg && mof != -1)
 289             || (!dneg && mof != 0))
 290                 flags |= V_FLAG;
 291         evaluate_flags_writeback(flags);
 292 }
 293
 294 void  helper_evaluate_flags_mulu(void)
 295 {
 296         uint32_t src;
 297         uint32_t dst;
 298         uint32_t res;
 299         uint32_t flags = 0;
 300         uint64_t tmp;
 301         uint32_t mof;
 302
 303         src = env->cc_src;
 304         dst = env->cc_dest;
 305         res = env->cc_result;
 306
 307         mof = env->pregs[PR_MOF];
 308         tmp = mof;
 309         tmp <<= 32;
 310         tmp |= res;
 311         if (tmp == 0)
 312                 flags |= Z_FLAG;
 313         else if (tmp >> 63)
 314                 flags |= N_FLAG;
 315         if (mof)
 316                 flags |= V_FLAG;
 317
 318         evaluate_flags_writeback(flags);
 319 }
 320
 321 void  helper_evaluate_flags_mcp(void)
 322 {
 323         uint32_t src;
 324         uint32_t dst;
 325         uint32_t res;
 326         uint32_t flags = 0;
 327
 328         src = env->cc_src & 0x80000000;
 329         dst = env->cc_dest & 0x80000000;
 330         res = env->cc_result;
 331
 332         if ((res & 0x80000000L) != 0L)
 333         {
 334                 flags |= N_FLAG;
 335                 if (!src && !dst)
 336                         flags |= V_FLAG;
 337                 else if (src & dst)
 338                         flags |= R_FLAG;
 339         }
 340         else
 341         {
 342                 if (res == 0L)
 343                         flags |= Z_FLAG;
 344                 if (src & dst)
 345                         flags |= V_FLAG;
 346                 if (dst | src)
 347                         flags |= R_FLAG;
 348         }
 349
 350         evaluate_flags_writeback(flags);
 351 }
 352
 353 void  helper_evaluate_flags_alu_4(void)
 354 {
 355         uint32_t src;
 356         uint32_t dst;
 357         uint32_t res;
 358         uint32_t flags = 0;
 359
 360         src = env->cc_src & 0x80000000;
 361         dst = env->cc_dest & 0x80000000;
 362         res = env->cc_result;
 363
 364         if ((res & 0x80000000L) != 0L)
 365         {
 366                 flags |= N_FLAG;
 367                 if (!src && !dst)
 368                         flags |= V_FLAG;
 369                 else if (src & dst)
 370                         flags |= C_FLAG;
 371         }
 372         else
 373         {
 374                 if (res == 0L)
 375                         flags |= Z_FLAG;
 376                 if (src & dst)
 377                         flags |= V_FLAG;
 378                 if (dst | src)
 379                         flags |= C_FLAG;
 380         }
 381
 382         evaluate_flags_writeback(flags);
 383 }
 384
 385 void  helper_evaluate_flags_sub_4(void)
 386 {
 387         uint32_t src;
 388         uint32_t dst;
 389         uint32_t res;
 390         uint32_t flags = 0;
 391
 392         src = (~env->cc_src) & 0x80000000;
 393         dst = env->cc_dest & 0x80000000;
 394         res = env->cc_result;
 395
 396         if ((res & 0x80000000L) != 0L)
 397         {
 398                 flags |= N_FLAG;
 399                 if (!src && !dst)
 400                         flags |= V_FLAG;
 401                 else if (src & dst)
 402                         flags |= C_FLAG;
 403         }
 404         else
 405         {
 406                 if (res == 0L)
 407                         flags |= Z_FLAG;
 408                 if (src & dst)
 409                         flags |= V_FLAG;
 410                 if (dst | src)
 411                         flags |= C_FLAG;
 412         }
 413
 414         flags ^= C_FLAG;
 415         evaluate_flags_writeback(flags);
 416 }
 417
 418 void  helper_evaluate_flags_move_4 (void)
 419 {
 420         uint32_t res;
 421         uint32_t flags = 0;
 422
 423         res = env->cc_result;
 424
 425         if ((int32_t)res < 0)
 426                 flags |= N_FLAG;
 427         else if (res == 0L)
 428                 flags |= Z_FLAG;
 429
 430         evaluate_flags_writeback(flags);
 431 }
 432 void  helper_evaluate_flags_move_2 (void)
 433 {
 434         uint32_t src;
 435         uint32_t flags = 0;
 436         uint16_t res;
 437
 438         src = env->cc_src;
 439         res = env->cc_result;
 440
 441         if ((int16_t)res < 0L)
 442                 flags |= N_FLAG;
 443         else if (res == 0)
 444                 flags |= Z_FLAG;
 445
 446         evaluate_flags_writeback(flags);
 447 }
 448
 449 /* TODO: This is expensive. We could split things up and only evaluate part of
 450    CCR on a need to know basis. For now, we simply re-evaluate everything.  */
 451 void helper_evaluate_flags (void)
 452 {
 453         uint32_t src;
 454         uint32_t dst;
 455         uint32_t res;
 456         uint32_t flags = 0;
 457
 458         src = env->cc_src;
 459         dst = env->cc_dest;
 460         res = env->cc_result;
 461
 462         if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 463                 src = ~src;
 464
 465         /* Now, evaluate the flags. This stuff is based on
 466            Per Zander's CRISv10 simulator.  */
 467         switch (env->cc_size)
 468         {
 469                 case 1:
 470                         if ((res & 0x80L) != 0L)
 471                         {
 472                                 flags |= N_FLAG;
 473                                 if (((src & 0x80L) == 0L)
 474                                     && ((dst & 0x80L) == 0L))
 475                                 {
 476                                         flags |= V_FLAG;
 477                                 }
 478                                 else if (((src & 0x80L) != 0L)
 479                                          && ((dst & 0x80L) != 0L))
 480                                 {
 481                                         flags |= C_FLAG;
 482                                 }
 483                         }
 484                         else
 485                         {
 486                                 if ((res & 0xFFL) == 0L)
 487                                 {
 488                                         flags |= Z_FLAG;
 489                                 }
 490                                 if (((src & 0x80L) != 0L)
 491                                     && ((dst & 0x80L) != 0L))
 492                                 {
 493                                         flags |= V_FLAG;
 494                                 }
 495                                 if ((dst & 0x80L) != 0L
 496                                     || (src & 0x80L) != 0L)
 497                                 {
 498                                         flags |= C_FLAG;
 499                                 }
 500                         }
 501                         break;
 502                 case 2:
 503                         if ((res & 0x8000L) != 0L)
 504                         {
 505                                 flags |= N_FLAG;
 506                                 if (((src & 0x8000L) == 0L)
 507                                     && ((dst & 0x8000L) == 0L))
 508                                 {
 509                                         flags |= V_FLAG;
 510                                 }
 511                                 else if (((src & 0x8000L) != 0L)
 512                                          && ((dst & 0x8000L) != 0L))
 513                                 {
 514                                         flags |= C_FLAG;
 515                                 }
 516                         }
 517                         else
 518                         {
 519                                 if ((res & 0xFFFFL) == 0L)
 520                                 {
 521                                         flags |= Z_FLAG;
 522                                 }
 523                                 if (((src & 0x8000L) != 0L)
 524                                     && ((dst & 0x8000L) != 0L))
 525                                 {
 526                                         flags |= V_FLAG;
 527                                 }
 528                                 if ((dst & 0x8000L) != 0L
 529                                     || (src & 0x8000L) != 0L)
 530                                 {
 531                                         flags |= C_FLAG;
 532                                 }
 533                         }
 534                         break;
 535                 case 4:
 536                         if ((res & 0x80000000L) != 0L)
 537                         {
 538                                 flags |= N_FLAG;
 539                                 if (((src & 0x80000000L) == 0L)
 540                                     && ((dst & 0x80000000L) == 0L))
 541                                 {
 542                                         flags |= V_FLAG;
 543                                 }
 544                                 else if (((src & 0x80000000L) != 0L) &&
 545                                          ((dst & 0x80000000L) != 0L))
 546                                 {
 547                                         flags |= C_FLAG;
 548                                 }
 549                         }
 550                         else
 551                         {
 552                                 if (res == 0L)
 553                                         flags |= Z_FLAG;
 554                                 if (((src & 0x80000000L) != 0L)
 555                                     && ((dst & 0x80000000L) != 0L))
 556                                         flags |= V_FLAG;
 557                                 if ((dst & 0x80000000L) != 0L
 558                                     || (src & 0x80000000L) != 0L)
 559                                         flags |= C_FLAG;
 560                         }
 561                         break;
 562                 default:
 563                         break;
 564         }
 565
 566         if (env->cc_op == CC_OP_SUB
 567             || env->cc_op == CC_OP_CMP) {
 568                 flags ^= C_FLAG;
 569         }
 570         evaluate_flags_writeback(flags);
 571 }
 572
 573 void helper_top_evaluate_flags(void)
 574 {
 575         switch (env->cc_op)
 576         {
 577                 case CC_OP_MCP:
 578                         helper_evaluate_flags_mcp();
 579                         break;
 580                 case CC_OP_MULS:
 581                         helper_evaluate_flags_muls();
 582                         break;
 583                 case CC_OP_MULU:
 584                         helper_evaluate_flags_mulu();
 585                         break;
 586                 case CC_OP_MOVE:
 587                 case CC_OP_AND:
 588                 case CC_OP_OR:
 589                 case CC_OP_XOR:
 590                 case CC_OP_ASR:
 591                 case CC_OP_LSR:
 592                 case CC_OP_LSL:
 593                         switch (env->cc_size)
 594                         {
 595                                 case 4:
 596                                         helper_evaluate_flags_move_4();
 597                                         break;
 598                                 case 2:
 599                                         helper_evaluate_flags_move_2();
 600                                         break;
 601                                 default:
 602                                         helper_evaluate_flags();
 603                                         break;
 604                         }
 605                         break;
 606                 case CC_OP_FLAGS:
 607                         /* live.  */
 608                         break;
 609                 case CC_OP_SUB:
 610                 case CC_OP_CMP:
 611                         if (env->cc_size == 4)
 612                                 helper_evaluate_flags_sub_4();
 613                         else
 614                                 helper_evaluate_flags();
 615                         break;
 616                 default:
 617                 {
 618                         switch (env->cc_size)
 619                         {
 620                                 case 4:
 621                                         helper_evaluate_flags_alu_4();
 622                                         break;
 623                                 default:
 624                                         helper_evaluate_flags();
 625                                         break;
 626                         }
 627                 }
 628                 break;
 629         }
 630 }