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         int x;
 249
 250         /* Extended arithmetics, leave the z flag alone.  */
 251         x = env->cc_x;
 252         if ((x || env->cc_op == CC_OP_ADDC)
 253             && flags & Z_FLAG)
 254                 env->cc_mask &= ~Z_FLAG;
 255
 256         /* all insn clear the x-flag except setf or clrf.  */
 257         env->pregs[PR_CCS] &= ~(env->cc_mask | X_FLAG);
 258         flags &= env->cc_mask;
 259         env->pregs[PR_CCS] |= flags;
 260 }
 261
 262 void helper_evaluate_flags_muls(void)
 263 {
 264         uint32_t src;
 265         uint32_t dst;
 266         uint32_t res;
 267         uint32_t flags = 0;
 268         int64_t tmp;
 269         int32_t mof;
 270         int dneg;
 271
 272         src = env->cc_src;
 273         dst = env->cc_dest;
 274         res = env->cc_result;
 275
 276         dneg = ((int32_t)res) < 0;
 277
 278         mof = env->pregs[PR_MOF];
 279         tmp = mof;
 280         tmp <<= 32;
 281         tmp |= res;
 282         if (tmp == 0)
 283                 flags |= Z_FLAG;
 284         else if (tmp < 0)
 285                 flags |= N_FLAG;
 286         if ((dneg && mof != -1)
 287             || (!dneg && mof != 0))
 288                 flags |= V_FLAG;
 289         evaluate_flags_writeback(flags);
 290 }
 291
 292 void  helper_evaluate_flags_mulu(void)
 293 {
 294         uint32_t src;
 295         uint32_t dst;
 296         uint32_t res;
 297         uint32_t flags = 0;
 298         uint64_t tmp;
 299         uint32_t mof;
 300
 301         src = env->cc_src;
 302         dst = env->cc_dest;
 303         res = env->cc_result;
 304
 305         mof = env->pregs[PR_MOF];
 306         tmp = mof;
 307         tmp <<= 32;
 308         tmp |= res;
 309         if (tmp == 0)
 310                 flags |= Z_FLAG;
 311         else if (tmp >> 63)
 312                 flags |= N_FLAG;
 313         if (mof)
 314                 flags |= V_FLAG;
 315
 316         evaluate_flags_writeback(flags);
 317 }
 318
 319 void  helper_evaluate_flags_mcp(void)
 320 {
 321         uint32_t src;
 322         uint32_t dst;
 323         uint32_t res;
 324         uint32_t flags = 0;
 325
 326         src = env->cc_src;
 327         dst = env->cc_dest;
 328         res = env->cc_result;
 329
 330         if ((res & 0x80000000L) != 0L)
 331         {
 332                 flags |= N_FLAG;
 333                 if (((src & 0x80000000L) == 0L)
 334                     && ((dst & 0x80000000L) == 0L))
 335                 {
 336                         flags |= V_FLAG;
 337                 }
 338                 else if (((src & 0x80000000L) != 0L) &&
 339                          ((dst & 0x80000000L) != 0L))
 340                 {
 341                         flags |= R_FLAG;
 342                 }
 343         }
 344         else
 345         {
 346                 if (res == 0L)
 347                         flags |= Z_FLAG;
 348                 if (((src & 0x80000000L) != 0L)
 349                     && ((dst & 0x80000000L) != 0L))
 350                         flags |= V_FLAG;
 351                 if ((dst & 0x80000000L) != 0L
 352                     || (src & 0x80000000L) != 0L)
 353                         flags |= R_FLAG;
 354         }
 355
 356         evaluate_flags_writeback(flags);
 357 }
 358
 359 void  helper_evaluate_flags_alu_4(void)
 360 {
 361         uint32_t src;
 362         uint32_t dst;
 363         uint32_t res;
 364         uint32_t flags = 0;
 365
 366         src = env->cc_src;
 367         dst = env->cc_dest;
 368
 369         /* Reconstruct the result.  */
 370         switch (env->cc_op)
 371         {
 372                 case CC_OP_SUB:
 373                         res = dst - src;
 374                         break;
 375                 case CC_OP_ADD:
 376                         res = dst + src;
 377                         break;
 378                 default:
 379                         res = env->cc_result;
 380                         break;
 381         }
 382
 383         if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 384                 src = ~src;
 385
 386         if ((res & 0x80000000L) != 0L)
 387         {
 388                 flags |= N_FLAG;
 389                 if (((src & 0x80000000L) == 0L)
 390                     && ((dst & 0x80000000L) == 0L))
 391                 {
 392                         flags |= V_FLAG;
 393                 }
 394                 else if (((src & 0x80000000L) != 0L) &&
 395                          ((dst & 0x80000000L) != 0L))
 396                 {
 397                         flags |= C_FLAG;
 398                 }
 399         }
 400         else
 401         {
 402                 if (res == 0L)
 403                         flags |= Z_FLAG;
 404                 if (((src & 0x80000000L) != 0L)
 405                     && ((dst & 0x80000000L) != 0L))
 406                         flags |= V_FLAG;
 407                 if ((dst & 0x80000000L) != 0L
 408                     || (src & 0x80000000L) != 0L)
 409                         flags |= C_FLAG;
 410         }
 411
 412         if (env->cc_op == CC_OP_SUB
 413             || env->cc_op == CC_OP_CMP) {
 414                 flags ^= C_FLAG;
 415         }
 416         evaluate_flags_writeback(flags);
 417 }
 418
 419 void  helper_evaluate_flags_move_4 (void)
 420 {
 421         uint32_t res;
 422         uint32_t flags = 0;
 423
 424         res = env->cc_result;
 425
 426         if ((int32_t)res < 0)
 427                 flags |= N_FLAG;
 428         else if (res == 0L)
 429                 flags |= Z_FLAG;
 430
 431         evaluate_flags_writeback(flags);
 432 }
 433 void  helper_evaluate_flags_move_2 (void)
 434 {
 435         uint32_t src;
 436         uint32_t flags = 0;
 437         uint16_t res;
 438
 439         src = env->cc_src;
 440         res = env->cc_result;
 441
 442         if ((int16_t)res < 0L)
 443                 flags |= N_FLAG;
 444         else if (res == 0)
 445                 flags |= Z_FLAG;
 446
 447         evaluate_flags_writeback(flags);
 448 }
 449
 450 /* TODO: This is expensive. We could split things up and only evaluate part of
 451    CCR on a need to know basis. For now, we simply re-evaluate everything.  */
 452 void helper_evaluate_flags (void)
 453 {
 454         uint32_t src;
 455         uint32_t dst;
 456         uint32_t res;
 457         uint32_t flags = 0;
 458
 459         src = env->cc_src;
 460         dst = env->cc_dest;
 461         res = env->cc_result;
 462
 463         if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 464                 src = ~src;
 465
 466         /* Now, evaluate the flags. This stuff is based on
 467            Per Zander's CRISv10 simulator.  */
 468         switch (env->cc_size)
 469         {
 470                 case 1:
 471                         if ((res & 0x80L) != 0L)
 472                         {
 473                                 flags |= N_FLAG;
 474                                 if (((src & 0x80L) == 0L)
 475                                     && ((dst & 0x80L) == 0L))
 476                                 {
 477                                         flags |= V_FLAG;
 478                                 }
 479                                 else if (((src & 0x80L) != 0L)
 480                                          && ((dst & 0x80L) != 0L))
 481                                 {
 482                                         flags |= C_FLAG;
 483                                 }
 484                         }
 485                         else
 486                         {
 487                                 if ((res & 0xFFL) == 0L)
 488                                 {
 489                                         flags |= Z_FLAG;
 490                                 }
 491                                 if (((src & 0x80L) != 0L)
 492                                     && ((dst & 0x80L) != 0L))
 493                                 {
 494                                         flags |= V_FLAG;
 495                                 }
 496                                 if ((dst & 0x80L) != 0L
 497                                     || (src & 0x80L) != 0L)
 498                                 {
 499                                         flags |= C_FLAG;
 500                                 }
 501                         }
 502                         break;
 503                 case 2:
 504                         if ((res & 0x8000L) != 0L)
 505                         {
 506                                 flags |= N_FLAG;
 507                                 if (((src & 0x8000L) == 0L)
 508                                     && ((dst & 0x8000L) == 0L))
 509                                 {
 510                                         flags |= V_FLAG;
 511                                 }
 512                                 else if (((src & 0x8000L) != 0L)
 513                                          && ((dst & 0x8000L) != 0L))
 514                                 {
 515                                         flags |= C_FLAG;
 516                                 }
 517                         }
 518                         else
 519                         {
 520                                 if ((res & 0xFFFFL) == 0L)
 521                                 {
 522                                         flags |= Z_FLAG;
 523                                 }
 524                                 if (((src & 0x8000L) != 0L)
 525                                     && ((dst & 0x8000L) != 0L))
 526                                 {
 527                                         flags |= V_FLAG;
 528                                 }
 529                                 if ((dst & 0x8000L) != 0L
 530                                     || (src & 0x8000L) != 0L)
 531                                 {
 532                                         flags |= C_FLAG;
 533                                 }
 534                         }
 535                         break;
 536                 case 4:
 537                         if ((res & 0x80000000L) != 0L)
 538                         {
 539                                 flags |= N_FLAG;
 540                                 if (((src & 0x80000000L) == 0L)
 541                                     && ((dst & 0x80000000L) == 0L))
 542                                 {
 543                                         flags |= V_FLAG;
 544                                 }
 545                                 else if (((src & 0x80000000L) != 0L) &&
 546                                          ((dst & 0x80000000L) != 0L))
 547                                 {
 548                                         flags |= C_FLAG;
 549                                 }
 550                         }
 551                         else
 552                         {
 553                                 if (res == 0L)
 554                                         flags |= Z_FLAG;
 555                                 if (((src & 0x80000000L) != 0L)
 556                                     && ((dst & 0x80000000L) != 0L))
 557                                         flags |= V_FLAG;
 558                                 if ((dst & 0x80000000L) != 0L
 559                                     || (src & 0x80000000L) != 0L)
 560                                         flags |= C_FLAG;
 561                         }
 562                         break;
 563                 default:
 564                         break;
 565         }
 566
 567         if (env->cc_op == CC_OP_SUB
 568             || env->cc_op == CC_OP_CMP) {
 569                 flags ^= C_FLAG;
 570         }
 571         evaluate_flags_writeback(flags);
 572 }
 573
 574 void helper_top_evaluate_flags(void)
 575 {
 576         switch (env->cc_op)
 577         {
 578                 case CC_OP_MCP:
 579                         helper_evaluate_flags_mcp();
 580                         break;
 581                 case CC_OP_MULS:
 582                         helper_evaluate_flags_muls();
 583                         break;
 584                 case CC_OP_MULU:
 585                         helper_evaluate_flags_mulu();
 586                         break;
 587                 case CC_OP_MOVE:
 588                 case CC_OP_AND:
 589                 case CC_OP_OR:
 590                 case CC_OP_XOR:
 591                 case CC_OP_ASR:
 592                 case CC_OP_LSR:
 593                 case CC_OP_LSL:
 594                         switch (env->cc_size)
 595                         {
 596                                 case 4:
 597                                         helper_evaluate_flags_move_4();
 598                                         break;
 599                                 case 2:
 600                                         helper_evaluate_flags_move_2();
 601                                         break;
 602                                 default:
 603                                         helper_evaluate_flags();
 604                                         break;
 605                         }
 606                         break;
 607                 case CC_OP_FLAGS:
 608                         /* live.  */
 609                         break;
 610                 default:
 611                 {
 612                         switch (env->cc_size)
 613                         {
 614                                 case 4:
 615                                         helper_evaluate_flags_alu_4();
 616                                         break;
 617                                 default:
 618                                         helper_evaluate_flags();
 619                                         break;
 620                         }
 621                 }
 622                 break;
 623         }
 624 }