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, NULL);
  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                         tlb_flush_page(env, vaddr);
 168                 }
 169         }
 170 #endif
 171 }
 172
 173 void helper_movl_reg_sreg (uint32_t reg, uint32_t sreg)
 174 {
 175         uint32_t srs;
 176         env->pregs[PR_SRS] &= 3;
 177         srs = env->pregs[PR_SRS];
 178
 179 #if !defined(CONFIG_USER_ONLY)
 180         if (srs == 1 || srs == 2)
 181         {
 182                 uint32_t set;
 183                 uint32_t idx;
 184                 uint32_t lo, hi;
 185
 186                 idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
 187                 set >>= 4;
 188                 set &= 3;
 189                 idx &= 15;
 190
 191                 /* Update the mirror regs.  */
 192                 hi = env->tlbsets[srs - 1][set][idx].hi;
 193                 lo = env->tlbsets[srs - 1][set][idx].lo;
 194                 env->sregs[SFR_RW_MM_TLB_HI] = hi;
 195                 env->sregs[SFR_RW_MM_TLB_LO] = lo;
 196         }
 197 #endif
 198         env->regs[reg] = env->sregs[srs][sreg];
 199 }
 200
 201 static void cris_ccs_rshift(CPUState *env)
 202 {
 203         uint32_t ccs;
 204
 205         /* Apply the ccs shift.  */
 206         ccs = env->pregs[PR_CCS];
 207         ccs = (ccs & 0xc0000000) | ((ccs & 0x0fffffff) >> 10);
 208         if (ccs & U_FLAG)
 209         {
 210                 /* Enter user mode.  */
 211                 env->ksp = env->regs[R_SP];
 212                 env->regs[R_SP] = env->pregs[PR_USP];
 213         }
 214
 215         env->pregs[PR_CCS] = ccs;
 216 }
 217
 218 void helper_rfe(void)
 219 {
 220         int rflag = env->pregs[PR_CCS] & R_FLAG;
 221
 222         D_LOG("rfe: erp=%x pid=%x ccs=%x btarget=%x\n",
 223                  env->pregs[PR_ERP], env->pregs[PR_PID],
 224                  env->pregs[PR_CCS],
 225                  env->btarget);
 226
 227         cris_ccs_rshift(env);
 228
 229         /* RFE sets the P_FLAG only if the R_FLAG is not set.  */
 230         if (!rflag)
 231                 env->pregs[PR_CCS] |= P_FLAG;
 232 }
 233
 234 void helper_rfn(void)
 235 {
 236         int rflag = env->pregs[PR_CCS] & R_FLAG;
 237
 238         D_LOG("rfn: erp=%x pid=%x ccs=%x btarget=%x\n",
 239                  env->pregs[PR_ERP], env->pregs[PR_PID],
 240                  env->pregs[PR_CCS],
 241                  env->btarget);
 242
 243         cris_ccs_rshift(env);
 244
 245         /* Set the P_FLAG only if the R_FLAG is not set.  */
 246         if (!rflag)
 247                 env->pregs[PR_CCS] |= P_FLAG;
 248
 249     /* Always set the M flag.  */
 250     env->pregs[PR_CCS] |= M_FLAG;
 251 }
 252
 253 uint32_t helper_lz(uint32_t t0)
 254 {
 255         return clz32(t0);
 256 }
 257
 258 uint32_t helper_btst(uint32_t t0, uint32_t t1, uint32_t ccs)
 259 {
 260         /* FIXME: clean this up.  */
 261
 262         /* des ref:
 263            The N flag is set according to the selected bit in the dest reg.
 264            The Z flag is set if the selected bit and all bits to the right are
 265            zero.
 266            The X flag is cleared.
 267            Other flags are left untouched.
 268            The destination reg is not affected.*/
 269         unsigned int fz, sbit, bset, mask, masked_t0;
 270
 271         sbit = t1 & 31;
 272         bset = !!(t0 & (1 << sbit));
 273         mask = sbit == 31 ? -1 : (1 << (sbit + 1)) - 1;
 274         masked_t0 = t0 & mask;
 275         fz = !(masked_t0 | bset);
 276
 277         /* Clear the X, N and Z flags.  */
 278         ccs = ccs & ~(X_FLAG | N_FLAG | Z_FLAG);
 279         if (env->pregs[PR_VR] < 32)
 280                 ccs &= ~(V_FLAG | C_FLAG);
 281         /* Set the N and Z flags accordingly.  */
 282         ccs |= (bset << 3) | (fz << 2);
 283         return ccs;
 284 }
 285
 286 static inline uint32_t evaluate_flags_writeback(uint32_t flags, uint32_t ccs)
 287 {
 288         unsigned int x, z, mask;
 289
 290         /* Extended arithmetics, leave the z flag alone.  */
 291         x = env->cc_x;
 292         mask = env->cc_mask | X_FLAG;
 293         if (x) {
 294                 z = flags & Z_FLAG;
 295                 mask = mask & ~z;
 296         }
 297         flags &= mask;
 298
 299         /* all insn clear the x-flag except setf or clrf.  */
 300         ccs &= ~mask;
 301         ccs |= flags;
 302         return ccs;
 303 }
 304
 305 uint32_t helper_evaluate_flags_muls(uint32_t ccs, uint32_t res, uint32_t mof)
 306 {
 307         uint32_t flags = 0;
 308         int64_t tmp;
 309         int dneg;
 310
 311         dneg = ((int32_t)res) < 0;
 312
 313         tmp = mof;
 314         tmp <<= 32;
 315         tmp |= res;
 316         if (tmp == 0)
 317                 flags |= Z_FLAG;
 318         else if (tmp < 0)
 319                 flags |= N_FLAG;
 320         if ((dneg && mof != -1)
 321             || (!dneg && mof != 0))
 322                 flags |= V_FLAG;
 323         return evaluate_flags_writeback(flags, ccs);
 324 }
 325
 326 uint32_t helper_evaluate_flags_mulu(uint32_t ccs, uint32_t res, uint32_t mof)
 327 {
 328         uint32_t flags = 0;
 329         uint64_t tmp;
 330
 331         tmp = mof;
 332         tmp <<= 32;
 333         tmp |= res;
 334         if (tmp == 0)
 335                 flags |= Z_FLAG;
 336         else if (tmp >> 63)
 337                 flags |= N_FLAG;
 338         if (mof)
 339                 flags |= V_FLAG;
 340
 341         return evaluate_flags_writeback(flags, ccs);
 342 }
 343
 344 uint32_t helper_evaluate_flags_mcp(uint32_t ccs,
 345                                    uint32_t src, uint32_t dst, uint32_t res)
 346 {
 347         uint32_t flags = 0;
 348
 349         src = src & 0x80000000;
 350         dst = dst & 0x80000000;
 351
 352         if ((res & 0x80000000L) != 0L)
 353         {
 354                 flags |= N_FLAG;
 355                 if (!src && !dst)
 356                         flags |= V_FLAG;
 357                 else if (src & dst)
 358                         flags |= R_FLAG;
 359         }
 360         else
 361         {
 362                 if (res == 0L)
 363                         flags |= Z_FLAG;
 364                 if (src & dst)
 365                         flags |= V_FLAG;
 366                 if (dst | src)
 367                         flags |= R_FLAG;
 368         }
 369
 370         return evaluate_flags_writeback(flags, ccs);
 371 }
 372
 373 uint32_t helper_evaluate_flags_alu_4(uint32_t ccs,
 374                                      uint32_t src, uint32_t dst, uint32_t res)
 375 {
 376         uint32_t flags = 0;
 377
 378         src = src & 0x80000000;
 379         dst = dst & 0x80000000;
 380
 381         if ((res & 0x80000000L) != 0L)
 382         {
 383                 flags |= N_FLAG;
 384                 if (!src && !dst)
 385                         flags |= V_FLAG;
 386                 else if (src & dst)
 387                         flags |= C_FLAG;
 388         }
 389         else
 390         {
 391                 if (res == 0L)
 392                         flags |= Z_FLAG;
 393                 if (src & dst)
 394                         flags |= V_FLAG;
 395                 if (dst | src)
 396                         flags |= C_FLAG;
 397         }
 398
 399         return evaluate_flags_writeback(flags, ccs);
 400 }
 401
 402 uint32_t helper_evaluate_flags_sub_4(uint32_t ccs,
 403                                      uint32_t src, uint32_t dst, uint32_t res)
 404 {
 405         uint32_t flags = 0;
 406
 407         src = (~src) & 0x80000000;
 408         dst = dst & 0x80000000;
 409
 410         if ((res & 0x80000000L) != 0L)
 411         {
 412                 flags |= N_FLAG;
 413                 if (!src && !dst)
 414                         flags |= V_FLAG;
 415                 else if (src & dst)
 416                         flags |= C_FLAG;
 417         }
 418         else
 419         {
 420                 if (res == 0L)
 421                         flags |= Z_FLAG;
 422                 if (src & dst)
 423                         flags |= V_FLAG;
 424                 if (dst | src)
 425                         flags |= C_FLAG;
 426         }
 427
 428         flags ^= C_FLAG;
 429         return evaluate_flags_writeback(flags, ccs);
 430 }
 431
 432 uint32_t helper_evaluate_flags_move_4(uint32_t ccs, uint32_t res)
 433 {
 434         uint32_t flags = 0;
 435
 436         if ((int32_t)res < 0)
 437                 flags |= N_FLAG;
 438         else if (res == 0L)
 439                 flags |= Z_FLAG;
 440
 441         return evaluate_flags_writeback(flags, ccs);
 442 }
 443 uint32_t helper_evaluate_flags_move_2(uint32_t ccs, uint32_t res)
 444 {
 445         uint32_t flags = 0;
 446
 447         if ((int16_t)res < 0L)
 448                 flags |= N_FLAG;
 449         else if (res == 0)
 450                 flags |= Z_FLAG;
 451
 452         return evaluate_flags_writeback(flags, ccs);
 453 }
 454
 455 /* TODO: This is expensive. We could split things up and only evaluate part of
 456    CCR on a need to know basis. For now, we simply re-evaluate everything.  */
 457 void  helper_evaluate_flags(void)
 458 {
 459         uint32_t src, dst, res;
 460         uint32_t flags = 0;
 461
 462         src = env->cc_src;
 463         dst = env->cc_dest;
 464         res = env->cc_result;
 465
 466         if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 467                 src = ~src;
 468
 469         /* Now, evaluate the flags. This stuff is based on
 470            Per Zander's CRISv10 simulator.  */
 471         switch (env->cc_size)
 472         {
 473                 case 1:
 474                         if ((res & 0x80L) != 0L)
 475                         {
 476                                 flags |= N_FLAG;
 477                                 if (((src & 0x80L) == 0L)
 478                                     && ((dst & 0x80L) == 0L))
 479                                 {
 480                                         flags |= V_FLAG;
 481                                 }
 482                                 else if (((src & 0x80L) != 0L)
 483                                          && ((dst & 0x80L) != 0L))
 484                                 {
 485                                         flags |= C_FLAG;
 486                                 }
 487                         }
 488                         else
 489                         {
 490                                 if ((res & 0xFFL) == 0L)
 491                                 {
 492                                         flags |= Z_FLAG;
 493                                 }
 494                                 if (((src & 0x80L) != 0L)
 495                                     && ((dst & 0x80L) != 0L))
 496                                 {
 497                                         flags |= V_FLAG;
 498                                 }
 499                                 if ((dst & 0x80L) != 0L
 500                                     || (src & 0x80L) != 0L)
 501                                 {
 502                                         flags |= C_FLAG;
 503                                 }
 504                         }
 505                         break;
 506                 case 2:
 507                         if ((res & 0x8000L) != 0L)
 508                         {
 509                                 flags |= N_FLAG;
 510                                 if (((src & 0x8000L) == 0L)
 511                                     && ((dst & 0x8000L) == 0L))
 512                                 {
 513                                         flags |= V_FLAG;
 514                                 }
 515                                 else if (((src & 0x8000L) != 0L)
 516                                          && ((dst & 0x8000L) != 0L))
 517                                 {
 518                                         flags |= C_FLAG;
 519                                 }
 520                         }
 521                         else
 522                         {
 523                                 if ((res & 0xFFFFL) == 0L)
 524                                 {
 525                                         flags |= Z_FLAG;
 526                                 }
 527                                 if (((src & 0x8000L) != 0L)
 528                                     && ((dst & 0x8000L) != 0L))
 529                                 {
 530                                         flags |= V_FLAG;
 531                                 }
 532                                 if ((dst & 0x8000L) != 0L
 533                                     || (src & 0x8000L) != 0L)
 534                                 {
 535                                         flags |= C_FLAG;
 536                                 }
 537                         }
 538                         break;
 539                 case 4:
 540                         if ((res & 0x80000000L) != 0L)
 541                         {
 542                                 flags |= N_FLAG;
 543                                 if (((src & 0x80000000L) == 0L)
 544                                     && ((dst & 0x80000000L) == 0L))
 545                                 {
 546                                         flags |= V_FLAG;
 547                                 }
 548                                 else if (((src & 0x80000000L) != 0L) &&
 549                                          ((dst & 0x80000000L) != 0L))
 550                                 {
 551                                         flags |= C_FLAG;
 552                                 }
 553                         }
 554                         else
 555                         {
 556                                 if (res == 0L)
 557                                         flags |= Z_FLAG;
 558                                 if (((src & 0x80000000L) != 0L)
 559                                     && ((dst & 0x80000000L) != 0L))
 560                                         flags |= V_FLAG;
 561                                 if ((dst & 0x80000000L) != 0L
 562                                     || (src & 0x80000000L) != 0L)
 563                                         flags |= C_FLAG;
 564                         }
 565                         break;
 566                 default:
 567                         break;
 568         }
 569
 570         if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 571                 flags ^= C_FLAG;
 572
 573         env->pregs[PR_CCS] = evaluate_flags_writeback(flags, env->pregs[PR_CCS]);
 574 }
 575
 576 void helper_top_evaluate_flags(void)
 577 {
 578         switch (env->cc_op)
 579         {
 580                 case CC_OP_MCP:
 581                         env->pregs[PR_CCS] = helper_evaluate_flags_mcp(
 582                                         env->pregs[PR_CCS], env->cc_src,
 583                                         env->cc_dest, env->cc_result);
 584                         break;
 585                 case CC_OP_MULS:
 586                         env->pregs[PR_CCS] = helper_evaluate_flags_muls(
 587                                         env->pregs[PR_CCS], env->cc_result,
 588                                         env->pregs[PR_MOF]);
 589                         break;
 590                 case CC_OP_MULU:
 591                         env->pregs[PR_CCS] = helper_evaluate_flags_mulu(
 592                                         env->pregs[PR_CCS], env->cc_result,
 593                                         env->pregs[PR_MOF]);
 594                         break;
 595                 case CC_OP_MOVE:
 596                 case CC_OP_AND:
 597                 case CC_OP_OR:
 598                 case CC_OP_XOR:
 599                 case CC_OP_ASR:
 600                 case CC_OP_LSR:
 601                 case CC_OP_LSL:
 602                 switch (env->cc_size)
 603                 {
 604                         case 4:
 605                                 env->pregs[PR_CCS] =
 606                                         helper_evaluate_flags_move_4(
 607                                                         env->pregs[PR_CCS],
 608                                                         env->cc_result);
 609                                 break;
 610                         case 2:
 611                                 env->pregs[PR_CCS] =
 612                                         helper_evaluate_flags_move_2(
 613                                                         env->pregs[PR_CCS],
 614                                                         env->cc_result);
 615                                 break;
 616                         default:
 617                                 helper_evaluate_flags();
 618                                 break;
 619                 }
 620                 break;
 621                 case CC_OP_FLAGS:
 622                         /* live.  */
 623                         break;
 624                 case CC_OP_SUB:
 625                 case CC_OP_CMP:
 626                         if (env->cc_size == 4)
 627                                 env->pregs[PR_CCS] =
 628                                         helper_evaluate_flags_sub_4(
 629                                                 env->pregs[PR_CCS],
 630                                                 env->cc_src, env->cc_dest,
 631                                                 env->cc_result);
 632                         else
 633                                 helper_evaluate_flags();
 634                         break;
 635                 default:
 636                 {
 637                         switch (env->cc_size)
 638                         {
 639                         case 4:
 640                                 env->pregs[PR_CCS] =
 641                                         helper_evaluate_flags_alu_4(
 642                                                 env->pregs[PR_CCS],
 643                                                 env->cc_src, env->cc_dest,
 644                                                 env->cc_result);
 645                                 break;
 646                         default:
 647                                 helper_evaluate_flags();
 648                                 break;
 649                         }
 650                 }
 651                 break;
 652         }
 653 }