LXR qemu/target-cris/op

   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 "cpu.h"
  22#include "mmu.h"
  23#include "exec/helper-proto.h"
  24#include "qemu/host-utils.h"
  25#include "exec/cpu_ldst.h"
  26
  27//#define CRIS_OP_HELPER_DEBUG
  28
  29
  30#ifdef CRIS_OP_HELPER_DEBUG
  31#define D(x) x
  32#define D_LOG(...) qemu_log(__VA_ARGS__)
  33#else
  34#define D(x)
  35#define D_LOG(...) do { } while (0)
  36#endif
  37
  38#if !defined(CONFIG_USER_ONLY)
  39/* Try to fill the TLB and return an exception if error. If retaddr is
  40   NULL, it means that the function was called in C code (i.e. not
  41   from generated code or from helper.c) */
  42void tlb_fill(CPUState *cs, target_ulong addr, int is_write, int mmu_idx,
  43              uintptr_t retaddr)
  44{
  45    CRISCPU *cpu = CRIS_CPU(cs);
  46    CPUCRISState *env = &cpu->env;
  47    int ret;
  48
  49    D_LOG("%s pc=%x tpc=%x ra=%p\n", __func__,
  50          env->pc, env->pregs[PR_EDA], (void *)retaddr);
  51    ret = cris_cpu_handle_mmu_fault(cs, addr, is_write, mmu_idx);
  52    if (unlikely(ret)) {
  53        if (retaddr) {
  54            /* now we have a real cpu fault */
  55            if (cpu_restore_state(cs, retaddr)) {
  56                /* Evaluate flags after retranslation.  */
  57                helper_top_evaluate_flags(env);
  58            }
  59        }
  60        cpu_loop_exit(cs);
  61    }
  62}
  63
  64#endif
  65
  66void helper_raise_exception(CPUCRISState *env, uint32_t index)
  67{
  68    CPUState *cs = CPU(cris_env_get_cpu(env));
  69
  70    cs->exception_index = index;
  71    cpu_loop_exit(cs);
  72}
  73
  74void helper_tlb_flush_pid(CPUCRISState *env, uint32_t pid)
  75{
  76#if !defined(CONFIG_USER_ONLY)
  77        pid &= 0xff;
  78        if (pid != (env->pregs[PR_PID] & 0xff))
  79                cris_mmu_flush_pid(env, env->pregs[PR_PID]);
  80#endif
  81}
  82
  83void helper_spc_write(CPUCRISState *env, uint32_t new_spc)
  84{
  85#if !defined(CONFIG_USER_ONLY)
  86    CRISCPU *cpu = cris_env_get_cpu(env);
  87    CPUState *cs = CPU(cpu);
  88
  89    tlb_flush_page(cs, env->pregs[PR_SPC]);
  90    tlb_flush_page(cs, new_spc);
  91#endif
  92}
  93
  94void helper_dump(uint32_t a0, uint32_t a1, uint32_t a2)
  95{
  96        qemu_log("%s: a0=%x a1=%x\n", __func__, a0, a1);
  97}
  98
  99/* Used by the tlb decoder.  */
 100#define EXTRACT_FIELD(src, start, end) \
 101            (((src) >> start) & ((1 << (end - start + 1)) - 1))
 102
 103void helper_movl_sreg_reg(CPUCRISState *env, uint32_t sreg, uint32_t reg)
 104{
 105#if !defined(CONFIG_USER_ONLY)
 106    CRISCPU *cpu = cris_env_get_cpu(env);
 107#endif
 108        uint32_t srs;
 109        srs = env->pregs[PR_SRS];
 110        srs &= 3;
 111        env->sregs[srs][sreg] = env->regs[reg];
 112
 113#if !defined(CONFIG_USER_ONLY)
 114        if (srs == 1 || srs == 2) {
 115                if (sreg == 6) {
 116                        /* Writes to tlb-hi write to mm_cause as a side 
 117                           effect.  */
 118                        env->sregs[SFR_RW_MM_TLB_HI] = env->regs[reg];
 119                        env->sregs[SFR_R_MM_CAUSE] = env->regs[reg];
 120                }
 121                else if (sreg == 5) {
 122                        uint32_t set;
 123                        uint32_t idx;
 124                        uint32_t lo, hi;
 125                        uint32_t vaddr;
 126                        int tlb_v;
 127
 128                        idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
 129                        set >>= 4;
 130                        set &= 3;
 131
 132                        idx &= 15;
 133                        /* We've just made a write to tlb_lo.  */
 134                        lo = env->sregs[SFR_RW_MM_TLB_LO];
 135                        /* Writes are done via r_mm_cause.  */
 136                        hi = env->sregs[SFR_R_MM_CAUSE];
 137
 138                        vaddr = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].hi,
 139                                              13, 31);
 140                        vaddr <<= TARGET_PAGE_BITS;
 141                        tlb_v = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].lo,
 142                                            3, 3);
 143                        env->tlbsets[srs - 1][set][idx].lo = lo;
 144                        env->tlbsets[srs - 1][set][idx].hi = hi;
 145
 146                        D_LOG("tlb flush vaddr=%x v=%d pc=%x\n", 
 147                                  vaddr, tlb_v, env->pc);
 148                        if (tlb_v) {
 149                tlb_flush_page(CPU(cpu), vaddr);
 150                        }
 151                }
 152        }
 153#endif
 154}
 155
 156void helper_movl_reg_sreg(CPUCRISState *env, uint32_t reg, uint32_t sreg)
 157{
 158        uint32_t srs;
 159        env->pregs[PR_SRS] &= 3;
 160        srs = env->pregs[PR_SRS];
 161        
 162#if !defined(CONFIG_USER_ONLY)
 163        if (srs == 1 || srs == 2)
 164        {
 165                uint32_t set;
 166                uint32_t idx;
 167                uint32_t lo, hi;
 168
 169                idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
 170                set >>= 4;
 171                set &= 3;
 172                idx &= 15;
 173
 174                /* Update the mirror regs.  */
 175                hi = env->tlbsets[srs - 1][set][idx].hi;
 176                lo = env->tlbsets[srs - 1][set][idx].lo;
 177                env->sregs[SFR_RW_MM_TLB_HI] = hi;
 178                env->sregs[SFR_RW_MM_TLB_LO] = lo;
 179        }
 180#endif
 181        env->regs[reg] = env->sregs[srs][sreg];
 182}
 183
 184static void cris_ccs_rshift(CPUCRISState *env)
 185{
 186        uint32_t ccs;
 187
 188        /* Apply the ccs shift.  */
 189        ccs = env->pregs[PR_CCS];
 190        ccs = (ccs & 0xc0000000) | ((ccs & 0x0fffffff) >> 10);
 191        if (ccs & U_FLAG)
 192        {
 193                /* Enter user mode.  */
 194                env->ksp = env->regs[R_SP];
 195                env->regs[R_SP] = env->pregs[PR_USP];
 196        }
 197
 198        env->pregs[PR_CCS] = ccs;
 199}
 200
 201void helper_rfe(CPUCRISState *env)
 202{
 203        int rflag = env->pregs[PR_CCS] & R_FLAG;
 204
 205        D_LOG("rfe: erp=%x pid=%x ccs=%x btarget=%x\n", 
 206                 env->pregs[PR_ERP], env->pregs[PR_PID],
 207                 env->pregs[PR_CCS],
 208                 env->btarget);
 209
 210        cris_ccs_rshift(env);
 211
 212        /* RFE sets the P_FLAG only if the R_FLAG is not set.  */
 213        if (!rflag)
 214                env->pregs[PR_CCS] |= P_FLAG;
 215}
 216
 217void helper_rfn(CPUCRISState *env)
 218{
 219        int rflag = env->pregs[PR_CCS] & R_FLAG;
 220
 221        D_LOG("rfn: erp=%x pid=%x ccs=%x btarget=%x\n", 
 222                 env->pregs[PR_ERP], env->pregs[PR_PID],
 223                 env->pregs[PR_CCS],
 224                 env->btarget);
 225
 226        cris_ccs_rshift(env);
 227
 228        /* Set the P_FLAG only if the R_FLAG is not set.  */
 229        if (!rflag)
 230                env->pregs[PR_CCS] |= P_FLAG;
 231
 232        /* Always set the M flag.  */
 233        env->pregs[PR_CCS] |= M_FLAG_V32;
 234}
 235
 236uint32_t helper_lz(uint32_t t0)
 237{
 238        return clz32(t0);
 239}
 240
 241uint32_t helper_btst(CPUCRISState *env, uint32_t t0, uint32_t t1, uint32_t ccs)
 242{
 243        /* FIXME: clean this up.  */
 244
 245        /* des ref:
 246           The N flag is set according to the selected bit in the dest reg.
 247           The Z flag is set if the selected bit and all bits to the right are
 248           zero.
 249           The X flag is cleared.
 250           Other flags are left untouched.
 251           The destination reg is not affected.*/
 252        unsigned int fz, sbit, bset, mask, masked_t0;
 253
 254        sbit = t1 & 31;
 255        bset = !!(t0 & (1 << sbit));
 256        mask = sbit == 31 ? -1 : (1 << (sbit + 1)) - 1;
 257        masked_t0 = t0 & mask;
 258        fz = !(masked_t0 | bset);
 259
 260        /* Clear the X, N and Z flags.  */
 261        ccs = ccs & ~(X_FLAG | N_FLAG | Z_FLAG);
 262        if (env->pregs[PR_VR] < 32)
 263                ccs &= ~(V_FLAG | C_FLAG);
 264        /* Set the N and Z flags accordingly.  */
 265        ccs |= (bset << 3) | (fz << 2);
 266        return ccs;
 267}
 268
 269static inline uint32_t evaluate_flags_writeback(CPUCRISState *env,
 270                                                uint32_t flags, uint32_t ccs)
 271{
 272        unsigned int x, z, mask;
 273
 274        /* Extended arithmetics, leave the z flag alone.  */
 275        x = env->cc_x;
 276        mask = env->cc_mask | X_FLAG;
 277        if (x) {
 278                z = flags & Z_FLAG;
 279                mask = mask & ~z;
 280        }
 281        flags &= mask;
 282
 283        /* all insn clear the x-flag except setf or clrf.  */
 284        ccs &= ~mask;
 285        ccs |= flags;
 286        return ccs;
 287}
 288
 289uint32_t helper_evaluate_flags_muls(CPUCRISState *env,
 290                                    uint32_t ccs, uint32_t res, uint32_t mof)
 291{
 292        uint32_t flags = 0;
 293        int64_t tmp;
 294        int dneg;
 295
 296        dneg = ((int32_t)res) < 0;
 297
 298        tmp = mof;
 299        tmp <<= 32;
 300        tmp |= res;
 301        if (tmp == 0)
 302                flags |= Z_FLAG;
 303        else if (tmp < 0)
 304                flags |= N_FLAG;
 305        if ((dneg && mof != -1)
 306            || (!dneg && mof != 0))
 307                flags |= V_FLAG;
 308        return evaluate_flags_writeback(env, flags, ccs);
 309}
 310
 311uint32_t helper_evaluate_flags_mulu(CPUCRISState *env,
 312                                    uint32_t ccs, uint32_t res, uint32_t mof)
 313{
 314        uint32_t flags = 0;
 315        uint64_t tmp;
 316
 317        tmp = mof;
 318        tmp <<= 32;
 319        tmp |= res;
 320        if (tmp == 0)
 321                flags |= Z_FLAG;
 322        else if (tmp >> 63)
 323                flags |= N_FLAG;
 324        if (mof)
 325                flags |= V_FLAG;
 326
 327        return evaluate_flags_writeback(env, flags, ccs);
 328}
 329
 330uint32_t helper_evaluate_flags_mcp(CPUCRISState *env, uint32_t ccs,
 331                                   uint32_t src, uint32_t dst, uint32_t res)
 332{
 333        uint32_t flags = 0;
 334
 335        src = src & 0x80000000;
 336        dst = dst & 0x80000000;
 337
 338        if ((res & 0x80000000L) != 0L)
 339        {
 340                flags |= N_FLAG;
 341                if (!src && !dst)
 342                        flags |= V_FLAG;
 343                else if (src & dst)
 344                        flags |= R_FLAG;
 345        }
 346        else
 347        {
 348                if (res == 0L)
 349                        flags |= Z_FLAG;
 350                if (src & dst) 
 351                        flags |= V_FLAG;
 352                if (dst | src) 
 353                        flags |= R_FLAG;
 354        }
 355
 356        return evaluate_flags_writeback(env, flags, ccs);
 357}
 358
 359uint32_t helper_evaluate_flags_alu_4(CPUCRISState *env, uint32_t ccs,
 360                                     uint32_t src, uint32_t dst, uint32_t res)
 361{
 362        uint32_t flags = 0;
 363
 364        src = src & 0x80000000;
 365        dst = dst & 0x80000000;
 366
 367        if ((res & 0x80000000L) != 0L)
 368        {
 369                flags |= N_FLAG;
 370                if (!src && !dst)
 371                        flags |= V_FLAG;
 372                else if (src & dst)
 373                        flags |= C_FLAG;
 374        }
 375        else
 376        {
 377                if (res == 0L)
 378                        flags |= Z_FLAG;
 379                if (src & dst) 
 380                        flags |= V_FLAG;
 381                if (dst | src) 
 382                        flags |= C_FLAG;
 383        }
 384
 385        return evaluate_flags_writeback(env, flags, ccs);
 386}
 387
 388uint32_t helper_evaluate_flags_sub_4(CPUCRISState *env, uint32_t ccs,
 389                                     uint32_t src, uint32_t dst, uint32_t res)
 390{
 391        uint32_t flags = 0;
 392
 393        src = (~src) & 0x80000000;
 394        dst = dst & 0x80000000;
 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        return evaluate_flags_writeback(env, flags, ccs);
 416}
 417
 418uint32_t helper_evaluate_flags_move_4(CPUCRISState *env,
 419                                      uint32_t ccs, uint32_t res)
 420{
 421        uint32_t flags = 0;
 422
 423        if ((int32_t)res < 0)
 424                flags |= N_FLAG;
 425        else if (res == 0L)
 426                flags |= Z_FLAG;
 427
 428        return evaluate_flags_writeback(env, flags, ccs);
 429}
 430uint32_t helper_evaluate_flags_move_2(CPUCRISState *env,
 431                                      uint32_t ccs, uint32_t res)
 432{
 433        uint32_t flags = 0;
 434
 435        if ((int16_t)res < 0L)
 436                flags |= N_FLAG;
 437        else if (res == 0)
 438                flags |= Z_FLAG;
 439
 440        return evaluate_flags_writeback(env, flags, ccs);
 441}
 442
 443/* TODO: This is expensive. We could split things up and only evaluate part of
 444   CCR on a need to know basis. For now, we simply re-evaluate everything.  */
 445void helper_evaluate_flags(CPUCRISState *env)
 446{
 447        uint32_t src, dst, res;
 448        uint32_t flags = 0;
 449
 450        src = env->cc_src;
 451        dst = env->cc_dest;
 452        res = env->cc_result;
 453
 454        if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 455                src = ~src;
 456
 457        /* Now, evaluate the flags. This stuff is based on
 458           Per Zander's CRISv10 simulator.  */
 459        switch (env->cc_size)
 460        {
 461                case 1:
 462                        if ((res & 0x80L) != 0L)
 463                        {
 464                                flags |= N_FLAG;
 465                                if (((src & 0x80L) == 0L)
 466                                    && ((dst & 0x80L) == 0L))
 467                                {
 468                                        flags |= V_FLAG;
 469                                }
 470                                else if (((src & 0x80L) != 0L)
 471                                         && ((dst & 0x80L) != 0L))
 472                                {
 473                                        flags |= C_FLAG;
 474                                }
 475                        }
 476                        else
 477                        {
 478                                if ((res & 0xFFL) == 0L)
 479                                {
 480                                        flags |= Z_FLAG;
 481                                }
 482                                if (((src & 0x80L) != 0L)
 483                                    && ((dst & 0x80L) != 0L))
 484                                {
 485                                        flags |= V_FLAG;
 486                                }
 487                                if ((dst & 0x80L) != 0L
 488                                    || (src & 0x80L) != 0L)
 489                                {
 490                                        flags |= C_FLAG;
 491                                }
 492                        }
 493                        break;
 494                case 2:
 495                        if ((res & 0x8000L) != 0L)
 496                        {
 497                                flags |= N_FLAG;
 498                                if (((src & 0x8000L) == 0L)
 499                                    && ((dst & 0x8000L) == 0L))
 500                                {
 501                                        flags |= V_FLAG;
 502                                }
 503                                else if (((src & 0x8000L) != 0L)
 504                                         && ((dst & 0x8000L) != 0L))
 505                                {
 506                                        flags |= C_FLAG;
 507                                }
 508                        }
 509                        else
 510                        {
 511                                if ((res & 0xFFFFL) == 0L)
 512                                {
 513                                        flags |= Z_FLAG;
 514                                }
 515                                if (((src & 0x8000L) != 0L)
 516                                    && ((dst & 0x8000L) != 0L))
 517                                {
 518                                        flags |= V_FLAG;
 519                                }
 520                                if ((dst & 0x8000L) != 0L
 521                                    || (src & 0x8000L) != 0L)
 522                                {
 523                                        flags |= C_FLAG;
 524                                }
 525                        }
 526                        break;
 527                case 4:
 528                        if ((res & 0x80000000L) != 0L)
 529                        {
 530                                flags |= N_FLAG;
 531                                if (((src & 0x80000000L) == 0L)
 532                                    && ((dst & 0x80000000L) == 0L))
 533                                {
 534                                        flags |= V_FLAG;
 535                                }
 536                                else if (((src & 0x80000000L) != 0L) &&
 537                                         ((dst & 0x80000000L) != 0L))
 538                                {
 539                                        flags |= C_FLAG;
 540                                }
 541                        }
 542                        else
 543                        {
 544                                if (res == 0L)
 545                                        flags |= Z_FLAG;
 546                                if (((src & 0x80000000L) != 0L)
 547                                    && ((dst & 0x80000000L) != 0L))
 548                                        flags |= V_FLAG;
 549                                if ((dst & 0x80000000L) != 0L
 550                                    || (src & 0x80000000L) != 0L)
 551                                        flags |= C_FLAG;
 552                        }
 553                        break;
 554                default:
 555                        break;
 556        }
 557
 558        if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 559                flags ^= C_FLAG;
 560
 561        env->pregs[PR_CCS] = evaluate_flags_writeback(env, flags,
 562                                                      env->pregs[PR_CCS]);
 563}
 564
 565void helper_top_evaluate_flags(CPUCRISState *env)
 566{
 567        switch (env->cc_op)
 568        {
 569                case CC_OP_MCP:
 570                        env->pregs[PR_CCS] = helper_evaluate_flags_mcp(env,
 571                                        env->pregs[PR_CCS], env->cc_src,
 572                                        env->cc_dest, env->cc_result);
 573                        break;
 574                case CC_OP_MULS:
 575                        env->pregs[PR_CCS] = helper_evaluate_flags_muls(env,
 576                                        env->pregs[PR_CCS], env->cc_result,
 577                                        env->pregs[PR_MOF]);
 578                        break;
 579                case CC_OP_MULU:
 580                        env->pregs[PR_CCS] = helper_evaluate_flags_mulu(env,
 581                                        env->pregs[PR_CCS], env->cc_result,
 582                                        env->pregs[PR_MOF]);
 583                        break;
 584                case CC_OP_MOVE:
 585                case CC_OP_AND:
 586                case CC_OP_OR:
 587                case CC_OP_XOR:
 588                case CC_OP_ASR:
 589                case CC_OP_LSR:
 590                case CC_OP_LSL:
 591                switch (env->cc_size)
 592                {
 593                        case 4:
 594                                env->pregs[PR_CCS] =
 595                                        helper_evaluate_flags_move_4(env,
 596                                                        env->pregs[PR_CCS],
 597                                                        env->cc_result);
 598                                break;
 599                        case 2:
 600                                env->pregs[PR_CCS] =
 601                                        helper_evaluate_flags_move_2(env,
 602                                                        env->pregs[PR_CCS],
 603                                                        env->cc_result);
 604                                break;
 605                        default:
 606                                helper_evaluate_flags(env);
 607                                break;
 608                }
 609                break;
 610                case CC_OP_FLAGS:
 611                        /* live.  */
 612                        break;
 613                case CC_OP_SUB:
 614                case CC_OP_CMP:
 615                        if (env->cc_size == 4)
 616                                env->pregs[PR_CCS] =
 617                                        helper_evaluate_flags_sub_4(env,
 618                                                env->pregs[PR_CCS],
 619                                                env->cc_src, env->cc_dest,
 620                                                env->cc_result);
 621                        else
 622                                helper_evaluate_flags(env);
 623                        break;
 624                default:
 625                {
 626                        switch (env->cc_size)
 627                        {
 628                        case 4:
 629                                env->pregs[PR_CCS] =
 630                                        helper_evaluate_flags_alu_4(env,
 631                                                env->pregs[PR_CCS],
 632                                                env->cc_src, env->cc_dest,
 633                                                env->cc_result);
 634                                break;
 635                        default:
 636                                helper_evaluate_flags(env);
 637                                break;
 638                        }
 639                }
 640                break;
 641        }
 642}
 643