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 "qemu/osdep.h"
  22#include "cpu.h"
  23#include "mmu.h"
  24#include "exec/helper-proto.h"
  25#include "qemu/host-utils.h"
  26#include "exec/exec-all.h"
  27#include "exec/cpu_ldst.h"
  28
  29//#define CRIS_OP_HELPER_DEBUG
  30
  31
  32#ifdef CRIS_OP_HELPER_DEBUG
  33#define D(x) x
  34#define D_LOG(...) qemu_log(__VA_ARGS__)
  35#else
  36#define D(x)
  37#define D_LOG(...) do { } while (0)
  38#endif
  39
  40#if !defined(CONFIG_USER_ONLY)
  41/* Try to fill the TLB and return an exception if error. If retaddr is
  42   NULL, it means that the function was called in C code (i.e. not
  43   from generated code or from helper.c) */
  44void tlb_fill(CPUState *cs, target_ulong addr, int size,
  45              MMUAccessType access_type, int mmu_idx, uintptr_t retaddr)
  46{
  47    CRISCPU *cpu = CRIS_CPU(cs);
  48    CPUCRISState *env = &cpu->env;
  49    int ret;
  50
  51    D_LOG("%s pc=%x tpc=%x ra=%p\n", __func__,
  52          env->pc, env->pregs[PR_EDA], (void *)retaddr);
  53    ret = cris_cpu_handle_mmu_fault(cs, addr, size, access_type, mmu_idx);
  54    if (unlikely(ret)) {
  55        if (retaddr) {
  56            /* now we have a real cpu fault */
  57            if (cpu_restore_state(cs, retaddr, true)) {
  58                /* Evaluate flags after retranslation. */
  59                helper_top_evaluate_flags(env);
  60            }
  61        }
  62        cpu_loop_exit(cs);
  63    }
  64}
  65
  66#endif
  67
  68void helper_raise_exception(CPUCRISState *env, uint32_t index)
  69{
  70    CPUState *cs = CPU(cris_env_get_cpu(env));
  71
  72    cs->exception_index = index;
  73    cpu_loop_exit(cs);
  74}
  75
  76void helper_tlb_flush_pid(CPUCRISState *env, uint32_t pid)
  77{
  78#if !defined(CONFIG_USER_ONLY)
  79        pid &= 0xff;
  80        if (pid != (env->pregs[PR_PID] & 0xff))
  81                cris_mmu_flush_pid(env, env->pregs[PR_PID]);
  82#endif
  83}
  84
  85void helper_spc_write(CPUCRISState *env, uint32_t new_spc)
  86{
  87#if !defined(CONFIG_USER_ONLY)
  88    CRISCPU *cpu = cris_env_get_cpu(env);
  89    CPUState *cs = CPU(cpu);
  90
  91    tlb_flush_page(cs, env->pregs[PR_SPC]);
  92    tlb_flush_page(cs, new_spc);
  93#endif
  94}
  95
  96/* Used by the tlb decoder.  */
  97#define EXTRACT_FIELD(src, start, end) \
  98            (((src) >> start) & ((1 << (end - start + 1)) - 1))
  99
 100void helper_movl_sreg_reg(CPUCRISState *env, uint32_t sreg, uint32_t reg)
 101{
 102#if !defined(CONFIG_USER_ONLY)
 103    CRISCPU *cpu = cris_env_get_cpu(env);
 104#endif
 105        uint32_t srs;
 106        srs = env->pregs[PR_SRS];
 107        srs &= 3;
 108        env->sregs[srs][sreg] = env->regs[reg];
 109
 110#if !defined(CONFIG_USER_ONLY)
 111        if (srs == 1 || srs == 2) {
 112                if (sreg == 6) {
 113                        /* Writes to tlb-hi write to mm_cause as a side 
 114                           effect.  */
 115                        env->sregs[SFR_RW_MM_TLB_HI] = env->regs[reg];
 116                        env->sregs[SFR_R_MM_CAUSE] = env->regs[reg];
 117                }
 118                else if (sreg == 5) {
 119                        uint32_t set;
 120                        uint32_t idx;
 121                        uint32_t lo, hi;
 122                        uint32_t vaddr;
 123                        int tlb_v;
 124
 125                        idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
 126                        set >>= 4;
 127                        set &= 3;
 128
 129                        idx &= 15;
 130                        /* We've just made a write to tlb_lo.  */
 131                        lo = env->sregs[SFR_RW_MM_TLB_LO];
 132                        /* Writes are done via r_mm_cause.  */
 133                        hi = env->sregs[SFR_R_MM_CAUSE];
 134
 135                        vaddr = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].hi,
 136                                              13, 31);
 137                        vaddr <<= TARGET_PAGE_BITS;
 138                        tlb_v = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].lo,
 139                                            3, 3);
 140                        env->tlbsets[srs - 1][set][idx].lo = lo;
 141                        env->tlbsets[srs - 1][set][idx].hi = hi;
 142
 143                        D_LOG("tlb flush vaddr=%x v=%d pc=%x\n", 
 144                                  vaddr, tlb_v, env->pc);
 145                        if (tlb_v) {
 146                tlb_flush_page(CPU(cpu), vaddr);
 147                        }
 148                }
 149        }
 150#endif
 151}
 152
 153void helper_movl_reg_sreg(CPUCRISState *env, uint32_t reg, uint32_t sreg)
 154{
 155        uint32_t srs;
 156        env->pregs[PR_SRS] &= 3;
 157        srs = env->pregs[PR_SRS];
 158        
 159#if !defined(CONFIG_USER_ONLY)
 160        if (srs == 1 || srs == 2)
 161        {
 162                uint32_t set;
 163                uint32_t idx;
 164                uint32_t lo, hi;
 165
 166                idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
 167                set >>= 4;
 168                set &= 3;
 169                idx &= 15;
 170
 171                /* Update the mirror regs.  */
 172                hi = env->tlbsets[srs - 1][set][idx].hi;
 173                lo = env->tlbsets[srs - 1][set][idx].lo;
 174                env->sregs[SFR_RW_MM_TLB_HI] = hi;
 175                env->sregs[SFR_RW_MM_TLB_LO] = lo;
 176        }
 177#endif
 178        env->regs[reg] = env->sregs[srs][sreg];
 179}
 180
 181static void cris_ccs_rshift(CPUCRISState *env)
 182{
 183        uint32_t ccs;
 184
 185        /* Apply the ccs shift.  */
 186        ccs = env->pregs[PR_CCS];
 187        ccs = (ccs & 0xc0000000) | ((ccs & 0x0fffffff) >> 10);
 188        if (ccs & U_FLAG)
 189        {
 190                /* Enter user mode.  */
 191                env->ksp = env->regs[R_SP];
 192                env->regs[R_SP] = env->pregs[PR_USP];
 193        }
 194
 195        env->pregs[PR_CCS] = ccs;
 196}
 197
 198void helper_rfe(CPUCRISState *env)
 199{
 200        int rflag = env->pregs[PR_CCS] & R_FLAG;
 201
 202        D_LOG("rfe: erp=%x pid=%x ccs=%x btarget=%x\n", 
 203                 env->pregs[PR_ERP], env->pregs[PR_PID],
 204                 env->pregs[PR_CCS],
 205                 env->btarget);
 206
 207        cris_ccs_rshift(env);
 208
 209        /* RFE sets the P_FLAG only if the R_FLAG is not set.  */
 210        if (!rflag)
 211                env->pregs[PR_CCS] |= P_FLAG;
 212}
 213
 214void helper_rfn(CPUCRISState *env)
 215{
 216        int rflag = env->pregs[PR_CCS] & R_FLAG;
 217
 218        D_LOG("rfn: erp=%x pid=%x ccs=%x btarget=%x\n", 
 219                 env->pregs[PR_ERP], env->pregs[PR_PID],
 220                 env->pregs[PR_CCS],
 221                 env->btarget);
 222
 223        cris_ccs_rshift(env);
 224
 225        /* Set the P_FLAG only if the R_FLAG is not set.  */
 226        if (!rflag)
 227                env->pregs[PR_CCS] |= P_FLAG;
 228
 229        /* Always set the M flag.  */
 230        env->pregs[PR_CCS] |= M_FLAG_V32;
 231}
 232
 233uint32_t helper_btst(CPUCRISState *env, uint32_t t0, uint32_t t1, uint32_t ccs)
 234{
 235        /* FIXME: clean this up.  */
 236
 237        /* des ref:
 238           The N flag is set according to the selected bit in the dest reg.
 239           The Z flag is set if the selected bit and all bits to the right are
 240           zero.
 241           The X flag is cleared.
 242           Other flags are left untouched.
 243           The destination reg is not affected.*/
 244        unsigned int fz, sbit, bset, mask, masked_t0;
 245
 246        sbit = t1 & 31;
 247        bset = !!(t0 & (1 << sbit));
 248        mask = sbit == 31 ? -1 : (1 << (sbit + 1)) - 1;
 249        masked_t0 = t0 & mask;
 250        fz = !(masked_t0 | bset);
 251
 252        /* Clear the X, N and Z flags.  */
 253        ccs = ccs & ~(X_FLAG | N_FLAG | Z_FLAG);
 254        if (env->pregs[PR_VR] < 32)
 255                ccs &= ~(V_FLAG | C_FLAG);
 256        /* Set the N and Z flags accordingly.  */
 257        ccs |= (bset << 3) | (fz << 2);
 258        return ccs;
 259}
 260
 261static inline uint32_t evaluate_flags_writeback(CPUCRISState *env,
 262                                                uint32_t flags, uint32_t ccs)
 263{
 264        unsigned int x, z, mask;
 265
 266        /* Extended arithmetics, leave the z flag alone.  */
 267        x = env->cc_x;
 268        mask = env->cc_mask | X_FLAG;
 269        if (x) {
 270                z = flags & Z_FLAG;
 271                mask = mask & ~z;
 272        }
 273        flags &= mask;
 274
 275        /* all insn clear the x-flag except setf or clrf.  */
 276        ccs &= ~mask;
 277        ccs |= flags;
 278        return ccs;
 279}
 280
 281uint32_t helper_evaluate_flags_muls(CPUCRISState *env,
 282                                    uint32_t ccs, uint32_t res, uint32_t mof)
 283{
 284        uint32_t flags = 0;
 285        int64_t tmp;
 286        int dneg;
 287
 288        dneg = ((int32_t)res) < 0;
 289
 290        tmp = mof;
 291        tmp <<= 32;
 292        tmp |= res;
 293        if (tmp == 0)
 294                flags |= Z_FLAG;
 295        else if (tmp < 0)
 296                flags |= N_FLAG;
 297        if ((dneg && mof != -1)
 298            || (!dneg && mof != 0))
 299                flags |= V_FLAG;
 300        return evaluate_flags_writeback(env, flags, ccs);
 301}
 302
 303uint32_t helper_evaluate_flags_mulu(CPUCRISState *env,
 304                                    uint32_t ccs, uint32_t res, uint32_t mof)
 305{
 306        uint32_t flags = 0;
 307        uint64_t tmp;
 308
 309        tmp = mof;
 310        tmp <<= 32;
 311        tmp |= res;
 312        if (tmp == 0)
 313                flags |= Z_FLAG;
 314        else if (tmp >> 63)
 315                flags |= N_FLAG;
 316        if (mof)
 317                flags |= V_FLAG;
 318
 319        return evaluate_flags_writeback(env, flags, ccs);
 320}
 321
 322uint32_t helper_evaluate_flags_mcp(CPUCRISState *env, uint32_t ccs,
 323                                   uint32_t src, uint32_t dst, uint32_t res)
 324{
 325        uint32_t flags = 0;
 326
 327        src = src & 0x80000000;
 328        dst = dst & 0x80000000;
 329
 330        if ((res & 0x80000000L) != 0L)
 331        {
 332                flags |= N_FLAG;
 333                if (!src && !dst)
 334                        flags |= V_FLAG;
 335                else if (src & dst)
 336                        flags |= R_FLAG;
 337        }
 338        else
 339        {
 340                if (res == 0L)
 341                        flags |= Z_FLAG;
 342                if (src & dst) 
 343                        flags |= V_FLAG;
 344                if (dst | src) 
 345                        flags |= R_FLAG;
 346        }
 347
 348        return evaluate_flags_writeback(env, flags, ccs);
 349}
 350
 351uint32_t helper_evaluate_flags_alu_4(CPUCRISState *env, uint32_t ccs,
 352                                     uint32_t src, uint32_t dst, uint32_t res)
 353{
 354        uint32_t flags = 0;
 355
 356        src = src & 0x80000000;
 357        dst = dst & 0x80000000;
 358
 359        if ((res & 0x80000000L) != 0L)
 360        {
 361                flags |= N_FLAG;
 362                if (!src && !dst)
 363                        flags |= V_FLAG;
 364                else if (src & dst)
 365                        flags |= C_FLAG;
 366        }
 367        else
 368        {
 369                if (res == 0L)
 370                        flags |= Z_FLAG;
 371                if (src & dst) 
 372                        flags |= V_FLAG;
 373                if (dst | src) 
 374                        flags |= C_FLAG;
 375        }
 376
 377        return evaluate_flags_writeback(env, flags, ccs);
 378}
 379
 380uint32_t helper_evaluate_flags_sub_4(CPUCRISState *env, uint32_t ccs,
 381                                     uint32_t src, uint32_t dst, uint32_t res)
 382{
 383        uint32_t flags = 0;
 384
 385        src = (~src) & 0x80000000;
 386        dst = dst & 0x80000000;
 387
 388        if ((res & 0x80000000L) != 0L)
 389        {
 390                flags |= N_FLAG;
 391                if (!src && !dst)
 392                        flags |= V_FLAG;
 393                else if (src & dst)
 394                        flags |= C_FLAG;
 395        }
 396        else
 397        {
 398                if (res == 0L)
 399                        flags |= Z_FLAG;
 400                if (src & dst) 
 401                        flags |= V_FLAG;
 402                if (dst | src) 
 403                        flags |= C_FLAG;
 404        }
 405
 406        flags ^= C_FLAG;
 407        return evaluate_flags_writeback(env, flags, ccs);
 408}
 409
 410uint32_t helper_evaluate_flags_move_4(CPUCRISState *env,
 411                                      uint32_t ccs, uint32_t res)
 412{
 413        uint32_t flags = 0;
 414
 415        if ((int32_t)res < 0)
 416                flags |= N_FLAG;
 417        else if (res == 0L)
 418                flags |= Z_FLAG;
 419
 420        return evaluate_flags_writeback(env, flags, ccs);
 421}
 422uint32_t helper_evaluate_flags_move_2(CPUCRISState *env,
 423                                      uint32_t ccs, uint32_t res)
 424{
 425        uint32_t flags = 0;
 426
 427        if ((int16_t)res < 0L)
 428                flags |= N_FLAG;
 429        else if (res == 0)
 430                flags |= Z_FLAG;
 431
 432        return evaluate_flags_writeback(env, flags, ccs);
 433}
 434
 435/* TODO: This is expensive. We could split things up and only evaluate part of
 436   CCR on a need to know basis. For now, we simply re-evaluate everything.  */
 437void helper_evaluate_flags(CPUCRISState *env)
 438{
 439        uint32_t src, dst, res;
 440        uint32_t flags = 0;
 441
 442        src = env->cc_src;
 443        dst = env->cc_dest;
 444        res = env->cc_result;
 445
 446        if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 447                src = ~src;
 448
 449        /* Now, evaluate the flags. This stuff is based on
 450           Per Zander's CRISv10 simulator.  */
 451        switch (env->cc_size)
 452        {
 453                case 1:
 454                        if ((res & 0x80L) != 0L)
 455                        {
 456                                flags |= N_FLAG;
 457                                if (((src & 0x80L) == 0L)
 458                                    && ((dst & 0x80L) == 0L))
 459                                {
 460                                        flags |= V_FLAG;
 461                                }
 462                                else if (((src & 0x80L) != 0L)
 463                                         && ((dst & 0x80L) != 0L))
 464                                {
 465                                        flags |= C_FLAG;
 466                                }
 467                        }
 468                        else
 469                        {
 470                                if ((res & 0xFFL) == 0L)
 471                                {
 472                                        flags |= Z_FLAG;
 473                                }
 474                                if (((src & 0x80L) != 0L)
 475                                    && ((dst & 0x80L) != 0L))
 476                                {
 477                                        flags |= V_FLAG;
 478                                }
 479                                if ((dst & 0x80L) != 0L
 480                                    || (src & 0x80L) != 0L)
 481                                {
 482                                        flags |= C_FLAG;
 483                                }
 484                        }
 485                        break;
 486                case 2:
 487                        if ((res & 0x8000L) != 0L)
 488                        {
 489                                flags |= N_FLAG;
 490                                if (((src & 0x8000L) == 0L)
 491                                    && ((dst & 0x8000L) == 0L))
 492                                {
 493                                        flags |= V_FLAG;
 494                                }
 495                                else if (((src & 0x8000L) != 0L)
 496                                         && ((dst & 0x8000L) != 0L))
 497                                {
 498                                        flags |= C_FLAG;
 499                                }
 500                        }
 501                        else
 502                        {
 503                                if ((res & 0xFFFFL) == 0L)
 504                                {
 505                                        flags |= Z_FLAG;
 506                                }
 507                                if (((src & 0x8000L) != 0L)
 508                                    && ((dst & 0x8000L) != 0L))
 509                                {
 510                                        flags |= V_FLAG;
 511                                }
 512                                if ((dst & 0x8000L) != 0L
 513                                    || (src & 0x8000L) != 0L)
 514                                {
 515                                        flags |= C_FLAG;
 516                                }
 517                        }
 518                        break;
 519                case 4:
 520                        if ((res & 0x80000000L) != 0L)
 521                        {
 522                                flags |= N_FLAG;
 523                                if (((src & 0x80000000L) == 0L)
 524                                    && ((dst & 0x80000000L) == 0L))
 525                                {
 526                                        flags |= V_FLAG;
 527                                }
 528                                else if (((src & 0x80000000L) != 0L) &&
 529                                         ((dst & 0x80000000L) != 0L))
 530                                {
 531                                        flags |= C_FLAG;
 532                                }
 533                        }
 534                        else
 535                        {
 536                                if (res == 0L)
 537                                        flags |= Z_FLAG;
 538                                if (((src & 0x80000000L) != 0L)
 539                                    && ((dst & 0x80000000L) != 0L))
 540                                        flags |= V_FLAG;
 541                                if ((dst & 0x80000000L) != 0L
 542                                    || (src & 0x80000000L) != 0L)
 543                                        flags |= C_FLAG;
 544                        }
 545                        break;
 546                default:
 547                        break;
 548        }
 549
 550        if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 551                flags ^= C_FLAG;
 552
 553        env->pregs[PR_CCS] = evaluate_flags_writeback(env, flags,
 554                                                      env->pregs[PR_CCS]);
 555}
 556
 557void helper_top_evaluate_flags(CPUCRISState *env)
 558{
 559        switch (env->cc_op)
 560        {
 561                case CC_OP_MCP:
 562                        env->pregs[PR_CCS] = helper_evaluate_flags_mcp(env,
 563                                        env->pregs[PR_CCS], env->cc_src,
 564                                        env->cc_dest, env->cc_result);
 565                        break;
 566                case CC_OP_MULS:
 567                        env->pregs[PR_CCS] = helper_evaluate_flags_muls(env,
 568                                        env->pregs[PR_CCS], env->cc_result,
 569                                        env->pregs[PR_MOF]);
 570                        break;
 571                case CC_OP_MULU:
 572                        env->pregs[PR_CCS] = helper_evaluate_flags_mulu(env,
 573                                        env->pregs[PR_CCS], env->cc_result,
 574                                        env->pregs[PR_MOF]);
 575                        break;
 576                case CC_OP_MOVE:
 577                case CC_OP_AND:
 578                case CC_OP_OR:
 579                case CC_OP_XOR:
 580                case CC_OP_ASR:
 581                case CC_OP_LSR:
 582                case CC_OP_LSL:
 583                switch (env->cc_size)
 584                {
 585                        case 4:
 586                                env->pregs[PR_CCS] =
 587                                        helper_evaluate_flags_move_4(env,
 588                                                        env->pregs[PR_CCS],
 589                                                        env->cc_result);
 590                                break;
 591                        case 2:
 592                                env->pregs[PR_CCS] =
 593                                        helper_evaluate_flags_move_2(env,
 594                                                        env->pregs[PR_CCS],
 595                                                        env->cc_result);
 596                                break;
 597                        default:
 598                                helper_evaluate_flags(env);
 599                                break;
 600                }
 601                break;
 602                case CC_OP_FLAGS:
 603                        /* live.  */
 604                        break;
 605                case CC_OP_SUB:
 606                case CC_OP_CMP:
 607                        if (env->cc_size == 4)
 608                                env->pregs[PR_CCS] =
 609                                        helper_evaluate_flags_sub_4(env,
 610                                                env->pregs[PR_CCS],
 611                                                env->cc_src, env->cc_dest,
 612                                                env->cc_result);
 613                        else
 614                                helper_evaluate_flags(env);
 615                        break;
 616                default:
 617                {
 618                        switch (env->cc_size)
 619                        {
 620                        case 4:
 621                                env->pregs[PR_CCS] =
 622                                        helper_evaluate_flags_alu_4(env,
 623                                                env->pregs[PR_CCS],
 624                                                env->cc_src, env->cc_dest,
 625                                                env->cc_result);
 626                                break;
 627                        default:
 628                                helper_evaluate_flags(env);
 629                                break;
 630                        }
 631                }
 632                break;
 633        }
 634}
 635