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, MMUAccessType access_type,
  45              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, 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)) {
  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_lz(uint32_t t0)
 234{
 235        return clz32(t0);
 236}
 237
 238uint32_t helper_btst(CPUCRISState *env, uint32_t t0, uint32_t t1, uint32_t ccs)
 239{
 240        /* FIXME: clean this up.  */
 241
 242        /* des ref:
 243           The N flag is set according to the selected bit in the dest reg.
 244           The Z flag is set if the selected bit and all bits to the right are
 245           zero.
 246           The X flag is cleared.
 247           Other flags are left untouched.
 248           The destination reg is not affected.*/
 249        unsigned int fz, sbit, bset, mask, masked_t0;
 250
 251        sbit = t1 & 31;
 252        bset = !!(t0 & (1 << sbit));
 253        mask = sbit == 31 ? -1 : (1 << (sbit + 1)) - 1;
 254        masked_t0 = t0 & mask;
 255        fz = !(masked_t0 | bset);
 256
 257        /* Clear the X, N and Z flags.  */
 258        ccs = ccs & ~(X_FLAG | N_FLAG | Z_FLAG);
 259        if (env->pregs[PR_VR] < 32)
 260                ccs &= ~(V_FLAG | C_FLAG);
 261        /* Set the N and Z flags accordingly.  */
 262        ccs |= (bset << 3) | (fz << 2);
 263        return ccs;
 264}
 265
 266static inline uint32_t evaluate_flags_writeback(CPUCRISState *env,
 267                                                uint32_t flags, uint32_t ccs)
 268{
 269        unsigned int x, z, mask;
 270
 271        /* Extended arithmetics, leave the z flag alone.  */
 272        x = env->cc_x;
 273        mask = env->cc_mask | X_FLAG;
 274        if (x) {
 275                z = flags & Z_FLAG;
 276                mask = mask & ~z;
 277        }
 278        flags &= mask;
 279
 280        /* all insn clear the x-flag except setf or clrf.  */
 281        ccs &= ~mask;
 282        ccs |= flags;
 283        return ccs;
 284}
 285
 286uint32_t helper_evaluate_flags_muls(CPUCRISState *env,
 287                                    uint32_t ccs, uint32_t res, uint32_t mof)
 288{
 289        uint32_t flags = 0;
 290        int64_t tmp;
 291        int dneg;
 292
 293        dneg = ((int32_t)res) < 0;
 294
 295        tmp = mof;
 296        tmp <<= 32;
 297        tmp |= res;
 298        if (tmp == 0)
 299                flags |= Z_FLAG;
 300        else if (tmp < 0)
 301                flags |= N_FLAG;
 302        if ((dneg && mof != -1)
 303            || (!dneg && mof != 0))
 304                flags |= V_FLAG;
 305        return evaluate_flags_writeback(env, flags, ccs);
 306}
 307
 308uint32_t helper_evaluate_flags_mulu(CPUCRISState *env,
 309                                    uint32_t ccs, uint32_t res, uint32_t mof)
 310{
 311        uint32_t flags = 0;
 312        uint64_t tmp;
 313
 314        tmp = mof;
 315        tmp <<= 32;
 316        tmp |= res;
 317        if (tmp == 0)
 318                flags |= Z_FLAG;
 319        else if (tmp >> 63)
 320                flags |= N_FLAG;
 321        if (mof)
 322                flags |= V_FLAG;
 323
 324        return evaluate_flags_writeback(env, flags, ccs);
 325}
 326
 327uint32_t helper_evaluate_flags_mcp(CPUCRISState *env, uint32_t ccs,
 328                                   uint32_t src, uint32_t dst, uint32_t res)
 329{
 330        uint32_t flags = 0;
 331
 332        src = src & 0x80000000;
 333        dst = dst & 0x80000000;
 334
 335        if ((res & 0x80000000L) != 0L)
 336        {
 337                flags |= N_FLAG;
 338                if (!src && !dst)
 339                        flags |= V_FLAG;
 340                else if (src & dst)
 341                        flags |= R_FLAG;
 342        }
 343        else
 344        {
 345                if (res == 0L)
 346                        flags |= Z_FLAG;
 347                if (src & dst) 
 348                        flags |= V_FLAG;
 349                if (dst | src) 
 350                        flags |= R_FLAG;
 351        }
 352
 353        return evaluate_flags_writeback(env, flags, ccs);
 354}
 355
 356uint32_t helper_evaluate_flags_alu_4(CPUCRISState *env, uint32_t ccs,
 357                                     uint32_t src, uint32_t dst, uint32_t res)
 358{
 359        uint32_t flags = 0;
 360
 361        src = src & 0x80000000;
 362        dst = dst & 0x80000000;
 363
 364        if ((res & 0x80000000L) != 0L)
 365        {
 366                flags |= N_FLAG;
 367                if (!src && !dst)
 368                        flags |= V_FLAG;
 369                else if (src & dst)
 370                        flags |= C_FLAG;
 371        }
 372        else
 373        {
 374                if (res == 0L)
 375                        flags |= Z_FLAG;
 376                if (src & dst) 
 377                        flags |= V_FLAG;
 378                if (dst | src) 
 379                        flags |= C_FLAG;
 380        }
 381
 382        return evaluate_flags_writeback(env, flags, ccs);
 383}
 384
 385uint32_t helper_evaluate_flags_sub_4(CPUCRISState *env, uint32_t ccs,
 386                                     uint32_t src, uint32_t dst, uint32_t res)
 387{
 388        uint32_t flags = 0;
 389
 390        src = (~src) & 0x80000000;
 391        dst = dst & 0x80000000;
 392
 393        if ((res & 0x80000000L) != 0L)
 394        {
 395                flags |= N_FLAG;
 396                if (!src && !dst)
 397                        flags |= V_FLAG;
 398                else if (src & dst)
 399                        flags |= C_FLAG;
 400        }
 401        else
 402        {
 403                if (res == 0L)
 404                        flags |= Z_FLAG;
 405                if (src & dst) 
 406                        flags |= V_FLAG;
 407                if (dst | src) 
 408                        flags |= C_FLAG;
 409        }
 410
 411        flags ^= C_FLAG;
 412        return evaluate_flags_writeback(env, flags, ccs);
 413}
 414
 415uint32_t helper_evaluate_flags_move_4(CPUCRISState *env,
 416                                      uint32_t ccs, uint32_t res)
 417{
 418        uint32_t flags = 0;
 419
 420        if ((int32_t)res < 0)
 421                flags |= N_FLAG;
 422        else if (res == 0L)
 423                flags |= Z_FLAG;
 424
 425        return evaluate_flags_writeback(env, flags, ccs);
 426}
 427uint32_t helper_evaluate_flags_move_2(CPUCRISState *env,
 428                                      uint32_t ccs, uint32_t res)
 429{
 430        uint32_t flags = 0;
 431
 432        if ((int16_t)res < 0L)
 433                flags |= N_FLAG;
 434        else if (res == 0)
 435                flags |= Z_FLAG;
 436
 437        return evaluate_flags_writeback(env, flags, ccs);
 438}
 439
 440/* TODO: This is expensive. We could split things up and only evaluate part of
 441   CCR on a need to know basis. For now, we simply re-evaluate everything.  */
 442void helper_evaluate_flags(CPUCRISState *env)
 443{
 444        uint32_t src, dst, res;
 445        uint32_t flags = 0;
 446
 447        src = env->cc_src;
 448        dst = env->cc_dest;
 449        res = env->cc_result;
 450
 451        if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 452                src = ~src;
 453
 454        /* Now, evaluate the flags. This stuff is based on
 455           Per Zander's CRISv10 simulator.  */
 456        switch (env->cc_size)
 457        {
 458                case 1:
 459                        if ((res & 0x80L) != 0L)
 460                        {
 461                                flags |= N_FLAG;
 462                                if (((src & 0x80L) == 0L)
 463                                    && ((dst & 0x80L) == 0L))
 464                                {
 465                                        flags |= V_FLAG;
 466                                }
 467                                else if (((src & 0x80L) != 0L)
 468                                         && ((dst & 0x80L) != 0L))
 469                                {
 470                                        flags |= C_FLAG;
 471                                }
 472                        }
 473                        else
 474                        {
 475                                if ((res & 0xFFL) == 0L)
 476                                {
 477                                        flags |= Z_FLAG;
 478                                }
 479                                if (((src & 0x80L) != 0L)
 480                                    && ((dst & 0x80L) != 0L))
 481                                {
 482                                        flags |= V_FLAG;
 483                                }
 484                                if ((dst & 0x80L) != 0L
 485                                    || (src & 0x80L) != 0L)
 486                                {
 487                                        flags |= C_FLAG;
 488                                }
 489                        }
 490                        break;
 491                case 2:
 492                        if ((res & 0x8000L) != 0L)
 493                        {
 494                                flags |= N_FLAG;
 495                                if (((src & 0x8000L) == 0L)
 496                                    && ((dst & 0x8000L) == 0L))
 497                                {
 498                                        flags |= V_FLAG;
 499                                }
 500                                else if (((src & 0x8000L) != 0L)
 501                                         && ((dst & 0x8000L) != 0L))
 502                                {
 503                                        flags |= C_FLAG;
 504                                }
 505                        }
 506                        else
 507                        {
 508                                if ((res & 0xFFFFL) == 0L)
 509                                {
 510                                        flags |= Z_FLAG;
 511                                }
 512                                if (((src & 0x8000L) != 0L)
 513                                    && ((dst & 0x8000L) != 0L))
 514                                {
 515                                        flags |= V_FLAG;
 516                                }
 517                                if ((dst & 0x8000L) != 0L
 518                                    || (src & 0x8000L) != 0L)
 519                                {
 520                                        flags |= C_FLAG;
 521                                }
 522                        }
 523                        break;
 524                case 4:
 525                        if ((res & 0x80000000L) != 0L)
 526                        {
 527                                flags |= N_FLAG;
 528                                if (((src & 0x80000000L) == 0L)
 529                                    && ((dst & 0x80000000L) == 0L))
 530                                {
 531                                        flags |= V_FLAG;
 532                                }
 533                                else if (((src & 0x80000000L) != 0L) &&
 534                                         ((dst & 0x80000000L) != 0L))
 535                                {
 536                                        flags |= C_FLAG;
 537                                }
 538                        }
 539                        else
 540                        {
 541                                if (res == 0L)
 542                                        flags |= Z_FLAG;
 543                                if (((src & 0x80000000L) != 0L)
 544                                    && ((dst & 0x80000000L) != 0L))
 545                                        flags |= V_FLAG;
 546                                if ((dst & 0x80000000L) != 0L
 547                                    || (src & 0x80000000L) != 0L)
 548                                        flags |= C_FLAG;
 549                        }
 550                        break;
 551                default:
 552                        break;
 553        }
 554
 555        if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 556                flags ^= C_FLAG;
 557
 558        env->pregs[PR_CCS] = evaluate_flags_writeback(env, flags,
 559                                                      env->pregs[PR_CCS]);
 560}
 561
 562void helper_top_evaluate_flags(CPUCRISState *env)
 563{
 564        switch (env->cc_op)
 565        {
 566                case CC_OP_MCP:
 567                        env->pregs[PR_CCS] = helper_evaluate_flags_mcp(env,
 568                                        env->pregs[PR_CCS], env->cc_src,
 569                                        env->cc_dest, env->cc_result);
 570                        break;
 571                case CC_OP_MULS:
 572                        env->pregs[PR_CCS] = helper_evaluate_flags_muls(env,
 573                                        env->pregs[PR_CCS], env->cc_result,
 574                                        env->pregs[PR_MOF]);
 575                        break;
 576                case CC_OP_MULU:
 577                        env->pregs[PR_CCS] = helper_evaluate_flags_mulu(env,
 578                                        env->pregs[PR_CCS], env->cc_result,
 579                                        env->pregs[PR_MOF]);
 580                        break;
 581                case CC_OP_MOVE:
 582                case CC_OP_AND:
 583                case CC_OP_OR:
 584                case CC_OP_XOR:
 585                case CC_OP_ASR:
 586                case CC_OP_LSR:
 587                case CC_OP_LSL:
 588                switch (env->cc_size)
 589                {
 590                        case 4:
 591                                env->pregs[PR_CCS] =
 592                                        helper_evaluate_flags_move_4(env,
 593                                                        env->pregs[PR_CCS],
 594                                                        env->cc_result);
 595                                break;
 596                        case 2:
 597                                env->pregs[PR_CCS] =
 598                                        helper_evaluate_flags_move_2(env,
 599                                                        env->pregs[PR_CCS],
 600                                                        env->cc_result);
 601                                break;
 602                        default:
 603                                helper_evaluate_flags(env);
 604                                break;
 605                }
 606                break;
 607                case CC_OP_FLAGS:
 608                        /* live.  */
 609                        break;
 610                case CC_OP_SUB:
 611                case CC_OP_CMP:
 612                        if (env->cc_size == 4)
 613                                env->pregs[PR_CCS] =
 614                                        helper_evaluate_flags_sub_4(env,
 615                                                env->pregs[PR_CCS],
 616                                                env->cc_src, env->cc_dest,
 617                                                env->cc_result);
 618                        else
 619                                helper_evaluate_flags(env);
 620                        break;
 621                default:
 622                {
 623                        switch (env->cc_size)
 624                        {
 625                        case 4:
 626                                env->pregs[PR_CCS] =
 627                                        helper_evaluate_flags_alu_4(env,
 628                                                env->pregs[PR_CCS],
 629                                                env->cc_src, env->cc_dest,
 630                                                env->cc_result);
 631                                break;
 632                        default:
 633                                helper_evaluate_flags(env);
 634                                break;
 635                        }
 636                }
 637                break;
 638        }
 639}
 640