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/cpu_ldst.h"
  27
  28//#define CRIS_OP_HELPER_DEBUG
  29
  30
  31#ifdef CRIS_OP_HELPER_DEBUG
  32#define D(x) x
  33#define D_LOG(...) qemu_log(__VA_ARGS__)
  34#else
  35#define D(x)
  36#define D_LOG(...) do { } while (0)
  37#endif
  38
  39#if !defined(CONFIG_USER_ONLY)
  40/* Try to fill the TLB and return an exception if error. If retaddr is
  41   NULL, it means that the function was called in C code (i.e. not
  42   from generated code or from helper.c) */
  43void tlb_fill(CPUState *cs, target_ulong addr, int is_write, int mmu_idx,
  44              uintptr_t retaddr)
  45{
  46    CRISCPU *cpu = CRIS_CPU(cs);
  47    CPUCRISState *env = &cpu->env;
  48    int ret;
  49
  50    D_LOG("%s pc=%x tpc=%x ra=%p\n", __func__,
  51          env->pc, env->pregs[PR_EDA], (void *)retaddr);
  52    ret = cris_cpu_handle_mmu_fault(cs, addr, is_write, mmu_idx);
  53    if (unlikely(ret)) {
  54        if (retaddr) {
  55            /* now we have a real cpu fault */
  56            if (cpu_restore_state(cs, retaddr)) {
  57                /* Evaluate flags after retranslation.  */
  58                helper_top_evaluate_flags(env);
  59            }
  60        }
  61        cpu_loop_exit(cs);
  62    }
  63}
  64
  65#endif
  66
  67void helper_raise_exception(CPUCRISState *env, uint32_t index)
  68{
  69    CPUState *cs = CPU(cris_env_get_cpu(env));
  70
  71    cs->exception_index = index;
  72    cpu_loop_exit(cs);
  73}
  74
  75void helper_tlb_flush_pid(CPUCRISState *env, uint32_t pid)
  76{
  77#if !defined(CONFIG_USER_ONLY)
  78        pid &= 0xff;
  79        if (pid != (env->pregs[PR_PID] & 0xff))
  80                cris_mmu_flush_pid(env, env->pregs[PR_PID]);
  81#endif
  82}
  83
  84void helper_spc_write(CPUCRISState *env, uint32_t new_spc)
  85{
  86#if !defined(CONFIG_USER_ONLY)
  87    CRISCPU *cpu = cris_env_get_cpu(env);
  88    CPUState *cs = CPU(cpu);
  89
  90    tlb_flush_page(cs, env->pregs[PR_SPC]);
  91    tlb_flush_page(cs, new_spc);
  92#endif
  93}
  94
  95/* Used by the tlb decoder.  */
  96#define EXTRACT_FIELD(src, start, end) \
  97            (((src) >> start) & ((1 << (end - start + 1)) - 1))
  98
  99void helper_movl_sreg_reg(CPUCRISState *env, uint32_t sreg, uint32_t reg)
 100{
 101#if !defined(CONFIG_USER_ONLY)
 102    CRISCPU *cpu = cris_env_get_cpu(env);
 103#endif
 104        uint32_t srs;
 105        srs = env->pregs[PR_SRS];
 106        srs &= 3;
 107        env->sregs[srs][sreg] = env->regs[reg];
 108
 109#if !defined(CONFIG_USER_ONLY)
 110        if (srs == 1 || srs == 2) {
 111                if (sreg == 6) {
 112                        /* Writes to tlb-hi write to mm_cause as a side 
 113                           effect.  */
 114                        env->sregs[SFR_RW_MM_TLB_HI] = env->regs[reg];
 115                        env->sregs[SFR_R_MM_CAUSE] = env->regs[reg];
 116                }
 117                else if (sreg == 5) {
 118                        uint32_t set;
 119                        uint32_t idx;
 120                        uint32_t lo, hi;
 121                        uint32_t vaddr;
 122                        int tlb_v;
 123
 124                        idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
 125                        set >>= 4;
 126                        set &= 3;
 127
 128                        idx &= 15;
 129                        /* We've just made a write to tlb_lo.  */
 130                        lo = env->sregs[SFR_RW_MM_TLB_LO];
 131                        /* Writes are done via r_mm_cause.  */
 132                        hi = env->sregs[SFR_R_MM_CAUSE];
 133
 134                        vaddr = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].hi,
 135                                              13, 31);
 136                        vaddr <<= TARGET_PAGE_BITS;
 137                        tlb_v = EXTRACT_FIELD(env->tlbsets[srs-1][set][idx].lo,
 138                                            3, 3);
 139                        env->tlbsets[srs - 1][set][idx].lo = lo;
 140                        env->tlbsets[srs - 1][set][idx].hi = hi;
 141
 142                        D_LOG("tlb flush vaddr=%x v=%d pc=%x\n", 
 143                                  vaddr, tlb_v, env->pc);
 144                        if (tlb_v) {
 145                tlb_flush_page(CPU(cpu), vaddr);
 146                        }
 147                }
 148        }
 149#endif
 150}
 151
 152void helper_movl_reg_sreg(CPUCRISState *env, uint32_t reg, uint32_t sreg)
 153{
 154        uint32_t srs;
 155        env->pregs[PR_SRS] &= 3;
 156        srs = env->pregs[PR_SRS];
 157        
 158#if !defined(CONFIG_USER_ONLY)
 159        if (srs == 1 || srs == 2)
 160        {
 161                uint32_t set;
 162                uint32_t idx;
 163                uint32_t lo, hi;
 164
 165                idx = set = env->sregs[SFR_RW_MM_TLB_SEL];
 166                set >>= 4;
 167                set &= 3;
 168                idx &= 15;
 169
 170                /* Update the mirror regs.  */
 171                hi = env->tlbsets[srs - 1][set][idx].hi;
 172                lo = env->tlbsets[srs - 1][set][idx].lo;
 173                env->sregs[SFR_RW_MM_TLB_HI] = hi;
 174                env->sregs[SFR_RW_MM_TLB_LO] = lo;
 175        }
 176#endif
 177        env->regs[reg] = env->sregs[srs][sreg];
 178}
 179
 180static void cris_ccs_rshift(CPUCRISState *env)
 181{
 182        uint32_t ccs;
 183
 184        /* Apply the ccs shift.  */
 185        ccs = env->pregs[PR_CCS];
 186        ccs = (ccs & 0xc0000000) | ((ccs & 0x0fffffff) >> 10);
 187        if (ccs & U_FLAG)
 188        {
 189                /* Enter user mode.  */
 190                env->ksp = env->regs[R_SP];
 191                env->regs[R_SP] = env->pregs[PR_USP];
 192        }
 193
 194        env->pregs[PR_CCS] = ccs;
 195}
 196
 197void helper_rfe(CPUCRISState *env)
 198{
 199        int rflag = env->pregs[PR_CCS] & R_FLAG;
 200
 201        D_LOG("rfe: erp=%x pid=%x ccs=%x btarget=%x\n", 
 202                 env->pregs[PR_ERP], env->pregs[PR_PID],
 203                 env->pregs[PR_CCS],
 204                 env->btarget);
 205
 206        cris_ccs_rshift(env);
 207
 208        /* RFE sets the P_FLAG only if the R_FLAG is not set.  */
 209        if (!rflag)
 210                env->pregs[PR_CCS] |= P_FLAG;
 211}
 212
 213void helper_rfn(CPUCRISState *env)
 214{
 215        int rflag = env->pregs[PR_CCS] & R_FLAG;
 216
 217        D_LOG("rfn: erp=%x pid=%x ccs=%x btarget=%x\n", 
 218                 env->pregs[PR_ERP], env->pregs[PR_PID],
 219                 env->pregs[PR_CCS],
 220                 env->btarget);
 221
 222        cris_ccs_rshift(env);
 223
 224        /* Set the P_FLAG only if the R_FLAG is not set.  */
 225        if (!rflag)
 226                env->pregs[PR_CCS] |= P_FLAG;
 227
 228        /* Always set the M flag.  */
 229        env->pregs[PR_CCS] |= M_FLAG_V32;
 230}
 231
 232uint32_t helper_lz(uint32_t t0)
 233{
 234        return clz32(t0);
 235}
 236
 237uint32_t helper_btst(CPUCRISState *env, uint32_t t0, uint32_t t1, uint32_t ccs)
 238{
 239        /* FIXME: clean this up.  */
 240
 241        /* des ref:
 242           The N flag is set according to the selected bit in the dest reg.
 243           The Z flag is set if the selected bit and all bits to the right are
 244           zero.
 245           The X flag is cleared.
 246           Other flags are left untouched.
 247           The destination reg is not affected.*/
 248        unsigned int fz, sbit, bset, mask, masked_t0;
 249
 250        sbit = t1 & 31;
 251        bset = !!(t0 & (1 << sbit));
 252        mask = sbit == 31 ? -1 : (1 << (sbit + 1)) - 1;
 253        masked_t0 = t0 & mask;
 254        fz = !(masked_t0 | bset);
 255
 256        /* Clear the X, N and Z flags.  */
 257        ccs = ccs & ~(X_FLAG | N_FLAG | Z_FLAG);
 258        if (env->pregs[PR_VR] < 32)
 259                ccs &= ~(V_FLAG | C_FLAG);
 260        /* Set the N and Z flags accordingly.  */
 261        ccs |= (bset << 3) | (fz << 2);
 262        return ccs;
 263}
 264
 265static inline uint32_t evaluate_flags_writeback(CPUCRISState *env,
 266                                                uint32_t flags, uint32_t ccs)
 267{
 268        unsigned int x, z, mask;
 269
 270        /* Extended arithmetics, leave the z flag alone.  */
 271        x = env->cc_x;
 272        mask = env->cc_mask | X_FLAG;
 273        if (x) {
 274                z = flags & Z_FLAG;
 275                mask = mask & ~z;
 276        }
 277        flags &= mask;
 278
 279        /* all insn clear the x-flag except setf or clrf.  */
 280        ccs &= ~mask;
 281        ccs |= flags;
 282        return ccs;
 283}
 284
 285uint32_t helper_evaluate_flags_muls(CPUCRISState *env,
 286                                    uint32_t ccs, uint32_t res, uint32_t mof)
 287{
 288        uint32_t flags = 0;
 289        int64_t tmp;
 290        int dneg;
 291
 292        dneg = ((int32_t)res) < 0;
 293
 294        tmp = mof;
 295        tmp <<= 32;
 296        tmp |= res;
 297        if (tmp == 0)
 298                flags |= Z_FLAG;
 299        else if (tmp < 0)
 300                flags |= N_FLAG;
 301        if ((dneg && mof != -1)
 302            || (!dneg && mof != 0))
 303                flags |= V_FLAG;
 304        return evaluate_flags_writeback(env, flags, ccs);
 305}
 306
 307uint32_t helper_evaluate_flags_mulu(CPUCRISState *env,
 308                                    uint32_t ccs, uint32_t res, uint32_t mof)
 309{
 310        uint32_t flags = 0;
 311        uint64_t tmp;
 312
 313        tmp = mof;
 314        tmp <<= 32;
 315        tmp |= res;
 316        if (tmp == 0)
 317                flags |= Z_FLAG;
 318        else if (tmp >> 63)
 319                flags |= N_FLAG;
 320        if (mof)
 321                flags |= V_FLAG;
 322
 323        return evaluate_flags_writeback(env, flags, ccs);
 324}
 325
 326uint32_t helper_evaluate_flags_mcp(CPUCRISState *env, uint32_t ccs,
 327                                   uint32_t src, uint32_t dst, uint32_t res)
 328{
 329        uint32_t flags = 0;
 330
 331        src = src & 0x80000000;
 332        dst = dst & 0x80000000;
 333
 334        if ((res & 0x80000000L) != 0L)
 335        {
 336                flags |= N_FLAG;
 337                if (!src && !dst)
 338                        flags |= V_FLAG;
 339                else if (src & dst)
 340                        flags |= R_FLAG;
 341        }
 342        else
 343        {
 344                if (res == 0L)
 345                        flags |= Z_FLAG;
 346                if (src & dst) 
 347                        flags |= V_FLAG;
 348                if (dst | src) 
 349                        flags |= R_FLAG;
 350        }
 351
 352        return evaluate_flags_writeback(env, flags, ccs);
 353}
 354
 355uint32_t helper_evaluate_flags_alu_4(CPUCRISState *env, uint32_t ccs,
 356                                     uint32_t src, uint32_t dst, uint32_t res)
 357{
 358        uint32_t flags = 0;
 359
 360        src = src & 0x80000000;
 361        dst = dst & 0x80000000;
 362
 363        if ((res & 0x80000000L) != 0L)
 364        {
 365                flags |= N_FLAG;
 366                if (!src && !dst)
 367                        flags |= V_FLAG;
 368                else if (src & dst)
 369                        flags |= C_FLAG;
 370        }
 371        else
 372        {
 373                if (res == 0L)
 374                        flags |= Z_FLAG;
 375                if (src & dst) 
 376                        flags |= V_FLAG;
 377                if (dst | src) 
 378                        flags |= C_FLAG;
 379        }
 380
 381        return evaluate_flags_writeback(env, flags, ccs);
 382}
 383
 384uint32_t helper_evaluate_flags_sub_4(CPUCRISState *env, uint32_t ccs,
 385                                     uint32_t src, uint32_t dst, uint32_t res)
 386{
 387        uint32_t flags = 0;
 388
 389        src = (~src) & 0x80000000;
 390        dst = dst & 0x80000000;
 391
 392        if ((res & 0x80000000L) != 0L)
 393        {
 394                flags |= N_FLAG;
 395                if (!src && !dst)
 396                        flags |= V_FLAG;
 397                else if (src & dst)
 398                        flags |= C_FLAG;
 399        }
 400        else
 401        {
 402                if (res == 0L)
 403                        flags |= Z_FLAG;
 404                if (src & dst) 
 405                        flags |= V_FLAG;
 406                if (dst | src) 
 407                        flags |= C_FLAG;
 408        }
 409
 410        flags ^= C_FLAG;
 411        return evaluate_flags_writeback(env, flags, ccs);
 412}
 413
 414uint32_t helper_evaluate_flags_move_4(CPUCRISState *env,
 415                                      uint32_t ccs, uint32_t res)
 416{
 417        uint32_t flags = 0;
 418
 419        if ((int32_t)res < 0)
 420                flags |= N_FLAG;
 421        else if (res == 0L)
 422                flags |= Z_FLAG;
 423
 424        return evaluate_flags_writeback(env, flags, ccs);
 425}
 426uint32_t helper_evaluate_flags_move_2(CPUCRISState *env,
 427                                      uint32_t ccs, uint32_t res)
 428{
 429        uint32_t flags = 0;
 430
 431        if ((int16_t)res < 0L)
 432                flags |= N_FLAG;
 433        else if (res == 0)
 434                flags |= Z_FLAG;
 435
 436        return evaluate_flags_writeback(env, flags, ccs);
 437}
 438
 439/* TODO: This is expensive. We could split things up and only evaluate part of
 440   CCR on a need to know basis. For now, we simply re-evaluate everything.  */
 441void helper_evaluate_flags(CPUCRISState *env)
 442{
 443        uint32_t src, dst, res;
 444        uint32_t flags = 0;
 445
 446        src = env->cc_src;
 447        dst = env->cc_dest;
 448        res = env->cc_result;
 449
 450        if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 451                src = ~src;
 452
 453        /* Now, evaluate the flags. This stuff is based on
 454           Per Zander's CRISv10 simulator.  */
 455        switch (env->cc_size)
 456        {
 457                case 1:
 458                        if ((res & 0x80L) != 0L)
 459                        {
 460                                flags |= N_FLAG;
 461                                if (((src & 0x80L) == 0L)
 462                                    && ((dst & 0x80L) == 0L))
 463                                {
 464                                        flags |= V_FLAG;
 465                                }
 466                                else if (((src & 0x80L) != 0L)
 467                                         && ((dst & 0x80L) != 0L))
 468                                {
 469                                        flags |= C_FLAG;
 470                                }
 471                        }
 472                        else
 473                        {
 474                                if ((res & 0xFFL) == 0L)
 475                                {
 476                                        flags |= Z_FLAG;
 477                                }
 478                                if (((src & 0x80L) != 0L)
 479                                    && ((dst & 0x80L) != 0L))
 480                                {
 481                                        flags |= V_FLAG;
 482                                }
 483                                if ((dst & 0x80L) != 0L
 484                                    || (src & 0x80L) != 0L)
 485                                {
 486                                        flags |= C_FLAG;
 487                                }
 488                        }
 489                        break;
 490                case 2:
 491                        if ((res & 0x8000L) != 0L)
 492                        {
 493                                flags |= N_FLAG;
 494                                if (((src & 0x8000L) == 0L)
 495                                    && ((dst & 0x8000L) == 0L))
 496                                {
 497                                        flags |= V_FLAG;
 498                                }
 499                                else if (((src & 0x8000L) != 0L)
 500                                         && ((dst & 0x8000L) != 0L))
 501                                {
 502                                        flags |= C_FLAG;
 503                                }
 504                        }
 505                        else
 506                        {
 507                                if ((res & 0xFFFFL) == 0L)
 508                                {
 509                                        flags |= Z_FLAG;
 510                                }
 511                                if (((src & 0x8000L) != 0L)
 512                                    && ((dst & 0x8000L) != 0L))
 513                                {
 514                                        flags |= V_FLAG;
 515                                }
 516                                if ((dst & 0x8000L) != 0L
 517                                    || (src & 0x8000L) != 0L)
 518                                {
 519                                        flags |= C_FLAG;
 520                                }
 521                        }
 522                        break;
 523                case 4:
 524                        if ((res & 0x80000000L) != 0L)
 525                        {
 526                                flags |= N_FLAG;
 527                                if (((src & 0x80000000L) == 0L)
 528                                    && ((dst & 0x80000000L) == 0L))
 529                                {
 530                                        flags |= V_FLAG;
 531                                }
 532                                else if (((src & 0x80000000L) != 0L) &&
 533                                         ((dst & 0x80000000L) != 0L))
 534                                {
 535                                        flags |= C_FLAG;
 536                                }
 537                        }
 538                        else
 539                        {
 540                                if (res == 0L)
 541                                        flags |= Z_FLAG;
 542                                if (((src & 0x80000000L) != 0L)
 543                                    && ((dst & 0x80000000L) != 0L))
 544                                        flags |= V_FLAG;
 545                                if ((dst & 0x80000000L) != 0L
 546                                    || (src & 0x80000000L) != 0L)
 547                                        flags |= C_FLAG;
 548                        }
 549                        break;
 550                default:
 551                        break;
 552        }
 553
 554        if (env->cc_op == CC_OP_SUB || env->cc_op == CC_OP_CMP)
 555                flags ^= C_FLAG;
 556
 557        env->pregs[PR_CCS] = evaluate_flags_writeback(env, flags,
 558                                                      env->pregs[PR_CCS]);
 559}
 560
 561void helper_top_evaluate_flags(CPUCRISState *env)
 562{
 563        switch (env->cc_op)
 564        {
 565                case CC_OP_MCP:
 566                        env->pregs[PR_CCS] = helper_evaluate_flags_mcp(env,
 567                                        env->pregs[PR_CCS], env->cc_src,
 568                                        env->cc_dest, env->cc_result);
 569                        break;
 570                case CC_OP_MULS:
 571                        env->pregs[PR_CCS] = helper_evaluate_flags_muls(env,
 572                                        env->pregs[PR_CCS], env->cc_result,
 573                                        env->pregs[PR_MOF]);
 574                        break;
 575                case CC_OP_MULU:
 576                        env->pregs[PR_CCS] = helper_evaluate_flags_mulu(env,
 577                                        env->pregs[PR_CCS], env->cc_result,
 578                                        env->pregs[PR_MOF]);
 579                        break;
 580                case CC_OP_MOVE:
 581                case CC_OP_AND:
 582                case CC_OP_OR:
 583                case CC_OP_XOR:
 584                case CC_OP_ASR:
 585                case CC_OP_LSR:
 586                case CC_OP_LSL:
 587                switch (env->cc_size)
 588                {
 589                        case 4:
 590                                env->pregs[PR_CCS] =
 591                                        helper_evaluate_flags_move_4(env,
 592                                                        env->pregs[PR_CCS],
 593                                                        env->cc_result);
 594                                break;
 595                        case 2:
 596                                env->pregs[PR_CCS] =
 597                                        helper_evaluate_flags_move_2(env,
 598                                                        env->pregs[PR_CCS],
 599                                                        env->cc_result);
 600                                break;
 601                        default:
 602                                helper_evaluate_flags(env);
 603                                break;
 604                }
 605                break;
 606                case CC_OP_FLAGS:
 607                        /* live.  */
 608                        break;
 609                case CC_OP_SUB:
 610                case CC_OP_CMP:
 611                        if (env->cc_size == 4)
 612                                env->pregs[PR_CCS] =
 613                                        helper_evaluate_flags_sub_4(env,
 614                                                env->pregs[PR_CCS],
 615                                                env->cc_src, env->cc_dest,
 616                                                env->cc_result);
 617                        else
 618                                helper_evaluate_flags(env);
 619                        break;
 620                default:
 621                {
 622                        switch (env->cc_size)
 623                        {
 624                        case 4:
 625                                env->pregs[PR_CCS] =
 626                                        helper_evaluate_flags_alu_4(env,
 627                                                env->pregs[PR_CCS],
 628                                                env->cc_src, env->cc_dest,
 629                                                env->cc_result);
 630                                break;
 631                        default:
 632                                helper_evaluate_flags(env);
 633                                break;
 634                        }
 635                }
 636                break;
 637        }
 638}
 639