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