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inline unsigned long immu_simulate_tlb(unsigned long virtaddr)

{

  int set, way = -1;

  int i;

  unsigned long tagaddr;

  unsigned long vpn;

  if (!(mfspr(SPR_SR) & SPR_SR_IME) || !(testsprbits(SPR_UPR, SPR_UPR_IMP)))

    return virtaddr;

  /* Which set to check out? */

  set = (virtaddr / config.immu.pagesize) % config.immu.nsets;

  tagaddr = (virtaddr / config.immu.pagesize) / config.immu.nsets;

  vpn = virtaddr / config.immu.pagesize;

  /* Scan all ways and try to find a matching way. */

  for (i = 0; i < config.immu.nways; i++)

    if ((getsprbits(SPR_ITLBMR_BASE(i) + set, SPR_ITLBMR_VPN) == vpn) &&

        testsprbits(SPR_ITLBMR_BASE(i) + set, SPR_ITLBMR_V))

      way = i;

  /* Did we find our tlb entry? */

  if (way >= 0) { /* Yes, we did. */

    immu_stats.fetch_tlbhit++;

    debug(5, "ITLB hit (virtaddr=%x).\n", virtaddr);

    /* Test for page fault */

    if (mfspr (SPR_SR) & SPR_SR_SUPV) {

      if (!(mfspr (SPR_ITLBTR_BASE(way) + set) & SPR_ITLBTR_SWE))

        except_handle(EXCEPT_IPF, virtaddr);

    } else {

      if (!(mfspr (SPR_ITLBTR_BASE(way) + set) & SPR_ITLBTR_UWE))

        except_handle(EXCEPT_IPF, virtaddr);

    }

    /* Set LRUs */

    for (i = 0; i < config.immu.nways; i++)

      if (testsprbits(SPR_ITLBMR_BASE(i) + set, SPR_ITLBMR_LRU))

        setsprbits(SPR_ITLBMR_BASE(i) + set, SPR_ITLBMR_LRU, getsprbits(SPR_ITLBMR_BASE(i) + set, SPR_ITLBMR_LRU) - 1);

    setsprbits(SPR_ITLBMR_BASE(way) + set, SPR_ITLBMR_LRU, config.immu.ustates - 1);

    return getsprbits(SPR_ITLBTR_BASE(way) + set, SPR_ITLBTR_PPN) * config.immu.pagesize + (virtaddr % config.immu.pagesize);

  }

  else {  /* No, we didn't. */

    int minlru = config.immu.ustates - 1;

    int minway = 0;

    immu_stats.fetch_tlbmiss++;

#if 0

    for (i = 0; i < config.immu.nways; i++)

      if (getsprbits(SPR_ITLBMR_BASE(i) + set, SPR_ITLBMR_LRU) < minlru)

        minway = i;

    setsprbits(SPR_ITLBMR_BASE(minway) + set, SPR_ITLBMR_VPN, vpn);

    for (i = 0; i < config.immu.nways; i++)

      if (testsprbits(SPR_ITLBMR_BASE(i) + set, SPR_ITLBMR_LRU))

        setsprbits(SPR_ITLBMR_BASE(i) + set, SPR_ITLBMR_LRU, getsprbits(SPR_ITLBMR_BASE(i) + set, SPR_ITLBMR_LRU) - 1);

    setsprbits(SPR_ITLBMR_BASE(minway) + set, SPR_ITLBMR_LRU, config.immu.ustates - 1);

    setsprbits(SPR_ITLBTR_BASE(minway) + set, SPR_ITLBTR_PPN, vpn); /* 1 to 1 */

    setsprbits(SPR_ITLBMR_BASE(minway) + set, SPR_ITLBMR_V, 1);

#endif

    except_handle(EXCEPT_ITLBMISS, virtaddr);

    /* if tlb refill implemented in HW */

    /* return getsprbits(SPR_ITLBTR_BASE(minway) + set, SPR_ITLBTR_PPN) * config.immu.pagesize + (virtaddr % config.immu.pagesize); */

    return 0;

  }

}