arm: Clean up and document decoder API
[gem5.git] / src / arch / x86 / tlb.cc
index 4c8d96f8b1dae6ab1f0564c567b6f713dc4b0f1f..dd0aed77092b37bf521256e4f5608a6ae7db9a43 100644 (file)
  */
 
 #include <cstring>
+#include <memory>
 
-#include "config/full_system.hh"
-
-#include "arch/x86/faults.hh"
+#include "arch/generic/mmapped_ipr.hh"
 #include "arch/x86/insts/microldstop.hh"
-#include "arch/x86/pagetable.hh"
 #include "arch/x86/regs/misc.hh"
+#include "arch/x86/regs/msr.hh"
+#include "arch/x86/faults.hh"
+#include "arch/x86/pagetable.hh"
+#include "arch/x86/pagetable_walker.hh"
 #include "arch/x86/tlb.hh"
 #include "arch/x86/x86_traits.hh"
 #include "base/bitfield.hh"
 #include "base/trace.hh"
-#include "config/full_system.hh"
-#include "cpu/thread_context.hh"
 #include "cpu/base.hh"
+#include "cpu/thread_context.hh"
+#include "debug/TLB.hh"
 #include "mem/packet_access.hh"
-#include "mem/request.hh"
-
-#if FULL_SYSTEM
-#include "arch/x86/pagetable_walker.hh"
-#else
 #include "mem/page_table.hh"
+#include "mem/request.hh"
+#include "sim/full_system.hh"
 #include "sim/process.hh"
-#endif
 
 namespace X86ISA {
 
-TLB::TLB(const Params *p) : BaseTLB(p), configAddress(0), size(p->size)
+TLB::TLB(const Params *p) : BaseTLB(p), configAddress(0), size(p->size),
+    lruSeq(0)
 {
+    if (!size)
+        fatal("TLBs must have a non-zero size.\n");
     tlb = new TlbEntry[size];
     std::memset(tlb, 0, sizeof(TlbEntry) * size);
 
-    for (int x = 0; x < size; x++)
+    for (int x = 0; x < size; x++) {
+        tlb[x].trieHandle = NULL;
         freeList.push_back(&tlb[x]);
+    }
 
-#if FULL_SYSTEM
     walker = p->walker;
     walker->setTLB(this);
-#endif
 }
 
-TlbEntry *
-TLB::insert(Addr vpn, TlbEntry &entry)
+void
+TLB::evictLRU()
 {
-    //TODO Deal with conflicting entries
+    // Find the entry with the lowest (and hence least recently updated)
+    // sequence number.
 
-    TlbEntry *newEntry = NULL;
-    if (!freeList.empty()) {
-        newEntry = freeList.front();
-        freeList.pop_front();
-    } else {
-        newEntry = entryList.back();
-        entryList.pop_back();
+    unsigned lru = 0;
+    for (unsigned i = 1; i < size; i++) {
+        if (tlb[i].lruSeq < tlb[lru].lruSeq)
+            lru = i;
     }
-    *newEntry = entry;
-    newEntry->vaddr = vpn;
-    entryList.push_front(newEntry);
-    return newEntry;
+
+    assert(tlb[lru].trieHandle);
+    trie.remove(tlb[lru].trieHandle);
+    tlb[lru].trieHandle = NULL;
+    freeList.push_back(&tlb[lru]);
 }
 
-TLB::EntryList::iterator
-TLB::lookupIt(Addr va, bool update_lru)
+TlbEntry *
+TLB::insert(Addr vpn, TlbEntry &entry)
 {
-    //TODO make this smarter at some point
-    EntryList::iterator entry;
-    for (entry = entryList.begin(); entry != entryList.end(); entry++) {
-        if ((*entry)->vaddr <= va && (*entry)->vaddr + (*entry)->size > va) {
-            DPRINTF(TLB, "Matched vaddr %#x to entry starting at %#x "
-                    "with size %#x.\n", va, (*entry)->vaddr, (*entry)->size);
-            if (update_lru) {
-                entryList.push_front(*entry);
-                entryList.erase(entry);
-                entry = entryList.begin();
-            }
-            break;
-        }
+    // If somebody beat us to it, just use that existing entry.
+    TlbEntry *newEntry = trie.lookup(vpn);
+    if (newEntry) {
+        assert(newEntry->vaddr == vpn);
+        return newEntry;
     }
-    return entry;
+
+    if (freeList.empty())
+        evictLRU();
+
+    newEntry = freeList.front();
+    freeList.pop_front();
+
+    *newEntry = entry;
+    newEntry->lruSeq = nextSeq();
+    newEntry->vaddr = vpn;
+    newEntry->trieHandle =
+    trie.insert(vpn, TlbEntryTrie::MaxBits - entry.logBytes, newEntry);
+    return newEntry;
 }
 
 TlbEntry *
 TLB::lookup(Addr va, bool update_lru)
 {
-    EntryList::iterator entry = lookupIt(va, update_lru);
-    if (entry == entryList.end())
-        return NULL;
-    else
-        return *entry;
+    TlbEntry *entry = trie.lookup(va);
+    if (entry && update_lru)
+        entry->lruSeq = nextSeq();
+    return entry;
 }
 
 void
-TLB::invalidateAll()
+TLB::flushAll()
 {
     DPRINTF(TLB, "Invalidating all entries.\n");
-    while (!entryList.empty()) {
-        TlbEntry *entry = entryList.front();
-        entryList.pop_front();
-        freeList.push_back(entry);
+    for (unsigned i = 0; i < size; i++) {
+        if (tlb[i].trieHandle) {
+            trie.remove(tlb[i].trieHandle);
+            tlb[i].trieHandle = NULL;
+            freeList.push_back(&tlb[i]);
+        }
     }
 }
 
@@ -145,16 +150,14 @@ TLB::setConfigAddress(uint32_t addr)
 }
 
 void
-TLB::invalidateNonGlobal()
+TLB::flushNonGlobal()
 {
     DPRINTF(TLB, "Invalidating all non global entries.\n");
-    EntryList::iterator entryIt;
-    for (entryIt = entryList.begin(); entryIt != entryList.end();) {
-        if (!(*entryIt)->global) {
-            freeList.push_back(*entryIt);
-            entryList.erase(entryIt++);
-        } else {
-            entryIt++;
+    for (unsigned i = 0; i < size; i++) {
+        if (tlb[i].trieHandle && !tlb[i].global) {
+            trie.remove(tlb[i].trieHandle);
+            tlb[i].trieHandle = NULL;
+            freeList.push_back(&tlb[i]);
         }
     }
 }
@@ -162,10 +165,11 @@ TLB::invalidateNonGlobal()
 void
 TLB::demapPage(Addr va, uint64_t asn)
 {
-    EntryList::iterator entry = lookupIt(va, false);
-    if (entry != entryList.end()) {
-        freeList.push_back(*entry);
-        entryList.erase(entry);
+    TlbEntry *entry = trie.lookup(va);
+    if (entry) {
+        trie.remove(entry->trieHandle);
+        entry->trieHandle = NULL;
+        freeList.push_back(entry);
     }
 }
 
@@ -178,326 +182,17 @@ TLB::translateInt(RequestPtr req, ThreadContext *tc)
     if (prefix == IntAddrPrefixCPUID) {
         panic("CPUID memory space not yet implemented!\n");
     } else if (prefix == IntAddrPrefixMSR) {
-        vaddr = vaddr >> 3;
-        req->setFlags(Request::MMAPED_IPR);
-        Addr regNum = 0;
-        switch (vaddr & ~IntAddrPrefixMask) {
-          case 0x10:
-            regNum = MISCREG_TSC;
-            break;
-          case 0x1B:
-            regNum = MISCREG_APIC_BASE;
-            break;
-          case 0xFE:
-            regNum = MISCREG_MTRRCAP;
-            break;
-          case 0x174:
-            regNum = MISCREG_SYSENTER_CS;
-            break;
-          case 0x175:
-            regNum = MISCREG_SYSENTER_ESP;
-            break;
-          case 0x176:
-            regNum = MISCREG_SYSENTER_EIP;
-            break;
-          case 0x179:
-            regNum = MISCREG_MCG_CAP;
-            break;
-          case 0x17A:
-            regNum = MISCREG_MCG_STATUS;
-            break;
-          case 0x17B:
-            regNum = MISCREG_MCG_CTL;
-            break;
-          case 0x1D9:
-            regNum = MISCREG_DEBUG_CTL_MSR;
-            break;
-          case 0x1DB:
-            regNum = MISCREG_LAST_BRANCH_FROM_IP;
-            break;
-          case 0x1DC:
-            regNum = MISCREG_LAST_BRANCH_TO_IP;
-            break;
-          case 0x1DD:
-            regNum = MISCREG_LAST_EXCEPTION_FROM_IP;
-            break;
-          case 0x1DE:
-            regNum = MISCREG_LAST_EXCEPTION_TO_IP;
-            break;
-          case 0x200:
-            regNum = MISCREG_MTRR_PHYS_BASE_0;
-            break;
-          case 0x201:
-            regNum = MISCREG_MTRR_PHYS_MASK_0;
-            break;
-          case 0x202:
-            regNum = MISCREG_MTRR_PHYS_BASE_1;
-            break;
-          case 0x203:
-            regNum = MISCREG_MTRR_PHYS_MASK_1;
-            break;
-          case 0x204:
-            regNum = MISCREG_MTRR_PHYS_BASE_2;
-            break;
-          case 0x205:
-            regNum = MISCREG_MTRR_PHYS_MASK_2;
-            break;
-          case 0x206:
-            regNum = MISCREG_MTRR_PHYS_BASE_3;
-            break;
-          case 0x207:
-            regNum = MISCREG_MTRR_PHYS_MASK_3;
-            break;
-          case 0x208:
-            regNum = MISCREG_MTRR_PHYS_BASE_4;
-            break;
-          case 0x209:
-            regNum = MISCREG_MTRR_PHYS_MASK_4;
-            break;
-          case 0x20A:
-            regNum = MISCREG_MTRR_PHYS_BASE_5;
-            break;
-          case 0x20B:
-            regNum = MISCREG_MTRR_PHYS_MASK_5;
-            break;
-          case 0x20C:
-            regNum = MISCREG_MTRR_PHYS_BASE_6;
-            break;
-          case 0x20D:
-            regNum = MISCREG_MTRR_PHYS_MASK_6;
-            break;
-          case 0x20E:
-            regNum = MISCREG_MTRR_PHYS_BASE_7;
-            break;
-          case 0x20F:
-            regNum = MISCREG_MTRR_PHYS_MASK_7;
-            break;
-          case 0x250:
-            regNum = MISCREG_MTRR_FIX_64K_00000;
-            break;
-          case 0x258:
-            regNum = MISCREG_MTRR_FIX_16K_80000;
-            break;
-          case 0x259:
-            regNum = MISCREG_MTRR_FIX_16K_A0000;
-            break;
-          case 0x268:
-            regNum = MISCREG_MTRR_FIX_4K_C0000;
-            break;
-          case 0x269:
-            regNum = MISCREG_MTRR_FIX_4K_C8000;
-            break;
-          case 0x26A:
-            regNum = MISCREG_MTRR_FIX_4K_D0000;
-            break;
-          case 0x26B:
-            regNum = MISCREG_MTRR_FIX_4K_D8000;
-            break;
-          case 0x26C:
-            regNum = MISCREG_MTRR_FIX_4K_E0000;
-            break;
-          case 0x26D:
-            regNum = MISCREG_MTRR_FIX_4K_E8000;
-            break;
-          case 0x26E:
-            regNum = MISCREG_MTRR_FIX_4K_F0000;
-            break;
-          case 0x26F:
-            regNum = MISCREG_MTRR_FIX_4K_F8000;
-            break;
-          case 0x277:
-            regNum = MISCREG_PAT;
-            break;
-          case 0x2FF:
-            regNum = MISCREG_DEF_TYPE;
-            break;
-          case 0x400:
-            regNum = MISCREG_MC0_CTL;
-            break;
-          case 0x404:
-            regNum = MISCREG_MC1_CTL;
-            break;
-          case 0x408:
-            regNum = MISCREG_MC2_CTL;
-            break;
-          case 0x40C:
-            regNum = MISCREG_MC3_CTL;
-            break;
-          case 0x410:
-            regNum = MISCREG_MC4_CTL;
-            break;
-          case 0x414:
-            regNum = MISCREG_MC5_CTL;
-            break;
-          case 0x418:
-            regNum = MISCREG_MC6_CTL;
-            break;
-          case 0x41C:
-            regNum = MISCREG_MC7_CTL;
-            break;
-          case 0x401:
-            regNum = MISCREG_MC0_STATUS;
-            break;
-          case 0x405:
-            regNum = MISCREG_MC1_STATUS;
-            break;
-          case 0x409:
-            regNum = MISCREG_MC2_STATUS;
-            break;
-          case 0x40D:
-            regNum = MISCREG_MC3_STATUS;
-            break;
-          case 0x411:
-            regNum = MISCREG_MC4_STATUS;
-            break;
-          case 0x415:
-            regNum = MISCREG_MC5_STATUS;
-            break;
-          case 0x419:
-            regNum = MISCREG_MC6_STATUS;
-            break;
-          case 0x41D:
-            regNum = MISCREG_MC7_STATUS;
-            break;
-          case 0x402:
-            regNum = MISCREG_MC0_ADDR;
-            break;
-          case 0x406:
-            regNum = MISCREG_MC1_ADDR;
-            break;
-          case 0x40A:
-            regNum = MISCREG_MC2_ADDR;
-            break;
-          case 0x40E:
-            regNum = MISCREG_MC3_ADDR;
-            break;
-          case 0x412:
-            regNum = MISCREG_MC4_ADDR;
-            break;
-          case 0x416:
-            regNum = MISCREG_MC5_ADDR;
-            break;
-          case 0x41A:
-            regNum = MISCREG_MC6_ADDR;
-            break;
-          case 0x41E:
-            regNum = MISCREG_MC7_ADDR;
-            break;
-          case 0x403:
-            regNum = MISCREG_MC0_MISC;
-            break;
-          case 0x407:
-            regNum = MISCREG_MC1_MISC;
-            break;
-          case 0x40B:
-            regNum = MISCREG_MC2_MISC;
-            break;
-          case 0x40F:
-            regNum = MISCREG_MC3_MISC;
-            break;
-          case 0x413:
-            regNum = MISCREG_MC4_MISC;
-            break;
-          case 0x417:
-            regNum = MISCREG_MC5_MISC;
-            break;
-          case 0x41B:
-            regNum = MISCREG_MC6_MISC;
-            break;
-          case 0x41F:
-            regNum = MISCREG_MC7_MISC;
-            break;
-          case 0xC0000080:
-            regNum = MISCREG_EFER;
-            break;
-          case 0xC0000081:
-            regNum = MISCREG_STAR;
-            break;
-          case 0xC0000082:
-            regNum = MISCREG_LSTAR;
-            break;
-          case 0xC0000083:
-            regNum = MISCREG_CSTAR;
-            break;
-          case 0xC0000084:
-            regNum = MISCREG_SF_MASK;
-            break;
-          case 0xC0000100:
-            regNum = MISCREG_FS_BASE;
-            break;
-          case 0xC0000101:
-            regNum = MISCREG_GS_BASE;
-            break;
-          case 0xC0000102:
-            regNum = MISCREG_KERNEL_GS_BASE;
-            break;
-          case 0xC0000103:
-            regNum = MISCREG_TSC_AUX;
-            break;
-          case 0xC0010000:
-            regNum = MISCREG_PERF_EVT_SEL0;
-            break;
-          case 0xC0010001:
-            regNum = MISCREG_PERF_EVT_SEL1;
-            break;
-          case 0xC0010002:
-            regNum = MISCREG_PERF_EVT_SEL2;
-            break;
-          case 0xC0010003:
-            regNum = MISCREG_PERF_EVT_SEL3;
-            break;
-          case 0xC0010004:
-            regNum = MISCREG_PERF_EVT_CTR0;
-            break;
-          case 0xC0010005:
-            regNum = MISCREG_PERF_EVT_CTR1;
-            break;
-          case 0xC0010006:
-            regNum = MISCREG_PERF_EVT_CTR2;
-            break;
-          case 0xC0010007:
-            regNum = MISCREG_PERF_EVT_CTR3;
-            break;
-          case 0xC0010010:
-            regNum = MISCREG_SYSCFG;
-            break;
-          case 0xC0010016:
-            regNum = MISCREG_IORR_BASE0;
-            break;
-          case 0xC0010017:
-            regNum = MISCREG_IORR_BASE1;
-            break;
-          case 0xC0010018:
-            regNum = MISCREG_IORR_MASK0;
-            break;
-          case 0xC0010019:
-            regNum = MISCREG_IORR_MASK1;
-            break;
-          case 0xC001001A:
-            regNum = MISCREG_TOP_MEM;
-            break;
-          case 0xC001001D:
-            regNum = MISCREG_TOP_MEM2;
-            break;
-          case 0xC0010114:
-            regNum = MISCREG_VM_CR;
-            break;
-          case 0xC0010115:
-            regNum = MISCREG_IGNNE;
-            break;
-          case 0xC0010116:
-            regNum = MISCREG_SMM_CTL;
-            break;
-          case 0xC0010117:
-            regNum = MISCREG_VM_HSAVE_PA;
-            break;
-          default:
-            return new GeneralProtection(0);
-        }
+        vaddr = (vaddr >> 3) & ~IntAddrPrefixMask;
+        req->setFlags(Request::MMAPPED_IPR);
+
+        MiscRegIndex regNum;
+        if (!msrAddrToIndex(regNum, vaddr))
+            return std::make_shared<GeneralProtection>(0);
+
         //The index is multiplied by the size of a MiscReg so that
         //any memory dependence calculations will not see these as
         //overlapping.
-        req->setPaddr(regNum * sizeof(MiscReg));
+        req->setPaddr((Addr)regNum * sizeof(MiscReg));
         return NoFault;
     } else if (prefix == IntAddrPrefixIO) {
         // TODO If CPL > IOPL or in virtual mode, check the I/O permission
@@ -508,7 +203,7 @@ TLB::translateInt(RequestPtr req, ThreadContext *tc)
         // space.
         assert(!(IOPort & ~0xFFFF));
         if (IOPort == 0xCF8 && req->getSize() == 4) {
-            req->setFlags(Request::MMAPED_IPR);
+            req->setFlags(Request::MMAPPED_IPR);
             req->setPaddr(MISCREG_PCI_CONFIG_ADDRESS * sizeof(MiscReg));
         } else if ((IOPort & ~mask(2)) == 0xCFC) {
             req->setFlags(Request::UNCACHEABLE);
@@ -518,6 +213,8 @@ TLB::translateInt(RequestPtr req, ThreadContext *tc)
                 req->setPaddr(PhysAddrPrefixPciConfig |
                         mbits(configAddress, 30, 2) |
                         (IOPort & mask(2)));
+            } else {
+                req->setPaddr(PhysAddrPrefixIO | IOPort);
             }
         } else {
             req->setFlags(Request::UNCACHEABLE);
@@ -530,6 +227,49 @@ TLB::translateInt(RequestPtr req, ThreadContext *tc)
     }
 }
 
+Fault
+TLB::finalizePhysical(RequestPtr req, ThreadContext *tc, Mode mode) const
+{
+    Addr paddr = req->getPaddr();
+
+    AddrRange m5opRange(0xFFFF0000, 0xFFFFFFFF);
+
+    if (m5opRange.contains(paddr)) {
+        if (m5opRange.contains(paddr)) {
+            req->setFlags(Request::MMAPPED_IPR | Request::GENERIC_IPR);
+            req->setPaddr(GenericISA::iprAddressPseudoInst(
+                            (paddr >> 8) & 0xFF,
+                            paddr & 0xFF));
+        }
+    } else if (FullSystem) {
+        // Check for an access to the local APIC
+        LocalApicBase localApicBase =
+            tc->readMiscRegNoEffect(MISCREG_APIC_BASE);
+        AddrRange apicRange(localApicBase.base * PageBytes,
+                            (localApicBase.base + 1) * PageBytes - 1);
+
+        if (apicRange.contains(paddr)) {
+            // The Intel developer's manuals say the below restrictions apply,
+            // but the linux kernel, because of a compiler optimization, breaks
+            // them.
+            /*
+            // Check alignment
+            if (paddr & ((32/8) - 1))
+                return new GeneralProtection(0);
+            // Check access size
+            if (req->getSize() != (32/8))
+                return new GeneralProtection(0);
+            */
+            // Force the access to be uncacheable.
+            req->setFlags(Request::UNCACHEABLE);
+            req->setPaddr(x86LocalAPICAddress(tc->contextId(),
+                                              paddr - apicRange.start()));
+        }
+    }
+
+    return NoFault;
+}
+
 Fault
 TLB::translate(RequestPtr req, ThreadContext *tc, Translation *translation,
         Mode mode, bool &delayedResponse, bool timing)
@@ -538,13 +278,14 @@ TLB::translate(RequestPtr req, ThreadContext *tc, Translation *translation,
     int seg = flags & SegmentFlagMask;
     bool storeCheck = flags & (StoreCheck << FlagShift);
 
+    delayedResponse = false;
+
     // If this is true, we're dealing with a request to a non-memory address
     // space.
     if (seg == SEGMENT_REG_MS) {
         return translateInt(req, tc);
     }
 
-    delayedResponse = false;
     Addr vaddr = req->getVaddr();
     DPRINTF(TLB, "Translating vaddr %#x.\n", vaddr);
 
@@ -560,99 +301,107 @@ TLB::translate(RequestPtr req, ThreadContext *tc, Translation *translation,
             if (!(seg == SEGMENT_REG_TSG || seg == SYS_SEGMENT_REG_IDTR ||
                         seg == SEGMENT_REG_HS || seg == SEGMENT_REG_LS)
                     && !tc->readMiscRegNoEffect(MISCREG_SEG_SEL(seg)))
-                return new GeneralProtection(0);
+                return std::make_shared<GeneralProtection>(0);
             bool expandDown = false;
             SegAttr attr = tc->readMiscRegNoEffect(MISCREG_SEG_ATTR(seg));
             if (seg >= SEGMENT_REG_ES && seg <= SEGMENT_REG_HS) {
                 if (!attr.writable && (mode == Write || storeCheck))
-                    return new GeneralProtection(0);
+                    return std::make_shared<GeneralProtection>(0);
                 if (!attr.readable && mode == Read)
-                    return new GeneralProtection(0);
+                    return std::make_shared<GeneralProtection>(0);
                 expandDown = attr.expandDown;
 
             }
             Addr base = tc->readMiscRegNoEffect(MISCREG_SEG_BASE(seg));
             Addr limit = tc->readMiscRegNoEffect(MISCREG_SEG_LIMIT(seg));
-            // This assumes we're not in 64 bit mode. If we were, the default
-            // address size is 64 bits, overridable to 32.
-            int size = 32;
             bool sizeOverride = (flags & (AddrSizeFlagBit << FlagShift));
-            SegAttr csAttr = tc->readMiscRegNoEffect(MISCREG_CS_ATTR);
-            if ((csAttr.defaultSize && sizeOverride) ||
-                    (!csAttr.defaultSize && !sizeOverride))
-                size = 16;
-            Addr offset = bits(vaddr - base, size-1, 0);
+            unsigned logSize = sizeOverride ? (unsigned)m5Reg.altAddr
+                                            : (unsigned)m5Reg.defAddr;
+            int size = (1 << logSize) * 8;
+            Addr offset = bits(vaddr - base, size - 1, 0);
             Addr endOffset = offset + req->getSize() - 1;
             if (expandDown) {
                 DPRINTF(TLB, "Checking an expand down segment.\n");
                 warn_once("Expand down segments are untested.\n");
                 if (offset <= limit || endOffset <= limit)
-                    return new GeneralProtection(0);
+                    return std::make_shared<GeneralProtection>(0);
             } else {
                 if (offset > limit || endOffset > limit)
-                    return new GeneralProtection(0);
+                    return std::make_shared<GeneralProtection>(0);
             }
         }
+        if (m5Reg.submode != SixtyFourBitMode ||
+                (flags & (AddrSizeFlagBit << FlagShift)))
+            vaddr &= mask(32);
         // If paging is enabled, do the translation.
         if (m5Reg.paging) {
             DPRINTF(TLB, "Paging enabled.\n");
             // The vaddr already has the segment base applied.
             TlbEntry *entry = lookup(vaddr);
             if (!entry) {
-#if FULL_SYSTEM
-                Fault fault = walker->start(tc, translation, req, mode);
-                if (timing || fault != NoFault) {
-                    // This gets ignored in atomic mode.
-                    delayedResponse = true;
-                    return fault;
-                }
-                entry = lookup(vaddr);
-                assert(entry);
-#else
-                DPRINTF(TLB, "Handling a TLB miss for "
-                        "address %#x at pc %#x.\n",
-                        vaddr, tc->instAddr());
-
-                Process *p = tc->getProcessPtr();
-                TlbEntry newEntry;
-                bool success = p->pTable->lookup(vaddr, newEntry);
-                if (!success && mode != Execute) {
-                    p->checkAndAllocNextPage(vaddr);
-                    success = p->pTable->lookup(vaddr, newEntry);
-                }
-                if (!success) {
-                    return new PageFault(vaddr, true, mode, true, false);
+                if (FullSystem) {
+                    Fault fault = walker->start(tc, translation, req, mode);
+                    if (timing || fault != NoFault) {
+                        // This gets ignored in atomic mode.
+                        delayedResponse = true;
+                        return fault;
+                    }
+                    entry = lookup(vaddr);
+                    assert(entry);
                 } else {
-                    Addr alignedVaddr = p->pTable->pageAlign(vaddr);
-                    DPRINTF(TLB, "Mapping %#x to %#x\n", alignedVaddr,
-                            newEntry.pageStart());
-                    entry = insert(alignedVaddr, newEntry);
+                    DPRINTF(TLB, "Handling a TLB miss for "
+                            "address %#x at pc %#x.\n",
+                            vaddr, tc->instAddr());
+
+                    Process *p = tc->getProcessPtr();
+                    TlbEntry newEntry;
+                    bool success = p->pTable->lookup(vaddr, newEntry);
+                    if (!success && mode != Execute) {
+                        // Check if we just need to grow the stack.
+                        if (p->fixupStackFault(vaddr)) {
+                            // If we did, lookup the entry for the new page.
+                            success = p->pTable->lookup(vaddr, newEntry);
+                        }
+                    }
+                    if (!success) {
+                        return std::make_shared<PageFault>(vaddr, true, mode,
+                                                           true, false);
+                    } else {
+                        Addr alignedVaddr = p->pTable->pageAlign(vaddr);
+                        DPRINTF(TLB, "Mapping %#x to %#x\n", alignedVaddr,
+                                newEntry.pageStart());
+                        entry = insert(alignedVaddr, newEntry);
+                    }
+                    DPRINTF(TLB, "Miss was serviced.\n");
                 }
-                DPRINTF(TLB, "Miss was serviced.\n");
-#endif
             }
+
+            DPRINTF(TLB, "Entry found with paddr %#x, "
+                    "doing protection checks.\n", entry->paddr);
             // Do paging protection checks.
             bool inUser = (m5Reg.cpl == 3 &&
                     !(flags & (CPL0FlagBit << FlagShift)));
-            if ((inUser && !entry->user) ||
-                (mode == Write && !entry->writable)) {
+            CR0 cr0 = tc->readMiscRegNoEffect(MISCREG_CR0);
+            bool badWrite = (!entry->writable && (inUser || cr0.wp));
+            if ((inUser && !entry->user) || (mode == Write && badWrite)) {
                 // The page must have been present to get into the TLB in
                 // the first place. We'll assume the reserved bits are
                 // fine even though we're not checking them.
-                return new PageFault(vaddr, true, mode, inUser, false);
+                return std::make_shared<PageFault>(vaddr, true, mode, inUser,
+                                                   false);
             }
-            if (storeCheck && !entry->writable) {
+            if (storeCheck && badWrite) {
                 // This would fault if this were a write, so return a page
                 // fault that reflects that happening.
-                return new PageFault(vaddr, true, Write, inUser, false);
+                return std::make_shared<PageFault>(vaddr, true, Write, inUser,
+                                                   false);
             }
 
-
-            DPRINTF(TLB, "Entry found with paddr %#x, "
-                    "doing protection checks.\n", entry->paddr);
-            Addr paddr = entry->paddr | (vaddr & (entry->size-1));
+            Addr paddr = entry->paddr | (vaddr & mask(entry->logBytes));
             DPRINTF(TLB, "Translated %#x -> %#x.\n", vaddr, paddr);
             req->setPaddr(paddr);
+            if (entry->uncacheable)
+                req->setFlags(Request::UNCACHEABLE);
         } else {
             //Use the address which already has segmentation applied.
             DPRINTF(TLB, "Paging disabled.\n");
@@ -665,30 +414,9 @@ TLB::translate(RequestPtr req, ThreadContext *tc, Translation *translation,
         DPRINTF(TLB, "Translated %#x -> %#x.\n", vaddr, vaddr);
         req->setPaddr(vaddr);
     }
-    // Check for an access to the local APIC
-#if FULL_SYSTEM
-    LocalApicBase localApicBase = tc->readMiscRegNoEffect(MISCREG_APIC_BASE);
-    Addr baseAddr = localApicBase.base * PageBytes;
-    Addr paddr = req->getPaddr();
-    if (baseAddr <= paddr && baseAddr + PageBytes > paddr) {
-        // The Intel developer's manuals say the below restrictions apply,
-        // but the linux kernel, because of a compiler optimization, breaks
-        // them.
-        /*
-        // Check alignment
-        if (paddr & ((32/8) - 1))
-            return new GeneralProtection(0);
-        // Check access size
-        if (req->getSize() != (32/8))
-            return new GeneralProtection(0);
-        */
-        // Force the access to be uncacheable.
-        req->setFlags(Request::UNCACHEABLE);
-        req->setPaddr(x86LocalAPICAddress(tc->contextId(), paddr - baseAddr));
-    }
-#endif
-    return NoFault;
-};
+
+    return finalizePhysical(req, tc, mode);
+}
 
 Fault
 TLB::translateAtomic(RequestPtr req, ThreadContext *tc, Mode mode)
@@ -709,33 +437,67 @@ TLB::translateTiming(RequestPtr req, ThreadContext *tc,
         translation->finish(fault, req, tc, mode);
 }
 
-#if FULL_SYSTEM
-
-Tick
-TLB::doMmuRegRead(ThreadContext *tc, Packet *pkt)
+Fault
+TLB::translateFunctional(RequestPtr req, ThreadContext *tc, Mode mode)
 {
-    return tc->getCpuPtr()->ticks(1);
+    panic("Not implemented\n");
+    return NoFault;
 }
 
-Tick
-TLB::doMmuRegWrite(ThreadContext *tc, Packet *pkt)
+Walker *
+TLB::getWalker()
 {
-    return tc->getCpuPtr()->ticks(1);
+    return walker;
 }
 
-#endif
-
 void
 TLB::serialize(std::ostream &os)
 {
+    // Only store the entries in use.
+    uint32_t _size = size - freeList.size();
+    SERIALIZE_SCALAR(_size);
+    SERIALIZE_SCALAR(lruSeq);
+
+    uint32_t _count = 0;
+
+    for (uint32_t x = 0; x < size; x++) {
+        if (tlb[x].trieHandle != NULL) {
+            os << "\n[" << csprintf("%s.Entry%d", name(), _count) << "]\n";
+            tlb[x].serialize(os);
+            _count++;
+        }
+    }
 }
 
 void
 TLB::unserialize(Checkpoint *cp, const std::string &section)
 {
+    // Do not allow to restore with a smaller tlb.
+    uint32_t _size;
+    UNSERIALIZE_SCALAR(_size);
+    if (_size > size) {
+        fatal("TLB size less than the one in checkpoint!");
+    }
+
+    UNSERIALIZE_SCALAR(lruSeq);
+
+    for (uint32_t x = 0; x < _size; x++) {
+        TlbEntry *newEntry = freeList.front();
+        freeList.pop_front();
+
+        newEntry->unserialize(cp, csprintf("%s.Entry%d", name(), x));
+        newEntry->trieHandle = trie.insert(newEntry->vaddr,
+            TlbEntryTrie::MaxBits - newEntry->logBytes, newEntry);
+    }
+}
+
+BaseMasterPort *
+TLB::getMasterPort()
+{
+    return &walker->getMasterPort("port");
 }
 
-/* end namespace X86ISA */ }
+} // namespace X86ISA
 
 X86ISA::TLB *
 X86TLBParams::create()