Address translation: Make the page table more flexible.

The page table now stores actual page table entries. It is still a templated
class here, but this will be corrected in the near future.

--HG--
extra : convert_revision : 804dcc6320414c2b3ab76a74a15295bd24e1d13d

7 files changed, 133 insertions, 129 deletions

diff --git a/src/arch/alpha/ev5.cc b/src/arch/alpha/ev5.cc
index 123506e40..5dc49623e 100644
--- a/src/arch/alpha/ev5.cc
+++ b/src/arch/alpha/ev5.cc
@@ -245,15 +245,16 @@ AlphaISA::MiscRegFile::readIpr(int idx, ThreadContext *tc)
 
       case AlphaISA::IPR_DTB_PTE:
         {
-            AlphaISA::PTE &pte = tc->getDTBPtr()->index(!tc->misspeculating());
-
-            retval |= ((uint64_t)pte.ppn & ULL(0x7ffffff)) << 32;
-            retval |= ((uint64_t)pte.xre & ULL(0xf)) << 8;
-            retval |= ((uint64_t)pte.xwe & ULL(0xf)) << 12;
-            retval |= ((uint64_t)pte.fonr & ULL(0x1)) << 1;
-            retval |= ((uint64_t)pte.fonw & ULL(0x1))<< 2;
-            retval |= ((uint64_t)pte.asma & ULL(0x1)) << 4;
-            retval |= ((uint64_t)pte.asn & ULL(0x7f)) << 57;
+            AlphaISA::TlbEntry &entry
+                = tc->getDTBPtr()->index(!tc->misspeculating());
+
+            retval |= ((uint64_t)entry.ppn & ULL(0x7ffffff)) << 32;
+            retval |= ((uint64_t)entry.xre & ULL(0xf)) << 8;
+            retval |= ((uint64_t)entry.xwe & ULL(0xf)) << 12;
+            retval |= ((uint64_t)entry.fonr & ULL(0x1)) << 1;
+            retval |= ((uint64_t)entry.fonw & ULL(0x1))<< 2;
+            retval |= ((uint64_t)entry.asma & ULL(0x1)) << 4;
+            retval |= ((uint64_t)entry.asn & ULL(0x7f)) << 57;
         }
         break;
 
@@ -480,7 +481,7 @@ AlphaISA::MiscRegFile::setIpr(int idx, uint64_t val, ThreadContext *tc)
         break;
 
       case AlphaISA::IPR_DTB_TAG: {
-          struct AlphaISA::PTE pte;
+          struct AlphaISA::TlbEntry entry;
 
           // FIXME: granularity hints NYI...
           if (EV5::DTB_PTE_GH(ipr[AlphaISA::IPR_DTB_PTE]) != 0)
@@ -490,21 +491,21 @@ AlphaISA::MiscRegFile::setIpr(int idx, uint64_t val, ThreadContext *tc)
           ipr[idx] = val;
 
           // construct PTE for new entry
-          pte.ppn = EV5::DTB_PTE_PPN(ipr[AlphaISA::IPR_DTB_PTE]);
-          pte.xre = EV5::DTB_PTE_XRE(ipr[AlphaISA::IPR_DTB_PTE]);
-          pte.xwe = EV5::DTB_PTE_XWE(ipr[AlphaISA::IPR_DTB_PTE]);
-          pte.fonr = EV5::DTB_PTE_FONR(ipr[AlphaISA::IPR_DTB_PTE]);
-          pte.fonw = EV5::DTB_PTE_FONW(ipr[AlphaISA::IPR_DTB_PTE]);
-          pte.asma = EV5::DTB_PTE_ASMA(ipr[AlphaISA::IPR_DTB_PTE]);
-          pte.asn = EV5::DTB_ASN_ASN(ipr[AlphaISA::IPR_DTB_ASN]);
+          entry.ppn = EV5::DTB_PTE_PPN(ipr[AlphaISA::IPR_DTB_PTE]);
+          entry.xre = EV5::DTB_PTE_XRE(ipr[AlphaISA::IPR_DTB_PTE]);
+          entry.xwe = EV5::DTB_PTE_XWE(ipr[AlphaISA::IPR_DTB_PTE]);
+          entry.fonr = EV5::DTB_PTE_FONR(ipr[AlphaISA::IPR_DTB_PTE]);
+          entry.fonw = EV5::DTB_PTE_FONW(ipr[AlphaISA::IPR_DTB_PTE]);
+          entry.asma = EV5::DTB_PTE_ASMA(ipr[AlphaISA::IPR_DTB_PTE]);
+          entry.asn = EV5::DTB_ASN_ASN(ipr[AlphaISA::IPR_DTB_ASN]);
 
           // insert new TAG/PTE value into data TLB
-          tc->getDTBPtr()->insert(val, pte);
+          tc->getDTBPtr()->insert(val, entry);
       }
         break;
 
       case AlphaISA::IPR_ITB_PTE: {
-          struct AlphaISA::PTE pte;
+          struct AlphaISA::TlbEntry entry;
 
           // FIXME: granularity hints NYI...
           if (EV5::ITB_PTE_GH(val) != 0)
@@ -514,16 +515,16 @@ AlphaISA::MiscRegFile::setIpr(int idx, uint64_t val, ThreadContext *tc)
           ipr[idx] = val;
 
           // construct PTE for new entry
-          pte.ppn = EV5::ITB_PTE_PPN(val);
-          pte.xre = EV5::ITB_PTE_XRE(val);
-          pte.xwe = 0;
-          pte.fonr = EV5::ITB_PTE_FONR(val);
-          pte.fonw = EV5::ITB_PTE_FONW(val);
-          pte.asma = EV5::ITB_PTE_ASMA(val);
-          pte.asn = EV5::ITB_ASN_ASN(ipr[AlphaISA::IPR_ITB_ASN]);
+          entry.ppn = EV5::ITB_PTE_PPN(val);
+          entry.xre = EV5::ITB_PTE_XRE(val);
+          entry.xwe = 0;
+          entry.fonr = EV5::ITB_PTE_FONR(val);
+          entry.fonw = EV5::ITB_PTE_FONW(val);
+          entry.asma = EV5::ITB_PTE_ASMA(val);
+          entry.asn = EV5::ITB_ASN_ASN(ipr[AlphaISA::IPR_ITB_ASN]);
 
           // insert new TAG/PTE value into data TLB
-          tc->getITBPtr()->insert(ipr[AlphaISA::IPR_ITB_TAG], pte);
+          tc->getITBPtr()->insert(ipr[AlphaISA::IPR_ITB_TAG], entry);
       }
         break;
 
diff --git a/src/arch/alpha/faults.cc b/src/arch/alpha/faults.cc
index d81b55b33..7d4de902a 100644
--- a/src/arch/alpha/faults.cc
+++ b/src/arch/alpha/faults.cc
@@ -185,18 +185,18 @@ void ItbPageFault::invoke(ThreadContext * tc)
         VAddr vaddr(pc);
         VAddr paddr(physaddr);
 
-        PTE pte;
-        pte.tag = vaddr.vpn();
-        pte.ppn = paddr.vpn();
-        pte.xre = 15; //This can be read in all modes.
-        pte.xwe = 1; //This can be written only in kernel mode.
-        pte.asn = p->M5_pid; //Address space number.
-        pte.asma = false; //Only match on this ASN.
-        pte.fonr = false; //Don't fault on read.
-        pte.fonw = false; //Don't fault on write.
-        pte.valid = true; //This entry is valid.
-
-        tc->getITBPtr()->insert(vaddr.page(), pte);
+        TlbEntry entry;
+        entry.tag = vaddr.vpn();
+        entry.ppn = paddr.vpn();
+        entry.xre = 15; //This can be read in all modes.
+        entry.xwe = 1; //This can be written only in kernel mode.
+        entry.asn = p->M5_pid; //Address space number.
+        entry.asma = false; //Only match on this ASN.
+        entry.fonr = false; //Don't fault on read.
+        entry.fonw = false; //Don't fault on write.
+        entry.valid = true; //This entry is valid.
+
+        tc->getITBPtr()->insert(vaddr.page(), entry);
     }
 }
 
@@ -214,18 +214,18 @@ void NDtbMissFault::invoke(ThreadContext * tc)
     } else {
         VAddr paddr(physaddr);
 
-        PTE pte;
-        pte.tag = vaddr.vpn();
-        pte.ppn = paddr.vpn();
-        pte.xre = 15; //This can be read in all modes.
-        pte.xwe = 15; //This can be written in all modes.
-        pte.asn = p->M5_pid; //Address space number.
-        pte.asma = false; //Only match on this ASN.
-        pte.fonr = false; //Don't fault on read.
-        pte.fonw = false; //Don't fault on write.
-        pte.valid = true; //This entry is valid.
-
-        tc->getDTBPtr()->insert(vaddr.page(), pte);
+        TlbEntry entry;
+        entry.tag = vaddr.vpn();
+        entry.ppn = paddr.vpn();
+        entry.xre = 15; //This can be read in all modes.
+        entry.xwe = 15; //This can be written in all modes.
+        entry.asn = p->M5_pid; //Address space number.
+        entry.asma = false; //Only match on this ASN.
+        entry.fonr = false; //Don't fault on read.
+        entry.fonw = false; //Don't fault on write.
+        entry.valid = true; //This entry is valid.
+
+        tc->getDTBPtr()->insert(vaddr.page(), entry);
     }
 }
 
diff --git a/src/arch/alpha/faults.hh b/src/arch/alpha/faults.hh
index 49ba25966..74699b2b5 100644
--- a/src/arch/alpha/faults.hh
+++ b/src/arch/alpha/faults.hh
@@ -88,11 +88,6 @@ static inline Fault genMachineCheckFault()
     return new MachineCheckFault;
 }
 
-static inline Fault genAlignmentFault()
-{
-    return new AlignmentFault;
-}
-
 class ResetFault : public AlphaFault
 {
   private:
diff --git a/src/arch/alpha/pagetable.cc b/src/arch/alpha/pagetable.cc
index 0c26ccbe3..3f9537834 100644
--- a/src/arch/alpha/pagetable.cc
+++ b/src/arch/alpha/pagetable.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2006 The Regents of The University of Michigan
+ * Copyright (c) 2006-2007 The Regents of The University of Michigan
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
@@ -34,7 +34,7 @@
 namespace AlphaISA
 {
     void
-    PTE::serialize(std::ostream &os)
+    TlbEntry::serialize(std::ostream &os)
     {
         SERIALIZE_SCALAR(tag);
         SERIALIZE_SCALAR(ppn);
@@ -48,7 +48,7 @@ namespace AlphaISA
     }
 
     void
-    PTE::unserialize(Checkpoint *cp, const std::string &section)
+    TlbEntry::unserialize(Checkpoint *cp, const std::string &section)
     {
         UNSERIALIZE_SCALAR(tag);
         UNSERIALIZE_SCALAR(ppn);
diff --git a/src/arch/alpha/pagetable.hh b/src/arch/alpha/pagetable.hh
index c7e1c8923..0b885bc36 100644
--- a/src/arch/alpha/pagetable.hh
+++ b/src/arch/alpha/pagetable.hh
@@ -89,9 +89,14 @@ namespace AlphaISA {
         Addr paddr() const { return _pfn() << PageShift; }
     };
 
-    // ITB/DTB page table entry
-    struct PTE
+    // ITB/DTB table entry
+    struct TlbEntry
     {
+        //Construct an entry that maps to physical address addr.
+        TlbEntry(Addr addr)
+        {
+        }
+
         Addr tag;			// virtual page number tag
         Addr ppn;			// physical page number
         uint8_t xre;		// read permissions - VMEM_PERM_* mask
diff --git a/src/arch/alpha/tlb.cc b/src/arch/alpha/tlb.cc
index f701c423d..628d7ad6b 100644
--- a/src/arch/alpha/tlb.cc
+++ b/src/arch/alpha/tlb.cc
@@ -62,8 +62,8 @@ bool uncacheBit40 = false;
 TLB::TLB(const string &name, int s)
     : SimObject(name), size(s), nlu(0)
 {
-    table = new PTE[size];
-    memset(table, 0, sizeof(PTE[size]));
+    table = new TlbEntry[size];
+    memset(table, 0, sizeof(TlbEntry[size]));
     flushCache();
 }
 
@@ -74,23 +74,23 @@ TLB::~TLB()
 }
 
 // look up an entry in the TLB
-PTE *
+TlbEntry *
 TLB::lookup(Addr vpn, uint8_t asn)
 {
     // assume not found...
-    PTE *retval = NULL;
-
-    if (PTECache[0]) {
-        if (vpn == PTECache[0]->tag &&
-            (PTECache[0]->asma || PTECache[0]->asn == asn))
-            retval = PTECache[0];
-        else if (PTECache[1]) {
-            if (vpn == PTECache[1]->tag &&
-                (PTECache[1]->asma || PTECache[1]->asn == asn))
-                retval = PTECache[1];
-            else if (PTECache[2] && vpn == PTECache[2]->tag &&
-                     (PTECache[2]->asma || PTECache[2]->asn == asn))
-                retval = PTECache[2];
+    TlbEntry *retval = NULL;
+
+    if (EntryCache[0]) {
+        if (vpn == EntryCache[0]->tag &&
+            (EntryCache[0]->asma || EntryCache[0]->asn == asn))
+            retval = EntryCache[0];
+        else if (EntryCache[1]) {
+            if (vpn == EntryCache[1]->tag &&
+                (EntryCache[1]->asma || EntryCache[1]->asn == asn))
+                retval = EntryCache[1];
+            else if (EntryCache[2] && vpn == EntryCache[2]->tag &&
+                     (EntryCache[2]->asma || EntryCache[2]->asn == asn))
+                retval = EntryCache[2];
         }
     }
 
@@ -99,10 +99,10 @@ TLB::lookup(Addr vpn, uint8_t asn)
         if (i != lookupTable.end()) {
             while (i->first == vpn) {
                 int index = i->second;
-                PTE *pte = &table[index];
-                assert(pte->valid);
-                if (vpn == pte->tag && (pte->asma || pte->asn == asn)) {
-                    retval = updateCache(pte);
+                TlbEntry *entry = &table[index];
+                assert(entry->valid);
+                if (vpn == entry->tag && (entry->asma || entry->asn == asn)) {
+                    retval = updateCache(entry);
                     break;
                 }
 
@@ -157,7 +157,7 @@ TLB::checkCacheability(RequestPtr &req)
 
 // insert a new TLB entry
 void
-TLB::insert(Addr addr, PTE &pte)
+TLB::insert(Addr addr, TlbEntry &entry)
 {
     flushCache();
     VAddr vaddr = addr;
@@ -181,9 +181,9 @@ TLB::insert(Addr addr, PTE &pte)
         lookupTable.erase(i);
     }
 
-    DPRINTF(TLB, "insert @%d: %#x -> %#x\n", nlu, vaddr.vpn(), pte.ppn);
+    DPRINTF(TLB, "insert @%d: %#x -> %#x\n", nlu, vaddr.vpn(), entry.ppn);
 
-    table[nlu] = pte;
+    table[nlu] = entry;
     table[nlu].tag = vaddr.vpn();
     table[nlu].valid = true;
 
@@ -195,7 +195,7 @@ void
 TLB::flushAll()
 {
     DPRINTF(TLB, "flushAll\n");
-    memset(table, 0, sizeof(PTE[size]));
+    memset(table, 0, sizeof(TlbEntry[size]));
     flushCache();
     lookupTable.clear();
     nlu = 0;
@@ -209,17 +209,17 @@ TLB::flushProcesses()
     PageTable::iterator end = lookupTable.end();
     while (i != end) {
         int index = i->second;
-        PTE *pte = &table[index];
-        assert(pte->valid);
+        TlbEntry *entry = &table[index];
+        assert(entry->valid);
 
         // we can't increment i after we erase it, so save a copy and
         // increment it to get the next entry now
         PageTable::iterator cur = i;
         ++i;
 
-        if (!pte->asma) {
-            DPRINTF(TLB, "flush @%d: %#x -> %#x\n", index, pte->tag, pte->ppn);
-            pte->valid = false;
+        if (!entry->asma) {
+            DPRINTF(TLB, "flush @%d: %#x -> %#x\n", index, entry->tag, entry->ppn);
+            entry->valid = false;
             lookupTable.erase(cur);
         }
     }
@@ -237,15 +237,15 @@ TLB::flushAddr(Addr addr, uint8_t asn)
 
     while (i != lookupTable.end() && i->first == vaddr.vpn()) {
         int index = i->second;
-        PTE *pte = &table[index];
-        assert(pte->valid);
+        TlbEntry *entry = &table[index];
+        assert(entry->valid);
 
-        if (vaddr.vpn() == pte->tag && (pte->asma || pte->asn == asn)) {
+        if (vaddr.vpn() == entry->tag && (entry->asma || entry->asn == asn)) {
             DPRINTF(TLB, "flushaddr @%d: %#x -> %#x\n", index, vaddr.vpn(),
-                    pte->ppn);
+                    entry->ppn);
 
             // invalidate this entry
-            pte->valid = false;
+            entry->valid = false;
 
             lookupTable.erase(i++);
         } else {
@@ -262,7 +262,7 @@ TLB::serialize(ostream &os)
     SERIALIZE_SCALAR(nlu);
 
     for (int i = 0; i < size; i++) {
-        nameOut(os, csprintf("%s.PTE%d", name(), i));
+        nameOut(os, csprintf("%s.Entry%d", name(), i));
         table[i].serialize(os);
     }
 }
@@ -274,7 +274,7 @@ TLB::unserialize(Checkpoint *cp, const string &section)
     UNSERIALIZE_SCALAR(nlu);
 
     for (int i = 0; i < size; i++) {
-        table[i].unserialize(cp, csprintf("%s.PTE%d", section, i));
+        table[i].unserialize(cp, csprintf("%s.Entry%d", section, i));
         if (table[i].valid) {
             lookupTable.insert(make_pair(table[i].tag, i));
         }
@@ -364,20 +364,20 @@ ITB::translate(RequestPtr &req, ThreadContext *tc)
         } else {
             // not a physical address: need to look up pte
             int asn = DTB_ASN_ASN(tc->readMiscRegNoEffect(IPR_DTB_ASN));
-            PTE *pte = lookup(VAddr(req->getVaddr()).vpn(),
+            TlbEntry *entry = lookup(VAddr(req->getVaddr()).vpn(),
                               asn);
 
-            if (!pte) {
+            if (!entry) {
                 misses++;
                 return new ItbPageFault(req->getVaddr());
             }
 
-            req->setPaddr((pte->ppn << PageShift) +
+            req->setPaddr((entry->ppn << PageShift) +
                           (VAddr(req->getVaddr()).offset()
                            & ~3));
 
             // check permissions for this access
-            if (!(pte->xre &
+            if (!(entry->xre &
                   (1 << ICM_CM(tc->readMiscRegNoEffect(IPR_ICM))))) {
                 // instruction access fault
                 acv++;
@@ -548,10 +548,9 @@ DTB::translate(RequestPtr &req, ThreadContext *tc, bool write)
             int asn = DTB_ASN_ASN(tc->readMiscRegNoEffect(IPR_DTB_ASN));
 
             // not a physical address: need to look up pte
-            PTE *pte = lookup(VAddr(req->getVaddr()).vpn(),
-                              asn);
+            TlbEntry *entry = lookup(VAddr(req->getVaddr()).vpn(), asn);
 
-            if (!pte) {
+            if (!entry) {
                 // page fault
                 if (write) { write_misses++; } else { read_misses++; }
                 uint64_t flags = (write ? MM_STAT_WR_MASK : 0) |
@@ -563,32 +562,32 @@ DTB::translate(RequestPtr &req, ThreadContext *tc, bool write)
                                               flags));
             }
 
-            req->setPaddr((pte->ppn << PageShift) +
+            req->setPaddr((entry->ppn << PageShift) +
                           VAddr(req->getVaddr()).offset());
 
             if (write) {
-                if (!(pte->xwe & MODE2MASK(mode))) {
+                if (!(entry->xwe & MODE2MASK(mode))) {
                     // declare the instruction access fault
                     write_acv++;
                     uint64_t flags = MM_STAT_WR_MASK |
                         MM_STAT_ACV_MASK |
-                        (pte->fonw ? MM_STAT_FONW_MASK : 0);
+                        (entry->fonw ? MM_STAT_FONW_MASK : 0);
                     return new DtbPageFault(req->getVaddr(), req->getFlags(), flags);
                 }
-                if (pte->fonw) {
+                if (entry->fonw) {
                     write_acv++;
                     uint64_t flags = MM_STAT_WR_MASK |
                         MM_STAT_FONW_MASK;
                     return new DtbPageFault(req->getVaddr(), req->getFlags(), flags);
                 }
             } else {
-                if (!(pte->xre & MODE2MASK(mode))) {
+                if (!(entry->xre & MODE2MASK(mode))) {
                     read_acv++;
                     uint64_t flags = MM_STAT_ACV_MASK |
-                        (pte->fonr ? MM_STAT_FONR_MASK : 0);
+                        (entry->fonr ? MM_STAT_FONR_MASK : 0);
                     return new DtbAcvFault(req->getVaddr(), req->getFlags(), flags);
                 }
-                if (pte->fonr) {
+                if (entry->fonr) {
                     read_acv++;
                     uint64_t flags = MM_STAT_FONR_MASK;
                     return new DtbPageFault(req->getVaddr(), req->getFlags(), flags);
@@ -609,15 +608,15 @@ DTB::translate(RequestPtr &req, ThreadContext *tc, bool write)
     return checkCacheability(req);
 }
 
-PTE &
+TlbEntry &
 TLB::index(bool advance)
 {
-    PTE *pte = &table[nlu];
+    TlbEntry *entry = &table[nlu];
 
     if (advance)
         nextnlu();
 
-    return *pte;
+    return *entry;
 }
 
 /* end namespace AlphaISA */ }
diff --git a/src/arch/alpha/tlb.hh b/src/arch/alpha/tlb.hh
index a4255f3c5..8df47dbec 100644
--- a/src/arch/alpha/tlb.hh
+++ b/src/arch/alpha/tlb.hh
@@ -48,20 +48,20 @@ class ThreadContext;
 
 namespace AlphaISA
 {
-    class PTE;
+    class TlbEntry;
 
     class TLB : public SimObject
     {
       protected:
         typedef std::multimap<Addr, int> PageTable;
-        PageTable lookupTable;	// Quick lookup into page table
+        PageTable lookupTable;  // Quick lookup into page table
 
-        PTE *table;	// the Page Table
-        int size;			// TLB Size
-        int nlu;			// not last used entry (for replacement)
+        TlbEntry *table;        // the Page Table
+        int size;               // TLB Size
+        int nlu;                // not last used entry (for replacement)
 
         void nextnlu() { if (++nlu >= size) nlu = 0; }
-        PTE *lookup(Addr vpn, uint8_t asn);
+        TlbEntry *lookup(Addr vpn, uint8_t asn);
 
       public:
         TLB(const std::string &name, int size);
@@ -69,8 +69,8 @@ namespace AlphaISA
 
         int getsize() const { return size; }
 
-        PTE &index(bool advance = true);
-        void insert(Addr vaddr, PTE &pte);
+        TlbEntry &index(bool advance = true);
+        void insert(Addr vaddr, TlbEntry &entry);
 
         void flushAll();
         void flushProcesses();
@@ -90,13 +90,17 @@ namespace AlphaISA
         virtual void unserialize(Checkpoint *cp, const std::string &section);
 
         // Most recently used page table entries
-        PTE *PTECache[3];
-        inline void flushCache() { memset(PTECache, 0, 3 * sizeof(PTE*)); }
-        inline PTE* updateCache(PTE *pte) {
-            PTECache[2] = PTECache[1];
-            PTECache[1] = PTECache[0];
-            PTECache[0] = pte;
-            return pte;
+        TlbEntry *EntryCache[3];
+        inline void flushCache()
+        {
+            memset(EntryCache, 0, 3 * sizeof(TlbEntry*));
+        }
+
+        inline TlbEntry* updateCache(TlbEntry *entry) {
+            EntryCache[2] = EntryCache[1];
+            EntryCache[1] = EntryCache[0];
+            EntryCache[0] = entry;
+            return entry;
         }
     };