gem5/src/arch/mips/tlb.hh
Gabe Black 8b4796a367 TLB: Make a TLB base class and put a virtual demapPage function in it.
--HG--
extra : convert_revision : cc0e62a5a337fd5bf332ad33bed61c0d505a936f
2008-02-26 23:38:51 -05:00

167 lines
4.9 KiB
C++

/*
* Copyright (c) 2001-2005 The Regents of The University of Michigan
* Copyright (c) 2007 MIPS Technologies, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Nathan Binkert
* Steve Reinhardt
* Jaidev Patwardhan
* Korey Sewell
*/
#ifndef __ARCH_MIPS_TLB_HH__
#define __ARCH_MIPS_TLB_HH__
#include <map>
#include "arch/mips/isa_traits.hh"
#include "arch/mips/utility.hh"
#include "arch/mips/vtophys.hh"
#include "arch/mips/pagetable.hh"
#include "base/statistics.hh"
#include "mem/request.hh"
#include "params/MipsDTB.hh"
#include "params/MipsITB.hh"
#include "sim/faults.hh"
#include "sim/tlb.hh"
#include "sim/sim_object.hh"
class ThreadContext;
/* MIPS does not distinguish between a DTLB and an ITLB -> unified TLB
However, to maintain compatibility with other architectures, we'll
simply create an ITLB and DTLB that will point to the real TLB */
namespace MipsISA {
// WARN: This particular TLB entry is not necessarily conformed to MIPS ISA
struct TlbEntry
{
Addr _pageStart;
TlbEntry() {}
TlbEntry(Addr asn, Addr vaddr, Addr paddr) : _pageStart(paddr) {}
Addr pageStart()
{
return _pageStart;
}
void serialize(std::ostream &os)
{
SERIALIZE_SCALAR(_pageStart);
}
void unserialize(Checkpoint *cp, const std::string &section)
{
UNSERIALIZE_SCALAR(_pageStart);
}
};
class TLB : public BaseTLB
{
protected:
typedef std::multimap<Addr, int> PageTable;
PageTable lookupTable; // Quick lookup into page table
MipsISA::PTE *table; // the Page Table
int size; // TLB Size
int nlu; // not last used entry (for replacement)
void nextnlu() { if (++nlu >= size) nlu = 0; }
MipsISA::PTE *lookup(Addr vpn, uint8_t asn) const;
mutable Stats::Scalar<> read_hits;
mutable Stats::Scalar<> read_misses;
mutable Stats::Scalar<> read_acv;
mutable Stats::Scalar<> read_accesses;
mutable Stats::Scalar<> write_hits;
mutable Stats::Scalar<> write_misses;
mutable Stats::Scalar<> write_acv;
mutable Stats::Scalar<> write_accesses;
Stats::Formula hits;
Stats::Formula misses;
Stats::Formula invalids;
Stats::Formula accesses;
public:
typedef MipsTLBParams Params;
TLB(const Params *p);
int probeEntry(Addr vpn,uint8_t) const;
MipsISA::PTE *getEntry(unsigned) const;
virtual ~TLB();
int smallPages;
int getsize() const { return size; }
MipsISA::PTE &index(bool advance = true);
void insert(Addr vaddr, MipsISA::PTE &pte);
void insertAt(MipsISA::PTE &pte, unsigned Index, int _smallPages);
void flushAll();
void demapPage(Addr vaddr, uint64_t asn)
{
panic("demapPage unimplemented.\n");
}
// static helper functions... really
static bool validVirtualAddress(Addr vaddr);
static Fault checkCacheability(RequestPtr &req);
// Checkpointing
void serialize(std::ostream &os);
void unserialize(Checkpoint *cp, const std::string &section);
void regStats();
};
class ITB : public TLB {
public:
typedef MipsTLBParams Params;
ITB(const Params *p);
Fault translate(RequestPtr &req, ThreadContext *tc);
};
class DTB : public TLB {
public:
typedef MipsTLBParams Params;
DTB(const Params *p);
Fault translate(RequestPtr &req, ThreadContext *tc, bool write = false);
};
class UTB : public ITB, public DTB {
public:
typedef MipsTLBParams Params;
UTB(const Params *p);
};
}
#endif // __MIPS_MEMORY_HH__