mmu.hh

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 *
 * The license below extends only to copyright in the software and shall
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 * terms below provided that you ensure that this notice is replicated
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 * modified or unmodified, in source code or in binary form.
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 * met: redistributions of source code must retain the above copyright
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#ifndef __ARCH_GENERIC_MMU_HH__
#define __ARCH_GENERIC_MMU_HH__
 
#include <set>
 
#include "mem/request.hh"
#include "mem/translation_gen.hh"
#include "params/BaseMMU.hh"
#include "sim/sim_object.hh"
 
namespace gem5
{
 
class BaseTLB;
 
class BaseMMU : public SimObject
{
  public:
    enum Mode { Read, Write, Execute };
 
    class Translation
    {
      public:
        virtual ~Translation()
        {}
 
        virtual void markDelayed() = 0;
 
        /*
         * The memory for this object may be dynamically allocated, and it may
         * be responsible for cleaning itself up which will happen in this
         * function. Once it's called, the object is no longer valid.
         */
        virtual void finish(const Fault &fault, const RequestPtr &req,
                            ThreadContext *tc, BaseMMU::Mode mode) = 0;
 
        virtual bool squashed() const { return false; }
    };
 
  protected:
    typedef BaseMMUParams Params;
 
    BaseMMU(const Params &p)
      : SimObject(p), dtb(p.dtb), itb(p.itb)
    {}
 
    BaseTLB*
    getTlb(Mode mode) const
    {
        if (mode == Execute)
            return itb;
        else
            return dtb;
    }
 
  public:
    void init() override;
 
    virtual void flushAll();
 
    void demapPage(Addr vaddr, uint64_t asn);
 
    virtual Fault
    translateAtomic(const RequestPtr &req, ThreadContext *tc,
                    Mode mode);
 
    virtual void
    translateTiming(const RequestPtr &req, ThreadContext *tc,
                    Translation *translation, Mode mode);
 
    virtual Fault
    translateFunctional(const RequestPtr &req, ThreadContext *tc,
                        Mode mode);
 
    class MMUTranslationGen : public TranslationGen
    {
      private:
        ThreadContext *tc;
        ContextID cid;
        BaseMMU *mmu;
        BaseMMU::Mode mode;
        Request::Flags flags;
        const Addr pageBytes;
 
        void translate(Range &range) const override;
 
      public:
        MMUTranslationGen(Addr page_bytes, Addr new_start, Addr new_size,
                ThreadContext *new_tc, BaseMMU *new_mmu,
                BaseMMU::Mode new_mode, Request::Flags new_flags);
    };
 
    virtual TranslationGenPtr translateFunctional(Addr start, Addr size,
            ThreadContext *tc, BaseMMU::Mode mode, Request::Flags flags) = 0;
 
    virtual Fault
    finalizePhysical(const RequestPtr &req, ThreadContext *tc,
                     Mode mode) const;
 
    virtual void takeOverFrom(BaseMMU *old_mmu);
 
  public:
    BaseTLB* dtb;
    BaseTLB* itb;
 
  protected:
    std::set<BaseTLB*> instruction;
    std::set<BaseTLB*> data;
    std::set<BaseTLB*> unified;
 
};
 
} // namespace gem5
 
#endif