simple_mem.hh

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#ifndef __MEM_SIMPLE_MEMORY_HH__
#define __MEM_SIMPLE_MEMORY_HH__
 
#include <list>
 
#include "base/random.hh"
#include "mem/abstract_mem.hh"
#include "mem/port.hh"
#include "params/SimpleMemory.hh"
 
namespace gem5
{
 
namespace memory
{

class SimpleMemory : public AbstractMemory
{
 
  private:

    class DeferredPacket
    {
 
      public:
 
        const Tick tick;
        const PacketPtr pkt;
 
        DeferredPacket(PacketPtr _pkt, Tick _tick) : tick(_tick), pkt(_pkt)
        { }
    };
 
    class MemoryPort : public ResponsePort
    {
      private:
        SimpleMemory& mem;
 
      public:
        MemoryPort(const std::string& _name, SimpleMemory& _memory);
 
      protected:
        Tick recvAtomic(PacketPtr pkt) override;
        Tick recvAtomicBackdoor(
                PacketPtr pkt, MemBackdoorPtr &_backdoor) override;
        void recvFunctional(PacketPtr pkt) override;
        void recvMemBackdoorReq(const MemBackdoorReq &req,
                MemBackdoorPtr &backdoor) override;
        bool recvTimingReq(PacketPtr pkt) override;
        void recvRespRetry() override;
        AddrRangeList getAddrRanges() const override;
    };
 
    MemoryPort port;

    const Tick latency;

    const Tick latency_var;

    std::list<DeferredPacket> packetQueue;

    const double bandwidth;

    bool isBusy;

    bool retryReq;

    bool retryResp;
 
    mutable Random::RandomPtr rng = Random::genRandom();

    void release();
 
    EventFunctionWrapper releaseEvent;

    void dequeue();
 
    EventFunctionWrapper dequeueEvent;

    Tick getLatency() const;

    std::unique_ptr<Packet> pendingDelete;
 
  public:
 
    SimpleMemory(const SimpleMemoryParams &p);
 
    DrainState drain() override;
 
    Port &getPort(const std::string &if_name,
                  PortID idx=InvalidPortID) override;
    void init() override;
 
  protected:
    Tick recvAtomic(PacketPtr pkt);
    Tick recvAtomicBackdoor(PacketPtr pkt, MemBackdoorPtr &_backdoor);
    void recvFunctional(PacketPtr pkt);
    void recvMemBackdoorReq(const MemBackdoorReq &req,
            MemBackdoorPtr &backdoor);
    bool recvTimingReq(PacketPtr pkt);
    void recvRespRetry();
};
 
} // namespace memory
} // namespace gem5
 
#endif //__MEM_SIMPLE_MEMORY_HH__