packet_queue.hh

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 * Copyright (c) 2006 The Regents of The University of Michigan
 * All rights reserved.
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#ifndef __MEM_PACKET_QUEUE_HH__
#define __MEM_PACKET_QUEUE_HH__

#include <list>

#include "mem/port.hh"
#include "sim/drain.hh"
#include "sim/eventq.hh"

class PacketQueue : public Drainable
{
  private:
    class DeferredPacket {
      public:
        Tick tick;      
        PacketPtr pkt;  
        DeferredPacket(Tick t, PacketPtr p)
            : tick(t), pkt(p)
        {}
    };

    typedef std::list<DeferredPacket> DeferredPacketList;

    DeferredPacketList transmitList;

    EventManager& em;

    void processSendEvent();

    EventFunctionWrapper sendEvent;

     /*
      * Optionally disable the sanity check
      * on the size of the transmitList. The
      * sanity check will be enabled by default.
      */
    bool _disableSanityCheck;

    bool forceOrder;

  protected:

    const std::string label;

    bool waitingOnRetry;

    bool deferredPacketReady() const
    { return !transmitList.empty() && transmitList.front().tick <= curTick(); }

    virtual void sendDeferredPacket();

    virtual bool sendTiming(PacketPtr pkt) = 0;

    PacketQueue(EventManager& _em, const std::string& _label,
                const std::string& _sendEventName,
                bool force_order = false,
                bool disable_sanity_check = false);

    virtual ~PacketQueue();

  public:

    virtual const std::string name() const = 0;

    size_t size() const { return transmitList.size(); }

    Tick deferredPacketReadyTime() const
    { return transmitList.empty() ? MaxTick : transmitList.front().tick; }

    bool checkConflict(const PacketPtr pkt, const int blk_size) const;

    bool trySatisfyFunctional(PacketPtr pkt);

    void schedSendEvent(Tick when);

    void schedSendTiming(PacketPtr pkt, Tick when);

    void retry();

    void disableSanityCheck() { _disableSanityCheck = true; }

    DrainState drain() override;
};

class ReqPacketQueue : public PacketQueue
{

  protected:

    MasterPort& masterPort;

    // Static definition so it can be called when constructing the parent
    // without us being completely initialized.
    static const std::string name(const MasterPort& masterPort,
                                  const std::string& label)
    { return masterPort.name() + "-" + label; }

  public:

    ReqPacketQueue(EventManager& _em, MasterPort& _masterPort,
                   const std::string _label = "ReqPacketQueue");

    virtual ~ReqPacketQueue() { }

    const std::string name() const
    { return name(masterPort, label); }

    bool sendTiming(PacketPtr pkt);

};

class SnoopRespPacketQueue : public PacketQueue
{

  protected:

    MasterPort& masterPort;

    // Static definition so it can be called when constructing the parent
    // without us being completely initialized.
    static const std::string name(const MasterPort& masterPort,
                                  const std::string& label)
    { return masterPort.name() + "-" + label; }

  public:

    SnoopRespPacketQueue(EventManager& _em, MasterPort& _masterPort,
                         bool force_order = false,
                         const std::string _label = "SnoopRespPacketQueue");

    virtual ~SnoopRespPacketQueue() { }

    const std::string name() const
    { return name(masterPort, label); }

    bool sendTiming(PacketPtr pkt);

};

class RespPacketQueue : public PacketQueue
{

  protected:

    SlavePort& slavePort;

    // Static definition so it can be called when constructing the parent
    // without us being completely initialized.
    static const std::string name(const SlavePort& slavePort,
                                  const std::string& label)
    { return slavePort.name() + "-" + label; }

  public:

    RespPacketQueue(EventManager& _em, SlavePort& _slavePort,
                    bool force_order = false,
                    const std::string _label = "RespPacketQueue");

    virtual ~RespPacketQueue() { }

    const std::string name() const
    { return name(slavePort, label); }

    bool sendTiming(PacketPtr pkt);

};

#endif // __MEM_PACKET_QUEUE_HH__