packet_queue.hh

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/*
 * Copyright (c) 2012,2015,2018 ARM Limited
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 *
 * The license below extends only to copyright in the software and shall
 * not be construed as granting a license to any other intellectual
 * property including but not limited to intellectual property relating
 * to a hardware implementation of the functionality of the software
 * licensed hereunder.  You may use the software subject to the license
 * 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.
 *
 * Copyright (c) 2006 The Regents of The University of Michigan
 * All rights reserved.
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 * 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
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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"
 
namespace gem5
{
 
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:
 
    RequestPort& memSidePort;
 
    // Static definition so it can be called when constructing the parent
    // without us being completely initialized.
    static const std::string name(const RequestPort& memSidePort,
                                  const std::string& label)
    { return memSidePort.name() + "-" + label; }
 
  public:
 
    ReqPacketQueue(EventManager& _em, RequestPort& _mem_side_port,
                   const std::string _label = "ReqPacketQueue");
 
    virtual ~ReqPacketQueue() { }
 
    const std::string name() const
    { return name(memSidePort, label); }
 
    bool sendTiming(PacketPtr pkt);
 
};
 
class SnoopRespPacketQueue : public PacketQueue
{
 
  protected:
 
    RequestPort& memSidePort;
 
    // Static definition so it can be called when constructing the parent
    // without us being completely initialized.
    static const std::string name(const RequestPort& memSidePort,
                                  const std::string& label)
    { return memSidePort.name() + "-" + label; }
 
  public:
 
    SnoopRespPacketQueue(EventManager& _em, RequestPort& _mem_side_port,
                         bool force_order = false,
                         const std::string _label = "SnoopRespPacketQueue");
 
    virtual ~SnoopRespPacketQueue() { }
 
    const std::string name() const
    { return name(memSidePort, label); }
 
    bool sendTiming(PacketPtr pkt);
 
};
 
class RespPacketQueue : public PacketQueue
{
 
  protected:
 
    ResponsePort& cpuSidePort;
 
    // Static definition so it can be called when constructing the parent
    // without us being completely initialized.
    static const std::string name(const ResponsePort& cpuSidePort,
                                  const std::string& label)
    { return cpuSidePort.name() + "-" + label; }
 
  public:
 
    RespPacketQueue(EventManager& _em, ResponsePort& _cpu_side_port,
                    bool force_order = false,
                    const std::string _label = "RespPacketQueue");
 
    virtual ~RespPacketQueue() { }
 
    const std::string name() const
    { return name(cpuSidePort, label); }
 
    bool sendTiming(PacketPtr pkt);
 
};
 
} // namespace gem5
 
#endif // __MEM_PACKET_QUEUE_HH__