src/mem/protocol/functional.hh

/*
 * Copyright (c) 2011-2012,2015,2017 ARM Limited
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 *
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 * 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
 * unmodified and in its entirety in all distributions of the software,
 * modified or unmodified, in source code or in binary form.
 *
 * Copyright (c) 2002-2005 The Regents of The University of Michigan
 * 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
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 * this software without specific prior written permission.
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#ifndef __MEM_GEM5_PROTOCOL_FUNCTIONAL_HH__
#define __MEM_GEM5_PROTOCOL_FUNCTIONAL_HH__

#include "mem/backdoor.hh"
#include "mem/packet.hh"

namespace gem5
{

class FunctionalResponseProtocol;

class FunctionalRequestProtocol
{
    friend class FunctionalResponseProtocol;

  protected:
    /**
     * Send a functional request packet, where the data is instantly
     * updated everywhere in the memory system, without affecting the
     * current state of any block or moving the block.
     *
     * @param pkt Packet to send.
     */
    void send(FunctionalResponseProtocol *peer, PacketPtr pkt) const;

    /**
     * Receive a functional snoop request packet from the peer.
     */
    virtual void recvFunctionalSnoop(PacketPtr pkt) = 0;

    /**
     * Send a request for a back door to a range of memory.
     *
     * @param req An object which describes what back door is being requested.
     * @param backdoor Can be set to a back door pointer by the target to let
     *        caller have direct access to the requested range.
     */
    void sendMemBackdoorReq(FunctionalResponseProtocol *peer,
            const MemBackdoorReq &req, MemBackdoorPtr &backdoor);
};

class FunctionalResponseProtocol
{
    friend class FunctionalRequestProtocol;

  protected:
    /**
     * Send a functional snoop request packet, where the data is
     * instantly updated everywhere in the memory system, without
     * affecting the current state of any block or moving the block.
     *
     * @param pkt Snoop packet to send.
     */
    void sendSnoop(FunctionalRequestProtocol *peer, PacketPtr pkt) const;

    /**
     * Receive a functional request packet from the peer.
     */
    virtual void recvFunctional(PacketPtr pkt) = 0;

    /**
     * Receive a request for a back door to a range of memory.
     *
     * @param req An object which describes what back door is being requested.
     * @param backdoor Can be set to a back door pointer by the target to let
     *        caller have direct access to the requested range.
     */
    virtual void recvMemBackdoorReq(const MemBackdoorReq &req,
            MemBackdoorPtr &backdoor) = 0;
};

} // namespace gem5

#endif //__MEM_GEM5_PROTOCOL_FUNCTIONAL_HH__