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Diffstat (limited to 'src/mem/protocol/timing.hh')
| -rw-r--r-- | src/mem/protocol/timing.hh | 190 |
1 files changed, 190 insertions, 0 deletions
diff --git a/src/mem/protocol/timing.hh b/src/mem/protocol/timing.hh new file mode 100644 index 000000000..108ac9796 --- /dev/null +++ b/src/mem/protocol/timing.hh @@ -0,0 +1,190 @@ +/* + * Copyright (c) 2011-2012,2015,2017 ARM Limited + * All rights reserved + * + * 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 + * 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 + * contributors may be used to endorse or promote products derived from + * this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * Authors: Ron Dreslinski + * Andreas Hansson + * William Wang + */ + +#ifndef __MEM_GEM5_PROTOCOL_TIMING_HH__ +#define __MEM_GEM5_PROTOCOL_TIMING_HH__ + +#include "mem/packet.hh" + +class TimingResponseProtocol; + +class TimingRequestProtocol +{ + friend class TimingResponseProtocol; + + protected: + /** + * Attempt to send a timing request to the peer by calling + * its corresponding receive function. If the send does not + * succeed, as indicated by the return value, then the sender must + * wait for a recvReqRetry at which point it can re-issue a + * sendTimingReq. + * + * @param peer Peer to send packet to. + * @param pkt Packet to send. + * + * @return If the send was succesful or not. + */ + bool sendReq(TimingResponseProtocol *peer, PacketPtr pkt); + + /** + * Check if the peer can handle a timing request. + * + * If the send cannot be handled at the moment, as indicated by + * the return value, then the sender will receive a recvReqRetry + * at which point it can re-issue a sendTimingReq. + * + * @param peer Peer to send packet to. + * @param pkt Packet to send. + * + * @return If the send was succesful or not. + */ + bool trySend(TimingResponseProtocol *peer, PacketPtr pkt) const; + + /** + * Attempt to send a timing snoop response packet to it's peer + * by calling its corresponding receive function. If the send + * does not succeed, as indicated by the return value, then the + * sender must wait for a recvRetrySnoop at which point it can + * re-issue a sendTimingSnoopResp. + * + * @param pkt Packet to send. + */ + bool sendSnoopResp(TimingResponseProtocol *peer, PacketPtr pkt); + + /** + * Send a retry to the peer that previously attempted a + * sendTimingResp to this protocol and failed. + */ + void sendRetryResp(TimingResponseProtocol *peer); + + /** + * Receive a timing response from the peer. + */ + virtual bool recvTimingResp(PacketPtr pkt) = 0; + + /** + * Receive a timing snoop request from the peer. + */ + virtual void recvTimingSnoopReq(PacketPtr pkt) = 0; + + /** + * Called by the peer if sendTimingReq was called on this peer (causing + * recvTimingReq to be called on the peer) and was unsuccessful. + */ + virtual void recvReqRetry() = 0; + + /** + * Called by the peer if sendTimingSnoopResp was called on this + * protocol (causing recvTimingSnoopResp to be called on the peer) + * and was unsuccessful. + */ + virtual void recvRetrySnoopResp() = 0; +}; + +class TimingResponseProtocol +{ + friend class TimingRequestProtocol; + + protected: + /** + * Attempt to send a timing response to the peer by calling + * its corresponding receive function. If the send does not + * succeed, as indicated by the return value, then the sender must + * wait for a recvRespRetry at which point it can re-issue a + * sendTimingResp. + * + * @param peer Peer to send the packet to. + * @param pkt Packet to send. + * + * @return If the send was succesful or not. + */ + bool sendResp(TimingRequestProtocol *peer, PacketPtr pkt); + + /** + * Attempt to send a timing snoop request packet to the peer + * by calling its corresponding receive function. Snoop requests + * always succeed and hence no return value is needed. + * + * @param peer Peer to send the packet to. + * @param pkt Packet to send. + */ + void sendSnoopReq(TimingRequestProtocol *peer, PacketPtr pkt); + + /** + * Send a retry to the peer that previously attempted a + * sendTimingReq to this protocol and failed. + */ + void sendRetryReq(TimingRequestProtocol *peer); + + /** + * Send a retry to the peer that previously attempted a + * sendTimingSnoopResp to this peer and failed. + */ + void sendRetrySnoopResp(TimingRequestProtocol *peer); + + /** + * Receive a timing request from the peer. + */ + virtual bool recvTimingReq(PacketPtr pkt) = 0; + + /** + * Availability request from the peer. + */ + virtual bool tryTiming(PacketPtr pkt) = 0; + + /** + * Receive a timing snoop response from the peer. + */ + virtual bool recvTimingSnoopResp(PacketPtr pkt) = 0; + + /** + * Called by the peer if sendTimingResp was called on this + * protocol (causing recvTimingResp to be called on the peer) + * and was unsuccessful. + */ + virtual void recvRespRetry() = 0; +}; + +#endif //__MEM_GEM5_PROTOCOL_TIMING_HH__ |