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Diffstat (limited to 'src/mem/tport.cc')
-rw-r--r-- | src/mem/tport.cc | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/src/mem/tport.cc b/src/mem/tport.cc new file mode 100644 index 000000000..55c301c87 --- /dev/null +++ b/src/mem/tport.cc @@ -0,0 +1,97 @@ +/* + * Copyright (c) 2006 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: Ali Saidi + */ + +#include "mem/tport.hh" + +void +SimpleTimingPort::recvFunctional(Packet *pkt) +{ + // just do an atomic access and throw away the returned latency + recvAtomic(pkt); +} + +bool +SimpleTimingPort::recvTiming(Packet *pkt) +{ + // If the device is only a slave, it should only be sending + // responses, which should never get nacked. There used to be + // code to hanldle nacks here, but I'm pretty sure it didn't work + // correctly with the drain code, so that would need to be fixed + // if we ever added it back. + assert(pkt->result != Packet::Nacked); + Tick latency = recvAtomic(pkt); + // turn packet around to go back to requester + pkt->makeTimingResponse(); + sendTimingLater(pkt, latency); + return true; +} + +void +SimpleTimingPort::recvRetry() +{ + bool result = true; + while (result && transmitList.size()) { + result = sendTiming(transmitList.front()); + if (result) + transmitList.pop_front(); + } + if (transmitList.size() == 0 && drainEvent) { + drainEvent->process(); + drainEvent = NULL; + } +} + +void +SimpleTimingPort::SendEvent::process() +{ + port->outTiming--; + assert(port->outTiming >= 0); + if (port->sendTiming(packet)) { + // send successfule + if (port->transmitList.size() == 0 && port->drainEvent) { + port->drainEvent->process(); + port->drainEvent = NULL; + } + } else { + // send unsuccessful (due to flow control). Will get retry + // callback later; save for then. + port->transmitList.push_back(packet); + } +} + + +unsigned int +SimpleTimingPort::drain(Event *de) +{ + if (outTiming == 0 && transmitList.size() == 0) + return 0; + drainEvent = de; + return 1; +} |