Files
gem5/src/mem/tport.hh
Ali Saidi 851f91f245 Move PioPort timing code into Simple Timing Port object
Make PioPort use it
Make Physical memory use it as well

src/SConscript:
    Add timing port to sconscript
src/dev/io_device.cc:
src/dev/io_device.hh:
    Move simple timing pio port stuff into a simple timing port class so it can be used by the physical memory
src/mem/physical.cc:
src/mem/physical.hh:
    use a simple timing port stuff instead of rolling our own here

--HG--
extra : convert_revision : e5befbd295a572568cfdca533efb5ed1984c59d1
2006-07-20 19:03:47 -04:00

135 lines
4.4 KiB
C++

/*
* 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
*/
/**
* @file
* Implement a port which adds simple support of a sendTiming() function that
* takes a delay. In this way the * device can immediatly call
* sendTiming(pkt, time) after processing a request and the request will be
* handled by the port even if the port bus the device connects to is blocked.
*/
/** recvTiming and drain should be implemented something like this when this
* class is used.
bool
PioPort::recvTiming(Packet *pkt)
{
if (pkt->result == Packet::Nacked) {
resendNacked(pkt);
} else {
Tick latency = device->recvAtomic(pkt);
// turn packet around to go back to requester
pkt->makeTimingResponse();
sendTiming(pkt, latency);
}
return true;
}
PioDevice::drain(Event *de)
{
unsigned int count;
count = SimpleTimingPort->drain(de);
if (count)
changeState(Draining);
else
changeState(Drained);
return count;
}
*/
#ifndef __MEM_TPORT_HH__
#define __MEM_TPORT_HH__
#include "mem/port.hh"
#include "sim/eventq.hh"
#include <list>
#include <string>
class SimpleTimingPort : public Port
{
protected:
/** A list of outgoing timing response packets that haven't been serviced
* yet. */
std::list<Packet*> transmitList;
/**
* This class is used to implemented sendTiming() with a delay. When a delay
* is requested a new event is created. When the event time expires it
* attempts to send the packet. If it cannot, the packet is pushed onto the
* transmit list to be sent when recvRetry() is called. */
class SendEvent : public Event
{
SimpleTimingPort *port;
Packet *packet;
SendEvent(SimpleTimingPort *p, Packet *pkt, Tick t)
: Event(&mainEventQueue), port(p), packet(pkt)
{ setFlags(AutoDelete); schedule(curTick + t); }
virtual void process();
virtual const char *description()
{ return "Future scheduled sendTiming event"; }
friend class SimpleTimingPort;
};
/** Number of timing requests that are emulating the device timing before
* attempting to end up on the bus.
*/
int outTiming;
/** If we need to drain, keep the drain event around until we're done
* here.*/
Event *drainEvent;
/** Schedule a sendTiming() event to be called in the future. */
void sendTiming(Packet *pkt, Tick time)
{ outTiming++; new SimpleTimingPort::SendEvent(this, pkt, time); }
/** This function is notification that the device should attempt to send a
* packet again. */
virtual void recvRetry();
void resendNacked(Packet *pkt);
public:
SimpleTimingPort(std::string pname)
: Port(pname), outTiming(0), drainEvent(NULL)
{}
unsigned int drain(Event *de);
friend class SimpleTimingPort::SendEvent;
};
#endif // __MEM_TPORT_HH__