/*
+ * Copyright (c) 2012 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) 2006 The Regents of The University of Michigan
* All rights reserved.
*
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Ali Saidi
+ * Andreas Hansson
*/
#include "mem/tport.hh"
+#include "sim/sim_object.hh"
-void
-SimpleTimingPort::checkFunctional(PacketPtr pkt)
+SimpleTimingPort::SimpleTimingPort(const std::string& _name,
+ SimObject* _owner) :
+ QueuedSlavePort(_name, _owner, queueImpl), queueImpl(*_owner, *this)
{
- DeferredPacketIterator i = transmitList.begin();
- DeferredPacketIterator end = transmitList.end();
-
- while (i != end) {
- PacketPtr target = i->pkt;
- // If the target contains data, and it overlaps the
- // probed request, need to update data
- if (target->intersect(pkt)) {
- if (!fixPacket(pkt, target)) {
- // fixPacket returns true for continue, false for done
- return;
- }
- }
-
- i++;
- }
}
void
SimpleTimingPort::recvFunctional(PacketPtr pkt)
{
- checkFunctional(pkt);
-
- // Just do an atomic access and throw away the returned latency
- if (pkt->result != Packet::Success)
+ if (!respQueue.trySatisfyFunctional(pkt)) {
+ // do an atomic access and throw away the returned latency
recvAtomic(pkt);
+ }
}
bool
-SimpleTimingPort::recvTiming(PacketPtr pkt)
+SimpleTimingPort::recvTimingReq(PacketPtr 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);
+ // the SimpleTimingPort should not be used anywhere where there is
+ // a need to deal with snoop responses and their flow control
+ // requirements
+ if (pkt->cacheResponding())
+ panic("SimpleTimingPort should never see packets with the "
+ "cacheResponding flag set\n");
+
+ bool needsResponse = pkt->needsResponse();
Tick latency = recvAtomic(pkt);
// turn packet around to go back to requester if response expected
- if (pkt->needsResponse()) {
- pkt->makeTimingResponse();
- sendTiming(pkt, latency);
+ if (needsResponse) {
+ // recvAtomic() should already have turned packet into
+ // atomic response
+ assert(pkt->isResponse());
+ schedTimingResp(pkt, curTick() + latency);
+ } else {
+ // queue the packet for deletion
+ pendingDelete.reset(pkt);
}
- else if (pkt->cmd != MemCmd::UpgradeReq) {
- delete pkt->req;
- delete pkt;
- }
- return true;
-}
-void
-SimpleTimingPort::recvRetry()
-{
- assert(!transmitList.empty());
- if (Port::sendTiming(transmitList.front().pkt)) {
- transmitList.pop_front();
- DPRINTF(Bus, "No Longer waiting on retry\n");
- if (!transmitList.empty()) {
- Tick time = transmitList.front().tick;
- sendEvent->schedule(time <= curTick ? curTick+1 : time);
- }
- }
-
- if (transmitList.empty() && drainEvent) {
- drainEvent->process();
- drainEvent = NULL;
- }
-}
-
-void
-SimpleTimingPort::sendTiming(PacketPtr pkt, Tick time)
-{
- // Nothing is on the list: add it and schedule an event
- if (transmitList.empty()) {
- assert(!sendEvent->scheduled());
- sendEvent->schedule(curTick+time);
- transmitList.push_back(DeferredPacket(time+curTick, pkt));
- return;
- }
-
- // something is on the list and this belongs at the end
- if (time+curTick >= transmitList.back().tick) {
- transmitList.push_back(DeferredPacket(time+curTick, pkt));
- return;
- }
- // Something is on the list and this belongs somewhere else
- DeferredPacketIterator i = transmitList.begin();
- DeferredPacketIterator end = transmitList.end();
- bool done = false;
-
- while (i != end && !done) {
- if (time+curTick < i->tick) {
- if (i == transmitList.begin()) {
- //Inserting at begining, reschedule
- sendEvent->reschedule(time+curTick);
- }
- transmitList.insert(i, DeferredPacket(time+curTick, pkt));
- done = true;
- }
- i++;
- }
- assert(done);
-}
-
-void
-SimpleTimingPort::processSendEvent()
-{
- assert(transmitList.size());
- assert(transmitList.front().tick <= curTick);
- if (Port::sendTiming(transmitList.front().pkt)) {
- //send successful, remove packet
- transmitList.pop_front();
- if (!transmitList.empty()) {
- Tick time = transmitList.front().tick;
- sendEvent->schedule(time <= curTick ? curTick+1 : time);
- }
- if (transmitList.empty() && drainEvent) {
- drainEvent->process();
- drainEvent = NULL;
- }
- return;
- }
- // send unsuccessful (due to flow control). Will get retry
- // callback later; save for then if not already
- DPRINTF(Bus, "Waiting on retry\n");
-}
-
-
-unsigned int
-SimpleTimingPort::drain(Event *de)
-{
- if (transmitList.size() == 0)
- return 0;
- drainEvent = de;
- return 1;
+ return true;
}
projects / gem5.git / blobdiff