#include "mem/tport.hh"
+bool
+SimpleTimingPort::checkFunctional(PacketPtr pkt)
+{
+ DeferredPacketIterator i = transmitList.begin();
+ DeferredPacketIterator end = transmitList.end();
+
+ for (; i != end; ++i) {
+ PacketPtr target = i->pkt;
+ // If the target contains data, and it overlaps the
+ // probed request, need to update data
+ if (pkt->checkFunctional(target)) {
+ return true;
+ }
+ }
+
+ return false;
+}
+
void
-SimpleTimingPort::recvFunctional(Packet *pkt)
+SimpleTimingPort::recvFunctional(PacketPtr pkt)
{
- // just do an atomic access and throw away the returned latency
- recvAtomic(pkt);
+ if (!checkFunctional(pkt)) {
+ // Just do an atomic access and throw away the returned latency
+ recvAtomic(pkt);
+ }
}
bool
-SimpleTimingPort::recvTiming(Packet *pkt)
+SimpleTimingPort::recvTiming(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);
+
+ if (pkt->memInhibitAsserted()) {
+ // snooper will supply based on copy of packet
+ // still target's responsibility to delete packet
+ delete pkt;
+ return true;
+ }
+
+ bool needsResponse = pkt->needsResponse();
Tick latency = recvAtomic(pkt);
// turn packet around to go back to requester if response expected
- if (pkt->needsResponse()) {
- pkt->makeTimingResponse();
- sendTimingLater(pkt, latency);
+ if (needsResponse) {
+ // recvAtomic() should already have turned packet into
+ // atomic response
+ assert(pkt->isResponse());
+ schedSendTiming(pkt, curTick + latency);
+ } else {
+ delete pkt;
}
+
return true;
}
+
void
-SimpleTimingPort::recvRetry()
+SimpleTimingPort::schedSendTiming(PacketPtr pkt, Tick when)
{
- assert(outTiming > 0);
- assert(!transmitList.empty());
- if (sendTiming(transmitList.front())) {
- transmitList.pop_front();
- outTiming--;
- DPRINTF(Bus, "No Longer waiting on retry\n");
- if (!transmitList.empty())
- sendTimingLater(transmitList.front(), 1);
+ assert(when > curTick);
+ assert(when < curTick + Clock::Int::ms);
+
+ // Nothing is on the list: add it and schedule an event
+ if (transmitList.empty() || when < transmitList.front().tick) {
+ transmitList.push_front(DeferredPacket(when, pkt));
+ schedSendEvent(when);
+ return;
+ }
+
+ // list is non-empty & this belongs at the end
+ if (when >= transmitList.back().tick) {
+ transmitList.push_back(DeferredPacket(when, pkt));
+ return;
}
- if (transmitList.empty() && drainEvent) {
- drainEvent->process();
- drainEvent = NULL;
+ // this belongs in the middle somewhere
+ DeferredPacketIterator i = transmitList.begin();
+ i++; // already checked for insertion at front
+ DeferredPacketIterator end = transmitList.end();
+
+ for (; i != end; ++i) {
+ if (when < i->tick) {
+ transmitList.insert(i, DeferredPacket(when, pkt));
+ return;
+ }
}
+ assert(false); // should never get here
}
+
void
-SimpleTimingPort::SendEvent::process()
+SimpleTimingPort::sendDeferredPacket()
{
- assert(port->outTiming > 0);
- if (!port->transmitList.empty() && port->transmitList.front() != packet) {
- //We are not the head of the list
- port->transmitList.push_back(packet);
- } else if (port->sendTiming(packet)) {
- // send successful
- if (port->transmitList.size()) {
- port->transmitList.pop_front();
- port->outTiming--;
- if (!port->transmitList.empty())
- port->sendTimingLater(port->transmitList.front(), 1);
+ assert(deferredPacketReady());
+ // take packet off list here; if recvTiming() on the other side
+ // calls sendTiming() back on us (like SimpleTimingCpu does), then
+ // we get confused by having a non-active packet on transmitList
+ DeferredPacket dp = transmitList.front();
+ transmitList.pop_front();
+ bool success = sendTiming(dp.pkt);
+
+ if (success) {
+ if (!transmitList.empty() && !sendEvent->scheduled()) {
+ Tick time = transmitList.front().tick;
+ schedule(sendEvent, time <= curTick ? curTick+1 : time);
}
- if (port->transmitList.empty() && port->drainEvent) {
- port->drainEvent->process();
- port->drainEvent = NULL;
+
+ if (transmitList.empty() && drainEvent) {
+ drainEvent->process();
+ drainEvent = NULL;
}
} else {
- // send unsuccessful (due to flow control). Will get retry
- // callback later; save for then if not already
- DPRINTF(Bus, "Waiting on retry\n");
- if (!(port->transmitList.front() == packet))
- port->transmitList.push_back(packet);
+ // Unsuccessful, need to put back on transmitList. Callee
+ // should not have messed with it (since it didn't accept that
+ // packet), so we can just push it back on the front.
+ assert(!sendEvent->scheduled());
+ transmitList.push_front(dp);
}
+
+ waitingOnRetry = !success;
+
+ if (waitingOnRetry) {
+ DPRINTF(Bus, "Send failed, waiting on retry\n");
+ }
+}
+
+
+void
+SimpleTimingPort::recvRetry()
+{
+ DPRINTF(Bus, "Received retry\n");
+ assert(waitingOnRetry);
+ sendDeferredPacket();
+}
+
+
+void
+SimpleTimingPort::processSendEvent()
+{
+ assert(!waitingOnRetry);
+ sendDeferredPacket();
}
unsigned int
SimpleTimingPort::drain(Event *de)
{
- if (outTiming == 0 && transmitList.size() == 0)
+ if (transmitList.size() == 0)
return 0;
drainEvent = de;
return 1;
projects / gem5.git / blobdiff