/*
+ * 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.
*
* 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"
+#include "sim/sim_object.hh"
-bool
-SimpleTimingPort::checkFunctional(PacketPtr pkt)
+SimpleTimingPort::SimpleTimingPort(const std::string& _name,
+ SimObject* _owner) :
+ QueuedResponsePort(_name, _owner, queueImpl), queueImpl(*_owner, *this)
{
- 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(PacketPtr pkt)
{
- if (!checkFunctional(pkt)) {
- // Just do an atomic access and throw away the returned latency
+ 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->isRequest());
-
- if (pkt->memInhibitAsserted()) {
- // snooper will supply based on copy of packet
- // still target's responsibility to delete packet
- delete pkt;
- return true;
- }
+ // 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
+ // turn packet around to go back to requestor if response expected
if (needsResponse) {
// recvAtomic() should already have turned packet into
// atomic response
assert(pkt->isResponse());
- schedSendTiming(pkt, curTick + latency);
+ schedTimingResp(pkt, curTick() + latency);
} else {
- delete pkt;
+ // queue the packet for deletion
+ pendingDelete.reset(pkt);
}
return true;
}
-
-
-void
-SimpleTimingPort::schedSendTiming(PacketPtr pkt, Tick when)
-{
- 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;
- }
-
- // 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::sendDeferredPacket()
-{
- 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 (transmitList.empty() && drainEvent) {
- drainEvent->process();
- drainEvent = NULL;
- }
- } else {
- // 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 (transmitList.size() == 0)
- return 0;
- drainEvent = de;
- return 1;
-}
projects / gem5.git / blobdiff