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31 #include "mem/tport.hh"
34 SimpleTimingPort::checkFunctional(PacketPtr pkt
)
36 DeferredPacketIterator i
= transmitList
.begin();
37 DeferredPacketIterator end
= transmitList
.end();
39 for (; i
!= end
; ++i
) {
40 PacketPtr target
= i
->pkt
;
41 // If the target contains data, and it overlaps the
42 // probed request, need to update data
43 if (pkt
->checkFunctional(target
)) {
52 SimpleTimingPort::recvFunctional(PacketPtr pkt
)
54 if (!checkFunctional(pkt
)) {
55 // Just do an atomic access and throw away the returned latency
61 SimpleTimingPort::recvTiming(PacketPtr pkt
)
63 // If the device is only a slave, it should only be sending
64 // responses, which should never get nacked. There used to be
65 // code to hanldle nacks here, but I'm pretty sure it didn't work
66 // correctly with the drain code, so that would need to be fixed
67 // if we ever added it back.
68 //assert(pkt->isRequest());
70 if (pkt
->memInhibitAsserted()) {
71 // snooper will supply based on copy of packet
72 // still target's responsibility to delete packet
77 bool needsResponse
= pkt
->needsResponse();
78 Tick latency
= recvAtomic(pkt
);
79 // turn packet around to go back to requester if response expected
81 // recvAtomic() should already have turned packet into
83 assert(pkt
->isResponse());
84 schedSendTiming(pkt
, curTick
+ latency
);
94 SimpleTimingPort::schedSendTiming(PacketPtr pkt
, Tick when
)
96 assert(when
> curTick
);
97 assert(when
< curTick
+ Clock::Int::ms
);
99 // Nothing is on the list: add it and schedule an event
100 if (transmitList
.empty() || when
< transmitList
.front().tick
) {
101 transmitList
.push_front(DeferredPacket(when
, pkt
));
102 schedSendEvent(when
);
106 // list is non-empty & this belongs at the end
107 if (when
>= transmitList
.back().tick
) {
108 transmitList
.push_back(DeferredPacket(when
, pkt
));
112 // this belongs in the middle somewhere
113 DeferredPacketIterator i
= transmitList
.begin();
114 i
++; // already checked for insertion at front
115 DeferredPacketIterator end
= transmitList
.end();
117 for (; i
!= end
; ++i
) {
118 if (when
< i
->tick
) {
119 transmitList
.insert(i
, DeferredPacket(when
, pkt
));
123 assert(false); // should never get here
128 SimpleTimingPort::sendDeferredPacket()
130 assert(deferredPacketReady());
131 // take packet off list here; if recvTiming() on the other side
132 // calls sendTiming() back on us (like SimpleTimingCpu does), then
133 // we get confused by having a non-active packet on transmitList
134 DeferredPacket dp
= transmitList
.front();
135 transmitList
.pop_front();
136 bool success
= sendTiming(dp
.pkt
);
139 if (!transmitList
.empty() && !sendEvent
->scheduled()) {
140 Tick time
= transmitList
.front().tick
;
141 schedule(sendEvent
, time
<= curTick
? curTick
+1 : time
);
144 if (transmitList
.empty() && drainEvent
) {
145 drainEvent
->process();
149 // Unsuccessful, need to put back on transmitList. Callee
150 // should not have messed with it (since it didn't accept that
151 // packet), so we can just push it back on the front.
152 assert(!sendEvent
->scheduled());
153 transmitList
.push_front(dp
);
156 waitingOnRetry
= !success
;
158 if (waitingOnRetry
) {
159 DPRINTF(Bus
, "Send failed, waiting on retry\n");
165 SimpleTimingPort::recvRetry()
167 DPRINTF(Bus
, "Received retry\n");
168 assert(waitingOnRetry
);
169 sendDeferredPacket();
174 SimpleTimingPort::processSendEvent()
176 assert(!waitingOnRetry
);
177 sendDeferredPacket();
182 SimpleTimingPort::drain(Event
*de
)
184 if (transmitList
.size() == 0)