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31 #include "debug/Bus.hh"
32 #include "mem/tport.hh"
36 SimpleTimingPort::SimpleTimingPort(string pname
, MemObject
*_owner
)
37 : Port(pname
, _owner
), sendEvent(0), drainEvent(NULL
),
40 sendEvent
= new EventWrapper
<SimpleTimingPort
,
41 &SimpleTimingPort::processSendEvent
>(this);
44 SimpleTimingPort::~SimpleTimingPort()
50 SimpleTimingPort::checkFunctional(PacketPtr pkt
)
52 DeferredPacketIterator i
= transmitList
.begin();
53 DeferredPacketIterator end
= transmitList
.end();
55 for (; i
!= end
; ++i
) {
56 PacketPtr target
= i
->pkt
;
57 // If the target contains data, and it overlaps the
58 // probed request, need to update data
59 if (pkt
->checkFunctional(target
)) {
68 SimpleTimingPort::recvFunctional(PacketPtr pkt
)
70 if (!checkFunctional(pkt
)) {
71 // Just do an atomic access and throw away the returned latency
77 SimpleTimingPort::recvTiming(PacketPtr pkt
)
79 // If the device is only a slave, it should only be sending
80 // responses, which should never get nacked. There used to be
81 // code to hanldle nacks here, but I'm pretty sure it didn't work
82 // correctly with the drain code, so that would need to be fixed
83 // if we ever added it back.
85 if (pkt
->memInhibitAsserted()) {
86 // snooper will supply based on copy of packet
87 // still target's responsibility to delete packet
92 bool needsResponse
= pkt
->needsResponse();
93 Tick latency
= recvAtomic(pkt
);
94 // turn packet around to go back to requester if response expected
96 // recvAtomic() should already have turned packet into
98 assert(pkt
->isResponse());
99 schedSendTiming(pkt
, curTick() + latency
);
109 SimpleTimingPort::schedSendTiming(PacketPtr pkt
, Tick when
)
111 assert(when
> curTick());
112 assert(when
< curTick() + SimClock::Int::ms
);
114 // Nothing is on the list: add it and schedule an event
115 if (transmitList
.empty() || when
< transmitList
.front().tick
) {
116 transmitList
.push_front(DeferredPacket(when
, pkt
));
117 schedSendEvent(when
);
121 // list is non-empty & this belongs at the end
122 if (when
>= transmitList
.back().tick
) {
123 transmitList
.push_back(DeferredPacket(when
, pkt
));
127 // this belongs in the middle somewhere
128 DeferredPacketIterator i
= transmitList
.begin();
129 i
++; // already checked for insertion at front
130 DeferredPacketIterator end
= transmitList
.end();
132 for (; i
!= end
; ++i
) {
133 if (when
< i
->tick
) {
134 transmitList
.insert(i
, DeferredPacket(when
, pkt
));
138 assert(false); // should never get here
143 SimpleTimingPort::sendDeferredPacket()
145 assert(deferredPacketReady());
146 // take packet off list here; if recvTiming() on the other side
147 // calls sendTiming() back on us (like SimpleTimingCpu does), then
148 // we get confused by having a non-active packet on transmitList
149 DeferredPacket dp
= transmitList
.front();
150 transmitList
.pop_front();
151 bool success
= sendTiming(dp
.pkt
);
154 if (!transmitList
.empty() && !sendEvent
->scheduled()) {
155 Tick time
= transmitList
.front().tick
;
156 schedule(sendEvent
, time
<= curTick() ? curTick()+1 : time
);
159 if (transmitList
.empty() && drainEvent
&& !sendEvent
->scheduled()) {
160 drainEvent
->process();
164 // Unsuccessful, need to put back on transmitList. Callee
165 // should not have messed with it (since it didn't accept that
166 // packet), so we can just push it back on the front.
167 assert(!sendEvent
->scheduled());
168 transmitList
.push_front(dp
);
171 waitingOnRetry
= !success
;
173 if (waitingOnRetry
) {
174 DPRINTF(Bus
, "Send failed, waiting on retry\n");
180 SimpleTimingPort::recvRetry()
182 DPRINTF(Bus
, "Received retry\n");
183 assert(waitingOnRetry
);
184 sendDeferredPacket();
189 SimpleTimingPort::processSendEvent()
191 assert(!waitingOnRetry
);
192 sendDeferredPacket();
197 SimpleTimingPort::drain(Event
*de
)
199 if (transmitList
.size() == 0 && !sendEvent
->scheduled())