/*
- * Copyright (c) 2011-2013 ARM Limited
+ * Copyright (c) 2011-2013, 2015 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
* and a slave through a request and response queue.
*/
+#include "mem/bridge.hh"
+
#include "base/trace.hh"
#include "debug/Bridge.hh"
-#include "mem/bridge.hh"
#include "params/Bridge.hh"
Bridge::BridgeSlavePort::BridgeSlavePort(const std::string& _name,
std::vector<AddrRange> _ranges)
: SlavePort(_name, &_bridge), bridge(_bridge), masterPort(_masterPort),
delay(_delay), ranges(_ranges.begin(), _ranges.end()),
- outstandingResponses(0), retryReq(false),
- respQueueLimit(_resp_limit), sendEvent(*this)
+ outstandingResponses(0), retryReq(false), respQueueLimit(_resp_limit),
+ sendEvent([this]{ trySendTiming(); }, _name)
{
}
BridgeSlavePort& _slavePort,
Cycles _delay, int _req_limit)
: MasterPort(_name, &_bridge), bridge(_bridge), slavePort(_slavePort),
- delay(_delay), reqQueueLimit(_req_limit), sendEvent(*this)
+ delay(_delay), reqQueueLimit(_req_limit),
+ sendEvent([this]{ trySendTiming(); }, _name)
{
}
Bridge::Bridge(Params *p)
- : MemObject(p),
+ : ClockedObject(p),
slavePort(p->name + ".slave", *this, masterPort,
ticksToCycles(p->delay), p->resp_size, p->ranges),
masterPort(p->name + ".master", *this, slavePort,
{
}
-BaseMasterPort&
-Bridge::getMasterPort(const std::string &if_name, PortID idx)
+Port &
+Bridge::getPort(const std::string &if_name, PortID idx)
{
if (if_name == "master")
return masterPort;
- else
- // pass it along to our super class
- return MemObject::getMasterPort(if_name, idx);
-}
-
-BaseSlavePort&
-Bridge::getSlavePort(const std::string &if_name, PortID idx)
-{
- if (if_name == "slave")
+ else if (if_name == "slave")
return slavePort;
else
// pass it along to our super class
- return MemObject::getSlavePort(if_name, idx);
+ return ClockedObject::getPort(if_name, idx);
}
void
DPRINTF(Bridge, "Request queue size: %d\n", transmitList.size());
- // @todo: We need to pay for this and not just zero it out
- pkt->firstWordDelay = pkt->lastWordDelay = 0;
+ // technically the packet only reaches us after the header delay,
+ // and typically we also need to deserialise any payload (unless
+ // the two sides of the bridge are synchronous)
+ Tick receive_delay = pkt->headerDelay + pkt->payloadDelay;
+ pkt->headerDelay = pkt->payloadDelay = 0;
- slavePort.schedTimingResp(pkt, bridge.clockEdge(delay));
+ slavePort.schedTimingResp(pkt, bridge.clockEdge(delay) +
+ receive_delay);
return true;
}
DPRINTF(Bridge, "recvTimingReq: %s addr 0x%x\n",
pkt->cmdString(), pkt->getAddr());
- // we should not see a timing request if we are already in a retry
- assert(!retryReq);
+ panic_if(pkt->cacheResponding(), "Should not see packets where cache "
+ "is responding");
+
+ // we should not get a new request after committing to retry the
+ // current one, but unfortunately the CPU violates this rule, so
+ // simply ignore it for now
+ if (retryReq)
+ return false;
DPRINTF(Bridge, "Response queue size: %d outresp: %d\n",
transmitList.size(), outstandingResponses);
retryReq = true;
} else {
// look at the response queue if we expect to see a response
- bool expects_response = pkt->needsResponse() &&
- !pkt->memInhibitAsserted();
+ bool expects_response = pkt->needsResponse();
if (expects_response) {
if (respQueueFull()) {
DPRINTF(Bridge, "Response queue full\n");
}
if (!retryReq) {
- // @todo: We need to pay for this and not just zero it out
- pkt->firstWordDelay = pkt->lastWordDelay = 0;
-
- masterPort.schedTimingReq(pkt, bridge.clockEdge(delay));
+ // technically the packet only reaches us after the header
+ // delay, and typically we also need to deserialise any
+ // payload (unless the two sides of the bridge are
+ // synchronous)
+ Tick receive_delay = pkt->headerDelay + pkt->payloadDelay;
+ pkt->headerDelay = pkt->payloadDelay = 0;
+
+ masterPort.schedTimingReq(pkt, bridge.clockEdge(delay) +
+ receive_delay);
}
}
if (retryReq) {
DPRINTF(Bridge, "Request waiting for retry, now retrying\n");
retryReq = false;
- sendRetry();
+ sendRetryReq();
}
}
void
Bridge::BridgeMasterPort::schedTimingReq(PacketPtr pkt, Tick when)
{
- // If we expect to see a response, we need to restore the source
- // and destination field that is potentially changed by a second
- // crossbar
- if (!pkt->memInhibitAsserted() && pkt->needsResponse()) {
- // Update the sender state so we can deal with the response
- // appropriately
- pkt->pushSenderState(new RequestState(pkt->getSrc()));
- }
-
// If we're about to put this packet at the head of the queue, we
// need to schedule an event to do the transmit. Otherwise there
// should already be an event scheduled for sending the head
assert(transmitList.size() != reqQueueLimit);
- transmitList.push_back(DeferredPacket(pkt, when));
+ transmitList.emplace_back(pkt, when);
}
void
Bridge::BridgeSlavePort::schedTimingResp(PacketPtr pkt, Tick when)
{
- // This is a response for a request we forwarded earlier. The
- // corresponding request state should be stored in the packet's
- // senderState field.
- RequestState *req_state =
- dynamic_cast<RequestState*>(pkt->popSenderState());
- assert(req_state != NULL);
- pkt->setDest(req_state->origSrc);
- delete req_state;
-
- // the bridge sets the destination irrespective of it is valid or
- // not, as it is checked in the crossbar
- DPRINTF(Bridge, "response, new dest %d\n", pkt->getDest());
-
// If we're about to put this packet at the head of the queue, we
// need to schedule an event to do the transmit. Otherwise there
// should already be an event scheduled for sending the head
bridge.schedule(sendEvent, when);
}
- transmitList.push_back(DeferredPacket(pkt, when));
+ transmitList.emplace_back(pkt, when);
}
void
if (!masterPort.reqQueueFull() && retryReq) {
DPRINTF(Bridge, "Request waiting for retry, now retrying\n");
retryReq = false;
- sendRetry();
+ sendRetryReq();
}
}
}
void
-Bridge::BridgeMasterPort::recvRetry()
+Bridge::BridgeMasterPort::recvReqRetry()
{
trySendTiming();
}
void
-Bridge::BridgeSlavePort::recvRetry()
+Bridge::BridgeSlavePort::recvRespRetry()
{
trySendTiming();
}
Tick
Bridge::BridgeSlavePort::recvAtomic(PacketPtr pkt)
{
+ panic_if(pkt->cacheResponding(), "Should not see packets where cache "
+ "is responding");
+
return delay * bridge.clockPeriod() + masterPort.sendAtomic(pkt);
}
// check the response queue
for (auto i = transmitList.begin(); i != transmitList.end(); ++i) {
- if (pkt->checkFunctional((*i).pkt)) {
+ if (pkt->trySatisfyFunctional((*i).pkt)) {
pkt->makeResponse();
return;
}
}
// also check the master port's request queue
- if (masterPort.checkFunctional(pkt)) {
+ if (masterPort.trySatisfyFunctional(pkt)) {
return;
}
}
bool
-Bridge::BridgeMasterPort::checkFunctional(PacketPtr pkt)
+Bridge::BridgeMasterPort::trySatisfyFunctional(PacketPtr pkt)
{
bool found = false;
auto i = transmitList.begin();
- while(i != transmitList.end() && !found) {
- if (pkt->checkFunctional((*i).pkt)) {
+ while (i != transmitList.end() && !found) {
+ if (pkt->trySatisfyFunctional((*i).pkt)) {
pkt->makeResponse();
found = true;
}
projects / gem5.git / blobdiff