Adding gem5 source to svn.

git-svn-id: https://www4.informatik.uni-erlangen.de/i4svn/danceos/trunk/devel/fail@1819 8c4709b5-6ec9-48aa-a5cd-a96041d1645a
2012-10-24 19:18:57 +00:00
parent f7ff71bd46
commit b41eec3f65
3222 changed files with 658579 additions and 1 deletions
--- a/simulators/gem5/src/mem/bridge.cc
+++ b/simulators/gem5/src/mem/bridge.cc
@ -0,0 +1,455 @@
+/*
+ * Copyright (c) 2011-2012 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.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met: redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer;
+ * redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution;
+ * neither the name of the copyright holders nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * 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
+ *          Steve Reinhardt
+ *          Andreas Hansson
+ */
+
+/**
+ * @file
+ * Implementation of a memory-mapped bus bridge that connects a master
+ * and a slave through a request and response queue.
+ */
+
+#include "base/trace.hh"
+#include "debug/BusBridge.hh"
+#include "mem/bridge.hh"
+#include "params/Bridge.hh"
+
+Bridge::BridgeSlavePort::BridgeSlavePort(const std::string &_name,
+                                         Bridge* _bridge,
+                                         BridgeMasterPort& _masterPort,
+                                         int _delay, int _nack_delay,
+                                         int _resp_limit,
+                                         std::vector<Range<Addr> > _ranges)
+    : SlavePort(_name, _bridge), bridge(_bridge), masterPort(_masterPort),
+      delay(_delay), nackDelay(_nack_delay),
+      ranges(_ranges.begin(), _ranges.end()),
+      outstandingResponses(0), inRetry(false),
+      respQueueLimit(_resp_limit), sendEvent(*this)
+{
+}
+
+Bridge::BridgeMasterPort::BridgeMasterPort(const std::string &_name,
+                                           Bridge* _bridge,
+                                           BridgeSlavePort& _slavePort,
+                                           int _delay, int _req_limit)
+    : MasterPort(_name, _bridge), bridge(_bridge), slavePort(_slavePort),
+      delay(_delay), inRetry(false), reqQueueLimit(_req_limit),
+      sendEvent(*this)
+{
+}
+
+Bridge::Bridge(Params *p)
+    : MemObject(p),
+      slavePort(p->name + "-slave", this, masterPort, p->delay,
+                p->nack_delay, p->resp_size, p->ranges),
+      masterPort(p->name + "-master", this, slavePort, p->delay, p->req_size),
+      ackWrites(p->write_ack), _params(p)
+{
+    if (ackWrites)
+        panic("No support for acknowledging writes\n");
+}
+
+MasterPort&
+Bridge::getMasterPort(const std::string &if_name, int idx)
+{
+    if (if_name == "master")
+        return masterPort;
+    else
+        // pass it along to our super class
+        return MemObject::getMasterPort(if_name, idx);
+}
+
+SlavePort&
+Bridge::getSlavePort(const std::string &if_name, int idx)
+{
+    if (if_name == "slave")
+        return slavePort;
+    else
+        // pass it along to our super class
+        return MemObject::getSlavePort(if_name, idx);
+}
+
+void
+Bridge::init()
+{
+    // make sure both sides are connected and have the same block size
+    if (!slavePort.isConnected() || !masterPort.isConnected())
+        fatal("Both ports of bus bridge are not connected to a bus.\n");
+
+    if (slavePort.peerBlockSize() != masterPort.peerBlockSize())
+        fatal("Slave port size %d, master port size %d \n " \
+              "Busses don't have the same block size... Not supported.\n",
+              slavePort.peerBlockSize(), masterPort.peerBlockSize());
+
+    // notify the master side  of our address ranges
+    slavePort.sendRangeChange();
+}
+
+bool
+Bridge::BridgeSlavePort::respQueueFull()
+{
+    return outstandingResponses == respQueueLimit;
+}
+
+bool
+Bridge::BridgeMasterPort::reqQueueFull()
+{
+    return requestQueue.size() == reqQueueLimit;
+}
+
+bool
+Bridge::BridgeMasterPort::recvTimingResp(PacketPtr pkt)
+{
+    // all checks are done when the request is accepted on the slave
+    // side, so we are guaranteed to have space for the response
+    DPRINTF(BusBridge, "recvTiming: response %s addr 0x%x\n",
+            pkt->cmdString(), pkt->getAddr());
+
+    DPRINTF(BusBridge, "Request queue size: %d\n", requestQueue.size());
+
+    slavePort.queueForSendTiming(pkt);
+
+    return true;
+}
+
+bool
+Bridge::BridgeSlavePort::recvTimingReq(PacketPtr pkt)
+{
+    DPRINTF(BusBridge, "recvTiming: request %s addr 0x%x\n",
+            pkt->cmdString(), pkt->getAddr());
+
+    DPRINTF(BusBridge, "Response queue size: %d outresp: %d\n",
+            responseQueue.size(), outstandingResponses);
+
+    if (masterPort.reqQueueFull()) {
+        DPRINTF(BusBridge, "Request queue full, nacking\n");
+        nackRequest(pkt);
+        return true;
+    }
+
+    if (pkt->needsResponse()) {
+        if (respQueueFull()) {
+            DPRINTF(BusBridge,
+                    "Response queue full, no space for response, nacking\n");
+            DPRINTF(BusBridge,
+                    "queue size: %d outstanding resp: %d\n",
+                    responseQueue.size(), outstandingResponses);
+            nackRequest(pkt);
+            return true;
+        } else {
+            DPRINTF(BusBridge, "Request Needs response, reserving space\n");
+            assert(outstandingResponses != respQueueLimit);
+            ++outstandingResponses;
+        }
+    }
+
+    masterPort.queueForSendTiming(pkt);
+
+    return true;
+}
+
+void
+Bridge::BridgeSlavePort::nackRequest(PacketPtr pkt)
+{
+    // Nack the packet
+    pkt->makeTimingResponse();
+    pkt->setNacked();
+
+    // The Nack packets are stored in the response queue just like any
+    // other response, but they do not occupy any space as this is
+    // tracked by the outstandingResponses, this guarantees space for
+    // the Nack packets, but implicitly means we have an (unrealistic)
+    // unbounded Nack queue.
+
+    // put it on the list to send
+    Tick readyTime = curTick() + nackDelay;
+    DeferredResponse resp(pkt, readyTime, true);
+
+    // nothing on the list, add it and we're done
+    if (responseQueue.empty()) {
+        assert(!sendEvent.scheduled());
+        bridge->schedule(sendEvent, readyTime);
+        responseQueue.push_back(resp);
+        return;
+    }
+
+    assert(sendEvent.scheduled() || inRetry);
+
+    // does it go at the end?
+    if (readyTime >= responseQueue.back().ready) {
+        responseQueue.push_back(resp);
+        return;
+    }
+
+    // ok, somewhere in the middle, fun
+    std::list<DeferredResponse>::iterator i = responseQueue.begin();
+    std::list<DeferredResponse>::iterator end = responseQueue.end();
+    std::list<DeferredResponse>::iterator begin = responseQueue.begin();
+    bool done = false;
+
+    while (i != end && !done) {
+        if (readyTime < (*i).ready) {
+            if (i == begin)
+                bridge->reschedule(sendEvent, readyTime);
+            responseQueue.insert(i, resp);
+            done = true;
+        }
+        i++;
+    }
+    assert(done);
+}
+
+void
+Bridge::BridgeMasterPort::queueForSendTiming(PacketPtr pkt)
+{
+    Tick readyTime = curTick() + delay;
+
+    // If we expect to see a response, we need to restore the source
+    // and destination field that is potentially changed by a second
+    // bus
+    if (!pkt->memInhibitAsserted() && pkt->needsResponse()) {
+        // Update the sender state so we can deal with the response
+        // appropriately
+        RequestState *req_state = new RequestState(pkt);
+        pkt->senderState = req_state;
+    }
+
+    // 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
+    // packet.
+    if (requestQueue.empty()) {
+        bridge->schedule(sendEvent, readyTime);
+    }
+
+    assert(requestQueue.size() != reqQueueLimit);
+
+    requestQueue.push_back(DeferredRequest(pkt, readyTime));
+}
+
+
+void
+Bridge::BridgeSlavePort::queueForSendTiming(PacketPtr pkt)
+{
+    // 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->senderState);
+    assert(req_state != NULL);
+    // set up new packet dest & senderState based on values saved
+    // from original request
+    req_state->fixResponse(pkt);
+
+    // the bridge assumes that at least one bus has set the
+    // destination field of the packet
+    assert(pkt->isDestValid());
+    DPRINTF(BusBridge, "response, new dest %d\n", pkt->getDest());
+    delete req_state;
+
+    Tick readyTime = curTick() + delay;
+
+    // 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
+    // packet.
+    if (responseQueue.empty()) {
+        bridge->schedule(sendEvent, readyTime);
+    }
+    responseQueue.push_back(DeferredResponse(pkt, readyTime));
+}
+
+void
+Bridge::BridgeMasterPort::trySend()
+{
+    assert(!requestQueue.empty());
+
+    DeferredRequest req = requestQueue.front();
+
+    assert(req.ready <= curTick());
+
+    PacketPtr pkt = req.pkt;
+
+    DPRINTF(BusBridge, "trySend request: addr 0x%x\n", pkt->getAddr());
+
+    if (sendTimingReq(pkt)) {
+        // send successful
+        requestQueue.pop_front();
+
+        // If there are more packets to send, schedule event to try again.
+        if (!requestQueue.empty()) {
+            req = requestQueue.front();
+            DPRINTF(BusBridge, "Scheduling next send\n");
+            bridge->schedule(sendEvent,
+                             std::max(req.ready, curTick() + 1));
+        }
+    } else {
+        inRetry = true;
+    }
+
+    DPRINTF(BusBridge, "trySend: request queue size: %d\n",
+            requestQueue.size());
+}
+
+void
+Bridge::BridgeSlavePort::trySend()
+{
+    assert(!responseQueue.empty());
+
+    DeferredResponse resp = responseQueue.front();
+
+    assert(resp.ready <= curTick());
+
+    PacketPtr pkt = resp.pkt;
+
+    DPRINTF(BusBridge, "trySend response: dest %d addr 0x%x\n",
+            pkt->getDest(), pkt->getAddr());
+
+    bool was_nacked_here = resp.nackedHere;
+
+    if (sendTimingResp(pkt)) {
+        DPRINTF(BusBridge, "  successful\n");
+        // send successful
+        responseQueue.pop_front();
+
+        if (!was_nacked_here) {
+            assert(outstandingResponses != 0);
+            --outstandingResponses;
+        }
+
+        // If there are more packets to send, schedule event to try again.
+        if (!responseQueue.empty()) {
+            resp = responseQueue.front();
+            DPRINTF(BusBridge, "Scheduling next send\n");
+            bridge->schedule(sendEvent,
+                             std::max(resp.ready, curTick() + 1));
+        }
+    } else {
+        DPRINTF(BusBridge, "  unsuccessful\n");
+        inRetry = true;
+    }
+
+    DPRINTF(BusBridge, "trySend: queue size: %d outstanding resp: %d\n",
+            responseQueue.size(), outstandingResponses);
+}
+
+void
+Bridge::BridgeMasterPort::recvRetry()
+{
+    inRetry = false;
+    Tick nextReady = requestQueue.front().ready;
+    if (nextReady <= curTick())
+        trySend();
+    else
+        bridge->schedule(sendEvent, nextReady);
+}
+
+void
+Bridge::BridgeSlavePort::recvRetry()
+{
+    inRetry = false;
+    Tick nextReady = responseQueue.front().ready;
+    if (nextReady <= curTick())
+        trySend();
+    else
+        bridge->schedule(sendEvent, nextReady);
+}
+
+Tick
+Bridge::BridgeSlavePort::recvAtomic(PacketPtr pkt)
+{
+    return delay + masterPort.sendAtomic(pkt);
+}
+
+void
+Bridge::BridgeSlavePort::recvFunctional(PacketPtr pkt)
+{
+    std::list<DeferredResponse>::iterator i;
+
+    pkt->pushLabel(name());
+
+    // check the response queue
+    for (i = responseQueue.begin();  i != responseQueue.end(); ++i) {
+        if (pkt->checkFunctional((*i).pkt)) {
+            pkt->makeResponse();
+            return;
+        }
+    }
+
+    // also check the master port's request queue
+    if (masterPort.checkFunctional(pkt)) {
+        return;
+    }
+
+    pkt->popLabel();
+
+    // fall through if pkt still not satisfied
+    masterPort.sendFunctional(pkt);
+}
+
+bool
+Bridge::BridgeMasterPort::checkFunctional(PacketPtr pkt)
+{
+    bool found = false;
+    std::list<DeferredRequest>::iterator i = requestQueue.begin();
+
+    while(i != requestQueue.end() && !found) {
+        if (pkt->checkFunctional((*i).pkt)) {
+            pkt->makeResponse();
+            found = true;
+        }
+        ++i;
+    }
+
+    return found;
+}
+
+AddrRangeList
+Bridge::BridgeSlavePort::getAddrRanges()
+{
+    return ranges;
+}
+
+Bridge *
+BridgeParams::create()
+{
+    return new Bridge(this);
+}