SLICC: Remove WakeUp* import calls from ast/__init__.py

[gem5.git] / src / mem / tport.hh

diff --git a/src/mem/tport.hh b/src/mem/tport.hh
index df6d481962cca3e32c25bdaa43ca86c9467dae74..91a8ab9a55d639a84052dba2a88755d30336c41f 100644 (file)
--- a/src/mem/tport.hh
+++ b/src/mem/tport.hh
@@ -58,55 +58,91 @@
 class SimpleTimingPort : public Port
 {
   protected:
+    /** A deferred packet, buffered to transmit later. */
+    class DeferredPacket {
+      public:
+        Tick tick;      ///< The tick when the packet is ready to transmit
+        PacketPtr pkt;  ///< Pointer to the packet to transmit
+        DeferredPacket(Tick t, PacketPtr p)
+            : tick(t), pkt(p)
+        {}
+    };
+
+    typedef std::list<DeferredPacket> DeferredPacketList;
+    typedef std::list<DeferredPacket>::iterator DeferredPacketIterator;
+
     /** A list of outgoing timing response packets that haven't been
      * serviced yet. */
-    std::list<Packet*> transmitList;
+    DeferredPacketList transmitList;
+
+    /** This function attempts to send deferred packets.  Scheduled to
+     * be called in the future via SendEvent. */
+    void processSendEvent();
 
     /**
      * This class is used to implemented sendTiming() with a delay. When
-     * a delay is requested a new event is created. When the event time
-     * expires it attempts to send the packet. If it cannot, the packet
-     * is pushed onto the transmit list to be sent when recvRetry() is
-     * called. */
-    class SendEvent : public Event
-    {
-        SimpleTimingPort *port;
-        Packet *packet;
+     * a delay is requested a the event is scheduled if it isn't already.
+     * When the event time expires it attempts to send the packet.
+     * If it cannot, the packet sent when recvRetry() is called.
+     **/
+    Event *sendEvent;
 
-      public:
-        SendEvent(SimpleTimingPort *p, Packet *pkt, Tick t)
-            : Event(&mainEventQueue), port(p), packet(pkt)
-        { setFlags(AutoDelete); schedule(curTick + t); }
+    /** If we need to drain, keep the drain event around until we're done
+     * here.*/
+    Event *drainEvent;
 
-        virtual void process();
+    /** Remember whether we're awaiting a retry from the bus. */
+    bool waitingOnRetry;
 
-        virtual const char *description()
-        { return "Future scheduled sendTiming event"; }
-    };
+    /** Check the list of buffered packets against the supplied
+     * functional request. */
+    bool checkFunctional(PacketPtr funcPkt);
 
+    /** Check whether we have a packet ready to go on the transmit list. */
+    bool deferredPacketReady()
+    { return !transmitList.empty() && transmitList.front().tick <= curTick(); }
 
-    /** Number of timing requests that are emulating the device timing before
-     * attempting to end up on the bus.
-     */
-    int outTiming;
+    Tick deferredPacketReadyTime()
+    { return transmitList.empty() ? MaxTick : transmitList.front().tick; }
 
-    /** If we need to drain, keep the drain event around until we're done
-     * here.*/
-    Event *drainEvent;
+    void
+    schedSendEvent(Tick when)
+    {
+        if (waitingOnRetry) {
+            assert(!sendEvent->scheduled());
+            return;
+        }
+
+        if (!sendEvent->scheduled()) {
+            schedule(sendEvent, when);
+        } else if (sendEvent->when() > when) {
+            reschedule(sendEvent, when);
+        }
+    }
+
+
+    /** Schedule a sendTiming() event to be called in the future.
+     * @param pkt packet to send
+     * @param absolute time (in ticks) to send packet
+     */
+    void schedSendTiming(PacketPtr pkt, Tick when);
 
-    /** Schedule a sendTiming() event to be called in the future. */
-    void sendTimingLater(Packet *pkt, Tick time)
-    { outTiming++; new SendEvent(this, pkt, time); }
+    /** Attempt to send the packet at the head of the deferred packet
+     * list.  Caller must guarantee that the deferred packet list is
+     * non-empty and that the head packet is scheduled for curTick() (or
+     * earlier).
+     */
+    void sendDeferredPacket();
 
     /** This function is notification that the device should attempt to send a
      * packet again. */
     virtual void recvRetry();
 
     /** Implemented using recvAtomic(). */
-    void recvFunctional(Packet *pkt);
+    void recvFunctional(PacketPtr pkt);
 
     /** Implemented using recvAtomic(). */
-    bool recvTiming(Packet *pkt);
+    bool recvTiming(PacketPtr pkt);
 
     /**
      * Simple ports generally don't care about any status
@@ -116,10 +152,8 @@ class SimpleTimingPort : public Port
 
 
   public:
-
-    SimpleTimingPort(std::string pname)
-        : Port(pname), outTiming(0), drainEvent(NULL)
-    {}
+    SimpleTimingPort(std::string pname, MemObject *_owner);
+    ~SimpleTimingPort();
 
     /** Hook for draining timing accesses from the system.  The
      * associated SimObject's drain() functions should be implemented