Merge ktlim@zizzer:/bk/newmem

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

diff --git a/src/mem/bus.hh b/src/mem/bus.hh
index 941389296d9680fe2b893c940b4d20cb9d57fab5..a89738775cb0650292b33b12b6977193cb02cea4 100644 (file)
--- a/src/mem/bus.hh
+++ b/src/mem/bus.hh
@@ -46,11 +46,18 @@
 #include "mem/packet.hh"
 #include "mem/port.hh"
 #include "mem/request.hh"
+#include "sim/eventq.hh"
 
 class Bus : public MemObject
 {
     /** a globally unique id for this bus. */
     int busId;
+    /** the clock speed for the bus */
+    int clock;
+    /** the width of the bus in bytes */
+    int width;
+    /** the next tick at which the bus will be idle */
+    Tick tickNextIdle;
 
     static const int defaultId = -1;
 
@@ -62,9 +69,6 @@ class Bus : public MemObject
     AddrRangeList defaultRange;
     std::vector<DevMap> portSnoopList;
 
-    std::vector<int> snoopCallbacks;
-
-
     /** Function called by the port when the bus is recieving a Timing
       transaction.*/
     bool recvTiming(Packet *pkt);
@@ -105,16 +109,14 @@ class Bus : public MemObject
     /** Snoop all relevant ports atomicly. */
     void atomicSnoop(Packet *pkt);
 
-    /** Snoop for NACK and Blocked in phase 1
-     * @return True if succeds.
-     */
-    bool timingSnoopPhase1(Packet *pkt);
+    /** Snoop all relevant ports functionally. */
+    void functionalSnoop(Packet *pkt);
 
-    /** @todo Don't need to commit all snoops just those that need it
-     *(register somehow). */
-    /** Commit all snoops now that we know if any of them would have blocked.
+    /** Call snoop on caches, be sure to set SNOOP_COMMIT bit if you want
+     * the snoop to happen
+     * @return True if succeds.
      */
-    void timingSnoopPhase2(Packet *pkt);
+    bool timingSnoop(Packet *pkt);
 
     /** Process address range request.
      * @param resp addresses that we can respond to
@@ -181,6 +183,22 @@ class Bus : public MemObject
 
     };
 
+    class BusFreeEvent : public Event
+    {
+        Bus * bus;
+
+      public:
+        BusFreeEvent(Bus * _bus);
+        void process();
+        const char *description();
+    };
+
+    BusFreeEvent busIdle;
+
+    void occupyBus(int numCycles);
+
+    Port * retryingPort;
+
     /** An array of pointers to the peer port interfaces
         connected to this bus.*/
     std::vector<Port*> interfaces;
@@ -189,6 +207,23 @@ class Bus : public MemObject
      * original send failed for whatever reason.*/
     std::list<Port*> retryList;
 
+    void addToRetryList(Port * port)
+    {
+        if (!retryingPort) {
+            // The device wasn't retrying a packet, or wasn't at an appropriate
+            // time.
+            retryList.push_back(port);
+        } else {
+            // The device was retrying a packet. It didn't work, so we'll leave
+            // it at the head of the retry list.
+            retryingPort = NULL;
+
+            // We shouldn't be receiving a packet from one port when a different
+            // one is retrying.
+            assert(port == retryingPort);
+        }
+    }
+
     /** Port that handles requests that don't match any of the interfaces.*/
     Port *defaultPort;
 
@@ -199,8 +234,14 @@ class Bus : public MemObject
 
     virtual void init();
 
-    Bus(const std::string &n, int bus_id)
-        : MemObject(n), busId(bus_id), defaultPort(NULL)  {}
+    Bus(const std::string &n, int bus_id, int _clock, int _width)
+        : MemObject(n), busId(bus_id), clock(_clock), width(_width),
+        tickNextIdle(0), busIdle(this), retryingPort(NULL), defaultPort(NULL)
+    {
+        //Both the width and clock period must be positive
+        assert(width);
+        assert(clock);
+    }
 
 };