Merge ktlim@zizzer:/bk/newmem

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

diff --git a/src/mem/bus.hh b/src/mem/bus.hh
index 9c7054b9494f341bd4013ac52705d4a1d250f9c1..a89738775cb0650292b33b12b6977193cb02cea4 100644 (file)
--- a/src/mem/bus.hh
+++ b/src/mem/bus.hh
@@ -30,7 +30,8 @@
  */
 
 /**
- * @file Decleration of a bus object.
+ * @file
+ * Declaration of a bus object.
  */
 
 #ifndef __MEM_BUS_HH__
@@ -45,25 +46,35 @@
 #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;
 
     struct DevMap {
         int portId;
         Range<Addr> range;
     };
     std::vector<DevMap> portList;
-
+    AddrRangeList defaultRange;
+    std::vector<DevMap> portSnoopList;
 
     /** Function called by the port when the bus is recieving a Timing
-        transaction.*/
+      transaction.*/
     bool recvTiming(Packet *pkt);
 
     /** Function called by the port when the bus is recieving a Atomic
-        transaction.*/
+      transaction.*/
     Tick recvAtomic(Packet *pkt);
 
     /** Function called by the port when the bus is recieving a Functional
@@ -86,6 +97,27 @@ class Bus : public MemObject
      */
     Port *findPort(Addr addr, int id);
 
+    /** Find all ports with a matching snoop range, except src port.  Keep in mind
+     * that the ranges shouldn't overlap or you will get a double snoop to the same
+     * interface.and the cache will assert out.
+     * @param addr Address to find snoop prts for.
+     * @param id Id of the src port of the request to avoid calling snoop on src
+     * @return vector of IDs to snoop on
+     */
+    std::vector<int> findSnoopPorts(Addr addr, int id);
+
+    /** Snoop all relevant ports atomicly. */
+    void atomicSnoop(Packet *pkt);
+
+    /** Snoop all relevant ports functionally. */
+    void functionalSnoop(Packet *pkt);
+
+    /** Call snoop on caches, be sure to set SNOOP_COMMIT bit if you want
+     * the snoop to happen
+     * @return True if succeds.
+     */
+    bool timingSnoop(Packet *pkt);
+
     /** Process address range request.
      * @param resp addresses that we can respond to
      * @param snoop addresses that we would like to snoop
@@ -94,7 +126,7 @@ class Bus : public MemObject
     void addressRanges(AddrRangeList &resp, AddrRangeList &snoop, int id);
 
 
-    /** Decleration of the buses port type, one will be instantiated for each
+    /** Declaration of the buses port type, one will be instantiated for each
         of the interfaces connecting to the bus. */
     class BusPort : public Port
     {
@@ -151,6 +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;
@@ -159,6 +207,26 @@ 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;
+
   public:
 
     /** A function used to return the port associated with this bus object. */
@@ -166,8 +234,14 @@ class Bus : public MemObject
 
     virtual void init();
 
-    Bus(const std::string &n, int bus_id)
-        : MemObject(n), busId(bus_id)  {}
+    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);
+    }
 
 };