+ /** a globally unique id for this bus. */
+ int busId;
+ /** the clock speed for the bus */
+ int clock;
+ /** cycles of overhead per transaction */
+ int headerCycles;
+ /** the width of the bus in bytes */
+ int width;
+ /** the next tick at which the bus will be idle */
+ Tick tickNextIdle;
+
+ Event * drainEvent;
+
+
+ static const int defaultId = -3; //Make it unique from Broadcast
+
+ typedef range_map<Addr,int>::iterator PortIter;
+ range_map<Addr, int> portMap;
+
+ AddrRangeList defaultRange;
+
+ typedef std::vector<BusPort*>::iterator SnoopIter;
+ std::vector<BusPort*> snoopPorts;
+
+ /** Function called by the port when the bus is recieving a Timing
+ transaction.*/
+ bool recvTiming(PacketPtr pkt);
+
+ /** Function called by the port when the bus is recieving a Atomic
+ transaction.*/
+ Tick recvAtomic(PacketPtr pkt);
+
+ /** Function called by the port when the bus is recieving a Functional
+ transaction.*/
+ void recvFunctional(PacketPtr pkt);
+
+ /** Timing function called by port when it is once again able to process
+ * requests. */
+ void recvRetry(int id);
+
+ /** Function called by the port when the bus is recieving a status change.*/
+ void recvStatusChange(Port::Status status, int id);
+
+ /** Find which port connected to this bus (if any) should be given a packet
+ * with this address.
+ * @param addr Address to find port for.
+ * @return id of port that the packet should be sent out of.
+ */
+ int findPort(Addr addr);
+
+ // Cache for the findPort function storing recently used ports from portMap
+ struct PortCache {
+ bool valid;
+ int id;
+ Addr start;
+ Addr end;
+ };
+
+ PortCache portCache[3];
+
+ // Checks the cache and returns the id of the port that has the requested
+ // address within its range
+ inline int checkPortCache(Addr addr) {
+ if (portCache[0].valid && addr >= portCache[0].start &&
+ addr < portCache[0].end) {
+ return portCache[0].id;
+ }
+ if (portCache[1].valid && addr >= portCache[1].start &&
+ addr < portCache[1].end) {
+ return portCache[1].id;
+ }
+ if (portCache[2].valid && addr >= portCache[2].start &&
+ addr < portCache[2].end) {
+ return portCache[2].id;
+ }
+
+ return -1;
+ }
+
+ // Clears the earliest entry of the cache and inserts a new port entry
+ inline void updatePortCache(short id, Addr start, Addr end) {
+ portCache[2].valid = portCache[1].valid;
+ portCache[2].id = portCache[1].id;
+ portCache[2].start = portCache[1].start;
+ portCache[2].end = portCache[1].end;
+
+ portCache[1].valid = portCache[0].valid;
+ portCache[1].id = portCache[0].id;
+ portCache[1].start = portCache[0].start;
+ portCache[1].end = portCache[0].end;
+
+ portCache[0].valid = true;
+ portCache[0].id = id;
+ portCache[0].start = start;
+ portCache[0].end = end;
+ }
+
+ // Clears the cache. Needs to be called in constructor.
+ inline void clearPortCache() {
+ portCache[2].valid = false;
+ portCache[1].valid = false;
+ portCache[0].valid = false;
+ }
+
+ /** Process address range request.
+ * @param resp addresses that we can respond to
+ * @param snoop addresses that we would like to snoop
+ * @param id ide of the busport that made the request.
+ */
+ void addressRanges(AddrRangeList &resp, bool &snoop, int id);
+
+ /** Calculate the timing parameters for the packet. Updates the
+ * firstWordTime and finishTime fields of the packet object.
+ * Returns the tick at which the packet header is completed (which
+ * will be all that is sent if the target rejects the packet).
+ */
+ Tick calcPacketTiming(PacketPtr pkt);
+
+ /** Occupy the bus until until */
+ void occupyBus(Tick until);
+
+ /** Ask everyone on the bus what their size is
+ * @param id id of the busport that made the request
+ * @return the max of all the sizes
+ */
+ unsigned findBlockSize(int id);
+