Port: Add protocol-agnostic ports in the port hierarchy

This patch adds an additional level of ports in the inheritance
hierarchy, separating out the protocol-specific and protocl-agnostic
parts. All the functionality related to the binding of ports is now
confined to use BaseMaster/BaseSlavePorts, and all the
protocol-specific parts stay in the Master/SlavePort. In the future it
will be possible to add other protocol-specific implementations.

The functions used in the binding of ports, i.e. getMaster/SlavePort
now use the base classes, and the index parameter is updated to use
the PortID typedef with the symbolic InvalidPortID as the default.

1 files changed, 10 insertions, 6 deletions

diff --git a/src/mem/mem_object.hh b/src/mem/mem_object.hh
index 6cc0c4fd3..e12b30661 100644
--- a/src/mem/mem_object.hh
+++ b/src/mem/mem_object.hh
@@ -67,26 +67,30 @@ class MemObject : public ClockedObject
     MemObject(const Params *params);
 
     /**
-     * Get a master port with a given name and index.
+     * Get a master port with a given name and index. This is used at
+     * binding time and returns a reference to a protocol-agnostic
+     * base master port.
      *
      * @param if_name Port name
      * @param idx Index in the case of a VectorPort
      *
      * @return A reference to the given port
      */
-    virtual MasterPort& getMasterPort(const std::string& if_name,
-                                      int idx = -1);
+    virtual BaseMasterPort& getMasterPort(const std::string& if_name,
+                                          PortID idx = InvalidPortID);
 
     /**
-     * Get a slave port with a given name and index.
+     * Get a slave port with a given name and index. This is used at
+     * binding time and returns a reference to a protocol-agnostic
+     * base master port.
      *
      * @param if_name Port name
      * @param idx Index in the case of a VectorPort
      *
      * @return A reference to the given port
      */
-    virtual SlavePort& getSlavePort(const std::string& if_name,
-                                    int idx = -1);
+    virtual BaseSlavePort& getSlavePort(const std::string& if_name,
+                                        PortID idx = InvalidPortID);
 };
 
 #endif //__MEM_MEM_OBJECT_HH__