ruby: improved support for functional accesses

This patch adds support to different entities in the ruby memory system
for more reliable functional read/write accesses. Only the simple network
has been augmented as of now. Later on Garnet will also support functional
accesses.
The patch adds functional access code to all the different types of messages
that protocols can send around. These messages are functionally accessed
by going through the buffers maintained by the network entities.
The patch also rectifies some of the bugs found in coherence protocols while
testing the patch.

With this patch applied, functional writes always succeed. But functional
reads can still fail.

1 files changed, 36 insertions, 0 deletions

diff --git a/src/mem/slicc/symbols/StateMachine.py b/src/mem/slicc/symbols/StateMachine.py
index bb69b70bf..427dbf700 100644
--- a/src/mem/slicc/symbols/StateMachine.py
+++ b/src/mem/slicc/symbols/StateMachine.py
@@ -269,6 +269,9 @@ class $c_ident : public AbstractController
     void recordCacheTrace(int cntrl, CacheRecorder* tr);
     Sequencer* getSequencer() const;
 
+    bool functionalReadBuffers(PacketPtr&);
+    uint32_t functionalWriteBuffers(PacketPtr&);
+
 private:
 ''')
 
@@ -987,6 +990,39 @@ $c_ident::${{action.ident}}(const Address& addr)
         for func in self.functions:
             code(func.generateCode())
 
+        # Function for functional reads from messages buffered in the controller
+        code('''
+bool
+$c_ident::functionalReadBuffers(PacketPtr& pkt)
+{
+''')
+        for var in self.objects:
+            vtype = var.type
+            if vtype.isBuffer:
+                vid = "m_%s_ptr" % var.c_ident
+                code('if ($vid->functionalRead(pkt)) { return true; }')
+        code('''
+                return false;
+}
+''')
+
+        # Function for functional writes to messages buffered in the controller
+        code('''
+uint32_t
+$c_ident::functionalWriteBuffers(PacketPtr& pkt)
+{
+    uint32_t num_functional_writes = 0;
+''')
+        for var in self.objects:
+            vtype = var.type
+            if vtype.isBuffer:
+                vid = "m_%s_ptr" % var.c_ident
+                code('num_functional_writes += $vid->functionalWrite(pkt);')
+        code('''
+    return num_functional_writes;
+}
+''')
+
         code.write(path, "%s.cc" % c_ident)
 
     def printCWakeup(self, path, includes):