Ruby: Add support for functional accesses

This patch rpovides functional access support in Ruby. Currently only
the M5Port of RubyPort supports functional accesses. The support for
functional through the PioPort will be added as a separate patch.

1 files changed, 7 insertions, 0 deletions

diff --git a/src/mem/protocol/RubySlicc_Exports.sm b/src/mem/protocol/RubySlicc_Exports.sm
index ccd3aeb7f..2e4a16784 100644
--- a/src/mem/protocol/RubySlicc_Exports.sm
+++ b/src/mem/protocol/RubySlicc_Exports.sm
@@ -57,6 +57,13 @@ enumeration(AccessPermission, desc="...", default="AccessPermission_NotPresent")
   Read_Only,  desc="block is Read Only (modulo functional writes)";
   Read_Write, desc="block is Read/Write";
 
+  // Possibly Invalid data
+  // The maybe stale permission indicates that accordingly to the protocol, 
+  // there is no guarantee the block contains valid data.  However, functional
+  // writes should update the block because a dataless PUT request may
+  // revalidate the block's data.
+  Maybe_Stale, desc="block can be stale or revalidated by a dataless PUT";
+
   // Invalid data
   Invalid,    desc="block is in an Invalid base state";
   NotPresent, desc="block is NotPresent";