diff options
Diffstat (limited to 'src/mem/protocol')
| -rw-r--r-- | src/mem/protocol/RubySlicc_Exports.sm | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/src/mem/protocol/RubySlicc_Exports.sm b/src/mem/protocol/RubySlicc_Exports.sm index e8616521a..ca80047f7 100644 --- a/src/mem/protocol/RubySlicc_Exports.sm +++ b/src/mem/protocol/RubySlicc_Exports.sm @@ -63,6 +63,14 @@ enumeration(AccessPermission, desc="...", default="AccessPermission_NotPresent") // 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"; + // In Broadcast/Snoop protocols, memory has no idea if it is exclusive owner + // or not of a block, making it hard to make the logic of having only one + // read_write block in the system impossible. This is to allow the memory to + // say, "I have the block" and for the RubyPort logic to know that this is a + // last-resort block if there are no writable copies in the caching hierarchy. + // This is not supposed to be used in directory or token protocols where + // memory/NB has an idea of what is going on in the whole system. + Backing_Store, desc="for memory in Broadcast/Snoop protocols"; // Invalid data Invalid, desc="block is in an Invalid base state"; |