Cache memory system and method for automatically locking cache entries to prevent selected memory items from being replaced

摘要

A cache memory system has a plurality of cache entries for storing memory items staged from a memory. The cache memory system locks entries so that memory items stored therein are prevented from being replaced by newly staged memory items. Entries can be locked globally whereby more than one entry is locked. Entries can also be locked locally whereby only selected ones of the entries are locked. The cache memory system can also set or clear a representation in an entry representing that such entry is not to be replaced upon being selectively activated or deactivated by an auto-lock (automatic lock) signal. The representation is memory-mapped and can be set or cleared directly by an integer unit.