METHOD AND APPARATUS FOR SELECTIVELY PERFORMING EXPLICIT AND IMPLICIT DATA LINE READS ON AN INDIVIDUAL SUB-CACHE BASIS

摘要

A method and apparatus are described for selectively performing explicit and implicit data line reads. A controller, located in a cache, individually monitors the data resource availability for each of a plurality of sub-caches also located in the cache. The controller receives a data line request, generates an individual implicit tag request for each of the sub-caches that currently have sufficient data resources to perform an implicit data line read, and generates an individual explicit tag request for each of the sub-caches that do not currently have sufficient data resources to perform an implicit data line read. Each tag request includes an address of the requested data line and an indicator, (represented by at least one bit), of whether the tag request is an explicit or implicit tag request.