Cache lookup response filtering

Abstract

Cache invalidation circuitry responds to a cache invalidation command specifying invalidation scope information indicative of at least one invalidation condition, to control a cache to perform an invalidation process to invalidate cache entries satisfying the invalidation condition(s). Cache lookup circuitry issues to the cache a cache lookup request specifying address information, to request that the cache returns a cache lookup response. Cache lookup response filtering circuitry is responsive to a given hit-indicating cache lookup response which provides cached information and invalidation qualifying information returned from a corresponding valid cache entry, to determine whether the given hit-indicating cache lookup response conflicts with an in-progress cache invalidation command, based on the invalidation scope information specified by the in-progress cache invalidation command and the invalidation qualifying information, and when conflict is detected, causes the given hit-indicating cache lookup response to be treated as a miss-indicating cache lookup response.