A cache has programmable, finely ganular, locked-down regions within a way or way(s) so that the contents of the locked-down regions are not evicted. The finely granular locked-down regions need not be contiguous and are programmed as either "locked-valid" or "locked-invalid" to provide general purpose memory that is local and private to the processor or for masking defected cache lines or portions thereof. Finely granular, programmable spatial regions of the cache that are locked-down are preferably, although not exclusively, programmed through two additional states to the standard MESI (Modified, Exclusive, Shared, Invalid) protocol for multipurpose cache coherency.