1. A method for operating memory controller circuitry that communicates with external memory, the method comprising: receiving a memory access request at the memory controller circuitry, wherein the memory controller circuitry includes a plurality of color pipelines that are operated in parallel to process memory access requests for different portions of the external memory; decoding the memory access request to identify a target portion of the external memory that is to be accessed; and determining whether the target portion of the external memory has already been assigned to one of the plurality of color pipelines.