Memory controller which implements partial writes with error signaling

Abstract

A requestor of a data processing system provides read access requests, full write access requests with corresponding full write data each having a full-width data size, and partial write access requests with corresponding partial write data each having a partial-width data size onto a system interconnect. A memory array stores write data and corresponding error correction code (ECC) check bits in response to write access requests and provides read data and corresponding ECC check bits for the read data in response to read access requests. A memory controller executes a read-modify-write (RMW) sequence between a store buffer and the memory array to implement a partial write transaction in response to a partial write access request, in which the memory controller stores the partial write data into the store buffer upon receiving the partial write access request and suppresses signaling of ECC errors to the requestor during the RMW sequence.