Memory controller and method for controlling data in decoding pipeline

Abstract

A memory controller, for use in a data storage device, is provided. A low-density parity-check (LDPC) decoding procedure performed by the memory controller includes an initial phase, a decoding phase, and an output phase in sequence. The memory controller includes a memory-index control circuit and a decoder. The decoder includes a decoding pipeline to perform the decoding phase of the LDPC decoding procedure. After the data storage device is booted up, the decoder reads a plurality of first codewords from a variable-node memory using a first order via the memory-index control circuit for LDPC decoding. In response to the decoder determining that a specific codeword among the first codewords has decoding failure, the decoder is reset to read a plurality of second codewords from the variable-node memory using a second order via the memory-index control circuit for LDPC decoding. The first order is different from the second order.