  We address the problem of performing message-passing-based decoding of
quantum LDPC codes under hardware latency limitations. We propose a novel way
to do layered decoding that suits quantum constraints and outperforms flooded
scheduling, the usual scheduling on parallel architectures. A generic
construction is given to construct layers of hypergraph product codes. In the
process, we introduce two new notions, t-covering layers which is a
generalization of the usual layer decomposition, and a new scheduling called
random order scheduling. Numerical simulations show that the random ordering is
of independent interest as it helps relieve the high error floor typical of
message-passing decoders on quantum codes for both layered and serial decoding
without the need for post-processing.
