RePQC: A 3.4-uJ/Op 48-kOPS Post-Quantum Crypto-Processor for Multiple-Mathematical Problems

Post-quantum cryptography (PQC) is investigated to replace the classical public cryptography algorithms, which would be completely broken by large-scale quantum computers. However, current PQC schemes have completely different mathematical foundations and parameter sets, which makes the implementation of unified PQC processor extremely challenging. To address this issue, an agile PQC processor, RePQC, is proposed in this work to support schemes on multiple mathematical problems. First, the hierarchical calculation framework, ranging from algorithm level, task level, and coefficient level, is proposed to achieve desirable flexibility and energy efficiency. Second, a hybrid processing element array is built to support arithmetic and logical operations simultaneously, while algorithm-hardware co-design is utilized in task-level schedulers to further improve the algorithm-oriented energy efficiency. Finally, parallelism exploration and algorithm-level computation transformation is further utilized to optimize the configuration on RePQC for higher throughput. Fabricated in a 28-nm process, RePQC achieves the energy efficiency of 3.4 uJ/Op and the throughput of 48 kOPS, which is <inline-formula> <tex-math notation="LaTeX">$2\times $ </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">$23\times $ </tex-math></inline-formula> higher than the state-of-the-art work, respectively. To the best of our knowledge, RePQC is the first silicon-proven PQC processor for different mathematical problems.