Integrating error correction and detection techniques in RISC-V processor microarchitecture for enhanced reliability

An essential consideration in processor design is ensuring reliability, particularly in demanding environments such as outer space and nuclear plants. To mitigate the effects of errors and enable error recovery, processors need to incorporate fault tolerance techniques. One common type of error is SEU (Single Event Upset), which affects various microelectronic devices including microprocessors, microcontrollers, and semiconductor memory devices. While error mitigation techniques have been developed for processors based on architectures like ARM (Advanced RISC Machine) and MIPS (Million Instructions Per Second), there is a gap in research for open-source ISAs (Instruction Set Architecture) like RISC-V, which this paper aims to address. This paper focuses on designing a fault-tolerant microarchitecture for a RISC-V processor that can correct one-bit errors, detect up to two-bit errors, and integrate lockstep and pipeline rollback features at a lower LUTs (Look Up Tables) consumption by re-using the same hardware pipeline for error mitigation and recovery through instruction mimicking. By incorporating these features, the proposed approach enhances the system’s fault tolerance by detecting and correcting errors caused by transient events and achieves a lower effective die size upon realization compared to contemporary works. The proposed microarchitecture design was simulated and synthesized using the Vivado Design Suite 2023.1 and implemented on a Zynq 7000 SoC ZC702 Evaluation Kit.