FPGA-Based Performance and Reliability Evaluation of the MicroBlaze VRISC-V Soft-Core for Aerospace Systems

Abstract

There are a variety of RISC-V soft-cores available for implementation in FPGAs, and they are increasingly being considered for space applications in harsh environments. This paper investigates the performance and reliability of the Xilinx's soft-core MicroBlaze V. Ten different configurations of MicroBlaze V are evaluated using OnBoard Processing Benchmarks (OBPMark), analyzing the impact of architectural parameters and memory interfaces. In addition, a direct comparison between MicroBlaze V and the CV32E40P RISC-V core is conducted under an identical system-on-chip environment using AXI-based memory access. Reliability is further evaluated through configuration-memory fault injection, considering both unhardened designs and implementations protected with Xilinx Triple Modular Redundancy (TMR). The results demonstrate that MicroBlaze V is more optimized for FPGA implementation, achieving higher performance and operating frequency with lower resource usage, making it more suitable for TMR-based designs. While the CV32E40P shows improved power efficiency for applications without floating-point operations, it uses significantly more resources. Fault-injection experiments indicate that pipeline optimization has limited impact on reliability, with similar fault tolerance observed across configurations.