Soft-Error Analysis of Self-reconfiguration Controllers for Safety Critical Dynamically Reconfigurable FPGAs

Reconfigurable SRAM-based Field Programmable Gate Arrays are increasingly deployed in the aerospace applications, due to their enhanced flexibility, high performance and run-time reconfiguration capabilities. The possibility to adapt on-the-fly the circuit functionality is made possible by the Internal Configuration Access Port (ICAP) that can be managed from the application through a dedicated controller. This feature enables the deployment of new optimized reconfigurable architectures for computationally intensive and fault-tolerant applications. In this context, a promising architecture is the Dynamically Reconfigurable Processing Module (DRPM), an FPGA-based modular system where the content of each reconfigurable module can be rewritten, overwritten or erased to perform performance optimization and functional modification at run-time. However, when these systems are adopted in avionic and space applications, SRAM configuration sensitivity to radiation induced soft-errors should be addressed. In this work, we evaluate the soft-error sensitivity of upsets in the configuration memory of two implementations of the ICAP controller within a DRPM system. We performed a radiation test campaign and a selective fault injection of upsets on the ICAP controller configuration memory to mimic the radiation profiles. The comparative analysis showed meaningful guidelines on the implementations of self-reconfigurable systems for the aerospace domain: the controller with distributed memory results the 28% more tolerant to low radiation environment compared to the integrated memory version, which in return results the 25% more robust considering radiation particles with higher energies.