Debugging Xilinx Zynq-7000 SoC Processor Caches during Linux System Execution under Proton Irradiation

Caches are vitally important for the performance in modern CPUs. But they also bear great potential for malfunction when put under irradiation. Hence, trade-offs have to be made for either performance or reliability.In this paper we present a deeper insight on the CPU caches, their influence in a running operating system and possible reasons for their malfunction. Therefore, a proton source with 230 MeV was used to target an ARM Cortex A9 in a Zynq-7000, running an embedded Linux with KGDB. As a result, we tested three different cache configurations, which showed three distinct error cases. This can help to improve the understanding of system malfunctions due to radiation and build useful mitigation techniques.