Configuration Scrubbing Architectures for High-Reliability FPGA Systems
Aaron Gerald StoddardConf i guration scrubbing is an upset mitigation technique that detects and corrects upsets in an FPGA’s conf i guration memory. Conf i guration scrubbing periodically moni-tors an FPGA’s conf i guration memory utilizing mechanisms such as Error Correction Codes (ECCs), Cyclic Redundancy Checks (CRCs), a protected golden f i le, and partial reconf i gu-ration to detect and correct upset memory bits. This work presents improved Xilinx 7-Series conf i guration scrubbing architectures that achieve minimal hardware footprints, competitive performance metrics, and robust detection and correction capabilities.
The two principal scrubbing architectures presented in this work are the readback and hybrid scrubbers which detect and correct Single Bit Upsets (SBUs) and Multi-Bit Upsets (MBUs). Harnessing the performance advantages granted by the 7-Series internal Readback CRC scan, a hybrid scrubber built in software for the Zynq XZC07020 FPGA has been measured to correct SBUs in 8.024 ms, even-numbered MBUs in 13.38 ms, and odd-numbered MBUs in 21.40 ms. It can also perform a full readback scrub of the entire device in under two seconds. These scrubbing architectures were validated in radiation beam tests, where one of the architectures corrected MBUs as large as sixteen bits in a single frame.