Fault injection at host-compiled level with static fault set reduction for SoC firmware robustness testing

Abstract

Decreasing hardware reliability makes robust firmware imperative for safety-critical applications. Hence, ensuring correct handling of errors in peripherals is a key objective during firmware design. To adequately support robustness considerations of firmware designers during implementation, an efficient qualitative fault injection method is required. This paper presents a high-speed fault injection technique based on host-compiled firmware simulation that is suitable to analyze the impact of transient faults on firmware behavior. Additionally, fault set reduction by static code analysis avoids unnecessary injection of masked and equivalent faults. Application of the proposed fault injection technique on an industrial safety-relevant automotive system-on-chip (SoC) firmware demonstrates at least three orders of magnitude speedup compared to instruction set level. In addition, a fault set reduction by 78% is achieved. While significantly reducing the required fault injection time, the presented techniques provide as accurate feedback to the designer as existing state-of-the-art approaches.