Complex safety mechanisms require interoperability and automation for validation and metric closure
A three step workflow for efficient fault injection
One practice to achieve or maintain a safe state is running an exhaustive fault campaign to test the effectiveness of a safety architecture’s ability to detect faults or control failures. While traditional approaches may have been satisfactory in the past, the increased size and complexity of automotive designs with the large number of faults that need to be tested make performing safety verification using a single technology impractical. Developing an optimized safety methodology with specific fault lists automatically targeted for simulation, emulation and formal is challenging. Another challenge is consolidating fault resolution results from various fault injection runs for final metric computation. In this paper we will discuss the details of the functional safety methodology we used for this application using an SoC level automotive test case, and we will show how our methodology produces a scalable, efficient safety workflow using optimization techniques for fault injection using formal, simulation, and emulation verification engines.
Optimizing the safety workflow
The race to autonomous mobility among the automobile manufacturers is driving the evolution of the underlying semiconductors. As a result, semiconductor technologies are moving towards higher densities and lower operating voltages, and this migration is introducing increasing sensitivity to random hardware failures – the failures which occur unpredictably over a semiconductor’s lifetime. Modern cars deploying ADAS and AV features rely on these digital and analog systems to perform critical real-time applications. This reliance has led to a concern over validation of these systems.
Interoperability of fault injection engines, optimization techniques, and an automated flow can effectively reduce overall execution time to quickly close-the-loop from safety analysis to safety certification. Fault injection engines used in the safety workflow include formal, simulation, and emulation. Each engine has specific benefits and can reduce overall fault injection time when used together in the three-step safety workflow:
Step 1:
Generate the optimized fault list
Step 2:
Fault injection and classification
Step 3:
Generate the metrics report