A holistic hardware-software approach for fault-aware embedded systems

Fault detection and fault tolerance are a already crucial part of many embedded systems and will become even more important in the future. Reasons are the increasing complexity of software used in safety-critical environments and the trend to execute software components with varying criticality on the same hardware. We propose a novel approach for a flexible and adaptive fault handling. Our approach combines an adaptive hardware architecture with a flexible runtime environment to detect and handle faults. In this paper, we present the structure of a tile-based many-core architecture with runtime-adaptive lockstep cores and the design of a flexible dataflow software framework utilizing this hardware platform. We demonstrate that the hardware overhead for our adaptive lockstep concept and the hardware requirements of our runtime environment are minor and thus allow the use in embedded systems. Furthermore, we verified the fault detection and correction capabilities of both the hardware and software via a hardware fault injection mechanism. In addition, our runtime evaluation shows promising results for different redundancy concepts. For this purpose, we compare the execution time of software-only and hardware-only redundancy solutions as well as combinations of both with a non-redundant baseline for different benchmark applications.