Provably Relevant HAL Interface Requirements for Embedded Systems

Abstract

Embedded applications often use a Hardware Abstraction Layer (HAL) to access hardware. Improper use of the HAL can lead to incorrect hardware operations, resulting in system failure and potentially serious damage to the hardware. The question is how one can single out, among a possibly large set of HAL interface requirements, those that are indis- putably relevant for preventing this kind of system failure. In this paper, we introduce a formal notion of relevance. This allows us to leverage a formal method, i.e., software model checking, to produce a mathematical proof that a requirement is indisputably rele- vant. We propose an approach to extract provably relevant requirements from issue reports on system failures. We present a preliminary case study to demonstrate that the approach is feasible in principle. The case study uses three examples of issue reports on embedded applications that use the SPI bus via the spidev HAL. The overall con- tribution of this paper is to pave the way for the study of approaches that support the systematic identification of requirements essential for preventing a specific kind of system failure.