A Layered Methodology for the Simulation of Extra-Functional Properties in Smart Systems

Abstract

Smart Systems represent a broad class of intelligent, miniaturized devices incorporating functionality like sensing, actuation, and control. In order to support these functions, they must include sophisticated and heterogeneous components, such as sensors and actuators, multiple power sources and storage devices, digital signal processing, and wireless connectivity. The high degree of heterogeneity typical of smart systems has a heavy impact on their design: the challenges are not in fact restricted to their functionality, but are also related to a number of extra-functional properties, including power consumption, temperature and aging. Current simulation-or model-based design approaches do not target a smart system as a whole, but rather single domains (digital, analog, power devices, etc.) or properties. This paper tries to overcome this limitation by proposing a framework for the concurrent simulation of both functionality and such extra-functional properties. The latter are modeled as different information flows, managed by dedicated "virtual buses" and formalized through the adoption of IP-XACT. SystemC, through the support of physical and continuous time modeling provided by its Analog and Mixed Signal (AMS) extension, is used to implement both functional and extrafunctional models. Experimental results show the efficiency, accuracy and modularity of the proposed approach on an example case study, in which substantial speedups with respect to standard model-based design tools go along with a very high degree of accuracy (< 10 −5 %). Furthermore, the case study highlights that the proposed framework allows to easily capture at run time the mutual impact of properties, e.g., in case of power and temperature.

Towards Multidimensional Verification: Where Functional Meets Non-Functional

“…[35] and [36] focus on the RAS (reliability, availability and serviceability) group of extrafunctional aspects outlined by IBM for complex processor designs where embedded error protection mechanisms and designs intrinsic immunity (due to various masking) to errors is evaluated by fault injection. [43] and [44] propose extensions to system descriptions in the IP-EXACT format to enable multi-layer representation and simulation of several mutually influencing extrafunctional aspects of smart system designs such as lifetime reliability (aging), power and temperature. A complex approach to verification of multiple reliability concerns (soft errors, BTI, etc.)…”

“…[17] available for functional verification. [42], [43], [44], [50], [52], [53], are aimed at methodologies suitable for specific applications (such as cyber-physical system [50]) that assume verification of extra-functional aspects such as power, timing, thermal at the system level.…”

“…There is a very limited number of research works going beyond analysis of one extra-functional verification aspect under constraints of another as the complexity of the problem grows extremely fast with the number of dimensions (interdependent constraints) and the electronic system size. The first works in this direction are, for example, [44] and [70].…”