A complete self-testing and self-configuring NoC infrastructure for cost-effective MPSoCs

Abstract

Networks-on-chip need to survive to manufacturing faults in order to sustain yield. An effective testing and configuration strategy however implies two opposite requirements. One one hand, a fast and scalable built-in self-testing and self-diagnosis procedure has to be carried out concurrently at NoC switches. On the other hand, programming the NoC routing mechanism to go around faulty links and switches can be optimally performed by a centralized controller with global network visibility. To the best of our knowledge, this article proposes for the first time a global network testing and configuration strategy that meets the opposite requirements by means of a fault-tolerant dual network architecture and a fast configuration algorithm for the most common failure patterns. Experimental results report an area overhead as low as 12.5% with respect to the baseline switch architecture while achieving a high degree of fault tolerance. In fact, even when multiple stuck-at faults are considered, the capability of fault masking by the dual network is always over 80%, and the support for multiple link failures is more than 90% in presence of two unusable links in the main network with minimum set-up times.

A Brief Comment on “A Complete Self-Testing and Self-Configuring NoC Infrastructure for Cost-Effective MPSoCs” [ACM Transactions on Embedded Computing Systems 12 (2013) Article 106]

“…The purpose of this comment is to demonstrate the inconsistency of fast self-configuration method presented in [Ghiribaldi et al 2013]. To handle inconsistency, we present the correct set of LBDR bits and also argue that complete reconfiguration of routing instance is mandatory to handle some fault combinations.…”

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In the paper [Ghiribaldi et al 2013], a complete self-testing and self configuring NoC infrastructure for cost effective MPSoCs was presented in order to make NoC architecture tolerant to faults. To overcome the complexity involved during the complete reconfiguration of routing instance in face of most of the usual failure patterns, authors [Ghiribaldi et al 2013] proposed a fast self reconfiguration algorithm.

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“…To overcome the complexity involved during the complete reconfiguration of routing instance in face of most of the usual failure patterns, authors [Ghiribaldi et al 2013] proposed a fast self reconfiguration algorithm. The algorithm is based on segment based routing implemented using LBDR (Logic Based Distributed Routing) and claimed to have handled most common NoC faults.The purpose of this comment is to demonstrate the inconsistency of fast self-configuration method presented in [Ghiribaldi et al 2013]. To handle inconsistency, we present the correct set of LBDR bits and also argue that complete reconfiguration of routing instance is mandatory to handle some fault combinations.…”

“…To handle inconsistency, we present the correct set of LBDR bits and also argue that complete reconfiguration of routing instance is mandatory to handle some fault combinations. New coverage results of the fast self reconfiguration algorithm of [Ghiribaldi et al 2013] are also presented. …”

“…To overcome the complexity involved during the complete reconfiguration of routing instance in face of most of the usual failure patterns, authors [Ghiribaldi et al 2013] proposed a fast self reconfiguration algorithm. The algorithm is based on segment based routing implemented using LBDR (Logic Based Distributed Routing) and claimed to have handled most common NoC faults.…”