1687-3963-2007-039161 1687-3963 Research Article <p>Formal Methods for Scheduling of Latency-Insensitive Designs</p> BoucaronJulienjulien.boucaron@inria.fr de SimoneRobertrobert.de_simone@inria.fr MilloJean-Vivienjean-vivien.millo@inria.fr

Aoste project-team, INRIA Sophia-Antipolis, 2004 rouye des Iucioles, BP 93, Sophia Antipolis Cedex 06902, France

 EURASIP Journal on Embedded Systems 1687-3963 2007 20071 039161 http://jes.eurasipjournals.com/content/2007/1/039161 10.1155/2007/39161 172006231200711520073082007 2007Boucaron et al.This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Latency-insensitive design (LID) theory was invented to deal with SoC timing closure issues, by allowing arbitrary fixed integer latencies on long global wires. Latencies are coped with using a resynchronization protocol that performs dynamic scheduling of data transportation. Functional behavior is preserved. This dynamic scheduling is implemented using specific synchronous hardware elements: relay-stations (RS) and shell-wrappers (SW). Our first goal is to provide a formal modeling of RS and SW, that can be then formally verified. As turns out, resulting behavior is k-periodic, thus amenable to static scheduling. Our second goal is to provide formal hardware modeling here also. It initially performs throughput equalization, adding integer latencies wherever possible; residual cases require introduction of fractional registers (FRs) at specific locations. Benchmark results are presented, run on our Kpassa tool implementation.

 Synchronous Paradigm in Embedded Systems

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