A Distributed Clustered Architecture to Tackle Delay Variations in Datapath Synthesis

Due to the necessity of handling unexpected events in execution time, e.g., to support process variations, new mechanisms for dealing with every possible behavior of the datapath must be developed. Conventional centralized controllers can only handle very few dynamic events. Distributed controllers, on the other hand, are able to support every combination of events. These controllers are composed of several finite state machines, which are interconnected via a global coordinator. The use of this type of controller obliges to check the hazards between operations in run time, which entails some penalty in the controller complexity. In this paper, a new methodology for deploying a distributed controller over a set of clusters is presented. A register binding algorithm specially suited for distributed controllers has also been developed. It combines a clustering method and a least recently used policy to reduce the number of hazards in run time. Furthermore, our methodology allows the exploration of different solutions by tuning the input parameters of the binding algorithm. Several studies evaluating the execution time and area tradeoffs are presented to support our techniques. Results show that for some cases it is possible to reduce more than 50% the expected execution time, at the expense of a slight area increase.