A rule-based model of computation for SystemC: integrating SystemC and Bluespec for co-design

Bluespec´s rule-based model of computation (MoC) for hardware concurrency has gained attention for several reasons. From its basis in term rewriting systems, rules have the property of atomicity, which improves correctness by construction, particularly in large-scale concurrency with finegrained, dynamic resource sharing (typical in complex hardware). Rule-based interface methods extend atomicity across module boundaries, have a natural transactional reading, and precisely and formally characterize resource-sharing constraints. All this can be synthesized to hardware with competitive quality. SystemC expresses concurrency with threading and events, just like RTL, where it is difficult to deal with fine-grain concurrency and resource sharing. Further, there is no systematic methodology for module composition. Thus, while SystemC is suitable for very coarse modeling and for embedded software development, its limitations make it difficult to model correct by construction hardware systems accurately. In this paper, we show how to integrate Bluespec´s rule-based MoC into SystemC. We augment SystemC modules with rules and rule-based interface methods, and augment the SystemC simulation kernel with a rule execution kernel. The integration is augmentative in that a model can contain both rule-based modules (where hardware accuracy is desired) as well as core SystemC or TLM modules (for embedded software, instruction-set simulators, existing SystemC IP, or pure behavioral models), thus providing the advantages of each MoC where appropriate