Formal and executable contracts for transaction-level modeling in SystemC

Transaction-Level Modeling (TLM) for systems-on-a-chip (SoCs) has become a standard in the industry, using SystemC. With SystemC/TLM, it is possible to develop an executable virtual prototype of a hardware platform, so that software developers can start writing code long before the actual chip is available. A hardware model in SystemC/TLM can be very abstract, compared to the detailed RTL model. It is clearly component-based, with guidelines defining how components should be designed for use in any TLM context. However, these guidelines are quite informal for the moment. In this paper, we establish a structural correspondence between functional SystemC/TLM models and a formal component-model for embedded systems called 42, for which we have defined a notion of control contract, and an execution mode for systems made of components' contracts. This is a way of formalizing the principles of functional SystemC/TLM. Moreover, it allows the combined use of SystemC/TLM components with 42 components. Demonstrating that such a combined use is possible is key to the adoption of formal components' definitions in the community of TLM users.