Computer assisted design and integration of FPGA accelerators in aerospace systems

The integration of Field Programmable Gate Arrays (FPGAs) in an aerospace system allows to improve its efficiency and its flexibility thanks to their programmability. To exploit these devices, the designer has to identify the functionalities that have to be executed on them and provide their implementation by means of Hardware Description Languages. Generating these descriptions for a software developer could be a very difficult task because of the different programming paradigms of software programs and hardware descriptions. To facilitate the developer in this activity, High Level Synthesis techniques have been developed aiming at (semi-)automatically generating hardware implementations of specifications written in high level languages (e.g., C). State of the art tools implementing such methodologies have not been designed for the integration with aerospace systems design flows, so significant adaptations could be required to the designer for integrating the hardware implementations with the rest of the design solution. In this paper the integration of a High Level Synthesis design flow in the TASTE framework (http://taste.tuxfamily.org) is presented. TASTE is a set of freely available tools for the development of real time embedded systems developed by the European Space Agency together with a set of its industrial partners. This framework allows to integrate specifications described in different languages (e.g., C, ADA, Simulink, SDL) by means of formal languages (AADL and ASN.1) and to early verify the correctness of the produced solutions. TASTE has been extended with Bambu (http://panda.dei.polimi.it), a tool for the High Level Synthesis developed at Politecnico di Milano. In this way the TASTE users have the possibility to specify which functionalities, provided by means of high level languages such C, have to be implemented in hardware on the FPGA without having to directly provide the hardware implementations. Thanks to the integration of the High Level Synthesis tool indeed, the framework is able not only to produce the hardware implementations, but also to integrate them in the rest of the aerospace system by automatically generating the whole architecture to be implemented on the FPGA. This architecture contains not only the implementation of the hardware accelerators, but also of the components required to transfer the data from and to the rest of the system and to correctly manage their size and endianness. The application of the extended framework to a real case study shows its effective usability.