A Flexible Interface Architecture for Reconfigurable Coprocessors in Embedded Multicore Systems using PCIe Single-Root I/O Virtualization

Especially in complex system-of-systems scenarios, where multiple high-performance or real-time processing functions need to co-exist and interact, reconfigurable devices together with virtualization techniques show considerable promise to increase efficiency, ease integration and maintain functional and non-functional properties of the individual functions. In this paper, we propose a flexible interface architecture with low overhead for coupling reconfigurable coprocessors to high-performance general-purpose processors, allowing customized yet efficient construction of heterogeneous processing systems. Our implementation is based on PCI Express (PCIe) and optimized for virtualized systems, taking advantage of the SR-IOV capabilities in modern PCIe implementations. We describe the interface architecture and its fundamental technologies, detail the services provided to individual coprocessors and accelerator modules, and quantify key corner performance indicators relevant for virtualized applications.