VerCoLib: Fast and Versatile Communication for FPGAs via PCI Express

摘要

PCI Express plays a vital role in including FPGA accelerators into high-performance computing systems. This also includes direct communication between multiple FPGAs, without any involvement of the main memory of the host. We present a highly configurable hardware interface that supports DMA-based connections to a host system as well as direct communication between multiple FPGAs. Our implementation offers unidirectional channels to connect FPGAs, allowing for precise adaptation to all kinds of use cases. Multiple channels to the same endpoint can be used to realise independent data transmissions. While the main focus of this work is flexibility, we are able to show maximum throughput for connections between two FPGAs and up to 92% of the available bandwidth for connections between the FPGA and the host system.