Implementation and Impact of an Ultra-Compact Multi-FPGA Board for Large System Prototyping

Efficient prototyping of a large complex system can be significantly facilitated by the use of a flexible and versatile physical platform where both new hardware and software components can readily be implemented and tightly integrated in a timely manner. Towards this end, we have developed the 120 130 mm QFDB board and associated firmware, including the system software environment. We developed a large system based on this advanced dense and modular building block. The QFDB features 4 interconnected Xilinx Zynq Ultrascale+ devices, each one consisting of an ARM-based subsystem tightly coupled with reconfigurable logic. Each Zynq Ultrascale+ is connected to 16 GB of DDR4 memory. In addition, one Zynq provides storage through an M.2 Solid State Disk (SSD). In this paper, we present the design and the implementation of this board, as well as the software environment for board operation. Moreover, we describe a 10 Gb Ethernet communication infrastructure for interconnecting multiple boards together. Finally, we highlight the impact of this board on a number of ongoing research activities that leverage the QFDB versatility, both as a largescale prototyping system for HPC solutions, and as a host for the development of FPGA integration techniques.