Implementation of High-throughput PCIe based on FPGA and PowerPC

Abstract

This paper designed and implemented a direct memory access (DMA) architecture of PCI-Express (PCIe) between Xilinx field programmable gate array (FPGA) and Freescale PowerPC. The DMA architecture based on FPGA is compatible with the Xilinx PCIe core while the DMA architecture based on POWERPC is compatible with VxBus of VxWorks. The solutions provide a high-performance and low-occupancy alternative to commercial products. In order to maximize the PCIe throughput while minimizing the FPGA resources utilization, a novel strategy for the DMA engine is adopted, where the DMA register list is stored not only inside the FPGA during initialization phase but also in the central memory of the host CPU. The FPGA design package is complemented with simple register access to control the DMA engine by a VxWorks driver. The design is compatible with Xilinx FPGA Kintex Ultrascale Family, and operates with the Xilinx PCIe endpoint Generation 1 with lane configurations x8. A data throughput of more than 666 MBytes/s (memory write with data from FPGA to PowerPC) has been achieved with the single PCIe Gen1 x8 lanes endpoint of this design.