Reseach And Implementation Of An Interaction Mechanism Of Mutil-channel PCI Express Device And Linux System

In order to enhance the data exchange capabilities between multi-channel devices and Linux systems. This paper design and implement a high-speed device driver based on PCI Express bus and DMA Ringbuffer model.This paper analyzes the maximum effective bandwidth of DMA transfers of the PCI Express bus equipment and analyzes the interrupt request process, the interrupt handling process and the corresponding wasting of the equipment under x86 architecture. According to the theoretical analysis we establish an independent DMA Ringbuffer model and uses interrupt latency and interrupt timer to improve the efficiency of NAPI mechanism. Finally, we implement a driver with this DMA model and complete the corresponding experiment.The device driver is designed to achieve 64B packet 800Mbps throughput and 1518B packet 3.6Gbps throughput. The driver can be used in a variety of processor platforms.