Method and system for initiating and loading DMA controller registers by using user-level programs

摘要

In a computer system the typically high overhead requirement for CPU instructions to operate a conventional direct memory access (DMA) controller are reduced to two user-level memory references via User-level Direct Memory Access (UDMA). The UDMA apparatus is located between the CPU and a DMA Controller, whereby the UDMA is programmed to use existing virtual memory translation hardware of the associated computer system to perform permission checking and address translation without Kernel involvement, and otherwise use minimal Kernel involvement for other operations.