Linux Device Drivers Development

DMA - Direct Memory Access

DMA is a feature of computer systems that allows devices to access the main system memory RAM without CPU intervention, which then allows them to devote themselves to other tasks. One typically uses it to accelerate network traffic, but it supports any kind of copy.

The DMA controller is the peripheral responsible for DMA management. One mostly finds it in modern processors and microcontrollers. DMA is a feature used to perform memory read and write operations without stealing CPU cycles. When one needs to transfer a block of data, the processor feeds the DMA controller with the source and destination addresses and the total number of bytes. The DMA controller then transfers the data from the source to the destination ...