US Patent 9021153 Direct memory access system and method using the same

The invention discloses a DMA system capable of being adapted to various interfaces. The DMA system includes the following advantages: 1) the software porting effort can be reduced when different interfaces are integrated into a SoC; 2) a flexible DMA that could provide protocol transparency and could be ported into different interfaces easily; 3) a scalable DMA that can support unlimited TX/RX scattering/gathering data segments; 4) a reusable DMA that provides user defined TX information (or RX information) and TX message (or RX message) field; and 5) a high performance DMA that support unaligned segment data pointers and unlimited scattering/gathering data segments, so as to reduce extra memory copies by CPU.