Direct Memory Access Controller with Hybrid Scatter-Gather Functionality

摘要

A direct memory access (DMA) controller stores a set of DMA instructions in a list, where each entry in the list includes a bit field that identifies the type of the entry. Based on the bit field, the DMA controller determines whether each DMA instruction is a buffer pointer or a jump pointer. If a DMA instruction is identified as a buffer pointer, the DMA controller transfers data to or from the location specified by the buffer pointer. If a DMA instruction is identified as a jump pointer, the DMA controller jumps to the location in the list specified by the jump pointer. A subset of the list of DMA instructions may be cached, and the DMA controller executes the cache entries sequentially. If a jump pointer is encountered in the cache, the DMA controller flushes the cache and reloads it from main memory based on the jump pointer.

主权项

1. A DMA controller comprising:
a control unit configured to perform a data transfer over a bus coupled with the DMA controller, wherein the control unit is further configured to perform a plurality of data transfers using one or more lists of DMA instructions stored in memory, and wherein the control unit will read address information from each list entry, and wherein the address information is determined to be either a buffer pointer or a jump pointer based on at least one bit within each list entry.