DMA FIFO - 2021.2 English

Versal ACAP AI Engine Programming Environment User Guide (UG1076)

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2021.2 English

A fifo_depth() constraint specification above 40 allocates FIFOs from memory, known as DMA FIFOs. The following is an example of a FIFO allocation for a request of fifo_depth(3000) bytes which is allocated in memory.

Figure 1. DMA FIFO Allocation

Note: The maximum allowable FIFO depth value is 8188 32-bit words.

You can also specify the type of FIFO allocated, whether stream switch or DMA, as well as their locations. More information can be found in FIFO Location Constraints.