For DMA FIFO depth visualization, in the IDE, select the Graph view, and select the DMA FIFO in the view.
Tip: Hover the mouse on the DMA FIFO to show
information about the DMA FIFO, such as the FIFO depth in words.
The following figure shows an example of DMA FIFO in Graph view:
Figure 1. DMA FIFO in the Graph View
The Trace view also highlights the selected DMA FIFO. Click Trace to switch to the Trace view.
The timeline shows the DMA FIFO size in words (see the following figure). The
Events view shows size
information for the DMA_FIFO_SIZE event.
Figure 2. DMA FIFO in the Trace View
Note: The Trace view shows the DMA FIFO size in multiples of
four. This is because DMA FIFO size only increments after it successfully writes
four words (128 bits) in a memory bank at a time. If the last words is less than
four, the last words is in held inside the S2MM channel, and is never read by
the consumer. The stream must be either continuous or a multiple of four words.
This ensures that the S2MM channel holds no data.
You can use the DMA FIFO information together with other design analyzing techniques to help with design optimization. For additional design analysis techniques, see AI Engine Stall Analysis in the Vitis IDE.