DMA Pre-Fetch
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C5502 / C5501 DMA Pre-Fetch Feature
The C5502 and C5501 DMA peripheral has a DMA pre-fetch feature to improve data movement performance from non-event driven memory locations. Essentially, when the DMA is configured to move data between memory locations on a synchronized event, it will go ahead and pre-fetch 8 32-bit words from the source location to fill the DMA FIFO. The purpose of this pre-fetch is to improve DMA copy performance because it will only need to perform the write portion of the transfer when the synchronized event occurs.
The only issue with the DMA pre-fetch is if the source memory location is being modified between sync events. This could mean that the DMA FIFO will be filled with incorrect data. To work around this issue, developers need to make sure the source memory location has enough valid data to fill the DMA FIFO.
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