From the data-sheet for SAME70x21, UART seems to be lacking HW-FIFO, yet DMA is supported. From the UART driver code, it's clear that buffers are used but it's unclear if send/recieve depends on IRQ:s or are managed by HW. I need to send blocks of data where back-to back latency must not exceed 2.5 periods of the bit-rate where the bit-rate is somewhat pushing SAM's HW-limits (6Mbps).
Please advice