On 11/05/2014 05:20 PM, Lennart Sorensen wrote: > On Wed, Nov 05, 2014 at 10:33:15AM -0500, Lennart Sorensen wrote: >> Two systems ran 16 hours each so far with no issues. Pushed 170MB of >> data through the pair of serial ports on one system at 230400. > > The console on uart3 doesn't appear to be using the dma assuming the > values in /sys for the dma controller and bytes transferred mean anything. > It does mention in dmesg that it allocated dma channels for uart3 though. Then it should use it :) > How do you tell if it is using dma? There is omap_8250_tx_dma() and omap_8250_rx_dma(). Both setup callbacks (the rx+tx _complete). Upon successful DMA transfer you should see them invoked with bytes transfered (>0). For RX transfer you need at least trigger bytes in the FIFO within a given time frame (I think it was 46 bytes and the delay may be up to 2 bytes). If you miss this then DMA for RX won't wire and you purge the FIFO manually via "timeout-interrupt" (the callback will be invoked with an error condition and 0 bytes). Assuming this works for you then one should figure out why the counters in /sys are not updated… Sebastian -- To unsubscribe from this list: send the line "unsubscribe linux-serial" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
