"imx-uart 21f0000.serial: overwrite!" errors on i.MX6 board

[sethrichards2]

Our device uses an internal UART on the i.MX6 chip to communicate with a peripheral chip. We're running the 3.10 Linux kernel from Freescale. We occasionally see "imx-uart 21f0000.serial: overwrite!" errors on this UART, and we have occasional problems communicating with this peripheral. This appears to be a DMA overrun error on the UART, and when I comment out DMA support for this UART, I see occasional "Rx FIFO overrun" errors on this channel. Does anyone have any experience with what might cause these errors? Thanks.

[igorpadykov]

Hi Seth

this is caused by processor internal buses bandwidth limitation,

one can try to decrease bus traffic by reducing number of running

applications, increasing processor/memory speeds or reducing uart baudrate.

Best regards

igor