AnsweredAssumed Answered

imx6 SPI in DMA mode sometime throws "I/O Error in DMA RX"

Question asked by Max Herman on Jan 21, 2015
Latest reply on Mar 16, 2015 by Daniel Morgan



I'm using IMX6 Dual Cote, it runs linux 3.18, all drivers are stock. Application I created continuously pushes lots of data on the SPI bus (4kB blocks, every 20msec).

And everything seems to be working most of the time. However once every 10-60 minutes I'm getting message: "I/O Error in DMA RX".


This message issued by spi-imx, because it doesn't get a callback from the RX DMA channel. I traced the problem back to the imx-sdma.c driver, and figured that DMA interrupt is not being called with the RX Interrupt Flag set for the appropriate channel.


I tried running SPI at 5Mhz and 30Mhz, this did not effect frequency of the "I/O Error in DMA RX" messages.


Anyone experienced such issued in the past?

Any suggestion what it can be/what next shall I try to debug it?

Anyone runs continuous SPI communication with 3.18 kernel?


I would really appreciate any help!


Thank you!