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!