How to fix IPU warning

[skappen]

We are using a custom driver for capturing video (1280x722 YUV 422 @ 30fps) from two digital imagers on iMX6Q based custom board in freescale linux 3.10.17 kernel. One imager is connected to CSI0 port of first IPU and other connected to CSI1 port of second IPU. We are able to capture and verify the captured images. We are seeing the below ipu error interrupts  when multiple interrupts occur simultaneously in the system. For eg if we insert a usb disk to the system we are seeing  one or two IPU warnings for each insertion. I suspect this could be due to interrupt latency if so is there is any way to increase ipu interrupt priority? or any other method to avoid this frame lost situation?

IPU Warning - IPU_INT_STAT_10 = 0x00000002

IPU Warning - IPU_INT_STAT_10 = 0x00000001

[felixwei]

Hi Sam,

I met the same issue, would you like to share how to fix it ?

[skappen · Accepted solution]

The double buffer approach in IPU resolved the issue. In this scheme two buffers are initialized using the API ipu_init_channel_buffer() and kept ready for receiving frames.

[Yuri]

  Please look at the following :

Re: imx-ipuv3 imx-ipuv3.0: IPU Warning - IPU_INT_STAT_10 = 0x00000001

Have a great day,
Yuri

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[skappen]

Thanks Yuri , I already gone through the links provided.  I am not getting continuous IPU Warning. The  IPU Warning - IPU_INT_STAT_10 = 0x00000001 seems to occur during time where multiple interrupts need to be serviced. IPU error interrupts frequency is around two/hour.    

[Yuri]

Perhaps the system is heavy loaded in Your case : VPU coding / encoding, USB, Ethernet

transfers, file storage. You may try to decrease system load.

Regards,

Yuri.