Debug mipi interface

We’ve got out Xavier module connected to an FPGA that acts a a video mux on our system. For the selected video stream, it will be sent to the Xavier for video analytics processing over the MIPI interface. We’re starting testing with simple patterns in the frame buffer. Are there tools to read in the mipi and process it - ie. write it to a file for some simple analysis/comparision? We don’t have a video out on the Xavier.

hello larry.ciummo,

from hardware point-of-view, you may probe the MIPI signaling to check the high speed data.
once you’d confirmed there’s signaling sending to Xavier module, you may enable Applications Using V4L2 IOCTL Directly to check the functionality.

Thanks. That looks very useful. Unfortunately the Jetson AGX doesn’t want to power up when plugged into our system/camera. I’ll post something on that.

The V4L2 IOCTL app requires a driver for the camera interface - /dev/video in the example. Do I have to develop/install a driver to use the mipi interface? As I mentioned, there are multiple cameras coming into an FPGA and the video stream will be switched between them in the FPGA and the selected stream will be sent to the Xavier for analytics.

hello larry.ciummo,

yes, you’ll need to develop your own drivers to imitate it as camera drivers.
you should setup connections of your FPGA device sending MIPI signaling to the CSI port.
you may also refer to HDMI2CSI bridge driver, TC358840 for reference,
for example,

Thanks. The camera driver guide recommended the imx185.c for the direct to v4l2 interface. Is that one you referenced a better starting point for me to capture the stream with v4l2-ctl?
Larry @ FLIR

hello larry.ciummo,

IMX185.c were reference drivers for bayer sensor bring-up; you may check it for your device tree implementation.
it’s slightly different since you’re having FPGA device for sending MIPI signaling to CSI ports. that’s why I would suggest you should also check HDMI2CSI bridge driver, TC358840 for reference.

kernel sources,
device tree,

Thanks. Will take a look at it. I’ve almost got my dev env setup for module blds.