Troubleshooting Xavier C-PHY Port Configuration for Receiving C-PHY from Generator Connected to Camera Connector J509

Robotics & Edge Computing Jetson & Embedded Systems Jetson AGX Xavier
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cphy
cphy1465×743 42.9 KB

We are trying to configure the Xavier C-PHY port to receive C-PHY from a C-PHY generator connected to the AGX-Xavier camera connector J509. We have measured the C-PHY signal output using an oscilloscope and verified the presence of data output.

To test the configuration, we have generated a C-PHY image using a generator and created a “dummy” driver from an imx Sony sensor (which bypasses the i2c configuration).
In the device tree, we have modified/set the following fields:
bus-width = <3>,
num_lanes = “3”, and
phy_mode = “CPHY”.
However, when running argus_camera, we are not getting any data.

FWIW I am using jetpack-4.6

We would like to know the possible causes for this issue and any other steps we should take, such as specific commands to execute or logs to check.

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hello moshe.arad,

please also refer to Topic 241898 and apply kernel patch to configure CPHY mode by device tree instead of hardcode values.

so, is the port binding correct? are you now able to register video node to linux kernel?
please try to verify the port binding result, as following. $ sudo media-ctl -p -d /dev/media0
please share capture pipeline you’re using, you may also share the kernel logs for reference,
thanks

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Thanks , I have applied the changes , though I guess my problem is that it does not even get there as nothing is working.
I am adding here

  1. media-ctl output (as requsted).
  2. dmesg log
  3. dtsi changes I have made.

Technically I took a device tree which uses DPHY with 4 lanes (which is working and shows image on screen) changed

  • From DPHY to CPHY
  • Bus-width and num_lanes value from 4 to 3

we saw signals (using a scope) on the lanes.
We ran argus_camera and saw nothing (and log promos “no reply from camera processor”)

cphy.dtsi (2.8 KB)
dmesg_log.txt (19.9 KB)

media.txt (1.0 KB)

an insights ? ideas ? what todo next ?

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hello moshe.arad,

please try using V4L2 IOCTL to narrow down the issue, because it’s sometime more challenge to enable camera stream via Argus pipeline.
for example,
$ v4l2-ctl -d /dev/video0 --set-fmt-video=width=3840,height=1928,pixelformat=RG12 --set-ctrl bypass_mode=0 --stream-mmap --stream-count=100

regarding to your attach logs, I saw there’s i2c timeout from 0x28, could you please confirm that’s nothing to do with the camera?

also, it looks you connected camera to CSI directly, do you still need virtual channel?
you’ve another camera node, imx324_csi_out1 that’s using CSI-A also, please also disable this node for testing.

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