/dev/ttyRPMSG30 not created in Torizon OS 7 on Colibri iMX8QXP

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Hello, and thank you for providing the output.

You are correct: your kernel command line shows clk-imx8qx.m4_booted=1 is being passed correctly, so kernel-side clock dependencies should not be blocking RPMsg. This points to another problem preventing the driver from progressing past the “deferred probe pending” state.

Here’s what you should check next:

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1. Check M4 Firmware Output

• You mentioned seeing rpmsg_lite starting remote link… on UARTB.
• In a working setup, the M4 firmware should also print Link is up! and Nameservice announce sent.
• If you do NOT see these extra messages, your M4 firmware may not be completing RPMsg initialization. (This is a common cause for the Linux rpmsg driver to keep deferring.)

Reference:

RPMSG on a Toradex Apalis iMX8

Dear Toradex Community, I am building an application with a Apalis iMX8 on which both the M4Fs communicate with a separate CAN Bus to our product. On those I use FreeRTOS and they communicate with each other using the Message Unit. Now I would like to also broadcast the received CAN Data from both of the M4Fs to the Linux-System. For this purpose I try to use RPMSG. I tried to follow the readme.txt in the rpmsg_lite_str_echo_rtos example in the multicore folder of the SDK from NXP and you…

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2. Verify Device Tree Status in Linux

• Confirm your overlay is applied (already done, as shown in dmesg).
• Confirm the reserved memory regions: dmesg shows vdevbuffer reserved at 0x90000000.
• Do you see virtio_rpmsg_bus virtio0: rpmsg host is online in dmesg?
  This should appear when Linux successfully connects to the M4 endpoint.

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3. Firmware Loaded and Running

• When loading from U-Boot, make sure your M4 firmware is loaded to the correct address and is running before Linux boots.
• It’s important that the firmware is not “stuck” or waiting for something that never happens—test with known-good reference firmware from NXP or Toradex if possible.
• The firmware must finish its initialization, create the endpoint, and be ready for communication before Linux tries to bind the rpmsg device.

Reference:

RPMsg device nodes not appearing in /dev after booting M7 and loading imx_rpmsg_tty on Verdin iMX8MP

Hello Team, I’m working on enabling communication between Cortex-M7 and Cortex-A53 cores on the Verdin iMX8MP module using RPMsg. Setup: Booting M7 core via U-Boot using the following commands:(SD_BOOT) setenv load_cmd “ext4load mmc 1:2” setenv cm_image “/home/rpmsg_lite_pingpong_rtos_linux_remote.bin” setenv cm_isize 20000 setenv load_cm_image “${load_cmd} ${loadaddr} ${cm_image}” setenv cm_boot “${load_cm_image}; cp.b ${loadaddr} 0x7e0000 ${cm_isize}; dcache flush; mw.w 0x550ff000 0 64…

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4. Linux Driver Status

• After running sudo modprobe imx_rpmsg_tty, check for new dmesg lines (dmesg | grep -i virtio).
• Look for messages about virtio_rpmsg_bus. Absence typically means the remote endpoint (from M4) is not visible to Linux.

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Summary & Next Steps

• If you only see the M4 message rpmsg_lite starting remote link… and not “Link is up!” or “Nameservice announce sent.” then the M4 isn’t fully initializing the RPMsg link.
• If dmesg never shows virtio_rpmsg_bus, it also indicates the host could not establish the link with the remote.
• Please confirm:
  • The exact full output on UARTB from your M4 at boot.
  • The output of dmesg | grep -i virtio after modprobing imx_rpmsg_tty.

This will make it easier to determine if it’s an issue on the M4 firmware side or Linux.

Best regards,
Toradex AI Assistant.

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Relevant links:

• RPMSG on a Toradex Apalis iMX8
• RPMsg device nodes not appearing in /dev after booting M7 and loading imx_rpmsg_tty on Verdin iMX8MP