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

Technical Support
, , ,
13

Thanks for your response.

Please remember to tick the “Solution” checkbox below if my response solves your question. If you have follow-up questions, just continue to tag me using @ToradexAI in your new posts.

Did you like my answer? :+1: :-1:

Hello! Thank you for your follow-up questions.

1. Which U-Boot variable contains the arguments passed to boot the Linux kernel?

The kernel boot arguments are assembled within U-Boot using environment variables—primarily setupargs and tdxargs.
The final boot arguments are typically contained in the bootargs variable, which gets passed to the kernel during boot.

  • setupargs includes console and basic settings.
  • tdxargs is intended for extra kernel parameters, such as your clk-imx8qx.m4_booted=1.

You can view the environment with:

printenv

Reference:
Best practices with U-Boot environment variables
U-Boot variables

2. How are kernel parameters typically passed in Toradex U-Boot?

When booting, the kernel command line is assembled, often something like:

setenv bootargs "${defargs} ${setupargs} ${vidargs} ${tdxargs} ${othervars}"

You need to ensure tdxargs is incorporated into this assembly, either in your custom boot script or the built-in logic.

3. Where can I find the default U-Boot environment for the Verdin iMX8MM?

The default U-Boot environment is compiled into U-Boot and can be found in the source code:

  • include/env_default.h
  • Board-specific settings: include/configs/verdin-imx8mm.h (for Verdin iMX8M Mini) or colibri-imx8x.h / apalis-imx8x.h for other variants.

Reference:
Best practices with U-Boot environment variables - Sources for U-Boot environment variables

Action Steps

  • In U-Boot, ensure your tdxargs is being used:

    1. Run printenv.
    2. Look at how bootargs is composed.
    3. If tdxargs is not part of bootargs, you may need to append it. For example:
      setenv bootargs "${bootargs} ${tdxargs}"
saveenv
    4. If using OSTree or TorizonCore, confirm the overlay configuration if you update environment variables from Linux.

  • Persist changes
    Always run saveenv to store your changes across boots.

Tip:
The fw_env.config file should, in most cases, point to the appropriate device for environment changes (for Torizon installations use /dev/mmcblk2boot0 -0x2200 0x2000).

Reference:
Community: U-Boot env vars

Summary:

  • bootargs is the main variable passed to the kernel.
  • setupargs and tdxargs are important components—tdxargs is specifically for extra kernel arguments you want to append.
  • The default environment is described in U-Boot source files as above.

If you need further help with your environment, feel free to paste your current printenv output for review.

Best regards,
Toradex AI Assistant.

Helpful links: