TorizonCore Builder for Verdin iMX8MM - What overlay to use for LVDS -> HDMI display?

Technical Support
,
1

I have build the given tcbuild.yml to be used on a Verdin iMX8MM (no HDMI display), based on the same setup that works for my iMX8MP board:


# Documentation https://developer.toradex.com/torizon/os-customization/torizoncore-builder-workflow/#customizing-the-configuration-file
# Configuration file outline:
# ⚠️ Mouse hover to the properties to see documentation
# ⚠️ ctrl+space inside an object or property to get the autocompletion tips
input:
  easy-installer:
    toradex-feed:
      version: "7.1.0"
      release: quarterly
      machine: verdin-imx8mm
      distro: torizon
      variant: torizon-docker
      build-number: 4 

customization:
  splash-screen: my_splash_screen.png
  device-tree:
    include-dirs:
      - linux/include
      - linux/arch/arm64/boot/dts/freescale/
    custom: linux/arch/arm64/boot/dts/freescale/imx8mm-verdin-wifi-mallow.dts
    overlays:
      add:
      - device-trees/overlays/verdin-imx8mm_hdmi_overlay.dts **???? WHAT TO USE HERE ????**

output:
  easy-installer:
    local: my-os
 ostree:
    branch: my-os
    commit-subject: my-os

Naturally for iMX8MP I use the HDMI overlay (as shown in code) and the display works fine.

For iMX8MM, there is no HDMI board, so the device-trees/overlays/verdin-imx8mm_hdmi_overlay.dts seens to be useless.

Questions:

a) Should I use any overlay for the iMX8MM LVDS display, as we do for the iMX8MP ?

b) If yes, what would be the correct overlay to use? (my environment is a Toradex Verdin Development Board with LVDS to HDMI converter conencted to my display)

c) If not, shall I only delete that line and all goes through?

Thanks for helping.

2

Hi, I’m the Toradex AI Assistant. The Toradex Support team will follow up with you shortly!

Did you like my answer?

:+1: :-1:

Hello!

For your Verdin iMX8M Mini setup with an LVDS to HDMI converter, you will indeed need to use a device tree overlay. The appropriate overlay for this configuration is:

verdin-imx8mm_dsi-to-hdmi_overlay.dtbo

This overlay is specifically designed for the Verdin iMX8M Mini when using a DSI to HDMI adapter. It’s important to use this overlay to ensure proper display functionality, as the iMX8MM does not support native HDMI. Therefore, the verdin-imx8mm_hdmi_overlay.dts you currently have will not work for your setup.

Please make sure to apply this overlay starting from version 6.1.0 of Torizon OS. This will help ensure that your display setup functions correctly.

If you have any further questions or need additional assistance, feel free to ask.

Best regards,
Toradex AI Assistant

Please, also check if these links can help you solve your problem:

Device Tree Overlays on Toradex System on Modules | Toradex Developer Center.

3

Changed as recommended from Toradex AI:

tcbuild.yml:


# Documentation https://developer.toradex.com/torizon/os-customization/torizoncore-builder-workflow/#customizing-the-configuration-file
# Configuration file outline:
# ⚠️ Mouse hover to the properties to see documentation
# ⚠️ ctrl+space inside an object or property to get the autocompletion tips
input:
  easy-installer:
    toradex-feed:
      version: "7.1.0"
      release: quarterly
      machine: verdin-imx8mm
      distro: torizon
      variant: torizon-docker
      build-number: 4 

customization:
  splash-screen: my_splash_screen.png
  device-tree:
    include-dirs:
      - linux/include
      - linux/arch/arm64/boot/dts/freescale/
    custom: linux/arch/arm64/boot/dts/freescale/imx8mm-verdin-wifi-mallow.dts
    overlays:
      add:
      - device-trees/overlays/verdin-imx8mm_dsi-to-hdmi_overlay.dts 

output:
  easy-installer:
    local: my-os
 ostree:
    branch: my-os
    commit-subject: my-os

The splash screen still does not appear on boot. I got also a red led powered on the LVDS->HDMI converter board (BRIDGE RESET). Same behaviour.

4

Hi @renatom
There are a lot of things wrong here.

The verdin imx8m mini doesn’t have a native HDMI, so this overlay doesn’t exist.

You can check this information in the product page, but the LVDS is available using the DSI-LVDS adapter.

We don’t have an LVDS to HDMI converter.
If you mean the DSI to HDMI adapter, to use the DSI to HDMI adapter you need to use the DSI to HDMI overlay.

You can also check our page about setting up displays on Torizon to learn how to set up displays on Torizon.

Also, you mentioned using the Verdin development board, so why are you setting the Mallow DTS here?

5

Allan,

After a review on all comments, my current tcbuild.yml version:

# Documentation https://developer.toradex.com/torizon/os-customization/torizoncore-builder-workflow/#customizing-the-configuration-file
# Configuration file outline:
# ⚠️ Mouse hover to the properties to see documentation
# ⚠️ ctrl+space inside an object or property to get the autocompletion tips
input:
  easy-installer:
    toradex-feed:
      version: "7.1.0"
      release: quarterly
      machine: verdin-imx8mm
      distro: torizon
      variant: torizon-docker
      build-number: 4 

customization:
  splash-screen: my_splash_screen.png
  device-tree:
    include-dirs:
      - linux/include
      - linux/arch/arm64/boot/dts/freescale/
    custom: linux/arch/arm64/boot/dts/freescale/imx8mm-verdin-wifi-dev.dts
    overlays:
      add:
      - device-trees/overlays/verdin-imx8mm_dsi-to-hdmi_overlay.dts

output:
  easy-installer:
    local: my-os
#    bundle: 
#      compose-file: docker-compose.yml
  ostree:
    branch: my-os
    commit-subject: my-os

The splash screen still does not show up on boot…

I have a monitor connected on the DSI to HDMI adapter with the red led turned on.

6

hi @renatom

I just tested your tcbuild and the custom splash screen over the DSI-HDMI is working as expected.

Is it only the splash screen that is not working? Or you can’t get any video over the DSI-HDMI?
Can you test:

  • this tcbuild without the custom splash screen?
    • with this, you should be able to see the Torizon splash screen
  • run a weston demo, to check if the DSI-HDMI is properly working.