GUI displayed for TEZI version 5, but not for versions 6 and 7

bstubert · July 12, 2025, 2:12pm

My hardware consists of early 2nd generation Verdin products.

Model: Toradex 0058 Verdin iMX8M Plus Quad 4GB WB IT V1.0D
Carrier: Toradex Verdin Development Board V1.1B
Verdin DSI to HDMI Adapter Rev. 1.1

When I boot the image Toradex Easy Installer 7.2.0+build.5 on my Verdin iMX8MP, the TEZI GUI is never shown on the monitor connected via HDMI. I only see the following message on the monitor:

[    2.142415] imx_sec_dsim_drv 32e60000.mipi_dsi: [drm] *ERROR* modalias failure on /soc@0/bus@32c00000/mipi_dsi@32e60000/port@1

In the serial console, I can see some more messages:

U-Boot 2024.07-7.2.0+git.3f772959501c (Jul 01 2024 - 18:07:18 +0000)
...
Starting kernel ...

[    0.258179] rtc-ds1307 0-0032: hctosys: unable to read the hardware clock
Running /etc/rc.local...
Toradex Easy Installer 7.2.0+build.5 ()
Starting udev
[    1.379452] imx-bus-devfreq 32700000.interconnect: failed to fetch clk: -2
System time was Thu Jan  1 00:00:01 UTC 1970.
Setting the System Clock using the Hardware Clock as reference...
hwclock: RTC_RD_TIME: Invalid argument
System Clock set. System local time is now Thu Jan  1 00:00:01 UTC 1970.
Fri Mar  9 12:34:56 UTC 2018
Saving the System Clock time to the Hardware Clock...
Hardware Clock updated to Fri Mar  9 12:34:56 UTC 2018.
[    2.142415] imx_sec_dsim_drv 32e60000.mipi_dsi: [drm] *ERROR* modalias failure on /soc@0/bus@32c00000/mipi_dsi@32e60000/port@1

Welcome to the Toradex Easy Installer

When I boot the image Toradex Easy Installer 5.7.6+build.21, the TEZI image is properly shown on HDMI monitor.

When I install the image Toradex Embedded Linux Reference Multimedia Image 7.3.0-build.8 (built by Toradex) and run it on my board, the monitor stays black and the Qt application (cinematic application) is not shown. For the image Toradex Embedded Linux Reference Multimedia Image 5.7.6, the Qt application is displayed correctly.

So far, there was a pattern: Images with version 5.x.y are working, images with version 7.x.y are not working. The pattern doesn’t hold for the image Torizon OS Easy Pairing 7.2.0+build.13 (again pre-built by Toradex).

After I install the image Torizon OS Easy Pairing 7.2.0+build.13 on my board, it correctly displays the GUI for pairing the device with the Torizon Cloud. I could even deploy the application chromium-verdin-imx8mp on the board. After rebooting, Weston is shown and I can open a Wayland terminal. Chromium doesn’t seem to be available on the board. The error messages from booting the TEZI image 7.2.0 are present - plus some new. I guess the error messages aren’t that important.

Starting kernel ...

[    1.088859] rtc-ds1307 0-0032: hctosys: unable to read the hardware clock
Starting systemd-udevd version 255.17^
sysroot.readonly configuration value: 0 (fs writable: 1)
Using legacy ostree bind mount for /
[    6.818509] imx-bus-devfreq 32700000.interconnect: failed to fetch clk: -2
[    6.980072] fsl-aud2htx 30cb0000.aud2htx: failed to pcm register
[    7.002194] imx_sec_dsim_drv 32e60000.mipi_dsi: [drm] *ERROR* modalias failure on /soc@0/bus@32c00000/mipi_dsi@32e60000/port@1

What could be the reason for the described behaviour?

Is my hardware new enough for the 7.x.y BSPs? I’d like to get Qt applications with Weston on Torizon OS without buying new hardware.

Thanks, Burkhard

ToradexAI · July 12, 2025, 2:13pm

Hi, I’m the Toradex AI Assistant.

I might make mistakes. Our support team will step in if needed. If I answered your question, please tick the “Solution” checkbox. For follow-up questions to me, please use @ToradexAI in your post.

Did you like my answer?

Hello Burkhard,

Thank you for your detailed description and hardware information.

Your Verdin iMX8M Plus Quad 4GB WB IT V1.0D module, Verdin Development Board V1.1B, and Verdin DSI to HDMI Adapter Rev. 1.1 are all supported with Torizon OS and the 7.x.y BSP releases — you do not need new hardware for these capabilities (1)(2).

Explanation of Display Behavior

Working with 5.x.y images: These earlier BSP versions likely had a different default display setup or included the needed device tree changes by default.
Black screen on 7.x.y images: In Torizon OS and BSP 7.x.y, explicit device tree overlays are now required to configure external display adapters, such as the Verdin DSI to HDMI Adapter. Without the correct overlay, the display initialization fails, resulting in the modalias error and no output on HDMI (3)(4).
Torizon OS Easy Pairing 7.2.x works: This pre-built image likely enables the DSI-to-HDMI overlay by default or includes configuration for the demo GUI, which is why you see its output.

Solution: Enable the Required Device Tree Overlay

To resolve the black screen with the Toradex Easy Installer 7.x.y and Toradex Embedded Linux Reference Multimedia Image 7.x.y, you need to ensure the Verdin DSI to HDMI overlay is enabled:

Identify the correct overlay:
For the Verdin iMX8M Plus with DSI to HDMI Adapter, use:
- verdin-imx8mp_dsi-to-hdmi_overlay.dtbo
  This overlay configures the necessary interface for HDMI output via the adapter (3).
Apply the overlay:
- If using Torizon OS: Follow this guide to enable and deploy device tree overlays:
  Device Tree Overlays on Torizon
- For Toradex Easy Installer, overlays cannot be applied directly, but you can install Torizon OS or your chosen image with the overlay set, and then use that OS or image for your application.
- For the Toradex Embedded Linux Reference Images:
  See Setting Up Displays With Torizon for overlay setup.
Result:
With this overlay enabled, the HDMI output should function as expected, and Qt/Weston-based GUIs will display correctly.

Summary

Your hardware is fully supported for Torizon OS 7.x.y and display applications.
Explicitly enable the verdin-imx8mp_dsi-to-hdmi_overlay.dtbo overlay to get HDMI output.
You do not need to purchase new hardware for your use-case.

For running Qt applications with Weston on Torizon OS, proceed with overlay configuration and application deployment as described in the resources above (5).

Best regards,
Toradex AI Assistant.

bstubert · July 12, 2025, 2:26pm

The TEZI image 7.2.0 loads the following device tree overlays - including verdin-imx8mp_dsi-to-hdmi_overlay.dtbo and verdin-imx8mp_dsi-to-hdmi_overlay.dtbo. Still, displaying the TEZI GUI doesn’t work.

## Loading fdt from FIT Image at 44200000 ...
Using 'conf-verdin-imx8mp_hdmi_overlay.dtbo' configuration
Trying 'fdt-verdin-imx8mp_hdmi_overlay.dtbo' fdt subimage
    Description:  Flattened Device Tree blob
    Type:         Flat Device Tree
    Compression:  uncompressed
    Data Start:   0x44a390cc
    Data Size:    2219 Bytes = 2.2 KiB
    Architecture: AArch64
    Load Address: 0x50240000
    Hash algo:    sha256
    Hash value:   c4ec36638c7d6bff0af64735d0a5a71acf2a1041b7de69bca1dd1a1ca25b8112
Verifying Hash Integrity ... sha256+ OK
## Loading fdt from FIT Image at 44200000 ...
Using 'conf-verdin-imx8mp_dsi-to-hdmi_overlay.dtbo' configuration
Trying 'fdt-verdin-imx8mp_dsi-to-hdmi_overlay.dtbo' fdt subimage
    Description:  Flattened Device Tree blob
    Type:         Flat Device Tree
    Compression:  uncompressed
    Data Start:   0x44a35a1c
    Data Size:    4099 Bytes = 4 KiB
    Architecture: AArch64
    Load Address: 0x50240000
    Hash algo:    sha256
    Hash value:   3a33257cf0edb683c9719821ceb8375c56a2140aaa0da8da2a47b3998bfc03d3
Verifying Hash Integrity ... sha256+ OK
## Loading fdt from FIT Image at 44200000 ...
Using 'conf-verdin-imx8mp_spidev_overlay.dtbo' configuration
Trying 'fdt-verdin-imx8mp_spidev_overlay.dtbo' fdt subimage
    Description:  Flattened Device Tree blob
    Type:         Flat Device Tree
    Compression:  uncompressed
    Data Start:   0x44a42000
    Data Size:    561 Bytes = 561 Bytes
    Architecture: AArch64
    Load Address: 0x50240000
    Hash algo:    sha256
    Hash value:   a18be5d8a83083491c21b8de76d20e403b0ba28685fce6b628e196f46b1924d2
Verifying Hash Integrity ... sha256+ OK
Booting using the fdt blob at 0x50200000
Working FDT set to 50200000
Uncompressing Kernel Image to 48200000
Loading Device Tree to 00000000feab1000, end 00000000feac9bde ... OK
Working FDT set to feab1000

Starting kernel ...

The image Torizon OS Easy Pairing loads the same DTBO files with exactly the same sizes:

Applying Overlay: verdin-imx8mp_hdmi_overlay.dtbo
2219 bytes read in 3 ms (721.7 KiB/s)
Applying Overlay: verdin-imx8mp_dsi-to-hdmi_overlay.dtbo
4099 bytes read in 3 ms (1.3 MiB/s)
Applying Overlay: verdin-imx8mp_spidev_overlay.dtbo

Displaying a GUI works for Torizon OS Easy Pairing but not for the TEZI image - both are version 7.2.0. How do you explain that?

lucas_az.tx · July 14, 2025, 4:18pm

Hi @bstubert!

I’ve tested it and you’re right, it isn’t working as it should.

I talked to the R&D team and informed them about the bug. They will fix it as soon as possible.

Meanwhile, you can use a VNC viewer to see the TEZI and install an image. The VNC server is started, whether the display is working as expected or not.

Best regards.

bstubert · July 15, 2025, 11:22am

Hi Lucas,

Thank you very much for the quick response and the confirmation of the bug.

It doesn’t seem to be a problem for the TEZI image only, but also for the Multimedia Reference image. But I am sure you and your colleagues have this on your radar.

Thanks,
Burkhard