Linux Ubuntu: Issues with enabling UART or SPI in DTS

Canonical Ubuntu Ubuntu OS issues
1

Hi,

We built a custom board based on the Rubik Pi 3 to use more peripherals (UART11 and SPI6).

To enable them, I cloned the Ubuntu kernel source, updated the DTS node configurations, and built combined-dtb.dtb.

However, after flashing the DTB, the system fails to boot. The error logs are attached below.

rubikpi-issue-uart11-cut.txt (3.6 KB)
rubikpi-issue-spi6-cut.txt (3.2 KB)

According to the TurboX UART and SPI Development Guides, this issue appears to be an “Identify TZ Configuration Issue.”

Since we don’t have a way to modify and build the TrustZone (TZ) firmware ourselves, could you please advise on how we can address or work around this problem?

Our FAE suggested posting this issue on this forum for further assistance.

Thank you.

2

Dear Thundercomm,

Is there any update for this issues ?
we need to use UART11 and SPI6 interface on the board.
Environment:
Board: Custom board based on Rubik Pi 3
OS: Canonical Ubuntu 24.04 (ubuntu-24.04-preinstalled-server-arm64+rubikpi3-20250926-145)
Kernel: 6.8.0-1055-qcom

We analyzed the Rubik Pi 3 devcfg.mbn and confirmed that it seems that UART11 (0xa8c000) and SPI6 (0xa98000) are not registered in qupv3_perms (permission = 0x00).

Request:
Could you please provide a modified Rubik Pi 3 devcfg.mbn with UART11 and SPI6 registered as Non-Secure on TrustZone?
-UART11 (0xa8c000)
-SPI6 (0xa98000)

We are an enterprise user.
Thanks

3

Dear customer,
TrustZone is private code, please leave your email if you need it.
Simultaneously use your local enterprise email to send your requirements to service@thundercomm.com We will contact you and discuss further issues.

4

Dear Kinkin,
Thank you for your response.
Email : Edmund@uniquest.co.kr
We have also sent our detailed request to service@thundercomm.com.
Thanks

5

I asked in another thread, but it would be very helpful to have a version with access controls disabled.