Wednesday, August 3, 2022

[fedora-arm] device tree on Pi4B

I have a Pi4B that is working pretty well with the aarch64 version of Fedora Rawhide, but I have one issue that I haven't been able to find a solution to.

I have an Adafruit RTC connected via I2C (https://www.adafruit.com/product/3386). If I use the kernel device tree, this device is not found.

I then tried switching to the firmware device tree via the instructions in https://fedoraproject.org/wiki/Architectures/ARM/Raspberry_Pi/HATs. That works pretty well - I can now add an overlay for the RTC in /boot/efi/config.txt and the RTC is found during boot. dtoverlay=i2c-rtc,pcf8523,addr=0x68

However, once I've switched to the firmware device tree, I no longer have /dev/vchiq, which means that I can no longer use vcgencmd. Instead, vcgencmd gives me "VCHI initialization failed".

Is there any way to get both the RTC and vcgencmd to work? Which device tree would I choose? Do I have to build a custom kernel or is there some other way to enable the RTC with the kernel device tree?

Steve
_______________________________________________
arm mailing list -- arm@lists.fedoraproject.org
To unsubscribe send an email to arm-leave@lists.fedoraproject.org
Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/
List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines
List Archives: https://lists.fedoraproject.org/archives/list/arm@lists.fedoraproject.org
Do not reply to spam, report it: https://pagure.io/fedora-infrastructure/new_issue

No comments:

Post a Comment