coreboot

Hi all!

I have a HP Elitebook 8470p with Libreboot 20240612 installed, but I've also tried compiling from scratch using the git head of coreboot.
I have been using it with Ubuntu 24.04, but there are some issues:
1.) Screen brightness can not be changed.
2.) After returning from sleep, the WWAN module (MC7710) is not accessible.
3.) Bluetooth is not recognized, as if the BT module was absent.

It may not be related, but Windows 10 fails to boot with "ACPI BIOS error" BSOD message.

I have actually found out the third problem: the device tree override (/src/mainboard/hp/snb_ivb_laptops/variants/8470p/overridetree.cb) contains incorrect values for usb_port_config. Enabling all USB ports fixes that issue, but I'm not sure if this is the correct fix.