Hi all, > Is it loaded with this DTB or does it rely on ACPI? It is loaded with this DT (booted from grub with efifb enabled in kernel config) The uefi is just Lumia950XLPKg (link : [1]) with some modifications. It also contains code from SurfaceDuoPkg (link : [2]) that resets the platform, and uefi then reinitializes MMU (with a more windows-suited memory map). I'm guessing it could be the reason for the difference in behaviour. Kind regards, Dominik [1] https://github.com/WOA-Project/Lumia950XLPkg [2] https://github.com/WOA-Project/SurfaceDuoPkg