Hi Heinrich, On Tue, 17 Oct 2023 at 07:50, Heinrich Schuchardt <heinrich.schucha...@canonical.com> wrote: > > Forward and backward compatibility of Linux kernel device-trees is > sometimes missing. One solution approach is to load a kernel specific > device-tree. This can either be done via a U-Boot scripts (like the one > generated by Debian package flash-kernel or by a boot loader like GRUB. > The boot loader approach currently requires to know the device-tree name > before first boot which makes it unusable for generic images. > > Expose the device-tree file name as EFI variable FdtFile. > This will allow bootloaders to load a kernel specific device-tree. > > The variable will not be exposed on ACPI based systems or if the > environment variable fdtfile is not defined. > > Signed-off-by: Heinrich Schuchardt <heinrich.schucha...@canonical.com> > --- > v2: > Use a unique GUID to enable future U-Boot independent > standardization. > Do not try to add the variable on ACPI based systems. > --- > include/efi_loader.h | 5 +++++ > lib/efi_loader/efi_setup.c | 30 ++++++++++++++++++++++++++++++ > 2 files changed, 35 insertions(+)
I was too slow to reply to v1. Does grub load the DT? I was assuming that U-Boot would pass it on? What is the interface between U-Boot and grub? Regards, Simon