This reduce the per-board arm_install_uboot to just install u-boot.
While here remove the installation of rpi.dtb and rpi2.dtb as we load
them from the UFS partition via ubldr.
Reviewed by: gjb, imp (older version)
MFC after: 3 days
Differential Revision: https://reviews.freebsd.org/D16239
boot1.efi have some trouble to read MBR partitions, it needs them to be
aligned a certain way while loader.efi can cope with them either way.
We want to switch to loader.efi as the main efi loader everywhere, it seems
that arm64 using MBR partition will be the guinea pig.
Tested On: RPI3, Pine64
Reviewed by: imp
Approved by: gjb
The Pine64 root filesystem was incorrectly created directly on the MBR
partition. This can cause the loader to get confused when loading the
kernel from this filesystem.
The loader will see this as a small partition meaning later checks to
ensure it doesn't read past the end of the disk incorrectly report a
failure. This seems to work mostly by accident with the released images as
they are smaller than the reported size, however after growfs has run the
image may no longer boot.
Reviewed by: gjb, emaste, imp
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D14343
