ARMv7 now has a bootloader

Progress on the armv7 platform continues, and Jonathan Gray writes in to the arm@ mailing list with some promising news:

There is now a bootloader for armv7 thanks to kettenis@ Recent armv7 snapshots will configure disks to use efiboot and install device tree dtb files on a fat partition at the start of the disk.

u-boot kernel images are no longer part of the release but can still be built for the time being. We are going to start assuming the kernel has been loaded with a dtb file to describe the hardware sometime soon. Those doing new installs can ignore the details but here they are.

Support for EFI payloads was introduced in u-boot 2016.05, a port was recently imported for u-boot along with a patch to prevent it from allocating memory from non-populated regions (required for non imx platforms). A dtb port with prebuilt dtb files was also added.

If BOOTARM.EFI is placed on fat or ext2 as /efi/boot/bootarm.efi and dtb files placed in /, /dtb/ or /dtb/current u-boot will automatically load and run it without any boot.scr or uenv.txt needed. efiboot will then load kernel images off ffs filesystems it finds. The u-boot binaries themselves on the same partition or raw offset remain largely board specific.

Thanks kettenis, jsg and the whole ARM crew for your work in getting OpenBSD to run on these devices.