Have just managed to boot a pocket beagle on arch!
Hardware: http://beagleboard.org/pocket
It basically boots on the am33x image, but some changes needed.
First uboot needs this patch added: https://lists.denx.de/pipermail/u-boot/2018-March/322188.html. The patch is already upstream on uboot, don't know if it will come out on 2018-03 uboot; but if not it should be in the one after.
This means that uboot recognises the name the board has in flash (A335PBGL), and then automatically selects the pocket beagle device tree. The current device tree for the pocket beagle is one that Robert Nelson did, its not mainline but is in the arch image. Now I'd expect there to quickly be a mainline device tree, Roberts device trees are huge:
$this->bbcode_second_pass_code('', '-rw-r--r-- 1 root root 56866 Mar 7 02:13 am335x-boneblack.dtb
-rw-r--r-- 1 root root 121484 Mar 7 02:13 am335x-pocketbeagle.dtb')
So when the kernel tree has a working device tree, I guess we should switch to that.
Next problem, out of the box, the PocketBeagle only has the usb-otg connection enabled, so there is no ethernet port mounted on the board. This means that the default image should bring up usb gadgets, I've configured so that both a usb serial connection and an ethernet connection come up using libcomposite. This isn't the nicest interface but it works.
My gut feeling, we should make this change to the default am33x tree, e.g. it would be better on the beagle bone black if the usb connections came up be default. For the black this isn't essential, but is nice; for the pocket its essential.
I'll give details below of the changes I made in detail. Can we add the Pocket Beagle to the boards supported?