uboot and bsd on BeagleBone Black

[Sulev-Madis Silber (ketas)]

Hello :)


On 2014-12-26 05:40, eros.wade wrote:
> I've succeed complied uboot and freebsd on BeagleBone Black with crochet.
> But I don't know how bsd can run on beaglebone black.

Well, crochet should create image, which you can use by dd'ing it into
SD card.


> I know that uboot for BBB contains thouse hardware info (PINS, GPIO, SPI etc).
> How can bsd get thouse infos from uboot.
> Or uboot just load BSD, but where is the hardware infos on bsd src tree?

This method, called Flattened Device Tree (FDT) can be used in multiple
different ways. I don't know if FDT can be built statically into U-Boot.
We don't use it that way. Previously FDT DTB (Device Tree Blob) was
loaded by U-Boot, and it's memory address was given to ubldr (U-Boot
loader(8)). Now, uboot just sets fdt_file for loader(8) to load. This
file is in UFS filesystem, normally under /boot/dtb. It's also known
issue that boot fails when DTB in /boot/dtb and you don't use
/boot/loader.rc which disables Forth in loader(8) (which also removes
whole 21s from boot time).

Crochet has become outdated lately. And people, including me, don't use
it to make their images. Especially if you don't like constant image
making and like to upgrade device over network. Or maybe even boot over
network. Those are all very specific setups and doesn't exactly fit into
end-user-image-maker that crochet seems to be.

The problem is that it might be too difficult for you. If it's not, I
could explain how you could get better system built for your BBB.
Or you could browse around under http://ketas.si.pri.ee/bbb/

And correct U-Boot for BBB is now in ports, under sysutils/u-boot-beaglebone

I kind of wish I don't need to explain all those things repeatedly to
people. Maybe I should fix crochet just because of that.

You could also read board/BeagleBone/README inside crochet tree.