Re: Problem booting Orange Pi One on NetBSD 10.0_BETA

[Martin Husemann <martin%duskware.de@localhost>]

On Wed, Jul 26, 2023 at 10:16:55AM +0200, Hauke Fath wrote:
> > They only differ by the u-boot installed.
> 
> And they are all 32 bit arm systems, I take it.

Not sure I understand you correctly. There are 64bit images too.

> Is there a "from zero" text anywhere on how these systems boot, how to 
> set them up (beyond "armbsd has images"), what the sysutils/u-boot* 
> packages do (including the *.dts zoo), and how to make one? Whenever I 
> look at arm*, I feel like I am lacking essential knowledge to even 
> begin and ask questions.

The problem is that the low level booting is different per SoC.
If there is a pkgsrc u-boot pkg for a SoC it comes with machine readable
instructions for "installboot" to place the boot loader binary at the proper
place of the SD card image.

After that you are in u-boot and you load the binary device tree (dtb)
and the NetBSD kernel from a FAT partition, and then the NetBSD kernel
finds its root filesystem on a ffs partition (hopefully).

Overall straight forward, but little magic everywhere. Most magic is done
when you see u-boot run, the remaining parts is only some script selecting
the proper DTB file from the default u-boot environment.

Martin