Re: NetBSD evbarm - Help with Raspberry Pi 4 installation and build

[John Klos <john%ziaspace.com@localhost>]

Hello,

> Thank you for the background on BOT vs UASP; that's not something I was 
> aware of. Nonetheless, I have found disk IO performance to be more than 
> adequate using an inexpensive Toshiba 120GB USB 3.0 external SSD -- 
> certainly orders of magnitude faster than an SD card on a Raspberry PI 
> 3B using an SD card.

There's so much to learn! I've learned things following this email thread.

> Unfortunately I have not made any further progress with getting the 
> arm64.img to successfully boot on the RPi 4 and fear I may have reached 
> the limits of my knowledge around UEFI, boot configuration, kernel 
> parameter, DTBs etc. I had hoped that the Rpi 4 would work "out of the 
> box", given that it is so prolific and NetBSD appeared to work well on 
> the RPi3, which as I understand has a very similar processor 
> architecture.

For me, I've found it easiest to start with an image made by Jun Ebihara:

http://mail-index.netbsd.org/port-arm/2021/04/15/msg007218.html

If you prepare a USB disk with aarch64 userland, then all you need to do 
to boot NetBSD with the USB disk as root:

Create boot.cfg on the MS-DOS partition on the SD card. Here's an example:

menu=Boot normally:rndseed /var/db/entropy-file;boot netbsd root=NAME=rpiraidroot
menu=Boot single user:rndseed /var/db/entropy-file;boot netbsd root=NAME=rpiraidroot -s
menu=Drop to boot prompt:prompt
default=1
timeout=10

I'm using a gpt wedge named rpiraidroot for the boot filesystem. You can 
change that to "root=sd0a" for a traditional disklabel-based filesystem.

Then just put netbsd created from GENERIC64 on the NetBSD ffs partition on 
the SD card.

Of course, fstab, rc.conf, et cetera, on the USB disk should be 
configured, but hopefully this'll get you started.

John