Re: MP support on SS20

[Romain Dolbeau <romain%dolbeau.org@localhost>]

Le mer. 24 févr. 2021 à 16:29, J Booth <166sunny%gmail.com@localhost> a écrit :
> Thanks for the response. I did an md5 on /netbsd (GENERIC.mp) and it
> was correct. I also checked that GENERIC from the same download
> location matched my old kernel - which it did. I have a single large
> root partition (14GB) and a swap partition. I remember reading
> something about not being able to boot on anything after 2GB. Perhaps
> the new kernel was stored not in the first 2GB. I’ll have to look into
> that limitation some more.

Yes, PROMs from that era cannot load files from beyond 2GiB after the
beginning of the drive.
You should use a <2 GiB root filesystem at the beginning of the drive,
then have the partition for swap and /usr, /home or whatever.

Alternatively, with a SCSI2SD V6 you can define multiple virtual SCSI
drives on the micro-sd card so you can have a virtual drive of <2 GiB
with the root and everything else on a different virtual drive.

As for SMP - I have run the NetBSD 9.0 (haven't updated to 9.1 yet)
SMP kernel in SPARCstation 20s with dual-SM61, dual-SM71, dual-SM512
(quad SuperSPARC!), quad-HyperSPARC (2x90 + 2x125) and even dual-SM100
for testing (so quad-SPARC v7! modules intended for the SS670MP, not
the SS20) with no issue. It just worked out-of-the-box.

The dual-SM61 setup is my testbed for
<https://github.com/rdolbeau/SBusFPGA>, all the crashes I had were my
own fault :-)

Cordially,

-- 
Romain Dolbeau