On Fri, 5 Oct 2001, Antti Kantee wrote:

> On Fri Oct 05 2001 at 13:43:18 +0300, Petri Tapio Koistinen wrote:
> > So ARCS can't boot FFS? How about porting XFS to NetBSD? Couldn't be that
> > hard (tm). That would make life... erm... this thing much easier. ;-)
>
> As explained (and confirmed working!) very recently in a posting by
> Rafal to this list, you can place the kernel in the disk volume header
> (dvh) and boot happily from there. No need for XFS support in NetBSD.
>
> Wouldn't mind xfs support though, but I'd like it for interoperability
> reasons (think ext2).

It can be done.  In fact it has been done in the -mipsco port already,
and it should be a matter of taking the code and making a few changes to
call the correct Arcs functions, and you are mostly there.

This will use the standard NetBSD 2-stage bootloader.  The first stage
bootloader lives in the mips dvh volume header (which can also be the
first 16 blocks of a UFS filesystem), which knows enough to find the 2nd
stage boot loader off a UFS partition... Then NetBSD boots...

The -pmax port uses a similar scheme (in fact that is what the mipsco
implementation was based on) as it also has a "arcs" style library in
firmware.

The installabel utility in the -mipsco port will DTRT with the volume
headers.  There is also a sysinstall build for -mipsco that correctly
installs NetBSD and the correct boot blocks etc.

When I get time I plan on implementing the above for sgimips, but it will
be a month or two before I can start.  If someone wants to jump ahead and
start doing this let us know!

Presently I am doing a major re-write of the WD33C93 SCSI driver to
correctly support SYNC modes, better scsipi layer support (both done) and
implement SCSI TAGS.

-- 
Wayne Knowles			NetBSD/mipsco port maintainer
wdk@netbsd.org			http://www.netbsd.org