Folks,

I've just finished updating the pmax bootblocks to something based on
the current Alpha bootblocks that Chris Demetriou has done a lot of work
on over the last few months.  The key driver for this work was native
CD9660 (and LFS) support in the bootblocks - it is now possible to load
a pmax kernel directly off a ISO filesystem.

One major change is that we now use installboot(8) to install the
bootblocks instead of "disklabel -B".  To install the new first stage
bootblocks on a disk, use the following commands (which X is the SCSI
ID of the disk):
	# disklabel -W rzX
	# /usr/mdec/installboot /dev/rrzXc /usr/mdec/bootxx_ffs
Hopefully the need for the "disklabel -W" will disappear soon.

The second stage bootblock is now called "/boot.pmax" instead of
"/boot" - this allows co-existance on boot filesystems with other
architecture's bootblocks to facilitate multi-system boot CDs.  The
first stage bootblocks will look for "/boot" if "/boot.pmax" isn't
found for backwards compatibility.

I've put a copy of the new bootblocks on ftp.netbsd.org in
pub/NetBSD/arch/pmax/bootblocks/bb19991128.tar.gz .  Extract this
from your root directory, then install the new first stage bootblocks
using installboot(8) as described above.  You can remove /boot,
/usr/mdec/boot, /usr/mdec/rzboot and /usr/mdec/bootrz after this - these
files aren't used any more.

There is an updated man page for boot(8) and a new man page for
installboot(8) - installboot(8) has some examples on how to build a
bootable ISO CD.  I'm still updating distrib/pmax, so building install
media doesn't work at the moment.  Please ask here or send-pr any
problems or questions you have with the new bootblocks.

Many thanks to Philip Tait who wasted more than one blank CD testing
ISO support for me.

Simon.