On Sat, 12 Feb 2000, Miles Nordin wrote:

> Seriously, there is a way to do this, but I don't think we should offer it
> to users as a favoured booting method any more.  The current instructions
> suggest booting from a suntar or dd-made floppy, but new machines don't
> even have floppies--it might be good to avoid confusion by not focusing on
> floppies at all.  There is a way to boot off an HFS volume, isn't there?

HFS booting works with -current. The big problem is getting a file which
OF will load. ofwboot.xcf is one such thing.

> One thing I'd like to see is a list of Macintosh models and what their
> OpenFirmware is/isn't capable of doing.  Some have framebuffer support,
> some are serial only.  Some can boot off [XXX media, XXX partition table,
> XXX filesystem], others can't. Some can boot ELF, some require COFF.

Oh, here's a start. there are 5 classes of machines:

No OF:	6100, 7100, 8100, ...

OF 1.0.5:	7500, 7600, 8500, 9500, ...

OF 2.0.:	Original Beige G3

OF 2.4:		Newer Beige G3's, ...

OF 3.X:		iMacs, Blue G3, G4, ...

Most of the OF syntax changed from major version to major version.
The differenfce between the OF 2.X versions is that 2.4 won't boot
installboot partitions while 2.0.something (I have one at home) will.

> Maybe if we make a unified list of OpenFirmware Boot Commands for
> {SCSI,IDE}{ZIP's,hard disks,CD-ROM's}, floppys, HFS volumes, people can
> try them out and slowly report in what works.  I have a feeling after we
> do this, we'll be able to offer almost all Mac users a better option than
> the floppy, but I may be wrong.

I think this is a good idea. :-)

> >     - how to boot from the network
> 
> boot enet:0

As mentioned elsewhere, it's boot enet for older firmware.

> >     - how to get the firmrware input/output from the screen
> 
> Not all firmware can use the screen.

Actually they can. You just need to bash on OF a bit. The linuxppc folks
have a lot of stuff here we should look at.

Older models need to have the screen refered to by name, not "screen".
Like /chaos/control or some such. Also, my 8500 needed some OF mumbo jumbo
typed in to get the screen working. Basically OF didn't give the screen
enough time to settle. Adding delays and some other glue, and it works.

> It is possible to boot kernels directly over TFTP without using
> ofwboot.elf, but this is foolish because:
>  o ofwboot gives you another opportunity to type things at a boot prompt
>  o ofwboot can boot gzip'ed kernels if you want to
>  o all the other ``real'' computers use a second-stage loader, and you
>    want to use your Mac like a ``real'' computer, don't you? :)
>  o you should boot /netbsd off your real root filesystem, because it's
>    important that the kernel you just finished booting be available to
>    userland kvm-grovelers.
>  o Upgrading /netbsd on the running box is intuitive, while upgrading
>    /usr/export/tftpboot/netbsd-MAC46472-A on the NFS server is not
>    intuitive.

Another reason: ofwboot can preserve the kernel symbol table, which direct
booting from OF will not do. 

> ofwboot.elf is an ELF object, and ofwboot.xcf is COFF.  ofwboot.xcf is not
> part of the distribution set, but it is buildable by hand in
> src/sys/arch/macppc/stand and will hopefully be included in the
> distribution soon.  

It should be in -current distributions, I thought.

> If you have an older Mac that can only boot COFF files, use ofwboot.xcf.  
> You wi ll know your Mac is old because when you try to boot ofwboot.elf it
> will give you a cryptic error in all-caps something like:

We can shorten this to be: OF versions 1 & 2 only support XCOFF. Only
version 3 supports ELF.

Take care,

Bill