Booting arguments for NetBSD under qemu

[Torbjorn Granlund <tg%gmplib.org@localhost>]

For good reasons (a course I give at KTH) I need to boot NetBSD sparc32
under qemu.

Recent NetBSD sparc32 releases do not cooperate well with qemu.
Therefore I use 5.2.  I do not depend on the latest and greatest release
for the present use.

Installation goes like a charm, using this (slightly shortened) command:

  qemu-system-sparc -m 256 -hda disk.img -cdrom sparccd-5.2.2.iso \
     -boot d -nographic

Ideally, 

  qemu-system-sparc -m 256 -hda disk.img -nographic

would boot the installed system, but alas, it does not.

Instead, an explicit kernel argument is needed as in,

  qemu-system-sparc -m 256 -hda disk.img -kernel netbsd-GENERIC
    -nographic

where NetBSD-5.2.2/sparc/binary/kernel/netbsd-GENERIC.gz was used for
the kernel argument.

Unfortunately, this kernel asks for root device, dump device, and a few
more things.  This makes automated booting hard.

I have tried hard to find how to pass suitable arguments to the kernel
from qemu, but have not come very far.

Specifically, I have not been able to find documentation of the possible
command line argument of netbsd-GENERIC.  I have not found the place in
the kernel sources where kernel command line arguments are handled.

Please help with some advice.


Torbjörn