NetBSD booting from CD:
[sparc] Booting file 'cdrom' without parameters. Loading a.out image... Loaded 8388615 bytes entry point is 0x4000 Jumping to entry point... obmem:>> NetBSD/sparc Secondary Boot, Revision 1.15
(builds@b3.netbsd.org, Mon Dec 19 03:43:03 UTC 2005)
Booting diag Cannot load diag: error=20
device[sd(0,2,0):b] ("halt" to halt):
Interesting - it seems to be picking up the diag-file setting from OF - the name "diag" - perhaps because "diag-switch?" is set to true. That implies that the loader is making calls into OF and getting at least some stuff it likes.
In any case, it's now at the BSD device prompt, which is also good. You should be able to type in a BSD-style boot-spec here to disk, partition, and name of the kernel here. Unfortunately Sparc-to-BSD device mapping is a bit funky so you may have to grep through the BSD docs for details.
If you typed in "bsd" at the above prompt, it should try to load the file named "bsd" from the default device listed above in square brackets.
NetBSD kernel directly:
[sparc] Kernel already loaded OBP version 3, revision 2.25 (plugin rev 2) Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005 The NetBSD Foundation, Inc. All rights reserved. Copyright (c) 1982, 1986, 1989, 1991, 1993 The Regents of the University of California. All rights reserved.
NetBSD 3.0 (GENERIC) #0: Mon Dec 19 04:01:27 UTC 2005 builds@b3.netbsd.org:/home/builds/ab/netbsd-3-0-RELEASE/sparc/200512182024Z- obj/home/builds/ab/netbsd-3-0-RELEASE/src/sys/arch/sparc/compile/GENERIC total memory = 127 MB avail memory = 120 MB bootpath: data fault: pc=0xf02a4f3c addr=0x7ff000 sfsr=126<PERR=0,LVL=1,AT=1,FT=1,FAV,OW> panic: kernel fault halted
As a guess it's trying to print or create the "bootpath" and hit a bad or uninitialized pointer - 0x7ff000. It got the total and available memory, so at least that's good. Pity it halted instead of dropping into the BSD debugger - you could get a stack-trace then.
It may be trying to get args from the OF "boot" command, which should pass args to the loaded image. Perhaps it doesn't have any args, or perhaps they're bogus?