I have been having trouble getting a current kernel to work with my PB180 
(in
other than serial console mode).  Of the kernels available, only two from 
Takashi's web page have worked for me -- the rest have not made it past 
the
single preserving symbols line.

With a patch provided by Allen Briggs, I have been able to build a kernel
based on the current sources that gets past the single preserving symbols 
line.
With a MRG_ADB kernel, I get as far as

mrg: '2nd Powerbook class ROMs' ROM glue, tracing off, debug off, silent 
traps
mrg: I/O map kludge for ROMs that use hardware addresses directly.
adb: bus subsystem

before the system hangs.  Without the MRG_ADB option, I get

NetBSD 1.2D (HD180) #0: Sat May  3 16:43:55 PDT 1997
    andy@myname.my.domain:/usr/src/sys/arch/mac68k/compile/HD180
Apple Macintosh PowerBook 180  (68030)
real mem = 12582912
avail mem = 9416704
using 179 buffers containing 733184 bytes of memory
mrg: '2nd Powerbook class ROMs' ROM glue, tracing off, debug off, silent 
traps
mrg: I/O map kludge for ROMs that use hardware addresses directly.
adb: using PowerBook 100-series hardware support
adb: cleanup: nothing returned
trap type 1, code = a64d, v= 20271df
kernel: Address error trap
pid = 0, pc = 00088834, ps = 2700, sfc = 0001, dfc = 0001
Registers:

(followed by the registers and a stack trace).  The keyboard does not 
respond at
the debugger prompt.

I'll continue to play around with it.

--Andy Fyfe
bandr@best.com