Excerpts from internet.computing.netbsd.port-sparc64: 5-Nov-101 Re: 420R
fails to boot by Kenny Root@the-b.org 
> 23a00 
> hostname: netbsdtest
> domainname: xxx.com
> root server: install1
> root directory: /install/netbsd/NetBSD-1.5.2/sparc64/root
I still think that these messages are coming from inetboot, not the
prom. (among other things 0x23a00 bytes is too large to be ofwboot.net)

This is what my U60 gets when I boot it:

ok  boot net:xx.xx.xx.xx,ofwboot.net netbsd.gz -s         
Boot device: /pci@1f,4000/network@1,1:xx.xx.xx.xx,ofwboot.net  File and
args: netbsd.gz -s                                                      
             15400 >> NetBSD/sparc64 OpenFirmware Boot, Revision        
                    >> (mrg@powerofseven.eterna.com.au, Wed Aug 22
07:29:37 EST 2001)               Using BOOTPARAMS protocol: ip address:
128.2.120.219, hostname: BASILISK.ANDREW.CMU.EDU                        
                                root addr=xx.xx.xx.xx path=/usr0/nbsd
loadfile: reading header
elf64_exec: Booting /pci@1f,4000/network@1,1:xx.xx.xx.xx,ofwboot.net/netbsd.gz
4531544@0x1000000+6292640@0x1800000Fast Data Access MMU Miss
ok .trap-registers
%TL:1 %TT:68 %TPC:806bfc %TnPC:806c00
%TSTATE:1100000601  %CWP:1
   %PSTATE:6 AG:0 IE:1 PRIV:1 AM:0 PEF:0 RED:0 MM:0 TLE:0 CLE:0 MG:0 IG:0
   %ASI:0  %CCR:11  XCC:nzvC   ICC:nzvC

(the remaining TPC's are f000 adresses)

A non-netboot gets somewhat farther:
ok boot disk:b netbsd -s
Boot device: /pci@1f,4000/scsi@3/disk@0,0:b  File and args: netbsd -s
NetBSD IEEE 1275 Bootblock
..>> NetBSD/sparc64 OpenFirmware Boot, Revision 1.4
>> (mrg@powerofseven.eterna.com.au, Wed Aug 22 07:27:23 EST 2001)
loadfile: reading header
elf64_exec: Booting /pci@1f,4000/scsi@3/disk@0,0:b/netbsd
4516312@0x1000000+148632@0x1800000+4045672@0x1824498
symbols @ 0xfef90300 74+298728+157356 start=0x1000000
chain: calling OF_chain(800000, ee10, 1000000, fff83a80, 18)
[ using 456936 bytes of netbsd ELF symbol table ]
pmap_bootstrap: could not claim physical dseg extension at a6ca0000
size 360000
Setting DTLB entry 00000000 01000000 data e0000000 a7400074
Setting DTLB entry 00000000 01800000 data e0000000 a6400076
Setting ITLB entry 00000000 01000000 data e0000000 a7400074
Setting CPUINFO mappings...
Setting TSB pointer 00000000 018b0000
consinit()
setting up stdin

SIR Reset

Watchdog Reset
Externally Initiated Reset

And in case these trap registers are useful:
%TL:1 %TT:1ff %TPC:0 %TnPC:0
%TSTATE:0  %CWP:0
   %PSTATE:0 AG:0 IE:0 PRIV:0 AM:0 PEF:0 RED:0 MM:0 TLE:0 CLE:0 MG:0 IG:0
   %ASI:0  %CCR:0  XCC:nzvc   ICC:nzvc

%TL:2 %TT:68 %TPC:f000a15c %TnPC:f000a160
%TSTATE:4482000402  %CWP:2
   %PSTATE:4 AG:0 IE:0 PRIV:1 AM:0 PEF:0 RED:0 MM:0 TLE:0 CLE:0 MG:0 IG:0
   %ASI:82  %CCR:44  XCC:nZvc   ICC:nZvc

%TL:3 %TT:32 %TPC:1008590 %TnPC:10085a0
%TSTATE:4482041402  %CWP:2
   %PSTATE:414 AG:0 IE:0 PRIV:1 AM:0 PEF:1 RED:0 MM:0 TLE:0 CLE:0
   MG:1 IG:0
   %ASI:82  %CCR:44  XCC:nZvc   ICC:nZvc

%TL:4 %TT:4 %TPC:100867c %TnPC:1008680
%TSTATE:4482001502  %CWP:2
   %PSTATE:15 AG:1 IE:0 PRIV:1 AM:0 PEF:1 RED:0 MM:0 TLE:0 CLE:0 MG:0 IG:0
   %ASI:82  %CCR:44  XCC:nZvc   ICC:nZvc

%TL:5 %TT:3 %TPC:fffffffff0002098 %TnPC:fffffffff0002098
%TSTATE:4415003500  %CWP:0
   %PSTATE:35 AG:1 IE:0 PRIV:1 AM:0 PEF:1 RED:1 MM:0 TLE:0 CLE:0 MG:0 IG:0
   %ASI:15  %CCR:44  XCC:nZvc   ICC:nZvc