I got my ThinkPad 820 to boot (from floppy) using a serial console.

The good news is that the onboard siop is working.  But there's bad
news too.  After a bit of time, the system stops responding to
(some) interrupts and everything other the console stops responding
and gets device timeouts.

[ using 205188 bytes of netbsd ELF symbol table ]
Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003
     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 1.6L (TP820) #0: Wed Jan 15 01:03:19 PST 2003
     matt@tbird.local:/u1/prep/kobj/TP820
Model: IBM PPS Model 6040 (E)
total memory = 49152 KB
avail memory = 40328 KB
using 640 buffers containing 2560 KB of memory
mainbus0 (root)
cpu0 at mainbus0: 603e (Revision 1.4), ID 0 (primary)
cpu0: HID0 90c000<DOZE,DPM,ICE,DCE>
extent_alloc(0xd0016fe0, 65536, 4) returned 35
extent `pciio' (0x8000 - 0xffff), flags = 0x0
pci0 at mainbus0 bus 0: indirect configuration space access
pci0: i/o space, memory space enabled
pchb0 at pci0 dev 0 function 0
pchb0: IBM product 0x0015 (rev. 0x04)
pcib0 at pci0 dev 11 function 0
pcib0: PIRQ[0]=15 PIRQ[1]=15
pcib0: Intel 82378ZB System I/O (SIO) (rev. 0x03)
siop0 at pci0 dev 12 function 0: Symbios Logic 53c810 (fast scsi)
siop0: interrupting at irq 13
scsibus0 at siop0: 8 targets, 8 luns per target
Western Digital 90C (VGA display, revision 0x03) at pci0 dev 14 function 0 
not configured
IBM product 0x001c (undefined subclass 0x80, revision 0x02) at pci0 dev 15 
function 0 not configured
ASCII Corporation product 0x7310 (video multimedia, revision 0x01) at pci0 
dev 16 function 0 not configured
isa0 at pcib0
com0 at isa0 port 0x3f8-0x3ff irq 4: ns16550a, working fifo
com0: console
pckbc0 at isa0 port 0x60-0x64
pckbd0 at pckbc0 (kbd slot)
pckbc0: using irq 1 for kbd slot
wskbd0 at pckbd0 mux 1
pms0 at pckbc0 (aux slot)
pckbc0: using irq 12 for aux slot
wsmouse0 at pms0 mux 0
lpt0 at isa0 port 0x3bc-0x3bf irq 7
pcppi0 at isa0 port 0x61
midi0 at pcppi0: PC speaker
spkr0 at pcppi0
isabeep0 at pcppi0
isapnp0 at isa0 port 0x279: ISA Plug 'n Play device support
mcclock0 at isa0 port 0x70-0x71: mc146818 or compatible
fdc0 at isa0 port 0x3f0-0x3f7 irq 6 drq 2
fd0 at fdc0 drive 0: 1.44MB, 80 cyl, 2 head, 18 sec
pcic0 at isa0 port 0x3e0-0x3e1 iomem 0xd0000-0xdffff irq
pcic0: controller 0 (Intel 82365SL Revision 1) has sockets A and B
pcic0: controller 1 (Unknown controller) has no sockets
pcmcia0 at pcic0 controller 0 socket 0
pcmcia1 at pcic0 controller 0 socket 1
isapnp0: no ISA Plug 'n Play devices found
biomask 2040 netmask 2040 ttymask 30c2
pcic0: controller 0 detecting irqs with mask 0x4a00:..9..11
pcic0: using irq 9 for socket events
scsibus0: waiting 2 seconds for devices to settle...
pcmcia0: CIS checksum failed
pcmcia0: CIS version PCMCIA 2.0 or 2.1
pcmcia0: CIS info: IBM Corp., Ethernet, 0934214, PC-NIC ENCC 990010759-001A
pcmcia0: Manufacturer code 0xa4, product 0x2
pcmcia0: function 0: network adapter, ccr addr 20000 mask b
pcmcia0: function 0, config table entry 1: I/O card; irq mask ffff; iomask 
5, iospace 0-1f; memspace 11000-14fff; mwait_required io16 irqpulse irqlevel
ne0 at pcmcia0 function 0 port 0x300-0x30f port 0x310-0x31f
ne0: IBM InfoMover Ethernet
ne0: Ethernet address 00:04:ac:d5:33:15
cd0 at scsibus0 target 3 lun 0: <IBM, CDRM00204     !G, 1.0F> cdrom removable
cd0: async, 8-bit transfers
sd0 at scsibus0 target 6 lun 0: <IBM, DVAS-2810, S1C0> disk fixed
sd0: 773 MB, 2770 cyl, 6 head, 95 sec, 512 bytes/sect x 1583568 sectors
sd0: sync (100.0ns offset 8), 8-bit (10.000MB/s) transfers
boot device: <unknown>
root device: ne0
dump device:
file system (default generic):
root on ne0
nfs_boot: trying DHCP/BOOTP
pcmcia0: card irq 11
nfs_boot: DHCP next-server: 192.168.7.52
nfs_boot: my_domain=local
nfs_boot: my_addr=192.168.7.22
nfs_boot: my_mask=255.255.255.0
nfs_boot: gateway=192.168.7.52
root on netra2:/clients/preppy/root

-- 
Matt Thomas               Internet:   matt@3am-software.com
3am Software Foundry      WWW URL:    http://www.3am-software.com/bio/matt/
Cupertino, CA             Disclaimer: I avow all knowledge of this message