Early serial console slowness and reboot

[Andrew Randrianasulu <randrik_a%yahoo.com@localhost>]

On O2 system i have  kernel compiled form sources dated around 20 feb 2009. It 
behaves normally when started in local mode (when i have keyb, mouse and 
monitor plugged in), but when i have only serial console attached, kernel just 
print this text very slowly:

----------


> bootp():/netbsd-5.99.7                            
Setting $netaddr to 192.168.1.3 (from server )
Obtaining /netbsd-5.99.7 from server          
5098080+260344 entry: 0x80069000     
ÂÂ                              
  Copyright (c) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005,
    2006, 2007, 2008, 2009                                                 
    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 5.99.7 (GENERIC32_IP3x) #0: Sat Feb 21 00:59:43 GMT 2009
        guest@slax:/mnt/hdb2/obj/sys/arch/sgimips/compile/GENERIC32_IP3x
total memory = 256 MB                                                   
(6848 KB reserved for ARCS)
avail memory = 238 MB      
mainbus0 (root): SGI-IP32 [SGI, b], 1 processor
cpu0 at mainbus0: MIPS R5000 CPU (0x2321) Rev. 2.1 with built-in FPU Rev. 1..0
cpu0: 32KB/32B 2-way set-associative L1 Instruction cache, 48 TLB entries    
cpu0: 32KB/32B 2-way set-associative write-back L1 Data cache            
cpu0: 512KB/32B direct-mapped write-through L2 Unified cache 
crime0 at mainbus0 addr 0x14000000: rev 1.1 (CRIME_ID: 161) 
crmfb0 at mainbus0 addr 0x16000000: SGI CRIME Graphics Display Engine
crmfb0: initial resolution 1280x1024                                 
crmfb0: allocated 5242880 byte fb @ 0x80050000 (0xa1400000)
wsdisplay0 at crmfb0 kbdmux 1                              
mace0 at mainbus0 addr 0x1f000000
lpt0 at mace0 offset 0x380000 intr 4 intrmask 0xf0000
com0 at mace0 offset 0x390000 intr 4 intrmask 
0x3f00000:ocx:mem0:tn:nbmx:amep0araBaa,seWos<s sfc4c-btn1rscu: Got hangup signal

------

and machine reboot itself. Adding "-d" flag produce this:


-------
> bootp():/netbsd-5.99.7 "-d"                       
Setting $netaddr to 192.168.1.3 (from server )
Obtaining /netbsd-5.99.7 from server          
5098080+260344 entry: 0x80069000     
                                
Exception: <vector=Normal>
Status register: 0x20000002<CU1,IPL=8,MODE=KERNEL>
Cause register: 0x8024<CE=0,IP8,EXC=BREAK>        
Exception PC: 0x800dbca0, Exception RA: 0x8028bf0c
Breakpoint exception at address 0xffedffff        
  Saved user regs in hex (&gpda 0x81060aa8, &_regs 0x81060ca8):
  arg: 81070000 46 4f a                                        
  tmp: 81070000 8 a13fb048 80510000 fffffffd 8 80570000 80530000
  sve: 81070000 3fd5bbb2 0 46117f1f 0 3fbfa1c5 0 3e0b9933       
  t8 81070000 t9 0 at 0 v0 3fc60c9b v1 0 k1 40           
  gp 81070000 fp 0 sp 64823807 ra 0           
                                   
PANIC: Unexpected exception

[Press reset or ENTER to restart.]cu: Got hangup signal

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Anyone have some hints when this started? Netbsd-5 kernel boots ok with only 
serial console, but newest Xorg binaries were incompatible with 5.0-rc2 system, 
so i was forced to upgrade full userland, old netbsd-5 kernel no longer boot, i 
have working (sort of) X, but broken serial :)

PS: my router really weird device - now i can't ping it even from my x86 box. 
But Internet and netbooting still works ....