FreeBSD on Broadcom Sentry5 devices

[Bruce M. Simpson]

Hi all,

I'd like to announce that a FreeBSD kernel is able to boot to mountroot 
on real MIPS32 hardware: a Netgear WGT634U.

The Linksys WRT54G uses the A0 rev of the BCM4710 which is notorious for 
containing some CPU bugs requiring gcc toolchain patches to workaround. 
The WGT634U uses a more recent Sentry5 spin which does not have these 
issues.

The Broadcom CFE firmware is able to load a FreeBSD ELF kernel via TFTP 
with some tweaks to the linker script. There is basic support code in 
NetBSD for CFE which may be worth looking at.

What needs to be done to support this hardware is to port Broadcom's 
Linux support package for the Sonics SiliconBackplane. The code looks 
like it was originally written for a BSD, so this shouldn't be too 
complex. This stuff is nowhere ready for prime time yet -- and I would 
like to iron a few things out before committing to p4.

Board level reset is very simple -- write to a register. Serial I/O uses 
uart(4); it is currently kludged to use the hard mapped physical 
addresses on this board just as the MALTA target does. Oh, and the clock 
needs to be calibrated properly; DELAY() is currently stubbed out, 
otherwise you get lots of divide-by-zero errors.

This is the output from a Netgear WGT634U access point:

CFE version 1.0.34 for BCM95365R (32bit,SP,LE)
Build Date: Tue Feb 24 03:21:41 CST 2004 (root at jackylinux)
Copyright (C) 2000,2001,2002 Broadcom Corporation.

Add MAC client version(DNI).
Initializing Arena.
Initializing Devices.
et0: Broadcom BCM47xx 10/100 Mbps Ethernet Controller
CPU type 0x29007: 200MHz
Total memory: 0x2000000 bytes (32MB)

Total memory used by CFE:  0x81BB1280 - 0x82000000 (4517248)
Initialized Data:          0x81BB1280 - 0x81BB3E90 (11280)
BSS Area:                  0x81BB3E90 - 0x81BB45D0 (1856)
Local Heap:                0x81BB45D0 - 0x81FB45D0 (4194304)
Stack Area:                0x81FB45D0 - 0x81FB65D0 (8192)
Text (code) segment:       0x81FB65E0 - 0x81FFFFB0 (301520)
Boot area (physical):      0x01B70000 - 0x01BB0000
Relocation Factor:         I:E23B65E0 - D:01BB0280

configure vlans
*****************************************************************
*********************** VLAN Driver initial  ********************
*****************************************************************
Process LAN port(2-5) vlan Architecture...
SUCCESS: trying to create VLAN 0 for switch
SUCCESS: trying to add LAN port

Process WAN port(2-5) vlan Architecture...
SUCCESS: trying to create VLAN 0 for switch
SUCCESS: trying to add WAN port
SUCCESS: enable ports  success
configure vlans...done
Device eth0:  hwaddr 00-0F-B5-3D-52-90, ipaddr 192.168.123.123, mask not set
        gateway not set, nameserver not set
CFE> boot -elf 192.168.123.16:/kernel
Loader:elf Filesys:tftp Dev:eth0 File:192.168.123.16:/kernel Options:(null)
***************************
****  MAC Client V1.0  ****
***************************
et0macaddr value :flag =0 value=00-0f-b5-3d-52-90
et1macaddr value :flag =0 value=00-0f-b5-3d-52-91
MAC exist at least one
system ethernet mac exist and not default....
Skip mac client process.....
Loading: 0x80001000/2014752 0x801eef00/107428 0x802092a4/96380 Entry at 
0x80001000
Closing network.
et0: link down
Starting program at 0x80001000
entry: mips_init()
  picache_stride    = 4096
  picache_loopcount = 2
  pdcache_stride    = 2048
  pdcache_loopcount = 2
mips_cache_ops.mco_pdcache_wbinv_all  == 0x8018a7d0
Exception vector at 80000000 almost out of space
Kernel page table maps 16384 4K pages and is 511K
KDB: debugger backends: ddb
KDB: current backend: ddb
MIPS32 clock: 10000000 Hz
Copyright (c) 1992-2007 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
        The Regents of the University of California. All rights reserved.
FreeBSD is a registered trademark of The FreeBSD Foundation.
FreeBSD 7.0-CURRENT #40: Wed May  2 14:11:58 BST 2007
    
bms at anglepoise.lon.incunabulum.net:/usr/obj/mips/usr/home/bms/p4/mips2/sys/SENTRY5
cpu0: Broadcom processor v7.144
  MMU: Standard TLB, 32 entries
  L1 i-cache: 2 ways of 256 sets, 16 bytes per line
  L1 d-cache: 2 ways of 256 sets, 16 bytes per line
clock0: <Generic MIPS32 ticker> on motherboard
clock0: [FILTER]
Timecounter "MIPS32" frequency 10000000 Hz quality 800
Timecounters tick every 10.000 msec

Manual root filesystem specification:
  <fstype>:<device>  Mount <device> using filesystem <fstype>
                       eg. ufs:/dev/da0a
  ?                  List valid disk boot devices
  <empty line>       Abort manual input

mountroot>
db> call cpu_reset
Resetting...