Although there is a Bifferboard profile in OpenWrt I was never able to get it to work properly with the 2.6.30 kernel. I had better luck last night making a couple of tweaks to the Sitecom profile and switching to 2.6.32.9 kernel:
1) Download the script in the 'code' section below.
2) Obtain OpenWrt Backfire sources:
$> svn co svn://svn.openwrt.org/openwrt/branches/backfire
First you have to edit files in backfire/target/linux/rdc/
4) Open the Makefile and change
LINUX_VERSION:=2.6.30.10
to
LINUX_VERSION:=2.6.32.9
5) Open config-2.6.32 and change the line CONFIG_CMDLINE from:
CONFIG_CMDLINE="console=ttyS0,38400 rootfstype=squashfs,jffs2"
to
CONFIG_CMDLINE="rootfstype=squashfs,jffs2"
In other words remove the bit about setting the console=tty0,38400. This will fall back to use the settings from the bootloader.
6) Run 'make menuconfig', select the RDC321x target system.
7) Select target profile, "Devices from Sitecom (WL-153, DC-230)"
8) Run 'make' and wait a while.
9) Run the script below to combine the built kernel and JFFS images.
This should create 'biff-firmware.img'
Don't flash it to the board yet! First you have to change Biffboot config.
10) At the Biffboot prompt, lower the kernel_max value to 0x0010, instead of the default 0x0020. It *may* work without this change, but this will result in slightly faster kernel boot.
11) Also at the Biffboot prompt, change the kernel command-line to remove the root=/dev/sda1 and rootwait parts. This is needed so the JFFS image will boot correctly.
12) Flash the file to the Bifferboard as you would a normal kernel, either with the serial cable or via Ethernet. You may have to wait some time for the first boot, due to JFFS erasing trailing blocks.
#!/usr/bin/env python
"""
Create Bifferboard firmware based on Sitecom image build
"""
import sys, os
root = "backfire/build_dir/linux-rdc"
kernel = os.path.join(root, "bzImage")
jffs = os.path.join(root, "root.jffs2-64k")
kernel_extent = 0x100000
config = 0x6000
if __name__ == "__main__":
k = file(kernel, "rb").read()
j = file(jffs,"rb").read()
if len(k) > (kernel_extent - config):
raise IOError("Kernel too large")
fw = k
# Pad up
while len(fw) < (kernel_extent - config):
fw += "\xff"
fw += j
# Check length of total
if len(fw) > (0x800000 - 0x10000 - 0x6000):
raise IOError("Rootfs too large")
target = "biff-firmware.img"
file(target,"wb").write(fw)
print "Firmware written to '%s'" % target(Last edited by bifferos on 15 Jul 2010, 10:25)