You can now upgrade your BIOS relatively easily (without JTAG).
I suppose I don't need to say this, but I will anyhow: USE ENTIRELY
AT YOUR OWN RISK! This is a convenience utility for people who can't
be bothered to get their JTAG cable out the drawer to try out a new
version of Biffboot. Noobs, please get your friend to do it, and then
blame them when it goes wrong :).
1) Download the image 'upgrade-kernel-rootfs.img' from
2) flash it to your Bifferboard. It should work on 1, 4 or 8MB
3) Set kernel command-line to just 'console=uart,io,0x3f8'
4) Boot the image
5) At the console setup a an IP address for the board with e.g.
'ipconfig eth0 192.168.0.66'
6) Now you can ftp your new bootloader to the board (use username
'root', no password to login)
7) Check that you have a device /dev/biffupgrade. It should just
appear after boot.
8) Flash your new BIOS like this:
cat biffboot-000102030405-8M-v3_9rc4_community.bin > /dev/biffupgrade
There are some basic sanity checks on the image before writing it to
flash, in particular you will need to recompile the image if you want
to flash some alternative BIOS, this check looks for the Biffboot
signature. At least it should catch problems such as trying to write
a zipped BIOS image to the flash.
Some kernel messages will tell you how things are going. The flash
should complete in just seconds. If it takes more than about ten
you've probably got a brick. Sorry.
Here is what it just printed for me:
/ # cat biffboot-000102030405-v3_10_community.bin > /dev/biffupgrade
BIFFUPGRADE: Write buffer is full, writing to flash now
BIFFUPGRADE: Sanity check passed, erasing BIOS area
Sector erased in 214673 ticks
BIFFUPGRADE: Writing data, do not switch off until complete
BIFFUPGRADE: BIOS area written. Please reboot.
/ # reboot
/ # umount: can't remount rootfs read-only
The system is going down NOW!
Sent SIGTERM to all processes
Sent SIGKILL to all processes
Requesting system reboot
BIFFBOOT v3.10 000102030405 32-bit Loader by bifferos (c) 2012
Redistribution prohibited, all rights reserved.
'help' or '?' for a list of commands
000F0000 loaded from flash.
Booting Linux with: console=uart,io,0x3f8
Decompressing Linux... Parsing ELF... done.