If you get the following messages when upgrading your kernel or distro version:
W: Possible missing firmware /lib/firmware/tigon/tg3_tso5.bin for module tg3
W: Possible missing firmware /lib/firmware/tigon/tg3_tso.bin for module tg3
W: Possible missing firmware /lib/firmware/tigon/tg3.bin for module tg3
You can fix it by installing the package firmware-linux-nonfree
Make sure your /etc/apt/sources includes non-free sources such as:
deb http://ftp.uk.debian.org/debian/ squeeze main contrib non-free
deb-src http://ftp.uk.debian.org/debian/ squeeze main contrib non-free
Install using:
apt-get update
apt-get install firmware-linux-nonfree