Compile a uBoot Kernel
This is a tutorial of how to compile a uBoot kernel from vanilla gentoo-sources.
Contents
Get the sources
Right now (24 Nov 2008) the latest stable version is gentoo-sources-2.6.26-r2. If you want a newer kernel, simply edit /etc/portage/package.keywords and add this line: sys-kernel/gentoo-sources ~ppc
then download the kernel sources
# emerge -ua gentoo-sources
make a link to the kernel sources
# cd /usr/src # ln -sfn linux-2.6.26-gentoo-r2 linux
Edit your kernel config
Clean up before you begin:
# cd /usr/src/linux # make mrproper
Use the default KuroBox config:
# cp arch/powerpc/configs/linkstation_defconfig .config
Make sure the config is sane:
# make menuconfig
The default config is minimal. You'll have to enable support for any non-standard things you may be using. I use reiserfs and netatalk, so I enabled support for that filesystem and also for appletalk.
Compile your kernel
# make uImage && make modules && make modules_install
Sit back and listen to music. Go to the store. Wash the dog.
Backup your old kernel and dtb file
# cp /boot/uImage /boot/uImage.bak # cp /boot/kuroboxHG.dtb /boot/kuroboxHG.dtb.bak
Compile the dtb file
# cd /usr/src/linux/arch/powerpc/boot/dts # ../dtc -I dts -O dtb -V 16 -o /tmp/kuroboxHG.dtb kuroboxHG.dts # cp /tmp/kuroboxHG.dtb /boot/kuroboxHG.dtb
Install the kernel
# cp /usr/src/linux/arch/powerpc/boot/uImage /boot/uImage
Reboot
# reboot
With any luck, you'll be booting your new kernel.
Troubleshooting
If something goes wrong, simply boot in EM mode and copy your old kernel back.
# cp /boot/uImage.bak /boot/uImage # cp /boot/kuroboxHG.dtb.bak /boot/kuroboxHG.dtb # echo -n "OKOK" > /dev/fl3