Booting Linux Kernel without bootloader

Grant Likely grant.likely at
Wed Aug 2 14:17:41 EST 2006

On 7/25/06, Clint Thomas <cthomas at> wrote:
> Hey guys,
> I have gone through the Linuxppc embedded and dev lists for information
> related to what I am trying to do, but was unable to find exactly what i'm
> looking for.
> Basically, the system I want linux running on does not require the
> initialization of hardware that U-boot provides, or at least it does not
> need it to boot the linux kernel. I want to load an uncompressed linux
> kernel into memory and start the execution of the kernel, without using any
> kind of bootloader. Is this possible? Or does linux need some kind of
> firmware or other software to tell it to start executing? Thanks for any
> info you might have.

Loading a kernel into memory and starting execution *is* a boot loader.  :)

You could use the bootwrapper that is in the kernel source tree
(zImage).  If a zImage's entry point is at the execution entry point,
then it will start the Linux kernel correctly.  However, it is still a
compressed image.

If you *really* need an uncompressed image, I would start with the
bootwrapper and hack it to work with an non-gzipped kernel image.
However, why do you want to do it this way?  You probably won't gain
much in boot time and it will be more difficult to maintain.


Grant Likely, B.Sc. P.Eng.
Secret Lab Technologies Ltd.
grant.likely at
(403) 399-0195

More information about the Linuxppc-embedded mailing list