[U-Boot] zImage on ARM

[Wolfgang Denk]

Dear =?iso-8859-1?Q?Lo=EFc?= Minier,

In message <20100903214753.GA8552 at bee.dooz.org> you wrote:
> On Fri, Sep 03, 2010, Wolfgang Denk wrote:
> > > I have a client that has asked me to look into loading zImage files
> > > instead of uImage for some ARM based boards.
> > >
> > Why?
>
>  It's the direct output of the kernel build process; typically,
>  distributions ship a /boot/zImage-foo which gets converted into an
>  uImage and flashed if the bootloader is u-boot.  If that step could be
>  skipped, it would make things easier!

zImage does not contain any visible information about what it is,
when it was build, etc. It is not checksum protected so you cannot
verify if the image you just downloaded is good enough to erase what
you have in flash, etc. etc.

> > Note that the mainline ARM kernel does not make use of this; instead,
> > it adds the preloader anyway.  I never understood why.
>
>  Seems zImage is quite widespread now; would it make sense to allow
>  builing u-boot without that code and rely on the kernel code to unpack?

Why duplicating the stuff again and again and again?

>  Or should u-boot just gain a new image type for zImage?

Why not use uImage like we do with other architectures? 

Why is it that ARM always has to try to reinvent the wheels?

Best regards,

Wolfgang Denk

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