[Buildroot] BR 2012.rc1 :: wrong bootfiles?!

[Buildroot] BR 2012.rc1 :: wrong bootfiles?!

[MERCADIER Johann]

Hi all,
   I would like to mention a recurrent problem I have and which is the same
since the 2011.11 version of BR.
   When I successfully built a project I got uImage, MLO and u-boot.bin as
part of the boot process. Any of these files make me able to boot the card.
   At the moment I use MLO and u-boot.bin couple from an ubuntu distro and
I manually compile my own kernel image. In this way that's work.
   I've already try to use the uImage generated by BR with loader from the
ubuntu distro and the card didn't start at all.
   What then could be so different? Does someone else has to face the same
issue?

regards.

-- 
Cordialement.

___Johann MERCADIER___

:(){ :|:& };:
"I am the Unknown lead by the Unknowing.
I have done so much with so little for so long
that I am now qualified to do anything with nothing."
HOOSEEK (http://www.hooseek.com/) 1?moteur de recherche solidaire!
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[Buildroot] BR 2012.rc1 :: wrong bootfiles?!

[Thomas Petazzoni]

Le Fri, 9 Mar 2012 14:21:09 +0000,
MERCADIER Johann <johann.mercadier@imerir.com> a ?crit :

>    I would like to mention a recurrent problem I have and which is
> the same since the 2011.11 version of BR.
>    When I successfully built a project I got uImage, MLO and
> u-boot.bin as part of the boot process. Any of these files make me
> able to boot the card. At the moment I use MLO and u-boot.bin couple
> from an ubuntu distro and I manually compile my own kernel image. In
> this way that's work. I've already try to use the uImage generated by
> BR with loader from the ubuntu distro and the card didn't start at
> all. What then could be so different? Does someone else has to face
> the same issue?

Hum. I am not sure you realize that uImage is the kernel image, and
this image highly depends on 1/ the kernel version and 2/ the kernel
configuration.

So yes, if you give a completely wrong kernel configuration to
Buildroot, or tell Buildroot to build a kernel version that does not
work on your hardware, then the kernel image generated by Buildroot
will not work.

You seem to think that Buildroot does a lot of black magic behind the
back. Basically, what Buildroot does with your kernel is:

 1/ Download the kernel sources tarball according to the version you
 have specified

 2/ Extract this tarball

 3/ Apply the kernel configuration you have provided

 4/ Build the kernel by running 'make' (i.e, the normal build process
 of the Linux kernel)

 5/ Copy the uImage to output/images/

That's it. So if the kernel generated by Buildroot does not work for
you, there is 99.9999999% chances that your kernel version and/or
configuration is wrong, and only 0.00000001% chances that Buildroot is
at fault.

Best regards,

Thomas
-- 
Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com