[Buildroot] BSP patch

[Ulf Samuelsson <ulf@atmel.com>]

> On Wed, Mar 21, 2007 at 11:24:32PM +0100, Ulf Samuelsson wrote:
>>Any chance of having this reviewed soon?
>>I am kinda stuck on AVR32 before that is applied.
>
> There was someone on irc that had an alternative approach. He said that
> he'd be in contact with you to discuss both approaches. Unfortunately
> this discussion didn't end up on the list.. What was the outcome of that
> discussion?
>

I think you refer to the discussions I had with S?ren Straarup
It is actually not two approaches.

He wants an easy way to configure buildroot by having a set
of ".config" files and a way to select  *which* config file
by doing

$ make <board>-defconfig

where the defconfig files are stored in the "configs" directory.

I actually have a "configs" directory as well in my private buildroot
but I copy stuff manually to the top level.
I think that S?ren's patch is orthogonal to my work.


The BSP patch is really there to allow two different configurations
to be built within the same buildroot directory so they can share:

* toolchain
* root file system build directory.
but have different configurations for linux kernel and busybox
and eventually you may want to have different content of the root file
system.

The solution is to create a new directory structure
target_build_<arch>/<board> where everything is built.
The patch allows pre/postfixes to this directory name.

When I have time, I would like to be able to download kernel patches
to this directory instead of storing the patch in the target directory.

The current linux.mk is very limited in functionality and forces
duplication of the linux patch for each board.
I do not see why the same patch (size > 1 MB) should be stored 10 times
just because I have 10 boards.

The BSP patch also put some structure on where the result ends up.
Today everything is stored in the top directory, but if you
want to build multiple boards, then you are going to get a lot of clutter.

The BSP patch will put bootloaders, kernel and root file systems in
binaries/<board>

S?ren also would like to separate the target build from the build
of the root file system, so I think he supports this patch.



So in short, I think there is really no reason to delay either of the
patches.



Best Regards
Ulf Samuelsson