[Buildroot] Any way to override .config settings?

Hi buildrooters

I need to be able to build a system from an svn repository using a
bunch of different revisions for different elements. For example, I
might want to use the kernel at r 1234, u-boot at r 4567 and the
rootfs+apps at r 3344.

Now I could achieve this by going into the .config with menuconfig and
changing the config, but I would prefer to be able to have a file of
revisions to use and have buildroot pick up those revision symbols
instead.

I guess there are a few ways this could be handled:

1) Is there a built in mechanism in buildroot to include extra symbols
and override those in .config?

2) Run my own script that nobbles the .config using sed etc.

Is there something built in to buildroot that will do this?

Thanks

Charles

On 19/12/12 23:20, Charles Manning wrote:

I need to be able to build a system from an svn repository using a
bunch of different revisions for different elements. For example, I
might want to use the kernel at r 1234, u-boot at r 4567 and the
rootfs+apps at r 3344.

  Uh? Sounds like a horrible idea to me.

Now I could achieve this by going into the .config with menuconfig and
changing the config, but I would prefer to be able to have a file of
revisions to use and have buildroot pick up those revision symbols
instead.

  I don't see the relation between the .config and svn revisions.

I guess there are a few ways this could be handled:

1) Is there a built in mechanism in buildroot to include extra symbols
and override those in .config?

  Yes, the package override file: BR2_PACKAGE_OVERRIDE_FILE, defaults to 
$(TOPDIR)/local.mk. I use this to include a bunch of project-specific .mk 
files that add packages without requiring a Config.in.


  Regards,
  Arnout

2) Run my own script that nobbles the .config using sed etc.

Is there something built in to buildroot that will do this?

Thanks

Charles

-- 
Arnout Vandecappelle                               arnout at mind be
Senior Embedded Software Architect                 +32-16-286540
Essensium/Mind                                     http://www.mind.be
G.Geenslaan 9, 3001 Leuven, Belgium                BE 872 984 063 RPR Leuven
LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle
GPG fingerprint:  7CB5 E4CC 6C2E EFD4 6E3D A754 F963 ECAB 2450 2F1F

On Thu, Dec 20, 2012 at 1:04 PM, Arnout Vandecappelle [off-list ref] wrote:

On 19/12/12 23:20, Charles Manning wrote:

quoted

I need to be able to build a system from an svn repository using a
bunch of different revisions for different elements. For example, I
might want to use the kernel at r 1234, u-boot at r 4567 and the
rootfs+apps at r 3344.

 Uh? Sounds like a horrible idea to me.

Why does it sound like a terrible idea?

quoted

Now I could achieve this by going into the .config with menuconfig and
changing the config, but I would prefer to be able to have a file of
revisions to use and have buildroot pick up those revision symbols
instead.

 I don't see the relation between the .config and svn revisions.

Well svn revisions are useful to me with the changes I have made to
fetch linux from a custom location. I have not submitted that patch
yet. The same would apply for a git revison.

We want to lock the versions we build into releases or use a different
release for experimental reasons.  Overriding is sometimes less
intrusive than changing the .config.

quoted

I guess there are a few ways this could be handled:

1) Is there a built in mechanism in buildroot to include extra symbols
and override those in .config?

 Yes, the package override file: BR2_PACKAGE_OVERRIDE_FILE, defaults to
$(TOPDIR)/local.mk. I use this to include a bunch of project-specific .mk
files that add packages without requiring a Config.in.

In a separate thread to this, I submitted a patch that follows the
package overriding idea to override the config

 Regards,
 Arnout

quoted

2) Run my own script that nobbles the .config using sed etc.

Is there something built in to buildroot that will do this?

Thanks

Charles

--
Arnout Vandecappelle                               arnout at mind be
Senior Embedded Software Architect                 +32-16-286540
Essensium/Mind                                     http://www.mind.be
G.Geenslaan 9, 3001 Leuven, Belgium                BE 872 984 063 RPR Leuven
LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle
GPG fingerprint:  7CB5 E4CC 6C2E EFD4 6E3D A754 F963 ECAB 2450 2F1F

On 20/12/12 01:13, Charles Manning wrote:

On Thu, Dec 20, 2012 at 1:04 PM, Arnout Vandecappelle[off-list ref]  wrote:

quoted

On 19/12/12 23:20, Charles Manning wrote:

quoted

I need to be able to build a system from an svn repository using a
bunch of different revisions for different elements. For example, I
might want to use the kernel at r 1234, u-boot at r 4567 and the
rootfs+apps at r 3344.

  Uh? Sounds like a horrible idea to me.

Why does it sound like a terrible idea?

  I thought you meant the buildroot directories would be at different 
versions. But you just want to override the 
BR2_LINUX_KERNEL_CUSTOM_GIT_VERSION, that's OK of course.

[snip]

quoted

quoted

1) Is there a built in mechanism in buildroot to include extra symbols
and override those in .config?

  Yes, the package override file: BR2_PACKAGE_OVERRIDE_FILE, defaults to
$(TOPDIR)/local.mk. I use this to include a bunch of project-specific .mk
files that add packages without requiring a Config.in.

In a separate thread to this, I submitted a patch that follows the
package overriding idea to override the config

  Since it does exactly the same as BR2_PACKAGE_OVERRIDE_FILE, I don't 
see the point... Unless you want to start overriding toolchain configs.

  Actually, I don't see much point to override the .config - why not just 
save a different .config?


  Regards,
  Arnout


-- 
Arnout Vandecappelle                               arnout at mind be
Senior Embedded Software Architect                 +32-16-286540
Essensium/Mind                                     http://www.mind.be
G.Geenslaan 9, 3001 Leuven, Belgium                BE 872 984 063 RPR Leuven
LinkedIn profile: http://www.linkedin.com/in/arnoutvandecappelle
GPG fingerprint:  7CB5 E4CC 6C2E EFD4 6E3D A754 F963 ECAB 2450 2F1F

On Wed, Dec 19, 2012 at 4:20 PM, Arnout Vandecappelle [off-list ref] wrote:

On 20/12/12 01:13, Charles Manning wrote:

quoted

quoted

quoted

1) Is there a built in mechanism in buildroot to include extra symbols
and override those in .config?

  Yes, the package override file: BR2_PACKAGE_OVERRIDE_FILE, defaults to
$(TOPDIR)/local.mk. I use this to include a bunch of project-specific .mk
files that add packages without requiring a Config.in.

In a separate thread to this, I submitted a patch that follows the
package overriding idea to override the config

 Since it does exactly the same as BR2_PACKAGE_OVERRIDE_FILE, I don't see
the point... Unless you want to start overriding toolchain configs.

 Actually, I don't see much point to override the .config - why not just
save a different .config?

I agree. From a maintenance point of view, having one file (.config or
defconfig) that describes how something is built is much nicer than
having a .config and various makefiles that hack at it.

Also, the buildroot make system is a mechanism that can easily be
extended by an external script or makefile. We should resist the
temptation to complicate the buildroot system just to fit a subset of
people's strange build desires. Keeping it simple and clean and
limiting the number of targets is good.

Regards, Steve