[meta-fsl-ppc] How to change the kernel config?

[meta-fsl-ppc] How to change the kernel config?

[Joerg Albert]

Hi,

I'm quite a newbie to Yocto, sorry if this is a dumb question.

I want to tweak the kernel config for P2041RDB with Freescale SDK 1.6 using a separate custom layer containing
a recipe-kernel/linux/linux-qoriq-sdk_3.12.bbappend. The layer config seems to be fine,

bitbake-layers show-appends

recognizes it.

I've first tried to to use a configuration fragment (as described in the Yocto kernel documentation in chapter 2.2.3), but
this seems to fail as the base recipe does not inherit linux-yocto, but kernel.

Putting a files/defconfig there with a line like

SRC_URI += "files://defconfig"

didn't work either - I guess due to the special handling of .config via KERNEL_DEFCONFIG in linux-qoriq-sdk.inc in meta-fsl-ppc.

At last I tried

DELTA_KERNEL_DEFCONFIG += "${THISDIR}/files/my_incremental_config_change"

but this searches the files in meta-fsl-ppc/recipes-kernel/linux/files (or inside the source code tree of the kernel), while I'd
prefer to have it inside my custom layer.

What is the easiest way to have a kernel config change (incremental preferred) with all files inside a custom layer?

Cheers,
Joerg

Re: [meta-fsl-ppc] How to change the kernel config?

[zhenhua.luo]

Hi Joerg, 

> -----Original Message-----
> From: meta-freescale-bounces@yoctoproject.org [mailto:meta-freescale-
> bounces@yoctoproject.org] On Behalf Of Joerg Albert
> 
> I've first tried to to use a configuration fragment (as described in the
> Yocto kernel documentation in chapter 2.2.3), but this seems to fail as
> the base recipe does not inherit linux-yocto, but kernel.
[Luo Zhenhua-B19537] The feature fragment is not used by FSL QorIQ SDK currently.  

> Putting a files/defconfig there with a line like
> 
> SRC_URI += "files://defconfig"
[Luo Zhenhua-B19537] With this way, you need to change KERNEL_DEFCONFIG in meta-fsl-ppc/conf/machine/p2041rdb.conf to point to your kernel defconfig. 

> didn't work either - I guess due to the special handling of .config via
> KERNEL_DEFCONFIG in linux-qoriq-sdk.inc in meta-fsl-ppc.
> 
> At last I tried
> 
> DELTA_KERNEL_DEFCONFIG += "${THISDIR}/files/my_incremental_config_change"
> but this searches the files in meta-fsl-ppc/recipes-kernel/linux/files
> (or inside the source code tree of the kernel), while I'd prefer to have
> it inside my custom layer.
[Luo Zhenhua-B19537] Currently kernel recipe searches the delta defconfig in ${S} and ${S}/arch/powerpc/configs/${deltacfg}".
 
> What is the easiest way to have a kernel config change (incremental
> preferred) with all files inside a custom layer?
[Luo Zhenhua-B19537] Following is my suggestion. 
	1. copy defconfig in <custom_layer>/recipe-kernel/linux/files/
	2. ensure following content is in <custom_layer>/recipe-kernel/linux/linux-qoriq-sdk_3.12.bbappend
	FILESEXTRAPATHS_prepend := "${THISDIR}/files:"
	SRC_URI += "files://defconfig"
	3. redefine KERNEL_DEFCONFIG in conf files in the custom layer, e.g, conf/local.conf
	KERNEL_DEFCONFIG = "${WORKDIR}/defconfig"


Best Regards,

Zhenhua

Re: [meta-fsl-ppc] How to change the kernel config?

[Joerg Albert]

Hi,

zhenhua.luo@... <zhenhua.luo@...> writes:
> [Luo Zhenhua-B19537] Following is my suggestion. 
> 	1. copy defconfig in <custom_layer>/recipe-kernel/linux/files/
> 	2. ensure following content is in
<custom_layer>/recipe-kernel/linux/linux-qoriq-sdk_3.12.bbappend
> 	FILESEXTRAPATHS_prepend := "${THISDIR}/files:"
> 	SRC_URI += "files://defconfig"
> 	3. redefine KERNEL_DEFCONFIG in conf files in the custom layer, e.g,
conf/local.conf
> 	KERNEL_DEFCONFIG = "${WORKDIR}/defconfig"

sorry for the delay.
Unfortunately this doesn't work. I've got a copy of my defconfig in
${WORKDIR} but as kernel_do_configure in meta/classes/kernel.bbclass contains:

        if [ -f "${WORKDIR}/defconfig" ] && [ ! -f "${B}/.config" ]; then
                cp "${WORKDIR}/defconfig" "${B}/.config"

and meta-fsl-ppc/recipes-kernel/linux/linux-qoriq-sdk.inc runs:

  do_configure_prepend() {

        cp ${KERNEL_DEFCONFIG} ${B}/.config

before kernel_do_configure, my ${WORKDIR}/defconfig is not copied into
{B}/.config.

Cheers,
Joerg

Re: [meta-fsl-ppc] How to change the kernel config?

[Joerg Albert]

Hi,

just a followup - I gave up the idea to create a custom layer and modified files in meta-fsl-ppc instead. Not nice, as we have to port these changes to every new
SDK release.

Regards,
Joerg