regarding modifying kernel in petalinux 2021.2 version

[neels]

Hi,

I am trying to modify the kernel to disable power management in linux.
I am using petalinux 2021.2 version.

I use petalinux-config -c kernel and make the necessary modification .  Then I save the changes. The menuconfig prompts to save it in a file, I give it a name and said it saved the file (say kchanges.config).
But when I search for the file (kchanges.config) in the build directory, I cannot find the .config file.

Moreover, when I do a petalinux-build after the above kernel changes. The above power management changes doesn't seems to have taken effect.

Can someone please explain how to correctly make kernel modification in petalinux 2021.2 version.

Thanks

[M Kirberg]

Hi,

you do not have to do anything. Petalinux (Yocto) creates a kernel-config fragment in the directory meta-user\recipes-kernel\linux\linux-xlnx for you.
This will be merged to reach a final .config.

However, in your case this does not seem to be the case.
Specifically what setting are you trying to achieve (CONFIG_XXX=n) ?

If you need more debugging possibilities you can use the underlying bitbake with tasks like:
https://docs.yoctoproject.org/singleindex.html#do-kernel-configcheck

see https://docs.xilinx.com/r/en-US/ug1144-petalinux-tools-reference-guide/Accessing-BitBake/Devtool-in-a-Project for how to fire up bitbake for your petalinux project.

Best,
Markus