openadk/docs/customize-kernel-config.txt

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[[kernel-custom]]
Customizing the Linux kernel configuration
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

The Linux kernel configuration can be customized using +make menuconfig+.
OpenADK uses a combination of Linux miniconfig feature and user defined
features to generate a valid Linux configuration for your target.
Some features and drivers are not selectable via +make menuconfig+, either
because your choosen target system does not have support for it or the
option is not implemented, yet. OpenADK uses some kind of abstraction
layer between the real full featured and complicated Linux kernel configuration
and you. It is not perfect and does include a lot of manual work in
+target/linux/config+, but it works in an acceptable way.

If you just want to view the Linux configuration, which is actually
used for your target, you can execute following command:

---------------
 $ make kernelconfig
---------------

Any changes here will get lost and will not be used to generate a kernel for
your target. If you want to change the existing kernel configuration you need
to follow these steps.

The basic kernel configuration used for your choosen target is concatenated from
following two files: 
+target/linux/kernel.config+ and +target/<arch>/kernel/<system>+.

So if you would like to change any basic stuff, just edit the files and recreate your
firmware via:

---------------
 $ make
---------------

OpenADK automatically recognizes any change and will rebuild the kernel.

The base kernel configuration for your target generated by OpenADK is normally just enough to
bootup the system with support for your board, serial console, network card and boot medium.
(like a hard disk, sd card or flash partition)

If you need to enable some new optional drivers or features, which are not available in
+make menuconfig+, you need to dig in +target/linux/config+. There is the abstraction layer
for the real kernel configuration.