EBC Exercise 23 Configuring the Kernel

These instructions are for the 3.8 kernel. See EBC Exercise 23 Configuring the Kernel - bitbake for the 3.2 kernel.

In a previous exercises (EBC Exercise 08a Cross-Compiling and EBC Exercise 08 Installing Development Tools) you learned how to get and compile the kernel. Here we'll look at configuring it.

Finding the kernel sources
First set up the environment and go to the kernel directory

host$ source ~/crossCompileEnv.sh (set up in EBC Exercise 08a Cross-Compiling) host$ cd ~/BeagleBoard/linux-dev/KERNEL

Getting kernel make help
Once there try some of the make commands. Help is a good place to start.

host$ make help | less Cleaning targets: clean          - Remove most generated files but keep the config and enough build support to build external modules mrproper       - Remove all generated files + config + various backup files distclean      - mrproper + remove editor backup and patch files Configuration targets: config         - Update current config utilising a line-oriented program menuconfig     - Update current config utilising a menu based program xconfig        - Update current config utilising a QT based front-end gconfig        - Update current config utilising a GTK based front-end ... This produces a list of common make targets.

Finding and installing support software
There are several ways to configure the kernel. make config will prompt you line-by-line for each of the settings, very tedious, not recommended. Try

host$ make menuconfig *** Unable to find the ncurses libraries or the *** required header files. *** 'make menuconfig' requires the ncurses libraries. ***  *** Install ncurses (ncurses-devel) and try again. *** make[1]: *** [scripts/kconfig/dochecklxdialog] Error 1 make: *** [menuconfig] Error 2 If you get the error above, you need to install the ncurses library. Here are notes on how to discover what to install and installing it.

NOTE FOR UBUNTU USERS: 'sudo apt-get install libncurses5-dev' without quotes will install ncurses

Configuring the kernel
Try the various interfaces for configuring the kernel.

host$ make menuconfig host$ make xconfig host$ make gconfig

I had to run the following to get these to work. host$ sudo apt install libncurses5-dev host$ sudo apt install qt4-dev-tools host$ sudo apt install libglade2-dev

Recovering
If your Beagle fails to boot, follow the EBC_Exercise_22_Recovering instructions to recover.