GNet Solutions » Hardware Hacking » Raspberry Pi

This is a guide on how I compile a kernel module for Raspbian on a Raspberry Pi 2.

Prepare the Environment¶

• Make sure the system is up to date:
  

  apt-get update && apt-get upgrade
  

• Install a few dependencies:
  

  apt-get install build-essential bc automake autoconf libtool gawk alien fakeroot zlib1g-dev uuid-dev libblkid-dev libselinux-dev parted lsscsi wget ncurses-dev
  

Download the Kernel¶

• Clone the latest raspberry pi toolchain:
  

  cd /usr/src
  git clone https://github.com/raspberrypi/tools
  

• Export the toolchain path:
  

  export CCPREFIX=/usr/src/tools/arm-bcm2708/arm-bcm2708-linux-gnueabi/bin/arm-bcm2708-linux-gnueabi-
  

• Download the latest linux kernel for the raspberry pi:
  

  cd /usr/src
  git clone https://github.com/raspberrypi/linux
  

• Then checkout the current kernel version:
  

  cd /usr/src/linux
  zgrep "* firmware as of" /usr/share/doc/raspberrypi-bootloader/changelog.Debian.gz | head -1 | awk '{ print $5 }' | git checkout -
  

• Then export the kernel source path:
  

  export KERNEL_SRC=/usr/src/linux
  

Compile the Kernel Modules¶

• Load the configs kernel module:
  

  modprobe configs
  

• Load the current config into the kernel source directory:
  

  zcat /proc/config.gz > /usr/src/linux/.config
  

• Prepare the kernel build environment:
  

  cd /usr/src/linux
  make mrproper
  

• Use the previous kernel config with the new kernel build environment:
  

  make oldconfig
  

• Build the kernel:
  

  make -j4
  

• Now use a make file that references the kernel source directory to built the kernel module only, use a line like:
  

  PREFIX = /usr/src/tools/arm-bcm2708/arm-bcm2708-linux-gnueabi/bin/arm-bcm2708-linux-gnueabi-
  make -C /usr/src/linux M=$(SRC) modules
  

Resources¶

• http://lostindetails.com/blog/post/Compiling-a-kernel-module-for-the-raspberry-pi-2
• http://openstack.prov12n.com/openstack-on-raspberry-pi-part-2-getting-started/
• https://raspberrypicloud.wordpress.com/2013/03/12/building-an-lxc-friendly-kernel-for-the-raspberry-pi/
• http://elinux.org/Raspberry_Pi_Kernel_Compilation