Building Linux Kernel Building Linux Kernel Building Using LTIB Building Outside LTIB Downloading and installing GNU Toolchain and git Building Kernel from Freescale git repository Building Kernel Mainline About Linux Building Using LTIB Linux kernel can be easily built using Ltib. On Ltib menu, just select: [*] Configure the Kernel When you exit this menu, Ltib will show the Kernel Menuconfig as below: This is the Kernel Menuconfig, where it's possible to configure kernel options and drivers. After exit this menu, kernel will be built and stored at: <Ltib directory>/rootfs/boot Building Outside LTIB Downloading and installing GNU Toolchain and git When you install LTIB, a GNU toolchain is automatically installed on /opt/freescale/usr/local/ Kernel releases newer than 2.6.34 doesn't build on Toolchain 4.1.2, only on 4.4.1 or later Check on your host at /opt/freescale/usr/local/ the current installed Toolchain. Next step is to install GIT on host. For Ubuntu machines, use: sudo apt-get install git-core Building Kernel from Freescale git repository Freescale provides access to their own git kernel repository and can be viewed at: Freescale Public GIT To download the kernel source code, create a new folder and use the command:
git clone git://git.freescale.com/imx/linux-2.6-imx.git
OR
git clone http://git.freescale.com/git/cgit.cgi/imx/linux-2.6-imx.git
After some minutes, a folder called linux-2.6-imx will be created containing the Linux kernel Create a local git branch from a remote branch you want to use. Let's use branch origin/imx_3.0.15 as example: cd linux-2.6-imx
git checkout -b localbranch origin/imx_3.0.15
To check all available remote branches, use: git branch -r Export the cross compiler, architecture and the toolchain path: export ARCH=arm
export CROSS_COMPILE=arm-none-linux-gnueabi-
If using Toolchain 4.1.2: export PATH="$PATH:/opt/freescale/usr/local/gcc-4.1.2-glibc-2.5-nptl-3/arm-none-linux-gnueabi/bin/" OR If using Toolchain 4.4.4: export PATH="$PATH:/opt/freescale/usr/local/gcc-4.4.4-glibc-2.11.1-multilib-1.0/arm-fsl-linux-gnueabi/bin/" Copy the config file for the wanted platform on linux folder as example: cp arch/arm/configs/imx6_defconfig .config All platform config files are located at <linux directory>/arch/arm/configs/ Call menuconfig and change configuration (if needed) make menuconfig Now it's ready to be built: make uImage The zImage and uImage will be located at /arch/arm/boot/ folder. Building Kernel Mainline Mainline Kernel can be viewed on this link: https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git To download the kernel source code, create a new folder and use the command:
git clone git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
OR
git clone http://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
OR
git clone https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git
After some minutes, a folder called linux will be created containing the Linux kernel Create a local git branch from a remote branch you want to use. Let's use branch origin/linux-3.8.y as example: cd linux
git checkout -b localbranch origin/linux-3.8.y
To check all available remote branches, use: git branch -r Export the cross compiler, architecture and the toolchain path: export ARCH=arm export CROSS_COMPILE=arm-none-linux-gnueabi- If using Toolchain 4.4.4: export PATH="$PATH:/opt/freescale/usr/local/gcc-4.4.4-glibc-2.11.1-multilib-1.0/arm-fsl-linux-gnueabi/bin/" Configure to the platform you want to build kernel. For i.MX family, use imx_v6_v7_defconfig: make imx_v6_v7_defconfig All platform config files are located at <linux directory>/arch/arm/configs/ Call menuconfig and change configuration (only if needed, this is an optional step!) make menuconfig Now it's ready to be built: make -j4 uImage LOADADDR=0x70008000 - Use -j4 option to speed up your build in case or PC has 4 cores. It's optional. - IMPORTANT: Use the correct address for each processor. You can check the correct address value at linux/arch/arm/mach-imx/Makefile.boot. After build the uImage, build the dtb file (device tree binary). For i.MX53 QSB use: make imx53-qsb.dtb The uImage will be located at: linux/arch/arm/boot/ folder and dtb binary will be located at: linux/arch/arm/boot/dts About Linux For general Linux information, see About Linux
View full article