1. Setup of the toolchain
You should make sure you have the tools for building the Linux Kernel and install them if you don’t have them. To install new software you should be with super user rights on your Linux machine, so do this type in a terminal.
$ sudo su
you will be asked for your password and then your prompt will change to # which means you are now the super user, all future commands should be run in this mode.
First update apt-get links by typing:
# apt-get update
Install the toolchain by typing the following.
# apt-get install gcc-4.7-arm-linux-gnueabihf ncurses-dev uboot-mkimage build-essential git
This will install: GCC compiler used to compile the kernal, the kernel config menu
uboot make image which is required to allow the SD card to book into the linux image, Git which allows you to download from the github which holds source code for some of the system, some other tools for building the kernel.
Note that if you use debian may be you will need to add:
deb http://www.emdebian.org/debian squeeze main
in the file below:
after the installation you now have all tools to make your very own A13 kernel image!
2. Building Uboot
For problems around u-boot use Linux-Sunxi mailing list at Google Groups: https://groups.google.com/forum/#!forum/linux-sunxi
First let’s make the directory where we will build the A13-OLinuXino linux:
# mkdir A13-OLinuXino_kernel_34/ # cd A13-OLinuXino_kernel_34/
Then let’s download the uboot sources from GitHub repository, note there are lot of branches but you have to use sunxi branch.
Note that the A13-OLinuXino board u-boot is tested with the next branch:
# git rev-parse --verify HEAD a5f58fbcf743fd5d239a69dae5049cdb169ef2b0
Download u-boot sourses:
# git clone -b sunxi https://github.com/linux-sunxi/u-boot-sunxi.git
After the download you should have a new directory
# cd u-boot-sunxi/
With the following command you can start the uboot build:
# make A13-OLinuXino CROSS_COMPILE=arm-linux-gnueabihf-
At the end of the process you can check if everything is OK by
# ls u-boot.bin u-boot-sunxi-with-spl.bin spl/sunxi-spl.bin spl/sunxi-spl.bin u-boot.bin u-boot-sunxi-with-spl.bin
If you got these files everything is complete, well done so far
# cd ..
You should be in the following directory
3. Building kernel sources for A13-OLinuXino
For problems around kernel use Linux-Sunxi mailing list at Google Groups: https://groups.google.com/forum/#!forum/linux-sunxi
Kernel sources for A13 are available on GitHub. Note that the following building is made with the revision below:
# git rev-parse --verify HEAD 77a43694fca9db61560b546ca94809535d37de0f
You can download the kernel sources using the following command:
# git clone https://github.com/linux-sunxi/linux-sunxi
After the download go to the kernel directory
# cd linux-sunxi/
Here you need from A13 configuration file a13_linux_defconfig. The file contains all kernel module settings.
then copy a13_linux_defconfig file to configs directory:
# cp a13_linux_defconfig linux-sunxi/arch/arm/configs/.
# make ARCH=arm a13_linux_defconfig
The result should be:
configuration written to .config
If you wish to make your changes in the kernel configuration do:
# make ARCH=arm menuconfig
The menuconfig changes a .config text file, which you can view/edit even with a text editor like vi,nano.
With this command you can add or remove different modules for the different peripherals in the kernel. Be careful when use this as this may cause the kernel to not work properly.
Note that before compiling kernel you have to do a patch related with I2C speed. The patch changes i2c speed from 200kHz to 100kHz.
If you want to use some of olimex’s i2c modules on UEXT then you need from this patch.
download the patch sunxi-i2c.patch
and apply the patch:
# patch -p0 < sunxi-i2c.patch
Now you can continue with kernel image compiling
# make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j4 uImage
when this finishs you will have uImage ready and the result should be:
Image Name: Linux-3.4.75+ Created: Mon Sep 16 13:39:04 2013 Image Type: ARM Linux Kernel Image (uncompressed) Data Size: 5450904 Bytes = 5323.15 kB = 5.20 MB Load Address: 40008000 Entry Point: 40008000 Image arch/arm/boot/uImage is ready
Now you can build the kernel modules:
# make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j4 INSTALL_MOD_PATH=out modules # make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j4 INSTALL_MOD_PATH=out modules_install
DONE! At this point you have uboot and kernel modules.
The uImage file is located in linux-sunxi/arch/arm/boot/
The kernel modules are located in
where 3.x.xx is kernel version
in our case the directory with modules is:
4. Format and setup the SD-card
We suggest 4GB class 10 micro sd-card but you can use any card between 2GB and 16GB. Note that if your card is Class 4 or 6 the Linux performance will suffer.
First we have to make the correct card partitions, this is done with fdisk.
Plug SD card into your SD card reader and enter in the terminal
# ls /dev/sd
Then press two times <TAB> you will see a list of your sd devices like sda sdb sdc note that some of these devices may be your hard disk so make sure you know which one is your sd card before you proceed as you can damage your HDD if you choose the wrong sd-device. You can do this by unplugging your sd card reader and identify which sd devices remove from the list.
Once you know which device is your sdcard like sda use this text instead of the sdX name in the references below:
# fdisk /dev/sdX
then do these steps:
will list your partitions
if there are already partitions on your card do:
2. d enter 1
if you have more than one partitition press d while delete them all
3. create the first partition, starting from 2048
n enter p enter 1 enter enter +16M
4. create second partition
n enter p enter 2 enter enter enter
then list the created partitions:
if you did everything correctly on 4GB card you should see something like:
Disk /dev/sdg: 3980 MB, 3980394496 bytes 123 heads, 62 sectors/track, 1019 cylinders, total 7774208 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x00000000 Device Boot Start End Blocks Id System /dev/sdg1 2048 34815 16384 83 Linux /dev/sdg2 34816 7774207 3869696 83 Linux
write changes to sd card
now we have to format the file system on the card:
the first partition should be vfat as this is FS which the Allwinner bootloader understands
# mkfs.vfat /dev/sdX1
the second should be normal Linux EXT3 FS
# mkfs.ext3 /dev/sdX2
5. Write the Uboot and sunxi-spl.bin
You should be in /home/user/A13-OLinuXino_kernel_34/# directory
Note that you have to write u-boot-sunxi-with-spl.bin in /dev/sdX (not sdX1 or sdX2)
# dd if=u-boot-sunxi/u-boot-sunxi-with-spl.bin of=/dev/sdX bs=1024 seek=8
6. Write kernel uImage you build to the SD-card
You should be in the directory below
# mount /dev/sdX1 /mnt/sd
copy the Kernel uImage to root directory in partition 1
# cp linux-sunxi/arch/arm/boot/uImage /mnt/sd
7. Write script.bin file
script.bin is a file with very important configuration parameters like port GPIO assignments, DDR memory parameters, Video resolution etc,
download the script.bin file
# cp script.bin /mnt/sd # sync # umount /dev/sdX1
8. Debian rootfs
The Linux Kernel and Uboot are ready, now we have need from Linux distribution rootfs.
Basically the only difference between the different Linux distributions is the rootfs, so if you put Debian rootfs you will have Debian, if you put Ubuntu rootfs it will be Ubuntu etc.
How to build one is a long topic, the good thing is that there are many already pre-built so we can just download one and use.
exit the kernel directory
# cd ..
You should be in the directory below
download debian rootfs a13_olinuxino_debian_fs_kernel_34_75.tgz
mount your sd card EXT3 FS partition:
# mkdir /mnt/sd # mount /dev/sdX2 /mnt/sd
and unarchive the rootfs
# tar xzvf a13_olinuxino_debian_fs_kernel_34_75.tgz -C /mnt/sd # ls /mnt/sd
the right result should be:
bin dev home lost+found mnt proc run selinux sys usr boot etc lib media opt root sbin srv tmp var
Now you have to replace the new generated kernel modules from /home/user/A13-OLinuXino_kernel_34/linux-sunxi/out/lib/modules/ to the new debian file system
# rm -rf /mnt/sd/lib/modules/* # cp -rfv linux-sunxi/out/lib/modules/3.x.xx+/ /mnt/sd/lib/modules/
where x.xx is the kernel version
in our case:
# cp -rfv linux-sunxi/out/lib/modules/3.4.75+/ /mnt/sd/lib/modules/ # sync # umount /mnt/sdX2
at this point you have Debian on your SD card second partition and
you have an SD card ready to boot debian on A13-OLinuXino
Connect USB-SERIAL-CABLE-F to UEXT Tx.Rx and GND, or connect a VGA screen. Put the SD-card in A10-OLinuXino-Micro and apply 5V power, you should see Uboot and then Kernel messages on the console
default username/password is : root / olimex
For these who do not want to go through all these steps the prebuilt image is linked on our A13-OLinuXino WiKi page.