Linux and u-boot sources

The Linux kernel sources for the BeagleBoard, BeagleBoard-xM and BeagleBone are maintained on Github.com/BeagleBoard. The U-Boot bootloader sources maintained as part of the U-Boot mainline on git.denx.de.

The production and validation of these kernels is done with the Angstrom Distribution and meta-beagleboard with the OpenEmbedded build system. The sources shared here are done for convenience for those familiar with the git version control system.

For instructions on building for the Debian system (armhf) using an Ubuntu 12.04 host system, see this blog post.

Example for installing toolchain

~$ wget http://www.angstrom-distribution.org/toolchains/angstrom-2011.03-x86_64-linux-armv7a-linux-gnueabi-toolchain-qte-4.6.3.tar.bz2
~$ sudo tar -C / -xjf angstrom-2011.03-x86_64-linux-armv7a-linux-gnueabi-toolchain-qte-4.6.3.tar.bz2
~$ export PATH=/usr/local/angstrom/arm/bin:$PATH
 

Example build procedure for BeagleBone MLO and u-boot

~$ git clone git://git.denx.de/u-boot.git && cd u-boot
~/u-boot$ CROSS_COMPILE=arm-angstrom-linux-gnueabi- make am335x_evm
 

Example build procedure for BeagleBone 3.8-rcX kernel

~$ git clone git://github.com/beagleboard/kernel.git && cd kernel
~/kernel$ git checkout 3.8
~/kernel$ ./patch.sh
~/kernel$ cp configs/beaglebone kernel/arch/arm/configs/beaglebone_defconfig
~/kernel$ wget http://arago-project.org/git/projects/?p=am33x-cm3.git\;a=blob_plain\;f=bin/am335x-pm-firmware.bin\;hb=HEAD -O kernel/firmware/am335x-pm-firmware.bin
~/kernel$ cd kernel
~/kernel/kernel$ mkdir rootfs
~/kernel/kernel$ make ARCH=arm CROSS_COMPILE=arm-angstrom-linux-gnueabi- beaglebone_defconfig
~/kernel/kernel$ make ARCH=arm CROSS_COMPILE=arm-angstrom-linux-gnueabi- -j4 uImage dtbs
~/kernel/kernel$ make ARCH=arm CROSS_COMPILE=arm-angstrom-linux-gnueabi- -j4 modules
~/kernel/kernel$ make ARCH=arm CROSS_COMPILE=arm-angstrom-linux-gnueabi- INSTALL_MOD_PATH=$HOME/kernel/kernel/rootfs modules_install
~/kernel/kernel$ make ARCH=arm CROSS_COMPILE=arm-angstrom-linux-gnueabi- uImage-dtb.am335x-bone
~/kernel/kernel$ make ARCH=arm CROSS_COMPILE=arm-angstrom-linux-gnueabi- uImage-dtb.am335x-boneblack
 

Building a kernel module

I applied this patch and that provided the following files:

~/kernel/kernel/hello/hello.c

#include        /* Needed by all modules */
#include        /* Needed for KERN_INFO */
#include          /* Needed for the macros */

static int __init hello_start(void)
{
    printk(KERN_INFO "Loading hello module...\n");
    printk(KERN_INFO "Hello world\n");
    return 0;
}

static void __exit hello_end(void)
{
    printk(KERN_INFO "Goodbye Mr.\n");
}

module_init(hello_start);
module_exit(hello_end);
 

~/kernel/kernel/hello/Makefile

obj-m := hello.o

PWD   := $(shell pwd)
KDIR  := ${PWD}/..

default:
    make -C $(KDIR) SUBDIRS=$(PWD) modules
 

~/kernel/kernel$ cd hello
~/kernel/kernel/hello$ make ARCH=arm CROSS_COMPILE=arm-angstrom-linux-gnueabi- 
 

Last updated by jkridner.wordpress.com on Tue Nov 18 2014 15:02:48 GMT-0000 (UTC).

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