Kernel Build - Revision history

Ashcharles at 23:36, 1 April 2016

2016-04-01T23:36:18Z

Conor O'Rourke at 12:14, 25 November 2013

2013-11-25T12:14:27Z

Conor O'Rourke: Add U-Boot details

2013-11-25T12:13:31Z

Add U-Boot details

Conor O'Rourke at 11:16, 19 November 2013

2013-11-19T11:16:15Z

Conor O'Rourke at 11:15, 19 November 2013

2013-11-19T11:15:46Z

Conor O'Rourke: Main website is up to date so just add hints and tips to this entry

2013-11-19T11:14:39Z

Main website is up to date so just add hints and tips to this entry

Dan Nelson at 07:48, 11 April 2012

2012-04-11T07:48:28Z

Dan Nelson: Created page with "11 April 2012 This wiki entry explains how to build the Gumstix Linux kernel from source. Start by installing the [http://wiki.gumstix.org/index.php?title=Toolchain toolchain]...."

2012-04-11T07:34:23Z

Created page with "11 April 2012 This wiki entry explains how to build the Gumstix Linux kernel from source. Start by installing the [http://wiki.gumstix.org/index.php?title=Toolchain toolchain]...."

New page

11 April 2012

This wiki entry explains how to build the Gumstix Linux kernel from source.

Start by installing the [http://wiki.gumstix.org/index.php?title=Toolchain toolchain].

You will also need the U-boot 'mkimage' utility. Debian and Ubuntu users can install it from their respective repositories. It's also compiled when U-boot is built if you can't get it otherwise. On top of that you will need 'git' and 'make'.
$ sudo apt-get install uboot-mkimage git make

Next we need to get the patched kernel source that's available at www.sakoman.com.
You can browse Sakoman's git repository [http://www.sakoman.com/cgi-bin/gitweb.cgi?p=linux-omap-2.6.git;a=summary here].

Decide where you want your kernel source to go an move to that directory. Then use git to download it.
$ git clone git://www.sakoman.com/git/linux-omap-2.6 linux -b omap-3.2

The above command pulls down the omap-3.2 branch. The omap-2.6.38 branch has proved stable for those who want to use Xenomai. Once the above process is complete move into the new directory. The first thing to do is to create a .config file.
$ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- omap3_defconfig (or maybe omap2plus_defconfig)

If you need to configure the kernel:
$ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- menuconfig

And now for the main kernel build.
$ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- uImage -j4

When the above completes, uImage can be found in arch/arm/boot/

Build the kernel modules.
$ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- modules -j4

To install your kernel modules into your root file system:
$ make ARCH=arm modules_install INSTALL_MOD_PATH=/path-to-your-rootfs/

← Older revision		Revision as of 23:36, 1 April 2016
Line 1:		Line 1:
−	This wiki entry ~~adds a few~~ details on building the Gumstix Linux kernel and bootloader from source.	+	There are [https://github.com/gumstix/yocto-manifest/wiki/Kernel,-Device-Tree-and-u-boot updated instructions] for standalone compilation of u-boot and linux. Yocto users may also find [https://github.com/gumstix/yocto-manifest/wiki/Kernel-Compilation this] useful.
		+
		+	This wiki entry has some older details on building the Gumstix Linux kernel and bootloader from source.

	Start by installing the [http://wiki.gumstix.org/index.php?title=Toolchain toolchain].		Start by installing the [http://wiki.gumstix.org/index.php?title=Toolchain toolchain].

@@ Line 42: / Line 42: @@
 You can override the version modification by setting LOCALVERSION (to anything) before running make.
-=== U-Boot ===
 The source for U-Boot is held in [https://github.com/gumstix/u-boot github]. The branch that the Yocto recipes are using is currently 2013.07 (although there is a 2013.10 branch too). You can checkout the branch with:

@@ Line 1: / Line 1: @@
-This wiki entry adds a few details on building the Gumstix Linux kernel from source.
+This wiki entry adds a few details on building the Gumstix Linux kernel and bootloader from source.
 Start by installing the [http://wiki.gumstix.org/index.php?title=Toolchain toolchain].
@@ Line 10: / Line 10: @@
 The most usual way to pull the source code is using git:
-  $ git clone --branch omap-3.6 git://github.com/gumstix/linux.git Linux
+  $ git clone --branch omap-3.6 git://github.com/gumstix/linux.git linux
-will clone the entire source tree to your machine and checkout the omap-3.6 branch into the "linux" directory. There are plenty of guides online to using git but a few timesaving methods are worth mentioning:
+will clone the entire source tree to your machine and checkout the omap-3.6 branch into the "linux" directory. You can also use <tt>https</tt> instead of <tt>git</tt>. There are plenty of guides online to using git but a few timesaving methods are worth mentioning:
 === Cloning a shallow tree ===
@@ Line 41: / Line 41: @@
 You can override the version modification by setting LOCALVERSION (to anything) before running make.

@@ Line 30: / Line 30: @@
 For the 3.6 branch, this will pull approximately 123MB from the github server.
-== Subtleties ===
+=== Subtleties ===
 There is absolutely no difference in result aside from the presence of the ".git" directory, but this has a few subtle consequences. If you build with the zip file, you will get kernel and module versions stamped "3.6.0". If you build from the git repository, the make process:

@@ Line 28: / Line 28: @@
 (this will do a 301 redirect so be aware of this - you might get a very small file with html in it!)
-For the 3.6 branch, this will and pull approximately 123MB from the github server.
+For the 3.6 branch, this will pull approximately 123MB from the github server.
 There is absolutely no difference in result aside from the presence of the ".git" directory, but this has a few subtle consequences. If you build with the zip file, you will get kernel and module versions stamped "3.6.0". If you build from the git repository, the make process:

@@ Line 1: / Line 1: @@
-April 2012
+This wiki entry adds a few details on building the Gumstix Linux kernel from source.
-−
-This wiki entry explains how to build the Gumstix Linux kernel from source.
 Start by installing the [http://wiki.gumstix.org/index.php?title=Toolchain toolchain].
@@ Line 8: / Line 6: @@
   $ sudo apt-get install uboot-mkimage git make
-Next we need to get the patched kernel source that's available at www.sakoman.com.
+The official kernel build [http://gumstix.org/basic-cross-compilation.html instructions] are the best source to describe building a kernel and are up to date. The gumstix kernels are stored on [https://github.com/gumstix/linux github] and are in different branches for differing platforms. There is a table of branches against platforms on the [http://gumstix.org/access-source-code.html gumstix.org website].
-You can browse Sakoman's git repository [http://www.sakoman.com/cgi-bin/gitweb.cgi?p=linux-omap-2.6.git;a=summary here].
-Decide where you want your kernel source to go an move to that directory.  Then use git to download it.
+  <nowiki>$ wget https://github.com/gumstix/linux/archive/omap-3.6.zip</nowiki>
- $ git clone git://www.sakoman.com/git/linux-omap-2.6 linux -b omap-3.2
-The above command pulls down the omap-3.2 branch.  The omap-2.6.38 branch has proved stable for those who want to use Xenomai.  Once the above process is complete move into the new directory.  The first thing to do is to create a .config file.
+(this will do a 301 redirect so be aware of this - you might get a very small file with html in it!)
- $ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- omap2plus_defconfig (or maybe omap3_defconfig)
-If you need to configure the kernel:
+For the 3.6 branch, this will and pull approximately 123MB from the github server.
- $ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- menuconfig
-And now for the main kernel build.
+There is absolutely no difference in result aside from the presence of the ".git" directory, but this has a few subtle consequences. If you build with the zip file, you will get kernel and module versions stamped "3.6.0". If you build from the git repository, the make process:
- $ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- uImage -j4
-When the above completes, uImage can be found in arch/arm/boot/
+* detects the git repository presence
-Build the kernel modules.
+Thus you will get kernel and module version stamped with "3.6.0+". If you try and load a 3.6.0+ module into a 3.6.0 kernel, it will fail with an "invalid module format" error. You can force it with "modprobe -f" but that isn't really a recommended action generally. The normal procedure is to install the kernel and modules together (see the [http://gumstix.org/basic-cross-compilation.html website] for details.
- $ make ARCH=arm CROSS_COMPILE=arm-linux-gnueabi- modules -j4
-To install your kernel modules into your root file system:
+You can override the version modification by setting LOCALVERSION (to anything) before running make.
- $ make ARCH=arm modules_install INSTALL_MOD_PATH=/path-to-your-rootfs/