Building the Yocto BSP (XUELK)

Info Box Applies to AXEL ULite Applies to SBC Lynx Applies to Yocto

As the XELK kit is based on Yocto, the implementation of the MVM follows the approach described here. As such, the reading of this section is highly recommended.

History

Version	Date	XUELK version	Notes
1.0.0	December 2016	XUELK 1.1.0
1.2.0	May 2017	XUELK 1.2.0
2.0.0	Sep 2017	XUELK 2.0.0

Quick reference

Repository Information

Repository	BSP Manifest	Yocto BSP Layer
URL	git@git.dave.eu:lynx/lynx-bsp.git	git@git.dave.eu:lynx/meta-lynx.git
stable branch	lynx-krogoth	lynx-krogoth
stable tag	xuelk-2.0.2	xuelk-2.0.2

Build targets

Name	Description
lynx-image-qt5	QT5.x support
lynx-image-devel	minimal for development/debugging image
lynx-image-networking	based on lynx-image-devel plus networking tools
lynx-image-core	minimal working image with SSH
lynx-image-gui	based on lynx-image-core with additional tools to support the graphical environment

Introduction

This is a quickstart guide to build Yocto BSP for Axel ULite SOM and SBC Lynx, to rebuild the binaries (u-boot, linux kernel, root file system) provided with XUELK releases.

For more information regarding Yocto build system, go to its dedicated category page

Build System prerequisites

XUELK MVM is already configured to build this Yocto version/configuration, however, users typically don't use a VirtualBox VM for Yocto builds for performance reasons.

You can refer to Yocto manual setup section for a list of supported Linux distribution and their configuration to create your own build environment on your favorite distribution.

Build the XUELK Yocto BSP

Initialize the build environment

XUELK Yocto BSP uses git-repo tool to fetch all the required git repositories to build

dvdk@dvdk-vm:~/lynx$ curl http://commondatastorage.googleapis.com/git-repo-downloads/repo > repo
dvdk@dvdk-vm:~/lynx$ chmod a+x repo
dvdk@dvdk-vm:~/lynx$ ./repo init -u git@git.dave.eu:lynx/lynx-bsp.git -b lynx-krogoth
dvdk@dvdk-vm:~/lynx$ ./repo sync

Build the Yocto BSP image

Please note that even the basic root file system requires a few hours to build on a mid/hi range desktop (4-6 cores, 8-12 GiB RAM) also depending on your Internet connection speed (all sources are fetched from the network). Nearly 20GiB of disk space is required for the build. Moreover, building inside the DVDK adds some overhead, since the performances of a virtual machine are reduced if compared to the physical hardware. Thus, it's recommended to check the hardware capabilities of the host system and, when building with Yocto is required, developers should consider the following options:

• migrating the build system to a physical machine
• assuming that the host system has the required resources, extending the hardware capabilities of the default DVDK (eg: adding more cores and disk space)

Once completed the initialization phase, developers can launch the Yocto image build process with the following commands:

dvdk@dvdk-vm:~/lynx$ DISTRO=fsl-imx-fb MACHINE=sbc-lynx source lynx-setup-release.sh -b build
dvdk@dvdk-vm:~/lynx/build$ bitbake lynx-image-networking

The resulting files (kernel, devicetree and u-boot binaries, plus .tar.gz root file system) will then be available inside build/tmp/deploy/images/sbc-lynx.

Generating the SDKs

After creating an image as described above, the corresponding SDK can be generated by issuing the following command:

bitbake <target-image-name> -c populate-sdk

Again, replace <target-image-name> with one of the images listed in here.

Build additional packages

To build additional packages the user must first enter the directory where the lynx-setup-release.sh is placed and source it

dvdk@dvdk-vm:~/lynx$ DISTRO=fsl-imx-fb MACHINE=sbc-lynx source lynx-setup-release.sh -b build
dvdk@dvdk-vm:~/lynx/build$

And then he can run any of the bitbake commands.

dvdk@dvdk-vm:~/lynx/build$ bitbake memtester

The resulting packages (the default format is ipk) can be found inside build/tmp/deploy/rpm.

dvdk@dvdk-vm:~/lynx/build$ ls -l tmp/deploy/rpm/cortexa7hf_vfp_neon/memtester*
-rw-r--r-- 1 dvdk dvdk  9967 Sep  7 05:43 tmp/deploy/rpm/cortexa7hf_vfp_neon/memtester-4.1.3-r0.cortexa7hf_vfp_neon.rpm
-rw-r--r-- 1 dvdk dvdk 25544 Sep  7 05:43 tmp/deploy/rpm/cortexa7hf_vfp_neon/memtester-dbg-4.1.3-r0.cortexa7hf_vfp_neon.rpm
-rw-r--r-- 1 dvdk dvdk  2884 Sep  7 05:42 tmp/deploy/rpm/cortexa7hf_vfp_neon/memtester-dev-4.1.3-r0.cortexa7hf_vfp_neon.rpm
-rw-r--r-- 1 dvdk dvdk  5611 Sep  7 05:44 tmp/deploy/rpm/cortexa7hf_vfp_neon/memtester-doc-4.1.3-r0.cortexa7hf_vfp_neon.rpm