The Emcraft Linux Vybrid software development environment makes use of a Yocto-based software distribution and development environment based on a modified ELDK software distribution developed by DENX Software Engineering (www.denx.de). The Yocto distribution includes the GNU cross development tools as well as a large number of pre-built and packaged Linux tools and libraries ready for immediate use on Cortex-A5.

In strict compliance with the GPL and related licenses, the Yocto distribution is provided by Emcraft with full source code, including all patches, extensions, programs and scripts used to build the distribution for Cortex-A5.

Typically, our users just proceed to deploy the prebuilt Yocto packages on the target, however if you need to rebuild the entire distribution, this application note explains how to do that.

Note: The Yocto distirbution is built by Emcraft on a Fedora-17 Linux development host. The procedure may work on other Fedora environments, however some porting changes may be needed. Specifically, the procedure is known to fail on Fedora-19 and subsequent Fedora releases.

Note: You will require 80+ Gbytes of free disk space on the Linux development host in order to run the build procedure.

Perform the Yocto build procedure as follows:

• Download the eldk-5.3-emcraft.tgz file from Emcraft-ELDK to an arbitrary directory on your development host and unpack this file.
• Change to the eldk directory.
• Run the following command. The last argument is the build directory. You can change that to an arbitrary directory on your build host. The script will create it if it does not exist yet:

TEMPLATECONF=meta-eldk/conf source oe-init-build-env /work/eldk-5.3-build

• After the command above has completed, you will be in the /work/eldk-5.3-build directory. Open conf/local.conf in a text editor and adjust the DL_DIR variable to a directory where you want the downloads to be placed. By default, that directory will be created in the build directory (/work/eldk-5.3-build). For different builds, consider placing the downloads in separate directories.
• Run the following command in order to perform the Yocto build:

bitbake core-image-qte-sdk meta-toolchain-qte

• In 3-5 hours (depending on the host capabilities) the resultant images will be as follows created as follows:

tmp/deploy/images/core-image-java-qte-sdk-generic-armv7a.tar.gz
tmp/deploy/sdk/eldk-eglibc-i686-arm-toolchain-qte-5.3.sh

Also, individual Qt ARM packages will be placed here:

tmp/deploy/ipk/armv7a-vfp-neon/qt*

• To install the images, refer to the VF6 SOM Starter Kit Guide, Section 7.1:
• After installing to /opt/eldk-5.3-vybrid, create a symlink as follows:

/opt/eldk-5.3 -> /opt/eldk-5.3-vybrid