Yocto project – Building Embedded Linux

In this course Beaglebone Black is used as a target platform. It is one of the most popular low-cost, community-supported development platform for developers and hobbyists.

It has got AM335x 1GHz ARM® Cortex-A8 processor with software compatibility with most of the popular Linux distributions (ex: Ubuntu). However learnings from these courses can be applied in any standard or customized target platform which is capable of running Embedded Linux.

Yes. You will create a custom distribution and boot it up in the Beagle Bone Black as the target hardware.

Knowing buildroot would be an added advantage for this course. However in this course you will be learning some of the unique features of Yocto using which you can create your own Linux distribution faster and easier. One of key element you will learn is about automating the build by writing the recipes.

Yes. You will get to learn this.

Participants need to have following prerequisites to take up this course.

• Familiar with the UNIX or Linux command line interface
• Scripting
• Python(Added Advantage)
• Embedded Linux

• The Yocto Project is an open source collaboration project that provides templates, tools and methods to help you create custom Linux-based systems for embedded products regardless of the hardware architecture.
• Unlike build systems based on shell scripts or makefiles, the Yocto Project automates how source is fetched from a variety of upstream sources or from local project repositories.
• Existing embedded developers have many systems from which to choose. Once a system is chosen and a device's OS has been created, it can often be very difficult and time consuming to trim the distribution to an appropriate footprint size and assemble a working set of components.
• Then, for the developer’s next project, if updated components are needed, perhaps for bug fixes, security fixes, or new hardware support, the developer typically must start over, with little ability to re-use prior work on distributions.
• The Yocto Project solves these problems by providing a single focus for embedded development, requiring less time to get a working and up-to-date distribution together. In addition, if commercial support is desired, it is quite simple to transition to a supporting operating system vendor (OSV) who offers products and services compatible with the Yocto Project. All of the major embedded Linux OSVs are active members of the Yocto Project.

There are many advantages of using Yocto, which are mentioned below.

• Highly Customizable: It has a powerful customization architecture that allows the choice of a wide variety of footprint sizes as well as control over the choice or absence of components such as graphics subsystems, visualization middleware, and services. This helps you to create custom Linux distribution exactly as per your requirements.
• Package selection and compatibility: A complete set of Linux package versions is specified in the metadata for the project; these versions are known to work correctly together. A robust effort within the project is dedicated to keeping this selection of packages fresh and up-to-date. Unlike other systems, however, only a single version of each package is typically provided with the project at any given time. This ensures that the packages are known to work well together, while providing the freedom to replace them at any time as the needs of a given embedded project mature.
• Package and architecture Agnostic: Yocto Project is package-format agnostic - supporting both major Linux packaging systems (.rpm and .deb), as well as the embedded-friendly ipk format. The Yocto Project is also architecturally agnostic - supporting all major embedded architectures: ARM, 32- and 64-bit x86, PowerPC, and MIPS.
• Easy to get started: The Yocto Project shares the core build tool (BitBake) and metadata syntax with OpenEmbedded, particularly the core set of components known as openembedded-core. This commonality provides automatic familiarity for developers already using OpenEmbedded. However, the learning curve for getting started with the Yocto Project is less steep. It is easier for new users to create a working distribution with the Yocto Project, and more work is being done currently on this subject with the new Hob graphical user interface.
• SDK support: When a distribution is created with the Yocto Project, the build tool creates an application development SDK tailored to that distribution. This SDK can plug into the Eclipse IDE or it can be run as a command-line development system, complete with cross tools for the host and development tools for the device being developed.

Build Host: A build host with a minimum of 50 Gbytes of free disk space that is running a supported Linux distribution (i.e. recent releases of Fedora, openSUSE, CentOS, Debian, or Ubuntu).
Build Host Packages: Appropriate packages installed on the build host.
The Yocto Project team verifies each release against recent versions of the most popular Linux distributions that provide stable releases. In general, if you have the current release minus one of the following distributions, you should have no problems.

• Ubuntu
• Fedora
• openSUSE
• CentOS
• Debian

The OpenEmbedded build system should be able to run on any modern distribution that has the following versions for Git, tar, and Python.

• Git 1.8.3.1 or greater
• tar 1.27 or greater
• Python 3.4.0 or greater

One item that all build systems require is a toolchain: a compiler, assembler, linker, and other binary utilities necessary for creating binary executable files for a given architecture. Poky (reference distribution for Yocto project) uses the GNU Compiler Collection (GCC), but you can specify other toolchains as well.

Poky uses a technique known as cross-compilation: using a toolchain on one architecture to build binary executable files for a different architecture (for example, building an ARM distribution on an x86-based system). Developers often use cross-compilation in embedded systems development to take advantage of the host system's higher performance.

Refer to Yocto Documentation - Workflow section to get all details about workflows in Yocto.

Linux Internals & Networking workshop is conducted on two consecutive weekends. Contents are delivered in a workshop manner, which is power packed. However to realize the real benefit of this workshop, participants need to work on some real time projects / assignments to make the learning effective. In order to support this need, we provide one month lab assistance after the course. During this period our mentors will be providing you support when you are facing difficulty in building projects using Linux system calls. This includes debugging issues in pair or clarifying your doubts using our online ecosystem. This way your learning will be complete & effective.

Trainers (our mentors) for this workshop are professionals who have worked with various corporate organizations like Samsung, HP, Novell, Huawei etc, who bring in 12+ years of experience on average. Our mentors understand industry requirements very well in order to maximize the value. Added to that, our mentors are passionate about training, which enables you to write a device driver on your own by the end of the workshop.