HKG15-506: Comcast - Lessons learned from migrating the RDK code base to the OpenEmbedded/Yocto build framework --------------------------------------------------- Speaker: SANJAY DORAIRAJ, KHEM RAJ Date: February 13, 2015 --------------------------------------------------- ★ Session Summary ★ This session will cover Comcast’s experience of migrating RDK to the OpenEmbedded build framework. It will cover the porting of Comcast specific devices and the impact on the software design, as well as what was involved in porting efforts - both good and bad. Attendees will be able to gather a list of best practices for OE and a concrete list of steps for RDK when porting to new devices or doing development with the RDK platform. In addition it will cover some of the more pressing issues and challenges and how Comcast solved some of the problems e.g. developer workflow, continuous integration and delivery -------------------------------------------------- ★ Resources ★ Pathable: https://hkg15.pathable.com/meetings/250852 Video: https://www.youtube.com/watch?v=RIGpastAifg Etherpad: http://pad.linaro.org/p/hkg15-502 --------------------------------------------------- ★ Event Details ★ Linaro Connect Hong Kong 2015 - #HKG15 February 9-13th, 2015 Regal Airport Hotel Hong Kong Airport --------------------------------------------------- http://www.linaro.org http://connect.linaro.org

1. Presented by
Date
RDK Migration to Yocto/OE
Lessons Learned
Khem Raj
Sanjay Dorairaj
February 13th 2015

2. Topics
● RDK Overview
● RDK Software Stack
● Legacy Build Framework
● Challenges with the legacy build framework
● Moving to Yocto/OE – What was involved?
● Challenges with Yocto/OE
● Tools
● Coming Soon…

3. RDK Overview
• RDK – Reference Design Kit for set-tops
• Development started in 2012
• Managed by RDK-LLC and licensed to a community of
close to 200 members
• Linux based software stack
• Platform for the Comcast X1 experience and deployed on
more than 5 million set-tops

4. RDK Software Stack

5. Motivation & Technical Aspects
of the legacy build framework
● Motivation
o Orchestration framework to build RDK-based binary distributions
o Component level build scripts
o Allow for strict access control policies at multiple granularities
o Separation of fetch & build processes
● Technical aspects
o Written using Python
o SVN/Git using Gclient
o Nexus Repository for binary artifacts

6. Legacy build framework

7. Challenges with legacy build
system
● Scalability
● Maintainability
● Standards Compliance
● Build consistency
● Build performance
● Collaboration
● Documentation & Knowledge base
● Proven build system
● Common framework

8. Move to Yocto/OE
- What was involved?
● Layered Architecture
● Repository Structure
● Repo integration
● Autotools/Bitbake Migration
● Binary Management
● sstate cache
● Component refactoring
● Development workflow
● Release workflow
● Firmware nomenclature
● Code size optimization
● Training & Documentation

9. Challenges with Yocto/OE
● Developer workflow
● Resource intensive
● Enhanced prebuilt support
● Paradigm shift in development – bitbake, Git, patch management
● Adoption challenges
● Upstreaming
● Component Yocto’ization

10. Tools
● Git/Gerrit Integration
● Nexus Repository for binary management
● Jenkins for build orchestration
● RDK Portal – centralized dashboard and build status aggregator
● Cache – sstate/opensource
● AWS and Openstack server farm
● Automated Test and Coverity Integration
● Gerrit Dashboard
● Changes Management
● Release Management

11. Coming soon…
● Upgrade to Yocto 1.8
● Bitbake optimization
● Locked sstate support
● Workflow refinements
● Toaster integration
● More architecture support – ARM, MIPS,x86 (aarch64?)
● Tools 2.0