Ubuntu Phone EngineeringThe Phone Delivery Team

2014-04-30 edited. (2014-04-09) Rex Tsai <rex.tsai@canonical.com>© 2014 Canonical Ltd. Ubuntu and Canonical are registered trademarks of Canonical Ltd.

Architecture overview

Ubuntu Stack

High level architecture using ARM or x86 Android chipset

Using Android BSP

We recommend choosing a stable and proven hardware platform

Hardware bring up and validation significantly shortened due to common architecture

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Apps Scopes Shell, Home

Linux Kernel

Ubuntu PlatformLibraries: OpenGL ES, WiFi, Sensors

Unity 8, QT, Application Services

AAL

Android Devices Drivers

Hardware enablement

Boot process

Stages1. Kernel enablement & Ubuntu core.

○ A busybox shell through adb console

○ Test disk I/O using gzip compression/decompression on various partitions. This process can help find driver level errors

2. Integrate LXC & Android system service.○ A Ubuntu prompt through adb, and

LXC is running properly○ Observe upstart-property-watcher

running in the background3. Full system integration.

○ Ubuntu Unity UI appears on the screen

○ Start verifying higher level functionality such as Wifi, telephony, etc.

Image Components

Device tarballThe Device tarball contains the Ubuntu equivalent of an Android BSP. Each individual mobile device will have its own specific device tarball.

Ubuntu tarballThe Ubuntu tarball is considered the “standard” Ubuntu Touch image. As much as possible, it is common across all Ubuntu Touch devices. This design helps to prevent fragmentation of deployed devices.

Custom tarballThe Custom tarball is the officially supported method for all Ubuntu Touch downstream consumers, ranging from commercial OEMs to community remixes, to modify the look, feel, and behavior of Ubuntu Touch.

Deployment

Images○ Boot image

This is flashed to the boot partition and is given control by the bootloader in ROM. This is a device dependent image containing the kernel and the initramfs needed to boot Ubuntu. The initramfs userland bits follow the armhf ABI since it is built from Ubuntu sources. The kernel is ABI agnostic since it does not use floating point functionality.

○ Recovery (Clockworkmod Recovery image)Optional for running the device but necessary for OTA upgrades and also usually a good first step when porting Android to a device. This is a Clockworkmod Recovery image with Ubuntu patches, so it is built from the Android tree. git://phablet.ubuntu.com/CyanogenMod/android_bootable_recovery

○ System images This is built from the Android source tree and contains only the bare minimum needed for Ubuntu (Android HAL, initramfs, bionic, vendor blobs and daemons). Building Android apps, assets and the Dalvik runtime are disabled among other things.This image is mounted inside an LXC container in the Ubuntu host filesystem and it contains the Android proprietary drivers and is running the Android helper daemons needed to have proper support for all the hardware peripherals that are not natively supported by Ubuntu and open source drivers. Executables in this image use the armel ABI.

○ The Ubuntu root file system imageThis is a device independent image containing the Ubuntu Touch userland, the closes equivalent to a regular Ubuntu Desktop filesystem. This gets booted to, and in turn mounts and runs the Android system image inside an LXC container. This is built from the official Ubuntu package archives and by adding a few prebuilt Click packages.

Deploying Ubuntu systemRecovery utils

● ubuntu-device-flash (lp:/ubuntu/goget-ubuntu-touch)○ File upload & config protocol - adb

Recovery system○ based on CWM.○ adb is always on.○ system-image-upgrader

■ /cache● Read restore script from /cache/recovery/ubuntu_command

○ GPG verification■ archive-master.tar.xz■ archive-master.tar.xz.asc

Easy customization of look, feel, and behavior

Image Components

Device tarballThe Device tarball contains the Ubuntu equivalent of an Android BSP. Each individual mobile device will have its own specific device tarball.

Ubuntu tarballThe Ubuntu tarball is considered the “standard” Ubuntu Touch image. As much as possible, it is common across all Ubuntu Touch devices. This design helps to prevent fragmentation of deployed devices.

Custom tarballThe Custom tarball is the officially supported method for all Ubuntu Touch downstream consumers, ranging from commercial OEMs to community remixes, to modify the look, feel, and behavior of Ubuntu Touch.

Customization

● BackgroundsNormal Unity Shell background and the Welcome Screen background.○ Shell background○ Welcome Screen background

● Color Schemes○ Customized themes○ Infographic color scheme

the series of circles on the Welcome Screen that displays user’s data● Audio● Default Browser settings

○ Bookmarks○ home page

● Preinstalling Content○ click packages○ sample content.

Scope

Developers have multiple entry points on Ubuntu

ScopesC++ backend code (no UI)

Lowest effort

Greatest visibility

HTML5

Native/QMLDeclarative Language (C++ optional)

Great developer support/Documentation (Digia)

High Developer productivity

Aligned with HTML5 developer critical mass :

• Chrome, Android, iOS

• Webkit/Blink rendering engine

• Apache/Cordova API for offline

Scopes terminologyScopeThe search engine itself, talking to a web service or a local database. Its visible representation is a Dash page.

Standalone scopeA scope that presents a single set of results and queries one single source

Aggregating scopeA scope that acts as a container for multiple standalone scopes. Every scope can be an aggregating scope, which enable richer content on their Dash pages

Dash pageThe visible part of the scope: dash pages present the scope’s search interface and its results. Dash pages can be marked as favourites, so that they are always pinned in the Dash.

Ubuntu is designed to allow for OEM and Operator differentiation, at the default service layer, without fragmentation

Ubuntu enables partners to build their own footprint on Ubuntu devices, creating a rich core OS experience with scopes

Unprecedented customization capabilities in comparison to Android and other platforms:

● user account - own user identity

● default UX - with scopes and default apps

● branding and theming - own visual identity

● backend integration -i.e. carrier billing

Differentiate where it matters with Ubuntu

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Scopes are a a UI toolkit to present local or remote content and services in the home screen

Differentiate your device with scopes to deliver your own default experience

Discoverability of apps, services and content from multiple sources:

● users are no longer forced to decide which store to use

● users can focus on finding content quickly

Scopes | A New UI ParadigmA user experience where content is front and center

Scopes are fast and engaging Scopes are a fast and engaging way to embed your services in Ubuntu

Self Service Deal finder LBS Service

Scopes expose content and services in a rich and engaging way - allowing OEMs and Operators to differentiate their offerings in an unprecedented fashion.

Scopes are the tool that defines the core OS experience delivering content as part of the device UI - a direct channel to the user.

● The default pages use Scopes to deliver music, video and apps curated from a number of different sources.

● A scope can deliver information and content to existing pages or can exist as dedicated device pages.

● Harness the power of Scopes to mix and match a variety of content to create targeted services (e.g. dedicated pages for sports fans, city guides, operator self-service etc.)

● Scopes are a breeze to develop. Through a common UI toolkit, pages are easy to design and layout and the results are always elegant.

Scopes explained

Scopes registry

Scopes data flow

References● Ubuntu Developer http://developer.ubuntu.com/

○ Scope http://developer.ubuntu.com/scopes/overview/● Mir: Welcome to Mir http://unity.ubuntu.com/mir/● Touch - Ubuntu Wiki https://wiki.ubuntu.com/Touch

○ Touch/Porting https://wiki.ubuntu.com/Touch/Porting○ Touch/Deploying https://wiki.ubuntu.com/Touch/Deploying

● OEM Customization http://developer.ubuntu.com/resources/oem/○ Ubuntu Image Architecture http://developer.ubuntu.com/resources/oem/architecture/