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From AOSP to Android powered device
Ivan Pustovit
Senior Software Engineer

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Introduction

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Mobile OS chart
https://gs.statcounter.com/os-market-share/mobile/worldwide Oct 2018-Oct 2019

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Device zoo

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OmniROM LineageOS MIUI
CopperheadOS Paranoid Android AOKP Resurrection Remix OS
Replicant OxygenOS Pixel experience AOSP Extended
AOSP-based distributions
CyanogenMod

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Device production

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• Free for download
• More than 800 projects
• More than 50 GB of sources
Android Open Source Project (AOSP)

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device.mk
• Product packages
• Config files
• Features
• Properties
init.rc
sepolicy
Resource overlays
Configuration

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Resource flexibility

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Android architecture
System apps
Java Framework
Native C/C++
libs
Android
Runtime
HAL
Linux kernel
vintf
GOOGLE
VENDOR

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Hardware Abstraction Layer (HAL)
Wi-Fi Audio USB Broadcast Radio
Radio Media Graphics DRM
GPS Bluetooth Camera Keymaster

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Project Treble

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Project Treble

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Android partitions
System apps
Java Framework
Native C/C++
libs
Android
Runtime
HAL
Linux kernel
vintf
system
vendor
boot
bootloader
userdata
odm
product
Common
SoC specific
Product specific

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Installing system update...
Updates

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Before A/B updates
Current Android
version recovery
Before update
Current Android
version reboot
Recovery
/tmp
Next Android
version
/tmp
Next Android
version
After update
Flash
Next Android
version

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A/B Updates
Current
Android
version
Current
Android
version
Active
slot
Inactive
slot
A B
Current
Android
version
Next
Android
version
Active
slot
Inactive
slot
A B
Current
Android
version
Next
Android
version
Inactive
slot
Active
slot
A B
update_engine reboot
Before update After update After reboot

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What is Android?
AOSP GMS (Google mobile services)

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Google Mobile Services (GMS)

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Google certification

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Certification

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Android compatibility program
● The Android Compatibility program defines
technical details of the Android platform and
provides tools for OEMs to ensure developer
applications run on a variety of devices.
● The Android SDK provides built-in tools for
developers to clearly state the device features
required by their applications.
● Google Play shows applications only to those
devices that can properly run those
applications.

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The CDD represents the "policy" aspect of
Android compatibility.
This document enumerates the requirements
that must be met in order for devices to be
compatible with Android.
The CDD's role is to codify and clarify specific
requirements, and eliminate ambiguity.
Android Compatibility Definition Document (CDD)
AOSP CDD

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The CTS represents the "mechanism" of
compatibility.
The CTS is an automated testing suite that
uses two major software components:
• The CTS Trade Federation test harness
runs on your desktop machine and
manages test execution.
• Individual test cases are executed on the
DUT. The test cases are written in Java
as JUnit tests and packaged Android
.apk files to run on the actual device
target.
Compatibility Test Suite (CTS)
AOSP CDD CTS

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● Android 2.1 “Eclair”
>23k tests
...
● Android 6.0 “Marshmallow”
>254k tests
● Android 7.x “Nougat”
>440k tests
● Android 8.x “Oreo”
>620k tests
● Android 9.0 “Pie”
>946k tests
● Android 10.0 “Q”
>1M tests
Compatibility Test Suite(CTS)
AOSP CDD CTS

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CTS Verifier provides tests for APIs and
functions that cannot be tested on a stationary
device without manual input (e.g. audio
quality, accelerometer, etc).
The Compatibility Test Suite Verifier (CTS Verifier)
AOSP CDD CTS CTS Verifier

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The Vendor Test Suite (VTS) automates HAL and OS kernel
testing.
Validates that the HALs are written in a way consistent with the
interfaces with Android.
Vendor Test Suite (VTS)
AOSP CDD CTS CTS Verifier VTS

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The GMS Test Suite ensure that the Google Mobile
applications are compatible with the device.
GMS Test Suite (GTS)
AOSP CDD CTS CTS Verifier VTS GTS

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AOSP CDD CTS CTS Verifier VTS GTS Profit!
Certified

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Thank You!