What is CAF ?

CAF or Code Aurora Forums, hosts the source code for various Qualcomm® Snapdragon™ SoCs. It also serves as a staging area for open source code that is submitted to various upstream projects such as the Linux kernel and Android. These are tweaked sources of AOSP made to better compatibility and performance for their SoCs. Qualcomm MSM chips are the latest chips made for high end phones.

This is what OEMs use to make builds on top of CAFs source which uses Qualcomm’s chipsets.

Qualcomm refers Android for MSM as HLOS (High Level Operating System) Qualcomm® Snapdragon™ chipsets

Android Releases (HLOS)

These Releases are maintained by qcom for various Android versions and Kernel versions.

These Releases are separated into 2 parts and needs to be downloaded separately

1. Open-Source from http://www.codeaurora.org
2. Proprietary: This contains proprietary source-code and blobs for APPS(application processor) and firmware images. ex. vendor/qcom/proprietary

We can find this list of Tags and Releases at

Android releases - https://wiki.codeaurora.org/xwiki/bin/QAEP/release

Proprietary - https://chipcode.qti.qualcomm.com/

How to Read Tags and Build Ids

Each Tag/Build ID is identified by a unique Build identification code:

<PL_Image>-<Version>-<Chipset>

This Tags can then be used to get open source release manifest from Android releases

Downloading OSS HLOS manifest

Initialize the repo.

repo init -u git://codeaurora.org/platform/manifest.git -b release -m [manifest]

And then sync it as you’ll always do.

repo sync --no-clone-bundle --optimized-fetch

References:

1. https://developer.qualcomm.com/download/db410c/linux-android-software-build-and-installation-guide.pdf
2. https://wiki.codeaurora.org/xwiki/bin/QAEP/release