Xiaomi Mi 8 Explorer Edition (ursa)

Xiaomi Mi 8 Explorer Edition (ursa)

Table of contents

Install LineageOS on ursa

Basic requirements

  1. Read through the instructions at least once before actually following them, so as to avoid any problems due to any missed steps!
  2. Make sure your computer has adb and fastboot. Setup instructions can be found here.
  3. Enable USB debugging on your device.
  4. Boot your device with the stock OS at least once and check every functionality.
    Make sure that you can send and receive SMS and place and receive calls (also via WiFi and LTE, if available), otherwise it won’t work on LineageOS either!
  5. LineageOS is provided as-is with no warranty. While we attempt to verify everything works you are installing this at your own risk!

Unlocking the bootloader

  1. Create a Mi account on Xiaomi’s website. Beware that one account is only allowed to unlock one unique device every 30 days.
  2. Add a phone number to your Mi account.
  3. Insert a SIM into your phone.
  4. Enable developer options in Settings > About Phone by repeatedly tapping MIUI Version.
  5. Link the device to your Mi account in Settings > Additional settings > Developer options > Mi Unlock status.
  6. Download the Mi Unlock app (Windows is required to run the app).
  7. Run the Mi Unlock app and follow the instructions provided by the app. It may tell you that you have to wait up to 30 days. If it does so, please wait the quoted amount of time before continuing to the next step!
  8. After device and Mi account are successfully verified, the bootloader should be unlocked.
  9. Since the device resets completely, you will need to re-enable USB debugging to continue.

Installing a custom recovery using fastboot

  1. Download Lineage Recovery. Simply download the latest recovery file, named something like lineage-19.1-20221007-recovery-ursa.img.
  2. Connect your device to your PC via USB.
  3. On the computer, open a command prompt (on Windows) or terminal (on Linux or macOS) window, and type: 
    adb reboot bootloader

    You can also boot into fastboot mode via a key combination:

    • With the device powered off, hold Volume Down + Power. Keep holding both buttons until the word “FASTBOOT” appears on the screen, then release.
  4. Once the device is in fastboot mode, verify your PC finds it by typing: 
    fastboot devices

    If you don’t get any output or an error:

    • on Windows: make sure the device appears in the device manager without a triangle. Try other drivers until the command above works!
    • on Linux or macOS: If you see no permissions fastboot try running fastboot as root. When the output is empty, check your USB cable and port!
  5. Flash recovery onto your device (replace <recovery_filename> with the actual filename!): 
    fastboot flash recovery <recovery_filename>.img
  6. Now reboot into recovery to verify the installation.
    Do not reboot into the existing OS, since it will overwrite the recovery you just installed!

    • With the device powered off, hold Volume Up + Power. Keep holding both buttons until the “Mi 8” logo appears on the screen, then release.

Installing LineageOS from recovery

  1. Download the LineageOS installation package that you would like to install or build the package yourself.
    • (Optionally): If you want to install an application package add-on such as Google Apps (use the arm64 architecture), please read and follow the instructions on Google Apps page
  2. If you are not in recovery, reboot into recovery:
    • With the device powered off, hold Volume Up + Power. Keep holding both buttons until the “Mi 8” logo appears on the screen, then release.
  3. Now tap Factory Reset, then Format data / factory reset and continue with the formatting process. This will remove encryption and delete all files stored in the internal storage, as well as format your cache partition (if you have one).
  4. Return to the main menu.
  5. Sideload the LineageOS .zip package:
    • On the device, select “Apply Update”, then “Apply from ADB” to begin sideload.
    • On the host machine, sideload the package using: adb sideload filename.zip.

  6. (Optionally): If you want to install any add-ons, repeat the sideload steps above for those packages in sequence.

  7. Once you have installed everything successfully, click the back arrow in the top left of the screen, then “Reboot system now”.

Update to a newer build of the same LineageOS version on ursa

Updating your device

Using the LineageOS Updater app

  1. Open Settings, navigate to “System”, then “Updater”.
  2. Click the Refresh Icon in the top right corner.
  3. Choose which update you’d like and press “Download”.
  4. When the download completes, click “Install”. Your device will reboot to recovery and install the update, then reboot to the updated installation.

From your PC via the push_update script (Linux/macOS only)

  1. Make sure your computer has working adb. Setup instructions can be found here.
  2. Enable USB debugging on your device. Additionally, open Settings, then “System”, then “Developer Options”, and then either check “Rooted Debugging” (LineageOS 17.1 or above) or select “Root Access Options”, then “ADB Only”.
  3. Run adb root

  4. Run wget https://raw.githubusercontent.com/LineageOS/android_packages_apps_Updater/lineage-19.1/push-update.sh && chmod +x push-update.sh

  5. Run: ./push-update.sh /path/to/zip
  6. Open Settings, navigate to “System”, then “Updater”. Then proceed to click “Install” on the newly pushed update to commence installation. Your device will reboot to recovery and install the update, then reboot to the updated installation.

Sideloading from Recovery

  1. Make sure your computer has working adb. Setup instructions can be found here.
  2. Enable USB debugging on your device. Additionally, open Settings, then “System”, then “Developer Options”, and then either check “Rooted Debugging” (LineageOS 17.1 or above) or select “Root Access Options”, then “ADB Only”.
  3. Run: adb reboot sideload

  4. Run: adb sideload /path/to/zip

  5. Click the back arrow in the top left of the screen, then “Reboot system now”.

Upgrade to a higher version of LineageOS (e.g. lineage-15.1 -> lineage-16.0) on ursa

Manually upgrading LineageOS

The updater app does not support upgrades from one version of LineageOS to another, and will block installation to any update for a different version. Upgrading manually requires similar steps to installing LineageOS for the first time.

  1. Verify your device is using the latest Lineage Recovery. Simply download the latest recovery file, named something like lineage-19.1-20221007-recovery-ursa.img.
    Follow your device’s installation guide to see how you can update your recovery image.

  2. Download the LineageOS install package that you’d like to install or build the package yourself.
  3. If you are currently using (or now want to use) an application package add-on such as Google Apps, you have the following options:
    • keep using them: Download the appropriate version now (use the arm64 architecture)
    • remove them: You can only do so by performing a factory reset, which will also remove all your data.
    • start using them: You can only do so by performing a factory reset, which will also remove all your data. Download the appropriate version now (use the arm64 architecture)
  4. Make sure your computer has working adb. Setup instructions can be found here.

  5. Enable USB debugging on your device.

  6. Run adb reboot sideload.
  7. Run adb sideload /path/to/zip (inserting the path to your LineageOS package).
  8. (Optionally): If you want to install any add-ons, click Apply Update, then Apply from ADB, then adb sideload /path/to/zip those packages in sequence.
  9. Once you have installed everything successfully, click the back arrow in the top left of the screen, then “Reboot system now”.

Build for ursa

Introduction

These instructions will hopefully assist you to start with a stock Xiaomi Mi 8 Explorer Edition, unlock the bootloader (if necessary), and then download
the required tools as well as the very latest source code for LineageOS (based on Google’s Android operating system) for your device. Using these, you can build both
a LineageOS installation zip and a LineageOS Recovery image and install them on your device.

It is difficult to say how much experience is necessary to follow these instructions. While this guide is certainly not for the extremely uninitiated,
these steps shouldn’t require a PhD in software development either. Some readers will have no difficulty and breeze through the steps easily.
Others may struggle over the most basic operation. Because people’s experiences, backgrounds, and intuitions differ, it may be a good idea to read through
just to ascertain whether you feel comfortable or are getting over your head.

Remember, you assume all risk of trying this, but you will reap the rewards! It’s pretty satisfying to boot into a fresh operating system you baked at home :).
And once you’re an Android-building ninja, there will be no more need to wait for “nightly” builds from anyone. You will have at your fingertips the skills to
build a full operating system from code and install it to a running device, whenever you want. Where you go from there– maybe you’ll add a feature, fix a bug, add a translation,
or use what you’ve learned to build a new app or port to a new device– or maybe you’ll never build again– it’s all really up to you.

What you’ll need

  • A Xiaomi Mi 8 Explorer Edition.
  • A relatively recent 64-bit computer:
    • Linux, macOS, or Windows – these instructions are only tested using Ubuntu LTS, so we recommend going with that.
    • A reasonable amount of RAM (16 GB to build up to lineage-17.1, 32 GB or more for lineage-18.1 and up). The less RAM you have, the longer the build will take. Enabling ZRAM can be helpful.
    • A reasonable amount of Storage (200 GB to build up to lineage-17.1, 300 GB for lineage-18.1 and up). You might require more free space for enabling ccache or building for multiple devices. Using SSDs results in considerably faster build times than traditional hard drives.
  • A decent internet connection and reliable electricity. 🙂
  • Some familiarity with basic Android operation and terminology.
    It may be useful to know some basic command line concepts such as cd, which stands for “change directory”, the concept of directory hierarchies, and that in Linux they are separated by /, etc.

Let’s begin!

Build LineageOS

Install the platform-tools

If you haven’t previously installed adb and fastboot, you can download them from Google.
Extract it running:

unzip platform-tools-latest-linux.zip -d ~

Now you have to add adb and fastboot to your PATH. Open ~/.profile and add the following:

# add Android SDK platform tools to path
if [ -d "$HOME/platform-tools" ] ; then
    PATH="$HOME/platform-tools:$PATH"
fi

Then, run source ~/.profile to update your environment.

Install the build packages

Several packages are needed to build LineageOS. You can install these using your distribution’s package manager.

To build LineageOS, you’ll need:

  • bc bison build-essential ccache curl flex g++-multilib gcc-multilib git gnupg gperf imagemagick
    lib32ncurses5-dev lib32readline-dev lib32z1-dev libelf-dev liblz4-tool libncurses5 libncurses5-dev
    libsdl1.2-dev libssl-dev libxml2 libxml2-utils lzop pngcrush rsync
    schedtool squashfs-tools xsltproc
    zip zlib1g-dev

For Ubuntu versions older than 20.04 (focal), install also:

  • libwxgtk3.0-dev

While for Ubuntu versions older than 16.04 (xenial), install:

  • libwxgtk2.8-dev

Java

Different versions of LineageOS require different JDK (Java Development Kit) versions.

  • LineageOS 18.1+: OpenJDK 11 (included in source download)
  • LineageOS 16.0-17.1: OpenJDK 1.9 (included in source download)
  • LineageOS 14.1-15.1: OpenJDK 1.8 (install openjdk-8-jdk)
  • LineageOS 11.0-13.0: OpenJDK 1.7 (install openjdk-7-jdk)*

* Ubuntu 16.04 and newer do not have OpenJDK 1.7 in the standard package repositories. See the Ask Ubuntu question “How do I install openjdk 7 on Ubuntu 16.04 or higher?”. Note that the suggestion to use PPA openjdk-r is outdated (the PPA has never updated their offering of openjdk-7-jdk, so it lacks security fixes); skip that answer even if it is the most upvoted.

Python

For building LineageOS 17.1 and above, you will need python3 as your system`s default. You can check this by calling python --version.

If you are building any of the older branches, python2 is required instead.
There are various methods to using it, e.g. symlinking it manually or creating a virtualenv for it.
We recommend the latter:

Generate the virtualenv once using virtualenv --python=python2 ~/.lineage_venv. Afterwards, activate it in each terminal where you need python2 as default by running ~/.lineage_venv/bin/activate.

The path ~/.lineage_venv can be chosen freely, this is just an example!

Create the directories

You’ll need to set up some directories in your build environment.

To create them:

mkdir -p ~/bin
mkdir -p ~/android/lineage

The ~/bin directory will contain the git-repo tool (commonly named “repo”) and the ~/android/lineage directory will contain the source code of LineageOS.

Install the repo command

Enter the following to download the repo binary and make it executable (runnable):

curl https://storage.googleapis.com/git-repo-downloads/repo > ~/bin/repo
chmod a+x ~/bin/repo

Put the ~/bin directory in your path of execution

In recent versions of Ubuntu, ~/bin should already be in your PATH. You can check this by opening ~/.profile with a text editor and verifying the following code exists (add it if it is missing):

# set PATH so it includes user's private bin if it exists
if [ -d "$HOME/bin" ] ; then
    PATH="$HOME/bin:$PATH"
fi

Then, run source ~/.profile to update your environment.

Configure git

Given that repo requires you to identify yourself to sync Android, run the following commands to configure your git identity:

git config --global user.email "[email protected]"
git config --global user.name "Your Name"

Turn on caching to speed up build

Make use of ccache if you want to speed up subsequent builds by running:

export USE_CCACHE=1
export CCACHE_EXEC=/usr/bin/ccache

and adding that line to your ~/.bashrc file. Then, specify the maximum amount of disk space you want ccache to use by typing this:

ccache -M 50G

where 50G corresponds to 50GB of cache. This needs to be run once. Anywhere from 25GB-100GB will result in very noticeably increased build speeds
(for instance, a typical 1hr build time can be reduced to 20min). If you’re only building for one device, 25GB-50GB is fine. If you plan to build
for several devices that do not share the same kernel source, aim for 75GB-100GB. This space will be permanently occupied on your drive, so take this
into consideration.

You can also enable the optional ccache compression. While this may involve a slight performance slowdown, it increases the number of files that fit in the cache. To enable it, run:

ccache -o compression=true

Initialize the LineageOS source repository

The following branches are officially supported for the Xiaomi Mi 8 Explorer Edition:

  • lineage-19.1

Enter the following to initialize the repository:

cd ~/android/lineage
repo init -u https://github.com/LineageOS/android.git -b lineage-19.1

Download the source code

To start the download of the source code to your computer, type the following:

repo sync

The LineageOS manifests include a sensible default configuration for repo, which we strongly suggest you use (i.e. don’t add any options to sync).
For reference, our default values are -j 4 and -c. The -j 4 part implies be four simultaneous threads/connections. If you experience
problems syncing, you can lower this to -j 3 or -j 2. On the other hand, -c makes repo to pull in only the current branch instead of all branches that are available on GitHub.

Prepare the device-specific code

After the source downloads, ensure you’re in the root of the source code (cd ~/android/lineage), then type:

source build/envsetup.sh
breakfast ursa

This will download your device’s device specific configuration and
kernel.

Extract proprietary blobs

Now ensure your Xiaomi Mi 8 Explorer Edition is connected to your computer via the USB cable, with ADB and root enabled, and that you are in the
~/android/lineage/device/xiaomi/ursa folder. Then run the extract-files.sh script:

./extract-files.sh

The blobs should be pulled into the ~/android/lineage/vendor/xiaomi folder. If you see “command not found” errors, adb may
need to be placed in ~/bin.

Start the build

Time to start building! Now, type:

croot
brunch ursa

The build should begin.

Install the build

Assuming the build completed without errors (it will be obvious when it finishes), type the following in the terminal window the build ran in:

cd $OUT

There you’ll find all the files that were created. The two files of more interest are:

  1. recovery.img, which is the LineageOS recovery image.

  2. lineage-19.1-20221007-UNOFFICIAL-ursa.zip, which is the LineageOS
    installer package.

Success! So… what’s next?

You’ve done it! Welcome to the elite club of self-builders. You’ve built your operating system from scratch, from the ground up. You are the master/mistress of your domain… and
hopefully you’ve learned a bit on the way and had some fun too.

Content of this page is based on informations from github and LineageOS Wiki, under CC BY-SA 3.0 licence.