Xiaomi Redmi 9

Xiaomi Redmi 9 (lancelot/galahad)

Requirements

1. PC with ADB and fastboot drivers installed.
2. Unlock bootloader with Mi Unlock or using MTK Client.
3. Flash the latest MIUI firmware: mirror 1, mirror 2, mirror 3, mirror 4, mirror 5.
4. vbmeta.img, can be obtained from the extracted MIUI firmware, it can be found in the images folder.

Download GSIs

1. Download from Generic System Image (GSI) list .
2. Extract .xz to .img

Install a GSI

1. Boot into fastboot mode.

adb reboot bootloader

Or via key combination: hold Volume Down + Power while the device is turned off.

2. Disable verified boot.

fastboot --disable-verity --disable-verification flash vbmeta vbmeta.img

3. Moving fastboot from bootloader to userspace (fastbootd)

fastboot reboot fastboot

4. Flash the GSI.

fastboot flash system system.img

Note: system.img is the extracted GSI e.g system-td-arm64-ab-vanilla.img.

5. Wipe data from MIUI recovery.

fastboot reboot recovery

Choose Wipe Data → Wipe All Data → Confirm

6. Reboot.

Return to the main menu Recovery → Reboot → Reboot to System

Update a GSI

1. Enter fastboot in userspace (fastbootd).

adb reboot fastboot

2. Flash the GSI.

fastboot flash system system.img

Note: system.img is the extracted GSI e.g system-td-arm64-ab-vanilla.img.

3. Reboot

fastboot reboot

Note: No need to wipe data as long as the image is the same e.g AOSP to AOSP or LineageOS TD-based to LineageOS TD-based NOT AOSP to LineageOS TD-based or vice versa.

Hardware support

Component	Comment
Audio	Working
Display	Working
Backlight	Working → Enable Force alternative backlight scale to fix brightness slider
Camera	Working → Auxiliary cameras doesn't work
Bluetooth	Working → Choose Bluetooth workarounds → Mediatek
Telephony	Working
Fingerprint	Working
VoLTE	Working → Enable IMS features

Additional information

• Q: Do you have to enable Rotation perf hint instead of touch, Mediatek GED KPI support and/or Disable SF GL backpressure ?
• A: No

I've done 3DMark & Geekbench 6 benchmarks, here are the results:

3DMark (Vulkan)

Preferences	Enabled	Scores
Rotation perf hint instead of touch	Yes	671
Mediatek GED KPI support	Yes	672
Disable SF GL backpressure	Yes	668
The 3 options above	No	674

Geekbench CPU

Preferences	Enabled	Single-Core Scores	Multi-Core Scores
Rotation perf hint instead of touch	Yes	415	1365
Mediatek GED KPI support	Yes	416	1363
Disable SF GL backpressure	Yes	414	1374
The 3 options above	No	414	1379

Geekbench GPU (OpenCL)

Preferences	Enabled	Scores
Rotation perf hint instead of touch	Yes	1110
Mediatek GED KPI support	Yes	1112
Disable SF GL backpressure	Yes	1109
The 3 options above	No	1116

Geekbench GPU (Vulkan)

Preferences	Enabled	Scores
Rotation perf hint instead of touch	Yes	1080
Mediatek GED KPI support	Yes	1084
Disable SF GL backpressure	Yes	1076
The 3 options above	No	1090

Note: Reboot is performed before benchmarking in each session

Credits

• TrebleDroid developer team for all their hard work.
• All contributors for their respective contributions.