TWRP device tree for Unihertz Jelly Max

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The Unihertz Jelly Max is a unique smartphone from Unihertz.

It was released in September 2024.

Device specifications

Basic	Spec Sheet
CPU	Octa-core CPU with 4x Arm Cortex-A78 up to 2.5 GHz
Chipset	Mediatek Dimensity 7300 (mt6878)
GPU	Mali-G615
Memory	12 GB RAM (LPDDR5T 9600Mbps)
Android	14
Storage	256 GB (UFS 3.1)
Display	720 x 1520 pixels, 5.05 inches, 60 hz
Battery	Lithium 4000 mAh, non-removable
Dimensions	128.7 x 62.7 x 16.3 mm
Weight	180g
Aux Slot	Second SIM or SDCard

Features

Works:

• ADB
• Decryption
• Display
• Fasbootd
• Flashing
• MTP
• Sideload
• USB OTG
• Vibrator

Preparation

Choose one of the recovery system:

Checkout minimal TWRP with AOSP tree:

mkdir ~/TWRP
cd ~/TWRP
curl https://raw.githubusercontent.com/GerritCodeReview/git-repo/refs/heads/main/repo > repo
chmod a+rx repo
./repo init --depth=1 -u https://github.com/minimal-manifest-twrp/platform_manifest_twrp_aosp.git -b twrp-14 -g default,-mips,-darwin,-notdefault
./repo sync -c --no-clone-bundle --no-tags --optimized-fetch --prune --force-sync -j4

Checkout minimal PBRP (PitchBlack):

mkdir ~/TWRP
cd ~/TWRP
curl https://raw.githubusercontent.com/GerritCodeReview/git-repo/refs/heads/main/repo > repo
chmod a+rx repo
./repo init --depth=1 -u https://github.com/PitchBlackRecoveryProject/manifest_pb.git -b android-14.0 -g default,-mips,-darwin,-notdefault
./repo sync -c --no-clone-bundle --no-tags --optimized-fetch --prune --force-sync -j4

Checkout minimal OFRP (OrangeFox):

mkdir ~/TWRP
mkdir ~/OrangeFox_sync
cd ~/OrangeFox_sync
git clone https://gitlab.com/OrangeFox/sync.git
cd ~/OrangeFox_sync/sync/
./orangefox_sync.sh --branch 12.1 --path ~/TWRP

Patch manifest.xml

mkdir ~/TWRP
sed -i '/\/asuite\"/d' ~/TWRP/.repo/manifests/remove-minimal.xml
./repo sync

Add device tree

git clone https://github.com/unihertz-jelly-max/twrp_device_unihertz_jmax.git ~/TWRP/device/unihertz

Build recovery image (vendor_boot.img)

export ALLOW_MISSING_DEPENDENCIES=true
export LC_ALL="C"
unset TOP ; unset OUT ; unset ${!TARGET_*} ; unset ${!BOARD_*} ; unset ${!PRODUCT_*} ; unset ${!OUT_*} ; unset ${!HOST_*} ; unset ${!KERNEL_*} ; unset ${!SOONG_*} ; unset ${!CLANG_*} ; unset ${!CROSS_*} ; unset ${!TWRP_*} ; unset ${!TW_*} ; unset ${!PB_*} ; unset ${!OF_*} ; unset ${!FOX_*}
unset NOT_ORANGEFOX

cd ~/TWRP
source build/envsetup.sh && lunch

Console output:

You're building on Linux

Lunch menu .. Here are the common combinations:
     1. aosp_arm-eng
     2. aosp_arm64-eng
     3. aosp_x86-eng
     4. aosp_x86_64-eng
     5. twrp_duchamp-eng
     6. twrp_jmax_A14_241029_eea-eng
     7. twrp_jmax_A14_241029_tee-eng
     8. twrp_jmax_A14_XXXXXX_eea-eng
     9. twrp_jmax_A14_XXXXXX_tee-eng

Which would you like? [aosp_arm-eng]
Pick from common choices above (e.g. 13) or specify your own (e.g. aosp_barbet-eng):

Enter the number of required device/firmware and type next command:

mka adbd vendorbootimage

To use it:

adb reboot bootloader
fastboot flash vendor_boot vendor_boot.img
fastboot reboot recovery