Android device tree for Xiaomi 14T (degas)

TWRP device tree targeting Android 14/16 (vendor_boot ramdisk, Virtual A/B)

Device Specifications

Feature	Specification
Codename	degas
Model	Xiaomi 14T (2406APNFAG)
SoC	MediaTek Dimensity 8300-Ultra (MT6897)
RAM	12 GB LPDDR5
Storage	256 / 512 GB UFS 4.0
Display	6.67" AMOLED, 2712 × 1220, 144 Hz
Battery	5000 mAh, 67W wired
Android	Ships with Android 14 (HyperOS)
TEE	MiTEE (MediaTek Trusted Execution Environment)
Encryption	f2fs aes-256-xts:aes-256-cts:v2+inlinecrypt

Tree Structure

android_device_xiaomi_degas/
├── BoardConfig.mk                  # Board-level build config (MT6897)
├── device.mk                       # Product packages, A/B OTA config
├── twrp_degas.mk                   # Top-level product makefile
├── Android.mk / AndroidProducts.mk # Build system hooks
├── system.prop                     # Default system properties
├── board-info.txt                  # Board verification
│
├── init/
│   ├── Android.bp                  # libinit_degas static library
│   └── init_degas.cpp              # Vendor init: brand/model/marketname overrides
│
├── bootctrl/                       # MTK Boot Control HAL v1.2
│   ├── Android.bp
│   ├── BootControl.cpp / .h
│   ├── boot_control_definition.h
│   ├── boot_region_control.cpp / _private.h
│   ├── ufs-mtk-ioctl.h
│   └── ufs-mtk-ioctl-private.h
│
├── mtk_plpath_utils/               # Preloader DM-device path utility
│   ├── Android.bp
│   └── mtk_plpath_utils.cpp
│
├── prebuilt/
│   └── dtb                         # Device Tree Blob extracted from vendor_boot
│
├── security/
│   └── miui_releasekey             # MIUI OTA release key (X.509 PEM)
│
└── recovery/root/
    ├── init.recovery.mt6897.rc     # TEE/MiTEE init, persist mount, TEE perms
    ├── init.recovery.usb.rc        # USB gadget (ADB/MTP/RNDIS)
    ├── first_stage_ramdisk/
    │   ├── fstab.mt6897            # First-stage fstab for MT6897
    │   └── fstab.emmc              # Alias (same content, UFS device)
    ├── system/etc/
    │   ├── recovery.fstab          # TWRP partition mount table
    │   └── persist.fstab           # /mnt/vendor/persist mount
    ├── lib/modules/
    │   ├── *.ko                    # 241 kernel modules from vendor_dlkm
    │   ├── modules.load            # Full vendor_dlkm load order
    │   ├── modules.load.recovery   # Recovery-only subset (TEE, USB, display, haptics)
    │   ├── modules.dep
    │   ├── modules.alias
    │   └── modules.softdep
    └── vendor/
        ├── bin/tee-supplicant
        ├── bin/hw/
        │   ├── android.hardware.gatekeeper-service.mitee
        │   ├── android.hardware.security.keymint@3.0-service.mitee
        │   └── vendor.xiaomi.hardware.vibratorfeature.service  # from /odm
        ├── lib64/                  # 9 vendor shared libraries (TEE, sensors, vibrator)
        ├── mitee/ta/               # 15 MiTEE Trusted Applications
        ├── firmware/               # 82 firmware blobs (haptics, touch, BT/WiFi, ISP)
        └── etc/
            ├── init/               # 5 RC files (TEE services, vibrator)
            ├── vintf/              # compatibility_matrix.xml, manifest.xml
            └── ueventd.rc

Building TWRP

Prerequisites

• TWRP 3.7+ build environment (AOSP twrp-14.1 manifest)
• Android build tools (Python 3, Ninja, ccache recommended)
• 16+ GB RAM, 250+ GB free disk space

Sync

Add to your local manifest (.repo/local_manifests/roomservice.xml):

<?xml version="1.0" encoding="UTF-8"?>
<manifest>
  <project name="android_device_xiaomi_degas"
           path="device/xiaomi/degas"
           remote="github"
           revision="twrp-14.1" />
</manifest>

Then:

repo sync device/xiaomi/degas

Build

. build/envsetup.sh
lunch twrp_degas-eng
mka vendorbootimage

The output vendor_boot.img will be in out/target/product/degas/.

Flash

# Boot into fastboot mode (Vol-Down + Power)
fastboot flash vendor_boot out/target/product/degas/vendor_boot.img
fastboot reboot

Note: This tree uses BOARD_USES_RECOVERY_AS_BOOT := false and installs TWRP into the vendor_boot ramdisk slot, consistent with the MTK VAB layout on degas.

Key Technical Notes

Partition Layout

• Virtual A/B (VAB) with 54 AB_OTA_PARTITIONS
• Dynamic super partition (sda20 on UFS, sda bus at 112b0000.ufshci)
• Boot LU A/B switching via UFS ioctl on /dev/block/sdc

Encryption

• Metadata: /dev/block/by-name/metadata → /metadata (f2fs)
• Userdata: fileencryption=aes-256-xts:aes-256-cts:v2+inlinecrypt_optimized
• Key directory: /metadata/vold/metadata_encryption
• Key mint HAL: android.hardware.security.keymint@3.0-service.mitee

TEE (MiTEE)

• 15 Trusted Applications in vendor/mitee/ta/
• tee-supplicant bridges in-kernel OP-TEE with user-space
• mitee.ko loaded from vendor_dlkm
• gz_trusty_mod.ko et al. required for GZ (Hypervisor) TEE side

Haptics

• AW8697 (aw8697_haptic.bin) — driven by haptic.ko
• SI Haptic — driven by si_haptic.ko
• Vibrator HAL: vendor.xiaomi.hardware.vibratorfeature.service (from /odm/bin/hw/ on device)

Reference Tree

Structural reference: JonesqPacMan/android_device_xiaomi_rothko_twrp (branch twrp-14.1_a16) Note: rothko is MT6989 (Dimensity 9300); degas is MT6897 (Dimensity 8300-Ultra) — different SoC family.

Credits

• JonesqPacMan – rothko tree (structural reference)
• TeamWin – TWRP
• LineageOS – MTK boot control HAL base