GitHub – tech4bot/rk3562deb · GitHub

Current public build (pre-release, May 14, 2026):

Run full Debian 12 Bookworm on your Doogee U10 tablet — no bootloader unlock required.
Boot from SD card, remove it to return to stock Android. No changes to internal storage.

Reverse engineered from scratch — no BSP, no vendor documentation, no official support.
Built with the help of Claude, Codex, and Antigravity (Google Gemini), using Firefly RK3562 open-source repositories as a starting point.

rkdebian is a build system that produces a complete, bootable Debian 12 Bookworm image for the Doogee U10 Android tablet, powered by the Rockchip RK3562 SoC.

The resulting image is written to an SD card. Insert it and power on — the tablet boots Debian. Remove the SD card and it boots Android from internal eMMC as normal.

This tablet image supports local LLM inference on the RK3562 NPU using Rockchip’s RKLLM stack.

• Target platform: rk3562
• Quantization: W8A8
• NPU cores: num_npu_core=1 (RK3562 supports one NPU core)
• Optimization level: 0 (chosen for compatibility/stability on this board)

Example conversion command (host PC):

python3 convert_qwen_rk3562.py \
  --model-dir ./models/Qwen3-0.6B \
  --target-platform rk3562 \
  --quantized-dtype W8A8 \
  --optimization-level 0 \
  --num-npu-core 1 \
  --output ./out/Qwen3-0.6B_W8A8_RK3562_opt0.rkllm

Measured on April 6, 2026 on with:

• prompt: Output exactly 300 English words about arithmetic speed testing do not include punctuation and do not stop early
• MAX_NEW_TOKENS=64, MAX_CONTEXT_LEN=1024
• runner: ~/npu-test/xcompile/demo_Linux_aarch64/run_llm_rk3562.sh

Commands used:

# Qwen3-0.6B (first run includes fix_freq)
USE_FIX_FREQ=1 RKLLM_LOG_LEVEL=1 PROMPT="Output exactly 300 English words about arithmetic speed testing do not include punctuation and do not stop early" \
  ./run_llm_rk3562.sh ~/npu-test/models/Qwen3-0.6B_W8A8_RK3562_opt0.rkllm 64 1024

# Qwen2.5-1.5B
USE_FIX_FREQ=0 RKLLM_LOG_LEVEL=1 PROMPT="Output exactly 300 English words about arithmetic speed testing do not include punctuation and do not stop early" \
  ./run_llm_rk3562.sh ~/npu-test/models/Qwen2.5-1.5B-Instruct_W8A8_RK3562.rkllm 64 1024

Warm-run average (runs 2-3):

Result: Qwen3-0.6B is significantly faster on this RK3562 tablet for local NPU inference.

• Battery may report 0% after the tablet has been powered off for a couple of hours.
• rk-battery-gauge-fix.service fixes this on boot.
• If the tablet did not fully power off, reboot once; on the next boot the battery level should be corrected.
• Front (s5k5e8) and rear (s5k4h5yb) camera preview/capture are functional, but colors are still slightly off and require additional ISP calibration.

Host machine: x86-64 Linux (Debian/Ubuntu recommended)

Install all build dependencies with:

sudo apt-get install \
  git make gcc-aarch64-linux-gnu \
  bc bison flex device-tree-compiler \
  genimage wget tar mtools \
  xz-utils \
  debootstrap qemu-user-static \
  e2fsprogs

Builds U-Boot, kernel, Debian rootfs, and produces a ready-to-flash SD card image:

With full logging to file (tee) while preserving the real build exit status:

set -o pipefail
./build.sh all 2>&1 | tee build.log

./build.sh with no target defaults to all.

The final image is written to:

• out/rk3562-debian.img.xz — compressed final image (recommended)
• output/update/update.img.xz — compressed Firefly-compatible path

Compatibility/raw images are also kept:

• out/rk3562-debian.img
• output/update/update.img

./build.sh [options] lunch

image and updatepkg require existing build artifacts (out/rootfs, kernel/DTB, and boot config files).

These variables can be set before running build.sh to control build behaviour:

# Force a clean rootfs rebuild
RKDEBIAN_FORCE_CLEAN_ROOTFS=1 ./build.sh all

# Same using CLI flags
./build.sh all --force-clean-rootfs

# Force clean rootfs rebuild with a fixed 4 GB rootfs partition
RKDEBIAN_FORCE_CLEAN_ROOTFS=1 ROOTFS_IMAGE_SIZE=4G ./build.sh all

# Build only the rootfs, force clean
RKDEBIAN_FORCE_CLEAN_ROOTFS=1 ./build.sh rootfs

# Rebuild image only (U-Boot and kernel already built)
./build.sh image

# Build kernel only
./build.sh extboot

# Keep overlay PMIC patches during kernel build
RKDEBIAN_KEEP_OVERLAY_PMIC_PATCHES=1 ./build.sh extboot

# Force a Wayland desktop image for testing
./build.sh all --display-server=wayland

# Explicitly disable force-clean (useful in scripted runs)
./build.sh all --no-force-clean-rootfs

# Override baseline governor used for Phosh balanced mode mapping
RKDEBIAN_CPU_GOVERNOR=schedutil ./build.sh all

# Show CLI usage and target list
./build.sh --help

# Build a Phosh image on Mesa/Panfrost (clean rootfs strongly advised)
./build.sh all --ui-session=phosh --gpu-stack=panfrost --force-clean-rootfs

# Mali stack with Debian libgbm override (only for compatibility testing)
RKDEBIAN_MALI_GBM_PROVIDER=debian ./build.sh all --ui-session=phosh --gpu-stack=mali --force-clean-rootfs

# Size-focused build for easier GitHub uploads
RKDEBIAN_FORCE_CLEAN_ROOTFS=1 RKDEBIAN_MINIMIZE_IMAGE=1 RKDEBIAN_PREINSTALL_FREETUBE=0 ./build.sh all

# Size-focused build while keeping default FreeTube preinstall enabled
RKDEBIAN_FORCE_CLEAN_ROOTFS=1 RKDEBIAN_MINIMIZE_IMAGE=1 RKDEBIAN_PREINSTALL_FREETUBE=1 ./build.sh all

When changing RKDEBIAN_UI_SESSION or RKDEBIAN_GPU_STACK, use --force-clean-rootfs to avoid stale package carry-over.

Images include rk-power-profile-sync.service, which maps Phosh power modes
(power-profiles-daemon) to cpufreq policy on-device:

• balanced -> governor from RKDEBIAN_CPU_GOVERNOR (default performance), max freq cap 100%
• power-saver -> governor powersave, max freq cap 65%
• performance (if exposed by hardware) -> governor performance, max freq cap 100%

Tune mapping on-device in /etc/default/rk-power-profile-map.

• Rear camera flashlight is exposed as LED camera:flash, so Phosh shows the native top-menu torch icon.
• rk-flashlightctl supports both toggle and intensity control (set 0..100) for the rear LED.
• rk-powerkey-longpress.service owns hardware power-key policy:
  • short press (<3s) -> suspend on key release
  • long press (>=3s) -> standard GNOME shutdown dialog
  • logind/GNOME press-triggered defaults are disabled to avoid immediate sleep on key-down
• Lockscreen orientation is preserved from the last active tablet orientation, so wake/lock does not force portrait when the tablet was in landscape.

Images include rk-session-failsafe.timer, which checks 5 minutes after boot if a risky session test is still armed.

# Arm rollback before rebooting into a risky session test
sudo install -d /var/lib/rk-session-failsafe
sudo touch /var/lib/rk-session-failsafe/armed
sudo reboot

Behavior:

• If Phosh is healthy, watchdog auto-disarms and does nothing.
• If session bring-up fails, watchdog restores LightDM + Phosh autologin and reboots.

Once the tablet is running Debian, you can apply updates without reflashing the SD card.

Build an update package on your host:

./build.sh all        # or just ./build.sh image && ./build.sh updatepkg

This produces output/update/update.tar.gz.

Copy it to the tablet (via USB, SSH, or any file manager) and drop it in one of these inbox directories:

On the next reboot, the rk-apply-update service automatically detects the newest *.tar.gz or *.tgz package, applies rootfs + boot payloads, then reboots to finalize. Legacy compatibility path /update/update.tar.gz is also checked.

Package archive behavior:

• Successfully applied packages are moved to /update/applied/
• Invalid/extract-failed packages are moved to /update/failed/
• Already-applied packages (same SHA-256) are moved to /update/duplicate/

Update progress and errors are logged to /var/log/rk-update.log.

If a package fails to apply (corrupt archive, wrong layout) it is moved to /update/failed/ and the system boots normally.

After a successful build, flash the compressed image to your SD card:

# Replace /dev/sdX with your SD card device (check with lsblk)
xz -dc out/rk3562-debian.img.xz | sudo dd of=/dev/sdX bs=4M status=progress conv=fsync

Warning: Double-check the device path. Writing to the wrong device will overwrite your data.

Insert the SD card into the Doogee U10 and power it on. Debian will boot automatically.
Remove the SD card to return to Android.

The build system creates the following accounts in the Debian image:

Change these on first boot:

passwd                   # change chaos password
sudo passwd root         # change root password

The SD card image uses a GPT partition table:

The rootfs partition is automatically expanded to fill the SD card on first boot.

rkdebian/
├── build.sh              # Main build entry point
├── build_rootfs.sh       # Debian rootfs builder (debootstrap + chroot)
├── genimage.cfg          # SD card image partition layout
├── extlinux.conf         # Bootloader config (kernel + DTB)
├── splash.png            # Boot splash screen
├── overlay/              # Custom kernel drivers, DTS, firmware, services, and headers
│   ├── arch/             # Device tree sources (DTS/DTSI)
│   ├── drivers/          # Out-of-tree kernel drivers (Wi-Fi EA6621Q, cameras, PMIC)
│   ├── firmware/         # Wi-Fi firmware blobs (Seekwave EA6621Q)
│   ├── include/          # Build-time kernel header overrides
│   ├── kernel-patches/   # Kernel patches applied during build
│   ├── etc/              # On-device config overrides (logind, etc.)
│   ├── mali-shim.c       # Mali GPU userspace shim (compiled during build)
│   └── *.sh / *.service  # On-device setup scripts and systemd units
├── debs/                 # Pre-built .deb packages (Mali GPU, Rockchip MPP)
├── mali/                 # Mali GPU userspace library (.so)
├── wifi/                 # Wi-Fi firmware, vendor SDK, and porting guides
├── tools/                # On-device camera capture and ISP diagnostic tools
├── docs/                 # Design specs and build notes
├── src/                  # Cloned sources (kernel, u-boot, rkbin) — populated by build
├── out/                  # Build artifacts (kernel, rootfs, images)
└── output/update/        # Final flashable image + OTA update package

Third-party components included in this repository:

The prebuilt Mali GPU packages in debs/ and the userspace library in mali/ are sourced from:

These binaries are provided by those projects under their respective terms. ARM Mali firmware and userspace libraries are proprietary ARM IP.

The Rockchip MPP packages in debs/ (librockchip-mpp1, librockchip-mpp-dev, librockchip-vpu0) are sourced from:

Rockchip MPP is licensed under the Apache 2.0 License.

The Wi-Fi and Bluetooth driver source in overlay/drivers/net/wireless/ea6621q/ and firmware blobs in overlay/firmware/ and wifi/ are provided by Seekwave Technology Co. Ltd. The driver is released by the vendor under the GNU General Public License v2.0 (GPL-2.0).

MIT License — © 2026 tech4bot

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the “Software”), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

The Linux kernel, U-Boot, Debian packages, Rockchip rkbin, and third-party drivers included in or produced by this build system retain their respective upstream licenses.