tech4bot/rk3562deb

Source: https://github.com/tech4bot/rk3562deb

rkdebian — Debian 12 for Doogee U10 (RK3562)

Download Pre-release Image

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

• Release page: tech4bot/rk3562deb prerelease-14052026
• Direct image download: rk3562-debian.img.xz
• Video demo: YouTube

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.

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Overview

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.

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Hardware: Doogee U10

Component	Details
SoC	Rockchip RK3562 (4× Cortex-A53 @ 2.0 GHz)
NPU	1× Rockchip NPU core (active for RKLLM inference)
RAM	4 GB LPDDR4
Storage	128 GB eMMC (Android) + SD card (Debian)
Display	10.1“ DSI panel, 1280×800
PMIC	RK817

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What Works

Feature	Status
Display / Panel	✅ Full
Touchscreen	✅ Full (gsl3673, 10-point multitouch)
Wi-Fi	✅ Full (Seekwave EA6621Q)
Bluetooth	✅ Full
Speaker / Audio output	✅ Full
Microphone	✅ Full
3D Acceleration	⚠️ Partial (Panfrost, OpenGL ES works)
NPU (RKLLM / rknn-llm)	✅ Active (RK3562 supports one NPU core, num_npu_core=1)
Accelerometer	✅ Full (SC7A20 / DA223)
Flashlight (rear LED)	✅ Full (native Phosh top-menu torch toggle + brightness control via rk-flashlightctl)
Power button behavior	✅ Full (short press sleeps on release, long press >=3s opens shutdown dialog)
Lockscreen orientation memory	✅ Full (lock screen keeps last tablet orientation, including landscape)
Cameras	⚠️ Partial (front s5k5e8 + rear s5k4h5yb pipelines functional; color tuning still needs calibration)
Battery / Charging	✅ Full (RK817 PMIC)
SD card boot	✅ Full
USB OTG	✅ Full

Default Installed Apps

App	Notes
Firefox ESR	Preinstalled web browser
Chromium	Preinstalled web browser (installed when available on mirror)
FreeTube	Installed via Flatpak from Flathub by default (disable with RKDEBIAN_PREINSTALL_FREETUBE=0 for smaller images)
Drawing	Touch-friendly paint app (installed when available on mirror)
Snapshot	Camera app (installed when available on mirror)
Dolphin	File manager
Plasma Discover	App store / software center
Okular	Document/PDF viewer
Gedit	Text editor
Pavucontrol	Audio controls
Terminal	kgx preferred, gnome-terminal fallback
Flatpak + Flathub	Enabled by default for app installs

NPU LLM (RK3562)

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

NPU software used

• airockchip/rknn-llm — runtime, RKLLM toolkit, demo app (llm_demo)
• airockchip/rknn-toolkit2 — RKNN conversion/toolchain dependency used by RKLLM workflows

Model conversion setup used

• 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

Benchmark (on tablet, NPU path)

Measured on April 6, 2026 on <tablet-ip> 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):

Model	Init Time (ms)	Prefill (tok/s)	Generate (tok/s)
Qwen3-0.6B_W8A8_RK3562_opt0	1788.70	57.62	4.92
Qwen2.5-1.5B-Instruct_W8A8_RK3562	4800.76	42.78	2.18

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

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Known Issues

• 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.

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Requirements

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

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Building

Full build (recommended)

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

./build.sh all

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

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CLI usage and options

./build.sh [options] {check|lunch|uboot|extboot|updateimg|updatepkg|compile|rootfs|image|all}

Option	Values	Description
--ui-session	phosh	Session profile to bake into the image
--gpu-stack	mali, panfrost	Select userspace/kernel graphics stack
--display-server	auto, wayland, x11	Desktop backend preference passed into rootfs build
--cpu-governor	e.g. performance, schedutil	Baseline governor used by power-tuning services
--force-clean-rootfs	flag	Force full rootfs rebuild (same effect as RKDEBIAN_FORCE_CLEAN_ROOTFS=1)
--no-force-clean-rootfs	flag	Explicitly disable forced rootfs cleanup
-h, --help	flag	Show usage

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Individual build targets

Command	What it does
./build.sh check	Verify all build dependencies are installed
./build.sh lunch	Select a build configuration (defconfig)
./build.sh uboot	Build U-Boot only
./build.sh extboot	Build the Linux kernel only
./build.sh rootfs	Build the Debian 12 rootfs only, then verify the requested build profile marker
./build.sh compile	Build U-Boot + kernel (skip rootfs and image)
./build.sh image	Assemble the final SD card image from existing artifacts (with rootfs profile verification)
./build.sh updateimg	Legacy image assembly path (SDK-compat); packages image without running profile verification
./build.sh updatepkg	Create an offline update tarball (output/update/update.tar.gz) from out/rootfs + out/boot/*
./build.sh all	Full end-to-end build (default)

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

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Environment Variables

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

Rootfs

Variable	Default	Description
RKDEBIAN_FORCE_CLEAN_ROOTFS	0	Set to 1 to wipe and fully rebuild the Debian rootfs from scratch. Useful when switching between different image profiles so stale packages do not carry over.
ROOTFS_IMAGE_SIZE	auto	Override the rootfs partition size (e.g. 4G, 3584M). By default the size is calculated automatically from actual rootfs usage plus headroom.
ROOTFS_HEADROOM_MB	512	Free space headroom added on top of actual rootfs usage when using auto sizing.
ROOTFS_MIN_MB	2560	Minimum rootfs image size in MiB when using auto sizing.
RKDEBIAN_DISPLAY_SERVER	wayland	Session backend preference for desktop stack selection (wayland, x11, or auto). Phosh images use Wayland by default.
RKDEBIAN_UI_SESSION	phosh	UI session to auto-login in LightDM. Current supported value: phosh.
RKDEBIAN_GPU_STACK	mali	GPU stack to build for: mali (vendor userspace) or panfrost (Mesa/Panfrost, no libmali).
RKDEBIAN_CPU_GOVERNOR	performance	Baseline CPU governor used at boot and as the default mapping for Phosh balanced mode.
RKDEBIAN_MALI_GBM_PROVIDER	vendor	Mali-only option: vendor keeps mali/libgbm.so.1 from the blob package (default), debian overrides it to Debian libgbm.so.1 for compatibility testing.
RKDEBIAN_PREINSTALL_FREETUBE	1	Set to 0 to skip FreeTube preinstall and significantly reduce image size.
RKDEBIAN_MINIMIZE_IMAGE	0	Set to 1 for aggressive size reduction (prunes non-English locales plus /usr/share/doc, /usr/share/help, /usr/share/man, /usr/share/info, and unused Flatpak objects).

Kernel

Variable	Default	Description
RKDEBIAN_MAKE_THREADS	auto	Override kernel build parallelism. By default it uses a memory-safe value (min(nproc, RAM_GiB/2)) to reduce random cc1/drivers build failures on low-RAM hosts.
RKDEBIAN_KEEP_OVERLAY_PMIC_PATCHES	0	Set to 1 to use the overlay PMIC drivers (rk808.c, rk817_battery.c, rk817_charger.c) instead of the upstream kernel versions.

Examples

# 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.

Phosh Power Mode Mapping

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.

Phosh UX Integrations

• 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.

Safe Phosh Session Testing (on-device)

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.

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OTA Updates (on-device)

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:

Path	Notes
/home/chaos/update/	Primary drop location
/update/pending/	Alternative drop location

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.

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Flashing to SD Card

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.

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Default Credentials

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

Account	Username	Password	Notes
Standard user	chaos	chaos	Passwordless sudo
Root	root	root	Direct root login

Change these on first boot:

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

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Image Layout

The SD card image uses a GPT partition table:

Partition	Offset	Size	Contents
idbloader	32 KiB	—	SPL / first-stage bootloader
uboot	8 MiB	—	U-Boot FIT image
boot	16 MiB	256 MiB	FAT: kernel Image, DTB, extlinux.conf
rootfs	272 MiB	auto	ext4: Debian 12 Bookworm root filesystem

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

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Source Tree

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

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Kernel & Bootloader Versions

Component	Version / Branch
Linux kernel	6.1.x (develop-6.1, rockchip-linux)
U-Boot	Firefly rk356x/firefly-5.10
rkbin	Rockchip upstream master
Debian	12 Bookworm (arm64)

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Attribution

Third-party components included in this repository:

Mali GPU binaries

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

• christianhaitian/rk3566_core_builds
• tsukumijima/libmali-rockchip

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

Rockchip MPP (Media Process Platform)

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

• rockchip-linux/mpp

Rockchip MPP is licensed under the Apache 2.0 License.

Seekwave Wi-Fi / Bluetooth

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).

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License

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.