Linux 7.1 Mainline for Samsung Galaxy Tab A8 10.5 (SM-X200 / SM-X207)

Linux 7.1.0-rc1 mainline kernel bring-up for Samsung Galaxy Tab A8 10.5 (2021) based on the Unisoc Tiger T618 SoC (ums512_25c10 / sharkl5pro).

Current Milestone: Native Linux Desktop Booting
Boots native Ubuntu 24.04 LTS (Noble Numbat) arm64 on the internal eMMC (/dev/mmcblk3p56) directly into a full KDE Plasma Wayland session with hardware-accelerated 3D rendering (Panfrost Mali-G52 MC2), native 1200x1920 @ 60 Hz KMS display, and responsive 10-point multi-touch (Novatek NT36523B TDDI).

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Hardware Status

Subsystem	Component	Status	Details
Bootloader Handoff	Stock Samsung LK	✅ Working	Relocated 2 MiB stub (reloc.S), AVB 64 MiB hash footer, dtbo-noop.img
Display (KMS)	Unisoc DPU r4p0	✅ Working	Native atomic KMS driver (ums512_dpu_kms.c), adopts LK MIPI-DSI, native 1200x1920 @ 60 Hz
3D Acceleration	Mali-G52 MC2	✅ Working	panfrost (card1 / renderD128), paired with DPU KMS (card0) under Wayland / KWin
Touchscreen	Novatek NT36523B TDDI	✅ Working	SPI2 (0x70a00000, spi2.1), autoloads nt36523b_qc_inx_fw.bin, 10-point multi-touch
USB Peripheral	MUSB / CDC ACM	✅ Working	USB Gadget serial console on host /dev/ttyACM0 (/dev/ttyGS0 device)
Fuel Gauge / Battery	SC2730 FGU	⚠️ In Progress	DT node mapped (sprd,sc2730-fgu @ 0x4002e000), battery monitoring driver in progress
USB Host / OTG	MUSB Dual-Role	⚠️ In Progress	Controller mapped; Type-C VBUS role switching under test
Audio	SC2730 Codec + AW88266	❌ WIP	SIPC/AGDSP loads; machine sound card and codec DAI links pending
Wi-Fi / Bluetooth	Unisoc Marlin3-Lite (SC2355)	❌ WIP	WCN bus probes; SDIO DT nodes and cfg80211 driver (sprdwl_ng) port pending

See tools/gta8-bringup/BRINGUP-NOTES.md for detailed register maps, errata, timing fixes, and driver architecture.

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Repository Structure

• arch/arm64/boot/dts/sprd/ums512-samsung-gta8.dts: Target device tree (touchscreen, DPU, GPU, PMIC, memory reserves).
• arch/arm64/boot/dts/sprd/ums512.dtsi: SoC core dtsi (SPI2, DPU, HSIC/PHY, clocks, interrupts).
• arch/arm64/configs/gta8_defconfig: Dedicated defconfig (256 MiB CMA, DPU KMS, Panfrost, Novatek TS, no top-DVFS).
• drivers/gpu/drm/sprd/ums512_dpu_kms.c: Native DRM KMS driver for Unisoc DPU r4p0.
• drivers/input/touchscreen/novatek_nt36xxx/: Novatek NT36523B SPI touchscreen driver with Samsung-specific trimming.
• tools/gta8-bringup/:
  • build.sh: Orchestrates kernel build, initramfs packing, and image packaging.
  • mkbootimg-gta8.sh: Packages boot.img with LK-compliant header, DTB table, reloc stub, and AVB footer.
  • initramfs-init: Lightweight bring-up init script (auto-detects rootfs on eMMC /dev/mmcblk3p56, handles fallback shell).
  • BRINGUP-NOTES.md: Comprehensive bring-up documentation and hardware notes.

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Building and Flashing

1. Host Dependencies

Cross compiler (aarch64-linux-gnu-gcc), bc, cpio, gzip, python3, mkbootimg, mkdtboimg, avbtool (android-tools), adb.

2. Neutralise Stock DTBO (One-time step)

Stock Samsung LK merges overlays from the dtbo partition that reference vendor kernel 4.14 nodes and crash mainline. Flash the empty matching dtbo table once:

tools/gta8-bringup/build.sh --flash-dtbo

(Automatically backs up stock dtbo to dtbo-stock-backup.img before writing).

3. Build & Flash Kernel

With the tablet connected in recovery mode (adb root):

tools/gta8-bringup/build.sh --flash

This builds Image, compiles sprd/ums512-samsung-gta8.dtb, packages boot-gta8.img with AVB signature, and flashes /dev/block/by-name/boot.

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Userspace & Wayland Setup (KDE Plasma on Ubuntu 24.04)

The rootfs is placed on partition 56 of the internal eMMC (/dev/mmcblk3p56, or /dev/block/mmcblk0p56 in recovery).

Environment Configuration (/etc/environment)

To ensure KWin / Wayland correctly binds to the DPU KMS scanout while dispatching 3D rendering to Panfrost:

KWIN_DRM_DEVICES=/dev/dri/card0
KWIN_FORCE_SW_CURSOR=1
KWIN_DRM_USE_MODIFIERS=0
QT_QPA_PLATFORM=wayland;xcb

Touchscreen Firmware

Place Novatek firmware files in /lib/firmware/:

• nt36523b_qc_inx_fw.bin (symlinked as novatek_ts_fw.bin)
• nt36523b_qc_inx_mp.bin