bfe-core1106-sdk

A modern, open development environment for the Luckfox Pico 86 Panel (Rockchip RV1106), replacing the vendor SDK — and honest about what runs on real silicon versus what is simulated.

	Vendor SDK	This repo
Kernel	5.10.160, twice-forked, frozen	6.18.46 — a reviewable, subsystem-split patch series onto pristine upstream; full peripheral set (display, touch, wifi, audio, NPU, ...) hardware-verified on a bench panel
Build	~2 GB tree, absolute paths baked in, Kconfig options silently dropped	one hermetic script: sha256-pinned source fetch, fail-closed patch apply and config fragments
Off-device testing	none — every change means flashing a panel	register-level hardware models (sim/) plus a QEMU device VM booting the real kernel, real daemons, and the real UI with display + touch
Config safety	memory-map mistakes reach hardware (one bricked a bench unit)	static gates (tools/config-lint) catch them before any flash
CI	none	hosted pipeline: tests, coverage, benchmarks, patch-apply gate, kernel build with an in-CI QEMU boot smoke
Flashing tools	closed (upgrade_tool)	open (rkdeveloptool)
License	mixed	GPL-2.0-only, with a per-driver provenance ledger

Quick Start

Requirements: gcc-arm-linux-gnueabihf, qemu-system-arm, curl, cpio, mkfs.ext4, a bare python on PATH (Debian/Ubuntu: python-is-python3), gcc >= 14 (driver harnesses), and Rust (for the simulators' tests).

# 1. Build the kernel: fetch pinned pristine 6.18.46, apply patches/, emit
#    zImage + rv1106-warden.dtb. WORK must sit outside any git checkout.
WORK=$HOME/kbuild-out CROSS_COMPILE=arm-linux-gnueabihf- bash build/build-kernel.sh

# 2. Boot it in the QEMU device simulator (no hardware needed):
bash qemu/mkinitramfs.sh
bash qemu/mkimage.sh
bash qemu/run.sh --kernel $HOME/kbuild-out/linux-6.18.46/arch/arm/boot/zImage --shell

# 3. Run the test suites:
for d in sim tools/config-lint qemu/rs485-bridge; do
  (cd "$d" && cargo test)
done
for d in drivers/*/test; do make -C "$d" check; done  # driver harnesses (gcc >= 14)

Add WARDEN_KCONFIG_FRAGMENT=qemu/configs/virt.fragment to step 1 for the kernel variant with the simulator's extra devices; qemu/README.md has the scenario tests (portal, OTA apply, display + touch, watchdog).

Layout

Directory	Contents
patches/	the RV1106 forward-port onto pristine linux-6.18.46, subsystem-split
build/	hermetic kernel build: pinned fetch → apply patches → zImage + dtb
qemu/	device simulator: QEMU -M virt boots the real kernel and real userspace
sim/	register-level hardware models (Rust): membus, HPMCU, CRU, Modbus, RGA, NPU
drivers/	hardened hardware-facing drivers: HAL seams, test harnesses
kernel/	forward-port provenance and bring-up records (patches/ is canonical)
tools/	config-lint (static memory-map gates) and dev tooling
docs/	architecture, ADRs (decisions/), CI/CD

Architecture

One thin hardware abstraction seam per block (a trait in Rust, a function table in C): firmware logic talks to the seam; the seam binds a real backend on the device or a simulated backend on the host. The driver test harnesses measure against the same seam the simulator implements, so the two reinforce each other. Full detail: docs/architecture.md.

Simulator	Runs	Proves
sim/	register-level Rust models	driver and supervisor logic, with fault injection
qemu/	the real kernel + userspace on -M virt	boot, init, daemons, networking, OTA, watchdog, display + touch
lvglsim (downstream)	the LVGL UI on SDL	rendering and UI flows

With the production UI binary in qemu/payload/, run.sh --display on opens the panel's 720x720 screen in a window, mouse clicks landing as touch — device and UI in one VM. Emulation results are never on-silicon evidence; the simulators narrow which claims need a panel.

Principles

• Open — open tools over closed ones; GPL-2.0-only.
• Hard — every seam has a fault-injection path; recovery code is tested against failure, not just success.
• Modern — the newest kernel the hardware can run, current toolchains, Rust for new host-testable code, reproducible builds.

Downstream

A private firmware repo (flare-edge) consumes this SDK; issue references and checkout paths pointing there are engineering context, not reachable links. The QEMU simulator runs its production binaries unmodified — real over-the-air updates included.

License

GPL-2.0-only, repo-wide (LICENSE; a per-file SPDX identifier governs where present). patches/ and kernel/ are derivative of the Linux kernel and GPL-2.0 vendor code; per-driver origin is tracked in kernel/rv1106-enablement/PROVENANCE.md. Contributions are accepted under the same license (inbound = outbound).