BFE Engineering
e3a6026ba5
Drop the Why / What Works sections and the product-origin story; the text before Quick Start is now one comparison table of the upgrades over the vendor SDK. Coverage methodology stays in the internal docs as the reliability standard rather than the project's identity.
5.2 KiB
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).