bfe-core1106-sdk/kernel/rv1106-enablement/PORT-STATUS.md

RV1106 → 6.18 forward-port — live status

Target: Linux 6.18.46 (vanilla, flare-edge/research/linux-6.18.46/), forward-ported from the vendor 5.10.160 tree, no plan44 code, built with our arm-rockchip830-...-gcc 8.3 (confirmed: gcc 8.3 builds 6.18 fine).

Confirmed feasibility facts

• gcc 8.3 (our SDK toolchain) compiles the 6.18 kernel — no toolchain bump needed to start.
• multi_v7_defconfig (ARM + rockchip) configures; CLK_RV1106=y wires in cleanly.
• rv1106's siblings rv1126/rv1108 exist in both trees, so their 5.10→6.18 delta is a working template for the framework API changes.

M1 — clock driver (clk-rv1106.c, 1294 lines): ✅ COMPILES CLEAN on 6.18

Build-fix loop against 6.18 — clk-rv1106.o (85732 bytes) builds with no errors. Fixed (captured in clk/):

1. Kconfig + Makefile hooks — added CONFIG_CLK_RV1106 (mirrors CLK_RV1126).

2. CRU register macros — ported all 55 RV1106_* register-accessor #defines from the vendor clk.h into 6.18's clk.h (mainline has none).

3. Header split — panic_notifier_list moved to <linux/panic_notifier.h> (kernel 5.18); added the include.

4. rockchip_clk_register_armclk signature change — 5.10 took (num_parents, parent_clk, alt_parent_clk); 6.18 takes (parent_names[], num_parents) and drives the mux from reg_data.mux_core_main/alt. Adapted the call to the 6.18 form using a parent-names array (sibling-delta from rv1126). ⚠ PORT-VERIFY: the mux input list { "gpll","cpll","apll" } and the mux_core_main/alt=2 mapping are a best-effort from the 5.10 intent (main=apll) — they set the CPU clock source, so they must be checked against the RV1106 CORECLKSEL_CON register map (TRM) and validated on hardware before trusting a boot. A wrong mux silently breaks boot.

5. CLK_FRAC_DIVIDER_NO_LIMIT — Rockchip downstream-only frac-divider flag (6 uses on the UART frac clocks); mainline has no min/max opt-out, mapped to 0 (default limit). ⚠ PORT-VERIFY: UART fractional baud accuracy.

M1 — pinctrl (pinctrl-rockchip.c/.h): ✅ COMPILES CLEAN on 6.18

pinctrl-rockchip.o (173688 bytes) builds no-errors. Transplanted from vendor 5.10 (effort S, zero API drift — the survey's assessment held): added RV1106 to the type enum; a 159-line block of RV1106_DRV/PULL/SMT_* macros + 3 rv1106_calc_*_reg_and_bit() functions; case RV1106: in the 3 pull functions + the RK3568 drive-strength group; rv1106_pin_banks[] + rv1106_pin_ctrl; and the rockchip,rv1106-pinctrl of_device_id (dropping the vendor's #ifdef CONFIG_CPU_RV1106 guard — mainline compiles all SoCs unconditionally). Captured as pinctrl/0001-rv1106-pinctrl.patch.

• PORT-VERIFY RESOLVED (iomux offsets): the DRV/PULL/SMT per-bank offsets are confirmed by a THIRD independent source — the upstream Simon Glass v3 pinctrl patch. Its rv1106_{drv,pull,smt}_offsets[] match ours exactly once the 0x10000-strided per-bank IOC base is applied (e.g. vendor GPIO2 DRV 0x100C0 = 0x10000 + 0xc0). Retires the "do not guess" iomux risk without hardware. (Note upstream uses per-bank IOC regmaps + low offsets; we use the vendor's full-offset form — same absolute register, both compile.)
• Still PORT-VERIFY: GPIO4 bank pin-count (pin_banks says 24, DT gpio-ranges says 32) — carried from vendor unchanged; needs TRM/hardware.

M1 — mach: ✅ DONE

mach-rockchip RV1106/RV1103 SoC recognition added as a DT-compat entry (no CPU_RV1106 symbol recreated). Captured as mach/0001-rv1106-soc-recognition.patch. M1 is complete: clk + pinctrl + mach all compile clean on 6.18.

M2 — earlycon build: ✅ DONE (boot pending hardware)

The first full kernel build with our SoC drivers, 2026-08-24:

• multi_v7_defconfig + configs/m2-earlycon.fragment builds an 11.8 MB zImage with clk-rv1106.o (85732 B) and pinctrl-rockchip.o (173688 B, our rv1106 data) compiled into the full tree — no rv1106 warnings/errors. Reproducible via build-m2.sh.
• dts/rv1106-warden-m2.dts → rv1106-warden-m2.dtb compiles clean (W=1, no dtc warnings). A deliberately minimal DT — CPU (cortex-a7), GIC-400, arch timer, 256 MiB RAM, GRF, the CRU (our clk-rv1106), and uart2 (snps,dw-apb-uart, the console) — with earlycon=uart8250,mmio32,0xff4c0000 so the first print reuses the loader's divisor before any clock/pinctrl probe.

Still PORT-VERIFY before a boot is trusted: memory size/base (256 MiB @ 0x0 assumed — the loader usually patches this); the CPU clock mux in clk-rv1106 (§M1 item 4); the console baud (1.5M assumed). A wrong DDR/clock value silently hangs before or just after earlycon.

M2 — boot: NEXT (on hardware)

Package zImage + rv1106-warden-m2.dtb into a boot image and load on a bench unit (c8a3 / w7159, both with a proven recovery net), watching the debug UART — or the coprocessor USB console (R5) — for the earlycon "it's alive". A hang is expected to be one of the PORT-VERIFY values above; iterate with recovery ready. This is an attended step (brick-adjacent), not an unattended one.

Then M3: dw_mmc DT + rootfs on our Buildroot userspace.

Upstream tracking (decision 2026-08-23)

Base stays the vendor forward-port (applies to 6.18; we control it). The unmerged upstream RV1106 series (~35 patches, "New" state, does NOT apply cleanly to 6.18 — pinctrl v3 failed at pinctrl-rockchip.c:3390) is used as a correctness oracle for boot-critical PORT-VERIFY values (already retired the iomux offsets) and tracked for eventual convergence when it merges.

Honest scope

This is the first driver of ~120 in the RV1106 BSP. The clk port alone is a multi-cycle effort of the four delta classes above; the whole bring-up (M1–M6 in ../docs/bringup.md) is a multi-month kernel effort. Progress is real and the method is proven; correctness of boot-critical pieces (clock mux, PLL rates, DDR, pinctrl iomux) requires the TRM and on-hardware validation — which waits on c8a3's recovery and, ultimately, careful bring-up.

Layout

clk/        clk-rv1106.c + rv1106-cru.h + framework-hooks patch (M1)
pinctrl/    0001-rv1106-pinctrl.patch                              (M1)
mach/       0001-rv1106-soc-recognition.patch                     (M1)
dts/        rv1106-warden-m2.dts   minimal earlycon board DT       (M2)
configs/    m2-earlycon.fragment   defconfig delta over multi_v7   (M2)
build-m2.sh reproducible M2 build (zImage + dtb)

The full ported tree lives in flare-edge/research/linux-6.18.46/ (scratch); this dir is the durable, reviewable capture, to become a proper patch series as milestones land.