[PATCH v4 0/3] Add Luckfox Omni3576 Carrier Board support for RK3576

[John Clark <inindev@gmail.com>]

This series adds device tree support for the Luckfox Omni3576 Carrier
Board with the Core3576 Module, powered by the Rockchip RK3576 SoC
(four Cortex-A72 cores, four Cortex-A53 cores, Mali-G52 MC3 GPU). It
enables essential functionality for booting Linux and basic connectivity,
with plans for future support of peripherals like WiFi, MIPI-DSI, HDMI,
and Ethernet.

Tested features (on Linux 6.15-rc4):
 - UART: Serial console operational
 - SD card: Mounts and reads/writes successfully
 - PCIe: NVMe SSD detected, mounted, and fully functional
 - USB 2.0: Host ports operational
 - RTC: Timekeeping and wake-up tested
 - LED: Heartbeat trigger functional
 - eMMC: Enabled in device tree, not populated on tested hardware

The series includes three patches:
 1. dt-bindings: vendor-prefixes: Add Luckfox vendor prefix
 2. dt-bindings: arm: rockchip: Add Luckfox Omni3576 and Core3576 bindings
 3. arm64: dts: rockchip: Add Luckfox Omni3576 board support

The device tree is covered by the existing ROCKCHIP ARCHITECTURE entry in
MAINTAINERS. I am aware of ongoing RK3576 upstreaming efforts (e.g., by
Collabora) and welcome feedback or collaboration to align with mainline
driver development.

Changes in v4:
 - Patch 1: Unchanged, Acked-by: Conor Dooley <conor.dooley@microchip.com>.
 - Patch 2: Fixed binding for Omni3576 Carrier Board to use correct enum
   syntax (enum: [luckfox,omni3576] instead of invalid const), added
   luckfox,core3576 to compatible string to reflect module dependency.
 - Patch 3: Updated compatible string in rk3576-luckfox-omni3576.dts to
   match revised binding ("luckfox,omni3576", "luckfox,core3576",
   "rockchip,rk3576").

Changes in v3:
 - Split device tree into rk3576-luckfox-core3576.dtsi (module) and
   rk3576-luckfox-omni3576.dts (carrier board) for better modularity.
   Previous Acked-by from Krzysztof Kozlowski for Patch 2 no longer applies
   due to substantial changes.
 - Addressed Jonas Karlman's feedback on patch 3/3 (Luckfox Omni3576
   device tree):
   - Added pinctrl for green LED GPIO (gpio1 RK_PD5) for proper pin setup.
   - Reordered regulator node properties for consistent sequence (e.g.,
     regulator-name, regulator-min-microvolt, regulator-max-microvolt,
     etc.).
   - Updated regulator nodes (vcc_3v3_pcie, vbus_5v0_typec, vcc_5v0_host,
     vcc_5v0_hdmi) to use 'gpios' property instead of deprecated 'gpio'.
   - Removed pmic-power-off pinctrl state and pinctrl-1 from RK806 PMIC
     node, as they are vendor-specific and undocumented in bindings.
   - Removed pwrkey node from PMIC, as it lacks binding documentation.
   - Added blank line between properties and child nodes in i2c2 node for
     DT style compliance.
   - Removed no-mmc property from sdmmc node to enable MMC support,
     aligning with RK3576 SD v3.0 and MMC v4.51 capabilities, allowing TF
     card slot to support MMC devices or eMMC via adapter.
 - Removed Ethernet support (gmac0/gmac1 nodes) per Andrew Lunn's
   feedback, as it used the generic PHY driver with incorrect RGMII delay
   settings, incompatible with the upcoming MAE0621A driver.
   Collaborating with Andrew Lunn on a device driver, with Ethernet
   support to be submitted separately when complete.
 - Addressed Rob Herring's DTB check warnings, other warnings (e.g., VOP,
   PCIe, OTP, HDMI PHY) originate from rk3576.dtsi and are outside this
   patchset scope.
 - Added RNG node to pick up Nicolas Frattaroli's "add RK3576 RNG node"
   patch.

Changes in v2:
 - Enabled HDMI node per feedback from Heiko Stuebner and Nicolas
   Frattaroli; untested due to upstream driver issues.
 - Enabled Ethernet 1 node per Heiko's device tree philosophy; untested
   due to suspected PHY driver or configuration issues (removed in v3 per
   Andrew Lunn).
 - Clarified eMMC remains enabled but unpopulated on tested board, per
   Heiko.

Signed-off-by: John Clark <inindev@gmail.com>
---
John Clark (3):
  dt-bindings: vendor-prefixes: Add luckfox prefix
  dt-bindings: arm: rockchip: Add Luckfox Omni3576 and Core3576 bindings
  arm64: dts: rockchip: Add Luckfox Omni3576 Board support

 .../devicetree/bindings/arm/rockchip.yaml     |   7 +
 .../devicetree/bindings/vendor-prefixes.yaml  |   2 +
 arch/arm64/boot/dts/rockchip/Makefile         |   1 +
 .../dts/rockchip/rk3576-luckfox-core3576.dtsi | 683 ++++++++++++++++++
 .../dts/rockchip/rk3576-luckfox-omni3576.dts  |  53 ++
 5 files changed, 746 insertions(+)
 create mode 100644 arch/arm64/boot/dts/rockchip/rk3576-luckfox-core3576.dtsi
 create mode 100644 arch/arm64/boot/dts/rockchip/rk3576-luckfox-omni3576.dts

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2.39.5