arm64: dts: rockchip: Add devicetree for NanoPC-T4

This adds a device tree for the NanoPC-T4 SBC, which is based on the
Rockchip RK3399 SoC and marketed by FriendlyELEC.

Known working:

- Serial
- Ethernet
- HDMI
- USB 2.0

All of the interesting stuff is in a .dtsi because there are at least
two other boards that share most of it: NanoPi M4 and NanoPi NEO4.

Signed-off-by: Tomeu Vizoso <tomeu.vizoso@collabora.com>
Reviewed-by: Rob Herring <robh@kernel.org>
[rm: various further cleanup]
Signed-off-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

Documentation/devicetree/bindings/arm/rockchip.yaml

@@ -87,6 +87,11 @@ properties:
           - const: firefly,roc-rk3399-pc
           - const: rockchip,rk3399
 
+      - description: FriendlyElec NanoPC-T4
+        items:
+          - const: friendlyarm,nanopc-t4
+          - const: rockchip,rk3399
+
       - description: GeekBuying GeekBox
         items:
           - const: geekbuying,geekbox

arch/arm64/boot/dts/rockchip/Makefile

@@ -16,6 +16,7 @@ dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399-gru-bob.dtb
 dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399-gru-kevin.dtb
 dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399-gru-scarlet-inx.dtb
 dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399-gru-scarlet-kd.dtb
+dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399-nanopc-t4.dtb
 dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399-puma-haikou.dtb
 dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399-roc-pc.dtb
 dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399-rock960.dtb

arch/arm64/boot/dts/rockchip/rk3399-nanopc-t4.dts

@@ -0,0 +1,17 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * FriendlyElec NanoPC-T4 board device tree source
+ *
+ * Copyright (c) 2018 FriendlyElec Computer Tech. Co., Ltd.
+ * (http://www.friendlyarm.com)
+ *
+ * Copyright (c) 2018 Collabora Ltd.
+ */
+
+/dts-v1/;
+#include "rk3399-nanopi4.dtsi"
+
+/ {
+	model = "FriendlyElec NanoPC-T4";
+	compatible = "friendlyarm,nanopc-t4", "rockchip,rk3399";
+};