arm64: dts: rockchip: add ROCK Pi 4 DTS support

ROCK Pi 4 is RK3399 based SBC from radxa.com. board has a 1G/2G/4G lpddr4, CSI,
DSI, HDMI, OTG, USB 2.0, USB 3.0, 10/100/1000 RGMII Ethernet Phy, es8316 codec,
POE, WIFI (for Model B only), PCIE M.2 support on board.

This patch enables
- HDMI Display
- Console
- MMC, EMMC
- USB 2.0, USB-3.0
- Ethernet
Signed-off-by: Akash Gajjar <Akash_Gajjar@mentor.com>
Signed-off-by: Pragnesh Patel <Pragnesh_Patel@mentor.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Heiko Stuebner <heiko@sntech.de>

Documentation/devicetree/bindings/arm/rockchip.yaml

@@ -322,6 +322,11 @@ properties:
           - const: radxa,rock
           - const: rockchip,rk3188
 
+      - description: Radxa ROCK Pi 4
+        items:
+          - const: radxa,rockpi4
+          - const: rockchip,rk3399
+
       - description: Radxa Rock2 Square
         items:
           - const: radxa,rock2-square

arch/arm64/boot/dts/rockchip/Makefile

@@ -19,6 +19,7 @@ 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-$(CONFIG_ARCH_ROCKCHIP) += rk3399-rock-pi-4.dtb
 dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399-rock960.dtb
 dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399-rockpro64.dtb
 dtb-$(CONFIG_ARCH_ROCKCHIP) += rk3399-sapphire.dtb