rockchip: add ArmSom Sige3 (RK3568 ARM64 4 cores) support

package/boot/uboot-rockchip/Makefile

@@ -309,6 +309,17 @@ define U-Boot/seewo-sv21-rk3568
   DDR:=rk3568_ddr_1560MHz_v1.18.bin
 endef
 
+define U-Boot/sige3-rk3568
+  BUILD_SUBTARGET:=armv8
+  NAME:=Sige3
+  BUILD_DEVICES:= \
+    armsom_sige3
+  DEPENDS:=+PACKAGE_u-boot-sige3-rk3568:arm-trusted-firmware-rk3568
+  PKG_BUILD_DEPENDS:=arm-trusted-firmware-rockchip-vendor
+  ATF:=rk3568_bl31_v1.43.elf
+  DDR:=rk3568_ddr_1560MHz_v1.18.bin
+endef
+
 define U-Boot/station-p2-rk3568
   BUILD_SUBTARGET:=armv8
   NAME:=StationP2
@@ -341,6 +352,7 @@ UBOOT_TARGETS := \
   rock-3a-rk3568 \
   r66s-rk3568 \
   seewo-sv21-rk3568 \
+  sige3-rk3568 \
   station-p2-rk3568 \
   panther-x2-rk3566 \
   sv901-eaio-rk3399 \

package/boot/uboot-rockchip/patches/900-arm-add-dts-files.patch

@@ -0,0 +1,10 @@
+--- a/arch/arm/dts/Makefile
++++ b/arch/arm/dts/Makefile
+@@ -177,6 +177,7 @@
+ dtb-$(CONFIG_ROCKCHIP_RK3568) += \
+ 	rk3566-anbernic-rgxx3.dtb \
+ 	rk3566-radxa-cm3-io.dtb \
++	rk3568-armsom-sige3.dtb \
+ 	rk3568-mrkaio-m68s.dtb \
+ 	rk3568-nanopi-r5s.dtb \
+ 	rk3568-photonicat.dtb \

package/boot/uboot-rockchip/src/arch/arm/dts/rk3568-armsom-sige3-u-boot.dtsi

@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0-or-later OR MIT
+/*
+ * Copyright (c) 2024 Tianling Shen <cnsztl@gmail.com>
+ */
+
+#include "rk356x-u-boot.dtsi"
+
+&sdhci {
+	cap-mmc-highspeed;
+	mmc-ddr-1_8v;
+	mmc-hs200-1_8v;
+	mmc-hs400-1_8v;
+	mmc-hs400-enhanced-strobe;
+	pinctrl-0 = <&emmc_bus8 &emmc_clk &emmc_cmd &emmc_datastrobe>;
+};
+
+&vcc5v0_usb_host {
+	/delete-property/ regulator-always-on;
+	/delete-property/ regulator-boot-on;
+};
+
+&vcc5v0_usb_host2 {
+	/delete-property/ regulator-always-on;
+	/delete-property/ regulator-boot-on;
+};