rockchip: rk3568: Add support for FriendlyARM NanoPi R5S

FriendlyARM NanoPi R5S is an open-sourced mini IoT gateway device.

Board Specifications
- Rockchip RK3568
- 2 or 4GB LPDDR4X
- 8GB or 16GB eMMC, SD card slot
- GbE LAN (Native)
- 2x 2.5G LAN (PCIe)
- M.2 Connector
- HDMI 2.0, MIPI DSI/CSI
- 2xUSB 3.0 Host
- USB Type C PD, 5V/9V/12V
- GPIO: 12-pin 0.5mm FPC connector

The device tree is taken from kernel v6.4-rc1.

Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Signed-off-by: Tianling Shen <cnsztl@gmail.com>
diff --git a/configs/nanopi-r5s-rk3568_defconfig b/configs/nanopi-r5s-rk3568_defconfig
new file mode 100644
index 0000000..0a298c6
--- /dev/null
+++ b/configs/nanopi-r5s-rk3568_defconfig
@@ -0,0 +1,85 @@
+CONFIG_ARM=y
+CONFIG_SKIP_LOWLEVEL_INIT=y
+CONFIG_COUNTER_FREQUENCY=24000000
+CONFIG_ARCH_ROCKCHIP=y
+CONFIG_TEXT_BASE=0x00a00000
+CONFIG_SPL_LIBCOMMON_SUPPORT=y
+CONFIG_SPL_LIBGENERIC_SUPPORT=y
+CONFIG_NR_DRAM_BANKS=2
+CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y
+CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0xc00000
+CONFIG_DEFAULT_DEVICE_TREE="rk3568-nanopi-r5s"
+CONFIG_ROCKCHIP_RK3568=y
+CONFIG_SPL_ROCKCHIP_COMMON_BOARD=y
+CONFIG_SPL_SERIAL=y
+CONFIG_SPL_STACK_R_ADDR=0x600000
+CONFIG_TARGET_EVB_RK3568=y
+CONFIG_SPL_STACK=0x400000
+CONFIG_DEBUG_UART_BASE=0xFE660000
+CONFIG_DEBUG_UART_CLOCK=24000000
+CONFIG_SYS_LOAD_ADDR=0xc00800
+CONFIG_DEBUG_UART=y
+CONFIG_FIT=y
+CONFIG_FIT_VERBOSE=y
+CONFIG_SPL_LOAD_FIT=y
+CONFIG_DEFAULT_FDT_FILE="rockchip/rk3568-nanopi-r5s.dtb"
+# CONFIG_DISPLAY_CPUINFO is not set
+CONFIG_DISPLAY_BOARDINFO_LATE=y
+CONFIG_SPL_MAX_SIZE=0x40000
+CONFIG_SPL_PAD_TO=0x7f8000
+CONFIG_SPL_HAS_BSS_LINKER_SECTION=y
+CONFIG_SPL_BSS_START_ADDR=0x4000000
+CONFIG_SPL_BSS_MAX_SIZE=0x4000
+# CONFIG_SPL_RAW_IMAGE_SUPPORT is not set
+# CONFIG_SPL_SHARES_INIT_SP_ADDR is not set
+CONFIG_SPL_STACK_R=y
+CONFIG_SPL_ATF=y
+CONFIG_CMD_GPIO=y
+CONFIG_CMD_GPT=y
+CONFIG_CMD_I2C=y
+CONFIG_CMD_MMC=y
+CONFIG_CMD_USB=y
+CONFIG_CMD_PMIC=y
+CONFIG_CMD_REGULATOR=y
+# CONFIG_SPL_DOS_PARTITION is not set
+CONFIG_SPL_OF_CONTROL=y
+CONFIG_OF_LIVE=y
+CONFIG_OF_SPL_REMOVE_PROPS="pinctrl-0 pinctrl-names clock-names interrupt-parent assigned-clocks assigned-clock-rates assigned-clock-parents"
+CONFIG_SPL_DM_WARN=y
+CONFIG_SPL_REGMAP=y
+CONFIG_SPL_SYSCON=y
+CONFIG_SPL_CLK=y
+CONFIG_ROCKCHIP_GPIO=y
+CONFIG_SYS_I2C_ROCKCHIP=y
+CONFIG_MISC=y
+CONFIG_SUPPORT_EMMC_RPMB=y
+CONFIG_MMC_DW=y
+CONFIG_MMC_DW_ROCKCHIP=y
+CONFIG_MMC_SDHCI=y
+CONFIG_MMC_SDHCI_SDMA=y
+CONFIG_MMC_SDHCI_ROCKCHIP=y
+CONFIG_ETH_DESIGNWARE=y
+CONFIG_GMAC_ROCKCHIP=y
+CONFIG_PHY_ROCKCHIP_INNO_USB2=y
+CONFIG_PHY_ROCKCHIP_NANENG_COMBOPHY=y
+CONFIG_POWER_DOMAIN=y
+CONFIG_DM_PMIC=y
+CONFIG_PMIC_RK8XX=y
+CONFIG_SPL_DM_REGULATOR_FIXED=y
+CONFIG_REGULATOR_RK8XX=y
+CONFIG_PWM_ROCKCHIP=y
+CONFIG_SPL_RAM=y
+CONFIG_BAUDRATE=1500000
+CONFIG_DEBUG_UART_SHIFT=2
+CONFIG_SYS_NS16550_MEM32=y
+CONFIG_SYSRESET=y
+CONFIG_SYSRESET_PSCI=y
+CONFIG_USB=y
+CONFIG_USB_XHCI_HCD=y
+CONFIG_USB_XHCI_DWC3=y
+CONFIG_USB_EHCI_HCD=y
+CONFIG_USB_EHCI_GENERIC=y
+CONFIG_USB_OHCI_HCD=y
+CONFIG_USB_OHCI_GENERIC=y
+CONFIG_USB_DWC3=y
+CONFIG_ERRNO_STR=y