board: rockchip: Add Pine64 SOQuartz on Model A

The Pine64 SOQuartz Model A board is a carrier board for the SOQuartz
CM4-compatible compute module. It exposes PCIe, ethernet, USB, HDMI,
CSI, DSI, eDP and a 40 pin GPIO header, and is powered by 12V DC.

Features tested with a SOQuartz 4GB v1.1 2022-07-11:
- SD-card boot
- eMMC boot
- PCIe/NVMe/AHCI
- USB host

Device tree is imported from linux v6.4.

Co-developed-by: Nicolas Frattaroli <frattaroli.nicolas@gmail.com>
Signed-off-by: Nicolas Frattaroli <frattaroli.nicolas@gmail.com>
Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
diff --git a/arch/arm/dts/rk3566-soquartz-u-boot.dtsi b/arch/arm/dts/rk3566-soquartz-u-boot.dtsi
new file mode 100644
index 0000000..793cca2
--- /dev/null
+++ b/arch/arm/dts/rk3566-soquartz-u-boot.dtsi
@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-2.0+
+
+#include "rk356x-u-boot.dtsi"
+
+/ {
+	chosen {
+		stdout-path = &uart2;
+	};
+};
+
+&sdhci {
+	cap-mmc-highspeed;
+	mmc-ddr-1_8v;
+	pinctrl-names = "default";
+	pinctrl-0 = <&emmc_bus8 &emmc_clk &emmc_cmd &emmc_datastrobe>;
+};
+
+&uart2 {
+	bootph-all;
+	clock-frequency = <24000000>;
+	status = "okay";
+};
+
+&usb_host0_xhci {
+	dr_mode = "host";
+};