arm64: dts: renesas: gray-hawk-single: Add eMMC support

Describe the eMMC on the Gray Hawk Single board.
Signed-off-by: Cong Dang <cong.dang.xn@renesas.com>
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/208bfc781b1488e253e19626ad80876c34c86758.1707915763.git.geert+renesas@glider.be

arch/arm64/boot/dts/renesas/r8a779h0-gray-hawk-single.dts

@@ -36,6 +36,24 @@ memory@480000000 {
 		device_type = "memory";
 		reg = <0x4 0x80000000 0x1 0x80000000>;
 	};
+
+	reg_1p8v: regulator-1p8v {
+			compatible = "regulator-fixed";
+			regulator-name = "fixed-1.8V";
+			regulator-min-microvolt = <1800000>;
+			regulator-max-microvolt = <1800000>;
+			regulator-boot-on;
+			regulator-always-on;
+	};
+
+	reg_3p3v: regulator-3p3v {
+			compatible = "regulator-fixed";
+			regulator-name = "fixed-3.3V";
+			regulator-min-microvolt = <3300000>;
+			regulator-max-microvolt = <3300000>;
+			regulator-boot-on;
+			regulator-always-on;
+	};
 };
 
 &avb0 {
@@ -108,6 +126,23 @@ eeprom@53 {
 	};
 };
 
+&mmc0 {
+	pinctrl-0 = <&mmc_pins>;
+	pinctrl-1 = <&mmc_pins>;
+	pinctrl-names = "default", "state_uhs";
+
+	vmmc-supply = <&reg_3p3v>;
+	vqmmc-supply = <&reg_1p8v>;
+	mmc-hs200-1_8v;
+	mmc-hs400-1_8v;
+	bus-width = <8>;
+	no-sd;
+	no-sdio;
+	non-removable;
+	full-pwr-cycle-in-suspend;
+	status = "okay";
+};
+
 &pfc {
 	pinctrl-0 = <&scif_clk_pins>;
 	pinctrl-names = "default";
@@ -140,6 +175,12 @@ i2c0_pins: i2c0 {
 		function = "i2c0";
 	};
 
+	mmc_pins: mmc {
+		groups = "mmc_data8", "mmc_ctrl", "mmc_ds";
+		function = "mmc";
+		power-source = <1800>;
+	};
+
 	scif_clk_pins: scif-clk {
 		groups = "scif_clk";
 		function = "scif_clk";