arm64: dts: renesas: Add initial support for RZ/G3S SMARC SoM

Add initial support for the RZ/G3S SMARC SoM.  The following devices
available on the SoM are added to this initial device tree:
  - RZ/G3S SoC: Renesas R9A08G045S33GBG
  - Clock Generator (only 24MHz output): Renesas 5L35023B
  - 1GiB LPDDR4 SDRAM: Micron MT53D512M16D1DS-046
  - 64GB eMMC Flash (though SD ch0): Micron MTFC64GBCAQTC

SD channel 0 of RZ/G3S is connected to an uSD card interface and an
eMMC.  The selection b/w them is done through a hardware switch.  The DT
will select b/w uSD and eMMC through the SW_SD0_DEV_SEL build flag.
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20230929053915.1530607-25-claudiu.beznea@bp.renesas.comSigned-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

arch/arm64/boot/dts/renesas/rzg3s-smarc-som.dtsi

+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/*
+ * Device Tree Source for the R9A08G045S33 SMARC Carrier-II's SoM board.
+ *
+ * Copyright (C) 2023 Renesas Electronics Corp.
+ */
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/pinctrl/rzg2l-pinctrl.h>
+
+/*
+ * Signals of SW_CONFIG switches:
+ * @SW_SD0_DEV_SEL:
+ *	0 - SD0 is connected to eMMC
+ *	1 - SD0 is connected to uSD0 card
+ */
+#define SW_SD0_DEV_SEL	1
+
+/ {
+	compatible = "renesas,rzg3s-smarcm", "renesas,r9a08g045s33", "renesas,r9a08g045";
+
+	aliases {
+		mmc0 = &sdhi0;
+	};
+
+	chosen {
+		bootargs = "ignore_loglevel";
+		stdout-path = "serial0:115200n8";
+	};
+
+	memory@48000000 {
+		device-type = "memory";
+		/* First 128MB is reserved for secure area. */
+		reg = <0x0 0x48000000 0x0 0x38000000>;
+	};
+
+	vcc_sdhi0: regulator0 {
+		compatible = "regulator-fixed";
+		regulator-name = "SDHI0 Vcc";
+		regulator-min-microvolt = <3300000>;
+		regulator-max-microvolt = <3300000>;
+		gpios = <&pinctrl RZG2L_GPIO(2, 1) GPIO_ACTIVE_HIGH>;
+		enable-active-high;
+	};
+
+#if SW_SD0_DEV_SEL
+	vccq_sdhi0: regulator1 {
+		compatible = "regulator-gpio";
+		regulator-name = "SDHI0 VccQ";
+		regulator-min-microvolt = <1800000>;
+		regulator-max-microvolt = <3300000>;
+		gpios = <&pinctrl RZG2L_GPIO(2, 2) GPIO_ACTIVE_HIGH>;
+		gpios-states = <1>;
+		states = <3300000 1>, <1800000 0>;
+	};
+#else
+	reg_1p8v: regulator1 {
+		compatible = "regulator-fixed";
+		regulator-name = "fixed-1.8V";
+		regulator-min-microvolt = <1800000>;
+		regulator-max-microvolt = <1800000>;
+		regulator-boot-on;
+		regulator-always-on;
+	};
+#endif
+};
+
+&extal_clk {
+	clock-frequency = <24000000>;
+};
+
+#if SW_SD0_DEV_SEL
+/* SD0 slot */
+&sdhi0 {
+	pinctrl-0 = <&sdhi0_pins>;
+	pinctrl-1 = <&sdhi0_uhs_pins>;
+	pinctrl-names = "default", "state_uhs";
+	vmmc-supply = <&vcc_sdhi0>;
+	vqmmc-supply = <&vccq_sdhi0>;
+	bus-width = <4>;
+	sd-uhs-sdr50;
+	sd-uhs-sdr104;
+	max-frequency = <125000000>;
+	status = "okay";
+};
+#else
+/* eMMC */
+&sdhi0 {
+	pinctrl-0 = <&sdhi0_emmc_pins>;
+	pinctrl-1 = <&sdhi0_emmc_pins>;
+	pinctrl-names = "default", "state_uhs";
+	vmmc-supply = <&vcc_sdhi0>;
+	vqmmc-supply = <&reg_1p8v>;
+	bus-width = <8>;
+	mmc-hs200-1_8v;
+	non-removable;
+	fixed-emmc-driver-type = <1>;
+	max-frequency = <125000000>;
+	status = "okay";
+};
+#endif
+
+&pinctrl {
+	sdhi0_pins: sd0 {
+		data {
+			pins = "SD0_DATA0", "SD0_DATA1", "SD0_DATA2", "SD0_DATA3";
+			power-source = <3300>;
+		};
+
+		ctrl {
+			pins = "SD0_CLK", "SD0_CMD";
+			power-source = <3300>;
+		};
+
+		cd {
+			pinmux = <RZG2L_PORT_PINMUX(0, 0, 1)>; /* SD0_CD */
+		};
+	};
+
+	sdhi0_uhs_pins: sd0-uhs {
+		data {
+			pins = "SD0_DATA0", "SD0_DATA1", "SD0_DATA2", "SD0_DATA3";
+			power-source = <1800>;
+		};
+
+		ctrl {
+			pins = "SD0_CLK", "SD0_CMD";
+			power-source = <1800>;
+		};
+
+		cd {
+			pinmux = <RZG2L_PORT_PINMUX(0, 0, 1)>; /* SD0_CD */
+		};
+	};
+
+	sdhi0_emmc_pins: sd0-emmc {
+		pins = "SD0_DATA0", "SD0_DATA1", "SD0_DATA2", "SD0_DATA3",
+		       "SD0_DATA4", "SD0_DATA5", "SD0_DATA6", "SD0_DATA7",
+		       "SD0_CLK", "SD0_CMD", "SD0_RST#";
+		power-source = <1800>;
+	};
+};