ARM: dts: Add minimal Raspberry Pi 4 support

This adds minimal support for the new Raspberry Pi 4 without the
fancy stuff like GENET, PCIe, xHCI, 40 bit DMA and V3D. The RPi 4 is
available in 3 different variants (1, 2 and 4 GB RAM), so leave the memory
size to zero and let the bootloader take care of it. The DWC2 is still
usable as peripheral via the USB-C port.

Other differences to the Raspberry Pi 3:
- additional GIC 400 Interrupt controller
- new thermal IP and HWRNG
- additional MMC interface (emmc2)
- additional UART, I2C, SPI and PWM interfaces
- clock stretching bug in I2C IP has been fixed

Signed-off-by: Stefan Wahren <wahrenst@gmx.net>
Acked-by: Eric Anholt <eric@anholt.net>
Acked-by: Florian Fanelli <f.fainelli@gmail.com>
diff --git a/arch/arm/boot/dts/bcm2711-rpi-4-b.dts b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
new file mode 100644
index 0000000..cccc1cc
--- /dev/null
+++ b/arch/arm/boot/dts/bcm2711-rpi-4-b.dts
@@ -0,0 +1,123 @@
+// SPDX-License-Identifier: GPL-2.0
+/dts-v1/;
+#include "bcm2711.dtsi"
+#include "bcm2835-rpi.dtsi"
+#include "bcm283x-rpi-usb-peripheral.dtsi"
+
+/ {
+	compatible = "raspberrypi,4-model-b", "brcm,bcm2711";
+	model = "Raspberry Pi 4 Model B";
+
+	chosen {
+		/* 8250 auxiliary UART instead of pl011 */
+		stdout-path = "serial1:115200n8";
+	};
+
+	/* Will be filled by the bootloader */
+	memory@0 {
+		device_type = "memory";
+		reg = <0 0 0>;
+	};
+
+	leds {
+		act {
+			gpios = <&gpio 42 GPIO_ACTIVE_HIGH>;
+		};
+
+		pwr {
+			label = "PWR";
+			gpios = <&expgpio 2 GPIO_ACTIVE_LOW>;
+		};
+	};
+
+	wifi_pwrseq: wifi-pwrseq {
+		compatible = "mmc-pwrseq-simple";
+		reset-gpios = <&expgpio 1 GPIO_ACTIVE_LOW>;
+	};
+
+	sd_io_1v8_reg: sd_io_1v8_reg {
+		compatible = "regulator-gpio";
+		regulator-name = "vdd-sd-io";
+		regulator-min-microvolt = <1800000>;
+		regulator-max-microvolt = <3300000>;
+		regulator-boot-on;
+		regulator-always-on;
+		regulator-settling-time-us = <5000>;
+		gpios = <&expgpio 4 GPIO_ACTIVE_HIGH>;
+		states = <1800000 0x1
+			  3300000 0x0>;
+		status = "okay";
+	};
+};
+
+&firmware {
+	expgpio: gpio {
+		compatible = "raspberrypi,firmware-gpio";
+		gpio-controller;
+		#gpio-cells = <2>;
+		gpio-line-names = "BT_ON",
+				  "WL_ON",
+				  "PWR_LED_OFF",
+				  "GLOBAL_RESET",
+				  "VDD_SD_IO_SEL",
+				  "CAM_GPIO",
+				  "",
+				  "";
+		status = "okay";
+	};
+};
+
+&pwm1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&pwm1_0_gpio40 &pwm1_1_gpio41>;
+	status = "okay";
+};
+
+/* SDHCI is used to control the SDIO for wireless */
+&sdhci {
+	#address-cells = <1>;
+	#size-cells = <0>;
+	pinctrl-names = "default";
+	pinctrl-0 = <&emmc_gpio34>;
+	bus-width = <4>;
+	non-removable;
+	mmc-pwrseq = <&wifi_pwrseq>;
+	status = "okay";
+
+	brcmf: wifi@1 {
+		reg = <1>;
+		compatible = "brcm,bcm4329-fmac";
+	};
+};
+
+/* EMMC2 is used to drive the SD card */
+&emmc2 {
+	vqmmc-supply = <&sd_io_1v8_reg>;
+	broken-cd;
+	status = "okay";
+};
+
+/* uart0 communicates with the BT module */
+&uart0 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&uart0_ctsrts_gpio30 &uart0_gpio32>;
+	uart-has-rtscts;
+	status = "okay";
+
+	bluetooth {
+		compatible = "brcm,bcm43438-bt";
+		max-speed = <2000000>;
+		shutdown-gpios = <&expgpio 0 GPIO_ACTIVE_HIGH>;
+	};
+};
+
+/* uart1 is mapped to the pin header */
+&uart1 {
+	pinctrl-names = "default";
+	pinctrl-0 = <&uart1_gpio14>;
+	status = "okay";
+};
+
+&vchiq {
+	interrupts = <GIC_SPI 34 IRQ_TYPE_LEVEL_HIGH>;
+};