arc: Add support for IoT development kit

The DesignWare ARC IoT Development Kit is a versatile platform
that includes the necessary hardware and software to accelerate
software development and debugging of sensor fusion,
voice recognition and face detection designs.

More information is avaialble here [1] and here [2].

The board is based on real silicon with
ARC EM9D-based Data Fusion IP Subsystem.

It sports a rich set of I/O including
 * DW USB OTG
 * DW MobileStorage (used for micro SD-card)
 * GPIO
 * multiple serial interface including DW APB UART
 * ADC, PWM and eFlash, SRAM and SPI Flash memory
 * Real-Time Clock (RTC)
 * Bluetooth module with worldwide regulatory compliance
   (FCC, IC, CE, ETSI, TELEC)
 * On-board 9-axis sensor (gyro, accelerometer and compass)

Extensible with Arduino, Pmod, mikroBUS connectors and a 2x18
extension header.

One of the most interesting features for developers is built-in
Digilent USB JTAG probe so only micro-USB cable is needed!

[1] https://www.synopsys.com/dw/ipdir.php?ds=arc_iot_development_kit
[2] https://www.synopsys.com/dw/doc.php/ds/cc/iot_dev_kit.pdf

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>
diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index d59aa3a..b24593e 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -157,6 +157,10 @@
 config TARGET_HSDK
 	bool "Support Synpsys HS DevelopmentKit board"
 
+config TARGET_IOT_DEVKIT
+	bool "Synopsys Brite IoT Development kit"
+	select CPU_ARCEM6
+
 endchoice
 
 source "board/abilis/tb100/Kconfig"
@@ -164,5 +168,6 @@
 source "board/synopsys/axs10x/Kconfig"
 source "board/synopsys/emdk/Kconfig"
 source "board/synopsys/hsdk/Kconfig"
+source "board/synopsys/iot_devkit/Kconfig"
 
 endmenu
diff --git a/arch/arc/dts/Makefile b/arch/arc/dts/Makefile
index 491a4f4..17e1405 100644
--- a/arch/arc/dts/Makefile
+++ b/arch/arc/dts/Makefile
@@ -6,6 +6,7 @@
 dtb-$(CONFIG_TARGET_TB100) +=  abilis_tb100.dtb
 dtb-$(CONFIG_TARGET_EMDK) +=  emdk.dtb
 dtb-$(CONFIG_TARGET_HSDK) +=  hsdk.dtb
+dtb-$(CONFIG_TARGET_IOT_DEVKIT) +=  iot_devkit.dtb
 
 targets += $(dtb-y)
 
diff --git a/arch/arc/dts/iot_devkit.dts b/arch/arc/dts/iot_devkit.dts
new file mode 100644
index 0000000..ebf5a95
--- /dev/null
+++ b/arch/arc/dts/iot_devkit.dts
@@ -0,0 +1,45 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018 Synopsys, Inc. All rights reserved.
+ */
+/dts-v1/;
+
+#include "skeleton.dtsi"
+
+/ {
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	aliases {
+		console = &uart0;
+	};
+
+	cpu_card {
+		core_clk: core_clk {
+			#clock-cells = <0>;
+			compatible = "fixed-clock";
+			clock-frequency = <144000000>;
+			u-boot,dm-pre-reloc;
+		};
+	};
+
+	uart0: serial0@80014000 {
+		compatible = "snps,dw-apb-uart";
+		clock-frequency = <16000000>;
+		reg = <0x80014000 0x1000>;
+		reg-shift = <2>;
+		reg-io-width = <4>;
+	};
+
+	usb: usb@f0040000 {
+		compatible = "snps,dwc2";
+		reg = <0xf0040000 0x10000>;
+		phys = <&usbphy>;
+		phy-names = "usb2-phy";
+	};
+
+	usbphy: phy {
+		compatible = "nop-phy";
+		#phy-cells = <0>;
+	};
+};