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diff --git a/sys/boot/fdt/dts/bindings-gpio.txt b/sys/boot/fdt/dts/bindings-gpio.txt
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index 000000000000..b13078aeb0b3
--- /dev/null
+++ b/sys/boot/fdt/dts/bindings-gpio.txt
@@ -0,0 +1,101 @@
+$FreeBSD$
+
+GPIO configuration.
+===================
+
+1. Properties for GPIO Controllers
+
+1.1 #gpio-cells
+
+Property:	#gpio-cells
+
+Value type:	<u32>
+
+Description:	The #gpio-cells property defines the number of cells required
+		to encode a gpio specifier.
+
+
+1.2 gpio-controller
+
+Property:	gpio-controller
+
+Value type:	<empty>
+
+Description:	The presence of a gpio-controller property defines a node as a
+		GPIO controller node.
+
+
+1.3 pin-count
+
+Property:	pin-count
+
+Value type:	<u32>
+
+Description:	The pin-count property defines the number of GPIO pins.
+
+
+1.4 Example
+
+	GPIO: gpio@10100 {
+		#gpio-cells = <3>;
+		compatible = "mrvl,gpio";
+		reg = <0x10100 0x20>;
+		gpio-controller;
+		interrupts = <6 7 8 9>;
+		interrupt-parent = <&PIC>;
+		pin-count = <50>
+	};
+
+2. Properties for GPIO consumer nodes.
+
+2.1 gpios
+
+Property:	gpios
+
+Value type:	<prop-encoded-array> encoded as arbitrary number of GPIO
+		specifiers.
+
+Description:	The gpios property of a device node defines the GPIO or GPIOs
+		that are used by the device. The value of the gpios property
+		consists of an arbitrary number of GPIO specifiers.
+		
+		The first cell of the GPIO specifier is phandle of the node's
+		parent GPIO controller and remaining cells are defined by the
+		binding describing the GPIO parent, typically include
+		information like pin number, direction and various flags.
+
+Example:
+		gpios = <&GPIO 0 1 0		/* GPIO[0]:  IN,  NONE */
+			 &GPIO 1 2 0>;		/* GPIO[1]:  OUT, NONE */
+
+
+3. "mrvl,gpio" controller GPIO specifier
+
+	<phandle pin dir flags>
+
+
+pin:	0-MAX				GPIO pin number.
+
+dir:
+	1		IN		Input direction.
+	2		OUT		Output direction.
+
+flags:
+	0x0000----	IN_NONE
+	0x0001----	IN_POL_LOW	Polarity low (active-low).
+	0x0002----	IN_IRQ_EDGE	Interrupt, edge triggered.
+	0x0004----	IN_IRQ_LEVEL	Interrupt, level triggered.
+	
+	0x----0000	OUT_NONE
+	0x----0001	OUT_BLINK	Blink on the pin.
+	0x----0002	OUT_OPEN_DRAIN	Open drain output line.
+	0x----0004	OUT_OPEN_SRC	Open source output line.
+
+
+Example:
+	gpios = <&GPIO 0  1 0x00000000		/* GPIO[0]:   IN */
+		 &GPIO 1  2 0x00000000		/* GPIO[1]:   OUT */
+		 &GPIO 2  1 0x00020000		/* GPIO[2]:   IN, IRQ (edge) */
+		 &GPIO 3  1 0x00040000		/* GPIO[3]:   IN, IRQ (level) */
+		 ...
+		 &GPIO 10 2 0x00000001>;	/* GPIO[10]:  OUT, blink */