arm: mach-mvebu: add documentation for new device tree bindings

Signed-off-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Signed-off-by: Lior Amsalem <alior@marvell.com>
Tested-by: Yehuda Yitschak <yehuday@marvell.com>
Tested-by: Lior Amsalem <alior@marvell.com>
Acked-by: Andrew Lunn <andrew@lunn.ch>
diff --git a/Documentation/devicetree/bindings/arm/armada-370-xp.txt b/Documentation/devicetree/bindings/arm/armada-370-xp.txt
new file mode 100644
index 0000000..c6ed90e
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/armada-370-xp.txt
@@ -0,0 +1,24 @@
+Marvell Armada 370 and Armada XP Platforms Device Tree Bindings
+---------------------------------------------------------------
+
+Boards with a SoC of the Marvell Armada 370 and Armada XP families
+shall have the following property:
+
+Required root node property:
+
+compatible: must contain "marvell,armada-370-xp"
+
+In addition, boards using the Marvell Armada 370 SoC shall have the
+following property:
+
+Required root node property:
+
+compatible: must contain "marvell,armada370"
+
+In addition, boards using the Marvell Armada XP SoC shall have the
+following property:
+
+Required root node property:
+
+compatible: must contain "marvell,armadaxp"
+