irqchip: Add TB10x interrupt controller driver

The SOC interrupt controller driver for the Abilis Systems TB10x series of
SOCs based on ARC700 CPUs.

Signed-off-by: Christian Ruppert <christian.ruppert@abilis.com>
Signed-off-by: Pierrick Hascoet <pierrick.hascoet@abilis.com>
Cc: Vineet Gupta <Vineet.Gupta1@synopsys.com>
Cc: Grant Likely <grant.likely@secretlab.ca>
Cc: Rob Herring <rob.herring@calxeda.com>
Cc: Rob Landley <rob@landley.net>
Cc: devicetree-discuss@lists.ozlabs.org
Link: http://lkml.kernel.org/r/1372177797-9458-1-git-send-email-christian.ruppert@abilis.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Documentation/devicetree/bindings/interrupt-controller/abilis,tb10x-ictl.txt

@@ -0,0 +1,38 @@
+TB10x Top Level Interrupt Controller
+====================================
+
+The Abilis TB10x SOC contains a custom interrupt controller. It performs
+one-to-one mapping of external interrupt sources to CPU interrupts and
+provides support for reconfigurable trigger modes.
+
+Required properties
+-------------------
+
+- compatible: Should be "abilis,tb10x-ictl"
+- reg: specifies physical base address and size of register range.
+- interrupt-congroller: Identifies the node as an interrupt controller.
+- #interrupt cells: Specifies the number of cells used to encode an interrupt
+  source connected to this controller. The value shall be 2.
+- interrupt-parent: Specifies the parent interrupt controller.
+- interrupts: Specifies the list of interrupt lines which are handled by
+  the interrupt controller in the parent controller's notation. Interrupts
+  are mapped one-to-one to parent interrupts.
+
+Example
+-------
+
+intc: interrupt-controller {	/* Parent interrupt controller */
+	interrupt-controller;
+	#interrupt-cells = <1>;	/* For example below */
+	/* ... */
+};
+
+tb10x_ictl: pic@2000 {		/* TB10x interrupt controller */
+	compatible = "abilis,tb10x-ictl";
+	reg = <0x2000 0x20>;
+	interrupt-controller;
+	#interrupt-cells = <2>;
+	interrupt-parent = <&intc>;
+	interrupts = <5 6 7 8 9 10 11 12 13 14 15 16 17 18 19
+			20 21 22 23 24 25 26 27 28 29 30 31>;
+};