irqchip/mvebu-odmi: Add new driver for platform MSI on Marvell 7K/8K

This commits adds a new irqchip driver that handles the ODMI
controller found on Marvell 7K/8K processors. The ODMI controller
provide MSI interrupt functionality to on-board peripherals, much like
the GIC-v2m.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/1455888883-5127-1-git-send-email-thomas.petazzoni@free-electrons.com
Signed-off-by: Jason Cooper <jason@lakedaemon.net>

Documentation/devicetree/bindings/interrupt-controller/marvell,odmi-controller.txt

@@ -0,0 +1,41 @@
+
+* Marvell ODMI for MSI support
+
+Some Marvell SoCs have an On-Die Message Interrupt (ODMI) controller
+which can be used by on-board peripheral for MSI interrupts.
+
+Required properties:
+
+- compatible           : The value here should contain "marvell,odmi-controller".
+
+- interrupt,controller : Identifies the node as an interrupt controller.
+
+- msi-controller       : Identifies the node as an MSI controller.
+
+- marvell,odmi-frames  : Number of ODMI frames available. Each frame
+                         provides a number of events.
+
+- reg                  : List of register definitions, one for each
+                         ODMI frame.
+
+- marvell,spi-base     : List of GIC base SPI interrupts, one for each
+                         ODMI frame. Those SPI interrupts are 0-based,
+                         i.e marvell,spi-base = <128> will use SPI #96.
+                         See Documentation/devicetree/bindings/interrupt-controller/arm,gic.txt
+                         for details about the GIC Device Tree binding.
+
+- interrupt-parent     : Reference to the parent interrupt controller.
+
+Example:
+
+	odmi: odmi@300000 {
+		compatible = "marvell,odmi-controller";
+		interrupt-controller;
+		msi-controller;
+		marvell,odmi-frames = <4>;
+		reg = <0x300000 0x4000>,
+		      <0x304000 0x4000>,
+		      <0x308000 0x4000>,
+		      <0x30C000 0x4000>;
+		marvell,spi-base = <128>, <136>, <144>, <152>;
+	};