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+* ARM Versatile FPGA interrupt controller
+
+One or more FPGA IRQ controllers can be synthesized in an ARM reference board
+such as the Integrator or Versatile family. The output of these different
+controllers are OR:ed together and fed to the CPU tile's IRQ input. Each
+instance can handle up to 32 interrupts.
+
+Required properties:
+- compatible: "arm,versatile-fpga-irq"
+- interrupt-controller: Identifies the node as an interrupt controller
+- #interrupt-cells: The number of cells to define the interrupts. Must be 1
+ as the FPGA IRQ controller has no configuration options for interrupt
+ sources. The cell is a u32 and defines the interrupt number.
+- reg: The register bank for the FPGA interrupt controller.
+- clear-mask: a u32 number representing the mask written to clear all IRQs
+ on the controller at boot for example.
+- valid-mask: a u32 number representing a bit mask determining which of
+ the interrupts are valid. Unconnected/unused lines are set to 0, and
+ the system till not make it possible for devices to request these
+ interrupts.
+
+Example:
+
+pic: pic@14000000 {
+ compatible = "arm,versatile-fpga-irq";
+ #interrupt-cells = <1>;
+ interrupt-controller;
+ reg = <0x14000000 0x100>;
+ clear-mask = <0xffffffff>;
+ valid-mask = <0x003fffff>;
+};
+
+Optional properties:
+- interrupts: if the FPGA IRQ controller is cascaded, i.e. if its IRQ
+ output is simply connected to the input of another IRQ controller,
+ then the parent IRQ shall be specified in this property.