ARM: 7516/1: plat-versatile: add DT support to FPGA IRQ

This adds Device Tree probing support to the Versatile FPGA
IRQ controller.

Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

1 files changed, 31 insertions, 0 deletions

diff --git a/Documentation/devicetree/bindings/arm/versatile-fpga-irq.txt b/Documentation/devicetree/bindings/arm/versatile-fpga-irq.txt
new file mode 100644
index 0000000..9989eda
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/versatile-fpga-irq.txt
@@ -0,0 +1,31 @@
+* 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>;
+};