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+* Meta External Trigger Controller Binding
+
+This binding specifies what properties must be available in the device tree
+representation of a Meta external trigger controller.
+
+Required properties:
+
+ - compatible: Specifies the compatibility list for the interrupt controller.
+ The type shall be <string> and the value shall include "img,meta-intc".
+
+ - num-banks: Specifies the number of interrupt banks (each of which can
+ handle 32 interrupt sources).
+
+ - interrupt-controller: The presence of this property identifies the node
+ as an interupt controller. No property value shall be defined.
+
+ - #interrupt-cells: Specifies the number of cells needed to encode an
+ interrupt source. The type shall be a <u32> and the value shall be 2.
+
+ - #address-cells: Specifies the number of cells needed to encode an
+ address. The type shall be <u32> and the value shall be 0. As such,
+ 'interrupt-map' nodes do not have to specify a parent unit address.
+
+Optional properties:
+
+ - no-mask: The controller doesn't have any mask registers.
+
+* Interrupt Specifier Definition
+
+ Interrupt specifiers consists of 2 cells encoded as follows:
+
+ - <1st-cell>: The interrupt-number that identifies the interrupt source.
+
+ - <2nd-cell>: The Linux interrupt flags containing level-sense information,
+ encoded as follows:
+ 1 = edge triggered
+ 4 = level-sensitive
+
+* Examples
+
+Example 1:
+
+ /*
+ * Meta external trigger block
+ */
+ intc: intc {
+ // This is an interrupt controller node.
+ interrupt-controller;
+
+ // No address cells so that 'interrupt-map' nodes which
+ // reference this interrupt controller node do not need a parent
+ // address specifier.
+ #address-cells = <0>;
+
+ // Two cells to encode interrupt sources.
+ #interrupt-cells = <2>;
+
+ // Number of interrupt banks
+ num-banks = <2>;
+
+ // No HWMASKEXT is available (specify on Chorus2 and Comet ES1)
+ no-mask;
+
+ // Compatible with Meta hardware trigger block.
+ compatible = "img,meta-intc";
+ };
+
+Example 2:
+
+ /*
+ * An interrupt generating device that is wired to a Meta external
+ * trigger block.
+ */
+ uart1: uart@0x02004c00 {
+ // Interrupt source '5' that is level-sensitive.
+ // Note that there are only two cells as specified in the
+ // interrupt parent's '#interrupt-cells' property.
+ interrupts = <5 4 /* level */>;
+
+ // The interrupt controller that this device is wired to.
+ interrupt-parent = <&intc>;
+ };