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-rw-r--r--Documentation/devicetree/bindings/interrupt-controller/microchip,pic32-evic.txt67
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+Microchip PIC32 Interrupt Controller
+====================================
+
+The Microchip PIC32 contains an Enhanced Vectored Interrupt Controller (EVIC).
+It handles all internal and external interrupts. This controller exists outside
+of the CPU and is the arbitrator of all interrupts (including interrupts from
+the CPU itself) before they are presented to the CPU.
+
+External interrupts have a software configurable edge polarity. Non external
+interrupts have a type and polarity that is determined by the source of the
+interrupt.
+
+Required properties
+-------------------
+
+- compatible: Should be "microchip,pic32mzda-evic"
+- reg: Specifies physical base address and size of register range.
+- interrupt-controller: 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 and interrupt
+ descriptor shall have the following format:
+
+ <hw_irq irq_type>
+
+ hw_irq - represents the hardware interrupt number as in the data sheet.
+ irq_type - is used to describe the type and polarity of an interrupt. For
+ internal interrupts use IRQ_TYPE_EDGE_RISING for non persistent interrupts and
+ IRQ_TYPE_LEVEL_HIGH for persistent interrupts. For external interrupts use
+ IRQ_TYPE_EDGE_RISING or IRQ_TYPE_EDGE_FALLING to select the desired polarity.
+
+Optional properties
+-------------------
+- microchip,external-irqs: u32 array of external interrupts with software
+ polarity configuration. This array corresponds to the bits in the INTCON
+ SFR.
+
+Example
+-------
+
+evic: interrupt-controller@1f810000 {
+ compatible = "microchip,pic32mzda-evic";
+ interrupt-controller;
+ #interrupt-cells = <2>;
+ reg = <0x1f810000 0x1000>;
+ microchip,external-irqs = <3 8 13 18 23>;
+};
+
+Each device/peripheral must request its interrupt line with the associated type
+and polarity.
+
+Internal interrupt DTS snippet
+------------------------------
+
+device@1f800000 {
+ ...
+ interrupts = <113 IRQ_TYPE_LEVEL_HIGH>;
+ ...
+};
+
+External interrupt DTS snippet
+------------------------------
+
+device@1f800000 {
+ ...
+ interrupts = <3 IRQ_TYPE_EDGE_RISING>;
+ ...
+};