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+C6X Interrupt Chips
+-------------------
+
+* C64X+ Core Interrupt Controller
+
+ The core interrupt controller provides 16 prioritized interrupts to the
+ C64X+ core. Priority 0 and 1 are used for reset and NMI respectively.
+ Priority 2 and 3 are reserved. Priority 4-15 are used for interrupt
+ sources coming from outside the core.
+
+ Required properties:
+ --------------------
+ - compatible: Should be "ti,c64x+core-pic";
+ - #interrupt-cells: <1>
+
+ Interrupt Specifier Definition
+ ------------------------------
+ Single cell specifying the core interrupt priority level (4-15) where
+ 4 is highest priority and 15 is lowest priority.
+
+ Example
+ -------
+ core_pic: interrupt-controller@0 {
+ interrupt-controller;
+ #interrupt-cells = <1>;
+ compatible = "ti,c64x+core-pic";
+ };
+
+
+
+* C64x+ Megamodule Interrupt Controller
+
+ The megamodule PIC consists of four interrupt mupliplexers each of which
+ combine up to 32 interrupt inputs into a single interrupt output which
+ may be cascaded into the core interrupt controller. The megamodule PIC
+ has a total of 12 outputs cascading into the core interrupt controller.
+ One for each core interrupt priority level. In addition to the combined
+ interrupt sources, individual megamodule interrupts may be cascaded to
+ the core interrupt controller. When an individual interrupt is cascaded,
+ it is no longer handled through a megamodule interrupt combiner and is
+ considered to have the core interrupt controller as the parent.
+
+ Required properties:
+ --------------------
+ - compatible: "ti,c64x+megamod-pic"
+ - interrupt-controller
+ - #interrupt-cells: <1>
+ - reg: base address and size of register area
+ - interrupt-parent: must be core interrupt controller
+ - interrupts: This should have four cells; one for each interrupt combiner.
+ The cells contain the core priority interrupt to which the
+ corresponding combiner output is wired.
+
+ Optional properties:
+ --------------------
+ - ti,c64x+megamod-pic-mux: Array of 12 cells correspnding to the 12 core
+ priority interrupts. The first cell corresponds to
+ core priority 4 and the last cell corresponds to
+ core priority 15. The value of each cell is the
+ megamodule interrupt source which is MUXed to
+ the core interrupt corresponding to the cell
+ position. Allowed values are 4 - 127. Mapping for
+ interrupts 0 - 3 (combined interrupt sources) are
+ ignored.
+
+ Interrupt Specifier Definition
+ ------------------------------
+ Single cell specifying the megamodule interrupt source (4-127). Note that
+ interrupts mapped directly to the core with "ti,c64x+megamod-pic-mux" will
+ use the core interrupt controller as their parent and the specifier will
+ be the core priority level, not the megamodule interrupt number.
+
+ Examples
+ --------
+ megamod_pic: interrupt-controller@1800000 {
+ compatible = "ti,c64x+megamod-pic";
+ interrupt-controller;
+ #interrupt-cells = <1>;
+ reg = <0x1800000 0x1000>;
+ interrupt-parent = <&core_pic>;
+ interrupts = < 12 13 14 15 >;
+ };
+
+ This is a minimal example where all individual interrupts go through a
+ combiner. Combiner-0 is mapped to core interrupt 12, combiner-1 is mapped
+ to interrupt 13, etc.
+
+
+ megamod_pic: interrupt-controller@1800000 {
+ compatible = "ti,c64x+megamod-pic";
+ interrupt-controller;
+ #interrupt-cells = <1>;
+ reg = <0x1800000 0x1000>;
+ interrupt-parent = <&core_pic>;
+ interrupts = < 12 13 14 15 >;
+ ti,c64x+megamod-pic-mux = < 0 0 0 0
+ 32 0 0 0
+ 0 0 0 0 >;
+ };
+
+ This the same as the first example except that megamodule interrupt 32 is
+ mapped directly to core priority interrupt 8. The node using this interrupt
+ must set the core controller as its interrupt parent and use 8 in the
+ interrupt specifier value.