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diff --git a/Documentation/devicetree/bindings/c6x/interrupt.txt b/Documentation/devicetree/bindings/c6x/interrupt.txt new file mode 100644 index 00000000000..42bb796cc4a --- /dev/null +++ b/Documentation/devicetree/bindings/c6x/interrupt.txt @@ -0,0 +1,104 @@ +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. |