1* ARC-HS Interrupt Distribution Unit 2 3 This optional 2nd level interrupt controller can be used in SMP configurations 4 for dynamic IRQ routing, load balancing of common/external IRQs towards core 5 intc. 6 7Properties: 8 9- compatible: "snps,archs-idu-intc" 10- interrupt-controller: This is an interrupt controller. 11- #interrupt-cells: Must be <1> or <2>. 12 13 Value of the first cell specifies the "common" IRQ from peripheral to IDU. 14 Number N of the particular interrupt line of IDU corresponds to the line N+24 15 of the core interrupt controller. 16 17 The (optional) second cell specifies any of the following flags: 18 - bits[3:0] trigger type and level flags 19 1 = low-to-high edge triggered 20 2 = NOT SUPPORTED (high-to-low edge triggered) 21 4 = active high level-sensitive <<< DEFAULT 22 8 = NOT SUPPORTED (active low level-sensitive) 23 When no second cell is specified, the interrupt is assumed to be level 24 sensitive. 25 26 The interrupt controller is accessed via the special ARC AUX register 27 interface, hence "reg" property is not specified. 28 29Example: 30 core_intc: core-interrupt-controller { 31 compatible = "snps,archs-intc"; 32 interrupt-controller; 33 #interrupt-cells = <1>; 34 }; 35 36 idu_intc: idu-interrupt-controller { 37 compatible = "snps,archs-idu-intc"; 38 interrupt-controller; 39 interrupt-parent = <&core_intc>; 40 #interrupt-cells = <1>; 41 }; 42 43 some_device: serial@c0fc1000 { 44 interrupt-parent = <&idu_intc>; 45 interrupts = <0>; /* upstream idu IRQ #24 */ 46 }; 47