xref: /freebsd/sys/contrib/device-tree/Bindings/interrupt-controller/img,meta-intc.txt (revision 02e9120893770924227138ba49df1edb3896112a)
1* Meta External Trigger Controller Binding
2
3This binding specifies what properties must be available in the device tree
4representation of a Meta external trigger controller.
5
6Required properties:
7
8    - compatible: Specifies the compatibility list for the interrupt controller.
9      The type shall be <string> and the value shall include "img,meta-intc".
10
11    - num-banks: Specifies the number of interrupt banks (each of which can
12      handle 32 interrupt sources).
13
14    - interrupt-controller: The presence of this property identifies the node
15      as an interrupt controller. No property value shall be defined.
16
17    - #interrupt-cells: Specifies the number of cells needed to encode an
18      interrupt source. The type shall be a <u32> and the value shall be 2.
19
20    - #address-cells: Specifies the number of cells needed to encode an
21      address. The type shall be <u32> and the value shall be 0. As such,
22      'interrupt-map' nodes do not have to specify a parent unit address.
23
24Optional properties:
25
26    - no-mask: The controller doesn't have any mask registers.
27
28* Interrupt Specifier Definition
29
30  Interrupt specifiers consists of 2 cells encoded as follows:
31
32    - <1st-cell>: The interrupt-number that identifies the interrupt source.
33
34    - <2nd-cell>: The Linux interrupt flags containing level-sense information,
35                  encoded as follows:
36                    1 = edge triggered
37                    4 = level-sensitive
38
39* Examples
40
41Example 1:
42
43	/*
44	 * Meta external trigger block
45	 */
46	intc: intc {
47		// This is an interrupt controller node.
48		interrupt-controller;
49
50		// No address cells so that 'interrupt-map' nodes which
51		// reference this interrupt controller node do not need a parent
52		// address specifier.
53		#address-cells = <0>;
54
55		// Two cells to encode interrupt sources.
56		#interrupt-cells = <2>;
57
58		// Number of interrupt banks
59		num-banks = <2>;
60
61		// No HWMASKEXT is available (specify on Chorus2 and Comet ES1)
62		no-mask;
63
64		// Compatible with Meta hardware trigger block.
65		compatible = "img,meta-intc";
66	};
67
68Example 2:
69
70	/*
71	 * An interrupt generating device that is wired to a Meta external
72	 * trigger block.
73	 */
74	uart1: uart@02004c00 {
75		// Interrupt source '5' that is level-sensitive.
76		// Note that there are only two cells as specified in the
77		// interrupt parent's '#interrupt-cells' property.
78		interrupts = <5 4 /* level */>;
79
80		// The interrupt controller that this device is wired to.
81		interrupt-parent = <&intc>;
82	};
83