xref: /OK3568_Linux_fs/kernel/Documentation/devicetree/bindings/interrupt-controller/arm,nvic.txt (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun* ARM Nested Vector Interrupt Controller (NVIC)
2*4882a593Smuzhiyun
3*4882a593SmuzhiyunThe NVIC provides an interrupt controller that is tightly coupled to
4*4882a593SmuzhiyunCortex-M based processor cores.  The NVIC implemented on different SoCs
5*4882a593Smuzhiyunvary in the number of interrupts and priority bits per interrupt.
6*4882a593Smuzhiyun
7*4882a593SmuzhiyunMain node required properties:
8*4882a593Smuzhiyun
9*4882a593Smuzhiyun- compatible : should be one of:
10*4882a593Smuzhiyun	"arm,v6m-nvic"
11*4882a593Smuzhiyun	"arm,v7m-nvic"
12*4882a593Smuzhiyun	"arm,v8m-nvic"
13*4882a593Smuzhiyun- interrupt-controller : Identifies the node as an interrupt controller
14*4882a593Smuzhiyun- #interrupt-cells : Specifies the number of cells needed to encode an
15*4882a593Smuzhiyun  interrupt source.  The type shall be a <u32> and the value shall be 2.
16*4882a593Smuzhiyun
17*4882a593Smuzhiyun  The 1st cell contains the interrupt number for the interrupt type.
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun  The 2nd cell is the priority of the interrupt.
20*4882a593Smuzhiyun
21*4882a593Smuzhiyun- reg : Specifies base physical address(s) and size of the NVIC registers.
22*4882a593Smuzhiyun  This is at a fixed address (0xe000e100) and size (0xc00).
23*4882a593Smuzhiyun
24*4882a593Smuzhiyun- arm,num-irq-priority-bits: The number of priority bits implemented by the
25*4882a593Smuzhiyun  given SoC
26*4882a593Smuzhiyun
27*4882a593SmuzhiyunExample:
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun	intc: interrupt-controller@e000e100 {
30*4882a593Smuzhiyun		compatible = "arm,v7m-nvic";
31*4882a593Smuzhiyun		#interrupt-cells = <2>;
32*4882a593Smuzhiyun		#address-cells = <1>;
33*4882a593Smuzhiyun		interrupt-controller;
34*4882a593Smuzhiyun		reg = <0xe000e100 0xc00>;
35*4882a593Smuzhiyun		arm,num-irq-priority-bits = <4>;
36*4882a593Smuzhiyun	};
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