xref: /OK3568_Linux_fs/kernel/Documentation/devicetree/bindings/mips/cpu_irq.txt (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593SmuzhiyunMIPS CPU interrupt controller
2*4882a593Smuzhiyun
3*4882a593SmuzhiyunOn MIPS the mips_cpu_irq_of_init() helper can be used to initialize the 8 CPU
4*4882a593SmuzhiyunIRQs from a devicetree file and create a irq_domain for IRQ controller.
5*4882a593Smuzhiyun
6*4882a593SmuzhiyunWith the irq_domain in place we can describe how the 8 IRQs are wired to the
7*4882a593Smuzhiyunplatforms internal interrupt controller cascade.
8*4882a593Smuzhiyun
9*4882a593SmuzhiyunBelow is an example of a platform describing the cascade inside the devicetree
10*4882a593Smuzhiyunand the code used to load it inside arch_init_irq().
11*4882a593Smuzhiyun
12*4882a593SmuzhiyunRequired properties:
13*4882a593Smuzhiyun- compatible : Should be "mti,cpu-interrupt-controller"
14*4882a593Smuzhiyun
15*4882a593SmuzhiyunExample devicetree:
16*4882a593Smuzhiyun	cpu-irq: cpu-irq {
17*4882a593Smuzhiyun		#address-cells = <0>;
18*4882a593Smuzhiyun
19*4882a593Smuzhiyun		interrupt-controller;
20*4882a593Smuzhiyun		#interrupt-cells = <1>;
21*4882a593Smuzhiyun
22*4882a593Smuzhiyun		compatible = "mti,cpu-interrupt-controller";
23*4882a593Smuzhiyun	};
24*4882a593Smuzhiyun
25*4882a593Smuzhiyun	intc: intc@200 {
26*4882a593Smuzhiyun		compatible = "ralink,rt2880-intc";
27*4882a593Smuzhiyun		reg = <0x200 0x100>;
28*4882a593Smuzhiyun
29*4882a593Smuzhiyun		interrupt-controller;
30*4882a593Smuzhiyun		#interrupt-cells = <1>;
31*4882a593Smuzhiyun
32*4882a593Smuzhiyun		interrupt-parent = <&cpu-irq>;
33*4882a593Smuzhiyun		interrupts = <2>;
34*4882a593Smuzhiyun	};
35*4882a593Smuzhiyun
36*4882a593Smuzhiyun
37*4882a593SmuzhiyunExample platform irq.c:
38*4882a593Smuzhiyunstatic struct of_device_id __initdata of_irq_ids[] = {
39*4882a593Smuzhiyun	{ .compatible = "mti,cpu-interrupt-controller", .data = mips_cpu_irq_of_init },
40*4882a593Smuzhiyun	{ .compatible = "ralink,rt2880-intc", .data = intc_of_init },
41*4882a593Smuzhiyun	{},
42*4882a593Smuzhiyun};
43*4882a593Smuzhiyun
44*4882a593Smuzhiyunvoid __init arch_init_irq(void)
45*4882a593Smuzhiyun{
46*4882a593Smuzhiyun	of_irq_init(of_irq_ids);
47*4882a593Smuzhiyun}
48