| MIPS CPU interrupt controller |
| |
| On MIPS the mips_cpu_irq_of_init() helper can be used to initialize the 8 CPU |
| IRQs from a devicetree file and create a irq_domain for IRQ controller. |
| |
| With the irq_domain in place we can describe how the 8 IRQs are wired to the |
| platforms internal interrupt controller cascade. |
| |
| Below is an example of a platform describing the cascade inside the devicetree |
| and the code used to load it inside arch_init_irq(). |
| |
| Required properties: |
| - compatible : Should be "mti,cpu-interrupt-controller" |
| |
| Example devicetree: |
| cpu-irq: cpu-irq@0 { |
| #address-cells = <0>; |
| |
| interrupt-controller; |
| #interrupt-cells = <1>; |
| |
| compatible = "mti,cpu-interrupt-controller"; |
| }; |
| |
| intc: intc@200 { |
| compatible = "ralink,rt2880-intc"; |
| reg = <0x200 0x100>; |
| |
| interrupt-controller; |
| #interrupt-cells = <1>; |
| |
| interrupt-parent = <&cpu-irq>; |
| interrupts = <2>; |
| }; |
| |
| |
| Example platform irq.c: |
| static struct of_device_id __initdata of_irq_ids[] = { |
| { .compatible = "mti,cpu-interrupt-controller", .data = mips_cpu_irq_of_init }, |
| { .compatible = "ralink,rt2880-intc", .data = intc_of_init }, |
| {}, |
| }; |
| |
| void __init arch_init_irq(void) |
| { |
| of_irq_init(of_irq_ids); |
| } |