| b.liu | e958203 | 2025-04-17 19:18:16 +0800 | [diff] [blame] | 1 | MIPS CPU interrupt controller |
| 2 | |
| 3 | On MIPS the mips_cpu_irq_of_init() helper can be used to initialize the 8 CPU |
| 4 | IRQs from a devicetree file and create a irq_domain for IRQ controller. |
| 5 | |
| 6 | With the irq_domain in place we can describe how the 8 IRQs are wired to the |
| 7 | platforms internal interrupt controller cascade. |
| 8 | |
| 9 | Below is an example of a platform describing the cascade inside the devicetree |
| 10 | and the code used to load it inside arch_init_irq(). |
| 11 | |
| 12 | Required properties: |
| 13 | - compatible : Should be "mti,cpu-interrupt-controller" |
| 14 | |
| 15 | Example devicetree: |
| 16 | cpu-irq: cpu-irq { |
| 17 | #address-cells = <0>; |
| 18 | |
| 19 | interrupt-controller; |
| 20 | #interrupt-cells = <1>; |
| 21 | |
| 22 | compatible = "mti,cpu-interrupt-controller"; |
| 23 | }; |
| 24 | |
| 25 | intc: intc@200 { |
| 26 | compatible = "ralink,rt2880-intc"; |
| 27 | reg = <0x200 0x100>; |
| 28 | |
| 29 | interrupt-controller; |
| 30 | #interrupt-cells = <1>; |
| 31 | |
| 32 | interrupt-parent = <&cpu-irq>; |
| 33 | interrupts = <2>; |
| 34 | }; |
| 35 | |
| 36 | |
| 37 | Example platform irq.c: |
| 38 | static struct of_device_id __initdata of_irq_ids[] = { |
| 39 | { .compatible = "mti,cpu-interrupt-controller", .data = mips_cpu_irq_of_init }, |
| 40 | { .compatible = "ralink,rt2880-intc", .data = intc_of_init }, |
| 41 | {}, |
| 42 | }; |
| 43 | |
| 44 | void __init arch_init_irq(void) |
| 45 | { |
| 46 | of_irq_init(of_irq_ids); |
| 47 | } |