summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
-rw-r--r--Documentation/devicetree/bindings/mips/cpu_irq.txt47
1 files changed, 47 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/mips/cpu_irq.txt b/Documentation/devicetree/bindings/mips/cpu_irq.txt
new file mode 100644
index 000000000000..13aa4b62c62a
--- /dev/null
+++ b/Documentation/devicetree/bindings/mips/cpu_irq.txt
@@ -0,0 +1,47 @@
+MIPS CPU interrupt controller
+
+On MIPS the mips_cpu_intc_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_intc_init },
+ { .compatible = "ralink,rt2880-intc", .data = intc_of_init },
+ {},
+};
+
+void __init arch_init_irq(void)
+{
+ of_irq_init(of_irq_ids);
+}
OpenPOWER on IntegriCloud