linux/Documentation/devicetree/bindings/interrupt-controller/mips-gic.txt

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MIPS Global Interrupt Controller (GIC)
The MIPS GIC routes external interrupts to individual VPEs and IRQ pins.
It also supports local (per-processor) interrupts and software-generated
interrupts which can be used as IPIs. The GIC also includes a free-running
global timer, per-CPU count/compare timers, and a watchdog.
Required properties:
- compatible : Should be "mti,gic".
- interrupt-controller : Identifies the node as an interrupt controller
- #interrupt-cells : Specifies the number of cells needed to encode an
interrupt specifier. Should be 3.
- The first cell is the type of interrupt, local or shared.
See <include/dt-bindings/interrupt-controller/mips-gic.h>.
- The second cell is the GIC interrupt number.
- The third cell encodes the interrupt flags.
See <include/dt-bindings/interrupt-controller/irq.h> for a list of valid
flags.
Optional properties:
- reg : Base address and length of the GIC registers. If not present,
the base address reported by the hardware GCR_GIC_BASE will be used.
- mti,reserved-cpu-vectors : Specifies the list of CPU interrupt vectors
to which the GIC may not route interrupts. Valid values are 2 - 7.
This property is ignored if the CPU is started in EIC mode.
- mti,reserved-ipi-vectors : Specifies the range of GIC interrupts that are
reserved for IPIs.
It accepts 2 values, the 1st is the starting interrupt and the 2nd is the size
of the reserved range.
If not specified, the driver will allocate the last 2 * number of VPEs in the
system.
Required properties for timer sub-node:
- compatible : Should be "mti,gic-timer".
- interrupts : Interrupt for the GIC local timer.
Optional properties for timer sub-node:
- clocks : GIC timer operating clock.
- clock-frequency : Clock frequency at which the GIC timers operate.
Note that one of clocks or clock-frequency must be specified.
Example:
gic: interrupt-controller@1bdc0000 {
compatible = "mti,gic";
reg = <0x1bdc0000 0x20000>;
interrupt-controller;
#interrupt-cells = <3>;
mti,reserved-cpu-vectors = <7>;
mti,reserved-ipi-vectors = <40 8>;
timer {
compatible = "mti,gic-timer";
interrupts = <GIC_LOCAL 1 IRQ_TYPE_NONE>;
clock-frequency = <50000000>;
};
};
uart@18101400 {
...
interrupt-parent = <&gic>;
interrupts = <GIC_SHARED 24 IRQ_TYPE_LEVEL_HIGH>;
...
};