68 lines
2.3 KiB
Text
68 lines
2.3 KiB
Text
|
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>;
|
||
|
...
|
||
|
};
|