linux/Documentation/devicetree/bindings/interrupt-controller/mips-gic.txt
Qais Yousef 16a8083ced irqchip/mips-gic: Add new DT property to reserve IPIs
The new property will allow to specify the range of GIC hwirqs to use for IPIs.

This is an optinal property. We preserve the previous behaviour of allocating
the last 2 * gic_vpes if it's not specified or DT is not supported.

Signed-off-by: Qais Yousef <qais.yousef@imgtec.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: <jason@lakedaemon.net>
Cc: <marc.zyngier@arm.com>
Cc: <jiang.liu@linux.intel.com>
Cc: <linux-mips@linux-mips.org>
Cc: <lisa.parratt@imgtec.com>
Cc: Qais Yousef <qsyousef@gmail.com>
Link: http://lkml.kernel.org/r/1449580830-23652-20-git-send-email-qais.yousef@imgtec.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2016-02-25 10:56:58 +01:00

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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>;
...
};