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* ARM Timer Watchdog

ARM 11MP, Cortex-A5 and Cortex-A9 are often associated with a per-core
Timer-Watchdog (aka TWD), which provides both a per-cpu local timer
and watchdog.

The TWD is usually attached to a GIC to deliver its two per-processor
interrupts.

** Timer node required properties:

- compatible : Should be one of:
	"arm,cortex-a9-twd-timer"
	"arm,cortex-a5-twd-timer"
	"arm,arm11mp-twd-timer"

- interrupts : One interrupt to each core

- reg : Specify the base address and the size of the TWD timer
	register window.

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Optional

- always-on : a boolean property. If present, the timer is powered through
  an always-on power domain, therefore it never loses context.

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Example:

	twd-timer@2c000600 {
		compatible = "arm,arm11mp-twd-timer"";
		reg = <0x2c000600 0x20>;
		interrupts = <1 13 0xf01>;
	};

** Watchdog node properties:

- compatible : Should be one of:
	"arm,cortex-a9-twd-wdt"
	"arm,cortex-a5-twd-wdt"
	"arm,arm11mp-twd-wdt"

- interrupts : One interrupt to each core

- reg : Specify the base address and the size of the TWD watchdog
	register window.

Example:

	twd-watchdog@2c000620 {
		compatible = "arm,arm11mp-twd-wdt";
		reg = <0x2c000620 0x20>;
		interrupts = <1 14 0xf01>;
	};