dt-bindings: watchdog: Consolidate SP805 binding docs

ARM AMBA Primecell SP805 Watchdog

SP805 WDT is a ARM Primecell Peripheral and has a standard-id register that

can be used to identify the peripheral type, vendor, and revision.

This value can be used for driver matching.

As SP805 WDT is a primecell IP, it follows the base bindings specified in

'arm/primecell.txt'

Required properties:

- compatible:  Should be "arm,sp805" & "arm,primecell"

- reg: Should contain location and length for watchdog timer register.

- interrupts: Should contain the list of watchdog timer interrupts.

- clocks: clocks driving the watchdog timer hardware. This list should be 2

	clocks. With 2 clocks, the order is wdogclk clock, apb_pclk.

- reg:         Should contain location and length for watchdog timer register

- clocks:      Clocks driving the watchdog timer hardware. This list should be

               2 clocks. With 2 clocks, the order is wdog_clk, apb_pclk

               wdog_clk can be equal to or be a sub-multiple of the apb_pclk

               frequency

- clock-names: Shall be "wdog_clk" for first clock and "apb_pclk" for the

               second one

Optional properties:

- interrupts:  Should specify WDT interrupt number

Example:

	watchdog@66090000 {

		compatible = "arm,sp805", "arm,primecell";

		reg = <0x66090000 0x1000>;

		interrupts = <GIC_SPI 406 IRQ_TYPE_LEVEL_HIGH>;

		clocks = <&apb_pclk>,<&apb_pclk>;

		clock-names = "wdogclk", "apb_pclk";

		clocks = <&wdt_clk>, <&apb_pclk>;

		clock-names = "wdog_clk", "apb_pclk";

	};

* ARM SP805 Watchdog Timer (WDT) Controller

SP805 WDT is a ARM Primecell Peripheral and has a standard-id register that

can be used to identify the peripheral type, vendor, and revision.

This value can be used for driver matching.

As SP805 WDT is a primecell IP, it follows the base bindings specified in

'arm/primecell.txt'

Required properties:

- compatible : Should be "arm,sp805-wdt", "arm,primecell"

- reg : Base address and size of the watchdog timer registers.

- clocks : From common clock binding.

           First clock is PCLK and the second is WDOGCLK.

           WDOGCLK can be equal to or be a sub-multiple of the PCLK frequency.

- clock-names : From common clock binding.

                Shall be "apb_pclk" for first clock and "wdog_clk" for the

                second one.

Optional properties:

- interrupts : Should specify WDT interrupt number.

Examples:

		cluster1_core0_watchdog: wdt@c000000 {

			compatible = "arm,sp805-wdt", "arm,primecell";

			reg = <0x0 0xc000000 0x0 0x1000>;

			clocks = <&clockgen 4 3>, <&clockgen 4 3>;

			clock-names = "apb_pclk", "wdog_clk";

		};