Documentation/devicetree/bindings/clock/at91-clock.txt - arm/linux-arm64-legacy - Git at Google

 Device Tree Clock bindings for arch-at91

 This binding uses the common clock binding[1].

 [1] Documentation/devicetree/bindings/clock/clock-bindings.txt

 Required properties:
 - compatible : shall be one of the following:
 	"atmel,at91sam9x5-sckc":
 		at91 SCKC (Slow Clock Controller)
 		This node contains the slow clock definitions.

 	"atmel,at91sam9x5-clk-slow-osc":
 		at91 slow oscillator

 	"atmel,at91sam9x5-clk-slow-rc-osc":
 		at91 internal slow RC oscillator

 	"atmel,at91rm9200-pmc" or
 	"atmel,at91sam9g45-pmc" or
 	"atmel,at91sam9n12-pmc" or
 	"atmel,at91sam9x5-pmc" or
 	"atmel,sama5d3-pmc":
 		at91 PMC (Power Management Controller)
 		All at91 specific clocks (clocks defined below) must be child
 		node of the PMC node.

 	"atmel,at91sam9x5-clk-slow" (under sckc node)
 	or
 	"atmel,at91sam9260-clk-slow" (under pmc node):
 		at91 slow clk

 	"atmel,at91rm9200-clk-main-osc"
 	"atmel,at91sam9x5-clk-main-rc-osc"
 		at91 main clk sources

 	"atmel,at91sam9x5-clk-main"
 	"atmel,at91rm9200-clk-main":
 		at91 main clock

 	"atmel,at91rm9200-clk-master" or
 	"atmel,at91sam9x5-clk-master":
 		at91 master clock

 	"atmel,at91sam9x5-clk-peripheral" or
 	"atmel,at91rm9200-clk-peripheral":
 		at91 peripheral clocks

 	"atmel,at91rm9200-clk-pll" or
 	"atmel,at91sam9g45-clk-pll" or
 	"atmel,at91sam9g20-clk-pllb" or
 	"atmel,sama5d3-clk-pll":
 		at91 pll clocks

 	"atmel,at91sam9x5-clk-plldiv":
 		at91 plla divisor

 	"atmel,at91rm9200-clk-programmable" or
 	"atmel,at91sam9g45-clk-programmable" or
 	"atmel,at91sam9x5-clk-programmable":
 		at91 programmable clocks

 	"atmel,at91sam9x5-clk-smd":
 		at91 SMD (Soft Modem) clock

 	"atmel,at91rm9200-clk-system":
 		at91 system clocks

 	"atmel,at91rm9200-clk-usb" or
 	"atmel,at91sam9x5-clk-usb" or
 	"atmel,at91sam9n12-clk-usb":
 		at91 usb clock

 	"atmel,at91sam9x5-clk-utmi":
 		at91 utmi clock

 Required properties for SCKC node:
 - reg : defines the IO memory reserved for the SCKC.
 - #size-cells : shall be 0 (reg is used to encode clk id).
 - #address-cells : shall be 1 (reg is used to encode clk id).


 For example:
 	sckc: sckc@fffffe50 {
 		compatible = "atmel,sama5d3-pmc";
 		reg = <0xfffffe50 0x4>
 		#size-cells = <0>;
 		#address-cells = <1>;

 		/* put at91 slow clocks here */
 	};


 Required properties for internal slow RC oscillator:
 - #clock-cells : from common clock binding; shall be set to 0.
 - clock-frequency : define the internal RC oscillator frequency.

 Optional properties:
 - clock-accuracy : define the internal RC oscillator accuracy.

 For example:
 	slow_rc_osc: slow_rc_osc {
 		compatible = "atmel,at91sam9x5-clk-slow-rc-osc";
 		clock-frequency = <32768>;
 		clock-accuracy = <50000000>;
 	};

 Required properties for slow oscillator:
 - #clock-cells : from common clock binding; shall be set to 0.
 - clocks : shall encode the main osc source clk sources (see atmel datasheet).

 Optional properties:
 - atmel,osc-bypass : boolean property. Set this when a clock signal is directly
   provided on XIN.

 For example:
 	slow_osc: slow_osc {
 		compatible = "atmel,at91rm9200-clk-slow-osc";
 		#clock-cells = <0>;
 		clocks = <&slow_xtal>;
 	};

 Required properties for slow clock:
 - #clock-cells : from common clock binding; shall be set to 0.
 - clocks : shall encode the slow clk sources (see atmel datasheet).

 For example:
 	clk32k: slck {
 		compatible = "atmel,at91sam9x5-clk-slow";
 		#clock-cells = <0>;
 		clocks = <&slow_rc_osc &slow_osc>;
 	};

 Required properties for PMC node:
 - reg : defines the IO memory reserved for the PMC.
 - #size-cells : shall be 0 (reg is used to encode clk id).
 - #address-cells : shall be 1 (reg is used to encode clk id).
 - interrupts : shall be set to PMC interrupt line.
 - interrupt-controller : tell that the PMC is an interrupt controller.
 - #interrupt-cells : must be set to 1. The first cell encodes the interrupt id,
 	and reflect the bit position in the PMC_ER/DR/SR registers.
 	You can use the dt macros defined in dt-bindings/clock/at91.h.
 	0 (AT91_PMC_MOSCS) -> main oscillator ready
 	1 (AT91_PMC_LOCKA) -> PLL A ready
 	2 (AT91_PMC_LOCKB) -> PLL B ready
 	3 (AT91_PMC_MCKRDY) -> master clock ready
 	6 (AT91_PMC_LOCKU) -> UTMI PLL clock ready
 	8 .. 15 (AT91_PMC_PCKRDY(id)) -> programmable clock ready
 	16 (AT91_PMC_MOSCSELS) -> main oscillator selected
 	17 (AT91_PMC_MOSCRCS) -> RC main oscillator stabilized
 	18 (AT91_PMC_CFDEV) -> clock failure detected

 For example:
 	pmc: pmc@fffffc00 {
 		compatible = "atmel,sama5d3-pmc";
 		interrupts = <1 4 7>;
 		interrupt-controller;
 		#interrupt-cells = <2>;
 		#size-cells = <0>;
 		#address-cells = <1>;

 		/* put at91 clocks here */
 	};

 Required properties for main clock internal RC oscillator:
 - interrupt-parent : must reference the PMC node.
 - interrupts : shall be set to "<0>".
 - clock-frequency : define the internal RC oscillator frequency.

 Optional properties:
 - clock-accuracy : define the internal RC oscillator accuracy.

 For example:
 	main_rc_osc: main_rc_osc {
 		compatible = "atmel,at91sam9x5-clk-main-rc-osc";
 		interrupt-parent = <&pmc>;
 		interrupts = <0>;
 		clock-frequency = <12000000>;
 		clock-accuracy = <50000000>;
 	};

 Required properties for main clock oscillator:
 - interrupt-parent : must reference the PMC node.
 - interrupts : shall be set to "<0>".
 - #clock-cells : from common clock binding; shall be set to 0.
 - clocks : shall encode the main osc source clk sources (see atmel datasheet).

 Optional properties:
 - atmel,osc-bypass : boolean property. Specified if a clock signal is provided
   on XIN.

   clock signal is directly provided on XIN pin.

 For example:
 	main_osc: main_osc {
 		compatible = "atmel,at91rm9200-clk-main-osc";
 		interrupt-parent = <&pmc>;
 		interrupts = <0>;
 		#clock-cells = <0>;
 		clocks = <&main_xtal>;
 	};

 Required properties for main clock:
 - interrupt-parent : must reference the PMC node.
 - interrupts : shall be set to "<0>".
 - #clock-cells : from common clock binding; shall be set to 0.
 - clocks : shall encode the main clk sources (see atmel datasheet).

 For example:
 	main: mainck {
 		compatible = "atmel,at91sam9x5-clk-main";
 		interrupt-parent = <&pmc>;
 		interrupts = <0>;
 		#clock-cells = <0>;
 		clocks = <&main_rc_osc &main_osc>;
 	};

 Required properties for master clock:
 - interrupt-parent : must reference the PMC node.
 - interrupts : shall be set to "<3>".
 - #clock-cells : from common clock binding; shall be set to 0.
 - clocks : shall be the master clock sources (see atmel datasheet) phandles.
 	e.g. "<&ck32k>, <&main>, <&plla>, <&pllb>".
 - atmel,clk-output-range : minimum and maximum clock frequency (two u32
 			   fields).
 	   e.g. output = <0 133000000>; <=> 0 to 133MHz.
 - atmel,clk-divisors : master clock divisors table (four u32 fields).
 		0 <=> reserved value.
 		e.g. divisors = <1 2 4 6>;
 - atmel,master-clk-have-div3-pres : some SoC use the reserved value 7 in the
 				    PRES field as CLOCK_DIV3 (e.g sam9x5).

 For example:
 	mck: mck {
 		compatible = "atmel,at91rm9200-clk-master";
 		interrupt-parent = <&pmc>;
 		interrupts = <3>;
 		#clock-cells = <0>;
 		atmel,clk-output-range = <0 133000000>;
 		atmel,clk-divisors = <1 2 4 0>;
 	};

 Required properties for peripheral clocks:
 - #size-cells : shall be 0 (reg is used to encode clk id).
 - #address-cells : shall be 1 (reg is used to encode clk id).
 - clocks : shall be the master clock phandle.
 	e.g. clocks = <&mck>;
 - name: device tree node describing a specific system clock.
 	* #clock-cells : from common clock binding; shall be set to 0.
 	* reg: peripheral id. See Atmel's datasheets to get a full
 	  list of peripheral ids.
 	* atmel,clk-output-range : minimum and maximum clock frequency
 	  (two u32 fields). Only valid on at91sam9x5-clk-peripheral
 	  compatible IPs.

 For example:
 	periph: periphck {
 		compatible = "atmel,at91sam9x5-clk-peripheral";
 		#size-cells = <0>;
 		#address-cells = <1>;
 		clocks = <&mck>;

 		ssc0_clk {
 			#clock-cells = <0>;
 			reg = <2>;
 			atmel,clk-output-range = <0 133000000>;
 		};

 		usart0_clk {
 			#clock-cells = <0>;
 			reg = <3>;
 			atmel,clk-output-range = <0 66000000>;
 		};
 	};


 Required properties for pll clocks:
 - interrupt-parent : must reference the PMC node.
 - interrupts : shall be set to "<1>".
 - #clock-cells : from common clock binding; shall be set to 0.
 - clocks : shall be the main clock phandle.
 - reg : pll id.
 	0 -> PLL A
 	1 -> PLL B
 - atmel,clk-input-range : minimum and maximum source clock frequency (two u32
 			  fields).
 	  e.g. input = <1 32000000>; <=> 1 to 32MHz.
 - #atmel,pll-clk-output-range-cells : number of cells reserved for pll output
 				      range description. Sould be set to 2, 3
 				      or 4.
 	* 1st and 2nd cells represent the frequency range (min-max).
 	* 3rd cell is optional and represents the OUT field value for the given
 	  range.
 	* 4th cell is optional and represents the ICPLL field (PLLICPR
 	  register)
 - atmel,pll-clk-output-ranges : pll output frequency ranges + optional parameter
 				depending on #atmel,pll-output-range-cells
 				property value.

 For example:
 	plla: pllack {
 		compatible = "atmel,at91sam9g45-clk-pll";
 		interrupt-parent = <&pmc>;
 		interrupts = <1>;
 		#clock-cells = <0>;
 		clocks = <&main>;
 		reg = <0>;
 		atmel,clk-input-range = <2000000 32000000>;
 		#atmel,pll-clk-output-range-cells = <4>;
 		atmel,pll-clk-output-ranges = <74500000 800000000 0 0
 					       69500000 750000000 1 0
 					       64500000 700000000 2 0
 					       59500000 650000000 3 0
 					       54500000 600000000 0 1
 					       49500000 550000000 1 1
 					       44500000 500000000 2 1
 					       40000000 450000000 3 1>;
 	};

 Required properties for plldiv clocks (plldiv = pll / 2):
 - #clock-cells : from common clock binding; shall be set to 0.
 - clocks : shall be the plla clock phandle.

 The pll divisor is equal to 2 and cannot be changed.

 For example:
 	plladiv: plladivck {
 		compatible = "atmel,at91sam9x5-clk-plldiv";
 		#clock-cells = <0>;
 		clocks = <&plla>;
 	};

 Required properties for programmable clocks:
 - interrupt-parent : must reference the PMC node.
 - #size-cells : shall be 0 (reg is used to encode clk id).
 - #address-cells : shall be 1 (reg is used to encode clk id).
 - clocks : shall be the programmable clock source phandles.
 	e.g. clocks = <&clk32k>, <&main>, <&plla>, <&pllb>;
 - name: device tree node describing a specific prog clock.
 	* #clock-cells : from common clock binding; shall be set to 0.
 	* reg : programmable clock id (register offset from  PCKx
 			 register).
 	* interrupts : shall be set to "<(8 + id)>".

 For example:
 	prog: progck {
 		compatible = "atmel,at91sam9g45-clk-programmable";
 		#size-cells = <0>;
 		#address-cells = <1>;
 		interrupt-parent = <&pmc>;
 		clocks = <&clk32k>, <&main>, <&plladiv>, <&utmi>, <&mck>;

 		prog0 {
 			#clock-cells = <0>;
 			reg = <0>;
 			interrupts = <8>;
 		};

 		prog1 {
 			#clock-cells = <0>;
 			reg = <1>;
 			interrupts = <9>;
 		};
 	};


 Required properties for smd clock:
 - #clock-cells : from common clock binding; shall be set to 0.
 - clocks : shall be the smd clock source phandles.
 	e.g. clocks = <&plladiv>, <&utmi>;

 For example:
 	smd: smdck {
 		compatible = "atmel,at91sam9x5-clk-smd";
 		#clock-cells = <0>;
 		clocks = <&plladiv>, <&utmi>;
 	};

 Required properties for system clocks:
 - #size-cells : shall be 0 (reg is used to encode clk id).
 - #address-cells : shall be 1 (reg is used to encode clk id).
 - name: device tree node describing a specific system clock.
 	* #clock-cells : from common clock binding; shall be set to 0.
 	* reg: system clock id (bit position in SCER/SCDR/SCSR registers).
 	      See Atmel's datasheet to get a full list of system clock ids.

 For example:
 	system: systemck {
 		compatible = "atmel,at91rm9200-clk-system";
 		#address-cells = <1>;
 		#size-cells = <0>;

 		ddrck {
 			#clock-cells = <0>;
 			reg = <2>;
 			clocks = <&mck>;
 		};

 		uhpck {
 			#clock-cells = <0>;
 			reg = <6>;
 			clocks = <&usb>;
 		};

 		udpck {
 			#clock-cells = <0>;
 			reg = <7>;
 			clocks = <&usb>;
 		};
 	};


 Required properties for usb clock:
 - #clock-cells : from common clock binding; shall be set to 0.
 - clocks : shall be the smd clock source phandles.
 	e.g. clocks = <&pllb>;
 - atmel,clk-divisors (only available for "atmel,at91rm9200-clk-usb"):
 	usb clock divisor table.
 	e.g. divisors = <1 2 4 0>;

 For example:
 	usb: usbck {
 		compatible = "atmel,at91sam9x5-clk-usb";
 		#clock-cells = <0>;
 		clocks = <&plladiv>, <&utmi>;
 	};

 	usb: usbck {
 		compatible = "atmel,at91rm9200-clk-usb";
 		#clock-cells = <0>;
 		clocks = <&pllb>;
 		atmel,clk-divisors = <1 2 4 0>;
 	};


 Required properties for utmi clock:
 - interrupt-parent : must reference the PMC node.
 - interrupts : shall be set to "<AT91_PMC_LOCKU IRQ_TYPE_LEVEL_HIGH>".
 - #clock-cells : from common clock binding; shall be set to 0.
 - clocks : shall be the main clock source phandle.

 For example:
 	utmi: utmick {
 		compatible = "atmel,at91sam9x5-clk-utmi";
 		interrupt-parent = <&pmc>;
 		interrupts = <AT91_PMC_LOCKU IRQ_TYPE_LEVEL_HIGH>;
 		#clock-cells = <0>;
 		clocks = <&main>;
 	};
	Device Tree Clock bindings for arch-at91

	This binding uses the common clock binding[1].

	[1] Documentation/devicetree/bindings/clock/clock-bindings.txt

	Required properties:
	- compatible : shall be one of the following:
	"atmel,at91sam9x5-sckc":
	at91 SCKC (Slow Clock Controller)
	This node contains the slow clock definitions.

	"atmel,at91sam9x5-clk-slow-osc":
	at91 slow oscillator

	"atmel,at91sam9x5-clk-slow-rc-osc":
	at91 internal slow RC oscillator

	"atmel,at91rm9200-pmc" or
	"atmel,at91sam9g45-pmc" or
	"atmel,at91sam9n12-pmc" or
	"atmel,at91sam9x5-pmc" or
	"atmel,sama5d3-pmc":
	at91 PMC (Power Management Controller)
	All at91 specific clocks (clocks defined below) must be child
	node of the PMC node.

	"atmel,at91sam9x5-clk-slow" (under sckc node)
	or
	"atmel,at91sam9260-clk-slow" (under pmc node):
	at91 slow clk

	"atmel,at91rm9200-clk-main-osc"
	"atmel,at91sam9x5-clk-main-rc-osc"
	at91 main clk sources

	"atmel,at91sam9x5-clk-main"
	"atmel,at91rm9200-clk-main":
	at91 main clock

	"atmel,at91rm9200-clk-master" or
	"atmel,at91sam9x5-clk-master":
	at91 master clock

	"atmel,at91sam9x5-clk-peripheral" or
	"atmel,at91rm9200-clk-peripheral":
	at91 peripheral clocks

	"atmel,at91rm9200-clk-pll" or
	"atmel,at91sam9g45-clk-pll" or
	"atmel,at91sam9g20-clk-pllb" or
	"atmel,sama5d3-clk-pll":
	at91 pll clocks

	"atmel,at91sam9x5-clk-plldiv":
	at91 plla divisor

	"atmel,at91rm9200-clk-programmable" or
	"atmel,at91sam9g45-clk-programmable" or
	"atmel,at91sam9x5-clk-programmable":
	at91 programmable clocks

	"atmel,at91sam9x5-clk-smd":
	at91 SMD (Soft Modem) clock

	"atmel,at91rm9200-clk-system":
	at91 system clocks

	"atmel,at91rm9200-clk-usb" or
	"atmel,at91sam9x5-clk-usb" or
	"atmel,at91sam9n12-clk-usb":
	at91 usb clock

	"atmel,at91sam9x5-clk-utmi":
	at91 utmi clock

	Required properties for SCKC node:
	- reg : defines the IO memory reserved for the SCKC.
	- #size-cells : shall be 0 (reg is used to encode clk id).
	- #address-cells : shall be 1 (reg is used to encode clk id).


	For example:
	sckc: sckc@fffffe50 {
	compatible = "atmel,sama5d3-pmc";
	reg = <0xfffffe50 0x4>
	#size-cells = <0>;
	#address-cells = <1>;

	/* put at91 slow clocks here */
	};


	Required properties for internal slow RC oscillator:
	- #clock-cells : from common clock binding; shall be set to 0.
	- clock-frequency : define the internal RC oscillator frequency.

	Optional properties:
	- clock-accuracy : define the internal RC oscillator accuracy.

	For example:
	slow_rc_osc: slow_rc_osc {
	compatible = "atmel,at91sam9x5-clk-slow-rc-osc";
	clock-frequency = <32768>;
	clock-accuracy = <50000000>;
	};

	Required properties for slow oscillator:
	- #clock-cells : from common clock binding; shall be set to 0.
	- clocks : shall encode the main osc source clk sources (see atmel datasheet).

	Optional properties:
	- atmel,osc-bypass : boolean property. Set this when a clock signal is directly
	provided on XIN.

	For example:
	slow_osc: slow_osc {
	compatible = "atmel,at91rm9200-clk-slow-osc";
	#clock-cells = <0>;
	clocks = <&slow_xtal>;
	};

	Required properties for slow clock:
	- #clock-cells : from common clock binding; shall be set to 0.
	- clocks : shall encode the slow clk sources (see atmel datasheet).

	For example:
	clk32k: slck {
	compatible = "atmel,at91sam9x5-clk-slow";
	#clock-cells = <0>;
	clocks = <&slow_rc_osc &slow_osc>;
	};

	Required properties for PMC node:
	- reg : defines the IO memory reserved for the PMC.
	- #size-cells : shall be 0 (reg is used to encode clk id).
	- #address-cells : shall be 1 (reg is used to encode clk id).
	- interrupts : shall be set to PMC interrupt line.
	- interrupt-controller : tell that the PMC is an interrupt controller.
	- #interrupt-cells : must be set to 1. The first cell encodes the interrupt id,
	and reflect the bit position in the PMC_ER/DR/SR registers.
	You can use the dt macros defined in dt-bindings/clock/at91.h.
	0 (AT91_PMC_MOSCS) -> main oscillator ready
	1 (AT91_PMC_LOCKA) -> PLL A ready
	2 (AT91_PMC_LOCKB) -> PLL B ready
	3 (AT91_PMC_MCKRDY) -> master clock ready
	6 (AT91_PMC_LOCKU) -> UTMI PLL clock ready
	8 .. 15 (AT91_PMC_PCKRDY(id)) -> programmable clock ready
	16 (AT91_PMC_MOSCSELS) -> main oscillator selected
	17 (AT91_PMC_MOSCRCS) -> RC main oscillator stabilized
	18 (AT91_PMC_CFDEV) -> clock failure detected

	For example:
	pmc: pmc@fffffc00 {
	compatible = "atmel,sama5d3-pmc";
	interrupts = <1 4 7>;
	interrupt-controller;
	#interrupt-cells = <2>;
	#size-cells = <0>;
	#address-cells = <1>;

	/* put at91 clocks here */
	};

	Required properties for main clock internal RC oscillator:
	- interrupt-parent : must reference the PMC node.
	- interrupts : shall be set to "<0>".
	- clock-frequency : define the internal RC oscillator frequency.

	Optional properties:
	- clock-accuracy : define the internal RC oscillator accuracy.

	For example:
	main_rc_osc: main_rc_osc {
	compatible = "atmel,at91sam9x5-clk-main-rc-osc";
	interrupt-parent = <&pmc>;
	interrupts = <0>;
	clock-frequency = <12000000>;
	clock-accuracy = <50000000>;
	};

	Required properties for main clock oscillator:
	- interrupt-parent : must reference the PMC node.
	- interrupts : shall be set to "<0>".
	- #clock-cells : from common clock binding; shall be set to 0.
	- clocks : shall encode the main osc source clk sources (see atmel datasheet).

	Optional properties:
	- atmel,osc-bypass : boolean property. Specified if a clock signal is provided
	on XIN.

	clock signal is directly provided on XIN pin.

	For example:
	main_osc: main_osc {
	compatible = "atmel,at91rm9200-clk-main-osc";
	interrupt-parent = <&pmc>;
	interrupts = <0>;
	#clock-cells = <0>;
	clocks = <&main_xtal>;
	};

	Required properties for main clock:
	- interrupt-parent : must reference the PMC node.
	- interrupts : shall be set to "<0>".
	- #clock-cells : from common clock binding; shall be set to 0.
	- clocks : shall encode the main clk sources (see atmel datasheet).

	For example:
	main: mainck {
	compatible = "atmel,at91sam9x5-clk-main";
	interrupt-parent = <&pmc>;
	interrupts = <0>;
	#clock-cells = <0>;
	clocks = <&main_rc_osc &main_osc>;
	};

	Required properties for master clock:
	- interrupt-parent : must reference the PMC node.
	- interrupts : shall be set to "<3>".
	- #clock-cells : from common clock binding; shall be set to 0.
	- clocks : shall be the master clock sources (see atmel datasheet) phandles.
	e.g. "<&ck32k>, <&main>, <&plla>, <&pllb>".
	- atmel,clk-output-range : minimum and maximum clock frequency (two u32
	fields).
	e.g. output = <0 133000000>; <=> 0 to 133MHz.
	- atmel,clk-divisors : master clock divisors table (four u32 fields).
	0 <=> reserved value.
	e.g. divisors = <1 2 4 6>;
	- atmel,master-clk-have-div3-pres : some SoC use the reserved value 7 in the
	PRES field as CLOCK_DIV3 (e.g sam9x5).

	For example:
	mck: mck {
	compatible = "atmel,at91rm9200-clk-master";
	interrupt-parent = <&pmc>;
	interrupts = <3>;
	#clock-cells = <0>;
	atmel,clk-output-range = <0 133000000>;
	atmel,clk-divisors = <1 2 4 0>;
	};

	Required properties for peripheral clocks:
	- #size-cells : shall be 0 (reg is used to encode clk id).
	- #address-cells : shall be 1 (reg is used to encode clk id).
	- clocks : shall be the master clock phandle.
	e.g. clocks = <&mck>;
	- name: device tree node describing a specific system clock.
	* #clock-cells : from common clock binding; shall be set to 0.
	* reg: peripheral id. See Atmel's datasheets to get a full
	list of peripheral ids.
	* atmel,clk-output-range : minimum and maximum clock frequency
	(two u32 fields). Only valid on at91sam9x5-clk-peripheral
	compatible IPs.

	For example:
	periph: periphck {
	compatible = "atmel,at91sam9x5-clk-peripheral";
	#size-cells = <0>;
	#address-cells = <1>;
	clocks = <&mck>;

	ssc0_clk {
	#clock-cells = <0>;
	reg = <2>;
	atmel,clk-output-range = <0 133000000>;
	};

	usart0_clk {
	#clock-cells = <0>;
	reg = <3>;
	atmel,clk-output-range = <0 66000000>;
	};
	};


	Required properties for pll clocks:
	- interrupt-parent : must reference the PMC node.
	- interrupts : shall be set to "<1>".
	- #clock-cells : from common clock binding; shall be set to 0.
	- clocks : shall be the main clock phandle.
	- reg : pll id.
	0 -> PLL A
	1 -> PLL B
	- atmel,clk-input-range : minimum and maximum source clock frequency (two u32
	fields).
	e.g. input = <1 32000000>; <=> 1 to 32MHz.
	- #atmel,pll-clk-output-range-cells : number of cells reserved for pll output
	range description. Sould be set to 2, 3
	or 4.
	* 1st and 2nd cells represent the frequency range (min-max).
	* 3rd cell is optional and represents the OUT field value for the given
	range.
	* 4th cell is optional and represents the ICPLL field (PLLICPR
	register)
	- atmel,pll-clk-output-ranges : pll output frequency ranges + optional parameter
	depending on #atmel,pll-output-range-cells
	property value.

	For example:
	plla: pllack {
	compatible = "atmel,at91sam9g45-clk-pll";
	interrupt-parent = <&pmc>;
	interrupts = <1>;
	#clock-cells = <0>;
	clocks = <&main>;
	reg = <0>;
	atmel,clk-input-range = <2000000 32000000>;
	#atmel,pll-clk-output-range-cells = <4>;
	atmel,pll-clk-output-ranges = <74500000 800000000 0 0
	69500000 750000000 1 0
	64500000 700000000 2 0
	59500000 650000000 3 0
	54500000 600000000 0 1
	49500000 550000000 1 1
	44500000 500000000 2 1
	40000000 450000000 3 1>;
	};

	Required properties for plldiv clocks (plldiv = pll / 2):
	- #clock-cells : from common clock binding; shall be set to 0.
	- clocks : shall be the plla clock phandle.

	The pll divisor is equal to 2 and cannot be changed.

	For example:
	plladiv: plladivck {
	compatible = "atmel,at91sam9x5-clk-plldiv";
	#clock-cells = <0>;
	clocks = <&plla>;
	};

	Required properties for programmable clocks:
	- interrupt-parent : must reference the PMC node.
	- #size-cells : shall be 0 (reg is used to encode clk id).
	- #address-cells : shall be 1 (reg is used to encode clk id).
	- clocks : shall be the programmable clock source phandles.
	e.g. clocks = <&clk32k>, <&main>, <&plla>, <&pllb>;
	- name: device tree node describing a specific prog clock.
	* #clock-cells : from common clock binding; shall be set to 0.
	* reg : programmable clock id (register offset from PCKx
	register).
	* interrupts : shall be set to "<(8 + id)>".

	For example:
	prog: progck {
	compatible = "atmel,at91sam9g45-clk-programmable";
	#size-cells = <0>;
	#address-cells = <1>;
	interrupt-parent = <&pmc>;
	clocks = <&clk32k>, <&main>, <&plladiv>, <&utmi>, <&mck>;

	prog0 {
	#clock-cells = <0>;
	reg = <0>;
	interrupts = <8>;
	};

	prog1 {
	#clock-cells = <0>;
	reg = <1>;
	interrupts = <9>;
	};
	};


	Required properties for smd clock:
	- #clock-cells : from common clock binding; shall be set to 0.
	- clocks : shall be the smd clock source phandles.
	e.g. clocks = <&plladiv>, <&utmi>;

	For example:
	smd: smdck {
	compatible = "atmel,at91sam9x5-clk-smd";
	#clock-cells = <0>;
	clocks = <&plladiv>, <&utmi>;
	};

	Required properties for system clocks:
	- #size-cells : shall be 0 (reg is used to encode clk id).
	- #address-cells : shall be 1 (reg is used to encode clk id).
	- name: device tree node describing a specific system clock.
	* #clock-cells : from common clock binding; shall be set to 0.
	* reg: system clock id (bit position in SCER/SCDR/SCSR registers).
	See Atmel's datasheet to get a full list of system clock ids.

	For example:
	system: systemck {
	compatible = "atmel,at91rm9200-clk-system";
	#address-cells = <1>;
	#size-cells = <0>;

	ddrck {
	#clock-cells = <0>;
	reg = <2>;
	clocks = <&mck>;
	};

	uhpck {
	#clock-cells = <0>;
	reg = <6>;
	clocks = <&usb>;
	};

	udpck {
	#clock-cells = <0>;
	reg = <7>;
	clocks = <&usb>;
	};
	};


	Required properties for usb clock:
	- #clock-cells : from common clock binding; shall be set to 0.
	- clocks : shall be the smd clock source phandles.
	e.g. clocks = <&pllb>;
	- atmel,clk-divisors (only available for "atmel,at91rm9200-clk-usb"):
	usb clock divisor table.
	e.g. divisors = <1 2 4 0>;

	For example:
	usb: usbck {
	compatible = "atmel,at91sam9x5-clk-usb";
	#clock-cells = <0>;
	clocks = <&plladiv>, <&utmi>;
	};

	usb: usbck {
	compatible = "atmel,at91rm9200-clk-usb";
	#clock-cells = <0>;
	clocks = <&pllb>;
	atmel,clk-divisors = <1 2 4 0>;
	};


	Required properties for utmi clock:
	- interrupt-parent : must reference the PMC node.
	- interrupts : shall be set to "<AT91_PMC_LOCKU IRQ_TYPE_LEVEL_HIGH>".
	- #clock-cells : from common clock binding; shall be set to 0.
	- clocks : shall be the main clock source phandle.

	For example:
	utmi: utmick {
	compatible = "atmel,at91sam9x5-clk-utmi";
	interrupt-parent = <&pmc>;
	interrupts = <AT91_PMC_LOCKU IRQ_TYPE_LEVEL_HIGH>;
	#clock-cells = <0>;
	clocks = <&main>;
	};