linux-libre/Documentation/devicetree/bindings/arm/atmel-at91.txt

Atmel AT91 device tree bindings.
================================

Boards with a SoC of the Atmel AT91 or SMART family shall have the following
properties:

Required root node properties:
compatible: must be one of:
 * "atmel,at91rm9200"

 * "atmel,at91sam9" for SoCs using an ARM926EJ-S core, shall be extended with
   the specific SoC family or compatible:
    o "atmel,at91sam9260"
    o "atmel,at91sam9261"
    o "atmel,at91sam9263"
    o "atmel,at91sam9x5" for the 5 series, shall be extended with the specific
      SoC compatible:
       - "atmel,at91sam9g15"
       - "atmel,at91sam9g25"
       - "atmel,at91sam9g35"
       - "atmel,at91sam9x25"
       - "atmel,at91sam9x35"
    o "atmel,at91sam9g20"
    o "atmel,at91sam9g45"
    o "atmel,at91sam9n12"
    o "atmel,at91sam9rl"
    o "atmel,at91sam9xe"
 * "atmel,sama5" for SoCs using a Cortex-A5, shall be extended with the specific
   SoC family:
    o "atmel,sama5d2" shall be extended with the specific SoC compatible:
       - "atmel,sama5d27"
    o "atmel,sama5d3" shall be extended with the specific SoC compatible:
       - "atmel,sama5d31"
       - "atmel,sama5d33"
       - "atmel,sama5d34"
       - "atmel,sama5d35"
       - "atmel,sama5d36"
    o "atmel,sama5d4" shall be extended with the specific SoC compatible:
       - "atmel,sama5d41"
       - "atmel,sama5d42"
       - "atmel,sama5d43"
       - "atmel,sama5d44"

Chipid required properties:
- compatible: Should be "atmel,sama5d2-chipid"
- reg : Should contain registers location and length

PIT Timer required properties:
- compatible: Should be "atmel,at91sam9260-pit"
- reg: Should contain registers location and length
- interrupts: Should contain interrupt for the PIT which is the IRQ line
  shared across all System Controller members.

System Timer (ST) required properties:
- compatible: Should be "atmel,at91rm9200-st", "syscon", "simple-mfd"
- reg: Should contain registers location and length
- interrupts: Should contain interrupt for the ST which is the IRQ line
  shared across all System Controller members.
- clocks: phandle to input clock.
Its subnodes can be:
- watchdog: compatible should be "atmel,at91rm9200-wdt"

TC/TCLIB Timer required properties:
- compatible: Should be "atmel,<chip>-tcb".
  <chip> can be "at91rm9200" or "at91sam9x5"
- reg: Should contain registers location and length
- interrupts: Should contain all interrupts for the TC block
  Note that you can specify several interrupt cells if the TC
  block has one interrupt per channel.
- clock-names: tuple listing input clock names.
	Required elements: "t0_clk", "slow_clk"
	Optional elements: "t1_clk", "t2_clk"
- clocks: phandles to input clocks.

Examples:

One interrupt per TC block:
	tcb0: timer@fff7c000 {
		compatible = "atmel,at91rm9200-tcb";
		reg = <0xfff7c000 0x100>;
		interrupts = <18 4>;
		clocks = <&tcb0_clk>;
		clock-names = "t0_clk";
	};

One interrupt per TC channel in a TC block:
	tcb1: timer@fffdc000 {
		compatible = "atmel,at91rm9200-tcb";
		reg = <0xfffdc000 0x100>;
		interrupts = <26 4 27 4 28 4>;
		clocks = <&tcb1_clk>;
		clock-names = "t0_clk";
	};

RSTC Reset Controller required properties:
- compatible: Should be "atmel,<chip>-rstc".
  <chip> can be "at91sam9260" or "at91sam9g45" or "sama5d3"
- reg: Should contain registers location and length
- clocks: phandle to input clock.

Example:

	rstc@fffffd00 {
		compatible = "atmel,at91sam9260-rstc";
		reg = <0xfffffd00 0x10>;
		clocks = <&clk32k>;
	};

RAMC SDRAM/DDR Controller required properties:
- compatible: Should be "atmel,at91rm9200-sdramc", "syscon"
			"atmel,at91sam9260-sdramc",
			"atmel,at91sam9g45-ddramc",
			"atmel,sama5d3-ddramc",
- reg: Should contain registers location and length

Examples:

	ramc0: ramc@ffffe800 {
		compatible = "atmel,at91sam9g45-ddramc";
		reg = <0xffffe800 0x200>;
	};

SHDWC Shutdown Controller

required properties:
- compatible: Should be "atmel,<chip>-shdwc".
  <chip> can be "at91sam9260", "at91sam9rl" or "at91sam9x5".
- reg: Should contain registers location and length
- clocks: phandle to input clock.

optional properties:
- atmel,wakeup-mode: String, operation mode of the wakeup mode.
  Supported values are: "none", "high", "low", "any".
- atmel,wakeup-counter: Counter on Wake-up 0 (between 0x0 and 0xf).

optional at91sam9260 properties:
- atmel,wakeup-rtt-timer: boolean to enable Real-time Timer Wake-up.

optional at91sam9rl properties:
- atmel,wakeup-rtc-timer: boolean to enable Real-time Clock Wake-up.
- atmel,wakeup-rtt-timer: boolean to enable Real-time Timer Wake-up.

optional at91sam9x5 properties:
- atmel,wakeup-rtc-timer: boolean to enable Real-time Clock Wake-up.

Example:

	shdwc@fffffd10 {
		compatible = "atmel,at91sam9260-shdwc";
		reg = <0xfffffd10 0x10>;
		clocks = <&clk32k>;
	};

SHDWC SAMA5D2-Compatible Shutdown Controller

1) shdwc node

required properties:
- compatible: should be "atmel,sama5d2-shdwc".
- reg: should contain registers location and length
- clocks: phandle to input clock.
- #address-cells: should be one. The cell is the wake-up input index.
- #size-cells: should be zero.

optional properties:

- debounce-delay-us: minimum wake-up inputs debouncer period in
  microseconds. It's usually a board-related property.
- atmel,wakeup-rtc-timer: boolean to enable Real-Time Clock wake-up.

The node contains child nodes for each wake-up input that the platform uses.

2) input nodes

Wake-up input nodes are usually described in the "board" part of the Device
Tree. Note also that input 0 is linked to the wake-up pin and is frequently
used.

Required properties:
- reg: should contain the wake-up input index [0 - 15].

Optional properties:
- atmel,wakeup-active-high: boolean, the corresponding wake-up input described
  by the child, forces the wake-up of the core power supply on a high level.
  The default is to be active low.

Example:

On the SoC side:
	shdwc@f8048010 {
		compatible = "atmel,sama5d2-shdwc";
		reg = <0xf8048010 0x10>;
		clocks = <&clk32k>;
		#address-cells = <1>;
		#size-cells = <0>;
		atmel,wakeup-rtc-timer;
	};

On the board side:
	shdwc@f8048010 {
		debounce-delay-us = <976>;

		input@0 {
			reg = <0>;
		};

		input@1 {
			reg = <1>;
			atmel,wakeup-active-high;
		};
	};

Special Function Registers (SFR)

Special Function Registers (SFR) manage specific aspects of the integrated
memory, bridge implementations, processor and other functionality not controlled
elsewhere.

required properties:
- compatible: Should be "atmel,<chip>-sfr", "syscon".
  <chip> can be "sama5d3", "sama5d4" or "sama5d2".
- reg: Should contain registers location and length

	sfr@f0038000 {
		compatible = "atmel,sama5d3-sfr", "syscon";
		reg = <0xf0038000 0x60>;
	};