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Fabio Porceddabe49bba2012-11-12 09:37:25 +01001* Atmel Watchdog Timers
2
3** at91sam9-wdt
4
5Required properties:
6- compatible: must be "atmel,at91sam9260-wdt".
7- reg: physical base address of the controller and length of memory mapped
8 region.
Alexandre Bellonid79e3272015-07-30 00:43:07 +02009- clocks: phandle to input clock.
Fabio Porceddabe49bba2012-11-12 09:37:25 +010010
Fabio Porceddac1fd5f62013-02-14 09:14:25 +010011Optional properties:
12- timeout-sec: contains the watchdog timeout in seconds.
Boris BREZILLON6914c582013-10-04 09:24:13 +020013- interrupts : Should contain WDT interrupt.
14- atmel,max-heartbeat-sec : Should contain the maximum heartbeat value in
15 seconds. This value should be less or equal to 16. It is used to
16 compute the WDV field.
17- atmel,min-heartbeat-sec : Should contain the minimum heartbeat value in
18 seconds. This value must be smaller than the max-heartbeat-sec value.
19 It is used to compute the WDD field.
20- atmel,watchdog-type : Should be "hardware" or "software". Hardware watchdog
21 use the at91 watchdog reset. Software watchdog use the watchdog
22 interrupt to trigger a software reset.
23- atmel,reset-type : Should be "proc" or "all".
24 "all" : assert peripherals and processor reset signals
25 "proc" : assert the processor reset signal
26 This is valid only when using "hardware" watchdog.
27- atmel,disable : Should be present if you want to disable the watchdog.
28- atmel,idle-halt : Should be present if you want to stop the watchdog when
29 entering idle state.
Sylvain Rochet56608402015-01-18 14:26:50 +010030 CAUTION: This property should be used with care, it actually makes the
31 watchdog not counting when the CPU is in idle state, therefore the
32 watchdog reset time depends on mean CPU usage and will not reset at all
33 if the CPU stop working while it is in idle state, which is probably
34 not what you want.
Boris BREZILLON6914c582013-10-04 09:24:13 +020035- atmel,dbg-halt : Should be present if you want to stop the watchdog when
36 entering debug state.
Fabio Porceddac1fd5f62013-02-14 09:14:25 +010037
Fabio Porceddabe49bba2012-11-12 09:37:25 +010038Example:
Fabio Porceddabe49bba2012-11-12 09:37:25 +010039 watchdog@fffffd40 {
40 compatible = "atmel,at91sam9260-wdt";
41 reg = <0xfffffd40 0x10>;
Boris BREZILLON6914c582013-10-04 09:24:13 +020042 interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
Alexandre Bellonid79e3272015-07-30 00:43:07 +020043 clocks = <&clk32k>;
Boris BREZILLON6914c582013-10-04 09:24:13 +020044 timeout-sec = <15>;
45 atmel,watchdog-type = "hardware";
46 atmel,reset-type = "all";
47 atmel,dbg-halt;
48 atmel,idle-halt;
49 atmel,max-heartbeat-sec = <16>;
50 atmel,min-heartbeat-sec = <0>;
51 status = "okay";
Fabio Porceddabe49bba2012-11-12 09:37:25 +010052 };