Fabio Porcedda | be49bba | 2012-11-12 09:37:25 +0100 | [diff] [blame] | 1 | * Atmel Watchdog Timers |
| 2 | |
| 3 | ** at91sam9-wdt |
| 4 | |
| 5 | Required properties: |
| 6 | - compatible: must be "atmel,at91sam9260-wdt". |
| 7 | - reg: physical base address of the controller and length of memory mapped |
| 8 | region. |
Alexandre Belloni | d79e327 | 2015-07-30 00:43:07 +0200 | [diff] [blame] | 9 | - clocks: phandle to input clock. |
Fabio Porcedda | be49bba | 2012-11-12 09:37:25 +0100 | [diff] [blame] | 10 | |
Fabio Porcedda | c1fd5f6 | 2013-02-14 09:14:25 +0100 | [diff] [blame] | 11 | Optional properties: |
| 12 | - timeout-sec: contains the watchdog timeout in seconds. |
Boris BREZILLON | 6914c58 | 2013-10-04 09:24:13 +0200 | [diff] [blame] | 13 | - 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 Rochet | 5660840 | 2015-01-18 14:26:50 +0100 | [diff] [blame] | 30 | 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 BREZILLON | 6914c58 | 2013-10-04 09:24:13 +0200 | [diff] [blame] | 35 | - atmel,dbg-halt : Should be present if you want to stop the watchdog when |
| 36 | entering debug state. |
Fabio Porcedda | c1fd5f6 | 2013-02-14 09:14:25 +0100 | [diff] [blame] | 37 | |
Fabio Porcedda | be49bba | 2012-11-12 09:37:25 +0100 | [diff] [blame] | 38 | Example: |
Fabio Porcedda | be49bba | 2012-11-12 09:37:25 +0100 | [diff] [blame] | 39 | watchdog@fffffd40 { |
| 40 | compatible = "atmel,at91sam9260-wdt"; |
| 41 | reg = <0xfffffd40 0x10>; |
Boris BREZILLON | 6914c58 | 2013-10-04 09:24:13 +0200 | [diff] [blame] | 42 | interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>; |
Alexandre Belloni | d79e327 | 2015-07-30 00:43:07 +0200 | [diff] [blame] | 43 | clocks = <&clk32k>; |
Boris BREZILLON | 6914c58 | 2013-10-04 09:24:13 +0200 | [diff] [blame] | 44 | 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 Porcedda | be49bba | 2012-11-12 09:37:25 +0100 | [diff] [blame] | 52 | }; |