projects / mirror_ubuntu-bionic-kernel.git / blame
| Commit | Line | Data |
|---|---|---|
| be49bbae FP |
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. | |
| d79e327a | 9 | - clocks: phandle to input clock. |
| be49bbae | 10 | |
| c1fd5f64 FP |
11 | Optional properties: |
| 12 | - timeout-sec: contains the watchdog timeout in seconds. | |
| 6914c587 BB |
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. | |
| 56608400 SR |
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. | |
| 6914c587 BB |
35 | - atmel,dbg-halt : Should be present if you want to stop the watchdog when |
| 36 | entering debug state. | |
| c1fd5f64 | 37 | |
| be49bbae | 38 | Example: |
| be49bbae FP |
39 | watchdog@fffffd40 { |
| 40 | compatible = "atmel,at91sam9260-wdt"; | |
| 41 | reg = <0xfffffd40 0x10>; | |
| 6914c587 | 42 | interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>; |
| d79e327a | 43 | clocks = <&clk32k>; |
| 6914c587 BB |
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>; | |
| be49bbae | 51 | }; |