53 lines
2.0 KiB
Plaintext
53 lines
2.0 KiB
Plaintext
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* Atmel Watchdog Timers
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** at91sam9-wdt
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Required properties:
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- compatible: must be "atmel,at91sam9260-wdt".
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- reg: physical base address of the controller and length of memory mapped
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region.
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- clocks: phandle to input clock.
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Optional properties:
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- timeout-sec: contains the watchdog timeout in seconds.
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- interrupts : Should contain WDT interrupt.
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- atmel,max-heartbeat-sec : Should contain the maximum heartbeat value in
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seconds. This value should be less or equal to 16. It is used to
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compute the WDV field.
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- atmel,min-heartbeat-sec : Should contain the minimum heartbeat value in
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seconds. This value must be smaller than the max-heartbeat-sec value.
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It is used to compute the WDD field.
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- atmel,watchdog-type : Should be "hardware" or "software". Hardware watchdog
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use the at91 watchdog reset. Software watchdog use the watchdog
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interrupt to trigger a software reset.
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- atmel,reset-type : Should be "proc" or "all".
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"all" : assert peripherals and processor reset signals
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"proc" : assert the processor reset signal
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This is valid only when using "hardware" watchdog.
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- atmel,disable : Should be present if you want to disable the watchdog.
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- atmel,idle-halt : Should be present if you want to stop the watchdog when
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entering idle state.
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CAUTION: This property should be used with care, it actually makes the
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watchdog not counting when the CPU is in idle state, therefore the
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watchdog reset time depends on mean CPU usage and will not reset at all
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if the CPU stop working while it is in idle state, which is probably
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not what you want.
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- atmel,dbg-halt : Should be present if you want to stop the watchdog when
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entering debug state.
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Example:
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watchdog@fffffd40 {
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compatible = "atmel,at91sam9260-wdt";
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reg = <0xfffffd40 0x10>;
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interrupts = <1 IRQ_TYPE_LEVEL_HIGH 7>;
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clocks = <&clk32k>;
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timeout-sec = <15>;
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atmel,watchdog-type = "hardware";
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atmel,reset-type = "all";
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atmel,dbg-halt;
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atmel,idle-halt;
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atmel,max-heartbeat-sec = <16>;
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atmel,min-heartbeat-sec = <0>;
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status = "okay";
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};
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