[PATCHv2 1/2] dts: Documentation: AT91 Watchdog, explain what atmel,idle-halt property really do
From: Boris Brezillon <hidden>
Date: 2015-01-22 18:14:03
Also in:
linux-devicetree
On Sun, 18 Jan 2015 14:26:50 +0100 Sylvain Rochet [off-list ref] wrote:
atmel,idle-halt property should be used with care, it actually makes the watchdog not counting when the CPU is in idle state, therefore the watchdog reset time depends on mean CPU usage and will not reset at all of the CPU stop working while it is in idle state, which is probably not what you want. Signed-off-by: Sylvain Rochet <redacted>
Acked-by: Boris Brezillon <redacted>
quoted hunk
--- Documentation/devicetree/bindings/watchdog/atmel-wdt.txt | 5 +++++ 1 file changed, 5 insertions(+)diff --git a/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt b/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt index f90e294..a4d8697 100644 --- a/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt +++ b/Documentation/devicetree/bindings/watchdog/atmel-wdt.txt@@ -26,6 +26,11 @@ Optional properties: - atmel,disable : Should be present if you want to disable the watchdog. - atmel,idle-halt : Should be present if you want to stop the watchdog when entering idle state. + CAUTION: This property should be used with care, it actually makes the + watchdog not counting when the CPU is in idle state, therefore the + watchdog reset time depends on mean CPU usage and will not reset at all + if the CPU stop working while it is in idle state, which is probably + not what you want. - atmel,dbg-halt : Should be present if you want to stop the watchdog when entering debug state.
-- Boris Brezillon, Free Electrons Embedded Linux and Kernel engineering http://free-electrons.com