lkml.org 
[lkml]   [2014]   [Sep]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v2] watchdog: omap_wdt: Add 'early_disable' module parameter
From
Date
On Čt, 2014-09-18 at 21:12 -0700, Guenter Roeck wrote:
> How about reading the OMAP_WATCHDOG_SPR register ?

Unfortunately this would be not only extremely fragile (someone writes
correct start sequence followed by some garbage -- WD is running and we
are reading garbage) but according to some experiments seems not to work
at all (I am reading "0" even for a running WD probably as a result to
the pm_runtime_get_sync() call).

One of the TI employees on the TI forum confirmed (I know this is not a
rock-solid information) that it is not possible to safely determine if
the WD is running or not.


> Either case, you can not issue a message about the watchdog being
> stopped or started if you don't know if it was actually stopped
> or started. Also, if you don't really know if the watchdog was
> stopped or started, all you can do is to either stop or start it,
> without judgment about its previous condition.

You are right. I was blinded by our use case where the watchdog is
always started by the bootloader.
I will wait to see if the WATCHDOG_KEEP_ON will be integrated and then I
will add the feature for the omap_wdt.

Best regards;
Rostislav


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2014-09-23 13:21    [W:0.225 / U:0.020 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site