On Thu, Nov 12, 2009 at 11:43 AM, Albrecht Dreß <albrecht.dr...@arcor.de> wrote: > Add the "fsl,wdt-on-boot" OF property as to reserve a GPT as WDT which may > be a requirement in safety-related (e.g. ISO/EN 61508) applications. > > Signed-off-by: Albrecht Dreß <albrecht.dr...@arcor.de> > > --- > > Change against v1: rename the new property. > > Documentation/powerpc/dts-bindings/fsl/mpc5200.txt | 17 ++++++++++++++++- > 1 files changed, 16 insertions(+), 1 deletions(-) > > diff --git a/Documentation/powerpc/dts-bindings/fsl/mpc5200.txt > b/Documentation/powerpc/dts-bindings/fsl/mpc5200.txt > index 8447fd7..ddd5ee3 100644 > --- a/Documentation/powerpc/dts-bindings/fsl/mpc5200.txt > +++ b/Documentation/powerpc/dts-bindings/fsl/mpc5200.txt > @@ -103,7 +103,22 @@ fsl,mpc5200-gpt nodes > --------------------- > On the mpc5200 and 5200b, GPT0 has a watchdog timer function. If the board > design supports the internal wdt, then the device node for GPT0 should > -include the empty property 'fsl,has-wdt'. > +include the empty property 'fsl,has-wdt'. Note that this does not activate > +the watchdog. The timer will function as a GPT if the timer api is used, and > +it will function as watchdog if the watchdog device is used. The watchdog > +mode has priority over the gpt mode, i.e. if the watchdog is activated, any > +gpt api call to this timer will fail with -EBUSY. > + > +If you add the property > + fsl,wdt-on-boot = <n>; > +GPT0 will be marked as in-use watchdog, i.e. blocking every gpt access to it. > +If n>0, the watchdog is started with a timeout of n seconds. If n=0, the > +configuration of the watchdog is not touched. This is useful in two cases: > +- just mark GPT0 as watchdog, blocking gpt accesses, and configure it later; > +- do not touch a configuration assigned by the boot loader which supervises > + the boot process itself. > + > +The watchdog will respect the CONFIG_WATCHDOG_NOWAYOUT option.
I think it would be better to use a device tree property to enable up NOWAYOUT. The static config isn't multiplatform-friendly. Thoughts? Otherwise, this looks good to me. g. -- Grant Likely, B.Sc., P.Eng. Secret Lab Technologies Ltd. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev