[U-Boot] Periodic task

[Heiko Schocher <hs@denx.de>]

Hello Ran,

Am 26.08.2015 um 08:09 schrieb Ran Shalit:
> On Wed, Aug 26, 2015 at 7:45 AM, Heiko Schocher <hs@denx.de> wrote:
>> Hello Ran,
>>
>> Am 25.08.2015 um 22:03 schrieb Ran Shalit:
>>>
>>> Hello,
>>>
>>> I need to do some periodic very simple task during u-boot prompt
>>> (while u-boot wais for commands). The task is very simple, just
>>> writing into a watchdog refresh register.
>>> But it seems that it's very difficult to "hack" u-boot with such periodic
>>> task.
>>> I see that main loop is waiting in loop for characters in a call to
>>> getc, which is a blocking command. If it was non-blocking, it might
>>> have help me. I'm not sure if there is a way to replace the getc with
>>> a non-blocking call.
>>>
>>> Does anyone have any idea if there is some simple way to do periodic
>>> task in u-boot  ?
>>
>>
>> As you want to trigger a watchdog, have a look at
>> u-boot:/drivers/watchdog
>> and grep the U-Boot code for
>> CONFIG_WATCHDOG
>> CONFIG_HW_WATCHDOG
>>
>> bye,
>> Heiko
>> --
>
>
> Hi Heiko,
>
> That's a great suggestion.
> I can understand from this, that there is timer interrupt in the
> background for the watchdog refresh activity.

I do not know anything about your hw ... but timer interrupt is not
necessary.

WATCHDOG_RESET is called from the U-Boot code ..
see definition in include/watchdog.h

bye,
Heiko
-- 
DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany