[U-Boot] [PATCH 2/2] at91sam9263ek: active watchdog support via at91sam9263ek_wdt_config

Alessandro Rubini
2009-06-15T13:01:20Z

>> But you have to delete hw_watchdog_init().
>> If you set there MR then linux won't be able to do it.
>> The patch needs only the WATCHDOG_RESET() and nothing more.

I agree.

> you need to update linux, the watchdog can be enable in u-boot
> but as it can only be disable once if u-boot or any other bootloader init
> we can not disable it
> so in this case linux will just have to buy time to the watchdog

On the sam926x processors It can only be confitured once. So Giulio
is right: u-boot shouldn't configure it, just kick it any now and then.

When a client asked to used the watchdog on the 9260 I chose not to
disable it in at91boot nor in u-boot. Then Linux (i.e., the final
user) could do whatever was fit: either disable it, enable it with a
faster timeout or leave it alone (at 13s or whatever the default is)
until some application sets a policy.

I don't like this hardware choice of "configure once only":
never-disable makes sense, but never-enable doesn't, in my
opinion. But based on that the right thing for u-boot is not
configuring it a all, or we loose flexibility in later stages.

/alessandro