Re: [PATCHv3 0/9] ARM: OMAP2+: AM33XX: Add suspend-resume support

[Kevin Hilman <khilman@linaro.org>]

On Wed, Sep 4, 2013 at 8:12 AM, Russ Dill <Russ.Dill@ti.com> wrote:
> On Wed, Sep 4, 2013 at 8:01 AM, Kevin Hilman <khilman@linaro.org> wrote:
>> Hi Dave,
>>
>>> Thanks for taking the time to try this out, it does seem there are a few
>>> kinks with BeagleBone Black but we'll get those worked out.
>>
>> I also just noticed that wake from RTC isn't working, but wake from
>> serial console does.  Does RTC wake work for you?  (I use rtcwake -m
>> mem -s4)
>>
>> Kevin
>
> On Beaglebone white or black?

White.

> For PG 1.0 (Beaglebone white) there is
> the following errata:
>
> "RTC: 32.768-kHZ Clock is Gating Off"
>
> Details The RTC has a clock gating issue that stops the internal
> 32.768-kHz clock when the VDD_CORE voltage domain drops below the
> recommended operating range or the PWRONRSTn input terminal is held
> low. This issue has the following side effects:
>
> - The RTC counters stop incrementing when the 32.768-kHz clock is
> gated. This causes the RTC to lose time while the clock is gated.
>
> - A wakeup event applied to the EXT_WAKEUP input terminal is masked if
> the EXT_WAKEUP_DB_EN bit in the RTC PMIC register (0x98) is set to 1
> which enables the de-bounce function for the EXT_WAKEUP input. This
> occurs because the 32.768-kHz clock is being used to clock the
> de-bounce circuit.

I'm not using your VDD_CORE scaling series (or maybe the firmware is
scaling VDD_CORE?)

Anyways, thanks for the info on the errata, that must be what's causing it.

Kevin