Re: Cannot wake-up from standby with MPC8313

On 01/05/12 19:22, Scott Wood wrote:

On 01/05/2012 09:58 AM, Norbert van Bolhuis wrote:

quoted

thanks for your response.

not setting MSR_POW gives same result.

OK, so you're not getting an interrupt regardless of low-power state.

Check whether the interrupt is getting masked during standby preparation.

Does the interrupt handler run when you're not trying to enter standby?

The GPIO/UART interrupt nor the PMC interrupt are being masked during standby
preperation.
The GPIO/UART interrupt works fine in "operational" mode.
The PMC interrupt I do not know, is it possible to to get PMC interrupt
without going to standby or deep-sleep ?
In anyway there is no PMC interrupt for NAP mode (if kernel.powersave-nap=1).

quoted

if I set kernel.powersave-nap=1 it works fine,

What is "it"?  Do you mean that powersave-nap doesn't break things, or
that standby works when you specify that?

I mean powersave-nap itself seems to work and does not break things.

quoted

so apparently NAP/DOZE mode does work (if CPU is idle). This saves almost no
power though. Standby mode saves about 300-500 mW.

The problem could well be our board though, today I learned it does
work by connecting an (inactive) JTAG debugger.
Also, on another board it always works.

You mean connecting a JTAG but not doing anything with it made
wake-from-standby work?

There was a bug like that on early revisions of the mpc8313erdb board --
though in that case if you had a bad board the system would hang
whenever you access any PMC register.  I'm not sure what the mechanism
of failure was; IIRC the fix was adding a resistor.

yes, connecting a JTAG but not doing anything with it makes
wake-from-standby work.

I don't know what's wrong with (some of) our boards... it looks
like external interrupts are blocked and/or core stays in reset..

I doubt there's a SW PMC race/deadlock that causes this.


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NvBolhuis