From: Scott Wood <scottwood@freescale•com>
To: Norbert van Bolhuis <nvbolhuis@aimvalley•nl>
Cc: "linuxppc-dev@ozlabs•org" <linuxppc-dev@ozlabs•org>
Subject: Re: Cannot wake-up from standby with MPC8313
Date: Thu, 5 Jan 2012 12:22:35 -0600 [thread overview]
Message-ID: <4F05EA6B.9040902@freescale.com> (raw)
In-Reply-To: <4F05C8C2.9070401@aimvalley.nl>
On 01/05/2012 09:58 AM, Norbert van Bolhuis wrote:
> 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?
> 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?
> 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.
-Scott
next prev parent reply other threads:[~2012-01-05 18:22 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-01-04 16:19 Cannot wake-up from standby with MPC8313 Norbert van Bolhuis
2012-01-04 21:08 ` Scott Wood
2012-01-05 15:58 ` Norbert van Bolhuis
2012-01-05 18:22 ` Scott Wood [this message]
2012-01-06 13:53 ` Norbert van Bolhuis
2012-01-06 21:03 ` Scott Wood
2012-01-13 14:13 ` Norbert van Bolhuis
2012-01-16 20:22 ` Scott Wood
2012-01-17 16:56 ` Norbert van Bolhuis
2012-01-17 22:09 ` Scott Wood
2012-01-18 10:16 ` Norbert van Bolhuis
2012-01-20 20:05 ` Scott Wood
2012-01-23 10:08 ` ehodys
-- strict thread matches above, loose matches on Subject: below --
2012-01-23 9:34 nvbolhuis
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