Subject: Re: ACPI PM Timer vs. C1 halt issue
From: john stultz <johnstul@us.ibm.com>
To: "Prakash K. Cheemplavam" <PrakashKC@gmx.de>
Cc: lkml <linux-kernel@vger.kernel.org>, Andrew Morton <akpm@osdl.org>,
       Linus Torvalds <torvalds@osdl.org>, len.brown@intel.com,
       Dominik Brodowski <linux@brodo.de>
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	 <1078870289.12084.8.camel@cog.beaverton.ibm.com>  <404E4913.3020005@gmx.de>
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Date: Wed, 10 Mar 2004 13:49:32 -0800
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On Tue, 2004-03-09 at 14:45, Prakash K. Cheemplavam wrote:
> john stultz wrote:
> > On Tue, 2004-03-09 at 13:35, Prakash K. Cheemplavam wrote:
> > 
> >>I found out what causes higher idle temps when using mm-sources and 
> >>2.6.4-rc vanilla sources: If I use PM Timer as timesource, it seems the 
> >>C1 halt isn't properly called, at least CPU disconnect doesn't seem to 
> >>work, thus leaving my CPU as hot as without disconnect.
> [snip]
> > 
> > Sounds like a bug. I'm not very familiar w/ the ACPI cpu power states,
> > is there anything you have to do to trigger C1 Halt? Or is it just
> > called in the idle loop?
> 
> It should be called within the idle loop.

Hmm. I'm still stumped. Looking at acpi_processor_idle(), the C1 state
doesn't touch the ACPI PM timer. The C2 and C3 states do, but they just
read.  

Dominik: Do you have a clue on this?

thanks
-john

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