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Date: Mon, 26 Sep 2011 10:13:23 +0200
From: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
To: Mauro Carvalho Chehab <mchehab@redhat.com>
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Subject: Re: cx231xx: DMA problem on ARM
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Hello Mauro,

Le Fri, 23 Sep 2011 23:15:54 -0300,
Mauro Carvalho Chehab <mchehab@redhat.com> a écrit :

> > And still the result is the same: we get a first frame, and then
> > nothing more, and we have a large number of error messages in the
> > kernel logs.
> 
> I don't think that this is related to the power manager anymore. It can
> be related to cache coherency and/or to iommu support.

As you suspected, increasing PWR_SLEEP_INTERVAL didn't change anything.
What do you suggest to track down the potential cache coherency issues ?

Best regards,

Thomas
-- 
Thomas Petazzoni, Free Electrons
Kernel, drivers, real-time and embedded Linux
development, consulting, training and support.
http://free-electrons.com