From mboxrd@z Thu Jan  1 00:00:00 1970
From: Matthew Garrett <mjg59@srcf.ucam.org>
Subject: Re: [RFC] Reduce idle vblank wakeups
Date: Wed, 16 Nov 2011 17:11:22 +0000
Message-ID: <20111116171122.GA28222@srcf.ucam.org>
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To: Michel =?iso-8859-1?Q?D=E4nzer?= <michel@daenzer.net>
Cc: intel-gfx@lists.freedesktop.org, dri-devel@lists.freedesktop.org, Mario Kleiner <mario.kleiner@tuebingen.mpg.de>
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On Wed, Nov 16, 2011 at 06:03:15PM +0100, Michel D=E4nzer wrote:

> I thought the main reason for the delay wasn't broken hardware but to
> avoid constantly ping-ponging the vblank IRQ between on and off with
> apps which regularly neeed the vblank counter value, as that could make
> the counter unreliable. Maybe I'm misremembering though.

If turning it on and off results in the counter value being wrong then =

surely that's a hardware problem? I've tested that turning it on and off =

between every IRQ still gives valid counter values on sandybridge.

-- =

Matthew Garrett | mjg59@srcf.ucam.org