From mboxrd@z Thu Jan  1 00:00:00 1970
From: Chris Wilson <chris@chris-wilson.co.uk>
Subject: Re: [PATCH] drm/i915: Reset the HEAD pointer for the
 ring after writing START
Date: Thu, 7 Aug 2014 15:17:46 +0100
Message-ID: <20140807141746.GD8737@nuc-i3427.alporthouse.com>
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On Thu, Aug 07, 2014 at 03:11:17PM +0100, Chris Wilson wrote:
> Ville found an old w/a documented for g4x that suggested that we need to
> reset the HEAD after writing START. This is a useful fixup for some of
> the g4x ring initialisation woes, but as usual, not all.

Note that a slightly different form of this patch has been used by the
reporters of bug76584 without much sucess. (My gm45 works with the old
patch - it prints out the debugging information that the fudge was
applied.))
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre