From mboxrd@z Thu Jan  1 00:00:00 1970
From: Chris Wilson <chris@chris-wilson.co.uk>
Subject: Re: TIMESTAMP register
Date: Wed, 18 Apr 2012 09:05:43 +0100
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To: "Lawrynowicz, Jacek" <jacek.lawrynowicz@intel.com>, Ben Widawsky <ben@bwidawsk.net>, Daniel Vetter <daniel@ffwll.ch>, "Jesse Barnes (jbarnes@virtuousgeek.org)" <jbarnes@virtuousgeek.org>
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On Wed, 18 Apr 2012 07:53:36 +0000, "Lawrynowicz, Jacek" <jacek.lawrynowicz@intel.com> wrote:
> But how would I synchronize GPU and CPU clocks without access to the TIMESTAMP 
> register?
Issue a pipecontrol, compensate for the execution latency.

> And are you sure that over time both clocks won't desynchronize?
Given the assurrances made in the bspec, I'm certain the timestamp
will prove to be bogus and drift.
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre