From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mika Kuoppala <mika.kuoppala@linux.intel.com>
Subject: Re: [PATCH 1/3] drm/i915: Implement Selective Write
 workaround for Haswell GT1
Date: Fri, 28 Dec 2018 15:03:52 +0200
Message-ID: <877eft6bwn.fsf@gaia.fi.intel.com>
References: <20181228123626.1465-1-chris@chris-wilson.co.uk>
Mime-Version: 1.0
Content-Type: text/plain; charset="utf-8"
Content-Transfer-Encoding: base64
Return-path: <intel-gfx-bounces@lists.freedesktop.org>
Received: from mga11.intel.com (mga11.intel.com [192.55.52.93])
 by gabe.freedesktop.org (Postfix) with ESMTPS id 3758F6E98A
 for <intel-gfx@lists.freedesktop.org>; Fri, 28 Dec 2018 13:05:23 +0000 (UTC)
In-Reply-To: <20181228123626.1465-1-chris@chris-wilson.co.uk>
List-Unsubscribe: <https://lists.freedesktop.org/mailman/options/intel-gfx>,
 <mailto:intel-gfx-request@lists.freedesktop.org?subject=unsubscribe>
List-Archive: <https://lists.freedesktop.org/archives/intel-gfx>
List-Post: <mailto:intel-gfx@lists.freedesktop.org>
List-Help: <mailto:intel-gfx-request@lists.freedesktop.org?subject=help>
List-Subscribe: <https://lists.freedesktop.org/mailman/listinfo/intel-gfx>,
 <mailto:intel-gfx-request@lists.freedesktop.org?subject=subscribe>
Errors-To: intel-gfx-bounces@lists.freedesktop.org
Sender: "Intel-gfx" <intel-gfx-bounces@lists.freedesktop.org>
To: Chris Wilson <chris@chris-wilson.co.uk>, intel-gfx@lists.freedesktop.org
Cc: Ben Widawsky <ben@bwidawsk.net>
List-Id: intel-gfx@lists.freedesktop.org
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=