From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: Re: [PATCH] drm/i915: rip out pre-production ilk cpu edp w/a Date: Thu, 13 Sep 2012 13:38:05 +0100 Message-ID: <6c3329$61hlba@orsmga002.jf.intel.com> References: <1347534809-13341-1-git-send-email-daniel.vetter@ffwll.ch> Mime-Version: 1.0 Content-Type: multipart/mixed; boundary="===============1087600486==" Return-path: Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by gabe.freedesktop.org (Postfix) with ESMTP id AF611A0E3D for ; Thu, 13 Sep 2012 05:38:20 -0700 (PDT) In-Reply-To: <1347534809-13341-1-git-send-email-daniel.vetter@ffwll.ch> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org Errors-To: intel-gfx-bounces+gcfxdi-intel-gfx=m.gmane.org@lists.freedesktop.org To: Intel Graphics Development Cc: Daniel Vetter List-Id: intel-gfx@lists.freedesktop.org --===============1087600486== Content-Type: text/plain On Thu, 13 Sep 2012 13:13:29 +0200, Daniel Vetter wrote: > While reading docs I've noticed that this special workaround to select > the 1.6 GHz DP clock only applies to pre-production ilk machines. > Since the registers we're touching here are rather undocumented and > might be harmful on later chips, rip it out. > > For the Bspec reference of this w/a look in "vol4g CPU Display > Registers [DevILK]", Section 4.1.7.1 "DP_A—DisplayPort A > Control Register", "DP_PLL_Frequency_Select". > > Signed-off-by: Daniel Vetter The spec definitely says DevILK-A, are we sure it got excised in production machines? Once a w/a is implemented by the Windows driver they have a tendency to linger... So can you instead replace the w/a with a message to remind us about the possibilty of failure of the PLL to change frequencies. -Chris -- Chris Wilson, Intel Open Source Technology Centre --===============1087600486== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx --===============1087600486==--