From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752639Ab1G2Spd (ORCPT ); Fri, 29 Jul 2011 14:45:33 -0400 Received: from home.keithp.com ([63.227.221.253]:41708 "EHLO keithp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752392Ab1G2Spc (ORCPT ); Fri, 29 Jul 2011 14:45:32 -0400 From: Keith Packard To: Ben Brewer , dri-devel@lists.freedesktop.org, intel-gfx@lists.freedesktop.org, linux-kernel@vger.kernel.org Subject: Re: i915 SSC Patch In-Reply-To: <4E32ADC7.3080002@codethink.co.uk> References: <4E32ADC7.3080002@codethink.co.uk> User-Agent: Notmuch/0.6.1-66-ga900dda (http://notmuchmail.org) Emacs/23.3.1 (i486-pc-linux-gnu) Date: Fri, 29 Jul 2011 11:45:28 -0700 Message-ID: MIME-Version: 1.0 Content-Type: multipart/signed; boundary="=-=-="; micalg=pgp-sha1; protocol="application/pgp-signature" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org --=-=-= Content-Transfer-Encoding: quoted-printable On Fri, 29 Jul 2011 13:55:35 +0100, Ben Brewer = wrote: > I've added a global SSC (Spread Spectrum Clock) parameter to the i915=20 > driver, since having SSC enabled breaks (distorts) VGA output on some=20 > Core i5/i7 chips (see https://bugs.freedesktop.org/show_bug.cgi?id=3D3875= 0). > SSC is still enabled by default so the behaviour won't change but=20 > setting the global_use_ssc parameter will turn this feature off and=20 > allow affected devices to function correctly (notably the Dell Vostro > 3300). The question I have is why is SSC enabled on the VGA output at all? I don't see any way VGA could ever tolerate it. =2D-=20 keith.packard@intel.com --=-=-= Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (GNU/Linux) iD8DBQFOMv/IQp8BWwlsTdMRAv3CAKDCG2F1d2oUZ9/CT9n3HgAW9awl5QCfc5A9 hfiljjMp5pICsqib+90jBsQ= =TaiA -----END PGP SIGNATURE----- --=-=-=--