From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Vetter Subject: Re: [PATCH] Revert "drm/i915/dp: Use auxch precharge value of 5 everywhere" Date: Fri, 15 Jun 2012 10:50:44 +0200 Message-ID: <20120615084840.GA4799@phenom.ffwll.local> References: <1339704455-27823-1-git-send-email-daniel.vetter@ffwll.ch> <1339704900-3993-1-git-send-email-daniel.vetter@ffwll.ch> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail-we0-f177.google.com (mail-we0-f177.google.com [74.125.82.177]) by gabe.freedesktop.org (Postfix) with ESMTP id 2FC879E801 for ; Fri, 15 Jun 2012 01:49:16 -0700 (PDT) Received: by werc12 with SMTP id c12so2126705wer.36 for ; Fri, 15 Jun 2012 01:49:15 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1339704900-3993-1-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 , DRI Development List-Id: intel-gfx@lists.freedesktop.org On Thu, Jun 14, 2012 at 10:15:00PM +0200, Daniel Vetter wrote: > This reverts commit 092945e11c5b84f66dd08f0b87fb729715d377bc. > > This commit prevents a DP screen from properly training the link. > Oddly enough it works, once the machine has been warm-booted with an > older kernel. > > According to DP docs this _should_ have been the right precharge time. > Also, the commit that originally introduces this was just general snb > DP enabling and didn't mention any specific reason for this special > value. Whatever, trust the reporter that this makes things worse and > let's just revert it. > > v2: Less spelling fail. > > Cc: Adam Jackson > Cc: Jesse Barnes > Reported-by: "Wouter M. Koolen" > Buglink: https://lkml.org/lkml/2012/6/14/301 > Signed-Off-by: Daniel Vetter No one yelled around with a better idea, so I've picked this up for fixes with cc stable. -Daniel -- Daniel Vetter Mail: daniel@ffwll.ch Mobile: +41 (0)79 365 57 48