From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: Re: Small series to enable OpRegion->VBT Date: Tue, 24 Aug 2010 15:37:47 +0100 Message-ID: <89kc63$hrta0i@fmsmga002.fm.intel.com> References: <1282639383-26988-1-git-send-email-chris@chris-wilson.co.uk> <1282659768.17843.37718.camel@atropine> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga11.intel.com (mga11.intel.com [192.55.52.93]) by gabe.freedesktop.org (Postfix) with ESMTP id A0DED9E7B6 for ; Tue, 24 Aug 2010 07:38:04 -0700 (PDT) In-Reply-To: <1282659768.17843.37718.camel@atropine> 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-gfx@lists.freedesktop.org List-Id: intel-gfx@lists.freedesktop.org On Tue, 24 Aug 2010 10:22:48 -0400, Adam Jackson wrote: > I'd be a little more comfortable with this series if we tried to find > VBT in VBIOS first. The way around you have it in patch 3 we'll likely > be changing behaviour on existing machines, since we've not been paying > any attention to what OpRegion's VBT contains before now. I mean, I'm > not going to insist on it, but I'll reserve the right to say I told you > so. That would be the conservative approach. The docs are adamant that OpRegion should be used in preference to any legacy approach. But nobody reads those docs, at least not whilst writing the BIOS or during review. One of the goals here is to solve the mystery of what happens to the VBT on docking and whether new devices appear via the OpRegion, through the ROM or never. If you do have one of the affected HP systems, can you at try the patch and grab the /sys/kernel/debug/dri/0/i915_opregion before and after docking? It's a fair point though, with either approach we are without a doubt going to need quirks at some point. Does anybody have a strong preference for the precedence order? My vote is to rid the world of BIOS and ACPI but the problem seems to be only getting worse over time. -- Chris Wilson, Intel Open Source Technology Centre