From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chris Wilson Subject: Re: [PATCH] i915: Initialize panel timing registers if VBIOS did not. Date: Fri, 08 Oct 2010 10:58:40 +0100 Message-ID: <89k77n$p5t7tl@fmsmga001.fm.intel.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by gabe.freedesktop.org (Postfix) with ESMTP id 87E0BA0A24 for ; Fri, 8 Oct 2010 02:58:45 -0700 (PDT) In-Reply-To: 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: Bryan Freed , Jesse Barnes Cc: intel-gfx@lists.freedesktop.org, Olof Johansson , Mandeep Baines List-Id: intel-gfx@lists.freedesktop.org On Thu, 7 Oct 2010 17:05:46 -0700, Bryan Freed wrote: > The time between start of the pixel clock and backlight enable is a basic > panel timing constraint. If the Panel Power On/Off registers are found > to be 0, assume we are booting without VBIOS initialization and set these > registers to something reasonable. That looks cleaner. Obviously my only concern is what happens if we ever see a second device that posts without setting up the registers. We may as well compile in the VBT for every single manufactured device... Or we could add a ROM table the manufacturers must include that provides the necessary register values for their hardware. There must be some replacement for the BIOS, a device description table at least? Does any one have a strong "this will damage my hardware" objection? Are the values safe enough for *any* device? -Chris -- Chris Wilson, Intel Open Source Technology Centre