From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759698AbZIPQeF (ORCPT ); Wed, 16 Sep 2009 12:34:05 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759681AbZIPQd7 (ORCPT ); Wed, 16 Sep 2009 12:33:59 -0400 Received: from mail-bw0-f219.google.com ([209.85.218.219]:55005 "EHLO mail-bw0-f219.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759662AbZIPQd4 convert rfc822-to-8bit (ORCPT ); Wed, 16 Sep 2009 12:33:56 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type:content-transfer-encoding; b=w/9n9Ng2Gtx8hiRLdmvHhBIDEswm4gODJcgGAg5LZ5FiFDbLo4qORKOJpoGTbjiHzm TfRkpbCq7/EcvBpgusY/QugBPFIDafacHE0rrWwek2mpoFvbfANil/ZDOq56n1vh7tey QAlJX3N/mNH62VE22zWw0Cpsl84lbhRoHD4g0= MIME-Version: 1.0 In-Reply-To: <20090916090907.2538fca1@jbarnes-g45> References: <200909160910.24329.neuro@o2.pl> <20090916090907.2538fca1@jbarnes-g45> Date: Wed, 16 Sep 2009 12:33:58 -0400 Message-ID: Subject: Re: Explicitly putting a PCI device to ACPI D0 From: Alex Deucher To: Jesse Barnes Cc: Michal Witkowski , linux-kernel@vger.kernel.org Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 16, 2009 at 12:09 PM, Jesse Barnes wrote: > On Wed, 16 Sep 2009 09:10:24 +0200 > Michal Witkowski wrote: > >> Hi, >> >> I've been searching for my answer for a while now, and since I >> haven't found it anywhere, I've decided to post to LKML, hoping that >> someone here can help me. >> >> First, I'll explain the background of my problem. My grief is the >> switchable GPU in my Lenovo Ideapad U330. The BIOS supports two >> options "Discrete only" (only the ATI card is visible on the BUS) and >> "Switchable" (both ATI and Intel card visible on the bus). The >> problem is the lack of a third option "Integrated", in which only the >> Intel card would be powered off. Lenovo refused to introduce such an >> option into the BIOS, stating that it's a feature request and not a >> bug. >> >> To save battery power I'd like to be able to run on the Intel card. >> However, with the "Switchable" option, powertop indicates huge power >> usage (24W), which can only be explained by the fact that both cards >> draw power. >> >> Thus, my question is the following: >> Is there a way to explicitly put a device into ACPI D0? I would like >> to do that to the ATI card on boot. >> >> I've tried the following code: >> http://ftp.chg.ru/pub/parallel/scyld/diag/pci-config.c >> But it didn't work (the ATI card was still on). > > Your best bet might be to load a driver for the ATI card that puts it > into PCI D3 state until used.  There may be other ways to save power on > the disabled part as well... > > Alex, is this something you've looked at at all? The xf86-video-ati ddx can turn off the displays and reduce the clocks and pcie lanes, but I haven't sorted out all the D3 stuff yet. As for the switchable graphics, you might find the page below useful. No idea if it will work or fry your hardware: http://ubuntuforums.org/showthread.php?p=7944950 Alex