From patchwork Fri Jun 8 08:01:31 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Hao, Xudong" X-Patchwork-Id: 163733 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 5DAFBB6FBB for ; Fri, 8 Jun 2012 18:02:23 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933240Ab2FHIBx (ORCPT ); Fri, 8 Jun 2012 04:01:53 -0400 Received: from mga09.intel.com ([134.134.136.24]:62602 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933001Ab2FHIBV (ORCPT ); Fri, 8 Jun 2012 04:01:21 -0400 Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga102.jf.intel.com with ESMTP; 08 Jun 2012 01:01:21 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.67,352,1309762800"; d="scan'208";a="149938485" Received: from xhao-dev.sh.intel.com (HELO localhost.localdomain) ([10.239.48.48]) by orsmga001.jf.intel.com with ESMTP; 08 Jun 2012 01:01:19 -0700 From: Xudong Hao To: bhelgaas@google.com Cc: linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, avi@redhat.com, alex.williamson@redhat.com, ddutile@redhat.com, myron.stowe@redhat.com, xiantao.zhang@intel.com, xudong.hao@intel.com Subject: [PATCH 3/4] Enable OBFF before device is used by driver Date: Fri, 8 Jun 2012 16:01:31 +0800 Message-Id: <1339142492-13625-4-git-send-email-xudong.hao@intel.com> X-Mailer: git-send-email 1.5.5 In-Reply-To: <1339142492-13625-1-git-send-email-xudong.hao@intel.com> References: <1339142492-13625-1-git-send-email-xudong.hao@intel.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Enable OBFF(optimized buffer flush/fill) in pci_enable_device() function, make sure this feature is enabled before device is used by driver. Signed-off-by: Xudong Hao --- drivers/pci/pci.c | 9 +++++++++ 1 files changed, 9 insertions(+), 0 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 5e5e3ad..35127c1 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -1144,11 +1144,20 @@ static void pci_enable_dev_caps(struct pci_dev *dev) * tolerance for snooped & unsnooped memory transactions. */ pci_enable_ltr(dev); + + /* + * OBFF (optimized buffer flush/fill), where supported, + * can help improve energy efficiency by giving devices + * information about when interrupts and other activity + * will have a reduced power impact. + */ + pci_enable_obff(dev, PCI_EXP_OBFF_SIGNAL_L0); } static void pci_disable_dev_caps(struct pci_dev *dev) { pci_disable_ltr(dev); + pci_disable_obff(dev); } static int do_pci_enable_device(struct pci_dev *dev, int bars)