From patchwork Fri Jun 8 08:01:29 2012 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Hao, Xudong" X-Patchwork-Id: 163734 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 47A07B6FBA for ; Fri, 8 Jun 2012 18:03:34 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932684Ab2FHICq (ORCPT ); Fri, 8 Jun 2012 04:02:46 -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 S932317Ab2FHIBR (ORCPT ); Fri, 8 Jun 2012 04:01:17 -0400 Received: from orsmga001.jf.intel.com ([10.7.209.18]) by orsmga102.jf.intel.com with ESMTP; 08 Jun 2012 01:01:17 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.67,352,1309762800"; d="scan'208";a="149938438" Received: from xhao-dev.sh.intel.com (HELO localhost.localdomain) ([10.239.48.48]) by orsmga001.jf.intel.com with ESMTP; 08 Jun 2012 01:01:15 -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 1/4] Add pci_obff_supported() function. Date: Fri, 8 Jun 2012 16:01:29 +0800 Message-Id: <1339142492-13625-2-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 Add pci_obff_supported() function and use it by obff relative function. Signed-off-by: Xudong Hao --- drivers/pci/pci.c | 30 ++++++++++++++++++++++++------ 1 files changed, 24 insertions(+), 6 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 447e834..a70093b 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -39,6 +39,7 @@ EXPORT_SYMBOL(pci_pci_problems); unsigned int pci_pm_d3_delay; +static bool pci_obff_supported(struct pci_dev *dev); static void pci_pme_list_scan(struct work_struct *work); static LIST_HEAD(pci_pme_list); @@ -2071,6 +2072,27 @@ void pci_disable_ido(struct pci_dev *dev, unsigned long type) EXPORT_SYMBOL(pci_disable_ido); /** + * pci_obff_supported - check whether a device supports OBFF + * @dev: PCI device + * + * RETURNS: + * True if @dev supports optimized buffer flush/fill, false otherwise. + */ +static bool pci_obff_supported(struct pci_dev *dev) +{ + int pos; + u32 cap; + + pos = pci_pcie_cap(dev); + if (!pos) + return false; + + pci_read_config_dword(dev, pos + PCI_EXP_DEVCAP2, &cap); + + return cap & PCI_EXP_OBFF_MASK; +} + +/** * pci_enable_obff - enable optimized buffer flush/fill * @dev: PCI device * @type: type of signaling to use @@ -2096,17 +2118,13 @@ int pci_enable_obff(struct pci_dev *dev, enum pci_obff_signal_type type) u16 ctrl; int ret; - if (!pci_is_pcie(dev)) + if (!pci_obff_supported(dev)) return -ENOTSUPP; pos = pci_pcie_cap(dev); if (!pos) return -ENOTSUPP; - pci_read_config_dword(dev, pos + PCI_EXP_DEVCAP2, &cap); - if (!(cap & PCI_EXP_OBFF_MASK)) - return -ENOTSUPP; /* no OBFF support at all */ - /* Make sure the topology supports OBFF as well */ if (dev->bus) { ret = pci_enable_obff(dev->bus->self, type); @@ -2149,7 +2167,7 @@ void pci_disable_obff(struct pci_dev *dev) int pos; u16 ctrl; - if (!pci_is_pcie(dev)) + if (!pci_obff_supported(dev)) return; pos = pci_pcie_cap(dev);