From patchwork Thu Feb 28 00:06:45 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shuah Khan X-Patchwork-Id: 223756 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 3F77F2C0086 for ; Thu, 28 Feb 2013 11:06:54 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752271Ab3B1AGw (ORCPT ); Wed, 27 Feb 2013 19:06:52 -0500 Received: from g4t0017.houston.hp.com ([15.201.24.20]:13631 "EHLO g4t0017.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751532Ab3B1AGw (ORCPT ); Wed, 27 Feb 2013 19:06:52 -0500 Received: from g4t0018.houston.hp.com (g4t0018.houston.hp.com [16.234.32.27]) by g4t0017.houston.hp.com (Postfix) with ESMTP id B349D3807B; Thu, 28 Feb 2013 00:06:50 +0000 (UTC) Received: from [10.152.0.222] (swa01cs005-da01.atlanta.hp.com [16.114.29.155]) by g4t0018.houston.hp.com (Postfix) with ESMTP id 23E5310267; Thu, 28 Feb 2013 00:06:46 +0000 (UTC) Message-ID: <1362010005.2808.34.camel@lorien2> Subject: [PATCH v2 1/4] pci: Add PCI_BUS_NUM() and PCI_DEVID() interfaces to return bus number and device id From: Shuah Khan Reply-To: shuah.khan@hp.com To: Joerg Roedel , bhelgaas@google.com Cc: jiang.liu@huawei.com, shemminger@vyatta.com, paulmck@linux.vnet.ibm.com, linasvepstas@gmail.com, dhowells@redhat.com, davej@redhat.com, tglx@linutronix.de, mtk.manpages@gmail.com, iommu@lists.linux-foundation.org, linux-pci@vger.kernel.org, wangyijing@huawei.com, LKML , shuahkhan@gmail.com Date: Wed, 27 Feb 2013 17:06:45 -0700 Organization: ISS-Linux X-Mailer: Evolution 3.2.3-0ubuntu6 Mime-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org pci defines PCI_DEVFN(), PCI_SLOT(), and PCI_FUNC() interfaces, however, it doesn't have interfaces to return PCI bus and PCI device id. Drivers (AMD IOMMU, and AER) implement module specific definitions for PCI_BUS() and AMD_IOMMU driver also has a module specific interface to calculate PCI device id from bus number and devfn. Add PCI_BUS_NUM and PCI_DEVID interfaces to return PCI bus number and PCI device id respectively to avoid the need for duplicate definitions in other modules. AER driver code and AMD IOMMU driver define PCI_BUS. AMD IOMMU driver defines an interface to calculate device id from bus number, and devfn pair. PCI_DEVFN(), PCI_SLOT(), and PCI_FUNC() interfaces are exported to user-space via uapi/linux/pci.h. However, in the interest to keep the new interfaces as kernel only and not export them to user-space unnecessarily, added them to linux/pci.h instead. Signed-off-by: Shuah Khan --- include/linux/pci.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/include/linux/pci.h b/include/linux/pci.h index 15472d6..95c105a 100644 --- a/include/linux/pci.h +++ b/include/linux/pci.h @@ -35,6 +35,21 @@ /* Include the ID list */ #include +/* + * The PCI interface treats multi-function devices as independent + * devices. The slot/function address of each device is encoded + * in a single byte as follows: + * + * 7:3 = slot + * 2:0 = function + * PCI_DEVFN(), PCI_SLOT(), and PCI_FUNC() are defined uapi/linux/pci.h + * In the interest of not exposing interfaces to user-space unnecessarily, + * the following kernel only defines are being added here. + */ +#define PCI_DEVID(bus, devfn) ((((u16)bus) << 8) | devfn) +/* return bus from PCI devid = ((u16)bus_number) << 8) | devfn */ +#define PCI_BUS_NUM(x) (((x) >> 8) & 0xff) + /* pci_slot represents a physical slot */ struct pci_slot { struct pci_bus *bus; /* The bus this slot is on */