From patchwork Tue Sep 13 09:00:33 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yongji Xie X-Patchwork-Id: 9328571 X-Patchwork-Delegate: bhelgaas@google.com Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 78FD560231 for ; Tue, 13 Sep 2016 09:00:46 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 682B52863A for ; Tue, 13 Sep 2016 09:00:46 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 5CD92291FB; Tue, 13 Sep 2016 09:00:46 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id E02612863A for ; Tue, 13 Sep 2016 09:00:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756273AbcIMJAp (ORCPT ); Tue, 13 Sep 2016 05:00:45 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:50541 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755915AbcIMJAo (ORCPT ); Tue, 13 Sep 2016 05:00:44 -0400 Received: from pps.filterd (m0098410.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.17/8.16.0.17) with SMTP id u8D8wcNl082029 for ; Tue, 13 Sep 2016 05:00:44 -0400 Received: from e32.co.us.ibm.com (e32.co.us.ibm.com [32.97.110.150]) by mx0a-001b2d01.pphosted.com with ESMTP id 25e3g5670m-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Tue, 13 Sep 2016 05:00:43 -0400 Received: from localhost by e32.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! 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Violators will be prosecuted; Tue, 13 Sep 2016 03:00:40 -0600 X-IBM-Helo: d03dlp03.boulder.ibm.com X-IBM-MailFrom: xyjxie@linux.vnet.ibm.com Received: from b01cxnp22033.gho.pok.ibm.com (b01cxnp22033.gho.pok.ibm.com [9.57.198.23]) by d03dlp03.boulder.ibm.com (Postfix) with ESMTP id 548E819D8041; Tue, 13 Sep 2016 03:00:09 -0600 (MDT) Received: from b01ledav005.gho.pok.ibm.com (b01ledav005.gho.pok.ibm.com [9.57.199.110]) by b01cxnp22033.gho.pok.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id u8D90dct7078248; Tue, 13 Sep 2016 09:00:39 GMT Received: from b01ledav005.gho.pok.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id F127FAE043; Tue, 13 Sep 2016 05:00:38 -0400 (EDT) Received: from localhost (unknown [9.123.228.244]) by b01ledav005.gho.pok.ibm.com (Postfix) with ESMTP id AA327AE034; Tue, 13 Sep 2016 05:00:38 -0400 (EDT) From: Yongji Xie To: bhelgaas@google.com Cc: linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, alex.williamson@redhat.com, paulus@samba.org, aik@ozlabs.ru, gwshan@linux.vnet.ibm.com, benh@kernel.crashing.org, mpe@ellerman.id.au, zhong@linux.vnet.ibm.com Subject: [PATCH v5 3/4] PCI: Add a new option for resource_alignment to reassign alignment Date: Tue, 13 Sep 2016 17:00:33 +0800 X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1473757234-5284-1-git-send-email-xyjxie@linux.vnet.ibm.com> References: <1473757234-5284-1-git-send-email-xyjxie@linux.vnet.ibm.com> X-TM-AS-GCONF: 00 X-Content-Scanned: Fidelis XPS MAILER x-cbid: 16091309-0004-0000-0000-000010595E83 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00005753; HX=3.00000240; KW=3.00000007; PH=3.00000004; SC=3.00000185; SDB=6.00757163; UDB=6.00358995; IPR=6.00530522; BA=6.00004712; NDR=6.00000001; ZLA=6.00000005; ZF=6.00000009; ZB=6.00000000; ZP=6.00000000; ZH=6.00000000; ZU=6.00000002; MB=3.00012657; XFM=3.00000011; UTC=2016-09-13 09:00:42 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 16091309-0005-0000-0000-000078D35921 Message-Id: <1473757234-5284-4-git-send-email-xyjxie@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10432:, , definitions=2016-09-13_05:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 spamscore=0 suspectscore=1 malwarescore=0 phishscore=0 adultscore=0 bulkscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1609020000 definitions=main-1609130133 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP When using resource_alignment kernel parameter, the current implement reassigns the alignment by changing resources' size which can potentially break some drivers. For example, the driver uses the size to locate some register whose length is related to the size. This patch adds a new option "noresize" for the parameter to solve this problem. Signed-off-by: Yongji Xie --- Documentation/kernel-parameters.txt | 9 ++++++--- drivers/pci/pci.c | 37 +++++++++++++++++++++++++---------- 2 files changed, 33 insertions(+), 13 deletions(-) diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index a4f4d69..d6a340d 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -3023,9 +3023,10 @@ bytes respectively. Such letter suffixes can also be entirely omitted. window. The default value is 64 megabytes. resource_alignment= Format: - [@][:]:.[; ...] - [@]pci::\ - [::][; ...] + [@][noresize@][:] + :.[; ...] + [@][noresize@]pci:: + [::][; ...] Specifies alignment and device to reassign aligned memory resources. If is not specified, @@ -3036,6 +3037,8 @@ bytes respectively. Such letter suffixes can also be entirely omitted. instances of a device, the PCI vendor, device, subvendor, and subdevice may be specified, e.g., 4096@pci:8086:9c22:103c:198f + noresize: Don't change the resources' sizes when + reassigning alignment. ecrc= Enable/disable PCIe ECRC (transaction layer end-to-end CRC checking). bios: Use BIOS/firmware settings. This is the diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index b8357d7..37f8062 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -4946,11 +4946,13 @@ static DEFINE_SPINLOCK(resource_alignment_lock); /** * pci_specified_resource_alignment - get resource alignment specified by user. * @dev: the PCI device to get + * @resize: whether or not to change resources' size when reassigning alignment * * RETURNS: Resource alignment if it is specified. * Zero if it is not specified. */ -static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev) +static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev, + bool *resize) { int seg, bus, slot, func, align_order, count; unsigned short vendor, device, subsystem_vendor, subsystem_device; @@ -4974,6 +4976,13 @@ static resource_size_t pci_specified_resource_alignment(struct pci_dev *dev) } else { align_order = -1; } + + if (!strncmp(p, "noresize@", 9)) { + *resize = false; + p += 9; + } else + *resize = true; + if (strncmp(p, "pci:", 4) == 0) { /* PCI vendor/device (subvendor/subdevice) ids are specified */ p += 4; @@ -5045,6 +5054,7 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev) { int i; struct resource *r; + bool resize = true; resource_size_t align, size; u16 command; @@ -5058,7 +5068,7 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev) return; /* check if specified PCI is target device to reassign */ - align = pci_specified_resource_alignment(dev); + align = pci_specified_resource_alignment(dev, &resize); if (!align) return; @@ -5086,15 +5096,22 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev) } size = resource_size(r); - if (size < align) { - size = align; - dev_info(&dev->dev, - "Rounding up size of resource #%d to %#llx.\n", - i, (unsigned long long)size); + if (resize) { + if (size < align) { + size = align; + dev_info(&dev->dev, + "Rounding up size of resource #%d to %#llx.\n", + i, (unsigned long long)size); + } + r->flags |= IORESOURCE_UNSET; + r->end = size - 1; + r->start = 0; + } else { + r->flags &= ~IORESOURCE_SIZEALIGN; + r->flags |= IORESOURCE_STARTALIGN | IORESOURCE_UNSET; + r->start = max(align, size); + r->end = r->start + size - 1; } - r->flags |= IORESOURCE_UNSET; - r->end = size - 1; - r->start = 0; } /* Need to disable bridge's resource window, * to enable the kernel to reassign new resource