From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:62965 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752151AbcF3Kxq (ORCPT ); Thu, 30 Jun 2016 06:53:46 -0400 Received: from pps.filterd (m0098419.ppops.net [127.0.0.1]) by mx0b-001b2d01.pphosted.com (8.16.0.11/8.16.0.11) with SMTP id u5UArXn2128489 for ; Thu, 30 Jun 2016 06:53:45 -0400 Received: from e28smtp09.in.ibm.com (e28smtp09.in.ibm.com [125.16.236.9]) by mx0b-001b2d01.pphosted.com with ESMTP id 23uvafhk5v-1 (version=TLSv1.2 cipher=AES256-SHA bits=256 verify=NOT) for ; Thu, 30 Jun 2016 06:53:44 -0400 Received: from localhost by e28smtp09.in.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Thu, 30 Jun 2016 16:23:30 +0530 From: Yongji Xie To: linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-doc@vger.kernel.org Cc: bhelgaas@google.com, alex.williamson@redhat.com, aik@ozlabs.ru, benh@kernel.crashing.org, paulus@samba.org, mpe@ellerman.id.au, corbet@lwn.net, warrier@linux.vnet.ibm.com, zhong@linux.vnet.ibm.com, nikunj@linux.vnet.ibm.com, gwshan@linux.vnet.ibm.com Subject: [PATCH v3 3/7] PCI: Do not disable memory decoding in pci_reassigndev_resource_alignment() Date: Thu, 30 Jun 2016 18:53:09 +0800 In-Reply-To: <1467283993-3185-1-git-send-email-xyjxie@linux.vnet.ibm.com> References: <1467283993-3185-1-git-send-email-xyjxie@linux.vnet.ibm.com> Message-Id: <1467283993-3185-4-git-send-email-xyjxie@linux.vnet.ibm.com> Sender: linux-pci-owner@vger.kernel.org List-ID: We should not disable memory decoding when we reassign alignment in pci_reassigndev_resource_alignment(). It's meaningless and have some side effect. For example, some fixup functions such as quirk_e100_interrupt() read PCI_COMMAND_MEMORY to know whether the devices has been initialized by the firmware or not. If we disable memory decoding here, these functions will get a wrong information that the devices was not initialized by the firmware which may cause a wrong fixup. Besides, disabling memory decoding may also break some devices that need to have memory decoding always-on during probing. Signed-off-by: Yongji Xie --- drivers/pci/pci.c | 8 +------- 1 file changed, 1 insertion(+), 7 deletions(-) diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c index 6ae02de..6241cfc 100644 --- a/drivers/pci/pci.c +++ b/drivers/pci/pci.c @@ -4820,7 +4820,6 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev) int i; struct resource *r; resource_size_t align, size; - u16 command; /* We should never try to reassign VF's alignment */ if (dev->is_virtfn) @@ -4838,12 +4837,7 @@ void pci_reassigndev_resource_alignment(struct pci_dev *dev) return; } - dev_info(&dev->dev, - "Disabling memory decoding and releasing memory resources.\n"); - pci_read_config_word(dev, PCI_COMMAND, &command); - command &= ~PCI_COMMAND_MEMORY; - pci_write_config_word(dev, PCI_COMMAND, command); - + dev_info(&dev->dev, "Releasing memory resources.\n"); for (i = 0; i < PCI_BRIDGE_RESOURCES; i++) { r = &dev->resource[i]; if (!(r->flags & IORESOURCE_MEM)) -- 1.7.9.5