From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7659DC433E0 for ; Wed, 27 May 2020 18:18:50 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5DFFB20FC3 for ; Wed, 27 May 2020 18:18:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590603530; bh=IlJRE+s/Xn0kFANnhdpCDcIhPKRLpygy8ad6xlPlHjQ=; h=Date:From:To:Cc:Subject:In-Reply-To:List-ID:From; b=aZ1c33ly9RvA9Y+6nu8zK2nMf7z/RP26leFcPMFp0dbMDpri/L3A5HgQAWu83ZY4E yM7C4Y/7qu7TtD/QrA41/zdkBY+WQ1W0myQlICoN1Yab1TjNdSnhfrVz8OL80ZnN5j 7MUjRMj4k8hLYdNlpv/iP5FK3A05fU6E+tdv+mm8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391935AbgE0SSp (ORCPT ); Wed, 27 May 2020 14:18:45 -0400 Received: from mail.kernel.org ([198.145.29.99]:54726 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391932AbgE0SSp (ORCPT ); Wed, 27 May 2020 14:18:45 -0400 Received: from localhost (mobile-166-175-190-200.mycingular.net [166.175.190.200]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 3CF692075A; Wed, 27 May 2020 18:18:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1590603524; bh=IlJRE+s/Xn0kFANnhdpCDcIhPKRLpygy8ad6xlPlHjQ=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=nIx2hX8lM30uXBDTL7TuhND9kQ3G+qZ++mUq5WECUp59CfqdUpYK43QoUK7AXlVPf KxTUevqFBycL9TlKq7SmWveEDn1K/rg1pDaaEGJos75PWipKFqulr3bGwuDJBHuVi1 7/+Jn7myhnHFa+KsZWLZ+HqvliJJB2ISAncHJDyU= Date: Wed, 27 May 2020 13:18:42 -0500 From: Bjorn Helgaas To: Zhangfei Gao Cc: Joerg Roedel , Bjorn Helgaas , Arnd Bergmann , Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , "Rafael J. Wysocki" , Len Brown , jean-philippe , Greg Kroah-Hartman , Herbert Xu , kenneth-lee-2012@foxmail.com, Wangzhou , linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org, iommu@lists.linux-foundation.org, linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-pci@vger.kernel.org Subject: Re: [PATCH 0/2] Introduce PCI_FIXUP_IOMMU Message-ID: <20200527181842.GA256680@bjorn-Precision-5520> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1590493749-13823-1-git-send-email-zhangfei.gao@linaro.org> Sender: linux-crypto-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-crypto@vger.kernel.org On Tue, May 26, 2020 at 07:49:07PM +0800, Zhangfei Gao wrote: > Some platform devices appear as PCI but are actually on the AMBA bus, > and they need fixup in drivers/pci/quirks.c handling iommu_fwnode. > Here introducing PCI_FIXUP_IOMMU, which is called after iommu_fwnode > is allocated, instead of reusing PCI_FIXUP_FINAL since it will slow > down iommu probing as all devices in fixup final list will be > reprocessed, suggested by Joerg, [1] Is this slowdown significant? We already iterate over every device when applying PCI_FIXUP_FINAL quirks, so if we used the existing PCI_FIXUP_FINAL, we wouldn't be adding a new loop. We would only be adding two more iterations to the loop in pci_do_fixups() that tries to match quirks against the current device. I doubt that would be a measurable slowdown. > For example: > Hisilicon platform device need fixup in > drivers/pci/quirks.c handling fwspec->can_stall, which is introduced in [2] > > +static void quirk_huawei_pcie_sva(struct pci_dev *pdev) > +{ > + struct iommu_fwspec *fwspec; > + > + pdev->eetlp_prefix_path = 1; > + fwspec = dev_iommu_fwspec_get(&pdev->dev); > + if (fwspec) > + fwspec->can_stall = 1; > +} > + > +DECLARE_PCI_FIXUP_IOMMU(PCI_VENDOR_ID_HUAWEI, 0xa250, quirk_huawei_pcie_sva); > +DECLARE_PCI_iFIXUP_IOMMU(PCI_VENDOR_ID_HUAWEI, 0xa251, quirk_huawei_pcie_sva); > > [1] https://www.spinics.net/lists/iommu/msg44591.html > [2] https://www.spinics.net/lists/linux-pci/msg94559.html If you reference these in the commit logs, please use lore.kernel.org links instead of spinics. > Zhangfei Gao (2): > PCI: Introduce PCI_FIXUP_IOMMU > iommu: calling pci_fixup_iommu in iommu_fwspec_init > > drivers/iommu/iommu.c | 4 ++++ > drivers/pci/quirks.c | 7 +++++++ > include/asm-generic/vmlinux.lds.h | 3 +++ > include/linux/pci.h | 8 ++++++++ > 4 files changed, 22 insertions(+) > > -- > 2.7.4 >