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=-17.6 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=unavailable 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 55953C433E6 for ; Mon, 1 Feb 2021 07:37:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0C5B864E35 for ; Mon, 1 Feb 2021 07:37:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232209AbhBAHhC (ORCPT ); Mon, 1 Feb 2021 02:37:02 -0500 Received: from us-smtp-delivery-124.mimecast.com ([63.128.21.124]:33297 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229558AbhBAHhB (ORCPT ); Mon, 1 Feb 2021 02:37:01 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612164934; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=xIIyMdYX4ss9YyVUqtXNFUPDM8yR2OxXJHbAJpn06hc=; b=efZjtEizggs2z14M4Xk9lvTNpy5aNQnzVTuWdVpWf1hHKvn/332BY6iUOkwW2+BaAJ3djt ogDbTLvinIYVmziT4xelbr5ceP3eoqns66HlCpva3XmzE2m619Qnis9LaK71Dv45YdG0Mm /Ejv62C4TJx4hO5xPJMvk5gh2KVge1w= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-412-O7QH08jgPK6rXsyzh-FQIw-1; Mon, 01 Feb 2021 02:35:30 -0500 X-MC-Unique: O7QH08jgPK6rXsyzh-FQIw-1 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id E113E10054FF; Mon, 1 Feb 2021 07:35:26 +0000 (UTC) Received: from [10.36.113.43] (ovpn-113-43.ams2.redhat.com [10.36.113.43]) by smtp.corp.redhat.com (Postfix) with ESMTPS id C16335F705; Mon, 1 Feb 2021 07:35:20 +0000 (UTC) Subject: Re: [PATCH v12 03/10] iommu: Separate IOMMU_DEV_FEAT_IOPF from IOMMU_DEV_FEAT_SVA To: Jean-Philippe Brucker , joro@8bytes.org, will@kernel.org Cc: lorenzo.pieralisi@arm.com, robh+dt@kernel.org, guohanjun@huawei.com, sudeep.holla@arm.com, rjw@rjwysocki.net, lenb@kernel.org, robin.murphy@arm.com, Jonathan.Cameron@huawei.com, iommu@lists.linux-foundation.org, devicetree@vger.kernel.org, linux-acpi@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-accelerators@lists.ozlabs.org, baolu.lu@linux.intel.com, jacob.jun.pan@linux.intel.com, kevin.tian@intel.com, vdumpa@nvidia.com, zhangfei.gao@linaro.org, shameerali.kolothum.thodi@huawei.com, vivek.gautam@arm.com, Arnd Bergmann , David Woodhouse , Greg Kroah-Hartman , Zhou Wang References: <20210127154322.3959196-1-jean-philippe@linaro.org> <20210127154322.3959196-4-jean-philippe@linaro.org> From: Auger Eric Message-ID: Date: Mon, 1 Feb 2021 08:35:18 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <20210127154322.3959196-4-jean-philippe@linaro.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hi Jean, On 1/27/21 4:43 PM, Jean-Philippe Brucker wrote: > Some devices manage I/O Page Faults (IOPF) themselves instead of relying > on PCIe PRI or Arm SMMU stall. Allow their drivers to enable SVA without > mandating IOMMU-managed IOPF. The other device drivers now need to first > enable IOMMU_DEV_FEAT_IOPF before enabling IOMMU_DEV_FEAT_SVA. Enabling > IOMMU_DEV_FEAT_IOPF on its own doesn't have any effect visible to the > device driver, it is used in combination with other features. > > Signed-off-by: Jean-Philippe Brucker Reviewed-by: Eric Auger Eric > --- > Cc: Arnd Bergmann > Cc: David Woodhouse > Cc: Greg Kroah-Hartman > Cc: Joerg Roedel > Cc: Lu Baolu > Cc: Will Deacon > Cc: Zhangfei Gao > Cc: Zhou Wang > --- > include/linux/iommu.h | 20 +++++++++++++++++--- > 1 file changed, 17 insertions(+), 3 deletions(-) > > diff --git a/include/linux/iommu.h b/include/linux/iommu.h > index b7ea11fc1a93..00348e4c3c26 100644 > --- a/include/linux/iommu.h > +++ b/include/linux/iommu.h > @@ -156,10 +156,24 @@ struct iommu_resv_region { > enum iommu_resv_type type; > }; > > -/* Per device IOMMU features */ > +/** > + * enum iommu_dev_features - Per device IOMMU features > + * @IOMMU_DEV_FEAT_AUX: Auxiliary domain feature > + * @IOMMU_DEV_FEAT_SVA: Shared Virtual Addresses > + * @IOMMU_DEV_FEAT_IOPF: I/O Page Faults such as PRI or Stall. Generally > + * enabling %IOMMU_DEV_FEAT_SVA requires > + * %IOMMU_DEV_FEAT_IOPF, but some devices manage I/O Page > + * Faults themselves instead of relying on the IOMMU. When > + * supported, this feature must be enabled before and > + * disabled after %IOMMU_DEV_FEAT_SVA. > + * > + * Device drivers query whether a feature is supported using > + * iommu_dev_has_feature(), and enable it using iommu_dev_enable_feature(). > + */ > enum iommu_dev_features { > - IOMMU_DEV_FEAT_AUX, /* Aux-domain feature */ > - IOMMU_DEV_FEAT_SVA, /* Shared Virtual Addresses */ > + IOMMU_DEV_FEAT_AUX, > + IOMMU_DEV_FEAT_SVA, > + IOMMU_DEV_FEAT_IOPF, > }; > > #define IOMMU_PASID_INVALID (-1U) >