From nobody Wed Feb 11 16:22:42 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id D1B55C77B75 for ; Sat, 6 May 2023 13:27:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232449AbjEFN1f (ORCPT ); Sat, 6 May 2023 09:27:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49712 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232401AbjEFN1O (ORCPT ); Sat, 6 May 2023 09:27:14 -0400 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6818A1C0F2 for ; Sat, 6 May 2023 06:27:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1683379633; x=1714915633; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=6kF0WZAR4rQ0vQdOZz3ojMQj9WSdjbV+mkgN/IGSPOs=; b=QSwG1OR7tnBsDAcJo1g9A1qy+RNcyfrNpzdIpIC1+ZhXF/bwnGH251Zw gWq5CA3uCjgNyfPPkTaxqXkS8+svfevcgZ7C84LsBSox1rBkS1+vU4ztm ENQj3VqzFGedrOPeh2mQAD055nD6hXHDeWGcy70shluyTemRpcjS2hDCI ztuOe/UvbRe8VVKp/zD1gRHR/P3KIUNmcxjwV9BCUfZ6vOv0OjVmOjF4X UWgBdOND9vPmqHiysWwPxvD+gkJaKVnpkH+boc/HAuY7nkjzEim5F6zsi E2aDuwfYm5L+PeejO1znL4Rqrz/1QyPJTagKaQ920uiUfI3lP0+hymFwi Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10702"; a="412631141" X-IronPort-AV: E=Sophos;i="5.99,255,1677571200"; d="scan'208";a="412631141" Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 06 May 2023 06:27:13 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10702"; a="944265958" X-IronPort-AV: E=Sophos;i="5.99,255,1677571200"; d="scan'208";a="944265958" Received: from srinivas-otcpl-7600.jf.intel.com (HELO jacob-builder.jf.intel.com) ([10.54.97.184]) by fmsmga006.fm.intel.com with ESMTP; 06 May 2023 06:27:12 -0700 From: Jacob Pan To: LKML , iommu@lists.linux.dev, Jason Gunthorpe , "Lu Baolu" , Joerg Roedel , Jean-Philippe Brucker , "Robin Murphy" Cc: "Will Deacon" , Raj Ashok , "Tian, Kevin" , Yi Liu , "Yu, Fenghua" , torvalds@linux-foundation.org, Jacob Pan Subject: [PATCH] iommu: Add Kconfig help text for IOMMU_SVA Date: Sat, 6 May 2023 06:31:34 -0700 Message-Id: <20230506133134.1492395-1-jacob.jun.pan@linux.intel.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Shared Virtual Addressing (SVA) is not immediately intuitive to people who work outside IOMMU subsystem, add some explanation to make it less opaque. Link: https://lore.kernel.org/lkml/ZE70doFi8X3KgfrV@ziepe.ca/t/#meaa938c918= 57665b376db59e16b532ba9d4ea013 Signed-off-by: Jacob Pan --- drivers/iommu/Kconfig | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/Kconfig b/drivers/iommu/Kconfig index db98c3f86e8c..0f7181007dc1 100644 --- a/drivers/iommu/Kconfig +++ b/drivers/iommu/Kconfig @@ -1,4 +1,4 @@ -# SPDX-License-Identifier: GPL-2.0-only +# PDX-License-Identifier: GPL-2.0-only # The IOVA library may also be used by non-IOMMU_API users config IOMMU_IOVA tristate @@ -155,7 +155,14 @@ config IOMMU_DMA =20 # Shared Virtual Addressing config IOMMU_SVA - bool + bool "Shared Virtual Addressing" + help + IOMMU and CPU share page tables for user processes thus DMA can use + CPU virtual address. Under intel architecture, it is also called + Shared Virtual Memory (SVM). + With SVA, DMA requests are tagged with PCIe Process Address Space ID + (PASID) or Substream ID (ARM SMMU term) with which page tables are + associated. =20 config FSL_PAMU bool "Freescale IOMMU support" --=20 2.25.1