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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 483ECC433FE for ; Mon, 30 May 2022 21:01:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S243265AbiE3VBD (ORCPT ); Mon, 30 May 2022 17:01:03 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40194 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243223AbiE3VAf (ORCPT ); Mon, 30 May 2022 17:00:35 -0400 Received: from mail-lj1-x230.google.com (mail-lj1-x230.google.com [IPv6:2a00:1450:4864:20::230]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 027339156C; Mon, 30 May 2022 14:00:32 -0700 (PDT) Received: by mail-lj1-x230.google.com with SMTP id s13so981058ljd.4; Mon, 30 May 2022 14:00:32 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=+FJSf1vwMYB6K1+IygWHYLgdHKsQ/Ri86qwFQ7er7r4=; b=qQaEnEqIn8+KVCu3pPRo+BDQrdzTpsLMqbypvWjSdP/zBsAUHoF+Gerr5XT7DNRZW1 0bpkwfkPu1hMKNckTJkbfqyHKTvvxPuLi2IZmXv8DMFMNKXEOakkweh7lNNBTtPOBInP RK0XWq87slLWTrLyJGGcQJqd8OW+B3LmN9XSCB6PL+8FmxkWI4gWNWUhuz5hn/0OLywc FmS2FjqsGyViA9Q3hUbKnJx84AOsuqZKFmqJuUPb+jKs+WQqtD/joiFjLBoJ8UGFL5xq t9Y57ac2D/yaMy2ErqyyoxRbxwDkBaU13uHKzvKFZmAcaFPptLb+oQOVf2CD+OnQqqDE qNHA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=+FJSf1vwMYB6K1+IygWHYLgdHKsQ/Ri86qwFQ7er7r4=; b=BIRChedqMtG6xMp0pZRoqcp1BP1PbBucY7g6yndesc88p1xSmPYh4eOjEe4m5MkLO3 oOLRxIjCTM7vJUQA6pJymIOkLNIKwhr6sIhxj7xQjAq3+jwazG+D2RHL0D1lliN1MBNM +PayFrAQVSsoh3zL2xTGIF8enfOL0z9YAgWTpvuQkwLlApCrRnhkbtlICNcGRLYz2z+L 8YmMnok5bhtxwGDNBIrBkY5COeiHdKN5Qod+7kC8co8uSFIXBSbrzjG0IBZQIH6gU+h/ tp6mmBDjJjU9ERVTv4u0AslfNTau897eDJGvam4dZQJTJoFpkfbSwDkhWV0kL6QpjtMP O7KA== X-Gm-Message-State: AOAM533MwhsoxRrIyy/rTL7yGxt8vhtECfXuFbDCDghb5nZ6yQtmsaiF O67p8mnkVA0SPxc1uS7vAh4= X-Google-Smtp-Source: ABdhPJy1j0CZ8u38C6o5Ly2O9aBU8Z/J0PR4IPWipSyv2hmVKkIJPggqQZ4sM6kw/XDqJU3SD8VYcQ== X-Received: by 2002:a2e:a36f:0:b0:253:d948:731c with SMTP id i15-20020a2ea36f000000b00253d948731cmr32005387ljn.159.1653944431239; Mon, 30 May 2022 14:00:31 -0700 (PDT) Received: from otyshchenko.router ([212.22.223.21]) by smtp.gmail.com with ESMTPSA id k21-20020a2ea275000000b0025550e2693asm581541ljm.38.2022.05.30.14.00.30 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Mon, 30 May 2022 14:00:30 -0700 (PDT) From: Oleksandr Tyshchenko To: xen-devel@lists.xenproject.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, iommu@lists.linux-foundation.org Cc: Oleksandr Tyshchenko , Rob Herring , Joerg Roedel , Will Deacon , Krzysztof Kozlowski , Julien Grall , Juergen Gross , Stefano Stabellini , "Michael S. Tsirkin" , Christoph Hellwig , Arnd Bergmann Subject: [PATCH V3 5/8] dt-bindings: Add xen,grant-dma IOMMU description for xen-grant DMA ops Date: Tue, 31 May 2022 00:00:14 +0300 Message-Id: <1653944417-17168-6-git-send-email-olekstysh@gmail.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1653944417-17168-1-git-send-email-olekstysh@gmail.com> References: <1653944417-17168-1-git-send-email-olekstysh@gmail.com> Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org From: Oleksandr Tyshchenko The main purpose of this binding is to communicate Xen specific information using generic IOMMU device tree bindings (which is a good fit here) rather than introducing a custom property. Introduce Xen specific IOMMU for the virtualized device (e.g. virtio) to be used by Xen grant DMA-mapping layer in the subsequent commit. The reference to Xen specific IOMMU node using "iommus" property indicates that Xen grant mappings need to be enabled for the device, and it specifies the ID of the domain where the corresponding backend resides. The domid (domain ID) is used as an argument to the Xen grant mapping APIs. This is needed for the option to restrict memory access using Xen grant mappings to work which primary goal is to enable using virtio devices in Xen guests. Signed-off-by: Oleksandr Tyshchenko --- Changes RFC -> V1: - update commit subject/description and text in description - move to devicetree/bindings/arm/ Changes V1 -> V2: - update text in description - change the maintainer of the binding - fix validation issue - reference xen,dev-domid.yaml schema from virtio/mmio.yaml Change V2 -> V3: - Stefano already gave his Reviewed-by, I dropped it due to the changes (significant) - use generic IOMMU device tree bindings instead of custom property "xen,dev-domid" - change commit subject and description, was "dt-bindings: Add xen,dev-domid property description for xen-grant DMA ops" --- .../devicetree/bindings/iommu/xen,grant-dma.yaml | 49 ++++++++++++++++++++++ 1 file changed, 49 insertions(+) create mode 100644 Documentation/devicetree/bindings/iommu/xen,grant-dma.yaml diff --git a/Documentation/devicetree/bindings/iommu/xen,grant-dma.yaml b/Documentation/devicetree/bindings/iommu/xen,grant-dma.yaml new file mode 100644 index 00000000..ab5765c --- /dev/null +++ b/Documentation/devicetree/bindings/iommu/xen,grant-dma.yaml @@ -0,0 +1,49 @@ +# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/iommu/xen,grant-dma.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Xen specific IOMMU for virtualized devices (e.g. virtio) + +maintainers: + - Stefano Stabellini + +description: + The reference to Xen specific IOMMU node using "iommus" property indicates + that Xen grant mappings need to be enabled for the device, and it specifies + the ID of the domain where the corresponding backend resides. + The binding is required to restrict memory access using Xen grant mappings. + +properties: + compatible: + const: xen,grant-dma + + '#iommu-cells': + const: 1 + description: + Xen specific IOMMU is multiple-master IOMMU device. + The single cell describes the domid (domain ID) of the domain where + the backend is running. + +required: + - compatible + - "#iommu-cells" + +additionalProperties: false + +examples: + - | + xen_iommu { + compatible = "xen,grant-dma"; + #iommu-cells = <1>; + }; + + virtio@3000 { + compatible = "virtio,mmio"; + reg = <0x3000 0x100>; + interrupts = <41>; + + /* The backend is located in Xen domain with ID 1 */ + iommus = <&xen_iommu 1>; + }; -- 2.7.4