From patchwork Fri Oct 12 14:59:11 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Philippe Brucker X-Patchwork-Id: 983119 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=devicetree-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 42Wrcd5lKKz9s4Z for ; Sat, 13 Oct 2018 02:00:49 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728852AbeJLWdk (ORCPT ); Fri, 12 Oct 2018 18:33:40 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:52676 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728182AbeJLWdj (ORCPT ); Fri, 12 Oct 2018 18:33:39 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id A785A1596; Fri, 12 Oct 2018 08:00:48 -0700 (PDT) Received: from ostrya.cambridge.arm.com (ostrya.cambridge.arm.com [10.1.196.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id B7C5F3F5BC; Fri, 12 Oct 2018 08:00:45 -0700 (PDT) From: Jean-Philippe Brucker To: iommu@lists.linux-foundation.org, virtualization@lists.linux-foundation.org, devicetree@vger.kernel.org Cc: linux-pci@vger.kernel.org, kvmarm@lists.cs.columbia.edu, peter.maydell@linaro.org, joro@8bytes.org, mst@redhat.com, jasowang@redhat.com, robh+dt@kernel.org, mark.rutland@arm.com, eric.auger@redhat.com, tnowicki@caviumnetworks.com, kevin.tian@intel.com, marc.zyngier@arm.com, robin.murphy@arm.com, will.deacon@arm.com, lorenzo.pieralisi@arm.com Subject: [PATCH v3 1/7] dt-bindings: virtio-mmio: Add IOMMU description Date: Fri, 12 Oct 2018 15:59:11 +0100 Message-Id: <20181012145917.6840-2-jean-philippe.brucker@arm.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181012145917.6840-1-jean-philippe.brucker@arm.com> References: <20181012145917.6840-1-jean-philippe.brucker@arm.com> MIME-Version: 1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org The nature of a virtio-mmio node is discovered by the virtio driver at probe time. However the DMA relation between devices must be described statically. When a virtio-mmio node is a virtio-iommu device, it needs an "#iommu-cells" property as specified by bindings/iommu/iommu.txt. Otherwise, the virtio-mmio device may perform DMA through an IOMMU, which requires an "iommus" property. Describe these requirements in the device-tree bindings documentation. Signed-off-by: Jean-Philippe Brucker Reviewed-by: Rob Herring Reviewed-by: Eric Auger --- .../devicetree/bindings/virtio/mmio.txt | 30 +++++++++++++++++++ 1 file changed, 30 insertions(+) diff --git a/Documentation/devicetree/bindings/virtio/mmio.txt b/Documentation/devicetree/bindings/virtio/mmio.txt index 5069c1b8e193..748595473b36 100644 --- a/Documentation/devicetree/bindings/virtio/mmio.txt +++ b/Documentation/devicetree/bindings/virtio/mmio.txt @@ -8,10 +8,40 @@ Required properties: - reg: control registers base address and size including configuration space - interrupts: interrupt generated by the device +Required properties for virtio-iommu: + +- #iommu-cells: When the node corresponds to a virtio-iommu device, it is + linked to DMA masters using the "iommus" or "iommu-map" + properties [1][2]. #iommu-cells specifies the size of the + "iommus" property. For virtio-iommu #iommu-cells must be + 1, each cell describing a single endpoint ID. + +Optional properties: + +- iommus: If the device accesses memory through an IOMMU, it should + have an "iommus" property [1]. Since virtio-iommu itself + does not access memory through an IOMMU, the "virtio,mmio" + node cannot have both an "#iommu-cells" and an "iommus" + property. + Example: virtio_block@3000 { compatible = "virtio,mmio"; reg = <0x3000 0x100>; interrupts = <41>; + + /* Device has endpoint ID 23 */ + iommus = <&viommu 23> } + + viommu: virtio_iommu@3100 { + compatible = "virtio,mmio"; + reg = <0x3100 0x100>; + interrupts = <42>; + + #iommu-cells = <1> + } + +[1] Documentation/devicetree/bindings/iommu/iommu.txt +[2] Documentation/devicetree/bindings/pci/pci-iommu.txt From patchwork Fri Oct 12 14:59:12 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jean-Philippe Brucker X-Patchwork-Id: 983121 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=devicetree-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=arm.com Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 42Wrcj0s5Hz9s3Z for ; Sat, 13 Oct 2018 02:00:53 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728720AbeJLWdn (ORCPT ); Fri, 12 Oct 2018 18:33:43 -0400 Received: from usa-sjc-mx-foss1.foss.arm.com ([217.140.101.70]:52692 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728182AbeJLWdn (ORCPT ); Fri, 12 Oct 2018 18:33:43 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id D573BF; Fri, 12 Oct 2018 08:00:51 -0700 (PDT) Received: from ostrya.cambridge.arm.com (ostrya.cambridge.arm.com [10.1.196.78]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id E4DEE3F5BC; Fri, 12 Oct 2018 08:00:48 -0700 (PDT) From: Jean-Philippe Brucker To: iommu@lists.linux-foundation.org, virtualization@lists.linux-foundation.org, devicetree@vger.kernel.org Cc: linux-pci@vger.kernel.org, kvmarm@lists.cs.columbia.edu, peter.maydell@linaro.org, joro@8bytes.org, mst@redhat.com, jasowang@redhat.com, robh+dt@kernel.org, mark.rutland@arm.com, eric.auger@redhat.com, tnowicki@caviumnetworks.com, kevin.tian@intel.com, marc.zyngier@arm.com, robin.murphy@arm.com, will.deacon@arm.com, lorenzo.pieralisi@arm.com Subject: [PATCH v3 2/7] dt-bindings: virtio: Add virtio-pci-iommu node Date: Fri, 12 Oct 2018 15:59:12 +0100 Message-Id: <20181012145917.6840-3-jean-philippe.brucker@arm.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181012145917.6840-1-jean-philippe.brucker@arm.com> References: <20181012145917.6840-1-jean-philippe.brucker@arm.com> MIME-Version: 1.0 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Some systems implement virtio-iommu as a PCI endpoint. The operating systems needs to discover the relationship between IOMMU and masters long before the PCI endpoint gets probed. Add a PCI child node to describe the virtio-iommu device. The virtio-pci-iommu is conceptually split between a PCI programming interface and a translation component on the parent bus. The latter doesn't have a node in the device tree. The virtio-pci-iommu node describes both, by linking the PCI endpoint to "iommus" property of DMA master nodes and to "iommu-map" properties of bus nodes. Signed-off-by: Jean-Philippe Brucker Reviewed-by: Rob Herring Reviewed-by: Eric Auger --- .../devicetree/bindings/virtio/iommu.txt | 66 +++++++++++++++++++ 1 file changed, 66 insertions(+) create mode 100644 Documentation/devicetree/bindings/virtio/iommu.txt diff --git a/Documentation/devicetree/bindings/virtio/iommu.txt b/Documentation/devicetree/bindings/virtio/iommu.txt new file mode 100644 index 000000000000..2407fea0651c --- /dev/null +++ b/Documentation/devicetree/bindings/virtio/iommu.txt @@ -0,0 +1,66 @@ +* virtio IOMMU PCI device + +When virtio-iommu uses the PCI transport, its programming interface is +discovered dynamically by the PCI probing infrastructure. However the +device tree statically describes the relation between IOMMU and DMA +masters. Therefore, the PCI root complex that hosts the virtio-iommu +contains a child node representing the IOMMU device explicitly. + +Required properties: + +- compatible: Should be "virtio,pci-iommu" +- reg: PCI address of the IOMMU. As defined in the PCI Bus + Binding reference [1], the reg property is a five-cell + address encoded as (phys.hi phys.mid phys.lo size.hi + size.lo). phys.hi should contain the device's BDF as + 0b00000000 bbbbbbbb dddddfff 00000000. The other cells + should be zero. +- #iommu-cells: Each platform DMA master managed by the IOMMU is assigned + an endpoint ID, described by the "iommus" property [2]. + For virtio-iommu, #iommu-cells must be 1. + +Notes: + +- DMA from the IOMMU device isn't managed by another IOMMU. Therefore the + virtio-iommu node doesn't have an "iommus" property, and is omitted from + the iommu-map property of the root complex. + +Example: + +pcie@10000000 { + compatible = "pci-host-ecam-generic"; + ... + + /* The IOMMU programming interface uses slot 00:01.0 */ + iommu0: iommu@0008 { + compatible = "virtio,pci-iommu"; + reg = <0x00000800 0 0 0 0>; + #iommu-cells = <1>; + }; + + /* + * The IOMMU manages all functions in this PCI domain except + * itself. Omit BDF 00:01.0. + */ + iommu-map = <0x0 &iommu0 0x0 0x8> + <0x9 &iommu0 0x9 0xfff7>; +}; + +pcie@20000000 { + compatible = "pci-host-ecam-generic"; + ... + /* + * The IOMMU also manages all functions from this domain, + * with endpoint IDs 0x10000 - 0x1ffff + */ + iommu-map = <0x0 &iommu0 0x10000 0x10000>; +}; + +ethernet@fe001000 { + ... + /* The IOMMU manages this platform device with endpoint ID 0x20000 */ + iommus = <&iommu0 0x20000>; +}; + +[1] Documentation/devicetree/bindings/pci/pci.txt +[2] Documentation/devicetree/bindings/iommu/iommu.txt