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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /Documentation/devicetree/bindings/virtio/mmio.txt
parentInitial commit. (diff)
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Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+* virtio memory mapped device
+
+See https://ozlabs.org/~rusty/virtio-spec/ for more details.
+
+Required properties:
+
+- compatible: "virtio,mmio" compatibility string
+- 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: 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