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authorStefano Stabellini <stefanos@xilinx.com>2018-12-03 23:26:09 +0100
committerRob Herring <robh@kernel.org>2018-12-10 22:35:51 +0100
commit27b4feb7fe373e1ed92b9362b1e33cead271ac84 (patch)
treebd1bc42c76e11be02b0860b120c860f4e0ff2e6a /Documentation/devicetree/bindings/reserved-memory
parentof: Use of_node_name_eq for node name comparisons (diff)
downloadlinux-27b4feb7fe373e1ed92b9362b1e33cead271ac84.tar.xz
linux-27b4feb7fe373e1ed92b9362b1e33cead271ac84.zip
devicetree,xen: add xen,shared-memory binding
Introduce a device tree binding for Xen reserved-memory regions. They are used to share memory across VMs from the VM config files. (See static_shm config option.) Signed-off-by: Stefano Stabellini <stefanos@xilinx.com> Cc: julien.grall@arm.com Cc: devicetree@vger.kernel.org Cc: robh+dt@kernel.org Cc: mark.rutland@arm.com Cc: xen-devel@lists.xen.org Signed-off-by: Rob Herring <robh@kernel.org>
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+* Xen hypervisor reserved-memory binding
+
+Expose one or more memory regions as reserved-memory to the guest
+virtual machine. Typically, a region is configured at VM creation time
+to be a shared memory area across multiple virtual machines for
+communication among them.
+
+For each of these pre-shared memory regions, a range is exposed under
+the /reserved-memory node as a child node. Each range sub-node is named
+xen-shmem@<address> and has the following properties:
+
+- compatible:
+ compatible = "xen,shared-memory-v1"
+
+- reg:
+ the base guest physical address and size of the shared memory region
+
+- xen,offset: (borrower VMs only)
+ 64 bit integer offset within the owner virtual machine's shared
+ memory region used for the mapping in the borrower VM.
+
+- xen,id:
+ a string that identifies the shared memory region as specified in
+ the VM config file