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What:		/sys/firmware/devicetree/*
Date:		November 2013
Contact:	Grant Likely <grant.likely@linaro.org>
Description:
		When using OpenFirmware or a Flattened Device Tree to enumerate
		hardware, the device tree structure will be exposed in this
		directory.

		It is possible for multiple device-tree directories to exist.
		Some device drivers use a separate detached device tree which
		have no attachment to the system tree and will appear in a
		different subdirectory under /sys/firmware/devicetree.

		Userspace must not use the /sys/firmware/devicetree/base
		path directly, but instead should follow /proc/device-tree
		symlink. It is possible that the absolute path will change
		in the future, but the symlink is the stable ABI.

		The /proc/device-tree symlink replaces the devicetree /proc
		filesystem support, and has largely the same semantics and
		should be compatible with existing userspace.

		The contents of /sys/firmware/devicetree/ is a
		hierarchy of directories, one per device tree node. The
		directory name is the resolved path component name (node
		name plus address). Properties are represented as files
		in the directory. The contents of each file is the exact
		binary data from the device tree.