linux/Documentation/devicetree/usage-model.txt
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   1Linux and the Device Tree
   2-------------------------
   3The Linux usage model for device tree data
   4
   5Author: Grant Likely <grant.likely@secretlab.ca>
   6
   7This article describes how Linux uses the device tree.  An overview of
   8the device tree data format can be found on the device tree usage page
   9at devicetree.org[1].
  10
  11[1] http://devicetree.org/Device_Tree_Usage
  12
  13The "Open Firmware Device Tree", or simply Device Tree (DT), is a data
  14structure and language for describing hardware.  More specifically, it
  15is a description of hardware that is readable by an operating system
  16so that the operating system doesn't need to hard code details of the
  17machine.
  18
  19Structurally, the DT is a tree, or acyclic graph with named nodes, and
  20nodes may have an arbitrary number of named properties encapsulating
  21arbitrary data.  A mechanism also exists to create arbitrary
  22links from one node to another outside of the natural tree structure.
  23
  24Conceptually, a common set of usage conventions, called 'bindings',
  25is defined for how data should appear in the tree to describe typical
  26hardware characteristics including data busses, interrupt lines, GPIO
  1
  
  
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