1Linux and the Device Tree
   3The Linux usage model for device tree data
   5Author: Grant Likely <>
   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
  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
  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.
  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
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