Linux-Architecture-Reference/DeviceTree/ch_introduction.xml

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<chapter xmlns="http://docbook.org/ns/docbook" 
         xmlns:xi="http://www.w3.org/2001/XInclude"
         xmlns:xlink="http://www.w3.org/1999/xlink" 
         version="5.0"
         xml:id="ch_introduction">
         
  <title>Introduction</title>
  
    <para>This document specifies the application of OF to an LoPAR System,
    including requirements and practices to support unique hardware and
    firmware specific to the platform implementation. The core requirements and
    practices specified by OF must be augmented by system-specific requirements
    to form a complete specification for the firmware implementation of an
    LoPAR System. This appendix establishes such additional requirements
    pertaining to the platform and the support required by OF.</para>
    
    <para>This document also specifies the application of OF to a PA Processor
    (which covers all PowerPC processors and their successors), including
    requirements and practices to support unique firmware specific to a PA
    Processor. The core requirements and practices specified by OF must be
    augmented by processor-specific requirements to form a complete
    specification for the firmware implementation for a PA processor.
    <xref linkend="dbdoclet.50569374_59715" />
    establishes such additional requirements pertaining to the
    processor and the support required by OF.</para>

    <para>This document further specifies the application of 
    <emphasis>IEEE Std 1275-1994 Standard for Boot (Initialization,
    Configuration) Firmware, Core Practices and Requirements</emphasis>, 
    <emphasis>Core Errata, IEEE P1275.7</emphasis> and appropriate OF Standards
    for LoPAR computer systems, including practices for client program
    interface and data formats.</para>
        
    <section>
      <title>General Requirements</title>
      <para>An OF implementation for an LoPAR platform shall implement the
      core requirements as defined in 
      <xref linkend="dbdoclet.50569387_45524" />, core errata 
      <xref linkend="dbdoclet.50569387_14175" />, the PA Processor-specific
      extensions described in 
      <xref linkend="dbdoclet.50569374_59715" />, other appropriate bindings
      and/or recommended practices contained in the references (see 
      <xref linkend="dbdoclet.50569387_27251" />), and the LoPAR Binding
      specific extensions described in this appendix.</para>
      <para>In addition, an OF implementation for an LoPAR platform shall
      implement the 
      <emphasis>Device Interface</emphasis>, 
      <emphasis>Client Interface</emphasis> and 
      <emphasis>User Interface</emphasis> as defined in 
      <xref linkend="dbdoclet.50569387_45524" />.</para>
      <para>Some LoPAR Binding property names exceed the OF Base specification
      limit of 31 characters. LoPAR OF implementations shall support property
      names of at least 47 characters.</para>
      
    </section>
    
    <section>
      <title>Processor Architecture Requirements</title>

      <para><xref linkend="dbdoclet.50569374_59715" /> specifies the application of 
      <emphasis>
        <xref linkend="dbdoclet.50569387_45524" />
      </emphasis> to computer systems that use the PA instruction set, including
      instruction-set-specific requirements and practices for debugging, client
      program interface and data formats. An implementation of OF for PA shall
      implement the core requirements as defined in 
      <xref linkend="dbdoclet.50569387_45524" />and the PA-specific extensions
      described in this binding.</para>
      <para>This appendix addresses 
      <xref linkend="dbdoclet.50569387_99718" />. The descriptions that follow,
      and the relevant sections describing translation features for this binding,
      assume that the system&#8217;s PA processor(s) implement the entire PA
      (that is, all books of 
      <xref linkend="dbdoclet.50569387_99718" />). Some processors may implement
      different Book II-III features; such processors may need a variant of this
      binding describing the differences to the mapping functions, etc.</para>
      
    </section>
  
</chapter>