Linux-Architecture-Reference/LoPAR/sec_rtas_hot_plug.xml

<?xml version="1.0" encoding="UTF-8"?>
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<section 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="Hot_Plug_Events">

  <title>Hot Plug Events</title>

  <para>Hot Plug Events, when implemented, are reported through
  either the event-scan RTAS call or a hotplug interrupt.</para>

  <para>An OS that wants to be notified of hotplug events will need to
  set the appropriate arch-vector bit.  Look for the hot-plug-events
  node in the /event-sources node of the OF device tree (see
  <xref linkend="sec_papr_bindings_hot_plug_events" />), enable the interrupts listed
  in its “interrupts” property and provide an interrupt handler to call
  check-exception when one of those interrupts are received.</para>

  <para>When a hotplug event occurs, whether reported by check-exception
  or event-scan, RTAS will directly pass back the Hotplug Event Log as
  described in <xref linkend="table.error.hotplug" />.</para>

  <variablelist>

  	<varlistentry>
  		<term><emphasis role="bold">R1-<xref linkend="Hot_Plug_Events"
			xrefstyle="select: labelnumber nopage"/>-1.</emphasis></term>
  			<listitem>
		      <para>If FRUs can be hot plugged in the system
		      without OS support, the Hot Plug Event mechanism must be provided for
		      signaling the OS about the event.</para>
  			</listitem>
  	</varlistentry>

  </variablelist>

</section>