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Give a better bus address example than 0x23c, since most ISA devices

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map to 8 or 16 byte boundaries.  Use 0x230 instead.  Remove part of a
bullet item about documenting each device_t field here because a
device_t is supposed to be an opaque data structure to the client
drivers.
This commit is contained in:
Warner Losh 2002-09-08 22:08:56 +00:00
parent dd540ae7ec
commit 5dc1ae8669
Notes: svn2git 2020-12-08 03:00:23 +00:00 
svn path=/head/; revision=14215
2 changed files with 8 additions and 10 deletions
en_US.ISO8859-1/books
arch-handbook/newbus
chapter.sgml
developers-handbook/newbus
chapter.sgml

9
en_US.ISO8859-1/books/arch-handbook/newbus/chapter.sgml
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@ -9,8 +9,7 @@
Future Additions:
o Expand the information about device_t, and explain each and
every field in it.
o Expand the information about device_t
o Add information about the bus_* functions.
o Add information about bus specific (e.g. PCI) functions.
o Add a reference section for additional information.
@ -148,12 +147,12 @@
which knows about all resources.</para>
<tip><para>An ISA device might want to map its IO port at
<literal>0x23c</literal>, so it asks its parent, in this case the ISA
<literal>0x230</literal>, so it asks its parent, in this case the ISA
bus. The ISA bus hands it over to the PCI-to-ISA bridge which in its turn
asks the PCI bus, which reaches the host-to-PCI bridge and finally the
nexus. The beauty of this transition upwards is that there is room to
translate the requests. For example, the <literal>0x23c</literal> IO port
request might become memory-mapped at <literal>0xb000023c</literal> on a
translate the requests. For example, the <literal>0x230</literal> IO port
request might become memory-mapped at <literal>0xb0000230</literal> on a
<acronym>MIPS</acronym> box by the PCI bridge.</para></tip>
<para>Resource allocation can be controlled at any place in the device

9
en_US.ISO8859-1/books/developers-handbook/newbus/chapter.sgml
View file

@ -9,8 +9,7 @@
Future Additions:
o Expand the information about device_t, and explain each and
every field in it.
o Expand the information about device_t
o Add information about the bus_* functions.
o Add information about bus specific (e.g. PCI) functions.
o Add a reference section for additional information.
@ -148,12 +147,12 @@
which knows about all resources.</para>
<tip><para>An ISA device might want to map its IO port at
<literal>0x23c</literal>, so it asks its parent, in this case the ISA
<literal>0x230</literal>, so it asks its parent, in this case the ISA
bus. The ISA bus hands it over to the PCI-to-ISA bridge which in its turn
asks the PCI bus, which reaches the host-to-PCI bridge and finally the
nexus. The beauty of this transition upwards is that there is room to
translate the requests. For example, the <literal>0x23c</literal> IO port
request might become memory-mapped at <literal>0xb000023c</literal> on a
translate the requests. For example, the <literal>0x230</literal> IO port
request might become memory-mapped at <literal>0xb0000230</literal> on a
<acronym>MIPS</acronym> box by the PCI bridge.</para></tip>
<para>Resource allocation can be controlled at any place in the device