mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 01:10:04 +00:00
![Randy Dunlap](/assets/img/avatar_default.png)
Fix (fatal error) s390 docbook file to handle renamed header files. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> cc: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
161 lines
5.4 KiB
XML
161 lines
5.4 KiB
XML
<?xml version="1.0" encoding="UTF-8"?>
|
|
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.1.2//EN"
|
|
"http://www.oasis-open.org/docbook/xml/4.1.2/docbookx.dtd" []>
|
|
|
|
<book id="s390drivers">
|
|
<bookinfo>
|
|
<title>Writing s390 channel device drivers</title>
|
|
|
|
<authorgroup>
|
|
<author>
|
|
<firstname>Cornelia</firstname>
|
|
<surname>Huck</surname>
|
|
<affiliation>
|
|
<address>
|
|
<email>cornelia.huck@de.ibm.com</email>
|
|
</address>
|
|
</affiliation>
|
|
</author>
|
|
</authorgroup>
|
|
|
|
<copyright>
|
|
<year>2007</year>
|
|
<holder>IBM Corp.</holder>
|
|
</copyright>
|
|
|
|
<legalnotice>
|
|
<para>
|
|
This documentation is free software; you can redistribute
|
|
it and/or modify it under the terms of the GNU General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2 of the License, or (at your option) any later
|
|
version.
|
|
</para>
|
|
|
|
<para>
|
|
This program is distributed in the hope that it will be
|
|
useful, but WITHOUT ANY WARRANTY; without even the implied
|
|
warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
|
|
See the GNU General Public License for more details.
|
|
</para>
|
|
|
|
<para>
|
|
You should have received a copy of the GNU General Public
|
|
License along with this program; if not, write to the Free
|
|
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston,
|
|
MA 02111-1307 USA
|
|
</para>
|
|
|
|
<para>
|
|
For more details see the file COPYING in the source
|
|
distribution of Linux.
|
|
</para>
|
|
</legalnotice>
|
|
</bookinfo>
|
|
|
|
<toc></toc>
|
|
|
|
<chapter id="intro">
|
|
<title>Introduction</title>
|
|
<para>
|
|
This document describes the interfaces available for device drivers that
|
|
drive s390 based channel attached I/O devices. This includes interfaces for
|
|
interaction with the hardware and interfaces for interacting with the
|
|
common driver core. Those interfaces are provided by the s390 common I/O
|
|
layer.
|
|
</para>
|
|
<para>
|
|
The document assumes a familarity with the technical terms associated
|
|
with the s390 channel I/O architecture. For a description of this
|
|
architecture, please refer to the "z/Architecture: Principles of
|
|
Operation", IBM publication no. SA22-7832.
|
|
</para>
|
|
<para>
|
|
While most I/O devices on a s390 system are typically driven through the
|
|
channel I/O mechanism described here, there are various other methods
|
|
(like the diag interface). These are out of the scope of this document.
|
|
</para>
|
|
<para>
|
|
Some additional information can also be found in the kernel source
|
|
under Documentation/s390/driver-model.txt.
|
|
</para>
|
|
</chapter>
|
|
<chapter id="ccw">
|
|
<title>The ccw bus</title>
|
|
<para>
|
|
The ccw bus typically contains the majority of devices available to
|
|
a s390 system. Named after the channel command word (ccw), the basic
|
|
command structure used to address its devices, the ccw bus contains
|
|
so-called channel attached devices. They are addressed via I/O
|
|
subchannels, visible on the css bus. A device driver for
|
|
channel-attached devices, however, will never interact with the
|
|
subchannel directly, but only via the I/O device on the ccw bus,
|
|
the ccw device.
|
|
</para>
|
|
<sect1 id="channelIO">
|
|
<title>I/O functions for channel-attached devices</title>
|
|
<para>
|
|
Some hardware structures have been translated into C structures for use
|
|
by the common I/O layer and device drivers. For more information on
|
|
the hardware structures represented here, please consult the Principles
|
|
of Operation.
|
|
</para>
|
|
!Iarch/s390/include/asm/cio.h
|
|
</sect1>
|
|
<sect1 id="ccwdev">
|
|
<title>ccw devices</title>
|
|
<para>
|
|
Devices that want to initiate channel I/O need to attach to the ccw bus.
|
|
Interaction with the driver core is done via the common I/O layer, which
|
|
provides the abstractions of ccw devices and ccw device drivers.
|
|
</para>
|
|
<para>
|
|
The functions that initiate or terminate channel I/O all act upon a
|
|
ccw device structure. Device drivers must not bypass those functions
|
|
or strange side effects may happen.
|
|
</para>
|
|
!Iarch/s390/include/asm/ccwdev.h
|
|
!Edrivers/s390/cio/device.c
|
|
!Edrivers/s390/cio/device_ops.c
|
|
</sect1>
|
|
<sect1 id="cmf">
|
|
<title>The channel-measurement facility</title>
|
|
<para>
|
|
The channel-measurement facility provides a means to collect
|
|
measurement data which is made available by the channel subsystem
|
|
for each channel attached device.
|
|
</para>
|
|
!Iarch/s390/include/asm/cmb.h
|
|
!Edrivers/s390/cio/cmf.c
|
|
</sect1>
|
|
</chapter>
|
|
|
|
<chapter id="ccwgroup">
|
|
<title>The ccwgroup bus</title>
|
|
<para>
|
|
The ccwgroup bus only contains artificial devices, created by the user.
|
|
Many networking devices (e.g. qeth) are in fact composed of several
|
|
ccw devices (like read, write and data channel for qeth). The
|
|
ccwgroup bus provides a mechanism to create a meta-device which
|
|
contains those ccw devices as slave devices and can be associated
|
|
with the netdevice.
|
|
</para>
|
|
<sect1 id="ccwgroupdevices">
|
|
<title>ccw group devices</title>
|
|
!Iarch/s390/include/asm/ccwgroup.h
|
|
!Edrivers/s390/cio/ccwgroup.c
|
|
</sect1>
|
|
</chapter>
|
|
|
|
<chapter id="genericinterfaces">
|
|
<title>Generic interfaces</title>
|
|
<para>
|
|
Some interfaces are available to other drivers that do not necessarily
|
|
have anything to do with the busses described above, but still are
|
|
indirectly using basic infrastructure in the common I/O layer.
|
|
One example is the support for adapter interrupts.
|
|
</para>
|
|
!Edrivers/s390/cio/airq.c
|
|
</chapter>
|
|
|
|
</book>
|