1238 lines
44 KiB
Plaintext
1238 lines
44 KiB
Plaintext
<!-- $Id: kernelconfig.sgml,v 1.4 1995/12/04 17:58:41 jfieber Exp $ -->
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<!-- The FreeBSD Documentation Project -->
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<!-- <!DOCTYPE linuxdoc PUBLIC '-//FreeBSD//DTD linuxdoc//EN'> -->
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<chapt><heading>Configuring the FreeBSD Kernel<label id="kernelconfig"></heading>
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<p><em>Contributed by &a.jehamby;.<newline>6 October 1995.</em>
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This large section of the handbook discusses the basics of
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building your own custom kernel for FreeBSD. This section
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is appropriate for both novice system administrators and
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those with advanced Unix experience.
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<sect><heading>Why build a custom kernel?</heading>
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<p>Building a custom kernel is one of the most important
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rites of passage every Unix system administrator must
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learn. This process, while time-consuming, will provide
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many benefits to your FreeBSD system. Unlike the GENERIC
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kernel, which must support every possible SCSI and
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network card, along with tons of other rarely used
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hardware support, a custom kernel only contains support
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for <em>your</em> PC's hardware. This has a number of
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benefits:
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<itemize>
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<item>It will take less time to boot because it does not
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have to spend time probing for hardware which you
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do not have.
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<item>A custom kernel often uses less memory, which is
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important because the kernel is the one process which
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must always be present in memory, and so all of that
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unused code ties up pages of RAM that your programs
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would otherwise be able to use. Therefore, on a
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system with limited RAM, building a custom kernel is
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of critical importance.
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<item>Finally, there are several kernel options which
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you can tune to fit your needs, and device driver
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support for things like sound cards which you can
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include in your kernel but are <em>not</em> present
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in the GENERIC kernel.
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</itemize></p>
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<sect><heading>Building and Installing a Custom Kernel</heading>
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<p>First, let us take a quick tour of the kernel build
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directory. All directories mentioned will be relative to
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the main <tt>/usr/src/sys</tt> directory, which is also
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accessible through <tt>/sys</tt>. There are a number of
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subdirectories here representing different parts of the
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kernel, but the most important, for our purposes, are
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<tt>i386/conf</tt>, where you will edit your custom
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kernel configuration, and <tt>compile</tt>, which is the
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staging area where your kernel will be built. Notice the
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logical organization of the directory tree, with each
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supported device, filesystem, and option in its own
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subdirectory. Also, anything inside the <tt>i386</tt>
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directory deals with PC hardware only, while everything
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outside the <tt>i386</tt> directory is common to all
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platforms which FreeBSD could potentially be ported to.
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<quote><em/Note:/ If there is <em>not</em> a
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<tt>/usr/src/sys</tt> directory on your system, then the
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kernel source has not been been installed. Follow the
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instructions for installing packages to add this package
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to your system.</quote>
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Next, move to the <tt>i386/conf</tt> directory and copy
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the GENERIC configuration file to the name you want to
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give your kernel. For example:
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<tscreen><verb>
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# cd /usr/src/sys/i386/conf
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# cp GENERIC MYKERNEL
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</verb></tscreen>
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Traditionally, this name is in all capital letters and,
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if you are maintaining multiple FreeBSD machines with
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different hardware, it's a good idea to name it after
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your machine's hostname. We will call it MYKERNEL for
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the purpose of this example.
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<quote><em/Note:/ You must execute these and all of the
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following commands under the root account or you will get
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``permission denied'' errors.</quote>
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Now, edit MYKERNEL with your favorite text editor. If
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you're just starting out, the only editor available will
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probably be <tt>vi</tt>, which is too complex to explain
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here, but is covered well in many books in the <ref
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id="bibliography" name="bibliography">. Feel free to change the comment
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lines at the top to reflect your configuration or the
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changes you've made to differentiate it from GENERIC.
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If you've build a kernel under SunOS or some other BSD
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operating system, much of this file will be very familiar
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to you. If you're coming from some other operating
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system such as DOS, on the other hand, the GENERIC
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configuration file might seem overwhelming to you, so
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follow the descriptions in the <ref
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id="kernelconfig:config" name="Configuration File">
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section slowly and carefully.
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When you're finished, type the following to compile and
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install your kernel:
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<tscreen><verb>
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# /usr/sbin/config MYKERNEL
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# cd ../../compile/MYKERNEL
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# make depend
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# make
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# make install
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</verb></tscreen>
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The new kernel will be copied to the root directory as
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<tt>/kernel</tt> and the old kernel will be moved to
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<tt>/kernel.old</tt>. Now, shutdown the system and
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reboot to use your kernel. In case something goes wrong,
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there are some <ref id="kernelconfig:trouble" name=
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"troubleshooting"> instructions at the end of this
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document. Be sure to read the section which explains how
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to recover in case your new kernel <ref
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id="kernelconfig:noboot" name="does not boot">.
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<quote><em/Note:/ If you've added any new devices (such
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as sound cards) you may have to add some <ref
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id="kernelconfig:nodes" name="device nodes"> to your
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<tt>/dev</tt> directory before you can use them.</quote>
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<sect><heading>The Configuration File<label id="kernelconfig:config"></heading>
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<p>The general format of a configuration file is quite
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simple. Each line contains a keyword and one or more
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arguments. For simplicity, most lines only contain one
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argument. Anything following a <tt>#</tt> is considered
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a comment and ignored. The following sections describe
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each keyword, generally in the order they are listed in
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GENERIC, although some related keywords have been grouped
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together in a single section (such as Networking) even
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though they are actually scattered throughout the GENERIC
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file. An exhaustive list of options is present in the
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LINT configuration file, located in the same directory as
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GENERIC.
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<sect1><heading>Mandatory Keywords</heading>
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<p>These keywords are required in every kernel you build.
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<descrip>
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<tag>machine ``i386''</tag>
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<p>The first keyword is <tt>machine</tt>, which,
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since FreeBSD only runs on Intel 386 and compatible
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chips, is i386.
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<quote><em>Note:</em> that any keyword which
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contains numbers used as text must be enclosed in
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quotation marks, otherwise <tt>config</tt> gets
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confused and thinks you mean the actual number
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386.</quote>
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<tag>cpu ``<em>cpu_type</em>''</tag>
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<p>The next keyword is <tt>cpu</tt>, which includes
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support for each CPU supported by FreeBSD. The
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possible values of <tt><em>cpu_type</em></tt>
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include:
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<itemize>
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<item>I386_CPU
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<item>I486_CPU
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<item>I586_CPU
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</itemize>
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and multiple instances of the <tt>cpu</tt> line may
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be present with different values of
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<tt><em>cpu_type</em></tt> as are present in the
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GENERIC kernel. For a custom kernel, it is best to
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specify only the cpu you have. If, for example,
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you have an Intel Pentium, use <tt>I586_CPU</tt>
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for <tt><em>cpu_type</em></tt>.
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<tag>ident <em>machine_name</em></tag>
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<p>Next, we have <tt>ident</tt>, which is the
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identification of the kernel. You should change
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this from GENERIC to whatever you named your
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kernel, in this example, MYKERNEL. The value you
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put in <tt>ident</tt> will print when you boot up
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the kernel, so it's useful to give a kernel a
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different name if you want to keep it separate from
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your usual kernel (if you want to build an
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experimental kernel, for example). Note that, as
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with <tt>machine</tt> and <tt> cpu</tt>, enclose
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your kernel's name in quotation marks if it
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contains any numbers.
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Since this name is passed to the C compiler as a
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<tt>-D</tt> switch, don't use names like <tt>
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DEBUG</tt>, or something that could be confused
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with another machine or CPU name, like <tt>vax</tt>.
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<tag>maxusers <em>number</em></tag>
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<p>This file sets the size of a number of important
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system tables. This number is supposed to be
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roughly equal to the number of simultaneous users
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you expect to have on your machine. However, under
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normal circumstances, you will want to set
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<tt>maxusers</tt> to at least four, especially if
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you're using X Windows or compiling software. The
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reason is that the most important table set by
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<tt>maxusers</tt> is the maximum number of
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processes, which is set to <bf><tt>20 + 16 *
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maxusers</tt></bf>, so if you set <tt>maxusers</tt>
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to one, then you can only have 36 simultaneous
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processes, including the 18 or so that the system
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starts up at boot time, and the 15 or so you will
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probably create when you start X Windows. Even a
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simple task like reading a <tt>man</tt> page will
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start up nine processes to filter, decompress, and
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view it. Setting <tt>maxusers</tt> to 4 will allow
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you to have up to 84 simultaneous processes, which
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should be enough for anyone. If, however, you see
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the dreaded ``proc table full'' error when trying
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to start another program, or are running a server
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with a large number of simultaneous users (like
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Walnut Creek CDROM's FTP site), you can always
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increase this number and rebuild.
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<quote><em/Note:/ <tt>maxuser</tt> does
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<em>not</em> limit the number of users which can
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log into your machine. It simply sets various
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table sizes to reasonable values considering the
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maximum number of users you will likely have on
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your system and how many processes each of them
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will be running. One keyword which
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<em>does</em> limit the number of simultaneous
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<em>remote logins</em> is <ref
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id="kernelconfig:ptys" name="pseudo-device pty
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16">.</quote>
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<tag>config <em>kernel_name</em> root on <em>root_device</em></tag>
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<p>This line specifies the location and name of the
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kernel. Traditionally the kernel is called
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<tt>vmunix</tt> but in FreeBSD, it is aptly named
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<tt>kernel</tt>. You should always use
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<tt>kernel</tt> for <em>kernel_name</em> because
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changing it will render numerous system utilities
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inoperative. The second part of the line specifies
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the disk and partition where the root filesystem
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and kernel can be found. Typically this will be
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<tt>wd0</tt> for systems with non-SCSI drives, or
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<tt>sd0</tt> for systems with SCSI drives.
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</descrip>
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<sect1><heading>General Options</heading>
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<p>These lines provide kernel support for various
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filesystems and other options.
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<descrip>
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<label id="kernelconfig:mathemu">
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<tag>options MATH_EMULATE</tag>
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<p>This line allows the kernel to simulate a math
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coprocessor if your computer does not have one (386
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or 486SX). If you have a Pentium, a 486DX, or a
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386 or 486SX with a separate 387 or 487 chip, you
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can comment this line out.
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<quote><em>Note:</em> The normal math coprocessor
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emulation routines that come with FreeBSD are
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<em>not</em> very accurate. If you do not have a
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math coprocessor, and you need the best accuracy,
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I recommend that you change this option to
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<tt>GPL_MATH_EMULATE</tt> to use the superior GNU
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math support, which is not included by default
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for licensing reasons.</quote>
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<tag>options ``COMPAT_43''</tag>
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<p>Compatibility with BSD 4.3. Leave this in; some
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programs will act strangely if you comment this
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out.
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<tag>options BOUNCE_BUFFERS</tag>
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<p>ISA devices and EISA devices operating in an ISA
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compatibilty mode can only perform DMA (Direct
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Memory Access) to memory below 16 megabytes. This
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option enables such devices to work in systems with
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more than 16 megabytes of memory.
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<tag>options UCONSOLE</tag>
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<p>Allow users to grab the console, useful for X
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Windows. For example, you can create a console
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xterm by typing <tt>xterm -C</tt>, which will
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display any `write', `talk', and other messages you
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receive, as well as any console messages sent by the
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kernel.
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<tag>options SYSVSHM</tag>
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<p>This option
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provides for System V shared memory. The most
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common use of this is the XSHM extension in X
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Windows, which many graphics-intensive programs
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(such as the movie player XAnim, and Linux DOOM)
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will automatically take advantage of for extra
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speed. If you use X Windows, you'll definitely
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want to include this.
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<tag>options SYSVSEM</tag>
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<p>Support for System V
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semaphores. Less commonly used but only adds a few
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hundred bytes to the kernel.
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<tag>options SYSVMSG</tag>
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<p>Support for System V
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messages. Again, only adds a few hundred bytes to
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the kernel.
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<quote><em/Note:/ The <tt>ipcs(1)</tt> command will
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tell will list any processes using using each of
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these System V facilities.</quote>
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</descrip>
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<sect1><heading>Filesystem Options</heading>
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<p>These options add support for various filesystems.
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You must include at least one of these to support the
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device you boot from; typically this will be
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<tt>FFS</tt> if you boot from a hard drive, or
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<tt>NFS</tt> if you are booting a diskless workstation
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from Ethernet. You can include other commonly-used
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filesystems in the kernel, but feel free to comment out
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support for filesystems you use less often (perhaps the
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MS-DOS filesystem?), since they will be dynamically
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loaded from the Loadable Kernel Module directory
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<tt>/lkm</tt> the first time you mount a partition of
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that type.
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<descrip>
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<tag>options FFS</tag>
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<p>The basic hard drive
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filesystem; leave it in if you boot from the hard
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disk.
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<tag>options NFS</tag>
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<p>Network Filesystem. Unless
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you plan to mount partitions from a Unix file
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server over Ethernet, you can comment this out.
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<tag>options MSDOSFS</tag>
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<p>MS-DOS Filesystem. Unless
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you plan to mount a DOS formatted hard drive
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partition at boot time, you can safely comment this
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out. It will be automatically loaded the first
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time you mount a DOS partition, as described above.
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Also, the excellent <tt>mtools</tt> software (in
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the ports collection) allows you to access DOS
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floppies without having to mount and unmount them
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(and does not require MSDOSFS at all).
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<tag>options ``CD9660''</tag>
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<p>ISO 9660 filesystem for
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CD-ROMs. Comment it out if you do not have a
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CD-ROM drive or only mount data CD's occasionally
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(since it will be dynamically loaded the first time
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you mount a data CD). Audio CD's do not need this
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filesystem.
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<tag>options PROCFS</tag>
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<p>Process filesystem. This
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is a pretend filesystem mounted on /proc which
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allows programs like <tt>ps(1)</tt> to give you
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more information on what processes are running.
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<tag>options MFS</tag>
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<p>Memory-mapped file system.
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This is basically a RAM disk for fast storage of
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temporary files, useful if you have a lot of swap
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space that you want to take advantage of. A
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perfect place to mount an MFS partition is on the
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<tt>/tmp</tt> directory, since many programs store
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temporary data here. To mount an MFS RAM disk on
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<tt>/tmp</tt>, add the following line to
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<tt>/etc/fstab</tt> and then reboot or type
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<tt>mount /tmp</tt>:
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<tscreen><verb>
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/dev/wd1s2b /tmp mfs rw 0 0
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</verb></tscreen>
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<quote><em/Note:/ Replace the <tt>/dev/wd1s2b</tt>
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with the name of your swap partition, which will
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be listed in your <tt>/etc/fstab</tt> as follows:
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<tscreen><verb>
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/dev/wd1s2b none swap sw 0 0
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</verb></tscreen>
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</quote>
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<quote><em/Note:/ <!-- MFS is currently a bit
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limited (for example, I noticed that two programs
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ca not access the <tt>/tmp</tt> device
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simultaneously). As such, you may want to avoid
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it for now. --> Also, the <tt>MFS</tt> filesystem
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can <em>not</em> be dynamically loaded, so you
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<em>must</em> compile it into your kernel if you
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want to experiment with it.</quote>
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<tag>options QUOTA</tag>
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<p>Enable disk quotas. If you
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have a public access system, and do not want users
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to be able to overflow the <tt>/home</tt>
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partition, you can establish disk quotas for each
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user. This code is a little buggy, so do not
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enable it unless you have to. View the manual page
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for <tt>quota(1)</tt> to learn more about disk
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quotas.
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</descrip>
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<sect1><heading>Basic Controllers and Devices</heading>
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<p>These sections describe the basic disk, tape, and
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CD-ROM controllers supported by FreeBSD. There are
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separate sections for <ref id="kernelconfig:scsi"
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name="SCSI"> controllers and <ref
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id="kernelconfig:network" name="network"> cards.
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<descrip>
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<tag>controller isa0</tag>
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<p>All PC's supported by
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FreeBSD have one of these. If you have an IBM PS/2
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(Micro Channel Architecture), then you cannot run
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FreeBSD at this time.
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<tag>controller pci0</tag>
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<p>Include this if you have a
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PCI motherboard. This enables auto-detection of
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PCI cards and gatewaying from the PCI to the ISA
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bus.
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<tag>controller fdc0</tag>
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<p>Floppy drive controller:
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<tt>fd0</tt> is the ``A:'' floppy drive, and
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<tt>fd1</tt> is the ``B:'' drive. <tt>ft0</tt> is
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a QIC-80 tape drive attached to the floppy
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controller. Comment out any lines corresponding to
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devices you do not have.
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<quote><em/Note:/ QIC-80 tape support requires a
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separate filter program called <tt>ft(8)</tt>, see
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the manual page for details.</quote>
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<tag>controller wdc0</tag>
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<p>This is the primary IDE
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controller. <tt>wd0</tt> and <tt>wd1</tt> are the
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master and slave hard drive, respectively.
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<tt>wdc1</tt> is a secondary IDE controller where
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you might have a third or fourth hard drive, or an
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IDE CD-ROM. Comment out the lines which do not
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apply (if you have a SCSI hard drive, you'll
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probably want to comment out all six lines, for
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example).
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<tag>controller wcd0<label id="kernelconfig:atapi"></tag>
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<p>This device
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provides IDE CD-ROM support. Be sure to leave
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<tt>wdc1</tt> uncommented if your CD-ROM is on
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its own controller card. To use this, you must
|
|
also include the line <tt>options ATAPI</tt>.
|
|
|
|
<tag>device npx0 at isa? port ``IO_NPX'' irq 13 vector npxintr</tag>
|
|
|
|
<p><tt>npx0</tt> is the interface to the math coprocessor.
|
|
If you have a math coprocessor, either an external
|
|
80387 or 80487, or a cpu one built in such as an 80486DX or
|
|
Pentium, then you do <em>not</em> need the <ref
|
|
id="kernelconfig:mathemu" name="MATH_EMULATE"> option above.
|
|
|
|
<tag>device wt0 at isa? port 0x300 bio irq 5 drq 1 vector wtintr</tag>
|
|
|
|
<p>Wangtek and Archive
|
|
QIC-02/QIC-36 tape drive support
|
|
|
|
<tag>Proprietary CD-ROM support</tag>
|
|
|
|
<p>The following
|
|
drivers are for the so-called <em>proprietary</em>
|
|
CD-ROM drives. These drives have their own
|
|
controller card or might plug into a sound card
|
|
such as the Soundblaster 16. They are <em>not</em>
|
|
IDE or SCSI. Most older single-speed and
|
|
double-speed CD-ROMs use these interfaces, while
|
|
newer quad-speeds are likely to be <ref
|
|
id="kernelconfig:atapi" name="IDE"> or <ref
|
|
id="kernelconfig:scsi" name="SCSI">.
|
|
|
|
<descrip>
|
|
|
|
<tag>device mcd0 at isa? port 0x300 bio irq 10 vector mcdintr</tag>
|
|
|
|
<p>Mitsumi CD-ROM (LU002,
|
|
LU005, FX001D).
|
|
|
|
<tag>device scd0 at isa? port 0x230 bio</tag>
|
|
|
|
<p>Sony CD-ROM (CDU31, CDU33A).
|
|
|
|
<tag>controller matcd0 at isa? port ? bio</tag>
|
|
|
|
<p>Matsushita/Panasonic CD-ROM (sold by Creative
|
|
Labs for Soundblaster).
|
|
|
|
</descrip>
|
|
|
|
</descrip>
|
|
|
|
<sect1><heading>SCSI Device Support<label id="kernelconfig:scsi"></heading>
|
|
|
|
<p>This section describes the various SCSI controllers
|
|
and devices supported by FreeBSD.
|
|
|
|
<descrip>
|
|
|
|
<tag>SCSI Controllers</tag>
|
|
|
|
<p>The next ten or so lines include support for
|
|
different kinds of SCSI controllers. Comment out
|
|
all except for the one(s) you have:
|
|
|
|
<descrip>
|
|
|
|
<tag>controller bt0 at isa? port ``IO_BT0'' bio irq ? vector btintr</tag>
|
|
|
|
<p>Most Buslogic controllers
|
|
|
|
<tag>controller uha0 at isa? port ``IO_UHA0'' bio irq ? drq 5 vector uhaintr</tag>
|
|
|
|
<p>UltraStor 14F and 34F
|
|
|
|
<tag>controller ahc0</tag>
|
|
|
|
<p>Adaptec 274x/284x/294x
|
|
|
|
<tag>controller ahb0 at isa? bio irq ? vector ahbintr</tag>
|
|
|
|
<p>Adaptec 174x
|
|
|
|
<tag>controller aha0 at isa? port ``IO_AHA0'' bio irq ? drq 5 vector ahaintr</tag>
|
|
|
|
<p>Adaptec 154x
|
|
|
|
<tag>controller aic0 at isa? port 0x340 bio irq 11 vector aicintr
|
|
</tag>
|
|
|
|
<p>Adaptec 152x and sound cards using Adaptec AIC-6360 (slow!)
|
|
|
|
<tag>controller nca0 at isa? port 0x1f88 bio irq 10 vector ncaintr
|
|
</tag>
|
|
|
|
<p>ProAudioSpectrum cards using NCR 5380 or Trantor T130
|
|
|
|
<tag>controller sea0 at isa? bio irq 5 iomem 0xc8000 iosiz 0x2000 vector seaintr</tag>
|
|
|
|
<p>Seagate ST01/02 8 bit controller (slow!)
|
|
|
|
<tag>controller wds0 at isa? port 0x350 bio irq 15 drq 6 vector wdsintr</tag>
|
|
|
|
<p>Western Digital WD7000 controller
|
|
|
|
<tag>controller ncr0</tag>
|
|
|
|
<p>NCR 53C810 and 53C825 PCI SCSI controller
|
|
|
|
</descrip>
|
|
|
|
<tag>options ``SCSI_DELAY=15''</tag>
|
|
|
|
<p>This causes the
|
|
kernel to pause 15 seconds before probing each SCSI
|
|
device in your system. If you only have IDE hard
|
|
drives, you can ignore this, otherwise you'll
|
|
probably want to lower this number, perhaps to 5
|
|
seconds, to speed up booting. Of course if you do
|
|
this, and FreeBSD has trouble recognizing your SCSI
|
|
devices, you'll have to raise it back up.
|
|
|
|
<tag>controller scbus0</tag>
|
|
|
|
<p>If you have any SCSI
|
|
controllers, this line provides generic SCSI
|
|
support. If you do not have SCSI, you can comment
|
|
this, and the following three lines, out.
|
|
|
|
<tag>device sd0</tag>
|
|
|
|
<p>Support for SCSI hard
|
|
drives.
|
|
|
|
<tag>device st0</tag>
|
|
|
|
<p>Support for SCSI tape
|
|
drives.
|
|
|
|
<tag>device cd0</tag>
|
|
|
|
<p>Support for SCSI CD-ROM
|
|
drives.
|
|
|
|
<p>Note that the number <bf>0</bf> in the above entries
|
|
is slightly misleading: all these devices are
|
|
automatically configured as they are found, regardless
|
|
of how many of them are hooked up to the SCSI bus(es),
|
|
and which target IDs they have.
|
|
|
|
If you want to ``wire down'' specific target IDs to
|
|
particular devices, refer to the appropriate section
|
|
of the LINT kernel config file.
|
|
|
|
</descrip>
|
|
|
|
<sect1><heading>Console, Bus Mouse, and X Server Support</heading>
|
|
|
|
<p>You must choose one of these two console types, and, if you plan
|
|
to use X Windows, enable the XSERVER option and optionally, a bus
|
|
mouse or PS/2 mouse device.
|
|
|
|
<descrip>
|
|
|
|
<tag>device sc0 at isa? port ``IO_KBD' tty irq 1 vector scintr</tag>
|
|
|
|
<p><tt>sc0</tt> is the default
|
|
console driver, which resembles an SCO console.
|
|
Since most full-screen programs access the console
|
|
through a terminal database library like
|
|
<em>termcap</em>, it should not matter much whether
|
|
you use this or <tt>vt0</tt>, the VT220 compatible
|
|
console driver. When you log in, set your TERM
|
|
variable to ``scoansi'' if full-screen programs
|
|
have trouble running under this console.
|
|
|
|
<tag>device vt0 at isa? port ``IO_KBD'' tty irq 1 vector pcrint</tag>
|
|
|
|
<p>This is a VT220-compatible
|
|
console driver, backwards compatible to VT100/102.
|
|
It works well on some laptops which have hardware
|
|
incompatibilities with <tt>sc0</tt>. Also, set
|
|
your TERM variable to ``vt100'' or ``vt220'' when
|
|
you log in. This driver might also prove useful
|
|
when connecting to a large number of different
|
|
machines over the network, where the <em>termcap</em>
|
|
or <em>terminfo</em> entries for the <tt>sc0</tt>
|
|
device are often not available -- ``vt100'' should be
|
|
available on virtually any platform.
|
|
|
|
<descrip>
|
|
|
|
<tag>options ``PCVT_FREEBSD=210''</tag>
|
|
|
|
<p>Required
|
|
with the <tt>vt0</tt> console driver.
|
|
|
|
<tag>options XSERVER</tag>
|
|
|
|
<p>This includes code
|
|
required to run the <tt>XFree86</tt> X Window
|
|
Server.
|
|
|
|
</descrip>
|
|
|
|
<tag>device mse0 at isa? port 0x23c tty irq 5 vector ms</tag>
|
|
|
|
<p>Use this device if you have a Logitech or
|
|
ATI InPort bus mouse card.
|
|
|
|
<quote><em/Note:/ If you have a serial mouse,
|
|
ignore these two lines, and instead, make sure
|
|
the appropriate <ref id="kernelconfig:serial"
|
|
name="serial"> port is enabled (probably
|
|
COM1).</quote>
|
|
|
|
<tag>device psm0 at isa? port ``IO_KBD'' conflicts tty irq 12 vector psmintr</tag>
|
|
|
|
<p>Use this device if your
|
|
mouse plugs into the PS/2 mouse port.
|
|
|
|
</descrip>
|
|
|
|
<sect1><heading>Serial and Parallel Ports</heading>
|
|
|
|
<p>Nearly all systems have these. If you are attaching a
|
|
printer to one of these ports, the <ref id="printing"
|
|
name="Printing"> section of the handbook is very
|
|
useful. If you are using modem, <ref id="dialup"
|
|
name="Dialup access"> provides extensive detail on
|
|
serial port configuration for use with such devices.
|
|
|
|
<descrip>
|
|
|
|
<tag>device sio0 at isa? port ``IO_COM1'' tty irq 4 vector siointr<label id="kernelconfig:serial"></tag>
|
|
|
|
<p><tt>sio0</tt>
|
|
through <tt>sio3</tt> are the four serial ports
|
|
referred to as COM1 through COM4 in the MS-DOS
|
|
world. Note that if you have an internal modem on
|
|
COM4 and a serial port at COM2 you will have to
|
|
change the IRQ of the modem to 2 (for obscure
|
|
technical reasons IRQ 2 = IRQ 9) in order to access
|
|
it from FreeBSD. If you have a multiport serial
|
|
card, check the manual page for <tt>sio(4)</tt> for
|
|
more information on the proper values for these
|
|
lines. Some video cards (notably
|
|
those based on S3 chips) use IO addresses of the
|
|
form <tt>0x*2e8</tt>, and since many cheap serial
|
|
cards do not fully decode the 16-bit IO address
|
|
space, they clash with these cards, making the
|
|
COM4 port practically unavailable.
|
|
|
|
Each serial port is required to have a unique
|
|
IRQ (unless you are using one of the multiport cards
|
|
where shared interrupts are supported), so the default
|
|
IRQs for COM3 and COM4 cannot be used.
|
|
|
|
<tag>device lpt0 at isa? port? tty irq 7 vector lptintr</tag>
|
|
|
|
<p><tt>lpt0</tt> through <tt>lpt2</tt>
|
|
are the three printer ports you could conceivably
|
|
have. Most people just have one, though, so feel
|
|
free to comment out the other two lines if you do
|
|
not have them.
|
|
|
|
</descrip>
|
|
|
|
<sect1><heading>Networking<label id="kernelconfig:network"></heading>
|
|
|
|
<p>FreeBSD, as with Unix in general, places a
|
|
<em>big</em> emphasis on networking. Therefore, even
|
|
if you do not have an Ethernet card, pay attention to
|
|
the mandatory options and the dial-up networking
|
|
support.
|
|
|
|
<descrip>
|
|
|
|
<tag>options INET</tag>
|
|
Networking support. Leave it in even if you do not plan
|
|
to be connected to a network. Most programs require at least
|
|
loopback networking (i.e. making network connections within your
|
|
PC) so this is essentially mandatory.
|
|
|
|
<tag>Ethernet cards</tag>
|
|
|
|
<p>The next lines enable support for various Ethernet
|
|
cards. If you do not have a network card, you can
|
|
comment out all of these lines. Otherwise, you'll
|
|
want to leave in support for your particular
|
|
Ethernet card(s):
|
|
|
|
<descrip>
|
|
|
|
<tag>device de0</tag>
|
|
|
|
<p>Digital Equipment DC21040 PCI Ethernet adapter
|
|
|
|
<tag>device cx0 at isa? port 0x240 net irq 15 drq 7 vector cxintr</tag>
|
|
|
|
<p>Cronyx/Sigma multiport
|
|
sync/async (with Cisco or PPP framing)
|
|
|
|
<tag>device ed0 at isa? port 0x280 net irq 5 iomem 0xd8000 vector edintr</tag>
|
|
|
|
<p>Western Digital and SMC 80xx; Novell NE1000
|
|
and NE2000; 3Com 3C503
|
|
|
|
<tag>device el0 at isa? port 0x300 net irq 9 vector elintr</tag>
|
|
|
|
<p>3Com 3C501 (slow!)
|
|
|
|
<tag>device eg0 at isa? port 0x310 net irq 5 vector egintr</tag>
|
|
|
|
<p>3Com 3C505
|
|
|
|
<tag>device ep0 at isa? port 0x300 net irq 10 vector epintr</tag>
|
|
|
|
<p>3Com 3C509 (buggy)
|
|
|
|
<tag>device fe0 at isa? port 0x240 net irq ? vector feintr</tag>
|
|
|
|
<p>Fujitsu MB86960A/MB86965A Ethernet
|
|
|
|
<tag>device fea0 at isa? net irq ? vector feaintr</tag>
|
|
|
|
<p>DEC DEFEA EISA FDDI adapter
|
|
|
|
<tag>device ie0 at isa? port 0x360 net irq 7 iomem 0xd0000 vector ieintr</tag>
|
|
|
|
<p>AT&T StarLAN 10 and EN100; 3Com 3C507;
|
|
unknown NI5210
|
|
|
|
<tag>device ix0 at isa? port 0x300 net irq 10 iomem 0xd0000 iosiz 32768 vector ixintr</tag>
|
|
|
|
<p>Intel EtherExpress 16
|
|
|
|
<tag>device le0 at isa? port 0x300 net irq 5 iomem 0xd0000 vector le_intr</tag>
|
|
|
|
<p>Digital Equipment EtherWorks 2 and EtherWorks
|
|
3 (DEPCA, DE100, DE101, DE200, DE201, DE202,
|
|
DE203, DE204, DE205, DE422)
|
|
|
|
<tag>device lnc0 at isa? port 0x300 net irq 10 drq 0 vector lncintr</tag>
|
|
|
|
<p>Lance/PCnet cards (Isolan, Novell NE2100,
|
|
NE32-VL)
|
|
|
|
<tag>device ze0 at isa? port 0x300 net irq 5 iomem 0xd8000 vector zeintr</tag>
|
|
|
|
<p>IBM/National Semiconductor PCMCIA ethernet
|
|
controller.
|
|
|
|
<tag>device zp0 at isa? port 0x300 net irq 10 iomem 0xd8000 vector zpintr</tag>
|
|
|
|
<p>3Com PCMCIA Etherlink III
|
|
|
|
</descrip>
|
|
|
|
<quote><em/Note:/ With certain cards (notably the
|
|
NE2000) you'll have to change the port and/or IRQ
|
|
since there is no ``standard'' location for these
|
|
cards.</quote>
|
|
|
|
<tag>pseudo-device loop</tag>
|
|
|
|
<p><tt>loop</tt> is the
|
|
generic loopback device for TCP/IP. If you telnet
|
|
or FTP to <em>localhost</em>
|
|
(a.k.a. <tt>127.0.0.1</tt>) it will come back at
|
|
you through this pseudo-device. Mandatory.
|
|
|
|
<tag>pseudo-device ether</tag>
|
|
|
|
<p><tt>ether</tt> is only
|
|
needed if you have an Ethernet card and includes
|
|
generic Ethernet protocol code.
|
|
|
|
<tag>pseudo-device sl <em>number</em></tag>
|
|
|
|
<p><tt>sl</tt> is for SLIP (Serial Line Internet
|
|
Protocol) support. This has been almost entirely
|
|
supplanted by PPP, which is easier to set up,
|
|
better suited for modem-to-modem connections, as
|
|
well as more powerful. The <em>number</em> after
|
|
<tt>sl</tt> specifies how many simultaneous SLIP
|
|
sessions to support. This handbook has more
|
|
information on setting up a SLIP <ref id="slipc"
|
|
name="client"> or <ref id="slips" name="server">.
|
|
|
|
<tag>pseudo-device ppp <em>number</em></tag>
|
|
|
|
<p><tt>ppp</tt> is for kernel-mode PPP (Point-to-Point
|
|
Protocol) support for dial-up Internet connections.
|
|
There is also version of PPP implemented as a user
|
|
application that uses the <tt>tun</tt> and offers
|
|
more flexibility and features such as demand
|
|
dialing. If you still want to use this PPP driver,
|
|
read the <ref id="ppp" name="kernel-mode PPP">
|
|
section of the handbook. As with the <tt>sl</tt>
|
|
device, <em>number</em> specifies how many
|
|
simultaneous PPP connections to support.
|
|
|
|
<tag>pseudo-device tun <em>number</em></tag>
|
|
|
|
<p><tt>tun</tt> is used by the user-mode PPP software.
|
|
This program is easy to set up and very fast. It
|
|
also has special features such as automatic
|
|
dial-on-demand. The number after <tt>tun</tt>
|
|
specifies the number of simultaneous PPP sessions
|
|
to support. See the <ref id="userppp"
|
|
name="user-mode PPP"> section of the handbook for
|
|
more information.
|
|
|
|
<tag>pseudo-device bpfilter <em>number</em></tag>
|
|
|
|
<p>Berkeley packet filter. This pseudo-device allows
|
|
network interfaces to be placed in promiscuous
|
|
mode, capturing every packet on a broadcast network
|
|
(e.g. an ethernet). These packets can be captured
|
|
to disk and/or examined with the
|
|
<tt>tcpdump(1)</tt> program. Note that
|
|
implementation of this capability can seriously
|
|
compromise your overall network security.
|
|
The <em>number</em> after bpfilter is the number of
|
|
interfaces that can be examined
|
|
simultaneously. Optional, not recommended except
|
|
for those who are fully aware of the potential
|
|
pitfalls. Not all network cards support this
|
|
capability.
|
|
|
|
</descrip>
|
|
|
|
<sect1><heading>Sound cards</heading>
|
|
|
|
<p>This is the first section containing lines that are
|
|
not in the GENERIC kernel. To include sound card
|
|
support, you'll have to copy the appropriate lines from
|
|
the LINT kernel (which contains support for
|
|
<em>every</em> device) as follows:
|
|
|
|
<descrip>
|
|
|
|
<tag>controller snd0</tag>
|
|
|
|
<p>Generic sound driver code.
|
|
Required for all of the following sound cards
|
|
except <tt>pca</tt>.
|
|
|
|
<tag>device pas0 at isa? port 0x388 irq 10 drq 6 vector pasintr</tag>
|
|
|
|
<p>ProAudioSpectrum digital audio and MIDI.
|
|
|
|
<tag>device sb0 at isa? port 0x220 irq 7 conflicts drq 1 vector sbintr</tag>
|
|
|
|
<p>SoundBlaster digital audio.
|
|
|
|
<quote><em/Note:/ If your Soundblaster is on a
|
|
different IRQ (such as 5), change <tt>irq 7</tt>
|
|
to, for example, <tt>irq 5</tt> and remove the
|
|
<tt>conflicts</tt> keyword. Also, you must add
|
|
the line: <tt>options ``SBC_IRQ=5''</tt></quote>
|
|
|
|
<tag>device sbxvi0 at isa? drq 5</tag>
|
|
|
|
<p>SoundBlaster 16 digital 16-bit audio.
|
|
|
|
<quote><em/Note:/ If your SB16 is on a different
|
|
16-bit DMA channel (such as 6 or 7), change the
|
|
<tt>drq 5</tt> keyword appropriately, and then
|
|
add the line: <tt>options
|
|
"SB16_DMA=6"</tt></quote>
|
|
|
|
<tag>device sbmidi0 at isa? port 0x330</tag>
|
|
|
|
<p>SoundBlaster 16 MIDI interface. If you have a
|
|
SoundBlaster 16, you must include this line, or the
|
|
kernel will not compile.
|
|
|
|
<tag>device gus0 at isa? port 0x220 irq 10 drq 1 vector gusintr</tag>
|
|
|
|
<p>Gravis Ultrasound.
|
|
|
|
<tag>device mss0 at isa? port 0x530 irq 10 drq 1 vector adintr</tag>
|
|
|
|
<p>Microsoft Sound System.
|
|
|
|
<tag>device opl0 at isa? port 0x388 conflicts</tag>
|
|
|
|
<p>AdLib FM-synthesis audio. Include this line for
|
|
AdLib, SoundBlaster, and ProAudioSpectrum users, if
|
|
you want to play MIDI songs with a program such as
|
|
<tt>playmidi</tt> (in the ports collection).
|
|
|
|
<tag>device mpu0 at isa? port 0x330 irq 6 drq 0</tag>
|
|
|
|
<p>Roland MPU-401 stand-alone card.
|
|
|
|
<tag>device uart0 at isa? port 0x330 irq 5 vector ``m6850intr''</tag>
|
|
|
|
<p>Stand-alone 6850 UART for MIDI.
|
|
|
|
<tag>device pca0 at isa? port ``IO_TIMER1'' tty<label id="kernelconfig:pcaudio"></tag>
|
|
|
|
<p>Digital audio through PC speaker. This is going to
|
|
be very poor sound quality and quite CPU-intensive,
|
|
so you have been warned (but it does not require a
|
|
sound card).
|
|
|
|
</descrip>
|
|
|
|
<quote><em/Note:/ There is some additional
|
|
documentation in
|
|
<tt>/usr/src/sys/i386/isa/sound/sound.doc</tt>.
|
|
Also, if you add any of these devices, be sure to
|
|
create the sound <ref id="kernelconfig:nodes"
|
|
name="device nodes">.</quote>
|
|
|
|
<sect1><heading>Pseudo-devices</heading>
|
|
|
|
<p>Pseudo-device drivers are parts of the kernel that act
|
|
like device drivers but do not correspond to any actual
|
|
hardware in the machine. The <ref
|
|
id="kernelconfig:network" name="network-related">
|
|
pseudo-devices are in that section, while the remainder
|
|
are here.
|
|
|
|
<descrip>
|
|
|
|
<tag>pseudo-device gzip</tag>
|
|
|
|
<p><tt>gzip</tt> allows you to run FreeBSD programs
|
|
that have been compressed with <tt>gzip</tt>. The
|
|
programs in <tt>/stand</tt> are compressed so it
|
|
is a good idea to have this option in your kernel.</p>
|
|
|
|
<tag>pseudo-device log</tag>
|
|
|
|
<p><tt>log</tt> is used for logging of kernel error
|
|
messages. Mandatory.
|
|
|
|
|
|
<tag>pseudo-device pty <em>number</em><label id="kernelconfig:ptys"></tag>
|
|
|
|
<p><tt>pty</tt> is a ``pseudo-terminal'' or simulated
|
|
login port. It's used by incoming <bf>telnet</bf>
|
|
and <bf>rlogin</bf> sessions, xterm, and some other
|
|
applications such as emacs. The <em>number</em>
|
|
indicates the number of <tt>pty</tt>s to create.
|
|
If you need more than GENERIC default of 16
|
|
simultaneous xterm windows and/or remote logins, be
|
|
sure to increase this number accordingly, up to a
|
|
maximum of 64.
|
|
|
|
<tag>pseudo-device snp <em>number</em></tag>
|
|
|
|
<p>Snoop device. This pseudo-device allows one
|
|
terminal session to watch another using the
|
|
<tt>watch(8)</tt> command. Note that
|
|
implementation of this capability has important
|
|
security and privacy implications. The
|
|
<em>number</em> after snp is the total number of
|
|
simultaneous snoop sessions. Optional.
|
|
|
|
<tag>pseudo-device vn</tag>
|
|
|
|
<p>Vnode driver. Allows a file to be treated as a
|
|
device after being set up with the
|
|
<tt>vnconfig(8)</tt> command. This driver can be
|
|
useful for manipulating floppy disk images and
|
|
using a file as a swap device (e.g. an MS Windows
|
|
swap file). Optional.
|
|
|
|
</descrip>
|
|
|
|
<sect1><heading>Joystick, PC Speaker, Miscellaneous</heading>
|
|
|
|
<p>This section describes some miscellaneous hardware
|
|
devices supported by FreeBSD. Note that none of these
|
|
lines are included in the GENERIC kernel, you'll have
|
|
to copy them from this handbook or the LINT kernel
|
|
(which contains support for <em>every</em> device):
|
|
|
|
<descrip>
|
|
|
|
<tag>device joy0 at isa? port ``IO_GAME''</tag>
|
|
|
|
<p>PC joystick device.
|
|
|
|
<tag>pseudo-device speaker</tag>
|
|
|
|
<p>Supports IBM BASIC-style noises through the PC
|
|
speaker. Some fun programs which use this are
|
|
<tt>/usr/sbin/spkrtest</tt>, which is a shell
|
|
script that plays some simple songs, and
|
|
<tt>/usr/games/piano</tt> which lets you play songs
|
|
using the keyboard as a simple piano (this file
|
|
only exists if you've installed the <em>games</em>
|
|
package). Also, the excellent text role-playing
|
|
game NetHack (in the ports collection) can be
|
|
configured to use this device to play songs when
|
|
you play musical instruments in the game.
|
|
|
|
<p>See also the <ref id="kernelconfig:pcaudio"
|
|
name="pca0"> device.
|
|
|
|
</descrip>
|
|
|
|
<sect><heading>Making Device Nodes<label id="kernelconfig:nodes"></heading>
|
|
|
|
<p>Almost every device in the kernel has a corresponding
|
|
``node'' entry in the <tt>/dev</tt> directory. These
|
|
nodes look like regular files, but are actually special
|
|
entries into the kernel which programs use to access the
|
|
device. The shell script <tt>/dev/MAKEDEV</tt>, which is
|
|
executed when you first install the operating system,
|
|
creates nearly all of the device nodes supported.
|
|
However, it does not create <em>all</em> of them, so when
|
|
you add support for a new device, it pays to make sure
|
|
that the appropriate entries are in this directory, and
|
|
if not, add them. Here is a simple example:
|
|
|
|
Suppose you add the IDE CD-ROM support to the kernel.
|
|
The line to add is:
|
|
<tscreen><verb>
|
|
controller wcd0
|
|
</verb></tscreen>
|
|
This means that you should look for some entries that
|
|
start with <tt>wcd0</tt> in the <tt>/dev</tt> directory,
|
|
possibly followed by a letter, such as `c', or preceded
|
|
by the letter 'r', which means a `raw' device. It turns
|
|
out that those files are not there, so I must change to
|
|
the <tt>/dev</tt> directory and type:
|
|
<tscreen><verb>
|
|
# sh MAKEDEV wcd0
|
|
</verb></tscreen>
|
|
When this script finishes, you will find that there are
|
|
now <tt>wcd0c</tt> and <tt>rwcd0c</tt> entries in
|
|
<tt>/dev</tt> so you know that it executed correctly.
|
|
|
|
For sound cards, the command:
|
|
<tscreen><verb>
|
|
# sh MAKEDEV snd0
|
|
</verb></tscreen>
|
|
creates the appropriate entries. Follow this simple
|
|
procedure for any other non-GENERIC devices which do not
|
|
have entries.
|
|
|
|
<quote><em/Note:/ All SCSI controllers use the same set
|
|
of <tt>/dev</tt> entries, so you do not need to create
|
|
these. Also, network cards and SLIP/PPP pseudo-devices
|
|
do not have entries in <tt>/dev</tt> at all, so you do
|
|
not have to worry about these either.</quote>
|
|
|
|
<sect><heading>If Something Goes Wrong<label id="kernelconfig:trouble"></heading>
|
|
|
|
<p>There are four categories of trouble that can occur when
|
|
building a custom kernel. They are:
|
|
|
|
<descrip>
|
|
|
|
<tag>Config command fails</tag>
|
|
|
|
<p>If the <tt>config</tt>
|
|
command fails when you give it your kernel
|
|
description, you've probably made a simple error
|
|
somewhere. Fortunately, <tt>config</tt> will print
|
|
the line number that it had trouble with, so you can
|
|
quickly skip to it with <tt>vi</tt>. For example, if
|
|
you see:
|
|
<tscreen><verb>
|
|
config: line 17: syntax error
|
|
</verb></tscreen>
|
|
you can skip to the problem in <tt>vi</tt> by typing
|
|
``17G'' in command mode. Make sure the keyword is
|
|
typed correctly, by comparing it to the GENERIC
|
|
kernel or another reference.
|
|
|
|
<tag>Make command fails</tag>
|
|
|
|
<p>If the <tt>make</tt>
|
|
command fails, it usually signals an error in your
|
|
kernel description, but not severe enough for
|
|
<tt>config</tt> to catch it. Again, look over your
|
|
configuration, and if you still cannot resolve the
|
|
problem, send mail to <tt><htmlurl
|
|
url="mailto:questions@freebsd.org"
|
|
name="questions@FreeBSD.ORG"></tt> with your kernel
|
|
configuration, and it should be diagnosed very
|
|
quickly.
|
|
|
|
<tag>Kernel will not boot<label id="kernelconfig:noboot"></tag>
|
|
|
|
<p>If your new kernel
|
|
does not boot, or fails to recognize your devices,
|
|
do not panic! Fortunately, BSD has an excellent
|
|
mechanism for recovering from incompatible kernels.
|
|
Simply type the name of the kernel you want to boot
|
|
from (i.e. ``kernel.old'') at the FreeBSD boot
|
|
prompt instead of pressing return. When
|
|
reconfiguring a kernel, it is always a good idea to
|
|
keep a kernel that is known to work on hand.
|
|
|
|
After booting with a good kernel you can check over
|
|
your configuration file and try to build it again.
|
|
One helpful resource is the
|
|
<tt>/var/log/messages</tt> file which records, among
|
|
other things, all of the kernel messages from every
|
|
successful boot. Also, the <tt>dmesg(8)</tt> command
|
|
will print the kernel messages from the current boot.
|
|
|
|
<quote><em/Note:/ If you are having trouble building
|
|
a kernel, make sure to keep a GENERIC, or some
|
|
other kernel that is known to work on hand as a
|
|
different name that will not get erased on the next
|
|
build. You cannot rely on <tt>kernel.old</tt>
|
|
because when installing a new kernel,
|
|
<tt>kernel.old</tt> is overwritten with the last
|
|
installed kernel which may be non-functional.
|
|
Also, as soon as possible, move the working kernel
|
|
to the proper ``kernel'' location or commands such
|
|
as <tt>ps(1)</tt> will not work properly. The
|
|
proper command to ``unlock'' the kernel file that
|
|
<tt>make</tt> installs (in order to move another
|
|
kernel back permanently) is:
|
|
<tscreen><verb>
|
|
# chflags noschg /kernel
|
|
</verb></tscreen>
|
|
And, if you want to ``lock'' your new kernel into place, or any file
|
|
for that matter, so that it cannot be moved or tampered with:
|
|
<tscreen><verb>
|
|
# chflags schg /kernel
|
|
</verb></tscreen>
|
|
</quote>
|
|
|
|
<tag>Kernel works, but <tt>ps</tt> does not work any more!</tag>
|
|
|
|
<p>If you've installed a different version
|
|
of the kernel from the one that the system utilities
|
|
have been built with, for example, an experimental
|
|
``2.2.0'' kernel on a 2.1.0-RELEASE system, many
|
|
system-status commands like <tt>ps(1)</tt> and
|
|
<tt>vmstat(8)</tt> will not work any more. You must
|
|
recompile the <tt>libkvm</tt> library as well as
|
|
these utilities. This is one reason it is not
|
|
normally a good idea to use a different version of
|
|
the kernel from the rest of the operating system.
|
|
|
|
</descrip>
|