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some basic cleanup, stylistic change for config files, and slight fixes 

SVN-Revision: 5455
lede-17.01
Tim Yardley 2006-11-06 23:37:55 +00:00
parent 62dc30f27a
commit 6c8d5185bf
6 changed files with 187 additions and 187 deletions
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166
docs/build.tex
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@ -1,20 +1,20 @@
One of the biggest challenges to getting started with embedded devices is that you
just can't install a copy of Linux and expect to be able to compile a firmware.
Even if you did remember to install a compiler and every development tool offered,
Even if you did remember to install a compiler and every development tool offered,
you still wouldn't have the basic set of tools needed to produce a firmware image.
The embedded device represents an entirely new hardware platform, which is
incompatible with the hardware on your development machine, so in a process called
incompatible with the hardware on your development machine, so in a process called
cross compiling you need to produce a new compiler capable of generating code for
your embedded platform, and then use it to compile a basic Linux distribution to
your embedded platform, and then use it to compile a basic Linux distribution to
run on your device.
The process of creating a cross compiler can be tricky, it's not something that's
regularly attempted and so the there's a certain amount of mystery and black magic
The process of creating a cross compiler can be tricky, it's not something that's
regularly attempted and so the there's a certain amount of mystery and black magic
associated with it. In many cases when you're dealing with embedded devices you'll
be provided with a binary copy of a compiler and basic libraries rather than
instructions for creating your own -- it's a time saving step but at the same time
often means you'll be using a rather dated set. Likewise, it's also common to be
provided with a patched copy of the Linux kernel from the board or chip vendor,
be provided with a binary copy of a compiler and basic libraries rather than
instructions for creating your own -- it's a time saving step but at the same time
often means you'll be using a rather dated set. Likewise, it's also common to be
provided with a patched copy of the Linux kernel from the board or chip vendor,
but this is also dated and it can be difficult to spot exactly what has been
changed to make the kernel run on the embedded platform.
@ -22,17 +22,17 @@ changed to make the kernel run on the embedded platform.
OpenWrt takes a different approach to building a firmware, downloading, patching
and compiling everything from scratch, including the cross compiler. Or to put it
in simpler terms, OpenWrt doesn't contain any executables or even sources, it's an
automated system for downloading the sources, patching them to work with the given
in simpler terms, OpenWrt doesn't contain any executables or even sources, it's an
automated system for downloading the sources, patching them to work with the given
platform and compiling them correctly for the platform. What this means is that
just by changing the template, you can change any step in the process.
As an example, if a new kernel is released, a simple change to one of the Makefiles
As an example, if a new kernel is released, a simple change to one of the Makefiles
will download the latest kernel, patch it to run on the embedded platform and produce
a new firmware image -- there's no work to be done trying to track down an unmodified
copy of the existing kernel to see what changes had been made, the patches are
already provided and the process ends up almost completely transparent. This doesn't
a new firmware image -- there's no work to be done trying to track down an unmodified
copy of the existing kernel to see what changes had been made, the patches are
already provided and the process ends up almost completely transparent. This doesn't
just apply to the kernel, but to anything included with OpenWrt -- It's this one
simple understated concept which is what allows OpenWrt to stay on the bleeding edge
with the latest compilers, latest kernels and latest applications.
@ -58,14 +58,14 @@ which can be used to monitor svn commits and browse the sources.
There are four key directories in the base:
\begin{itemize}
\item tools
\item toolchain
\item package
\item target
\item tools
\item toolchain
\item package
\item target
\end{itemize}
\texttt{tools} and \texttt{toolchain} refer to common tools which will be
used to build the firmware image and the compiler and c library.
used to build the firmware image and the compiler and c library.
The result of this is three new directories, \texttt{tool\_build}, which is a temporary
directory for building the target independent tools, \texttt{toolchain\_build\_\textit{<arch>}}
which is used for building the toolchain for a specific architecture, and
@ -73,13 +73,13 @@ which is used for building the toolchain for a specific architecture, and
You won't need to do anything with the toolchain directory unless you intend to
add a new version of one of the components above.
\texttt{package} is for exactly that -- packages. In an OpenWrt firmware, almost everything
\texttt{package} is for exactly that -- packages. In an OpenWrt firmware, almost everything
is an \texttt{.ipk}, a software package which can be added to the firmware to provide new
features or removed to save space.
\texttt{target} refers to the embedded platform, this contains items which are specific to
a specific embedded platform. Of particular interest here is the "\texttt{target/linux}"
directory which is broken down by platform and contains the kernel config and patches
a specific embedded platform. Of particular interest here is the "\texttt{target/linux}"
directory which is broken down by platform and contains the kernel config and patches
to the kernel for a particular platform. There's also the "\texttt{target/image}" directory
which describes how to package a firmware for a specific platform.
@ -95,20 +95,20 @@ simple enough that an inexperienced end user can easily build his or her own cus
Running the command "\texttt{make menuconfig}" will bring up OpenWrt's configuration menu
screen, through this menu you can select which platform you're targeting, which versions of
the toolchain you want to use to build and what packages you want to install into the
firmware image. Similar to the linux kernel config, almost every option has three choices,
the toolchain you want to use to build and what packages you want to install into the
firmware image. Similar to the linux kernel config, almost every option has three choices,
\texttt{y/m/n} which are represented as follows:
\begin{itemize}
\item{\texttt{<*>} (pressing y)} \\
This will be included in the firmware image
\item{\texttt{<M>} (pressing m)} \\
This will be compiled but not included (for later install)
\item{\texttt{< >} (pressing n)} \\
This will not be compiled
\item{\texttt{<*>} (pressing y)} \\
This will be included in the firmware image
\item{\texttt{<M>} (pressing m)} \\
This will be compiled but not included (for later install)
\item{\texttt{< >} (pressing n)} \\
This will not be compiled
\end{itemize}
After you've finished with the menu configuration, exit and when prompted, save your
After you've finished with the menu configuration, exit and when prompted, save your
configuration changes. To begin compiling the firmware, type "\texttt{make}". By default
OpenWrt will only display a high level overview of the compile process and not each individual
command.
@ -126,10 +126,10 @@ make[4] -C target/utils prepare
\end{Verbatim}
This makes it easier to monitor which step it's actually compiling and reduces the amount
of noise caused by the compile output. To see the full output, run the command
of noise caused by the compile output. To see the full output, run the command
"\texttt{make V=99}".
During the build process, buildroot will download all sources to the "\texttt{dl}"
During the build process, buildroot will download all sources to the "\texttt{dl}"
directory and will start patching and compiling them in the "\texttt{build\_\textit{<arch>}}"
directory. When finished, the resulting firmware will be in the "\texttt{bin}" directory
and packages will be in the "\texttt{bin/packages}" directory.
@ -143,8 +143,8 @@ incredibly easy to port software to OpenWrt. If you look at a typical package di
in OpenWrt you'll find two things:
\begin{itemize}
\item \texttt{package/\textit{<name>}/Makefile}
\item \texttt{package/\textit{<name>}/patches}
\item \texttt{package/\textit{<name>}/Makefile}
\item \texttt{package/\textit{<name>}/patches}
\end{itemize}
The patches directory is optional and typically contains bug fixes or optimizations to
@ -193,9 +193,9 @@ define Build/Configure
endef
define Package/bridge/install
install -m0755 -d $(1)/usr/sbin
install -m0755 $(PKG_BUILD_DIR)/brctl/brctl \
$(1)/usr/sbin/
install -m0755 -d $(1)/usr/sbin
install -m0755 $(PKG_BUILD_DIR)/brctl/brctl \
$(1)/usr/sbin/
endef
$(eval $(call BuildPackage,bridge))
@ -206,32 +206,32 @@ As you can see, there's not much work to be done; everything is hidden in other
and abstracted to the point where you only need to specify a few variables.
\begin{itemize}
\item \texttt{PKG\_NAME} \\
The name of the package, as seen via menuconfig and ipkg
\item \texttt{PKG\_VERSION} \\
The upstream version number that we're downloading
\item \texttt{PKG\_RELEASE} \\
The version of this package Makefile
\item \texttt{PKG\_BUILD\_DIR} \\
Where to compile the package
\item \texttt{PKG\_SOURCE} \\
The filename of the original sources
\item \texttt{PKG\_SOURCE\_URL} \\
Where to download the sources from
\item \texttt{PKG\_MD5SUM} \\
A checksum to validate the download
\item \texttt{PKG\_CAT} \\
How to decompress the sources (zcat, bzcat, unzip)
\item \texttt{PKG\_NAME} \\
The name of the package, as seen via menuconfig and ipkg
\item \texttt{PKG\_VERSION} \\
The upstream version number that we're downloading
\item \texttt{PKG\_RELEASE} \\
The version of this package Makefile
\item \texttt{PKG\_BUILD\_DIR} \\
Where to compile the package
\item \texttt{PKG\_SOURCE} \\
The filename of the original sources
\item \texttt{PKG\_SOURCE\_URL} \\
Where to download the sources from
\item \texttt{PKG\_MD5SUM} \\
A checksum to validate the download
\item \texttt{PKG\_CAT} \\
How to decompress the sources (zcat, bzcat, unzip)
\end{itemize}
The \texttt{PKG\_*} variables define where to download the package from;
\texttt{@SF} is a special keyword for downloading packages from sourceforge.
\texttt{@SF} is a special keyword for downloading packages from sourceforge.
The md5sum is used to verify the package was downloaded correctly and
\texttt{PKG\_BUILD\_DIR} defines where to find the package after the sources are
uncompressed into \texttt{\$(BUILD\_DIR)}.
At the bottom of the file is where the real magic happens, "BuildPackage" is a macro
setup by the earlier include statements. BuildPackage only takes one argument directly --
setup by the earlier include statements. BuildPackage only takes one argument directly --
the name of the package to be built, in this case "\texttt{bridge}". All other information
is taken from the define blocks. This is a way of providing a level of verbosity, it's
inherently clear what the contents of the \texttt{description} template in
@ -241,28 +241,28 @@ directly as the Nth argument to \texttt{BuildPackage}.
\texttt{BuildPackage} uses the following defines:
\textbf{\texttt{Package/\textit{<name>}}:} \\
\texttt{\textit{<name>}} matches the argument passed to buildroot, this describes
the package the menuconfig and ipkg entries. Within \texttt{Package/\textit{<name>}}
you can define the following variables:
\texttt{\textit{<name>}} matches the argument passed to buildroot, this describes
the package the menuconfig and ipkg entries. Within \texttt{Package/\textit{<name>}}
you can define the following variables:
\begin{itemize}
\item \texttt{SECTION} \\
The type of package (currently unused)
\item \texttt{CATEGORY} \\
Which menu it appears in menuconfig
\item \texttt{TITLE} \\
A short description of the package
\item \texttt{URL} \\
Where to find the original software
\item \texttt{MAINTAINER} (optional) \\
Who to contact concerning the package
\item \texttt{DEPENDS} (optional) \\
Which packages must be built/installed before this package
\end{itemize}
\begin{itemize}
\item \texttt{SECTION} \\
The type of package (currently unused)
\item \texttt{CATEGORY} \\
Which menu it appears in menuconfig
\item \texttt{TITLE} \\
A short description of the package
\item \texttt{URL} \\
Where to find the original software
\item \texttt{MAINTAINER} (optional) \\
Who to contact concerning the package
\item \texttt{DEPENDS} (optional) \\
Which packages must be built/installed before this package
\end{itemize}
\textbf{\texttt{Package/\textit{<name>}/conffiles} (optional):} \\
A list of config files installed by this package, one file per line.
\textbf{\texttt{Build/Prepare} (optional):} \\
A set of commands to unpack and patch the sources. You may safely leave this
undefined.
@ -279,22 +279,22 @@ directly as the Nth argument to \texttt{BuildPackage}.
\textbf{\texttt{Package/\textit{<name>}/install}:} \\
A set of commands to copy files out of the compiled source and into the ipkg
which is represented by the \texttt{\$(1)} directory.
The reason that some of the defines are prefixed by "\texttt{Package/\textit{<name>}}"
and others are simply "\texttt{Build}" is because of the possibility of generating
multiple packages from a single source. OpenWrt works under the assumption of one
multiple packages from a single source. OpenWrt works under the assumption of one
source per package makefile, but you can split that source into as many packages as
desired. Since you only need to compile the sources once, there's one global set of
desired. Since you only need to compile the sources once, there's one global set of
"\texttt{Build}" defines, but you can add as many "Package/<name>" defines as you want
by adding extra calls to \texttt{BuildPackage} -- see the dropbear package for an example.
After you've created your \texttt{package/\textit{<name>}/Makefile}, the new package
After you've created your \texttt{package/\textit{<name>}/Makefile}, the new package
will automatically show in the menu the next time you run "make menuconfig" and if selected
will be built automatically the next time "\texttt{make}" is run.
\subsubsection{Troubleshooting}
If you find your package doesn't show up in menuconfig, try the following command to
If you find your package doesn't show up in menuconfig, try the following command to
see if you get the correct description:
\begin{Verbatim}
@ -306,15 +306,15 @@ shortcuts you can take. Instead of waiting for make to get to your package, you
run one of the following:
\begin{itemize}
\item \texttt{make package/\textit{<name>}-clean V=99}
\item \texttt{make package/\textit{<name>}-install V=99}
\item \texttt{make package/\textit{<name>}-clean V=99}
\item \texttt{make package/\textit{<name>}-install V=99}
\end{itemize}
Another nice trick is that if the source directory under \texttt{build\_\textit{<arch>}}
is newer than the package directory, it won't clobber it by unpacking the sources again.
If you were working on a patch you could simply edit the sources under the
\texttt{build\_\textit{<arch>}/\textit{<source>}} directory and run the install command above,
when satisfied, copy the patched sources elsewhere and diff them with the unpatched
when satisfied, copy the patched sources elsewhere and diff them with the unpatched
sources. A warning though - if you go modify anything under \texttt{package/\textit{<name>}}
it will remove the old sources and unpack a fresh copy.

22
docs/config.tex
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@ -9,25 +9,25 @@ it was written under.
Syntax:
\begin{Verbatim}
config <type> [<name>] # Section
option <name> <value> # Option
config <type> ["<name>"] # Section
option <name> "<value>" # Option
\end{Verbatim}
Every parameter needs to be a single string and is formatted exactly
like a parameter for a shell function. The same rules for Quoting and
like a parameter for a shell function. The same rules for Quoting and
special characters also apply, as it is parsed by the shell.
\subsubsection{Parsing configuration files in custom scripts}
To be able to load configuration files, you need to include the common
To be able to load configuration files, you need to include the common
functions with:
\begin{Verbatim}
. /etc/functions.sh
\end{Verbatim}
Then you can use \texttt{config\_load \textit{<name>}} to load config files. The function
first checks for \textit{<name>} as absolute filename and falls back to loading
Then you can use \texttt{config\_load \textit{<name>}} to load config files. The function
first checks for \textit{<name>} as absolute filename and falls back to loading
it from \texttt{/etc/config} (which is the most common way of using it).
If you want to use special callbacks for sections and/or options, you
@ -36,13 +36,13 @@ need to define the following shell functions before running \texttt{config\_load
\begin{Verbatim}
config_cb() {
local type="$1"
local name="$2"
# commands to be run for every section
local type="$1"
local name="$2"
# commands to be run for every section
}
option_cb() {
# commands to be run for every option
# commands to be run for every option
}
\end{Verbatim}
@ -68,7 +68,7 @@ config_get <variable> <section> <option> # stores the value inside the variable
In busybox ash the three-option \texttt{config\_get} is faster, because it does not
result in an extra fork, so it is the preferred way.
Additionally you can also modify or add options to sections by using the
Additionally you can also modify or add options to sections by using the
\texttt{config\_set} command.
Syntax:

20
docs/init-scripts.tex
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@ -24,24 +24,24 @@ This is done by the wrapper script \texttt{/etc/rc.common}.
script should provide. \texttt{start()} is called when the user runs \texttt{/etc/init.d/httpd start}
or (if the script is enabled and does not override this behavior) at system boot time.
Enabling and disabling init scripts is done by running \texttt{/etc/init.d/\textit{name} start}
Enabling and disabling init scripts is done by running \texttt{/etc/init.d/\textit{name} start}
or \texttt{/etc/init.d/\textit{name} stop}. This creates or removes symbolic links to the
init script in \texttt{/etc/rc.d}, which is processed by \texttt{/etc/init.d/rcS} at boot time.
The order in which these scripts are run is defined in the variable \texttt{START} in the init
script, which is optional and defaults to \texttt{50}. Changing it requires running
script, which is optional and defaults to \texttt{50}. Changing it requires running
\texttt{/etc/init.d/\textit{name} enable} again.
You can also override these standard init script functions:
\begin{itemize}
\item \texttt{boot()} \\
Commands to be run at boot time. Defaults to \texttt{start()}
\item \texttt{restart()} \\
Restart your service. Defaults to \texttt{stop(); start()}
\item \texttt{reload()} \\
Reload the configuration files for your service. Defaults to \texttt{restart()}
\item \texttt{boot()} \\
Commands to be run at boot time. Defaults to \texttt{start()}
\item \texttt{restart()} \\
Restart your service. Defaults to \texttt{stop(); start()}
\item \texttt{reload()} \\
Reload the configuration files for your service. Defaults to \texttt{restart()}
\end{itemize}

22
docs/network-scripts.tex
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@ -22,13 +22,13 @@ after \texttt{scan\_interfaces} might not return the same result as running it b
After running \texttt{scan\_interfaces}, the following functions are available:
\begin{itemize}
\item{\texttt{find\_config \textit{interface}}} \\
looks for a network configuration that includes
the specified network interface.
\item{\texttt{find\_config \textit{interface}}} \\
looks for a network configuration that includes
the specified network interface.
\item{\texttt{setup\_interface \textit{interface [config] [protocol]}}} \\
will set up the specified interface, optionally overriding the network configuration
name or the protocol that it uses.
\item{\texttt{setup\_interface \textit{interface [config] [protocol]}}} \\
will set up the specified interface, optionally overriding the network configuration
name or the protocol that it uses.
\end{itemize}
\subsubsection{Writing protocol handlers}
@ -38,14 +38,14 @@ You can add custom protocol handlers by adding shell scripts to
\begin{Verbatim}
scan_<protocolname>() {
local config="$1"
# change the interface names if necessary
local config="$1"
# change the interface names if necessary
}
setup_interface_<protocolname>() {
local interface="\$1"
local config="\$2"
# set up the interface
local interface="$1"
local config="$2"
# set up the interface
}
\end{Verbatim}

18
docs/network.tex
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@ -29,7 +29,7 @@ protocol used for the interface. The default image usually provides \texttt{'non
\texttt{'static'}, \texttt{'dhcp'} and \texttt{'pppoe'}. Others can be added by installing additional
packages.
When using the \texttt{'static'} method like in the example, the options \texttt{ipaddr} and
When using the \texttt{'static'} method like in the example, the options \texttt{ipaddr} and
\texttt{netmask} are mandatory, while \texttt{gateway} and \texttt{dns} are optional.
DHCP currently only accepts \texttt{ipaddr} (IP address to request from the server)
and \texttt{hostname} (client hostname identify as) - both are optional.
@ -43,27 +43,27 @@ PPP based protocols (\texttt{pppoe}, \texttt{pptp}, ...) accept these options:
\item{keepalive} \\
Ping the PPP server (using LCP). The value of this option
specifies the maximum number of failed pings before reconnecting.
The ping interval defaults to 5, but can be changed by appending
The ping interval defaults to 5, but can be changed by appending
",<interval>" to the keepalive value
\item{demand} \\
Use Dial on Demand (value specifies the maximum idle time.
\item{server: (pptp)} \\
The remote pptp server IP
\end{itemize}
For all protocol types, you can also specify the MTU by using the \texttt{mtu} option.
\subsubsection{Setting up the switch (currently broadcom only)}
The switch configuration is set by adding a \texttt{'switch'} config section.
Example:
Example:
\begin{Verbatim}
config switch eth0
option vlan0 "1 2 3 4 5*"
option vlan1 "0 5"
config switch "eth0"
option vlan0 "1 2 3 4 5*"
option vlan1 "0 5"
\end{Verbatim}
On Broadcom hardware the section name needs to be eth0, as the switch driver
@ -82,5 +82,5 @@ As value it takes a list of ports with these optional suffixes:
\end{itemize}
The CPU port defaults to tagged, all other ports to untagged.
On Broadcom hardware the CPU port is always 5. The other ports may vary with
On Broadcom hardware the CPU port is always 5. The other ports may vary with
different hardware.

126
docs/wireless.tex
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@ -3,16 +3,16 @@ The WiFi settings are configured in the file \texttt{/etc/config/wireless}
it should detect your card and create a sample configuration that looks like this:
\begin{Verbatim}
config wifi-device wl0
option type broadcom
option channel 5
config wifi-device "wl0"
option type "broadcom"
option channel "5"
config wifi-iface
option device wl0
option mode ap
option ssid OpenWrt
option hidden 0
option encryption none
option device "wl0"
option mode "ap"
option ssid "OpenWrt"
option hidden "0"
option encryption "none"
\end{Verbatim}
There are two types of config sections in this file. The '\texttt{wifi-device}' refers to
@ -22,81 +22,81 @@ of that (if supported by the driver).
\paragraph{Options for the \texttt{wifi-device}:}
\begin{itemize}
\item \texttt{type} \\
The driver to use for this interface.
\item \texttt{country} \\
The country code used to determine the regulatory settings.
\item \texttt{channel} \\
The wifi channel (1-14, depending on your country setting).
\item \texttt{type} \\
The driver to use for this interface.
\item \texttt{maxassoc} \\
Maximum number of associated clients
\item \texttt{country} \\
The country code used to determine the regulatory settings.
\item \texttt{channel} \\
The wifi channel (1-14, depending on your country setting).
\item \texttt{maxassoc} \\
Maximum number of associated clients
\end{itemize}
\paragraph{Options for the \texttt{wifi-iface}:}
\begin{itemize}
\item \texttt{mode} \\
Operating mode:
\begin{itemize}
\item \texttt{ap} \\
Access point mode
\item \texttt{mode} \\
Operating mode:
\item \texttt{sta} \\
Client mode
\begin{itemize}
\item \texttt{ap} \\
Access point mode
\item \texttt{adhoc} \\
Ad-Hoc mode
\item \texttt{sta} \\
Client mode
\item \texttt{wds} \\
WDS point-to-point link
\end{itemize}
\item \texttt{network} \\
Selects the interface section from \texttt{/etc/config/network} to be
used with this interface
\item \texttt{adhoc} \\
Ad-Hoc mode
\item \texttt{encryption} \\
Encryption setting. Accepts the following values:
\begin{itemize}
\item \texttt{psk}, \texttt{psk2} \\
WPA(2) Pre-shared Key
\item \texttt{wpa}, \texttt{wpa2} \\
WPA(2) RADIUS
\end{itemize}
\item \texttt{key} (wpa and psk) \\
Either the WPA key (PSK mode) or the RADIUS shared secret (WPA RADIUS mode)
\item \texttt{wds} \\
WDS point-to-point link
\item \texttt{server} (wpa) \\
The RADIUS server address
\end{itemize}
\item \texttt{network} \\
Selects the interface section from \texttt{/etc/config/network} to be
used with this interface
\item \texttt{port} (wpa) \\
The RADIUS server port
\item \texttt{encryption} \\
Encryption setting. Accepts the following values:
\begin{itemize}
\item \texttt{psk}, \texttt{psk2} \\
WPA(2) Pre-shared Key
\item \texttt{wpa}, \texttt{wpa2} \\
WPA(2) RADIUS
\end{itemize}
\item \texttt{key} (wpa and psk) \\
Either the WPA key (PSK mode) or the RADIUS shared secret (WPA RADIUS mode)
\item \texttt{server} (wpa) \\
The RADIUS server address
\item \texttt{port} (wpa) \\
The RADIUS server port
\end{itemize}
\paragraph{Limitations:}
\begin{itemize}
\item \textbf{Broadcom}: \\
Only the following mode combinations are supported:
\begin{itemize}
\item 1x \texttt{sta}, 0-3x \texttt{ap}
\item 1-4x \texttt{ap}
\item 1x \texttt{adhoc}
\end{itemize}
\item \textbf{Broadcom}: \\
Only the following mode combinations are supported:
WDS links can only be used in pure AP mode and can't use WEP (except when sharing the
settings with the master interface, which is done automatically).
\begin{itemize}
\item 1x \texttt{sta}, 0-3x \texttt{ap}
\item 1-4x \texttt{ap}
\item 1x \texttt{adhoc}
\end{itemize}
WDS links can only be used in pure AP mode and can't use WEP (except when sharing the
settings with the master interface, which is done automatically).
\end{itemize}