Xorg
supports several mechanisms for supplying/obtaining configuration and
run-time parameters: command line options, environment variables, the
xorg.conf configuration file, auto-detection, and fallback defaults.
When the same information is supplied in more than one way, the highest
precedence mechanism is used. The list of mechanisms is ordered from
highest precedence to lowest. Note that not all parameters can be
supplied via all methods. The available command line options and
environment variables (and some defaults) are described in the Xserver(1)
and Xorg(1) manual pages. Most configuration file parameters, with
their defaults, are described below. Driver and module specific
configuration parameters are described in the relevant driver or module
manual page.
DESCRIPTION
Xorg
uses a configuration file called
xorg.conf
for its initial setup.
This configuration file is searched for in the following places when the
server is started as a normal user:
where
<cmdline>
is a relative path (with no lq..rq components) specified with the
-config
command line option,
$XORGCONFIG
is the relative path (with no lq..rq components) specified by that
environment variable, and
<hostname>
is the machine's hostname as reported by
gethostname(__oslibmansuffix__).
When the Xorg server is started by the lqrootrq user, the config file
search locations are as follows:
where
<cmdline>
is the path specified with the
-config
command line option (which may be absolute or relative),
$XORGCONFIG
is the path specified by that
environment variable (absolute or relative),
$HOME
is the path specified by that environment variable (usually the home
directory), and
<hostname>
is the machine's hostname as reported by
gethostname(__oslibmansuffix__).
The
xorg.conf
file is composed of a number of sections which may be present in any order.
Each section has the form:
The following obsolete section names are still recognised for compatibility
purposes.
In new config files, the
InputDevice
section should be used instead.
The
ServerLayout
sections are at the highest level.
They bind together the input and output devices that will be used in a session.
The input devices are described in the
InputDevice
sections.
Output devices usually consist of multiple independent components (e.g.,
a graphics board and a monitor).
These multiple components are bound together in the
Screen
sections, and it is these that are referenced by the
ServerLayout
section.
Each
Screen
section binds together a graphics board and a monitor.
The graphics boards are described in the
Device
sections, and the monitors are described in the
Monitor
sections.
Config file keywords are case-insensitive, and lq_rq characters are
ignored.
Most strings (including
Option
names) are also case-insensitive, and insensitive to white space and
lq_rq characters.
Each config file entry usually takes up a single line in the file. They
consist of a keyword, which is possibly followed by one or more arguments,
with the number and types of the arguments depending on the keyword.
The argument types are:
Integer an integer number in decimal, hex or octal
Real a floating point number
String a string enclosed in double quote marks (N'34')
Note: hex integer values must be prefixed with lq0xrq, and octal values
with lq0rq.
A special keyword called
Option
may be used to provide free-form data to various components of the server.
The
Option
keyword takes either one or two string arguments.
The first is the option name, and the optional second argument is the
option value.
Some commonly used option value types include:
Integer an integer number in decimal, hex or octal
Real a floating point number
String a sequence of characters
Boolean a boolean value (see below)
Frequency a frequency value (see below)
Note that
allOption
values, not just strings, must be enclosed in quotes.
Boolean options may optionally have a value specified.
When no value is specified, the option's value is
TRUE.
The following boolean option values are recognised as
TRUE:
1,
on,
true,
yes
and the following boolean option values are recognised as
FALSE:
0,
off,
false,
no
If an option name is prefixed with
N'34'NoN'34',
then the option value is negated.
Example: the following option entries are equivalent:
Frequency option values consist of a real number that is optionally
followed by one of the following frequency units:
Hz,
k,
kHz,
M,
MHz
When the unit name is omitted, the correct units will be determined from
the value and the expectations of the appropriate range of the value.
It is recommended that the units always be specified when using frequency
option values to avoid any errors in determining the value.
FILES SECTION
The
Files
section is used to specify some path names required by the server.
Some of these paths can also be set from the command line (see
Xserver(1)
and
Xorg(1)).
The command line settings override the values specified in the config
file.
The
Files
section is optional, as are all of the entries that may appear in it.
The entries that can appear in this section are:
FontPath N'34'pathN'34'
sets the search path for fonts.
This path is a comma separated list of font path elements which the Xorg
server searches for font databases.
Multiple
FontPath
entries may be specified, and they will be concatenated to build up the
fontpath used by the server. Font path elements may be either absolute
directory paths, or a font server identifier.
Font server identifiers have the form:
<trans>/<hostname>:<port-number>
where
<trans>
is the transport type to use to connect to the font server (e.g.,
unix
for UNIX-domain sockets or
tcp
for a TCP/IP connection),
<hostname>
is the hostname of the machine running the font server, and
<port-number>
is the port number that the font server is listening on (usually 7100).
When this entry is not specified in the config file, the server falls back
to the compiled-in default font path, which contains the following
font path elements:
Font path elements that are found to be invalid are removed from the
font path when the server starts up.
RGBPath N'34'pathN'34'
sets the path name for the RGB color database.
When this entry is not specified in the config file, the server falls back
to the compiled-in default RGB path, which is:
/usr/share/X11/rgb
Note that an implicit
.txt
is added to this path if the server was compiled to use text rather than
binary format RGB color databases.
ModulePath N'34'pathN'34'
sets the search path for loadable Xorg server modules.
This path is a comma separated list of directories which the Xorg server
searches for loadable modules loading in the order specified.
Multiple
ModulePath
entries may be specified, and they will be concatenated to build the
module search path used by the server.
SERVERFLAGS SECTION
In addition to options specific to this section (described below), the
ServerFlags
section is used to specify some global
Xorg server options.
All of the entries in this section are
Options,
although for compatibility purposes some of the old style entries are
still recognised.
Those old style entries are not documented here, and using them is
discouraged.
The
ServerFlags
section is optional, as are the entries that may be specified in it.
Options
specified in this section (with the exception of the
N'34'DefaultServerLayoutN'34'Option)
may be overridden by
Options
specified in the active
ServerLayout
section.
Options with command line equivalents are overridden when their command
line equivalent is used.
The options recognised by this section are:
This specifies the default
ServerLayout
section to use in the absence of the
-layout
command line option.
Option N'34'NoTrapSignalsN'34' N'34'booleanN'34'
This prevents the Xorg server from trapping a range of unexpected fatal
signals and exiting cleanly.
Instead, the Xorg server will die and drop core where the fault occurred.
The default behaviour is for the Xorg server to exit cleanly, but still drop a
core file.
In general you never want to use this option unless you are debugging an Xorg
server problem and know how to deal with the consequences.
Option N'34'DontVTSwitchN'34' N'34'booleanN'34'
This disallows the use of the
Ctrl+Alt+Fn
sequence (where
Fn
refers to one of the numbered function keys).
That sequence is normally used to switch to another N'34'virtual terminalN'34'
on operating systems that have this feature.
When this option is enabled, that key sequence has no special meaning and
is passed to clients.
Default: off.
Option N'34'DontZapN'34' N'34'booleanN'34'
This disallows the use of the
Ctrl+Alt+Backspace
sequence.
That sequence is normally used to terminate the Xorg server.
When this option is enabled, that key sequence has no special meaning and
is passed to clients.
Default: off.
Option N'34'DontZoomN'34' N'34'booleanN'34'
This disallows the use of the
Ctrl+Alt+Keypad-Plus
and
Ctrl+Alt+Keypad-Minus
sequences.
These sequences allows you to switch between video modes.
When this option is enabled, those key sequences have no special meaning
and are passed to clients.
Default: off.
This disables the parts of the VidMode extension used by the xvidtune client
that can be used to change the video modes.
Default: the VidMode extension is enabled.
This disables the parts of the Xorg-Misc extension that can be used to
modify the input device settings dynamically.
Default: that functionality is enabled.
This allows the server to start up even if the mouse device can't be
opened/initialised.
Default: false.
Option N'34'VTInitN'34' N'34'commandN'34'
Runs
command
after the VT used by the server has been opened.
The command string is passed to N'34'/bin/sh -cN'34', and is run with the real
user's id with stdin and stdout set to the VT.
The purpose of this option is to allow system dependent VT initialisation
commands to be run.
This option should rarely be needed.
Default: not set.
Option N'34'VTSysReqN'34' N'34'booleanN'34'
enables the SYSV-style VT switch sequence for non-SYSV systems
which support VT switching.
This sequence is
Alt-SysRq
followed by a function key
(Fn).
This prevents the Xorg server trapping the
keys used for the default VT switch sequence, which means that clients can
access them.
Default: off.
Option N'34'XkbDisableN'34' N'34'booleanN'34'
disable/enable the XKEYBOARD extension.
The -kb command line option overrides this config file option.
Default: XKB is enabled.
Option N'34'BlankTimeN'34' N'34'timeN'34'
sets the inactivity timeout for the
blank
phase of the screensaver.
time
is in minutes.
This is equivalent to the Xorg server's
-s
flag, and the value can be changed at run-time with
xset(1).
Default: 10 minutes.
Option N'34'StandbyTimeN'34' N'34'timeN'34'
sets the inactivity timeout for the
standby
phase of DPMS mode.
time
is in minutes, and the value can be changed at run-time with
xset(1).
Default: 20 minutes.
This is only suitable for VESA DPMS compatible monitors, and may not be
supported by all video drivers.
It is only enabled for screens that have the
N'34'DPMSN'34'
option set (see the MONITOR section below).
Option N'34'SuspendTimeN'34' N'34'timeN'34'
sets the inactivity timeout for the
suspend
phase of DPMS mode.
time
is in minutes, and the value can be changed at run-time with
xset(1).
Default: 30 minutes.
This is only suitable for VESA DPMS compatible monitors, and may not be
supported by all video drivers.
It is only enabled for screens that have the
N'34'DPMSN'34'
option set (see the MONITOR section below).
Option N'34'OffTimeN'34' N'34'timeN'34'
sets the inactivity timeout for the
off
phase of DPMS mode.
time
is in minutes, and the value can be changed at run-time with
xset(1).
Default: 40 minutes.
This is only suitable for VESA DPMS compatible monitors, and may not be
supported by all video drivers.
It is only enabled for screens that have the
N'34'DPMSN'34'
option set (see the MONITOR section below).
Option N'34'PixmapN'34' N'34'bppN'34'
This sets the pixmap format to use for depth 24.
Allowed values for
bpp
are 24 and 32.
Default: 32 unless driver constraints don't allow this (which is rare).
Note: some clients don't behave well when this value is set to 24.
Option N'34'PC98N'34' N'34'booleanN'34'
Specify that the machine is a Japanese PC-98 machine.
This should not be enabled for anything other than the Japanese-specific
PC-98 architecture.
Default: auto-detected.
Option N'34'NoPMN'34' N'34'booleanN'34'
Disables something to do with power management events.
Default: PM enabled on platforms that support it.
Option N'34'XineramaN'34' N'34'booleanN'34'
enable or disable XINERAMA extension.
Default is disabled.
This option enables the use of the
Ctrl+Alt+Keypad-Multiply
key sequence to kill clients with an active keyboard or mouse grab as well
as killing any application that may have locked the server, normally using
the
XGrabServer(3)
Xlib function.
Default: off.
Note that the options
AllowDeactivateGrabs
and
AllowClosedownGrabs
will allow users to remove the grab used by screen saver/locker programs.
An API was written to such cases.
If you enable this option, make sure your screen saver/locker is updated.
Default: off.
Option N'34'HandleSpecialKeysN'34' N'34'whenN'34'
This option controls when the server uses the builtin handler to process
special key combinations (such as
Ctrl+Alt+Backspace).
Normally the XKEYBOARD extension keymaps will provide mappings for each of
the special key combinations, so the builtin handler is not needed unless
the XKEYBOARD extension is disabled.
The value of
when
can be
Always,
Never,
or
WhenNeeded.
Default: Use the builtin handler only if needed.
The server will scan the keymap for a mapping to the
Terminate
action and, if found, use XKEYBOARD for processing actions, otherwise
the builtin handler will be used.
Option N'34'AIGLXN'34' N'34'booleanN'34'
enable or disable AIGLX. AIGLX is enabled by default.
Include the default font path even if other paths are specified in
xorg.conf. If enabled, other font paths are included as well. Enabled by
default.
Option N'34'IgnoreABIN'34' N'34'booleanN'34'
Allow modules built for a different, potentially incompatible version of
the X server to load. Disabled by default.
MODULE SECTION
The
Module
section is used to specify which Xorg server modules should be loaded.
This section is ignored when the Xorg server is built in static form.
The types of modules normally loaded in this section are Xorg server
extension modules, and font rasteriser modules.
Most other module types are loaded automatically when they are needed via
other mechanisms.
The
Module
section is optional, as are all of the entries that may be specified in
it.
Entries in this section may be in two forms.
The first and most commonly used form is an entry that uses the
Load
keyword, as described here:
Load N'34'modulenameN'34'
This instructs the server to load the module called
modulename.
The module name given should be the module's standard name, not the
module file name.
The standard name is case-sensitive, and does not include the lqlibrq
prefix, or the lq.arq, lq.orq, or lq.sorq suffixes.
Example: the Type 1 font rasteriser can be loaded with the following entry:
Load N'34'type1N'34'
Disable N'34'modulenameN'34'
This instructs the server to not load the module called
modulename.
Some modules are loaded by default in the server, and this overrides that
default. If a
Load
instruction is given for the same module, it overrides the
Disable
instruction and the module is loaded. The module name given should be the
module's standard name, not the module file name. As with the
Load
instruction, the standard name is case-sensitive, and does not include the
"lib" prefix, or the ".a", ".o", or ".so" suffixes.
The second form of entry is a
SubSection,
with the subsection name being the module name, and the contents of the
SubSection
being
Options
that are passed to the module when it is loaded.
Example: the extmod module (which contains a miscellaneous group of
server extensions) can be loaded, with the XFree86-DGA extension
disabled by using the following entry:
Modules are searched for in each directory specified in the
ModulePath
search path, and in the drivers, input, extensions, fonts, and
internal subdirectories of each of those directories.
In addition to this, operating system specific subdirectories of all
the above are searched first if they exist.
To see what font and extension modules are available, check the contents
of the following directories:
The lqbitmaprq font module is loaded automatically.
It is recommended
that at very least the lqextmodrq extension module be loaded.
If it isn't, some commonly used server extensions (like the SHAPE
extension) will not be available.
INPUTDEVICE SECTION
The config file may have multiple
InputDevice
sections.
There will normally be at least two: one for the core (primary) keyboard,
and one of the core pointer.
If either of these two is missing, a default configuration for the missing
ones will be used.
Currently the default configuration may not work as expected on all platforms.
The
Identifier
and
Driver
entries are required in all
InputDevice
sections.
All other entries are optional.
The
Identifier
entry specifies the unique name for this input device.
The
Driver
entry specifies the name of the driver to use for this input device.
When using the loadable server, the input driver module
N'34'inputdriverN'34'
will be loaded for each active
InputDevice
section.
An
InputDevice
section is considered active if it is referenced by an active
ServerLayout
section, if it is referenced by the
-keyboard
or
-pointer
command line options, or if it is selected implicitly as the core pointer
or keyboard device in the absence of such explicit references.
The most commonly used input drivers are
keyboard(4)
and
mouse(4).
In the absence of an explicitly specified core input device, the first
InputDevice
marked as
CorePointer
(or
CoreKeyboard)
is used.
If there is no match there, the first
InputDevice
that uses the lqmouserq (or lqkeyboardrq or lqkbdrq) driver is used.
The final fallback is to use built-in default configurations.
InputDevice
sections recognise some driver-independent
Options,
which are described here.
See the individual input driver manual pages for a description of the
device-specific options.
Option N'34'CorePointerN'34'
When this is set, the input device is installed as the core (primary)
pointer device.
There must be exactly one core pointer.
If this option is not set here, or in the
ServerLayout
section, or from the
-pointer
command line option, then the first input device that is capable of
being used as a core pointer will be selected as the core pointer.
This option is implicitly set when the obsolete
Pointer
section is used.
Option N'34'CoreKeyboardN'34'
When this is set, the input device is to be installed as the core
(primary) keyboard device.
There must be exactly one core keyboard.
If this option is not set here, in the
ServerLayout
section, or from the
-keyboard
command line option, then the first input device that is capable of
being used as a core keyboard will be selected as the core keyboard.
This option is implicitly set when the obsolete
Keyboard
section is used.
Option N'34'AlwaysCoreN'34' N'34'booleanN'34'
Option N'34'SendCoreEventsN'34' N'34'booleanN'34'
Both of these options are equivalent, and when enabled cause the
input device to always report core events.
This can be used, for example, to allow an additional pointer device to
generate core pointer events (like moving the cursor, etc).
Option N'34'HistorySizeN'34' N'34'numberN'34'
Sets the motion history size.
Default: 0.
Option N'34'SendDragEventsN'34' N'34'booleanN'34'
???
DEVICE SECTION
The config file may have multiple
Device
sections.
There must be at least one, for the video card being used.
The
Identifier
and
Driver
entries are required in all
Device
sections. All other entries are optional.
The
Identifier
entry specifies the unique name for this graphics device.
The
Driver
entry specifies the name of the driver to use for this graphics device.
When using the loadable server, the driver module
N'34'driverN'34'
will be loaded for each active
Device
section.
A
Device
section is considered active if it is referenced by an active
Screen
section.
Device
sections recognise some driver-independent entries and
Options,
which are described here.
Not all drivers make use of these
driver-independent entries, and many of those that do don't require them
to be specified because the information is auto-detected.
See the individual graphics driver manual pages for further information
about this, and for a description of the device-specific options.
Note that most of the
Options
listed here (but not the other entries) may be specified in the
Screen
section instead of here in the
Device
section.
BusID N'34'bus-idN'34'
This specifies the bus location of the graphics card.
For PCI/AGP cards,
the
bus-id
string has the form
PCI:bus:device:function
(e.g., lqPCI:1:0:0rq might be appropriate for an AGP card).
This field is usually optional in single-head configurations when using
the primary graphics card.
In multi-head configurations, or when using a secondary graphics card in a
single-head configuration, this entry is mandatory.
Its main purpose is to make an unambiguous connection between the device
section and the hardware it is representing.
This information can usually be found by running the Xorg server
with the
-scanpci
command line option.
Screen number
This option is mandatory for cards where a single PCI entity can drive more
than one display (i.e., multiple CRTCs sharing a single graphics accelerator
and video memory).
One
Device
section is required for each head, and this
parameter determines which head each of the
Device
sections applies to.
The legal values of
number
range from 0 to one less than the total number of heads per entity.
Most drivers require that the primary screen (0) be present.
Chipset N'34'chipsetN'34'
This usually optional entry specifies the chipset used on the graphics
board.
In most cases this entry is not required because the drivers will probe the
hardware to determine the chipset type.
Don't specify it unless the driver-specific documentation recommends that you
do.
Ramdac N'34'ramdac-typeN'34'
This optional entry specifies the type of RAMDAC used on the graphics
board.
This is only used by a few of the drivers, and in most cases it is not
required because the drivers will probe the hardware to determine the
RAMDAC type where possible.
Don't specify it unless the driver-specific documentation recommends that you
do.
DacSpeed speed
DacSpeed speed-8 speed-16 speed-24 speed-32
This optional entry specifies the RAMDAC speed rating (which is usually
printed on the RAMDAC chip).
The speed is in MHz.
When one value is given, it applies to all framebuffer pixel sizes.
When multiple values are given, they apply to the framebuffer pixel sizes
8, 16, 24 and 32 respectively.
This is not used by many drivers, and only needs to be specified when the
speed rating of the RAMDAC is different from the defaults built in to
driver, or when the driver can't auto-detect the correct defaults.
Don't specify it unless the driver-specific documentation recommends that you
do.
Clocks clock ...
specifies the pixel that are on your graphics board.
The clocks are in MHz, and may be specified as a floating point number.
The value is stored internally to the nearest kHz.
The ordering of the clocks is important.
It must match the order in which they are selected on the graphics board.
Multiple
Clocks
lines may be specified, and each is concatenated to form the list.
Most drivers do not use this entry, and it is only required for some older
boards with non-programmable clocks.
Don't specify this entry unless the driver-specific documentation explicitly
recommends that you do.
ClockChip N'34'clockchip-typeN'34'
This optional entry is used to specify the clock chip type on graphics
boards which have a programmable clock generator.
Only a few Xorg drivers support programmable clock chips.
For details, see the appropriate driver manual page.
VideoRam mem
This optional entry specifies the amount of video ram that is installed
on the graphics board.
This is measured in kBytes.
In most cases this is not required because the Xorg server probes
the graphics board to determine this quantity.
The driver-specific documentation should indicate when it might be needed.
BiosBase baseaddress
This optional entry specifies the base address of the video BIOS for
the VGA board.
This address is normally auto-detected, and should only be specified if the
driver-specific documentation recommends it.
MemBase baseaddress
This optional entry specifies the memory base address of a graphics
board's linear frame buffer.
This entry is not used by many drivers, and it should only be specified if
the driver-specific documentation recommends it.
IOBase baseaddress
This optional entry specifies the IO base address.
This entry is not used by many drivers, and it should only be specified if
the driver-specific documentation recommends it.
ChipID id
This optional entry specifies a numerical ID representing the chip type.
For PCI cards, it is usually the device ID.
This can be used to override the auto-detection, but that should only be done
when the driver-specific documentation recommends it.
ChipRev rev
This optional entry specifies the chip revision number.
This can be used to override the auto-detection, but that should only be done
when the driver-specific documentation recommends it.
TextClockFreq freq
This optional entry specifies the pixel clock frequency that is used
for the regular text mode.
The frequency is specified in MHz.
This is rarely used.
Option N'34'ModeDebugN'34' N'34'booleanN'34'
Enable printing of additional debugging information about modesetting to
the server log.
Options
Option flags may be specified in the
Device
sections.
These include driver-specific options and driver-independent options.
The former are described in the driver-specific documentation.
Some of the latter are described below in the section about the
Screen
section, and they may also be included here.
VIDEOADAPTOR SECTION
Nobody wants to say how this works.
Maybe nobody knows ...
MONITOR SECTION
The config file may have multiple
Monitor
sections.
There should normally be at least one, for the monitor being used,
but a default configuration will be created when one isn't specified.
The only mandatory entry in a
Monitor
section is the
Identifier
entry.
The
Identifier
entry specifies the unique name for this monitor.
The
Monitor
section may be used to provide information about the specifications of the
monitor, monitor-specific
Options,
and information about the video modes to use with the monitor.
With RandR 1.2-enabled drivers, monitor sections may be tied to specific
outputs of the video card. Using the name of the output defined by the video
driver plus the identifier of a monitor section, one associates a monitor
section with an output by adding an option to the Device section in the
following format:
(for example,
Option N'34'Monitor-VGAN'34' N'34'VGA monitorN'34'
for a VGA output)
In the absence of specific association of monitor sections to outputs, if a
monitor section is present the server will associate it with an output to
preserve compatibility for previous single-head configurations.
Specifying video modes is optional because the server will use the DDC or other
information provided by the monitor to automatically configure the list of
modes available.
When modes are specified explicitly in the
Monitor
section (with the
Modes,
ModeLine,
or
UseModes
keywords), built-in modes with the same names are not included.
Built-in modes with different names are, however, still implicitly included,
when they meet the requirements of the monitor.
The entries that may be used in
Monitor
sections are described below.
VendorName N'34'vendorN'34'
This optional entry specifies the monitor's manufacturer.
ModelName N'34'modelN'34'
This optional entry specifies the monitor's model.
HorizSync horizsync-range
gives the range(s) of horizontal sync frequencies supported by the
monitor.
horizsync-range
may be a comma separated list of either discrete values or ranges of
values.
A range of values is two values separated by a dash.
By default the values are in units of kHz.
They may be specified in MHz or Hz
if
MHz
or
Hz
is added to the end of the line.
The data given here is used by the Xorg server to determine if video
modes are within the specifications of the monitor.
This information should be available in the monitor's handbook.
If this entry is omitted, a default range of 28-33kHz is used.
VertRefresh vertrefresh-range
gives the range(s) of vertical refresh frequencies supported by the
monitor.
vertrefresh-range
may be a comma separated list of either discrete values or ranges of
values.
A range of values is two values separated by a dash.
By default the values are in units of Hz.
They may be specified in MHz or kHz
if
MHz
or
kHz
is added to the end of the line.
The data given here is used by the Xorg server to determine if video
modes are within the specifications of the monitor.
This information should be available in the monitor's handbook.
If this entry is omitted, a default range of 43-72Hz is used.
DisplaySize width height
This optional entry gives the width and height, in millimetres, of the
picture area of the monitor.
If given this is used to calculate the horizontal and vertical pitch (DPI) of
the screen.
Gamma gamma-value
Gamma red-gamma green-gamma blue-gamma
This is an optional entry that can be used to specify the gamma correction
for the monitor.
It may be specified as either a single value or as three separate RGB values.
The values should be in the range 0.1 to 10.0, and the default is 1.0.
Not all drivers are capable of using this information.
UseModes N'34'modesection-idN'34'
Include the set of modes listed in the
Modes
section called
modesection-id.
This makes all of the modes defined in that section available for use by
this monitor.
Mode N'34'nameN'34'
This is an optional multi-line entry that can be used to provide
definitions for video modes for the monitor.
In most cases this isn't necessary because the built-in set of VESA standard
modes will be sufficient.
The
Mode
keyword indicates the start of a multi-line video mode description.
The mode description is terminated with the
EndMode
keyword.
The mode description consists of the following entries:
DotClock clock
is the dot (pixel) clock rate to be used for the mode.
HTimings hdisp hsyncstart hsyncend htotal
specifies the horizontal timings for the mode.
VTimings vdisp vsyncstart vsyncend vtotal
specifies the vertical timings for the mode.
Flags N'34'flagN'34' ...
specifies an optional set of mode flags, each of which is a separate
string in double quotes.
N'34'InterlaceN'34'
indicates that the mode is interlaced.
N'34'DoubleScanN'34'
indicates a mode where each scanline is doubled.
N'34'+HSyncN'34'
and
N'34'-HSyncN'34'
can be used to select the polarity of the HSync signal.
N'34'+VSyncN'34'
and
N'34'-VSyncN'34'
can be used to select the polarity of the VSync signal.
N'34'CompositeN'34'
can be used to specify composite sync on hardware where this is supported.
Additionally, on some hardware,
N'34'+CSyncN'34'
and
N'34'-CSyncN'34'
may be used to select the composite sync polarity.
HSkew hskew
specifies the number of pixels (towards the right edge of the screen) by
which the display enable signal is to be skewed.
Not all drivers use this information.
This option might become necessary to override the default value supplied
by the server (if any).
lqRovingrq horizontal lines indicate this value needs to be increased.
If the last few pixels on a scan line appear on the left of the screen,
this value should be decreased.
VScan vscan
specifies the number of times each scanline is painted on the screen.
Not all drivers use this information.
Values less than 1 are treated as 1, which is the default.
Generally, the
N'34'DoubleScanN'34'Flag
mentioned above doubles this value.
ModeLine N'34'nameN'34' mode-description
This entry is a more compact version of the
Mode
entry, and it also can be used to specify video modes for the monitor.
is a single line format for specifying video modes.
In most cases this isn't necessary because the built-in set of VESA
standard modes will be sufficient.
The
mode-description
is in four sections, the first three of which are mandatory.
The first is the dot (pixel) clock.
This is a single number specifying the pixel clock rate for the mode in
MHz.
The second section is a list of four numbers specifying the horizontal
timings.
These numbers are the
hdisp,
hsyncstart,
hsyncend,
and
htotal
values.
The third section is a list of four numbers specifying the vertical
timings.
These numbers are the
vdisp,
vsyncstart,
vsyncend,
and
vtotal
values.
The final section is a list of flags specifying other characteristics of
the mode.
Interlace
indicates that the mode is interlaced.
DoubleScan
indicates a mode where each scanline is doubled.
+HSync
and
-HSync
can be used to select the polarity of the HSync signal.
+VSync
and
-VSync
can be used to select the polarity of the VSync signal.
Composite
can be used to specify composite sync on hardware where this is supported.
Additionally, on some hardware,
+CSync
and
-CSync
may be used to select the composite sync polarity.
The
HSkew
and
VScan
options mentioned above in the
Modes
entry description can also be used here.
Option N'34'DPMSN'34' N'34'boolN'34'
This option controls whether the server should enable the DPMS extension
for power management for this screen. The default is to enable the
extension.
Option N'34'SyncOnGreenN'34' N'34'boolN'34'
This option controls whether the video card should drive the sync signal
on the green color pin. Not all cards support this option, and most
monitors do not require it. The default is off.
Option N'34'TargetRefreshN'34' N'34'rateN'34'
This optional entry specifies the vertical refresh rate that the server
should aim for when selecting video modes. Without this option, the
default is to prefer modes with higher refresh rates.
Option N'34'PreferredModeN'34' N'34'stringN'34'
This optional entry specifies a mode to be marked as the preferred initial mode
of the monitor.
(RandR 1.2-supporting drivers only)
Option N'34'PositionN'34' N'34'x yN'34'
This optional entry specifies the position of the monitor within the X
screen.
(RandR 1.2-supporting drivers only)
Option N'34'LeftOfN'34' N'34'monitorN'34'
This optional entry specifies that the monitor should be positioned to the
left of the monitor of the given name.
(RandR 1.2-supporting drivers only)
Option N'34'RightOfN'34' N'34'monitorN'34'
This optional entry specifies that the monitor should be positioned to the
right of the monitor of the given name.
(RandR 1.2-supporting drivers only)
Option N'34'AboveN'34' N'34'monitorN'34'
This optional entry specifies that the monitor should be positioned above the
monitor of the given name.
(RandR 1.2-supporting drivers only)
Option N'34'BelowN'34' N'34'monitorN'34'
This optional entry specifies that the monitor should be positioned below the
monitor of the given name.
(RandR 1.2-supporting drivers only)
Option N'34'EnableN'34' N'34'boolN'34'
This optional entry specifies whether the monitor should be turned on
at startup. By default, the server will attempt to enable all connected
monitors.
(RandR 1.2-supporting drivers only)
Option N'34'MinClockN'34' N'34'frequencyN'34'
This optional entry specifies the minimum dot clock, in kHz, that is supported
by the monitor.
Option N'34'MaxClockN'34' N'34'frequencyN'34'
This optional entry specifies the maximum dot clock, in kHz, that is supported
by the monitor.
Option N'34'IgnoreN'34' N'34'boolN'34'
This optional entry specifies that the monitor should be ignored entirely,
and not reported through RandR. This is useful if the hardware reports the
presence of outputs that don't exist.
(RandR 1.2-supporting drivers only)
Option N'34'RotateN'34' N'34'rotationN'34'
This optional entry specifies the initial rotation of the given monitor.
Valid values for rotation are N'34'normalN'34', N'34'leftN'34', N'34'rightN'34', and
N'34'invertedN'34'.
(RandR 1.2-supporting drivers only)
MODES SECTION
The config file may have multiple
Modes
sections, or none.
These sections provide a way of defining sets of video modes independently
of the
Monitor
sections.
Monitor
sections may include the definitions provided in these sections by
using the
UseModes
keyword.
In most cases the
Modes
sections are not necessary because the built-in set of VESA standard modes
will be sufficient.
The
Identifier
entry specifies the unique name for this set of mode descriptions.
The other entries permitted in
Modes
sections are the
Mode
and
ModeLine
entries that are described above in the
Monitor
section.
SCREEN SECTION
The config file may have multiple
Screen
sections.
There must be at least one, for the lqscreenrq being used.
A lqscreenrq represents the binding of a graphics device
(Device
section) and a monitor
(Monitor
section).
A
Screen
section is considered lqactiverq if it is referenced by an active
ServerLayout
section or by the
-screen
command line option.
If neither of those is present, the first
Screen
section found in the config file is considered the active one.
The
Identifier
and
Device
entries are mandatory.
All others are optional.
The
Identifier
entry specifies the unique name for this screen.
The
Screen
section provides information specific to the whole screen, including
screen-specific
Options.
In multi-head configurations, there will be multiple active
Screen
sections, one for each head.
The entries available
for this section are:
Device N'34'device-idN'34'
This mandatory entry specifies the
Device
section to be used for this screen.
This is what ties a specific graphics card to a screen.
The
device-id
must match the
Identifier
of a
Device
section in the config file.
Monitor N'34'monitor-idN'34'
specifies which monitor description is to be used for this screen.
If a
Monitor
name is not specified, a default configuration is used.
Currently the default configuration may not function as expected on all
platforms.
VideoAdaptor N'34'xv-idN'34'
specifies an optional Xv video adaptor description to be used with this
screen.
DefaultDepth depth
specifies which color depth the server should use by default.
The
-depth
command line option can be used to override this.
If neither is specified, the default depth is driver-specific, but in most
cases is 8.
DefaultFbBpp bpp
specifies which framebuffer layout to use by default.
The
-fbbpp
command line option can be used to override this.
In most cases the driver will chose the best default value for this.
The only case where there is even a choice in this value is for depth 24,
where some hardware supports both a packed 24 bit framebuffer layout and a
sparse 32 bit framebuffer layout.
Options
Various
Option
flags may be specified in the
Screen
section.
Some are driver-specific and are described in the driver documentation.
Others are driver-independent, and will eventually be described here.
Option N'34'AccelN'34'
Enables XAA (X Acceleration Architecture), a mechanism that makes video
cards' 2D hardware acceleration available to the __xservername__ server.
This option is on by default, but it may be necessary to turn it off if
there are bugs in the driver.
There are many options to disable specific accelerated operations, listed
below.
Note that disabling an operation will have no effect if the operation is
not accelerated (whether due to lack of support in the hardware or in the
driver).
Option N'34'BiosLocationN'34' N'34'addressN'34'
Set the location of the BIOS for the Int10 module. One may select a BIOS
of another card for posting or the legacy V_BIOS range located at 0xc0000
or an alternative address (BUS_ISA).
This is only useful under very special circumstances and should be used with
extreme care.
Option N'34'InitPrimaryN'34' N'34'booleanN'34'
Use the Int10 module to initialize the primary graphics card.
Normally, only secondary cards are soft-booted using the Int10 module, as the
primary card has already been initialized by the BIOS at boot time.
Default: false.
Option N'34'NoInt10N'34' N'34'booleanN'34'
Disables the Int10 module, a module that uses the int10 call to the BIOS
of the graphics card to initialize it.
Default: false.
Option N'34'NoMTRRN'34'
Disables MTRR (Memory Type Range Register) support, a feature of modern
processors which can improve video performance by a factor of up to 2.5.
Some hardware has buggy MTRR support, and some video drivers have been
known to exhibit problems when MTRR's are used.
Option N'34'XaaNoCPUToScreenColorExpandFillN'34'
Disables accelerated rectangular expansion blits from source patterns
stored in system memory (using a memory-mapped aperture).
Option N'34'XaaNoColor8x8PatternFillRectN'34'
Disables accelerated fills of a rectangular region with a full-color
pattern.
Option N'34'XaaNoColor8x8PatternFillTrapN'34'
Disables accelerated fills of a trapezoidal region with a full-color
pattern.
Option N'34'XaaNoDashedBresenhamLineN'34'
Disables accelerated dashed Bresenham line draws.
Option N'34'XaaNoDashedTwoPointLineN'34'
Disables accelerated dashed line draws between two arbitrary points.
Option N'34'XaaNoImageWriteRectN'34'
Disables accelerated transfers of full-color rectangular patterns from
system memory to video memory (using a memory-mapped aperture).
Option N'34'XaaNoMono8x8PatternFillRectN'34'
Disables accelerated fills of a rectangular region with a monochrome
pattern.
Option N'34'XaaNoMono8x8PatternFillTrapN'34'
Disables accelerated fills of a trapezoidal region with a monochrome
pattern.
Option N'34'XaaNoOffscreenPixmapsN'34'
Disables accelerated draws into pixmaps stored in offscreen video memory.
Option N'34'XaaNoPixmapCacheN'34'
Disables caching of patterns in offscreen video memory.
Disables accelerated rectangular expansion blits from source patterns
stored in offscreen video memory.
Option N'34'XaaNoScreenToScreenCopyN'34'
Disables accelerated copies of rectangular regions from one part of
video memory to another part of video memory.
Option N'34'XaaNoSolidBresenhamLineN'34'
Disables accelerated solid Bresenham line draws.
Option N'34'XaaNoSolidFillRectN'34'
Disables accelerated solid-color fills of rectangles.
Option N'34'XaaNoSolidFillTrapN'34'
Disables accelerated solid-color fills of Bresenham trapezoids.
Option N'34'XaaNoSolidHorVertLineN'34'
Disables accelerated solid horizontal and vertical line draws.
Option N'34'XaaNoSolidTwoPointLineN'34'
Disables accelerated solid line draws between two arbitrary points.
Each
Screen
section may optionally contain one or more
Display
subsections.
Those subsections provide depth/fbbpp specific configuration information,
and the one chosen depends on the depth and/or fbbpp that is being used for
the screen.
The
Display
subsection format is described in the section below.
DISPLAY SUBSECTION
Each
Screen
section may have multiple
Display
subsections.
The lqactiverq
Display
subsection is the first that matches the depth and/or fbbpp values being
used, or failing that, the first that has neither a depth or fbbpp value
specified.
The
Display
subsections are optional.
When there isn't one that matches the depth and/or fbbpp values being used,
all the parameters that can be specified here fall back to their defaults.
This entry specifies what colour depth the
Display
subsection is to be used for.
This entry is usually specified, but it may be omitted to create a match-all
Display
subsection or when wishing to match only against the
FbBpp
parameter.
The range of
depth
values that are allowed depends on the driver.
Most drivers support 8, 15, 16 and 24.
Some also support 1 and/or 4, and some may support other values (like 30).
Note:
depth
means the number of bits in a pixel that are actually used to determine
the pixel colour.
32 is not a valid
depth
value.
Most hardware that uses 32 bits per pixel only uses 24 of them to hold the
colour information, which means that the colour depth is 24, not 32.
FbBpp bpp
This entry specifies the framebuffer format this
Display
subsection is to be used for.
This entry is only needed when providing depth 24 configurations that allow
a choice between a 24 bpp packed framebuffer format and a 32bpp sparse
framebuffer format.
In most cases this entry should not be used.
Weight red-weight green-weight blue-weight
This optional entry specifies the relative RGB weighting to be used
for a screen is being used at depth 16 for drivers that allow multiple
formats.
This may also be specified from the command line with the
-weight
option (see
Xorg(1)).
Virtual xdim ydim
This optional entry specifies the virtual screen resolution to be used.
xdim
must be a multiple of either 8 or 16 for most drivers, and a multiple
of 32 when running in monochrome mode.
The given value will be rounded down if this is not the case.
Video modes which are too large for the specified virtual size will be
rejected.
If this entry is not present, the virtual screen resolution will be set to
accommodate all the valid video modes given in the
Modes
entry.
Some drivers/hardware combinations do not support virtual screens.
Refer to the appropriate driver-specific documentation for details.
ViewPort x0 y0
This optional entry sets the upper left corner of the initial display.
This is only relevant when the virtual screen resolution is different
from the resolution of the initial video mode.
If this entry is not given, then the initial display will be centered in
the virtual display area.
Modes N'34'mode-nameN'34' ...
This optional entry specifies the list of video modes to use.
Each
mode-name
specified must be in double quotes.
They must correspond to those specified or referenced in the appropriate
Monitor
section (including implicitly referenced built-in VESA standard modes).
The server will delete modes from this list which don't satisfy various
requirements.
The first valid mode in this list will be the default display mode for
startup.
The list of valid modes is converted internally into a circular list.
It is possible to switch to the next mode with
Ctrl+Alt+Keypad-Plus
and to the previous mode with
Ctrl+Alt+Keypad-Minus.
When this entry is omitted, the valid modes referenced by the appropriate
Monitor
section will be used. If the
Monitor
section contains no modes, then the selection will be taken from the
built-in VESA standard modes.
Visual N'34'visual-nameN'34'
This optional entry sets the default root visual type.
This may also be specified from the command line (see the
Xserver(1)
man page).
The visual types available for depth 8 are (default is
PseudoColor):
The visual type available for the depths 15, 16 and 24 are (default is
TrueColor):
TrueColorDirectColor
Not all drivers support
DirectColor
at these depths.
The visual types available for the depth 4 are (default is
StaticColor):
StaticGrayGrayScaleStaticColorPseudoColor
The visual type available for the depth 1 (monochrome) is
StaticGray.
Black red green blue
This optional entry allows the lqblackrq colour to be specified.
This is only supported at depth 1.
The default is black.
White red green blue
This optional entry allows the lqwhiterq colour to be specified.
This is only supported at depth 1.
The default is white.
Options
Option flags may be specified in the
Display
subsections.
These may include driver-specific options and driver-independent options.
The former are described in the driver-specific documentation.
Some of the latter are described above in the section about the
Screen
section, and they may also be included here.
SERVERLAYOUT SECTION
The config file may have multiple
ServerLayout
sections.
A lqserver layoutrq represents the binding of one or more screens
(Screen
sections) and one or more input devices
(InputDevice
sections) to form a complete configuration.
In multi-head configurations, it also specifies the relative layout of the
heads.
A
ServerLayout
section is considered lqactiverq if it is referenced by the
-layout
command line option or by an
Option N'34'DefaultServerLayoutN'34'
entry in the
ServerFlags
section (the former takes precedence over the latter).
If those options are not used, the first
ServerLayout
section found in the config file is considered the active one.
If no
ServerLayout
sections are present, the single active screen and two active (core)
input devices are selected as described in the relevant sections above.
Each
ServerLayout
section must have an
Identifier
entry and at least one
Screen
entry.
The
Identifier
entry specifies the unique name for this server layout.
The
ServerLayout
section provides information specific to the whole session, including
session-specific
Options.
The
ServerFlags
options (described above) may be specified here, and ones given here
override those given in the
ServerFlags
section.
The entries that may be used in this section are described here.
One of these entries must be given for each screen being used in
a session.
The
screen-id
field is mandatory, and specifies the
Screen
section being referenced.
The
screen-num
field is optional, and may be used to specify the screen number
in multi-head configurations.
When this field is omitted, the screens will be numbered in the order that
they are listed in.
The numbering starts from 0, and must be consecutive.
The
position-information
field describes the way multiple screens are positioned.
There are a number of different ways that this information can be provided:
x y
Absolute x y
These both specify that the upper left corner's coordinates are
(x,y).
The
Absolute
keyword is optional.
Some older versions of Xorg (4.2 and earlier) don't recognise the
Absolute
keyword, so it's safest to just specify the coordinates without it.
RightOf N'34'screen-idN'34'
LeftOf N'34'screen-idN'34'
Above N'34'screen-idN'34'
Below N'34'screen-idN'34'
Relative N'34'screen-idN'34' x y
These give the screen's location relative to another screen.
The first four position the screen immediately to the right, left, above or
below the other screen.
When positioning to the right or left, the top edges are aligned.
When positioning above or below, the left edges are aligned.
The
Relative
form specifies the offset of the screen's origin (upper left corner)
relative to the origin of another screen.
One of these entries should be given for each input device being used in
a session.
Normally at least two are required, one each for the core pointer and
keyboard devices.
If either of those is missing, suitable
InputDevice
entries are searched for using the method described above in the
INPUTDEVICE
section. The
idev-id
field is mandatory, and specifies the name of the
InputDevice
section being referenced.
Multiple
option
fields may be specified, each in double quotes.
The options permitted here are any that may also be given in the
InputDevice
sections.
Normally only session-specific input device options would be used here.
The most commonly used options are:
and the first two should normally be used to indicate the core pointer
and core keyboard devices respectively.
Options
In addition to the following, any option permitted in the
ServerFlags
section may also be specified here.
When the same option appears in both places, the value given here overrides
the one given in the
ServerFlags
section.
Option N'34'IsolateDeviceN'34' N'34'bus-idN'34'
Restrict device resets to the specified
bus-id.
See the
BusID
option (described in
DEVICE SECTION,
above) for the format of the
bus-id
parameter.
This option overrides
SingleCard,
if specified.
At present, only PCI devices can be isolated in this manner.
Option N'34'SingleCardN'34' N'34'booleanN'34'
As
IsolateDevice,
except that the bus ID of the first device in the layout is used.
Here is an example of a
ServerLayout
section for a dual headed configuration with two mice:
This optional section is used to provide some information for the
Direct Rendering Infrastructure.
Details about the format of this section
can be found in the README.DRI document, which is also available on-line at
<http://dri.freedesktop.org/>.
VENDOR SECTION
The optional
Vendor
section may be used to provide vendor-specific configuration information.
Multiple
Vendor
sections may be present, and they may contain an
Identifier
entry and multiple
Option
flags.
The data therein is not used in this release.
