Provided by:
xserver-xorg-video-unichrome_0.2.6.99-0ubuntu1_i386 
NAME
via - VIA Unichrome video driver
SYNOPSIS
Section "Device"
Identifier "devname"
Driver "via"
...
EndSection
DESCRIPTION
via is an Xorg driver for VIA Unichrome integrated graphics.
The via driver supports the following devices:
VT3122: CLE266 (CastleRock).
VT7205: KM400, KM400A, KN400, P4M800 (Unichrome).
VT3108: K8M800, K8N800, K8N800A (Unichrome Pro, aka Pro B).
VT3118: CN400, PM800, PM880, PN800 (Unichrome Pro A).
VT3344: VN800, P4M800Pro (Unichrome Pro).
VT3157: CX700 (Unichrome Pro - not yet released).
VT3130: K8M890 (Chrome9 IGP).
VT3343: P4M890 (Unichrome Pro - not yet released).
VT3118 through VT3343 support is currently non-existent, as the developer
has no direct access to this hardware yet.
This driver is being developed at http://unichrome.sourceforge.net/.
It is not endorsed or supported by VIA Technologies. For support, refer
to http://unichrome.sourceforge.net/ directly.
CONFIGURATION DETAILS
Please refer to xorg.conf(5) for general configuration details. This
section only covers configuration details specific to this driver.
The following driver options are supported
Option "ActiveDevice" "string"
Specify the active device combination. Any string containing
"CRT", "DFP" (for Digital Flat Panel), "TV" should be possible.
The default is to use everything that is detected. The driver is
currently unable to use DFP and TV simultaneously, and will
favour the DFP.
Option "NoAccel" "boolean"
Disable or enable acceleration. Default: acceleration is
enabled.
Option "HWCursor" "boolean"
Disable or enable use of hardware cursors. The default is
enabled.
Option "SWCursor" "boolean"
Disable or enable the use of a software cursor. The default is
disabled.
Option "ShadowFB" "boolean"
Use a shadow frame buffer. This is required when rotating the
display, but otherwise defaults to disabled.
Option "Rotate" "string"
Rotate the display either clockwise ("CW") or counter clockwise
("CCW"). Rotation is only supported unaccelerated.
Option "DisableVQ" "boolean"
Disable or enable the use of VQ. VQ is enabled by default.
Option "DRIXINERAMA" "boolean"
Set DRI Xinerama mode. Currently unsupported.
Option "DisableIRQ" "boolean"
Disables Vblank IRQ. A workaround for some mainboards that have
problems with IRQs from the unichrome chip. With IRQ disabled,
DRI clients have no way to sync drawing to Vblank.
Option "EnableAGPDMA" "boolean"
Enable the AGP DMA functionality in DRM. This requires that DRI
is enabled and will force 2D, and 3D acceleration to use AGP
DMA.
Option "NoAGPFor2D" "boolean"
With this option on, 2D acceleration will not use AGP DMA even
if it is enabled.
Option "UseDMACopy" "boolean"
Use the DRM DMA blit to copy the Xv buffer to framebuffer,
enabled per default.
CRT Specific Options
With CRT we mean every monitor that’s connected to the analog-out meant
for CRTs. This irrespective of whether this monitor is plat panel based
or not.
VT3122Cx (Rev 16 and up) and all other unichromes support CRT auto
detection. This seems to be missing or broken on VT3122Ax. This
integer value should be provided in kHz and should normally range
somewhere between 20000 and 300000.
Option "CRTBandWidth" "integer"
This specifies the maximum bandwidth a CRT allows and limits the
mode’s dotclock. This integer value should be provided in kHz
and should normally range somewhere between 20000 and 300000.
This information is usually provided as part of DDC/EDID data
and thus autodetected.
Panel Specific Options
Unichromes have a built-in panel scaler and allow for either LVDS
encoders or directly (aka TTL) connected panels (DFP).
For VT3122 and VT7205 the support is extremely limited, as the hardware
to fix this code is simply not available. You should be able to get
native resolution working on your CLE266 or KM400 based laptop though,
but don’t expect it to be smooth.
For VT3108, native resolution and centered modes are possible. Scaling
will be made possible when the secondary CRTC is properly implemented.
Option "PanelSize" "string"
Specify the size (width x height) of the LCD panel attached to
the system. Sizes 640x480, 800x600, 1024x768, 1280x1024, and
1400x1050 are supported. This shouldn’t be required as this
usually is a BIOS initialised value.
Supported TV Encoders
Unichromes tend to be paired with several different TV Encoders. The
presence of these TV encoders is detected. They are automatically
enabled when a TV is attached.
Chrontel CH7011
Supports the following modes: "640x480", "800x600", "1024x768". Use
"640x480Over", "800x600Over" and "1024x768Over" for vertical overscan.
These modes are made available by the driver and modelines provided in
xorg.conf will be ignored when the TV encoder is used.
Option "TVOutput" "string"
Specify which TV output to use. The driver supports "S-Video",
"Composite", "SC", "RGB" and "YCbCr" outputs. The default is to
use the cable type that is detected.
Option "TVStandard" "string"
Specify TV Standard. The CH7011 currently supports "NTSC" and
"PAL".
VIA Technologies VT1622, VT1622A, VT1623
Supports the following modes: "640x480", "800x600", "1024x768",
"848x480", "720x480" (NTSC only) and "720x576" (PAL only). Use
"640x480Over", "800x600Over", "1024x768Over", "848x480Over",
"720x480Over" (NTSC) and "720x576Over" (PAL) for vertical overscan.
The modes "720x480Noscale" (NTSC VT1622 only) and "720x576Noscale" (PAL
VT1622 and VT1622a only) provide cleaner TV output (unscaled with only
minimal overscan). These modes are made available by the driver and
modelines provided in xorg.conf will be ignored when the TV encoder is
used.
Option "TVDeflicker" "integer"
Specify deflicker setting for TV output. Valid values are 0,1,2
0) No deflicker, 1) 1:1:1 deflicker, 2) 1:2:1 deflicker.
Option "TVDotCrawl" "boolean"
Disable or enable dotcrawl. This is available for NTSC modes
only.
Option "TVOutput" "string"
Specify which TV output to use. The driver supports "S-Video",
"Composite", "SC", "RGB" and "YCbCr" outputs. The default is to
use the cable type that is detected.
Option "TVStandard" "string"
Specify TV Standard. The driver currently supports "NTSC" and
"PAL".
BUGS
Plenty. Feel free to file more at the http://unichrome.sf.net/ bug
tracker.
SEE ALSO
Xorg(1), xorg.conf(5), xorgconfig(1), Xserver(1), X(7)
AUTHORS
Authors include: Luc Verhaegen (libv@skynet.be)