1OPENCHROME(4)              Kernel Interfaces Manual              OPENCHROME(4)
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NAME

6       openchrome - video driver for VIA Unichromes
7

SYNOPSIS

9       Section "Device"
10         Identifier "devname"
11         Driver "openchrome"
12         ...
13       EndSection
14
15

DESCRIPTION

17       openchrome  is  an Xorg driver for VIA chipsets that have an integrated
18       Unichrome graphics engine.
19
20       The  openchrome  driver  supports  the  following   chipsets:   CLE266,
21       KM400/KN400/KM400A/P4M800,       CN400/PM800/PN800/PM880,       K8M800,
22       CN700/VM800/P4M800Pro,  CX700,  P4M890,   K8M890,   P4M900/VN896/CN896,
23       VX800,  VX855  and  VX900.   The driver includes 2D acceleration and Xv
24       video overlay extensions.  Flat panel, TV, and  VGA  outputs  are  sup‐
25       ported, depending on the hardware configuration.
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27       3D  direct  rendering is available using experimental drivers from Mesa
28       (www.mesa3d.org).  There is also an XvMC client  library  for  hardware
29       acceleration  of  MPEG1/MPEG2  decoding  (not available on the KM/N400)
30       that uses the Direct Rendering Infrastructure (DRI).  The  XvMC  client
31       library implements a non-standard "VLD" extension to the XvMC standard.
32       The current Direct Rendering Manager (DRM) kernel module  is  available
33       at dri.sourceforge.net.
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35       The  driver  supports  free  modes  for  Unichrome Pros (K8M800/K8N800,
36       PM800/PN800, and CN400).  For plain Unichromes  (CLE266,  KM400/KN400),
37       it currently supports only a limited number of dotclocks, so if you are
38       using X modelines you must make sure that the dotclock is one of  those
39       supported.   Supported  dotclocks on plain Unichromes are currently (in
40       MHz): 25.2, 25.312, 26.591, 31.5, 31.704, 32.663, 33.750,  35.5,  36.0,
41       39.822,  40.0,  41.164, 46.981, 49.5, 50.0, 56.3, 57.284, 64.995, 65.0,
42       65.028,  74.480,  75.0,  78.8,  81.613,  94.5,  108.0,  108.28,  122.0,
43       122.726,  135.0,  148.5,  155.8,  157.5,  161.793, 162.0, 175.5, 189.0,
44       202.5, 204.8, 218.3, 229.5.  On top  of  this,  bandwidth  restrictions
45       apply for both Unichromes and Unichrome Pros.
46

CONFIGURATION DETAILS

48       Please  refer  to xorg.conf(5) for general configuration details.  This
49       section only covers configuration details specific to this driver.
50
51       The following driver options are supported:
52
53       Option "AccelMethod"  "string"
54              The driver supports "XAA" and "EXA" acceleration  methods.   The
55              default  method  is  XAA, since EXA is still experimental.  Con‐
56              trary to XAA, EXA implements acceleration for screen uploads and
57              downloads  (if  DRI  is  enabled)  and  for the Render/Composite
58              extension.
59
60       Option "ActiveDevice"  "string"
61              Specifies the active device combination.  Any string  containing
62              "CRT",  "LCD",  "DFP", "TV" should be possible. "CRT" represents
63              anything that is connected to the VGA port, "LCD" is for  laptop
64              panels  (not TFT screens attached to the VGA port), "DFP" is for
65              screens connected to the DVI  port,  "TV"  is  self-explanatory.
66              The default is to use what is detected.  The driver is currently
67              unable to use LCD and TV simultaneously,  and  will  favour  the
68              LCD.   The  DVI  port  is  not  properly  probed and needs to be
69              enabled with this option.
70
71       Option "AGPMem"  "integer"
72              Sets the amount of AGP memory that  is  allocated  at  X  server
73              startup.   The  allocated memory will be "integer" kB.  This AGP
74              memory is used  for  the  AGP  command  buffer  (if  the  option
75              "EnableAGPDMA"  is set to "true"), for DRI textures, and for the
76              EXA scratch area.  The driver will allocate at least one  system
77              page  of  AGP memory, or -- if the AGP command buffer is used --
78              at least 2 MB plus one system page.  If there is no room for the
79              EXA  scratch  area in AGP space, it will be allocated from VRAM.
80              If there is no room for DRI textures,  they  will  be  allocated
81              from  the  DRI  part  of VRAM (see the option "MaxDRIMem").  The
82              default amount of AGP is 32768 kB.  Note that the  AGP  aperture
83              set  in  the  BIOS must be able to accommodate the amount of AGP
84              memory specified here.  Otherwise no AGP memory will  be  avail‐
85              able.  It is safe to set a very large AGP aperture in the BIOS.
86
87       Option "Center"  "boolean"
88              Enables  image  centering  on DVI displays.  The default is dis‐
89              abled.
90
91       Option "DisableIRQ"  "boolean"
92              Disables the vertical blank IRQ.  This is a workaround for  some
93              mainboards   that  have  problems  with  IRQs  coming  from  the
94              Unichrome engine.  With IRQs disabled, DRI clients have  no  way
95              to  synchronize  their  drawing  to Vblank.  (IRQ is disabled by
96              default on the KM400 and K8M800 chipsets.)
97
98       Option "DisableVQ"  "boolean"
99              Disables the use of the virtual command  queue.   The  queue  is
100              enabled by default.
101
102       Option "EnableAGPDMA"  "boolean"
103              Enables  the  AGP  DMA functionality in DRM.  This requires that
104              DRI is enabled and will force 2D and 3D acceleration to use  AGP
105              DMA.   The  XvMC  DRI  client  will also make use of this on the
106              CLE266 to consume much less CPU.  (This  option  is  enabled  by
107              default, except on the K8M890 and P4M900.)
108
109       Option "ExaNoComposite"  "boolean"
110              If  EXA is enabled (using the option "AccelMethod"), this option
111              enables acceleration of compositing.  Since EXA, and in particu‐
112              lar its composite acceleration, is still experimental, this is a
113              way to disable a misbehaving composite acceleration.
114
115       Option "ExaScratchSize"  "integer"
116              Sets the size of the EXA scratch area  to  "integer"  kB.   This
117              area  is used by EXA as a last place to look for available space
118              for pixmaps.  Too little space will slow compositing down.  This
119              option should be set to the size of the largest pixmap used.  If
120              you have a screen width of over 1024 pixels and use 24 bpp,  set
121              this to 8192.  Otherwise you can leave this at the default 4096.
122              The space will be allocated from AGP memory if available, other‐
123              wise from VRAM.
124
125       Option "LCDDualEdge"  "boolean"
126              Enables  the  use of dual-edge mode to set the LCD.  The default
127              is disabled.
128
129       Option "MaxDRIMem"  "integer"
130              Sets the maximum amount of VRAM memory allocated for DRI clients
131              to  "integer"  kB.  Normally DRI clients  get half the available
132              VRAM size, but in some cases it may make  sense  to  limit  this
133              amount.   For  example, if you are using a composite manager and
134              you want to give as much memory as possible to  the  EXA  pixmap
135              storage area.
136
137       Option "MigrationHeuristic"  "string"
138              Sets  the  heuristic  for  EXA pixmap migration.  This is an EXA
139              core option, and starting from Xorg server  version  1.3.0  this
140              defaults  to "always".  The openchrome driver performs best with
141              "greedy", so you should really add this option to your  configu‐
142              ration file.  The third possibility is "smart".
143
144       Option "NoAccel"  "boolean"
145              Disables  the  use  of  hardware  acceleration.  Acceleration is
146              enabled by default.
147
148       Option "NoAGPFor2D"  "boolean"
149              Disables the use of AGP DMA for 2D acceleration, even  when  AGP
150              DMA is enabled.  The default is enabled.
151
152       Option "NoXVDMA"  "boolean"
153              If  DRI  is  enabled, Xv normally uses PCI DMA to transfer video
154              images from system to frame-buffer  memory.   This  is  somewhat
155              slower than direct copies due to the limitations of the PCI bus,
156              but on the other hand it decreases CPU usage significantly, par‐
157              ticularly on computers with fast processors.  Some video players
158              are buggy and will display rendering artifacts when PCI  DMA  is
159              used.   If you experience this, or don't want your PCI bus to be
160              stressed with Xv images, set this option to "true".  This option
161              has no effect when DRI is not enabled.
162
163       Option "PanelSize"  "string"
164              Specifies the size (width x height) of the LCD panel attached to
165              the system.  The sizes 640x480,  800x600,  1024x768,  1280x1024,
166              and 1400x1050 are supported.
167
168       Option "RotationType"  "string"
169              Enabled  rotation  by using RandR. The driver only support unac‐
170              celerated  RandR   rotations   "SWRandR".   Hardware   rotations
171              "HWRandR" is currently unimplemented.
172
173       Option "Rotate"  "string"
174              Rotates  the  display  either clockwise ("CW"), counterclockwise
175              ("CCW") and upside-down ("UD"). Rotation is only supported unac‐
176              celerated.   Adding option "Rotate", enables RandR rotation fea‐
177              ture.  The RandR allows clients to dynamically change X screens.
178
179       Option "ShadowFB"  "boolean"
180              Enables the use of a shadow frame buffer.  This is required when
181              rotating the display, but otherwise defaults to disabled.
182
183       Option "SWCursor"  "boolean"
184              Enables  the use of a software cursor.  The default is disabled:
185              the hardware cursor is used.
186
187       Option "TVDeflicker"  "integer"
188              Specifies the deflicker setting for TV output.  Valid values are
189              "0",  "1",  and  "2".   Here 0 means no deflicker, 1 means 1:1:1
190              deflicker, and 2 means 1:2:1 deflicker.
191
192       Option "TVDotCrawl"  "boolean"
193              Enables dot-crawl suppression.  The default is disabled.
194
195       Option "TVOutput"  "string"
196              Specifies which TV output  to  use.   The  driver  supports  "S-
197              Video",  "Composite",  "SC",  "RGB",  and "YCbCr" outputs.  Note
198              that on some EPIA boards the composite-video port is shared with
199              audio-out and is selected via a jumper.
200
201       Option "TVPort"  "string"
202              Specifies  TV  port.   The  driver  currently  supports  "DVP0",
203              "DVP1", "DFPHigh" and "DFPLow" ports.
204
205       Option "TVType"  "string"
206              Specifies TV  output  format.   The  driver  currently  supports
207              "NTSC" and "PAL" timings only.
208
209       Option "VBEModes"  "boolean"
210              Enables  the use of VBE BIOS calls for setting the display mode.
211              This mimics the behaviour of the vesa driver but still  provides
212              acceleration  and  other  features.   This option may be used if
213              your hardware works with  the  vesa  driver  but  not  with  the
214              openchrome  driver.   It  may not work on 64-bit systems.  Using
215              "VBEModes" may speed up driver acceleration significantly due to
216              a more aggressive hardware setting, particularly on systems with
217              low memory bandwidth.  Your refresh rate may be limited to 60 Hz
218              on some systems.
219
220       Option "VBESaveRestore"  "boolean"
221              Enables  the  use of VBE BIOS calls for saving and restoring the
222              display state when the  X  server  is  launched.   This  can  be
223              extremely  slow  on  some hardware, and the system may appear to
224              have locked for 10 seconds or so.  The default  is  to  use  the
225              driver builtin function.  This option only works if option "VBE‐
226              Modes" is enabled.
227
228       Option "VideoRAM"  "integer"
229              Overrides the VideoRAM  autodetection.   This  should  never  be
230              needed.
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TV ENCODERS

233       Unichromes tend to be paired with several different TV encoders.
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235       VIA Technologies VT1621
236              Still  untested,  as no combination with a Unichrome is known or
237              available.  Supports the following normal modes:  "640x480"  and
238              "800x600".   Use  "640x480Over"  and  "800x600Over" for vertical
239              overscan.  These modes are made available by the  driver;  mode‐
240              lines provided in xorg.conf will be ignored.
241
242       VIA Technologies VT1622, VT1622A, VT1623
243              Supports  the following modes: "640x480", "800x600", "1024x768",
244              "848x480", "720x480" (NTSC only) and "720x576" (PAL only).   Use
245              "640x480Over",   "800x600Over",  "1024x768Over",  "848x480Over",
246              "720x480Over" (NTSC) and "720x576Over" (PAL) for vertical  over‐
247              scan.   The  modes  "720x480Noscale" (NTSC) and "720x576Noscale"
248              (PAL) (available on  VT1622  only)  provide  cleaner  TV  output
249              (unscaled  with  only  minimal  overscan).  These modes are made
250              available by the driver; modelines provided in xorg.conf will be
251              ignored.
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253

SEE ALSO

255       Xorg(1), xorg.conf(5), Xserver(1), X(7), EXA(5), Xv(5)
256

AUTHORS

258       Authors include: ...
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262X Version 11              xf86-video-openchrome 0.6.0            OPENCHROME(4)
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