linux/Documentation/fb/matroxfb.txt
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   1[This file is cloned from VesaFB. Thanks go to Gerd Knorr]
   2
   3What is matroxfb?
   4=================
   5
   6This is a driver for a graphic framebuffer for Matrox devices on
   7Alpha, Intel and PPC boxes.
   8
   9Advantages:
  10
  11 * It provides a nice large console (128 cols + 48 lines with 1024x768)
  12   without using tiny, unreadable fonts.
  13 * You can run XF{68,86}_FBDev or XFree86 fbdev driver on top of /dev/fb0
  14 * Most important: boot logo :-)
  15
  16Disadvantages:
  17
  18 * graphic mode is slower than text mode... but you should not notice
  19   if you use same resolution as you used in textmode.
  20
  21
  22How to use it?
  23==============
  24
  25Switching modes is done using the video=matroxfb:vesa:... boot parameter
  26or using `fbset' program.
  27
  28If you want, for example, enable a resolution of 1280x1024x24bpp you should
  29pass to the kernel this command line: "video=matroxfb:vesa:0x1BB".
  30
  31You should compile in both vgacon (to boot if you remove you Matrox from
  32box) and matroxfb (for graphics mode). You should not compile-in vesafb
  33unless you have primary display on non-Matrox VBE2.0 device (see 
  34Documentation/fb/vesafb.txt for details).
  35
  36Currently supported video modes are (through vesa:... interface, PowerMac
  37has [as addon] compatibility code):
  38
  39
  40[Graphic modes]
  41
  42bpp | 640x400  640x480  768x576  800x600  960x720
  43----+--------------------------------------------
  44  4 |            0x12             0x102            
  45  8 |  0x100    0x101    0x180    0x103    0x188   
  46 15 |           0x110    0x181    0x113    0x189   
  47 16 |           0x111    0x182    0x114    0x18A   
  48 24 |           0x1B2    0x184    0x1B5    0x18C   
  49 32 |           0x112    0x183    0x115    0x18B   
  50
  51
  52[Graphic modes (continued)]
  53
  54bpp | 1024x768 1152x864 1280x1024 1408x1056 1600x1200
  55----+------------------------------------------------
  56  4 |   0x104             0x106
  57  8 |   0x105    0x190    0x107     0x198     0x11C
  58 15 |   0x116    0x191    0x119     0x199     0x11D
  59 16 |   0x117    0x192    0x11A     0x19A     0x11E
  60 24 |   0x1B8    0x194    0x1BB     0x19C     0x1BF
  61 32 |   0x118    0x193    0x11B     0x19B
  62
  63
  64[Text modes]
  65
  66text | 640x400  640x480  1056x344  1056x400  1056x480
  67-----+------------------------------------------------
  68 8x8 |  0x1C0    0x108     0x10A     0x10B     0x10C
  698x16 | 2, 3, 7                       0x109
  70
  71You can enter these number either hexadecimal (leading `0x') or decimal
  72(0x100 = 256). You can also use value + 512 to achieve compatibility
  73with your old number passed to vesafb.
  74
  75Non-listed number can be achieved by more complicated command-line, for
  76example 1600x1200x32bpp can be specified by `video=matroxfb:vesa:0x11C,depth:32'.
  77
  78
  79X11
  80===
  81
  82XF{68,86}_FBDev should work just fine, but it is non-accelerated. On non-intel
  83architectures there are some glitches for 24bpp videomodes. 8, 16 and 32bpp
  84works fine.
  85
  86Running another (accelerated) X-Server like XF86_SVGA works too. But (at least)
  87XFree servers have big troubles in multihead configurations (even on first
  88head, not even talking about second). Running XFree86 4.x accelerated mga 
  89driver is possible, but you must not enable DRI - if you do, resolution and
  90color depth of your X desktop must match resolution and color depths of your
  91virtual consoles, otherwise X will corrupt accelerator settings.
  92
  93
  94SVGALib
  95=======
  96
  97Driver contains SVGALib compatibility code. It is turned on by choosing textual
  98mode for console. You can do it at boot time by using videomode
  992,3,7,0x108-0x10C or 0x1C0. At runtime, `fbset -depth 0' does this work.
 100Unfortunately, after SVGALib application exits, screen contents is corrupted.
 101Switching to another console and back fixes it. I hope that it is SVGALib's
 102problem and not mine, but I'm not sure.
 103
 104
 105Configuration
 106=============
 107
 108You can pass kernel command line options to matroxfb with
 109`video=matroxfb:option1,option2:value2,option3' (multiple options should be 
 110separated by comma, values are separated from options by `:'). 
 111Accepted options:
 112
 113mem:X    - size of memory (X can be in megabytes, kilobytes or bytes)
 114           You can only decrease value determined by driver because of
 115           it always probe for memory. Default is to use whole detected
 116           memory usable for on-screen display (i.e. max. 8 MB).
 117disabled - do not load driver; you can use also `off', but `disabled'
 118           is here too.
 119enabled  - load driver, if you have `video=matroxfb:disabled' in LILO
 120           configuration, you can override it by this (you cannot override
 121           `off'). It is default.
 122noaccel  - do not use acceleration engine. It does not work on Alphas.
 123accel    - use acceleration engine. It is default.
 124nopan    - create initial consoles with vyres = yres, thus disabling virtual
 125           scrolling.
 126pan      - create initial consoles as tall as possible (vyres = memory/vxres).
 127           It is default.
 128nopciretry - disable PCI retries. It is needed for some broken chipsets,
 129           it is autodetected for intel's 82437. In this case device does
 130           not comply to PCI 2.1 specs (it will not guarantee that every
 131           transaction terminate with success or retry in 32 PCLK).
 132pciretry - enable PCI retries. It is default, except for intel's 82437.
 133novga    - disables VGA I/O ports. It is default if BIOS did not enable device.
 134           You should not use this option, some boards then do not restart
 135           without power off.
 136vga      - preserve state of VGA I/O ports. It is default. Driver does not
 137           enable VGA I/O if BIOS did not it (it is not safe to enable it in
 138           most cases).
 139nobios   - disables BIOS ROM. It is default if BIOS did not enable BIOS itself.
 140           You should not use this option, some boards then do not restart
 141           without power off.
 142bios     - preserve state of BIOS ROM. It is default. Driver does not enable
 143           BIOS if BIOS was not enabled before.
 144noinit   - tells driver, that devices were already initialized. You should use
 145           it if you have G100 and/or if driver cannot detect memory, you see
 146           strange pattern on screen and so on. Devices not enabled by BIOS
 147           are still initialized. It is default.
 148init     - driver initializes every device it knows about.
 149memtype  - specifies memory type, implies 'init'. This is valid only for G200 
 150           and G400 and has following meaning:
 151             G200: 0 -> 2x128Kx32 chips, 2MB onboard, probably sgram
 152                   1 -> 2x128Kx32 chips, 4MB onboard, probably sgram
 153                   2 -> 2x256Kx32 chips, 4MB onboard, probably sgram
 154                   3 -> 2x256Kx32 chips, 8MB onboard, probably sgram
 155                   4 -> 2x512Kx16 chips, 8/16MB onboard, probably sdram only
 156                   5 -> same as above
 157                   6 -> 4x128Kx32 chips, 4MB onboard, probably sgram
 158                   7 -> 4x128Kx32 chips, 8MB onboard, probably sgram
 159             G400: 0 -> 2x512Kx16 SDRAM, 16/32MB
 160                        2x512Kx32 SGRAM, 16/32MB
 161                   1 -> 2x256Kx32 SGRAM, 8/16MB
 162                   2 -> 4x128Kx32 SGRAM, 8/16MB
 163                   3 -> 4x512Kx32 SDRAM, 32MB
 164                   4 -> 4x256Kx32 SGRAM, 16/32MB
 165                   5 -> 2x1Mx32 SDRAM, 32MB
 166                   6 -> reserved
 167                   7 -> reserved
 168           You should use sdram or sgram parameter in addition to memtype 
 169           parameter.
 170nomtrr   - disables write combining on frame buffer. This slows down driver but
 171           there is reported minor incompatibility between GUS DMA and XFree
 172           under high loads if write combining is enabled (sound dropouts).
 173mtrr     - enables write combining on frame buffer. It speeds up video accesses
 174           much. It is default. You must have MTRR support enabled in kernel
 175           and your CPU must have MTRR (f.e. Pentium II have them).
 176sgram    - tells to driver that you have Gxx0 with SGRAM memory. It has no
 177           effect without `init'.
 178sdram    - tells to driver that you have Gxx0 with SDRAM memory.
 179           It is a default.
 180inv24    - change timings parameters for 24bpp modes on Millennium and
 181           Millennium II. Specify this if you see strange color shadows around
 182           characters.
 183noinv24  - use standard timings. It is the default.
 184inverse  - invert colors on screen (for LCD displays)
 185noinverse - show true colors on screen. It is default.
 186dev:X    - bind driver to device X. Driver numbers device from 0 up to N,
 187           where device 0 is first `known' device found, 1 second and so on.
 188           lspci lists devices in this order.
 189           Default is `every' known device.
 190nohwcursor - disables hardware cursor (use software cursor instead).
 191hwcursor - enables hardware cursor. It is default. If you are using
 192           non-accelerated mode (`noaccel' or `fbset -accel false'), software
 193           cursor is used (except for text mode).
 194noblink  - disables cursor blinking. Cursor in text mode always blinks (hw
 195           limitation).
 196blink    - enables cursor blinking. It is default.
 197nofastfont - disables fastfont feature. It is default.
 198fastfont:X - enables fastfont feature. X specifies size of memory reserved for
 199             font data, it must be >= (fontwidth*fontheight*chars_in_font)/8.
 200             It is faster on Gx00 series, but slower on older cards.
 201grayscale - enable grayscale summing. It works in PSEUDOCOLOR modes (text,
 202            4bpp, 8bpp). In DIRECTCOLOR modes it is limited to characters
 203            displayed through putc/putcs. Direct accesses to framebuffer
 204            can paint colors.
 205nograyscale - disable grayscale summing. It is default.
 206cross4MB - enables that pixel line can cross 4MB boundary. It is default for
 207           non-Millennium.
 208nocross4MB - pixel line must not cross 4MB boundary. It is default for
 209             Millennium I or II, because of these devices have hardware
 210             limitations which do not allow this. But this option is
 211             incompatible with some (if not all yet released) versions of
 212             XF86_FBDev.
 213dfp      - enables digital flat panel interface. This option is incompatible with
 214           secondary (TV) output - if DFP is active, TV output must be
 215           inactive and vice versa. DFP always uses same timing as primary
 216           (monitor) output.
 217dfp:X    - use settings X for digital flat panel interface. X is number from
 218           0 to 0xFF, and meaning of each individual bit is described in
 219           G400 manual, in description of DAC register 0x1F. For normal operation
 220           you should set all bits to zero, except lowest bit. This lowest bit
 221           selects who is source of display clocks, whether G400, or panel.
 222           Default value is now read back from hardware - so you should specify
 223           this value only if you are also using `init' parameter.
 224outputs:XYZ - set mapping between CRTC and outputs. Each letter can have value
 225           of 0 (for no CRTC), 1 (CRTC1) or 2 (CRTC2), and first letter corresponds
 226           to primary analog output, second letter to the secondary analog output
 227           and third letter to the DVI output. Default setting is 100 for
 228           cards below G400 or G400 without DFP, 101 for G400 with DFP, and
 229           111 for G450 and G550. You can set mapping only on first card,
 230           use matroxset for setting up other devices.
 231vesa:X   - selects startup videomode. X is number from 0 to 0x1FF, see table
 232           above for detailed explanation. Default is 640x480x8bpp if driver
 233           has 8bpp support. Otherwise first available of 640x350x4bpp,
 234           640x480x15bpp, 640x480x24bpp, 640x480x32bpp or 80x25 text
 235           (80x25 text is always available).
 236
 237If you are not satisfied with videomode selected by `vesa' option, you
 238can modify it with these options:
 239
 240xres:X   - horizontal resolution, in pixels. Default is derived from `vesa'
 241           option.
 242yres:X   - vertical resolution, in pixel lines. Default is derived from `vesa'
 243           option.
 244upper:X  - top boundary: lines between end of VSYNC pulse and start of first
 245           pixel line of picture. Default is derived from `vesa' option.
 246lower:X  - bottom boundary: lines between end of picture and start of VSYNC
 247           pulse. Default is derived from `vesa' option.
 248vslen:X  - length of VSYNC pulse, in lines. Default is derived from `vesa'
 249           option.
 250left:X   - left boundary: pixels between end of HSYNC pulse and first pixel.
 251           Default is derived from `vesa' option.
 252right:X  - right boundary: pixels between end of picture and start of HSYNC
 253           pulse. Default is derived from `vesa' option.
 254hslen:X  - length of HSYNC pulse, in pixels. Default is derived from `vesa'
 255           option.
 256pixclock:X - dotclocks, in ps (picoseconds). Default is derived from `vesa'
 257             option and from `fh' and `fv' options.
 258sync:X   - sync. pulse - bit 0 inverts HSYNC polarity, bit 1 VSYNC polarity.
 259           If bit 3 (value 0x08) is set, composite sync instead of HSYNC is
 260           generated. If bit 5 (value 0x20) is set, sync on green is turned on.
 261           Do not forget that if you want sync on green, you also probably
 262           want composite sync.
 263           Default depends on `vesa'.
 264depth:X  - Bits per pixel: 0=text, 4,8,15,16,24 or 32. Default depends on
 265           `vesa'.
 266
 267If you know capabilities of your monitor, you can specify some (or all) of
 268`maxclk', `fh' and `fv'. In this case, `pixclock' is computed so that
 269pixclock <= maxclk, real_fh <= fh and real_fv <= fv.
 270
 271maxclk:X - maximum dotclock. X can be specified in MHz, kHz or Hz. Default is
 272           `don't care'.
 273fh:X     - maximum horizontal synchronization frequency. X can be specified
 274           in kHz or Hz. Default is `don't care'.
 275fv:X     - maximum vertical frequency. X must be specified in Hz. Default is
 276           70 for modes derived from `vesa' with yres <= 400, 60Hz for
 277           yres > 400.
 278
 279
 280Limitations
 281===========
 282
 283There are known and unknown bugs, features and misfeatures.
 284Currently there are following known bugs:
 285 + SVGALib does not restore screen on exit
 286 + generic fbcon-cfbX procedures do not work on Alphas. Due to this,
 287   `noaccel' (and cfb4 accel) driver does not work on Alpha. So everyone
 288   with access to /dev/fb* on Alpha can hang machine (you should restrict
 289   access to /dev/fb* - everyone with access to this device can destroy
 290   your monitor, believe me...).
 291 + 24bpp does not support correctly XF-FBDev on big-endian architectures.
 292 + interlaced text mode is not supported; it looks like hardware limitation,
 293   but I'm not sure.
 294 + Gxx0 SGRAM/SDRAM is not autodetected.
 295 + If you are using more than one framebuffer device, you must boot kernel
 296   with 'video=scrollback:0'.
 297 + maybe more...
 298And following misfeatures:
 299 + SVGALib does not restore screen on exit.
 300 + pixclock for text modes is limited by hardware to
 301    83 MHz on G200
 302    66 MHz on Millennium I
 303    60 MHz on Millennium II
 304   Because I have no access to other devices, I do not know specific
 305   frequencies for them. So driver does not check this and allows you to
 306   set frequency higher that this. It causes sparks, black holes and other
 307   pretty effects on screen. Device was not destroyed during tests. :-)
 308 + my Millennium G200 oscillator has frequency range from 35 MHz to 380 MHz
 309   (and it works with 8bpp on about 320 MHz dotclocks (and changed mclk)).
 310   But Matrox says on product sheet that VCO limit is 50-250 MHz, so I believe
 311   them (maybe that chip overheats, but it has a very big cooler (G100 has
 312   none), so it should work).
 313 + special mixed video/graphics videomodes of Mystique and Gx00 - 2G8V16 and
 314   G16V16 are not supported
 315 + color keying is not supported
 316 + feature connector of Mystique and Gx00 is set to VGA mode (it is disabled
 317   by BIOS)
 318 + DDC (monitor detection) is supported through dualhead driver
 319 + some check for input values are not so strict how it should be (you can
 320   specify vslen=4000 and so on).
 321 + maybe more...
 322And following features:
 323 + 4bpp is available only on Millennium I and Millennium II. It is hardware
 324   limitation.
 325 + selection between 1:5:5:5 and 5:6:5 16bpp videomode is done by -rgba 
 326   option of fbset: "fbset -depth 16 -rgba 5,5,5" selects 1:5:5:5, anything
 327   else selects 5:6:5 mode.
 328 + text mode uses 6 bit VGA palette instead of 8 bit (one of 262144 colors
 329   instead of one of 16M colors). It is due to hardware limitation of 
 330   Millennium I/II and SVGALib compatibility.
 331
 332
 333Benchmarks
 334==========
 335It is time to redraw whole screen 1000 times in 1024x768, 60Hz. It is
 336time for draw 6144000 characters on screen through /dev/vcsa
 337(for 32bpp it is about 3GB of data (exactly 3000 MB); for 8x16 font in 
 33816 seconds, i.e. 187 MBps).
 339Times were obtained from one older version of driver, now they are about 3%
 340faster, it is kernel-space only time on P-II/350 MHz, Millennium I in 33 MHz
 341PCI slot, G200 in AGP 2x slot. I did not test vgacon.
 342
 343NOACCEL
 344        8x16                 12x22
 345        Millennium I  G200   Millennium I  G200
 3468bpp    16.42         9.54   12.33         9.13
 34716bpp   21.00        15.70   19.11        15.02
 34824bpp   36.66        36.66   35.00        35.00
 34932bpp   35.00        30.00   33.85        28.66
 350
 351ACCEL, nofastfont
 352        8x16                 12x22                6x11
 353        Millennium I  G200   Millennium I  G200   Millennium I  G200
 3548bpp     7.79         7.24   13.55         7.78   30.00        21.01
 35516bpp    9.13         7.78   16.16         7.78   30.00        21.01
 35624bpp   14.17        10.72   18.69        10.24   34.99        21.01
 35732bpp   16.15        16.16   18.73        13.09   34.99        21.01
 358
 359ACCEL, fastfont
 360        8x16                 12x22                6x11
 361        Millennium I  G200   Millennium I  G200   Millennium I  G200
 3628bpp     8.41         6.01    6.54         4.37   16.00        10.51
 36316bpp    9.54         9.12    8.76         6.17   17.52        14.01
 36424bpp   15.00        12.36   11.67        10.00   22.01        18.32
 36532bpp   16.18        18.29*  12.71        12.74   24.44        21.00
 366
 367TEXT
 368        8x16
 369        Millennium I  G200
 370TEXT     3.29         1.50
 371
 372* Yes, it is slower than Millennium I.
 373
 374
 375Dualhead G400
 376=============
 377Driver supports dualhead G400 with some limitations:
 378 + secondary head shares videomemory with primary head. It is not problem
 379   if you have 32MB of videoram, but if you have only 16MB, you may have
 380   to think twice before choosing videomode (for example twice 1880x1440x32bpp
 381   is not possible).
 382 + due to hardware limitation, secondary head can use only 16 and 32bpp
 383   videomodes.
 384 + secondary head is not accelerated. There were bad problems with accelerated
 385   XFree when secondary head used to use acceleration.
 386 + secondary head always powerups in 640x480@60-32 videomode. You have to use
 387   fbset to change this mode.
 388 + secondary head always powerups in monitor mode. You have to use fbmatroxset
 389   to change it to TV mode. Also, you must select at least 525 lines for
 390   NTSC output and 625 lines for PAL output.
 391 + kernel is not fully multihead ready. So some things are impossible to do.
 392 + if you compiled it as module, you must insert i2c-matroxfb, matroxfb_maven
 393   and matroxfb_crtc2 into kernel.
 394
 395
 396Dualhead G450
 397=============
 398Driver supports dualhead G450 with some limitations:
 399 + secondary head shares videomemory with primary head. It is not problem
 400   if you have 32MB of videoram, but if you have only 16MB, you may have
 401   to think twice before choosing videomode.
 402 + due to hardware limitation, secondary head can use only 16 and 32bpp
 403   videomodes.
 404 + secondary head is not accelerated.
 405 + secondary head always powerups in 640x480@60-32 videomode. You have to use
 406   fbset to change this mode.
 407 + TV output is not supported
 408 + kernel is not fully multihead ready, so some things are impossible to do.
 409 + if you compiled it as module, you must insert matroxfb_g450 and matroxfb_crtc2
 410   into kernel.
 411        
 412--
 413Petr Vandrovec <vandrove@vc.cvut.cz>
 414
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