414 lines
19 KiB
Plaintext
414 lines
19 KiB
Plaintext
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[This file is cloned from VesaFB. Thanks go to Gerd Knorr]
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What is matroxfb?
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=================
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This is a driver for a graphic framebuffer for Matrox devices on
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Alpha, Intel and PPC boxes.
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Advantages:
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* It provides a nice large console (128 cols + 48 lines with 1024x768)
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without using tiny, unreadable fonts.
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* You can run XF{68,86}_FBDev or XFree86 fbdev driver on top of /dev/fb0
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* Most important: boot logo :-)
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Disadvantages:
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* graphic mode is slower than text mode... but you should not notice
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if you use same resolution as you used in textmode.
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How to use it?
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==============
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Switching modes is done using the video=matroxfb:vesa:... boot parameter
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or using `fbset' program.
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If you want, for example, enable a resolution of 1280x1024x24bpp you should
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pass to the kernel this command line: "video=matroxfb:vesa:0x1BB".
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You should compile in both vgacon (to boot if you remove you Matrox from
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box) and matroxfb (for graphics mode). You should not compile-in vesafb
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unless you have primary display on non-Matrox VBE2.0 device (see
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Documentation/fb/vesafb.txt for details).
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Currently supported video modes are (through vesa:... interface, PowerMac
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has [as addon] compatibility code):
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[Graphic modes]
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bpp | 640x400 640x480 768x576 800x600 960x720
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----+--------------------------------------------
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4 | 0x12 0x102
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8 | 0x100 0x101 0x180 0x103 0x188
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15 | 0x110 0x181 0x113 0x189
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16 | 0x111 0x182 0x114 0x18A
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24 | 0x1B2 0x184 0x1B5 0x18C
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32 | 0x112 0x183 0x115 0x18B
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[Graphic modes (continued)]
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bpp | 1024x768 1152x864 1280x1024 1408x1056 1600x1200
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----+------------------------------------------------
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4 | 0x104 0x106
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8 | 0x105 0x190 0x107 0x198 0x11C
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15 | 0x116 0x191 0x119 0x199 0x11D
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16 | 0x117 0x192 0x11A 0x19A 0x11E
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24 | 0x1B8 0x194 0x1BB 0x19C 0x1BF
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32 | 0x118 0x193 0x11B 0x19B
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[Text modes]
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text | 640x400 640x480 1056x344 1056x400 1056x480
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-----+------------------------------------------------
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8x8 | 0x1C0 0x108 0x10A 0x10B 0x10C
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8x16 | 2, 3, 7 0x109
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You can enter these number either hexadecimal (leading `0x') or decimal
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(0x100 = 256). You can also use value + 512 to achieve compatibility
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with your old number passed to vesafb.
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Non-listed number can be achieved by more complicated command-line, for
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example 1600x1200x32bpp can be specified by `video=matroxfb:vesa:0x11C,depth:32'.
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X11
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===
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XF{68,86}_FBDev should work just fine, but it is non-accelerated. On non-intel
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architectures there are some glitches for 24bpp videomodes. 8, 16 and 32bpp
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works fine.
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Running another (accelerated) X-Server like XF86_SVGA works too. But (at least)
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XFree servers have big troubles in multihead configurations (even on first
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head, not even talking about second). Running XFree86 4.x accelerated mga
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driver is possible, but you must not enable DRI - if you do, resolution and
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color depth of your X desktop must match resolution and color depths of your
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virtual consoles, otherwise X will corrupt accelerator settings.
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SVGALib
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=======
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Driver contains SVGALib compatibility code. It is turned on by choosing textual
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mode for console. You can do it at boot time by using videomode
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2,3,7,0x108-0x10C or 0x1C0. At runtime, `fbset -depth 0' does this work.
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Unfortunately, after SVGALib application exits, screen contents is corrupted.
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Switching to another console and back fixes it. I hope that it is SVGALib's
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problem and not mine, but I'm not sure.
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Configuration
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=============
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You can pass kernel command line options to matroxfb with
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`video=matroxfb:option1,option2:value2,option3' (multiple options should be
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separated by comma, values are separated from options by `:').
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Accepted options:
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mem:X - size of memory (X can be in megabytes, kilobytes or bytes)
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You can only decrease value determined by driver because of
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it always probe for memory. Default is to use whole detected
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memory usable for on-screen display (i.e. max. 8 MB).
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disabled - do not load driver; you can use also `off', but `disabled'
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is here too.
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enabled - load driver, if you have `video=matroxfb:disabled' in LILO
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configuration, you can override it by this (you cannot override
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`off'). It is default.
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noaccel - do not use acceleration engine. It does not work on Alphas.
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accel - use acceleration engine. It is default.
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nopan - create initial consoles with vyres = yres, thus disabling virtual
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scrolling.
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pan - create initial consoles as tall as possible (vyres = memory/vxres).
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It is default.
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nopciretry - disable PCI retries. It is needed for some broken chipsets,
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it is autodetected for intel's 82437. In this case device does
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not comply to PCI 2.1 specs (it will not guarantee that every
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transaction terminate with success or retry in 32 PCLK).
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pciretry - enable PCI retries. It is default, except for intel's 82437.
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novga - disables VGA I/O ports. It is default if BIOS did not enable device.
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You should not use this option, some boards then do not restart
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without power off.
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vga - preserve state of VGA I/O ports. It is default. Driver does not
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enable VGA I/O if BIOS did not it (it is not safe to enable it in
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most cases).
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nobios - disables BIOS ROM. It is default if BIOS did not enable BIOS itself.
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You should not use this option, some boards then do not restart
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without power off.
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bios - preserve state of BIOS ROM. It is default. Driver does not enable
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BIOS if BIOS was not enabled before.
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noinit - tells driver, that devices were already initialized. You should use
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it if you have G100 and/or if driver cannot detect memory, you see
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strange pattern on screen and so on. Devices not enabled by BIOS
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are still initialized. It is default.
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init - driver initializes every device it knows about.
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memtype - specifies memory type, implies 'init'. This is valid only for G200
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and G400 and has following meaning:
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G200: 0 -> 2x128Kx32 chips, 2MB onboard, probably sgram
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1 -> 2x128Kx32 chips, 4MB onboard, probably sgram
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2 -> 2x256Kx32 chips, 4MB onboard, probably sgram
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3 -> 2x256Kx32 chips, 8MB onboard, probably sgram
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4 -> 2x512Kx16 chips, 8/16MB onboard, probably sdram only
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5 -> same as above
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6 -> 4x128Kx32 chips, 4MB onboard, probably sgram
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7 -> 4x128Kx32 chips, 8MB onboard, probably sgram
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G400: 0 -> 2x512Kx16 SDRAM, 16/32MB
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2x512Kx32 SGRAM, 16/32MB
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1 -> 2x256Kx32 SGRAM, 8/16MB
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2 -> 4x128Kx32 SGRAM, 8/16MB
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3 -> 4x512Kx32 SDRAM, 32MB
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4 -> 4x256Kx32 SGRAM, 16/32MB
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5 -> 2x1Mx32 SDRAM, 32MB
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6 -> reserved
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7 -> reserved
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You should use sdram or sgram parameter in addition to memtype
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parameter.
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nomtrr - disables write combining on frame buffer. This slows down driver but
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there is reported minor incompatibility between GUS DMA and XFree
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under high loads if write combining is enabled (sound dropouts).
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mtrr - enables write combining on frame buffer. It speeds up video accesses
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much. It is default. You must have MTRR support enabled in kernel
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and your CPU must have MTRR (f.e. Pentium II have them).
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sgram - tells to driver that you have Gxx0 with SGRAM memory. It has no
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effect without `init'.
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sdram - tells to driver that you have Gxx0 with SDRAM memory.
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It is a default.
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inv24 - change timings parameters for 24bpp modes on Millenium and
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Millenium II. Specify this if you see strange color shadows around
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characters.
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noinv24 - use standard timings. It is the default.
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inverse - invert colors on screen (for LCD displays)
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noinverse - show true colors on screen. It is default.
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dev:X - bind driver to device X. Driver numbers device from 0 up to N,
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where device 0 is first `known' device found, 1 second and so on.
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lspci lists devices in this order.
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Default is `every' known device.
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nohwcursor - disables hardware cursor (use software cursor instead).
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hwcursor - enables hardware cursor. It is default. If you are using
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non-accelerated mode (`noaccel' or `fbset -accel false'), software
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cursor is used (except for text mode).
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noblink - disables cursor blinking. Cursor in text mode always blinks (hw
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limitation).
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blink - enables cursor blinking. It is default.
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nofastfont - disables fastfont feature. It is default.
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fastfont:X - enables fastfont feature. X specifies size of memory reserved for
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font data, it must be >= (fontwidth*fontheight*chars_in_font)/8.
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It is faster on Gx00 series, but slower on older cards.
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grayscale - enable grayscale summing. It works in PSEUDOCOLOR modes (text,
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4bpp, 8bpp). In DIRECTCOLOR modes it is limited to characters
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displayed through putc/putcs. Direct accesses to framebuffer
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can paint colors.
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nograyscale - disable grayscale summing. It is default.
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cross4MB - enables that pixel line can cross 4MB boundary. It is default for
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non-Millenium.
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nocross4MB - pixel line must not cross 4MB boundary. It is default for
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Millenium I or II, because of these devices have hardware
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limitations which do not allow this. But this option is
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incompatible with some (if not all yet released) versions of
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XF86_FBDev.
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dfp - enables digital flat panel interface. This option is incompatible with
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secondary (TV) output - if DFP is active, TV output must be
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inactive and vice versa. DFP always uses same timing as primary
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(monitor) output.
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dfp:X - use settings X for digital flat panel interface. X is number from
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0 to 0xFF, and meaning of each individual bit is described in
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G400 manual, in description of DAC register 0x1F. For normal operation
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you should set all bits to zero, except lowest bit. This lowest bit
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selects who is source of display clocks, whether G400, or panel.
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Default value is now read back from hardware - so you should specify
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this value only if you are also using `init' parameter.
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outputs:XYZ - set mapping between CRTC and outputs. Each letter can have value
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of 0 (for no CRTC), 1 (CRTC1) or 2 (CRTC2), and first letter corresponds
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to primary analog output, second letter to the secondary analog output
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and third letter to the DVI output. Default setting is 100 for
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cards below G400 or G400 without DFP, 101 for G400 with DFP, and
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111 for G450 and G550. You can set mapping only on first card,
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use matroxset for setting up other devices.
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vesa:X - selects startup videomode. X is number from 0 to 0x1FF, see table
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above for detailed explanation. Default is 640x480x8bpp if driver
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has 8bpp support. Otherwise first available of 640x350x4bpp,
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640x480x15bpp, 640x480x24bpp, 640x480x32bpp or 80x25 text
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(80x25 text is always available).
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If you are not satisfied with videomode selected by `vesa' option, you
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can modify it with these options:
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xres:X - horizontal resolution, in pixels. Default is derived from `vesa'
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option.
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yres:X - vertical resolution, in pixel lines. Default is derived from `vesa'
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option.
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upper:X - top boundary: lines between end of VSYNC pulse and start of first
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pixel line of picture. Default is derived from `vesa' option.
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lower:X - bottom boundary: lines between end of picture and start of VSYNC
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pulse. Default is derived from `vesa' option.
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vslen:X - length of VSYNC pulse, in lines. Default is derived from `vesa'
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option.
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left:X - left boundary: pixels between end of HSYNC pulse and first pixel.
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Default is derived from `vesa' option.
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right:X - right boundary: pixels between end of picture and start of HSYNC
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pulse. Default is derived from `vesa' option.
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hslen:X - length of HSYNC pulse, in pixels. Default is derived from `vesa'
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option.
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pixclock:X - dotclocks, in ps (picoseconds). Default is derived from `vesa'
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option and from `fh' and `fv' options.
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sync:X - sync. pulse - bit 0 inverts HSYNC polarity, bit 1 VSYNC polarity.
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If bit 3 (value 0x08) is set, composite sync instead of HSYNC is
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generated. If bit 5 (value 0x20) is set, sync on green is turned on.
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Do not forget that if you want sync on green, you also probably
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want composite sync.
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Default depends on `vesa'.
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depth:X - Bits per pixel: 0=text, 4,8,15,16,24 or 32. Default depends on
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`vesa'.
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If you know capabilities of your monitor, you can specify some (or all) of
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`maxclk', `fh' and `fv'. In this case, `pixclock' is computed so that
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pixclock <= maxclk, real_fh <= fh and real_fv <= fv.
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maxclk:X - maximum dotclock. X can be specified in MHz, kHz or Hz. Default is
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`don't care'.
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fh:X - maximum horizontal synchronization frequency. X can be specified
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in kHz or Hz. Default is `don't care'.
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fv:X - maximum vertical frequency. X must be specified in Hz. Default is
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70 for modes derived from `vesa' with yres <= 400, 60Hz for
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yres > 400.
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Limitations
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===========
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There are known and unknown bugs, features and misfeatures.
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Currently there are following known bugs:
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+ SVGALib does not restore screen on exit
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+ generic fbcon-cfbX procedures do not work on Alphas. Due to this,
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`noaccel' (and cfb4 accel) driver does not work on Alpha. So everyone
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with access to /dev/fb* on Alpha can hang machine (you should restrict
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access to /dev/fb* - everyone with access to this device can destroy
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your monitor, believe me...).
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+ 24bpp does not support correctly XF-FBDev on big-endian architectures.
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+ interlaced text mode is not supported; it looks like hardware limitation,
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but I'm not sure.
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+ Gxx0 SGRAM/SDRAM is not autodetected.
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+ If you are using more than one framebuffer device, you must boot kernel
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with 'video=scrollback:0'.
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+ maybe more...
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And following misfeatures:
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+ SVGALib does not restore screen on exit.
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+ pixclock for text modes is limited by hardware to
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83 MHz on G200
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66 MHz on Millennium I
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60 MHz on Millennium II
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Because I have no access to other devices, I do not know specific
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frequencies for them. So driver does not check this and allows you to
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set frequency higher that this. It causes sparks, black holes and other
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pretty effects on screen. Device was not destroyed during tests. :-)
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+ my Millennium G200 oscillator has frequency range from 35 MHz to 380 MHz
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(and it works with 8bpp on about 320 MHz dotclocks (and changed mclk)).
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But Matrox says on product sheet that VCO limit is 50-250 MHz, so I believe
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them (maybe that chip overheats, but it has a very big cooler (G100 has
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none), so it should work).
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+ special mixed video/graphics videomodes of Mystique and Gx00 - 2G8V16 and
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G16V16 are not supported
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+ color keying is not supported
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+ feature connector of Mystique and Gx00 is set to VGA mode (it is disabled
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by BIOS)
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+ DDC (monitor detection) is supported through dualhead driver
|
||
|
|
+ some check for input values are not so strict how it should be (you can
|
||
|
|
specify vslen=4000 and so on).
|
||
|
|
+ maybe more...
|
||
|
|
And following features:
|
||
|
|
+ 4bpp is available only on Millennium I and Millennium II. It is hardware
|
||
|
|
limitation.
|
||
|
|
+ selection between 1:5:5:5 and 5:6:5 16bpp videomode is done by -rgba
|
||
|
|
option of fbset: "fbset -depth 16 -rgba 5,5,5" selects 1:5:5:5, anything
|
||
|
|
else selects 5:6:5 mode.
|
||
|
|
+ text mode uses 6 bit VGA palette instead of 8 bit (one of 262144 colors
|
||
|
|
instead of one of 16M colors). It is due to hardware limitation of
|
||
|
|
Millennium I/II and SVGALib compatibility.
|
||
|
|
|
||
|
|
|
||
|
|
Benchmarks
|
||
|
|
==========
|
||
|
|
It is time to redraw whole screen 1000 times in 1024x768, 60Hz. It is
|
||
|
|
time for draw 6144000 characters on screen through /dev/vcsa
|
||
|
|
(for 32bpp it is about 3GB of data (exactly 3000 MB); for 8x16 font in
|
||
|
|
16 seconds, i.e. 187 MBps).
|
||
|
|
Times were obtained from one older version of driver, now they are about 3%
|
||
|
|
faster, it is kernel-space only time on P-II/350 MHz, Millennium I in 33 MHz
|
||
|
|
PCI slot, G200 in AGP 2x slot. I did not test vgacon.
|
||
|
|
|
||
|
|
NOACCEL
|
||
|
|
8x16 12x22
|
||
|
|
Millennium I G200 Millennium I G200
|
||
|
|
8bpp 16.42 9.54 12.33 9.13
|
||
|
|
16bpp 21.00 15.70 19.11 15.02
|
||
|
|
24bpp 36.66 36.66 35.00 35.00
|
||
|
|
32bpp 35.00 30.00 33.85 28.66
|
||
|
|
|
||
|
|
ACCEL, nofastfont
|
||
|
|
8x16 12x22 6x11
|
||
|
|
Millennium I G200 Millennium I G200 Millennium I G200
|
||
|
|
8bpp 7.79 7.24 13.55 7.78 30.00 21.01
|
||
|
|
16bpp 9.13 7.78 16.16 7.78 30.00 21.01
|
||
|
|
24bpp 14.17 10.72 18.69 10.24 34.99 21.01
|
||
|
|
32bpp 16.15 16.16 18.73 13.09 34.99 21.01
|
||
|
|
|
||
|
|
ACCEL, fastfont
|
||
|
|
8x16 12x22 6x11
|
||
|
|
Millennium I G200 Millennium I G200 Millennium I G200
|
||
|
|
8bpp 8.41 6.01 6.54 4.37 16.00 10.51
|
||
|
|
16bpp 9.54 9.12 8.76 6.17 17.52 14.01
|
||
|
|
24bpp 15.00 12.36 11.67 10.00 22.01 18.32
|
||
|
|
32bpp 16.18 18.29* 12.71 12.74 24.44 21.00
|
||
|
|
|
||
|
|
TEXT
|
||
|
|
8x16
|
||
|
|
Millennium I G200
|
||
|
|
TEXT 3.29 1.50
|
||
|
|
|
||
|
|
* Yes, it is slower than Millennium I.
|
||
|
|
|
||
|
|
|
||
|
|
Dualhead G400
|
||
|
|
=============
|
||
|
|
Driver supports dualhead G400 with some limitations:
|
||
|
|
+ secondary head shares videomemory with primary head. It is not problem
|
||
|
|
if you have 32MB of videoram, but if you have only 16MB, you may have
|
||
|
|
to think twice before choosing videomode (for example twice 1880x1440x32bpp
|
||
|
|
is not possible).
|
||
|
|
+ due to hardware limitation, secondary head can use only 16 and 32bpp
|
||
|
|
videomodes.
|
||
|
|
+ secondary head is not accelerated. There were bad problems with accelerated
|
||
|
|
XFree when secondary head used to use acceleration.
|
||
|
|
+ secondary head always powerups in 640x480@60-32 videomode. You have to use
|
||
|
|
fbset to change this mode.
|
||
|
|
+ secondary head always powerups in monitor mode. You have to use fbmatroxset
|
||
|
|
to change it to TV mode. Also, you must select at least 525 lines for
|
||
|
|
NTSC output and 625 lines for PAL output.
|
||
|
|
+ kernel is not fully multihead ready. So some things are impossible to do.
|
||
|
|
+ if you compiled it as module, you must insert i2c-matroxfb, matroxfb_maven
|
||
|
|
and matroxfb_crtc2 into kernel.
|
||
|
|
|
||
|
|
|
||
|
|
Dualhead G450
|
||
|
|
=============
|
||
|
|
Driver supports dualhead G450 with some limitations:
|
||
|
|
+ secondary head shares videomemory with primary head. It is not problem
|
||
|
|
if you have 32MB of videoram, but if you have only 16MB, you may have
|
||
|
|
to think twice before choosing videomode.
|
||
|
|
+ due to hardware limitation, secondary head can use only 16 and 32bpp
|
||
|
|
videomodes.
|
||
|
|
+ secondary head is not accelerated.
|
||
|
|
+ secondary head always powerups in 640x480@60-32 videomode. You have to use
|
||
|
|
fbset to change this mode.
|
||
|
|
+ TV output is not supported
|
||
|
|
+ kernel is not fully multihead ready, so some things are impossible to do.
|
||
|
|
+ if you compiled it as module, you must insert matroxfb_g450 and matroxfb_crtc2
|
||
|
|
into kernel.
|
||
|
|
|
||
|
|
--
|
||
|
|
Petr Vandrovec <vandrove@vc.cvut.cz>
|