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+ This is a frame buffer device driver for 3dfx' Voodoo Graphics
+ (aka voodoo 1, aka sst1) and VoodooČ (aka Voodoo 2, aka CVG) based
+ video boards. It's highly experimental code, but is guaranteed to work
+ on my computer, with my "Maxi Gamer 3D" and "Maxi Gamer 3dČ" boards,
+ and with me "between chair and keyboard". Some people tested other
+ combinations and it seems that it works.
+ The main page is located at <http://sstfb.sourceforge.net>, and if
+ you want the latest version, check out the CVS, as the driver is a work
+ in progress, I feel uncomfortable with releasing tarballs of something
+ not completely working...Don't worry, it's still more than useable
+ (I eat my own dog food)
+ Please read the Bug section, and report any success or failure to me
+ (Ghozlane Toumi <gtoumi@laposte.net>).
+ BTW, If you have only one monitor , and you don't feel like playing
+ with the vga passthrou cable, I can only suggest borrowing a screen
+ somewhere...
+ This driver (should) work on ix86, with "late" 2.2.x kernel (tested
+ with x = 19) and "recent" 2.4.x kernel, as a module or compiled in.
+ It has been included in mainstream kernel since the infamous 2.4.10.
+ You can apply the patches found in sstfb/kernel/*-2.{2|4}.x.patch,
+ and copy sstfb.c to linux/drivers/video/, or apply a single patch,
+ sstfb/patch-2.{2|4}.x-sstfb-yymmdd to your linux source tree.
+ Then configure your kernel as usual: choose "m" or "y" to 3Dfx Voodoo
+ Graphics in section "console". Compile, install, have fun... and please
+ drop me a report :)
+Module Usage
+ Warnings.
+ # You should read completely this section before issuing any command.
+ # If you have only one monitor to play with, once you insmod the
+ module, the 3dfx takes control of the output, so you'll have to
+ plug the monitor to the "normal" video board in order to issue
+ the commands, or you can blindly use sst_dbg_vgapass
+ in the tools directory (See Tools). The latest solution is pass the
+ parameter vgapass=1 when insmodding the driver. (See Kernel/Modules
+ Options)
+ Module insertion:
+ # insmod sstfb.o
+ you should see some strange output frome the board:
+ a big blue square, a green and a red small squares and a vertical
+ white rectangle. why ? the function's name is self explanatory :
+ "sstfb_test()"...
+ (if you don't have a second monitor, you'll have to plug your monitor
+ directely to the 2D videocard to see what you're typing)
+ # con2fb /dev/fbx /dev/ttyx
+ bind a tty to the new frame buffer. if you already have a frame
+ buffer driver, the voodoo fb will likely be /dev/fb1. if not,
+ the device will be /dev/fb0. You can check this by doing a
+ cat /proc/fb. You can find a copy of con2fb in tools/ directory.
+ if you don't have another fb device, this step is superfluous,
+ as the console subsystem automagicaly binds ttys to the fb.
+ # switch to the virtual console you just mapped. "tadaaa" ...
+ Module removal:
+ # con2fb /dev/fbx /dev/ttyx
+ bind the tty to the old frame buffer so the module can be removed.
+ (how does it work with vgacon ? short answer : it doesn't work)
+ # rmmod sstfb
+Kernel/Modules Options
+ You can pass some otions to sstfb module, and via the kernel command
+ line when the driver is compiled in :
+ for module : insmod sstfb.o option1=value1 option2=value2 ...
+ in kernel : video=sstfb:option1,option2:value2,option3 ...
+ sstfb supports the folowing options :
+Module Kernel Description
+vgapass=0 vganopass Enable or disable VGA passthrou cable.
+vgapass=1 vgapass When enabled, the monitor will get the signal
+ from the VGA board and not from the voodoo.
+ Default: nopass
+mem=x mem:x Force frame buffer memory in MiB
+ allowed values: 0, 1, 2, 4.
+ Default: 0 (= autodetect)
+inverse=1 inverse Supposed to enable inverse console.
+ doesn't work yet...
+clipping=1 clipping Enable or disable clipping.
+clipping=0 noclipping With clipping enabled, all offscreen
+ reads and writes are disgarded.
+ Default: enable clipping.
+gfxclk=x gfxclk:x Force graphic clock frequency (in MHz).
+ Be carefull with this option, it may be
+ Default: auto
+ 50Mhz for Voodoo 1,
+ 75MHz for Voodoo 2.
+slowpci=1 fastpci Enable or disable fast PCI read/writes.
+slowpci=1 slowpci Default : fastpci
+dev=x dev:x Attach the driver to device number x.
+ 0 is the first compatible board (in
+ lspci order)
+ These tools are mostly for debugging purposes, but you can
+ find some of these interesting :
+ - con2fb , maps a tty to a fbramebuffer .
+ con2fb /dev/fb1 /dev/tty5
+ - sst_dbg_vgapass , changes vga passthrou. You have to recompile the
+ driver with SST_DEBUG and SST_DEBUG_IOCTL set to 1
+ sst_dbg_vgapass /dev/fb1 1 (enables vga cable)
+ sst_dbg_vgapass /dev/fb1 0 (disables vga cable)
+ - glide_reset , resets the voodoo using glide
+ use this after rmmoding sstfb, if the module refuses to
+ reinsert .
+ - DO NOT use glide while the sstfb module is in, you'll most likely
+ hang your computer.
+ - If you see some artefacts (pixels not cleaning and stuff like that),
+ try turning off clipping (clipping=0), and/or using slowpci
+ - the driver don't detect the 4Mb frame buffer voodoos, it seems that
+ the 2 last Mbs wrap around. looking into that .
+ - The driver is 16 bpp only, 24/32 won't work.
+ - The driver is not your_favorite_toy-safe. this includes SMP...
+ [Actually from inspection it seems to be safe - Alan]
+ - when using XFree86 FBdev (X over fbdev) you may see strange color
+ patterns at the border of your windows (the pixels lose the lowest
+ byte -> basicaly the blue component nd some of the green) . I'm unable
+ to reproduce this with XFree86-3.3, but one of the testers has this
+ problem with XFree86-4. apparently recent Xfree86-4.x solve this
+ problem.
+ - I didn't really test changing the palette, so you may find some weird
+ things when playing with that.
+ - Sometimes the driver will not recognise the DAC , and the
+ initialisation will fail. this is specificaly true for
+ voodoo 2 boards , but it should be solved in recent versions. please
+ contact me .
+ - the 24/32 is not likely to work anytime soon , knowing that the
+ hardware does ... unusual thigs in 24/32 bpp
+ - When used with anther video board, current limitations of linux
+ console subsystem can cause some troubles, specificaly, you should
+ disable software scrollback , as it can oops badly ...
+ - Get rid of the previous paragraph.
+ - Buy more coffee.
+ - test/port to other arch.
+ - try to add panning using tweeks with front and back buffer .
+ - try to implement accel on voodoo2 , this board can actualy do a
+ lot in 2D even if it was sold as a 3D only board ...
+Ghozlane Toumi <gtoumi@laposte.net>
+$Date: 2002/05/09 20:11:45 $