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+
+Introduction
+
+	  This is a frame buffer device driver for 3dfx' Voodoo Graphics 
+	(aka voodoo 1, aka sst1) and Voodoo² (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 3d²" 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 usable
+	(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... 
+
+
+Installation 
+
+	  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 from 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
+	  directly 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 options to the 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 following 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 discarded.
+				Default: enable clipping.
+
+gfxclk=x	gfxclk:x	Force graphic clock frequency (in MHz).
+				Be careful with this option, it may be
+				DANGEROUS.
+				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)
+
+Tools
+
+	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 .
+
+Bugs
+
+	- 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 -> basically the blue component and 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 specifically 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 things in 24/32 bpp.
+	- When used with another video board, current limitations of the linux
+	console subsystem can cause some troubles, specifically, you should
+	disable software scrollback, as it can oops badly ...
+
+Todo
+
+	- 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 actually do a 
+	  lot in 2D even if it was sold as a 3D only board ...
+
+ghoz.
+
+-- 
+Ghozlane Toumi <gtoumi@laposte.net>
+
+
+$Date: 2002/05/09 20:11:45 $
+http://sstfb.sourceforge.net/README