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diff --git a/Documentation/fb/sstfb.rst b/Documentation/fb/sstfb.rst new file mode 100644 index 000000000000..8e8c1b940359 --- /dev/null +++ b/Documentation/fb/sstfb.rst @@ -0,0 +1,207 @@ +===== +sstfb +===== + +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 +============ + +.. warning:: + + #. 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 ... + +Ghozlane Toumi <gtoumi@laposte.net> + + +Date: 2002/05/09 20:11:45 + +http://sstfb.sourceforge.net/README |