.\"	$NetBSD: tdvfb.4,v 1.8 2015/02/11 00:11:58 rkujawa Exp $
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.\" Copyright (c) 2012 Radoslaw Kujawa
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.Dd August 3, 2012
.Dt TDVFB 4
.Os
.Sh NAME
.Nm tdvfb
.Nd 3Dfx Voodoo Graphics / Voodoo 2 framebuffer driver
.Sh SYNOPSIS
.Cd "tdvfb* at pci?"
.Cd "wsdisplay* at tdvfb?"
.Cd "options TDVFB_CONSOLE"
.Sh DESCRIPTION
The
.Nm
driver provides support for the graphics cards based on 3Dfx Voodoo Graphics
(SST-1) and 3Dfx Voodoo2 (CVG) chipsets and provides an interface for the
machine independent
.Xr wscons 4
driver.
.Pp
Since both Voodoo Graphics and Voodoo2 were originally designed as a 3D-only
solutions, most boards do not have any kind of firmware.
The
.Nm
driver is able to do low level initialization (boot) of the board, which means
that it can be used on all architectures and is truly machine independent.
However, it also means that driver cannot detect automatically if the card
is used as a console.
The
.Dv TDVFB_CONSOLE
option is provided and should be set if the
.Nm
driver is intended to be used as a console.
.Sh SEE ALSO
.Xr genfb 4 ,
.Xr voodoofb 4 ,
.Xr wsdisplay 4
.Rs
.%A 3Dfx Interactive, Inc.
.%T Voodoo2 Graphics Engine for 3D Game Acceleration
.%N Revision 1.16
.%D December 1, 1999
.Re
.Sh HISTORY
The
.Nm
device first appeared in
.Nx 7.0 .
.Sh AUTHORS
.An -nosplit
The
.Nm
driver was written by
.An Radoslaw Kujawa .
3Dfx Glide 2.x source code, Linux driver by
.An Ghozlane Toumi
were used as reference.
The
.Xr wscons 4
attachment code is based mostly on the
.Xr genfb 4
driver by
.An Michael Lorenz .
.Sh BUGS
3Dfx Voodoo2 has a simple 2D graphics engine.
The
.Nm
driver has minimal support
for this engine.
It is activated only when the card is running in a 16-bit mode
(this is a hardware limitation).
.Pp
Video mode is hard-coded to 800x600 at 60Hz.
Default bit depth for little
endian machines is 16-bit, for big endian machines it is 32-bit.
Resolution and
depth should be selectable at least via kernel configuration file.
It is not
possible to detect what resolutions are supported by the monitor, since Voodoo
Graphics and Voodoo2 have no DDC interface.
.Pp
8-bit depth is not supported by the hardware.
16-bit depth is supported by the hardware and is the preferred depth, however it
does not work correctly on big endian machines at the moment (this is a driver
problem).