
	s3fb - fbdev driver for S3 Trio/Virge chips
	===========================================


Supported Hardware
==================

	S3 Trio32
	S3 Trio64 (and variants V+, UV+, V2/DX, V2/GX)
	S3 Virge  (and variants VX, DX, GX and GX2+)
	S3 Plato/PX		(completely untested)
	S3 Aurora64V+		(completely untested)

	- only PCI bus supported
	- only BIOS initialized VGA devices supported
	- probably not working on big endian

I tested s3fb on Trio64 (plain, V+ and V2/DX) and Virge (plain, VX, DX),
all on i386.


Supported Features
==================

	*  4 bpp pseudocolor modes (with 18bit palette, two variants)
	*  8 bpp pseudocolor mode (with 18bit palette)
	* 16 bpp truecolor modes (RGB 555 and RGB 565)
	* 24 bpp truecolor mode (RGB 888) on (only on Virge VX)
	* 32 bpp truecolor mode (RGB 888) on (not on Virge VX)
	* text mode (activated by bpp = 0)
	* interlaced mode variant (not available in text mode)
	* doublescan mode variant (not available in text mode)
	* panning in both directions
	* suspend/resume support
	* DPMS support

Text mode is supported even in higher resolutions, but there is limitation
to lower pixclocks (maximum between 50-60 MHz, depending on specific hardware).
This limitation is not enforced by driver. Text mode supports 8bit wide fonts
only (hardware limitation) and 16bit tall fonts (driver limitation).

There are two 4 bpp modes. First mode (selected if nonstd == 0) is mode with
packed pixels, high nibble first. Second mode (selected if nonstd == 1) is mode
with interleaved planes (1 byte interleave), MSB first. Both modes support
8bit wide fonts only (driver limitation).

Suspend/resume works on systems that initialize video card during resume and
if device is active (for example used by fbcon).


Missing Features
================
(alias TODO list)

	* secondary (not initialized by BIOS) device support
   	* big endian support
	* Zorro bus support
	* MMIO support
	* 24 bpp mode support on more cards
	* support for fontwidths != 8 in 4 bpp modes
	* support for fontheight != 16 in text mode
	* composite and external sync (is anyone able to test this?)
	* hardware cursor
	* video overlay support
	* vsync synchronization
	* feature connector support
	* acceleration support (8514-like 2D, Virge 3D, busmaster transfers)
	* better values for some magic registers (performance issues)


Known bugs
==========

	* cursor disable in text mode doesn't work

--
Ondrej Zajicek <santiago@crfreenet.org>
