$Id: pvr2fb.txt,v 1.1 2012/04/09 18:02:23 pradev Exp $

What is pvr2fb?
===============

This is a driver for PowerVR 2 based graphics frame buffers, such as the
one found in the Dreamcast.

Advantages:

 * It provides a nice large console (128 cols + 48 lines with 1024x768)
   without using tiny, unreadable fonts (NOT on the Dreamcast)
 * You can run XF86_FBDev on top of /dev/fb0
 * Most important: boot logo :-)

Disadvantages:

 * Driver is largely untested on non-Dreamcast systems.

Configuration
=============

You can pass kernel command line options to pvr2fb with
`video=pvr2fb:option1,option2:value2,option3' (multiple options should be
separated by comma, values are separated from options by `:').
Accepted options:

font:X    - default font to use. All fonts are supported, including the
            SUN12x22 font which is very nice at high resolutions.

	    
mode:X    - default video mode with format [xres]x[yres]-<bpp>@<refresh rate>
            The following video modes are supported:
            640x640-16@60, 640x480-24@60, 640x480-32@60. The Dreamcast
            defaults to 640x480-16@60. At the time of writing the
            24bpp and 32bpp modes function poorly. Work to fix that is
            ongoing

            Note: the 640x240 mode is currently broken, and should not be
            used for any reason. It is only mentioned here as a reference.

inverse   - invert colors on screen (for LCD displays)

nomtrr    - disables write combining on frame buffer. This slows down driver
            but there is reported minor incompatibility between GUS DMA and
            XFree under high loads if write combining is enabled (sound
            dropouts). MTRR is enabled by default on systems that have it
            configured and that support it.

cable:X   - cable type. This can be any of the following: vga, rgb, and
            composite. If none is specified, we guess.

output:X  - output type. This can be any of the following: pal, ntsc, and
            vga. If none is specified, we guess.

X11
===

XF86_FBDev has been shown to work on the Dreamcast in the past - though not yet
on any 2.6 series kernel.

--
Paul Mundt <lethal@linuxdc.org>
Updated by Adrian McMenamin <adrian@mcmen.demon.co.uk>

