Intel 830M/845G/852GM/855GM/865G/915G/945G Framebuffer driver

  ================================================================
  
  A. Introduction

  	This is a framebuffer driver for various Intel 8xx/9xx compatible

  graphics devices.  These would include:
  
  	Intel 830M

  	Intel 845G

  	Intel 852GM
  	Intel 855GM
  	Intel 865G
  	Intel 915G

  	Intel 915GM
  	Intel 945G
  	Intel 945GM

  	Intel 945GME

  	Intel 965G
  	Intel 965GM

  
  B.  List of available options
  
     a. "video=intelfb"
  	enables the intelfb driver
  
  	Recommendation: required
  
     b. "mode=<xres>x<yres>[-<bpp>][@<refresh>]"
  	select mode
  
  	Recommendation: user preference
  	(default = 1024x768-32@70)
  
     c. "vram=<value>"
  	select amount of system RAM in MB to allocate for the video memory
  	if not enough RAM was already allocated by the BIOS.
  
  	Recommendation: 1 - 4 MB.
  	(default = 4 MB)
  
     d. "voffset=<value>"
          select at what offset in MB of the logical memory to allocate the
  	framebuffer memory.  The intent is to avoid the memory blocks
  	used by standard graphics applications (XFree86). Depending on your
          usage, adjust the value up or down, (0 for maximum usage, 63/127 MB
          for the least amount).  Note, an arbitrary setting may conflict
          with XFree86.
  
  	Recommendation: do not set
  	(default = 48 MB)
  
     e. "accel"
  	enable text acceleration.  This can be enabled/reenabled anytime
  	by using 'fbset -accel true/false'.
  
  	Recommendation: enable
  	(default = set)
  
     f. "hwcursor"
  	enable cursor acceleration.
  
  	Recommendation: enable
  	(default = set)
  
     g. "mtrr"
  	enable MTRR.  This allows data transfers to the framebuffer memory
  	to occur in bursts which can significantly increase performance.
  	Not very helpful with the intel chips because of 'shared memory'.
  
  	Recommendation: set
  	(default = set)
  
     h. "fixed"
  	disable mode switching.
  
  	Recommendation: do not set
  	(default = not set)
  
     The binary parameters can be unset with a "no" prefix, example "noaccel".
     The default parameter (not named) is the mode.
  
  C. Kernel booting
  
  Separate each option/option-pair by commas (,) and the option from its value
  with an equals sign (=) as in the following:

  video=intelfb:option1,option2=value2

  
  Sample Usage
  ------------
  
  In /etc/lilo.conf, add the line:

  append="video=intelfb:mode=800x600-32@75,accel,hwcursor,vram=8"

  
  This will initialize the framebuffer to 800x600 at 32bpp and 75Hz. The
  framebuffer will use 8 MB of System RAM. hw acceleration of text and cursor
  will be enabled.

  Remarks
  -------
  
  If setting this parameter doesn't work (you stay in a 80x25 text-mode),
  you might need to set the "vga=<mode>" parameter too - see vesafb.txt
  in this directory.

  D.  Module options
  
  	The module parameters are essentially similar to the kernel
  parameters. The main difference is that you need to include a Boolean value
  (1 for TRUE, and 0 for FALSE) for those options which don't need a value.
  
  Example, to enable MTRR, include "mtrr=1".
  
  Sample Usage
  ------------
  
  Using the same setup as described above, load the module like this:
  
  	modprobe intelfb mode=800x600-32@75 vram=8 accel=1 hwcursor=1

  Or just add the following to a configuration file in /etc/modprobe.d/

  
  	options intelfb mode=800x600-32@75 vram=8 accel=1 hwcursor=1
  
  and just do a
  
  	modprobe intelfb
  
  
  E.  Acknowledgment:
  
  	1.  Geert Uytterhoeven - his excellent howto and the virtual
                                   framebuffer driver code made this possible.
  
  	2.  Jeff Hartmann for his agpgart code.
  
  	3.  David Dawes for his original kernel 2.4 code.
  
  	4.  The X developers.  Insights were provided just by reading the
  	    XFree86 source code.
  
  	5.  Antonino A. Daplas for his inspiring i810fb driver.
  
  	6.  Andrew Morton for his kernel patches maintenance.
  
  ###########################
  Sylvain