Framebuffer Driver for the CyberVision64 graphics board.

			This driver is to be used with Linux-2.1.35.



	This framebuffer driver has some parts of the NetBSD 1.1/1.2 grf_cv source code included.
I couldn't get any information from S3 and Phase5 so I needed some parts of code from the
NetBSD source tree.
	Now the initialization of the board is done full in Linux so that you no longer need to
boot AmigaDOS in order to use the CyberVision64.
	
	You can boot and use some CyberVision video modes that work with my MicroVitec
multisync monitor. That is done with the video parameter of the boot:
	video=cvision<mode>

	were <mode> can be one of:

	640x480x8
	800x600x8
	1024x768x8
	1152x886x8
	1280x1024x8i	- this mode doesnt work very well at the moment.

	If you need to use a custom mode you can do it by using the custom option in the video
argument like this:

	video=cvision640x480x8,custom:<xres>;<yres>;<pixclock>;<HBS>;<HBE>;<HSS>;<HSE>;<HT>;<VBS>;<VBE>;<VSS>;<VSE>;<VT>

	    xres - Screen Mode Width
	    yres - Screen Mode Height
	pixclock - Pixel Clock in pico seconds.
	     HBS - Horizontal Blank Start
	     HBE - Horizontal Blank End
	     HSS - Horizontal Sync Start
	     HSE - Horizontal Sync End
	      HT - Horizontal Total
	     VBS - Vertical Blank Start
	     VBE - Vertical Blank End
	     VSS - Vertical Sync Start
	     VSE - Vertical Sync End
	      VT - Vertical Total

	for example, a 640x480x8 mode has these parameters:

	pixclock is 25,175 MHz.
	
	pixclock in pico seconds becomes 1E12 / 25.175E9 = 39721.9 -> 39722

	pixclock = 39722
	     HBS = 640
	     HBE = 784
	     HSS = 800
	     HSE = 768
	      HT = 800
	     VBS = 481
	     VBE = 521
	     VSS = 491
	     VSE = 493
	      VT = 525


	INSTALLATION:
		
		  goto your linux source tree root.
		  check that you have the linux-2.1.35 directory and a softlink named linux to
		that directory.
		  extract the linux-2.1.35-cvision-1.0.tgz archive.
		  cd linux
		  make config
		  answer N to the CyberVision support (this is the old driver).
		  answer Y to the CyberVision64 support. (this is my new driver).
		  make dep
		  make clean
		  make
		  Wait many time (in my setup, A4000/68040@25MHz 12MB Ram, CV64) I wait about 2h30m.
		  make the proper /etc/lilo.conf and install the kernel.
		  Have fun :)


	TODO:
		add support for blitting of fonts instead of CPU writes to fbmem.
		add support for 15/16/24 bit screen modes.
		add support for text mode console (I have this but I could only get to work in monochrome for now:( )
		on fly change of video modes with fbset (read as give the driver fbset support :)
		rewrite a XF68_Cyber to use direct calls to graphics board.

	

	Author:
		Antonio Manuel Santos, email: pcl38058@alfa.ist.utl.pt