From: Gerd Knorr <kraxel@suse.de>

The patch below fixes some vesafb issues.  Changes:

* fixed struct screen_info in tty.h to use portable types.  "unsigned
  long" for 32bit values doesn't work on hammer machines ...

* limited the framebuffer memory used by vesafb to 16 MB.  This avoids
  that vesafb's ioremap() eats plenty of kernel address space for no real
  benefit if the gfx card has very much memory (some have 128 MB or more,
  ia32 has 128 MB address space for vmalloc and ioremap ...).

* mtrr is enabled by default.  That should improve the vesafb performance
  a lot.  Also added a option to disable mtrr.