vgabios: Rewrite vgafb.c graphics operations to set of 4 standard operators.

The vgabios graphics manipulations can all be implemented on top of 4
basic primitives: read 8 pixels, write 8 pixels, move pixels, and
clear pixels.  Implement these four operators for all the graphics
modes and rewrite the graphics functions in vgafb.c to use them.  This
simplifies the graphics code as the high level logic no longer needs
to be implemented for each graphical framebuffer type.

Signed-off-by: Kevin O'Connor <>
2 files changed