Mod so GRUB works on systems w/ no video card

[Eric Malkowski]

I'm posting this to see if anyone's interested in a simple mod I made to
grub 0.92 that allows grub to boot a system w/ no video board taking
advantage of grub's serial port capabilities.

I basically disabled output to the screen via INT calls in stage1 and
stage1.5.

On my system that has no video board, it would hang when stage 1 tried
to use an INT call to write to a non-existent VGA BIOS.

With the mods in place, nothing is written to the VGA screen and the
first sign of life from GRUB is the "press any key" messages on the
serial port.  Then you get the GRUB menu and can boot for instance the
linux kernel with serial console enabled.  If a video board is
installed, you simply see nothing on it with this mod to GRUB.

Three files were modified to disable MSG(x) macros and a printf.

The only disadvantage to this is you don't get to see any possible early
stage1 or stage1.5 error messages.  The idea is to get everything
working w/ video enabled and when you're ready to run w/o video,
re-build grub w/ my changes.

I was thinking a configure option could be added like "--no-vga" or
something to build GRUB with no output to VGA for folks like me that
want to run w/ no video board.

Let me know and I will make a formalized patch against 0.92 with the new
configure option.  I wanted to see if anyone wanted this before I make a
patch.

GRUB turned out to be an excellent solution to boot linux on our
"video-less" boards for testing.

--
Eric Malkowski
Principal Software Engineer
ADC - The Broadband Company