Some issues with VBE support.

["Vesa Jääskeläinen" <chaac@nic.fi>]

Hi,

I have been working (slowly) on new module for GRUB2 to add support for 
VBE. I have run to some addressing problems so I though I could ask here 
if someone can give an advice.

Running under DPMI host I could use it's services to map frame buffer's 
physical memory address. (using DPMI function 0x800)

So how could this be done in grub?

Otherwise I have already implemented all needed real mode stubs to call 
VBE. I implemented these to kern/i386/pc/startup.S as there were 
existing helpers for VGA.

Can GRUB_MEMORY_MACHINE_SCRATCH_ADDR be used freely on this context? I 
need to some low memory addresses to get information from VBE. For now I 
have used this and it seems to work correctly, but there could be some 
issues that I don't see now?

Thanks,
Vesa Jääskeläinen