Supporting extension ROMs and beyond...

[Stefan Reinauer]

* ron minnich <rminnich at lanl.gov> [030812 15:39]:
> On Tue, 12 Aug 2003, Stefan Reinauer wrote:
> I wonder if my bug fixes ever made it in. They had some "issues"  (well,
> bugs) with prefix 0x66 instruction parsing.

Don't know, but this version is from 2001. It also does not contain the
latest fixes from xfree (which is using it, too) either.

> > This contains something pretty similar than what we need in the v86bios
> > directory. It's a bios emulation that either plugs into vm86 or x86emu.
> 
> OK you lost me. This is an emulator for the x86, that can parse x86 binary 
> instruction streams, or this is a BIOS emulator? 
 
x86emu in general is the x86 emulator. But the source tar ball comes
with this little program written by the XFree86-Developer Egbert Eich.

* It uses _either_ vm86 mode (on x86 cpus) _or_ x86emu (on non x86 cpus)
  to execute the graphics cards option rom. The cpu code is in either
  x86emu.c or v86.c depending on whether you are on x86 or not.

* it implements an int handler, similar to util/vgabios/ that currently
  only implements int 0x10 and 0x1a. The interrupt handler code is in
  int.c

This application is running in user space, using /dev/mem to access the
rom. When pushing this down to the bios level it could get stripped down
to access the roms and do io directly.

The code is a bit nasty, the Makefile wants to have an s/^\ \ \ \ /\t/
before it works with the gnu make i use and the bison parser does not
compile either, but that is not needed for vbios but only vor the
debugging utilities that Egbert wrote..


Stefan