amd64/94896: Where support VESA Modes for AMD64 kernel ?

[Andrew Reilly]

The following reply was made to PR amd64/94896; it has been noted by GNATS.

From: Andrew Reilly <andrew-freebsd at areilly.bpc-users.org>
To: Oliver Fromme <olli at lurza.secnetix.de>
Cc: Michael Vince <mv at thebeastie.org>, freebsd-amd64 at FreeBSD.ORG,
  bug-followup at FreeBSD.ORG, hhc at tut.by
Subject: Re: amd64/94896: Where support VESA Modes for AMD64 kernel ?
Date: Mon, 10 Apr 2006 20:37:52 +1000

 On Sun, Apr 09, 2006 at 07:05:14PM +0200, Oliver Fromme wrote:
 > I don't know what kind of "hi-res console mode" you have
 > seen on Gentoo, and I don't know what Gentoo might be doing
 > to enable such a thing.  Maybe they have implemented direct
 > support for certain graphics hardware (like KGI), or maybe
 > they switch to VESA mode before switching to amd64 mode.
 > 
 > However, there is no way to call the x86 VESA BIOS in amd64
 > ("long") mode, because amd64 has no vm86 mode.  It does not
 > work, and Gentoo certainly doesn't do that either.
 
 I don't know how Gentoo does it either, but I was thinking
 about this the other day, and wondered how possible it might be
 to write simple (non-fast) real-mode x86 emulator/interpreter
 (which could perhaps be unloaded when finished), just for this
 sort of thing.  It wouldn't need to emulate hardware, which is
 what takes up a lot of complexity in systems like bochs, because
 you want the emulated code to frob the real hardware: that's the
 point.
 
 I have a vague recollection that Sun (and Apple?, and DEC?) had
 to do this sort of thing for their Sparc and PowerPC systems
 when they started building PCI systems around their non-x86
 processors.
 
 Might even make ia32 systems neater, because you wouldn't need
 to muck about with vm86 mode to get those jobs done.
 
 -- 
 Andrew