[PATCH] Good bye vm86, hello x86 real mode ;-)

[Stefan Reinauer]

See patch. The subject is a bit misleading, since we never used vm86
mode in coreboot.

Stefan

[Joseph Smith]

On Tue, 26 May 2009 14:49:42 +0200, Stefan Reinauer 
wrote:
> See patch. The subject is a bit misleading, since we never used vm86
> mode in coreboot.

Great Job Stefan. I really like this, but I would like to test it out
before an Ack.

[ron minnich]

Let's get some testing done but I love this code.

BTW, in this file:
+ *  Erik Arjan Hendriks 
+ *  Copyright (C) 2000 Scyld.
+ *  Copyright (C) 2000 Scyld Computing Corporation

There's not a single line of code left that was contributed by Erik.
What do we do in this case, where the
original code is long gone? I used Erik's code for the switch to/from
32-bit mode, but the rest was my stuff copyright 2001.

ron

[Uwe Hermann]

On Tue, May 26, 2009 at 07:23:06AM -0700, ron minnich wrote:
> Let's get some testing done but I love this code.
>
> BTW, in this file:
> Erik Arjan Hendriks
> Copyright (C) 2000 Scyld.
> Copyright (C) 2000 Scyld Computing Corporation
>
> There's not a single line of code left that was contributed by Erik.
> What do we do in this case, where the
> original code is long gone?

If the code from one author is gone, the respective copyright line
should also be removed, of course.

Uwe.

[Peter Stuge]

Stefan Reinauer wrote:
> drop most of the crappy vm86 code and replace it with a rewritten
> version that has all assembler in a .S file and all C code in a .c
> file. Also, remove requirement to move around between GDTs.
>
> Signed-off-by: Stefan Reinauer
> +++ util/x86emu/x86_asm.S	(revision 0)

..
> movl	%cr0, %eax
> andl	$0xFFFFFFFE, %eax
> movl	%eax, %cr0
> movl	%cr0, %eax
> orl	$0x0000001, %eax /* PE = 1 */
> movl	%eax, %cr0
> movl	%cr0, %eax
> andl	$~1, %eax
> movl	%eax, %cr0
> movl	%cr0, %eax
> orl	$(1 << 0), %eax
> movl	%eax, %cr0
> movl    %cr0, %eax
> orl	$(1 << 0), %eax
> movl	%eax, %cr0
> movl	%cr0, %eax
> andl	$~(1 << 0), %eax
> movl	%eax, %cr0

It would be neat if these different ways of changing PE could be
streamlined a little.

And could it be good to cli/sti around the PE changes?

If not;

Acked-by: Peter Stuge

[Joseph Smith]

On Tue, 26 May 2009 14:49:42 +0200, Stefan Reinauer 
wrote:
> See patch. The subject is a bit misleading, since we never used vm86
> mode in coreboot.

Should we rename the option CONFIG_PCI_OPTION_ROM_RUN_VM86 to
CONFIG_PCI_OPTION_ROM_RUN_X86 ?

[Stefan Reinauer]

On 29.05.2009 17:59 Uhr, Joseph Smith wrote:
> On Tue, 26 May 2009 14:49:42 +0200, Stefan Reinauer 
> wrote:
> > See patch. The subject is a bit misleading, since we never used vm86
> > mode in coreboot.
>
> Should we rename the option CONFIG_PCI_OPTION_ROM_RUN_VM86 to
> CONFIG_PCI_OPTION_ROM_RUN_X86 ?

possibly... or "native" or "real_mode" ?

[Peter Stuge]

Stefan Reinauer wrote:
> > Should we rename the option CONFIG_PCI_OPTION_ROM_RUN_VM86 to
> > CONFIG_PCI_OPTION_ROM_RUN_X86 ?
>
> possibly... or "native" or "real_mode" ?

Yes please, something with real mode.

//Peter

[Joseph Smith]

On Sat, 30 May 2009 06:20:12 +0200, Peter Stuge  wrote:
> Stefan Reinauer wrote:
> > > Should we rename the option CONFIG_PCI_OPTION_ROM_RUN_VM86 to
> > > CONFIG_PCI_OPTION_ROM_RUN_X86 ?
> >
> > possibly... or "native" or "real_mode" ?
>
> Yes please, something with real mode.

Already done r4325 and r1170
Renamed to CONFIG_PCI_OPTION_ROM_RUN_REALMODE.