Re: Restoring videomode on return from S3 sleep

From: Pavel Machek (pavel@suse.cz)
Date: Tue Nov 27 2001 - 13:32:09 EST


Hi!

> > > > I'll need to restore video mode on returning from acpi sleep...
> > > >
> > > > Unfortunately, video selection code is not part of kernel, it is
> > > > 16-bit code. acpi_wakeup.S, otoh, *is* part of kernel :-(.
> > >
> > > Is this on the console and if it is I assum you are uing vgacon. It could
> > > be the S# card has a broken implemenation. This wouldn't be the first.
> > > Their has been a patch sometime for vesafb to work properly with S3 cards.
> > >
> > > S3 framebuffer anyone? I remember their has been scathered work on this
> > > but I never seen anything come to light for this.
> >
> > Oh. Sorry. By S3 I mean ACPI S3 state. ACPI S3 == suspend to RAM.
> >
> > Basically what I need is to restore video mode after returning from
> > ACPI S3 sleep state, so that vesafb works properly.
>
> I need the same for APM. (I would prefer ACPI, but it currently
> hangs by box)

ACPI and APM are *very* different in this regard: in APM, you stay
protected mode, while with ACPI, you *have to* go through real mode.

> I have to use vesafb or I get artifacts (Trident CyberBlade/XP), but then a
> resume from APM never restores the video. Presumably, a reset (similar to
> when the fb is turned on?) would fix the problem. I haven't looked into it
> yet due to lack of time, but if someone else is going to work on it, I'll
> gladly help test.

It is going to be different from ACPI sleep support.

...or...

maybe not. vesafb with ability to go back realmode and reinit hw would
be nice -- and it would also fix your APM problem. But I doubt that's
implementable.
                                                                        Pavel

-- 
Casualities in World Trade Center: 6453 dead inside the building,
cryptography in U.S.A. and free speech in Czech Republic.
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This archive was generated by hypermail 2b29 : Fri Nov 30 2001 - 21:00:28 EST