Re: Still problems with ACPI sleep state

[Nate Lawson <nate-Y6VGUYTwhu0@public.gmane.org>]

[context recovered]
On Sat, 26 Jun 2004, Michael Frank wrote:
> On Fri, 25 Jun 2004 21:15:21 -0700 (PDT), Nate Lawson <nate-Y6VGUYTwhu0@public.gmane.org> wrote:
> > On Fri, 25 Jun 2004, Herman Sheremetyev wrote:
> >> Try booting with acpi_sleep=s3_bios, I had the same problem on my Asus
> >> M6N and that made the LCD come back on after an S3 resume.
> >>
> >> -Herman
> >
> > Could someone familiar with Linux let me know what s3_bios does
> > differently from a normal S3?
> >
> > -Nate
>
> The suspend is performed in the BIOS without OS interaction.
>
> BIOS grabs CPU/its state, suspends devices, saves state,  powers down
> and on powerup restores state, resumes devices, releases its state/CPU.
>
> (more or less)
>
> In short, BIOS does all the work. Used to be like that before ACPI.
> And few systems do it now like that...

I could use a bit more technical response.  For instance, are SLP_TYP_A/B
written to a different register?  If so, which?  Does the system
transition to legacy mode (disabling ACPI), trigger APM suspend, then
re-enable ACPI on resume?  What caveats are there?

-Nate


-------------------------------------------------------
This SF.Net email sponsored by Black Hat Briefings & Training.
Attend Black Hat Briefings & Training, Las Vegas July 24-29 - 
digital self defense, top technical experts, no vendor pitches, 
unmatched networking opportunities. Visit www.blackhat.com