Re: Still problems with ACPI sleep state

["Michael Frank" <mhf-jjFNsPSvq+iXDw4h08c5KA@public.gmane.org>]

On Fri, 25 Jun 2004 23:30:35 -0700 (PDT), Nate Lawson <nate-Y6VGUYTwhu0@public.gmane.org> wrote:

> [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?
>

No idea, only the BIOS supplier will know the details...
	Michael



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