[SeaBIOS] [PATCH] lest pretend that RTC can be used to wakeup from S4

[Gleb Natapov]

On Sun, Jan 30, 2011 at 05:25:05PM +0200, Avi Kivity wrote:
> On 01/30/2011 05:23 PM, Gleb Natapov wrote:
> >On Sun, Jan 30, 2011 at 05:15:49PM +0200, Avi Kivity wrote:
> >>  On 01/30/2011 05:13 PM, Gleb Natapov wrote:
> >>  >On Sun, Jan 30, 2011 at 05:08:18PM +0200, Avi Kivity wrote:
> >>  >>   On 01/30/2011 04:34 PM, Gleb Natapov wrote:
> >>  >>   >On Sun, Jan 30, 2011 at 09:29:57AM -0500, Kevin O'Connor wrote:
> >>  >>   >>    On Sun, Jan 30, 2011 at 02:17:11PM +0200, Gleb Natapov wrote:
> >>  >>   >>    >    WHQL complains otherwise.
> >>  >>   >>    >
> >>  >>   >>    >    Signed-off-by: Gleb Natapov<gleb at redhat.com>
> >>  >>   >>
> >>  >>   >>    Can you get this acked by one of the kvm/qemu maintainers?
> >>  >>   >>
> >>  >>   >Avi, Marcelo, Anthony can you look at it?
> >>  >>
> >>  >>   Looks reasonable.  What does the guest need to do to get the RTC to
> >>  >>   wake up the machine?  We may need to add that to the DSDT.
> >>  >>
> >>  >This patch was enough to make WHQL happy. I think Windows talks to RTC
> >>  >directly, not via AML code.
> >>
> >>  What does it do?  Set the alarm?  Is there a way to set the alarm,
> >>  and not cause a wake up, or does the alarm have a 1:1 relationship
> >>  with wakeup?
> >>
> >According to ACPI spec guest needs to set RTC_EN in PM1x_EN register too.
> >If wakeup was caused by RTC alarm RTC_STS will be set in PM1x_STS register.
> >But all this has nothing to do with Seabios.
> 
> In theory a guest could check whether RTC alarm reboot is supported,
> if not it keeps awake, if it is it can set the alarm to sleep.  So
> if seabios lies it could break that guest.
> 
Theoretically possible.

> However that's an unlikely scenario.
> 
I think so too.

--
			Gleb.