cvs commit: src/sys/dev/acpica acpi_ec.c

[Nate Lawson]

On Wed, 12 May 2004, Nate Lawson wrote:
> On Thu, 13 May 2004, Takanori Watanabe wrote:
> > In message <200405130317.i4D3H80t098184 at repoman.freebsd.org>, Nate Lawson wrote
> > :
> > >njl         2004/05/12 20:17:08 PDT
> > >
> > >  FreeBSD src repository
> > >
> > >  Modified files:
> > >    sys/dev/acpica       acpi_ec.c
> > >  Log:
> > >  Add support for retrieving _GLK in the ECDT probe.  Now we no longer always
> > >  use the global lock at the beginning of the ECDT probe.  Instead, we use
> > >  the handle from the ECDT to call _GLK.  Also, unify the device description.
> >
> > I think accessing namespace in ECDT probe is incorrect way, because
> > it is expected to call before namespace is initialized.
> >
> > How do you think?
>
> Both NetBSD and FreeBSD call the ECDT probe routine between
> AcpiEnableSubsystem() and AcpiInitializeObjects().  At this point, the
> namespace has been initialized, we just haven't started running.  You are
> correct that the ECDT can be probed even earlier, but it's useful to delay
> it to right before objects are evaluated.
>
> As far as problems this might cause, the only problem would be if _GLK did
> something crazy like accessing an EC opregion or depending on other
> objects to be executed first.  This should never happen since it would
> break Windows XP also.

One more thing:  we already get the handle from the ECDT string using
AcpiGetHandle(), which walks the namespace.

-Nate