acpi doc misconfusion...

[kama]

On Fri, 2 Oct 2009, Kevin Oberman wrote:

> > Date: Fri, 02 Oct 2009 19:30:58 +0400
> > From: "Marat N.Afanasyev" <amarat at ksu.ru>
> > Sender: owner-freebsd-stable at freebsd.org
> >
> > kama wrote:
> > > Hi,
> > >
> > > there are a lot of different errors in various document regarding acpi
> > > that are wrong.
> > >
> > > In 'man acpi' it says that 'hint.acpi.0.disabled' should be placed in
> > > loader.conf.
> > >
> > > -------------
> > > LOADER TUNABLES
> > >      Tunables can be set at the loader(8) prompt before booting the kernel
> > > or
> > >      stored in /boot/loader.conf.  Many of these tunables also have a
> > > matching
> > >      sysctl(8) entry for access after boot.
> > > ...
> > >      hint.acpi.0.disabled
> > >              Set this to 1 to disable all of ACPI.  If ACPI has been
> > > disabled
> > >              on your system due to a blacklist entry for your BIOS, you
> > > can
> > >              set this to 0 to re-enable ACPI for testing.
> > > ...
> > > -------------
> > >
> > >
> > >
> > > In 'man loader' it says:
> > > -------------
> > >      acpi_load
> > >                Unset this to disable automatic loading of the ACPI module.
> > >                See also hint.acpi.0.disabled in device.hints(5).
> > > -------------
> > >
> > > In 'man device.hints'
> > > -------------
> > >      The following example disables the ACPI driver:
> > >
> > >            hint.acpi.0.disabled="1"
> > > -------------
> > >
> > > http://www.freebsd.org/doc/en/articles/laptop/article.html page also
> > > states that it should be in device.hints.
> > >
> > >
> > > Well, these are the ones I have found. There are a lot of misconfusion in
> > > various forums what to put where and how its done. Maybe its accurate on
> > > both places, but then that should be noted somewhere.
> > >
> > > /Bjorn
> > >
> > I was told that there's no difference between loader.conf and
> > device.hints, so you can place this option in either file
>
> This is sort of correct. Hints may be placed in either place with the
> same results. But there is a difference on how the files, themselves are
> handled.
>
> /boot/loader.conf is never touched by a FreeBSD update, even for major
> versions. /boot/device.hints is subject to modification between
> versions. It is not automatically updated, but a new version is included
> in the /sys/ARCH/conf directory and an update may be required as drivers
> change. This will delete any custom hints. (E.g. The sio to uart
> transition on 8.0.)
>
> This is why I generally but any hints that really need to survive in
> /boot/loader.conf. (In my case, I have to disable APIC on my laptop.)

But shouldnt this be mentioned somewhere then? To ease the confusion?

/Bjorn