Re: Disabling ACPI also implicitly disables SMP support for Intel Atom chips?

[Andrew Doran <ad%netbsd.org@localhost>]

On Wed, Mar 04, 2009 at 05:18:23PM -0500, Jared D. McNeill wrote:
> David H. Gutteridge wrote:
> >Hi all,
> >
> >Is it a given that disabling ACPI also disables SMP (well, really SMT,
> >technically) with Intel Atom chips?  (Or others?)  The i386 boot prompt
> >offers the choice of disabling ACPI only, but when I choose it on my
> >LG X110 netbook, the kernel doesn't recognize the HT capabilities of
> >the CPU.  In order to get SMP, I have to enable ACPI.  Is this
> >something I should PR, or is it just the nature of things here?  (This
> >is with 5.0 RC2, incidentally.)
> 
> Does your motherboard have MP BIOS extensions (the fallback when ACPI 
> isn't enabled)? I suspect not.

I have found that the trend is to report HT via ACPI but not via MPBIOS.
Dual cores tend to show up via MPBIOS.

David, what's the issue with ACPI?

Andrew