Re-enabling ACPI module.

[John Baldwin]

On 07-Nov-2003 Takanori Watanabe wrote:
> Hi, I looked in the new APIC code you commit.
> The thing that prevent ACPI subsystem from moduler 
> is the way we aquire ACPI root pointer, I think. Right?

Nope.  It's more complex than that.  We should only use the MADT to enumerate
CPUs if we are using ACPI to route PCI interrupts, so madt can't be standalone,
it needs to be in the ACPI module.  However, modules loaded at boot time don't
get their sysinit's run until SI_SUB_KLD.  However, currently, the SMP code
on i386 probes CPU's at SI_SUB_TUNABLES - 1.  I can fix this, but I am working
on fixing bugs that people are having first.

-- 

John Baldwin <jhb at FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve!"  -  http://www.FreeBSD.org/