FreeBSD 8.0 hangs on boot with ACPI enabled

[John Baldwin]

On Wednesday 30 December 2009 9:39:43 am Joerg Wunsch wrote:
> As John Baldwin wrote:
> 
> > I'm guessing that ahc0 doesn't like the the I/O port resource range
> > it was assigned in the ACPI case.  No idea why ACPI would clobber
> > that BAR.
> 
> Hmm, indeed, I've been using a differen HBA in the past.  Do you think
> it would make sense using another HBA, like a Tekram one?  I could
> easily swap them.
> 
> Anyway, the ahc0 at least can still find the attached drives while the
> BIOS is running (otherwise it wouldn't boot at all).  Isn't it using
> the very same IO addresses then as FreeBSD with ACPI enabled?

No, when ACPI is enabled the BAR is getting reset to 0 for some reason after 
the boot has started and FreeBSD tries to guess at an address to use.  
Unfortunately it picks an address that doesn't work.  This is fixable, it's 
just part of the much larger PCI resource management problem.

OTOH, I'm not sure why initializing ACPI is trashing the BAR.  If you want, 
you can try to narrow down at what point the BAR gets reset to 0.

-- 
John Baldwin