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From: Doug Rabson <dfr@nlsystems.com>
To: "M. Warner Losh" <imp@bsdimp.com>
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cc: arch@freebsd.org
Subject: Re: When to burn those bridges
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On Thu, 2003-09-11 at 22:34, M. Warner Losh wrote:
> In message: <1063213147.26798.1.camel@builder02.qubesoft.com>
>             Doug Rabson <dfr@nlsystems.com> writes:
> : My feeling about that was always that the hostb driver provides
> : absolutely no added value in the system. When I was developing agp
> : originally, I just nuked it and kldloading agp.ko worked just fine.
> 
> is that true even on systems with multiple host bridges?

Yes. The host bridges are normally either attached as pcib devices to
the nexus or handled by acpi. The hostb driver just matches against the
pci devices during the toplevel pci scan and then quietens the attach so
that the user doesn't appear to see the device twice.