From owner-freebsd-drivers@FreeBSD.ORG  Wed Oct 22 06:46:56 2008
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Date: Wed, 22 Oct 2008 12:16:54 +0530
From: Srinivas <mboxindia@gmail.com>
To: freebsd-drivers@freebsd.org
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Subject: [Info] Device detection
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Hello,

I have been very curious about how devices are detected in a system
under FreeBSD ...

AFAIK, root_bus is added during system startup through
"SI_SUB_DRIVERS" subsystem of SYSINIT mechanism.

After that how the buses are detected and added and how the devices
under each bus are detected and added to the kernel.

Could someone plz explain or point out a link which has the explanation.

Thanks for your time,
Srinivas