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Date: Sun, 9 Feb 1997 13:46:52 -0800 (PST)
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From: mark thompson <thompson@tgsoft.com>
To: questions@freebsd.org
Subject: Intel 82371SB IDE interface
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Probing for devices on PCI bus 0:
chip0 <generic PCI bridge (vendor=%04x device=%04x subclass=%1.2d)> rev 2 on pci0:0
chip1 <Intel 82371SB PCI-ISA bridge> rev 1 on pci0:7:0
chip2 <Intel 82371SB IDE interface> rev 0 on pci0:7:1

wdc0 at 0x1f0-0x1f7 irq 14 on isa
wdc0: unit 0 (wd0): <WDC AC31600H>
wd0: 1549MB (3173184 sectors), 3148 cyls, 16 heads, 63 S/T, 512 B/S

I have a new PCI-bus motherboard. The probe reports (above) reports that
there is an IDE interface on the PCI bus and also a wdc on the isa bus.

I have noticed that in 2.2 there is a driver for the 83271SB:
(sys/pci/wd82371.c) that includes itself iff NPCI > 0. 

So what is going on here? wd82371 creates a piix device that appears to
be a DMA controller. Does the wdc driver magically use this? I simply
fail to see where that is happening.

-mark