Yet another 845G IDE problem

[Rob Speer <rob@twcny.rr.com>]

I can't get DMA to work on an AOpen motherboard using the Intel 845G
chipset. I see in the archives that other people have had problems like
this, and that it's due to a BIOS problem. I've tried some of the
patches that were sent in response, but it seems that those patches are
already incorporated into the kernel I'm using (2.4.20-pre1-ac3) and I
still have the problem.

My kernel command line includes "ide0=dma".

These lines show up on boot:

PCI: Using IRQ router PIIX [8086/24c0] at 00:1f.0
PCI: Found IRQ 11 for device 00:1f.1
...[several unrelated lines]...
Uniform Multi-Platform E-IDE driver Revision: 6.31
ide: Assuming 33MHz system bus speed for PIO modes; override with
idebus=xx
ICH4: IDE controller on PCI bus 00 dev f9
PCI: Device 00:1f.1 not available because of resource collisions
ide: Assuming 33MHz system bus speed for PIO modes; override with
idebus=xx
ide: Assuming 33MHz system bus speed for PIO modes; override with
idebus=xx
ide: Assuming 33MHz system bus speed for PIO modes; override with
idebus=xx
ICH4: IDE controller on PCI bus 00 dev f9
PCI: Device 00:1f.1 not available because of resource collisions
ICH4: (ide_setup_pci_device:) Could not enable device.

And here's what seems to be the relevant part of 'lspci -v':

00:1f.1 IDE interface: Intel Corp. 82801DB ICH4 IDE (rev 01) (prog-if 8a [Master SecP PriP])
	Subsystem: AOPEN Inc.: Unknown device 0074
	Flags: bus master, medium devsel, latency 0, IRQ 11
	I/O ports at <unassigned> [size=8]
	I/O ports at <unassigned> [size=4]
	I/O ports at <unassigned> [size=8]
	I/O ports at <unassigned> [size=4]
	I/O ports at f000 [size=16]
	Memory at 1f800000 (32-bit, non-prefetchable) [size=1K]

-- 
Rob Speer