[ltp] T43: No DMA for /dev/hdc (Ultrabay Slim HDD)

[Daniel Skorka]

On Fri, Dec 08, 2006 at 07:04:25PM +0800, amateur wrote:
> I didn't use the dvd driver for a long time, but I remember that the
> UltraSlim Slot is a connected to the system with ATAPI interface while 
> the internal hard disk is connected with a SATA interface. It seems

I think you are wrong. The way I understand the explanation on
thinkwiki.org, the UltraBay Slim is 'intelligent' in that it acts
accordingly to what device is inserted in the slot. In fact, I seriously
doubt that you can talk to a PATA harddrive using ATAPI. Note that ATAPI
is a _command set_ run over IDE/ATA, *not* an _interface_.

> like that your ATAPI driver(ide-generic) grab the UltraSlim hard

ide-generic is - as the name suggests - not specific to ATAPI.

> drive, which doesn't support DMA operation for the UltraSlim drive.
> You can find the detail explanation and resolutions here:
> 	http://www.thinkwiki.org/wiki/Problems_with_SATA_and_Linux#DVD_drive_not_recognized

His problem is not that his DVD drive isn't being recognized, his
problem is that the device cannot be switched to DMA mode.
That said, i sadly don't have any ideas if/how this is possible. Maybe
you need to go into your kernel config, and enable IDE support for the
specific chipset (ICH6), as well as DMA support.

Daniel
-- 
I must obey the inscrutable exhortations of my soul.
	-- Calvin from "Calvin and Hobbes"