From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alan <alan@lxorguk.ukuu.org.uk>
Subject: Re: Nvidia cable detection problems (was [PATCH] amd74xx: don't
 configure udma mode higher than BIOS did)
Date: Mon, 5 Feb 2007 18:12:24 +0000
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To: Allen Martin <AMartin@nvidia.com>
Cc: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>, linux-ide@vger.kernel.org, linux-kernel <linux-kernel@vger.kernel.org>

> The *real* solution is to use the BIOS ACPI _GTM _STM methods for this.
> Then you can remove all chipset specific knowledge from the IDE driver.
> This is what the MS driver does on Windows, so you know it's received a
> lot of testing from NVIDIA and board vendors.

Well we can certainly do some of that if ACPI is present and active. In
particular since _GTM will give us current modes allowing for hotplug and
post BIOS boot kexec etc it ought to be safe to do Tejun's hack that way.
We could even probe UDMA3+ capable devices by doing _STM to a high mode
and _GTM to determine the cable type 8)

Alan