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Subject: Re: Linux 2.4.21-pre3-ac4
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Alan Cox <alan@redhat.com>
Cc: Ross Biro <rossb@google.com>, Alan Cox <alan@lxorguk.ukuu.org.uk>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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Date: 14 Jan 2003 18:38:13 +0100
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On Mon, 2003-01-13 at 20:46, Alan Cox wrote:
> > host shall wait 400 ns before reading the Status register. When entering 
> > this state from the HPIOI2 state, the host shall wait one PIO transfer 
> > cycle time before reading the Status register. The wait may be 
> > accomplished by reading the Alternate Status register and ignoring the 
> > result.
> 
> Fatal on PIIX PIO

Ok, but PIIX runs on intel platforms with real IOs, so there is no need
to perform a read... If we go the hwif->IOSYNC() way, we might well set
it up to no-op on x86 PIO iops by default and read of alt-status on
other archs if it's safe enough on other controllers/drives...

Ben.