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Date: Wed, 16 Apr 2003 15:03:43 -0400 (EDT)
To: Jarkko Santala <jake@iki.fi>
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cc: freebsd-alpha@freebsd.org
Subject: Re: problem with UDMA mode on XP1000
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Jarkko Santala writes:
 > On Wed, 16 Apr 2003, Andrew Gallatin wrote:
 > 
 > >
 > > Jarkko Santala writes:
 > >  > I suppose no checking explains the performance. ;) But good to know
 > >  > anyway. Any reason why it gets enabled by default if its not safe?
 > >
 > > The ata code just enables the highest available mode by default.
 > >
 > > I'm no expert, but I don't think PIO is safe either.  I think it just
 > > stresses things so much less than DMA that its assumed to be safe. Drew
 > 
 > How about adding all this into the alpha Hardware Notes?
 > 

Its not alpha specific...

Drew