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Subject: Re: problem with UDMA mode on XP1000
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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