Re: [PATCH 02/20] ata_piix: unify code for programming PIO and MWDMAtimings

[Sergei Shtylyov]

Hello.

On 21-02-2011 14:38, Sergei Shtylyov wrote:

> > > PIO mode is setup by different code, and it takes care of the IORDY
> > > setting according to the PIO rules (and it gets called). DMA mode setup should
> > > just ignore the IORDY setting as in all other sane drivers.

> > Well it can't ignore it - but if you mean just keep the bit as is then

> Yes, I mean this.

> > that sounds sensible, have to see what the docs say happens if you ever
> > set MWDMA without IORDY.

> Don't think they say anything on this matter but I can't imagine that IORDY
> matters for DMA.

   What it says is that IORDY enable bit has no effect when the fast timing 
bit is cleared. That's from ICH IDE PRM (29860004.pdf).

WBR, Sergei
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