Re: [PATCH 02/20] ata_piix: unify code for programming PIO andMWDMA timings

[Alan Cox]

On Mon, 21 Feb 2011 14:38:37 +0300
Sergei Shtylyov <sshtylyov@xxxxxxxxxx> wrote:

> Hello.
> 
> On 21-02-2011 0:07, Alan Cox 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.

Sure - but it does matter for an ATAPI transaction with then has a DMA
phase because those timings will be used for the command transfer which
is PIO.

Alan
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