Re: [PATCH 1/3] Make the IDE DMA timeout modifiable

[Sergei Shtylyov]

Mark Lord wrote:

> > > I've lost the original question from this thread, but the idea of the 

> >    The original question concerned specifically the DMA command 
> > timeout which is twice more than the usual one, WAIT_CMD (10 seconds).

> > > longish
> > > timeouts was that drive *may* be spun down ("standby"), and thus have 
> > > to spin
> > > up again to complete media commands.  Back then, drives were much 
> > > slower at
> > > spinning up than nowadays, and the ATA spec says to allow up to 30 
> > > seconds.

> >    Well, that doesn't explain the DMA case.

> When a drive is in standby, we don't send it anything special to wake up.
> So even DMA commands have to have a long enough timeout to allow
> for spinning up.

   Yes, but why *twice* as long as the others?

> Cheers

MBR, Sergei
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