Re: (es)ata drives may need an explicit spinup command?

On Thu, Aug 06, 2009 at 04:30:49PM -0500, Rick C. Petty wrote:
> On Thu, Aug 06, 2009 at 10:56:44PM +0300, Alexander Motin wrote:
> > Juergen Lock wrote:
> > >So I tested esata on a siis pcie card with a 750G Seagate Freeagent Pro
> > >drive and it does work - until the drive falls into powersave mode
> > >after being idle for a little while. :(  (I had the drive on 1394
> > >before on another box where it was able to recover from this condition,
> > >but not on usb or esata - and the drive's 1394 interface died a while
> > >ago and also esata is faster anyway...)
> > >
> > > And now I came across this patch for the linux ata driver:
> > >	http://git.kernel.org/?p=linux/kernel/git/jgarzik/libata-dev.git;a=commitdiff;h=169439c2e35f01e7832a9b4fc8a7446980c3d593;hp=1e999736cafdffc374f22eed37b291129ef82e4e
> > >
> > > So my question is, could the same be done in our ata code?
> > >I have a slight :) hope it would help this drive too at least as it
> > >does seem to work on Linux...
> > 
> > I am not sure it is related to your case, as you said your drive works 
> > for some time after plug. If drive spun-down automatically due to 
> > inactivity, it should spin-up automatically also, as OS unable to track 
> > that transition. 30 seconds of ATA command timeout should be sufficient 
> > for drive to do this. Do you have any other symptoms?
> 
> I believe this patch is for something different.  Certain drives are
> automatically spun down at power up.  One such drive is in my satellite
> provider's DVR.  If you hook it up to regular SATA and power, it will never
> spin up.  It requires a special ATA command to tell it to spin up.  I
> believe the linux patch does precisely this.  I know there's a special
> SATA power cable that tells the drive not to spin up until given the spinup
> command, which I also found in my satellite provider's DVR.  Basically this
> is done through pin 11:
> 	http://en.wikipedia.org/wiki/Serial_ATA#Power_supply
> 
> Although not every drive supports this feature.

Yup it does seem to be something different after all as the new siis(4)
driver handles the condition just fine, apparently I only tested the
drive on the old ata driver.

 Oh well...
	Juergen