Re: [PATCH 2.6.28-rc2] sata_promise: add ATA engine reset to reset ops

[Jeff Garzik <jgarzik@pobox.com>]

Mikael Pettersson wrote:
> Promise ATA engines need to be reset when errors occur.
> That's currently done for errors detected by sata_promise itself,
> but it's not done for errors like timeouts detected outside of
> the low-level driver.
> 
> The effect of this omission is that a timeout tends to result
> in a sequence of failed COMRESETs after which libata EH gives
> up and disables the port. At that point the port's ATA engine
> hangs and even reloading the driver will not resume it.
> 
> To fix this, make sata_promise override ->hardreset on SATA
> ports with code which calls pdc_reset_port() on the port in
> question before calling libata's hardreset. PATA ports don't
> use ->hardreset, so for those we override ->softreset instead.
> 
> Signed-off-by: Mikael Pettersson <mikpe@it.uu.se>
> ---
> Updated to add pdc_reset_port() to ->softreset not ->hardreset
> on PATA ports. Patch title adjusted accordingly.
> 
> This should also go into the 2.6.27 and 2.6.26 stable branches.
> In older branches libata EH is different and I'm seeing different
> behaviour on timeouts, so I don't think this should go in as-is
> in 2.6.25 and older.
> 
>  drivers/ata/sata_promise.c |   20 ++++++++++++++++++++
>  1 file changed, 20 insertions(+)

applied