Re: [PATCH #upstream] libata: use longer 0xff wait if parallel scan is enabled

[Jeff Garzik <jeff@garzik.org>]

On 04/09/2010 06:46 AM, Tejun Heo wrote:
> There are some SATA devices which take relatively long to get out of
> 0xff status after reset.  In libata, this timeout is determined by
> ATA_TMOUT_FF_WAIT.  Quantum GoVault is the worst requring about 2s for
> reliable detection.  However, because 2s 0xff timeout can introduce
> rather long spurious delay during boot, libata has been compromising
> at the next longest timeout of 800ms for HHD424020F7SV00 iVDR drive.
>
> Now that parallel scan is in place for common drivers, libata can
> afford 2s 0xff timeout.  Use 2s 0xff timeout if parallel scan is
> enabled.
>
> Please note that the chance of spurious wait is pretty slim w/ working
> SCR access so this will only affect SATA controllers w/o SCR access
> which isn't too common these days.
>
> Please read the following thread for more information on the GoVault
> drive.
>
>    http://thread.gmane.org/gmane.linux.ide/14545/focus=14663
>
> Signed-off-by: Tejun Heo<tj@kernel.org>
> Cc: Gary Hade<garyhade@us.ibm.com>
> ---
>   drivers/ata/libata-core.c |   18 ++++++++++++------
>   include/linux/libata.h    |   11 ++++++-----
>   2 files changed, 18 insertions(+), 11 deletions(-)

applied