[<prev] [next>] [<thread-prev] [day] [month] [year] [list]
Message-ID: <18685.41265.560866.890756@harpo.it.uu.se>
Date: Tue, 21 Oct 2008 11:30:25 +0200
From: Mikael Pettersson <mikpe@...uu.se>
To: Tejun Heo <htejun@...il.com>
Cc: Mikael Pettersson <mikpe@...uu.se>,
Christian Mueller <Christian.Mueller@....com>,
Bruce Allen <ballen@...vity.phys.uwm.edu>,
Smartmontools Mailing List
<smartmontools-support@...ts.sourceforge.net>,
LKML <linux-kernel@...r.kernel.org>,
IDE/ATA development list <linux-ide@...r.kernel.org>
Subject: Re: [smartmontools-support] inactive SATA drives won't stay in standby
or sleep, PATA models did. (fwd)
Tejun Heo writes:
> Hello,
>
> Mikael Pettersson wrote:
> > Tejun Heo writes:
> > > Hello, Mikael.
> > > I would put this into ->hardreset itself as the controller can also
> > > get out of sync with reality during reset.
> >
> > The only thing I see going on between prereset and (hard/soft)reset
> > is an optional freeze, so I don't see why moving the pdc_reset_port()
> > into the beginning of hardreset() would make any difference.
> >
> > sata_promise currently uses the ->hardreset and ->softreset inherited
> > from ata_sff_port_ops, so it would need to override both to ensure that
> > we always do pdc_reset_port() before libata does its thing. That's why
> > I felt doing that in ->prereset would be the right solution.
>
> Hmm.. reset sequence goes on like the following.
>
> 1. prereset
> 2. hardreset, if fail, retry
> 3. follow-up softreset if requested, if fail, goto #2
> 4. postreset, if successful
>
> So, if some PHY event happens while the reset is waiting for device
> readiness and makes the controller state go out of sync with the
> drive. ->prereset() will NOT be called for the following retry.
I see. Ok, then I'll forget about ->prereset and bind ->hardreset to
code which does pdc_reset_port() before invoking sata_sff_hardreset().
Thanks for your input.
/Mikael
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists