| Message ID | 4B4A8994.8030600@kernel.org |
|---|---|
| State | Not Applicable |
| Delegated to: | David Miller |
| Headers | show |
On Mon, Jan 11, 2010 at 11:14:44AM +0900, Tejun Heo wrote: > Interestingly, when SIDPR is used in ata_piix, writes to DET in > SControl sometimes get ignored leading to detection failure. Update > sata_link_resume() such that it reads back SControl after clearing DET > and retry if it's not clear. > > Signed-off-by: Tejun Heo <tj@kernel.org> > Reported-by: fengxiangjun <fengxiangjun@neusoft.com> > Reported-by: Jim Faulkner <jfaulkne@ccs.neu.edu> > Cc: stable@kernel.org > --- > Greg, although this patch should be included in -stable release in > time, I think it should receive some more testing in devel branch for > at least a couple of -rc cycles as it changes very fundamental part of > hardreset protocol. Is there a protocol for delayed inclusion into > -stable? If not, I'll try to remember and ping you back after some > time but I'm almost sure that I'm gonna forget this. :-) I'll drop this into my "todo-stable" queue, and ping you back on this in a few weeks. Sound good? thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Hello, On 01/12/2010 07:57 AM, Greg KH wrote: > On Mon, Jan 11, 2010 at 11:14:44AM +0900, Tejun Heo wrote: >> Interestingly, when SIDPR is used in ata_piix, writes to DET in >> SControl sometimes get ignored leading to detection failure. Update >> sata_link_resume() such that it reads back SControl after clearing DET >> and retry if it's not clear. >> >> Signed-off-by: Tejun Heo <tj@kernel.org> >> Reported-by: fengxiangjun <fengxiangjun@neusoft.com> >> Reported-by: Jim Faulkner <jfaulkne@ccs.neu.edu> >> Cc: stable@kernel.org >> --- >> Greg, although this patch should be included in -stable release in >> time, I think it should receive some more testing in devel branch for >> at least a couple of -rc cycles as it changes very fundamental part of >> hardreset protocol. Is there a protocol for delayed inclusion into >> -stable? If not, I'll try to remember and ping you back after some >> time but I'm almost sure that I'm gonna forget this. :-) > > I'll drop this into my "todo-stable" queue, and ping you back on this in > a few weeks. Sound good? Yeap, sounds good. Thanks.
On 01/10/2010 09:14 PM, Tejun Heo wrote: > Interestingly, when SIDPR is used in ata_piix, writes to DET in > SControl sometimes get ignored leading to detection failure. Update > sata_link_resume() such that it reads back SControl after clearing DET > and retry if it's not clear. > > Signed-off-by: Tejun Heo<tj@kernel.org> > Reported-by: fengxiangjun<fengxiangjun@neusoft.com> > Reported-by: Jim Faulkner<jfaulkne@ccs.neu.edu> > Cc: stable@kernel.org > --- > Greg, although this patch should be included in -stable release in > time, I think it should receive some more testing in devel branch for > at least a couple of -rc cycles as it changes very fundamental part of > hardreset protocol. Is there a protocol for delayed inclusion into > -stable? If not, I'll try to remember and ping you back after some > time but I'm almost sure that I'm gonna forget this. :-) > > Thanks. > > drivers/ata/libata-core.c | 38 +++++++++++++++++++++++++++++++------- > include/linux/libata.h | 3 +++ > 2 files changed, 34 insertions(+), 7 deletions(-) applied -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 22ff51b..6728328 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -3790,21 +3790,45 @@ int sata_link_debounce(struct ata_link *link, const unsigned long *params, int sata_link_resume(struct ata_link *link, const unsigned long *params, unsigned long deadline) { + int tries = ATA_LINK_RESUME_TRIES; u32 scontrol, serror; int rc; if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol))) return rc; - scontrol = (scontrol & 0x0f0) | 0x300; + /* + * Writes to SControl sometimes get ignored under certain + * controllers (ata_piix SIDPR). Make sure DET actually is + * cleared. + */ + do { + scontrol = (scontrol & 0x0f0) | 0x300; + if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol))) + return rc; + /* + * Some PHYs react badly if SStatus is pounded + * immediately after resuming. Delay 200ms before + * debouncing. + */ + msleep(200); - if ((rc = sata_scr_write(link, SCR_CONTROL, scontrol))) - return rc; + /* is SControl restored correctly? */ + if ((rc = sata_scr_read(link, SCR_CONTROL, &scontrol))) + return rc; + } while ((scontrol & 0xf0f) != 0x300 && --tries); - /* Some PHYs react badly if SStatus is pounded immediately - * after resuming. Delay 200ms before debouncing. - */ - msleep(200); + if ((scontrol & 0xf0f) != 0x300) { + ata_link_printk(link, KERN_ERR, + "failed to resume link (SControl %X)\n", + scontrol); + return 0; + } + + if (tries < ATA_LINK_RESUME_TRIES) + ata_link_printk(link, KERN_WARNING, + "link resume succeeded after %d retries\n", + ATA_LINK_RESUME_TRIES - tries); if ((rc = sata_link_debounce(link, params, deadline))) return rc; diff --git a/include/linux/libata.h b/include/linux/libata.h index 6a9c4dd..7311225 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -354,6 +354,9 @@ enum { /* max tries if error condition is still set after ->error_handler */ ATA_EH_MAX_TRIES = 5, + /* sometimes resuming a link requires several retries */ + ATA_LINK_RESUME_TRIES = 5, + /* how hard are we gonna try to probe/recover devices */ ATA_PROBE_MAX_TRIES = 3, ATA_EH_DEV_TRIES = 3,
Interestingly, when SIDPR is used in ata_piix, writes to DET in SControl sometimes get ignored leading to detection failure. Update sata_link_resume() such that it reads back SControl after clearing DET and retry if it's not clear. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: fengxiangjun <fengxiangjun@neusoft.com> Reported-by: Jim Faulkner <jfaulkne@ccs.neu.edu> Cc: stable@kernel.org --- Greg, although this patch should be included in -stable release in time, I think it should receive some more testing in devel branch for at least a couple of -rc cycles as it changes very fundamental part of hardreset protocol. Is there a protocol for delayed inclusion into -stable? If not, I'll try to remember and ping you back after some time but I'm almost sure that I'm gonna forget this. :-) Thanks. drivers/ata/libata-core.c | 38 +++++++++++++++++++++++++++++++------- include/linux/libata.h | 3 +++ 2 files changed, 34 insertions(+), 7 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html