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author | Gabriele Mazzotta <gabriele.mzt@gmail.com> | 2015-04-25 19:52:37 +0200 |
---|---|---|
committer | Sasha Levin <sasha.levin@oracle.com> | 2015-06-10 13:42:26 -0400 |
commit | 748e016cf59aef21d02d1ba7ff2a337d616c83c7 (patch) | |
tree | 7741ad5ea39f4f603f86a38756ecc3dab67631ab | |
parent | f62eb4c05075de5353c7bb1d1ea6c795a24abe51 (diff) | |
download | lwn-748e016cf59aef21d02d1ba7ff2a337d616c83c7.tar.gz lwn-748e016cf59aef21d02d1ba7ff2a337d616c83c7.zip |
libata: Ignore spurious PHY event on LPM policy change
[ Upstream commit 09c5b4803a80a5451d950d6a539d2eb311dc0fb1 ]
When the LPM policy is set to ATA_LPM_MAX_POWER, the device might
generate a spurious PHY event that cuases errors on the link.
Ignore this event if it occured within 10s after the policy change.
The timeout was chosen observing that on a Dell XPS13 9333 these
spurious events can occur up to roughly 6s after the policy change.
Link: http://lkml.kernel.org/g/3352987.ugV1Ipy7Z5@xps13
Signed-off-by: Gabriele Mazzotta <gabriele.mzt@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
-rw-r--r-- | drivers/ata/libata-core.c | 15 | ||||
-rw-r--r-- | drivers/ata/libata-eh.c | 3 | ||||
-rw-r--r-- | include/linux/libata.h | 9 |
3 files changed, 26 insertions, 1 deletions
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index 6a73f6b99be0..64af3bf2b4c7 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -6761,8 +6761,21 @@ u32 ata_wait_register(struct ata_port *ap, void __iomem *reg, u32 mask, u32 val, */ bool sata_lpm_ignore_phy_events(struct ata_link *link) { + unsigned long lpm_timeout = link->last_lpm_change + + msecs_to_jiffies(ATA_TMOUT_SPURIOUS_PHY); + /* if LPM is enabled, PHYRDY doesn't mean anything */ - return !!(link->lpm_policy > ATA_LPM_MAX_POWER); + if (link->lpm_policy > ATA_LPM_MAX_POWER) + return true; + + /* ignore the first PHY event after the LPM policy changed + * as it is might be spurious + */ + if ((link->flags & ATA_LFLAG_CHANGED) && + time_before(jiffies, lpm_timeout)) + return true; + + return false; } EXPORT_SYMBOL_GPL(sata_lpm_ignore_phy_events); diff --git a/drivers/ata/libata-eh.c b/drivers/ata/libata-eh.c index dad83df555c4..4ec95b76f6a1 100644 --- a/drivers/ata/libata-eh.c +++ b/drivers/ata/libata-eh.c @@ -3490,6 +3490,9 @@ static int ata_eh_set_lpm(struct ata_link *link, enum ata_lpm_policy policy, } } + link->last_lpm_change = jiffies; + link->flags |= ATA_LFLAG_CHANGED; + return 0; fail: diff --git a/include/linux/libata.h b/include/linux/libata.h index cc1d458a0595..b3a816f4c0c4 100644 --- a/include/linux/libata.h +++ b/include/linux/libata.h @@ -204,6 +204,7 @@ enum { ATA_LFLAG_SW_ACTIVITY = (1 << 7), /* keep activity stats */ ATA_LFLAG_NO_LPM = (1 << 8), /* disable LPM on this link */ ATA_LFLAG_RST_ONCE = (1 << 9), /* limit recovery to one reset */ + ATA_LFLAG_CHANGED = (1 << 10), /* LPM state changed on this link */ /* struct ata_port flags */ ATA_FLAG_SLAVE_POSS = (1 << 0), /* host supports slave dev */ @@ -308,6 +309,12 @@ enum { */ ATA_TMOUT_PMP_SRST_WAIT = 5000, + /* When the LPM policy is set to ATA_LPM_MAX_POWER, there might + * be a spurious PHY event, so ignore the first PHY event that + * occurs within 10s after the policy change. + */ + ATA_TMOUT_SPURIOUS_PHY = 10000, + /* ATA bus states */ BUS_UNKNOWN = 0, BUS_DMA = 1, @@ -786,6 +793,8 @@ struct ata_link { struct ata_eh_context eh_context; struct ata_device device[ATA_MAX_DEVICES]; + + unsigned long last_lpm_change; /* when last LPM change happened */ }; #define ATA_LINK_CLEAR_BEGIN offsetof(struct ata_link, active_tag) #define ATA_LINK_CLEAR_END offsetof(struct ata_link, device[0]) |