Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1424017AbbFEOqV (ORCPT ); Fri, 5 Jun 2015 10:46:21 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:59469 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754566AbbFEN6r (ORCPT ); Fri, 5 Jun 2015 09:58:47 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Gabriele Mazzotta , Tejun Heo , Luis Henriques Subject: [PATCH 3.16.y-ckt 009/110] libata: Ignore spurious PHY event on LPM policy change Date: Fri, 5 Jun 2015 14:56:52 +0100 Message-Id: <1433512713-22984-10-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1433512713-22984-1-git-send-email-luis.henriques@canonical.com> References: <1433512713-22984-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 3667 Lines: 105 3.16.7-ckt13 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Gabriele Mazzotta commit 09c5b4803a80a5451d950d6a539d2eb311dc0fb1 upstream. 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 Signed-off-by: Tejun Heo Signed-off-by: Luis Henriques --- drivers/ata/libata-core.c | 15 ++++++++++++++- drivers/ata/libata-eh.c | 3 +++ include/linux/libata.h | 9 +++++++++ 3 files changed, 26 insertions(+), 1 deletion(-) diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c index c89f10fbf169..52ddc0afcaf6 100644 --- a/drivers/ata/libata-core.c +++ b/drivers/ata/libata-core.c @@ -6827,8 +6827,21 @@ 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 6461f30ae5bf..91aac2525c09 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]) -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/