Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932819AbbGSTLs (ORCPT ); Sun, 19 Jul 2015 15:11:48 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:38667 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932698AbbGSTLn (ORCPT ); Sun, 19 Jul 2015 15:11:43 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Gabriele Mazzotta , Alexander Usyskin , Tomas Winkler Subject: [PATCH 4.0 25/58] mei: me: wait for power gating exit confirmation Date: Sun, 19 Jul 2015 12:11:03 -0700 Message-Id: <20150719190812.158312966@linuxfoundation.org> X-Mailer: git-send-email 2.4.6 In-Reply-To: <20150719190811.308546345@linuxfoundation.org> References: <20150719190811.308546345@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 7426 Lines: 238 4.0-stable review patch. If anyone has any objections, please let me know. ------------------ From: Alexander Usyskin commit 3dc196eae1db548f05e53e5875ff87b8ff79f249 upstream. Fix the hbm power gating state machine so it will wait till it receives confirmation interrupt for the PG_ISOLATION_EXIT message. In process of the suspend flow the devices first have to exit from the power gating state (runtime pm resume). If we do not handle the confirmation interrupt after sending PG_ISOLATION_EXIT message, we may receive it already after the suspend flow has changed the device state and interrupt will be interpreted as a spurious event, consequently link reset will be invoked which will prevent the device from completing the suspend flow kernel: [6603] mei_reset:136: mei_me 0000:00:16.0: powering down: end of reset kernel: [476] mei_me_irq_thread_handler:643: mei_me 0000:00:16.0: function called after ISR to handle the interrupt processing. kernel: mei_me 0000:00:16.0: FW not ready: resetting Cc: Gabriele Mazzotta Link: https://bugzilla.kernel.org/show_bug.cgi?id=86241 Link: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=770397 Tested-by: Gabriele Mazzotta Signed-off-by: Alexander Usyskin Signed-off-by: Tomas Winkler Signed-off-by: Greg Kroah-Hartman --- drivers/misc/mei/client.c | 2 - drivers/misc/mei/hw-me.c | 59 +++++++++++++++++++++++++++++++++++++++++---- drivers/misc/mei/hw-txe.c | 13 +++++++++ drivers/misc/mei/mei_dev.h | 11 ++++++++ 4 files changed, 80 insertions(+), 5 deletions(-) --- a/drivers/misc/mei/client.c +++ b/drivers/misc/mei/client.c @@ -573,7 +573,7 @@ void mei_host_client_init(struct work_st bool mei_hbuf_acquire(struct mei_device *dev) { if (mei_pg_state(dev) == MEI_PG_ON || - dev->pg_event == MEI_PG_EVENT_WAIT) { + mei_pg_in_transition(dev)) { dev_dbg(dev->dev, "device is in pg\n"); return false; } --- a/drivers/misc/mei/hw-me.c +++ b/drivers/misc/mei/hw-me.c @@ -629,11 +629,27 @@ int mei_me_pg_unset_sync(struct mei_devi mutex_lock(&dev->device_lock); reply: - if (dev->pg_event == MEI_PG_EVENT_RECEIVED) - ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_EXIT_RES_CMD); + if (dev->pg_event != MEI_PG_EVENT_RECEIVED) { + ret = -ETIME; + goto out; + } + + dev->pg_event = MEI_PG_EVENT_INTR_WAIT; + ret = mei_hbm_pg(dev, MEI_PG_ISOLATION_EXIT_RES_CMD); + if (ret) + return ret; + + mutex_unlock(&dev->device_lock); + wait_event_timeout(dev->wait_pg, + dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED, timeout); + mutex_lock(&dev->device_lock); + + if (dev->pg_event == MEI_PG_EVENT_INTR_RECEIVED) + ret = 0; else ret = -ETIME; +out: dev->pg_event = MEI_PG_EVENT_IDLE; hw->pg_state = MEI_PG_OFF; @@ -641,6 +657,19 @@ reply: } /** + * mei_me_pg_in_transition - is device now in pg transition + * + * @dev: the device structure + * + * Return: true if in pg transition, false otherwise + */ +static bool mei_me_pg_in_transition(struct mei_device *dev) +{ + return dev->pg_event >= MEI_PG_EVENT_WAIT && + dev->pg_event <= MEI_PG_EVENT_INTR_WAIT; +} + +/** * mei_me_pg_is_enabled - detect if PG is supported by HW * * @dev: the device structure @@ -672,6 +701,24 @@ notsupported: } /** + * mei_me_pg_intr - perform pg processing in interrupt thread handler + * + * @dev: the device structure + */ +static void mei_me_pg_intr(struct mei_device *dev) +{ + struct mei_me_hw *hw = to_me_hw(dev); + + if (dev->pg_event != MEI_PG_EVENT_INTR_WAIT) + return; + + dev->pg_event = MEI_PG_EVENT_INTR_RECEIVED; + hw->pg_state = MEI_PG_OFF; + if (waitqueue_active(&dev->wait_pg)) + wake_up(&dev->wait_pg); +} + +/** * mei_me_irq_quick_handler - The ISR of the MEI device * * @irq: The irq number @@ -729,6 +776,8 @@ irqreturn_t mei_me_irq_thread_handler(in goto end; } + mei_me_pg_intr(dev); + /* check if we need to start the dev */ if (!mei_host_is_ready(dev)) { if (mei_hw_is_ready(dev)) { @@ -765,9 +814,10 @@ irqreturn_t mei_me_irq_thread_handler(in /* * During PG handshake only allowed write is the replay to the * PG exit message, so block calling write function - * if the pg state is not idle + * if the pg event is in PG handshake */ - if (dev->pg_event == MEI_PG_EVENT_IDLE) { + if (dev->pg_event != MEI_PG_EVENT_WAIT && + dev->pg_event != MEI_PG_EVENT_RECEIVED) { rets = mei_irq_write_handler(dev, &complete_list); dev->hbuf_is_ready = mei_hbuf_is_ready(dev); } @@ -792,6 +842,7 @@ static const struct mei_hw_ops mei_me_hw .hw_config = mei_me_hw_config, .hw_start = mei_me_hw_start, + .pg_in_transition = mei_me_pg_in_transition, .pg_is_enabled = mei_me_pg_is_enabled, .intr_clear = mei_me_intr_clear, --- a/drivers/misc/mei/hw-txe.c +++ b/drivers/misc/mei/hw-txe.c @@ -302,6 +302,18 @@ int mei_txe_aliveness_set_sync(struct me } /** + * mei_txe_pg_in_transition - is device now in pg transition + * + * @dev: the device structure + * + * Return: true if in pg transition, false otherwise + */ +static bool mei_txe_pg_in_transition(struct mei_device *dev) +{ + return dev->pg_event == MEI_PG_EVENT_WAIT; +} + +/** * mei_txe_pg_is_enabled - detect if PG is supported by HW * * @dev: the device structure @@ -1138,6 +1150,7 @@ static const struct mei_hw_ops mei_txe_h .hw_config = mei_txe_hw_config, .hw_start = mei_txe_hw_start, + .pg_in_transition = mei_txe_pg_in_transition, .pg_is_enabled = mei_txe_pg_is_enabled, .intr_clear = mei_txe_intr_clear, --- a/drivers/misc/mei/mei_dev.h +++ b/drivers/misc/mei/mei_dev.h @@ -269,6 +269,7 @@ struct mei_cl { * @fw_status : get fw status registers * @pg_state : power gating state of the device + * @pg_in_transition : is device now in pg transition * @pg_is_enabled : is power gating enabled * @intr_clear : clear pending interrupts @@ -298,6 +299,7 @@ struct mei_hw_ops { int (*fw_status)(struct mei_device *dev, struct mei_fw_status *fw_sts); enum mei_pg_state (*pg_state)(struct mei_device *dev); + bool (*pg_in_transition)(struct mei_device *dev); bool (*pg_is_enabled)(struct mei_device *dev); void (*intr_clear)(struct mei_device *dev); @@ -396,11 +398,15 @@ struct mei_cl_device { * @MEI_PG_EVENT_IDLE: the driver is not in power gating transition * @MEI_PG_EVENT_WAIT: the driver is waiting for a pg event to complete * @MEI_PG_EVENT_RECEIVED: the driver received pg event + * @MEI_PG_EVENT_INTR_WAIT: the driver is waiting for a pg event interrupt + * @MEI_PG_EVENT_INTR_RECEIVED: the driver received pg event interrupt */ enum mei_pg_event { MEI_PG_EVENT_IDLE, MEI_PG_EVENT_WAIT, MEI_PG_EVENT_RECEIVED, + MEI_PG_EVENT_INTR_WAIT, + MEI_PG_EVENT_INTR_RECEIVED, }; /** @@ -727,6 +733,11 @@ static inline enum mei_pg_state mei_pg_s return dev->ops->pg_state(dev); } +static inline bool mei_pg_in_transition(struct mei_device *dev) +{ + return dev->ops->pg_in_transition(dev); +} + static inline bool mei_pg_is_enabled(struct mei_device *dev) { return dev->ops->pg_is_enabled(dev); -- 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/