11 files changed, 167 insertions, 0 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-1000.c b/drivers/net/wireless/iwlwifi/iwl-1000.c
index e31e8a3459b..5a9cb70160f 100644
--- a/drivers/net/wireless/iwlwifi/iwl-1000.c
+++ b/drivers/net/wireless/iwlwifi/iwl-1000.c
@@ -212,6 +212,7 @@ static struct iwl_lib_ops iwl1000_lib = {
                 .set_ct_kill = iwl1000_set_ct_threshold,
          },
         .add_bcast_station = iwl_add_bcast_station,
+        .recover_from_tx_stall = iwl_bg_monitor_recover,
 };
 
 static const struct iwl_ops iwl1000_ops = {
@@ -249,6 +250,7 @@ struct iwl_cfg iwl1000_bgn_cfg = {
         .support_ct_kill_exit = true,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_EXT_LONG_THRESHOLD_DEF,
         .chain_noise_scale = 1000,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 struct iwl_cfg iwl1000_bg_cfg = {
@@ -277,6 +279,7 @@ struct iwl_cfg iwl1000_bg_cfg = {
         .support_ct_kill_exit = true,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_EXT_LONG_THRESHOLD_DEF,
         .chain_noise_scale = 1000,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 MODULE_FIRMWARE(IWL1000_MODULE_FIRMWARE(IWL1000_UCODE_API_MAX));
diff --git a/drivers/net/wireless/iwlwifi/iwl-3945.c b/drivers/net/wireless/iwlwifi/iwl-3945.c
index 11785e2c767..21ae61dd3d5 100644
--- a/drivers/net/wireless/iwlwifi/iwl-3945.c
+++ b/drivers/net/wireless/iwlwifi/iwl-3945.c
@@ -2820,6 +2820,7 @@ static struct iwl_cfg iwl3945_bg_cfg = {
         .led_compensation = 64,
         .broken_powersave = true,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_THRESHOLD_DEF,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 static struct iwl_cfg iwl3945_abg_cfg = {
@@ -2838,6 +2839,7 @@ static struct iwl_cfg iwl3945_abg_cfg = {
         .led_compensation = 64,
         .broken_powersave = true,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_THRESHOLD_DEF,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 DEFINE_PCI_DEVICE_TABLE(iwl3945_hw_card_ids) = {
diff --git a/drivers/net/wireless/iwlwifi/iwl-4965.c b/drivers/net/wireless/iwlwifi/iwl-4965.c
index 7f9e448fe5e..acca89a635a 100644
--- a/drivers/net/wireless/iwlwifi/iwl-4965.c
+++ b/drivers/net/wireless/iwlwifi/iwl-4965.c
@@ -2255,6 +2255,7 @@ struct iwl_cfg iwl4965_agn_cfg = {
         .led_compensation = 61,
         .chain_noise_num_beacons = IWL4965_CAL_NUM_BEACONS,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_THRESHOLD_DEF,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 /* Module firmware */
diff --git a/drivers/net/wireless/iwlwifi/iwl-5000.c b/drivers/net/wireless/iwlwifi/iwl-5000.c
index 8ab28a76015..a01b3c59a5a 100644
--- a/drivers/net/wireless/iwlwifi/iwl-5000.c
+++ b/drivers/net/wireless/iwlwifi/iwl-5000.c
@@ -1499,6 +1499,7 @@ struct iwl_lib_ops iwl5000_lib = {
                 .set_ct_kill = iwl5000_set_ct_threshold,
          },
         .add_bcast_station = iwl_add_bcast_station,
+        .recover_from_tx_stall = iwl_bg_monitor_recover,
 };
 
 static struct iwl_lib_ops iwl5150_lib = {
@@ -1553,6 +1554,7 @@ static struct iwl_lib_ops iwl5150_lib = {
                 .set_ct_kill = iwl5150_set_ct_threshold,
          },
         .add_bcast_station = iwl_add_bcast_station,
+        .recover_from_tx_stall = iwl_bg_monitor_recover,
 };
 
 static const struct iwl_ops iwl5000_ops = {
@@ -1602,6 +1604,7 @@ struct iwl_cfg iwl5300_agn_cfg = {
         .chain_noise_num_beacons = IWL_CAL_NUM_BEACONS,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_LONG_THRESHOLD_DEF,
         .chain_noise_scale = 1000,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 struct iwl_cfg iwl5100_bgn_cfg = {
@@ -1628,6 +1631,7 @@ struct iwl_cfg iwl5100_bgn_cfg = {
         .chain_noise_num_beacons = IWL_CAL_NUM_BEACONS,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_LONG_THRESHOLD_DEF,
         .chain_noise_scale = 1000,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 struct iwl_cfg iwl5100_abg_cfg = {
@@ -1652,6 +1656,7 @@ struct iwl_cfg iwl5100_abg_cfg = {
         .chain_noise_num_beacons = IWL_CAL_NUM_BEACONS,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_LONG_THRESHOLD_DEF,
         .chain_noise_scale = 1000,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 struct iwl_cfg iwl5100_agn_cfg = {
@@ -1678,6 +1683,7 @@ struct iwl_cfg iwl5100_agn_cfg = {
         .chain_noise_num_beacons = IWL_CAL_NUM_BEACONS,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_LONG_THRESHOLD_DEF,
         .chain_noise_scale = 1000,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 struct iwl_cfg iwl5350_agn_cfg = {
@@ -1704,6 +1710,7 @@ struct iwl_cfg iwl5350_agn_cfg = {
         .chain_noise_num_beacons = IWL_CAL_NUM_BEACONS,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_LONG_THRESHOLD_DEF,
         .chain_noise_scale = 1000,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 struct iwl_cfg iwl5150_agn_cfg = {
@@ -1730,6 +1737,7 @@ struct iwl_cfg iwl5150_agn_cfg = {
         .chain_noise_num_beacons = IWL_CAL_NUM_BEACONS,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_LONG_THRESHOLD_DEF,
         .chain_noise_scale = 1000,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 struct iwl_cfg iwl5150_abg_cfg = {
@@ -1754,6 +1762,7 @@ struct iwl_cfg iwl5150_abg_cfg = {
         .chain_noise_num_beacons = IWL_CAL_NUM_BEACONS,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_LONG_THRESHOLD_DEF,
         .chain_noise_scale = 1000,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 MODULE_FIRMWARE(IWL5000_MODULE_FIRMWARE(IWL5000_UCODE_API_MAX));
diff --git a/drivers/net/wireless/iwlwifi/iwl-6000.c b/drivers/net/wireless/iwlwifi/iwl-6000.c
index fb7012289c3..4fbc38cfd91 100644
--- a/drivers/net/wireless/iwlwifi/iwl-6000.c
+++ b/drivers/net/wireless/iwlwifi/iwl-6000.c
@@ -278,6 +278,7 @@ static struct iwl_lib_ops iwl6000_lib = {
                 .set_ct_kill = iwl6000_set_ct_threshold,
          },
         .add_bcast_station = iwl_add_bcast_station,
+        .recover_from_tx_stall = iwl_bg_monitor_recover,
 };
 
 static const struct iwl_ops iwl6000_ops = {
@@ -343,6 +344,7 @@ static struct iwl_lib_ops iwl6050_lib = {
                 .set_calib_version = iwl6050_set_calib_version,
          },
         .add_bcast_station = iwl_add_bcast_station,
+        .recover_from_tx_stall = iwl_bg_monitor_recover,
 };
 
 static const struct iwl_ops iwl6050_ops = {
@@ -386,6 +388,7 @@ struct iwl_cfg iwl6000i_2agn_cfg = {
         .support_ct_kill_exit = true,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_THRESHOLD_DEF,
         .chain_noise_scale = 1000,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 struct iwl_cfg iwl6000i_2abg_cfg = {
@@ -417,6 +420,7 @@ struct iwl_cfg iwl6000i_2abg_cfg = {
         .support_ct_kill_exit = true,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_THRESHOLD_DEF,
         .chain_noise_scale = 1000,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 struct iwl_cfg iwl6000i_2bg_cfg = {
@@ -448,6 +452,7 @@ struct iwl_cfg iwl6000i_2bg_cfg = {
         .support_ct_kill_exit = true,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_THRESHOLD_DEF,
         .chain_noise_scale = 1000,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 struct iwl_cfg iwl6050_2agn_cfg = {
@@ -480,6 +485,7 @@ struct iwl_cfg iwl6050_2agn_cfg = {
         .support_ct_kill_exit = true,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_THRESHOLD_DEF,
         .chain_noise_scale = 1500,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 struct iwl_cfg iwl6050_2abg_cfg = {
@@ -511,6 +517,7 @@ struct iwl_cfg iwl6050_2abg_cfg = {
         .support_ct_kill_exit = true,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_THRESHOLD_DEF,
         .chain_noise_scale = 1500,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 struct iwl_cfg iwl6000_3agn_cfg = {
@@ -543,6 +550,7 @@ struct iwl_cfg iwl6000_3agn_cfg = {
         .support_ct_kill_exit = true,
         .plcp_delta_threshold = IWL_MAX_PLCP_ERR_THRESHOLD_DEF,
         .chain_noise_scale = 1000,
+        .monitor_recover_period = IWL_MONITORING_PERIOD,
 };
 
 MODULE_FIRMWARE(IWL6000_MODULE_FIRMWARE(IWL6000_UCODE_API_MAX));
diff --git a/drivers/net/wireless/iwlwifi/iwl-agn.c b/drivers/net/wireless/iwlwifi/iwl-agn.c
index 93931b61304..82b1a3fb54e 100644
--- a/drivers/net/wireless/iwlwifi/iwl-agn.c
+++ b/drivers/net/wireless/iwlwifi/iwl-agn.c
@@ -2074,6 +2074,13 @@ static void iwl_alive_start(struct iwl_priv *priv)
         /* After the ALIVE response, we can send host commands to the uCode */
         set_bit(STATUS_ALIVE, &priv->status);
 
+        if (priv->cfg->ops->lib->recover_from_tx_stall) {
+                /* Enable timer to monitor the driver queues */
+                mod_timer(&priv->monitor_recover,
+                        jiffies +
+                        msecs_to_jiffies(priv->cfg->monitor_recover_period));
+        }
+
         if (iwl_is_rfkill(priv))
                 return;
 
@@ -3224,6 +3231,13 @@ static void iwl_setup_deferred_work(struct iwl_priv *priv)
         priv->ucode_trace.data = (unsigned long)priv;
         priv->ucode_trace.function = iwl_bg_ucode_trace;
 
+        if (priv->cfg->ops->lib->recover_from_tx_stall) {
+                init_timer(&priv->monitor_recover);
+                priv->monitor_recover.data = (unsigned long)priv;
+                priv->monitor_recover.function =
+                        priv->cfg->ops->lib->recover_from_tx_stall;
+        }
+
         if (!priv->cfg->use_isr_legacy)
                 tasklet_init(&priv->irq_tasklet, (void (*)(unsigned long))
                         iwl_irq_tasklet, (unsigned long)priv);
@@ -3243,6 +3257,8 @@ static void iwl_cancel_deferred_work(struct iwl_priv *priv)
         cancel_work_sync(&priv->beacon_update);
         del_timer_sync(&priv->statistics_periodic);
         del_timer_sync(&priv->ucode_trace);
+        if (priv->cfg->ops->lib->recover_from_tx_stall)
+                del_timer_sync(&priv->monitor_recover);
 }
 
 static void iwl_init_hw_rates(struct iwl_priv *priv,
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.c b/drivers/net/wireless/iwlwifi/iwl-core.c
index d4c2a3e17c5..5180fb24cd3 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.c
+++ b/drivers/net/wireless/iwlwifi/iwl-core.c
@@ -3051,6 +3051,99 @@ int iwl_force_reset(struct iwl_priv *priv, int mode)
         }
         return 0;
 }
+EXPORT_SYMBOL(iwl_force_reset);
+
+/**
+ * iwl_bg_monitor_recover - Timer callback to check for stuck queue and recover
+ *
+ * During normal condition (no queue is stuck), the timer is continually set to
+ * execute every monitor_recover_period milliseconds after the last timer
+ * expired.  When the queue read_ptr is at the same place, the timer is
+ * shorten to 100mSecs.  This is
+ *      1) to reduce the chance that the read_ptr may wrap around (not stuck)
+ *      2) to detect the stuck queues quicker before the station and AP can
+ *      disassociate each other.
+ *
+ * This function monitors all the tx queues and recover from it if any
+ * of the queues are stuck.
+ * 1. It first check the cmd queue for stuck conditions.  If it is stuck,
+ *      it will recover by resetting the firmware and return.
+ * 2. Then, it checks for station association.  If it associates it will check
+ *      other queues.  If any queue is stuck, it will recover by resetting
+ *      the firmware.
+ * Note: It the number of times the queue read_ptr to be at the same place to
+ *      be MAX_REPEAT+1 in order to consider to be stuck.
+ */
+/*
+ * The maximum number of times the read pointer of the tx queue at the
+ * same place without considering to be stuck.
+ */
+#define MAX_REPEAT      (2)
+static int iwl_check_stuck_queue(struct iwl_priv *priv, int cnt)
+{
+        struct iwl_tx_queue *txq;
+        struct iwl_queue *q;
+
+        txq = &priv->txq[cnt];
+        q = &txq->q;
+        /* queue is empty, skip */
+        if (q->read_ptr != q->write_ptr) {
+                if (q->read_ptr == q->last_read_ptr) {
+                        /* a queue has not been read from last time */
+                        if (q->repeat_same_read_ptr > MAX_REPEAT) {
+                                IWL_ERR(priv,
+                                        "queue %d stuck %d time. Fw reload.\n",
+                                        q->id, q->repeat_same_read_ptr);
+                                q->repeat_same_read_ptr = 0;
+                                iwl_force_reset(priv, IWL_FW_RESET);
+                        } else {
+                                q->repeat_same_read_ptr++;
+                                IWL_DEBUG_RADIO(priv,
+                                                "queue %d, not read %d time\n",
+                                                q->id,
+                                                q->repeat_same_read_ptr);
+                                mod_timer(&priv->monitor_recover, jiffies +
+                                        msecs_to_jiffies(IWL_ONE_HUNDRED_MSECS));
+                        }
+                        return 1;
+                } else {
+                        q->last_read_ptr = q->read_ptr;
+                        q->repeat_same_read_ptr = 0;
+                }
+        }
+        return 0;
+}
+
+void iwl_bg_monitor_recover(unsigned long data)
+{
+        struct iwl_priv *priv = (struct iwl_priv *)data;
+        int cnt;
+
+        if (test_bit(STATUS_EXIT_PENDING, &priv->status))
+                return;
+
+        /* monitor and check for stuck cmd queue */
+        if (iwl_check_stuck_queue(priv, IWL_CMD_QUEUE_NUM))
+                return;
+
+        /* monitor and check for other stuck queues */
+        if (iwl_is_associated(priv)) {
+                for (cnt = 0; cnt < priv->hw_params.max_txq_num; cnt++) {
+                        /* skip as we already checked the command queue */
+                        if (cnt == IWL_CMD_QUEUE_NUM)
+                                continue;
+                        if (iwl_check_stuck_queue(priv, cnt))
+                                return;
+                }
+        }
+        /*
+         * Reschedule the timer to occur in
+         * priv->cfg->monitor_recover_period
+         */
+        mod_timer(&priv->monitor_recover,
+                jiffies + msecs_to_jiffies(priv->cfg->monitor_recover_period));
+}
+EXPORT_SYMBOL(iwl_bg_monitor_recover);
 
 #ifdef CONFIG_PM
 
diff --git a/drivers/net/wireless/iwlwifi/iwl-core.h b/drivers/net/wireless/iwlwifi/iwl-core.h
index 2482a25d543..c4cd1deb3b3 100644
--- a/drivers/net/wireless/iwlwifi/iwl-core.h
+++ b/drivers/net/wireless/iwlwifi/iwl-core.h
@@ -191,6 +191,8 @@ struct iwl_lib_ops {
         struct iwl_temp_ops temp_ops;
         /* station management */
         void (*add_bcast_station)(struct iwl_priv *priv);
+        /* recover from tx queue stall */
+        void (*recover_from_tx_stall)(unsigned long data);
 };
 
 struct iwl_led_ops {
@@ -295,6 +297,8 @@ struct iwl_cfg {
         const bool support_wimax_coexist;
         u8 plcp_delta_threshold;
         s32 chain_noise_scale;
+        /* timer period for monitor the driver queues */
+        u32 monitor_recover_period;
 };
 
 /***************************
@@ -568,6 +572,9 @@ static inline u16 iwl_pcie_link_ctl(struct iwl_priv *priv)
         pci_read_config_word(priv->pci_dev, pos + PCI_EXP_LNKCTL, &pci_lnk_ctl);
         return pci_lnk_ctl;
 }
+
+void iwl_bg_monitor_recover(unsigned long data);
+
 #ifdef CONFIG_PM
 int iwl_pci_suspend(struct pci_dev *pdev, pm_message_t state);
 int iwl_pci_resume(struct pci_dev *pdev);
diff --git a/drivers/net/wireless/iwlwifi/iwl-dev.h b/drivers/net/wireless/iwlwifi/iwl-dev.h
index 9c676ea420b..bb4cba508ac 100644
--- a/drivers/net/wireless/iwlwifi/iwl-dev.h
+++ b/drivers/net/wireless/iwlwifi/iwl-dev.h
@@ -183,6 +183,10 @@ struct iwl_queue {
         int n_bd;              /* number of BDs in this queue */
         int write_ptr;       /* 1-st empty entry (index) host_w*/
         int read_ptr;         /* last used entry (index) host_r*/
+        /* use for monitoring and recovering the stuck queue */
+        int last_read_ptr;      /* storing the last read_ptr */
+        /* number of time read_ptr and last_read_ptr are the same */
+        u8 repeat_same_read_ptr;
         dma_addr_t dma_addr;   /* physical addr for BD's */
         int n_window;          /* safe queue window */
         u32 id;
@@ -1044,6 +1048,11 @@ struct iwl_event_log {
 #define IWL_DELAY_NEXT_FORCE_RF_RESET  (HZ*3)
 #define IWL_DELAY_NEXT_FORCE_FW_RELOAD (HZ*5)
 
+/* timer constants use to monitor and recover stuck tx queues in mSecs */
+#define IWL_MONITORING_PERIOD  (1000)
+#define IWL_ONE_HUNDRED_MSECS   (100)
+#define IWL_SIXTY_SECS          (60000)
+
 enum iwl_reset {
         IWL_RF_RESET = 0,
         IWL_FW_RESET,
@@ -1354,6 +1363,7 @@ struct iwl_priv {
         struct work_struct run_time_calib_work;
         struct timer_list statistics_periodic;
         struct timer_list ucode_trace;
+        struct timer_list monitor_recover;
         bool hw_ready;
 
         struct iwl_event_log event_log;
diff --git a/drivers/net/wireless/iwlwifi/iwl-tx.c b/drivers/net/wireless/iwlwifi/iwl-tx.c
index 045e4a67344..34c983833a8 100644
--- a/drivers/net/wireless/iwlwifi/iwl-tx.c
+++ b/drivers/net/wireless/iwlwifi/iwl-tx.c
@@ -322,6 +322,8 @@ static int iwl_queue_init(struct iwl_priv *priv, struct iwl_queue *q,
                 q->high_mark = 2;
 
         q->write_ptr = q->read_ptr = 0;
+        q->last_read_ptr = 0;
+        q->repeat_same_read_ptr = 0;
 
         return 0;
 }
diff --git a/drivers/net/wireless/iwlwifi/iwl3945-base.c b/drivers/net/wireless/iwlwifi/iwl3945-base.c
index 6687b945655..4995134d7e4 100644
--- a/drivers/net/wireless/iwlwifi/iwl3945-base.c
+++ b/drivers/net/wireless/iwlwifi/iwl3945-base.c
@@ -2501,6 +2501,13 @@ static void iwl3945_alive_start(struct iwl_priv *priv)
         /* After the ALIVE response, we can send commands to 3945 uCode */
         set_bit(STATUS_ALIVE, &priv->status);
 
+        if (priv->cfg->ops->lib->recover_from_tx_stall) {
+                /* Enable timer to monitor the driver queues */
+                mod_timer(&priv->monitor_recover,
+                        jiffies +
+                        msecs_to_jiffies(priv->cfg->monitor_recover_period));
+        }
+
         if (iwl_is_rfkill(priv))
                 return;
 
@@ -3796,6 +3803,13 @@ static void iwl3945_setup_deferred_work(struct iwl_priv *priv)
 
         iwl3945_hw_setup_deferred_work(priv);
 
+        if (priv->cfg->ops->lib->recover_from_tx_stall) {
+                init_timer(&priv->monitor_recover);
+                priv->monitor_recover.data = (unsigned long)priv;
+                priv->monitor_recover.function =
+                        priv->cfg->ops->lib->recover_from_tx_stall;
+        }
+
         tasklet_init(&priv->irq_tasklet, (void (*)(unsigned long))
                      iwl3945_irq_tasklet, (unsigned long)priv);
 }
@@ -3808,6 +3822,8 @@ static void iwl3945_cancel_deferred_work(struct iwl_priv *priv)
         cancel_delayed_work(&priv->scan_check);
         cancel_delayed_work(&priv->alive_start);
         cancel_work_sync(&priv->beacon_update);
+        if (priv->cfg->ops->lib->recover_from_tx_stall)
+                del_timer_sync(&priv->monitor_recover);
 }
 
 static struct attribute *iwl3945_sysfs_entries[] = {