iwl3945: add plcp error checking

Add plcp error checking for 3945. After threshold of plcp
is reached , it resets the radio

Signed-off-by: Abhijeet Kolekar <abhijeet.kolekar@intel.com>
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>

diff --git a/drivers/net/wireless/iwlwifi/iwl-3945.c b/drivers/net/wireless/iwlwifi/iwl-3945.c
index a4d842a..05d808b 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-3945.c
+++ b/drivers/net/wireless/iwlwifi/iwl-3945.c
@@ -390,6 +390,67 @@ static void iwl3945_accumulative_statistics(struct iwl_priv *priv,
 }
 #endif
 
+/**
+ * iwl3945_good_plcp_health - checks for plcp error.
+ *
+ * When the plcp error is exceeding the thresholds, reset the radio
+ * to improve the throughput.
+ */
+static bool iwl3945_good_plcp_health(struct iwl_priv *priv,
+                               struct iwl_rx_packet *pkt)
+{
+       bool rc = true;
+       struct iwl3945_notif_statistics current_stat;
+       int combined_plcp_delta;
+       unsigned int plcp_msec;
+       unsigned long plcp_received_jiffies;
+
+       memcpy(&current_stat, pkt->u.raw, sizeof(struct
+                       iwl3945_notif_statistics));
+       /*
+        * check for plcp_err and trigger radio reset if it exceeds
+        * the plcp error threshold plcp_delta.
+        */
+       plcp_received_jiffies = jiffies;
+       plcp_msec = jiffies_to_msecs((long) plcp_received_jiffies -
+                                       (long) priv->plcp_jiffies);
+       priv->plcp_jiffies = plcp_received_jiffies;
+       /*
+        * check to make sure plcp_msec is not 0 to prevent division
+        * by zero.
+        */
+       if (plcp_msec) {
+               combined_plcp_delta =
+                       (le32_to_cpu(current_stat.rx.ofdm.plcp_err) -
+                       le32_to_cpu(priv->_3945.statistics.rx.ofdm.plcp_err));
+
+               if ((combined_plcp_delta > 0) &&
+                       ((combined_plcp_delta * 100) / plcp_msec) >
+                       priv->cfg->plcp_delta_threshold) {
+                       /*
+                        * if plcp_err exceed the threshold, the following
+                        * data is printed in csv format:
+                        *    Text: plcp_err exceeded %d,
+                        *    Received ofdm.plcp_err,
+                        *    Current ofdm.plcp_err,
+                        *    combined_plcp_delta,
+                        *    plcp_msec
+                        */
+                       IWL_DEBUG_RADIO(priv, "plcp_err exceeded %u, "
+                               "%u, %d, %u mSecs\n",
+                               priv->cfg->plcp_delta_threshold,
+                               le32_to_cpu(current_stat.rx.ofdm.plcp_err),
+                               combined_plcp_delta, plcp_msec);
+                       /*
+                        * Reset the RF radio due to the high plcp
+                        * error rate
+                        */
+                       rc = false;
+               }
+       }
+       return rc;
+}
+
 void iwl3945_hw_rx_statistics(struct iwl_priv *priv,
                struct iwl_rx_mem_buffer *rxb)
 {
@@ -401,6 +462,7 @@ void iwl3945_hw_rx_statistics(struct iwl_priv *priv,
 #ifdef CONFIG_IWLWIFI_DEBUG
        iwl3945_accumulative_statistics(priv, (__le32 *)&pkt->u.raw);
 #endif
+       iwl_recover_from_statistics(priv, pkt);
 
        memcpy(&priv->_3945.statistics, pkt->u.raw, sizeof(priv->_3945.statistics));
 }
@@ -2792,6 +2854,7 @@ static struct iwl_lib_ops iwl3945_lib = {
        .config_ap = iwl3945_config_ap,
        .manage_ibss_station = iwl3945_manage_ibss_station,
        .add_bcast_station = iwl3945_add_bcast_station,
+       .check_plcp_health = iwl3945_good_plcp_health,
 
        .debugfs_ops = {
                .rx_stats_read = iwl3945_ucode_rx_stats_read,
@@ -2832,7 +2895,7 @@ static struct iwl_cfg iwl3945_bg_cfg = {
        .ht_greenfield_support = false,
        .led_compensation = 64,
        .broken_powersave = true,
-       .plcp_delta_threshold = IWL_MAX_PLCP_ERR_THRESHOLD_DEF,
+       .plcp_delta_threshold = IWL_MAX_PLCP_ERR_LONG_THRESHOLD_DEF,
        .monitor_recover_period = IWL_MONITORING_PERIOD,
        .max_event_log_size = 512,
        .tx_power_by_driver = true,
@@ -2853,7 +2916,7 @@ static struct iwl_cfg iwl3945_abg_cfg = {
        .ht_greenfield_support = false,
        .led_compensation = 64,
        .broken_powersave = true,
-       .plcp_delta_threshold = IWL_MAX_PLCP_ERR_THRESHOLD_DEF,
+       .plcp_delta_threshold = IWL_MAX_PLCP_ERR_LONG_THRESHOLD_DEF,
        .monitor_recover_period = IWL_MONITORING_PERIOD,
        .max_event_log_size = 512,
        .tx_power_by_driver = true,

diff --git a/drivers/net/wireless/iwlwifi/iwl-core.h b/drivers/net/wireless/iwlwifi/iwl-core.h
index 2f664a3..7a3f949 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-core.h
+++ b/drivers/net/wireless/iwlwifi/iwl-core.h
@@ -441,6 +441,8 @@ bool iwl_good_plcp_health(struct iwl_priv *priv,
                                 struct iwl_rx_packet *pkt);
 bool iwl_good_ack_health(struct iwl_priv *priv,
                                 struct iwl_rx_packet *pkt);
+void iwl_recover_from_statistics(struct iwl_priv *priv,
+                               struct iwl_rx_packet *pkt);
 void iwl_rx_statistics(struct iwl_priv *priv,
                              struct iwl_rx_mem_buffer *rxb);
 void iwl_reply_statistics(struct iwl_priv *priv,

diff --git a/drivers/net/wireless/iwlwifi/iwl-rx.c b/drivers/net/wireless/iwlwifi/iwl-rx.c
index d661fce..c7c8d8a 100644 (file)
--- a/drivers/net/wireless/iwlwifi/iwl-rx.c
+++ b/drivers/net/wireless/iwlwifi/iwl-rx.c
@@ -397,7 +397,7 @@ bool iwl_good_plcp_health(struct iwl_priv *priv,
 }
 EXPORT_SYMBOL(iwl_good_plcp_health);
 
-static void iwl_recover_from_statistics(struct iwl_priv *priv,
+void iwl_recover_from_statistics(struct iwl_priv *priv,
                                struct iwl_rx_packet *pkt)
 {
        if (test_bit(STATUS_EXIT_PENDING, &priv->status))
@@ -428,6 +428,7 @@ static void iwl_recover_from_statistics(struct iwl_priv *priv,
                }
        }
 }
+EXPORT_SYMBOL(iwl_recover_from_statistics);
 
 void iwl_rx_statistics(struct iwl_priv *priv,
                              struct iwl_rx_mem_buffer *rxb)