1 files changed, 54 insertions, 0 deletions

diff --git a/drivers/net/wireless/iwlwifi/iwl-rx.c b/drivers/net/wireless/iwlwifi/iwl-rx.c
index dc06c7bb0f5c..ea309f42a78a 100644
--- a/drivers/net/wireless/iwlwifi/iwl-rx.c
+++ b/drivers/net/wireless/iwlwifi/iwl-rx.c
@@ -602,11 +602,15 @@ static void iwl_accumulative_statistics(struct iwl_priv *priv,
 
 #define REG_RECALIB_PERIOD (60)
 
+#define PLCP_MSG "plcp_err exceeded %u, %u, %u, %u, %u, %d, %u mSecs\n"
 void iwl_rx_statistics(struct iwl_priv *priv,
                               struct iwl_rx_mem_buffer *rxb)
 {
         int change;
         struct iwl_rx_packet *pkt = rxb_addr(rxb);
+        int combined_plcp_delta;
+        unsigned int plcp_msec;
+        unsigned long plcp_received_jiffies;
 
         IWL_DEBUG_RX(priv, "Statistics notification received (%d vs %d).\n",
                      (int)sizeof(priv->statistics),
@@ -621,6 +625,56 @@ void iwl_rx_statistics(struct iwl_priv *priv,
 #ifdef CONFIG_IWLWIFI_DEBUG
         iwl_accumulative_statistics(priv, (__le32 *)&pkt->u.stats);
 #endif
+        /*
+         * 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(pkt->u.stats.rx.ofdm.plcp_err) -
+                        le32_to_cpu(priv->statistics.rx.ofdm.plcp_err)) +
+                        (le32_to_cpu(pkt->u.stats.rx.ofdm_ht.plcp_err) -
+                        le32_to_cpu(priv->statistics.rx.ofdm_ht.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,
+                         *    Received ofdm_ht.plcp_err,
+                         *    Current ofdm_ht.plcp_err,
+                         *    combined_plcp_delta,
+                         *    plcp_msec
+                         */
+                        IWL_DEBUG_RADIO(priv, PLCP_MSG,
+                                priv->cfg->plcp_delta_threshold,
+                                le32_to_cpu(pkt->u.stats.rx.ofdm.plcp_err),
+                                le32_to_cpu(priv->statistics.rx.ofdm.plcp_err),
+                                le32_to_cpu(pkt->u.stats.rx.ofdm_ht.plcp_err),
+                                le32_to_cpu(
+                                        priv->statistics.rx.ofdm_ht.plcp_err),
+                                combined_plcp_delta, plcp_msec);
+
+                        /*
+                         * Reset the RF radio due to the high plcp
+                         * error rate
+                         */
+                        iwl_force_rf_reset(priv);
+                }
+        }
+
         memcpy(&priv->statistics, &pkt->u.stats, sizeof(priv->statistics));
 
         set_bit(STATUS_STATISTICS, &priv->status);