3 files changed, 56 insertions, 29 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/fw-api-tx.h b/drivers/net/wireless/intel/iwlwifi/mvm/fw-api-tx.h
index 0036d18334af..ba3f0bbddde8 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/fw-api-tx.h
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/fw-api-tx.h
@@ -510,6 +510,9 @@ struct iwl_mvm_tx_resp {
  * @scd_ssn: the index of the last contiguously sent packet
  * @txed: number of Txed frames in this batch
  * @txed_2_done: number of Acked frames in this batch
+ * @reduced_txp: power reduced according to TPC. This is the actual value and
+ *      not a copy from the LQ command. Thus, if not the first rate was used
+ *      for Tx-ing then this value will be set to 0 by FW.
  */
 struct iwl_mvm_ba_notif {
         __le32 sta_addr_lo32;
@@ -524,7 +527,8 @@ struct iwl_mvm_ba_notif {
         __le16 scd_ssn;
         u8 txed;
         u8 txed_2_done;
-        __le16 reserved1;
+        u8 reduced_txp;
+        u8 reserved1;
 } __packed;
 
 /*
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/rs.c b/drivers/net/wireless/intel/iwlwifi/mvm/rs.c
index 7bb6fd0e4391..94caa88df442 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/rs.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/rs.c
@@ -2,6 +2,7 @@
  *
  * Copyright(c) 2005 - 2014 Intel Corporation. All rights reserved.
  * Copyright(c) 2013 - 2015 Intel Mobile Communications GmbH
+ * Copyright(c) 2016 Intel Deutschland GmbH
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of version 2 of the GNU General Public License as
@@ -724,14 +725,28 @@ static int _rs_collect_tx_data(struct iwl_mvm *mvm,
         return 0;
 }
 
-static int rs_collect_tx_data(struct iwl_mvm *mvm,
-                              struct iwl_lq_sta *lq_sta,
-                              struct iwl_scale_tbl_info *tbl,
-                              int scale_index, int attempts, int successes,
-                              u8 reduced_txp)
+static int rs_collect_tpc_data(struct iwl_mvm *mvm,
+                               struct iwl_lq_sta *lq_sta,
+                               struct iwl_scale_tbl_info *tbl,
+                               int scale_index, int attempts, int successes,
+                               u8 reduced_txp)
+{
+        struct iwl_rate_scale_data *window = NULL;
+
+        if (WARN_ON_ONCE(reduced_txp > TPC_MAX_REDUCTION))
+                return -EINVAL;
+
+        window = &tbl->tpc_win[reduced_txp];
+        return  _rs_collect_tx_data(mvm, tbl, scale_index, attempts, successes,
+                                    window);
+}
+
+static int rs_collect_tlc_data(struct iwl_mvm *mvm,
+                               struct iwl_lq_sta *lq_sta,
+                               struct iwl_scale_tbl_info *tbl,
+                               int scale_index, int attempts, int successes)
 {
         struct iwl_rate_scale_data *window = NULL;
-        int ret;
 
         if (scale_index < 0 || scale_index >= IWL_RATE_COUNT)
                 return -EINVAL;
@@ -745,16 +760,6 @@ static int rs_collect_tx_data(struct iwl_mvm *mvm,
 
         /* Select window for current tx bit rate */
         window = &(tbl->win[scale_index]);
-
-        ret = _rs_collect_tx_data(mvm, tbl, scale_index, attempts, successes,
-                                  window);
-        if (ret)
-                return ret;
-
-        if (WARN_ON_ONCE(reduced_txp > TPC_MAX_REDUCTION))
-                return -EINVAL;
-
-        window = &tbl->tpc_win[reduced_txp];
         return _rs_collect_tx_data(mvm, tbl, scale_index, attempts, successes,
                                    window);
 }
@@ -1301,17 +1306,30 @@ void iwl_mvm_rs_tx_status(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
          * first index into rate scale table.
          */
         if (info->flags & IEEE80211_TX_STAT_AMPDU) {
-                /* ampdu_ack_len = 0 marks no BA was received. In this case
-                 * treat it as a single frame loss as we don't want the success
-                 * ratio to dip too quickly because a BA wasn't received
+                rs_collect_tpc_data(mvm, lq_sta, curr_tbl, lq_rate.index,
+                                    info->status.ampdu_len,
+                                    info->status.ampdu_ack_len,
+                                    reduced_txp);
+
+                /* ampdu_ack_len = 0 marks no BA was received. For TLC, treat
+                 * it as a single frame loss as we don't want the success ratio
+                 * to dip too quickly because a BA wasn't received.
+                 * For TPC, there's no need for this optimisation since we want
+                 * to recover very quickly from a bad power reduction and,
+                 * therefore we'd like the success ratio to get an immediate hit
+                 * when failing to get a BA, so we'd switch back to a lower or
+                 * zero power reduction. When FW transmits agg with a rate
+                 * different from the initial rate, it will not use reduced txp
+                 * and will send BA notification twice (one empty with reduced
+                 * txp equal to the value from LQ and one with reduced txp 0).
+                 * We need to update counters for each txp level accordingly.
                  */
                 if (info->status.ampdu_ack_len == 0)
                         info->status.ampdu_len = 1;
 
-                rs_collect_tx_data(mvm, lq_sta, curr_tbl, lq_rate.index,
-                                   info->status.ampdu_len,
-                                   info->status.ampdu_ack_len,
-                                   reduced_txp);
+                rs_collect_tlc_data(mvm, lq_sta, curr_tbl, lq_rate.index,
+                                    info->status.ampdu_len,
+                                    info->status.ampdu_ack_len);
 
                 /* Update success/fail counts if not searching for new mode */
                 if (lq_sta->rs_state == RS_STATE_STAY_IN_COLUMN) {
@@ -1344,9 +1362,13 @@ void iwl_mvm_rs_tx_status(struct iwl_mvm *mvm, struct ieee80211_sta *sta,
                         else
                                 continue;
 
-                        rs_collect_tx_data(mvm, lq_sta, tmp_tbl, lq_rate.index,
-                                           1, i < retries ? 0 : legacy_success,
-                                           reduced_txp);
+                        rs_collect_tpc_data(mvm, lq_sta, tmp_tbl,
+                                            lq_rate.index, 1,
+                                            i < retries ? 0 : legacy_success,
+                                            reduced_txp);
+                        rs_collect_tlc_data(mvm, lq_sta, tmp_tbl,
+                                            lq_rate.index, 1,
+                                            i < retries ? 0 : legacy_success);
                 }
 
                 /* Update success/fail counts if not searching for new mode */
diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/tx.c b/drivers/net/wireless/intel/iwlwifi/mvm/tx.c
index 8bf48a7d0f4e..0914ec2fd574 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/tx.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/tx.c
@@ -1029,7 +1029,6 @@ static void iwl_mvm_rx_tx_cmd_agg(struct iwl_mvm *mvm,
                 struct iwl_mvm_sta *mvmsta = iwl_mvm_sta_from_mac80211(sta);
                 mvmsta->tid_data[tid].rate_n_flags =
                         le32_to_cpu(tx_resp->initial_rate);
-                mvmsta->tid_data[tid].reduced_tpc = tx_resp->reduced_tpc;
                 mvmsta->tid_data[tid].tx_time =
                         le16_to_cpu(tx_resp->wireless_media_time);
         }
@@ -1060,7 +1059,7 @@ static void iwl_mvm_tx_info_from_ba_notif(struct ieee80211_tx_info *info,
         /* TODO: not accounted if the whole A-MPDU failed */
         info->status.tx_time = tid_data->tx_time;
         info->status.status_driver_data[0] =
-                (void *)(uintptr_t)tid_data->reduced_tpc;
+                (void *)(uintptr_t)ba_notif->reduced_txp;
         info->status.status_driver_data[1] =
                 (void *)(uintptr_t)tid_data->rate_n_flags;
 }
@@ -1133,6 +1132,8 @@ void iwl_mvm_rx_ba_notif(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb)
                            scd_flow, ba_resp_scd_ssn, ba_notif->txed,
                            ba_notif->txed_2_done);
 
+        IWL_DEBUG_TX_REPLY(mvm, "reduced txp from ba notif %d\n",
+                           ba_notif->reduced_txp);
         tid_data->next_reclaimed = ba_resp_scd_ssn;
 
         iwl_mvm_check_ratid_empty(mvm, sta, tid);