iwlwifi: mvm: add traffic condition monitoring (TCM)

Traffic condition monitor gathers data about the traffic load and
other conditions and can be used to make decisions regarding latency,
throughput etc.  This patch introduces the code and data structures to
collect this data for future use.

Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

1 files changed, 57 insertions, 3 deletions

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/rx.c b/drivers/net/wireless/intel/iwlwifi/mvm/rx.c
index d26833c5ce1f..be80294349c3 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/rx.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/rx.c
@@ -254,6 +254,39 @@ static u32 iwl_mvm_set_mac80211_rx_flag(struct iwl_mvm *mvm,
 	return 0;
 }
 
+static void iwl_mvm_rx_handle_tcm(struct iwl_mvm *mvm,
+				  struct ieee80211_sta *sta,
+				  struct ieee80211_hdr *hdr, u32 len,
+				  struct iwl_rx_phy_info *phy_info,
+				  u32 rate_n_flags)
+{
+	struct iwl_mvm_sta *mvmsta;
+	struct iwl_mvm_tcm_mac *mdata;
+	int mac;
+	int ac = IEEE80211_AC_BE; /* treat non-QoS as BE */
+
+	if (ieee80211_is_data_qos(hdr->frame_control))
+		ac = tid_to_mac80211_ac[ieee80211_get_tid(hdr)];
+
+	mvmsta = iwl_mvm_sta_from_mac80211(sta);
+	mac = mvmsta->mac_id_n_color & FW_CTXT_ID_MSK;
+
+	if (time_after(jiffies, mvm->tcm.ts + MVM_TCM_PERIOD))
+		schedule_delayed_work(&mvm->tcm.work, 0);
+	mdata = &mvm->tcm.data[mac];
+	mdata->rx.pkts[ac]++;
+
+	/* count the airtime only once for each ampdu */
+	if (mdata->rx.last_ampdu_ref != mvm->ampdu_ref) {
+		mdata->rx.last_ampdu_ref = mvm->ampdu_ref;
+		mdata->rx.airtime += le16_to_cpu(phy_info->frame_time);
+	}
+
+	if (!(rate_n_flags & (RATE_MCS_HT_MSK | RATE_MCS_VHT_MSK)))
+		return;
+
+}
+
 static void iwl_mvm_rx_csum(struct ieee80211_sta *sta,
 			    struct sk_buff *skb,
 			    u32 status)
@@ -408,6 +441,12 @@ void iwl_mvm_rx_rx_mpdu(struct iwl_mvm *mvm, struct napi_struct *napi,
 							NULL);
 		}
 
+		if (!mvm->tcm.paused && len >= sizeof(*hdr) &&
+		    !is_multicast_ether_addr(hdr->addr1) &&
+		    ieee80211_is_data(hdr->frame_control))
+			iwl_mvm_rx_handle_tcm(mvm, sta, hdr, len, phy_info,
+					      rate_n_flags);
+
 		if (ieee80211_is_data(hdr->frame_control))
 			iwl_mvm_rx_csum(sta, skb, rx_pkt_status);
 	}
@@ -654,7 +693,7 @@ void iwl_mvm_handle_rx_statistics(struct iwl_mvm *mvm,
 	int expected_size;
 	int i;
 	u8 *energy;
-	__le32 *bytes, *air_time;
+	__le32 *air_time;
 	__le32 flags;
 
 	if (!iwl_mvm_has_new_rx_stats_api(mvm)) {
@@ -729,13 +768,11 @@ void iwl_mvm_handle_rx_statistics(struct iwl_mvm *mvm,
 		struct iwl_notif_statistics_v11 *v11 = (void *)&pkt->data;
 
 		energy = (void *)&v11->load_stats.avg_energy;
-		bytes = (void *)&v11->load_stats.byte_count;
 		air_time = (void *)&v11->load_stats.air_time;
 	} else {
 		struct iwl_notif_statistics_cdb *stats = (void *)&pkt->data;
 
 		energy = (void *)&stats->load_stats.avg_energy;
-		bytes = (void *)&stats->load_stats.byte_count;
 		air_time = (void *)&stats->load_stats.air_time;
 	}
 
@@ -752,6 +789,23 @@ void iwl_mvm_handle_rx_statistics(struct iwl_mvm *mvm,
 		sta->avg_energy = energy[i];
 	}
 	rcu_read_unlock();
+
+	/*
+	 * Don't update in case the statistics are not cleared, since
+	 * we will end up counting twice the same airtime, once in TCM
+	 * request and once in statistics notification.
+	 */
+	if (!(le32_to_cpu(flags) & IWL_STATISTICS_REPLY_FLG_CLEAR))
+		return;
+
+	spin_lock(&mvm->tcm.lock);
+	for (i = 0; i < NUM_MAC_INDEX_DRIVER; i++) {
+		struct iwl_mvm_tcm_mac *mdata = &mvm->tcm.data[i];
+		u32 airtime = le32_to_cpu(air_time[i]);
+
+		mdata->rx.airtime += airtime;
+	}
+	spin_unlock(&mvm->tcm.lock);
 }
 
 void iwl_mvm_rx_statistics(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb)