qcacmn: fix incorrect ext_stats calculation

Currently when query REO stats, each time REO will response
cumulative REO stats per TID, while host side count them as
delta stats between each query.
Reset host stats to 0 before each query, and if query timeout
happened, use the last saved stats for this time query.

Change-Id: I29e986b3c8859f5c3d1b557d9cc980a52219d664
CRs-Fixed: 2743352

dp/wifi3.0/dp_main.c

@@ -10530,6 +10530,8 @@ dp_request_rx_hw_stats(struct cdp_soc_t *soc_hdl, uint8_t vdev_id)
 	QDF_STATUS status;
 	struct dp_req_rx_hw_stats_t *rx_hw_stats;
 	int rx_stats_sent_cnt = 0;
+	uint32_t last_rx_mpdu_received;
+	uint32_t last_rx_mpdu_missed;
 
 	if (!vdev) {
 		dp_err("vdev is null for vdev_id: %u", vdev_id);
@@ -10553,6 +10555,12 @@ dp_request_rx_hw_stats(struct cdp_soc_t *soc_hdl, uint8_t vdev_id)
 
 	qdf_event_reset(&soc->rx_hw_stats_event);
 	qdf_spin_lock_bh(&soc->rx_hw_stats_lock);
+	/* save the last soc cumulative stats and reset it to 0 */
+	last_rx_mpdu_received = soc->ext_stats.rx_mpdu_received;
+	last_rx_mpdu_missed = soc->ext_stats.rx_mpdu_missed;
+	soc->ext_stats.rx_mpdu_received = 0;
+	soc->ext_stats.rx_mpdu_missed = 0;
+
 	rx_stats_sent_cnt =
 		dp_peer_rxtid_stats(peer, dp_rx_hw_stats_cb, rx_hw_stats);
 	if (!rx_stats_sent_cnt) {
@@ -10576,6 +10584,12 @@ dp_request_rx_hw_stats(struct cdp_soc_t *soc_hdl, uint8_t vdev_id)
 		dp_info("rx hw stats event timeout");
 		if (soc->is_last_stats_ctx_init)
 			rx_hw_stats->is_query_timeout = true;
+		/**
+		 * If query timeout happened, use the last saved stats
+		 * for this time query.
+		 */
+		soc->ext_stats.rx_mpdu_received = last_rx_mpdu_received;
+		soc->ext_stats.rx_mpdu_missed = last_rx_mpdu_missed;
 	}
 	qdf_spin_unlock_bh(&soc->rx_hw_stats_lock);
 	dp_peer_unref_delete(peer);