Return-path: Received: from mx3-rdu2.redhat.com ([66.187.233.73]:40970 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751240AbeDMOot (ORCPT ); Fri, 13 Apr 2018 10:44:49 -0400 From: Stanislaw Gruszka To: linux-wireless@vger.kernel.org Cc: Jakub Kicinski , Stanislaw Gruszka Subject: [PATCH 1/2] mt7601u: use EWMA to calculate avg_rssi Date: Fri, 13 Apr 2018 16:44:37 +0200 Message-Id: <1523630678-8100-1-git-send-email-sgruszka@redhat.com> (sfid-20180413_164454_200614_E61A7BB7) Sender: linux-wireless-owner@vger.kernel.org List-ID: avr_rssi is not calculated correctly as we do not divide result by 256 (mt76 sum avg_rssi1 and avg_rssi2 and divide by 512). However dividing by 256 will make avg_rssi almost the same as last rssi value - not really an average. So use EWMA to calculate avg_rssi. I've chosen weight_rcp=4 to convergence quicker on signal strength changes. Signed-off-by: Stanislaw Gruszka --- drivers/net/wireless/mediatek/mt7601u/mac.c | 4 ++-- drivers/net/wireless/mediatek/mt7601u/mt7601u.h | 5 ++++- drivers/net/wireless/mediatek/mt7601u/phy.c | 10 +++++++--- 3 files changed, 13 insertions(+), 6 deletions(-) diff --git a/drivers/net/wireless/mediatek/mt7601u/mac.c b/drivers/net/wireless/mediatek/mt7601u/mac.c index d6dc59bb00df..8ec18d69f564 100644 --- a/drivers/net/wireless/mediatek/mt7601u/mac.c +++ b/drivers/net/wireless/mediatek/mt7601u/mac.c @@ -437,7 +437,7 @@ void mt7601u_mac_set_ampdu_factor(struct mt7601u_dev *dev) { dev->bcn_freq_off = rxwi->freq_off; dev->bcn_phy_mode = FIELD_GET(MT_RXWI_RATE_PHY, rate); - dev->avg_rssi = (dev->avg_rssi * 15) / 16 + (rssi << 8); + ewma_rssi_add(&dev->avg_rssi, -rssi); } static int @@ -479,7 +479,7 @@ u32 mt76_mac_process_rx(struct mt7601u_dev *dev, struct sk_buff *skb, if (mt7601u_rx_is_our_beacon(dev, data)) mt7601u_rx_monitor_beacon(dev, rxwi, rate, rssi); else if (rxwi->rxinfo & cpu_to_le32(MT_RXINFO_U2M)) - dev->avg_rssi = (dev->avg_rssi * 15) / 16 + (rssi << 8); + ewma_rssi_add(&dev->avg_rssi, -rssi); spin_unlock_bh(&dev->con_mon_lock); return len; diff --git a/drivers/net/wireless/mediatek/mt7601u/mt7601u.h b/drivers/net/wireless/mediatek/mt7601u/mt7601u.h index c7ec40475a5f..9058b0af7bec 100644 --- a/drivers/net/wireless/mediatek/mt7601u/mt7601u.h +++ b/drivers/net/wireless/mediatek/mt7601u/mt7601u.h @@ -23,6 +23,7 @@ #include #include #include +#include #include "regs.h" @@ -138,6 +139,8 @@ enum { MT7601U_STATE_MORE_STATS, }; +DECLARE_EWMA(rssi, 10, 4); + /** * struct mt7601u_dev - adapter structure * @lock: protects @wcid->tx_rate. @@ -219,7 +222,7 @@ struct mt7601u_dev { s8 bcn_freq_off; u8 bcn_phy_mode; - int avg_rssi; /* starts at 0 and converges */ + struct ewma_rssi avg_rssi; u8 agc_save; diff --git a/drivers/net/wireless/mediatek/mt7601u/phy.c b/drivers/net/wireless/mediatek/mt7601u/phy.c index ca09a5d4305e..d440c550bdb1 100644 --- a/drivers/net/wireless/mediatek/mt7601u/phy.c +++ b/drivers/net/wireless/mediatek/mt7601u/phy.c @@ -974,6 +974,7 @@ void mt7601u_agc_restore(struct mt7601u_dev *dev) static void mt7601u_agc_tune(struct mt7601u_dev *dev) { u8 val = mt7601u_agc_default(dev); + long avg_rssi; if (test_bit(MT7601U_STATE_SCANNING, &dev->state)) return; @@ -983,9 +984,12 @@ static void mt7601u_agc_tune(struct mt7601u_dev *dev) * Rssi updates are only on beacons and U2M so should work... */ spin_lock_bh(&dev->con_mon_lock); - if (dev->avg_rssi <= -70) + avg_rssi = ewma_rssi_read(&dev->avg_rssi); + WARN_ON_ONCE(avg_rssi == 0); + avg_rssi = -avg_rssi; + if (avg_rssi <= -70) val -= 0x20; - else if (dev->avg_rssi <= -60) + else if (avg_rssi <= -60) val -= 0x10; spin_unlock_bh(&dev->con_mon_lock); @@ -1101,7 +1105,7 @@ void mt7601u_phy_con_cal_onoff(struct mt7601u_dev *dev, /* Start/stop collecting beacon data */ spin_lock_bh(&dev->con_mon_lock); ether_addr_copy(dev->ap_bssid, info->bssid); - dev->avg_rssi = 0; + ewma_rssi_init(&dev->avg_rssi); dev->bcn_freq_off = MT_FREQ_OFFSET_INVALID; spin_unlock_bh(&dev->con_mon_lock); -- 1.9.3