mt76: mt7615: sync with mt7603 rate control changes

- Store the previous and current rate set in the driver + the TSF value
  at the time of the switch.
- Use the tx status TSF value to determine which rate set needs to be used
  as reference.
- Report only short or long GI rates for a single status event, not a mix.
- The hardware reports the last used rate index. Use it along with the
  retry count to figure out what rate was used for the first attempt.
- Use the same retry count value for all rate slots to make this calculation
  work.
- Derive the probe rate from the current rateset instead of the skb cb
- Do not wait for a status report for the probe frame before removing the
  probe rate from the rate table. Do it immediately after it was referenced
  in a tx status report.
- Use the first half of the first rate retry budget for the probe rate
  in order to avoid using too many retries on that rate
- Switch from lower rates to higher rates more conservatively
- enable hardware rate up/down selection

Reviewed-by: Ryder Lee <ryder.lee@mediatek.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

diff --git a/drivers/net/wireless/mediatek/mt76/mt7615/init.c b/drivers/net/wireless/mediatek/mt76/mt7615/init.c
index a6c2a13..280db94 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt7615/init.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7615/init.c
@@ -45,11 +45,19 @@ static void mt7615_mac_init(struct mt7615_dev *dev)
        mt76_wr(dev, MT_DMA_DCR0, MT_DMA_DCR0_RX_VEC_DROP |
                FIELD_PREP(MT_DMA_DCR0_MAX_RX_LEN, 3072));
 
-       mt76_wr(dev, MT_AGG_ARUCR, FIELD_PREP(MT_AGG_ARxCR_LIMIT(0), 7));
+       mt76_wr(dev, MT_AGG_ARUCR,
+               FIELD_PREP(MT_AGG_ARxCR_LIMIT(0), 7) |
+               FIELD_PREP(MT_AGG_ARxCR_LIMIT(1), 2) |
+               FIELD_PREP(MT_AGG_ARxCR_LIMIT(2), 2) |
+               FIELD_PREP(MT_AGG_ARxCR_LIMIT(3), 2) |
+               FIELD_PREP(MT_AGG_ARxCR_LIMIT(4), 1) |
+               FIELD_PREP(MT_AGG_ARxCR_LIMIT(5), 1) |
+               FIELD_PREP(MT_AGG_ARxCR_LIMIT(6), 1) |
+               FIELD_PREP(MT_AGG_ARxCR_LIMIT(7), 1));
+
        mt76_wr(dev, MT_AGG_ARDCR,
-               FIELD_PREP(MT_AGG_ARxCR_LIMIT(0), 0) |
-               FIELD_PREP(MT_AGG_ARxCR_LIMIT(1),
-                          max_t(int, 0, MT7615_RATE_RETRY - 2)) |
+               FIELD_PREP(MT_AGG_ARxCR_LIMIT(0), MT7615_RATE_RETRY - 1) |
+               FIELD_PREP(MT_AGG_ARxCR_LIMIT(1), MT7615_RATE_RETRY - 1) |
                FIELD_PREP(MT_AGG_ARxCR_LIMIT(2), MT7615_RATE_RETRY - 1) |
                FIELD_PREP(MT_AGG_ARxCR_LIMIT(3), MT7615_RATE_RETRY - 1) |
                FIELD_PREP(MT_AGG_ARxCR_LIMIT(4), MT7615_RATE_RETRY - 1) |
@@ -58,8 +66,7 @@ static void mt7615_mac_init(struct mt7615_dev *dev)
                FIELD_PREP(MT_AGG_ARxCR_LIMIT(7), MT7615_RATE_RETRY - 1));
 
        mt76_wr(dev, MT_AGG_ARCR,
-               (MT_AGG_ARCR_INIT_RATE1 |
-                FIELD_PREP(MT_AGG_ARCR_RTS_RATE_THR, 2) |
+               (FIELD_PREP(MT_AGG_ARCR_RTS_RATE_THR, 2) |
                 MT_AGG_ARCR_RATE_DOWN_RATIO_EN |
                 FIELD_PREP(MT_AGG_ARCR_RATE_DOWN_RATIO, 1) |
                 FIELD_PREP(MT_AGG_ARCR_RATE_UP_EXTRA_TH, 4)));

diff --git a/drivers/net/wireless/mediatek/mt76/mt7615/mac.c b/drivers/net/wireless/mediatek/mt76/mt7615/mac.c
index b896d8c..5bfb459 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt7615/mac.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7615/mac.c
@@ -451,6 +451,7 @@ void mt7615_mac_set_rates(struct mt7615_dev *dev, struct mt7615_sta *sta,
                          struct ieee80211_tx_rate *probe_rate,
                          struct ieee80211_tx_rate *rates)
 {
+       struct ieee80211_tx_rate *ref;
        int wcid = sta->wcid.idx;
        u32 addr = MT_WTBL_BASE + wcid * MT_WTBL_ENTRY_SIZE;
        bool stbc = false;
@@ -459,7 +460,8 @@ void mt7615_mac_set_rates(struct mt7615_dev *dev, struct mt7615_sta *sta,
        u16 val[4];
        u16 probe_val;
        u32 w5, w27;
-       int i;
+       bool rateset;
+       int i, k;
 
        if (!mt76_poll(dev, MT_WTBL_UPDATE, MT_WTBL_UPDATE_BUSY, 0, 5000))
                return;
@@ -467,6 +469,43 @@ void mt7615_mac_set_rates(struct mt7615_dev *dev, struct mt7615_sta *sta,
        for (i = n_rates; i < 4; i++)
                rates[i] = rates[n_rates - 1];
 
+       rateset = !(sta->rate_set_tsf & BIT(0));
+       memcpy(sta->rateset[rateset].rates, rates,
+              sizeof(sta->rateset[rateset].rates));
+       if (probe_rate) {
+               sta->rateset[rateset].probe_rate = *probe_rate;
+               ref = &sta->rateset[rateset].probe_rate;
+       } else {
+               sta->rateset[rateset].probe_rate.idx = -1;
+               ref = &sta->rateset[rateset].rates[0];
+       }
+
+       rates = sta->rateset[rateset].rates;
+       for (i = 0; i < ARRAY_SIZE(sta->rateset[rateset].rates); i++) {
+               /*
+                * We don't support switching between short and long GI
+                * within the rate set. For accurate tx status reporting, we
+                * need to make sure that flags match.
+                * For improved performance, avoid duplicate entries by
+                * decrementing the MCS index if necessary
+                */
+               if ((ref->flags ^ rates[i].flags) & IEEE80211_TX_RC_SHORT_GI)
+                       rates[i].flags ^= IEEE80211_TX_RC_SHORT_GI;
+
+               for (k = 0; k < i; k++) {
+                       if (rates[i].idx != rates[k].idx)
+                               continue;
+                       if ((rates[i].flags ^ rates[k].flags) &
+                           (IEEE80211_TX_RC_40_MHZ_WIDTH |
+                            IEEE80211_TX_RC_80_MHZ_WIDTH |
+                            IEEE80211_TX_RC_160_MHZ_WIDTH))
+                               continue;
+
+                       rates[i].idx--;
+               }
+
+       }
+
        val[0] = mt7615_mac_tx_rate_val(dev, &rates[0], stbc, &bw);
        bw_prev = bw;
 
@@ -513,17 +552,17 @@ void mt7615_mac_set_rates(struct mt7615_dev *dev, struct mt7615_sta *sta,
        mt76_wr(dev, MT_WTBL_RIUCR1,
                FIELD_PREP(MT_WTBL_RIUCR1_RATE0, probe_val) |
                FIELD_PREP(MT_WTBL_RIUCR1_RATE1, val[0]) |
-               FIELD_PREP(MT_WTBL_RIUCR1_RATE2_LO, val[0]));
+               FIELD_PREP(MT_WTBL_RIUCR1_RATE2_LO, val[1]));
 
        mt76_wr(dev, MT_WTBL_RIUCR2,
-               FIELD_PREP(MT_WTBL_RIUCR2_RATE2_HI, val[0] >> 8) |
+               FIELD_PREP(MT_WTBL_RIUCR2_RATE2_HI, val[1] >> 8) |
                FIELD_PREP(MT_WTBL_RIUCR2_RATE3, val[1]) |
-               FIELD_PREP(MT_WTBL_RIUCR2_RATE4, val[1]) |
+               FIELD_PREP(MT_WTBL_RIUCR2_RATE4, val[2]) |
                FIELD_PREP(MT_WTBL_RIUCR2_RATE5_LO, val[2]));
 
        mt76_wr(dev, MT_WTBL_RIUCR3,
                FIELD_PREP(MT_WTBL_RIUCR3_RATE5_HI, val[2] >> 4) |
-               FIELD_PREP(MT_WTBL_RIUCR3_RATE6, val[2]) |
+               FIELD_PREP(MT_WTBL_RIUCR3_RATE6, val[3]) |
                FIELD_PREP(MT_WTBL_RIUCR3_RATE7, val[3]));
 
        mt76_wr(dev, MT_WTBL_UPDATE,
@@ -533,6 +572,9 @@ void mt7615_mac_set_rates(struct mt7615_dev *dev, struct mt7615_sta *sta,
 
        mt76_wr(dev, addr + 27 * 4, w27);
 
+       mt76_set(dev, MT_LPON_T0CR, MT_LPON_T0CR_MODE); /* TSF read */
+       sta->rate_set_tsf = (mt76_rr(dev, MT_LPON_UTTR0) & ~BIT(0)) | rateset;
+
        if (!(sta->wcid.tx_info & MT_WCID_TX_INFO_SET))
                mt76_poll(dev, MT_WTBL_UPDATE, MT_WTBL_UPDATE_BUSY, 0, 5000);
 
@@ -562,9 +604,9 @@ int mt7615_tx_prepare_skb(struct mt76_dev *mdev, void *txwi_ptr,
 
        if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) {
                spin_lock_bh(&dev->mt76.lock);
-               msta->rate_probe = true;
                mt7615_mac_set_rates(dev, msta, &info->control.rates[0],
                                     msta->rates);
+               msta->rate_probe = true;
                spin_unlock_bh(&dev->mt76.lock);
        }
 
@@ -616,9 +658,13 @@ static bool mt7615_fill_txs(struct mt7615_dev *dev, struct mt7615_sta *sta,
                            struct ieee80211_tx_info *info, __le32 *txs_data)
 {
        struct ieee80211_supported_band *sband;
-       int i, idx, count, final_idx = 0;
+       struct mt7615_rate_set *rs;
+       int first_idx = 0, last_idx;
+       int i, idx, count;
        bool fixed_rate, ack_timeout;
        bool probe, ampdu, cck = false;
+       bool rs_idx;
+       u32 rate_set_tsf;
        u32 final_rate, final_rate_flags, final_nss, txs;
 
        fixed_rate = info->status.rates[0].count;
@@ -629,6 +675,7 @@ static bool mt7615_fill_txs(struct mt7615_dev *dev, struct mt7615_sta *sta,
 
        txs = le32_to_cpu(txs_data[3]);
        count = FIELD_GET(MT_TXS3_TX_COUNT, txs);
+       last_idx = FIELD_GET(MT_TXS3_LAST_TX_RATE, txs);
 
        txs = le32_to_cpu(txs_data[0]);
        final_rate = FIELD_GET(MT_TXS0_TX_RATE, txs);
@@ -650,38 +697,56 @@ static bool mt7615_fill_txs(struct mt7615_dev *dev, struct mt7615_sta *sta,
        if (ampdu || (info->flags & IEEE80211_TX_CTL_AMPDU))
                info->flags |= IEEE80211_TX_STAT_AMPDU | IEEE80211_TX_CTL_AMPDU;
 
+       first_idx = max_t(int, 0, last_idx - (count + 1) / MT7615_RATE_RETRY);
+
        if (fixed_rate && !probe) {
                info->status.rates[0].count = count;
+               i = 0;
                goto out;
        }
 
-       for (i = 0, idx = 0; i < ARRAY_SIZE(info->status.rates); i++) {
-               int cur_count = min_t(int, count, 2 * MT7615_RATE_RETRY);
+       rate_set_tsf = READ_ONCE(sta->rate_set_tsf);
+       rs_idx = !((u32)(FIELD_GET(MT_TXS4_F0_TIMESTAMP, le32_to_cpu(txs_data[4])) -
+                        rate_set_tsf) < 1000000);
+       rs_idx ^= rate_set_tsf & BIT(0);
+       rs = &sta->rateset[rs_idx];
 
-               if (!i && probe) {
-                       cur_count = 1;
-               } else {
-                       info->status.rates[i] = sta->rates[idx];
-                       idx++;
-               }
+       if (!first_idx && rs->probe_rate.idx >= 0) {
+               info->status.rates[0] = rs->probe_rate;
 
-               if (i && info->status.rates[i].idx < 0) {
-                       info->status.rates[i - 1].count += count;
-                       break;
+               spin_lock_bh(&dev->mt76.lock);
+               if (sta->rate_probe) {
+                       mt7615_mac_set_rates(dev, sta, NULL, sta->rates);
+                       sta->rate_probe = false;
                }
+               spin_unlock_bh(&dev->mt76.lock);
+       } else
+               info->status.rates[0] = rs->rates[first_idx / 2];
+       info->status.rates[0].count = 0;
 
-               if (!count) {
-                       info->status.rates[i].idx = -1;
-                       break;
-               }
+       for (i = 0, idx = first_idx; count && idx <= last_idx; idx++) {
+               struct ieee80211_tx_rate *cur_rate;
+               int cur_count;
 
-               info->status.rates[i].count = cur_count;
-               final_idx = i;
+               cur_rate = &rs->rates[idx / 2];
+               cur_count = min_t(int, MT7615_RATE_RETRY, count);
                count -= cur_count;
+
+               if (idx && (cur_rate->idx != info->status.rates[i].idx ||
+                           cur_rate->flags != info->status.rates[i].flags)) {
+                       i++;
+                       if (i == ARRAY_SIZE(info->status.rates))
+                               break;
+
+                       info->status.rates[i] = *cur_rate;
+                       info->status.rates[i].count = 0;
+               }
+
+               info->status.rates[i].count += cur_count;
        }
 
 out:
-       final_rate_flags = info->status.rates[final_idx].flags;
+       final_rate_flags = info->status.rates[i].flags;
 
        switch (FIELD_GET(MT_TX_RATE_MODE, final_rate)) {
        case MT_PHY_TYPE_CCK:
@@ -713,8 +778,8 @@ out:
                return false;
        }
 
-       info->status.rates[final_idx].idx = final_rate;
-       info->status.rates[final_idx].flags = final_rate_flags;
+       info->status.rates[i].idx = final_rate;
+       info->status.rates[i].flags = final_rate_flags;
 
        return true;
 }
@@ -735,16 +800,6 @@ static bool mt7615_mac_add_txs_skb(struct mt7615_dev *dev,
        if (skb) {
                struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 
-               if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) {
-                       spin_lock_bh(&dev->mt76.lock);
-                       if (sta->rate_probe) {
-                               mt7615_mac_set_rates(dev, sta, NULL,
-                                                    sta->rates);
-                               sta->rate_probe = false;
-                       }
-                       spin_unlock_bh(&dev->mt76.lock);
-               }
-
                if (!mt7615_fill_txs(dev, sta, info, txs_data)) {
                        ieee80211_tx_info_clear_status(info);
                        info->status.rates[0].idx = -1;

diff --git a/drivers/net/wireless/mediatek/mt76/mt7615/mt7615.h b/drivers/net/wireless/mediatek/mt76/mt7615/mt7615.h
index 1135023..2f43101 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt7615/mt7615.h
+++ b/drivers/net/wireless/mediatek/mt76/mt7615/mt7615.h
@@ -42,12 +42,21 @@ enum mt7615_hw_txq_id {
        MT7615_TXQ_FWDL,
 };
 
+struct mt7615_rate_set {
+       struct ieee80211_tx_rate probe_rate;
+       struct ieee80211_tx_rate rates[4];
+};
+
 struct mt7615_sta {
        struct mt76_wcid wcid; /* must be first */
 
        struct mt7615_vif *vif;
 
-       struct ieee80211_tx_rate rates[8];
+       struct ieee80211_tx_rate rates[4];
+
+       struct mt7615_rate_set rateset[2];
+       u32 rate_set_tsf;
+
        u8 rate_count;
        u8 n_rates;
 

diff --git a/drivers/net/wireless/mediatek/mt76/mt7615/regs.h b/drivers/net/wireless/mediatek/mt76/mt7615/regs.h
index ea40581..f2cd858 100644 (file)
--- a/drivers/net/wireless/mediatek/mt76/mt7615/regs.h
+++ b/drivers/net/wireless/mediatek/mt76/mt7615/regs.h
@@ -187,6 +187,15 @@
 
 #define MT_WTBL_W27_CC_BW_SEL          GENMASK(6, 5)
 
+#define MT_LPON_BASE                   0x24200
+#define MT_LPON(_n)                    (MT_LPON_BASE + (_n))
+
+#define MT_LPON_T0CR                   MT_LPON(0x010)
+#define MT_LPON_T0CR_MODE              GENMASK(1, 0)
+
+#define MT_LPON_UTTR0                  MT_LPON(0x018)
+#define MT_LPON_UTTR1                  MT_LPON(0x01c)
+
 #define MT_EFUSE_BASE                  0x81070000
 #define MT_EFUSE_BASE_CTRL             0x000
 #define MT_EFUSE_BASE_CTRL_EMPTY       BIT(30)