1 /* 2 * Copyright (C) 2014 Felix Fietkau <nbd@openwrt.org> 3 * Copyright (C) 2015 Jakub Kicinski <kubakici@wp.pl> 4 * 5 * This program is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License version 2 7 * as published by the Free Software Foundation 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU General Public License for more details. 13 */ 14 15 #include "mt7601u.h" 16 #include "trace.h" 17 18 enum mt76_txq_id { 19 MT_TXQ_VO = IEEE80211_AC_VO, 20 MT_TXQ_VI = IEEE80211_AC_VI, 21 MT_TXQ_BE = IEEE80211_AC_BE, 22 MT_TXQ_BK = IEEE80211_AC_BK, 23 MT_TXQ_PSD, 24 MT_TXQ_MCU, 25 __MT_TXQ_MAX 26 }; 27 28 /* Hardware uses mirrored order of queues with Q0 having the highest priority */ 29 static u8 q2hwq(u8 q) 30 { 31 return q ^ 0x3; 32 } 33 34 /* Take mac80211 Q id from the skb and translate it to hardware Q id */ 35 static u8 skb2q(struct sk_buff *skb) 36 { 37 int qid = skb_get_queue_mapping(skb); 38 39 if (WARN_ON(qid >= MT_TXQ_PSD)) { 40 qid = MT_TXQ_BE; 41 skb_set_queue_mapping(skb, qid); 42 } 43 44 return q2hwq(qid); 45 } 46 47 /* Note: TX retry reporting is a bit broken. 48 * Retries are reported only once per AMPDU and often come a frame early 49 * i.e. they are reported in the last status preceding the AMPDU. Apart 50 * from the fact that it's hard to know the length of the AMPDU (which is 51 * required to know to how many consecutive frames retries should be 52 * applied), if status comes early on full FIFO it gets lost and retries 53 * of the whole AMPDU become invisible. 54 * As a work-around encode the desired rate in PKT_ID of TX descriptor 55 * and based on that guess the retries (every rate is tried once). 56 * Only downside here is that for MCS0 we have to rely solely on 57 * transmission failures as no retries can ever be reported. 58 * Not having to read EXT_FIFO has a nice effect of doubling the number 59 * of reports which can be fetched. 60 * Also the vendor driver never uses the EXT_FIFO register so it may be 61 * undertested. 62 */ 63 static u8 mt7601u_tx_pktid_enc(struct mt7601u_dev *dev, u8 rate, bool is_probe) 64 { 65 u8 encoded = (rate + 1) + is_probe * 8; 66 67 /* Because PKT_ID 0 disables status reporting only 15 values are 68 * available but 16 are needed (8 MCS * 2 for encoding is_probe) 69 * - we need to cram together two rates. MCS0 and MCS7 with is_probe 70 * share PKT_ID 9. 71 */ 72 if (is_probe && rate == 7) 73 return encoded - 7; 74 75 return encoded; 76 } 77 78 static void 79 mt7601u_tx_pktid_dec(struct mt7601u_dev *dev, struct mt76_tx_status *stat) 80 { 81 u8 req_rate = stat->pktid; 82 u8 eff_rate = stat->rate & 0x7; 83 84 req_rate -= 1; 85 86 if (req_rate > 7) { 87 stat->is_probe = true; 88 req_rate -= 8; 89 90 /* Decide between MCS0 and MCS7 which share pktid 9 */ 91 if (!req_rate && eff_rate) 92 req_rate = 7; 93 } 94 95 stat->retry = req_rate - eff_rate; 96 } 97 98 static void mt7601u_tx_skb_remove_dma_overhead(struct sk_buff *skb, 99 struct ieee80211_tx_info *info) 100 { 101 int pkt_len = (unsigned long)info->status.status_driver_data[0]; 102 103 skb_pull(skb, sizeof(struct mt76_txwi) + 4); 104 if (ieee80211_get_hdrlen_from_skb(skb) % 4) 105 mt76_remove_hdr_pad(skb); 106 107 skb_trim(skb, pkt_len); 108 } 109 110 void mt7601u_tx_status(struct mt7601u_dev *dev, struct sk_buff *skb) 111 { 112 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 113 114 mt7601u_tx_skb_remove_dma_overhead(skb, info); 115 116 ieee80211_tx_info_clear_status(info); 117 info->status.rates[0].idx = -1; 118 info->flags |= IEEE80211_TX_STAT_ACK; 119 120 spin_lock(&dev->mac_lock); 121 ieee80211_tx_status(dev->hw, skb); 122 spin_unlock(&dev->mac_lock); 123 } 124 125 static int mt7601u_skb_rooms(struct mt7601u_dev *dev, struct sk_buff *skb) 126 { 127 int hdr_len = ieee80211_get_hdrlen_from_skb(skb); 128 u32 need_head; 129 130 need_head = sizeof(struct mt76_txwi) + 4; 131 if (hdr_len % 4) 132 need_head += 2; 133 134 return skb_cow(skb, need_head); 135 } 136 137 static struct mt76_txwi * 138 mt7601u_push_txwi(struct mt7601u_dev *dev, struct sk_buff *skb, 139 struct ieee80211_sta *sta, struct mt76_wcid *wcid, 140 int pkt_len) 141 { 142 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 143 struct ieee80211_tx_rate *rate = &info->control.rates[0]; 144 struct mt76_txwi *txwi; 145 unsigned long flags; 146 bool is_probe; 147 u32 pkt_id; 148 u16 rate_ctl; 149 u8 nss; 150 151 txwi = skb_push(skb, sizeof(struct mt76_txwi)); 152 memset(txwi, 0, sizeof(*txwi)); 153 154 if (!wcid->tx_rate_set) 155 ieee80211_get_tx_rates(info->control.vif, sta, skb, 156 info->control.rates, 1); 157 158 spin_lock_irqsave(&dev->lock, flags); 159 if (rate->idx < 0 || !rate->count) 160 rate_ctl = wcid->tx_rate; 161 else 162 rate_ctl = mt76_mac_tx_rate_val(dev, rate, &nss); 163 spin_unlock_irqrestore(&dev->lock, flags); 164 txwi->rate_ctl = cpu_to_le16(rate_ctl); 165 166 if (!(info->flags & IEEE80211_TX_CTL_NO_ACK)) 167 txwi->ack_ctl |= MT_TXWI_ACK_CTL_REQ; 168 if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) 169 txwi->ack_ctl |= MT_TXWI_ACK_CTL_NSEQ; 170 171 if ((info->flags & IEEE80211_TX_CTL_AMPDU) && sta) { 172 u8 ba_size = IEEE80211_MIN_AMPDU_BUF; 173 174 ba_size <<= sta->ht_cap.ampdu_factor; 175 ba_size = min_t(int, 63, ba_size); 176 if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) 177 ba_size = 0; 178 txwi->ack_ctl |= FIELD_PREP(MT_TXWI_ACK_CTL_BA_WINDOW, ba_size); 179 180 txwi->flags = 181 cpu_to_le16(MT_TXWI_FLAGS_AMPDU | 182 FIELD_PREP(MT_TXWI_FLAGS_MPDU_DENSITY, 183 sta->ht_cap.ampdu_density)); 184 if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) 185 txwi->flags = 0; 186 } 187 188 txwi->wcid = wcid->idx; 189 190 is_probe = !!(info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE); 191 pkt_id = mt7601u_tx_pktid_enc(dev, rate_ctl & 0x7, is_probe); 192 pkt_len |= FIELD_PREP(MT_TXWI_LEN_PKTID, pkt_id); 193 txwi->len_ctl = cpu_to_le16(pkt_len); 194 195 return txwi; 196 } 197 198 void mt7601u_tx(struct ieee80211_hw *hw, struct ieee80211_tx_control *control, 199 struct sk_buff *skb) 200 { 201 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb); 202 struct mt7601u_dev *dev = hw->priv; 203 struct ieee80211_vif *vif = info->control.vif; 204 struct ieee80211_sta *sta = control->sta; 205 struct mt76_sta *msta = NULL; 206 struct mt76_wcid *wcid = dev->mon_wcid; 207 struct mt76_txwi *txwi; 208 int pkt_len = skb->len; 209 int hw_q = skb2q(skb); 210 211 BUILD_BUG_ON(ARRAY_SIZE(info->status.status_driver_data) < 1); 212 info->status.status_driver_data[0] = (void *)(unsigned long)pkt_len; 213 214 if (mt7601u_skb_rooms(dev, skb) || mt76_insert_hdr_pad(skb)) { 215 ieee80211_free_txskb(dev->hw, skb); 216 return; 217 } 218 219 if (sta) { 220 msta = (struct mt76_sta *) sta->drv_priv; 221 wcid = &msta->wcid; 222 } else if (vif) { 223 struct mt76_vif *mvif = (struct mt76_vif *)vif->drv_priv; 224 225 wcid = &mvif->group_wcid; 226 } 227 228 txwi = mt7601u_push_txwi(dev, skb, sta, wcid, pkt_len); 229 230 if (mt7601u_dma_enqueue_tx(dev, skb, wcid, hw_q)) 231 return; 232 233 trace_mt_tx(dev, skb, msta, txwi); 234 } 235 236 void mt7601u_tx_stat(struct work_struct *work) 237 { 238 struct mt7601u_dev *dev = container_of(work, struct mt7601u_dev, 239 stat_work.work); 240 struct mt76_tx_status stat; 241 unsigned long flags; 242 int cleaned = 0; 243 244 while (!test_bit(MT7601U_STATE_REMOVED, &dev->state)) { 245 stat = mt7601u_mac_fetch_tx_status(dev); 246 if (!stat.valid) 247 break; 248 249 mt7601u_tx_pktid_dec(dev, &stat); 250 mt76_send_tx_status(dev, &stat); 251 252 cleaned++; 253 } 254 trace_mt_tx_status_cleaned(dev, cleaned); 255 256 spin_lock_irqsave(&dev->tx_lock, flags); 257 if (cleaned) 258 queue_delayed_work(dev->stat_wq, &dev->stat_work, 259 msecs_to_jiffies(10)); 260 else if (test_and_clear_bit(MT7601U_STATE_MORE_STATS, &dev->state)) 261 queue_delayed_work(dev->stat_wq, &dev->stat_work, 262 msecs_to_jiffies(20)); 263 else 264 clear_bit(MT7601U_STATE_READING_STATS, &dev->state); 265 spin_unlock_irqrestore(&dev->tx_lock, flags); 266 } 267 268 int mt7601u_conf_tx(struct ieee80211_hw *hw, struct ieee80211_vif *vif, 269 u16 queue, const struct ieee80211_tx_queue_params *params) 270 { 271 struct mt7601u_dev *dev = hw->priv; 272 u8 cw_min = 5, cw_max = 10, hw_q = q2hwq(queue); 273 u32 val; 274 275 /* TODO: should we do funny things with the parameters? 276 * See what mt7601u_set_default_edca() used to do in init.c. 277 */ 278 279 if (params->cw_min) 280 cw_min = fls(params->cw_min); 281 if (params->cw_max) 282 cw_max = fls(params->cw_max); 283 284 WARN_ON(params->txop > 0xff); 285 WARN_ON(params->aifs > 0xf); 286 WARN_ON(cw_min > 0xf); 287 WARN_ON(cw_max > 0xf); 288 289 val = FIELD_PREP(MT_EDCA_CFG_AIFSN, params->aifs) | 290 FIELD_PREP(MT_EDCA_CFG_CWMIN, cw_min) | 291 FIELD_PREP(MT_EDCA_CFG_CWMAX, cw_max); 292 /* TODO: based on user-controlled EnableTxBurst var vendor drv sets 293 * a really long txop on AC0 (see connect.c:2009) but only on 294 * connect? When not connected should be 0. 295 */ 296 if (!hw_q) 297 val |= 0x60; 298 else 299 val |= FIELD_PREP(MT_EDCA_CFG_TXOP, params->txop); 300 mt76_wr(dev, MT_EDCA_CFG_AC(hw_q), val); 301 302 val = mt76_rr(dev, MT_WMM_TXOP(hw_q)); 303 val &= ~(MT_WMM_TXOP_MASK << MT_WMM_TXOP_SHIFT(hw_q)); 304 val |= params->txop << MT_WMM_TXOP_SHIFT(hw_q); 305 mt76_wr(dev, MT_WMM_TXOP(hw_q), val); 306 307 val = mt76_rr(dev, MT_WMM_AIFSN); 308 val &= ~(MT_WMM_AIFSN_MASK << MT_WMM_AIFSN_SHIFT(hw_q)); 309 val |= params->aifs << MT_WMM_AIFSN_SHIFT(hw_q); 310 mt76_wr(dev, MT_WMM_AIFSN, val); 311 312 val = mt76_rr(dev, MT_WMM_CWMIN); 313 val &= ~(MT_WMM_CWMIN_MASK << MT_WMM_CWMIN_SHIFT(hw_q)); 314 val |= cw_min << MT_WMM_CWMIN_SHIFT(hw_q); 315 mt76_wr(dev, MT_WMM_CWMIN, val); 316 317 val = mt76_rr(dev, MT_WMM_CWMAX); 318 val &= ~(MT_WMM_CWMAX_MASK << MT_WMM_CWMAX_SHIFT(hw_q)); 319 val |= cw_max << MT_WMM_CWMAX_SHIFT(hw_q); 320 mt76_wr(dev, MT_WMM_CWMAX, val); 321 322 return 0; 323 } 324