1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (C) 2014 Felix Fietkau <nbd@openwrt.org>
4 * Copyright (C) 2015 Jakub Kicinski <kubakici@wp.pl>
5 */
6
7#include "mt7601u.h"
8#include "trace.h"
9
10enum mt76_txq_id {
11 MT_TXQ_VO = IEEE80211_AC_VO,
12 MT_TXQ_VI = IEEE80211_AC_VI,
13 MT_TXQ_BE = IEEE80211_AC_BE,
14 MT_TXQ_BK = IEEE80211_AC_BK,
15 MT_TXQ_PSD,
16 MT_TXQ_MCU,
17 __MT_TXQ_MAX
18};
19
20/* Hardware uses mirrored order of queues with Q0 having the highest priority */
21static u8 q2hwq(u8 q)
22{
23 return q ^ 0x3;
24}
25
26/* Take mac80211 Q id from the skb and translate it to hardware Q id */
27static u8 skb2q(struct sk_buff *skb)
28{
29 int qid = skb_get_queue_mapping(skb);
30
31 if (WARN_ON(qid >= MT_TXQ_PSD)) {
32 qid = MT_TXQ_BE;
33 skb_set_queue_mapping(skb, queue_mapping: qid);
34 }
35
36 return q2hwq(q: qid);
37}
38
39/* Note: TX retry reporting is a bit broken.
40 * Retries are reported only once per AMPDU and often come a frame early
41 * i.e. they are reported in the last status preceding the AMPDU. Apart
42 * from the fact that it's hard to know the length of the AMPDU (which is
43 * required to know to how many consecutive frames retries should be
44 * applied), if status comes early on full FIFO it gets lost and retries
45 * of the whole AMPDU become invisible.
46 * As a work-around encode the desired rate in PKT_ID of TX descriptor
47 * and based on that guess the retries (every rate is tried once).
48 * Only downside here is that for MCS0 we have to rely solely on
49 * transmission failures as no retries can ever be reported.
50 * Not having to read EXT_FIFO has a nice effect of doubling the number
51 * of reports which can be fetched.
52 * Also the vendor driver never uses the EXT_FIFO register so it may be
53 * undertested.
54 */
55static u8 mt7601u_tx_pktid_enc(struct mt7601u_dev *dev, u8 rate, bool is_probe)
56{
57 u8 encoded = (rate + 1) + is_probe * 8;
58
59 /* Because PKT_ID 0 disables status reporting only 15 values are
60 * available but 16 are needed (8 MCS * 2 for encoding is_probe)
61 * - we need to cram together two rates. MCS0 and MCS7 with is_probe
62 * share PKT_ID 9.
63 */
64 if (is_probe && rate == 7)
65 return encoded - 7;
66
67 return encoded;
68}
69
70static void
71mt7601u_tx_pktid_dec(struct mt7601u_dev *dev, struct mt76_tx_status *stat)
72{
73 u8 req_rate = stat->pktid;
74 u8 eff_rate = stat->rate & 0x7;
75
76 req_rate -= 1;
77
78 if (req_rate > 7) {
79 stat->is_probe = true;
80 req_rate -= 8;
81
82 /* Decide between MCS0 and MCS7 which share pktid 9 */
83 if (!req_rate && eff_rate)
84 req_rate = 7;
85 }
86
87 stat->retry = req_rate - eff_rate;
88}
89
90static void mt7601u_tx_skb_remove_dma_overhead(struct sk_buff *skb,
91 struct ieee80211_tx_info *info)
92{
93 int pkt_len = (unsigned long)info->status.status_driver_data[0];
94
95 skb_pull(skb, len: sizeof(struct mt76_txwi) + 4);
96 if (ieee80211_get_hdrlen_from_skb(skb) % 4)
97 mt76_remove_hdr_pad(skb);
98
99 skb_trim(skb, len: pkt_len);
100}
101
102void mt7601u_tx_status(struct mt7601u_dev *dev, struct sk_buff *skb)
103{
104 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
105
106 mt7601u_tx_skb_remove_dma_overhead(skb, info);
107
108 ieee80211_tx_info_clear_status(info);
109 info->status.rates[0].idx = -1;
110 info->flags |= IEEE80211_TX_STAT_ACK;
111
112 spin_lock_bh(lock: &dev->mac_lock);
113 ieee80211_tx_status_skb(hw: dev->hw, skb);
114 spin_unlock_bh(lock: &dev->mac_lock);
115}
116
117static int mt7601u_skb_rooms(struct mt7601u_dev *dev, struct sk_buff *skb)
118{
119 int hdr_len = ieee80211_get_hdrlen_from_skb(skb);
120 u32 need_head;
121
122 need_head = sizeof(struct mt76_txwi) + 4;
123 if (hdr_len % 4)
124 need_head += 2;
125
126 return skb_cow(skb, headroom: need_head);
127}
128
129static struct mt76_txwi *
130mt7601u_push_txwi(struct mt7601u_dev *dev, struct sk_buff *skb,
131 struct ieee80211_sta *sta, struct mt76_wcid *wcid,
132 int pkt_len)
133{
134 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
135 struct ieee80211_tx_rate *rate = &info->control.rates[0];
136 struct mt76_txwi *txwi;
137 unsigned long flags;
138 bool is_probe;
139 u32 pkt_id;
140 u16 rate_ctl;
141 u8 nss;
142
143 txwi = skb_push(skb, len: sizeof(struct mt76_txwi));
144 memset(txwi, 0, sizeof(*txwi));
145
146 if (!wcid->tx_rate_set)
147 ieee80211_get_tx_rates(vif: info->control.vif, sta, skb,
148 dest: info->control.rates, max_rates: 1);
149
150 spin_lock_irqsave(&dev->lock, flags);
151 if (rate->idx < 0 || !rate->count)
152 rate_ctl = wcid->tx_rate;
153 else
154 rate_ctl = mt76_mac_tx_rate_val(dev, rate, nss_val: &nss);
155 spin_unlock_irqrestore(lock: &dev->lock, flags);
156 txwi->rate_ctl = cpu_to_le16(rate_ctl);
157
158 if (!(info->flags & IEEE80211_TX_CTL_NO_ACK))
159 txwi->ack_ctl |= MT_TXWI_ACK_CTL_REQ;
160 if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ)
161 txwi->ack_ctl |= MT_TXWI_ACK_CTL_NSEQ;
162
163 if ((info->flags & IEEE80211_TX_CTL_AMPDU) && sta) {
164 u8 ba_size = IEEE80211_MIN_AMPDU_BUF;
165
166 ba_size <<= sta->deflink.ht_cap.ampdu_factor;
167 ba_size = min_t(int, 63, ba_size);
168 if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE)
169 ba_size = 0;
170 txwi->ack_ctl |= FIELD_PREP(MT_TXWI_ACK_CTL_BA_WINDOW, ba_size);
171
172 txwi->flags =
173 cpu_to_le16(MT_TXWI_FLAGS_AMPDU |
174 FIELD_PREP(MT_TXWI_FLAGS_MPDU_DENSITY,
175 sta->deflink.ht_cap.ampdu_density));
176 if (info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE)
177 txwi->flags = 0;
178 }
179
180 txwi->wcid = wcid->idx;
181
182 is_probe = !!(info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE);
183 pkt_id = mt7601u_tx_pktid_enc(dev, rate: rate_ctl & 0x7, is_probe);
184 pkt_len |= FIELD_PREP(MT_TXWI_LEN_PKTID, pkt_id);
185 txwi->len_ctl = cpu_to_le16(pkt_len);
186
187 return txwi;
188}
189
190void mt7601u_tx(struct ieee80211_hw *hw, struct ieee80211_tx_control *control,
191 struct sk_buff *skb)
192{
193 struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
194 struct mt7601u_dev *dev = hw->priv;
195 struct ieee80211_vif *vif = info->control.vif;
196 struct ieee80211_sta *sta = control->sta;
197 struct mt76_sta *msta = NULL;
198 struct mt76_wcid *wcid = dev->mon_wcid;
199 struct mt76_txwi *txwi;
200 int pkt_len = skb->len;
201 int hw_q = skb2q(skb);
202
203 BUILD_BUG_ON(ARRAY_SIZE(info->status.status_driver_data) < 1);
204 info->status.status_driver_data[0] = (void *)(unsigned long)pkt_len;
205
206 if (mt7601u_skb_rooms(dev, skb) || mt76_insert_hdr_pad(skb)) {
207 ieee80211_free_txskb(hw: dev->hw, skb);
208 return;
209 }
210
211 if (sta) {
212 msta = (struct mt76_sta *) sta->drv_priv;
213 wcid = &msta->wcid;
214 } else if (vif) {
215 struct mt76_vif *mvif = (struct mt76_vif *)vif->drv_priv;
216
217 wcid = &mvif->group_wcid;
218 }
219
220 txwi = mt7601u_push_txwi(dev, skb, sta, wcid, pkt_len);
221
222 if (mt7601u_dma_enqueue_tx(dev, skb, wcid, hw_q))
223 return;
224
225 trace_mt_tx(dev, skb, sta: msta, h: txwi);
226}
227
228void mt7601u_tx_stat(struct work_struct *work)
229{
230 struct mt7601u_dev *dev = container_of(work, struct mt7601u_dev,
231 stat_work.work);
232 struct mt76_tx_status stat;
233 unsigned long flags;
234 int cleaned = 0;
235
236 while (!test_bit(MT7601U_STATE_REMOVED, &dev->state)) {
237 stat = mt7601u_mac_fetch_tx_status(dev);
238 if (!stat.valid)
239 break;
240
241 mt7601u_tx_pktid_dec(dev, stat: &stat);
242 mt76_send_tx_status(dev, stat: &stat);
243
244 cleaned++;
245 }
246 trace_mt_tx_status_cleaned(dev, cleaned);
247
248 spin_lock_irqsave(&dev->tx_lock, flags);
249 if (cleaned)
250 queue_delayed_work(wq: dev->stat_wq, dwork: &dev->stat_work,
251 delay: msecs_to_jiffies(m: 10));
252 else if (test_and_clear_bit(nr: MT7601U_STATE_MORE_STATS, addr: &dev->state))
253 queue_delayed_work(wq: dev->stat_wq, dwork: &dev->stat_work,
254 delay: msecs_to_jiffies(m: 20));
255 else
256 clear_bit(nr: MT7601U_STATE_READING_STATS, addr: &dev->state);
257 spin_unlock_irqrestore(lock: &dev->tx_lock, flags);
258}
259
260int mt7601u_conf_tx(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
261 unsigned int link_id, u16 queue,
262 const struct ieee80211_tx_queue_params *params)
263{
264 struct mt7601u_dev *dev = hw->priv;
265 u8 cw_min = 5, cw_max = 10, hw_q = q2hwq(q: queue);
266 u32 val;
267
268 /* TODO: should we do funny things with the parameters?
269 * See what mt7601u_set_default_edca() used to do in init.c.
270 */
271
272 if (params->cw_min)
273 cw_min = fls(x: params->cw_min);
274 if (params->cw_max)
275 cw_max = fls(x: params->cw_max);
276
277 WARN_ON(params->txop > 0xff);
278 WARN_ON(params->aifs > 0xf);
279 WARN_ON(cw_min > 0xf);
280 WARN_ON(cw_max > 0xf);
281
282 val = FIELD_PREP(MT_EDCA_CFG_AIFSN, params->aifs) |
283 FIELD_PREP(MT_EDCA_CFG_CWMIN, cw_min) |
284 FIELD_PREP(MT_EDCA_CFG_CWMAX, cw_max);
285 /* TODO: based on user-controlled EnableTxBurst var vendor drv sets
286 * a really long txop on AC0 (see connect.c:2009) but only on
287 * connect? When not connected should be 0.
288 */
289 if (!hw_q)
290 val |= 0x60;
291 else
292 val |= FIELD_PREP(MT_EDCA_CFG_TXOP, params->txop);
293 mt76_wr(dev, MT_EDCA_CFG_AC(hw_q), val);
294
295 val = mt76_rr(dev, MT_WMM_TXOP(hw_q));
296 val &= ~(MT_WMM_TXOP_MASK << MT_WMM_TXOP_SHIFT(hw_q));
297 val |= params->txop << MT_WMM_TXOP_SHIFT(hw_q);
298 mt76_wr(dev, MT_WMM_TXOP(hw_q), val);
299
300 val = mt76_rr(dev, MT_WMM_AIFSN);
301 val &= ~(MT_WMM_AIFSN_MASK << MT_WMM_AIFSN_SHIFT(hw_q));
302 val |= params->aifs << MT_WMM_AIFSN_SHIFT(hw_q);
303 mt76_wr(dev, MT_WMM_AIFSN, val);
304
305 val = mt76_rr(dev, MT_WMM_CWMIN);
306 val &= ~(MT_WMM_CWMIN_MASK << MT_WMM_CWMIN_SHIFT(hw_q));
307 val |= cw_min << MT_WMM_CWMIN_SHIFT(hw_q);
308 mt76_wr(dev, MT_WMM_CWMIN, val);
309
310 val = mt76_rr(dev, MT_WMM_CWMAX);
311 val &= ~(MT_WMM_CWMAX_MASK << MT_WMM_CWMAX_SHIFT(hw_q));
312 val |= cw_max << MT_WMM_CWMAX_SHIFT(hw_q);
313 mt76_wr(dev, MT_WMM_CWMAX, val);
314
315 return 0;
316}
317

source code of linux/drivers/net/wireless/mediatek/mt7601u/tx.c