xref: /linux/drivers/net/wireless/ath/ath9k/xmit.c (revision b43ab901d671e3e3cad425ea5e9a3c74e266dcdd)
1 /*
2  * Copyright (c) 2008-2011 Atheros Communications Inc.
3  *
4  * Permission to use, copy, modify, and/or distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <linux/dma-mapping.h>
18 #include "ath9k.h"
19 #include "ar9003_mac.h"
20 
21 #define BITS_PER_BYTE           8
22 #define OFDM_PLCP_BITS          22
23 #define HT_RC_2_STREAMS(_rc)    ((((_rc) & 0x78) >> 3) + 1)
24 #define L_STF                   8
25 #define L_LTF                   8
26 #define L_SIG                   4
27 #define HT_SIG                  8
28 #define HT_STF                  4
29 #define HT_LTF(_ns)             (4 * (_ns))
30 #define SYMBOL_TIME(_ns)        ((_ns) << 2) /* ns * 4 us */
31 #define SYMBOL_TIME_HALFGI(_ns) (((_ns) * 18 + 4) / 5)  /* ns * 3.6 us */
32 #define NUM_SYMBOLS_PER_USEC(_usec) (_usec >> 2)
33 #define NUM_SYMBOLS_PER_USEC_HALFGI(_usec) (((_usec*5)-4)/18)
34 
35 
36 static u16 bits_per_symbol[][2] = {
37 	/* 20MHz 40MHz */
38 	{    26,   54 },     /*  0: BPSK */
39 	{    52,  108 },     /*  1: QPSK 1/2 */
40 	{    78,  162 },     /*  2: QPSK 3/4 */
41 	{   104,  216 },     /*  3: 16-QAM 1/2 */
42 	{   156,  324 },     /*  4: 16-QAM 3/4 */
43 	{   208,  432 },     /*  5: 64-QAM 2/3 */
44 	{   234,  486 },     /*  6: 64-QAM 3/4 */
45 	{   260,  540 },     /*  7: 64-QAM 5/6 */
46 };
47 
48 #define IS_HT_RATE(_rate)     ((_rate) & 0x80)
49 
50 static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
51 			       struct ath_atx_tid *tid, struct sk_buff *skb);
52 static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
53 			    int tx_flags, struct ath_txq *txq);
54 static void ath_tx_complete_buf(struct ath_softc *sc, struct ath_buf *bf,
55 				struct ath_txq *txq, struct list_head *bf_q,
56 				struct ath_tx_status *ts, int txok);
57 static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq,
58 			     struct list_head *head, bool internal);
59 static void ath_tx_rc_status(struct ath_softc *sc, struct ath_buf *bf,
60 			     struct ath_tx_status *ts, int nframes, int nbad,
61 			     int txok);
62 static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
63 			      int seqno);
64 static struct ath_buf *ath_tx_setup_buffer(struct ath_softc *sc,
65 					   struct ath_txq *txq,
66 					   struct ath_atx_tid *tid,
67 					   struct sk_buff *skb);
68 
69 enum {
70 	MCS_HT20,
71 	MCS_HT20_SGI,
72 	MCS_HT40,
73 	MCS_HT40_SGI,
74 };
75 
76 static int ath_max_4ms_framelen[4][32] = {
77 	[MCS_HT20] = {
78 		3212,  6432,  9648,  12864,  19300,  25736,  28952,  32172,
79 		6424,  12852, 19280, 25708,  38568,  51424,  57852,  64280,
80 		9628,  19260, 28896, 38528,  57792,  65532,  65532,  65532,
81 		12828, 25656, 38488, 51320,  65532,  65532,  65532,  65532,
82 	},
83 	[MCS_HT20_SGI] = {
84 		3572,  7144,  10720,  14296,  21444,  28596,  32172,  35744,
85 		7140,  14284, 21428,  28568,  42856,  57144,  64288,  65532,
86 		10700, 21408, 32112,  42816,  64228,  65532,  65532,  65532,
87 		14256, 28516, 42780,  57040,  65532,  65532,  65532,  65532,
88 	},
89 	[MCS_HT40] = {
90 		6680,  13360,  20044,  26724,  40092,  53456,  60140,  65532,
91 		13348, 26700,  40052,  53400,  65532,  65532,  65532,  65532,
92 		20004, 40008,  60016,  65532,  65532,  65532,  65532,  65532,
93 		26644, 53292,  65532,  65532,  65532,  65532,  65532,  65532,
94 	},
95 	[MCS_HT40_SGI] = {
96 		7420,  14844,  22272,  29696,  44544,  59396,  65532,  65532,
97 		14832, 29668,  44504,  59340,  65532,  65532,  65532,  65532,
98 		22232, 44464,  65532,  65532,  65532,  65532,  65532,  65532,
99 		29616, 59232,  65532,  65532,  65532,  65532,  65532,  65532,
100 	}
101 };
102 
103 /*********************/
104 /* Aggregation logic */
105 /*********************/
106 
107 static void ath_txq_lock(struct ath_softc *sc, struct ath_txq *txq)
108 	__acquires(&txq->axq_lock)
109 {
110 	spin_lock_bh(&txq->axq_lock);
111 }
112 
113 static void ath_txq_unlock(struct ath_softc *sc, struct ath_txq *txq)
114 	__releases(&txq->axq_lock)
115 {
116 	spin_unlock_bh(&txq->axq_lock);
117 }
118 
119 static void ath_txq_unlock_complete(struct ath_softc *sc, struct ath_txq *txq)
120 	__releases(&txq->axq_lock)
121 {
122 	struct sk_buff_head q;
123 	struct sk_buff *skb;
124 
125 	__skb_queue_head_init(&q);
126 	skb_queue_splice_init(&txq->complete_q, &q);
127 	spin_unlock_bh(&txq->axq_lock);
128 
129 	while ((skb = __skb_dequeue(&q)))
130 		ieee80211_tx_status(sc->hw, skb);
131 }
132 
133 static void ath_tx_queue_tid(struct ath_txq *txq, struct ath_atx_tid *tid)
134 {
135 	struct ath_atx_ac *ac = tid->ac;
136 
137 	if (tid->paused)
138 		return;
139 
140 	if (tid->sched)
141 		return;
142 
143 	tid->sched = true;
144 	list_add_tail(&tid->list, &ac->tid_q);
145 
146 	if (ac->sched)
147 		return;
148 
149 	ac->sched = true;
150 	list_add_tail(&ac->list, &txq->axq_acq);
151 }
152 
153 static void ath_tx_resume_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
154 {
155 	struct ath_txq *txq = tid->ac->txq;
156 
157 	WARN_ON(!tid->paused);
158 
159 	ath_txq_lock(sc, txq);
160 	tid->paused = false;
161 
162 	if (skb_queue_empty(&tid->buf_q))
163 		goto unlock;
164 
165 	ath_tx_queue_tid(txq, tid);
166 	ath_txq_schedule(sc, txq);
167 unlock:
168 	ath_txq_unlock_complete(sc, txq);
169 }
170 
171 static struct ath_frame_info *get_frame_info(struct sk_buff *skb)
172 {
173 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
174 	BUILD_BUG_ON(sizeof(struct ath_frame_info) >
175 		     sizeof(tx_info->rate_driver_data));
176 	return (struct ath_frame_info *) &tx_info->rate_driver_data[0];
177 }
178 
179 static void ath_send_bar(struct ath_atx_tid *tid, u16 seqno)
180 {
181 	ieee80211_send_bar(tid->an->vif, tid->an->sta->addr, tid->tidno,
182 			   seqno << IEEE80211_SEQ_SEQ_SHIFT);
183 }
184 
185 static void ath_tx_flush_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
186 {
187 	struct ath_txq *txq = tid->ac->txq;
188 	struct sk_buff *skb;
189 	struct ath_buf *bf;
190 	struct list_head bf_head;
191 	struct ath_tx_status ts;
192 	struct ath_frame_info *fi;
193 	bool sendbar = false;
194 
195 	INIT_LIST_HEAD(&bf_head);
196 
197 	memset(&ts, 0, sizeof(ts));
198 
199 	while ((skb = __skb_dequeue(&tid->buf_q))) {
200 		fi = get_frame_info(skb);
201 		bf = fi->bf;
202 
203 		if (bf && fi->retries) {
204 			list_add_tail(&bf->list, &bf_head);
205 			ath_tx_update_baw(sc, tid, bf->bf_state.seqno);
206 			ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0);
207 			sendbar = true;
208 		} else {
209 			ath_tx_send_normal(sc, txq, NULL, skb);
210 		}
211 	}
212 
213 	if (tid->baw_head == tid->baw_tail) {
214 		tid->state &= ~AGGR_ADDBA_COMPLETE;
215 		tid->state &= ~AGGR_CLEANUP;
216 	}
217 
218 	if (sendbar) {
219 		ath_txq_unlock(sc, txq);
220 		ath_send_bar(tid, tid->seq_start);
221 		ath_txq_lock(sc, txq);
222 	}
223 }
224 
225 static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
226 			      int seqno)
227 {
228 	int index, cindex;
229 
230 	index  = ATH_BA_INDEX(tid->seq_start, seqno);
231 	cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
232 
233 	__clear_bit(cindex, tid->tx_buf);
234 
235 	while (tid->baw_head != tid->baw_tail && !test_bit(tid->baw_head, tid->tx_buf)) {
236 		INCR(tid->seq_start, IEEE80211_SEQ_MAX);
237 		INCR(tid->baw_head, ATH_TID_MAX_BUFS);
238 		if (tid->bar_index >= 0)
239 			tid->bar_index--;
240 	}
241 }
242 
243 static void ath_tx_addto_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
244 			     u16 seqno)
245 {
246 	int index, cindex;
247 
248 	index  = ATH_BA_INDEX(tid->seq_start, seqno);
249 	cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
250 	__set_bit(cindex, tid->tx_buf);
251 
252 	if (index >= ((tid->baw_tail - tid->baw_head) &
253 		(ATH_TID_MAX_BUFS - 1))) {
254 		tid->baw_tail = cindex;
255 		INCR(tid->baw_tail, ATH_TID_MAX_BUFS);
256 	}
257 }
258 
259 /*
260  * TODO: For frame(s) that are in the retry state, we will reuse the
261  * sequence number(s) without setting the retry bit. The
262  * alternative is to give up on these and BAR the receiver's window
263  * forward.
264  */
265 static void ath_tid_drain(struct ath_softc *sc, struct ath_txq *txq,
266 			  struct ath_atx_tid *tid)
267 
268 {
269 	struct sk_buff *skb;
270 	struct ath_buf *bf;
271 	struct list_head bf_head;
272 	struct ath_tx_status ts;
273 	struct ath_frame_info *fi;
274 
275 	memset(&ts, 0, sizeof(ts));
276 	INIT_LIST_HEAD(&bf_head);
277 
278 	while ((skb = __skb_dequeue(&tid->buf_q))) {
279 		fi = get_frame_info(skb);
280 		bf = fi->bf;
281 
282 		if (!bf) {
283 			ath_tx_complete(sc, skb, ATH_TX_ERROR, txq);
284 			continue;
285 		}
286 
287 		list_add_tail(&bf->list, &bf_head);
288 
289 		if (fi->retries)
290 			ath_tx_update_baw(sc, tid, bf->bf_state.seqno);
291 
292 		ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0);
293 	}
294 
295 	tid->seq_next = tid->seq_start;
296 	tid->baw_tail = tid->baw_head;
297 	tid->bar_index = -1;
298 }
299 
300 static void ath_tx_set_retry(struct ath_softc *sc, struct ath_txq *txq,
301 			     struct sk_buff *skb, int count)
302 {
303 	struct ath_frame_info *fi = get_frame_info(skb);
304 	struct ath_buf *bf = fi->bf;
305 	struct ieee80211_hdr *hdr;
306 	int prev = fi->retries;
307 
308 	TX_STAT_INC(txq->axq_qnum, a_retries);
309 	fi->retries += count;
310 
311 	if (prev > 0)
312 		return;
313 
314 	hdr = (struct ieee80211_hdr *)skb->data;
315 	hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_RETRY);
316 	dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
317 		sizeof(*hdr), DMA_TO_DEVICE);
318 }
319 
320 static struct ath_buf *ath_tx_get_buffer(struct ath_softc *sc)
321 {
322 	struct ath_buf *bf = NULL;
323 
324 	spin_lock_bh(&sc->tx.txbuflock);
325 
326 	if (unlikely(list_empty(&sc->tx.txbuf))) {
327 		spin_unlock_bh(&sc->tx.txbuflock);
328 		return NULL;
329 	}
330 
331 	bf = list_first_entry(&sc->tx.txbuf, struct ath_buf, list);
332 	list_del(&bf->list);
333 
334 	spin_unlock_bh(&sc->tx.txbuflock);
335 
336 	return bf;
337 }
338 
339 static void ath_tx_return_buffer(struct ath_softc *sc, struct ath_buf *bf)
340 {
341 	spin_lock_bh(&sc->tx.txbuflock);
342 	list_add_tail(&bf->list, &sc->tx.txbuf);
343 	spin_unlock_bh(&sc->tx.txbuflock);
344 }
345 
346 static struct ath_buf* ath_clone_txbuf(struct ath_softc *sc, struct ath_buf *bf)
347 {
348 	struct ath_buf *tbf;
349 
350 	tbf = ath_tx_get_buffer(sc);
351 	if (WARN_ON(!tbf))
352 		return NULL;
353 
354 	ATH_TXBUF_RESET(tbf);
355 
356 	tbf->bf_mpdu = bf->bf_mpdu;
357 	tbf->bf_buf_addr = bf->bf_buf_addr;
358 	memcpy(tbf->bf_desc, bf->bf_desc, sc->sc_ah->caps.tx_desc_len);
359 	tbf->bf_state = bf->bf_state;
360 
361 	return tbf;
362 }
363 
364 static void ath_tx_count_frames(struct ath_softc *sc, struct ath_buf *bf,
365 			        struct ath_tx_status *ts, int txok,
366 			        int *nframes, int *nbad)
367 {
368 	struct ath_frame_info *fi;
369 	u16 seq_st = 0;
370 	u32 ba[WME_BA_BMP_SIZE >> 5];
371 	int ba_index;
372 	int isaggr = 0;
373 
374 	*nbad = 0;
375 	*nframes = 0;
376 
377 	isaggr = bf_isaggr(bf);
378 	if (isaggr) {
379 		seq_st = ts->ts_seqnum;
380 		memcpy(ba, &ts->ba_low, WME_BA_BMP_SIZE >> 3);
381 	}
382 
383 	while (bf) {
384 		fi = get_frame_info(bf->bf_mpdu);
385 		ba_index = ATH_BA_INDEX(seq_st, bf->bf_state.seqno);
386 
387 		(*nframes)++;
388 		if (!txok || (isaggr && !ATH_BA_ISSET(ba, ba_index)))
389 			(*nbad)++;
390 
391 		bf = bf->bf_next;
392 	}
393 }
394 
395 
396 static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq,
397 				 struct ath_buf *bf, struct list_head *bf_q,
398 				 struct ath_tx_status *ts, int txok, bool retry)
399 {
400 	struct ath_node *an = NULL;
401 	struct sk_buff *skb;
402 	struct ieee80211_sta *sta;
403 	struct ieee80211_hw *hw = sc->hw;
404 	struct ieee80211_hdr *hdr;
405 	struct ieee80211_tx_info *tx_info;
406 	struct ath_atx_tid *tid = NULL;
407 	struct ath_buf *bf_next, *bf_last = bf->bf_lastbf;
408 	struct list_head bf_head;
409 	struct sk_buff_head bf_pending;
410 	u16 seq_st = 0, acked_cnt = 0, txfail_cnt = 0, seq_first;
411 	u32 ba[WME_BA_BMP_SIZE >> 5];
412 	int isaggr, txfail, txpending, sendbar = 0, needreset = 0, nbad = 0;
413 	bool rc_update = true;
414 	struct ieee80211_tx_rate rates[4];
415 	struct ath_frame_info *fi;
416 	int nframes;
417 	u8 tidno;
418 	bool flush = !!(ts->ts_status & ATH9K_TX_FLUSH);
419 	int i, retries;
420 	int bar_index = -1;
421 
422 	skb = bf->bf_mpdu;
423 	hdr = (struct ieee80211_hdr *)skb->data;
424 
425 	tx_info = IEEE80211_SKB_CB(skb);
426 
427 	memcpy(rates, tx_info->control.rates, sizeof(rates));
428 
429 	retries = ts->ts_longretry + 1;
430 	for (i = 0; i < ts->ts_rateindex; i++)
431 		retries += rates[i].count;
432 
433 	rcu_read_lock();
434 
435 	sta = ieee80211_find_sta_by_ifaddr(hw, hdr->addr1, hdr->addr2);
436 	if (!sta) {
437 		rcu_read_unlock();
438 
439 		INIT_LIST_HEAD(&bf_head);
440 		while (bf) {
441 			bf_next = bf->bf_next;
442 
443 			if (!bf->bf_stale || bf_next != NULL)
444 				list_move_tail(&bf->list, &bf_head);
445 
446 			ath_tx_complete_buf(sc, bf, txq, &bf_head, ts, 0);
447 
448 			bf = bf_next;
449 		}
450 		return;
451 	}
452 
453 	an = (struct ath_node *)sta->drv_priv;
454 	tidno = ieee80211_get_qos_ctl(hdr)[0] & IEEE80211_QOS_CTL_TID_MASK;
455 	tid = ATH_AN_2_TID(an, tidno);
456 	seq_first = tid->seq_start;
457 
458 	/*
459 	 * The hardware occasionally sends a tx status for the wrong TID.
460 	 * In this case, the BA status cannot be considered valid and all
461 	 * subframes need to be retransmitted
462 	 */
463 	if (tidno != ts->tid)
464 		txok = false;
465 
466 	isaggr = bf_isaggr(bf);
467 	memset(ba, 0, WME_BA_BMP_SIZE >> 3);
468 
469 	if (isaggr && txok) {
470 		if (ts->ts_flags & ATH9K_TX_BA) {
471 			seq_st = ts->ts_seqnum;
472 			memcpy(ba, &ts->ba_low, WME_BA_BMP_SIZE >> 3);
473 		} else {
474 			/*
475 			 * AR5416 can become deaf/mute when BA
476 			 * issue happens. Chip needs to be reset.
477 			 * But AP code may have sychronization issues
478 			 * when perform internal reset in this routine.
479 			 * Only enable reset in STA mode for now.
480 			 */
481 			if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION)
482 				needreset = 1;
483 		}
484 	}
485 
486 	__skb_queue_head_init(&bf_pending);
487 
488 	ath_tx_count_frames(sc, bf, ts, txok, &nframes, &nbad);
489 	while (bf) {
490 		u16 seqno = bf->bf_state.seqno;
491 
492 		txfail = txpending = sendbar = 0;
493 		bf_next = bf->bf_next;
494 
495 		skb = bf->bf_mpdu;
496 		tx_info = IEEE80211_SKB_CB(skb);
497 		fi = get_frame_info(skb);
498 
499 		if (ATH_BA_ISSET(ba, ATH_BA_INDEX(seq_st, seqno))) {
500 			/* transmit completion, subframe is
501 			 * acked by block ack */
502 			acked_cnt++;
503 		} else if (!isaggr && txok) {
504 			/* transmit completion */
505 			acked_cnt++;
506 		} else if ((tid->state & AGGR_CLEANUP) || !retry) {
507 			/*
508 			 * cleanup in progress, just fail
509 			 * the un-acked sub-frames
510 			 */
511 			txfail = 1;
512 		} else if (flush) {
513 			txpending = 1;
514 		} else if (fi->retries < ATH_MAX_SW_RETRIES) {
515 			if (txok || !an->sleeping)
516 				ath_tx_set_retry(sc, txq, bf->bf_mpdu,
517 						 retries);
518 
519 			txpending = 1;
520 		} else {
521 			txfail = 1;
522 			txfail_cnt++;
523 			bar_index = max_t(int, bar_index,
524 				ATH_BA_INDEX(seq_first, seqno));
525 		}
526 
527 		/*
528 		 * Make sure the last desc is reclaimed if it
529 		 * not a holding desc.
530 		 */
531 		INIT_LIST_HEAD(&bf_head);
532 		if ((sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) ||
533 		    bf_next != NULL || !bf_last->bf_stale)
534 			list_move_tail(&bf->list, &bf_head);
535 
536 		if (!txpending || (tid->state & AGGR_CLEANUP)) {
537 			/*
538 			 * complete the acked-ones/xretried ones; update
539 			 * block-ack window
540 			 */
541 			ath_tx_update_baw(sc, tid, seqno);
542 
543 			if (rc_update && (acked_cnt == 1 || txfail_cnt == 1)) {
544 				memcpy(tx_info->control.rates, rates, sizeof(rates));
545 				ath_tx_rc_status(sc, bf, ts, nframes, nbad, txok);
546 				rc_update = false;
547 			}
548 
549 			ath_tx_complete_buf(sc, bf, txq, &bf_head, ts,
550 				!txfail);
551 		} else {
552 			/* retry the un-acked ones */
553 			if (!(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) &&
554 			    bf->bf_next == NULL && bf_last->bf_stale) {
555 				struct ath_buf *tbf;
556 
557 				tbf = ath_clone_txbuf(sc, bf_last);
558 				/*
559 				 * Update tx baw and complete the
560 				 * frame with failed status if we
561 				 * run out of tx buf.
562 				 */
563 				if (!tbf) {
564 					ath_tx_update_baw(sc, tid, seqno);
565 
566 					ath_tx_complete_buf(sc, bf, txq,
567 							    &bf_head, ts, 0);
568 					bar_index = max_t(int, bar_index,
569 						ATH_BA_INDEX(seq_first, seqno));
570 					break;
571 				}
572 
573 				fi->bf = tbf;
574 			}
575 
576 			/*
577 			 * Put this buffer to the temporary pending
578 			 * queue to retain ordering
579 			 */
580 			__skb_queue_tail(&bf_pending, skb);
581 		}
582 
583 		bf = bf_next;
584 	}
585 
586 	/* prepend un-acked frames to the beginning of the pending frame queue */
587 	if (!skb_queue_empty(&bf_pending)) {
588 		if (an->sleeping)
589 			ieee80211_sta_set_buffered(sta, tid->tidno, true);
590 
591 		skb_queue_splice(&bf_pending, &tid->buf_q);
592 		if (!an->sleeping) {
593 			ath_tx_queue_tid(txq, tid);
594 
595 			if (ts->ts_status & ATH9K_TXERR_FILT)
596 				tid->ac->clear_ps_filter = true;
597 		}
598 	}
599 
600 	if (bar_index >= 0) {
601 		u16 bar_seq = ATH_BA_INDEX2SEQ(seq_first, bar_index);
602 
603 		if (BAW_WITHIN(tid->seq_start, tid->baw_size, bar_seq))
604 			tid->bar_index = ATH_BA_INDEX(tid->seq_start, bar_seq);
605 
606 		ath_txq_unlock(sc, txq);
607 		ath_send_bar(tid, ATH_BA_INDEX2SEQ(seq_first, bar_index + 1));
608 		ath_txq_lock(sc, txq);
609 	}
610 
611 	if (tid->state & AGGR_CLEANUP)
612 		ath_tx_flush_tid(sc, tid);
613 
614 	rcu_read_unlock();
615 
616 	if (needreset) {
617 		RESET_STAT_INC(sc, RESET_TYPE_TX_ERROR);
618 		ieee80211_queue_work(sc->hw, &sc->hw_reset_work);
619 	}
620 }
621 
622 static bool ath_lookup_legacy(struct ath_buf *bf)
623 {
624 	struct sk_buff *skb;
625 	struct ieee80211_tx_info *tx_info;
626 	struct ieee80211_tx_rate *rates;
627 	int i;
628 
629 	skb = bf->bf_mpdu;
630 	tx_info = IEEE80211_SKB_CB(skb);
631 	rates = tx_info->control.rates;
632 
633 	for (i = 0; i < 4; i++) {
634 		if (!rates[i].count || rates[i].idx < 0)
635 			break;
636 
637 		if (!(rates[i].flags & IEEE80211_TX_RC_MCS))
638 			return true;
639 	}
640 
641 	return false;
642 }
643 
644 static u32 ath_lookup_rate(struct ath_softc *sc, struct ath_buf *bf,
645 			   struct ath_atx_tid *tid)
646 {
647 	struct sk_buff *skb;
648 	struct ieee80211_tx_info *tx_info;
649 	struct ieee80211_tx_rate *rates;
650 	struct ath_mci_profile *mci = &sc->btcoex.mci;
651 	u32 max_4ms_framelen, frmlen;
652 	u16 aggr_limit, legacy = 0;
653 	int i;
654 
655 	skb = bf->bf_mpdu;
656 	tx_info = IEEE80211_SKB_CB(skb);
657 	rates = tx_info->control.rates;
658 
659 	/*
660 	 * Find the lowest frame length among the rate series that will have a
661 	 * 4ms transmit duration.
662 	 * TODO - TXOP limit needs to be considered.
663 	 */
664 	max_4ms_framelen = ATH_AMPDU_LIMIT_MAX;
665 
666 	for (i = 0; i < 4; i++) {
667 		int modeidx;
668 
669 		if (!rates[i].count)
670 			continue;
671 
672 		if (!(rates[i].flags & IEEE80211_TX_RC_MCS)) {
673 			legacy = 1;
674 			break;
675 		}
676 
677 		if (rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
678 			modeidx = MCS_HT40;
679 		else
680 			modeidx = MCS_HT20;
681 
682 		if (rates[i].flags & IEEE80211_TX_RC_SHORT_GI)
683 			modeidx++;
684 
685 		frmlen = ath_max_4ms_framelen[modeidx][rates[i].idx];
686 		max_4ms_framelen = min(max_4ms_framelen, frmlen);
687 	}
688 
689 	/*
690 	 * limit aggregate size by the minimum rate if rate selected is
691 	 * not a probe rate, if rate selected is a probe rate then
692 	 * avoid aggregation of this packet.
693 	 */
694 	if (tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE || legacy)
695 		return 0;
696 
697 	if ((sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_MCI) && mci->aggr_limit)
698 		aggr_limit = (max_4ms_framelen * mci->aggr_limit) >> 4;
699 	else if (sc->sc_flags & SC_OP_BT_PRIORITY_DETECTED)
700 		aggr_limit = min((max_4ms_framelen * 3) / 8,
701 				 (u32)ATH_AMPDU_LIMIT_MAX);
702 	else
703 		aggr_limit = min(max_4ms_framelen,
704 				 (u32)ATH_AMPDU_LIMIT_MAX);
705 
706 	/*
707 	 * h/w can accept aggregates up to 16 bit lengths (65535).
708 	 * The IE, however can hold up to 65536, which shows up here
709 	 * as zero. Ignore 65536 since we  are constrained by hw.
710 	 */
711 	if (tid->an->maxampdu)
712 		aggr_limit = min(aggr_limit, tid->an->maxampdu);
713 
714 	return aggr_limit;
715 }
716 
717 /*
718  * Returns the number of delimiters to be added to
719  * meet the minimum required mpdudensity.
720  */
721 static int ath_compute_num_delims(struct ath_softc *sc, struct ath_atx_tid *tid,
722 				  struct ath_buf *bf, u16 frmlen,
723 				  bool first_subfrm)
724 {
725 #define FIRST_DESC_NDELIMS 60
726 	struct sk_buff *skb = bf->bf_mpdu;
727 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
728 	u32 nsymbits, nsymbols;
729 	u16 minlen;
730 	u8 flags, rix;
731 	int width, streams, half_gi, ndelim, mindelim;
732 	struct ath_frame_info *fi = get_frame_info(bf->bf_mpdu);
733 
734 	/* Select standard number of delimiters based on frame length alone */
735 	ndelim = ATH_AGGR_GET_NDELIM(frmlen);
736 
737 	/*
738 	 * If encryption enabled, hardware requires some more padding between
739 	 * subframes.
740 	 * TODO - this could be improved to be dependent on the rate.
741 	 *      The hardware can keep up at lower rates, but not higher rates
742 	 */
743 	if ((fi->keyix != ATH9K_TXKEYIX_INVALID) &&
744 	    !(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA))
745 		ndelim += ATH_AGGR_ENCRYPTDELIM;
746 
747 	/*
748 	 * Add delimiter when using RTS/CTS with aggregation
749 	 * and non enterprise AR9003 card
750 	 */
751 	if (first_subfrm && !AR_SREV_9580_10_OR_LATER(sc->sc_ah) &&
752 	    (sc->sc_ah->ent_mode & AR_ENT_OTP_MIN_PKT_SIZE_DISABLE))
753 		ndelim = max(ndelim, FIRST_DESC_NDELIMS);
754 
755 	/*
756 	 * Convert desired mpdu density from microeconds to bytes based
757 	 * on highest rate in rate series (i.e. first rate) to determine
758 	 * required minimum length for subframe. Take into account
759 	 * whether high rate is 20 or 40Mhz and half or full GI.
760 	 *
761 	 * If there is no mpdu density restriction, no further calculation
762 	 * is needed.
763 	 */
764 
765 	if (tid->an->mpdudensity == 0)
766 		return ndelim;
767 
768 	rix = tx_info->control.rates[0].idx;
769 	flags = tx_info->control.rates[0].flags;
770 	width = (flags & IEEE80211_TX_RC_40_MHZ_WIDTH) ? 1 : 0;
771 	half_gi = (flags & IEEE80211_TX_RC_SHORT_GI) ? 1 : 0;
772 
773 	if (half_gi)
774 		nsymbols = NUM_SYMBOLS_PER_USEC_HALFGI(tid->an->mpdudensity);
775 	else
776 		nsymbols = NUM_SYMBOLS_PER_USEC(tid->an->mpdudensity);
777 
778 	if (nsymbols == 0)
779 		nsymbols = 1;
780 
781 	streams = HT_RC_2_STREAMS(rix);
782 	nsymbits = bits_per_symbol[rix % 8][width] * streams;
783 	minlen = (nsymbols * nsymbits) / BITS_PER_BYTE;
784 
785 	if (frmlen < minlen) {
786 		mindelim = (minlen - frmlen) / ATH_AGGR_DELIM_SZ;
787 		ndelim = max(mindelim, ndelim);
788 	}
789 
790 	return ndelim;
791 }
792 
793 static enum ATH_AGGR_STATUS ath_tx_form_aggr(struct ath_softc *sc,
794 					     struct ath_txq *txq,
795 					     struct ath_atx_tid *tid,
796 					     struct list_head *bf_q,
797 					     int *aggr_len)
798 {
799 #define PADBYTES(_len) ((4 - ((_len) % 4)) % 4)
800 	struct ath_buf *bf, *bf_first = NULL, *bf_prev = NULL;
801 	int rl = 0, nframes = 0, ndelim, prev_al = 0;
802 	u16 aggr_limit = 0, al = 0, bpad = 0,
803 		al_delta, h_baw = tid->baw_size / 2;
804 	enum ATH_AGGR_STATUS status = ATH_AGGR_DONE;
805 	struct ieee80211_tx_info *tx_info;
806 	struct ath_frame_info *fi;
807 	struct sk_buff *skb;
808 	u16 seqno;
809 
810 	do {
811 		skb = skb_peek(&tid->buf_q);
812 		fi = get_frame_info(skb);
813 		bf = fi->bf;
814 		if (!fi->bf)
815 			bf = ath_tx_setup_buffer(sc, txq, tid, skb);
816 
817 		if (!bf)
818 			continue;
819 
820 		bf->bf_state.bf_type = BUF_AMPDU | BUF_AGGR;
821 		seqno = bf->bf_state.seqno;
822 
823 		/* do not step over block-ack window */
824 		if (!BAW_WITHIN(tid->seq_start, tid->baw_size, seqno)) {
825 			status = ATH_AGGR_BAW_CLOSED;
826 			break;
827 		}
828 
829 		if (tid->bar_index > ATH_BA_INDEX(tid->seq_start, seqno)) {
830 			struct ath_tx_status ts = {};
831 			struct list_head bf_head;
832 
833 			INIT_LIST_HEAD(&bf_head);
834 			list_add(&bf->list, &bf_head);
835 			__skb_unlink(skb, &tid->buf_q);
836 			ath_tx_update_baw(sc, tid, seqno);
837 			ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0);
838 			continue;
839 		}
840 
841 		if (!bf_first)
842 			bf_first = bf;
843 
844 		if (!rl) {
845 			aggr_limit = ath_lookup_rate(sc, bf, tid);
846 			rl = 1;
847 		}
848 
849 		/* do not exceed aggregation limit */
850 		al_delta = ATH_AGGR_DELIM_SZ + fi->framelen;
851 
852 		if (nframes &&
853 		    ((aggr_limit < (al + bpad + al_delta + prev_al)) ||
854 		     ath_lookup_legacy(bf))) {
855 			status = ATH_AGGR_LIMITED;
856 			break;
857 		}
858 
859 		tx_info = IEEE80211_SKB_CB(bf->bf_mpdu);
860 		if (nframes && (tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE))
861 			break;
862 
863 		/* do not exceed subframe limit */
864 		if (nframes >= min((int)h_baw, ATH_AMPDU_SUBFRAME_DEFAULT)) {
865 			status = ATH_AGGR_LIMITED;
866 			break;
867 		}
868 
869 		/* add padding for previous frame to aggregation length */
870 		al += bpad + al_delta;
871 
872 		/*
873 		 * Get the delimiters needed to meet the MPDU
874 		 * density for this node.
875 		 */
876 		ndelim = ath_compute_num_delims(sc, tid, bf_first, fi->framelen,
877 						!nframes);
878 		bpad = PADBYTES(al_delta) + (ndelim << 2);
879 
880 		nframes++;
881 		bf->bf_next = NULL;
882 
883 		/* link buffers of this frame to the aggregate */
884 		if (!fi->retries)
885 			ath_tx_addto_baw(sc, tid, seqno);
886 		bf->bf_state.ndelim = ndelim;
887 
888 		__skb_unlink(skb, &tid->buf_q);
889 		list_add_tail(&bf->list, bf_q);
890 		if (bf_prev)
891 			bf_prev->bf_next = bf;
892 
893 		bf_prev = bf;
894 
895 	} while (!skb_queue_empty(&tid->buf_q));
896 
897 	*aggr_len = al;
898 
899 	return status;
900 #undef PADBYTES
901 }
902 
903 /*
904  * rix - rate index
905  * pktlen - total bytes (delims + data + fcs + pads + pad delims)
906  * width  - 0 for 20 MHz, 1 for 40 MHz
907  * half_gi - to use 4us v/s 3.6 us for symbol time
908  */
909 static u32 ath_pkt_duration(struct ath_softc *sc, u8 rix, int pktlen,
910 			    int width, int half_gi, bool shortPreamble)
911 {
912 	u32 nbits, nsymbits, duration, nsymbols;
913 	int streams;
914 
915 	/* find number of symbols: PLCP + data */
916 	streams = HT_RC_2_STREAMS(rix);
917 	nbits = (pktlen << 3) + OFDM_PLCP_BITS;
918 	nsymbits = bits_per_symbol[rix % 8][width] * streams;
919 	nsymbols = (nbits + nsymbits - 1) / nsymbits;
920 
921 	if (!half_gi)
922 		duration = SYMBOL_TIME(nsymbols);
923 	else
924 		duration = SYMBOL_TIME_HALFGI(nsymbols);
925 
926 	/* addup duration for legacy/ht training and signal fields */
927 	duration += L_STF + L_LTF + L_SIG + HT_SIG + HT_STF + HT_LTF(streams);
928 
929 	return duration;
930 }
931 
932 static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf,
933 			     struct ath_tx_info *info, int len)
934 {
935 	struct ath_hw *ah = sc->sc_ah;
936 	struct sk_buff *skb;
937 	struct ieee80211_tx_info *tx_info;
938 	struct ieee80211_tx_rate *rates;
939 	const struct ieee80211_rate *rate;
940 	struct ieee80211_hdr *hdr;
941 	int i;
942 	u8 rix = 0;
943 
944 	skb = bf->bf_mpdu;
945 	tx_info = IEEE80211_SKB_CB(skb);
946 	rates = tx_info->control.rates;
947 	hdr = (struct ieee80211_hdr *)skb->data;
948 
949 	/* set dur_update_en for l-sig computation except for PS-Poll frames */
950 	info->dur_update = !ieee80211_is_pspoll(hdr->frame_control);
951 
952 	/*
953 	 * We check if Short Preamble is needed for the CTS rate by
954 	 * checking the BSS's global flag.
955 	 * But for the rate series, IEEE80211_TX_RC_USE_SHORT_PREAMBLE is used.
956 	 */
957 	rate = ieee80211_get_rts_cts_rate(sc->hw, tx_info);
958 	info->rtscts_rate = rate->hw_value;
959 	if (sc->sc_flags & SC_OP_PREAMBLE_SHORT)
960 		info->rtscts_rate |= rate->hw_value_short;
961 
962 	for (i = 0; i < 4; i++) {
963 		bool is_40, is_sgi, is_sp;
964 		int phy;
965 
966 		if (!rates[i].count || (rates[i].idx < 0))
967 			continue;
968 
969 		rix = rates[i].idx;
970 		info->rates[i].Tries = rates[i].count;
971 
972 		    if (rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) {
973 			info->rates[i].RateFlags |= ATH9K_RATESERIES_RTS_CTS;
974 			info->flags |= ATH9K_TXDESC_RTSENA;
975 		} else if (rates[i].flags & IEEE80211_TX_RC_USE_CTS_PROTECT) {
976 			info->rates[i].RateFlags |= ATH9K_RATESERIES_RTS_CTS;
977 			info->flags |= ATH9K_TXDESC_CTSENA;
978 		}
979 
980 		if (rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
981 			info->rates[i].RateFlags |= ATH9K_RATESERIES_2040;
982 		if (rates[i].flags & IEEE80211_TX_RC_SHORT_GI)
983 			info->rates[i].RateFlags |= ATH9K_RATESERIES_HALFGI;
984 
985 		is_sgi = !!(rates[i].flags & IEEE80211_TX_RC_SHORT_GI);
986 		is_40 = !!(rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH);
987 		is_sp = !!(rates[i].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
988 
989 		if (rates[i].flags & IEEE80211_TX_RC_MCS) {
990 			/* MCS rates */
991 			info->rates[i].Rate = rix | 0x80;
992 			info->rates[i].ChSel = ath_txchainmask_reduction(sc,
993 					ah->txchainmask, info->rates[i].Rate);
994 			info->rates[i].PktDuration = ath_pkt_duration(sc, rix, len,
995 				 is_40, is_sgi, is_sp);
996 			if (rix < 8 && (tx_info->flags & IEEE80211_TX_CTL_STBC))
997 				info->rates[i].RateFlags |= ATH9K_RATESERIES_STBC;
998 			continue;
999 		}
1000 
1001 		/* legacy rates */
1002 		if ((tx_info->band == IEEE80211_BAND_2GHZ) &&
1003 		    !(rate->flags & IEEE80211_RATE_ERP_G))
1004 			phy = WLAN_RC_PHY_CCK;
1005 		else
1006 			phy = WLAN_RC_PHY_OFDM;
1007 
1008 		rate = &sc->sbands[tx_info->band].bitrates[rates[i].idx];
1009 		info->rates[i].Rate = rate->hw_value;
1010 		if (rate->hw_value_short) {
1011 			if (rates[i].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
1012 				info->rates[i].Rate |= rate->hw_value_short;
1013 		} else {
1014 			is_sp = false;
1015 		}
1016 
1017 		if (bf->bf_state.bfs_paprd)
1018 			info->rates[i].ChSel = ah->txchainmask;
1019 		else
1020 			info->rates[i].ChSel = ath_txchainmask_reduction(sc,
1021 					ah->txchainmask, info->rates[i].Rate);
1022 
1023 		info->rates[i].PktDuration = ath9k_hw_computetxtime(sc->sc_ah,
1024 			phy, rate->bitrate * 100, len, rix, is_sp);
1025 	}
1026 
1027 	/* For AR5416 - RTS cannot be followed by a frame larger than 8K */
1028 	if (bf_isaggr(bf) && (len > sc->sc_ah->caps.rts_aggr_limit))
1029 		info->flags &= ~ATH9K_TXDESC_RTSENA;
1030 
1031 	/* ATH9K_TXDESC_RTSENA and ATH9K_TXDESC_CTSENA are mutually exclusive. */
1032 	if (info->flags & ATH9K_TXDESC_RTSENA)
1033 		info->flags &= ~ATH9K_TXDESC_CTSENA;
1034 }
1035 
1036 static enum ath9k_pkt_type get_hw_packet_type(struct sk_buff *skb)
1037 {
1038 	struct ieee80211_hdr *hdr;
1039 	enum ath9k_pkt_type htype;
1040 	__le16 fc;
1041 
1042 	hdr = (struct ieee80211_hdr *)skb->data;
1043 	fc = hdr->frame_control;
1044 
1045 	if (ieee80211_is_beacon(fc))
1046 		htype = ATH9K_PKT_TYPE_BEACON;
1047 	else if (ieee80211_is_probe_resp(fc))
1048 		htype = ATH9K_PKT_TYPE_PROBE_RESP;
1049 	else if (ieee80211_is_atim(fc))
1050 		htype = ATH9K_PKT_TYPE_ATIM;
1051 	else if (ieee80211_is_pspoll(fc))
1052 		htype = ATH9K_PKT_TYPE_PSPOLL;
1053 	else
1054 		htype = ATH9K_PKT_TYPE_NORMAL;
1055 
1056 	return htype;
1057 }
1058 
1059 static void ath_tx_fill_desc(struct ath_softc *sc, struct ath_buf *bf,
1060 			     struct ath_txq *txq, int len)
1061 {
1062 	struct ath_hw *ah = sc->sc_ah;
1063 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(bf->bf_mpdu);
1064 	struct ath_buf *bf_first = bf;
1065 	struct ath_tx_info info;
1066 	bool aggr = !!(bf->bf_state.bf_type & BUF_AGGR);
1067 
1068 	memset(&info, 0, sizeof(info));
1069 	info.is_first = true;
1070 	info.is_last = true;
1071 	info.txpower = MAX_RATE_POWER;
1072 	info.qcu = txq->axq_qnum;
1073 
1074 	info.flags = ATH9K_TXDESC_INTREQ;
1075 	if (tx_info->flags & IEEE80211_TX_CTL_NO_ACK)
1076 		info.flags |= ATH9K_TXDESC_NOACK;
1077 	if (tx_info->flags & IEEE80211_TX_CTL_LDPC)
1078 		info.flags |= ATH9K_TXDESC_LDPC;
1079 
1080 	ath_buf_set_rate(sc, bf, &info, len);
1081 
1082 	if (tx_info->flags & IEEE80211_TX_CTL_CLEAR_PS_FILT)
1083 		info.flags |= ATH9K_TXDESC_CLRDMASK;
1084 
1085 	if (bf->bf_state.bfs_paprd)
1086 		info.flags |= (u32) bf->bf_state.bfs_paprd << ATH9K_TXDESC_PAPRD_S;
1087 
1088 
1089 	while (bf) {
1090 		struct sk_buff *skb = bf->bf_mpdu;
1091 		struct ath_frame_info *fi = get_frame_info(skb);
1092 
1093 		info.type = get_hw_packet_type(skb);
1094 		if (bf->bf_next)
1095 			info.link = bf->bf_next->bf_daddr;
1096 		else
1097 			info.link = 0;
1098 
1099 		info.buf_addr[0] = bf->bf_buf_addr;
1100 		info.buf_len[0] = skb->len;
1101 		info.pkt_len = fi->framelen;
1102 		info.keyix = fi->keyix;
1103 		info.keytype = fi->keytype;
1104 
1105 		if (aggr) {
1106 			if (bf == bf_first)
1107 				info.aggr = AGGR_BUF_FIRST;
1108 			else if (!bf->bf_next)
1109 				info.aggr = AGGR_BUF_LAST;
1110 			else
1111 				info.aggr = AGGR_BUF_MIDDLE;
1112 
1113 			info.ndelim = bf->bf_state.ndelim;
1114 			info.aggr_len = len;
1115 		}
1116 
1117 		ath9k_hw_set_txdesc(ah, bf->bf_desc, &info);
1118 		bf = bf->bf_next;
1119 	}
1120 }
1121 
1122 static void ath_tx_sched_aggr(struct ath_softc *sc, struct ath_txq *txq,
1123 			      struct ath_atx_tid *tid)
1124 {
1125 	struct ath_buf *bf;
1126 	enum ATH_AGGR_STATUS status;
1127 	struct ieee80211_tx_info *tx_info;
1128 	struct list_head bf_q;
1129 	int aggr_len;
1130 
1131 	do {
1132 		if (skb_queue_empty(&tid->buf_q))
1133 			return;
1134 
1135 		INIT_LIST_HEAD(&bf_q);
1136 
1137 		status = ath_tx_form_aggr(sc, txq, tid, &bf_q, &aggr_len);
1138 
1139 		/*
1140 		 * no frames picked up to be aggregated;
1141 		 * block-ack window is not open.
1142 		 */
1143 		if (list_empty(&bf_q))
1144 			break;
1145 
1146 		bf = list_first_entry(&bf_q, struct ath_buf, list);
1147 		bf->bf_lastbf = list_entry(bf_q.prev, struct ath_buf, list);
1148 		tx_info = IEEE80211_SKB_CB(bf->bf_mpdu);
1149 
1150 		if (tid->ac->clear_ps_filter) {
1151 			tid->ac->clear_ps_filter = false;
1152 			tx_info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1153 		} else {
1154 			tx_info->flags &= ~IEEE80211_TX_CTL_CLEAR_PS_FILT;
1155 		}
1156 
1157 		/* if only one frame, send as non-aggregate */
1158 		if (bf == bf->bf_lastbf) {
1159 			aggr_len = get_frame_info(bf->bf_mpdu)->framelen;
1160 			bf->bf_state.bf_type = BUF_AMPDU;
1161 		} else {
1162 			TX_STAT_INC(txq->axq_qnum, a_aggr);
1163 		}
1164 
1165 		ath_tx_fill_desc(sc, bf, txq, aggr_len);
1166 		ath_tx_txqaddbuf(sc, txq, &bf_q, false);
1167 	} while (txq->axq_ampdu_depth < ATH_AGGR_MIN_QDEPTH &&
1168 		 status != ATH_AGGR_BAW_CLOSED);
1169 }
1170 
1171 int ath_tx_aggr_start(struct ath_softc *sc, struct ieee80211_sta *sta,
1172 		      u16 tid, u16 *ssn)
1173 {
1174 	struct ath_atx_tid *txtid;
1175 	struct ath_node *an;
1176 
1177 	an = (struct ath_node *)sta->drv_priv;
1178 	txtid = ATH_AN_2_TID(an, tid);
1179 
1180 	if (txtid->state & (AGGR_CLEANUP | AGGR_ADDBA_COMPLETE))
1181 		return -EAGAIN;
1182 
1183 	txtid->state |= AGGR_ADDBA_PROGRESS;
1184 	txtid->paused = true;
1185 	*ssn = txtid->seq_start = txtid->seq_next;
1186 	txtid->bar_index = -1;
1187 
1188 	memset(txtid->tx_buf, 0, sizeof(txtid->tx_buf));
1189 	txtid->baw_head = txtid->baw_tail = 0;
1190 
1191 	return 0;
1192 }
1193 
1194 void ath_tx_aggr_stop(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid)
1195 {
1196 	struct ath_node *an = (struct ath_node *)sta->drv_priv;
1197 	struct ath_atx_tid *txtid = ATH_AN_2_TID(an, tid);
1198 	struct ath_txq *txq = txtid->ac->txq;
1199 
1200 	if (txtid->state & AGGR_CLEANUP)
1201 		return;
1202 
1203 	if (!(txtid->state & AGGR_ADDBA_COMPLETE)) {
1204 		txtid->state &= ~AGGR_ADDBA_PROGRESS;
1205 		return;
1206 	}
1207 
1208 	ath_txq_lock(sc, txq);
1209 	txtid->paused = true;
1210 
1211 	/*
1212 	 * If frames are still being transmitted for this TID, they will be
1213 	 * cleaned up during tx completion. To prevent race conditions, this
1214 	 * TID can only be reused after all in-progress subframes have been
1215 	 * completed.
1216 	 */
1217 	if (txtid->baw_head != txtid->baw_tail)
1218 		txtid->state |= AGGR_CLEANUP;
1219 	else
1220 		txtid->state &= ~AGGR_ADDBA_COMPLETE;
1221 
1222 	ath_tx_flush_tid(sc, txtid);
1223 	ath_txq_unlock_complete(sc, txq);
1224 }
1225 
1226 void ath_tx_aggr_sleep(struct ieee80211_sta *sta, struct ath_softc *sc,
1227 		       struct ath_node *an)
1228 {
1229 	struct ath_atx_tid *tid;
1230 	struct ath_atx_ac *ac;
1231 	struct ath_txq *txq;
1232 	bool buffered;
1233 	int tidno;
1234 
1235 	for (tidno = 0, tid = &an->tid[tidno];
1236 	     tidno < WME_NUM_TID; tidno++, tid++) {
1237 
1238 		if (!tid->sched)
1239 			continue;
1240 
1241 		ac = tid->ac;
1242 		txq = ac->txq;
1243 
1244 		ath_txq_lock(sc, txq);
1245 
1246 		buffered = !skb_queue_empty(&tid->buf_q);
1247 
1248 		tid->sched = false;
1249 		list_del(&tid->list);
1250 
1251 		if (ac->sched) {
1252 			ac->sched = false;
1253 			list_del(&ac->list);
1254 		}
1255 
1256 		ath_txq_unlock(sc, txq);
1257 
1258 		ieee80211_sta_set_buffered(sta, tidno, buffered);
1259 	}
1260 }
1261 
1262 void ath_tx_aggr_wakeup(struct ath_softc *sc, struct ath_node *an)
1263 {
1264 	struct ath_atx_tid *tid;
1265 	struct ath_atx_ac *ac;
1266 	struct ath_txq *txq;
1267 	int tidno;
1268 
1269 	for (tidno = 0, tid = &an->tid[tidno];
1270 	     tidno < WME_NUM_TID; tidno++, tid++) {
1271 
1272 		ac = tid->ac;
1273 		txq = ac->txq;
1274 
1275 		ath_txq_lock(sc, txq);
1276 		ac->clear_ps_filter = true;
1277 
1278 		if (!skb_queue_empty(&tid->buf_q) && !tid->paused) {
1279 			ath_tx_queue_tid(txq, tid);
1280 			ath_txq_schedule(sc, txq);
1281 		}
1282 
1283 		ath_txq_unlock_complete(sc, txq);
1284 	}
1285 }
1286 
1287 void ath_tx_aggr_resume(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid)
1288 {
1289 	struct ath_atx_tid *txtid;
1290 	struct ath_node *an;
1291 
1292 	an = (struct ath_node *)sta->drv_priv;
1293 
1294 	if (sc->sc_flags & SC_OP_TXAGGR) {
1295 		txtid = ATH_AN_2_TID(an, tid);
1296 		txtid->baw_size =
1297 			IEEE80211_MIN_AMPDU_BUF << sta->ht_cap.ampdu_factor;
1298 		txtid->state |= AGGR_ADDBA_COMPLETE;
1299 		txtid->state &= ~AGGR_ADDBA_PROGRESS;
1300 		ath_tx_resume_tid(sc, txtid);
1301 	}
1302 }
1303 
1304 /********************/
1305 /* Queue Management */
1306 /********************/
1307 
1308 static void ath_txq_drain_pending_buffers(struct ath_softc *sc,
1309 					  struct ath_txq *txq)
1310 {
1311 	struct ath_atx_ac *ac, *ac_tmp;
1312 	struct ath_atx_tid *tid, *tid_tmp;
1313 
1314 	list_for_each_entry_safe(ac, ac_tmp, &txq->axq_acq, list) {
1315 		list_del(&ac->list);
1316 		ac->sched = false;
1317 		list_for_each_entry_safe(tid, tid_tmp, &ac->tid_q, list) {
1318 			list_del(&tid->list);
1319 			tid->sched = false;
1320 			ath_tid_drain(sc, txq, tid);
1321 		}
1322 	}
1323 }
1324 
1325 struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype)
1326 {
1327 	struct ath_hw *ah = sc->sc_ah;
1328 	struct ath9k_tx_queue_info qi;
1329 	static const int subtype_txq_to_hwq[] = {
1330 		[WME_AC_BE] = ATH_TXQ_AC_BE,
1331 		[WME_AC_BK] = ATH_TXQ_AC_BK,
1332 		[WME_AC_VI] = ATH_TXQ_AC_VI,
1333 		[WME_AC_VO] = ATH_TXQ_AC_VO,
1334 	};
1335 	int axq_qnum, i;
1336 
1337 	memset(&qi, 0, sizeof(qi));
1338 	qi.tqi_subtype = subtype_txq_to_hwq[subtype];
1339 	qi.tqi_aifs = ATH9K_TXQ_USEDEFAULT;
1340 	qi.tqi_cwmin = ATH9K_TXQ_USEDEFAULT;
1341 	qi.tqi_cwmax = ATH9K_TXQ_USEDEFAULT;
1342 	qi.tqi_physCompBuf = 0;
1343 
1344 	/*
1345 	 * Enable interrupts only for EOL and DESC conditions.
1346 	 * We mark tx descriptors to receive a DESC interrupt
1347 	 * when a tx queue gets deep; otherwise waiting for the
1348 	 * EOL to reap descriptors.  Note that this is done to
1349 	 * reduce interrupt load and this only defers reaping
1350 	 * descriptors, never transmitting frames.  Aside from
1351 	 * reducing interrupts this also permits more concurrency.
1352 	 * The only potential downside is if the tx queue backs
1353 	 * up in which case the top half of the kernel may backup
1354 	 * due to a lack of tx descriptors.
1355 	 *
1356 	 * The UAPSD queue is an exception, since we take a desc-
1357 	 * based intr on the EOSP frames.
1358 	 */
1359 	if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
1360 		qi.tqi_qflags = TXQ_FLAG_TXOKINT_ENABLE |
1361 				TXQ_FLAG_TXERRINT_ENABLE;
1362 	} else {
1363 		if (qtype == ATH9K_TX_QUEUE_UAPSD)
1364 			qi.tqi_qflags = TXQ_FLAG_TXDESCINT_ENABLE;
1365 		else
1366 			qi.tqi_qflags = TXQ_FLAG_TXEOLINT_ENABLE |
1367 					TXQ_FLAG_TXDESCINT_ENABLE;
1368 	}
1369 	axq_qnum = ath9k_hw_setuptxqueue(ah, qtype, &qi);
1370 	if (axq_qnum == -1) {
1371 		/*
1372 		 * NB: don't print a message, this happens
1373 		 * normally on parts with too few tx queues
1374 		 */
1375 		return NULL;
1376 	}
1377 	if (!ATH_TXQ_SETUP(sc, axq_qnum)) {
1378 		struct ath_txq *txq = &sc->tx.txq[axq_qnum];
1379 
1380 		txq->axq_qnum = axq_qnum;
1381 		txq->mac80211_qnum = -1;
1382 		txq->axq_link = NULL;
1383 		__skb_queue_head_init(&txq->complete_q);
1384 		INIT_LIST_HEAD(&txq->axq_q);
1385 		INIT_LIST_HEAD(&txq->axq_acq);
1386 		spin_lock_init(&txq->axq_lock);
1387 		txq->axq_depth = 0;
1388 		txq->axq_ampdu_depth = 0;
1389 		txq->axq_tx_inprogress = false;
1390 		sc->tx.txqsetup |= 1<<axq_qnum;
1391 
1392 		txq->txq_headidx = txq->txq_tailidx = 0;
1393 		for (i = 0; i < ATH_TXFIFO_DEPTH; i++)
1394 			INIT_LIST_HEAD(&txq->txq_fifo[i]);
1395 	}
1396 	return &sc->tx.txq[axq_qnum];
1397 }
1398 
1399 int ath_txq_update(struct ath_softc *sc, int qnum,
1400 		   struct ath9k_tx_queue_info *qinfo)
1401 {
1402 	struct ath_hw *ah = sc->sc_ah;
1403 	int error = 0;
1404 	struct ath9k_tx_queue_info qi;
1405 
1406 	if (qnum == sc->beacon.beaconq) {
1407 		/*
1408 		 * XXX: for beacon queue, we just save the parameter.
1409 		 * It will be picked up by ath_beaconq_config when
1410 		 * it's necessary.
1411 		 */
1412 		sc->beacon.beacon_qi = *qinfo;
1413 		return 0;
1414 	}
1415 
1416 	BUG_ON(sc->tx.txq[qnum].axq_qnum != qnum);
1417 
1418 	ath9k_hw_get_txq_props(ah, qnum, &qi);
1419 	qi.tqi_aifs = qinfo->tqi_aifs;
1420 	qi.tqi_cwmin = qinfo->tqi_cwmin;
1421 	qi.tqi_cwmax = qinfo->tqi_cwmax;
1422 	qi.tqi_burstTime = qinfo->tqi_burstTime;
1423 	qi.tqi_readyTime = qinfo->tqi_readyTime;
1424 
1425 	if (!ath9k_hw_set_txq_props(ah, qnum, &qi)) {
1426 		ath_err(ath9k_hw_common(sc->sc_ah),
1427 			"Unable to update hardware queue %u!\n", qnum);
1428 		error = -EIO;
1429 	} else {
1430 		ath9k_hw_resettxqueue(ah, qnum);
1431 	}
1432 
1433 	return error;
1434 }
1435 
1436 int ath_cabq_update(struct ath_softc *sc)
1437 {
1438 	struct ath9k_tx_queue_info qi;
1439 	struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
1440 	int qnum = sc->beacon.cabq->axq_qnum;
1441 
1442 	ath9k_hw_get_txq_props(sc->sc_ah, qnum, &qi);
1443 	/*
1444 	 * Ensure the readytime % is within the bounds.
1445 	 */
1446 	if (sc->config.cabqReadytime < ATH9K_READY_TIME_LO_BOUND)
1447 		sc->config.cabqReadytime = ATH9K_READY_TIME_LO_BOUND;
1448 	else if (sc->config.cabqReadytime > ATH9K_READY_TIME_HI_BOUND)
1449 		sc->config.cabqReadytime = ATH9K_READY_TIME_HI_BOUND;
1450 
1451 	qi.tqi_readyTime = (cur_conf->beacon_interval *
1452 			    sc->config.cabqReadytime) / 100;
1453 	ath_txq_update(sc, qnum, &qi);
1454 
1455 	return 0;
1456 }
1457 
1458 static bool bf_is_ampdu_not_probing(struct ath_buf *bf)
1459 {
1460     struct ieee80211_tx_info *info = IEEE80211_SKB_CB(bf->bf_mpdu);
1461     return bf_isampdu(bf) && !(info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE);
1462 }
1463 
1464 static void ath_drain_txq_list(struct ath_softc *sc, struct ath_txq *txq,
1465 			       struct list_head *list, bool retry_tx)
1466 {
1467 	struct ath_buf *bf, *lastbf;
1468 	struct list_head bf_head;
1469 	struct ath_tx_status ts;
1470 
1471 	memset(&ts, 0, sizeof(ts));
1472 	ts.ts_status = ATH9K_TX_FLUSH;
1473 	INIT_LIST_HEAD(&bf_head);
1474 
1475 	while (!list_empty(list)) {
1476 		bf = list_first_entry(list, struct ath_buf, list);
1477 
1478 		if (bf->bf_stale) {
1479 			list_del(&bf->list);
1480 
1481 			ath_tx_return_buffer(sc, bf);
1482 			continue;
1483 		}
1484 
1485 		lastbf = bf->bf_lastbf;
1486 		list_cut_position(&bf_head, list, &lastbf->list);
1487 
1488 		txq->axq_depth--;
1489 		if (bf_is_ampdu_not_probing(bf))
1490 			txq->axq_ampdu_depth--;
1491 
1492 		if (bf_isampdu(bf))
1493 			ath_tx_complete_aggr(sc, txq, bf, &bf_head, &ts, 0,
1494 					     retry_tx);
1495 		else
1496 			ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0);
1497 	}
1498 }
1499 
1500 /*
1501  * Drain a given TX queue (could be Beacon or Data)
1502  *
1503  * This assumes output has been stopped and
1504  * we do not need to block ath_tx_tasklet.
1505  */
1506 void ath_draintxq(struct ath_softc *sc, struct ath_txq *txq, bool retry_tx)
1507 {
1508 	ath_txq_lock(sc, txq);
1509 
1510 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
1511 		int idx = txq->txq_tailidx;
1512 
1513 		while (!list_empty(&txq->txq_fifo[idx])) {
1514 			ath_drain_txq_list(sc, txq, &txq->txq_fifo[idx],
1515 					   retry_tx);
1516 
1517 			INCR(idx, ATH_TXFIFO_DEPTH);
1518 		}
1519 		txq->txq_tailidx = idx;
1520 	}
1521 
1522 	txq->axq_link = NULL;
1523 	txq->axq_tx_inprogress = false;
1524 	ath_drain_txq_list(sc, txq, &txq->axq_q, retry_tx);
1525 
1526 	/* flush any pending frames if aggregation is enabled */
1527 	if ((sc->sc_flags & SC_OP_TXAGGR) && !retry_tx)
1528 		ath_txq_drain_pending_buffers(sc, txq);
1529 
1530 	ath_txq_unlock_complete(sc, txq);
1531 }
1532 
1533 bool ath_drain_all_txq(struct ath_softc *sc, bool retry_tx)
1534 {
1535 	struct ath_hw *ah = sc->sc_ah;
1536 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1537 	struct ath_txq *txq;
1538 	int i;
1539 	u32 npend = 0;
1540 
1541 	if (sc->sc_flags & SC_OP_INVALID)
1542 		return true;
1543 
1544 	ath9k_hw_abort_tx_dma(ah);
1545 
1546 	/* Check if any queue remains active */
1547 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
1548 		if (!ATH_TXQ_SETUP(sc, i))
1549 			continue;
1550 
1551 		if (ath9k_hw_numtxpending(ah, sc->tx.txq[i].axq_qnum))
1552 			npend |= BIT(i);
1553 	}
1554 
1555 	if (npend)
1556 		ath_err(common, "Failed to stop TX DMA, queues=0x%03x!\n", npend);
1557 
1558 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
1559 		if (!ATH_TXQ_SETUP(sc, i))
1560 			continue;
1561 
1562 		/*
1563 		 * The caller will resume queues with ieee80211_wake_queues.
1564 		 * Mark the queue as not stopped to prevent ath_tx_complete
1565 		 * from waking the queue too early.
1566 		 */
1567 		txq = &sc->tx.txq[i];
1568 		txq->stopped = false;
1569 		ath_draintxq(sc, txq, retry_tx);
1570 	}
1571 
1572 	return !npend;
1573 }
1574 
1575 void ath_tx_cleanupq(struct ath_softc *sc, struct ath_txq *txq)
1576 {
1577 	ath9k_hw_releasetxqueue(sc->sc_ah, txq->axq_qnum);
1578 	sc->tx.txqsetup &= ~(1<<txq->axq_qnum);
1579 }
1580 
1581 /* For each axq_acq entry, for each tid, try to schedule packets
1582  * for transmit until ampdu_depth has reached min Q depth.
1583  */
1584 void ath_txq_schedule(struct ath_softc *sc, struct ath_txq *txq)
1585 {
1586 	struct ath_atx_ac *ac, *ac_tmp, *last_ac;
1587 	struct ath_atx_tid *tid, *last_tid;
1588 
1589 	if (work_pending(&sc->hw_reset_work) || list_empty(&txq->axq_acq) ||
1590 	    txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH)
1591 		return;
1592 
1593 	ac = list_first_entry(&txq->axq_acq, struct ath_atx_ac, list);
1594 	last_ac = list_entry(txq->axq_acq.prev, struct ath_atx_ac, list);
1595 
1596 	list_for_each_entry_safe(ac, ac_tmp, &txq->axq_acq, list) {
1597 		last_tid = list_entry(ac->tid_q.prev, struct ath_atx_tid, list);
1598 		list_del(&ac->list);
1599 		ac->sched = false;
1600 
1601 		while (!list_empty(&ac->tid_q)) {
1602 			tid = list_first_entry(&ac->tid_q, struct ath_atx_tid,
1603 					       list);
1604 			list_del(&tid->list);
1605 			tid->sched = false;
1606 
1607 			if (tid->paused)
1608 				continue;
1609 
1610 			ath_tx_sched_aggr(sc, txq, tid);
1611 
1612 			/*
1613 			 * add tid to round-robin queue if more frames
1614 			 * are pending for the tid
1615 			 */
1616 			if (!skb_queue_empty(&tid->buf_q))
1617 				ath_tx_queue_tid(txq, tid);
1618 
1619 			if (tid == last_tid ||
1620 			    txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH)
1621 				break;
1622 		}
1623 
1624 		if (!list_empty(&ac->tid_q) && !ac->sched) {
1625 			ac->sched = true;
1626 			list_add_tail(&ac->list, &txq->axq_acq);
1627 		}
1628 
1629 		if (ac == last_ac ||
1630 		    txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH)
1631 			return;
1632 	}
1633 }
1634 
1635 /***********/
1636 /* TX, DMA */
1637 /***********/
1638 
1639 /*
1640  * Insert a chain of ath_buf (descriptors) on a txq and
1641  * assume the descriptors are already chained together by caller.
1642  */
1643 static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq,
1644 			     struct list_head *head, bool internal)
1645 {
1646 	struct ath_hw *ah = sc->sc_ah;
1647 	struct ath_common *common = ath9k_hw_common(ah);
1648 	struct ath_buf *bf, *bf_last;
1649 	bool puttxbuf = false;
1650 	bool edma;
1651 
1652 	/*
1653 	 * Insert the frame on the outbound list and
1654 	 * pass it on to the hardware.
1655 	 */
1656 
1657 	if (list_empty(head))
1658 		return;
1659 
1660 	edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
1661 	bf = list_first_entry(head, struct ath_buf, list);
1662 	bf_last = list_entry(head->prev, struct ath_buf, list);
1663 
1664 	ath_dbg(common, QUEUE, "qnum: %d, txq depth: %d\n",
1665 		txq->axq_qnum, txq->axq_depth);
1666 
1667 	if (edma && list_empty(&txq->txq_fifo[txq->txq_headidx])) {
1668 		list_splice_tail_init(head, &txq->txq_fifo[txq->txq_headidx]);
1669 		INCR(txq->txq_headidx, ATH_TXFIFO_DEPTH);
1670 		puttxbuf = true;
1671 	} else {
1672 		list_splice_tail_init(head, &txq->axq_q);
1673 
1674 		if (txq->axq_link) {
1675 			ath9k_hw_set_desc_link(ah, txq->axq_link, bf->bf_daddr);
1676 			ath_dbg(common, XMIT, "link[%u] (%p)=%llx (%p)\n",
1677 				txq->axq_qnum, txq->axq_link,
1678 				ito64(bf->bf_daddr), bf->bf_desc);
1679 		} else if (!edma)
1680 			puttxbuf = true;
1681 
1682 		txq->axq_link = bf_last->bf_desc;
1683 	}
1684 
1685 	if (puttxbuf) {
1686 		TX_STAT_INC(txq->axq_qnum, puttxbuf);
1687 		ath9k_hw_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
1688 		ath_dbg(common, XMIT, "TXDP[%u] = %llx (%p)\n",
1689 			txq->axq_qnum, ito64(bf->bf_daddr), bf->bf_desc);
1690 	}
1691 
1692 	if (!edma) {
1693 		TX_STAT_INC(txq->axq_qnum, txstart);
1694 		ath9k_hw_txstart(ah, txq->axq_qnum);
1695 	}
1696 
1697 	if (!internal) {
1698 		txq->axq_depth++;
1699 		if (bf_is_ampdu_not_probing(bf))
1700 			txq->axq_ampdu_depth++;
1701 	}
1702 }
1703 
1704 static void ath_tx_send_ampdu(struct ath_softc *sc, struct ath_atx_tid *tid,
1705 			      struct sk_buff *skb, struct ath_tx_control *txctl)
1706 {
1707 	struct ath_frame_info *fi = get_frame_info(skb);
1708 	struct list_head bf_head;
1709 	struct ath_buf *bf;
1710 
1711 	/*
1712 	 * Do not queue to h/w when any of the following conditions is true:
1713 	 * - there are pending frames in software queue
1714 	 * - the TID is currently paused for ADDBA/BAR request
1715 	 * - seqno is not within block-ack window
1716 	 * - h/w queue depth exceeds low water mark
1717 	 */
1718 	if (!skb_queue_empty(&tid->buf_q) || tid->paused ||
1719 	    !BAW_WITHIN(tid->seq_start, tid->baw_size, tid->seq_next) ||
1720 	    txctl->txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH) {
1721 		/*
1722 		 * Add this frame to software queue for scheduling later
1723 		 * for aggregation.
1724 		 */
1725 		TX_STAT_INC(txctl->txq->axq_qnum, a_queued_sw);
1726 		__skb_queue_tail(&tid->buf_q, skb);
1727 		if (!txctl->an || !txctl->an->sleeping)
1728 			ath_tx_queue_tid(txctl->txq, tid);
1729 		return;
1730 	}
1731 
1732 	bf = ath_tx_setup_buffer(sc, txctl->txq, tid, skb);
1733 	if (!bf)
1734 		return;
1735 
1736 	bf->bf_state.bf_type = BUF_AMPDU;
1737 	INIT_LIST_HEAD(&bf_head);
1738 	list_add(&bf->list, &bf_head);
1739 
1740 	/* Add sub-frame to BAW */
1741 	ath_tx_addto_baw(sc, tid, bf->bf_state.seqno);
1742 
1743 	/* Queue to h/w without aggregation */
1744 	TX_STAT_INC(txctl->txq->axq_qnum, a_queued_hw);
1745 	bf->bf_lastbf = bf;
1746 	ath_tx_fill_desc(sc, bf, txctl->txq, fi->framelen);
1747 	ath_tx_txqaddbuf(sc, txctl->txq, &bf_head, false);
1748 }
1749 
1750 static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
1751 			       struct ath_atx_tid *tid, struct sk_buff *skb)
1752 {
1753 	struct ath_frame_info *fi = get_frame_info(skb);
1754 	struct list_head bf_head;
1755 	struct ath_buf *bf;
1756 
1757 	bf = fi->bf;
1758 	if (!bf)
1759 		bf = ath_tx_setup_buffer(sc, txq, tid, skb);
1760 
1761 	if (!bf)
1762 		return;
1763 
1764 	INIT_LIST_HEAD(&bf_head);
1765 	list_add_tail(&bf->list, &bf_head);
1766 	bf->bf_state.bf_type = 0;
1767 
1768 	bf->bf_lastbf = bf;
1769 	ath_tx_fill_desc(sc, bf, txq, fi->framelen);
1770 	ath_tx_txqaddbuf(sc, txq, &bf_head, false);
1771 	TX_STAT_INC(txq->axq_qnum, queued);
1772 }
1773 
1774 static void setup_frame_info(struct ieee80211_hw *hw, struct sk_buff *skb,
1775 			     int framelen)
1776 {
1777 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1778 	struct ieee80211_sta *sta = tx_info->control.sta;
1779 	struct ieee80211_key_conf *hw_key = tx_info->control.hw_key;
1780 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1781 	struct ath_frame_info *fi = get_frame_info(skb);
1782 	struct ath_node *an = NULL;
1783 	enum ath9k_key_type keytype;
1784 
1785 	keytype = ath9k_cmn_get_hw_crypto_keytype(skb);
1786 
1787 	if (sta)
1788 		an = (struct ath_node *) sta->drv_priv;
1789 
1790 	memset(fi, 0, sizeof(*fi));
1791 	if (hw_key)
1792 		fi->keyix = hw_key->hw_key_idx;
1793 	else if (an && ieee80211_is_data(hdr->frame_control) && an->ps_key > 0)
1794 		fi->keyix = an->ps_key;
1795 	else
1796 		fi->keyix = ATH9K_TXKEYIX_INVALID;
1797 	fi->keytype = keytype;
1798 	fi->framelen = framelen;
1799 }
1800 
1801 u8 ath_txchainmask_reduction(struct ath_softc *sc, u8 chainmask, u32 rate)
1802 {
1803 	struct ath_hw *ah = sc->sc_ah;
1804 	struct ath9k_channel *curchan = ah->curchan;
1805 	if ((ah->caps.hw_caps & ATH9K_HW_CAP_APM) &&
1806 	    (curchan->channelFlags & CHANNEL_5GHZ) &&
1807 	    (chainmask == 0x7) && (rate < 0x90))
1808 		return 0x3;
1809 	else
1810 		return chainmask;
1811 }
1812 
1813 /*
1814  * Assign a descriptor (and sequence number if necessary,
1815  * and map buffer for DMA. Frees skb on error
1816  */
1817 static struct ath_buf *ath_tx_setup_buffer(struct ath_softc *sc,
1818 					   struct ath_txq *txq,
1819 					   struct ath_atx_tid *tid,
1820 					   struct sk_buff *skb)
1821 {
1822 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1823 	struct ath_frame_info *fi = get_frame_info(skb);
1824 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1825 	struct ath_buf *bf;
1826 	u16 seqno;
1827 
1828 	bf = ath_tx_get_buffer(sc);
1829 	if (!bf) {
1830 		ath_dbg(common, XMIT, "TX buffers are full\n");
1831 		goto error;
1832 	}
1833 
1834 	ATH_TXBUF_RESET(bf);
1835 
1836 	if (tid) {
1837 		seqno = tid->seq_next;
1838 		hdr->seq_ctrl = cpu_to_le16(tid->seq_next << IEEE80211_SEQ_SEQ_SHIFT);
1839 		INCR(tid->seq_next, IEEE80211_SEQ_MAX);
1840 		bf->bf_state.seqno = seqno;
1841 	}
1842 
1843 	bf->bf_mpdu = skb;
1844 
1845 	bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
1846 					 skb->len, DMA_TO_DEVICE);
1847 	if (unlikely(dma_mapping_error(sc->dev, bf->bf_buf_addr))) {
1848 		bf->bf_mpdu = NULL;
1849 		bf->bf_buf_addr = 0;
1850 		ath_err(ath9k_hw_common(sc->sc_ah),
1851 			"dma_mapping_error() on TX\n");
1852 		ath_tx_return_buffer(sc, bf);
1853 		goto error;
1854 	}
1855 
1856 	fi->bf = bf;
1857 
1858 	return bf;
1859 
1860 error:
1861 	dev_kfree_skb_any(skb);
1862 	return NULL;
1863 }
1864 
1865 /* FIXME: tx power */
1866 static void ath_tx_start_dma(struct ath_softc *sc, struct sk_buff *skb,
1867 			     struct ath_tx_control *txctl)
1868 {
1869 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1870 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1871 	struct ath_atx_tid *tid = NULL;
1872 	struct ath_buf *bf;
1873 	u8 tidno;
1874 
1875 	if ((sc->sc_flags & SC_OP_TXAGGR) && txctl->an &&
1876 		ieee80211_is_data_qos(hdr->frame_control)) {
1877 		tidno = ieee80211_get_qos_ctl(hdr)[0] &
1878 			IEEE80211_QOS_CTL_TID_MASK;
1879 		tid = ATH_AN_2_TID(txctl->an, tidno);
1880 
1881 		WARN_ON(tid->ac->txq != txctl->txq);
1882 	}
1883 
1884 	if ((tx_info->flags & IEEE80211_TX_CTL_AMPDU) && tid) {
1885 		/*
1886 		 * Try aggregation if it's a unicast data frame
1887 		 * and the destination is HT capable.
1888 		 */
1889 		ath_tx_send_ampdu(sc, tid, skb, txctl);
1890 	} else {
1891 		bf = ath_tx_setup_buffer(sc, txctl->txq, tid, skb);
1892 		if (!bf)
1893 			return;
1894 
1895 		bf->bf_state.bfs_paprd = txctl->paprd;
1896 
1897 		if (txctl->paprd)
1898 			bf->bf_state.bfs_paprd_timestamp = jiffies;
1899 
1900 		ath_tx_send_normal(sc, txctl->txq, tid, skb);
1901 	}
1902 }
1903 
1904 /* Upon failure caller should free skb */
1905 int ath_tx_start(struct ieee80211_hw *hw, struct sk_buff *skb,
1906 		 struct ath_tx_control *txctl)
1907 {
1908 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1909 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1910 	struct ieee80211_sta *sta = info->control.sta;
1911 	struct ieee80211_vif *vif = info->control.vif;
1912 	struct ath_softc *sc = hw->priv;
1913 	struct ath_txq *txq = txctl->txq;
1914 	int padpos, padsize;
1915 	int frmlen = skb->len + FCS_LEN;
1916 	int q;
1917 
1918 	/* NOTE:  sta can be NULL according to net/mac80211.h */
1919 	if (sta)
1920 		txctl->an = (struct ath_node *)sta->drv_priv;
1921 
1922 	if (info->control.hw_key)
1923 		frmlen += info->control.hw_key->icv_len;
1924 
1925 	/*
1926 	 * As a temporary workaround, assign seq# here; this will likely need
1927 	 * to be cleaned up to work better with Beacon transmission and virtual
1928 	 * BSSes.
1929 	 */
1930 	if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
1931 		if (info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)
1932 			sc->tx.seq_no += 0x10;
1933 		hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
1934 		hdr->seq_ctrl |= cpu_to_le16(sc->tx.seq_no);
1935 	}
1936 
1937 	/* Add the padding after the header if this is not already done */
1938 	padpos = ath9k_cmn_padpos(hdr->frame_control);
1939 	padsize = padpos & 3;
1940 	if (padsize && skb->len > padpos) {
1941 		if (skb_headroom(skb) < padsize)
1942 			return -ENOMEM;
1943 
1944 		skb_push(skb, padsize);
1945 		memmove(skb->data, skb->data + padsize, padpos);
1946 		hdr = (struct ieee80211_hdr *) skb->data;
1947 	}
1948 
1949 	if ((vif && vif->type != NL80211_IFTYPE_AP &&
1950 	            vif->type != NL80211_IFTYPE_AP_VLAN) ||
1951 	    !ieee80211_is_data(hdr->frame_control))
1952 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1953 
1954 	setup_frame_info(hw, skb, frmlen);
1955 
1956 	/*
1957 	 * At this point, the vif, hw_key and sta pointers in the tx control
1958 	 * info are no longer valid (overwritten by the ath_frame_info data.
1959 	 */
1960 
1961 	q = skb_get_queue_mapping(skb);
1962 
1963 	ath_txq_lock(sc, txq);
1964 	if (txq == sc->tx.txq_map[q] &&
1965 	    ++txq->pending_frames > ATH_MAX_QDEPTH && !txq->stopped) {
1966 		ieee80211_stop_queue(sc->hw, q);
1967 		txq->stopped = true;
1968 	}
1969 
1970 	ath_tx_start_dma(sc, skb, txctl);
1971 
1972 	ath_txq_unlock(sc, txq);
1973 
1974 	return 0;
1975 }
1976 
1977 /*****************/
1978 /* TX Completion */
1979 /*****************/
1980 
1981 static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
1982 			    int tx_flags, struct ath_txq *txq)
1983 {
1984 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1985 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1986 	struct ieee80211_hdr * hdr = (struct ieee80211_hdr *)skb->data;
1987 	int q, padpos, padsize;
1988 
1989 	ath_dbg(common, XMIT, "TX complete: skb: %p\n", skb);
1990 
1991 	if (!(tx_flags & ATH_TX_ERROR))
1992 		/* Frame was ACKed */
1993 		tx_info->flags |= IEEE80211_TX_STAT_ACK;
1994 
1995 	padpos = ath9k_cmn_padpos(hdr->frame_control);
1996 	padsize = padpos & 3;
1997 	if (padsize && skb->len>padpos+padsize) {
1998 		/*
1999 		 * Remove MAC header padding before giving the frame back to
2000 		 * mac80211.
2001 		 */
2002 		memmove(skb->data + padsize, skb->data, padpos);
2003 		skb_pull(skb, padsize);
2004 	}
2005 
2006 	if ((sc->ps_flags & PS_WAIT_FOR_TX_ACK) && !txq->axq_depth) {
2007 		sc->ps_flags &= ~PS_WAIT_FOR_TX_ACK;
2008 		ath_dbg(common, PS,
2009 			"Going back to sleep after having received TX status (0x%lx)\n",
2010 			sc->ps_flags & (PS_WAIT_FOR_BEACON |
2011 					PS_WAIT_FOR_CAB |
2012 					PS_WAIT_FOR_PSPOLL_DATA |
2013 					PS_WAIT_FOR_TX_ACK));
2014 	}
2015 
2016 	q = skb_get_queue_mapping(skb);
2017 	if (txq == sc->tx.txq_map[q]) {
2018 		if (WARN_ON(--txq->pending_frames < 0))
2019 			txq->pending_frames = 0;
2020 
2021 		if (txq->stopped && txq->pending_frames < ATH_MAX_QDEPTH) {
2022 			ieee80211_wake_queue(sc->hw, q);
2023 			txq->stopped = false;
2024 		}
2025 	}
2026 
2027 	__skb_queue_tail(&txq->complete_q, skb);
2028 }
2029 
2030 static void ath_tx_complete_buf(struct ath_softc *sc, struct ath_buf *bf,
2031 				struct ath_txq *txq, struct list_head *bf_q,
2032 				struct ath_tx_status *ts, int txok)
2033 {
2034 	struct sk_buff *skb = bf->bf_mpdu;
2035 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
2036 	unsigned long flags;
2037 	int tx_flags = 0;
2038 
2039 	if (!txok)
2040 		tx_flags |= ATH_TX_ERROR;
2041 
2042 	if (ts->ts_status & ATH9K_TXERR_FILT)
2043 		tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
2044 
2045 	dma_unmap_single(sc->dev, bf->bf_buf_addr, skb->len, DMA_TO_DEVICE);
2046 	bf->bf_buf_addr = 0;
2047 
2048 	if (bf->bf_state.bfs_paprd) {
2049 		if (time_after(jiffies,
2050 				bf->bf_state.bfs_paprd_timestamp +
2051 				msecs_to_jiffies(ATH_PAPRD_TIMEOUT)))
2052 			dev_kfree_skb_any(skb);
2053 		else
2054 			complete(&sc->paprd_complete);
2055 	} else {
2056 		ath_debug_stat_tx(sc, bf, ts, txq, tx_flags);
2057 		ath_tx_complete(sc, skb, tx_flags, txq);
2058 	}
2059 	/* At this point, skb (bf->bf_mpdu) is consumed...make sure we don't
2060 	 * accidentally reference it later.
2061 	 */
2062 	bf->bf_mpdu = NULL;
2063 
2064 	/*
2065 	 * Return the list of ath_buf of this mpdu to free queue
2066 	 */
2067 	spin_lock_irqsave(&sc->tx.txbuflock, flags);
2068 	list_splice_tail_init(bf_q, &sc->tx.txbuf);
2069 	spin_unlock_irqrestore(&sc->tx.txbuflock, flags);
2070 }
2071 
2072 static void ath_tx_rc_status(struct ath_softc *sc, struct ath_buf *bf,
2073 			     struct ath_tx_status *ts, int nframes, int nbad,
2074 			     int txok)
2075 {
2076 	struct sk_buff *skb = bf->bf_mpdu;
2077 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2078 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
2079 	struct ieee80211_hw *hw = sc->hw;
2080 	struct ath_hw *ah = sc->sc_ah;
2081 	u8 i, tx_rateindex;
2082 
2083 	if (txok)
2084 		tx_info->status.ack_signal = ts->ts_rssi;
2085 
2086 	tx_rateindex = ts->ts_rateindex;
2087 	WARN_ON(tx_rateindex >= hw->max_rates);
2088 
2089 	if (tx_info->flags & IEEE80211_TX_CTL_AMPDU) {
2090 		tx_info->flags |= IEEE80211_TX_STAT_AMPDU;
2091 
2092 		BUG_ON(nbad > nframes);
2093 	}
2094 	tx_info->status.ampdu_len = nframes;
2095 	tx_info->status.ampdu_ack_len = nframes - nbad;
2096 
2097 	if ((ts->ts_status & ATH9K_TXERR_FILT) == 0 &&
2098 	    (tx_info->flags & IEEE80211_TX_CTL_NO_ACK) == 0) {
2099 		/*
2100 		 * If an underrun error is seen assume it as an excessive
2101 		 * retry only if max frame trigger level has been reached
2102 		 * (2 KB for single stream, and 4 KB for dual stream).
2103 		 * Adjust the long retry as if the frame was tried
2104 		 * hw->max_rate_tries times to affect how rate control updates
2105 		 * PER for the failed rate.
2106 		 * In case of congestion on the bus penalizing this type of
2107 		 * underruns should help hardware actually transmit new frames
2108 		 * successfully by eventually preferring slower rates.
2109 		 * This itself should also alleviate congestion on the bus.
2110 		 */
2111 		if (unlikely(ts->ts_flags & (ATH9K_TX_DATA_UNDERRUN |
2112 		                             ATH9K_TX_DELIM_UNDERRUN)) &&
2113 		    ieee80211_is_data(hdr->frame_control) &&
2114 		    ah->tx_trig_level >= sc->sc_ah->config.max_txtrig_level)
2115 			tx_info->status.rates[tx_rateindex].count =
2116 				hw->max_rate_tries;
2117 	}
2118 
2119 	for (i = tx_rateindex + 1; i < hw->max_rates; i++) {
2120 		tx_info->status.rates[i].count = 0;
2121 		tx_info->status.rates[i].idx = -1;
2122 	}
2123 
2124 	tx_info->status.rates[tx_rateindex].count = ts->ts_longretry + 1;
2125 }
2126 
2127 static void ath_tx_process_buffer(struct ath_softc *sc, struct ath_txq *txq,
2128 				  struct ath_tx_status *ts, struct ath_buf *bf,
2129 				  struct list_head *bf_head)
2130 {
2131 	int txok;
2132 
2133 	txq->axq_depth--;
2134 	txok = !(ts->ts_status & ATH9K_TXERR_MASK);
2135 	txq->axq_tx_inprogress = false;
2136 	if (bf_is_ampdu_not_probing(bf))
2137 		txq->axq_ampdu_depth--;
2138 
2139 	if (!bf_isampdu(bf)) {
2140 		ath_tx_rc_status(sc, bf, ts, 1, txok ? 0 : 1, txok);
2141 		ath_tx_complete_buf(sc, bf, txq, bf_head, ts, txok);
2142 	} else
2143 		ath_tx_complete_aggr(sc, txq, bf, bf_head, ts, txok, true);
2144 
2145 	if (sc->sc_flags & SC_OP_TXAGGR)
2146 		ath_txq_schedule(sc, txq);
2147 }
2148 
2149 static void ath_tx_processq(struct ath_softc *sc, struct ath_txq *txq)
2150 {
2151 	struct ath_hw *ah = sc->sc_ah;
2152 	struct ath_common *common = ath9k_hw_common(ah);
2153 	struct ath_buf *bf, *lastbf, *bf_held = NULL;
2154 	struct list_head bf_head;
2155 	struct ath_desc *ds;
2156 	struct ath_tx_status ts;
2157 	int status;
2158 
2159 	ath_dbg(common, QUEUE, "tx queue %d (%x), link %p\n",
2160 		txq->axq_qnum, ath9k_hw_gettxbuf(sc->sc_ah, txq->axq_qnum),
2161 		txq->axq_link);
2162 
2163 	ath_txq_lock(sc, txq);
2164 	for (;;) {
2165 		if (work_pending(&sc->hw_reset_work))
2166 			break;
2167 
2168 		if (list_empty(&txq->axq_q)) {
2169 			txq->axq_link = NULL;
2170 			if (sc->sc_flags & SC_OP_TXAGGR)
2171 				ath_txq_schedule(sc, txq);
2172 			break;
2173 		}
2174 		bf = list_first_entry(&txq->axq_q, struct ath_buf, list);
2175 
2176 		/*
2177 		 * There is a race condition that a BH gets scheduled
2178 		 * after sw writes TxE and before hw re-load the last
2179 		 * descriptor to get the newly chained one.
2180 		 * Software must keep the last DONE descriptor as a
2181 		 * holding descriptor - software does so by marking
2182 		 * it with the STALE flag.
2183 		 */
2184 		bf_held = NULL;
2185 		if (bf->bf_stale) {
2186 			bf_held = bf;
2187 			if (list_is_last(&bf_held->list, &txq->axq_q))
2188 				break;
2189 
2190 			bf = list_entry(bf_held->list.next, struct ath_buf,
2191 					list);
2192 		}
2193 
2194 		lastbf = bf->bf_lastbf;
2195 		ds = lastbf->bf_desc;
2196 
2197 		memset(&ts, 0, sizeof(ts));
2198 		status = ath9k_hw_txprocdesc(ah, ds, &ts);
2199 		if (status == -EINPROGRESS)
2200 			break;
2201 
2202 		TX_STAT_INC(txq->axq_qnum, txprocdesc);
2203 
2204 		/*
2205 		 * Remove ath_buf's of the same transmit unit from txq,
2206 		 * however leave the last descriptor back as the holding
2207 		 * descriptor for hw.
2208 		 */
2209 		lastbf->bf_stale = true;
2210 		INIT_LIST_HEAD(&bf_head);
2211 		if (!list_is_singular(&lastbf->list))
2212 			list_cut_position(&bf_head,
2213 				&txq->axq_q, lastbf->list.prev);
2214 
2215 		if (bf_held) {
2216 			list_del(&bf_held->list);
2217 			ath_tx_return_buffer(sc, bf_held);
2218 		}
2219 
2220 		ath_tx_process_buffer(sc, txq, &ts, bf, &bf_head);
2221 	}
2222 	ath_txq_unlock_complete(sc, txq);
2223 }
2224 
2225 static void ath_tx_complete_poll_work(struct work_struct *work)
2226 {
2227 	struct ath_softc *sc = container_of(work, struct ath_softc,
2228 			tx_complete_work.work);
2229 	struct ath_txq *txq;
2230 	int i;
2231 	bool needreset = false;
2232 #ifdef CONFIG_ATH9K_DEBUGFS
2233 	sc->tx_complete_poll_work_seen++;
2234 #endif
2235 
2236 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++)
2237 		if (ATH_TXQ_SETUP(sc, i)) {
2238 			txq = &sc->tx.txq[i];
2239 			ath_txq_lock(sc, txq);
2240 			if (txq->axq_depth) {
2241 				if (txq->axq_tx_inprogress) {
2242 					needreset = true;
2243 					ath_txq_unlock(sc, txq);
2244 					break;
2245 				} else {
2246 					txq->axq_tx_inprogress = true;
2247 				}
2248 			}
2249 			ath_txq_unlock_complete(sc, txq);
2250 		}
2251 
2252 	if (needreset) {
2253 		ath_dbg(ath9k_hw_common(sc->sc_ah), RESET,
2254 			"tx hung, resetting the chip\n");
2255 		RESET_STAT_INC(sc, RESET_TYPE_TX_HANG);
2256 		ieee80211_queue_work(sc->hw, &sc->hw_reset_work);
2257 	}
2258 
2259 	ieee80211_queue_delayed_work(sc->hw, &sc->tx_complete_work,
2260 			msecs_to_jiffies(ATH_TX_COMPLETE_POLL_INT));
2261 }
2262 
2263 
2264 
2265 void ath_tx_tasklet(struct ath_softc *sc)
2266 {
2267 	int i;
2268 	u32 qcumask = ((1 << ATH9K_NUM_TX_QUEUES) - 1);
2269 
2270 	ath9k_hw_gettxintrtxqs(sc->sc_ah, &qcumask);
2271 
2272 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
2273 		if (ATH_TXQ_SETUP(sc, i) && (qcumask & (1 << i)))
2274 			ath_tx_processq(sc, &sc->tx.txq[i]);
2275 	}
2276 }
2277 
2278 void ath_tx_edma_tasklet(struct ath_softc *sc)
2279 {
2280 	struct ath_tx_status ts;
2281 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2282 	struct ath_hw *ah = sc->sc_ah;
2283 	struct ath_txq *txq;
2284 	struct ath_buf *bf, *lastbf;
2285 	struct list_head bf_head;
2286 	int status;
2287 
2288 	for (;;) {
2289 		if (work_pending(&sc->hw_reset_work))
2290 			break;
2291 
2292 		status = ath9k_hw_txprocdesc(ah, NULL, (void *)&ts);
2293 		if (status == -EINPROGRESS)
2294 			break;
2295 		if (status == -EIO) {
2296 			ath_dbg(common, XMIT, "Error processing tx status\n");
2297 			break;
2298 		}
2299 
2300 		/* Skip beacon completions */
2301 		if (ts.qid == sc->beacon.beaconq)
2302 			continue;
2303 
2304 		txq = &sc->tx.txq[ts.qid];
2305 
2306 		ath_txq_lock(sc, txq);
2307 
2308 		if (list_empty(&txq->txq_fifo[txq->txq_tailidx])) {
2309 			ath_txq_unlock(sc, txq);
2310 			return;
2311 		}
2312 
2313 		bf = list_first_entry(&txq->txq_fifo[txq->txq_tailidx],
2314 				      struct ath_buf, list);
2315 		lastbf = bf->bf_lastbf;
2316 
2317 		INIT_LIST_HEAD(&bf_head);
2318 		list_cut_position(&bf_head, &txq->txq_fifo[txq->txq_tailidx],
2319 				  &lastbf->list);
2320 
2321 		if (list_empty(&txq->txq_fifo[txq->txq_tailidx])) {
2322 			INCR(txq->txq_tailidx, ATH_TXFIFO_DEPTH);
2323 
2324 			if (!list_empty(&txq->axq_q)) {
2325 				struct list_head bf_q;
2326 
2327 				INIT_LIST_HEAD(&bf_q);
2328 				txq->axq_link = NULL;
2329 				list_splice_tail_init(&txq->axq_q, &bf_q);
2330 				ath_tx_txqaddbuf(sc, txq, &bf_q, true);
2331 			}
2332 		}
2333 
2334 		ath_tx_process_buffer(sc, txq, &ts, bf, &bf_head);
2335 		ath_txq_unlock_complete(sc, txq);
2336 	}
2337 }
2338 
2339 /*****************/
2340 /* Init, Cleanup */
2341 /*****************/
2342 
2343 static int ath_txstatus_setup(struct ath_softc *sc, int size)
2344 {
2345 	struct ath_descdma *dd = &sc->txsdma;
2346 	u8 txs_len = sc->sc_ah->caps.txs_len;
2347 
2348 	dd->dd_desc_len = size * txs_len;
2349 	dd->dd_desc = dma_alloc_coherent(sc->dev, dd->dd_desc_len,
2350 					 &dd->dd_desc_paddr, GFP_KERNEL);
2351 	if (!dd->dd_desc)
2352 		return -ENOMEM;
2353 
2354 	return 0;
2355 }
2356 
2357 static int ath_tx_edma_init(struct ath_softc *sc)
2358 {
2359 	int err;
2360 
2361 	err = ath_txstatus_setup(sc, ATH_TXSTATUS_RING_SIZE);
2362 	if (!err)
2363 		ath9k_hw_setup_statusring(sc->sc_ah, sc->txsdma.dd_desc,
2364 					  sc->txsdma.dd_desc_paddr,
2365 					  ATH_TXSTATUS_RING_SIZE);
2366 
2367 	return err;
2368 }
2369 
2370 static void ath_tx_edma_cleanup(struct ath_softc *sc)
2371 {
2372 	struct ath_descdma *dd = &sc->txsdma;
2373 
2374 	dma_free_coherent(sc->dev, dd->dd_desc_len, dd->dd_desc,
2375 			  dd->dd_desc_paddr);
2376 }
2377 
2378 int ath_tx_init(struct ath_softc *sc, int nbufs)
2379 {
2380 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2381 	int error = 0;
2382 
2383 	spin_lock_init(&sc->tx.txbuflock);
2384 
2385 	error = ath_descdma_setup(sc, &sc->tx.txdma, &sc->tx.txbuf,
2386 				  "tx", nbufs, 1, 1);
2387 	if (error != 0) {
2388 		ath_err(common,
2389 			"Failed to allocate tx descriptors: %d\n", error);
2390 		goto err;
2391 	}
2392 
2393 	error = ath_descdma_setup(sc, &sc->beacon.bdma, &sc->beacon.bbuf,
2394 				  "beacon", ATH_BCBUF, 1, 1);
2395 	if (error != 0) {
2396 		ath_err(common,
2397 			"Failed to allocate beacon descriptors: %d\n", error);
2398 		goto err;
2399 	}
2400 
2401 	INIT_DELAYED_WORK(&sc->tx_complete_work, ath_tx_complete_poll_work);
2402 
2403 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
2404 		error = ath_tx_edma_init(sc);
2405 		if (error)
2406 			goto err;
2407 	}
2408 
2409 err:
2410 	if (error != 0)
2411 		ath_tx_cleanup(sc);
2412 
2413 	return error;
2414 }
2415 
2416 void ath_tx_cleanup(struct ath_softc *sc)
2417 {
2418 	if (sc->beacon.bdma.dd_desc_len != 0)
2419 		ath_descdma_cleanup(sc, &sc->beacon.bdma, &sc->beacon.bbuf);
2420 
2421 	if (sc->tx.txdma.dd_desc_len != 0)
2422 		ath_descdma_cleanup(sc, &sc->tx.txdma, &sc->tx.txbuf);
2423 
2424 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
2425 		ath_tx_edma_cleanup(sc);
2426 }
2427 
2428 void ath_tx_node_init(struct ath_softc *sc, struct ath_node *an)
2429 {
2430 	struct ath_atx_tid *tid;
2431 	struct ath_atx_ac *ac;
2432 	int tidno, acno;
2433 
2434 	for (tidno = 0, tid = &an->tid[tidno];
2435 	     tidno < WME_NUM_TID;
2436 	     tidno++, tid++) {
2437 		tid->an        = an;
2438 		tid->tidno     = tidno;
2439 		tid->seq_start = tid->seq_next = 0;
2440 		tid->baw_size  = WME_MAX_BA;
2441 		tid->baw_head  = tid->baw_tail = 0;
2442 		tid->sched     = false;
2443 		tid->paused    = false;
2444 		tid->state &= ~AGGR_CLEANUP;
2445 		__skb_queue_head_init(&tid->buf_q);
2446 		acno = TID_TO_WME_AC(tidno);
2447 		tid->ac = &an->ac[acno];
2448 		tid->state &= ~AGGR_ADDBA_COMPLETE;
2449 		tid->state &= ~AGGR_ADDBA_PROGRESS;
2450 	}
2451 
2452 	for (acno = 0, ac = &an->ac[acno];
2453 	     acno < WME_NUM_AC; acno++, ac++) {
2454 		ac->sched    = false;
2455 		ac->txq = sc->tx.txq_map[acno];
2456 		INIT_LIST_HEAD(&ac->tid_q);
2457 	}
2458 }
2459 
2460 void ath_tx_node_cleanup(struct ath_softc *sc, struct ath_node *an)
2461 {
2462 	struct ath_atx_ac *ac;
2463 	struct ath_atx_tid *tid;
2464 	struct ath_txq *txq;
2465 	int tidno;
2466 
2467 	for (tidno = 0, tid = &an->tid[tidno];
2468 	     tidno < WME_NUM_TID; tidno++, tid++) {
2469 
2470 		ac = tid->ac;
2471 		txq = ac->txq;
2472 
2473 		ath_txq_lock(sc, txq);
2474 
2475 		if (tid->sched) {
2476 			list_del(&tid->list);
2477 			tid->sched = false;
2478 		}
2479 
2480 		if (ac->sched) {
2481 			list_del(&ac->list);
2482 			tid->ac->sched = false;
2483 		}
2484 
2485 		ath_tid_drain(sc, txq, tid);
2486 		tid->state &= ~AGGR_ADDBA_COMPLETE;
2487 		tid->state &= ~AGGR_CLEANUP;
2488 
2489 		ath_txq_unlock(sc, txq);
2490 	}
2491 }
2492