xref: /linux/drivers/net/wireless/ath/ath9k/xmit.c (revision e0bf6c5ca2d3281f231c5f0c9bf145e9513644de)
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 TIME_SYMBOLS(t)         ((t) >> 2)
33 #define TIME_SYMBOLS_HALFGI(t)  (((t) * 5 - 4) / 18)
34 #define NUM_SYMBOLS_PER_USEC(_usec) (_usec >> 2)
35 #define NUM_SYMBOLS_PER_USEC_HALFGI(_usec) (((_usec*5)-4)/18)
36 
37 
38 static u16 bits_per_symbol[][2] = {
39 	/* 20MHz 40MHz */
40 	{    26,   54 },     /*  0: BPSK */
41 	{    52,  108 },     /*  1: QPSK 1/2 */
42 	{    78,  162 },     /*  2: QPSK 3/4 */
43 	{   104,  216 },     /*  3: 16-QAM 1/2 */
44 	{   156,  324 },     /*  4: 16-QAM 3/4 */
45 	{   208,  432 },     /*  5: 64-QAM 2/3 */
46 	{   234,  486 },     /*  6: 64-QAM 3/4 */
47 	{   260,  540 },     /*  7: 64-QAM 5/6 */
48 };
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 /*********************/
77 /* Aggregation logic */
78 /*********************/
79 
80 void ath_txq_lock(struct ath_softc *sc, struct ath_txq *txq)
81 	__acquires(&txq->axq_lock)
82 {
83 	spin_lock_bh(&txq->axq_lock);
84 }
85 
86 void ath_txq_unlock(struct ath_softc *sc, struct ath_txq *txq)
87 	__releases(&txq->axq_lock)
88 {
89 	spin_unlock_bh(&txq->axq_lock);
90 }
91 
92 void ath_txq_unlock_complete(struct ath_softc *sc, struct ath_txq *txq)
93 	__releases(&txq->axq_lock)
94 {
95 	struct sk_buff_head q;
96 	struct sk_buff *skb;
97 
98 	__skb_queue_head_init(&q);
99 	skb_queue_splice_init(&txq->complete_q, &q);
100 	spin_unlock_bh(&txq->axq_lock);
101 
102 	while ((skb = __skb_dequeue(&q)))
103 		ieee80211_tx_status(sc->hw, skb);
104 }
105 
106 static void ath_tx_queue_tid(struct ath_softc *sc, struct ath_txq *txq,
107 			     struct ath_atx_tid *tid)
108 {
109 	struct ath_atx_ac *ac = tid->ac;
110 	struct list_head *list;
111 	struct ath_vif *avp = (struct ath_vif *) tid->an->vif->drv_priv;
112 	struct ath_chanctx *ctx = avp->chanctx;
113 
114 	if (!ctx)
115 		return;
116 
117 	if (tid->sched)
118 		return;
119 
120 	tid->sched = true;
121 	list_add_tail(&tid->list, &ac->tid_q);
122 
123 	if (ac->sched)
124 		return;
125 
126 	ac->sched = true;
127 
128 	list = &ctx->acq[TID_TO_WME_AC(tid->tidno)];
129 	list_add_tail(&ac->list, list);
130 }
131 
132 static struct ath_frame_info *get_frame_info(struct sk_buff *skb)
133 {
134 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
135 	BUILD_BUG_ON(sizeof(struct ath_frame_info) >
136 		     sizeof(tx_info->rate_driver_data));
137 	return (struct ath_frame_info *) &tx_info->rate_driver_data[0];
138 }
139 
140 static void ath_send_bar(struct ath_atx_tid *tid, u16 seqno)
141 {
142 	if (!tid->an->sta)
143 		return;
144 
145 	ieee80211_send_bar(tid->an->vif, tid->an->sta->addr, tid->tidno,
146 			   seqno << IEEE80211_SEQ_SEQ_SHIFT);
147 }
148 
149 static void ath_set_rates(struct ieee80211_vif *vif, struct ieee80211_sta *sta,
150 			  struct ath_buf *bf)
151 {
152 	ieee80211_get_tx_rates(vif, sta, bf->bf_mpdu, bf->rates,
153 			       ARRAY_SIZE(bf->rates));
154 }
155 
156 static void ath_txq_skb_done(struct ath_softc *sc, struct ath_txq *txq,
157 			     struct sk_buff *skb)
158 {
159 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
160 	struct ath_frame_info *fi = get_frame_info(skb);
161 	int q = fi->txq;
162 
163 	if (q < 0)
164 		return;
165 
166 	txq = sc->tx.txq_map[q];
167 	if (WARN_ON(--txq->pending_frames < 0))
168 		txq->pending_frames = 0;
169 
170 	if (txq->stopped &&
171 	    txq->pending_frames < sc->tx.txq_max_pending[q]) {
172 		if (ath9k_is_chanctx_enabled())
173 			ieee80211_wake_queue(sc->hw, info->hw_queue);
174 		else
175 			ieee80211_wake_queue(sc->hw, q);
176 		txq->stopped = false;
177 	}
178 }
179 
180 static struct ath_atx_tid *
181 ath_get_skb_tid(struct ath_softc *sc, struct ath_node *an, struct sk_buff *skb)
182 {
183 	u8 tidno = skb->priority & IEEE80211_QOS_CTL_TID_MASK;
184 	return ATH_AN_2_TID(an, tidno);
185 }
186 
187 static bool ath_tid_has_buffered(struct ath_atx_tid *tid)
188 {
189 	return !skb_queue_empty(&tid->buf_q) || !skb_queue_empty(&tid->retry_q);
190 }
191 
192 static struct sk_buff *ath_tid_dequeue(struct ath_atx_tid *tid)
193 {
194 	struct sk_buff *skb;
195 
196 	skb = __skb_dequeue(&tid->retry_q);
197 	if (!skb)
198 		skb = __skb_dequeue(&tid->buf_q);
199 
200 	return skb;
201 }
202 
203 /*
204  * ath_tx_tid_change_state:
205  * - clears a-mpdu flag of previous session
206  * - force sequence number allocation to fix next BlockAck Window
207  */
208 static void
209 ath_tx_tid_change_state(struct ath_softc *sc, struct ath_atx_tid *tid)
210 {
211 	struct ath_txq *txq = tid->ac->txq;
212 	struct ieee80211_tx_info *tx_info;
213 	struct sk_buff *skb, *tskb;
214 	struct ath_buf *bf;
215 	struct ath_frame_info *fi;
216 
217 	skb_queue_walk_safe(&tid->buf_q, skb, tskb) {
218 		fi = get_frame_info(skb);
219 		bf = fi->bf;
220 
221 		tx_info = IEEE80211_SKB_CB(skb);
222 		tx_info->flags &= ~IEEE80211_TX_CTL_AMPDU;
223 
224 		if (bf)
225 			continue;
226 
227 		bf = ath_tx_setup_buffer(sc, txq, tid, skb);
228 		if (!bf) {
229 			__skb_unlink(skb, &tid->buf_q);
230 			ath_txq_skb_done(sc, txq, skb);
231 			ieee80211_free_txskb(sc->hw, skb);
232 			continue;
233 		}
234 	}
235 
236 }
237 
238 static void ath_tx_flush_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
239 {
240 	struct ath_txq *txq = tid->ac->txq;
241 	struct sk_buff *skb;
242 	struct ath_buf *bf;
243 	struct list_head bf_head;
244 	struct ath_tx_status ts;
245 	struct ath_frame_info *fi;
246 	bool sendbar = false;
247 
248 	INIT_LIST_HEAD(&bf_head);
249 
250 	memset(&ts, 0, sizeof(ts));
251 
252 	while ((skb = __skb_dequeue(&tid->retry_q))) {
253 		fi = get_frame_info(skb);
254 		bf = fi->bf;
255 		if (!bf) {
256 			ath_txq_skb_done(sc, txq, skb);
257 			ieee80211_free_txskb(sc->hw, skb);
258 			continue;
259 		}
260 
261 		if (fi->baw_tracked) {
262 			ath_tx_update_baw(sc, tid, bf->bf_state.seqno);
263 			sendbar = true;
264 		}
265 
266 		list_add_tail(&bf->list, &bf_head);
267 		ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0);
268 	}
269 
270 	if (sendbar) {
271 		ath_txq_unlock(sc, txq);
272 		ath_send_bar(tid, tid->seq_start);
273 		ath_txq_lock(sc, txq);
274 	}
275 }
276 
277 static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
278 			      int seqno)
279 {
280 	int index, cindex;
281 
282 	index  = ATH_BA_INDEX(tid->seq_start, seqno);
283 	cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
284 
285 	__clear_bit(cindex, tid->tx_buf);
286 
287 	while (tid->baw_head != tid->baw_tail && !test_bit(tid->baw_head, tid->tx_buf)) {
288 		INCR(tid->seq_start, IEEE80211_SEQ_MAX);
289 		INCR(tid->baw_head, ATH_TID_MAX_BUFS);
290 		if (tid->bar_index >= 0)
291 			tid->bar_index--;
292 	}
293 }
294 
295 static void ath_tx_addto_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
296 			     struct ath_buf *bf)
297 {
298 	struct ath_frame_info *fi = get_frame_info(bf->bf_mpdu);
299 	u16 seqno = bf->bf_state.seqno;
300 	int index, cindex;
301 
302 	index  = ATH_BA_INDEX(tid->seq_start, seqno);
303 	cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
304 	__set_bit(cindex, tid->tx_buf);
305 	fi->baw_tracked = 1;
306 
307 	if (index >= ((tid->baw_tail - tid->baw_head) &
308 		(ATH_TID_MAX_BUFS - 1))) {
309 		tid->baw_tail = cindex;
310 		INCR(tid->baw_tail, ATH_TID_MAX_BUFS);
311 	}
312 }
313 
314 static void ath_tid_drain(struct ath_softc *sc, struct ath_txq *txq,
315 			  struct ath_atx_tid *tid)
316 
317 {
318 	struct sk_buff *skb;
319 	struct ath_buf *bf;
320 	struct list_head bf_head;
321 	struct ath_tx_status ts;
322 	struct ath_frame_info *fi;
323 
324 	memset(&ts, 0, sizeof(ts));
325 	INIT_LIST_HEAD(&bf_head);
326 
327 	while ((skb = ath_tid_dequeue(tid))) {
328 		fi = get_frame_info(skb);
329 		bf = fi->bf;
330 
331 		if (!bf) {
332 			ath_tx_complete(sc, skb, ATH_TX_ERROR, txq);
333 			continue;
334 		}
335 
336 		list_add_tail(&bf->list, &bf_head);
337 		ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0);
338 	}
339 }
340 
341 static void ath_tx_set_retry(struct ath_softc *sc, struct ath_txq *txq,
342 			     struct sk_buff *skb, int count)
343 {
344 	struct ath_frame_info *fi = get_frame_info(skb);
345 	struct ath_buf *bf = fi->bf;
346 	struct ieee80211_hdr *hdr;
347 	int prev = fi->retries;
348 
349 	TX_STAT_INC(txq->axq_qnum, a_retries);
350 	fi->retries += count;
351 
352 	if (prev > 0)
353 		return;
354 
355 	hdr = (struct ieee80211_hdr *)skb->data;
356 	hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_RETRY);
357 	dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
358 		sizeof(*hdr), DMA_TO_DEVICE);
359 }
360 
361 static struct ath_buf *ath_tx_get_buffer(struct ath_softc *sc)
362 {
363 	struct ath_buf *bf = NULL;
364 
365 	spin_lock_bh(&sc->tx.txbuflock);
366 
367 	if (unlikely(list_empty(&sc->tx.txbuf))) {
368 		spin_unlock_bh(&sc->tx.txbuflock);
369 		return NULL;
370 	}
371 
372 	bf = list_first_entry(&sc->tx.txbuf, struct ath_buf, list);
373 	list_del(&bf->list);
374 
375 	spin_unlock_bh(&sc->tx.txbuflock);
376 
377 	return bf;
378 }
379 
380 static void ath_tx_return_buffer(struct ath_softc *sc, struct ath_buf *bf)
381 {
382 	spin_lock_bh(&sc->tx.txbuflock);
383 	list_add_tail(&bf->list, &sc->tx.txbuf);
384 	spin_unlock_bh(&sc->tx.txbuflock);
385 }
386 
387 static struct ath_buf* ath_clone_txbuf(struct ath_softc *sc, struct ath_buf *bf)
388 {
389 	struct ath_buf *tbf;
390 
391 	tbf = ath_tx_get_buffer(sc);
392 	if (WARN_ON(!tbf))
393 		return NULL;
394 
395 	ATH_TXBUF_RESET(tbf);
396 
397 	tbf->bf_mpdu = bf->bf_mpdu;
398 	tbf->bf_buf_addr = bf->bf_buf_addr;
399 	memcpy(tbf->bf_desc, bf->bf_desc, sc->sc_ah->caps.tx_desc_len);
400 	tbf->bf_state = bf->bf_state;
401 	tbf->bf_state.stale = false;
402 
403 	return tbf;
404 }
405 
406 static void ath_tx_count_frames(struct ath_softc *sc, struct ath_buf *bf,
407 			        struct ath_tx_status *ts, int txok,
408 			        int *nframes, int *nbad)
409 {
410 	struct ath_frame_info *fi;
411 	u16 seq_st = 0;
412 	u32 ba[WME_BA_BMP_SIZE >> 5];
413 	int ba_index;
414 	int isaggr = 0;
415 
416 	*nbad = 0;
417 	*nframes = 0;
418 
419 	isaggr = bf_isaggr(bf);
420 	if (isaggr) {
421 		seq_st = ts->ts_seqnum;
422 		memcpy(ba, &ts->ba_low, WME_BA_BMP_SIZE >> 3);
423 	}
424 
425 	while (bf) {
426 		fi = get_frame_info(bf->bf_mpdu);
427 		ba_index = ATH_BA_INDEX(seq_st, bf->bf_state.seqno);
428 
429 		(*nframes)++;
430 		if (!txok || (isaggr && !ATH_BA_ISSET(ba, ba_index)))
431 			(*nbad)++;
432 
433 		bf = bf->bf_next;
434 	}
435 }
436 
437 
438 static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq,
439 				 struct ath_buf *bf, struct list_head *bf_q,
440 				 struct ath_tx_status *ts, int txok)
441 {
442 	struct ath_node *an = NULL;
443 	struct sk_buff *skb;
444 	struct ieee80211_sta *sta;
445 	struct ieee80211_hw *hw = sc->hw;
446 	struct ieee80211_hdr *hdr;
447 	struct ieee80211_tx_info *tx_info;
448 	struct ath_atx_tid *tid = NULL;
449 	struct ath_buf *bf_next, *bf_last = bf->bf_lastbf;
450 	struct list_head bf_head;
451 	struct sk_buff_head bf_pending;
452 	u16 seq_st = 0, acked_cnt = 0, txfail_cnt = 0, seq_first;
453 	u32 ba[WME_BA_BMP_SIZE >> 5];
454 	int isaggr, txfail, txpending, sendbar = 0, needreset = 0, nbad = 0;
455 	bool rc_update = true, isba;
456 	struct ieee80211_tx_rate rates[4];
457 	struct ath_frame_info *fi;
458 	int nframes;
459 	bool flush = !!(ts->ts_status & ATH9K_TX_FLUSH);
460 	int i, retries;
461 	int bar_index = -1;
462 
463 	skb = bf->bf_mpdu;
464 	hdr = (struct ieee80211_hdr *)skb->data;
465 
466 	tx_info = IEEE80211_SKB_CB(skb);
467 
468 	memcpy(rates, bf->rates, sizeof(rates));
469 
470 	retries = ts->ts_longretry + 1;
471 	for (i = 0; i < ts->ts_rateindex; i++)
472 		retries += rates[i].count;
473 
474 	rcu_read_lock();
475 
476 	sta = ieee80211_find_sta_by_ifaddr(hw, hdr->addr1, hdr->addr2);
477 	if (!sta) {
478 		rcu_read_unlock();
479 
480 		INIT_LIST_HEAD(&bf_head);
481 		while (bf) {
482 			bf_next = bf->bf_next;
483 
484 			if (!bf->bf_state.stale || bf_next != NULL)
485 				list_move_tail(&bf->list, &bf_head);
486 
487 			ath_tx_complete_buf(sc, bf, txq, &bf_head, ts, 0);
488 
489 			bf = bf_next;
490 		}
491 		return;
492 	}
493 
494 	an = (struct ath_node *)sta->drv_priv;
495 	tid = ath_get_skb_tid(sc, an, skb);
496 	seq_first = tid->seq_start;
497 	isba = ts->ts_flags & ATH9K_TX_BA;
498 
499 	/*
500 	 * The hardware occasionally sends a tx status for the wrong TID.
501 	 * In this case, the BA status cannot be considered valid and all
502 	 * subframes need to be retransmitted
503 	 *
504 	 * Only BlockAcks have a TID and therefore normal Acks cannot be
505 	 * checked
506 	 */
507 	if (isba && tid->tidno != ts->tid)
508 		txok = false;
509 
510 	isaggr = bf_isaggr(bf);
511 	memset(ba, 0, WME_BA_BMP_SIZE >> 3);
512 
513 	if (isaggr && txok) {
514 		if (ts->ts_flags & ATH9K_TX_BA) {
515 			seq_st = ts->ts_seqnum;
516 			memcpy(ba, &ts->ba_low, WME_BA_BMP_SIZE >> 3);
517 		} else {
518 			/*
519 			 * AR5416 can become deaf/mute when BA
520 			 * issue happens. Chip needs to be reset.
521 			 * But AP code may have sychronization issues
522 			 * when perform internal reset in this routine.
523 			 * Only enable reset in STA mode for now.
524 			 */
525 			if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION)
526 				needreset = 1;
527 		}
528 	}
529 
530 	__skb_queue_head_init(&bf_pending);
531 
532 	ath_tx_count_frames(sc, bf, ts, txok, &nframes, &nbad);
533 	while (bf) {
534 		u16 seqno = bf->bf_state.seqno;
535 
536 		txfail = txpending = sendbar = 0;
537 		bf_next = bf->bf_next;
538 
539 		skb = bf->bf_mpdu;
540 		tx_info = IEEE80211_SKB_CB(skb);
541 		fi = get_frame_info(skb);
542 
543 		if (!BAW_WITHIN(tid->seq_start, tid->baw_size, seqno) ||
544 		    !tid->active) {
545 			/*
546 			 * Outside of the current BlockAck window,
547 			 * maybe part of a previous session
548 			 */
549 			txfail = 1;
550 		} else if (ATH_BA_ISSET(ba, ATH_BA_INDEX(seq_st, seqno))) {
551 			/* transmit completion, subframe is
552 			 * acked by block ack */
553 			acked_cnt++;
554 		} else if (!isaggr && txok) {
555 			/* transmit completion */
556 			acked_cnt++;
557 		} else if (flush) {
558 			txpending = 1;
559 		} else if (fi->retries < ATH_MAX_SW_RETRIES) {
560 			if (txok || !an->sleeping)
561 				ath_tx_set_retry(sc, txq, bf->bf_mpdu,
562 						 retries);
563 
564 			txpending = 1;
565 		} else {
566 			txfail = 1;
567 			txfail_cnt++;
568 			bar_index = max_t(int, bar_index,
569 				ATH_BA_INDEX(seq_first, seqno));
570 		}
571 
572 		/*
573 		 * Make sure the last desc is reclaimed if it
574 		 * not a holding desc.
575 		 */
576 		INIT_LIST_HEAD(&bf_head);
577 		if (bf_next != NULL || !bf_last->bf_state.stale)
578 			list_move_tail(&bf->list, &bf_head);
579 
580 		if (!txpending) {
581 			/*
582 			 * complete the acked-ones/xretried ones; update
583 			 * block-ack window
584 			 */
585 			ath_tx_update_baw(sc, tid, seqno);
586 
587 			if (rc_update && (acked_cnt == 1 || txfail_cnt == 1)) {
588 				memcpy(tx_info->control.rates, rates, sizeof(rates));
589 				ath_tx_rc_status(sc, bf, ts, nframes, nbad, txok);
590 				rc_update = false;
591 				if (bf == bf->bf_lastbf)
592 					ath_dynack_sample_tx_ts(sc->sc_ah,
593 								bf->bf_mpdu,
594 								ts);
595 			}
596 
597 			ath_tx_complete_buf(sc, bf, txq, &bf_head, ts,
598 				!txfail);
599 		} else {
600 			if (tx_info->flags & IEEE80211_TX_STATUS_EOSP) {
601 				tx_info->flags &= ~IEEE80211_TX_STATUS_EOSP;
602 				ieee80211_sta_eosp(sta);
603 			}
604 			/* retry the un-acked ones */
605 			if (bf->bf_next == NULL && bf_last->bf_state.stale) {
606 				struct ath_buf *tbf;
607 
608 				tbf = ath_clone_txbuf(sc, bf_last);
609 				/*
610 				 * Update tx baw and complete the
611 				 * frame with failed status if we
612 				 * run out of tx buf.
613 				 */
614 				if (!tbf) {
615 					ath_tx_update_baw(sc, tid, seqno);
616 
617 					ath_tx_complete_buf(sc, bf, txq,
618 							    &bf_head, ts, 0);
619 					bar_index = max_t(int, bar_index,
620 						ATH_BA_INDEX(seq_first, seqno));
621 					break;
622 				}
623 
624 				fi->bf = tbf;
625 			}
626 
627 			/*
628 			 * Put this buffer to the temporary pending
629 			 * queue to retain ordering
630 			 */
631 			__skb_queue_tail(&bf_pending, skb);
632 		}
633 
634 		bf = bf_next;
635 	}
636 
637 	/* prepend un-acked frames to the beginning of the pending frame queue */
638 	if (!skb_queue_empty(&bf_pending)) {
639 		if (an->sleeping)
640 			ieee80211_sta_set_buffered(sta, tid->tidno, true);
641 
642 		skb_queue_splice_tail(&bf_pending, &tid->retry_q);
643 		if (!an->sleeping) {
644 			ath_tx_queue_tid(sc, txq, tid);
645 
646 			if (ts->ts_status & (ATH9K_TXERR_FILT | ATH9K_TXERR_XRETRY))
647 				tid->ac->clear_ps_filter = true;
648 		}
649 	}
650 
651 	if (bar_index >= 0) {
652 		u16 bar_seq = ATH_BA_INDEX2SEQ(seq_first, bar_index);
653 
654 		if (BAW_WITHIN(tid->seq_start, tid->baw_size, bar_seq))
655 			tid->bar_index = ATH_BA_INDEX(tid->seq_start, bar_seq);
656 
657 		ath_txq_unlock(sc, txq);
658 		ath_send_bar(tid, ATH_BA_INDEX2SEQ(seq_first, bar_index + 1));
659 		ath_txq_lock(sc, txq);
660 	}
661 
662 	rcu_read_unlock();
663 
664 	if (needreset)
665 		ath9k_queue_reset(sc, RESET_TYPE_TX_ERROR);
666 }
667 
668 static bool bf_is_ampdu_not_probing(struct ath_buf *bf)
669 {
670     struct ieee80211_tx_info *info = IEEE80211_SKB_CB(bf->bf_mpdu);
671     return bf_isampdu(bf) && !(info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE);
672 }
673 
674 static void ath_tx_process_buffer(struct ath_softc *sc, struct ath_txq *txq,
675 				  struct ath_tx_status *ts, struct ath_buf *bf,
676 				  struct list_head *bf_head)
677 {
678 	struct ieee80211_tx_info *info;
679 	bool txok, flush;
680 
681 	txok = !(ts->ts_status & ATH9K_TXERR_MASK);
682 	flush = !!(ts->ts_status & ATH9K_TX_FLUSH);
683 	txq->axq_tx_inprogress = false;
684 
685 	txq->axq_depth--;
686 	if (bf_is_ampdu_not_probing(bf))
687 		txq->axq_ampdu_depth--;
688 
689 	ts->duration = ath9k_hw_get_duration(sc->sc_ah, bf->bf_desc,
690 					     ts->ts_rateindex);
691 	if (!bf_isampdu(bf)) {
692 		if (!flush) {
693 			info = IEEE80211_SKB_CB(bf->bf_mpdu);
694 			memcpy(info->control.rates, bf->rates,
695 			       sizeof(info->control.rates));
696 			ath_tx_rc_status(sc, bf, ts, 1, txok ? 0 : 1, txok);
697 			ath_dynack_sample_tx_ts(sc->sc_ah, bf->bf_mpdu, ts);
698 		}
699 		ath_tx_complete_buf(sc, bf, txq, bf_head, ts, txok);
700 	} else
701 		ath_tx_complete_aggr(sc, txq, bf, bf_head, ts, txok);
702 
703 	if (!flush)
704 		ath_txq_schedule(sc, txq);
705 }
706 
707 static bool ath_lookup_legacy(struct ath_buf *bf)
708 {
709 	struct sk_buff *skb;
710 	struct ieee80211_tx_info *tx_info;
711 	struct ieee80211_tx_rate *rates;
712 	int i;
713 
714 	skb = bf->bf_mpdu;
715 	tx_info = IEEE80211_SKB_CB(skb);
716 	rates = tx_info->control.rates;
717 
718 	for (i = 0; i < 4; i++) {
719 		if (!rates[i].count || rates[i].idx < 0)
720 			break;
721 
722 		if (!(rates[i].flags & IEEE80211_TX_RC_MCS))
723 			return true;
724 	}
725 
726 	return false;
727 }
728 
729 static u32 ath_lookup_rate(struct ath_softc *sc, struct ath_buf *bf,
730 			   struct ath_atx_tid *tid)
731 {
732 	struct sk_buff *skb;
733 	struct ieee80211_tx_info *tx_info;
734 	struct ieee80211_tx_rate *rates;
735 	u32 max_4ms_framelen, frmlen;
736 	u16 aggr_limit, bt_aggr_limit, legacy = 0;
737 	int q = tid->ac->txq->mac80211_qnum;
738 	int i;
739 
740 	skb = bf->bf_mpdu;
741 	tx_info = IEEE80211_SKB_CB(skb);
742 	rates = bf->rates;
743 
744 	/*
745 	 * Find the lowest frame length among the rate series that will have a
746 	 * 4ms (or TXOP limited) transmit duration.
747 	 */
748 	max_4ms_framelen = ATH_AMPDU_LIMIT_MAX;
749 
750 	for (i = 0; i < 4; i++) {
751 		int modeidx;
752 
753 		if (!rates[i].count)
754 			continue;
755 
756 		if (!(rates[i].flags & IEEE80211_TX_RC_MCS)) {
757 			legacy = 1;
758 			break;
759 		}
760 
761 		if (rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
762 			modeidx = MCS_HT40;
763 		else
764 			modeidx = MCS_HT20;
765 
766 		if (rates[i].flags & IEEE80211_TX_RC_SHORT_GI)
767 			modeidx++;
768 
769 		frmlen = sc->tx.max_aggr_framelen[q][modeidx][rates[i].idx];
770 		max_4ms_framelen = min(max_4ms_framelen, frmlen);
771 	}
772 
773 	/*
774 	 * limit aggregate size by the minimum rate if rate selected is
775 	 * not a probe rate, if rate selected is a probe rate then
776 	 * avoid aggregation of this packet.
777 	 */
778 	if (tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE || legacy)
779 		return 0;
780 
781 	aggr_limit = min(max_4ms_framelen, (u32)ATH_AMPDU_LIMIT_MAX);
782 
783 	/*
784 	 * Override the default aggregation limit for BTCOEX.
785 	 */
786 	bt_aggr_limit = ath9k_btcoex_aggr_limit(sc, max_4ms_framelen);
787 	if (bt_aggr_limit)
788 		aggr_limit = bt_aggr_limit;
789 
790 	if (tid->an->maxampdu)
791 		aggr_limit = min(aggr_limit, tid->an->maxampdu);
792 
793 	return aggr_limit;
794 }
795 
796 /*
797  * Returns the number of delimiters to be added to
798  * meet the minimum required mpdudensity.
799  */
800 static int ath_compute_num_delims(struct ath_softc *sc, struct ath_atx_tid *tid,
801 				  struct ath_buf *bf, u16 frmlen,
802 				  bool first_subfrm)
803 {
804 #define FIRST_DESC_NDELIMS 60
805 	u32 nsymbits, nsymbols;
806 	u16 minlen;
807 	u8 flags, rix;
808 	int width, streams, half_gi, ndelim, mindelim;
809 	struct ath_frame_info *fi = get_frame_info(bf->bf_mpdu);
810 
811 	/* Select standard number of delimiters based on frame length alone */
812 	ndelim = ATH_AGGR_GET_NDELIM(frmlen);
813 
814 	/*
815 	 * If encryption enabled, hardware requires some more padding between
816 	 * subframes.
817 	 * TODO - this could be improved to be dependent on the rate.
818 	 *      The hardware can keep up at lower rates, but not higher rates
819 	 */
820 	if ((fi->keyix != ATH9K_TXKEYIX_INVALID) &&
821 	    !(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA))
822 		ndelim += ATH_AGGR_ENCRYPTDELIM;
823 
824 	/*
825 	 * Add delimiter when using RTS/CTS with aggregation
826 	 * and non enterprise AR9003 card
827 	 */
828 	if (first_subfrm && !AR_SREV_9580_10_OR_LATER(sc->sc_ah) &&
829 	    (sc->sc_ah->ent_mode & AR_ENT_OTP_MIN_PKT_SIZE_DISABLE))
830 		ndelim = max(ndelim, FIRST_DESC_NDELIMS);
831 
832 	/*
833 	 * Convert desired mpdu density from microeconds to bytes based
834 	 * on highest rate in rate series (i.e. first rate) to determine
835 	 * required minimum length for subframe. Take into account
836 	 * whether high rate is 20 or 40Mhz and half or full GI.
837 	 *
838 	 * If there is no mpdu density restriction, no further calculation
839 	 * is needed.
840 	 */
841 
842 	if (tid->an->mpdudensity == 0)
843 		return ndelim;
844 
845 	rix = bf->rates[0].idx;
846 	flags = bf->rates[0].flags;
847 	width = (flags & IEEE80211_TX_RC_40_MHZ_WIDTH) ? 1 : 0;
848 	half_gi = (flags & IEEE80211_TX_RC_SHORT_GI) ? 1 : 0;
849 
850 	if (half_gi)
851 		nsymbols = NUM_SYMBOLS_PER_USEC_HALFGI(tid->an->mpdudensity);
852 	else
853 		nsymbols = NUM_SYMBOLS_PER_USEC(tid->an->mpdudensity);
854 
855 	if (nsymbols == 0)
856 		nsymbols = 1;
857 
858 	streams = HT_RC_2_STREAMS(rix);
859 	nsymbits = bits_per_symbol[rix % 8][width] * streams;
860 	minlen = (nsymbols * nsymbits) / BITS_PER_BYTE;
861 
862 	if (frmlen < minlen) {
863 		mindelim = (minlen - frmlen) / ATH_AGGR_DELIM_SZ;
864 		ndelim = max(mindelim, ndelim);
865 	}
866 
867 	return ndelim;
868 }
869 
870 static struct ath_buf *
871 ath_tx_get_tid_subframe(struct ath_softc *sc, struct ath_txq *txq,
872 			struct ath_atx_tid *tid, struct sk_buff_head **q)
873 {
874 	struct ieee80211_tx_info *tx_info;
875 	struct ath_frame_info *fi;
876 	struct sk_buff *skb;
877 	struct ath_buf *bf;
878 	u16 seqno;
879 
880 	while (1) {
881 		*q = &tid->retry_q;
882 		if (skb_queue_empty(*q))
883 			*q = &tid->buf_q;
884 
885 		skb = skb_peek(*q);
886 		if (!skb)
887 			break;
888 
889 		fi = get_frame_info(skb);
890 		bf = fi->bf;
891 		if (!fi->bf)
892 			bf = ath_tx_setup_buffer(sc, txq, tid, skb);
893 		else
894 			bf->bf_state.stale = false;
895 
896 		if (!bf) {
897 			__skb_unlink(skb, *q);
898 			ath_txq_skb_done(sc, txq, skb);
899 			ieee80211_free_txskb(sc->hw, skb);
900 			continue;
901 		}
902 
903 		bf->bf_next = NULL;
904 		bf->bf_lastbf = bf;
905 
906 		tx_info = IEEE80211_SKB_CB(skb);
907 		tx_info->flags &= ~IEEE80211_TX_CTL_CLEAR_PS_FILT;
908 
909 		/*
910 		 * No aggregation session is running, but there may be frames
911 		 * from a previous session or a failed attempt in the queue.
912 		 * Send them out as normal data frames
913 		 */
914 		if (!tid->active)
915 			tx_info->flags &= ~IEEE80211_TX_CTL_AMPDU;
916 
917 		if (!(tx_info->flags & IEEE80211_TX_CTL_AMPDU)) {
918 			bf->bf_state.bf_type = 0;
919 			return bf;
920 		}
921 
922 		bf->bf_state.bf_type = BUF_AMPDU | BUF_AGGR;
923 		seqno = bf->bf_state.seqno;
924 
925 		/* do not step over block-ack window */
926 		if (!BAW_WITHIN(tid->seq_start, tid->baw_size, seqno))
927 			break;
928 
929 		if (tid->bar_index > ATH_BA_INDEX(tid->seq_start, seqno)) {
930 			struct ath_tx_status ts = {};
931 			struct list_head bf_head;
932 
933 			INIT_LIST_HEAD(&bf_head);
934 			list_add(&bf->list, &bf_head);
935 			__skb_unlink(skb, *q);
936 			ath_tx_update_baw(sc, tid, seqno);
937 			ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0);
938 			continue;
939 		}
940 
941 		return bf;
942 	}
943 
944 	return NULL;
945 }
946 
947 static bool
948 ath_tx_form_aggr(struct ath_softc *sc, struct ath_txq *txq,
949 		 struct ath_atx_tid *tid, struct list_head *bf_q,
950 		 struct ath_buf *bf_first, struct sk_buff_head *tid_q,
951 		 int *aggr_len)
952 {
953 #define PADBYTES(_len) ((4 - ((_len) % 4)) % 4)
954 	struct ath_buf *bf = bf_first, *bf_prev = NULL;
955 	int nframes = 0, ndelim;
956 	u16 aggr_limit = 0, al = 0, bpad = 0,
957 	    al_delta, h_baw = tid->baw_size / 2;
958 	struct ieee80211_tx_info *tx_info;
959 	struct ath_frame_info *fi;
960 	struct sk_buff *skb;
961 	bool closed = false;
962 
963 	bf = bf_first;
964 	aggr_limit = ath_lookup_rate(sc, bf, tid);
965 
966 	do {
967 		skb = bf->bf_mpdu;
968 		fi = get_frame_info(skb);
969 
970 		/* do not exceed aggregation limit */
971 		al_delta = ATH_AGGR_DELIM_SZ + fi->framelen;
972 		if (nframes) {
973 			if (aggr_limit < al + bpad + al_delta ||
974 			    ath_lookup_legacy(bf) || nframes >= h_baw)
975 				break;
976 
977 			tx_info = IEEE80211_SKB_CB(bf->bf_mpdu);
978 			if ((tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) ||
979 			    !(tx_info->flags & IEEE80211_TX_CTL_AMPDU))
980 				break;
981 		}
982 
983 		/* add padding for previous frame to aggregation length */
984 		al += bpad + al_delta;
985 
986 		/*
987 		 * Get the delimiters needed to meet the MPDU
988 		 * density for this node.
989 		 */
990 		ndelim = ath_compute_num_delims(sc, tid, bf_first, fi->framelen,
991 						!nframes);
992 		bpad = PADBYTES(al_delta) + (ndelim << 2);
993 
994 		nframes++;
995 		bf->bf_next = NULL;
996 
997 		/* link buffers of this frame to the aggregate */
998 		if (!fi->baw_tracked)
999 			ath_tx_addto_baw(sc, tid, bf);
1000 		bf->bf_state.ndelim = ndelim;
1001 
1002 		__skb_unlink(skb, tid_q);
1003 		list_add_tail(&bf->list, bf_q);
1004 		if (bf_prev)
1005 			bf_prev->bf_next = bf;
1006 
1007 		bf_prev = bf;
1008 
1009 		bf = ath_tx_get_tid_subframe(sc, txq, tid, &tid_q);
1010 		if (!bf) {
1011 			closed = true;
1012 			break;
1013 		}
1014 	} while (ath_tid_has_buffered(tid));
1015 
1016 	bf = bf_first;
1017 	bf->bf_lastbf = bf_prev;
1018 
1019 	if (bf == bf_prev) {
1020 		al = get_frame_info(bf->bf_mpdu)->framelen;
1021 		bf->bf_state.bf_type = BUF_AMPDU;
1022 	} else {
1023 		TX_STAT_INC(txq->axq_qnum, a_aggr);
1024 	}
1025 
1026 	*aggr_len = al;
1027 
1028 	return closed;
1029 #undef PADBYTES
1030 }
1031 
1032 /*
1033  * rix - rate index
1034  * pktlen - total bytes (delims + data + fcs + pads + pad delims)
1035  * width  - 0 for 20 MHz, 1 for 40 MHz
1036  * half_gi - to use 4us v/s 3.6 us for symbol time
1037  */
1038 static u32 ath_pkt_duration(struct ath_softc *sc, u8 rix, int pktlen,
1039 			    int width, int half_gi, bool shortPreamble)
1040 {
1041 	u32 nbits, nsymbits, duration, nsymbols;
1042 	int streams;
1043 
1044 	/* find number of symbols: PLCP + data */
1045 	streams = HT_RC_2_STREAMS(rix);
1046 	nbits = (pktlen << 3) + OFDM_PLCP_BITS;
1047 	nsymbits = bits_per_symbol[rix % 8][width] * streams;
1048 	nsymbols = (nbits + nsymbits - 1) / nsymbits;
1049 
1050 	if (!half_gi)
1051 		duration = SYMBOL_TIME(nsymbols);
1052 	else
1053 		duration = SYMBOL_TIME_HALFGI(nsymbols);
1054 
1055 	/* addup duration for legacy/ht training and signal fields */
1056 	duration += L_STF + L_LTF + L_SIG + HT_SIG + HT_STF + HT_LTF(streams);
1057 
1058 	return duration;
1059 }
1060 
1061 static int ath_max_framelen(int usec, int mcs, bool ht40, bool sgi)
1062 {
1063 	int streams = HT_RC_2_STREAMS(mcs);
1064 	int symbols, bits;
1065 	int bytes = 0;
1066 
1067 	usec -= L_STF + L_LTF + L_SIG + HT_SIG + HT_STF + HT_LTF(streams);
1068 	symbols = sgi ? TIME_SYMBOLS_HALFGI(usec) : TIME_SYMBOLS(usec);
1069 	bits = symbols * bits_per_symbol[mcs % 8][ht40] * streams;
1070 	bits -= OFDM_PLCP_BITS;
1071 	bytes = bits / 8;
1072 	if (bytes > 65532)
1073 		bytes = 65532;
1074 
1075 	return bytes;
1076 }
1077 
1078 void ath_update_max_aggr_framelen(struct ath_softc *sc, int queue, int txop)
1079 {
1080 	u16 *cur_ht20, *cur_ht20_sgi, *cur_ht40, *cur_ht40_sgi;
1081 	int mcs;
1082 
1083 	/* 4ms is the default (and maximum) duration */
1084 	if (!txop || txop > 4096)
1085 		txop = 4096;
1086 
1087 	cur_ht20 = sc->tx.max_aggr_framelen[queue][MCS_HT20];
1088 	cur_ht20_sgi = sc->tx.max_aggr_framelen[queue][MCS_HT20_SGI];
1089 	cur_ht40 = sc->tx.max_aggr_framelen[queue][MCS_HT40];
1090 	cur_ht40_sgi = sc->tx.max_aggr_framelen[queue][MCS_HT40_SGI];
1091 	for (mcs = 0; mcs < 32; mcs++) {
1092 		cur_ht20[mcs] = ath_max_framelen(txop, mcs, false, false);
1093 		cur_ht20_sgi[mcs] = ath_max_framelen(txop, mcs, false, true);
1094 		cur_ht40[mcs] = ath_max_framelen(txop, mcs, true, false);
1095 		cur_ht40_sgi[mcs] = ath_max_framelen(txop, mcs, true, true);
1096 	}
1097 }
1098 
1099 static u8 ath_get_rate_txpower(struct ath_softc *sc, struct ath_buf *bf,
1100 			       u8 rateidx, bool is_40, bool is_cck)
1101 {
1102 	u8 max_power;
1103 	struct sk_buff *skb;
1104 	struct ath_frame_info *fi;
1105 	struct ieee80211_tx_info *info;
1106 	struct ath_hw *ah = sc->sc_ah;
1107 
1108 	if (sc->tx99_state || !ah->tpc_enabled)
1109 		return MAX_RATE_POWER;
1110 
1111 	skb = bf->bf_mpdu;
1112 	fi = get_frame_info(skb);
1113 	info = IEEE80211_SKB_CB(skb);
1114 
1115 	if (!AR_SREV_9300_20_OR_LATER(ah)) {
1116 		int txpower = fi->tx_power;
1117 
1118 		if (is_40) {
1119 			u8 power_ht40delta;
1120 			struct ar5416_eeprom_def *eep = &ah->eeprom.def;
1121 
1122 			if (AR5416_VER_MASK >= AR5416_EEP_MINOR_VER_2) {
1123 				bool is_2ghz;
1124 				struct modal_eep_header *pmodal;
1125 
1126 				is_2ghz = info->band == IEEE80211_BAND_2GHZ;
1127 				pmodal = &eep->modalHeader[is_2ghz];
1128 				power_ht40delta = pmodal->ht40PowerIncForPdadc;
1129 			} else {
1130 				power_ht40delta = 2;
1131 			}
1132 			txpower += power_ht40delta;
1133 		}
1134 
1135 		if (AR_SREV_9287(ah) || AR_SREV_9285(ah) ||
1136 		    AR_SREV_9271(ah)) {
1137 			txpower -= 2 * AR9287_PWR_TABLE_OFFSET_DB;
1138 		} else if (AR_SREV_9280_20_OR_LATER(ah)) {
1139 			s8 power_offset;
1140 
1141 			power_offset = ah->eep_ops->get_eeprom(ah,
1142 							EEP_PWR_TABLE_OFFSET);
1143 			txpower -= 2 * power_offset;
1144 		}
1145 
1146 		if (OLC_FOR_AR9280_20_LATER && is_cck)
1147 			txpower -= 2;
1148 
1149 		txpower = max(txpower, 0);
1150 		max_power = min_t(u8, ah->tx_power[rateidx], txpower);
1151 
1152 		/* XXX: clamp minimum TX power at 1 for AR9160 since if
1153 		 * max_power is set to 0, frames are transmitted at max
1154 		 * TX power
1155 		 */
1156 		if (!max_power && !AR_SREV_9280_20_OR_LATER(ah))
1157 			max_power = 1;
1158 	} else if (!bf->bf_state.bfs_paprd) {
1159 		if (rateidx < 8 && (info->flags & IEEE80211_TX_CTL_STBC))
1160 			max_power = min(ah->tx_power_stbc[rateidx],
1161 					fi->tx_power);
1162 		else
1163 			max_power = min(ah->tx_power[rateidx], fi->tx_power);
1164 	} else {
1165 		max_power = ah->paprd_training_power;
1166 	}
1167 
1168 	return max_power;
1169 }
1170 
1171 static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf,
1172 			     struct ath_tx_info *info, int len, bool rts)
1173 {
1174 	struct ath_hw *ah = sc->sc_ah;
1175 	struct ath_common *common = ath9k_hw_common(ah);
1176 	struct sk_buff *skb;
1177 	struct ieee80211_tx_info *tx_info;
1178 	struct ieee80211_tx_rate *rates;
1179 	const struct ieee80211_rate *rate;
1180 	struct ieee80211_hdr *hdr;
1181 	struct ath_frame_info *fi = get_frame_info(bf->bf_mpdu);
1182 	u32 rts_thresh = sc->hw->wiphy->rts_threshold;
1183 	int i;
1184 	u8 rix = 0;
1185 
1186 	skb = bf->bf_mpdu;
1187 	tx_info = IEEE80211_SKB_CB(skb);
1188 	rates = bf->rates;
1189 	hdr = (struct ieee80211_hdr *)skb->data;
1190 
1191 	/* set dur_update_en for l-sig computation except for PS-Poll frames */
1192 	info->dur_update = !ieee80211_is_pspoll(hdr->frame_control);
1193 	info->rtscts_rate = fi->rtscts_rate;
1194 
1195 	for (i = 0; i < ARRAY_SIZE(bf->rates); i++) {
1196 		bool is_40, is_sgi, is_sp, is_cck;
1197 		int phy;
1198 
1199 		if (!rates[i].count || (rates[i].idx < 0))
1200 			continue;
1201 
1202 		rix = rates[i].idx;
1203 		info->rates[i].Tries = rates[i].count;
1204 
1205 		/*
1206 		 * Handle RTS threshold for unaggregated HT frames.
1207 		 */
1208 		if (bf_isampdu(bf) && !bf_isaggr(bf) &&
1209 		    (rates[i].flags & IEEE80211_TX_RC_MCS) &&
1210 		    unlikely(rts_thresh != (u32) -1)) {
1211 			if (!rts_thresh || (len > rts_thresh))
1212 				rts = true;
1213 		}
1214 
1215 		if (rts || rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) {
1216 			info->rates[i].RateFlags |= ATH9K_RATESERIES_RTS_CTS;
1217 			info->flags |= ATH9K_TXDESC_RTSENA;
1218 		} else if (rates[i].flags & IEEE80211_TX_RC_USE_CTS_PROTECT) {
1219 			info->rates[i].RateFlags |= ATH9K_RATESERIES_RTS_CTS;
1220 			info->flags |= ATH9K_TXDESC_CTSENA;
1221 		}
1222 
1223 		if (rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
1224 			info->rates[i].RateFlags |= ATH9K_RATESERIES_2040;
1225 		if (rates[i].flags & IEEE80211_TX_RC_SHORT_GI)
1226 			info->rates[i].RateFlags |= ATH9K_RATESERIES_HALFGI;
1227 
1228 		is_sgi = !!(rates[i].flags & IEEE80211_TX_RC_SHORT_GI);
1229 		is_40 = !!(rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH);
1230 		is_sp = !!(rates[i].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
1231 
1232 		if (rates[i].flags & IEEE80211_TX_RC_MCS) {
1233 			/* MCS rates */
1234 			info->rates[i].Rate = rix | 0x80;
1235 			info->rates[i].ChSel = ath_txchainmask_reduction(sc,
1236 					ah->txchainmask, info->rates[i].Rate);
1237 			info->rates[i].PktDuration = ath_pkt_duration(sc, rix, len,
1238 				 is_40, is_sgi, is_sp);
1239 			if (rix < 8 && (tx_info->flags & IEEE80211_TX_CTL_STBC))
1240 				info->rates[i].RateFlags |= ATH9K_RATESERIES_STBC;
1241 
1242 			info->txpower[i] = ath_get_rate_txpower(sc, bf, rix,
1243 								is_40, false);
1244 			continue;
1245 		}
1246 
1247 		/* legacy rates */
1248 		rate = &common->sbands[tx_info->band].bitrates[rates[i].idx];
1249 		if ((tx_info->band == IEEE80211_BAND_2GHZ) &&
1250 		    !(rate->flags & IEEE80211_RATE_ERP_G))
1251 			phy = WLAN_RC_PHY_CCK;
1252 		else
1253 			phy = WLAN_RC_PHY_OFDM;
1254 
1255 		info->rates[i].Rate = rate->hw_value;
1256 		if (rate->hw_value_short) {
1257 			if (rates[i].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
1258 				info->rates[i].Rate |= rate->hw_value_short;
1259 		} else {
1260 			is_sp = false;
1261 		}
1262 
1263 		if (bf->bf_state.bfs_paprd)
1264 			info->rates[i].ChSel = ah->txchainmask;
1265 		else
1266 			info->rates[i].ChSel = ath_txchainmask_reduction(sc,
1267 					ah->txchainmask, info->rates[i].Rate);
1268 
1269 		info->rates[i].PktDuration = ath9k_hw_computetxtime(sc->sc_ah,
1270 			phy, rate->bitrate * 100, len, rix, is_sp);
1271 
1272 		is_cck = IS_CCK_RATE(info->rates[i].Rate);
1273 		info->txpower[i] = ath_get_rate_txpower(sc, bf, rix, false,
1274 							is_cck);
1275 	}
1276 
1277 	/* For AR5416 - RTS cannot be followed by a frame larger than 8K */
1278 	if (bf_isaggr(bf) && (len > sc->sc_ah->caps.rts_aggr_limit))
1279 		info->flags &= ~ATH9K_TXDESC_RTSENA;
1280 
1281 	/* ATH9K_TXDESC_RTSENA and ATH9K_TXDESC_CTSENA are mutually exclusive. */
1282 	if (info->flags & ATH9K_TXDESC_RTSENA)
1283 		info->flags &= ~ATH9K_TXDESC_CTSENA;
1284 }
1285 
1286 static enum ath9k_pkt_type get_hw_packet_type(struct sk_buff *skb)
1287 {
1288 	struct ieee80211_hdr *hdr;
1289 	enum ath9k_pkt_type htype;
1290 	__le16 fc;
1291 
1292 	hdr = (struct ieee80211_hdr *)skb->data;
1293 	fc = hdr->frame_control;
1294 
1295 	if (ieee80211_is_beacon(fc))
1296 		htype = ATH9K_PKT_TYPE_BEACON;
1297 	else if (ieee80211_is_probe_resp(fc))
1298 		htype = ATH9K_PKT_TYPE_PROBE_RESP;
1299 	else if (ieee80211_is_atim(fc))
1300 		htype = ATH9K_PKT_TYPE_ATIM;
1301 	else if (ieee80211_is_pspoll(fc))
1302 		htype = ATH9K_PKT_TYPE_PSPOLL;
1303 	else
1304 		htype = ATH9K_PKT_TYPE_NORMAL;
1305 
1306 	return htype;
1307 }
1308 
1309 static void ath_tx_fill_desc(struct ath_softc *sc, struct ath_buf *bf,
1310 			     struct ath_txq *txq, int len)
1311 {
1312 	struct ath_hw *ah = sc->sc_ah;
1313 	struct ath_buf *bf_first = NULL;
1314 	struct ath_tx_info info;
1315 	u32 rts_thresh = sc->hw->wiphy->rts_threshold;
1316 	bool rts = false;
1317 
1318 	memset(&info, 0, sizeof(info));
1319 	info.is_first = true;
1320 	info.is_last = true;
1321 	info.qcu = txq->axq_qnum;
1322 
1323 	while (bf) {
1324 		struct sk_buff *skb = bf->bf_mpdu;
1325 		struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1326 		struct ath_frame_info *fi = get_frame_info(skb);
1327 		bool aggr = !!(bf->bf_state.bf_type & BUF_AGGR);
1328 
1329 		info.type = get_hw_packet_type(skb);
1330 		if (bf->bf_next)
1331 			info.link = bf->bf_next->bf_daddr;
1332 		else
1333 			info.link = (sc->tx99_state) ? bf->bf_daddr : 0;
1334 
1335 		if (!bf_first) {
1336 			bf_first = bf;
1337 
1338 			if (!sc->tx99_state)
1339 				info.flags = ATH9K_TXDESC_INTREQ;
1340 			if ((tx_info->flags & IEEE80211_TX_CTL_CLEAR_PS_FILT) ||
1341 			    txq == sc->tx.uapsdq)
1342 				info.flags |= ATH9K_TXDESC_CLRDMASK;
1343 
1344 			if (tx_info->flags & IEEE80211_TX_CTL_NO_ACK)
1345 				info.flags |= ATH9K_TXDESC_NOACK;
1346 			if (tx_info->flags & IEEE80211_TX_CTL_LDPC)
1347 				info.flags |= ATH9K_TXDESC_LDPC;
1348 
1349 			if (bf->bf_state.bfs_paprd)
1350 				info.flags |= (u32) bf->bf_state.bfs_paprd <<
1351 					      ATH9K_TXDESC_PAPRD_S;
1352 
1353 			/*
1354 			 * mac80211 doesn't handle RTS threshold for HT because
1355 			 * the decision has to be taken based on AMPDU length
1356 			 * and aggregation is done entirely inside ath9k.
1357 			 * Set the RTS/CTS flag for the first subframe based
1358 			 * on the threshold.
1359 			 */
1360 			if (aggr && (bf == bf_first) &&
1361 			    unlikely(rts_thresh != (u32) -1)) {
1362 				/*
1363 				 * "len" is the size of the entire AMPDU.
1364 				 */
1365 				if (!rts_thresh || (len > rts_thresh))
1366 					rts = true;
1367 			}
1368 
1369 			if (!aggr)
1370 				len = fi->framelen;
1371 
1372 			ath_buf_set_rate(sc, bf, &info, len, rts);
1373 		}
1374 
1375 		info.buf_addr[0] = bf->bf_buf_addr;
1376 		info.buf_len[0] = skb->len;
1377 		info.pkt_len = fi->framelen;
1378 		info.keyix = fi->keyix;
1379 		info.keytype = fi->keytype;
1380 
1381 		if (aggr) {
1382 			if (bf == bf_first)
1383 				info.aggr = AGGR_BUF_FIRST;
1384 			else if (bf == bf_first->bf_lastbf)
1385 				info.aggr = AGGR_BUF_LAST;
1386 			else
1387 				info.aggr = AGGR_BUF_MIDDLE;
1388 
1389 			info.ndelim = bf->bf_state.ndelim;
1390 			info.aggr_len = len;
1391 		}
1392 
1393 		if (bf == bf_first->bf_lastbf)
1394 			bf_first = NULL;
1395 
1396 		ath9k_hw_set_txdesc(ah, bf->bf_desc, &info);
1397 		bf = bf->bf_next;
1398 	}
1399 }
1400 
1401 static void
1402 ath_tx_form_burst(struct ath_softc *sc, struct ath_txq *txq,
1403 		  struct ath_atx_tid *tid, struct list_head *bf_q,
1404 		  struct ath_buf *bf_first, struct sk_buff_head *tid_q)
1405 {
1406 	struct ath_buf *bf = bf_first, *bf_prev = NULL;
1407 	struct sk_buff *skb;
1408 	int nframes = 0;
1409 
1410 	do {
1411 		struct ieee80211_tx_info *tx_info;
1412 		skb = bf->bf_mpdu;
1413 
1414 		nframes++;
1415 		__skb_unlink(skb, tid_q);
1416 		list_add_tail(&bf->list, bf_q);
1417 		if (bf_prev)
1418 			bf_prev->bf_next = bf;
1419 		bf_prev = bf;
1420 
1421 		if (nframes >= 2)
1422 			break;
1423 
1424 		bf = ath_tx_get_tid_subframe(sc, txq, tid, &tid_q);
1425 		if (!bf)
1426 			break;
1427 
1428 		tx_info = IEEE80211_SKB_CB(bf->bf_mpdu);
1429 		if (tx_info->flags & IEEE80211_TX_CTL_AMPDU)
1430 			break;
1431 
1432 		ath_set_rates(tid->an->vif, tid->an->sta, bf);
1433 	} while (1);
1434 }
1435 
1436 static bool ath_tx_sched_aggr(struct ath_softc *sc, struct ath_txq *txq,
1437 			      struct ath_atx_tid *tid, bool *stop)
1438 {
1439 	struct ath_buf *bf;
1440 	struct ieee80211_tx_info *tx_info;
1441 	struct sk_buff_head *tid_q;
1442 	struct list_head bf_q;
1443 	int aggr_len = 0;
1444 	bool aggr, last = true;
1445 
1446 	if (!ath_tid_has_buffered(tid))
1447 		return false;
1448 
1449 	INIT_LIST_HEAD(&bf_q);
1450 
1451 	bf = ath_tx_get_tid_subframe(sc, txq, tid, &tid_q);
1452 	if (!bf)
1453 		return false;
1454 
1455 	tx_info = IEEE80211_SKB_CB(bf->bf_mpdu);
1456 	aggr = !!(tx_info->flags & IEEE80211_TX_CTL_AMPDU);
1457 	if ((aggr && txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH) ||
1458 		(!aggr && txq->axq_depth >= ATH_NON_AGGR_MIN_QDEPTH)) {
1459 		*stop = true;
1460 		return false;
1461 	}
1462 
1463 	ath_set_rates(tid->an->vif, tid->an->sta, bf);
1464 	if (aggr)
1465 		last = ath_tx_form_aggr(sc, txq, tid, &bf_q, bf,
1466 					tid_q, &aggr_len);
1467 	else
1468 		ath_tx_form_burst(sc, txq, tid, &bf_q, bf, tid_q);
1469 
1470 	if (list_empty(&bf_q))
1471 		return false;
1472 
1473 	if (tid->ac->clear_ps_filter || tid->an->no_ps_filter) {
1474 		tid->ac->clear_ps_filter = false;
1475 		tx_info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1476 	}
1477 
1478 	ath_tx_fill_desc(sc, bf, txq, aggr_len);
1479 	ath_tx_txqaddbuf(sc, txq, &bf_q, false);
1480 	return true;
1481 }
1482 
1483 int ath_tx_aggr_start(struct ath_softc *sc, struct ieee80211_sta *sta,
1484 		      u16 tid, u16 *ssn)
1485 {
1486 	struct ath_atx_tid *txtid;
1487 	struct ath_txq *txq;
1488 	struct ath_node *an;
1489 	u8 density;
1490 
1491 	an = (struct ath_node *)sta->drv_priv;
1492 	txtid = ATH_AN_2_TID(an, tid);
1493 	txq = txtid->ac->txq;
1494 
1495 	ath_txq_lock(sc, txq);
1496 
1497 	/* update ampdu factor/density, they may have changed. This may happen
1498 	 * in HT IBSS when a beacon with HT-info is received after the station
1499 	 * has already been added.
1500 	 */
1501 	if (sta->ht_cap.ht_supported) {
1502 		an->maxampdu = (1 << (IEEE80211_HT_MAX_AMPDU_FACTOR +
1503 				      sta->ht_cap.ampdu_factor)) - 1;
1504 		density = ath9k_parse_mpdudensity(sta->ht_cap.ampdu_density);
1505 		an->mpdudensity = density;
1506 	}
1507 
1508 	/* force sequence number allocation for pending frames */
1509 	ath_tx_tid_change_state(sc, txtid);
1510 
1511 	txtid->active = true;
1512 	*ssn = txtid->seq_start = txtid->seq_next;
1513 	txtid->bar_index = -1;
1514 
1515 	memset(txtid->tx_buf, 0, sizeof(txtid->tx_buf));
1516 	txtid->baw_head = txtid->baw_tail = 0;
1517 
1518 	ath_txq_unlock_complete(sc, txq);
1519 
1520 	return 0;
1521 }
1522 
1523 void ath_tx_aggr_stop(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid)
1524 {
1525 	struct ath_node *an = (struct ath_node *)sta->drv_priv;
1526 	struct ath_atx_tid *txtid = ATH_AN_2_TID(an, tid);
1527 	struct ath_txq *txq = txtid->ac->txq;
1528 
1529 	ath_txq_lock(sc, txq);
1530 	txtid->active = false;
1531 	ath_tx_flush_tid(sc, txtid);
1532 	ath_tx_tid_change_state(sc, txtid);
1533 	ath_txq_unlock_complete(sc, txq);
1534 }
1535 
1536 void ath_tx_aggr_sleep(struct ieee80211_sta *sta, struct ath_softc *sc,
1537 		       struct ath_node *an)
1538 {
1539 	struct ath_atx_tid *tid;
1540 	struct ath_atx_ac *ac;
1541 	struct ath_txq *txq;
1542 	bool buffered;
1543 	int tidno;
1544 
1545 	for (tidno = 0, tid = &an->tid[tidno];
1546 	     tidno < IEEE80211_NUM_TIDS; tidno++, tid++) {
1547 
1548 		ac = tid->ac;
1549 		txq = ac->txq;
1550 
1551 		ath_txq_lock(sc, txq);
1552 
1553 		if (!tid->sched) {
1554 			ath_txq_unlock(sc, txq);
1555 			continue;
1556 		}
1557 
1558 		buffered = ath_tid_has_buffered(tid);
1559 
1560 		tid->sched = false;
1561 		list_del(&tid->list);
1562 
1563 		if (ac->sched) {
1564 			ac->sched = false;
1565 			list_del(&ac->list);
1566 		}
1567 
1568 		ath_txq_unlock(sc, txq);
1569 
1570 		ieee80211_sta_set_buffered(sta, tidno, buffered);
1571 	}
1572 }
1573 
1574 void ath_tx_aggr_wakeup(struct ath_softc *sc, struct ath_node *an)
1575 {
1576 	struct ath_atx_tid *tid;
1577 	struct ath_atx_ac *ac;
1578 	struct ath_txq *txq;
1579 	int tidno;
1580 
1581 	for (tidno = 0, tid = &an->tid[tidno];
1582 	     tidno < IEEE80211_NUM_TIDS; tidno++, tid++) {
1583 
1584 		ac = tid->ac;
1585 		txq = ac->txq;
1586 
1587 		ath_txq_lock(sc, txq);
1588 		ac->clear_ps_filter = true;
1589 
1590 		if (ath_tid_has_buffered(tid)) {
1591 			ath_tx_queue_tid(sc, txq, tid);
1592 			ath_txq_schedule(sc, txq);
1593 		}
1594 
1595 		ath_txq_unlock_complete(sc, txq);
1596 	}
1597 }
1598 
1599 void ath_tx_aggr_resume(struct ath_softc *sc, struct ieee80211_sta *sta,
1600 			u16 tidno)
1601 {
1602 	struct ath_atx_tid *tid;
1603 	struct ath_node *an;
1604 	struct ath_txq *txq;
1605 
1606 	an = (struct ath_node *)sta->drv_priv;
1607 	tid = ATH_AN_2_TID(an, tidno);
1608 	txq = tid->ac->txq;
1609 
1610 	ath_txq_lock(sc, txq);
1611 
1612 	tid->baw_size = IEEE80211_MIN_AMPDU_BUF << sta->ht_cap.ampdu_factor;
1613 
1614 	if (ath_tid_has_buffered(tid)) {
1615 		ath_tx_queue_tid(sc, txq, tid);
1616 		ath_txq_schedule(sc, txq);
1617 	}
1618 
1619 	ath_txq_unlock_complete(sc, txq);
1620 }
1621 
1622 void ath9k_release_buffered_frames(struct ieee80211_hw *hw,
1623 				   struct ieee80211_sta *sta,
1624 				   u16 tids, int nframes,
1625 				   enum ieee80211_frame_release_type reason,
1626 				   bool more_data)
1627 {
1628 	struct ath_softc *sc = hw->priv;
1629 	struct ath_node *an = (struct ath_node *)sta->drv_priv;
1630 	struct ath_txq *txq = sc->tx.uapsdq;
1631 	struct ieee80211_tx_info *info;
1632 	struct list_head bf_q;
1633 	struct ath_buf *bf_tail = NULL, *bf;
1634 	struct sk_buff_head *tid_q;
1635 	int sent = 0;
1636 	int i;
1637 
1638 	INIT_LIST_HEAD(&bf_q);
1639 	for (i = 0; tids && nframes; i++, tids >>= 1) {
1640 		struct ath_atx_tid *tid;
1641 
1642 		if (!(tids & 1))
1643 			continue;
1644 
1645 		tid = ATH_AN_2_TID(an, i);
1646 
1647 		ath_txq_lock(sc, tid->ac->txq);
1648 		while (nframes > 0) {
1649 			bf = ath_tx_get_tid_subframe(sc, sc->tx.uapsdq, tid, &tid_q);
1650 			if (!bf)
1651 				break;
1652 
1653 			__skb_unlink(bf->bf_mpdu, tid_q);
1654 			list_add_tail(&bf->list, &bf_q);
1655 			ath_set_rates(tid->an->vif, tid->an->sta, bf);
1656 			if (bf_isampdu(bf)) {
1657 				ath_tx_addto_baw(sc, tid, bf);
1658 				bf->bf_state.bf_type &= ~BUF_AGGR;
1659 			}
1660 			if (bf_tail)
1661 				bf_tail->bf_next = bf;
1662 
1663 			bf_tail = bf;
1664 			nframes--;
1665 			sent++;
1666 			TX_STAT_INC(txq->axq_qnum, a_queued_hw);
1667 
1668 			if (an->sta && !ath_tid_has_buffered(tid))
1669 				ieee80211_sta_set_buffered(an->sta, i, false);
1670 		}
1671 		ath_txq_unlock_complete(sc, tid->ac->txq);
1672 	}
1673 
1674 	if (list_empty(&bf_q))
1675 		return;
1676 
1677 	info = IEEE80211_SKB_CB(bf_tail->bf_mpdu);
1678 	info->flags |= IEEE80211_TX_STATUS_EOSP;
1679 
1680 	bf = list_first_entry(&bf_q, struct ath_buf, list);
1681 	ath_txq_lock(sc, txq);
1682 	ath_tx_fill_desc(sc, bf, txq, 0);
1683 	ath_tx_txqaddbuf(sc, txq, &bf_q, false);
1684 	ath_txq_unlock(sc, txq);
1685 }
1686 
1687 /********************/
1688 /* Queue Management */
1689 /********************/
1690 
1691 struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype)
1692 {
1693 	struct ath_hw *ah = sc->sc_ah;
1694 	struct ath9k_tx_queue_info qi;
1695 	static const int subtype_txq_to_hwq[] = {
1696 		[IEEE80211_AC_BE] = ATH_TXQ_AC_BE,
1697 		[IEEE80211_AC_BK] = ATH_TXQ_AC_BK,
1698 		[IEEE80211_AC_VI] = ATH_TXQ_AC_VI,
1699 		[IEEE80211_AC_VO] = ATH_TXQ_AC_VO,
1700 	};
1701 	int axq_qnum, i;
1702 
1703 	memset(&qi, 0, sizeof(qi));
1704 	qi.tqi_subtype = subtype_txq_to_hwq[subtype];
1705 	qi.tqi_aifs = ATH9K_TXQ_USEDEFAULT;
1706 	qi.tqi_cwmin = ATH9K_TXQ_USEDEFAULT;
1707 	qi.tqi_cwmax = ATH9K_TXQ_USEDEFAULT;
1708 	qi.tqi_physCompBuf = 0;
1709 
1710 	/*
1711 	 * Enable interrupts only for EOL and DESC conditions.
1712 	 * We mark tx descriptors to receive a DESC interrupt
1713 	 * when a tx queue gets deep; otherwise waiting for the
1714 	 * EOL to reap descriptors.  Note that this is done to
1715 	 * reduce interrupt load and this only defers reaping
1716 	 * descriptors, never transmitting frames.  Aside from
1717 	 * reducing interrupts this also permits more concurrency.
1718 	 * The only potential downside is if the tx queue backs
1719 	 * up in which case the top half of the kernel may backup
1720 	 * due to a lack of tx descriptors.
1721 	 *
1722 	 * The UAPSD queue is an exception, since we take a desc-
1723 	 * based intr on the EOSP frames.
1724 	 */
1725 	if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
1726 		qi.tqi_qflags = TXQ_FLAG_TXINT_ENABLE;
1727 	} else {
1728 		if (qtype == ATH9K_TX_QUEUE_UAPSD)
1729 			qi.tqi_qflags = TXQ_FLAG_TXDESCINT_ENABLE;
1730 		else
1731 			qi.tqi_qflags = TXQ_FLAG_TXEOLINT_ENABLE |
1732 					TXQ_FLAG_TXDESCINT_ENABLE;
1733 	}
1734 	axq_qnum = ath9k_hw_setuptxqueue(ah, qtype, &qi);
1735 	if (axq_qnum == -1) {
1736 		/*
1737 		 * NB: don't print a message, this happens
1738 		 * normally on parts with too few tx queues
1739 		 */
1740 		return NULL;
1741 	}
1742 	if (!ATH_TXQ_SETUP(sc, axq_qnum)) {
1743 		struct ath_txq *txq = &sc->tx.txq[axq_qnum];
1744 
1745 		txq->axq_qnum = axq_qnum;
1746 		txq->mac80211_qnum = -1;
1747 		txq->axq_link = NULL;
1748 		__skb_queue_head_init(&txq->complete_q);
1749 		INIT_LIST_HEAD(&txq->axq_q);
1750 		spin_lock_init(&txq->axq_lock);
1751 		txq->axq_depth = 0;
1752 		txq->axq_ampdu_depth = 0;
1753 		txq->axq_tx_inprogress = false;
1754 		sc->tx.txqsetup |= 1<<axq_qnum;
1755 
1756 		txq->txq_headidx = txq->txq_tailidx = 0;
1757 		for (i = 0; i < ATH_TXFIFO_DEPTH; i++)
1758 			INIT_LIST_HEAD(&txq->txq_fifo[i]);
1759 	}
1760 	return &sc->tx.txq[axq_qnum];
1761 }
1762 
1763 int ath_txq_update(struct ath_softc *sc, int qnum,
1764 		   struct ath9k_tx_queue_info *qinfo)
1765 {
1766 	struct ath_hw *ah = sc->sc_ah;
1767 	int error = 0;
1768 	struct ath9k_tx_queue_info qi;
1769 
1770 	BUG_ON(sc->tx.txq[qnum].axq_qnum != qnum);
1771 
1772 	ath9k_hw_get_txq_props(ah, qnum, &qi);
1773 	qi.tqi_aifs = qinfo->tqi_aifs;
1774 	qi.tqi_cwmin = qinfo->tqi_cwmin;
1775 	qi.tqi_cwmax = qinfo->tqi_cwmax;
1776 	qi.tqi_burstTime = qinfo->tqi_burstTime;
1777 	qi.tqi_readyTime = qinfo->tqi_readyTime;
1778 
1779 	if (!ath9k_hw_set_txq_props(ah, qnum, &qi)) {
1780 		ath_err(ath9k_hw_common(sc->sc_ah),
1781 			"Unable to update hardware queue %u!\n", qnum);
1782 		error = -EIO;
1783 	} else {
1784 		ath9k_hw_resettxqueue(ah, qnum);
1785 	}
1786 
1787 	return error;
1788 }
1789 
1790 int ath_cabq_update(struct ath_softc *sc)
1791 {
1792 	struct ath9k_tx_queue_info qi;
1793 	struct ath_beacon_config *cur_conf = &sc->cur_chan->beacon;
1794 	int qnum = sc->beacon.cabq->axq_qnum;
1795 
1796 	ath9k_hw_get_txq_props(sc->sc_ah, qnum, &qi);
1797 
1798 	qi.tqi_readyTime = (TU_TO_USEC(cur_conf->beacon_interval) *
1799 			    ATH_CABQ_READY_TIME) / 100;
1800 	ath_txq_update(sc, qnum, &qi);
1801 
1802 	return 0;
1803 }
1804 
1805 static void ath_drain_txq_list(struct ath_softc *sc, struct ath_txq *txq,
1806 			       struct list_head *list)
1807 {
1808 	struct ath_buf *bf, *lastbf;
1809 	struct list_head bf_head;
1810 	struct ath_tx_status ts;
1811 
1812 	memset(&ts, 0, sizeof(ts));
1813 	ts.ts_status = ATH9K_TX_FLUSH;
1814 	INIT_LIST_HEAD(&bf_head);
1815 
1816 	while (!list_empty(list)) {
1817 		bf = list_first_entry(list, struct ath_buf, list);
1818 
1819 		if (bf->bf_state.stale) {
1820 			list_del(&bf->list);
1821 
1822 			ath_tx_return_buffer(sc, bf);
1823 			continue;
1824 		}
1825 
1826 		lastbf = bf->bf_lastbf;
1827 		list_cut_position(&bf_head, list, &lastbf->list);
1828 		ath_tx_process_buffer(sc, txq, &ts, bf, &bf_head);
1829 	}
1830 }
1831 
1832 /*
1833  * Drain a given TX queue (could be Beacon or Data)
1834  *
1835  * This assumes output has been stopped and
1836  * we do not need to block ath_tx_tasklet.
1837  */
1838 void ath_draintxq(struct ath_softc *sc, struct ath_txq *txq)
1839 {
1840 	ath_txq_lock(sc, txq);
1841 
1842 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
1843 		int idx = txq->txq_tailidx;
1844 
1845 		while (!list_empty(&txq->txq_fifo[idx])) {
1846 			ath_drain_txq_list(sc, txq, &txq->txq_fifo[idx]);
1847 
1848 			INCR(idx, ATH_TXFIFO_DEPTH);
1849 		}
1850 		txq->txq_tailidx = idx;
1851 	}
1852 
1853 	txq->axq_link = NULL;
1854 	txq->axq_tx_inprogress = false;
1855 	ath_drain_txq_list(sc, txq, &txq->axq_q);
1856 
1857 	ath_txq_unlock_complete(sc, txq);
1858 }
1859 
1860 bool ath_drain_all_txq(struct ath_softc *sc)
1861 {
1862 	struct ath_hw *ah = sc->sc_ah;
1863 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1864 	struct ath_txq *txq;
1865 	int i;
1866 	u32 npend = 0;
1867 
1868 	if (test_bit(ATH_OP_INVALID, &common->op_flags))
1869 		return true;
1870 
1871 	ath9k_hw_abort_tx_dma(ah);
1872 
1873 	/* Check if any queue remains active */
1874 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
1875 		if (!ATH_TXQ_SETUP(sc, i))
1876 			continue;
1877 
1878 		if (!sc->tx.txq[i].axq_depth)
1879 			continue;
1880 
1881 		if (ath9k_hw_numtxpending(ah, sc->tx.txq[i].axq_qnum))
1882 			npend |= BIT(i);
1883 	}
1884 
1885 	if (npend)
1886 		ath_err(common, "Failed to stop TX DMA, queues=0x%03x!\n", npend);
1887 
1888 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
1889 		if (!ATH_TXQ_SETUP(sc, i))
1890 			continue;
1891 
1892 		/*
1893 		 * The caller will resume queues with ieee80211_wake_queues.
1894 		 * Mark the queue as not stopped to prevent ath_tx_complete
1895 		 * from waking the queue too early.
1896 		 */
1897 		txq = &sc->tx.txq[i];
1898 		txq->stopped = false;
1899 		ath_draintxq(sc, txq);
1900 	}
1901 
1902 	return !npend;
1903 }
1904 
1905 void ath_tx_cleanupq(struct ath_softc *sc, struct ath_txq *txq)
1906 {
1907 	ath9k_hw_releasetxqueue(sc->sc_ah, txq->axq_qnum);
1908 	sc->tx.txqsetup &= ~(1<<txq->axq_qnum);
1909 }
1910 
1911 /* For each acq entry, for each tid, try to schedule packets
1912  * for transmit until ampdu_depth has reached min Q depth.
1913  */
1914 void ath_txq_schedule(struct ath_softc *sc, struct ath_txq *txq)
1915 {
1916 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1917 	struct ath_atx_ac *ac, *last_ac;
1918 	struct ath_atx_tid *tid, *last_tid;
1919 	struct list_head *ac_list;
1920 	bool sent = false;
1921 
1922 	if (txq->mac80211_qnum < 0)
1923 		return;
1924 
1925 	if (test_bit(ATH_OP_HW_RESET, &common->op_flags))
1926 		return;
1927 
1928 	spin_lock_bh(&sc->chan_lock);
1929 	ac_list = &sc->cur_chan->acq[txq->mac80211_qnum];
1930 
1931 	if (list_empty(ac_list)) {
1932 		spin_unlock_bh(&sc->chan_lock);
1933 		return;
1934 	}
1935 
1936 	rcu_read_lock();
1937 
1938 	last_ac = list_entry(ac_list->prev, struct ath_atx_ac, list);
1939 	while (!list_empty(ac_list)) {
1940 		bool stop = false;
1941 
1942 		if (sc->cur_chan->stopped)
1943 			break;
1944 
1945 		ac = list_first_entry(ac_list, struct ath_atx_ac, list);
1946 		last_tid = list_entry(ac->tid_q.prev, struct ath_atx_tid, list);
1947 		list_del(&ac->list);
1948 		ac->sched = false;
1949 
1950 		while (!list_empty(&ac->tid_q)) {
1951 
1952 			tid = list_first_entry(&ac->tid_q, struct ath_atx_tid,
1953 					       list);
1954 			list_del(&tid->list);
1955 			tid->sched = false;
1956 
1957 			if (ath_tx_sched_aggr(sc, txq, tid, &stop))
1958 				sent = true;
1959 
1960 			/*
1961 			 * add tid to round-robin queue if more frames
1962 			 * are pending for the tid
1963 			 */
1964 			if (ath_tid_has_buffered(tid))
1965 				ath_tx_queue_tid(sc, txq, tid);
1966 
1967 			if (stop || tid == last_tid)
1968 				break;
1969 		}
1970 
1971 		if (!list_empty(&ac->tid_q) && !ac->sched) {
1972 			ac->sched = true;
1973 			list_add_tail(&ac->list, ac_list);
1974 		}
1975 
1976 		if (stop)
1977 			break;
1978 
1979 		if (ac == last_ac) {
1980 			if (!sent)
1981 				break;
1982 
1983 			sent = false;
1984 			last_ac = list_entry(ac_list->prev,
1985 					     struct ath_atx_ac, list);
1986 		}
1987 	}
1988 
1989 	rcu_read_unlock();
1990 	spin_unlock_bh(&sc->chan_lock);
1991 }
1992 
1993 void ath_txq_schedule_all(struct ath_softc *sc)
1994 {
1995 	struct ath_txq *txq;
1996 	int i;
1997 
1998 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
1999 		txq = sc->tx.txq_map[i];
2000 
2001 		spin_lock_bh(&txq->axq_lock);
2002 		ath_txq_schedule(sc, txq);
2003 		spin_unlock_bh(&txq->axq_lock);
2004 	}
2005 }
2006 
2007 /***********/
2008 /* TX, DMA */
2009 /***********/
2010 
2011 /*
2012  * Insert a chain of ath_buf (descriptors) on a txq and
2013  * assume the descriptors are already chained together by caller.
2014  */
2015 static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq,
2016 			     struct list_head *head, bool internal)
2017 {
2018 	struct ath_hw *ah = sc->sc_ah;
2019 	struct ath_common *common = ath9k_hw_common(ah);
2020 	struct ath_buf *bf, *bf_last;
2021 	bool puttxbuf = false;
2022 	bool edma;
2023 
2024 	/*
2025 	 * Insert the frame on the outbound list and
2026 	 * pass it on to the hardware.
2027 	 */
2028 
2029 	if (list_empty(head))
2030 		return;
2031 
2032 	edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
2033 	bf = list_first_entry(head, struct ath_buf, list);
2034 	bf_last = list_entry(head->prev, struct ath_buf, list);
2035 
2036 	ath_dbg(common, QUEUE, "qnum: %d, txq depth: %d\n",
2037 		txq->axq_qnum, txq->axq_depth);
2038 
2039 	if (edma && list_empty(&txq->txq_fifo[txq->txq_headidx])) {
2040 		list_splice_tail_init(head, &txq->txq_fifo[txq->txq_headidx]);
2041 		INCR(txq->txq_headidx, ATH_TXFIFO_DEPTH);
2042 		puttxbuf = true;
2043 	} else {
2044 		list_splice_tail_init(head, &txq->axq_q);
2045 
2046 		if (txq->axq_link) {
2047 			ath9k_hw_set_desc_link(ah, txq->axq_link, bf->bf_daddr);
2048 			ath_dbg(common, XMIT, "link[%u] (%p)=%llx (%p)\n",
2049 				txq->axq_qnum, txq->axq_link,
2050 				ito64(bf->bf_daddr), bf->bf_desc);
2051 		} else if (!edma)
2052 			puttxbuf = true;
2053 
2054 		txq->axq_link = bf_last->bf_desc;
2055 	}
2056 
2057 	if (puttxbuf) {
2058 		TX_STAT_INC(txq->axq_qnum, puttxbuf);
2059 		ath9k_hw_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
2060 		ath_dbg(common, XMIT, "TXDP[%u] = %llx (%p)\n",
2061 			txq->axq_qnum, ito64(bf->bf_daddr), bf->bf_desc);
2062 	}
2063 
2064 	if (!edma || sc->tx99_state) {
2065 		TX_STAT_INC(txq->axq_qnum, txstart);
2066 		ath9k_hw_txstart(ah, txq->axq_qnum);
2067 	}
2068 
2069 	if (!internal) {
2070 		while (bf) {
2071 			txq->axq_depth++;
2072 			if (bf_is_ampdu_not_probing(bf))
2073 				txq->axq_ampdu_depth++;
2074 
2075 			bf_last = bf->bf_lastbf;
2076 			bf = bf_last->bf_next;
2077 			bf_last->bf_next = NULL;
2078 		}
2079 	}
2080 }
2081 
2082 static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
2083 			       struct ath_atx_tid *tid, struct sk_buff *skb)
2084 {
2085 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
2086 	struct ath_frame_info *fi = get_frame_info(skb);
2087 	struct list_head bf_head;
2088 	struct ath_buf *bf = fi->bf;
2089 
2090 	INIT_LIST_HEAD(&bf_head);
2091 	list_add_tail(&bf->list, &bf_head);
2092 	bf->bf_state.bf_type = 0;
2093 	if (tid && (tx_info->flags & IEEE80211_TX_CTL_AMPDU)) {
2094 		bf->bf_state.bf_type = BUF_AMPDU;
2095 		ath_tx_addto_baw(sc, tid, bf);
2096 	}
2097 
2098 	bf->bf_next = NULL;
2099 	bf->bf_lastbf = bf;
2100 	ath_tx_fill_desc(sc, bf, txq, fi->framelen);
2101 	ath_tx_txqaddbuf(sc, txq, &bf_head, false);
2102 	TX_STAT_INC(txq->axq_qnum, queued);
2103 }
2104 
2105 static void setup_frame_info(struct ieee80211_hw *hw,
2106 			     struct ieee80211_sta *sta,
2107 			     struct sk_buff *skb,
2108 			     int framelen)
2109 {
2110 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
2111 	struct ieee80211_key_conf *hw_key = tx_info->control.hw_key;
2112 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2113 	const struct ieee80211_rate *rate;
2114 	struct ath_frame_info *fi = get_frame_info(skb);
2115 	struct ath_node *an = NULL;
2116 	enum ath9k_key_type keytype;
2117 	bool short_preamble = false;
2118 
2119 	/*
2120 	 * We check if Short Preamble is needed for the CTS rate by
2121 	 * checking the BSS's global flag.
2122 	 * But for the rate series, IEEE80211_TX_RC_USE_SHORT_PREAMBLE is used.
2123 	 */
2124 	if (tx_info->control.vif &&
2125 	    tx_info->control.vif->bss_conf.use_short_preamble)
2126 		short_preamble = true;
2127 
2128 	rate = ieee80211_get_rts_cts_rate(hw, tx_info);
2129 	keytype = ath9k_cmn_get_hw_crypto_keytype(skb);
2130 
2131 	if (sta)
2132 		an = (struct ath_node *) sta->drv_priv;
2133 
2134 	memset(fi, 0, sizeof(*fi));
2135 	fi->txq = -1;
2136 	if (hw_key)
2137 		fi->keyix = hw_key->hw_key_idx;
2138 	else if (an && ieee80211_is_data(hdr->frame_control) && an->ps_key > 0)
2139 		fi->keyix = an->ps_key;
2140 	else
2141 		fi->keyix = ATH9K_TXKEYIX_INVALID;
2142 	fi->keytype = keytype;
2143 	fi->framelen = framelen;
2144 	fi->tx_power = MAX_RATE_POWER;
2145 
2146 	if (!rate)
2147 		return;
2148 	fi->rtscts_rate = rate->hw_value;
2149 	if (short_preamble)
2150 		fi->rtscts_rate |= rate->hw_value_short;
2151 }
2152 
2153 u8 ath_txchainmask_reduction(struct ath_softc *sc, u8 chainmask, u32 rate)
2154 {
2155 	struct ath_hw *ah = sc->sc_ah;
2156 	struct ath9k_channel *curchan = ah->curchan;
2157 
2158 	if ((ah->caps.hw_caps & ATH9K_HW_CAP_APM) && IS_CHAN_5GHZ(curchan) &&
2159 	    (chainmask == 0x7) && (rate < 0x90))
2160 		return 0x3;
2161 	else if (AR_SREV_9462(ah) && ath9k_hw_btcoex_is_enabled(ah) &&
2162 		 IS_CCK_RATE(rate))
2163 		return 0x2;
2164 	else
2165 		return chainmask;
2166 }
2167 
2168 /*
2169  * Assign a descriptor (and sequence number if necessary,
2170  * and map buffer for DMA. Frees skb on error
2171  */
2172 static struct ath_buf *ath_tx_setup_buffer(struct ath_softc *sc,
2173 					   struct ath_txq *txq,
2174 					   struct ath_atx_tid *tid,
2175 					   struct sk_buff *skb)
2176 {
2177 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2178 	struct ath_frame_info *fi = get_frame_info(skb);
2179 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2180 	struct ath_buf *bf;
2181 	int fragno;
2182 	u16 seqno;
2183 
2184 	bf = ath_tx_get_buffer(sc);
2185 	if (!bf) {
2186 		ath_dbg(common, XMIT, "TX buffers are full\n");
2187 		return NULL;
2188 	}
2189 
2190 	ATH_TXBUF_RESET(bf);
2191 
2192 	if (tid && ieee80211_is_data_present(hdr->frame_control)) {
2193 		fragno = le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG;
2194 		seqno = tid->seq_next;
2195 		hdr->seq_ctrl = cpu_to_le16(tid->seq_next << IEEE80211_SEQ_SEQ_SHIFT);
2196 
2197 		if (fragno)
2198 			hdr->seq_ctrl |= cpu_to_le16(fragno);
2199 
2200 		if (!ieee80211_has_morefrags(hdr->frame_control))
2201 			INCR(tid->seq_next, IEEE80211_SEQ_MAX);
2202 
2203 		bf->bf_state.seqno = seqno;
2204 	}
2205 
2206 	bf->bf_mpdu = skb;
2207 
2208 	bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
2209 					 skb->len, DMA_TO_DEVICE);
2210 	if (unlikely(dma_mapping_error(sc->dev, bf->bf_buf_addr))) {
2211 		bf->bf_mpdu = NULL;
2212 		bf->bf_buf_addr = 0;
2213 		ath_err(ath9k_hw_common(sc->sc_ah),
2214 			"dma_mapping_error() on TX\n");
2215 		ath_tx_return_buffer(sc, bf);
2216 		return NULL;
2217 	}
2218 
2219 	fi->bf = bf;
2220 
2221 	return bf;
2222 }
2223 
2224 void ath_assign_seq(struct ath_common *common, struct sk_buff *skb)
2225 {
2226 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2227 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2228 	struct ieee80211_vif *vif = info->control.vif;
2229 	struct ath_vif *avp;
2230 
2231 	if (!(info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ))
2232 		return;
2233 
2234 	if (!vif)
2235 		return;
2236 
2237 	avp = (struct ath_vif *)vif->drv_priv;
2238 
2239 	if (info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)
2240 		avp->seq_no += 0x10;
2241 
2242 	hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
2243 	hdr->seq_ctrl |= cpu_to_le16(avp->seq_no);
2244 }
2245 
2246 static int ath_tx_prepare(struct ieee80211_hw *hw, struct sk_buff *skb,
2247 			  struct ath_tx_control *txctl)
2248 {
2249 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2250 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2251 	struct ieee80211_sta *sta = txctl->sta;
2252 	struct ieee80211_vif *vif = info->control.vif;
2253 	struct ath_vif *avp;
2254 	struct ath_softc *sc = hw->priv;
2255 	int frmlen = skb->len + FCS_LEN;
2256 	int padpos, padsize;
2257 
2258 	/* NOTE:  sta can be NULL according to net/mac80211.h */
2259 	if (sta)
2260 		txctl->an = (struct ath_node *)sta->drv_priv;
2261 	else if (vif && ieee80211_is_data(hdr->frame_control)) {
2262 		avp = (void *)vif->drv_priv;
2263 		txctl->an = &avp->mcast_node;
2264 	}
2265 
2266 	if (info->control.hw_key)
2267 		frmlen += info->control.hw_key->icv_len;
2268 
2269 	ath_assign_seq(ath9k_hw_common(sc->sc_ah), skb);
2270 
2271 	if ((vif && vif->type != NL80211_IFTYPE_AP &&
2272 	            vif->type != NL80211_IFTYPE_AP_VLAN) ||
2273 	    !ieee80211_is_data(hdr->frame_control))
2274 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
2275 
2276 	/* Add the padding after the header if this is not already done */
2277 	padpos = ieee80211_hdrlen(hdr->frame_control);
2278 	padsize = padpos & 3;
2279 	if (padsize && skb->len > padpos) {
2280 		if (skb_headroom(skb) < padsize)
2281 			return -ENOMEM;
2282 
2283 		skb_push(skb, padsize);
2284 		memmove(skb->data, skb->data + padsize, padpos);
2285 	}
2286 
2287 	setup_frame_info(hw, sta, skb, frmlen);
2288 	return 0;
2289 }
2290 
2291 
2292 /* Upon failure caller should free skb */
2293 int ath_tx_start(struct ieee80211_hw *hw, struct sk_buff *skb,
2294 		 struct ath_tx_control *txctl)
2295 {
2296 	struct ieee80211_hdr *hdr;
2297 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2298 	struct ieee80211_sta *sta = txctl->sta;
2299 	struct ieee80211_vif *vif = info->control.vif;
2300 	struct ath_frame_info *fi = get_frame_info(skb);
2301 	struct ath_vif *avp = NULL;
2302 	struct ath_softc *sc = hw->priv;
2303 	struct ath_txq *txq = txctl->txq;
2304 	struct ath_atx_tid *tid = NULL;
2305 	struct ath_buf *bf;
2306 	bool queue, skip_uapsd = false, ps_resp;
2307 	int q, ret;
2308 
2309 	if (vif)
2310 		avp = (void *)vif->drv_priv;
2311 
2312 	if (info->flags & IEEE80211_TX_CTL_TX_OFFCHAN)
2313 		txctl->force_channel = true;
2314 
2315 	ps_resp = !!(info->control.flags & IEEE80211_TX_CTRL_PS_RESPONSE);
2316 
2317 	ret = ath_tx_prepare(hw, skb, txctl);
2318 	if (ret)
2319 	    return ret;
2320 
2321 	hdr = (struct ieee80211_hdr *) skb->data;
2322 	/*
2323 	 * At this point, the vif, hw_key and sta pointers in the tx control
2324 	 * info are no longer valid (overwritten by the ath_frame_info data.
2325 	 */
2326 
2327 	q = skb_get_queue_mapping(skb);
2328 
2329 	ath_txq_lock(sc, txq);
2330 	if (txq == sc->tx.txq_map[q]) {
2331 		fi->txq = q;
2332 		if (++txq->pending_frames > sc->tx.txq_max_pending[q] &&
2333 		    !txq->stopped) {
2334 			if (ath9k_is_chanctx_enabled())
2335 				ieee80211_stop_queue(sc->hw, info->hw_queue);
2336 			else
2337 				ieee80211_stop_queue(sc->hw, q);
2338 			txq->stopped = true;
2339 		}
2340 	}
2341 
2342 	queue = ieee80211_is_data_present(hdr->frame_control);
2343 
2344 	/* Force queueing of all frames that belong to a virtual interface on
2345 	 * a different channel context, to ensure that they are sent on the
2346 	 * correct channel.
2347 	 */
2348 	if (((avp && avp->chanctx != sc->cur_chan) ||
2349 	     sc->cur_chan->stopped) && !txctl->force_channel) {
2350 		if (!txctl->an)
2351 			txctl->an = &avp->mcast_node;
2352 		queue = true;
2353 		skip_uapsd = true;
2354 	}
2355 
2356 	if (txctl->an && queue)
2357 		tid = ath_get_skb_tid(sc, txctl->an, skb);
2358 
2359 	if (!skip_uapsd && ps_resp) {
2360 		ath_txq_unlock(sc, txq);
2361 		txq = sc->tx.uapsdq;
2362 		ath_txq_lock(sc, txq);
2363 	} else if (txctl->an && queue) {
2364 		WARN_ON(tid->ac->txq != txctl->txq);
2365 
2366 		if (info->flags & IEEE80211_TX_CTL_CLEAR_PS_FILT)
2367 			tid->ac->clear_ps_filter = true;
2368 
2369 		/*
2370 		 * Add this frame to software queue for scheduling later
2371 		 * for aggregation.
2372 		 */
2373 		TX_STAT_INC(txq->axq_qnum, a_queued_sw);
2374 		__skb_queue_tail(&tid->buf_q, skb);
2375 		if (!txctl->an->sleeping)
2376 			ath_tx_queue_tid(sc, txq, tid);
2377 
2378 		ath_txq_schedule(sc, txq);
2379 		goto out;
2380 	}
2381 
2382 	bf = ath_tx_setup_buffer(sc, txq, tid, skb);
2383 	if (!bf) {
2384 		ath_txq_skb_done(sc, txq, skb);
2385 		if (txctl->paprd)
2386 			dev_kfree_skb_any(skb);
2387 		else
2388 			ieee80211_free_txskb(sc->hw, skb);
2389 		goto out;
2390 	}
2391 
2392 	bf->bf_state.bfs_paprd = txctl->paprd;
2393 
2394 	if (txctl->paprd)
2395 		bf->bf_state.bfs_paprd_timestamp = jiffies;
2396 
2397 	ath_set_rates(vif, sta, bf);
2398 	ath_tx_send_normal(sc, txq, tid, skb);
2399 
2400 out:
2401 	ath_txq_unlock(sc, txq);
2402 
2403 	return 0;
2404 }
2405 
2406 void ath_tx_cabq(struct ieee80211_hw *hw, struct ieee80211_vif *vif,
2407 		 struct sk_buff *skb)
2408 {
2409 	struct ath_softc *sc = hw->priv;
2410 	struct ath_tx_control txctl = {
2411 		.txq = sc->beacon.cabq
2412 	};
2413 	struct ath_tx_info info = {};
2414 	struct ieee80211_hdr *hdr;
2415 	struct ath_buf *bf_tail = NULL;
2416 	struct ath_buf *bf;
2417 	LIST_HEAD(bf_q);
2418 	int duration = 0;
2419 	int max_duration;
2420 
2421 	max_duration =
2422 		sc->cur_chan->beacon.beacon_interval * 1000 *
2423 		sc->cur_chan->beacon.dtim_period / ATH_BCBUF;
2424 
2425 	do {
2426 		struct ath_frame_info *fi = get_frame_info(skb);
2427 
2428 		if (ath_tx_prepare(hw, skb, &txctl))
2429 			break;
2430 
2431 		bf = ath_tx_setup_buffer(sc, txctl.txq, NULL, skb);
2432 		if (!bf)
2433 			break;
2434 
2435 		bf->bf_lastbf = bf;
2436 		ath_set_rates(vif, NULL, bf);
2437 		ath_buf_set_rate(sc, bf, &info, fi->framelen, false);
2438 		duration += info.rates[0].PktDuration;
2439 		if (bf_tail)
2440 			bf_tail->bf_next = bf;
2441 
2442 		list_add_tail(&bf->list, &bf_q);
2443 		bf_tail = bf;
2444 		skb = NULL;
2445 
2446 		if (duration > max_duration)
2447 			break;
2448 
2449 		skb = ieee80211_get_buffered_bc(hw, vif);
2450 	} while(skb);
2451 
2452 	if (skb)
2453 		ieee80211_free_txskb(hw, skb);
2454 
2455 	if (list_empty(&bf_q))
2456 		return;
2457 
2458 	bf = list_first_entry(&bf_q, struct ath_buf, list);
2459 	hdr = (struct ieee80211_hdr *) bf->bf_mpdu->data;
2460 
2461 	if (hdr->frame_control & IEEE80211_FCTL_MOREDATA) {
2462 		hdr->frame_control &= ~IEEE80211_FCTL_MOREDATA;
2463 		dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
2464 			sizeof(*hdr), DMA_TO_DEVICE);
2465 	}
2466 
2467 	ath_txq_lock(sc, txctl.txq);
2468 	ath_tx_fill_desc(sc, bf, txctl.txq, 0);
2469 	ath_tx_txqaddbuf(sc, txctl.txq, &bf_q, false);
2470 	TX_STAT_INC(txctl.txq->axq_qnum, queued);
2471 	ath_txq_unlock(sc, txctl.txq);
2472 }
2473 
2474 /*****************/
2475 /* TX Completion */
2476 /*****************/
2477 
2478 static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
2479 			    int tx_flags, struct ath_txq *txq)
2480 {
2481 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
2482 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2483 	struct ieee80211_hdr * hdr = (struct ieee80211_hdr *)skb->data;
2484 	int padpos, padsize;
2485 	unsigned long flags;
2486 
2487 	ath_dbg(common, XMIT, "TX complete: skb: %p\n", skb);
2488 
2489 	if (sc->sc_ah->caldata)
2490 		set_bit(PAPRD_PACKET_SENT, &sc->sc_ah->caldata->cal_flags);
2491 
2492 	if (!(tx_flags & ATH_TX_ERROR)) {
2493 		if (tx_info->flags & IEEE80211_TX_CTL_NO_ACK)
2494 			tx_info->flags |= IEEE80211_TX_STAT_NOACK_TRANSMITTED;
2495 		else
2496 			tx_info->flags |= IEEE80211_TX_STAT_ACK;
2497 	}
2498 
2499 	padpos = ieee80211_hdrlen(hdr->frame_control);
2500 	padsize = padpos & 3;
2501 	if (padsize && skb->len>padpos+padsize) {
2502 		/*
2503 		 * Remove MAC header padding before giving the frame back to
2504 		 * mac80211.
2505 		 */
2506 		memmove(skb->data + padsize, skb->data, padpos);
2507 		skb_pull(skb, padsize);
2508 	}
2509 
2510 	spin_lock_irqsave(&sc->sc_pm_lock, flags);
2511 	if ((sc->ps_flags & PS_WAIT_FOR_TX_ACK) && !txq->axq_depth) {
2512 		sc->ps_flags &= ~PS_WAIT_FOR_TX_ACK;
2513 		ath_dbg(common, PS,
2514 			"Going back to sleep after having received TX status (0x%lx)\n",
2515 			sc->ps_flags & (PS_WAIT_FOR_BEACON |
2516 					PS_WAIT_FOR_CAB |
2517 					PS_WAIT_FOR_PSPOLL_DATA |
2518 					PS_WAIT_FOR_TX_ACK));
2519 	}
2520 	spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
2521 
2522 	__skb_queue_tail(&txq->complete_q, skb);
2523 	ath_txq_skb_done(sc, txq, skb);
2524 }
2525 
2526 static void ath_tx_complete_buf(struct ath_softc *sc, struct ath_buf *bf,
2527 				struct ath_txq *txq, struct list_head *bf_q,
2528 				struct ath_tx_status *ts, int txok)
2529 {
2530 	struct sk_buff *skb = bf->bf_mpdu;
2531 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
2532 	unsigned long flags;
2533 	int tx_flags = 0;
2534 
2535 	if (!txok)
2536 		tx_flags |= ATH_TX_ERROR;
2537 
2538 	if (ts->ts_status & ATH9K_TXERR_FILT)
2539 		tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
2540 
2541 	dma_unmap_single(sc->dev, bf->bf_buf_addr, skb->len, DMA_TO_DEVICE);
2542 	bf->bf_buf_addr = 0;
2543 	if (sc->tx99_state)
2544 		goto skip_tx_complete;
2545 
2546 	if (bf->bf_state.bfs_paprd) {
2547 		if (time_after(jiffies,
2548 				bf->bf_state.bfs_paprd_timestamp +
2549 				msecs_to_jiffies(ATH_PAPRD_TIMEOUT)))
2550 			dev_kfree_skb_any(skb);
2551 		else
2552 			complete(&sc->paprd_complete);
2553 	} else {
2554 		ath_debug_stat_tx(sc, bf, ts, txq, tx_flags);
2555 		ath_tx_complete(sc, skb, tx_flags, txq);
2556 	}
2557 skip_tx_complete:
2558 	/* At this point, skb (bf->bf_mpdu) is consumed...make sure we don't
2559 	 * accidentally reference it later.
2560 	 */
2561 	bf->bf_mpdu = NULL;
2562 
2563 	/*
2564 	 * Return the list of ath_buf of this mpdu to free queue
2565 	 */
2566 	spin_lock_irqsave(&sc->tx.txbuflock, flags);
2567 	list_splice_tail_init(bf_q, &sc->tx.txbuf);
2568 	spin_unlock_irqrestore(&sc->tx.txbuflock, flags);
2569 }
2570 
2571 static void ath_tx_rc_status(struct ath_softc *sc, struct ath_buf *bf,
2572 			     struct ath_tx_status *ts, int nframes, int nbad,
2573 			     int txok)
2574 {
2575 	struct sk_buff *skb = bf->bf_mpdu;
2576 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2577 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
2578 	struct ieee80211_hw *hw = sc->hw;
2579 	struct ath_hw *ah = sc->sc_ah;
2580 	u8 i, tx_rateindex;
2581 
2582 	if (txok)
2583 		tx_info->status.ack_signal = ts->ts_rssi;
2584 
2585 	tx_rateindex = ts->ts_rateindex;
2586 	WARN_ON(tx_rateindex >= hw->max_rates);
2587 
2588 	if (tx_info->flags & IEEE80211_TX_CTL_AMPDU) {
2589 		tx_info->flags |= IEEE80211_TX_STAT_AMPDU;
2590 
2591 		BUG_ON(nbad > nframes);
2592 	}
2593 	tx_info->status.ampdu_len = nframes;
2594 	tx_info->status.ampdu_ack_len = nframes - nbad;
2595 
2596 	if ((ts->ts_status & ATH9K_TXERR_FILT) == 0 &&
2597 	    (tx_info->flags & IEEE80211_TX_CTL_NO_ACK) == 0) {
2598 		/*
2599 		 * If an underrun error is seen assume it as an excessive
2600 		 * retry only if max frame trigger level has been reached
2601 		 * (2 KB for single stream, and 4 KB for dual stream).
2602 		 * Adjust the long retry as if the frame was tried
2603 		 * hw->max_rate_tries times to affect how rate control updates
2604 		 * PER for the failed rate.
2605 		 * In case of congestion on the bus penalizing this type of
2606 		 * underruns should help hardware actually transmit new frames
2607 		 * successfully by eventually preferring slower rates.
2608 		 * This itself should also alleviate congestion on the bus.
2609 		 */
2610 		if (unlikely(ts->ts_flags & (ATH9K_TX_DATA_UNDERRUN |
2611 		                             ATH9K_TX_DELIM_UNDERRUN)) &&
2612 		    ieee80211_is_data(hdr->frame_control) &&
2613 		    ah->tx_trig_level >= sc->sc_ah->config.max_txtrig_level)
2614 			tx_info->status.rates[tx_rateindex].count =
2615 				hw->max_rate_tries;
2616 	}
2617 
2618 	for (i = tx_rateindex + 1; i < hw->max_rates; i++) {
2619 		tx_info->status.rates[i].count = 0;
2620 		tx_info->status.rates[i].idx = -1;
2621 	}
2622 
2623 	tx_info->status.rates[tx_rateindex].count = ts->ts_longretry + 1;
2624 }
2625 
2626 static void ath_tx_processq(struct ath_softc *sc, struct ath_txq *txq)
2627 {
2628 	struct ath_hw *ah = sc->sc_ah;
2629 	struct ath_common *common = ath9k_hw_common(ah);
2630 	struct ath_buf *bf, *lastbf, *bf_held = NULL;
2631 	struct list_head bf_head;
2632 	struct ath_desc *ds;
2633 	struct ath_tx_status ts;
2634 	int status;
2635 
2636 	ath_dbg(common, QUEUE, "tx queue %d (%x), link %p\n",
2637 		txq->axq_qnum, ath9k_hw_gettxbuf(sc->sc_ah, txq->axq_qnum),
2638 		txq->axq_link);
2639 
2640 	ath_txq_lock(sc, txq);
2641 	for (;;) {
2642 		if (test_bit(ATH_OP_HW_RESET, &common->op_flags))
2643 			break;
2644 
2645 		if (list_empty(&txq->axq_q)) {
2646 			txq->axq_link = NULL;
2647 			ath_txq_schedule(sc, txq);
2648 			break;
2649 		}
2650 		bf = list_first_entry(&txq->axq_q, struct ath_buf, list);
2651 
2652 		/*
2653 		 * There is a race condition that a BH gets scheduled
2654 		 * after sw writes TxE and before hw re-load the last
2655 		 * descriptor to get the newly chained one.
2656 		 * Software must keep the last DONE descriptor as a
2657 		 * holding descriptor - software does so by marking
2658 		 * it with the STALE flag.
2659 		 */
2660 		bf_held = NULL;
2661 		if (bf->bf_state.stale) {
2662 			bf_held = bf;
2663 			if (list_is_last(&bf_held->list, &txq->axq_q))
2664 				break;
2665 
2666 			bf = list_entry(bf_held->list.next, struct ath_buf,
2667 					list);
2668 		}
2669 
2670 		lastbf = bf->bf_lastbf;
2671 		ds = lastbf->bf_desc;
2672 
2673 		memset(&ts, 0, sizeof(ts));
2674 		status = ath9k_hw_txprocdesc(ah, ds, &ts);
2675 		if (status == -EINPROGRESS)
2676 			break;
2677 
2678 		TX_STAT_INC(txq->axq_qnum, txprocdesc);
2679 
2680 		/*
2681 		 * Remove ath_buf's of the same transmit unit from txq,
2682 		 * however leave the last descriptor back as the holding
2683 		 * descriptor for hw.
2684 		 */
2685 		lastbf->bf_state.stale = true;
2686 		INIT_LIST_HEAD(&bf_head);
2687 		if (!list_is_singular(&lastbf->list))
2688 			list_cut_position(&bf_head,
2689 				&txq->axq_q, lastbf->list.prev);
2690 
2691 		if (bf_held) {
2692 			list_del(&bf_held->list);
2693 			ath_tx_return_buffer(sc, bf_held);
2694 		}
2695 
2696 		ath_tx_process_buffer(sc, txq, &ts, bf, &bf_head);
2697 	}
2698 	ath_txq_unlock_complete(sc, txq);
2699 }
2700 
2701 void ath_tx_tasklet(struct ath_softc *sc)
2702 {
2703 	struct ath_hw *ah = sc->sc_ah;
2704 	u32 qcumask = ((1 << ATH9K_NUM_TX_QUEUES) - 1) & ah->intr_txqs;
2705 	int i;
2706 
2707 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
2708 		if (ATH_TXQ_SETUP(sc, i) && (qcumask & (1 << i)))
2709 			ath_tx_processq(sc, &sc->tx.txq[i]);
2710 	}
2711 }
2712 
2713 void ath_tx_edma_tasklet(struct ath_softc *sc)
2714 {
2715 	struct ath_tx_status ts;
2716 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2717 	struct ath_hw *ah = sc->sc_ah;
2718 	struct ath_txq *txq;
2719 	struct ath_buf *bf, *lastbf;
2720 	struct list_head bf_head;
2721 	struct list_head *fifo_list;
2722 	int status;
2723 
2724 	for (;;) {
2725 		if (test_bit(ATH_OP_HW_RESET, &common->op_flags))
2726 			break;
2727 
2728 		status = ath9k_hw_txprocdesc(ah, NULL, (void *)&ts);
2729 		if (status == -EINPROGRESS)
2730 			break;
2731 		if (status == -EIO) {
2732 			ath_dbg(common, XMIT, "Error processing tx status\n");
2733 			break;
2734 		}
2735 
2736 		/* Process beacon completions separately */
2737 		if (ts.qid == sc->beacon.beaconq) {
2738 			sc->beacon.tx_processed = true;
2739 			sc->beacon.tx_last = !(ts.ts_status & ATH9K_TXERR_MASK);
2740 
2741 			if (ath9k_is_chanctx_enabled()) {
2742 				ath_chanctx_event(sc, NULL,
2743 						  ATH_CHANCTX_EVENT_BEACON_SENT);
2744 			}
2745 
2746 			ath9k_csa_update(sc);
2747 			continue;
2748 		}
2749 
2750 		txq = &sc->tx.txq[ts.qid];
2751 
2752 		ath_txq_lock(sc, txq);
2753 
2754 		TX_STAT_INC(txq->axq_qnum, txprocdesc);
2755 
2756 		fifo_list = &txq->txq_fifo[txq->txq_tailidx];
2757 		if (list_empty(fifo_list)) {
2758 			ath_txq_unlock(sc, txq);
2759 			return;
2760 		}
2761 
2762 		bf = list_first_entry(fifo_list, struct ath_buf, list);
2763 		if (bf->bf_state.stale) {
2764 			list_del(&bf->list);
2765 			ath_tx_return_buffer(sc, bf);
2766 			bf = list_first_entry(fifo_list, struct ath_buf, list);
2767 		}
2768 
2769 		lastbf = bf->bf_lastbf;
2770 
2771 		INIT_LIST_HEAD(&bf_head);
2772 		if (list_is_last(&lastbf->list, fifo_list)) {
2773 			list_splice_tail_init(fifo_list, &bf_head);
2774 			INCR(txq->txq_tailidx, ATH_TXFIFO_DEPTH);
2775 
2776 			if (!list_empty(&txq->axq_q)) {
2777 				struct list_head bf_q;
2778 
2779 				INIT_LIST_HEAD(&bf_q);
2780 				txq->axq_link = NULL;
2781 				list_splice_tail_init(&txq->axq_q, &bf_q);
2782 				ath_tx_txqaddbuf(sc, txq, &bf_q, true);
2783 			}
2784 		} else {
2785 			lastbf->bf_state.stale = true;
2786 			if (bf != lastbf)
2787 				list_cut_position(&bf_head, fifo_list,
2788 						  lastbf->list.prev);
2789 		}
2790 
2791 		ath_tx_process_buffer(sc, txq, &ts, bf, &bf_head);
2792 		ath_txq_unlock_complete(sc, txq);
2793 	}
2794 }
2795 
2796 /*****************/
2797 /* Init, Cleanup */
2798 /*****************/
2799 
2800 static int ath_txstatus_setup(struct ath_softc *sc, int size)
2801 {
2802 	struct ath_descdma *dd = &sc->txsdma;
2803 	u8 txs_len = sc->sc_ah->caps.txs_len;
2804 
2805 	dd->dd_desc_len = size * txs_len;
2806 	dd->dd_desc = dmam_alloc_coherent(sc->dev, dd->dd_desc_len,
2807 					  &dd->dd_desc_paddr, GFP_KERNEL);
2808 	if (!dd->dd_desc)
2809 		return -ENOMEM;
2810 
2811 	return 0;
2812 }
2813 
2814 static int ath_tx_edma_init(struct ath_softc *sc)
2815 {
2816 	int err;
2817 
2818 	err = ath_txstatus_setup(sc, ATH_TXSTATUS_RING_SIZE);
2819 	if (!err)
2820 		ath9k_hw_setup_statusring(sc->sc_ah, sc->txsdma.dd_desc,
2821 					  sc->txsdma.dd_desc_paddr,
2822 					  ATH_TXSTATUS_RING_SIZE);
2823 
2824 	return err;
2825 }
2826 
2827 int ath_tx_init(struct ath_softc *sc, int nbufs)
2828 {
2829 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2830 	int error = 0;
2831 
2832 	spin_lock_init(&sc->tx.txbuflock);
2833 
2834 	error = ath_descdma_setup(sc, &sc->tx.txdma, &sc->tx.txbuf,
2835 				  "tx", nbufs, 1, 1);
2836 	if (error != 0) {
2837 		ath_err(common,
2838 			"Failed to allocate tx descriptors: %d\n", error);
2839 		return error;
2840 	}
2841 
2842 	error = ath_descdma_setup(sc, &sc->beacon.bdma, &sc->beacon.bbuf,
2843 				  "beacon", ATH_BCBUF, 1, 1);
2844 	if (error != 0) {
2845 		ath_err(common,
2846 			"Failed to allocate beacon descriptors: %d\n", error);
2847 		return error;
2848 	}
2849 
2850 	INIT_DELAYED_WORK(&sc->tx_complete_work, ath_tx_complete_poll_work);
2851 
2852 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
2853 		error = ath_tx_edma_init(sc);
2854 
2855 	return error;
2856 }
2857 
2858 void ath_tx_node_init(struct ath_softc *sc, struct ath_node *an)
2859 {
2860 	struct ath_atx_tid *tid;
2861 	struct ath_atx_ac *ac;
2862 	int tidno, acno;
2863 
2864 	for (tidno = 0, tid = &an->tid[tidno];
2865 	     tidno < IEEE80211_NUM_TIDS;
2866 	     tidno++, tid++) {
2867 		tid->an        = an;
2868 		tid->tidno     = tidno;
2869 		tid->seq_start = tid->seq_next = 0;
2870 		tid->baw_size  = WME_MAX_BA;
2871 		tid->baw_head  = tid->baw_tail = 0;
2872 		tid->sched     = false;
2873 		tid->active	   = false;
2874 		__skb_queue_head_init(&tid->buf_q);
2875 		__skb_queue_head_init(&tid->retry_q);
2876 		acno = TID_TO_WME_AC(tidno);
2877 		tid->ac = &an->ac[acno];
2878 	}
2879 
2880 	for (acno = 0, ac = &an->ac[acno];
2881 	     acno < IEEE80211_NUM_ACS; acno++, ac++) {
2882 		ac->sched    = false;
2883 		ac->clear_ps_filter = true;
2884 		ac->txq = sc->tx.txq_map[acno];
2885 		INIT_LIST_HEAD(&ac->tid_q);
2886 	}
2887 }
2888 
2889 void ath_tx_node_cleanup(struct ath_softc *sc, struct ath_node *an)
2890 {
2891 	struct ath_atx_ac *ac;
2892 	struct ath_atx_tid *tid;
2893 	struct ath_txq *txq;
2894 	int tidno;
2895 
2896 	for (tidno = 0, tid = &an->tid[tidno];
2897 	     tidno < IEEE80211_NUM_TIDS; tidno++, tid++) {
2898 
2899 		ac = tid->ac;
2900 		txq = ac->txq;
2901 
2902 		ath_txq_lock(sc, txq);
2903 
2904 		if (tid->sched) {
2905 			list_del(&tid->list);
2906 			tid->sched = false;
2907 		}
2908 
2909 		if (ac->sched) {
2910 			list_del(&ac->list);
2911 			tid->ac->sched = false;
2912 		}
2913 
2914 		ath_tid_drain(sc, txq, tid);
2915 		tid->active = false;
2916 
2917 		ath_txq_unlock(sc, txq);
2918 	}
2919 }
2920 
2921 #ifdef CONFIG_ATH9K_TX99
2922 
2923 int ath9k_tx99_send(struct ath_softc *sc, struct sk_buff *skb,
2924 		    struct ath_tx_control *txctl)
2925 {
2926 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2927 	struct ath_frame_info *fi = get_frame_info(skb);
2928 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2929 	struct ath_buf *bf;
2930 	int padpos, padsize;
2931 
2932 	padpos = ieee80211_hdrlen(hdr->frame_control);
2933 	padsize = padpos & 3;
2934 
2935 	if (padsize && skb->len > padpos) {
2936 		if (skb_headroom(skb) < padsize) {
2937 			ath_dbg(common, XMIT,
2938 				"tx99 padding failed\n");
2939 		return -EINVAL;
2940 		}
2941 
2942 		skb_push(skb, padsize);
2943 		memmove(skb->data, skb->data + padsize, padpos);
2944 	}
2945 
2946 	fi->keyix = ATH9K_TXKEYIX_INVALID;
2947 	fi->framelen = skb->len + FCS_LEN;
2948 	fi->keytype = ATH9K_KEY_TYPE_CLEAR;
2949 
2950 	bf = ath_tx_setup_buffer(sc, txctl->txq, NULL, skb);
2951 	if (!bf) {
2952 		ath_dbg(common, XMIT, "tx99 buffer setup failed\n");
2953 		return -EINVAL;
2954 	}
2955 
2956 	ath_set_rates(sc->tx99_vif, NULL, bf);
2957 
2958 	ath9k_hw_set_desc_link(sc->sc_ah, bf->bf_desc, bf->bf_daddr);
2959 	ath9k_hw_tx99_start(sc->sc_ah, txctl->txq->axq_qnum);
2960 
2961 	ath_tx_send_normal(sc, txctl->txq, NULL, skb);
2962 
2963 	return 0;
2964 }
2965 
2966 #endif /* CONFIG_ATH9K_TX99 */
2967