xref: /linux/drivers/net/wireless/ath/ath9k/xmit.c (revision f49f4ab95c301dbccad0efe85296d908b8ae7ad4)
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 #define IS_HT_RATE(_rate)     ((_rate) & 0x80)
51 
52 static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
53 			       struct ath_atx_tid *tid, struct sk_buff *skb);
54 static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
55 			    int tx_flags, struct ath_txq *txq);
56 static void ath_tx_complete_buf(struct ath_softc *sc, struct ath_buf *bf,
57 				struct ath_txq *txq, struct list_head *bf_q,
58 				struct ath_tx_status *ts, int txok);
59 static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq,
60 			     struct list_head *head, bool internal);
61 static void ath_tx_rc_status(struct ath_softc *sc, struct ath_buf *bf,
62 			     struct ath_tx_status *ts, int nframes, int nbad,
63 			     int txok);
64 static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
65 			      int seqno);
66 static struct ath_buf *ath_tx_setup_buffer(struct ath_softc *sc,
67 					   struct ath_txq *txq,
68 					   struct ath_atx_tid *tid,
69 					   struct sk_buff *skb);
70 
71 enum {
72 	MCS_HT20,
73 	MCS_HT20_SGI,
74 	MCS_HT40,
75 	MCS_HT40_SGI,
76 };
77 
78 /*********************/
79 /* Aggregation logic */
80 /*********************/
81 
82 void ath_txq_lock(struct ath_softc *sc, struct ath_txq *txq)
83 	__acquires(&txq->axq_lock)
84 {
85 	spin_lock_bh(&txq->axq_lock);
86 }
87 
88 void ath_txq_unlock(struct ath_softc *sc, struct ath_txq *txq)
89 	__releases(&txq->axq_lock)
90 {
91 	spin_unlock_bh(&txq->axq_lock);
92 }
93 
94 void ath_txq_unlock_complete(struct ath_softc *sc, struct ath_txq *txq)
95 	__releases(&txq->axq_lock)
96 {
97 	struct sk_buff_head q;
98 	struct sk_buff *skb;
99 
100 	__skb_queue_head_init(&q);
101 	skb_queue_splice_init(&txq->complete_q, &q);
102 	spin_unlock_bh(&txq->axq_lock);
103 
104 	while ((skb = __skb_dequeue(&q)))
105 		ieee80211_tx_status(sc->hw, skb);
106 }
107 
108 static void ath_tx_queue_tid(struct ath_txq *txq, struct ath_atx_tid *tid)
109 {
110 	struct ath_atx_ac *ac = tid->ac;
111 
112 	if (tid->paused)
113 		return;
114 
115 	if (tid->sched)
116 		return;
117 
118 	tid->sched = true;
119 	list_add_tail(&tid->list, &ac->tid_q);
120 
121 	if (ac->sched)
122 		return;
123 
124 	ac->sched = true;
125 	list_add_tail(&ac->list, &txq->axq_acq);
126 }
127 
128 static void ath_tx_resume_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
129 {
130 	struct ath_txq *txq = tid->ac->txq;
131 
132 	WARN_ON(!tid->paused);
133 
134 	ath_txq_lock(sc, txq);
135 	tid->paused = false;
136 
137 	if (skb_queue_empty(&tid->buf_q))
138 		goto unlock;
139 
140 	ath_tx_queue_tid(txq, tid);
141 	ath_txq_schedule(sc, txq);
142 unlock:
143 	ath_txq_unlock_complete(sc, txq);
144 }
145 
146 static struct ath_frame_info *get_frame_info(struct sk_buff *skb)
147 {
148 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
149 	BUILD_BUG_ON(sizeof(struct ath_frame_info) >
150 		     sizeof(tx_info->rate_driver_data));
151 	return (struct ath_frame_info *) &tx_info->rate_driver_data[0];
152 }
153 
154 static void ath_send_bar(struct ath_atx_tid *tid, u16 seqno)
155 {
156 	ieee80211_send_bar(tid->an->vif, tid->an->sta->addr, tid->tidno,
157 			   seqno << IEEE80211_SEQ_SEQ_SHIFT);
158 }
159 
160 static void ath_tx_flush_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
161 {
162 	struct ath_txq *txq = tid->ac->txq;
163 	struct sk_buff *skb;
164 	struct ath_buf *bf;
165 	struct list_head bf_head;
166 	struct ath_tx_status ts;
167 	struct ath_frame_info *fi;
168 	bool sendbar = false;
169 
170 	INIT_LIST_HEAD(&bf_head);
171 
172 	memset(&ts, 0, sizeof(ts));
173 
174 	while ((skb = __skb_dequeue(&tid->buf_q))) {
175 		fi = get_frame_info(skb);
176 		bf = fi->bf;
177 
178 		if (!bf) {
179 			bf = ath_tx_setup_buffer(sc, txq, tid, skb);
180 			if (!bf) {
181 				ieee80211_free_txskb(sc->hw, skb);
182 				continue;
183 			}
184 		}
185 
186 		if (fi->retries) {
187 			list_add_tail(&bf->list, &bf_head);
188 			ath_tx_update_baw(sc, tid, bf->bf_state.seqno);
189 			ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0);
190 			sendbar = true;
191 		} else {
192 			ath_tx_send_normal(sc, txq, NULL, skb);
193 		}
194 	}
195 
196 	if (tid->baw_head == tid->baw_tail) {
197 		tid->state &= ~AGGR_ADDBA_COMPLETE;
198 		tid->state &= ~AGGR_CLEANUP;
199 	}
200 
201 	if (sendbar) {
202 		ath_txq_unlock(sc, txq);
203 		ath_send_bar(tid, tid->seq_start);
204 		ath_txq_lock(sc, txq);
205 	}
206 }
207 
208 static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
209 			      int seqno)
210 {
211 	int index, cindex;
212 
213 	index  = ATH_BA_INDEX(tid->seq_start, seqno);
214 	cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
215 
216 	__clear_bit(cindex, tid->tx_buf);
217 
218 	while (tid->baw_head != tid->baw_tail && !test_bit(tid->baw_head, tid->tx_buf)) {
219 		INCR(tid->seq_start, IEEE80211_SEQ_MAX);
220 		INCR(tid->baw_head, ATH_TID_MAX_BUFS);
221 		if (tid->bar_index >= 0)
222 			tid->bar_index--;
223 	}
224 }
225 
226 static void ath_tx_addto_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
227 			     u16 seqno)
228 {
229 	int index, cindex;
230 
231 	index  = ATH_BA_INDEX(tid->seq_start, seqno);
232 	cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
233 	__set_bit(cindex, tid->tx_buf);
234 
235 	if (index >= ((tid->baw_tail - tid->baw_head) &
236 		(ATH_TID_MAX_BUFS - 1))) {
237 		tid->baw_tail = cindex;
238 		INCR(tid->baw_tail, ATH_TID_MAX_BUFS);
239 	}
240 }
241 
242 /*
243  * TODO: For frame(s) that are in the retry state, we will reuse the
244  * sequence number(s) without setting the retry bit. The
245  * alternative is to give up on these and BAR the receiver's window
246  * forward.
247  */
248 static void ath_tid_drain(struct ath_softc *sc, struct ath_txq *txq,
249 			  struct ath_atx_tid *tid)
250 
251 {
252 	struct sk_buff *skb;
253 	struct ath_buf *bf;
254 	struct list_head bf_head;
255 	struct ath_tx_status ts;
256 	struct ath_frame_info *fi;
257 
258 	memset(&ts, 0, sizeof(ts));
259 	INIT_LIST_HEAD(&bf_head);
260 
261 	while ((skb = __skb_dequeue(&tid->buf_q))) {
262 		fi = get_frame_info(skb);
263 		bf = fi->bf;
264 
265 		if (!bf) {
266 			ath_tx_complete(sc, skb, ATH_TX_ERROR, txq);
267 			continue;
268 		}
269 
270 		list_add_tail(&bf->list, &bf_head);
271 
272 		if (fi->retries)
273 			ath_tx_update_baw(sc, tid, bf->bf_state.seqno);
274 
275 		ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0);
276 	}
277 
278 	tid->seq_next = tid->seq_start;
279 	tid->baw_tail = tid->baw_head;
280 	tid->bar_index = -1;
281 }
282 
283 static void ath_tx_set_retry(struct ath_softc *sc, struct ath_txq *txq,
284 			     struct sk_buff *skb, int count)
285 {
286 	struct ath_frame_info *fi = get_frame_info(skb);
287 	struct ath_buf *bf = fi->bf;
288 	struct ieee80211_hdr *hdr;
289 	int prev = fi->retries;
290 
291 	TX_STAT_INC(txq->axq_qnum, a_retries);
292 	fi->retries += count;
293 
294 	if (prev > 0)
295 		return;
296 
297 	hdr = (struct ieee80211_hdr *)skb->data;
298 	hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_RETRY);
299 	dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
300 		sizeof(*hdr), DMA_TO_DEVICE);
301 }
302 
303 static struct ath_buf *ath_tx_get_buffer(struct ath_softc *sc)
304 {
305 	struct ath_buf *bf = NULL;
306 
307 	spin_lock_bh(&sc->tx.txbuflock);
308 
309 	if (unlikely(list_empty(&sc->tx.txbuf))) {
310 		spin_unlock_bh(&sc->tx.txbuflock);
311 		return NULL;
312 	}
313 
314 	bf = list_first_entry(&sc->tx.txbuf, struct ath_buf, list);
315 	list_del(&bf->list);
316 
317 	spin_unlock_bh(&sc->tx.txbuflock);
318 
319 	return bf;
320 }
321 
322 static void ath_tx_return_buffer(struct ath_softc *sc, struct ath_buf *bf)
323 {
324 	spin_lock_bh(&sc->tx.txbuflock);
325 	list_add_tail(&bf->list, &sc->tx.txbuf);
326 	spin_unlock_bh(&sc->tx.txbuflock);
327 }
328 
329 static struct ath_buf* ath_clone_txbuf(struct ath_softc *sc, struct ath_buf *bf)
330 {
331 	struct ath_buf *tbf;
332 
333 	tbf = ath_tx_get_buffer(sc);
334 	if (WARN_ON(!tbf))
335 		return NULL;
336 
337 	ATH_TXBUF_RESET(tbf);
338 
339 	tbf->bf_mpdu = bf->bf_mpdu;
340 	tbf->bf_buf_addr = bf->bf_buf_addr;
341 	memcpy(tbf->bf_desc, bf->bf_desc, sc->sc_ah->caps.tx_desc_len);
342 	tbf->bf_state = bf->bf_state;
343 
344 	return tbf;
345 }
346 
347 static void ath_tx_count_frames(struct ath_softc *sc, struct ath_buf *bf,
348 			        struct ath_tx_status *ts, int txok,
349 			        int *nframes, int *nbad)
350 {
351 	struct ath_frame_info *fi;
352 	u16 seq_st = 0;
353 	u32 ba[WME_BA_BMP_SIZE >> 5];
354 	int ba_index;
355 	int isaggr = 0;
356 
357 	*nbad = 0;
358 	*nframes = 0;
359 
360 	isaggr = bf_isaggr(bf);
361 	if (isaggr) {
362 		seq_st = ts->ts_seqnum;
363 		memcpy(ba, &ts->ba_low, WME_BA_BMP_SIZE >> 3);
364 	}
365 
366 	while (bf) {
367 		fi = get_frame_info(bf->bf_mpdu);
368 		ba_index = ATH_BA_INDEX(seq_st, bf->bf_state.seqno);
369 
370 		(*nframes)++;
371 		if (!txok || (isaggr && !ATH_BA_ISSET(ba, ba_index)))
372 			(*nbad)++;
373 
374 		bf = bf->bf_next;
375 	}
376 }
377 
378 
379 static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq,
380 				 struct ath_buf *bf, struct list_head *bf_q,
381 				 struct ath_tx_status *ts, int txok, bool retry)
382 {
383 	struct ath_node *an = NULL;
384 	struct sk_buff *skb;
385 	struct ieee80211_sta *sta;
386 	struct ieee80211_hw *hw = sc->hw;
387 	struct ieee80211_hdr *hdr;
388 	struct ieee80211_tx_info *tx_info;
389 	struct ath_atx_tid *tid = NULL;
390 	struct ath_buf *bf_next, *bf_last = bf->bf_lastbf;
391 	struct list_head bf_head;
392 	struct sk_buff_head bf_pending;
393 	u16 seq_st = 0, acked_cnt = 0, txfail_cnt = 0, seq_first;
394 	u32 ba[WME_BA_BMP_SIZE >> 5];
395 	int isaggr, txfail, txpending, sendbar = 0, needreset = 0, nbad = 0;
396 	bool rc_update = true;
397 	struct ieee80211_tx_rate rates[4];
398 	struct ath_frame_info *fi;
399 	int nframes;
400 	u8 tidno;
401 	bool flush = !!(ts->ts_status & ATH9K_TX_FLUSH);
402 	int i, retries;
403 	int bar_index = -1;
404 
405 	skb = bf->bf_mpdu;
406 	hdr = (struct ieee80211_hdr *)skb->data;
407 
408 	tx_info = IEEE80211_SKB_CB(skb);
409 
410 	memcpy(rates, tx_info->control.rates, sizeof(rates));
411 
412 	retries = ts->ts_longretry + 1;
413 	for (i = 0; i < ts->ts_rateindex; i++)
414 		retries += rates[i].count;
415 
416 	rcu_read_lock();
417 
418 	sta = ieee80211_find_sta_by_ifaddr(hw, hdr->addr1, hdr->addr2);
419 	if (!sta) {
420 		rcu_read_unlock();
421 
422 		INIT_LIST_HEAD(&bf_head);
423 		while (bf) {
424 			bf_next = bf->bf_next;
425 
426 			if (!bf->bf_stale || bf_next != NULL)
427 				list_move_tail(&bf->list, &bf_head);
428 
429 			ath_tx_complete_buf(sc, bf, txq, &bf_head, ts, 0);
430 
431 			bf = bf_next;
432 		}
433 		return;
434 	}
435 
436 	an = (struct ath_node *)sta->drv_priv;
437 	tidno = ieee80211_get_qos_ctl(hdr)[0] & IEEE80211_QOS_CTL_TID_MASK;
438 	tid = ATH_AN_2_TID(an, tidno);
439 	seq_first = tid->seq_start;
440 
441 	/*
442 	 * The hardware occasionally sends a tx status for the wrong TID.
443 	 * In this case, the BA status cannot be considered valid and all
444 	 * subframes need to be retransmitted
445 	 */
446 	if (tidno != ts->tid)
447 		txok = false;
448 
449 	isaggr = bf_isaggr(bf);
450 	memset(ba, 0, WME_BA_BMP_SIZE >> 3);
451 
452 	if (isaggr && txok) {
453 		if (ts->ts_flags & ATH9K_TX_BA) {
454 			seq_st = ts->ts_seqnum;
455 			memcpy(ba, &ts->ba_low, WME_BA_BMP_SIZE >> 3);
456 		} else {
457 			/*
458 			 * AR5416 can become deaf/mute when BA
459 			 * issue happens. Chip needs to be reset.
460 			 * But AP code may have sychronization issues
461 			 * when perform internal reset in this routine.
462 			 * Only enable reset in STA mode for now.
463 			 */
464 			if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION)
465 				needreset = 1;
466 		}
467 	}
468 
469 	__skb_queue_head_init(&bf_pending);
470 
471 	ath_tx_count_frames(sc, bf, ts, txok, &nframes, &nbad);
472 	while (bf) {
473 		u16 seqno = bf->bf_state.seqno;
474 
475 		txfail = txpending = sendbar = 0;
476 		bf_next = bf->bf_next;
477 
478 		skb = bf->bf_mpdu;
479 		tx_info = IEEE80211_SKB_CB(skb);
480 		fi = get_frame_info(skb);
481 
482 		if (ATH_BA_ISSET(ba, ATH_BA_INDEX(seq_st, seqno))) {
483 			/* transmit completion, subframe is
484 			 * acked by block ack */
485 			acked_cnt++;
486 		} else if (!isaggr && txok) {
487 			/* transmit completion */
488 			acked_cnt++;
489 		} else if ((tid->state & AGGR_CLEANUP) || !retry) {
490 			/*
491 			 * cleanup in progress, just fail
492 			 * the un-acked sub-frames
493 			 */
494 			txfail = 1;
495 		} else if (flush) {
496 			txpending = 1;
497 		} else if (fi->retries < ATH_MAX_SW_RETRIES) {
498 			if (txok || !an->sleeping)
499 				ath_tx_set_retry(sc, txq, bf->bf_mpdu,
500 						 retries);
501 
502 			txpending = 1;
503 		} else {
504 			txfail = 1;
505 			txfail_cnt++;
506 			bar_index = max_t(int, bar_index,
507 				ATH_BA_INDEX(seq_first, seqno));
508 		}
509 
510 		/*
511 		 * Make sure the last desc is reclaimed if it
512 		 * not a holding desc.
513 		 */
514 		INIT_LIST_HEAD(&bf_head);
515 		if ((sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) ||
516 		    bf_next != NULL || !bf_last->bf_stale)
517 			list_move_tail(&bf->list, &bf_head);
518 
519 		if (!txpending || (tid->state & AGGR_CLEANUP)) {
520 			/*
521 			 * complete the acked-ones/xretried ones; update
522 			 * block-ack window
523 			 */
524 			ath_tx_update_baw(sc, tid, seqno);
525 
526 			if (rc_update && (acked_cnt == 1 || txfail_cnt == 1)) {
527 				memcpy(tx_info->control.rates, rates, sizeof(rates));
528 				ath_tx_rc_status(sc, bf, ts, nframes, nbad, txok);
529 				rc_update = false;
530 			}
531 
532 			ath_tx_complete_buf(sc, bf, txq, &bf_head, ts,
533 				!txfail);
534 		} else {
535 			/* retry the un-acked ones */
536 			if (!(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) &&
537 			    bf->bf_next == NULL && bf_last->bf_stale) {
538 				struct ath_buf *tbf;
539 
540 				tbf = ath_clone_txbuf(sc, bf_last);
541 				/*
542 				 * Update tx baw and complete the
543 				 * frame with failed status if we
544 				 * run out of tx buf.
545 				 */
546 				if (!tbf) {
547 					ath_tx_update_baw(sc, tid, seqno);
548 
549 					ath_tx_complete_buf(sc, bf, txq,
550 							    &bf_head, ts, 0);
551 					bar_index = max_t(int, bar_index,
552 						ATH_BA_INDEX(seq_first, seqno));
553 					break;
554 				}
555 
556 				fi->bf = tbf;
557 			}
558 
559 			/*
560 			 * Put this buffer to the temporary pending
561 			 * queue to retain ordering
562 			 */
563 			__skb_queue_tail(&bf_pending, skb);
564 		}
565 
566 		bf = bf_next;
567 	}
568 
569 	/* prepend un-acked frames to the beginning of the pending frame queue */
570 	if (!skb_queue_empty(&bf_pending)) {
571 		if (an->sleeping)
572 			ieee80211_sta_set_buffered(sta, tid->tidno, true);
573 
574 		skb_queue_splice(&bf_pending, &tid->buf_q);
575 		if (!an->sleeping) {
576 			ath_tx_queue_tid(txq, tid);
577 
578 			if (ts->ts_status & (ATH9K_TXERR_FILT | ATH9K_TXERR_XRETRY))
579 				tid->ac->clear_ps_filter = true;
580 		}
581 	}
582 
583 	if (bar_index >= 0) {
584 		u16 bar_seq = ATH_BA_INDEX2SEQ(seq_first, bar_index);
585 
586 		if (BAW_WITHIN(tid->seq_start, tid->baw_size, bar_seq))
587 			tid->bar_index = ATH_BA_INDEX(tid->seq_start, bar_seq);
588 
589 		ath_txq_unlock(sc, txq);
590 		ath_send_bar(tid, ATH_BA_INDEX2SEQ(seq_first, bar_index + 1));
591 		ath_txq_lock(sc, txq);
592 	}
593 
594 	if (tid->state & AGGR_CLEANUP)
595 		ath_tx_flush_tid(sc, tid);
596 
597 	rcu_read_unlock();
598 
599 	if (needreset)
600 		ath9k_queue_reset(sc, RESET_TYPE_TX_ERROR);
601 }
602 
603 static bool ath_lookup_legacy(struct ath_buf *bf)
604 {
605 	struct sk_buff *skb;
606 	struct ieee80211_tx_info *tx_info;
607 	struct ieee80211_tx_rate *rates;
608 	int i;
609 
610 	skb = bf->bf_mpdu;
611 	tx_info = IEEE80211_SKB_CB(skb);
612 	rates = tx_info->control.rates;
613 
614 	for (i = 0; i < 4; i++) {
615 		if (!rates[i].count || rates[i].idx < 0)
616 			break;
617 
618 		if (!(rates[i].flags & IEEE80211_TX_RC_MCS))
619 			return true;
620 	}
621 
622 	return false;
623 }
624 
625 static u32 ath_lookup_rate(struct ath_softc *sc, struct ath_buf *bf,
626 			   struct ath_atx_tid *tid)
627 {
628 	struct sk_buff *skb;
629 	struct ieee80211_tx_info *tx_info;
630 	struct ieee80211_tx_rate *rates;
631 	u32 max_4ms_framelen, frmlen;
632 	u16 aggr_limit, bt_aggr_limit, legacy = 0;
633 	int q = tid->ac->txq->mac80211_qnum;
634 	int i;
635 
636 	skb = bf->bf_mpdu;
637 	tx_info = IEEE80211_SKB_CB(skb);
638 	rates = tx_info->control.rates;
639 
640 	/*
641 	 * Find the lowest frame length among the rate series that will have a
642 	 * 4ms (or TXOP limited) transmit duration.
643 	 */
644 	max_4ms_framelen = ATH_AMPDU_LIMIT_MAX;
645 
646 	for (i = 0; i < 4; i++) {
647 		int modeidx;
648 
649 		if (!rates[i].count)
650 			continue;
651 
652 		if (!(rates[i].flags & IEEE80211_TX_RC_MCS)) {
653 			legacy = 1;
654 			break;
655 		}
656 
657 		if (rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
658 			modeidx = MCS_HT40;
659 		else
660 			modeidx = MCS_HT20;
661 
662 		if (rates[i].flags & IEEE80211_TX_RC_SHORT_GI)
663 			modeidx++;
664 
665 		frmlen = sc->tx.max_aggr_framelen[q][modeidx][rates[i].idx];
666 		max_4ms_framelen = min(max_4ms_framelen, frmlen);
667 	}
668 
669 	/*
670 	 * limit aggregate size by the minimum rate if rate selected is
671 	 * not a probe rate, if rate selected is a probe rate then
672 	 * avoid aggregation of this packet.
673 	 */
674 	if (tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE || legacy)
675 		return 0;
676 
677 	aggr_limit = min(max_4ms_framelen, (u32)ATH_AMPDU_LIMIT_MAX);
678 
679 	/*
680 	 * Override the default aggregation limit for BTCOEX.
681 	 */
682 	bt_aggr_limit = ath9k_btcoex_aggr_limit(sc, max_4ms_framelen);
683 	if (bt_aggr_limit)
684 		aggr_limit = bt_aggr_limit;
685 
686 	/*
687 	 * h/w can accept aggregates up to 16 bit lengths (65535).
688 	 * The IE, however can hold up to 65536, which shows up here
689 	 * as zero. Ignore 65536 since we  are constrained by hw.
690 	 */
691 	if (tid->an->maxampdu)
692 		aggr_limit = min(aggr_limit, tid->an->maxampdu);
693 
694 	return aggr_limit;
695 }
696 
697 /*
698  * Returns the number of delimiters to be added to
699  * meet the minimum required mpdudensity.
700  */
701 static int ath_compute_num_delims(struct ath_softc *sc, struct ath_atx_tid *tid,
702 				  struct ath_buf *bf, u16 frmlen,
703 				  bool first_subfrm)
704 {
705 #define FIRST_DESC_NDELIMS 60
706 	struct sk_buff *skb = bf->bf_mpdu;
707 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
708 	u32 nsymbits, nsymbols;
709 	u16 minlen;
710 	u8 flags, rix;
711 	int width, streams, half_gi, ndelim, mindelim;
712 	struct ath_frame_info *fi = get_frame_info(bf->bf_mpdu);
713 
714 	/* Select standard number of delimiters based on frame length alone */
715 	ndelim = ATH_AGGR_GET_NDELIM(frmlen);
716 
717 	/*
718 	 * If encryption enabled, hardware requires some more padding between
719 	 * subframes.
720 	 * TODO - this could be improved to be dependent on the rate.
721 	 *      The hardware can keep up at lower rates, but not higher rates
722 	 */
723 	if ((fi->keyix != ATH9K_TXKEYIX_INVALID) &&
724 	    !(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA))
725 		ndelim += ATH_AGGR_ENCRYPTDELIM;
726 
727 	/*
728 	 * Add delimiter when using RTS/CTS with aggregation
729 	 * and non enterprise AR9003 card
730 	 */
731 	if (first_subfrm && !AR_SREV_9580_10_OR_LATER(sc->sc_ah) &&
732 	    (sc->sc_ah->ent_mode & AR_ENT_OTP_MIN_PKT_SIZE_DISABLE))
733 		ndelim = max(ndelim, FIRST_DESC_NDELIMS);
734 
735 	/*
736 	 * Convert desired mpdu density from microeconds to bytes based
737 	 * on highest rate in rate series (i.e. first rate) to determine
738 	 * required minimum length for subframe. Take into account
739 	 * whether high rate is 20 or 40Mhz and half or full GI.
740 	 *
741 	 * If there is no mpdu density restriction, no further calculation
742 	 * is needed.
743 	 */
744 
745 	if (tid->an->mpdudensity == 0)
746 		return ndelim;
747 
748 	rix = tx_info->control.rates[0].idx;
749 	flags = tx_info->control.rates[0].flags;
750 	width = (flags & IEEE80211_TX_RC_40_MHZ_WIDTH) ? 1 : 0;
751 	half_gi = (flags & IEEE80211_TX_RC_SHORT_GI) ? 1 : 0;
752 
753 	if (half_gi)
754 		nsymbols = NUM_SYMBOLS_PER_USEC_HALFGI(tid->an->mpdudensity);
755 	else
756 		nsymbols = NUM_SYMBOLS_PER_USEC(tid->an->mpdudensity);
757 
758 	if (nsymbols == 0)
759 		nsymbols = 1;
760 
761 	streams = HT_RC_2_STREAMS(rix);
762 	nsymbits = bits_per_symbol[rix % 8][width] * streams;
763 	minlen = (nsymbols * nsymbits) / BITS_PER_BYTE;
764 
765 	if (frmlen < minlen) {
766 		mindelim = (minlen - frmlen) / ATH_AGGR_DELIM_SZ;
767 		ndelim = max(mindelim, ndelim);
768 	}
769 
770 	return ndelim;
771 }
772 
773 static enum ATH_AGGR_STATUS ath_tx_form_aggr(struct ath_softc *sc,
774 					     struct ath_txq *txq,
775 					     struct ath_atx_tid *tid,
776 					     struct list_head *bf_q,
777 					     int *aggr_len)
778 {
779 #define PADBYTES(_len) ((4 - ((_len) % 4)) % 4)
780 	struct ath_buf *bf, *bf_first = NULL, *bf_prev = NULL;
781 	int rl = 0, nframes = 0, ndelim, prev_al = 0;
782 	u16 aggr_limit = 0, al = 0, bpad = 0,
783 		al_delta, h_baw = tid->baw_size / 2;
784 	enum ATH_AGGR_STATUS status = ATH_AGGR_DONE;
785 	struct ieee80211_tx_info *tx_info;
786 	struct ath_frame_info *fi;
787 	struct sk_buff *skb;
788 	u16 seqno;
789 
790 	do {
791 		skb = skb_peek(&tid->buf_q);
792 		fi = get_frame_info(skb);
793 		bf = fi->bf;
794 		if (!fi->bf)
795 			bf = ath_tx_setup_buffer(sc, txq, tid, skb);
796 
797 		if (!bf) {
798 			__skb_unlink(skb, &tid->buf_q);
799 			ieee80211_free_txskb(sc->hw, skb);
800 			continue;
801 		}
802 
803 		bf->bf_state.bf_type = BUF_AMPDU | BUF_AGGR;
804 		seqno = bf->bf_state.seqno;
805 
806 		/* do not step over block-ack window */
807 		if (!BAW_WITHIN(tid->seq_start, tid->baw_size, seqno)) {
808 			status = ATH_AGGR_BAW_CLOSED;
809 			break;
810 		}
811 
812 		if (tid->bar_index > ATH_BA_INDEX(tid->seq_start, seqno)) {
813 			struct ath_tx_status ts = {};
814 			struct list_head bf_head;
815 
816 			INIT_LIST_HEAD(&bf_head);
817 			list_add(&bf->list, &bf_head);
818 			__skb_unlink(skb, &tid->buf_q);
819 			ath_tx_update_baw(sc, tid, seqno);
820 			ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0);
821 			continue;
822 		}
823 
824 		if (!bf_first)
825 			bf_first = bf;
826 
827 		if (!rl) {
828 			aggr_limit = ath_lookup_rate(sc, bf, tid);
829 			rl = 1;
830 		}
831 
832 		/* do not exceed aggregation limit */
833 		al_delta = ATH_AGGR_DELIM_SZ + fi->framelen;
834 
835 		if (nframes &&
836 		    ((aggr_limit < (al + bpad + al_delta + prev_al)) ||
837 		     ath_lookup_legacy(bf))) {
838 			status = ATH_AGGR_LIMITED;
839 			break;
840 		}
841 
842 		tx_info = IEEE80211_SKB_CB(bf->bf_mpdu);
843 		if (nframes && (tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE))
844 			break;
845 
846 		/* do not exceed subframe limit */
847 		if (nframes >= min((int)h_baw, ATH_AMPDU_SUBFRAME_DEFAULT)) {
848 			status = ATH_AGGR_LIMITED;
849 			break;
850 		}
851 
852 		/* add padding for previous frame to aggregation length */
853 		al += bpad + al_delta;
854 
855 		/*
856 		 * Get the delimiters needed to meet the MPDU
857 		 * density for this node.
858 		 */
859 		ndelim = ath_compute_num_delims(sc, tid, bf_first, fi->framelen,
860 						!nframes);
861 		bpad = PADBYTES(al_delta) + (ndelim << 2);
862 
863 		nframes++;
864 		bf->bf_next = NULL;
865 
866 		/* link buffers of this frame to the aggregate */
867 		if (!fi->retries)
868 			ath_tx_addto_baw(sc, tid, seqno);
869 		bf->bf_state.ndelim = ndelim;
870 
871 		__skb_unlink(skb, &tid->buf_q);
872 		list_add_tail(&bf->list, bf_q);
873 		if (bf_prev)
874 			bf_prev->bf_next = bf;
875 
876 		bf_prev = bf;
877 
878 	} while (!skb_queue_empty(&tid->buf_q));
879 
880 	*aggr_len = al;
881 
882 	return status;
883 #undef PADBYTES
884 }
885 
886 /*
887  * rix - rate index
888  * pktlen - total bytes (delims + data + fcs + pads + pad delims)
889  * width  - 0 for 20 MHz, 1 for 40 MHz
890  * half_gi - to use 4us v/s 3.6 us for symbol time
891  */
892 static u32 ath_pkt_duration(struct ath_softc *sc, u8 rix, int pktlen,
893 			    int width, int half_gi, bool shortPreamble)
894 {
895 	u32 nbits, nsymbits, duration, nsymbols;
896 	int streams;
897 
898 	/* find number of symbols: PLCP + data */
899 	streams = HT_RC_2_STREAMS(rix);
900 	nbits = (pktlen << 3) + OFDM_PLCP_BITS;
901 	nsymbits = bits_per_symbol[rix % 8][width] * streams;
902 	nsymbols = (nbits + nsymbits - 1) / nsymbits;
903 
904 	if (!half_gi)
905 		duration = SYMBOL_TIME(nsymbols);
906 	else
907 		duration = SYMBOL_TIME_HALFGI(nsymbols);
908 
909 	/* addup duration for legacy/ht training and signal fields */
910 	duration += L_STF + L_LTF + L_SIG + HT_SIG + HT_STF + HT_LTF(streams);
911 
912 	return duration;
913 }
914 
915 static int ath_max_framelen(int usec, int mcs, bool ht40, bool sgi)
916 {
917 	int streams = HT_RC_2_STREAMS(mcs);
918 	int symbols, bits;
919 	int bytes = 0;
920 
921 	symbols = sgi ? TIME_SYMBOLS_HALFGI(usec) : TIME_SYMBOLS(usec);
922 	bits = symbols * bits_per_symbol[mcs % 8][ht40] * streams;
923 	bits -= OFDM_PLCP_BITS;
924 	bytes = bits / 8;
925 	bytes -= L_STF + L_LTF + L_SIG + HT_SIG + HT_STF + HT_LTF(streams);
926 	if (bytes > 65532)
927 		bytes = 65532;
928 
929 	return bytes;
930 }
931 
932 void ath_update_max_aggr_framelen(struct ath_softc *sc, int queue, int txop)
933 {
934 	u16 *cur_ht20, *cur_ht20_sgi, *cur_ht40, *cur_ht40_sgi;
935 	int mcs;
936 
937 	/* 4ms is the default (and maximum) duration */
938 	if (!txop || txop > 4096)
939 		txop = 4096;
940 
941 	cur_ht20 = sc->tx.max_aggr_framelen[queue][MCS_HT20];
942 	cur_ht20_sgi = sc->tx.max_aggr_framelen[queue][MCS_HT20_SGI];
943 	cur_ht40 = sc->tx.max_aggr_framelen[queue][MCS_HT40];
944 	cur_ht40_sgi = sc->tx.max_aggr_framelen[queue][MCS_HT40_SGI];
945 	for (mcs = 0; mcs < 32; mcs++) {
946 		cur_ht20[mcs] = ath_max_framelen(txop, mcs, false, false);
947 		cur_ht20_sgi[mcs] = ath_max_framelen(txop, mcs, false, true);
948 		cur_ht40[mcs] = ath_max_framelen(txop, mcs, true, false);
949 		cur_ht40_sgi[mcs] = ath_max_framelen(txop, mcs, true, true);
950 	}
951 }
952 
953 static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf,
954 			     struct ath_tx_info *info, int len)
955 {
956 	struct ath_hw *ah = sc->sc_ah;
957 	struct sk_buff *skb;
958 	struct ieee80211_tx_info *tx_info;
959 	struct ieee80211_tx_rate *rates;
960 	const struct ieee80211_rate *rate;
961 	struct ieee80211_hdr *hdr;
962 	struct ath_frame_info *fi = get_frame_info(bf->bf_mpdu);
963 	int i;
964 	u8 rix = 0;
965 
966 	skb = bf->bf_mpdu;
967 	tx_info = IEEE80211_SKB_CB(skb);
968 	rates = tx_info->control.rates;
969 	hdr = (struct ieee80211_hdr *)skb->data;
970 
971 	/* set dur_update_en for l-sig computation except for PS-Poll frames */
972 	info->dur_update = !ieee80211_is_pspoll(hdr->frame_control);
973 	info->rtscts_rate = fi->rtscts_rate;
974 
975 	for (i = 0; i < 4; i++) {
976 		bool is_40, is_sgi, is_sp;
977 		int phy;
978 
979 		if (!rates[i].count || (rates[i].idx < 0))
980 			continue;
981 
982 		rix = rates[i].idx;
983 		info->rates[i].Tries = rates[i].count;
984 
985 		    if (rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) {
986 			info->rates[i].RateFlags |= ATH9K_RATESERIES_RTS_CTS;
987 			info->flags |= ATH9K_TXDESC_RTSENA;
988 		} else if (rates[i].flags & IEEE80211_TX_RC_USE_CTS_PROTECT) {
989 			info->rates[i].RateFlags |= ATH9K_RATESERIES_RTS_CTS;
990 			info->flags |= ATH9K_TXDESC_CTSENA;
991 		}
992 
993 		if (rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
994 			info->rates[i].RateFlags |= ATH9K_RATESERIES_2040;
995 		if (rates[i].flags & IEEE80211_TX_RC_SHORT_GI)
996 			info->rates[i].RateFlags |= ATH9K_RATESERIES_HALFGI;
997 
998 		is_sgi = !!(rates[i].flags & IEEE80211_TX_RC_SHORT_GI);
999 		is_40 = !!(rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH);
1000 		is_sp = !!(rates[i].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
1001 
1002 		if (rates[i].flags & IEEE80211_TX_RC_MCS) {
1003 			/* MCS rates */
1004 			info->rates[i].Rate = rix | 0x80;
1005 			info->rates[i].ChSel = ath_txchainmask_reduction(sc,
1006 					ah->txchainmask, info->rates[i].Rate);
1007 			info->rates[i].PktDuration = ath_pkt_duration(sc, rix, len,
1008 				 is_40, is_sgi, is_sp);
1009 			if (rix < 8 && (tx_info->flags & IEEE80211_TX_CTL_STBC))
1010 				info->rates[i].RateFlags |= ATH9K_RATESERIES_STBC;
1011 			continue;
1012 		}
1013 
1014 		/* legacy rates */
1015 		rate = &sc->sbands[tx_info->band].bitrates[rates[i].idx];
1016 		if ((tx_info->band == IEEE80211_BAND_2GHZ) &&
1017 		    !(rate->flags & IEEE80211_RATE_ERP_G))
1018 			phy = WLAN_RC_PHY_CCK;
1019 		else
1020 			phy = WLAN_RC_PHY_OFDM;
1021 
1022 		info->rates[i].Rate = rate->hw_value;
1023 		if (rate->hw_value_short) {
1024 			if (rates[i].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
1025 				info->rates[i].Rate |= rate->hw_value_short;
1026 		} else {
1027 			is_sp = false;
1028 		}
1029 
1030 		if (bf->bf_state.bfs_paprd)
1031 			info->rates[i].ChSel = ah->txchainmask;
1032 		else
1033 			info->rates[i].ChSel = ath_txchainmask_reduction(sc,
1034 					ah->txchainmask, info->rates[i].Rate);
1035 
1036 		info->rates[i].PktDuration = ath9k_hw_computetxtime(sc->sc_ah,
1037 			phy, rate->bitrate * 100, len, rix, is_sp);
1038 	}
1039 
1040 	/* For AR5416 - RTS cannot be followed by a frame larger than 8K */
1041 	if (bf_isaggr(bf) && (len > sc->sc_ah->caps.rts_aggr_limit))
1042 		info->flags &= ~ATH9K_TXDESC_RTSENA;
1043 
1044 	/* ATH9K_TXDESC_RTSENA and ATH9K_TXDESC_CTSENA are mutually exclusive. */
1045 	if (info->flags & ATH9K_TXDESC_RTSENA)
1046 		info->flags &= ~ATH9K_TXDESC_CTSENA;
1047 }
1048 
1049 static enum ath9k_pkt_type get_hw_packet_type(struct sk_buff *skb)
1050 {
1051 	struct ieee80211_hdr *hdr;
1052 	enum ath9k_pkt_type htype;
1053 	__le16 fc;
1054 
1055 	hdr = (struct ieee80211_hdr *)skb->data;
1056 	fc = hdr->frame_control;
1057 
1058 	if (ieee80211_is_beacon(fc))
1059 		htype = ATH9K_PKT_TYPE_BEACON;
1060 	else if (ieee80211_is_probe_resp(fc))
1061 		htype = ATH9K_PKT_TYPE_PROBE_RESP;
1062 	else if (ieee80211_is_atim(fc))
1063 		htype = ATH9K_PKT_TYPE_ATIM;
1064 	else if (ieee80211_is_pspoll(fc))
1065 		htype = ATH9K_PKT_TYPE_PSPOLL;
1066 	else
1067 		htype = ATH9K_PKT_TYPE_NORMAL;
1068 
1069 	return htype;
1070 }
1071 
1072 static void ath_tx_fill_desc(struct ath_softc *sc, struct ath_buf *bf,
1073 			     struct ath_txq *txq, int len)
1074 {
1075 	struct ath_hw *ah = sc->sc_ah;
1076 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(bf->bf_mpdu);
1077 	struct ath_buf *bf_first = bf;
1078 	struct ath_tx_info info;
1079 	bool aggr = !!(bf->bf_state.bf_type & BUF_AGGR);
1080 
1081 	memset(&info, 0, sizeof(info));
1082 	info.is_first = true;
1083 	info.is_last = true;
1084 	info.txpower = MAX_RATE_POWER;
1085 	info.qcu = txq->axq_qnum;
1086 
1087 	info.flags = ATH9K_TXDESC_INTREQ;
1088 	if (tx_info->flags & IEEE80211_TX_CTL_NO_ACK)
1089 		info.flags |= ATH9K_TXDESC_NOACK;
1090 	if (tx_info->flags & IEEE80211_TX_CTL_LDPC)
1091 		info.flags |= ATH9K_TXDESC_LDPC;
1092 
1093 	ath_buf_set_rate(sc, bf, &info, len);
1094 
1095 	if (tx_info->flags & IEEE80211_TX_CTL_CLEAR_PS_FILT)
1096 		info.flags |= ATH9K_TXDESC_CLRDMASK;
1097 
1098 	if (bf->bf_state.bfs_paprd)
1099 		info.flags |= (u32) bf->bf_state.bfs_paprd << ATH9K_TXDESC_PAPRD_S;
1100 
1101 
1102 	while (bf) {
1103 		struct sk_buff *skb = bf->bf_mpdu;
1104 		struct ath_frame_info *fi = get_frame_info(skb);
1105 
1106 		info.type = get_hw_packet_type(skb);
1107 		if (bf->bf_next)
1108 			info.link = bf->bf_next->bf_daddr;
1109 		else
1110 			info.link = 0;
1111 
1112 		info.buf_addr[0] = bf->bf_buf_addr;
1113 		info.buf_len[0] = skb->len;
1114 		info.pkt_len = fi->framelen;
1115 		info.keyix = fi->keyix;
1116 		info.keytype = fi->keytype;
1117 
1118 		if (aggr) {
1119 			if (bf == bf_first)
1120 				info.aggr = AGGR_BUF_FIRST;
1121 			else if (!bf->bf_next)
1122 				info.aggr = AGGR_BUF_LAST;
1123 			else
1124 				info.aggr = AGGR_BUF_MIDDLE;
1125 
1126 			info.ndelim = bf->bf_state.ndelim;
1127 			info.aggr_len = len;
1128 		}
1129 
1130 		ath9k_hw_set_txdesc(ah, bf->bf_desc, &info);
1131 		bf = bf->bf_next;
1132 	}
1133 }
1134 
1135 static void ath_tx_sched_aggr(struct ath_softc *sc, struct ath_txq *txq,
1136 			      struct ath_atx_tid *tid)
1137 {
1138 	struct ath_buf *bf;
1139 	enum ATH_AGGR_STATUS status;
1140 	struct ieee80211_tx_info *tx_info;
1141 	struct list_head bf_q;
1142 	int aggr_len;
1143 
1144 	do {
1145 		if (skb_queue_empty(&tid->buf_q))
1146 			return;
1147 
1148 		INIT_LIST_HEAD(&bf_q);
1149 
1150 		status = ath_tx_form_aggr(sc, txq, tid, &bf_q, &aggr_len);
1151 
1152 		/*
1153 		 * no frames picked up to be aggregated;
1154 		 * block-ack window is not open.
1155 		 */
1156 		if (list_empty(&bf_q))
1157 			break;
1158 
1159 		bf = list_first_entry(&bf_q, struct ath_buf, list);
1160 		bf->bf_lastbf = list_entry(bf_q.prev, struct ath_buf, list);
1161 		tx_info = IEEE80211_SKB_CB(bf->bf_mpdu);
1162 
1163 		if (tid->ac->clear_ps_filter) {
1164 			tid->ac->clear_ps_filter = false;
1165 			tx_info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1166 		} else {
1167 			tx_info->flags &= ~IEEE80211_TX_CTL_CLEAR_PS_FILT;
1168 		}
1169 
1170 		/* if only one frame, send as non-aggregate */
1171 		if (bf == bf->bf_lastbf) {
1172 			aggr_len = get_frame_info(bf->bf_mpdu)->framelen;
1173 			bf->bf_state.bf_type = BUF_AMPDU;
1174 		} else {
1175 			TX_STAT_INC(txq->axq_qnum, a_aggr);
1176 		}
1177 
1178 		ath_tx_fill_desc(sc, bf, txq, aggr_len);
1179 		ath_tx_txqaddbuf(sc, txq, &bf_q, false);
1180 	} while (txq->axq_ampdu_depth < ATH_AGGR_MIN_QDEPTH &&
1181 		 status != ATH_AGGR_BAW_CLOSED);
1182 }
1183 
1184 int ath_tx_aggr_start(struct ath_softc *sc, struct ieee80211_sta *sta,
1185 		      u16 tid, u16 *ssn)
1186 {
1187 	struct ath_atx_tid *txtid;
1188 	struct ath_node *an;
1189 	u8 density;
1190 
1191 	an = (struct ath_node *)sta->drv_priv;
1192 	txtid = ATH_AN_2_TID(an, tid);
1193 
1194 	if (txtid->state & (AGGR_CLEANUP | AGGR_ADDBA_COMPLETE))
1195 		return -EAGAIN;
1196 
1197 	/* update ampdu factor/density, they may have changed. This may happen
1198 	 * in HT IBSS when a beacon with HT-info is received after the station
1199 	 * has already been added.
1200 	 */
1201 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_HT) {
1202 		an->maxampdu = 1 << (IEEE80211_HT_MAX_AMPDU_FACTOR +
1203 				     sta->ht_cap.ampdu_factor);
1204 		density = ath9k_parse_mpdudensity(sta->ht_cap.ampdu_density);
1205 		an->mpdudensity = density;
1206 	}
1207 
1208 	txtid->state |= AGGR_ADDBA_PROGRESS;
1209 	txtid->paused = true;
1210 	*ssn = txtid->seq_start = txtid->seq_next;
1211 	txtid->bar_index = -1;
1212 
1213 	memset(txtid->tx_buf, 0, sizeof(txtid->tx_buf));
1214 	txtid->baw_head = txtid->baw_tail = 0;
1215 
1216 	return 0;
1217 }
1218 
1219 void ath_tx_aggr_stop(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid)
1220 {
1221 	struct ath_node *an = (struct ath_node *)sta->drv_priv;
1222 	struct ath_atx_tid *txtid = ATH_AN_2_TID(an, tid);
1223 	struct ath_txq *txq = txtid->ac->txq;
1224 
1225 	if (txtid->state & AGGR_CLEANUP)
1226 		return;
1227 
1228 	if (!(txtid->state & AGGR_ADDBA_COMPLETE)) {
1229 		txtid->state &= ~AGGR_ADDBA_PROGRESS;
1230 		return;
1231 	}
1232 
1233 	ath_txq_lock(sc, txq);
1234 	txtid->paused = true;
1235 
1236 	/*
1237 	 * If frames are still being transmitted for this TID, they will be
1238 	 * cleaned up during tx completion. To prevent race conditions, this
1239 	 * TID can only be reused after all in-progress subframes have been
1240 	 * completed.
1241 	 */
1242 	if (txtid->baw_head != txtid->baw_tail)
1243 		txtid->state |= AGGR_CLEANUP;
1244 	else
1245 		txtid->state &= ~AGGR_ADDBA_COMPLETE;
1246 
1247 	ath_tx_flush_tid(sc, txtid);
1248 	ath_txq_unlock_complete(sc, txq);
1249 }
1250 
1251 void ath_tx_aggr_sleep(struct ieee80211_sta *sta, struct ath_softc *sc,
1252 		       struct ath_node *an)
1253 {
1254 	struct ath_atx_tid *tid;
1255 	struct ath_atx_ac *ac;
1256 	struct ath_txq *txq;
1257 	bool buffered;
1258 	int tidno;
1259 
1260 	for (tidno = 0, tid = &an->tid[tidno];
1261 	     tidno < WME_NUM_TID; tidno++, tid++) {
1262 
1263 		if (!tid->sched)
1264 			continue;
1265 
1266 		ac = tid->ac;
1267 		txq = ac->txq;
1268 
1269 		ath_txq_lock(sc, txq);
1270 
1271 		buffered = !skb_queue_empty(&tid->buf_q);
1272 
1273 		tid->sched = false;
1274 		list_del(&tid->list);
1275 
1276 		if (ac->sched) {
1277 			ac->sched = false;
1278 			list_del(&ac->list);
1279 		}
1280 
1281 		ath_txq_unlock(sc, txq);
1282 
1283 		ieee80211_sta_set_buffered(sta, tidno, buffered);
1284 	}
1285 }
1286 
1287 void ath_tx_aggr_wakeup(struct ath_softc *sc, struct ath_node *an)
1288 {
1289 	struct ath_atx_tid *tid;
1290 	struct ath_atx_ac *ac;
1291 	struct ath_txq *txq;
1292 	int tidno;
1293 
1294 	for (tidno = 0, tid = &an->tid[tidno];
1295 	     tidno < WME_NUM_TID; tidno++, tid++) {
1296 
1297 		ac = tid->ac;
1298 		txq = ac->txq;
1299 
1300 		ath_txq_lock(sc, txq);
1301 		ac->clear_ps_filter = true;
1302 
1303 		if (!skb_queue_empty(&tid->buf_q) && !tid->paused) {
1304 			ath_tx_queue_tid(txq, tid);
1305 			ath_txq_schedule(sc, txq);
1306 		}
1307 
1308 		ath_txq_unlock_complete(sc, txq);
1309 	}
1310 }
1311 
1312 void ath_tx_aggr_resume(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid)
1313 {
1314 	struct ath_atx_tid *txtid;
1315 	struct ath_node *an;
1316 
1317 	an = (struct ath_node *)sta->drv_priv;
1318 
1319 	txtid = ATH_AN_2_TID(an, tid);
1320 	txtid->baw_size = IEEE80211_MIN_AMPDU_BUF << sta->ht_cap.ampdu_factor;
1321 	txtid->state |= AGGR_ADDBA_COMPLETE;
1322 	txtid->state &= ~AGGR_ADDBA_PROGRESS;
1323 	ath_tx_resume_tid(sc, txtid);
1324 }
1325 
1326 /********************/
1327 /* Queue Management */
1328 /********************/
1329 
1330 static void ath_txq_drain_pending_buffers(struct ath_softc *sc,
1331 					  struct ath_txq *txq)
1332 {
1333 	struct ath_atx_ac *ac, *ac_tmp;
1334 	struct ath_atx_tid *tid, *tid_tmp;
1335 
1336 	list_for_each_entry_safe(ac, ac_tmp, &txq->axq_acq, list) {
1337 		list_del(&ac->list);
1338 		ac->sched = false;
1339 		list_for_each_entry_safe(tid, tid_tmp, &ac->tid_q, list) {
1340 			list_del(&tid->list);
1341 			tid->sched = false;
1342 			ath_tid_drain(sc, txq, tid);
1343 		}
1344 	}
1345 }
1346 
1347 struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype)
1348 {
1349 	struct ath_hw *ah = sc->sc_ah;
1350 	struct ath9k_tx_queue_info qi;
1351 	static const int subtype_txq_to_hwq[] = {
1352 		[WME_AC_BE] = ATH_TXQ_AC_BE,
1353 		[WME_AC_BK] = ATH_TXQ_AC_BK,
1354 		[WME_AC_VI] = ATH_TXQ_AC_VI,
1355 		[WME_AC_VO] = ATH_TXQ_AC_VO,
1356 	};
1357 	int axq_qnum, i;
1358 
1359 	memset(&qi, 0, sizeof(qi));
1360 	qi.tqi_subtype = subtype_txq_to_hwq[subtype];
1361 	qi.tqi_aifs = ATH9K_TXQ_USEDEFAULT;
1362 	qi.tqi_cwmin = ATH9K_TXQ_USEDEFAULT;
1363 	qi.tqi_cwmax = ATH9K_TXQ_USEDEFAULT;
1364 	qi.tqi_physCompBuf = 0;
1365 
1366 	/*
1367 	 * Enable interrupts only for EOL and DESC conditions.
1368 	 * We mark tx descriptors to receive a DESC interrupt
1369 	 * when a tx queue gets deep; otherwise waiting for the
1370 	 * EOL to reap descriptors.  Note that this is done to
1371 	 * reduce interrupt load and this only defers reaping
1372 	 * descriptors, never transmitting frames.  Aside from
1373 	 * reducing interrupts this also permits more concurrency.
1374 	 * The only potential downside is if the tx queue backs
1375 	 * up in which case the top half of the kernel may backup
1376 	 * due to a lack of tx descriptors.
1377 	 *
1378 	 * The UAPSD queue is an exception, since we take a desc-
1379 	 * based intr on the EOSP frames.
1380 	 */
1381 	if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
1382 		qi.tqi_qflags = TXQ_FLAG_TXINT_ENABLE;
1383 	} else {
1384 		if (qtype == ATH9K_TX_QUEUE_UAPSD)
1385 			qi.tqi_qflags = TXQ_FLAG_TXDESCINT_ENABLE;
1386 		else
1387 			qi.tqi_qflags = TXQ_FLAG_TXEOLINT_ENABLE |
1388 					TXQ_FLAG_TXDESCINT_ENABLE;
1389 	}
1390 	axq_qnum = ath9k_hw_setuptxqueue(ah, qtype, &qi);
1391 	if (axq_qnum == -1) {
1392 		/*
1393 		 * NB: don't print a message, this happens
1394 		 * normally on parts with too few tx queues
1395 		 */
1396 		return NULL;
1397 	}
1398 	if (!ATH_TXQ_SETUP(sc, axq_qnum)) {
1399 		struct ath_txq *txq = &sc->tx.txq[axq_qnum];
1400 
1401 		txq->axq_qnum = axq_qnum;
1402 		txq->mac80211_qnum = -1;
1403 		txq->axq_link = NULL;
1404 		__skb_queue_head_init(&txq->complete_q);
1405 		INIT_LIST_HEAD(&txq->axq_q);
1406 		INIT_LIST_HEAD(&txq->axq_acq);
1407 		spin_lock_init(&txq->axq_lock);
1408 		txq->axq_depth = 0;
1409 		txq->axq_ampdu_depth = 0;
1410 		txq->axq_tx_inprogress = false;
1411 		sc->tx.txqsetup |= 1<<axq_qnum;
1412 
1413 		txq->txq_headidx = txq->txq_tailidx = 0;
1414 		for (i = 0; i < ATH_TXFIFO_DEPTH; i++)
1415 			INIT_LIST_HEAD(&txq->txq_fifo[i]);
1416 	}
1417 	return &sc->tx.txq[axq_qnum];
1418 }
1419 
1420 int ath_txq_update(struct ath_softc *sc, int qnum,
1421 		   struct ath9k_tx_queue_info *qinfo)
1422 {
1423 	struct ath_hw *ah = sc->sc_ah;
1424 	int error = 0;
1425 	struct ath9k_tx_queue_info qi;
1426 
1427 	BUG_ON(sc->tx.txq[qnum].axq_qnum != qnum);
1428 
1429 	ath9k_hw_get_txq_props(ah, qnum, &qi);
1430 	qi.tqi_aifs = qinfo->tqi_aifs;
1431 	qi.tqi_cwmin = qinfo->tqi_cwmin;
1432 	qi.tqi_cwmax = qinfo->tqi_cwmax;
1433 	qi.tqi_burstTime = qinfo->tqi_burstTime;
1434 	qi.tqi_readyTime = qinfo->tqi_readyTime;
1435 
1436 	if (!ath9k_hw_set_txq_props(ah, qnum, &qi)) {
1437 		ath_err(ath9k_hw_common(sc->sc_ah),
1438 			"Unable to update hardware queue %u!\n", qnum);
1439 		error = -EIO;
1440 	} else {
1441 		ath9k_hw_resettxqueue(ah, qnum);
1442 	}
1443 
1444 	return error;
1445 }
1446 
1447 int ath_cabq_update(struct ath_softc *sc)
1448 {
1449 	struct ath9k_tx_queue_info qi;
1450 	struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
1451 	int qnum = sc->beacon.cabq->axq_qnum;
1452 
1453 	ath9k_hw_get_txq_props(sc->sc_ah, qnum, &qi);
1454 	/*
1455 	 * Ensure the readytime % is within the bounds.
1456 	 */
1457 	if (sc->config.cabqReadytime < ATH9K_READY_TIME_LO_BOUND)
1458 		sc->config.cabqReadytime = ATH9K_READY_TIME_LO_BOUND;
1459 	else if (sc->config.cabqReadytime > ATH9K_READY_TIME_HI_BOUND)
1460 		sc->config.cabqReadytime = ATH9K_READY_TIME_HI_BOUND;
1461 
1462 	qi.tqi_readyTime = (cur_conf->beacon_interval *
1463 			    sc->config.cabqReadytime) / 100;
1464 	ath_txq_update(sc, qnum, &qi);
1465 
1466 	return 0;
1467 }
1468 
1469 static bool bf_is_ampdu_not_probing(struct ath_buf *bf)
1470 {
1471     struct ieee80211_tx_info *info = IEEE80211_SKB_CB(bf->bf_mpdu);
1472     return bf_isampdu(bf) && !(info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE);
1473 }
1474 
1475 static void ath_drain_txq_list(struct ath_softc *sc, struct ath_txq *txq,
1476 			       struct list_head *list, bool retry_tx)
1477 {
1478 	struct ath_buf *bf, *lastbf;
1479 	struct list_head bf_head;
1480 	struct ath_tx_status ts;
1481 
1482 	memset(&ts, 0, sizeof(ts));
1483 	ts.ts_status = ATH9K_TX_FLUSH;
1484 	INIT_LIST_HEAD(&bf_head);
1485 
1486 	while (!list_empty(list)) {
1487 		bf = list_first_entry(list, struct ath_buf, list);
1488 
1489 		if (bf->bf_stale) {
1490 			list_del(&bf->list);
1491 
1492 			ath_tx_return_buffer(sc, bf);
1493 			continue;
1494 		}
1495 
1496 		lastbf = bf->bf_lastbf;
1497 		list_cut_position(&bf_head, list, &lastbf->list);
1498 
1499 		txq->axq_depth--;
1500 		if (bf_is_ampdu_not_probing(bf))
1501 			txq->axq_ampdu_depth--;
1502 
1503 		if (bf_isampdu(bf))
1504 			ath_tx_complete_aggr(sc, txq, bf, &bf_head, &ts, 0,
1505 					     retry_tx);
1506 		else
1507 			ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0);
1508 	}
1509 }
1510 
1511 /*
1512  * Drain a given TX queue (could be Beacon or Data)
1513  *
1514  * This assumes output has been stopped and
1515  * we do not need to block ath_tx_tasklet.
1516  */
1517 void ath_draintxq(struct ath_softc *sc, struct ath_txq *txq, bool retry_tx)
1518 {
1519 	ath_txq_lock(sc, txq);
1520 
1521 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
1522 		int idx = txq->txq_tailidx;
1523 
1524 		while (!list_empty(&txq->txq_fifo[idx])) {
1525 			ath_drain_txq_list(sc, txq, &txq->txq_fifo[idx],
1526 					   retry_tx);
1527 
1528 			INCR(idx, ATH_TXFIFO_DEPTH);
1529 		}
1530 		txq->txq_tailidx = idx;
1531 	}
1532 
1533 	txq->axq_link = NULL;
1534 	txq->axq_tx_inprogress = false;
1535 	ath_drain_txq_list(sc, txq, &txq->axq_q, retry_tx);
1536 
1537 	/* flush any pending frames if aggregation is enabled */
1538 	if ((sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_HT) && !retry_tx)
1539 		ath_txq_drain_pending_buffers(sc, txq);
1540 
1541 	ath_txq_unlock_complete(sc, txq);
1542 }
1543 
1544 bool ath_drain_all_txq(struct ath_softc *sc, bool retry_tx)
1545 {
1546 	struct ath_hw *ah = sc->sc_ah;
1547 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1548 	struct ath_txq *txq;
1549 	int i;
1550 	u32 npend = 0;
1551 
1552 	if (test_bit(SC_OP_INVALID, &sc->sc_flags))
1553 		return true;
1554 
1555 	ath9k_hw_abort_tx_dma(ah);
1556 
1557 	/* Check if any queue remains active */
1558 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
1559 		if (!ATH_TXQ_SETUP(sc, i))
1560 			continue;
1561 
1562 		if (ath9k_hw_numtxpending(ah, sc->tx.txq[i].axq_qnum))
1563 			npend |= BIT(i);
1564 	}
1565 
1566 	if (npend)
1567 		ath_err(common, "Failed to stop TX DMA, queues=0x%03x!\n", npend);
1568 
1569 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
1570 		if (!ATH_TXQ_SETUP(sc, i))
1571 			continue;
1572 
1573 		/*
1574 		 * The caller will resume queues with ieee80211_wake_queues.
1575 		 * Mark the queue as not stopped to prevent ath_tx_complete
1576 		 * from waking the queue too early.
1577 		 */
1578 		txq = &sc->tx.txq[i];
1579 		txq->stopped = false;
1580 		ath_draintxq(sc, txq, retry_tx);
1581 	}
1582 
1583 	return !npend;
1584 }
1585 
1586 void ath_tx_cleanupq(struct ath_softc *sc, struct ath_txq *txq)
1587 {
1588 	ath9k_hw_releasetxqueue(sc->sc_ah, txq->axq_qnum);
1589 	sc->tx.txqsetup &= ~(1<<txq->axq_qnum);
1590 }
1591 
1592 /* For each axq_acq entry, for each tid, try to schedule packets
1593  * for transmit until ampdu_depth has reached min Q depth.
1594  */
1595 void ath_txq_schedule(struct ath_softc *sc, struct ath_txq *txq)
1596 {
1597 	struct ath_atx_ac *ac, *ac_tmp, *last_ac;
1598 	struct ath_atx_tid *tid, *last_tid;
1599 
1600 	if (test_bit(SC_OP_HW_RESET, &sc->sc_flags) ||
1601 	    list_empty(&txq->axq_acq) ||
1602 	    txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH)
1603 		return;
1604 
1605 	ac = list_first_entry(&txq->axq_acq, struct ath_atx_ac, list);
1606 	last_ac = list_entry(txq->axq_acq.prev, struct ath_atx_ac, list);
1607 
1608 	list_for_each_entry_safe(ac, ac_tmp, &txq->axq_acq, list) {
1609 		last_tid = list_entry(ac->tid_q.prev, struct ath_atx_tid, list);
1610 		list_del(&ac->list);
1611 		ac->sched = false;
1612 
1613 		while (!list_empty(&ac->tid_q)) {
1614 			tid = list_first_entry(&ac->tid_q, struct ath_atx_tid,
1615 					       list);
1616 			list_del(&tid->list);
1617 			tid->sched = false;
1618 
1619 			if (tid->paused)
1620 				continue;
1621 
1622 			ath_tx_sched_aggr(sc, txq, tid);
1623 
1624 			/*
1625 			 * add tid to round-robin queue if more frames
1626 			 * are pending for the tid
1627 			 */
1628 			if (!skb_queue_empty(&tid->buf_q))
1629 				ath_tx_queue_tid(txq, tid);
1630 
1631 			if (tid == last_tid ||
1632 			    txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH)
1633 				break;
1634 		}
1635 
1636 		if (!list_empty(&ac->tid_q) && !ac->sched) {
1637 			ac->sched = true;
1638 			list_add_tail(&ac->list, &txq->axq_acq);
1639 		}
1640 
1641 		if (ac == last_ac ||
1642 		    txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH)
1643 			return;
1644 	}
1645 }
1646 
1647 /***********/
1648 /* TX, DMA */
1649 /***********/
1650 
1651 /*
1652  * Insert a chain of ath_buf (descriptors) on a txq and
1653  * assume the descriptors are already chained together by caller.
1654  */
1655 static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq,
1656 			     struct list_head *head, bool internal)
1657 {
1658 	struct ath_hw *ah = sc->sc_ah;
1659 	struct ath_common *common = ath9k_hw_common(ah);
1660 	struct ath_buf *bf, *bf_last;
1661 	bool puttxbuf = false;
1662 	bool edma;
1663 
1664 	/*
1665 	 * Insert the frame on the outbound list and
1666 	 * pass it on to the hardware.
1667 	 */
1668 
1669 	if (list_empty(head))
1670 		return;
1671 
1672 	edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
1673 	bf = list_first_entry(head, struct ath_buf, list);
1674 	bf_last = list_entry(head->prev, struct ath_buf, list);
1675 
1676 	ath_dbg(common, QUEUE, "qnum: %d, txq depth: %d\n",
1677 		txq->axq_qnum, txq->axq_depth);
1678 
1679 	if (edma && list_empty(&txq->txq_fifo[txq->txq_headidx])) {
1680 		list_splice_tail_init(head, &txq->txq_fifo[txq->txq_headidx]);
1681 		INCR(txq->txq_headidx, ATH_TXFIFO_DEPTH);
1682 		puttxbuf = true;
1683 	} else {
1684 		list_splice_tail_init(head, &txq->axq_q);
1685 
1686 		if (txq->axq_link) {
1687 			ath9k_hw_set_desc_link(ah, txq->axq_link, bf->bf_daddr);
1688 			ath_dbg(common, XMIT, "link[%u] (%p)=%llx (%p)\n",
1689 				txq->axq_qnum, txq->axq_link,
1690 				ito64(bf->bf_daddr), bf->bf_desc);
1691 		} else if (!edma)
1692 			puttxbuf = true;
1693 
1694 		txq->axq_link = bf_last->bf_desc;
1695 	}
1696 
1697 	if (puttxbuf) {
1698 		TX_STAT_INC(txq->axq_qnum, puttxbuf);
1699 		ath9k_hw_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
1700 		ath_dbg(common, XMIT, "TXDP[%u] = %llx (%p)\n",
1701 			txq->axq_qnum, ito64(bf->bf_daddr), bf->bf_desc);
1702 	}
1703 
1704 	if (!edma) {
1705 		TX_STAT_INC(txq->axq_qnum, txstart);
1706 		ath9k_hw_txstart(ah, txq->axq_qnum);
1707 	}
1708 
1709 	if (!internal) {
1710 		txq->axq_depth++;
1711 		if (bf_is_ampdu_not_probing(bf))
1712 			txq->axq_ampdu_depth++;
1713 	}
1714 }
1715 
1716 static void ath_tx_send_ampdu(struct ath_softc *sc, struct ath_atx_tid *tid,
1717 			      struct sk_buff *skb, struct ath_tx_control *txctl)
1718 {
1719 	struct ath_frame_info *fi = get_frame_info(skb);
1720 	struct list_head bf_head;
1721 	struct ath_buf *bf;
1722 
1723 	/*
1724 	 * Do not queue to h/w when any of the following conditions is true:
1725 	 * - there are pending frames in software queue
1726 	 * - the TID is currently paused for ADDBA/BAR request
1727 	 * - seqno is not within block-ack window
1728 	 * - h/w queue depth exceeds low water mark
1729 	 */
1730 	if (!skb_queue_empty(&tid->buf_q) || tid->paused ||
1731 	    !BAW_WITHIN(tid->seq_start, tid->baw_size, tid->seq_next) ||
1732 	    txctl->txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH) {
1733 		/*
1734 		 * Add this frame to software queue for scheduling later
1735 		 * for aggregation.
1736 		 */
1737 		TX_STAT_INC(txctl->txq->axq_qnum, a_queued_sw);
1738 		__skb_queue_tail(&tid->buf_q, skb);
1739 		if (!txctl->an || !txctl->an->sleeping)
1740 			ath_tx_queue_tid(txctl->txq, tid);
1741 		return;
1742 	}
1743 
1744 	bf = ath_tx_setup_buffer(sc, txctl->txq, tid, skb);
1745 	if (!bf) {
1746 		ieee80211_free_txskb(sc->hw, skb);
1747 		return;
1748 	}
1749 
1750 	bf->bf_state.bf_type = BUF_AMPDU;
1751 	INIT_LIST_HEAD(&bf_head);
1752 	list_add(&bf->list, &bf_head);
1753 
1754 	/* Add sub-frame to BAW */
1755 	ath_tx_addto_baw(sc, tid, bf->bf_state.seqno);
1756 
1757 	/* Queue to h/w without aggregation */
1758 	TX_STAT_INC(txctl->txq->axq_qnum, a_queued_hw);
1759 	bf->bf_lastbf = bf;
1760 	ath_tx_fill_desc(sc, bf, txctl->txq, fi->framelen);
1761 	ath_tx_txqaddbuf(sc, txctl->txq, &bf_head, false);
1762 }
1763 
1764 static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
1765 			       struct ath_atx_tid *tid, struct sk_buff *skb)
1766 {
1767 	struct ath_frame_info *fi = get_frame_info(skb);
1768 	struct list_head bf_head;
1769 	struct ath_buf *bf;
1770 
1771 	bf = fi->bf;
1772 
1773 	INIT_LIST_HEAD(&bf_head);
1774 	list_add_tail(&bf->list, &bf_head);
1775 	bf->bf_state.bf_type = 0;
1776 
1777 	bf->bf_lastbf = bf;
1778 	ath_tx_fill_desc(sc, bf, txq, fi->framelen);
1779 	ath_tx_txqaddbuf(sc, txq, &bf_head, false);
1780 	TX_STAT_INC(txq->axq_qnum, queued);
1781 }
1782 
1783 static void setup_frame_info(struct ieee80211_hw *hw,
1784 			     struct ieee80211_sta *sta,
1785 			     struct sk_buff *skb,
1786 			     int framelen)
1787 {
1788 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1789 	struct ieee80211_key_conf *hw_key = tx_info->control.hw_key;
1790 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1791 	const struct ieee80211_rate *rate;
1792 	struct ath_frame_info *fi = get_frame_info(skb);
1793 	struct ath_node *an = NULL;
1794 	enum ath9k_key_type keytype;
1795 	bool short_preamble = false;
1796 
1797 	/*
1798 	 * We check if Short Preamble is needed for the CTS rate by
1799 	 * checking the BSS's global flag.
1800 	 * But for the rate series, IEEE80211_TX_RC_USE_SHORT_PREAMBLE is used.
1801 	 */
1802 	if (tx_info->control.vif &&
1803 	    tx_info->control.vif->bss_conf.use_short_preamble)
1804 		short_preamble = true;
1805 
1806 	rate = ieee80211_get_rts_cts_rate(hw, tx_info);
1807 	keytype = ath9k_cmn_get_hw_crypto_keytype(skb);
1808 
1809 	if (sta)
1810 		an = (struct ath_node *) sta->drv_priv;
1811 
1812 	memset(fi, 0, sizeof(*fi));
1813 	if (hw_key)
1814 		fi->keyix = hw_key->hw_key_idx;
1815 	else if (an && ieee80211_is_data(hdr->frame_control) && an->ps_key > 0)
1816 		fi->keyix = an->ps_key;
1817 	else
1818 		fi->keyix = ATH9K_TXKEYIX_INVALID;
1819 	fi->keytype = keytype;
1820 	fi->framelen = framelen;
1821 	fi->rtscts_rate = rate->hw_value;
1822 	if (short_preamble)
1823 		fi->rtscts_rate |= rate->hw_value_short;
1824 }
1825 
1826 u8 ath_txchainmask_reduction(struct ath_softc *sc, u8 chainmask, u32 rate)
1827 {
1828 	struct ath_hw *ah = sc->sc_ah;
1829 	struct ath9k_channel *curchan = ah->curchan;
1830 
1831 	if ((ah->caps.hw_caps & ATH9K_HW_CAP_APM) &&
1832 	    (curchan->channelFlags & CHANNEL_5GHZ) &&
1833 	    (chainmask == 0x7) && (rate < 0x90))
1834 		return 0x3;
1835 	else if (AR_SREV_9462(ah) && ath9k_hw_btcoex_is_enabled(ah) &&
1836 		 IS_CCK_RATE(rate))
1837 		return 0x2;
1838 	else
1839 		return chainmask;
1840 }
1841 
1842 /*
1843  * Assign a descriptor (and sequence number if necessary,
1844  * and map buffer for DMA. Frees skb on error
1845  */
1846 static struct ath_buf *ath_tx_setup_buffer(struct ath_softc *sc,
1847 					   struct ath_txq *txq,
1848 					   struct ath_atx_tid *tid,
1849 					   struct sk_buff *skb)
1850 {
1851 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1852 	struct ath_frame_info *fi = get_frame_info(skb);
1853 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1854 	struct ath_buf *bf;
1855 	int fragno;
1856 	u16 seqno;
1857 
1858 	bf = ath_tx_get_buffer(sc);
1859 	if (!bf) {
1860 		ath_dbg(common, XMIT, "TX buffers are full\n");
1861 		return NULL;
1862 	}
1863 
1864 	ATH_TXBUF_RESET(bf);
1865 
1866 	if (tid) {
1867 		fragno = le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG;
1868 		seqno = tid->seq_next;
1869 		hdr->seq_ctrl = cpu_to_le16(tid->seq_next << IEEE80211_SEQ_SEQ_SHIFT);
1870 
1871 		if (fragno)
1872 			hdr->seq_ctrl |= cpu_to_le16(fragno);
1873 
1874 		if (!ieee80211_has_morefrags(hdr->frame_control))
1875 			INCR(tid->seq_next, IEEE80211_SEQ_MAX);
1876 
1877 		bf->bf_state.seqno = seqno;
1878 	}
1879 
1880 	bf->bf_mpdu = skb;
1881 
1882 	bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
1883 					 skb->len, DMA_TO_DEVICE);
1884 	if (unlikely(dma_mapping_error(sc->dev, bf->bf_buf_addr))) {
1885 		bf->bf_mpdu = NULL;
1886 		bf->bf_buf_addr = 0;
1887 		ath_err(ath9k_hw_common(sc->sc_ah),
1888 			"dma_mapping_error() on TX\n");
1889 		ath_tx_return_buffer(sc, bf);
1890 		return NULL;
1891 	}
1892 
1893 	fi->bf = bf;
1894 
1895 	return bf;
1896 }
1897 
1898 /* FIXME: tx power */
1899 static void ath_tx_start_dma(struct ath_softc *sc, struct sk_buff *skb,
1900 			     struct ath_tx_control *txctl)
1901 {
1902 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1903 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1904 	struct ath_atx_tid *tid = NULL;
1905 	struct ath_buf *bf;
1906 	u8 tidno;
1907 
1908 	if ((sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_HT) && txctl->an &&
1909 		ieee80211_is_data_qos(hdr->frame_control)) {
1910 		tidno = ieee80211_get_qos_ctl(hdr)[0] &
1911 			IEEE80211_QOS_CTL_TID_MASK;
1912 		tid = ATH_AN_2_TID(txctl->an, tidno);
1913 
1914 		WARN_ON(tid->ac->txq != txctl->txq);
1915 	}
1916 
1917 	if ((tx_info->flags & IEEE80211_TX_CTL_AMPDU) && tid) {
1918 		/*
1919 		 * Try aggregation if it's a unicast data frame
1920 		 * and the destination is HT capable.
1921 		 */
1922 		ath_tx_send_ampdu(sc, tid, skb, txctl);
1923 	} else {
1924 		bf = ath_tx_setup_buffer(sc, txctl->txq, tid, skb);
1925 		if (!bf) {
1926 			if (txctl->paprd)
1927 				dev_kfree_skb_any(skb);
1928 			else
1929 				ieee80211_free_txskb(sc->hw, skb);
1930 			return;
1931 		}
1932 
1933 		bf->bf_state.bfs_paprd = txctl->paprd;
1934 
1935 		if (txctl->paprd)
1936 			bf->bf_state.bfs_paprd_timestamp = jiffies;
1937 
1938 		ath_tx_send_normal(sc, txctl->txq, tid, skb);
1939 	}
1940 }
1941 
1942 /* Upon failure caller should free skb */
1943 int ath_tx_start(struct ieee80211_hw *hw, struct sk_buff *skb,
1944 		 struct ath_tx_control *txctl)
1945 {
1946 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1947 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1948 	struct ieee80211_sta *sta = txctl->sta;
1949 	struct ieee80211_vif *vif = info->control.vif;
1950 	struct ath_softc *sc = hw->priv;
1951 	struct ath_txq *txq = txctl->txq;
1952 	int padpos, padsize;
1953 	int frmlen = skb->len + FCS_LEN;
1954 	int q;
1955 
1956 	/* NOTE:  sta can be NULL according to net/mac80211.h */
1957 	if (sta)
1958 		txctl->an = (struct ath_node *)sta->drv_priv;
1959 
1960 	if (info->control.hw_key)
1961 		frmlen += info->control.hw_key->icv_len;
1962 
1963 	/*
1964 	 * As a temporary workaround, assign seq# here; this will likely need
1965 	 * to be cleaned up to work better with Beacon transmission and virtual
1966 	 * BSSes.
1967 	 */
1968 	if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
1969 		if (info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)
1970 			sc->tx.seq_no += 0x10;
1971 		hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
1972 		hdr->seq_ctrl |= cpu_to_le16(sc->tx.seq_no);
1973 	}
1974 
1975 	/* Add the padding after the header if this is not already done */
1976 	padpos = ath9k_cmn_padpos(hdr->frame_control);
1977 	padsize = padpos & 3;
1978 	if (padsize && skb->len > padpos) {
1979 		if (skb_headroom(skb) < padsize)
1980 			return -ENOMEM;
1981 
1982 		skb_push(skb, padsize);
1983 		memmove(skb->data, skb->data + padsize, padpos);
1984 		hdr = (struct ieee80211_hdr *) skb->data;
1985 	}
1986 
1987 	if ((vif && vif->type != NL80211_IFTYPE_AP &&
1988 	            vif->type != NL80211_IFTYPE_AP_VLAN) ||
1989 	    !ieee80211_is_data(hdr->frame_control))
1990 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1991 
1992 	setup_frame_info(hw, sta, skb, frmlen);
1993 
1994 	/*
1995 	 * At this point, the vif, hw_key and sta pointers in the tx control
1996 	 * info are no longer valid (overwritten by the ath_frame_info data.
1997 	 */
1998 
1999 	q = skb_get_queue_mapping(skb);
2000 
2001 	ath_txq_lock(sc, txq);
2002 	if (txq == sc->tx.txq_map[q] &&
2003 	    ++txq->pending_frames > sc->tx.txq_max_pending[q] &&
2004 	    !txq->stopped) {
2005 		ieee80211_stop_queue(sc->hw, q);
2006 		txq->stopped = true;
2007 	}
2008 
2009 	ath_tx_start_dma(sc, skb, txctl);
2010 
2011 	ath_txq_unlock(sc, txq);
2012 
2013 	return 0;
2014 }
2015 
2016 /*****************/
2017 /* TX Completion */
2018 /*****************/
2019 
2020 static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
2021 			    int tx_flags, struct ath_txq *txq)
2022 {
2023 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
2024 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2025 	struct ieee80211_hdr * hdr = (struct ieee80211_hdr *)skb->data;
2026 	int q, padpos, padsize;
2027 	unsigned long flags;
2028 
2029 	ath_dbg(common, XMIT, "TX complete: skb: %p\n", skb);
2030 
2031 	if (sc->sc_ah->caldata)
2032 		sc->sc_ah->caldata->paprd_packet_sent = true;
2033 
2034 	if (!(tx_flags & ATH_TX_ERROR))
2035 		/* Frame was ACKed */
2036 		tx_info->flags |= IEEE80211_TX_STAT_ACK;
2037 
2038 	padpos = ath9k_cmn_padpos(hdr->frame_control);
2039 	padsize = padpos & 3;
2040 	if (padsize && skb->len>padpos+padsize) {
2041 		/*
2042 		 * Remove MAC header padding before giving the frame back to
2043 		 * mac80211.
2044 		 */
2045 		memmove(skb->data + padsize, skb->data, padpos);
2046 		skb_pull(skb, padsize);
2047 	}
2048 
2049 	spin_lock_irqsave(&sc->sc_pm_lock, flags);
2050 	if ((sc->ps_flags & PS_WAIT_FOR_TX_ACK) && !txq->axq_depth) {
2051 		sc->ps_flags &= ~PS_WAIT_FOR_TX_ACK;
2052 		ath_dbg(common, PS,
2053 			"Going back to sleep after having received TX status (0x%lx)\n",
2054 			sc->ps_flags & (PS_WAIT_FOR_BEACON |
2055 					PS_WAIT_FOR_CAB |
2056 					PS_WAIT_FOR_PSPOLL_DATA |
2057 					PS_WAIT_FOR_TX_ACK));
2058 	}
2059 	spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
2060 
2061 	q = skb_get_queue_mapping(skb);
2062 	if (txq == sc->tx.txq_map[q]) {
2063 		if (WARN_ON(--txq->pending_frames < 0))
2064 			txq->pending_frames = 0;
2065 
2066 		if (txq->stopped &&
2067 		    txq->pending_frames < sc->tx.txq_max_pending[q]) {
2068 			ieee80211_wake_queue(sc->hw, q);
2069 			txq->stopped = false;
2070 		}
2071 	}
2072 
2073 	__skb_queue_tail(&txq->complete_q, skb);
2074 }
2075 
2076 static void ath_tx_complete_buf(struct ath_softc *sc, struct ath_buf *bf,
2077 				struct ath_txq *txq, struct list_head *bf_q,
2078 				struct ath_tx_status *ts, int txok)
2079 {
2080 	struct sk_buff *skb = bf->bf_mpdu;
2081 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
2082 	unsigned long flags;
2083 	int tx_flags = 0;
2084 
2085 	if (!txok)
2086 		tx_flags |= ATH_TX_ERROR;
2087 
2088 	if (ts->ts_status & ATH9K_TXERR_FILT)
2089 		tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
2090 
2091 	dma_unmap_single(sc->dev, bf->bf_buf_addr, skb->len, DMA_TO_DEVICE);
2092 	bf->bf_buf_addr = 0;
2093 
2094 	if (bf->bf_state.bfs_paprd) {
2095 		if (time_after(jiffies,
2096 				bf->bf_state.bfs_paprd_timestamp +
2097 				msecs_to_jiffies(ATH_PAPRD_TIMEOUT)))
2098 			dev_kfree_skb_any(skb);
2099 		else
2100 			complete(&sc->paprd_complete);
2101 	} else {
2102 		ath_debug_stat_tx(sc, bf, ts, txq, tx_flags);
2103 		ath_tx_complete(sc, skb, tx_flags, txq);
2104 	}
2105 	/* At this point, skb (bf->bf_mpdu) is consumed...make sure we don't
2106 	 * accidentally reference it later.
2107 	 */
2108 	bf->bf_mpdu = NULL;
2109 
2110 	/*
2111 	 * Return the list of ath_buf of this mpdu to free queue
2112 	 */
2113 	spin_lock_irqsave(&sc->tx.txbuflock, flags);
2114 	list_splice_tail_init(bf_q, &sc->tx.txbuf);
2115 	spin_unlock_irqrestore(&sc->tx.txbuflock, flags);
2116 }
2117 
2118 static void ath_tx_rc_status(struct ath_softc *sc, struct ath_buf *bf,
2119 			     struct ath_tx_status *ts, int nframes, int nbad,
2120 			     int txok)
2121 {
2122 	struct sk_buff *skb = bf->bf_mpdu;
2123 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2124 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
2125 	struct ieee80211_hw *hw = sc->hw;
2126 	struct ath_hw *ah = sc->sc_ah;
2127 	u8 i, tx_rateindex;
2128 
2129 	if (txok)
2130 		tx_info->status.ack_signal = ts->ts_rssi;
2131 
2132 	tx_rateindex = ts->ts_rateindex;
2133 	WARN_ON(tx_rateindex >= hw->max_rates);
2134 
2135 	if (tx_info->flags & IEEE80211_TX_CTL_AMPDU) {
2136 		tx_info->flags |= IEEE80211_TX_STAT_AMPDU;
2137 
2138 		BUG_ON(nbad > nframes);
2139 	}
2140 	tx_info->status.ampdu_len = nframes;
2141 	tx_info->status.ampdu_ack_len = nframes - nbad;
2142 
2143 	if ((ts->ts_status & ATH9K_TXERR_FILT) == 0 &&
2144 	    (tx_info->flags & IEEE80211_TX_CTL_NO_ACK) == 0) {
2145 		/*
2146 		 * If an underrun error is seen assume it as an excessive
2147 		 * retry only if max frame trigger level has been reached
2148 		 * (2 KB for single stream, and 4 KB for dual stream).
2149 		 * Adjust the long retry as if the frame was tried
2150 		 * hw->max_rate_tries times to affect how rate control updates
2151 		 * PER for the failed rate.
2152 		 * In case of congestion on the bus penalizing this type of
2153 		 * underruns should help hardware actually transmit new frames
2154 		 * successfully by eventually preferring slower rates.
2155 		 * This itself should also alleviate congestion on the bus.
2156 		 */
2157 		if (unlikely(ts->ts_flags & (ATH9K_TX_DATA_UNDERRUN |
2158 		                             ATH9K_TX_DELIM_UNDERRUN)) &&
2159 		    ieee80211_is_data(hdr->frame_control) &&
2160 		    ah->tx_trig_level >= sc->sc_ah->config.max_txtrig_level)
2161 			tx_info->status.rates[tx_rateindex].count =
2162 				hw->max_rate_tries;
2163 	}
2164 
2165 	for (i = tx_rateindex + 1; i < hw->max_rates; i++) {
2166 		tx_info->status.rates[i].count = 0;
2167 		tx_info->status.rates[i].idx = -1;
2168 	}
2169 
2170 	tx_info->status.rates[tx_rateindex].count = ts->ts_longretry + 1;
2171 }
2172 
2173 static void ath_tx_process_buffer(struct ath_softc *sc, struct ath_txq *txq,
2174 				  struct ath_tx_status *ts, struct ath_buf *bf,
2175 				  struct list_head *bf_head)
2176 {
2177 	int txok;
2178 
2179 	txq->axq_depth--;
2180 	txok = !(ts->ts_status & ATH9K_TXERR_MASK);
2181 	txq->axq_tx_inprogress = false;
2182 	if (bf_is_ampdu_not_probing(bf))
2183 		txq->axq_ampdu_depth--;
2184 
2185 	if (!bf_isampdu(bf)) {
2186 		ath_tx_rc_status(sc, bf, ts, 1, txok ? 0 : 1, txok);
2187 		ath_tx_complete_buf(sc, bf, txq, bf_head, ts, txok);
2188 	} else
2189 		ath_tx_complete_aggr(sc, txq, bf, bf_head, ts, txok, true);
2190 
2191 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_HT)
2192 		ath_txq_schedule(sc, txq);
2193 }
2194 
2195 static void ath_tx_processq(struct ath_softc *sc, struct ath_txq *txq)
2196 {
2197 	struct ath_hw *ah = sc->sc_ah;
2198 	struct ath_common *common = ath9k_hw_common(ah);
2199 	struct ath_buf *bf, *lastbf, *bf_held = NULL;
2200 	struct list_head bf_head;
2201 	struct ath_desc *ds;
2202 	struct ath_tx_status ts;
2203 	int status;
2204 
2205 	ath_dbg(common, QUEUE, "tx queue %d (%x), link %p\n",
2206 		txq->axq_qnum, ath9k_hw_gettxbuf(sc->sc_ah, txq->axq_qnum),
2207 		txq->axq_link);
2208 
2209 	ath_txq_lock(sc, txq);
2210 	for (;;) {
2211 		if (test_bit(SC_OP_HW_RESET, &sc->sc_flags))
2212 			break;
2213 
2214 		if (list_empty(&txq->axq_q)) {
2215 			txq->axq_link = NULL;
2216 			if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_HT)
2217 				ath_txq_schedule(sc, txq);
2218 			break;
2219 		}
2220 		bf = list_first_entry(&txq->axq_q, struct ath_buf, list);
2221 
2222 		/*
2223 		 * There is a race condition that a BH gets scheduled
2224 		 * after sw writes TxE and before hw re-load the last
2225 		 * descriptor to get the newly chained one.
2226 		 * Software must keep the last DONE descriptor as a
2227 		 * holding descriptor - software does so by marking
2228 		 * it with the STALE flag.
2229 		 */
2230 		bf_held = NULL;
2231 		if (bf->bf_stale) {
2232 			bf_held = bf;
2233 			if (list_is_last(&bf_held->list, &txq->axq_q))
2234 				break;
2235 
2236 			bf = list_entry(bf_held->list.next, struct ath_buf,
2237 					list);
2238 		}
2239 
2240 		lastbf = bf->bf_lastbf;
2241 		ds = lastbf->bf_desc;
2242 
2243 		memset(&ts, 0, sizeof(ts));
2244 		status = ath9k_hw_txprocdesc(ah, ds, &ts);
2245 		if (status == -EINPROGRESS)
2246 			break;
2247 
2248 		TX_STAT_INC(txq->axq_qnum, txprocdesc);
2249 
2250 		/*
2251 		 * Remove ath_buf's of the same transmit unit from txq,
2252 		 * however leave the last descriptor back as the holding
2253 		 * descriptor for hw.
2254 		 */
2255 		lastbf->bf_stale = true;
2256 		INIT_LIST_HEAD(&bf_head);
2257 		if (!list_is_singular(&lastbf->list))
2258 			list_cut_position(&bf_head,
2259 				&txq->axq_q, lastbf->list.prev);
2260 
2261 		if (bf_held) {
2262 			list_del(&bf_held->list);
2263 			ath_tx_return_buffer(sc, bf_held);
2264 		}
2265 
2266 		ath_tx_process_buffer(sc, txq, &ts, bf, &bf_head);
2267 	}
2268 	ath_txq_unlock_complete(sc, txq);
2269 }
2270 
2271 void ath_tx_tasklet(struct ath_softc *sc)
2272 {
2273 	struct ath_hw *ah = sc->sc_ah;
2274 	u32 qcumask = ((1 << ATH9K_NUM_TX_QUEUES) - 1) & ah->intr_txqs;
2275 	int i;
2276 
2277 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
2278 		if (ATH_TXQ_SETUP(sc, i) && (qcumask & (1 << i)))
2279 			ath_tx_processq(sc, &sc->tx.txq[i]);
2280 	}
2281 }
2282 
2283 void ath_tx_edma_tasklet(struct ath_softc *sc)
2284 {
2285 	struct ath_tx_status ts;
2286 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2287 	struct ath_hw *ah = sc->sc_ah;
2288 	struct ath_txq *txq;
2289 	struct ath_buf *bf, *lastbf;
2290 	struct list_head bf_head;
2291 	int status;
2292 
2293 	for (;;) {
2294 		if (test_bit(SC_OP_HW_RESET, &sc->sc_flags))
2295 			break;
2296 
2297 		status = ath9k_hw_txprocdesc(ah, NULL, (void *)&ts);
2298 		if (status == -EINPROGRESS)
2299 			break;
2300 		if (status == -EIO) {
2301 			ath_dbg(common, XMIT, "Error processing tx status\n");
2302 			break;
2303 		}
2304 
2305 		/* Process beacon completions separately */
2306 		if (ts.qid == sc->beacon.beaconq) {
2307 			sc->beacon.tx_processed = true;
2308 			sc->beacon.tx_last = !(ts.ts_status & ATH9K_TXERR_MASK);
2309 			continue;
2310 		}
2311 
2312 		txq = &sc->tx.txq[ts.qid];
2313 
2314 		ath_txq_lock(sc, txq);
2315 
2316 		if (list_empty(&txq->txq_fifo[txq->txq_tailidx])) {
2317 			ath_txq_unlock(sc, txq);
2318 			return;
2319 		}
2320 
2321 		bf = list_first_entry(&txq->txq_fifo[txq->txq_tailidx],
2322 				      struct ath_buf, list);
2323 		lastbf = bf->bf_lastbf;
2324 
2325 		INIT_LIST_HEAD(&bf_head);
2326 		list_cut_position(&bf_head, &txq->txq_fifo[txq->txq_tailidx],
2327 				  &lastbf->list);
2328 
2329 		if (list_empty(&txq->txq_fifo[txq->txq_tailidx])) {
2330 			INCR(txq->txq_tailidx, ATH_TXFIFO_DEPTH);
2331 
2332 			if (!list_empty(&txq->axq_q)) {
2333 				struct list_head bf_q;
2334 
2335 				INIT_LIST_HEAD(&bf_q);
2336 				txq->axq_link = NULL;
2337 				list_splice_tail_init(&txq->axq_q, &bf_q);
2338 				ath_tx_txqaddbuf(sc, txq, &bf_q, true);
2339 			}
2340 		}
2341 
2342 		ath_tx_process_buffer(sc, txq, &ts, bf, &bf_head);
2343 		ath_txq_unlock_complete(sc, txq);
2344 	}
2345 }
2346 
2347 /*****************/
2348 /* Init, Cleanup */
2349 /*****************/
2350 
2351 static int ath_txstatus_setup(struct ath_softc *sc, int size)
2352 {
2353 	struct ath_descdma *dd = &sc->txsdma;
2354 	u8 txs_len = sc->sc_ah->caps.txs_len;
2355 
2356 	dd->dd_desc_len = size * txs_len;
2357 	dd->dd_desc = dma_alloc_coherent(sc->dev, dd->dd_desc_len,
2358 					 &dd->dd_desc_paddr, GFP_KERNEL);
2359 	if (!dd->dd_desc)
2360 		return -ENOMEM;
2361 
2362 	return 0;
2363 }
2364 
2365 static int ath_tx_edma_init(struct ath_softc *sc)
2366 {
2367 	int err;
2368 
2369 	err = ath_txstatus_setup(sc, ATH_TXSTATUS_RING_SIZE);
2370 	if (!err)
2371 		ath9k_hw_setup_statusring(sc->sc_ah, sc->txsdma.dd_desc,
2372 					  sc->txsdma.dd_desc_paddr,
2373 					  ATH_TXSTATUS_RING_SIZE);
2374 
2375 	return err;
2376 }
2377 
2378 static void ath_tx_edma_cleanup(struct ath_softc *sc)
2379 {
2380 	struct ath_descdma *dd = &sc->txsdma;
2381 
2382 	dma_free_coherent(sc->dev, dd->dd_desc_len, dd->dd_desc,
2383 			  dd->dd_desc_paddr);
2384 }
2385 
2386 int ath_tx_init(struct ath_softc *sc, int nbufs)
2387 {
2388 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2389 	int error = 0;
2390 
2391 	spin_lock_init(&sc->tx.txbuflock);
2392 
2393 	error = ath_descdma_setup(sc, &sc->tx.txdma, &sc->tx.txbuf,
2394 				  "tx", nbufs, 1, 1);
2395 	if (error != 0) {
2396 		ath_err(common,
2397 			"Failed to allocate tx descriptors: %d\n", error);
2398 		goto err;
2399 	}
2400 
2401 	error = ath_descdma_setup(sc, &sc->beacon.bdma, &sc->beacon.bbuf,
2402 				  "beacon", ATH_BCBUF, 1, 1);
2403 	if (error != 0) {
2404 		ath_err(common,
2405 			"Failed to allocate beacon descriptors: %d\n", error);
2406 		goto err;
2407 	}
2408 
2409 	INIT_DELAYED_WORK(&sc->tx_complete_work, ath_tx_complete_poll_work);
2410 
2411 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
2412 		error = ath_tx_edma_init(sc);
2413 		if (error)
2414 			goto err;
2415 	}
2416 
2417 err:
2418 	if (error != 0)
2419 		ath_tx_cleanup(sc);
2420 
2421 	return error;
2422 }
2423 
2424 void ath_tx_cleanup(struct ath_softc *sc)
2425 {
2426 	if (sc->beacon.bdma.dd_desc_len != 0)
2427 		ath_descdma_cleanup(sc, &sc->beacon.bdma, &sc->beacon.bbuf);
2428 
2429 	if (sc->tx.txdma.dd_desc_len != 0)
2430 		ath_descdma_cleanup(sc, &sc->tx.txdma, &sc->tx.txbuf);
2431 
2432 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
2433 		ath_tx_edma_cleanup(sc);
2434 }
2435 
2436 void ath_tx_node_init(struct ath_softc *sc, struct ath_node *an)
2437 {
2438 	struct ath_atx_tid *tid;
2439 	struct ath_atx_ac *ac;
2440 	int tidno, acno;
2441 
2442 	for (tidno = 0, tid = &an->tid[tidno];
2443 	     tidno < WME_NUM_TID;
2444 	     tidno++, tid++) {
2445 		tid->an        = an;
2446 		tid->tidno     = tidno;
2447 		tid->seq_start = tid->seq_next = 0;
2448 		tid->baw_size  = WME_MAX_BA;
2449 		tid->baw_head  = tid->baw_tail = 0;
2450 		tid->sched     = false;
2451 		tid->paused    = false;
2452 		tid->state &= ~AGGR_CLEANUP;
2453 		__skb_queue_head_init(&tid->buf_q);
2454 		acno = TID_TO_WME_AC(tidno);
2455 		tid->ac = &an->ac[acno];
2456 		tid->state &= ~AGGR_ADDBA_COMPLETE;
2457 		tid->state &= ~AGGR_ADDBA_PROGRESS;
2458 	}
2459 
2460 	for (acno = 0, ac = &an->ac[acno];
2461 	     acno < WME_NUM_AC; acno++, ac++) {
2462 		ac->sched    = false;
2463 		ac->txq = sc->tx.txq_map[acno];
2464 		INIT_LIST_HEAD(&ac->tid_q);
2465 	}
2466 }
2467 
2468 void ath_tx_node_cleanup(struct ath_softc *sc, struct ath_node *an)
2469 {
2470 	struct ath_atx_ac *ac;
2471 	struct ath_atx_tid *tid;
2472 	struct ath_txq *txq;
2473 	int tidno;
2474 
2475 	for (tidno = 0, tid = &an->tid[tidno];
2476 	     tidno < WME_NUM_TID; tidno++, tid++) {
2477 
2478 		ac = tid->ac;
2479 		txq = ac->txq;
2480 
2481 		ath_txq_lock(sc, txq);
2482 
2483 		if (tid->sched) {
2484 			list_del(&tid->list);
2485 			tid->sched = false;
2486 		}
2487 
2488 		if (ac->sched) {
2489 			list_del(&ac->list);
2490 			tid->ac->sched = false;
2491 		}
2492 
2493 		ath_tid_drain(sc, txq, tid);
2494 		tid->state &= ~AGGR_ADDBA_COMPLETE;
2495 		tid->state &= ~AGGR_CLEANUP;
2496 
2497 		ath_txq_unlock(sc, txq);
2498 	}
2499 }
2500