xref: /openbmc/linux/drivers/net/wireless/ath/ath9k/xmit.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
1 /*
2  * Copyright (c) 2008-2009 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 "ath9k.h"
18 #include "ar9003_mac.h"
19 
20 #define BITS_PER_BYTE           8
21 #define OFDM_PLCP_BITS          22
22 #define HT_RC_2_MCS(_rc)        ((_rc) & 0x1f)
23 #define HT_RC_2_STREAMS(_rc)    ((((_rc) & 0x78) >> 3) + 1)
24 #define L_STF                   8
25 #define L_LTF                   8
26 #define L_SIG                   4
27 #define HT_SIG                  8
28 #define HT_STF                  4
29 #define HT_LTF(_ns)             (4 * (_ns))
30 #define SYMBOL_TIME(_ns)        ((_ns) << 2) /* ns * 4 us */
31 #define SYMBOL_TIME_HALFGI(_ns) (((_ns) * 18 + 4) / 5)  /* ns * 3.6 us */
32 #define NUM_SYMBOLS_PER_USEC(_usec) (_usec >> 2)
33 #define NUM_SYMBOLS_PER_USEC_HALFGI(_usec) (((_usec*5)-4)/18)
34 
35 #define OFDM_SIFS_TIME    	    16
36 
37 static u16 bits_per_symbol[][2] = {
38 	/* 20MHz 40MHz */
39 	{    26,   54 },     /*  0: BPSK */
40 	{    52,  108 },     /*  1: QPSK 1/2 */
41 	{    78,  162 },     /*  2: QPSK 3/4 */
42 	{   104,  216 },     /*  3: 16-QAM 1/2 */
43 	{   156,  324 },     /*  4: 16-QAM 3/4 */
44 	{   208,  432 },     /*  5: 64-QAM 2/3 */
45 	{   234,  486 },     /*  6: 64-QAM 3/4 */
46 	{   260,  540 },     /*  7: 64-QAM 5/6 */
47 };
48 
49 #define IS_HT_RATE(_rate)     ((_rate) & 0x80)
50 
51 static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
52 			       struct ath_atx_tid *tid,
53 			       struct list_head *bf_head);
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, int sendbar);
57 static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq,
58 			     struct list_head *head);
59 static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf, int len);
60 static void ath_tx_rc_status(struct ath_buf *bf, struct ath_tx_status *ts,
61 			     int nframes, int nbad, int txok, bool update_rc);
62 static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
63 			      int seqno);
64 
65 enum {
66 	MCS_HT20,
67 	MCS_HT20_SGI,
68 	MCS_HT40,
69 	MCS_HT40_SGI,
70 };
71 
72 static int ath_max_4ms_framelen[4][32] = {
73 	[MCS_HT20] = {
74 		3212,  6432,  9648,  12864,  19300,  25736,  28952,  32172,
75 		6424,  12852, 19280, 25708,  38568,  51424,  57852,  64280,
76 		9628,  19260, 28896, 38528,  57792,  65532,  65532,  65532,
77 		12828, 25656, 38488, 51320,  65532,  65532,  65532,  65532,
78 	},
79 	[MCS_HT20_SGI] = {
80 		3572,  7144,  10720,  14296,  21444,  28596,  32172,  35744,
81 		7140,  14284, 21428,  28568,  42856,  57144,  64288,  65532,
82 		10700, 21408, 32112,  42816,  64228,  65532,  65532,  65532,
83 		14256, 28516, 42780,  57040,  65532,  65532,  65532,  65532,
84 	},
85 	[MCS_HT40] = {
86 		6680,  13360,  20044,  26724,  40092,  53456,  60140,  65532,
87 		13348, 26700,  40052,  53400,  65532,  65532,  65532,  65532,
88 		20004, 40008,  60016,  65532,  65532,  65532,  65532,  65532,
89 		26644, 53292,  65532,  65532,  65532,  65532,  65532,  65532,
90 	},
91 	[MCS_HT40_SGI] = {
92 		7420,  14844,  22272,  29696,  44544,  59396,  65532,  65532,
93 		14832, 29668,  44504,  59340,  65532,  65532,  65532,  65532,
94 		22232, 44464,  65532,  65532,  65532,  65532,  65532,  65532,
95 		29616, 59232,  65532,  65532,  65532,  65532,  65532,  65532,
96 	}
97 };
98 
99 /*********************/
100 /* Aggregation logic */
101 /*********************/
102 
103 static void ath_tx_queue_tid(struct ath_txq *txq, struct ath_atx_tid *tid)
104 {
105 	struct ath_atx_ac *ac = tid->ac;
106 
107 	if (tid->paused)
108 		return;
109 
110 	if (tid->sched)
111 		return;
112 
113 	tid->sched = true;
114 	list_add_tail(&tid->list, &ac->tid_q);
115 
116 	if (ac->sched)
117 		return;
118 
119 	ac->sched = true;
120 	list_add_tail(&ac->list, &txq->axq_acq);
121 }
122 
123 static void ath_tx_resume_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
124 {
125 	struct ath_txq *txq = tid->ac->txq;
126 
127 	WARN_ON(!tid->paused);
128 
129 	spin_lock_bh(&txq->axq_lock);
130 	tid->paused = false;
131 
132 	if (list_empty(&tid->buf_q))
133 		goto unlock;
134 
135 	ath_tx_queue_tid(txq, tid);
136 	ath_txq_schedule(sc, txq);
137 unlock:
138 	spin_unlock_bh(&txq->axq_lock);
139 }
140 
141 static struct ath_frame_info *get_frame_info(struct sk_buff *skb)
142 {
143 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
144 	BUILD_BUG_ON(sizeof(struct ath_frame_info) >
145 		     sizeof(tx_info->rate_driver_data));
146 	return (struct ath_frame_info *) &tx_info->rate_driver_data[0];
147 }
148 
149 static void ath_tx_flush_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
150 {
151 	struct ath_txq *txq = tid->ac->txq;
152 	struct ath_buf *bf;
153 	struct list_head bf_head;
154 	struct ath_tx_status ts;
155 	struct ath_frame_info *fi;
156 
157 	INIT_LIST_HEAD(&bf_head);
158 
159 	memset(&ts, 0, sizeof(ts));
160 	spin_lock_bh(&txq->axq_lock);
161 
162 	while (!list_empty(&tid->buf_q)) {
163 		bf = list_first_entry(&tid->buf_q, struct ath_buf, list);
164 		list_move_tail(&bf->list, &bf_head);
165 
166 		spin_unlock_bh(&txq->axq_lock);
167 		fi = get_frame_info(bf->bf_mpdu);
168 		if (fi->retries) {
169 			ath_tx_update_baw(sc, tid, fi->seqno);
170 			ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0, 0);
171 		} else {
172 			ath_tx_send_normal(sc, txq, tid, &bf_head);
173 		}
174 		spin_lock_bh(&txq->axq_lock);
175 	}
176 
177 	spin_unlock_bh(&txq->axq_lock);
178 }
179 
180 static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
181 			      int seqno)
182 {
183 	int index, cindex;
184 
185 	index  = ATH_BA_INDEX(tid->seq_start, seqno);
186 	cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
187 
188 	__clear_bit(cindex, tid->tx_buf);
189 
190 	while (tid->baw_head != tid->baw_tail && !test_bit(tid->baw_head, tid->tx_buf)) {
191 		INCR(tid->seq_start, IEEE80211_SEQ_MAX);
192 		INCR(tid->baw_head, ATH_TID_MAX_BUFS);
193 	}
194 }
195 
196 static void ath_tx_addto_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
197 			     u16 seqno)
198 {
199 	int index, cindex;
200 
201 	index  = ATH_BA_INDEX(tid->seq_start, seqno);
202 	cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
203 	__set_bit(cindex, tid->tx_buf);
204 
205 	if (index >= ((tid->baw_tail - tid->baw_head) &
206 		(ATH_TID_MAX_BUFS - 1))) {
207 		tid->baw_tail = cindex;
208 		INCR(tid->baw_tail, ATH_TID_MAX_BUFS);
209 	}
210 }
211 
212 /*
213  * TODO: For frame(s) that are in the retry state, we will reuse the
214  * sequence number(s) without setting the retry bit. The
215  * alternative is to give up on these and BAR the receiver's window
216  * forward.
217  */
218 static void ath_tid_drain(struct ath_softc *sc, struct ath_txq *txq,
219 			  struct ath_atx_tid *tid)
220 
221 {
222 	struct ath_buf *bf;
223 	struct list_head bf_head;
224 	struct ath_tx_status ts;
225 	struct ath_frame_info *fi;
226 
227 	memset(&ts, 0, sizeof(ts));
228 	INIT_LIST_HEAD(&bf_head);
229 
230 	for (;;) {
231 		if (list_empty(&tid->buf_q))
232 			break;
233 
234 		bf = list_first_entry(&tid->buf_q, struct ath_buf, list);
235 		list_move_tail(&bf->list, &bf_head);
236 
237 		fi = get_frame_info(bf->bf_mpdu);
238 		if (fi->retries)
239 			ath_tx_update_baw(sc, tid, fi->seqno);
240 
241 		spin_unlock(&txq->axq_lock);
242 		ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0, 0);
243 		spin_lock(&txq->axq_lock);
244 	}
245 
246 	tid->seq_next = tid->seq_start;
247 	tid->baw_tail = tid->baw_head;
248 }
249 
250 static void ath_tx_set_retry(struct ath_softc *sc, struct ath_txq *txq,
251 			     struct sk_buff *skb)
252 {
253 	struct ath_frame_info *fi = get_frame_info(skb);
254 	struct ieee80211_hdr *hdr;
255 
256 	TX_STAT_INC(txq->axq_qnum, a_retries);
257 	if (fi->retries++ > 0)
258 		return;
259 
260 	hdr = (struct ieee80211_hdr *)skb->data;
261 	hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_RETRY);
262 }
263 
264 static struct ath_buf *ath_tx_get_buffer(struct ath_softc *sc)
265 {
266 	struct ath_buf *bf = NULL;
267 
268 	spin_lock_bh(&sc->tx.txbuflock);
269 
270 	if (unlikely(list_empty(&sc->tx.txbuf))) {
271 		spin_unlock_bh(&sc->tx.txbuflock);
272 		return NULL;
273 	}
274 
275 	bf = list_first_entry(&sc->tx.txbuf, struct ath_buf, list);
276 	list_del(&bf->list);
277 
278 	spin_unlock_bh(&sc->tx.txbuflock);
279 
280 	return bf;
281 }
282 
283 static void ath_tx_return_buffer(struct ath_softc *sc, struct ath_buf *bf)
284 {
285 	spin_lock_bh(&sc->tx.txbuflock);
286 	list_add_tail(&bf->list, &sc->tx.txbuf);
287 	spin_unlock_bh(&sc->tx.txbuflock);
288 }
289 
290 static struct ath_buf* ath_clone_txbuf(struct ath_softc *sc, struct ath_buf *bf)
291 {
292 	struct ath_buf *tbf;
293 
294 	tbf = ath_tx_get_buffer(sc);
295 	if (WARN_ON(!tbf))
296 		return NULL;
297 
298 	ATH_TXBUF_RESET(tbf);
299 
300 	tbf->aphy = bf->aphy;
301 	tbf->bf_mpdu = bf->bf_mpdu;
302 	tbf->bf_buf_addr = bf->bf_buf_addr;
303 	memcpy(tbf->bf_desc, bf->bf_desc, sc->sc_ah->caps.tx_desc_len);
304 	tbf->bf_state = bf->bf_state;
305 
306 	return tbf;
307 }
308 
309 static void ath_tx_count_frames(struct ath_softc *sc, struct ath_buf *bf,
310 			        struct ath_tx_status *ts, int txok,
311 			        int *nframes, int *nbad)
312 {
313 	struct ath_frame_info *fi;
314 	u16 seq_st = 0;
315 	u32 ba[WME_BA_BMP_SIZE >> 5];
316 	int ba_index;
317 	int isaggr = 0;
318 
319 	*nbad = 0;
320 	*nframes = 0;
321 
322 	isaggr = bf_isaggr(bf);
323 	if (isaggr) {
324 		seq_st = ts->ts_seqnum;
325 		memcpy(ba, &ts->ba_low, WME_BA_BMP_SIZE >> 3);
326 	}
327 
328 	while (bf) {
329 		fi = get_frame_info(bf->bf_mpdu);
330 		ba_index = ATH_BA_INDEX(seq_st, fi->seqno);
331 
332 		(*nframes)++;
333 		if (!txok || (isaggr && !ATH_BA_ISSET(ba, ba_index)))
334 			(*nbad)++;
335 
336 		bf = bf->bf_next;
337 	}
338 }
339 
340 
341 static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq,
342 				 struct ath_buf *bf, struct list_head *bf_q,
343 				 struct ath_tx_status *ts, int txok, bool retry)
344 {
345 	struct ath_node *an = NULL;
346 	struct sk_buff *skb;
347 	struct ieee80211_sta *sta;
348 	struct ieee80211_hw *hw;
349 	struct ieee80211_hdr *hdr;
350 	struct ieee80211_tx_info *tx_info;
351 	struct ath_atx_tid *tid = NULL;
352 	struct ath_buf *bf_next, *bf_last = bf->bf_lastbf;
353 	struct list_head bf_head, bf_pending;
354 	u16 seq_st = 0, acked_cnt = 0, txfail_cnt = 0;
355 	u32 ba[WME_BA_BMP_SIZE >> 5];
356 	int isaggr, txfail, txpending, sendbar = 0, needreset = 0, nbad = 0;
357 	bool rc_update = true;
358 	struct ieee80211_tx_rate rates[4];
359 	struct ath_frame_info *fi;
360 	int nframes;
361 	u8 tidno;
362 
363 	skb = bf->bf_mpdu;
364 	hdr = (struct ieee80211_hdr *)skb->data;
365 
366 	tx_info = IEEE80211_SKB_CB(skb);
367 	hw = bf->aphy->hw;
368 
369 	memcpy(rates, tx_info->control.rates, sizeof(rates));
370 
371 	rcu_read_lock();
372 
373 	sta = ieee80211_find_sta_by_ifaddr(hw, hdr->addr1, hdr->addr2);
374 	if (!sta) {
375 		rcu_read_unlock();
376 
377 		INIT_LIST_HEAD(&bf_head);
378 		while (bf) {
379 			bf_next = bf->bf_next;
380 
381 			bf->bf_state.bf_type |= BUF_XRETRY;
382 			if ((sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) ||
383 			    !bf->bf_stale || bf_next != NULL)
384 				list_move_tail(&bf->list, &bf_head);
385 
386 			ath_tx_rc_status(bf, ts, 1, 1, 0, false);
387 			ath_tx_complete_buf(sc, bf, txq, &bf_head, ts,
388 				0, 0);
389 
390 			bf = bf_next;
391 		}
392 		return;
393 	}
394 
395 	an = (struct ath_node *)sta->drv_priv;
396 	tidno = ieee80211_get_qos_ctl(hdr)[0] & IEEE80211_QOS_CTL_TID_MASK;
397 	tid = ATH_AN_2_TID(an, tidno);
398 
399 	/*
400 	 * The hardware occasionally sends a tx status for the wrong TID.
401 	 * In this case, the BA status cannot be considered valid and all
402 	 * subframes need to be retransmitted
403 	 */
404 	if (tidno != ts->tid)
405 		txok = false;
406 
407 	isaggr = bf_isaggr(bf);
408 	memset(ba, 0, WME_BA_BMP_SIZE >> 3);
409 
410 	if (isaggr && txok) {
411 		if (ts->ts_flags & ATH9K_TX_BA) {
412 			seq_st = ts->ts_seqnum;
413 			memcpy(ba, &ts->ba_low, WME_BA_BMP_SIZE >> 3);
414 		} else {
415 			/*
416 			 * AR5416 can become deaf/mute when BA
417 			 * issue happens. Chip needs to be reset.
418 			 * But AP code may have sychronization issues
419 			 * when perform internal reset in this routine.
420 			 * Only enable reset in STA mode for now.
421 			 */
422 			if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION)
423 				needreset = 1;
424 		}
425 	}
426 
427 	INIT_LIST_HEAD(&bf_pending);
428 	INIT_LIST_HEAD(&bf_head);
429 
430 	ath_tx_count_frames(sc, bf, ts, txok, &nframes, &nbad);
431 	while (bf) {
432 		txfail = txpending = 0;
433 		bf_next = bf->bf_next;
434 
435 		skb = bf->bf_mpdu;
436 		tx_info = IEEE80211_SKB_CB(skb);
437 		fi = get_frame_info(skb);
438 
439 		if (ATH_BA_ISSET(ba, ATH_BA_INDEX(seq_st, fi->seqno))) {
440 			/* transmit completion, subframe is
441 			 * acked by block ack */
442 			acked_cnt++;
443 		} else if (!isaggr && txok) {
444 			/* transmit completion */
445 			acked_cnt++;
446 		} else {
447 			if (!(tid->state & AGGR_CLEANUP) && retry) {
448 				if (fi->retries < ATH_MAX_SW_RETRIES) {
449 					ath_tx_set_retry(sc, txq, bf->bf_mpdu);
450 					txpending = 1;
451 				} else {
452 					bf->bf_state.bf_type |= BUF_XRETRY;
453 					txfail = 1;
454 					sendbar = 1;
455 					txfail_cnt++;
456 				}
457 			} else {
458 				/*
459 				 * cleanup in progress, just fail
460 				 * the un-acked sub-frames
461 				 */
462 				txfail = 1;
463 			}
464 		}
465 
466 		if (!(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) &&
467 		    bf_next == NULL) {
468 			/*
469 			 * Make sure the last desc is reclaimed if it
470 			 * not a holding desc.
471 			 */
472 			if (!bf_last->bf_stale)
473 				list_move_tail(&bf->list, &bf_head);
474 			else
475 				INIT_LIST_HEAD(&bf_head);
476 		} else {
477 			BUG_ON(list_empty(bf_q));
478 			list_move_tail(&bf->list, &bf_head);
479 		}
480 
481 		if (!txpending || (tid->state & AGGR_CLEANUP)) {
482 			/*
483 			 * complete the acked-ones/xretried ones; update
484 			 * block-ack window
485 			 */
486 			spin_lock_bh(&txq->axq_lock);
487 			ath_tx_update_baw(sc, tid, fi->seqno);
488 			spin_unlock_bh(&txq->axq_lock);
489 
490 			if (rc_update && (acked_cnt == 1 || txfail_cnt == 1)) {
491 				memcpy(tx_info->control.rates, rates, sizeof(rates));
492 				ath_tx_rc_status(bf, ts, nframes, nbad, txok, true);
493 				rc_update = false;
494 			} else {
495 				ath_tx_rc_status(bf, ts, nframes, nbad, txok, false);
496 			}
497 
498 			ath_tx_complete_buf(sc, bf, txq, &bf_head, ts,
499 				!txfail, sendbar);
500 		} else {
501 			/* retry the un-acked ones */
502 			if (!(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)) {
503 				if (bf->bf_next == NULL && bf_last->bf_stale) {
504 					struct ath_buf *tbf;
505 
506 					tbf = ath_clone_txbuf(sc, bf_last);
507 					/*
508 					 * Update tx baw and complete the
509 					 * frame with failed status if we
510 					 * run out of tx buf.
511 					 */
512 					if (!tbf) {
513 						spin_lock_bh(&txq->axq_lock);
514 						ath_tx_update_baw(sc, tid, fi->seqno);
515 						spin_unlock_bh(&txq->axq_lock);
516 
517 						bf->bf_state.bf_type |=
518 							BUF_XRETRY;
519 						ath_tx_rc_status(bf, ts, nframes,
520 								nbad, 0, false);
521 						ath_tx_complete_buf(sc, bf, txq,
522 								    &bf_head,
523 								    ts, 0, 0);
524 						break;
525 					}
526 
527 					ath9k_hw_cleartxdesc(sc->sc_ah,
528 							     tbf->bf_desc);
529 					list_add_tail(&tbf->list, &bf_head);
530 				} else {
531 					/*
532 					 * Clear descriptor status words for
533 					 * software retry
534 					 */
535 					ath9k_hw_cleartxdesc(sc->sc_ah,
536 							     bf->bf_desc);
537 				}
538 			}
539 
540 			/*
541 			 * Put this buffer to the temporary pending
542 			 * queue to retain ordering
543 			 */
544 			list_splice_tail_init(&bf_head, &bf_pending);
545 		}
546 
547 		bf = bf_next;
548 	}
549 
550 	/* prepend un-acked frames to the beginning of the pending frame queue */
551 	if (!list_empty(&bf_pending)) {
552 		spin_lock_bh(&txq->axq_lock);
553 		list_splice(&bf_pending, &tid->buf_q);
554 		ath_tx_queue_tid(txq, tid);
555 		spin_unlock_bh(&txq->axq_lock);
556 	}
557 
558 	if (tid->state & AGGR_CLEANUP) {
559 		ath_tx_flush_tid(sc, tid);
560 
561 		if (tid->baw_head == tid->baw_tail) {
562 			tid->state &= ~AGGR_ADDBA_COMPLETE;
563 			tid->state &= ~AGGR_CLEANUP;
564 		}
565 	}
566 
567 	rcu_read_unlock();
568 
569 	if (needreset)
570 		ath_reset(sc, false);
571 }
572 
573 static u32 ath_lookup_rate(struct ath_softc *sc, struct ath_buf *bf,
574 			   struct ath_atx_tid *tid)
575 {
576 	struct sk_buff *skb;
577 	struct ieee80211_tx_info *tx_info;
578 	struct ieee80211_tx_rate *rates;
579 	u32 max_4ms_framelen, frmlen;
580 	u16 aggr_limit, legacy = 0;
581 	int i;
582 
583 	skb = bf->bf_mpdu;
584 	tx_info = IEEE80211_SKB_CB(skb);
585 	rates = tx_info->control.rates;
586 
587 	/*
588 	 * Find the lowest frame length among the rate series that will have a
589 	 * 4ms transmit duration.
590 	 * TODO - TXOP limit needs to be considered.
591 	 */
592 	max_4ms_framelen = ATH_AMPDU_LIMIT_MAX;
593 
594 	for (i = 0; i < 4; i++) {
595 		if (rates[i].count) {
596 			int modeidx;
597 			if (!(rates[i].flags & IEEE80211_TX_RC_MCS)) {
598 				legacy = 1;
599 				break;
600 			}
601 
602 			if (rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
603 				modeidx = MCS_HT40;
604 			else
605 				modeidx = MCS_HT20;
606 
607 			if (rates[i].flags & IEEE80211_TX_RC_SHORT_GI)
608 				modeidx++;
609 
610 			frmlen = ath_max_4ms_framelen[modeidx][rates[i].idx];
611 			max_4ms_framelen = min(max_4ms_framelen, frmlen);
612 		}
613 	}
614 
615 	/*
616 	 * limit aggregate size by the minimum rate if rate selected is
617 	 * not a probe rate, if rate selected is a probe rate then
618 	 * avoid aggregation of this packet.
619 	 */
620 	if (tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE || legacy)
621 		return 0;
622 
623 	if (sc->sc_flags & SC_OP_BT_PRIORITY_DETECTED)
624 		aggr_limit = min((max_4ms_framelen * 3) / 8,
625 				 (u32)ATH_AMPDU_LIMIT_MAX);
626 	else
627 		aggr_limit = min(max_4ms_framelen,
628 				 (u32)ATH_AMPDU_LIMIT_MAX);
629 
630 	/*
631 	 * h/w can accept aggregates upto 16 bit lengths (65535).
632 	 * The IE, however can hold upto 65536, which shows up here
633 	 * as zero. Ignore 65536 since we  are constrained by hw.
634 	 */
635 	if (tid->an->maxampdu)
636 		aggr_limit = min(aggr_limit, tid->an->maxampdu);
637 
638 	return aggr_limit;
639 }
640 
641 /*
642  * Returns the number of delimiters to be added to
643  * meet the minimum required mpdudensity.
644  */
645 static int ath_compute_num_delims(struct ath_softc *sc, struct ath_atx_tid *tid,
646 				  struct ath_buf *bf, u16 frmlen)
647 {
648 	struct sk_buff *skb = bf->bf_mpdu;
649 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
650 	u32 nsymbits, nsymbols;
651 	u16 minlen;
652 	u8 flags, rix;
653 	int width, streams, half_gi, ndelim, mindelim;
654 	struct ath_frame_info *fi = get_frame_info(bf->bf_mpdu);
655 
656 	/* Select standard number of delimiters based on frame length alone */
657 	ndelim = ATH_AGGR_GET_NDELIM(frmlen);
658 
659 	/*
660 	 * If encryption enabled, hardware requires some more padding between
661 	 * subframes.
662 	 * TODO - this could be improved to be dependent on the rate.
663 	 *      The hardware can keep up at lower rates, but not higher rates
664 	 */
665 	if (fi->keyix != ATH9K_TXKEYIX_INVALID)
666 		ndelim += ATH_AGGR_ENCRYPTDELIM;
667 
668 	/*
669 	 * Convert desired mpdu density from microeconds to bytes based
670 	 * on highest rate in rate series (i.e. first rate) to determine
671 	 * required minimum length for subframe. Take into account
672 	 * whether high rate is 20 or 40Mhz and half or full GI.
673 	 *
674 	 * If there is no mpdu density restriction, no further calculation
675 	 * is needed.
676 	 */
677 
678 	if (tid->an->mpdudensity == 0)
679 		return ndelim;
680 
681 	rix = tx_info->control.rates[0].idx;
682 	flags = tx_info->control.rates[0].flags;
683 	width = (flags & IEEE80211_TX_RC_40_MHZ_WIDTH) ? 1 : 0;
684 	half_gi = (flags & IEEE80211_TX_RC_SHORT_GI) ? 1 : 0;
685 
686 	if (half_gi)
687 		nsymbols = NUM_SYMBOLS_PER_USEC_HALFGI(tid->an->mpdudensity);
688 	else
689 		nsymbols = NUM_SYMBOLS_PER_USEC(tid->an->mpdudensity);
690 
691 	if (nsymbols == 0)
692 		nsymbols = 1;
693 
694 	streams = HT_RC_2_STREAMS(rix);
695 	nsymbits = bits_per_symbol[rix % 8][width] * streams;
696 	minlen = (nsymbols * nsymbits) / BITS_PER_BYTE;
697 
698 	if (frmlen < minlen) {
699 		mindelim = (minlen - frmlen) / ATH_AGGR_DELIM_SZ;
700 		ndelim = max(mindelim, ndelim);
701 	}
702 
703 	return ndelim;
704 }
705 
706 static enum ATH_AGGR_STATUS ath_tx_form_aggr(struct ath_softc *sc,
707 					     struct ath_txq *txq,
708 					     struct ath_atx_tid *tid,
709 					     struct list_head *bf_q,
710 					     int *aggr_len)
711 {
712 #define PADBYTES(_len) ((4 - ((_len) % 4)) % 4)
713 	struct ath_buf *bf, *bf_first, *bf_prev = NULL;
714 	int rl = 0, nframes = 0, ndelim, prev_al = 0;
715 	u16 aggr_limit = 0, al = 0, bpad = 0,
716 		al_delta, h_baw = tid->baw_size / 2;
717 	enum ATH_AGGR_STATUS status = ATH_AGGR_DONE;
718 	struct ieee80211_tx_info *tx_info;
719 	struct ath_frame_info *fi;
720 
721 	bf_first = list_first_entry(&tid->buf_q, struct ath_buf, list);
722 
723 	do {
724 		bf = list_first_entry(&tid->buf_q, struct ath_buf, list);
725 		fi = get_frame_info(bf->bf_mpdu);
726 
727 		/* do not step over block-ack window */
728 		if (!BAW_WITHIN(tid->seq_start, tid->baw_size, fi->seqno)) {
729 			status = ATH_AGGR_BAW_CLOSED;
730 			break;
731 		}
732 
733 		if (!rl) {
734 			aggr_limit = ath_lookup_rate(sc, bf, tid);
735 			rl = 1;
736 		}
737 
738 		/* do not exceed aggregation limit */
739 		al_delta = ATH_AGGR_DELIM_SZ + fi->framelen;
740 
741 		if (nframes &&
742 		    (aggr_limit < (al + bpad + al_delta + prev_al))) {
743 			status = ATH_AGGR_LIMITED;
744 			break;
745 		}
746 
747 		tx_info = IEEE80211_SKB_CB(bf->bf_mpdu);
748 		if (nframes && ((tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE) ||
749 			!(tx_info->control.rates[0].flags & IEEE80211_TX_RC_MCS)))
750 			break;
751 
752 		/* do not exceed subframe limit */
753 		if (nframes >= min((int)h_baw, ATH_AMPDU_SUBFRAME_DEFAULT)) {
754 			status = ATH_AGGR_LIMITED;
755 			break;
756 		}
757 		nframes++;
758 
759 		/* add padding for previous frame to aggregation length */
760 		al += bpad + al_delta;
761 
762 		/*
763 		 * Get the delimiters needed to meet the MPDU
764 		 * density for this node.
765 		 */
766 		ndelim = ath_compute_num_delims(sc, tid, bf_first, fi->framelen);
767 		bpad = PADBYTES(al_delta) + (ndelim << 2);
768 
769 		bf->bf_next = NULL;
770 		ath9k_hw_set_desc_link(sc->sc_ah, bf->bf_desc, 0);
771 
772 		/* link buffers of this frame to the aggregate */
773 		if (!fi->retries)
774 			ath_tx_addto_baw(sc, tid, fi->seqno);
775 		ath9k_hw_set11n_aggr_middle(sc->sc_ah, bf->bf_desc, ndelim);
776 		list_move_tail(&bf->list, bf_q);
777 		if (bf_prev) {
778 			bf_prev->bf_next = bf;
779 			ath9k_hw_set_desc_link(sc->sc_ah, bf_prev->bf_desc,
780 					       bf->bf_daddr);
781 		}
782 		bf_prev = bf;
783 
784 	} while (!list_empty(&tid->buf_q));
785 
786 	*aggr_len = al;
787 
788 	return status;
789 #undef PADBYTES
790 }
791 
792 static void ath_tx_sched_aggr(struct ath_softc *sc, struct ath_txq *txq,
793 			      struct ath_atx_tid *tid)
794 {
795 	struct ath_buf *bf;
796 	enum ATH_AGGR_STATUS status;
797 	struct ath_frame_info *fi;
798 	struct list_head bf_q;
799 	int aggr_len;
800 
801 	do {
802 		if (list_empty(&tid->buf_q))
803 			return;
804 
805 		INIT_LIST_HEAD(&bf_q);
806 
807 		status = ath_tx_form_aggr(sc, txq, tid, &bf_q, &aggr_len);
808 
809 		/*
810 		 * no frames picked up to be aggregated;
811 		 * block-ack window is not open.
812 		 */
813 		if (list_empty(&bf_q))
814 			break;
815 
816 		bf = list_first_entry(&bf_q, struct ath_buf, list);
817 		bf->bf_lastbf = list_entry(bf_q.prev, struct ath_buf, list);
818 
819 		/* if only one frame, send as non-aggregate */
820 		if (bf == bf->bf_lastbf) {
821 			fi = get_frame_info(bf->bf_mpdu);
822 
823 			bf->bf_state.bf_type &= ~BUF_AGGR;
824 			ath9k_hw_clr11n_aggr(sc->sc_ah, bf->bf_desc);
825 			ath_buf_set_rate(sc, bf, fi->framelen);
826 			ath_tx_txqaddbuf(sc, txq, &bf_q);
827 			continue;
828 		}
829 
830 		/* setup first desc of aggregate */
831 		bf->bf_state.bf_type |= BUF_AGGR;
832 		ath_buf_set_rate(sc, bf, aggr_len);
833 		ath9k_hw_set11n_aggr_first(sc->sc_ah, bf->bf_desc, aggr_len);
834 
835 		/* anchor last desc of aggregate */
836 		ath9k_hw_set11n_aggr_last(sc->sc_ah, bf->bf_lastbf->bf_desc);
837 
838 		ath_tx_txqaddbuf(sc, txq, &bf_q);
839 		TX_STAT_INC(txq->axq_qnum, a_aggr);
840 
841 	} while (txq->axq_ampdu_depth < ATH_AGGR_MIN_QDEPTH &&
842 		 status != ATH_AGGR_BAW_CLOSED);
843 }
844 
845 int ath_tx_aggr_start(struct ath_softc *sc, struct ieee80211_sta *sta,
846 		      u16 tid, u16 *ssn)
847 {
848 	struct ath_atx_tid *txtid;
849 	struct ath_node *an;
850 
851 	an = (struct ath_node *)sta->drv_priv;
852 	txtid = ATH_AN_2_TID(an, tid);
853 
854 	if (txtid->state & (AGGR_CLEANUP | AGGR_ADDBA_COMPLETE))
855 		return -EAGAIN;
856 
857 	txtid->state |= AGGR_ADDBA_PROGRESS;
858 	txtid->paused = true;
859 	*ssn = txtid->seq_start;
860 
861 	return 0;
862 }
863 
864 void ath_tx_aggr_stop(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid)
865 {
866 	struct ath_node *an = (struct ath_node *)sta->drv_priv;
867 	struct ath_atx_tid *txtid = ATH_AN_2_TID(an, tid);
868 	struct ath_txq *txq = txtid->ac->txq;
869 
870 	if (txtid->state & AGGR_CLEANUP)
871 		return;
872 
873 	if (!(txtid->state & AGGR_ADDBA_COMPLETE)) {
874 		txtid->state &= ~AGGR_ADDBA_PROGRESS;
875 		return;
876 	}
877 
878 	spin_lock_bh(&txq->axq_lock);
879 	txtid->paused = true;
880 
881 	/*
882 	 * If frames are still being transmitted for this TID, they will be
883 	 * cleaned up during tx completion. To prevent race conditions, this
884 	 * TID can only be reused after all in-progress subframes have been
885 	 * completed.
886 	 */
887 	if (txtid->baw_head != txtid->baw_tail)
888 		txtid->state |= AGGR_CLEANUP;
889 	else
890 		txtid->state &= ~AGGR_ADDBA_COMPLETE;
891 	spin_unlock_bh(&txq->axq_lock);
892 
893 	ath_tx_flush_tid(sc, txtid);
894 }
895 
896 void ath_tx_aggr_resume(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid)
897 {
898 	struct ath_atx_tid *txtid;
899 	struct ath_node *an;
900 
901 	an = (struct ath_node *)sta->drv_priv;
902 
903 	if (sc->sc_flags & SC_OP_TXAGGR) {
904 		txtid = ATH_AN_2_TID(an, tid);
905 		txtid->baw_size =
906 			IEEE80211_MIN_AMPDU_BUF << sta->ht_cap.ampdu_factor;
907 		txtid->state |= AGGR_ADDBA_COMPLETE;
908 		txtid->state &= ~AGGR_ADDBA_PROGRESS;
909 		ath_tx_resume_tid(sc, txtid);
910 	}
911 }
912 
913 /********************/
914 /* Queue Management */
915 /********************/
916 
917 static void ath_txq_drain_pending_buffers(struct ath_softc *sc,
918 					  struct ath_txq *txq)
919 {
920 	struct ath_atx_ac *ac, *ac_tmp;
921 	struct ath_atx_tid *tid, *tid_tmp;
922 
923 	list_for_each_entry_safe(ac, ac_tmp, &txq->axq_acq, list) {
924 		list_del(&ac->list);
925 		ac->sched = false;
926 		list_for_each_entry_safe(tid, tid_tmp, &ac->tid_q, list) {
927 			list_del(&tid->list);
928 			tid->sched = false;
929 			ath_tid_drain(sc, txq, tid);
930 		}
931 	}
932 }
933 
934 struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype)
935 {
936 	struct ath_hw *ah = sc->sc_ah;
937 	struct ath_common *common = ath9k_hw_common(ah);
938 	struct ath9k_tx_queue_info qi;
939 	static const int subtype_txq_to_hwq[] = {
940 		[WME_AC_BE] = ATH_TXQ_AC_BE,
941 		[WME_AC_BK] = ATH_TXQ_AC_BK,
942 		[WME_AC_VI] = ATH_TXQ_AC_VI,
943 		[WME_AC_VO] = ATH_TXQ_AC_VO,
944 	};
945 	int qnum, i;
946 
947 	memset(&qi, 0, sizeof(qi));
948 	qi.tqi_subtype = subtype_txq_to_hwq[subtype];
949 	qi.tqi_aifs = ATH9K_TXQ_USEDEFAULT;
950 	qi.tqi_cwmin = ATH9K_TXQ_USEDEFAULT;
951 	qi.tqi_cwmax = ATH9K_TXQ_USEDEFAULT;
952 	qi.tqi_physCompBuf = 0;
953 
954 	/*
955 	 * Enable interrupts only for EOL and DESC conditions.
956 	 * We mark tx descriptors to receive a DESC interrupt
957 	 * when a tx queue gets deep; otherwise waiting for the
958 	 * EOL to reap descriptors.  Note that this is done to
959 	 * reduce interrupt load and this only defers reaping
960 	 * descriptors, never transmitting frames.  Aside from
961 	 * reducing interrupts this also permits more concurrency.
962 	 * The only potential downside is if the tx queue backs
963 	 * up in which case the top half of the kernel may backup
964 	 * due to a lack of tx descriptors.
965 	 *
966 	 * The UAPSD queue is an exception, since we take a desc-
967 	 * based intr on the EOSP frames.
968 	 */
969 	if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
970 		qi.tqi_qflags = TXQ_FLAG_TXOKINT_ENABLE |
971 				TXQ_FLAG_TXERRINT_ENABLE;
972 	} else {
973 		if (qtype == ATH9K_TX_QUEUE_UAPSD)
974 			qi.tqi_qflags = TXQ_FLAG_TXDESCINT_ENABLE;
975 		else
976 			qi.tqi_qflags = TXQ_FLAG_TXEOLINT_ENABLE |
977 					TXQ_FLAG_TXDESCINT_ENABLE;
978 	}
979 	qnum = ath9k_hw_setuptxqueue(ah, qtype, &qi);
980 	if (qnum == -1) {
981 		/*
982 		 * NB: don't print a message, this happens
983 		 * normally on parts with too few tx queues
984 		 */
985 		return NULL;
986 	}
987 	if (qnum >= ARRAY_SIZE(sc->tx.txq)) {
988 		ath_err(common, "qnum %u out of range, max %zu!\n",
989 			qnum, ARRAY_SIZE(sc->tx.txq));
990 		ath9k_hw_releasetxqueue(ah, qnum);
991 		return NULL;
992 	}
993 	if (!ATH_TXQ_SETUP(sc, qnum)) {
994 		struct ath_txq *txq = &sc->tx.txq[qnum];
995 
996 		txq->axq_qnum = qnum;
997 		txq->axq_link = NULL;
998 		INIT_LIST_HEAD(&txq->axq_q);
999 		INIT_LIST_HEAD(&txq->axq_acq);
1000 		spin_lock_init(&txq->axq_lock);
1001 		txq->axq_depth = 0;
1002 		txq->axq_ampdu_depth = 0;
1003 		txq->axq_tx_inprogress = false;
1004 		sc->tx.txqsetup |= 1<<qnum;
1005 
1006 		txq->txq_headidx = txq->txq_tailidx = 0;
1007 		for (i = 0; i < ATH_TXFIFO_DEPTH; i++)
1008 			INIT_LIST_HEAD(&txq->txq_fifo[i]);
1009 		INIT_LIST_HEAD(&txq->txq_fifo_pending);
1010 	}
1011 	return &sc->tx.txq[qnum];
1012 }
1013 
1014 int ath_txq_update(struct ath_softc *sc, int qnum,
1015 		   struct ath9k_tx_queue_info *qinfo)
1016 {
1017 	struct ath_hw *ah = sc->sc_ah;
1018 	int error = 0;
1019 	struct ath9k_tx_queue_info qi;
1020 
1021 	if (qnum == sc->beacon.beaconq) {
1022 		/*
1023 		 * XXX: for beacon queue, we just save the parameter.
1024 		 * It will be picked up by ath_beaconq_config when
1025 		 * it's necessary.
1026 		 */
1027 		sc->beacon.beacon_qi = *qinfo;
1028 		return 0;
1029 	}
1030 
1031 	BUG_ON(sc->tx.txq[qnum].axq_qnum != qnum);
1032 
1033 	ath9k_hw_get_txq_props(ah, qnum, &qi);
1034 	qi.tqi_aifs = qinfo->tqi_aifs;
1035 	qi.tqi_cwmin = qinfo->tqi_cwmin;
1036 	qi.tqi_cwmax = qinfo->tqi_cwmax;
1037 	qi.tqi_burstTime = qinfo->tqi_burstTime;
1038 	qi.tqi_readyTime = qinfo->tqi_readyTime;
1039 
1040 	if (!ath9k_hw_set_txq_props(ah, qnum, &qi)) {
1041 		ath_err(ath9k_hw_common(sc->sc_ah),
1042 			"Unable to update hardware queue %u!\n", qnum);
1043 		error = -EIO;
1044 	} else {
1045 		ath9k_hw_resettxqueue(ah, qnum);
1046 	}
1047 
1048 	return error;
1049 }
1050 
1051 int ath_cabq_update(struct ath_softc *sc)
1052 {
1053 	struct ath9k_tx_queue_info qi;
1054 	int qnum = sc->beacon.cabq->axq_qnum;
1055 
1056 	ath9k_hw_get_txq_props(sc->sc_ah, qnum, &qi);
1057 	/*
1058 	 * Ensure the readytime % is within the bounds.
1059 	 */
1060 	if (sc->config.cabqReadytime < ATH9K_READY_TIME_LO_BOUND)
1061 		sc->config.cabqReadytime = ATH9K_READY_TIME_LO_BOUND;
1062 	else if (sc->config.cabqReadytime > ATH9K_READY_TIME_HI_BOUND)
1063 		sc->config.cabqReadytime = ATH9K_READY_TIME_HI_BOUND;
1064 
1065 	qi.tqi_readyTime = (sc->beacon_interval *
1066 			    sc->config.cabqReadytime) / 100;
1067 	ath_txq_update(sc, qnum, &qi);
1068 
1069 	return 0;
1070 }
1071 
1072 static bool bf_is_ampdu_not_probing(struct ath_buf *bf)
1073 {
1074     struct ieee80211_tx_info *info = IEEE80211_SKB_CB(bf->bf_mpdu);
1075     return bf_isampdu(bf) && !(info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE);
1076 }
1077 
1078 /*
1079  * Drain a given TX queue (could be Beacon or Data)
1080  *
1081  * This assumes output has been stopped and
1082  * we do not need to block ath_tx_tasklet.
1083  */
1084 void ath_draintxq(struct ath_softc *sc, struct ath_txq *txq, bool retry_tx)
1085 {
1086 	struct ath_buf *bf, *lastbf;
1087 	struct list_head bf_head;
1088 	struct ath_tx_status ts;
1089 
1090 	memset(&ts, 0, sizeof(ts));
1091 	INIT_LIST_HEAD(&bf_head);
1092 
1093 	for (;;) {
1094 		spin_lock_bh(&txq->axq_lock);
1095 
1096 		if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
1097 			if (list_empty(&txq->txq_fifo[txq->txq_tailidx])) {
1098 				txq->txq_headidx = txq->txq_tailidx = 0;
1099 				spin_unlock_bh(&txq->axq_lock);
1100 				break;
1101 			} else {
1102 				bf = list_first_entry(&txq->txq_fifo[txq->txq_tailidx],
1103 						      struct ath_buf, list);
1104 			}
1105 		} else {
1106 			if (list_empty(&txq->axq_q)) {
1107 				txq->axq_link = NULL;
1108 				spin_unlock_bh(&txq->axq_lock);
1109 				break;
1110 			}
1111 			bf = list_first_entry(&txq->axq_q, struct ath_buf,
1112 					      list);
1113 
1114 			if (bf->bf_stale) {
1115 				list_del(&bf->list);
1116 				spin_unlock_bh(&txq->axq_lock);
1117 
1118 				ath_tx_return_buffer(sc, bf);
1119 				continue;
1120 			}
1121 		}
1122 
1123 		lastbf = bf->bf_lastbf;
1124 
1125 		if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
1126 			list_cut_position(&bf_head,
1127 					  &txq->txq_fifo[txq->txq_tailidx],
1128 					  &lastbf->list);
1129 			INCR(txq->txq_tailidx, ATH_TXFIFO_DEPTH);
1130 		} else {
1131 			/* remove ath_buf's of the same mpdu from txq */
1132 			list_cut_position(&bf_head, &txq->axq_q, &lastbf->list);
1133 		}
1134 
1135 		txq->axq_depth--;
1136 		if (bf_is_ampdu_not_probing(bf))
1137 			txq->axq_ampdu_depth--;
1138 		spin_unlock_bh(&txq->axq_lock);
1139 
1140 		if (bf_isampdu(bf))
1141 			ath_tx_complete_aggr(sc, txq, bf, &bf_head, &ts, 0,
1142 					     retry_tx);
1143 		else
1144 			ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0, 0);
1145 	}
1146 
1147 	spin_lock_bh(&txq->axq_lock);
1148 	txq->axq_tx_inprogress = false;
1149 	spin_unlock_bh(&txq->axq_lock);
1150 
1151 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
1152 		spin_lock_bh(&txq->axq_lock);
1153 		while (!list_empty(&txq->txq_fifo_pending)) {
1154 			bf = list_first_entry(&txq->txq_fifo_pending,
1155 					      struct ath_buf, list);
1156 			list_cut_position(&bf_head,
1157 					  &txq->txq_fifo_pending,
1158 					  &bf->bf_lastbf->list);
1159 			spin_unlock_bh(&txq->axq_lock);
1160 
1161 			if (bf_isampdu(bf))
1162 				ath_tx_complete_aggr(sc, txq, bf, &bf_head,
1163 						     &ts, 0, retry_tx);
1164 			else
1165 				ath_tx_complete_buf(sc, bf, txq, &bf_head,
1166 						    &ts, 0, 0);
1167 			spin_lock_bh(&txq->axq_lock);
1168 		}
1169 		spin_unlock_bh(&txq->axq_lock);
1170 	}
1171 
1172 	/* flush any pending frames if aggregation is enabled */
1173 	if (sc->sc_flags & SC_OP_TXAGGR) {
1174 		if (!retry_tx) {
1175 			spin_lock_bh(&txq->axq_lock);
1176 			ath_txq_drain_pending_buffers(sc, txq);
1177 			spin_unlock_bh(&txq->axq_lock);
1178 		}
1179 	}
1180 }
1181 
1182 bool ath_drain_all_txq(struct ath_softc *sc, bool retry_tx)
1183 {
1184 	struct ath_hw *ah = sc->sc_ah;
1185 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1186 	struct ath_txq *txq;
1187 	int i, npend = 0;
1188 
1189 	if (sc->sc_flags & SC_OP_INVALID)
1190 		return true;
1191 
1192 	/* Stop beacon queue */
1193 	ath9k_hw_stoptxdma(sc->sc_ah, sc->beacon.beaconq);
1194 
1195 	/* Stop data queues */
1196 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
1197 		if (ATH_TXQ_SETUP(sc, i)) {
1198 			txq = &sc->tx.txq[i];
1199 			ath9k_hw_stoptxdma(ah, txq->axq_qnum);
1200 			npend += ath9k_hw_numtxpending(ah, txq->axq_qnum);
1201 		}
1202 	}
1203 
1204 	if (npend)
1205 		ath_err(common, "Failed to stop TX DMA!\n");
1206 
1207 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
1208 		if (ATH_TXQ_SETUP(sc, i))
1209 			ath_draintxq(sc, &sc->tx.txq[i], retry_tx);
1210 	}
1211 
1212 	return !npend;
1213 }
1214 
1215 void ath_tx_cleanupq(struct ath_softc *sc, struct ath_txq *txq)
1216 {
1217 	ath9k_hw_releasetxqueue(sc->sc_ah, txq->axq_qnum);
1218 	sc->tx.txqsetup &= ~(1<<txq->axq_qnum);
1219 }
1220 
1221 void ath_txq_schedule(struct ath_softc *sc, struct ath_txq *txq)
1222 {
1223 	struct ath_atx_ac *ac;
1224 	struct ath_atx_tid *tid;
1225 
1226 	if (list_empty(&txq->axq_acq))
1227 		return;
1228 
1229 	ac = list_first_entry(&txq->axq_acq, struct ath_atx_ac, list);
1230 	list_del(&ac->list);
1231 	ac->sched = false;
1232 
1233 	do {
1234 		if (list_empty(&ac->tid_q))
1235 			return;
1236 
1237 		tid = list_first_entry(&ac->tid_q, struct ath_atx_tid, list);
1238 		list_del(&tid->list);
1239 		tid->sched = false;
1240 
1241 		if (tid->paused)
1242 			continue;
1243 
1244 		ath_tx_sched_aggr(sc, txq, tid);
1245 
1246 		/*
1247 		 * add tid to round-robin queue if more frames
1248 		 * are pending for the tid
1249 		 */
1250 		if (!list_empty(&tid->buf_q))
1251 			ath_tx_queue_tid(txq, tid);
1252 
1253 		break;
1254 	} while (!list_empty(&ac->tid_q));
1255 
1256 	if (!list_empty(&ac->tid_q)) {
1257 		if (!ac->sched) {
1258 			ac->sched = true;
1259 			list_add_tail(&ac->list, &txq->axq_acq);
1260 		}
1261 	}
1262 }
1263 
1264 /***********/
1265 /* TX, DMA */
1266 /***********/
1267 
1268 /*
1269  * Insert a chain of ath_buf (descriptors) on a txq and
1270  * assume the descriptors are already chained together by caller.
1271  */
1272 static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq,
1273 			     struct list_head *head)
1274 {
1275 	struct ath_hw *ah = sc->sc_ah;
1276 	struct ath_common *common = ath9k_hw_common(ah);
1277 	struct ath_buf *bf;
1278 
1279 	/*
1280 	 * Insert the frame on the outbound list and
1281 	 * pass it on to the hardware.
1282 	 */
1283 
1284 	if (list_empty(head))
1285 		return;
1286 
1287 	bf = list_first_entry(head, struct ath_buf, list);
1288 
1289 	ath_dbg(common, ATH_DBG_QUEUE,
1290 		"qnum: %d, txq depth: %d\n", txq->axq_qnum, txq->axq_depth);
1291 
1292 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
1293 		if (txq->axq_depth >= ATH_TXFIFO_DEPTH) {
1294 			list_splice_tail_init(head, &txq->txq_fifo_pending);
1295 			return;
1296 		}
1297 		if (!list_empty(&txq->txq_fifo[txq->txq_headidx]))
1298 			ath_dbg(common, ATH_DBG_XMIT,
1299 				"Initializing tx fifo %d which is non-empty\n",
1300 				txq->txq_headidx);
1301 		INIT_LIST_HEAD(&txq->txq_fifo[txq->txq_headidx]);
1302 		list_splice_init(head, &txq->txq_fifo[txq->txq_headidx]);
1303 		INCR(txq->txq_headidx, ATH_TXFIFO_DEPTH);
1304 		ath9k_hw_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
1305 		ath_dbg(common, ATH_DBG_XMIT, "TXDP[%u] = %llx (%p)\n",
1306 			txq->axq_qnum, ito64(bf->bf_daddr), bf->bf_desc);
1307 	} else {
1308 		list_splice_tail_init(head, &txq->axq_q);
1309 
1310 		if (txq->axq_link == NULL) {
1311 			ath9k_hw_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
1312 			ath_dbg(common, ATH_DBG_XMIT, "TXDP[%u] = %llx (%p)\n",
1313 				txq->axq_qnum, ito64(bf->bf_daddr),
1314 				bf->bf_desc);
1315 		} else {
1316 			*txq->axq_link = bf->bf_daddr;
1317 			ath_dbg(common, ATH_DBG_XMIT,
1318 				"link[%u] (%p)=%llx (%p)\n",
1319 				txq->axq_qnum, txq->axq_link,
1320 				ito64(bf->bf_daddr), bf->bf_desc);
1321 		}
1322 		ath9k_hw_get_desc_link(ah, bf->bf_lastbf->bf_desc,
1323 				       &txq->axq_link);
1324 		ath9k_hw_txstart(ah, txq->axq_qnum);
1325 	}
1326 	txq->axq_depth++;
1327 	if (bf_is_ampdu_not_probing(bf))
1328 		txq->axq_ampdu_depth++;
1329 }
1330 
1331 static void ath_tx_send_ampdu(struct ath_softc *sc, struct ath_atx_tid *tid,
1332 			      struct ath_buf *bf, struct ath_tx_control *txctl)
1333 {
1334 	struct ath_frame_info *fi = get_frame_info(bf->bf_mpdu);
1335 	struct list_head bf_head;
1336 
1337 	bf->bf_state.bf_type |= BUF_AMPDU;
1338 	TX_STAT_INC(txctl->txq->axq_qnum, a_queued);
1339 
1340 	/*
1341 	 * Do not queue to h/w when any of the following conditions is true:
1342 	 * - there are pending frames in software queue
1343 	 * - the TID is currently paused for ADDBA/BAR request
1344 	 * - seqno is not within block-ack window
1345 	 * - h/w queue depth exceeds low water mark
1346 	 */
1347 	if (!list_empty(&tid->buf_q) || tid->paused ||
1348 	    !BAW_WITHIN(tid->seq_start, tid->baw_size, fi->seqno) ||
1349 	    txctl->txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH) {
1350 		/*
1351 		 * Add this frame to software queue for scheduling later
1352 		 * for aggregation.
1353 		 */
1354 		list_add_tail(&bf->list, &tid->buf_q);
1355 		ath_tx_queue_tid(txctl->txq, tid);
1356 		return;
1357 	}
1358 
1359 	INIT_LIST_HEAD(&bf_head);
1360 	list_add(&bf->list, &bf_head);
1361 
1362 	/* Add sub-frame to BAW */
1363 	if (!fi->retries)
1364 		ath_tx_addto_baw(sc, tid, fi->seqno);
1365 
1366 	/* Queue to h/w without aggregation */
1367 	bf->bf_lastbf = bf;
1368 	ath_buf_set_rate(sc, bf, fi->framelen);
1369 	ath_tx_txqaddbuf(sc, txctl->txq, &bf_head);
1370 }
1371 
1372 static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
1373 			       struct ath_atx_tid *tid,
1374 			       struct list_head *bf_head)
1375 {
1376 	struct ath_frame_info *fi;
1377 	struct ath_buf *bf;
1378 
1379 	bf = list_first_entry(bf_head, struct ath_buf, list);
1380 	bf->bf_state.bf_type &= ~BUF_AMPDU;
1381 
1382 	/* update starting sequence number for subsequent ADDBA request */
1383 	if (tid)
1384 		INCR(tid->seq_start, IEEE80211_SEQ_MAX);
1385 
1386 	bf->bf_lastbf = bf;
1387 	fi = get_frame_info(bf->bf_mpdu);
1388 	ath_buf_set_rate(sc, bf, fi->framelen);
1389 	ath_tx_txqaddbuf(sc, txq, bf_head);
1390 	TX_STAT_INC(txq->axq_qnum, queued);
1391 }
1392 
1393 static enum ath9k_pkt_type get_hw_packet_type(struct sk_buff *skb)
1394 {
1395 	struct ieee80211_hdr *hdr;
1396 	enum ath9k_pkt_type htype;
1397 	__le16 fc;
1398 
1399 	hdr = (struct ieee80211_hdr *)skb->data;
1400 	fc = hdr->frame_control;
1401 
1402 	if (ieee80211_is_beacon(fc))
1403 		htype = ATH9K_PKT_TYPE_BEACON;
1404 	else if (ieee80211_is_probe_resp(fc))
1405 		htype = ATH9K_PKT_TYPE_PROBE_RESP;
1406 	else if (ieee80211_is_atim(fc))
1407 		htype = ATH9K_PKT_TYPE_ATIM;
1408 	else if (ieee80211_is_pspoll(fc))
1409 		htype = ATH9K_PKT_TYPE_PSPOLL;
1410 	else
1411 		htype = ATH9K_PKT_TYPE_NORMAL;
1412 
1413 	return htype;
1414 }
1415 
1416 static void setup_frame_info(struct ieee80211_hw *hw, struct sk_buff *skb,
1417 			     int framelen)
1418 {
1419 	struct ath_wiphy *aphy = hw->priv;
1420 	struct ath_softc *sc = aphy->sc;
1421 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1422 	struct ieee80211_sta *sta = tx_info->control.sta;
1423 	struct ieee80211_key_conf *hw_key = tx_info->control.hw_key;
1424 	struct ieee80211_hdr *hdr;
1425 	struct ath_frame_info *fi = get_frame_info(skb);
1426 	struct ath_node *an;
1427 	struct ath_atx_tid *tid;
1428 	enum ath9k_key_type keytype;
1429 	u16 seqno = 0;
1430 	u8 tidno;
1431 
1432 	keytype = ath9k_cmn_get_hw_crypto_keytype(skb);
1433 
1434 	hdr = (struct ieee80211_hdr *)skb->data;
1435 	if (sta && ieee80211_is_data_qos(hdr->frame_control) &&
1436 		conf_is_ht(&hw->conf) && (sc->sc_flags & SC_OP_TXAGGR)) {
1437 
1438 		an = (struct ath_node *) sta->drv_priv;
1439 		tidno = ieee80211_get_qos_ctl(hdr)[0] & IEEE80211_QOS_CTL_TID_MASK;
1440 
1441 		/*
1442 		 * Override seqno set by upper layer with the one
1443 		 * in tx aggregation state.
1444 		 */
1445 		tid = ATH_AN_2_TID(an, tidno);
1446 		seqno = tid->seq_next;
1447 		hdr->seq_ctrl = cpu_to_le16(seqno << IEEE80211_SEQ_SEQ_SHIFT);
1448 		INCR(tid->seq_next, IEEE80211_SEQ_MAX);
1449 	}
1450 
1451 	memset(fi, 0, sizeof(*fi));
1452 	if (hw_key)
1453 		fi->keyix = hw_key->hw_key_idx;
1454 	else
1455 		fi->keyix = ATH9K_TXKEYIX_INVALID;
1456 	fi->keytype = keytype;
1457 	fi->framelen = framelen;
1458 	fi->seqno = seqno;
1459 }
1460 
1461 static int setup_tx_flags(struct sk_buff *skb)
1462 {
1463 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1464 	int flags = 0;
1465 
1466 	flags |= ATH9K_TXDESC_CLRDMASK; /* needed for crypto errors */
1467 	flags |= ATH9K_TXDESC_INTREQ;
1468 
1469 	if (tx_info->flags & IEEE80211_TX_CTL_NO_ACK)
1470 		flags |= ATH9K_TXDESC_NOACK;
1471 
1472 	if (tx_info->flags & IEEE80211_TX_CTL_LDPC)
1473 		flags |= ATH9K_TXDESC_LDPC;
1474 
1475 	return flags;
1476 }
1477 
1478 /*
1479  * rix - rate index
1480  * pktlen - total bytes (delims + data + fcs + pads + pad delims)
1481  * width  - 0 for 20 MHz, 1 for 40 MHz
1482  * half_gi - to use 4us v/s 3.6 us for symbol time
1483  */
1484 static u32 ath_pkt_duration(struct ath_softc *sc, u8 rix, int pktlen,
1485 			    int width, int half_gi, bool shortPreamble)
1486 {
1487 	u32 nbits, nsymbits, duration, nsymbols;
1488 	int streams;
1489 
1490 	/* find number of symbols: PLCP + data */
1491 	streams = HT_RC_2_STREAMS(rix);
1492 	nbits = (pktlen << 3) + OFDM_PLCP_BITS;
1493 	nsymbits = bits_per_symbol[rix % 8][width] * streams;
1494 	nsymbols = (nbits + nsymbits - 1) / nsymbits;
1495 
1496 	if (!half_gi)
1497 		duration = SYMBOL_TIME(nsymbols);
1498 	else
1499 		duration = SYMBOL_TIME_HALFGI(nsymbols);
1500 
1501 	/* addup duration for legacy/ht training and signal fields */
1502 	duration += L_STF + L_LTF + L_SIG + HT_SIG + HT_STF + HT_LTF(streams);
1503 
1504 	return duration;
1505 }
1506 
1507 u8 ath_txchainmask_reduction(struct ath_softc *sc, u8 chainmask, u32 rate)
1508 {
1509 	struct ath_hw *ah = sc->sc_ah;
1510 	struct ath9k_channel *curchan = ah->curchan;
1511 	if ((sc->sc_flags & SC_OP_ENABLE_APM) &&
1512 			(curchan->channelFlags & CHANNEL_5GHZ) &&
1513 			(chainmask == 0x7) && (rate < 0x90))
1514 		return 0x3;
1515 	else
1516 		return chainmask;
1517 }
1518 
1519 static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf, int len)
1520 {
1521 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1522 	struct ath9k_11n_rate_series series[4];
1523 	struct sk_buff *skb;
1524 	struct ieee80211_tx_info *tx_info;
1525 	struct ieee80211_tx_rate *rates;
1526 	const struct ieee80211_rate *rate;
1527 	struct ieee80211_hdr *hdr;
1528 	int i, flags = 0;
1529 	u8 rix = 0, ctsrate = 0;
1530 	bool is_pspoll;
1531 
1532 	memset(series, 0, sizeof(struct ath9k_11n_rate_series) * 4);
1533 
1534 	skb = bf->bf_mpdu;
1535 	tx_info = IEEE80211_SKB_CB(skb);
1536 	rates = tx_info->control.rates;
1537 	hdr = (struct ieee80211_hdr *)skb->data;
1538 	is_pspoll = ieee80211_is_pspoll(hdr->frame_control);
1539 
1540 	/*
1541 	 * We check if Short Preamble is needed for the CTS rate by
1542 	 * checking the BSS's global flag.
1543 	 * But for the rate series, IEEE80211_TX_RC_USE_SHORT_PREAMBLE is used.
1544 	 */
1545 	rate = ieee80211_get_rts_cts_rate(sc->hw, tx_info);
1546 	ctsrate = rate->hw_value;
1547 	if (sc->sc_flags & SC_OP_PREAMBLE_SHORT)
1548 		ctsrate |= rate->hw_value_short;
1549 
1550 	for (i = 0; i < 4; i++) {
1551 		bool is_40, is_sgi, is_sp;
1552 		int phy;
1553 
1554 		if (!rates[i].count || (rates[i].idx < 0))
1555 			continue;
1556 
1557 		rix = rates[i].idx;
1558 		series[i].Tries = rates[i].count;
1559 
1560 		if ((sc->config.ath_aggr_prot && bf_isaggr(bf)) ||
1561 		    (rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS)) {
1562 			series[i].RateFlags |= ATH9K_RATESERIES_RTS_CTS;
1563 			flags |= ATH9K_TXDESC_RTSENA;
1564 		} else if (rates[i].flags & IEEE80211_TX_RC_USE_CTS_PROTECT) {
1565 			series[i].RateFlags |= ATH9K_RATESERIES_RTS_CTS;
1566 			flags |= ATH9K_TXDESC_CTSENA;
1567 		}
1568 
1569 		if (rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
1570 			series[i].RateFlags |= ATH9K_RATESERIES_2040;
1571 		if (rates[i].flags & IEEE80211_TX_RC_SHORT_GI)
1572 			series[i].RateFlags |= ATH9K_RATESERIES_HALFGI;
1573 
1574 		is_sgi = !!(rates[i].flags & IEEE80211_TX_RC_SHORT_GI);
1575 		is_40 = !!(rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH);
1576 		is_sp = !!(rates[i].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
1577 
1578 		if (rates[i].flags & IEEE80211_TX_RC_MCS) {
1579 			/* MCS rates */
1580 			series[i].Rate = rix | 0x80;
1581 			series[i].ChSel = ath_txchainmask_reduction(sc,
1582 					common->tx_chainmask, series[i].Rate);
1583 			series[i].PktDuration = ath_pkt_duration(sc, rix, len,
1584 				 is_40, is_sgi, is_sp);
1585 			if (rix < 8 && (tx_info->flags & IEEE80211_TX_CTL_STBC))
1586 				series[i].RateFlags |= ATH9K_RATESERIES_STBC;
1587 			continue;
1588 		}
1589 
1590 		/* legacy rates */
1591 		if ((tx_info->band == IEEE80211_BAND_2GHZ) &&
1592 		    !(rate->flags & IEEE80211_RATE_ERP_G))
1593 			phy = WLAN_RC_PHY_CCK;
1594 		else
1595 			phy = WLAN_RC_PHY_OFDM;
1596 
1597 		rate = &sc->sbands[tx_info->band].bitrates[rates[i].idx];
1598 		series[i].Rate = rate->hw_value;
1599 		if (rate->hw_value_short) {
1600 			if (rates[i].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
1601 				series[i].Rate |= rate->hw_value_short;
1602 		} else {
1603 			is_sp = false;
1604 		}
1605 
1606 		if (bf->bf_state.bfs_paprd)
1607 			series[i].ChSel = common->tx_chainmask;
1608 		else
1609 			series[i].ChSel = ath_txchainmask_reduction(sc,
1610 					common->tx_chainmask, series[i].Rate);
1611 
1612 		series[i].PktDuration = ath9k_hw_computetxtime(sc->sc_ah,
1613 			phy, rate->bitrate * 100, len, rix, is_sp);
1614 	}
1615 
1616 	/* For AR5416 - RTS cannot be followed by a frame larger than 8K */
1617 	if (bf_isaggr(bf) && (len > sc->sc_ah->caps.rts_aggr_limit))
1618 		flags &= ~ATH9K_TXDESC_RTSENA;
1619 
1620 	/* ATH9K_TXDESC_RTSENA and ATH9K_TXDESC_CTSENA are mutually exclusive. */
1621 	if (flags & ATH9K_TXDESC_RTSENA)
1622 		flags &= ~ATH9K_TXDESC_CTSENA;
1623 
1624 	/* set dur_update_en for l-sig computation except for PS-Poll frames */
1625 	ath9k_hw_set11n_ratescenario(sc->sc_ah, bf->bf_desc,
1626 				     bf->bf_lastbf->bf_desc,
1627 				     !is_pspoll, ctsrate,
1628 				     0, series, 4, flags);
1629 
1630 	if (sc->config.ath_aggr_prot && flags)
1631 		ath9k_hw_set11n_burstduration(sc->sc_ah, bf->bf_desc, 8192);
1632 }
1633 
1634 static struct ath_buf *ath_tx_setup_buffer(struct ieee80211_hw *hw,
1635 					   struct ath_txq *txq,
1636 					   struct sk_buff *skb)
1637 {
1638 	struct ath_wiphy *aphy = hw->priv;
1639 	struct ath_softc *sc = aphy->sc;
1640 	struct ath_hw *ah = sc->sc_ah;
1641 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1642 	struct ath_frame_info *fi = get_frame_info(skb);
1643 	struct ath_buf *bf;
1644 	struct ath_desc *ds;
1645 	int frm_type;
1646 
1647 	bf = ath_tx_get_buffer(sc);
1648 	if (!bf) {
1649 		ath_dbg(common, ATH_DBG_XMIT, "TX buffers are full\n");
1650 		return NULL;
1651 	}
1652 
1653 	ATH_TXBUF_RESET(bf);
1654 
1655 	bf->aphy = aphy;
1656 	bf->bf_flags = setup_tx_flags(skb);
1657 	bf->bf_mpdu = skb;
1658 
1659 	bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
1660 					 skb->len, DMA_TO_DEVICE);
1661 	if (unlikely(dma_mapping_error(sc->dev, bf->bf_buf_addr))) {
1662 		bf->bf_mpdu = NULL;
1663 		bf->bf_buf_addr = 0;
1664 		ath_err(ath9k_hw_common(sc->sc_ah),
1665 			"dma_mapping_error() on TX\n");
1666 		ath_tx_return_buffer(sc, bf);
1667 		return NULL;
1668 	}
1669 
1670 	frm_type = get_hw_packet_type(skb);
1671 
1672 	ds = bf->bf_desc;
1673 	ath9k_hw_set_desc_link(ah, ds, 0);
1674 
1675 	ath9k_hw_set11n_txdesc(ah, ds, fi->framelen, frm_type, MAX_RATE_POWER,
1676 			       fi->keyix, fi->keytype, bf->bf_flags);
1677 
1678 	ath9k_hw_filltxdesc(ah, ds,
1679 			    skb->len,	/* segment length */
1680 			    true,	/* first segment */
1681 			    true,	/* last segment */
1682 			    ds,		/* first descriptor */
1683 			    bf->bf_buf_addr,
1684 			    txq->axq_qnum);
1685 
1686 
1687 	return bf;
1688 }
1689 
1690 /* FIXME: tx power */
1691 static void ath_tx_start_dma(struct ath_softc *sc, struct ath_buf *bf,
1692 			     struct ath_tx_control *txctl)
1693 {
1694 	struct sk_buff *skb = bf->bf_mpdu;
1695 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1696 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1697 	struct list_head bf_head;
1698 	struct ath_atx_tid *tid = NULL;
1699 	u8 tidno;
1700 
1701 	spin_lock_bh(&txctl->txq->axq_lock);
1702 
1703 	if (ieee80211_is_data_qos(hdr->frame_control) && txctl->an) {
1704 		tidno = ieee80211_get_qos_ctl(hdr)[0] &
1705 			IEEE80211_QOS_CTL_TID_MASK;
1706 		tid = ATH_AN_2_TID(txctl->an, tidno);
1707 
1708 		WARN_ON(tid->ac->txq != txctl->txq);
1709 	}
1710 
1711 	if ((tx_info->flags & IEEE80211_TX_CTL_AMPDU) && tid) {
1712 		/*
1713 		 * Try aggregation if it's a unicast data frame
1714 		 * and the destination is HT capable.
1715 		 */
1716 		ath_tx_send_ampdu(sc, tid, bf, txctl);
1717 	} else {
1718 		INIT_LIST_HEAD(&bf_head);
1719 		list_add_tail(&bf->list, &bf_head);
1720 
1721 		bf->bf_state.bfs_ftype = txctl->frame_type;
1722 		bf->bf_state.bfs_paprd = txctl->paprd;
1723 
1724 		if (bf->bf_state.bfs_paprd)
1725 			ar9003_hw_set_paprd_txdesc(sc->sc_ah, bf->bf_desc,
1726 						   bf->bf_state.bfs_paprd);
1727 
1728 		if (txctl->paprd)
1729 			bf->bf_state.bfs_paprd_timestamp = jiffies;
1730 
1731 		ath_tx_send_normal(sc, txctl->txq, tid, &bf_head);
1732 	}
1733 
1734 	spin_unlock_bh(&txctl->txq->axq_lock);
1735 }
1736 
1737 /* Upon failure caller should free skb */
1738 int ath_tx_start(struct ieee80211_hw *hw, struct sk_buff *skb,
1739 		 struct ath_tx_control *txctl)
1740 {
1741 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1742 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1743 	struct ieee80211_sta *sta = info->control.sta;
1744 	struct ath_wiphy *aphy = hw->priv;
1745 	struct ath_softc *sc = aphy->sc;
1746 	struct ath_txq *txq = txctl->txq;
1747 	struct ath_buf *bf;
1748 	int padpos, padsize;
1749 	int frmlen = skb->len + FCS_LEN;
1750 	int q;
1751 
1752 	/* NOTE:  sta can be NULL according to net/mac80211.h */
1753 	if (sta)
1754 		txctl->an = (struct ath_node *)sta->drv_priv;
1755 
1756 	if (info->control.hw_key)
1757 		frmlen += info->control.hw_key->icv_len;
1758 
1759 	/*
1760 	 * As a temporary workaround, assign seq# here; this will likely need
1761 	 * to be cleaned up to work better with Beacon transmission and virtual
1762 	 * BSSes.
1763 	 */
1764 	if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
1765 		if (info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)
1766 			sc->tx.seq_no += 0x10;
1767 		hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
1768 		hdr->seq_ctrl |= cpu_to_le16(sc->tx.seq_no);
1769 	}
1770 
1771 	/* Add the padding after the header if this is not already done */
1772 	padpos = ath9k_cmn_padpos(hdr->frame_control);
1773 	padsize = padpos & 3;
1774 	if (padsize && skb->len > padpos) {
1775 		if (skb_headroom(skb) < padsize)
1776 			return -ENOMEM;
1777 
1778 		skb_push(skb, padsize);
1779 		memmove(skb->data, skb->data + padsize, padpos);
1780 	}
1781 
1782 	setup_frame_info(hw, skb, frmlen);
1783 
1784 	/*
1785 	 * At this point, the vif, hw_key and sta pointers in the tx control
1786 	 * info are no longer valid (overwritten by the ath_frame_info data.
1787 	 */
1788 
1789 	bf = ath_tx_setup_buffer(hw, txctl->txq, skb);
1790 	if (unlikely(!bf))
1791 		return -ENOMEM;
1792 
1793 	q = skb_get_queue_mapping(skb);
1794 	spin_lock_bh(&txq->axq_lock);
1795 	if (txq == sc->tx.txq_map[q] &&
1796 	    ++txq->pending_frames > ATH_MAX_QDEPTH && !txq->stopped) {
1797 		ath_mac80211_stop_queue(sc, q);
1798 		txq->stopped = 1;
1799 	}
1800 	spin_unlock_bh(&txq->axq_lock);
1801 
1802 	ath_tx_start_dma(sc, bf, txctl);
1803 
1804 	return 0;
1805 }
1806 
1807 /*****************/
1808 /* TX Completion */
1809 /*****************/
1810 
1811 static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
1812 			    struct ath_wiphy *aphy, int tx_flags, int ftype,
1813 			    struct ath_txq *txq)
1814 {
1815 	struct ieee80211_hw *hw = sc->hw;
1816 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1817 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1818 	struct ieee80211_hdr * hdr = (struct ieee80211_hdr *)skb->data;
1819 	int q, padpos, padsize;
1820 
1821 	ath_dbg(common, ATH_DBG_XMIT, "TX complete: skb: %p\n", skb);
1822 
1823 	if (aphy)
1824 		hw = aphy->hw;
1825 
1826 	if (tx_flags & ATH_TX_BAR)
1827 		tx_info->flags |= IEEE80211_TX_STAT_AMPDU_NO_BACK;
1828 
1829 	if (!(tx_flags & (ATH_TX_ERROR | ATH_TX_XRETRY))) {
1830 		/* Frame was ACKed */
1831 		tx_info->flags |= IEEE80211_TX_STAT_ACK;
1832 	}
1833 
1834 	padpos = ath9k_cmn_padpos(hdr->frame_control);
1835 	padsize = padpos & 3;
1836 	if (padsize && skb->len>padpos+padsize) {
1837 		/*
1838 		 * Remove MAC header padding before giving the frame back to
1839 		 * mac80211.
1840 		 */
1841 		memmove(skb->data + padsize, skb->data, padpos);
1842 		skb_pull(skb, padsize);
1843 	}
1844 
1845 	if (sc->ps_flags & PS_WAIT_FOR_TX_ACK) {
1846 		sc->ps_flags &= ~PS_WAIT_FOR_TX_ACK;
1847 		ath_dbg(common, ATH_DBG_PS,
1848 			"Going back to sleep after having received TX status (0x%lx)\n",
1849 			sc->ps_flags & (PS_WAIT_FOR_BEACON |
1850 					PS_WAIT_FOR_CAB |
1851 					PS_WAIT_FOR_PSPOLL_DATA |
1852 					PS_WAIT_FOR_TX_ACK));
1853 	}
1854 
1855 	if (unlikely(ftype))
1856 		ath9k_tx_status(hw, skb, ftype);
1857 	else {
1858 		q = skb_get_queue_mapping(skb);
1859 		if (txq == sc->tx.txq_map[q]) {
1860 			spin_lock_bh(&txq->axq_lock);
1861 			if (WARN_ON(--txq->pending_frames < 0))
1862 				txq->pending_frames = 0;
1863 			spin_unlock_bh(&txq->axq_lock);
1864 		}
1865 
1866 		ieee80211_tx_status(hw, skb);
1867 	}
1868 }
1869 
1870 static void ath_tx_complete_buf(struct ath_softc *sc, struct ath_buf *bf,
1871 				struct ath_txq *txq, struct list_head *bf_q,
1872 				struct ath_tx_status *ts, int txok, int sendbar)
1873 {
1874 	struct sk_buff *skb = bf->bf_mpdu;
1875 	unsigned long flags;
1876 	int tx_flags = 0;
1877 
1878 	if (sendbar)
1879 		tx_flags = ATH_TX_BAR;
1880 
1881 	if (!txok) {
1882 		tx_flags |= ATH_TX_ERROR;
1883 
1884 		if (bf_isxretried(bf))
1885 			tx_flags |= ATH_TX_XRETRY;
1886 	}
1887 
1888 	dma_unmap_single(sc->dev, bf->bf_buf_addr, skb->len, DMA_TO_DEVICE);
1889 	bf->bf_buf_addr = 0;
1890 
1891 	if (bf->bf_state.bfs_paprd) {
1892 		if (time_after(jiffies,
1893 				bf->bf_state.bfs_paprd_timestamp +
1894 				msecs_to_jiffies(ATH_PAPRD_TIMEOUT)))
1895 			dev_kfree_skb_any(skb);
1896 		else
1897 			complete(&sc->paprd_complete);
1898 	} else {
1899 		ath_debug_stat_tx(sc, bf, ts);
1900 		ath_tx_complete(sc, skb, bf->aphy, tx_flags,
1901 				bf->bf_state.bfs_ftype, txq);
1902 	}
1903 	/* At this point, skb (bf->bf_mpdu) is consumed...make sure we don't
1904 	 * accidentally reference it later.
1905 	 */
1906 	bf->bf_mpdu = NULL;
1907 
1908 	/*
1909 	 * Return the list of ath_buf of this mpdu to free queue
1910 	 */
1911 	spin_lock_irqsave(&sc->tx.txbuflock, flags);
1912 	list_splice_tail_init(bf_q, &sc->tx.txbuf);
1913 	spin_unlock_irqrestore(&sc->tx.txbuflock, flags);
1914 }
1915 
1916 static void ath_tx_rc_status(struct ath_buf *bf, struct ath_tx_status *ts,
1917 			     int nframes, int nbad, int txok, bool update_rc)
1918 {
1919 	struct sk_buff *skb = bf->bf_mpdu;
1920 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1921 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1922 	struct ieee80211_hw *hw = bf->aphy->hw;
1923 	struct ath_softc *sc = bf->aphy->sc;
1924 	struct ath_hw *ah = sc->sc_ah;
1925 	u8 i, tx_rateindex;
1926 
1927 	if (txok)
1928 		tx_info->status.ack_signal = ts->ts_rssi;
1929 
1930 	tx_rateindex = ts->ts_rateindex;
1931 	WARN_ON(tx_rateindex >= hw->max_rates);
1932 
1933 	if (ts->ts_status & ATH9K_TXERR_FILT)
1934 		tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
1935 	if ((tx_info->flags & IEEE80211_TX_CTL_AMPDU) && update_rc) {
1936 		tx_info->flags |= IEEE80211_TX_STAT_AMPDU;
1937 
1938 		BUG_ON(nbad > nframes);
1939 
1940 		tx_info->status.ampdu_len = nframes;
1941 		tx_info->status.ampdu_ack_len = nframes - nbad;
1942 	}
1943 
1944 	if ((ts->ts_status & ATH9K_TXERR_FILT) == 0 &&
1945 	    (bf->bf_flags & ATH9K_TXDESC_NOACK) == 0 && update_rc) {
1946 		/*
1947 		 * If an underrun error is seen assume it as an excessive
1948 		 * retry only if max frame trigger level has been reached
1949 		 * (2 KB for single stream, and 4 KB for dual stream).
1950 		 * Adjust the long retry as if the frame was tried
1951 		 * hw->max_rate_tries times to affect how rate control updates
1952 		 * PER for the failed rate.
1953 		 * In case of congestion on the bus penalizing this type of
1954 		 * underruns should help hardware actually transmit new frames
1955 		 * successfully by eventually preferring slower rates.
1956 		 * This itself should also alleviate congestion on the bus.
1957 		 */
1958 		if (ieee80211_is_data(hdr->frame_control) &&
1959 		    (ts->ts_flags & (ATH9K_TX_DATA_UNDERRUN |
1960 		                     ATH9K_TX_DELIM_UNDERRUN)) &&
1961 		    ah->tx_trig_level >= sc->sc_ah->caps.tx_triglevel_max)
1962 			tx_info->status.rates[tx_rateindex].count =
1963 				hw->max_rate_tries;
1964 	}
1965 
1966 	for (i = tx_rateindex + 1; i < hw->max_rates; i++) {
1967 		tx_info->status.rates[i].count = 0;
1968 		tx_info->status.rates[i].idx = -1;
1969 	}
1970 
1971 	tx_info->status.rates[tx_rateindex].count = ts->ts_longretry + 1;
1972 }
1973 
1974 static void ath_wake_mac80211_queue(struct ath_softc *sc, int qnum)
1975 {
1976 	struct ath_txq *txq;
1977 
1978 	txq = sc->tx.txq_map[qnum];
1979 	spin_lock_bh(&txq->axq_lock);
1980 	if (txq->stopped && txq->pending_frames < ATH_MAX_QDEPTH) {
1981 		if (ath_mac80211_start_queue(sc, qnum))
1982 			txq->stopped = 0;
1983 	}
1984 	spin_unlock_bh(&txq->axq_lock);
1985 }
1986 
1987 static void ath_tx_processq(struct ath_softc *sc, struct ath_txq *txq)
1988 {
1989 	struct ath_hw *ah = sc->sc_ah;
1990 	struct ath_common *common = ath9k_hw_common(ah);
1991 	struct ath_buf *bf, *lastbf, *bf_held = NULL;
1992 	struct list_head bf_head;
1993 	struct ath_desc *ds;
1994 	struct ath_tx_status ts;
1995 	int txok;
1996 	int status;
1997 	int qnum;
1998 
1999 	ath_dbg(common, ATH_DBG_QUEUE, "tx queue %d (%x), link %p\n",
2000 		txq->axq_qnum, ath9k_hw_gettxbuf(sc->sc_ah, txq->axq_qnum),
2001 		txq->axq_link);
2002 
2003 	for (;;) {
2004 		spin_lock_bh(&txq->axq_lock);
2005 		if (list_empty(&txq->axq_q)) {
2006 			txq->axq_link = NULL;
2007 			spin_unlock_bh(&txq->axq_lock);
2008 			break;
2009 		}
2010 		bf = list_first_entry(&txq->axq_q, struct ath_buf, list);
2011 
2012 		/*
2013 		 * There is a race condition that a BH gets scheduled
2014 		 * after sw writes TxE and before hw re-load the last
2015 		 * descriptor to get the newly chained one.
2016 		 * Software must keep the last DONE descriptor as a
2017 		 * holding descriptor - software does so by marking
2018 		 * it with the STALE flag.
2019 		 */
2020 		bf_held = NULL;
2021 		if (bf->bf_stale) {
2022 			bf_held = bf;
2023 			if (list_is_last(&bf_held->list, &txq->axq_q)) {
2024 				spin_unlock_bh(&txq->axq_lock);
2025 				break;
2026 			} else {
2027 				bf = list_entry(bf_held->list.next,
2028 						struct ath_buf, list);
2029 			}
2030 		}
2031 
2032 		lastbf = bf->bf_lastbf;
2033 		ds = lastbf->bf_desc;
2034 
2035 		memset(&ts, 0, sizeof(ts));
2036 		status = ath9k_hw_txprocdesc(ah, ds, &ts);
2037 		if (status == -EINPROGRESS) {
2038 			spin_unlock_bh(&txq->axq_lock);
2039 			break;
2040 		}
2041 
2042 		/*
2043 		 * Remove ath_buf's of the same transmit unit from txq,
2044 		 * however leave the last descriptor back as the holding
2045 		 * descriptor for hw.
2046 		 */
2047 		lastbf->bf_stale = true;
2048 		INIT_LIST_HEAD(&bf_head);
2049 		if (!list_is_singular(&lastbf->list))
2050 			list_cut_position(&bf_head,
2051 				&txq->axq_q, lastbf->list.prev);
2052 
2053 		txq->axq_depth--;
2054 		txok = !(ts.ts_status & ATH9K_TXERR_MASK);
2055 		txq->axq_tx_inprogress = false;
2056 		if (bf_held)
2057 			list_del(&bf_held->list);
2058 
2059 		if (bf_is_ampdu_not_probing(bf))
2060 			txq->axq_ampdu_depth--;
2061 		spin_unlock_bh(&txq->axq_lock);
2062 
2063 		if (bf_held)
2064 			ath_tx_return_buffer(sc, bf_held);
2065 
2066 		if (!bf_isampdu(bf)) {
2067 			/*
2068 			 * This frame is sent out as a single frame.
2069 			 * Use hardware retry status for this frame.
2070 			 */
2071 			if (ts.ts_status & ATH9K_TXERR_XRETRY)
2072 				bf->bf_state.bf_type |= BUF_XRETRY;
2073 			ath_tx_rc_status(bf, &ts, 1, txok ? 0 : 1, txok, true);
2074 		}
2075 
2076 		qnum = skb_get_queue_mapping(bf->bf_mpdu);
2077 
2078 		if (bf_isampdu(bf))
2079 			ath_tx_complete_aggr(sc, txq, bf, &bf_head, &ts, txok,
2080 					     true);
2081 		else
2082 			ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, txok, 0);
2083 
2084 		if (txq == sc->tx.txq_map[qnum])
2085 			ath_wake_mac80211_queue(sc, qnum);
2086 
2087 		spin_lock_bh(&txq->axq_lock);
2088 		if (sc->sc_flags & SC_OP_TXAGGR)
2089 			ath_txq_schedule(sc, txq);
2090 		spin_unlock_bh(&txq->axq_lock);
2091 	}
2092 }
2093 
2094 static void ath_tx_complete_poll_work(struct work_struct *work)
2095 {
2096 	struct ath_softc *sc = container_of(work, struct ath_softc,
2097 			tx_complete_work.work);
2098 	struct ath_txq *txq;
2099 	int i;
2100 	bool needreset = false;
2101 
2102 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++)
2103 		if (ATH_TXQ_SETUP(sc, i)) {
2104 			txq = &sc->tx.txq[i];
2105 			spin_lock_bh(&txq->axq_lock);
2106 			if (txq->axq_depth) {
2107 				if (txq->axq_tx_inprogress) {
2108 					needreset = true;
2109 					spin_unlock_bh(&txq->axq_lock);
2110 					break;
2111 				} else {
2112 					txq->axq_tx_inprogress = true;
2113 				}
2114 			}
2115 			spin_unlock_bh(&txq->axq_lock);
2116 		}
2117 
2118 	if (needreset) {
2119 		ath_dbg(ath9k_hw_common(sc->sc_ah), ATH_DBG_RESET,
2120 			"tx hung, resetting the chip\n");
2121 		ath_reset(sc, true);
2122 	}
2123 
2124 	ieee80211_queue_delayed_work(sc->hw, &sc->tx_complete_work,
2125 			msecs_to_jiffies(ATH_TX_COMPLETE_POLL_INT));
2126 }
2127 
2128 
2129 
2130 void ath_tx_tasklet(struct ath_softc *sc)
2131 {
2132 	int i;
2133 	u32 qcumask = ((1 << ATH9K_NUM_TX_QUEUES) - 1);
2134 
2135 	ath9k_hw_gettxintrtxqs(sc->sc_ah, &qcumask);
2136 
2137 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
2138 		if (ATH_TXQ_SETUP(sc, i) && (qcumask & (1 << i)))
2139 			ath_tx_processq(sc, &sc->tx.txq[i]);
2140 	}
2141 }
2142 
2143 void ath_tx_edma_tasklet(struct ath_softc *sc)
2144 {
2145 	struct ath_tx_status txs;
2146 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2147 	struct ath_hw *ah = sc->sc_ah;
2148 	struct ath_txq *txq;
2149 	struct ath_buf *bf, *lastbf;
2150 	struct list_head bf_head;
2151 	int status;
2152 	int txok;
2153 	int qnum;
2154 
2155 	for (;;) {
2156 		status = ath9k_hw_txprocdesc(ah, NULL, (void *)&txs);
2157 		if (status == -EINPROGRESS)
2158 			break;
2159 		if (status == -EIO) {
2160 			ath_dbg(common, ATH_DBG_XMIT,
2161 				"Error processing tx status\n");
2162 			break;
2163 		}
2164 
2165 		/* Skip beacon completions */
2166 		if (txs.qid == sc->beacon.beaconq)
2167 			continue;
2168 
2169 		txq = &sc->tx.txq[txs.qid];
2170 
2171 		spin_lock_bh(&txq->axq_lock);
2172 		if (list_empty(&txq->txq_fifo[txq->txq_tailidx])) {
2173 			spin_unlock_bh(&txq->axq_lock);
2174 			return;
2175 		}
2176 
2177 		bf = list_first_entry(&txq->txq_fifo[txq->txq_tailidx],
2178 				      struct ath_buf, list);
2179 		lastbf = bf->bf_lastbf;
2180 
2181 		INIT_LIST_HEAD(&bf_head);
2182 		list_cut_position(&bf_head, &txq->txq_fifo[txq->txq_tailidx],
2183 				  &lastbf->list);
2184 		INCR(txq->txq_tailidx, ATH_TXFIFO_DEPTH);
2185 		txq->axq_depth--;
2186 		txq->axq_tx_inprogress = false;
2187 		if (bf_is_ampdu_not_probing(bf))
2188 			txq->axq_ampdu_depth--;
2189 		spin_unlock_bh(&txq->axq_lock);
2190 
2191 		txok = !(txs.ts_status & ATH9K_TXERR_MASK);
2192 
2193 		if (!bf_isampdu(bf)) {
2194 			if (txs.ts_status & ATH9K_TXERR_XRETRY)
2195 				bf->bf_state.bf_type |= BUF_XRETRY;
2196 			ath_tx_rc_status(bf, &txs, 1, txok ? 0 : 1, txok, true);
2197 		}
2198 
2199 		qnum = skb_get_queue_mapping(bf->bf_mpdu);
2200 
2201 		if (bf_isampdu(bf))
2202 			ath_tx_complete_aggr(sc, txq, bf, &bf_head, &txs,
2203 					     txok, true);
2204 		else
2205 			ath_tx_complete_buf(sc, bf, txq, &bf_head,
2206 					    &txs, txok, 0);
2207 
2208 		if (txq == sc->tx.txq_map[qnum])
2209 			ath_wake_mac80211_queue(sc, qnum);
2210 
2211 		spin_lock_bh(&txq->axq_lock);
2212 		if (!list_empty(&txq->txq_fifo_pending)) {
2213 			INIT_LIST_HEAD(&bf_head);
2214 			bf = list_first_entry(&txq->txq_fifo_pending,
2215 				struct ath_buf, list);
2216 			list_cut_position(&bf_head, &txq->txq_fifo_pending,
2217 				&bf->bf_lastbf->list);
2218 			ath_tx_txqaddbuf(sc, txq, &bf_head);
2219 		} else if (sc->sc_flags & SC_OP_TXAGGR)
2220 			ath_txq_schedule(sc, txq);
2221 		spin_unlock_bh(&txq->axq_lock);
2222 	}
2223 }
2224 
2225 /*****************/
2226 /* Init, Cleanup */
2227 /*****************/
2228 
2229 static int ath_txstatus_setup(struct ath_softc *sc, int size)
2230 {
2231 	struct ath_descdma *dd = &sc->txsdma;
2232 	u8 txs_len = sc->sc_ah->caps.txs_len;
2233 
2234 	dd->dd_desc_len = size * txs_len;
2235 	dd->dd_desc = dma_alloc_coherent(sc->dev, dd->dd_desc_len,
2236 					 &dd->dd_desc_paddr, GFP_KERNEL);
2237 	if (!dd->dd_desc)
2238 		return -ENOMEM;
2239 
2240 	return 0;
2241 }
2242 
2243 static int ath_tx_edma_init(struct ath_softc *sc)
2244 {
2245 	int err;
2246 
2247 	err = ath_txstatus_setup(sc, ATH_TXSTATUS_RING_SIZE);
2248 	if (!err)
2249 		ath9k_hw_setup_statusring(sc->sc_ah, sc->txsdma.dd_desc,
2250 					  sc->txsdma.dd_desc_paddr,
2251 					  ATH_TXSTATUS_RING_SIZE);
2252 
2253 	return err;
2254 }
2255 
2256 static void ath_tx_edma_cleanup(struct ath_softc *sc)
2257 {
2258 	struct ath_descdma *dd = &sc->txsdma;
2259 
2260 	dma_free_coherent(sc->dev, dd->dd_desc_len, dd->dd_desc,
2261 			  dd->dd_desc_paddr);
2262 }
2263 
2264 int ath_tx_init(struct ath_softc *sc, int nbufs)
2265 {
2266 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2267 	int error = 0;
2268 
2269 	spin_lock_init(&sc->tx.txbuflock);
2270 
2271 	error = ath_descdma_setup(sc, &sc->tx.txdma, &sc->tx.txbuf,
2272 				  "tx", nbufs, 1, 1);
2273 	if (error != 0) {
2274 		ath_err(common,
2275 			"Failed to allocate tx descriptors: %d\n", error);
2276 		goto err;
2277 	}
2278 
2279 	error = ath_descdma_setup(sc, &sc->beacon.bdma, &sc->beacon.bbuf,
2280 				  "beacon", ATH_BCBUF, 1, 1);
2281 	if (error != 0) {
2282 		ath_err(common,
2283 			"Failed to allocate beacon descriptors: %d\n", error);
2284 		goto err;
2285 	}
2286 
2287 	INIT_DELAYED_WORK(&sc->tx_complete_work, ath_tx_complete_poll_work);
2288 
2289 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
2290 		error = ath_tx_edma_init(sc);
2291 		if (error)
2292 			goto err;
2293 	}
2294 
2295 err:
2296 	if (error != 0)
2297 		ath_tx_cleanup(sc);
2298 
2299 	return error;
2300 }
2301 
2302 void ath_tx_cleanup(struct ath_softc *sc)
2303 {
2304 	if (sc->beacon.bdma.dd_desc_len != 0)
2305 		ath_descdma_cleanup(sc, &sc->beacon.bdma, &sc->beacon.bbuf);
2306 
2307 	if (sc->tx.txdma.dd_desc_len != 0)
2308 		ath_descdma_cleanup(sc, &sc->tx.txdma, &sc->tx.txbuf);
2309 
2310 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
2311 		ath_tx_edma_cleanup(sc);
2312 }
2313 
2314 void ath_tx_node_init(struct ath_softc *sc, struct ath_node *an)
2315 {
2316 	struct ath_atx_tid *tid;
2317 	struct ath_atx_ac *ac;
2318 	int tidno, acno;
2319 
2320 	for (tidno = 0, tid = &an->tid[tidno];
2321 	     tidno < WME_NUM_TID;
2322 	     tidno++, tid++) {
2323 		tid->an        = an;
2324 		tid->tidno     = tidno;
2325 		tid->seq_start = tid->seq_next = 0;
2326 		tid->baw_size  = WME_MAX_BA;
2327 		tid->baw_head  = tid->baw_tail = 0;
2328 		tid->sched     = false;
2329 		tid->paused    = false;
2330 		tid->state &= ~AGGR_CLEANUP;
2331 		INIT_LIST_HEAD(&tid->buf_q);
2332 		acno = TID_TO_WME_AC(tidno);
2333 		tid->ac = &an->ac[acno];
2334 		tid->state &= ~AGGR_ADDBA_COMPLETE;
2335 		tid->state &= ~AGGR_ADDBA_PROGRESS;
2336 	}
2337 
2338 	for (acno = 0, ac = &an->ac[acno];
2339 	     acno < WME_NUM_AC; acno++, ac++) {
2340 		ac->sched    = false;
2341 		ac->txq = sc->tx.txq_map[acno];
2342 		INIT_LIST_HEAD(&ac->tid_q);
2343 	}
2344 }
2345 
2346 void ath_tx_node_cleanup(struct ath_softc *sc, struct ath_node *an)
2347 {
2348 	struct ath_atx_ac *ac;
2349 	struct ath_atx_tid *tid;
2350 	struct ath_txq *txq;
2351 	int tidno;
2352 
2353 	for (tidno = 0, tid = &an->tid[tidno];
2354 	     tidno < WME_NUM_TID; tidno++, tid++) {
2355 
2356 		ac = tid->ac;
2357 		txq = ac->txq;
2358 
2359 		spin_lock_bh(&txq->axq_lock);
2360 
2361 		if (tid->sched) {
2362 			list_del(&tid->list);
2363 			tid->sched = false;
2364 		}
2365 
2366 		if (ac->sched) {
2367 			list_del(&ac->list);
2368 			tid->ac->sched = false;
2369 		}
2370 
2371 		ath_tid_drain(sc, txq, tid);
2372 		tid->state &= ~AGGR_ADDBA_COMPLETE;
2373 		tid->state &= ~AGGR_CLEANUP;
2374 
2375 		spin_unlock_bh(&txq->axq_lock);
2376 	}
2377 }
2378