xref: /linux/drivers/net/wireless/ath/ath9k/xmit.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
1 /*
2  * Copyright (c) 2008-2011 Atheros Communications Inc.
3  *
4  * Permission to use, copy, modify, and/or distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <linux/dma-mapping.h>
18 #include "ath9k.h"
19 #include "ar9003_mac.h"
20 
21 #define BITS_PER_BYTE           8
22 #define OFDM_PLCP_BITS          22
23 #define HT_RC_2_STREAMS(_rc)    ((((_rc) & 0x78) >> 3) + 1)
24 #define L_STF                   8
25 #define L_LTF                   8
26 #define L_SIG                   4
27 #define HT_SIG                  8
28 #define HT_STF                  4
29 #define HT_LTF(_ns)             (4 * (_ns))
30 #define SYMBOL_TIME(_ns)        ((_ns) << 2) /* ns * 4 us */
31 #define SYMBOL_TIME_HALFGI(_ns) (((_ns) * 18 + 4) / 5)  /* ns * 3.6 us */
32 #define NUM_SYMBOLS_PER_USEC(_usec) (_usec >> 2)
33 #define NUM_SYMBOLS_PER_USEC_HALFGI(_usec) (((_usec*5)-4)/18)
34 
35 
36 static u16 bits_per_symbol[][2] = {
37 	/* 20MHz 40MHz */
38 	{    26,   54 },     /*  0: BPSK */
39 	{    52,  108 },     /*  1: QPSK 1/2 */
40 	{    78,  162 },     /*  2: QPSK 3/4 */
41 	{   104,  216 },     /*  3: 16-QAM 1/2 */
42 	{   156,  324 },     /*  4: 16-QAM 3/4 */
43 	{   208,  432 },     /*  5: 64-QAM 2/3 */
44 	{   234,  486 },     /*  6: 64-QAM 3/4 */
45 	{   260,  540 },     /*  7: 64-QAM 5/6 */
46 };
47 
48 #define IS_HT_RATE(_rate)     ((_rate) & 0x80)
49 
50 static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
51 			       struct ath_atx_tid *tid, struct sk_buff *skb);
52 static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
53 			    int tx_flags, struct ath_txq *txq);
54 static void ath_tx_complete_buf(struct ath_softc *sc, struct ath_buf *bf,
55 				struct ath_txq *txq, struct list_head *bf_q,
56 				struct ath_tx_status *ts, int txok, int sendbar);
57 static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq,
58 			     struct list_head *head, bool internal);
59 static void ath_tx_rc_status(struct ath_softc *sc, struct ath_buf *bf,
60 			     struct ath_tx_status *ts, int nframes, int nbad,
61 			     int txok);
62 static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
63 			      int seqno);
64 static struct ath_buf *ath_tx_setup_buffer(struct ath_softc *sc,
65 					   struct ath_txq *txq,
66 					   struct ath_atx_tid *tid,
67 					   struct sk_buff *skb);
68 
69 enum {
70 	MCS_HT20,
71 	MCS_HT20_SGI,
72 	MCS_HT40,
73 	MCS_HT40_SGI,
74 };
75 
76 static int ath_max_4ms_framelen[4][32] = {
77 	[MCS_HT20] = {
78 		3212,  6432,  9648,  12864,  19300,  25736,  28952,  32172,
79 		6424,  12852, 19280, 25708,  38568,  51424,  57852,  64280,
80 		9628,  19260, 28896, 38528,  57792,  65532,  65532,  65532,
81 		12828, 25656, 38488, 51320,  65532,  65532,  65532,  65532,
82 	},
83 	[MCS_HT20_SGI] = {
84 		3572,  7144,  10720,  14296,  21444,  28596,  32172,  35744,
85 		7140,  14284, 21428,  28568,  42856,  57144,  64288,  65532,
86 		10700, 21408, 32112,  42816,  64228,  65532,  65532,  65532,
87 		14256, 28516, 42780,  57040,  65532,  65532,  65532,  65532,
88 	},
89 	[MCS_HT40] = {
90 		6680,  13360,  20044,  26724,  40092,  53456,  60140,  65532,
91 		13348, 26700,  40052,  53400,  65532,  65532,  65532,  65532,
92 		20004, 40008,  60016,  65532,  65532,  65532,  65532,  65532,
93 		26644, 53292,  65532,  65532,  65532,  65532,  65532,  65532,
94 	},
95 	[MCS_HT40_SGI] = {
96 		7420,  14844,  22272,  29696,  44544,  59396,  65532,  65532,
97 		14832, 29668,  44504,  59340,  65532,  65532,  65532,  65532,
98 		22232, 44464,  65532,  65532,  65532,  65532,  65532,  65532,
99 		29616, 59232,  65532,  65532,  65532,  65532,  65532,  65532,
100 	}
101 };
102 
103 /*********************/
104 /* Aggregation logic */
105 /*********************/
106 
107 static void ath_tx_queue_tid(struct ath_txq *txq, struct ath_atx_tid *tid)
108 {
109 	struct ath_atx_ac *ac = tid->ac;
110 
111 	if (tid->paused)
112 		return;
113 
114 	if (tid->sched)
115 		return;
116 
117 	tid->sched = true;
118 	list_add_tail(&tid->list, &ac->tid_q);
119 
120 	if (ac->sched)
121 		return;
122 
123 	ac->sched = true;
124 	list_add_tail(&ac->list, &txq->axq_acq);
125 }
126 
127 static void ath_tx_resume_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
128 {
129 	struct ath_txq *txq = tid->ac->txq;
130 
131 	WARN_ON(!tid->paused);
132 
133 	spin_lock_bh(&txq->axq_lock);
134 	tid->paused = false;
135 
136 	if (skb_queue_empty(&tid->buf_q))
137 		goto unlock;
138 
139 	ath_tx_queue_tid(txq, tid);
140 	ath_txq_schedule(sc, txq);
141 unlock:
142 	spin_unlock_bh(&txq->axq_lock);
143 }
144 
145 static struct ath_frame_info *get_frame_info(struct sk_buff *skb)
146 {
147 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
148 	BUILD_BUG_ON(sizeof(struct ath_frame_info) >
149 		     sizeof(tx_info->rate_driver_data));
150 	return (struct ath_frame_info *) &tx_info->rate_driver_data[0];
151 }
152 
153 static void ath_tx_flush_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
154 {
155 	struct ath_txq *txq = tid->ac->txq;
156 	struct sk_buff *skb;
157 	struct ath_buf *bf;
158 	struct list_head bf_head;
159 	struct ath_tx_status ts;
160 	struct ath_frame_info *fi;
161 
162 	INIT_LIST_HEAD(&bf_head);
163 
164 	memset(&ts, 0, sizeof(ts));
165 	spin_lock_bh(&txq->axq_lock);
166 
167 	while ((skb = __skb_dequeue(&tid->buf_q))) {
168 		fi = get_frame_info(skb);
169 		bf = fi->bf;
170 
171 		spin_unlock_bh(&txq->axq_lock);
172 		if (bf && fi->retries) {
173 			list_add_tail(&bf->list, &bf_head);
174 			ath_tx_update_baw(sc, tid, bf->bf_state.seqno);
175 			ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0, 1);
176 		} else {
177 			ath_tx_send_normal(sc, txq, NULL, skb);
178 		}
179 		spin_lock_bh(&txq->axq_lock);
180 	}
181 
182 	spin_unlock_bh(&txq->axq_lock);
183 }
184 
185 static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
186 			      int seqno)
187 {
188 	int index, cindex;
189 
190 	index  = ATH_BA_INDEX(tid->seq_start, seqno);
191 	cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
192 
193 	__clear_bit(cindex, tid->tx_buf);
194 
195 	while (tid->baw_head != tid->baw_tail && !test_bit(tid->baw_head, tid->tx_buf)) {
196 		INCR(tid->seq_start, IEEE80211_SEQ_MAX);
197 		INCR(tid->baw_head, ATH_TID_MAX_BUFS);
198 	}
199 }
200 
201 static void ath_tx_addto_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
202 			     u16 seqno)
203 {
204 	int index, cindex;
205 
206 	index  = ATH_BA_INDEX(tid->seq_start, seqno);
207 	cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
208 	__set_bit(cindex, tid->tx_buf);
209 
210 	if (index >= ((tid->baw_tail - tid->baw_head) &
211 		(ATH_TID_MAX_BUFS - 1))) {
212 		tid->baw_tail = cindex;
213 		INCR(tid->baw_tail, ATH_TID_MAX_BUFS);
214 	}
215 }
216 
217 /*
218  * TODO: For frame(s) that are in the retry state, we will reuse the
219  * sequence number(s) without setting the retry bit. The
220  * alternative is to give up on these and BAR the receiver's window
221  * forward.
222  */
223 static void ath_tid_drain(struct ath_softc *sc, struct ath_txq *txq,
224 			  struct ath_atx_tid *tid)
225 
226 {
227 	struct sk_buff *skb;
228 	struct ath_buf *bf;
229 	struct list_head bf_head;
230 	struct ath_tx_status ts;
231 	struct ath_frame_info *fi;
232 
233 	memset(&ts, 0, sizeof(ts));
234 	INIT_LIST_HEAD(&bf_head);
235 
236 	while ((skb = __skb_dequeue(&tid->buf_q))) {
237 		fi = get_frame_info(skb);
238 		bf = fi->bf;
239 
240 		if (!bf) {
241 			spin_unlock(&txq->axq_lock);
242 			ath_tx_complete(sc, skb, ATH_TX_ERROR, txq);
243 			spin_lock(&txq->axq_lock);
244 			continue;
245 		}
246 
247 		list_add_tail(&bf->list, &bf_head);
248 
249 		if (fi->retries)
250 			ath_tx_update_baw(sc, tid, bf->bf_state.seqno);
251 
252 		spin_unlock(&txq->axq_lock);
253 		ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0, 0);
254 		spin_lock(&txq->axq_lock);
255 	}
256 
257 	tid->seq_next = tid->seq_start;
258 	tid->baw_tail = tid->baw_head;
259 }
260 
261 static void ath_tx_set_retry(struct ath_softc *sc, struct ath_txq *txq,
262 			     struct sk_buff *skb)
263 {
264 	struct ath_frame_info *fi = get_frame_info(skb);
265 	struct ath_buf *bf = fi->bf;
266 	struct ieee80211_hdr *hdr;
267 
268 	TX_STAT_INC(txq->axq_qnum, a_retries);
269 	if (fi->retries++ > 0)
270 		return;
271 
272 	hdr = (struct ieee80211_hdr *)skb->data;
273 	hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_RETRY);
274 	dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
275 		sizeof(*hdr), DMA_TO_DEVICE);
276 }
277 
278 static struct ath_buf *ath_tx_get_buffer(struct ath_softc *sc)
279 {
280 	struct ath_buf *bf = NULL;
281 
282 	spin_lock_bh(&sc->tx.txbuflock);
283 
284 	if (unlikely(list_empty(&sc->tx.txbuf))) {
285 		spin_unlock_bh(&sc->tx.txbuflock);
286 		return NULL;
287 	}
288 
289 	bf = list_first_entry(&sc->tx.txbuf, struct ath_buf, list);
290 	list_del(&bf->list);
291 
292 	spin_unlock_bh(&sc->tx.txbuflock);
293 
294 	return bf;
295 }
296 
297 static void ath_tx_return_buffer(struct ath_softc *sc, struct ath_buf *bf)
298 {
299 	spin_lock_bh(&sc->tx.txbuflock);
300 	list_add_tail(&bf->list, &sc->tx.txbuf);
301 	spin_unlock_bh(&sc->tx.txbuflock);
302 }
303 
304 static struct ath_buf* ath_clone_txbuf(struct ath_softc *sc, struct ath_buf *bf)
305 {
306 	struct ath_buf *tbf;
307 
308 	tbf = ath_tx_get_buffer(sc);
309 	if (WARN_ON(!tbf))
310 		return NULL;
311 
312 	ATH_TXBUF_RESET(tbf);
313 
314 	tbf->bf_mpdu = bf->bf_mpdu;
315 	tbf->bf_buf_addr = bf->bf_buf_addr;
316 	memcpy(tbf->bf_desc, bf->bf_desc, sc->sc_ah->caps.tx_desc_len);
317 	tbf->bf_state = bf->bf_state;
318 
319 	return tbf;
320 }
321 
322 static void ath_tx_count_frames(struct ath_softc *sc, struct ath_buf *bf,
323 			        struct ath_tx_status *ts, int txok,
324 			        int *nframes, int *nbad)
325 {
326 	struct ath_frame_info *fi;
327 	u16 seq_st = 0;
328 	u32 ba[WME_BA_BMP_SIZE >> 5];
329 	int ba_index;
330 	int isaggr = 0;
331 
332 	*nbad = 0;
333 	*nframes = 0;
334 
335 	isaggr = bf_isaggr(bf);
336 	if (isaggr) {
337 		seq_st = ts->ts_seqnum;
338 		memcpy(ba, &ts->ba_low, WME_BA_BMP_SIZE >> 3);
339 	}
340 
341 	while (bf) {
342 		fi = get_frame_info(bf->bf_mpdu);
343 		ba_index = ATH_BA_INDEX(seq_st, bf->bf_state.seqno);
344 
345 		(*nframes)++;
346 		if (!txok || (isaggr && !ATH_BA_ISSET(ba, ba_index)))
347 			(*nbad)++;
348 
349 		bf = bf->bf_next;
350 	}
351 }
352 
353 
354 static void ath_tx_complete_aggr(struct ath_softc *sc, struct ath_txq *txq,
355 				 struct ath_buf *bf, struct list_head *bf_q,
356 				 struct ath_tx_status *ts, int txok, bool retry)
357 {
358 	struct ath_node *an = NULL;
359 	struct sk_buff *skb;
360 	struct ieee80211_sta *sta;
361 	struct ieee80211_hw *hw = sc->hw;
362 	struct ieee80211_hdr *hdr;
363 	struct ieee80211_tx_info *tx_info;
364 	struct ath_atx_tid *tid = NULL;
365 	struct ath_buf *bf_next, *bf_last = bf->bf_lastbf;
366 	struct list_head bf_head;
367 	struct sk_buff_head bf_pending;
368 	u16 seq_st = 0, acked_cnt = 0, txfail_cnt = 0;
369 	u32 ba[WME_BA_BMP_SIZE >> 5];
370 	int isaggr, txfail, txpending, sendbar = 0, needreset = 0, nbad = 0;
371 	bool rc_update = true;
372 	struct ieee80211_tx_rate rates[4];
373 	struct ath_frame_info *fi;
374 	int nframes;
375 	u8 tidno;
376 	bool flush = !!(ts->ts_status & ATH9K_TX_FLUSH);
377 
378 	skb = bf->bf_mpdu;
379 	hdr = (struct ieee80211_hdr *)skb->data;
380 
381 	tx_info = IEEE80211_SKB_CB(skb);
382 
383 	memcpy(rates, tx_info->control.rates, sizeof(rates));
384 
385 	rcu_read_lock();
386 
387 	sta = ieee80211_find_sta_by_ifaddr(hw, hdr->addr1, hdr->addr2);
388 	if (!sta) {
389 		rcu_read_unlock();
390 
391 		INIT_LIST_HEAD(&bf_head);
392 		while (bf) {
393 			bf_next = bf->bf_next;
394 
395 			if (!bf->bf_stale || bf_next != NULL)
396 				list_move_tail(&bf->list, &bf_head);
397 
398 			ath_tx_complete_buf(sc, bf, txq, &bf_head, ts,
399 				0, 0);
400 
401 			bf = bf_next;
402 		}
403 		return;
404 	}
405 
406 	an = (struct ath_node *)sta->drv_priv;
407 	tidno = ieee80211_get_qos_ctl(hdr)[0] & IEEE80211_QOS_CTL_TID_MASK;
408 	tid = ATH_AN_2_TID(an, tidno);
409 
410 	/*
411 	 * The hardware occasionally sends a tx status for the wrong TID.
412 	 * In this case, the BA status cannot be considered valid and all
413 	 * subframes need to be retransmitted
414 	 */
415 	if (tidno != ts->tid)
416 		txok = false;
417 
418 	isaggr = bf_isaggr(bf);
419 	memset(ba, 0, WME_BA_BMP_SIZE >> 3);
420 
421 	if (isaggr && txok) {
422 		if (ts->ts_flags & ATH9K_TX_BA) {
423 			seq_st = ts->ts_seqnum;
424 			memcpy(ba, &ts->ba_low, WME_BA_BMP_SIZE >> 3);
425 		} else {
426 			/*
427 			 * AR5416 can become deaf/mute when BA
428 			 * issue happens. Chip needs to be reset.
429 			 * But AP code may have sychronization issues
430 			 * when perform internal reset in this routine.
431 			 * Only enable reset in STA mode for now.
432 			 */
433 			if (sc->sc_ah->opmode == NL80211_IFTYPE_STATION)
434 				needreset = 1;
435 		}
436 	}
437 
438 	__skb_queue_head_init(&bf_pending);
439 
440 	ath_tx_count_frames(sc, bf, ts, txok, &nframes, &nbad);
441 	while (bf) {
442 		u16 seqno = bf->bf_state.seqno;
443 
444 		txfail = txpending = sendbar = 0;
445 		bf_next = bf->bf_next;
446 
447 		skb = bf->bf_mpdu;
448 		tx_info = IEEE80211_SKB_CB(skb);
449 		fi = get_frame_info(skb);
450 
451 		if (ATH_BA_ISSET(ba, ATH_BA_INDEX(seq_st, seqno))) {
452 			/* transmit completion, subframe is
453 			 * acked by block ack */
454 			acked_cnt++;
455 		} else if (!isaggr && txok) {
456 			/* transmit completion */
457 			acked_cnt++;
458 		} else {
459 			if ((tid->state & AGGR_CLEANUP) || !retry) {
460 				/*
461 				 * cleanup in progress, just fail
462 				 * the un-acked sub-frames
463 				 */
464 				txfail = 1;
465 			} else if (flush) {
466 				txpending = 1;
467 			} else if (fi->retries < ATH_MAX_SW_RETRIES) {
468 				if (txok || !an->sleeping)
469 					ath_tx_set_retry(sc, txq, bf->bf_mpdu);
470 
471 				txpending = 1;
472 			} else {
473 				txfail = 1;
474 				sendbar = 1;
475 				txfail_cnt++;
476 			}
477 		}
478 
479 		/*
480 		 * Make sure the last desc is reclaimed if it
481 		 * not a holding desc.
482 		 */
483 		INIT_LIST_HEAD(&bf_head);
484 		if ((sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) ||
485 		    bf_next != NULL || !bf_last->bf_stale)
486 			list_move_tail(&bf->list, &bf_head);
487 
488 		if (!txpending || (tid->state & AGGR_CLEANUP)) {
489 			/*
490 			 * complete the acked-ones/xretried ones; update
491 			 * block-ack window
492 			 */
493 			spin_lock_bh(&txq->axq_lock);
494 			ath_tx_update_baw(sc, tid, seqno);
495 			spin_unlock_bh(&txq->axq_lock);
496 
497 			if (rc_update && (acked_cnt == 1 || txfail_cnt == 1)) {
498 				memcpy(tx_info->control.rates, rates, sizeof(rates));
499 				ath_tx_rc_status(sc, bf, ts, nframes, nbad, txok);
500 				rc_update = false;
501 			}
502 
503 			ath_tx_complete_buf(sc, bf, txq, &bf_head, ts,
504 				!txfail, sendbar);
505 		} else {
506 			/* retry the un-acked ones */
507 			if (!(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)) {
508 				if (bf->bf_next == NULL && bf_last->bf_stale) {
509 					struct ath_buf *tbf;
510 
511 					tbf = ath_clone_txbuf(sc, bf_last);
512 					/*
513 					 * Update tx baw and complete the
514 					 * frame with failed status if we
515 					 * run out of tx buf.
516 					 */
517 					if (!tbf) {
518 						spin_lock_bh(&txq->axq_lock);
519 						ath_tx_update_baw(sc, tid, seqno);
520 						spin_unlock_bh(&txq->axq_lock);
521 
522 						ath_tx_complete_buf(sc, bf, txq,
523 								    &bf_head,
524 								    ts, 0,
525 								    !flush);
526 						break;
527 					}
528 
529 					fi->bf = tbf;
530 				}
531 			}
532 
533 			/*
534 			 * Put this buffer to the temporary pending
535 			 * queue to retain ordering
536 			 */
537 			__skb_queue_tail(&bf_pending, skb);
538 		}
539 
540 		bf = bf_next;
541 	}
542 
543 	/* prepend un-acked frames to the beginning of the pending frame queue */
544 	if (!skb_queue_empty(&bf_pending)) {
545 		if (an->sleeping)
546 			ieee80211_sta_set_buffered(sta, tid->tidno, true);
547 
548 		spin_lock_bh(&txq->axq_lock);
549 		skb_queue_splice(&bf_pending, &tid->buf_q);
550 		if (!an->sleeping) {
551 			ath_tx_queue_tid(txq, tid);
552 
553 			if (ts->ts_status & ATH9K_TXERR_FILT)
554 				tid->ac->clear_ps_filter = true;
555 		}
556 		spin_unlock_bh(&txq->axq_lock);
557 	}
558 
559 	if (tid->state & AGGR_CLEANUP) {
560 		ath_tx_flush_tid(sc, tid);
561 
562 		if (tid->baw_head == tid->baw_tail) {
563 			tid->state &= ~AGGR_ADDBA_COMPLETE;
564 			tid->state &= ~AGGR_CLEANUP;
565 		}
566 	}
567 
568 	rcu_read_unlock();
569 
570 	if (needreset) {
571 		RESET_STAT_INC(sc, RESET_TYPE_TX_ERROR);
572 		ieee80211_queue_work(sc->hw, &sc->hw_reset_work);
573 	}
574 }
575 
576 static bool ath_lookup_legacy(struct ath_buf *bf)
577 {
578 	struct sk_buff *skb;
579 	struct ieee80211_tx_info *tx_info;
580 	struct ieee80211_tx_rate *rates;
581 	int i;
582 
583 	skb = bf->bf_mpdu;
584 	tx_info = IEEE80211_SKB_CB(skb);
585 	rates = tx_info->control.rates;
586 
587 	for (i = 0; i < 4; i++) {
588 		if (!rates[i].count || rates[i].idx < 0)
589 			break;
590 
591 		if (!(rates[i].flags & IEEE80211_TX_RC_MCS))
592 			return true;
593 	}
594 
595 	return false;
596 }
597 
598 static u32 ath_lookup_rate(struct ath_softc *sc, struct ath_buf *bf,
599 			   struct ath_atx_tid *tid)
600 {
601 	struct sk_buff *skb;
602 	struct ieee80211_tx_info *tx_info;
603 	struct ieee80211_tx_rate *rates;
604 	u32 max_4ms_framelen, frmlen;
605 	u16 aggr_limit, legacy = 0;
606 	int i;
607 
608 	skb = bf->bf_mpdu;
609 	tx_info = IEEE80211_SKB_CB(skb);
610 	rates = tx_info->control.rates;
611 
612 	/*
613 	 * Find the lowest frame length among the rate series that will have a
614 	 * 4ms transmit duration.
615 	 * TODO - TXOP limit needs to be considered.
616 	 */
617 	max_4ms_framelen = ATH_AMPDU_LIMIT_MAX;
618 
619 	for (i = 0; i < 4; i++) {
620 		if (rates[i].count) {
621 			int modeidx;
622 			if (!(rates[i].flags & IEEE80211_TX_RC_MCS)) {
623 				legacy = 1;
624 				break;
625 			}
626 
627 			if (rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
628 				modeidx = MCS_HT40;
629 			else
630 				modeidx = MCS_HT20;
631 
632 			if (rates[i].flags & IEEE80211_TX_RC_SHORT_GI)
633 				modeidx++;
634 
635 			frmlen = ath_max_4ms_framelen[modeidx][rates[i].idx];
636 			max_4ms_framelen = min(max_4ms_framelen, frmlen);
637 		}
638 	}
639 
640 	/*
641 	 * limit aggregate size by the minimum rate if rate selected is
642 	 * not a probe rate, if rate selected is a probe rate then
643 	 * avoid aggregation of this packet.
644 	 */
645 	if (tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE || legacy)
646 		return 0;
647 
648 	if (sc->sc_flags & SC_OP_BT_PRIORITY_DETECTED)
649 		aggr_limit = min((max_4ms_framelen * 3) / 8,
650 				 (u32)ATH_AMPDU_LIMIT_MAX);
651 	else
652 		aggr_limit = min(max_4ms_framelen,
653 				 (u32)ATH_AMPDU_LIMIT_MAX);
654 
655 	/*
656 	 * h/w can accept aggregates up to 16 bit lengths (65535).
657 	 * The IE, however can hold up to 65536, which shows up here
658 	 * as zero. Ignore 65536 since we  are constrained by hw.
659 	 */
660 	if (tid->an->maxampdu)
661 		aggr_limit = min(aggr_limit, tid->an->maxampdu);
662 
663 	return aggr_limit;
664 }
665 
666 /*
667  * Returns the number of delimiters to be added to
668  * meet the minimum required mpdudensity.
669  */
670 static int ath_compute_num_delims(struct ath_softc *sc, struct ath_atx_tid *tid,
671 				  struct ath_buf *bf, u16 frmlen,
672 				  bool first_subfrm)
673 {
674 #define FIRST_DESC_NDELIMS 60
675 	struct sk_buff *skb = bf->bf_mpdu;
676 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
677 	u32 nsymbits, nsymbols;
678 	u16 minlen;
679 	u8 flags, rix;
680 	int width, streams, half_gi, ndelim, mindelim;
681 	struct ath_frame_info *fi = get_frame_info(bf->bf_mpdu);
682 
683 	/* Select standard number of delimiters based on frame length alone */
684 	ndelim = ATH_AGGR_GET_NDELIM(frmlen);
685 
686 	/*
687 	 * If encryption enabled, hardware requires some more padding between
688 	 * subframes.
689 	 * TODO - this could be improved to be dependent on the rate.
690 	 *      The hardware can keep up at lower rates, but not higher rates
691 	 */
692 	if ((fi->keyix != ATH9K_TXKEYIX_INVALID) &&
693 	    !(sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA))
694 		ndelim += ATH_AGGR_ENCRYPTDELIM;
695 
696 	/*
697 	 * Add delimiter when using RTS/CTS with aggregation
698 	 * and non enterprise AR9003 card
699 	 */
700 	if (first_subfrm && !AR_SREV_9580_10_OR_LATER(sc->sc_ah) &&
701 	    (sc->sc_ah->ent_mode & AR_ENT_OTP_MIN_PKT_SIZE_DISABLE))
702 		ndelim = max(ndelim, FIRST_DESC_NDELIMS);
703 
704 	/*
705 	 * Convert desired mpdu density from microeconds to bytes based
706 	 * on highest rate in rate series (i.e. first rate) to determine
707 	 * required minimum length for subframe. Take into account
708 	 * whether high rate is 20 or 40Mhz and half or full GI.
709 	 *
710 	 * If there is no mpdu density restriction, no further calculation
711 	 * is needed.
712 	 */
713 
714 	if (tid->an->mpdudensity == 0)
715 		return ndelim;
716 
717 	rix = tx_info->control.rates[0].idx;
718 	flags = tx_info->control.rates[0].flags;
719 	width = (flags & IEEE80211_TX_RC_40_MHZ_WIDTH) ? 1 : 0;
720 	half_gi = (flags & IEEE80211_TX_RC_SHORT_GI) ? 1 : 0;
721 
722 	if (half_gi)
723 		nsymbols = NUM_SYMBOLS_PER_USEC_HALFGI(tid->an->mpdudensity);
724 	else
725 		nsymbols = NUM_SYMBOLS_PER_USEC(tid->an->mpdudensity);
726 
727 	if (nsymbols == 0)
728 		nsymbols = 1;
729 
730 	streams = HT_RC_2_STREAMS(rix);
731 	nsymbits = bits_per_symbol[rix % 8][width] * streams;
732 	minlen = (nsymbols * nsymbits) / BITS_PER_BYTE;
733 
734 	if (frmlen < minlen) {
735 		mindelim = (minlen - frmlen) / ATH_AGGR_DELIM_SZ;
736 		ndelim = max(mindelim, ndelim);
737 	}
738 
739 	return ndelim;
740 }
741 
742 static enum ATH_AGGR_STATUS ath_tx_form_aggr(struct ath_softc *sc,
743 					     struct ath_txq *txq,
744 					     struct ath_atx_tid *tid,
745 					     struct list_head *bf_q,
746 					     int *aggr_len)
747 {
748 #define PADBYTES(_len) ((4 - ((_len) % 4)) % 4)
749 	struct ath_buf *bf, *bf_first = NULL, *bf_prev = NULL;
750 	int rl = 0, nframes = 0, ndelim, prev_al = 0;
751 	u16 aggr_limit = 0, al = 0, bpad = 0,
752 		al_delta, h_baw = tid->baw_size / 2;
753 	enum ATH_AGGR_STATUS status = ATH_AGGR_DONE;
754 	struct ieee80211_tx_info *tx_info;
755 	struct ath_frame_info *fi;
756 	struct sk_buff *skb;
757 	u16 seqno;
758 
759 	do {
760 		skb = skb_peek(&tid->buf_q);
761 		fi = get_frame_info(skb);
762 		bf = fi->bf;
763 		if (!fi->bf)
764 			bf = ath_tx_setup_buffer(sc, txq, tid, skb);
765 
766 		if (!bf)
767 			continue;
768 
769 		bf->bf_state.bf_type = BUF_AMPDU | BUF_AGGR;
770 		seqno = bf->bf_state.seqno;
771 		if (!bf_first)
772 			bf_first = bf;
773 
774 		/* do not step over block-ack window */
775 		if (!BAW_WITHIN(tid->seq_start, tid->baw_size, seqno)) {
776 			status = ATH_AGGR_BAW_CLOSED;
777 			break;
778 		}
779 
780 		if (!rl) {
781 			aggr_limit = ath_lookup_rate(sc, bf, tid);
782 			rl = 1;
783 		}
784 
785 		/* do not exceed aggregation limit */
786 		al_delta = ATH_AGGR_DELIM_SZ + fi->framelen;
787 
788 		if (nframes &&
789 		    ((aggr_limit < (al + bpad + al_delta + prev_al)) ||
790 		     ath_lookup_legacy(bf))) {
791 			status = ATH_AGGR_LIMITED;
792 			break;
793 		}
794 
795 		tx_info = IEEE80211_SKB_CB(bf->bf_mpdu);
796 		if (nframes && (tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE))
797 			break;
798 
799 		/* do not exceed subframe limit */
800 		if (nframes >= min((int)h_baw, ATH_AMPDU_SUBFRAME_DEFAULT)) {
801 			status = ATH_AGGR_LIMITED;
802 			break;
803 		}
804 
805 		/* add padding for previous frame to aggregation length */
806 		al += bpad + al_delta;
807 
808 		/*
809 		 * Get the delimiters needed to meet the MPDU
810 		 * density for this node.
811 		 */
812 		ndelim = ath_compute_num_delims(sc, tid, bf_first, fi->framelen,
813 						!nframes);
814 		bpad = PADBYTES(al_delta) + (ndelim << 2);
815 
816 		nframes++;
817 		bf->bf_next = NULL;
818 
819 		/* link buffers of this frame to the aggregate */
820 		if (!fi->retries)
821 			ath_tx_addto_baw(sc, tid, seqno);
822 		bf->bf_state.ndelim = ndelim;
823 
824 		__skb_unlink(skb, &tid->buf_q);
825 		list_add_tail(&bf->list, bf_q);
826 		if (bf_prev)
827 			bf_prev->bf_next = bf;
828 
829 		bf_prev = bf;
830 
831 	} while (!skb_queue_empty(&tid->buf_q));
832 
833 	*aggr_len = al;
834 
835 	return status;
836 #undef PADBYTES
837 }
838 
839 /*
840  * rix - rate index
841  * pktlen - total bytes (delims + data + fcs + pads + pad delims)
842  * width  - 0 for 20 MHz, 1 for 40 MHz
843  * half_gi - to use 4us v/s 3.6 us for symbol time
844  */
845 static u32 ath_pkt_duration(struct ath_softc *sc, u8 rix, int pktlen,
846 			    int width, int half_gi, bool shortPreamble)
847 {
848 	u32 nbits, nsymbits, duration, nsymbols;
849 	int streams;
850 
851 	/* find number of symbols: PLCP + data */
852 	streams = HT_RC_2_STREAMS(rix);
853 	nbits = (pktlen << 3) + OFDM_PLCP_BITS;
854 	nsymbits = bits_per_symbol[rix % 8][width] * streams;
855 	nsymbols = (nbits + nsymbits - 1) / nsymbits;
856 
857 	if (!half_gi)
858 		duration = SYMBOL_TIME(nsymbols);
859 	else
860 		duration = SYMBOL_TIME_HALFGI(nsymbols);
861 
862 	/* addup duration for legacy/ht training and signal fields */
863 	duration += L_STF + L_LTF + L_SIG + HT_SIG + HT_STF + HT_LTF(streams);
864 
865 	return duration;
866 }
867 
868 static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf,
869 			     struct ath_tx_info *info, int len)
870 {
871 	struct ath_hw *ah = sc->sc_ah;
872 	struct sk_buff *skb;
873 	struct ieee80211_tx_info *tx_info;
874 	struct ieee80211_tx_rate *rates;
875 	const struct ieee80211_rate *rate;
876 	struct ieee80211_hdr *hdr;
877 	int i;
878 	u8 rix = 0;
879 
880 	skb = bf->bf_mpdu;
881 	tx_info = IEEE80211_SKB_CB(skb);
882 	rates = tx_info->control.rates;
883 	hdr = (struct ieee80211_hdr *)skb->data;
884 
885 	/* set dur_update_en for l-sig computation except for PS-Poll frames */
886 	info->dur_update = !ieee80211_is_pspoll(hdr->frame_control);
887 
888 	/*
889 	 * We check if Short Preamble is needed for the CTS rate by
890 	 * checking the BSS's global flag.
891 	 * But for the rate series, IEEE80211_TX_RC_USE_SHORT_PREAMBLE is used.
892 	 */
893 	rate = ieee80211_get_rts_cts_rate(sc->hw, tx_info);
894 	info->rtscts_rate = rate->hw_value;
895 	if (sc->sc_flags & SC_OP_PREAMBLE_SHORT)
896 		info->rtscts_rate |= rate->hw_value_short;
897 
898 	for (i = 0; i < 4; i++) {
899 		bool is_40, is_sgi, is_sp;
900 		int phy;
901 
902 		if (!rates[i].count || (rates[i].idx < 0))
903 			continue;
904 
905 		rix = rates[i].idx;
906 		info->rates[i].Tries = rates[i].count;
907 
908 		    if (rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) {
909 			info->rates[i].RateFlags |= ATH9K_RATESERIES_RTS_CTS;
910 			info->flags |= ATH9K_TXDESC_RTSENA;
911 		} else if (rates[i].flags & IEEE80211_TX_RC_USE_CTS_PROTECT) {
912 			info->rates[i].RateFlags |= ATH9K_RATESERIES_RTS_CTS;
913 			info->flags |= ATH9K_TXDESC_CTSENA;
914 		}
915 
916 		if (rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
917 			info->rates[i].RateFlags |= ATH9K_RATESERIES_2040;
918 		if (rates[i].flags & IEEE80211_TX_RC_SHORT_GI)
919 			info->rates[i].RateFlags |= ATH9K_RATESERIES_HALFGI;
920 
921 		is_sgi = !!(rates[i].flags & IEEE80211_TX_RC_SHORT_GI);
922 		is_40 = !!(rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH);
923 		is_sp = !!(rates[i].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE);
924 
925 		if (rates[i].flags & IEEE80211_TX_RC_MCS) {
926 			/* MCS rates */
927 			info->rates[i].Rate = rix | 0x80;
928 			info->rates[i].ChSel = ath_txchainmask_reduction(sc,
929 					ah->txchainmask, info->rates[i].Rate);
930 			info->rates[i].PktDuration = ath_pkt_duration(sc, rix, len,
931 				 is_40, is_sgi, is_sp);
932 			if (rix < 8 && (tx_info->flags & IEEE80211_TX_CTL_STBC))
933 				info->rates[i].RateFlags |= ATH9K_RATESERIES_STBC;
934 			continue;
935 		}
936 
937 		/* legacy rates */
938 		if ((tx_info->band == IEEE80211_BAND_2GHZ) &&
939 		    !(rate->flags & IEEE80211_RATE_ERP_G))
940 			phy = WLAN_RC_PHY_CCK;
941 		else
942 			phy = WLAN_RC_PHY_OFDM;
943 
944 		rate = &sc->sbands[tx_info->band].bitrates[rates[i].idx];
945 		info->rates[i].Rate = rate->hw_value;
946 		if (rate->hw_value_short) {
947 			if (rates[i].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
948 				info->rates[i].Rate |= rate->hw_value_short;
949 		} else {
950 			is_sp = false;
951 		}
952 
953 		if (bf->bf_state.bfs_paprd)
954 			info->rates[i].ChSel = ah->txchainmask;
955 		else
956 			info->rates[i].ChSel = ath_txchainmask_reduction(sc,
957 					ah->txchainmask, info->rates[i].Rate);
958 
959 		info->rates[i].PktDuration = ath9k_hw_computetxtime(sc->sc_ah,
960 			phy, rate->bitrate * 100, len, rix, is_sp);
961 	}
962 
963 	/* For AR5416 - RTS cannot be followed by a frame larger than 8K */
964 	if (bf_isaggr(bf) && (len > sc->sc_ah->caps.rts_aggr_limit))
965 		info->flags &= ~ATH9K_TXDESC_RTSENA;
966 
967 	/* ATH9K_TXDESC_RTSENA and ATH9K_TXDESC_CTSENA are mutually exclusive. */
968 	if (info->flags & ATH9K_TXDESC_RTSENA)
969 		info->flags &= ~ATH9K_TXDESC_CTSENA;
970 }
971 
972 static enum ath9k_pkt_type get_hw_packet_type(struct sk_buff *skb)
973 {
974 	struct ieee80211_hdr *hdr;
975 	enum ath9k_pkt_type htype;
976 	__le16 fc;
977 
978 	hdr = (struct ieee80211_hdr *)skb->data;
979 	fc = hdr->frame_control;
980 
981 	if (ieee80211_is_beacon(fc))
982 		htype = ATH9K_PKT_TYPE_BEACON;
983 	else if (ieee80211_is_probe_resp(fc))
984 		htype = ATH9K_PKT_TYPE_PROBE_RESP;
985 	else if (ieee80211_is_atim(fc))
986 		htype = ATH9K_PKT_TYPE_ATIM;
987 	else if (ieee80211_is_pspoll(fc))
988 		htype = ATH9K_PKT_TYPE_PSPOLL;
989 	else
990 		htype = ATH9K_PKT_TYPE_NORMAL;
991 
992 	return htype;
993 }
994 
995 static void ath_tx_fill_desc(struct ath_softc *sc, struct ath_buf *bf,
996 			     struct ath_txq *txq, int len)
997 {
998 	struct ath_hw *ah = sc->sc_ah;
999 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(bf->bf_mpdu);
1000 	struct ath_buf *bf_first = bf;
1001 	struct ath_tx_info info;
1002 	bool aggr = !!(bf->bf_state.bf_type & BUF_AGGR);
1003 
1004 	memset(&info, 0, sizeof(info));
1005 	info.is_first = true;
1006 	info.is_last = true;
1007 	info.txpower = MAX_RATE_POWER;
1008 	info.qcu = txq->axq_qnum;
1009 
1010 	info.flags = ATH9K_TXDESC_INTREQ;
1011 	if (tx_info->flags & IEEE80211_TX_CTL_NO_ACK)
1012 		info.flags |= ATH9K_TXDESC_NOACK;
1013 	if (tx_info->flags & IEEE80211_TX_CTL_LDPC)
1014 		info.flags |= ATH9K_TXDESC_LDPC;
1015 
1016 	ath_buf_set_rate(sc, bf, &info, len);
1017 
1018 	if (tx_info->flags & IEEE80211_TX_CTL_CLEAR_PS_FILT)
1019 		info.flags |= ATH9K_TXDESC_CLRDMASK;
1020 
1021 	if (bf->bf_state.bfs_paprd)
1022 		info.flags |= (u32) bf->bf_state.bfs_paprd << ATH9K_TXDESC_PAPRD_S;
1023 
1024 
1025 	while (bf) {
1026 		struct sk_buff *skb = bf->bf_mpdu;
1027 		struct ath_frame_info *fi = get_frame_info(skb);
1028 
1029 		info.type = get_hw_packet_type(skb);
1030 		if (bf->bf_next)
1031 			info.link = bf->bf_next->bf_daddr;
1032 		else
1033 			info.link = 0;
1034 
1035 		info.buf_addr[0] = bf->bf_buf_addr;
1036 		info.buf_len[0] = skb->len;
1037 		info.pkt_len = fi->framelen;
1038 		info.keyix = fi->keyix;
1039 		info.keytype = fi->keytype;
1040 
1041 		if (aggr) {
1042 			if (bf == bf_first)
1043 				info.aggr = AGGR_BUF_FIRST;
1044 			else if (!bf->bf_next)
1045 				info.aggr = AGGR_BUF_LAST;
1046 			else
1047 				info.aggr = AGGR_BUF_MIDDLE;
1048 
1049 			info.ndelim = bf->bf_state.ndelim;
1050 			info.aggr_len = len;
1051 		}
1052 
1053 		ath9k_hw_set_txdesc(ah, bf->bf_desc, &info);
1054 		bf = bf->bf_next;
1055 	}
1056 }
1057 
1058 static void ath_tx_sched_aggr(struct ath_softc *sc, struct ath_txq *txq,
1059 			      struct ath_atx_tid *tid)
1060 {
1061 	struct ath_buf *bf;
1062 	enum ATH_AGGR_STATUS status;
1063 	struct ieee80211_tx_info *tx_info;
1064 	struct list_head bf_q;
1065 	int aggr_len;
1066 
1067 	do {
1068 		if (skb_queue_empty(&tid->buf_q))
1069 			return;
1070 
1071 		INIT_LIST_HEAD(&bf_q);
1072 
1073 		status = ath_tx_form_aggr(sc, txq, tid, &bf_q, &aggr_len);
1074 
1075 		/*
1076 		 * no frames picked up to be aggregated;
1077 		 * block-ack window is not open.
1078 		 */
1079 		if (list_empty(&bf_q))
1080 			break;
1081 
1082 		bf = list_first_entry(&bf_q, struct ath_buf, list);
1083 		bf->bf_lastbf = list_entry(bf_q.prev, struct ath_buf, list);
1084 		tx_info = IEEE80211_SKB_CB(bf->bf_mpdu);
1085 
1086 		if (tid->ac->clear_ps_filter) {
1087 			tid->ac->clear_ps_filter = false;
1088 			tx_info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1089 		} else {
1090 			tx_info->flags &= ~IEEE80211_TX_CTL_CLEAR_PS_FILT;
1091 		}
1092 
1093 		/* if only one frame, send as non-aggregate */
1094 		if (bf == bf->bf_lastbf) {
1095 			aggr_len = get_frame_info(bf->bf_mpdu)->framelen;
1096 			bf->bf_state.bf_type = BUF_AMPDU;
1097 		} else {
1098 			TX_STAT_INC(txq->axq_qnum, a_aggr);
1099 		}
1100 
1101 		ath_tx_fill_desc(sc, bf, txq, aggr_len);
1102 		ath_tx_txqaddbuf(sc, txq, &bf_q, false);
1103 	} while (txq->axq_ampdu_depth < ATH_AGGR_MIN_QDEPTH &&
1104 		 status != ATH_AGGR_BAW_CLOSED);
1105 }
1106 
1107 int ath_tx_aggr_start(struct ath_softc *sc, struct ieee80211_sta *sta,
1108 		      u16 tid, u16 *ssn)
1109 {
1110 	struct ath_atx_tid *txtid;
1111 	struct ath_node *an;
1112 
1113 	an = (struct ath_node *)sta->drv_priv;
1114 	txtid = ATH_AN_2_TID(an, tid);
1115 
1116 	if (txtid->state & (AGGR_CLEANUP | AGGR_ADDBA_COMPLETE))
1117 		return -EAGAIN;
1118 
1119 	txtid->state |= AGGR_ADDBA_PROGRESS;
1120 	txtid->paused = true;
1121 	*ssn = txtid->seq_start = txtid->seq_next;
1122 
1123 	memset(txtid->tx_buf, 0, sizeof(txtid->tx_buf));
1124 	txtid->baw_head = txtid->baw_tail = 0;
1125 
1126 	return 0;
1127 }
1128 
1129 void ath_tx_aggr_stop(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid)
1130 {
1131 	struct ath_node *an = (struct ath_node *)sta->drv_priv;
1132 	struct ath_atx_tid *txtid = ATH_AN_2_TID(an, tid);
1133 	struct ath_txq *txq = txtid->ac->txq;
1134 
1135 	if (txtid->state & AGGR_CLEANUP)
1136 		return;
1137 
1138 	if (!(txtid->state & AGGR_ADDBA_COMPLETE)) {
1139 		txtid->state &= ~AGGR_ADDBA_PROGRESS;
1140 		return;
1141 	}
1142 
1143 	spin_lock_bh(&txq->axq_lock);
1144 	txtid->paused = true;
1145 
1146 	/*
1147 	 * If frames are still being transmitted for this TID, they will be
1148 	 * cleaned up during tx completion. To prevent race conditions, this
1149 	 * TID can only be reused after all in-progress subframes have been
1150 	 * completed.
1151 	 */
1152 	if (txtid->baw_head != txtid->baw_tail)
1153 		txtid->state |= AGGR_CLEANUP;
1154 	else
1155 		txtid->state &= ~AGGR_ADDBA_COMPLETE;
1156 	spin_unlock_bh(&txq->axq_lock);
1157 
1158 	ath_tx_flush_tid(sc, txtid);
1159 }
1160 
1161 void ath_tx_aggr_sleep(struct ieee80211_sta *sta, struct ath_softc *sc,
1162 		       struct ath_node *an)
1163 {
1164 	struct ath_atx_tid *tid;
1165 	struct ath_atx_ac *ac;
1166 	struct ath_txq *txq;
1167 	bool buffered;
1168 	int tidno;
1169 
1170 	for (tidno = 0, tid = &an->tid[tidno];
1171 	     tidno < WME_NUM_TID; tidno++, tid++) {
1172 
1173 		if (!tid->sched)
1174 			continue;
1175 
1176 		ac = tid->ac;
1177 		txq = ac->txq;
1178 
1179 		spin_lock_bh(&txq->axq_lock);
1180 
1181 		buffered = !skb_queue_empty(&tid->buf_q);
1182 
1183 		tid->sched = false;
1184 		list_del(&tid->list);
1185 
1186 		if (ac->sched) {
1187 			ac->sched = false;
1188 			list_del(&ac->list);
1189 		}
1190 
1191 		spin_unlock_bh(&txq->axq_lock);
1192 
1193 		ieee80211_sta_set_buffered(sta, tidno, buffered);
1194 	}
1195 }
1196 
1197 void ath_tx_aggr_wakeup(struct ath_softc *sc, struct ath_node *an)
1198 {
1199 	struct ath_atx_tid *tid;
1200 	struct ath_atx_ac *ac;
1201 	struct ath_txq *txq;
1202 	int tidno;
1203 
1204 	for (tidno = 0, tid = &an->tid[tidno];
1205 	     tidno < WME_NUM_TID; tidno++, tid++) {
1206 
1207 		ac = tid->ac;
1208 		txq = ac->txq;
1209 
1210 		spin_lock_bh(&txq->axq_lock);
1211 		ac->clear_ps_filter = true;
1212 
1213 		if (!skb_queue_empty(&tid->buf_q) && !tid->paused) {
1214 			ath_tx_queue_tid(txq, tid);
1215 			ath_txq_schedule(sc, txq);
1216 		}
1217 
1218 		spin_unlock_bh(&txq->axq_lock);
1219 	}
1220 }
1221 
1222 void ath_tx_aggr_resume(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid)
1223 {
1224 	struct ath_atx_tid *txtid;
1225 	struct ath_node *an;
1226 
1227 	an = (struct ath_node *)sta->drv_priv;
1228 
1229 	if (sc->sc_flags & SC_OP_TXAGGR) {
1230 		txtid = ATH_AN_2_TID(an, tid);
1231 		txtid->baw_size =
1232 			IEEE80211_MIN_AMPDU_BUF << sta->ht_cap.ampdu_factor;
1233 		txtid->state |= AGGR_ADDBA_COMPLETE;
1234 		txtid->state &= ~AGGR_ADDBA_PROGRESS;
1235 		ath_tx_resume_tid(sc, txtid);
1236 	}
1237 }
1238 
1239 /********************/
1240 /* Queue Management */
1241 /********************/
1242 
1243 static void ath_txq_drain_pending_buffers(struct ath_softc *sc,
1244 					  struct ath_txq *txq)
1245 {
1246 	struct ath_atx_ac *ac, *ac_tmp;
1247 	struct ath_atx_tid *tid, *tid_tmp;
1248 
1249 	list_for_each_entry_safe(ac, ac_tmp, &txq->axq_acq, list) {
1250 		list_del(&ac->list);
1251 		ac->sched = false;
1252 		list_for_each_entry_safe(tid, tid_tmp, &ac->tid_q, list) {
1253 			list_del(&tid->list);
1254 			tid->sched = false;
1255 			ath_tid_drain(sc, txq, tid);
1256 		}
1257 	}
1258 }
1259 
1260 struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype)
1261 {
1262 	struct ath_hw *ah = sc->sc_ah;
1263 	struct ath9k_tx_queue_info qi;
1264 	static const int subtype_txq_to_hwq[] = {
1265 		[WME_AC_BE] = ATH_TXQ_AC_BE,
1266 		[WME_AC_BK] = ATH_TXQ_AC_BK,
1267 		[WME_AC_VI] = ATH_TXQ_AC_VI,
1268 		[WME_AC_VO] = ATH_TXQ_AC_VO,
1269 	};
1270 	int axq_qnum, i;
1271 
1272 	memset(&qi, 0, sizeof(qi));
1273 	qi.tqi_subtype = subtype_txq_to_hwq[subtype];
1274 	qi.tqi_aifs = ATH9K_TXQ_USEDEFAULT;
1275 	qi.tqi_cwmin = ATH9K_TXQ_USEDEFAULT;
1276 	qi.tqi_cwmax = ATH9K_TXQ_USEDEFAULT;
1277 	qi.tqi_physCompBuf = 0;
1278 
1279 	/*
1280 	 * Enable interrupts only for EOL and DESC conditions.
1281 	 * We mark tx descriptors to receive a DESC interrupt
1282 	 * when a tx queue gets deep; otherwise waiting for the
1283 	 * EOL to reap descriptors.  Note that this is done to
1284 	 * reduce interrupt load and this only defers reaping
1285 	 * descriptors, never transmitting frames.  Aside from
1286 	 * reducing interrupts this also permits more concurrency.
1287 	 * The only potential downside is if the tx queue backs
1288 	 * up in which case the top half of the kernel may backup
1289 	 * due to a lack of tx descriptors.
1290 	 *
1291 	 * The UAPSD queue is an exception, since we take a desc-
1292 	 * based intr on the EOSP frames.
1293 	 */
1294 	if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
1295 		qi.tqi_qflags = TXQ_FLAG_TXOKINT_ENABLE |
1296 				TXQ_FLAG_TXERRINT_ENABLE;
1297 	} else {
1298 		if (qtype == ATH9K_TX_QUEUE_UAPSD)
1299 			qi.tqi_qflags = TXQ_FLAG_TXDESCINT_ENABLE;
1300 		else
1301 			qi.tqi_qflags = TXQ_FLAG_TXEOLINT_ENABLE |
1302 					TXQ_FLAG_TXDESCINT_ENABLE;
1303 	}
1304 	axq_qnum = ath9k_hw_setuptxqueue(ah, qtype, &qi);
1305 	if (axq_qnum == -1) {
1306 		/*
1307 		 * NB: don't print a message, this happens
1308 		 * normally on parts with too few tx queues
1309 		 */
1310 		return NULL;
1311 	}
1312 	if (!ATH_TXQ_SETUP(sc, axq_qnum)) {
1313 		struct ath_txq *txq = &sc->tx.txq[axq_qnum];
1314 
1315 		txq->axq_qnum = axq_qnum;
1316 		txq->mac80211_qnum = -1;
1317 		txq->axq_link = NULL;
1318 		INIT_LIST_HEAD(&txq->axq_q);
1319 		INIT_LIST_HEAD(&txq->axq_acq);
1320 		spin_lock_init(&txq->axq_lock);
1321 		txq->axq_depth = 0;
1322 		txq->axq_ampdu_depth = 0;
1323 		txq->axq_tx_inprogress = false;
1324 		sc->tx.txqsetup |= 1<<axq_qnum;
1325 
1326 		txq->txq_headidx = txq->txq_tailidx = 0;
1327 		for (i = 0; i < ATH_TXFIFO_DEPTH; i++)
1328 			INIT_LIST_HEAD(&txq->txq_fifo[i]);
1329 	}
1330 	return &sc->tx.txq[axq_qnum];
1331 }
1332 
1333 int ath_txq_update(struct ath_softc *sc, int qnum,
1334 		   struct ath9k_tx_queue_info *qinfo)
1335 {
1336 	struct ath_hw *ah = sc->sc_ah;
1337 	int error = 0;
1338 	struct ath9k_tx_queue_info qi;
1339 
1340 	if (qnum == sc->beacon.beaconq) {
1341 		/*
1342 		 * XXX: for beacon queue, we just save the parameter.
1343 		 * It will be picked up by ath_beaconq_config when
1344 		 * it's necessary.
1345 		 */
1346 		sc->beacon.beacon_qi = *qinfo;
1347 		return 0;
1348 	}
1349 
1350 	BUG_ON(sc->tx.txq[qnum].axq_qnum != qnum);
1351 
1352 	ath9k_hw_get_txq_props(ah, qnum, &qi);
1353 	qi.tqi_aifs = qinfo->tqi_aifs;
1354 	qi.tqi_cwmin = qinfo->tqi_cwmin;
1355 	qi.tqi_cwmax = qinfo->tqi_cwmax;
1356 	qi.tqi_burstTime = qinfo->tqi_burstTime;
1357 	qi.tqi_readyTime = qinfo->tqi_readyTime;
1358 
1359 	if (!ath9k_hw_set_txq_props(ah, qnum, &qi)) {
1360 		ath_err(ath9k_hw_common(sc->sc_ah),
1361 			"Unable to update hardware queue %u!\n", qnum);
1362 		error = -EIO;
1363 	} else {
1364 		ath9k_hw_resettxqueue(ah, qnum);
1365 	}
1366 
1367 	return error;
1368 }
1369 
1370 int ath_cabq_update(struct ath_softc *sc)
1371 {
1372 	struct ath9k_tx_queue_info qi;
1373 	struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
1374 	int qnum = sc->beacon.cabq->axq_qnum;
1375 
1376 	ath9k_hw_get_txq_props(sc->sc_ah, qnum, &qi);
1377 	/*
1378 	 * Ensure the readytime % is within the bounds.
1379 	 */
1380 	if (sc->config.cabqReadytime < ATH9K_READY_TIME_LO_BOUND)
1381 		sc->config.cabqReadytime = ATH9K_READY_TIME_LO_BOUND;
1382 	else if (sc->config.cabqReadytime > ATH9K_READY_TIME_HI_BOUND)
1383 		sc->config.cabqReadytime = ATH9K_READY_TIME_HI_BOUND;
1384 
1385 	qi.tqi_readyTime = (cur_conf->beacon_interval *
1386 			    sc->config.cabqReadytime) / 100;
1387 	ath_txq_update(sc, qnum, &qi);
1388 
1389 	return 0;
1390 }
1391 
1392 static bool bf_is_ampdu_not_probing(struct ath_buf *bf)
1393 {
1394     struct ieee80211_tx_info *info = IEEE80211_SKB_CB(bf->bf_mpdu);
1395     return bf_isampdu(bf) && !(info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE);
1396 }
1397 
1398 static void ath_drain_txq_list(struct ath_softc *sc, struct ath_txq *txq,
1399 			       struct list_head *list, bool retry_tx)
1400 	__releases(txq->axq_lock)
1401 	__acquires(txq->axq_lock)
1402 {
1403 	struct ath_buf *bf, *lastbf;
1404 	struct list_head bf_head;
1405 	struct ath_tx_status ts;
1406 
1407 	memset(&ts, 0, sizeof(ts));
1408 	ts.ts_status = ATH9K_TX_FLUSH;
1409 	INIT_LIST_HEAD(&bf_head);
1410 
1411 	while (!list_empty(list)) {
1412 		bf = list_first_entry(list, struct ath_buf, list);
1413 
1414 		if (bf->bf_stale) {
1415 			list_del(&bf->list);
1416 
1417 			ath_tx_return_buffer(sc, bf);
1418 			continue;
1419 		}
1420 
1421 		lastbf = bf->bf_lastbf;
1422 		list_cut_position(&bf_head, list, &lastbf->list);
1423 
1424 		txq->axq_depth--;
1425 		if (bf_is_ampdu_not_probing(bf))
1426 			txq->axq_ampdu_depth--;
1427 
1428 		spin_unlock_bh(&txq->axq_lock);
1429 		if (bf_isampdu(bf))
1430 			ath_tx_complete_aggr(sc, txq, bf, &bf_head, &ts, 0,
1431 					     retry_tx);
1432 		else
1433 			ath_tx_complete_buf(sc, bf, txq, &bf_head, &ts, 0, 0);
1434 		spin_lock_bh(&txq->axq_lock);
1435 	}
1436 }
1437 
1438 /*
1439  * Drain a given TX queue (could be Beacon or Data)
1440  *
1441  * This assumes output has been stopped and
1442  * we do not need to block ath_tx_tasklet.
1443  */
1444 void ath_draintxq(struct ath_softc *sc, struct ath_txq *txq, bool retry_tx)
1445 {
1446 	spin_lock_bh(&txq->axq_lock);
1447 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
1448 		int idx = txq->txq_tailidx;
1449 
1450 		while (!list_empty(&txq->txq_fifo[idx])) {
1451 			ath_drain_txq_list(sc, txq, &txq->txq_fifo[idx],
1452 					   retry_tx);
1453 
1454 			INCR(idx, ATH_TXFIFO_DEPTH);
1455 		}
1456 		txq->txq_tailidx = idx;
1457 	}
1458 
1459 	txq->axq_link = NULL;
1460 	txq->axq_tx_inprogress = false;
1461 	ath_drain_txq_list(sc, txq, &txq->axq_q, retry_tx);
1462 
1463 	/* flush any pending frames if aggregation is enabled */
1464 	if ((sc->sc_flags & SC_OP_TXAGGR) && !retry_tx)
1465 		ath_txq_drain_pending_buffers(sc, txq);
1466 
1467 	spin_unlock_bh(&txq->axq_lock);
1468 }
1469 
1470 bool ath_drain_all_txq(struct ath_softc *sc, bool retry_tx)
1471 {
1472 	struct ath_hw *ah = sc->sc_ah;
1473 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1474 	struct ath_txq *txq;
1475 	int i;
1476 	u32 npend = 0;
1477 
1478 	if (sc->sc_flags & SC_OP_INVALID)
1479 		return true;
1480 
1481 	ath9k_hw_abort_tx_dma(ah);
1482 
1483 	/* Check if any queue remains active */
1484 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
1485 		if (!ATH_TXQ_SETUP(sc, i))
1486 			continue;
1487 
1488 		if (ath9k_hw_numtxpending(ah, sc->tx.txq[i].axq_qnum))
1489 			npend |= BIT(i);
1490 	}
1491 
1492 	if (npend)
1493 		ath_err(common, "Failed to stop TX DMA, queues=0x%03x!\n", npend);
1494 
1495 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
1496 		if (!ATH_TXQ_SETUP(sc, i))
1497 			continue;
1498 
1499 		/*
1500 		 * The caller will resume queues with ieee80211_wake_queues.
1501 		 * Mark the queue as not stopped to prevent ath_tx_complete
1502 		 * from waking the queue too early.
1503 		 */
1504 		txq = &sc->tx.txq[i];
1505 		txq->stopped = false;
1506 		ath_draintxq(sc, txq, retry_tx);
1507 	}
1508 
1509 	return !npend;
1510 }
1511 
1512 void ath_tx_cleanupq(struct ath_softc *sc, struct ath_txq *txq)
1513 {
1514 	ath9k_hw_releasetxqueue(sc->sc_ah, txq->axq_qnum);
1515 	sc->tx.txqsetup &= ~(1<<txq->axq_qnum);
1516 }
1517 
1518 /* For each axq_acq entry, for each tid, try to schedule packets
1519  * for transmit until ampdu_depth has reached min Q depth.
1520  */
1521 void ath_txq_schedule(struct ath_softc *sc, struct ath_txq *txq)
1522 {
1523 	struct ath_atx_ac *ac, *ac_tmp, *last_ac;
1524 	struct ath_atx_tid *tid, *last_tid;
1525 
1526 	if (work_pending(&sc->hw_reset_work) || list_empty(&txq->axq_acq) ||
1527 	    txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH)
1528 		return;
1529 
1530 	ac = list_first_entry(&txq->axq_acq, struct ath_atx_ac, list);
1531 	last_ac = list_entry(txq->axq_acq.prev, struct ath_atx_ac, list);
1532 
1533 	list_for_each_entry_safe(ac, ac_tmp, &txq->axq_acq, list) {
1534 		last_tid = list_entry(ac->tid_q.prev, struct ath_atx_tid, list);
1535 		list_del(&ac->list);
1536 		ac->sched = false;
1537 
1538 		while (!list_empty(&ac->tid_q)) {
1539 			tid = list_first_entry(&ac->tid_q, struct ath_atx_tid,
1540 					       list);
1541 			list_del(&tid->list);
1542 			tid->sched = false;
1543 
1544 			if (tid->paused)
1545 				continue;
1546 
1547 			ath_tx_sched_aggr(sc, txq, tid);
1548 
1549 			/*
1550 			 * add tid to round-robin queue if more frames
1551 			 * are pending for the tid
1552 			 */
1553 			if (!skb_queue_empty(&tid->buf_q))
1554 				ath_tx_queue_tid(txq, tid);
1555 
1556 			if (tid == last_tid ||
1557 			    txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH)
1558 				break;
1559 		}
1560 
1561 		if (!list_empty(&ac->tid_q)) {
1562 			if (!ac->sched) {
1563 				ac->sched = true;
1564 				list_add_tail(&ac->list, &txq->axq_acq);
1565 			}
1566 		}
1567 
1568 		if (ac == last_ac ||
1569 		    txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH)
1570 			return;
1571 	}
1572 }
1573 
1574 /***********/
1575 /* TX, DMA */
1576 /***********/
1577 
1578 /*
1579  * Insert a chain of ath_buf (descriptors) on a txq and
1580  * assume the descriptors are already chained together by caller.
1581  */
1582 static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq,
1583 			     struct list_head *head, bool internal)
1584 {
1585 	struct ath_hw *ah = sc->sc_ah;
1586 	struct ath_common *common = ath9k_hw_common(ah);
1587 	struct ath_buf *bf, *bf_last;
1588 	bool puttxbuf = false;
1589 	bool edma;
1590 
1591 	/*
1592 	 * Insert the frame on the outbound list and
1593 	 * pass it on to the hardware.
1594 	 */
1595 
1596 	if (list_empty(head))
1597 		return;
1598 
1599 	edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
1600 	bf = list_first_entry(head, struct ath_buf, list);
1601 	bf_last = list_entry(head->prev, struct ath_buf, list);
1602 
1603 	ath_dbg(common, ATH_DBG_QUEUE,
1604 		"qnum: %d, txq depth: %d\n", txq->axq_qnum, txq->axq_depth);
1605 
1606 	if (edma && list_empty(&txq->txq_fifo[txq->txq_headidx])) {
1607 		list_splice_tail_init(head, &txq->txq_fifo[txq->txq_headidx]);
1608 		INCR(txq->txq_headidx, ATH_TXFIFO_DEPTH);
1609 		puttxbuf = true;
1610 	} else {
1611 		list_splice_tail_init(head, &txq->axq_q);
1612 
1613 		if (txq->axq_link) {
1614 			ath9k_hw_set_desc_link(ah, txq->axq_link, bf->bf_daddr);
1615 			ath_dbg(common, ATH_DBG_XMIT,
1616 				"link[%u] (%p)=%llx (%p)\n",
1617 				txq->axq_qnum, txq->axq_link,
1618 				ito64(bf->bf_daddr), bf->bf_desc);
1619 		} else if (!edma)
1620 			puttxbuf = true;
1621 
1622 		txq->axq_link = bf_last->bf_desc;
1623 	}
1624 
1625 	if (puttxbuf) {
1626 		TX_STAT_INC(txq->axq_qnum, puttxbuf);
1627 		ath9k_hw_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
1628 		ath_dbg(common, ATH_DBG_XMIT, "TXDP[%u] = %llx (%p)\n",
1629 			txq->axq_qnum, ito64(bf->bf_daddr), bf->bf_desc);
1630 	}
1631 
1632 	if (!edma) {
1633 		TX_STAT_INC(txq->axq_qnum, txstart);
1634 		ath9k_hw_txstart(ah, txq->axq_qnum);
1635 	}
1636 
1637 	if (!internal) {
1638 		txq->axq_depth++;
1639 		if (bf_is_ampdu_not_probing(bf))
1640 			txq->axq_ampdu_depth++;
1641 	}
1642 }
1643 
1644 static void ath_tx_send_ampdu(struct ath_softc *sc, struct ath_atx_tid *tid,
1645 			      struct sk_buff *skb, struct ath_tx_control *txctl)
1646 {
1647 	struct ath_frame_info *fi = get_frame_info(skb);
1648 	struct list_head bf_head;
1649 	struct ath_buf *bf;
1650 
1651 	/*
1652 	 * Do not queue to h/w when any of the following conditions is true:
1653 	 * - there are pending frames in software queue
1654 	 * - the TID is currently paused for ADDBA/BAR request
1655 	 * - seqno is not within block-ack window
1656 	 * - h/w queue depth exceeds low water mark
1657 	 */
1658 	if (!skb_queue_empty(&tid->buf_q) || tid->paused ||
1659 	    !BAW_WITHIN(tid->seq_start, tid->baw_size, tid->seq_next) ||
1660 	    txctl->txq->axq_ampdu_depth >= ATH_AGGR_MIN_QDEPTH) {
1661 		/*
1662 		 * Add this frame to software queue for scheduling later
1663 		 * for aggregation.
1664 		 */
1665 		TX_STAT_INC(txctl->txq->axq_qnum, a_queued_sw);
1666 		__skb_queue_tail(&tid->buf_q, skb);
1667 		if (!txctl->an || !txctl->an->sleeping)
1668 			ath_tx_queue_tid(txctl->txq, tid);
1669 		return;
1670 	}
1671 
1672 	bf = ath_tx_setup_buffer(sc, txctl->txq, tid, skb);
1673 	if (!bf)
1674 		return;
1675 
1676 	bf->bf_state.bf_type = BUF_AMPDU;
1677 	INIT_LIST_HEAD(&bf_head);
1678 	list_add(&bf->list, &bf_head);
1679 
1680 	/* Add sub-frame to BAW */
1681 	ath_tx_addto_baw(sc, tid, bf->bf_state.seqno);
1682 
1683 	/* Queue to h/w without aggregation */
1684 	TX_STAT_INC(txctl->txq->axq_qnum, a_queued_hw);
1685 	bf->bf_lastbf = bf;
1686 	ath_tx_fill_desc(sc, bf, txctl->txq, fi->framelen);
1687 	ath_tx_txqaddbuf(sc, txctl->txq, &bf_head, false);
1688 }
1689 
1690 static void ath_tx_send_normal(struct ath_softc *sc, struct ath_txq *txq,
1691 			       struct ath_atx_tid *tid, struct sk_buff *skb)
1692 {
1693 	struct ath_frame_info *fi = get_frame_info(skb);
1694 	struct list_head bf_head;
1695 	struct ath_buf *bf;
1696 
1697 	bf = fi->bf;
1698 	if (!bf)
1699 		bf = ath_tx_setup_buffer(sc, txq, tid, skb);
1700 
1701 	if (!bf)
1702 		return;
1703 
1704 	INIT_LIST_HEAD(&bf_head);
1705 	list_add_tail(&bf->list, &bf_head);
1706 	bf->bf_state.bf_type = 0;
1707 
1708 	/* update starting sequence number for subsequent ADDBA request */
1709 	if (tid)
1710 		INCR(tid->seq_start, IEEE80211_SEQ_MAX);
1711 
1712 	bf->bf_lastbf = bf;
1713 	ath_tx_fill_desc(sc, bf, txq, fi->framelen);
1714 	ath_tx_txqaddbuf(sc, txq, &bf_head, false);
1715 	TX_STAT_INC(txq->axq_qnum, queued);
1716 }
1717 
1718 static void setup_frame_info(struct ieee80211_hw *hw, struct sk_buff *skb,
1719 			     int framelen)
1720 {
1721 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1722 	struct ieee80211_sta *sta = tx_info->control.sta;
1723 	struct ieee80211_key_conf *hw_key = tx_info->control.hw_key;
1724 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1725 	struct ath_frame_info *fi = get_frame_info(skb);
1726 	struct ath_node *an = NULL;
1727 	enum ath9k_key_type keytype;
1728 
1729 	keytype = ath9k_cmn_get_hw_crypto_keytype(skb);
1730 
1731 	if (sta)
1732 		an = (struct ath_node *) sta->drv_priv;
1733 
1734 	memset(fi, 0, sizeof(*fi));
1735 	if (hw_key)
1736 		fi->keyix = hw_key->hw_key_idx;
1737 	else if (an && ieee80211_is_data(hdr->frame_control) && an->ps_key > 0)
1738 		fi->keyix = an->ps_key;
1739 	else
1740 		fi->keyix = ATH9K_TXKEYIX_INVALID;
1741 	fi->keytype = keytype;
1742 	fi->framelen = framelen;
1743 }
1744 
1745 u8 ath_txchainmask_reduction(struct ath_softc *sc, u8 chainmask, u32 rate)
1746 {
1747 	struct ath_hw *ah = sc->sc_ah;
1748 	struct ath9k_channel *curchan = ah->curchan;
1749 	if ((ah->caps.hw_caps & ATH9K_HW_CAP_APM) &&
1750 	    (curchan->channelFlags & CHANNEL_5GHZ) &&
1751 	    (chainmask == 0x7) && (rate < 0x90))
1752 		return 0x3;
1753 	else
1754 		return chainmask;
1755 }
1756 
1757 /*
1758  * Assign a descriptor (and sequence number if necessary,
1759  * and map buffer for DMA. Frees skb on error
1760  */
1761 static struct ath_buf *ath_tx_setup_buffer(struct ath_softc *sc,
1762 					   struct ath_txq *txq,
1763 					   struct ath_atx_tid *tid,
1764 					   struct sk_buff *skb)
1765 {
1766 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1767 	struct ath_frame_info *fi = get_frame_info(skb);
1768 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1769 	struct ath_buf *bf;
1770 	u16 seqno;
1771 
1772 	bf = ath_tx_get_buffer(sc);
1773 	if (!bf) {
1774 		ath_dbg(common, ATH_DBG_XMIT, "TX buffers are full\n");
1775 		goto error;
1776 	}
1777 
1778 	ATH_TXBUF_RESET(bf);
1779 
1780 	if (tid) {
1781 		seqno = tid->seq_next;
1782 		hdr->seq_ctrl = cpu_to_le16(tid->seq_next << IEEE80211_SEQ_SEQ_SHIFT);
1783 		INCR(tid->seq_next, IEEE80211_SEQ_MAX);
1784 		bf->bf_state.seqno = seqno;
1785 	}
1786 
1787 	bf->bf_mpdu = skb;
1788 
1789 	bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
1790 					 skb->len, DMA_TO_DEVICE);
1791 	if (unlikely(dma_mapping_error(sc->dev, bf->bf_buf_addr))) {
1792 		bf->bf_mpdu = NULL;
1793 		bf->bf_buf_addr = 0;
1794 		ath_err(ath9k_hw_common(sc->sc_ah),
1795 			"dma_mapping_error() on TX\n");
1796 		ath_tx_return_buffer(sc, bf);
1797 		goto error;
1798 	}
1799 
1800 	fi->bf = bf;
1801 
1802 	return bf;
1803 
1804 error:
1805 	dev_kfree_skb_any(skb);
1806 	return NULL;
1807 }
1808 
1809 /* FIXME: tx power */
1810 static void ath_tx_start_dma(struct ath_softc *sc, struct sk_buff *skb,
1811 			     struct ath_tx_control *txctl)
1812 {
1813 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1814 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1815 	struct ath_atx_tid *tid = NULL;
1816 	struct ath_buf *bf;
1817 	u8 tidno;
1818 
1819 	spin_lock_bh(&txctl->txq->axq_lock);
1820 	if ((sc->sc_flags & SC_OP_TXAGGR) && txctl->an &&
1821 		ieee80211_is_data_qos(hdr->frame_control)) {
1822 		tidno = ieee80211_get_qos_ctl(hdr)[0] &
1823 			IEEE80211_QOS_CTL_TID_MASK;
1824 		tid = ATH_AN_2_TID(txctl->an, tidno);
1825 
1826 		WARN_ON(tid->ac->txq != txctl->txq);
1827 	}
1828 
1829 	if ((tx_info->flags & IEEE80211_TX_CTL_AMPDU) && tid) {
1830 		/*
1831 		 * Try aggregation if it's a unicast data frame
1832 		 * and the destination is HT capable.
1833 		 */
1834 		ath_tx_send_ampdu(sc, tid, skb, txctl);
1835 	} else {
1836 		bf = ath_tx_setup_buffer(sc, txctl->txq, tid, skb);
1837 		if (!bf)
1838 			goto out;
1839 
1840 		bf->bf_state.bfs_paprd = txctl->paprd;
1841 
1842 		if (txctl->paprd)
1843 			bf->bf_state.bfs_paprd_timestamp = jiffies;
1844 
1845 		ath_tx_send_normal(sc, txctl->txq, tid, skb);
1846 	}
1847 
1848 out:
1849 	spin_unlock_bh(&txctl->txq->axq_lock);
1850 }
1851 
1852 /* Upon failure caller should free skb */
1853 int ath_tx_start(struct ieee80211_hw *hw, struct sk_buff *skb,
1854 		 struct ath_tx_control *txctl)
1855 {
1856 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
1857 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
1858 	struct ieee80211_sta *sta = info->control.sta;
1859 	struct ieee80211_vif *vif = info->control.vif;
1860 	struct ath_softc *sc = hw->priv;
1861 	struct ath_txq *txq = txctl->txq;
1862 	int padpos, padsize;
1863 	int frmlen = skb->len + FCS_LEN;
1864 	int q;
1865 
1866 	/* NOTE:  sta can be NULL according to net/mac80211.h */
1867 	if (sta)
1868 		txctl->an = (struct ath_node *)sta->drv_priv;
1869 
1870 	if (info->control.hw_key)
1871 		frmlen += info->control.hw_key->icv_len;
1872 
1873 	/*
1874 	 * As a temporary workaround, assign seq# here; this will likely need
1875 	 * to be cleaned up to work better with Beacon transmission and virtual
1876 	 * BSSes.
1877 	 */
1878 	if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
1879 		if (info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)
1880 			sc->tx.seq_no += 0x10;
1881 		hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
1882 		hdr->seq_ctrl |= cpu_to_le16(sc->tx.seq_no);
1883 	}
1884 
1885 	/* Add the padding after the header if this is not already done */
1886 	padpos = ath9k_cmn_padpos(hdr->frame_control);
1887 	padsize = padpos & 3;
1888 	if (padsize && skb->len > padpos) {
1889 		if (skb_headroom(skb) < padsize)
1890 			return -ENOMEM;
1891 
1892 		skb_push(skb, padsize);
1893 		memmove(skb->data, skb->data + padsize, padpos);
1894 		hdr = (struct ieee80211_hdr *) skb->data;
1895 	}
1896 
1897 	if ((vif && vif->type != NL80211_IFTYPE_AP &&
1898 	            vif->type != NL80211_IFTYPE_AP_VLAN) ||
1899 	    !ieee80211_is_data(hdr->frame_control))
1900 		info->flags |= IEEE80211_TX_CTL_CLEAR_PS_FILT;
1901 
1902 	setup_frame_info(hw, skb, frmlen);
1903 
1904 	/*
1905 	 * At this point, the vif, hw_key and sta pointers in the tx control
1906 	 * info are no longer valid (overwritten by the ath_frame_info data.
1907 	 */
1908 
1909 	q = skb_get_queue_mapping(skb);
1910 	spin_lock_bh(&txq->axq_lock);
1911 	if (txq == sc->tx.txq_map[q] &&
1912 	    ++txq->pending_frames > ATH_MAX_QDEPTH && !txq->stopped) {
1913 		ieee80211_stop_queue(sc->hw, q);
1914 		txq->stopped = 1;
1915 	}
1916 	spin_unlock_bh(&txq->axq_lock);
1917 
1918 	ath_tx_start_dma(sc, skb, txctl);
1919 	return 0;
1920 }
1921 
1922 /*****************/
1923 /* TX Completion */
1924 /*****************/
1925 
1926 static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
1927 			    int tx_flags, struct ath_txq *txq)
1928 {
1929 	struct ieee80211_hw *hw = sc->hw;
1930 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1931 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
1932 	struct ieee80211_hdr * hdr = (struct ieee80211_hdr *)skb->data;
1933 	int q, padpos, padsize;
1934 
1935 	ath_dbg(common, ATH_DBG_XMIT, "TX complete: skb: %p\n", skb);
1936 
1937 	if (tx_flags & ATH_TX_BAR)
1938 		tx_info->flags |= IEEE80211_TX_STAT_AMPDU_NO_BACK;
1939 
1940 	if (!(tx_flags & ATH_TX_ERROR))
1941 		/* Frame was ACKed */
1942 		tx_info->flags |= IEEE80211_TX_STAT_ACK;
1943 
1944 	padpos = ath9k_cmn_padpos(hdr->frame_control);
1945 	padsize = padpos & 3;
1946 	if (padsize && skb->len>padpos+padsize) {
1947 		/*
1948 		 * Remove MAC header padding before giving the frame back to
1949 		 * mac80211.
1950 		 */
1951 		memmove(skb->data + padsize, skb->data, padpos);
1952 		skb_pull(skb, padsize);
1953 	}
1954 
1955 	if (sc->ps_flags & PS_WAIT_FOR_TX_ACK) {
1956 		sc->ps_flags &= ~PS_WAIT_FOR_TX_ACK;
1957 		ath_dbg(common, ATH_DBG_PS,
1958 			"Going back to sleep after having received TX status (0x%lx)\n",
1959 			sc->ps_flags & (PS_WAIT_FOR_BEACON |
1960 					PS_WAIT_FOR_CAB |
1961 					PS_WAIT_FOR_PSPOLL_DATA |
1962 					PS_WAIT_FOR_TX_ACK));
1963 	}
1964 
1965 	q = skb_get_queue_mapping(skb);
1966 	if (txq == sc->tx.txq_map[q]) {
1967 		spin_lock_bh(&txq->axq_lock);
1968 		if (WARN_ON(--txq->pending_frames < 0))
1969 			txq->pending_frames = 0;
1970 
1971 		if (txq->stopped && txq->pending_frames < ATH_MAX_QDEPTH) {
1972 			ieee80211_wake_queue(sc->hw, q);
1973 			txq->stopped = 0;
1974 		}
1975 		spin_unlock_bh(&txq->axq_lock);
1976 	}
1977 
1978 	ieee80211_tx_status(hw, skb);
1979 }
1980 
1981 static void ath_tx_complete_buf(struct ath_softc *sc, struct ath_buf *bf,
1982 				struct ath_txq *txq, struct list_head *bf_q,
1983 				struct ath_tx_status *ts, int txok, int sendbar)
1984 {
1985 	struct sk_buff *skb = bf->bf_mpdu;
1986 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1987 	unsigned long flags;
1988 	int tx_flags = 0;
1989 
1990 	if (sendbar)
1991 		tx_flags = ATH_TX_BAR;
1992 
1993 	if (!txok)
1994 		tx_flags |= ATH_TX_ERROR;
1995 
1996 	if (ts->ts_status & ATH9K_TXERR_FILT)
1997 		tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
1998 
1999 	dma_unmap_single(sc->dev, bf->bf_buf_addr, skb->len, DMA_TO_DEVICE);
2000 	bf->bf_buf_addr = 0;
2001 
2002 	if (bf->bf_state.bfs_paprd) {
2003 		if (time_after(jiffies,
2004 				bf->bf_state.bfs_paprd_timestamp +
2005 				msecs_to_jiffies(ATH_PAPRD_TIMEOUT)))
2006 			dev_kfree_skb_any(skb);
2007 		else
2008 			complete(&sc->paprd_complete);
2009 	} else {
2010 		ath_debug_stat_tx(sc, bf, ts, txq, tx_flags);
2011 		ath_tx_complete(sc, skb, tx_flags, txq);
2012 	}
2013 	/* At this point, skb (bf->bf_mpdu) is consumed...make sure we don't
2014 	 * accidentally reference it later.
2015 	 */
2016 	bf->bf_mpdu = NULL;
2017 
2018 	/*
2019 	 * Return the list of ath_buf of this mpdu to free queue
2020 	 */
2021 	spin_lock_irqsave(&sc->tx.txbuflock, flags);
2022 	list_splice_tail_init(bf_q, &sc->tx.txbuf);
2023 	spin_unlock_irqrestore(&sc->tx.txbuflock, flags);
2024 }
2025 
2026 static void ath_tx_rc_status(struct ath_softc *sc, struct ath_buf *bf,
2027 			     struct ath_tx_status *ts, int nframes, int nbad,
2028 			     int txok)
2029 {
2030 	struct sk_buff *skb = bf->bf_mpdu;
2031 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
2032 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
2033 	struct ieee80211_hw *hw = sc->hw;
2034 	struct ath_hw *ah = sc->sc_ah;
2035 	u8 i, tx_rateindex;
2036 
2037 	if (txok)
2038 		tx_info->status.ack_signal = ts->ts_rssi;
2039 
2040 	tx_rateindex = ts->ts_rateindex;
2041 	WARN_ON(tx_rateindex >= hw->max_rates);
2042 
2043 	if (tx_info->flags & IEEE80211_TX_CTL_AMPDU) {
2044 		tx_info->flags |= IEEE80211_TX_STAT_AMPDU;
2045 
2046 		BUG_ON(nbad > nframes);
2047 	}
2048 	tx_info->status.ampdu_len = nframes;
2049 	tx_info->status.ampdu_ack_len = nframes - nbad;
2050 
2051 	if ((ts->ts_status & ATH9K_TXERR_FILT) == 0 &&
2052 	    (tx_info->flags & IEEE80211_TX_CTL_NO_ACK) == 0) {
2053 		/*
2054 		 * If an underrun error is seen assume it as an excessive
2055 		 * retry only if max frame trigger level has been reached
2056 		 * (2 KB for single stream, and 4 KB for dual stream).
2057 		 * Adjust the long retry as if the frame was tried
2058 		 * hw->max_rate_tries times to affect how rate control updates
2059 		 * PER for the failed rate.
2060 		 * In case of congestion on the bus penalizing this type of
2061 		 * underruns should help hardware actually transmit new frames
2062 		 * successfully by eventually preferring slower rates.
2063 		 * This itself should also alleviate congestion on the bus.
2064 		 */
2065 		if (unlikely(ts->ts_flags & (ATH9K_TX_DATA_UNDERRUN |
2066 		                             ATH9K_TX_DELIM_UNDERRUN)) &&
2067 		    ieee80211_is_data(hdr->frame_control) &&
2068 		    ah->tx_trig_level >= sc->sc_ah->config.max_txtrig_level)
2069 			tx_info->status.rates[tx_rateindex].count =
2070 				hw->max_rate_tries;
2071 	}
2072 
2073 	for (i = tx_rateindex + 1; i < hw->max_rates; i++) {
2074 		tx_info->status.rates[i].count = 0;
2075 		tx_info->status.rates[i].idx = -1;
2076 	}
2077 
2078 	tx_info->status.rates[tx_rateindex].count = ts->ts_longretry + 1;
2079 }
2080 
2081 static void ath_tx_process_buffer(struct ath_softc *sc, struct ath_txq *txq,
2082 				  struct ath_tx_status *ts, struct ath_buf *bf,
2083 				  struct list_head *bf_head)
2084 	__releases(txq->axq_lock)
2085 	__acquires(txq->axq_lock)
2086 {
2087 	int txok;
2088 
2089 	txq->axq_depth--;
2090 	txok = !(ts->ts_status & ATH9K_TXERR_MASK);
2091 	txq->axq_tx_inprogress = false;
2092 	if (bf_is_ampdu_not_probing(bf))
2093 		txq->axq_ampdu_depth--;
2094 
2095 	spin_unlock_bh(&txq->axq_lock);
2096 
2097 	if (!bf_isampdu(bf)) {
2098 		ath_tx_rc_status(sc, bf, ts, 1, txok ? 0 : 1, txok);
2099 		ath_tx_complete_buf(sc, bf, txq, bf_head, ts, txok, 0);
2100 	} else
2101 		ath_tx_complete_aggr(sc, txq, bf, bf_head, ts, txok, true);
2102 
2103 	spin_lock_bh(&txq->axq_lock);
2104 
2105 	if (sc->sc_flags & SC_OP_TXAGGR)
2106 		ath_txq_schedule(sc, txq);
2107 }
2108 
2109 static void ath_tx_processq(struct ath_softc *sc, struct ath_txq *txq)
2110 {
2111 	struct ath_hw *ah = sc->sc_ah;
2112 	struct ath_common *common = ath9k_hw_common(ah);
2113 	struct ath_buf *bf, *lastbf, *bf_held = NULL;
2114 	struct list_head bf_head;
2115 	struct ath_desc *ds;
2116 	struct ath_tx_status ts;
2117 	int status;
2118 
2119 	ath_dbg(common, ATH_DBG_QUEUE, "tx queue %d (%x), link %p\n",
2120 		txq->axq_qnum, ath9k_hw_gettxbuf(sc->sc_ah, txq->axq_qnum),
2121 		txq->axq_link);
2122 
2123 	spin_lock_bh(&txq->axq_lock);
2124 	for (;;) {
2125 		if (work_pending(&sc->hw_reset_work))
2126 			break;
2127 
2128 		if (list_empty(&txq->axq_q)) {
2129 			txq->axq_link = NULL;
2130 			if (sc->sc_flags & SC_OP_TXAGGR)
2131 				ath_txq_schedule(sc, txq);
2132 			break;
2133 		}
2134 		bf = list_first_entry(&txq->axq_q, struct ath_buf, list);
2135 
2136 		/*
2137 		 * There is a race condition that a BH gets scheduled
2138 		 * after sw writes TxE and before hw re-load the last
2139 		 * descriptor to get the newly chained one.
2140 		 * Software must keep the last DONE descriptor as a
2141 		 * holding descriptor - software does so by marking
2142 		 * it with the STALE flag.
2143 		 */
2144 		bf_held = NULL;
2145 		if (bf->bf_stale) {
2146 			bf_held = bf;
2147 			if (list_is_last(&bf_held->list, &txq->axq_q))
2148 				break;
2149 
2150 			bf = list_entry(bf_held->list.next, struct ath_buf,
2151 					list);
2152 		}
2153 
2154 		lastbf = bf->bf_lastbf;
2155 		ds = lastbf->bf_desc;
2156 
2157 		memset(&ts, 0, sizeof(ts));
2158 		status = ath9k_hw_txprocdesc(ah, ds, &ts);
2159 		if (status == -EINPROGRESS)
2160 			break;
2161 
2162 		TX_STAT_INC(txq->axq_qnum, txprocdesc);
2163 
2164 		/*
2165 		 * Remove ath_buf's of the same transmit unit from txq,
2166 		 * however leave the last descriptor back as the holding
2167 		 * descriptor for hw.
2168 		 */
2169 		lastbf->bf_stale = true;
2170 		INIT_LIST_HEAD(&bf_head);
2171 		if (!list_is_singular(&lastbf->list))
2172 			list_cut_position(&bf_head,
2173 				&txq->axq_q, lastbf->list.prev);
2174 
2175 		if (bf_held) {
2176 			list_del(&bf_held->list);
2177 			ath_tx_return_buffer(sc, bf_held);
2178 		}
2179 
2180 		ath_tx_process_buffer(sc, txq, &ts, bf, &bf_head);
2181 	}
2182 	spin_unlock_bh(&txq->axq_lock);
2183 }
2184 
2185 static void ath_tx_complete_poll_work(struct work_struct *work)
2186 {
2187 	struct ath_softc *sc = container_of(work, struct ath_softc,
2188 			tx_complete_work.work);
2189 	struct ath_txq *txq;
2190 	int i;
2191 	bool needreset = false;
2192 #ifdef CONFIG_ATH9K_DEBUGFS
2193 	sc->tx_complete_poll_work_seen++;
2194 #endif
2195 
2196 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++)
2197 		if (ATH_TXQ_SETUP(sc, i)) {
2198 			txq = &sc->tx.txq[i];
2199 			spin_lock_bh(&txq->axq_lock);
2200 			if (txq->axq_depth) {
2201 				if (txq->axq_tx_inprogress) {
2202 					needreset = true;
2203 					spin_unlock_bh(&txq->axq_lock);
2204 					break;
2205 				} else {
2206 					txq->axq_tx_inprogress = true;
2207 				}
2208 			}
2209 			spin_unlock_bh(&txq->axq_lock);
2210 		}
2211 
2212 	if (needreset) {
2213 		ath_dbg(ath9k_hw_common(sc->sc_ah), ATH_DBG_RESET,
2214 			"tx hung, resetting the chip\n");
2215 		RESET_STAT_INC(sc, RESET_TYPE_TX_HANG);
2216 		ieee80211_queue_work(sc->hw, &sc->hw_reset_work);
2217 	}
2218 
2219 	ieee80211_queue_delayed_work(sc->hw, &sc->tx_complete_work,
2220 			msecs_to_jiffies(ATH_TX_COMPLETE_POLL_INT));
2221 }
2222 
2223 
2224 
2225 void ath_tx_tasklet(struct ath_softc *sc)
2226 {
2227 	int i;
2228 	u32 qcumask = ((1 << ATH9K_NUM_TX_QUEUES) - 1);
2229 
2230 	ath9k_hw_gettxintrtxqs(sc->sc_ah, &qcumask);
2231 
2232 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
2233 		if (ATH_TXQ_SETUP(sc, i) && (qcumask & (1 << i)))
2234 			ath_tx_processq(sc, &sc->tx.txq[i]);
2235 	}
2236 }
2237 
2238 void ath_tx_edma_tasklet(struct ath_softc *sc)
2239 {
2240 	struct ath_tx_status ts;
2241 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2242 	struct ath_hw *ah = sc->sc_ah;
2243 	struct ath_txq *txq;
2244 	struct ath_buf *bf, *lastbf;
2245 	struct list_head bf_head;
2246 	int status;
2247 
2248 	for (;;) {
2249 		if (work_pending(&sc->hw_reset_work))
2250 			break;
2251 
2252 		status = ath9k_hw_txprocdesc(ah, NULL, (void *)&ts);
2253 		if (status == -EINPROGRESS)
2254 			break;
2255 		if (status == -EIO) {
2256 			ath_dbg(common, ATH_DBG_XMIT,
2257 				"Error processing tx status\n");
2258 			break;
2259 		}
2260 
2261 		/* Skip beacon completions */
2262 		if (ts.qid == sc->beacon.beaconq)
2263 			continue;
2264 
2265 		txq = &sc->tx.txq[ts.qid];
2266 
2267 		spin_lock_bh(&txq->axq_lock);
2268 
2269 		if (list_empty(&txq->txq_fifo[txq->txq_tailidx])) {
2270 			spin_unlock_bh(&txq->axq_lock);
2271 			return;
2272 		}
2273 
2274 		bf = list_first_entry(&txq->txq_fifo[txq->txq_tailidx],
2275 				      struct ath_buf, list);
2276 		lastbf = bf->bf_lastbf;
2277 
2278 		INIT_LIST_HEAD(&bf_head);
2279 		list_cut_position(&bf_head, &txq->txq_fifo[txq->txq_tailidx],
2280 				  &lastbf->list);
2281 
2282 		if (list_empty(&txq->txq_fifo[txq->txq_tailidx])) {
2283 			INCR(txq->txq_tailidx, ATH_TXFIFO_DEPTH);
2284 
2285 			if (!list_empty(&txq->axq_q)) {
2286 				struct list_head bf_q;
2287 
2288 				INIT_LIST_HEAD(&bf_q);
2289 				txq->axq_link = NULL;
2290 				list_splice_tail_init(&txq->axq_q, &bf_q);
2291 				ath_tx_txqaddbuf(sc, txq, &bf_q, true);
2292 			}
2293 		}
2294 
2295 		ath_tx_process_buffer(sc, txq, &ts, bf, &bf_head);
2296 		spin_unlock_bh(&txq->axq_lock);
2297 	}
2298 }
2299 
2300 /*****************/
2301 /* Init, Cleanup */
2302 /*****************/
2303 
2304 static int ath_txstatus_setup(struct ath_softc *sc, int size)
2305 {
2306 	struct ath_descdma *dd = &sc->txsdma;
2307 	u8 txs_len = sc->sc_ah->caps.txs_len;
2308 
2309 	dd->dd_desc_len = size * txs_len;
2310 	dd->dd_desc = dma_alloc_coherent(sc->dev, dd->dd_desc_len,
2311 					 &dd->dd_desc_paddr, GFP_KERNEL);
2312 	if (!dd->dd_desc)
2313 		return -ENOMEM;
2314 
2315 	return 0;
2316 }
2317 
2318 static int ath_tx_edma_init(struct ath_softc *sc)
2319 {
2320 	int err;
2321 
2322 	err = ath_txstatus_setup(sc, ATH_TXSTATUS_RING_SIZE);
2323 	if (!err)
2324 		ath9k_hw_setup_statusring(sc->sc_ah, sc->txsdma.dd_desc,
2325 					  sc->txsdma.dd_desc_paddr,
2326 					  ATH_TXSTATUS_RING_SIZE);
2327 
2328 	return err;
2329 }
2330 
2331 static void ath_tx_edma_cleanup(struct ath_softc *sc)
2332 {
2333 	struct ath_descdma *dd = &sc->txsdma;
2334 
2335 	dma_free_coherent(sc->dev, dd->dd_desc_len, dd->dd_desc,
2336 			  dd->dd_desc_paddr);
2337 }
2338 
2339 int ath_tx_init(struct ath_softc *sc, int nbufs)
2340 {
2341 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
2342 	int error = 0;
2343 
2344 	spin_lock_init(&sc->tx.txbuflock);
2345 
2346 	error = ath_descdma_setup(sc, &sc->tx.txdma, &sc->tx.txbuf,
2347 				  "tx", nbufs, 1, 1);
2348 	if (error != 0) {
2349 		ath_err(common,
2350 			"Failed to allocate tx descriptors: %d\n", error);
2351 		goto err;
2352 	}
2353 
2354 	error = ath_descdma_setup(sc, &sc->beacon.bdma, &sc->beacon.bbuf,
2355 				  "beacon", ATH_BCBUF, 1, 1);
2356 	if (error != 0) {
2357 		ath_err(common,
2358 			"Failed to allocate beacon descriptors: %d\n", error);
2359 		goto err;
2360 	}
2361 
2362 	INIT_DELAYED_WORK(&sc->tx_complete_work, ath_tx_complete_poll_work);
2363 
2364 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
2365 		error = ath_tx_edma_init(sc);
2366 		if (error)
2367 			goto err;
2368 	}
2369 
2370 err:
2371 	if (error != 0)
2372 		ath_tx_cleanup(sc);
2373 
2374 	return error;
2375 }
2376 
2377 void ath_tx_cleanup(struct ath_softc *sc)
2378 {
2379 	if (sc->beacon.bdma.dd_desc_len != 0)
2380 		ath_descdma_cleanup(sc, &sc->beacon.bdma, &sc->beacon.bbuf);
2381 
2382 	if (sc->tx.txdma.dd_desc_len != 0)
2383 		ath_descdma_cleanup(sc, &sc->tx.txdma, &sc->tx.txbuf);
2384 
2385 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
2386 		ath_tx_edma_cleanup(sc);
2387 }
2388 
2389 void ath_tx_node_init(struct ath_softc *sc, struct ath_node *an)
2390 {
2391 	struct ath_atx_tid *tid;
2392 	struct ath_atx_ac *ac;
2393 	int tidno, acno;
2394 
2395 	for (tidno = 0, tid = &an->tid[tidno];
2396 	     tidno < WME_NUM_TID;
2397 	     tidno++, tid++) {
2398 		tid->an        = an;
2399 		tid->tidno     = tidno;
2400 		tid->seq_start = tid->seq_next = 0;
2401 		tid->baw_size  = WME_MAX_BA;
2402 		tid->baw_head  = tid->baw_tail = 0;
2403 		tid->sched     = false;
2404 		tid->paused    = false;
2405 		tid->state &= ~AGGR_CLEANUP;
2406 		__skb_queue_head_init(&tid->buf_q);
2407 		acno = TID_TO_WME_AC(tidno);
2408 		tid->ac = &an->ac[acno];
2409 		tid->state &= ~AGGR_ADDBA_COMPLETE;
2410 		tid->state &= ~AGGR_ADDBA_PROGRESS;
2411 	}
2412 
2413 	for (acno = 0, ac = &an->ac[acno];
2414 	     acno < WME_NUM_AC; acno++, ac++) {
2415 		ac->sched    = false;
2416 		ac->txq = sc->tx.txq_map[acno];
2417 		INIT_LIST_HEAD(&ac->tid_q);
2418 	}
2419 }
2420 
2421 void ath_tx_node_cleanup(struct ath_softc *sc, struct ath_node *an)
2422 {
2423 	struct ath_atx_ac *ac;
2424 	struct ath_atx_tid *tid;
2425 	struct ath_txq *txq;
2426 	int tidno;
2427 
2428 	for (tidno = 0, tid = &an->tid[tidno];
2429 	     tidno < WME_NUM_TID; tidno++, tid++) {
2430 
2431 		ac = tid->ac;
2432 		txq = ac->txq;
2433 
2434 		spin_lock_bh(&txq->axq_lock);
2435 
2436 		if (tid->sched) {
2437 			list_del(&tid->list);
2438 			tid->sched = false;
2439 		}
2440 
2441 		if (ac->sched) {
2442 			list_del(&ac->list);
2443 			tid->ac->sched = false;
2444 		}
2445 
2446 		ath_tid_drain(sc, txq, tid);
2447 		tid->state &= ~AGGR_ADDBA_COMPLETE;
2448 		tid->state &= ~AGGR_CLEANUP;
2449 
2450 		spin_unlock_bh(&txq->axq_lock);
2451 	}
2452 }
2453