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1 /*
2  * Copyright (c) 2008 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 "core.h"
18 
19 #define BITS_PER_BYTE           8
20 #define OFDM_PLCP_BITS          22
21 #define HT_RC_2_MCS(_rc)        ((_rc) & 0x0f)
22 #define HT_RC_2_STREAMS(_rc)    ((((_rc) & 0x78) >> 3) + 1)
23 #define L_STF                   8
24 #define L_LTF                   8
25 #define L_SIG                   4
26 #define HT_SIG                  8
27 #define HT_STF                  4
28 #define HT_LTF(_ns)             (4 * (_ns))
29 #define SYMBOL_TIME(_ns)        ((_ns) << 2) /* ns * 4 us */
30 #define SYMBOL_TIME_HALFGI(_ns) (((_ns) * 18 + 4) / 5)  /* ns * 3.6 us */
31 #define NUM_SYMBOLS_PER_USEC(_usec) (_usec >> 2)
32 #define NUM_SYMBOLS_PER_USEC_HALFGI(_usec) (((_usec*5)-4)/18)
33 
34 #define OFDM_SIFS_TIME    	    16
35 
36 static u32 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 	{    52,  108 },     /*  8: BPSK */
47 	{   104,  216 },     /*  9: QPSK 1/2 */
48 	{   156,  324 },     /* 10: QPSK 3/4 */
49 	{   208,  432 },     /* 11: 16-QAM 1/2 */
50 	{   312,  648 },     /* 12: 16-QAM 3/4 */
51 	{   416,  864 },     /* 13: 64-QAM 2/3 */
52 	{   468,  972 },     /* 14: 64-QAM 3/4 */
53 	{   520, 1080 },     /* 15: 64-QAM 5/6 */
54 };
55 
56 #define IS_HT_RATE(_rate)     ((_rate) & 0x80)
57 
58 /*
59  * Insert a chain of ath_buf (descriptors) on a txq and
60  * assume the descriptors are already chained together by caller.
61  * NB: must be called with txq lock held
62  */
63 
ath_tx_txqaddbuf(struct ath_softc * sc,struct ath_txq * txq,struct list_head * head)64 static void ath_tx_txqaddbuf(struct ath_softc *sc, struct ath_txq *txq,
65 			     struct list_head *head)
66 {
67 	struct ath_hal *ah = sc->sc_ah;
68 	struct ath_buf *bf;
69 
70 	/*
71 	 * Insert the frame on the outbound list and
72 	 * pass it on to the hardware.
73 	 */
74 
75 	if (list_empty(head))
76 		return;
77 
78 	bf = list_first_entry(head, struct ath_buf, list);
79 
80 	list_splice_tail_init(head, &txq->axq_q);
81 	txq->axq_depth++;
82 	txq->axq_totalqueued++;
83 	txq->axq_linkbuf = list_entry(txq->axq_q.prev, struct ath_buf, list);
84 
85 	DPRINTF(sc, ATH_DBG_QUEUE,
86 		"qnum: %d, txq depth: %d\n", txq->axq_qnum, txq->axq_depth);
87 
88 	if (txq->axq_link == NULL) {
89 		ath9k_hw_puttxbuf(ah, txq->axq_qnum, bf->bf_daddr);
90 		DPRINTF(sc, ATH_DBG_XMIT,
91 			"TXDP[%u] = %llx (%p)\n",
92 			txq->axq_qnum, ito64(bf->bf_daddr), bf->bf_desc);
93 	} else {
94 		*txq->axq_link = bf->bf_daddr;
95 		DPRINTF(sc, ATH_DBG_XMIT, "link[%u] (%p)=%llx (%p)\n",
96 			txq->axq_qnum, txq->axq_link,
97 			ito64(bf->bf_daddr), bf->bf_desc);
98 	}
99 	txq->axq_link = &(bf->bf_lastbf->bf_desc->ds_link);
100 	ath9k_hw_txstart(ah, txq->axq_qnum);
101 }
102 
ath_tx_complete(struct ath_softc * sc,struct sk_buff * skb,struct ath_xmit_status * tx_status)103 static void ath_tx_complete(struct ath_softc *sc, struct sk_buff *skb,
104 			    struct ath_xmit_status *tx_status)
105 {
106 	struct ieee80211_hw *hw = sc->hw;
107 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
108 	struct ath_tx_info_priv *tx_info_priv = ATH_TX_INFO_PRIV(tx_info);
109 	int hdrlen, padsize;
110 
111 	DPRINTF(sc, ATH_DBG_XMIT, "TX complete: skb: %p\n", skb);
112 
113 	if (tx_info->flags & IEEE80211_TX_CTL_NO_ACK ||
114 	    tx_info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
115 		kfree(tx_info_priv);
116 		tx_info->rate_driver_data[0] = NULL;
117 	}
118 
119 	if (tx_status->flags & ATH_TX_BAR) {
120 		tx_info->flags |= IEEE80211_TX_STAT_AMPDU_NO_BACK;
121 		tx_status->flags &= ~ATH_TX_BAR;
122 	}
123 
124 	if (!(tx_status->flags & (ATH_TX_ERROR | ATH_TX_XRETRY))) {
125 		/* Frame was ACKed */
126 		tx_info->flags |= IEEE80211_TX_STAT_ACK;
127 	}
128 
129 	tx_info->status.rates[0].count = tx_status->retries + 1;
130 
131 	hdrlen = ieee80211_get_hdrlen_from_skb(skb);
132 	padsize = hdrlen & 3;
133 	if (padsize && hdrlen >= 24) {
134 		/*
135 		 * Remove MAC header padding before giving the frame back to
136 		 * mac80211.
137 		 */
138 		memmove(skb->data + padsize, skb->data, hdrlen);
139 		skb_pull(skb, padsize);
140 	}
141 
142 	ieee80211_tx_status(hw, skb);
143 }
144 
145 /* Check if it's okay to send out aggregates */
146 
ath_aggr_query(struct ath_softc * sc,struct ath_node * an,u8 tidno)147 static int ath_aggr_query(struct ath_softc *sc, struct ath_node *an, u8 tidno)
148 {
149 	struct ath_atx_tid *tid;
150 	tid = ATH_AN_2_TID(an, tidno);
151 
152 	if (tid->state & AGGR_ADDBA_COMPLETE ||
153 	    tid->state & AGGR_ADDBA_PROGRESS)
154 		return 1;
155 	else
156 		return 0;
157 }
158 
ath_get_beaconconfig(struct ath_softc * sc,int if_id,struct ath_beacon_config * conf)159 static void ath_get_beaconconfig(struct ath_softc *sc, int if_id,
160 				 struct ath_beacon_config *conf)
161 {
162 	struct ieee80211_hw *hw = sc->hw;
163 
164 	/* fill in beacon config data */
165 
166 	conf->beacon_interval = hw->conf.beacon_int;
167 	conf->listen_interval = 100;
168 	conf->dtim_count = 1;
169 	conf->bmiss_timeout = ATH_DEFAULT_BMISS_LIMIT * conf->listen_interval;
170 }
171 
172 /* Calculate Atheros packet type from IEEE80211 packet header */
173 
get_hw_packet_type(struct sk_buff * skb)174 static enum ath9k_pkt_type get_hw_packet_type(struct sk_buff *skb)
175 {
176 	struct ieee80211_hdr *hdr;
177 	enum ath9k_pkt_type htype;
178 	__le16 fc;
179 
180 	hdr = (struct ieee80211_hdr *)skb->data;
181 	fc = hdr->frame_control;
182 
183 	if (ieee80211_is_beacon(fc))
184 		htype = ATH9K_PKT_TYPE_BEACON;
185 	else if (ieee80211_is_probe_resp(fc))
186 		htype = ATH9K_PKT_TYPE_PROBE_RESP;
187 	else if (ieee80211_is_atim(fc))
188 		htype = ATH9K_PKT_TYPE_ATIM;
189 	else if (ieee80211_is_pspoll(fc))
190 		htype = ATH9K_PKT_TYPE_PSPOLL;
191 	else
192 		htype = ATH9K_PKT_TYPE_NORMAL;
193 
194 	return htype;
195 }
196 
is_pae(struct sk_buff * skb)197 static bool is_pae(struct sk_buff *skb)
198 {
199 	struct ieee80211_hdr *hdr;
200 	__le16 fc;
201 
202 	hdr = (struct ieee80211_hdr *)skb->data;
203 	fc = hdr->frame_control;
204 
205 	if (ieee80211_is_data(fc)) {
206 		if (ieee80211_is_nullfunc(fc) ||
207 		    /* Port Access Entity (IEEE 802.1X) */
208 		    (skb->protocol == cpu_to_be16(ETH_P_PAE))) {
209 			return true;
210 		}
211 	}
212 
213 	return false;
214 }
215 
get_hw_crypto_keytype(struct sk_buff * skb)216 static int get_hw_crypto_keytype(struct sk_buff *skb)
217 {
218 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
219 
220 	if (tx_info->control.hw_key) {
221 		if (tx_info->control.hw_key->alg == ALG_WEP)
222 			return ATH9K_KEY_TYPE_WEP;
223 		else if (tx_info->control.hw_key->alg == ALG_TKIP)
224 			return ATH9K_KEY_TYPE_TKIP;
225 		else if (tx_info->control.hw_key->alg == ALG_CCMP)
226 			return ATH9K_KEY_TYPE_AES;
227 	}
228 
229 	return ATH9K_KEY_TYPE_CLEAR;
230 }
231 
232 /* Called only when tx aggregation is enabled and HT is supported */
233 
assign_aggr_tid_seqno(struct sk_buff * skb,struct ath_buf * bf)234 static void assign_aggr_tid_seqno(struct sk_buff *skb,
235 				  struct ath_buf *bf)
236 {
237 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
238 	struct ieee80211_hdr *hdr;
239 	struct ath_node *an;
240 	struct ath_atx_tid *tid;
241 	__le16 fc;
242 	u8 *qc;
243 
244 	if (!tx_info->control.sta)
245 		return;
246 
247 	an = (struct ath_node *)tx_info->control.sta->drv_priv;
248 	hdr = (struct ieee80211_hdr *)skb->data;
249 	fc = hdr->frame_control;
250 
251 	/* Get tidno */
252 
253 	if (ieee80211_is_data_qos(fc)) {
254 		qc = ieee80211_get_qos_ctl(hdr);
255 		bf->bf_tidno = qc[0] & 0xf;
256 	}
257 
258 	/* Get seqno */
259 	/* For HT capable stations, we save tidno for later use.
260 	 * We also override seqno set by upper layer with the one
261 	 * in tx aggregation state.
262 	 *
263 	 * If fragmentation is on, the sequence number is
264 	 * not overridden, since it has been
265 	 * incremented by the fragmentation routine.
266 	 *
267 	 * FIXME: check if the fragmentation threshold exceeds
268 	 * IEEE80211 max.
269 	 */
270 	tid = ATH_AN_2_TID(an, bf->bf_tidno);
271 	hdr->seq_ctrl = cpu_to_le16(tid->seq_next <<
272 			IEEE80211_SEQ_SEQ_SHIFT);
273 	bf->bf_seqno = tid->seq_next;
274 	INCR(tid->seq_next, IEEE80211_SEQ_MAX);
275 }
276 
setup_tx_flags(struct ath_softc * sc,struct sk_buff * skb,struct ath_txq * txq)277 static int setup_tx_flags(struct ath_softc *sc, struct sk_buff *skb,
278 			  struct ath_txq *txq)
279 {
280 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
281 	int flags = 0;
282 
283 	flags |= ATH9K_TXDESC_CLRDMASK; /* needed for crypto errors */
284 	flags |= ATH9K_TXDESC_INTREQ;
285 
286 	if (tx_info->flags & IEEE80211_TX_CTL_NO_ACK)
287 		flags |= ATH9K_TXDESC_NOACK;
288 	if (tx_info->control.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
289 		flags |= ATH9K_TXDESC_RTSENA;
290 
291 	return flags;
292 }
293 
ath_tx_get_buffer(struct ath_softc * sc)294 static struct ath_buf *ath_tx_get_buffer(struct ath_softc *sc)
295 {
296 	struct ath_buf *bf = NULL;
297 
298 	spin_lock_bh(&sc->tx.txbuflock);
299 
300 	if (unlikely(list_empty(&sc->tx.txbuf))) {
301 		spin_unlock_bh(&sc->tx.txbuflock);
302 		return NULL;
303 	}
304 
305 	bf = list_first_entry(&sc->tx.txbuf, struct ath_buf, list);
306 	list_del(&bf->list);
307 
308 	spin_unlock_bh(&sc->tx.txbuflock);
309 
310 	return bf;
311 }
312 
313 /* To complete a chain of buffers associated a frame */
314 
ath_tx_complete_buf(struct ath_softc * sc,struct ath_buf * bf,struct list_head * bf_q,int txok,int sendbar)315 static void ath_tx_complete_buf(struct ath_softc *sc,
316 				struct ath_buf *bf,
317 				struct list_head *bf_q,
318 				int txok, int sendbar)
319 {
320 	struct sk_buff *skb = bf->bf_mpdu;
321 	struct ath_xmit_status tx_status;
322 	unsigned long flags;
323 
324 	/*
325 	 * Set retry information.
326 	 * NB: Don't use the information in the descriptor, because the frame
327 	 * could be software retried.
328 	 */
329 	tx_status.retries = bf->bf_retries;
330 	tx_status.flags = 0;
331 
332 	if (sendbar)
333 		tx_status.flags = ATH_TX_BAR;
334 
335 	if (!txok) {
336 		tx_status.flags |= ATH_TX_ERROR;
337 
338 		if (bf_isxretried(bf))
339 			tx_status.flags |= ATH_TX_XRETRY;
340 	}
341 
342 	/* Unmap this frame */
343 	pci_unmap_single(sc->pdev,
344 			 bf->bf_dmacontext,
345 			 skb->len,
346 			 PCI_DMA_TODEVICE);
347 	/* complete this frame */
348 	ath_tx_complete(sc, skb, &tx_status);
349 
350 	/*
351 	 * Return the list of ath_buf of this mpdu to free queue
352 	 */
353 	spin_lock_irqsave(&sc->tx.txbuflock, flags);
354 	list_splice_tail_init(bf_q, &sc->tx.txbuf);
355 	spin_unlock_irqrestore(&sc->tx.txbuflock, flags);
356 }
357 
358 /*
359  * queue up a dest/ac pair for tx scheduling
360  * NB: must be called with txq lock held
361  */
362 
ath_tx_queue_tid(struct ath_txq * txq,struct ath_atx_tid * tid)363 static void ath_tx_queue_tid(struct ath_txq *txq, struct ath_atx_tid *tid)
364 {
365 	struct ath_atx_ac *ac = tid->ac;
366 
367 	/*
368 	 * if tid is paused, hold off
369 	 */
370 	if (tid->paused)
371 		return;
372 
373 	/*
374 	 * add tid to ac atmost once
375 	 */
376 	if (tid->sched)
377 		return;
378 
379 	tid->sched = true;
380 	list_add_tail(&tid->list, &ac->tid_q);
381 
382 	/*
383 	 * add node ac to txq atmost once
384 	 */
385 	if (ac->sched)
386 		return;
387 
388 	ac->sched = true;
389 	list_add_tail(&ac->list, &txq->axq_acq);
390 }
391 
392 /* pause a tid */
393 
ath_tx_pause_tid(struct ath_softc * sc,struct ath_atx_tid * tid)394 static void ath_tx_pause_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
395 {
396 	struct ath_txq *txq = &sc->tx.txq[tid->ac->qnum];
397 
398 	spin_lock_bh(&txq->axq_lock);
399 
400 	tid->paused++;
401 
402 	spin_unlock_bh(&txq->axq_lock);
403 }
404 
405 /* resume a tid and schedule aggregate */
406 
ath_tx_resume_tid(struct ath_softc * sc,struct ath_atx_tid * tid)407 void ath_tx_resume_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
408 {
409 	struct ath_txq *txq = &sc->tx.txq[tid->ac->qnum];
410 
411 	ASSERT(tid->paused > 0);
412 	spin_lock_bh(&txq->axq_lock);
413 
414 	tid->paused--;
415 
416 	if (tid->paused > 0)
417 		goto unlock;
418 
419 	if (list_empty(&tid->buf_q))
420 		goto unlock;
421 
422 	/*
423 	 * Add this TID to scheduler and try to send out aggregates
424 	 */
425 	ath_tx_queue_tid(txq, tid);
426 	ath_txq_schedule(sc, txq);
427 unlock:
428 	spin_unlock_bh(&txq->axq_lock);
429 }
430 
431 /* Compute the number of bad frames */
432 
ath_tx_num_badfrms(struct ath_softc * sc,struct ath_buf * bf,int txok)433 static int ath_tx_num_badfrms(struct ath_softc *sc, struct ath_buf *bf,
434 			      int txok)
435 {
436 	struct ath_buf *bf_last = bf->bf_lastbf;
437 	struct ath_desc *ds = bf_last->bf_desc;
438 	u16 seq_st = 0;
439 	u32 ba[WME_BA_BMP_SIZE >> 5];
440 	int ba_index;
441 	int nbad = 0;
442 	int isaggr = 0;
443 
444 	if (ds->ds_txstat.ts_flags == ATH9K_TX_SW_ABORTED)
445 		return 0;
446 
447 	isaggr = bf_isaggr(bf);
448 	if (isaggr) {
449 		seq_st = ATH_DS_BA_SEQ(ds);
450 		memcpy(ba, ATH_DS_BA_BITMAP(ds), WME_BA_BMP_SIZE >> 3);
451 	}
452 
453 	while (bf) {
454 		ba_index = ATH_BA_INDEX(seq_st, bf->bf_seqno);
455 		if (!txok || (isaggr && !ATH_BA_ISSET(ba, ba_index)))
456 			nbad++;
457 
458 		bf = bf->bf_next;
459 	}
460 
461 	return nbad;
462 }
463 
ath_tx_set_retry(struct ath_softc * sc,struct ath_buf * bf)464 static void ath_tx_set_retry(struct ath_softc *sc, struct ath_buf *bf)
465 {
466 	struct sk_buff *skb;
467 	struct ieee80211_hdr *hdr;
468 
469 	bf->bf_state.bf_type |= BUF_RETRY;
470 	bf->bf_retries++;
471 
472 	skb = bf->bf_mpdu;
473 	hdr = (struct ieee80211_hdr *)skb->data;
474 	hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_RETRY);
475 }
476 
477 /* Update block ack window */
478 
ath_tx_update_baw(struct ath_softc * sc,struct ath_atx_tid * tid,int seqno)479 static void ath_tx_update_baw(struct ath_softc *sc, struct ath_atx_tid *tid,
480 			      int seqno)
481 {
482 	int index, cindex;
483 
484 	index  = ATH_BA_INDEX(tid->seq_start, seqno);
485 	cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
486 
487 	tid->tx_buf[cindex] = NULL;
488 
489 	while (tid->baw_head != tid->baw_tail && !tid->tx_buf[tid->baw_head]) {
490 		INCR(tid->seq_start, IEEE80211_SEQ_MAX);
491 		INCR(tid->baw_head, ATH_TID_MAX_BUFS);
492 	}
493 }
494 
495 /*
496  * ath_pkt_dur - compute packet duration (NB: not NAV)
497  *
498  * rix - rate index
499  * pktlen - total bytes (delims + data + fcs + pads + pad delims)
500  * width  - 0 for 20 MHz, 1 for 40 MHz
501  * half_gi - to use 4us v/s 3.6 us for symbol time
502  */
ath_pkt_duration(struct ath_softc * sc,u8 rix,struct ath_buf * bf,int width,int half_gi,bool shortPreamble)503 static u32 ath_pkt_duration(struct ath_softc *sc, u8 rix, struct ath_buf *bf,
504 			    int width, int half_gi, bool shortPreamble)
505 {
506 	struct ath_rate_table *rate_table = sc->cur_rate_table;
507 	u32 nbits, nsymbits, duration, nsymbols;
508 	u8 rc;
509 	int streams, pktlen;
510 
511 	pktlen = bf_isaggr(bf) ? bf->bf_al : bf->bf_frmlen;
512 	rc = rate_table->info[rix].ratecode;
513 
514 	/* for legacy rates, use old function to compute packet duration */
515 	if (!IS_HT_RATE(rc))
516 		return ath9k_hw_computetxtime(sc->sc_ah, rate_table, pktlen,
517 					      rix, shortPreamble);
518 
519 	/* find number of symbols: PLCP + data */
520 	nbits = (pktlen << 3) + OFDM_PLCP_BITS;
521 	nsymbits = bits_per_symbol[HT_RC_2_MCS(rc)][width];
522 	nsymbols = (nbits + nsymbits - 1) / nsymbits;
523 
524 	if (!half_gi)
525 		duration = SYMBOL_TIME(nsymbols);
526 	else
527 		duration = SYMBOL_TIME_HALFGI(nsymbols);
528 
529 	/* addup duration for legacy/ht training and signal fields */
530 	streams = HT_RC_2_STREAMS(rc);
531 	duration += L_STF + L_LTF + L_SIG + HT_SIG + HT_STF + HT_LTF(streams);
532 
533 	return duration;
534 }
535 
536 /* Rate module function to set rate related fields in tx descriptor */
537 
ath_buf_set_rate(struct ath_softc * sc,struct ath_buf * bf)538 static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf)
539 {
540 	struct ath_hal *ah = sc->sc_ah;
541 	struct ath_rate_table *rt;
542 	struct ath_desc *ds = bf->bf_desc;
543 	struct ath_desc *lastds = bf->bf_lastbf->bf_desc;
544 	struct ath9k_11n_rate_series series[4];
545 	struct sk_buff *skb;
546 	struct ieee80211_tx_info *tx_info;
547 	struct ieee80211_tx_rate *rates;
548 	struct ieee80211_hdr *hdr;
549 	int i, flags, rtsctsena = 0;
550 	u32 ctsduration = 0;
551 	u8 rix = 0, cix, ctsrate = 0;
552 	__le16 fc;
553 
554 	memset(series, 0, sizeof(struct ath9k_11n_rate_series) * 4);
555 
556 	skb = (struct sk_buff *)bf->bf_mpdu;
557 	hdr = (struct ieee80211_hdr *)skb->data;
558 	fc = hdr->frame_control;
559 	tx_info = IEEE80211_SKB_CB(skb);
560 	rates = tx_info->control.rates;
561 
562 	if (ieee80211_has_morefrags(fc) ||
563 	    (le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG)) {
564 		rates[1].count = rates[2].count = rates[3].count = 0;
565 		rates[1].idx = rates[2].idx = rates[3].idx = 0;
566 		rates[0].count = ATH_TXMAXTRY;
567 	}
568 
569 	/* get the cix for the lowest valid rix */
570 	rt = sc->cur_rate_table;
571 	for (i = 3; i >= 0; i--) {
572 		if (rates[i].count && (rates[i].idx >= 0)) {
573 			rix = rates[i].idx;
574 			break;
575 		}
576 	}
577 
578 	flags = (bf->bf_flags & (ATH9K_TXDESC_RTSENA | ATH9K_TXDESC_CTSENA));
579 	cix = rt->info[rix].ctrl_rate;
580 
581 	/*
582 	 * If 802.11g protection is enabled, determine whether to use RTS/CTS or
583 	 * just CTS.  Note that this is only done for OFDM/HT unicast frames.
584 	 */
585 	if (sc->sc_protmode != PROT_M_NONE && !(bf->bf_flags & ATH9K_TXDESC_NOACK)
586 	    && (rt->info[rix].phy == WLAN_RC_PHY_OFDM ||
587 		WLAN_RC_PHY_HT(rt->info[rix].phy))) {
588 		if (sc->sc_protmode == PROT_M_RTSCTS)
589 			flags = ATH9K_TXDESC_RTSENA;
590 		else if (sc->sc_protmode == PROT_M_CTSONLY)
591 			flags = ATH9K_TXDESC_CTSENA;
592 
593 		cix = rt->info[sc->sc_protrix].ctrl_rate;
594 		rtsctsena = 1;
595 	}
596 
597 	/* For 11n, the default behavior is to enable RTS for hw retried frames.
598 	 * We enable the global flag here and let rate series flags determine
599 	 * which rates will actually use RTS.
600 	 */
601 	if ((ah->ah_caps.hw_caps & ATH9K_HW_CAP_HT) && bf_isdata(bf)) {
602 		/* 802.11g protection not needed, use our default behavior */
603 		if (!rtsctsena)
604 			flags = ATH9K_TXDESC_RTSENA;
605 	}
606 
607 	/* Set protection if aggregate protection on */
608 	if (sc->sc_config.ath_aggr_prot &&
609 	    (!bf_isaggr(bf) || (bf_isaggr(bf) && bf->bf_al < 8192))) {
610 		flags = ATH9K_TXDESC_RTSENA;
611 		cix = rt->info[sc->sc_protrix].ctrl_rate;
612 		rtsctsena = 1;
613 	}
614 
615 	/* For AR5416 - RTS cannot be followed by a frame larger than 8K */
616 	if (bf_isaggr(bf) && (bf->bf_al > ah->ah_caps.rts_aggr_limit))
617 		flags &= ~(ATH9K_TXDESC_RTSENA);
618 
619 	/*
620 	 * CTS transmit rate is derived from the transmit rate by looking in the
621 	 * h/w rate table.  We must also factor in whether or not a short
622 	 * preamble is to be used. NB: cix is set above where RTS/CTS is enabled
623 	 */
624 	ctsrate = rt->info[cix].ratecode |
625 		(bf_isshpreamble(bf) ? rt->info[cix].short_preamble : 0);
626 
627 	for (i = 0; i < 4; i++) {
628 		if (!rates[i].count || (rates[i].idx < 0))
629 			continue;
630 
631 		rix = rates[i].idx;
632 
633 		series[i].Rate = rt->info[rix].ratecode |
634 			(bf_isshpreamble(bf) ? rt->info[rix].short_preamble : 0);
635 
636 		series[i].Tries = rates[i].count;
637 
638 		series[i].RateFlags = (
639 			(rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS) ?
640 				ATH9K_RATESERIES_RTS_CTS : 0) |
641 			((rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH) ?
642 				ATH9K_RATESERIES_2040 : 0) |
643 			((rates[i].flags & IEEE80211_TX_RC_SHORT_GI) ?
644 				ATH9K_RATESERIES_HALFGI : 0);
645 
646 		series[i].PktDuration = ath_pkt_duration(sc, rix, bf,
647 			 (rates[i].flags & IEEE80211_TX_RC_40_MHZ_WIDTH) != 0,
648 			 (rates[i].flags & IEEE80211_TX_RC_SHORT_GI),
649 			 bf_isshpreamble(bf));
650 
651 		series[i].ChSel = sc->sc_tx_chainmask;
652 
653 		if (rtsctsena)
654 			series[i].RateFlags |= ATH9K_RATESERIES_RTS_CTS;
655 	}
656 
657 	/* set dur_update_en for l-sig computation except for PS-Poll frames */
658 	ath9k_hw_set11n_ratescenario(ah, ds, lastds, !bf_ispspoll(bf),
659 				     ctsrate, ctsduration,
660 				     series, 4, flags);
661 
662 	if (sc->sc_config.ath_aggr_prot && flags)
663 		ath9k_hw_set11n_burstduration(ah, ds, 8192);
664 }
665 
666 /*
667  * Function to send a normal HT (non-AMPDU) frame
668  * NB: must be called with txq lock held
669  */
ath_tx_send_normal(struct ath_softc * sc,struct ath_txq * txq,struct ath_atx_tid * tid,struct list_head * bf_head)670 static int ath_tx_send_normal(struct ath_softc *sc,
671 			      struct ath_txq *txq,
672 			      struct ath_atx_tid *tid,
673 			      struct list_head *bf_head)
674 {
675 	struct ath_buf *bf;
676 
677 	BUG_ON(list_empty(bf_head));
678 
679 	bf = list_first_entry(bf_head, struct ath_buf, list);
680 	bf->bf_state.bf_type &= ~BUF_AMPDU; /* regular HT frame */
681 
682 	/* update starting sequence number for subsequent ADDBA request */
683 	INCR(tid->seq_start, IEEE80211_SEQ_MAX);
684 
685 	/* Queue to h/w without aggregation */
686 	bf->bf_nframes = 1;
687 	bf->bf_lastbf = bf->bf_lastfrm; /* one single frame */
688 	ath_buf_set_rate(sc, bf);
689 	ath_tx_txqaddbuf(sc, txq, bf_head);
690 
691 	return 0;
692 }
693 
694 /* flush tid's software queue and send frames as non-ampdu's */
695 
ath_tx_flush_tid(struct ath_softc * sc,struct ath_atx_tid * tid)696 static void ath_tx_flush_tid(struct ath_softc *sc, struct ath_atx_tid *tid)
697 {
698 	struct ath_txq *txq = &sc->tx.txq[tid->ac->qnum];
699 	struct ath_buf *bf;
700 	struct list_head bf_head;
701 	INIT_LIST_HEAD(&bf_head);
702 
703 	ASSERT(tid->paused > 0);
704 	spin_lock_bh(&txq->axq_lock);
705 
706 	tid->paused--;
707 
708 	if (tid->paused > 0) {
709 		spin_unlock_bh(&txq->axq_lock);
710 		return;
711 	}
712 
713 	while (!list_empty(&tid->buf_q)) {
714 		bf = list_first_entry(&tid->buf_q, struct ath_buf, list);
715 		ASSERT(!bf_isretried(bf));
716 		list_cut_position(&bf_head, &tid->buf_q, &bf->bf_lastfrm->list);
717 		ath_tx_send_normal(sc, txq, tid, &bf_head);
718 	}
719 
720 	spin_unlock_bh(&txq->axq_lock);
721 }
722 
723 /* Completion routine of an aggregate */
724 
ath_tx_complete_aggr_rifs(struct ath_softc * sc,struct ath_txq * txq,struct ath_buf * bf,struct list_head * bf_q,int txok)725 static void ath_tx_complete_aggr_rifs(struct ath_softc *sc,
726 				      struct ath_txq *txq,
727 				      struct ath_buf *bf,
728 				      struct list_head *bf_q,
729 				      int txok)
730 {
731 	struct ath_node *an = NULL;
732 	struct sk_buff *skb;
733 	struct ieee80211_tx_info *tx_info;
734 	struct ath_atx_tid *tid = NULL;
735 	struct ath_buf *bf_last = bf->bf_lastbf;
736 	struct ath_desc *ds = bf_last->bf_desc;
737 	struct ath_buf *bf_next, *bf_lastq = NULL;
738 	struct list_head bf_head, bf_pending;
739 	u16 seq_st = 0;
740 	u32 ba[WME_BA_BMP_SIZE >> 5];
741 	int isaggr, txfail, txpending, sendbar = 0, needreset = 0;
742 
743 	skb = (struct sk_buff *)bf->bf_mpdu;
744 	tx_info = IEEE80211_SKB_CB(skb);
745 
746 	if (tx_info->control.sta) {
747 		an = (struct ath_node *)tx_info->control.sta->drv_priv;
748 		tid = ATH_AN_2_TID(an, bf->bf_tidno);
749 	}
750 
751 	isaggr = bf_isaggr(bf);
752 	if (isaggr) {
753 		if (txok) {
754 			if (ATH_DS_TX_BA(ds)) {
755 				/*
756 				 * extract starting sequence and
757 				 * block-ack bitmap
758 				 */
759 				seq_st = ATH_DS_BA_SEQ(ds);
760 				memcpy(ba,
761 					ATH_DS_BA_BITMAP(ds),
762 					WME_BA_BMP_SIZE >> 3);
763 			} else {
764 				memset(ba, 0, WME_BA_BMP_SIZE >> 3);
765 
766 				/*
767 				 * AR5416 can become deaf/mute when BA
768 				 * issue happens. Chip needs to be reset.
769 				 * But AP code may have sychronization issues
770 				 * when perform internal reset in this routine.
771 				 * Only enable reset in STA mode for now.
772 				 */
773 				if (sc->sc_ah->ah_opmode ==
774 					    NL80211_IFTYPE_STATION)
775 					needreset = 1;
776 			}
777 		} else {
778 			memset(ba, 0, WME_BA_BMP_SIZE >> 3);
779 		}
780 	}
781 
782 	INIT_LIST_HEAD(&bf_pending);
783 	INIT_LIST_HEAD(&bf_head);
784 
785 	while (bf) {
786 		txfail = txpending = 0;
787 		bf_next = bf->bf_next;
788 
789 		if (ATH_BA_ISSET(ba, ATH_BA_INDEX(seq_st, bf->bf_seqno))) {
790 			/* transmit completion, subframe is
791 			 * acked by block ack */
792 		} else if (!isaggr && txok) {
793 			/* transmit completion */
794 		} else {
795 
796 			if (!(tid->state & AGGR_CLEANUP) &&
797 			    ds->ds_txstat.ts_flags != ATH9K_TX_SW_ABORTED) {
798 				if (bf->bf_retries < ATH_MAX_SW_RETRIES) {
799 					ath_tx_set_retry(sc, bf);
800 					txpending = 1;
801 				} else {
802 					bf->bf_state.bf_type |= BUF_XRETRY;
803 					txfail = 1;
804 					sendbar = 1;
805 				}
806 			} else {
807 				/*
808 				 * cleanup in progress, just fail
809 				 * the un-acked sub-frames
810 				 */
811 				txfail = 1;
812 			}
813 		}
814 		/*
815 		 * Remove ath_buf's of this sub-frame from aggregate queue.
816 		 */
817 		if (bf_next == NULL) {  /* last subframe in the aggregate */
818 			ASSERT(bf->bf_lastfrm == bf_last);
819 
820 			/*
821 			 * The last descriptor of the last sub frame could be
822 			 * a holding descriptor for h/w. If that's the case,
823 			 * bf->bf_lastfrm won't be in the bf_q.
824 			 * Make sure we handle bf_q properly here.
825 			 */
826 
827 			if (!list_empty(bf_q)) {
828 				bf_lastq = list_entry(bf_q->prev,
829 					struct ath_buf, list);
830 				list_cut_position(&bf_head,
831 					bf_q, &bf_lastq->list);
832 			} else {
833 				/*
834 				 * XXX: if the last subframe only has one
835 				 * descriptor which is also being used as
836 				 * a holding descriptor. Then the ath_buf
837 				 * is not in the bf_q at all.
838 				 */
839 				INIT_LIST_HEAD(&bf_head);
840 			}
841 		} else {
842 			ASSERT(!list_empty(bf_q));
843 			list_cut_position(&bf_head,
844 				bf_q, &bf->bf_lastfrm->list);
845 		}
846 
847 		if (!txpending) {
848 			/*
849 			 * complete the acked-ones/xretried ones; update
850 			 * block-ack window
851 			 */
852 			spin_lock_bh(&txq->axq_lock);
853 			ath_tx_update_baw(sc, tid, bf->bf_seqno);
854 			spin_unlock_bh(&txq->axq_lock);
855 
856 			/* complete this sub-frame */
857 			ath_tx_complete_buf(sc, bf, &bf_head, !txfail, sendbar);
858 		} else {
859 			/*
860 			 * retry the un-acked ones
861 			 */
862 			/*
863 			 * XXX: if the last descriptor is holding descriptor,
864 			 * in order to requeue the frame to software queue, we
865 			 * need to allocate a new descriptor and
866 			 * copy the content of holding descriptor to it.
867 			 */
868 			if (bf->bf_next == NULL &&
869 			    bf_last->bf_status & ATH_BUFSTATUS_STALE) {
870 				struct ath_buf *tbf;
871 
872 				/* allocate new descriptor */
873 				spin_lock_bh(&sc->tx.txbuflock);
874 				ASSERT(!list_empty((&sc->tx.txbuf)));
875 				tbf = list_first_entry(&sc->tx.txbuf,
876 						struct ath_buf, list);
877 				list_del(&tbf->list);
878 				spin_unlock_bh(&sc->tx.txbuflock);
879 
880 				ATH_TXBUF_RESET(tbf);
881 
882 				/* copy descriptor content */
883 				tbf->bf_mpdu = bf_last->bf_mpdu;
884 				tbf->bf_buf_addr = bf_last->bf_buf_addr;
885 				*(tbf->bf_desc) = *(bf_last->bf_desc);
886 
887 				/* link it to the frame */
888 				if (bf_lastq) {
889 					bf_lastq->bf_desc->ds_link =
890 						tbf->bf_daddr;
891 					bf->bf_lastfrm = tbf;
892 					ath9k_hw_cleartxdesc(sc->sc_ah,
893 						bf->bf_lastfrm->bf_desc);
894 				} else {
895 					tbf->bf_state = bf_last->bf_state;
896 					tbf->bf_lastfrm = tbf;
897 					ath9k_hw_cleartxdesc(sc->sc_ah,
898 						tbf->bf_lastfrm->bf_desc);
899 
900 					/* copy the DMA context */
901 					tbf->bf_dmacontext =
902 						bf_last->bf_dmacontext;
903 				}
904 				list_add_tail(&tbf->list, &bf_head);
905 			} else {
906 				/*
907 				 * Clear descriptor status words for
908 				 * software retry
909 				 */
910 				ath9k_hw_cleartxdesc(sc->sc_ah,
911 						     bf->bf_lastfrm->bf_desc);
912 			}
913 
914 			/*
915 			 * Put this buffer to the temporary pending
916 			 * queue to retain ordering
917 			 */
918 			list_splice_tail_init(&bf_head, &bf_pending);
919 		}
920 
921 		bf = bf_next;
922 	}
923 
924 	if (tid->state & AGGR_CLEANUP) {
925 		/* check to see if we're done with cleaning the h/w queue */
926 		spin_lock_bh(&txq->axq_lock);
927 
928 		if (tid->baw_head == tid->baw_tail) {
929 			tid->state &= ~AGGR_ADDBA_COMPLETE;
930 			tid->addba_exchangeattempts = 0;
931 			spin_unlock_bh(&txq->axq_lock);
932 
933 			tid->state &= ~AGGR_CLEANUP;
934 
935 			/* send buffered frames as singles */
936 			ath_tx_flush_tid(sc, tid);
937 		} else
938 			spin_unlock_bh(&txq->axq_lock);
939 
940 		return;
941 	}
942 
943 	/*
944 	 * prepend un-acked frames to the beginning of the pending frame queue
945 	 */
946 	if (!list_empty(&bf_pending)) {
947 		spin_lock_bh(&txq->axq_lock);
948 		/* Note: we _prepend_, we _do_not_ at to
949 		 * the end of the queue ! */
950 		list_splice(&bf_pending, &tid->buf_q);
951 		ath_tx_queue_tid(txq, tid);
952 		spin_unlock_bh(&txq->axq_lock);
953 	}
954 
955 	if (needreset)
956 		ath_reset(sc, false);
957 
958 	return;
959 }
960 
ath_tx_rc_status(struct ath_buf * bf,struct ath_desc * ds,int nbad)961 static void ath_tx_rc_status(struct ath_buf *bf, struct ath_desc *ds, int nbad)
962 {
963 	struct sk_buff *skb = (struct sk_buff *)bf->bf_mpdu;
964 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
965 	struct ath_tx_info_priv *tx_info_priv = ATH_TX_INFO_PRIV(tx_info);
966 
967 	tx_info_priv->update_rc = false;
968 	if (ds->ds_txstat.ts_status & ATH9K_TXERR_FILT)
969 		tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
970 
971 	if ((ds->ds_txstat.ts_status & ATH9K_TXERR_FILT) == 0 &&
972 	    (bf->bf_flags & ATH9K_TXDESC_NOACK) == 0) {
973 		if (bf_isdata(bf)) {
974 			memcpy(&tx_info_priv->tx, &ds->ds_txstat,
975 			       sizeof(tx_info_priv->tx));
976 			tx_info_priv->n_frames = bf->bf_nframes;
977 			tx_info_priv->n_bad_frames = nbad;
978 			tx_info_priv->update_rc = true;
979 		}
980 	}
981 }
982 
983 /* Process completed xmit descriptors from the specified queue */
984 
ath_tx_processq(struct ath_softc * sc,struct ath_txq * txq)985 static void ath_tx_processq(struct ath_softc *sc, struct ath_txq *txq)
986 {
987 	struct ath_hal *ah = sc->sc_ah;
988 	struct ath_buf *bf, *lastbf, *bf_held = NULL;
989 	struct list_head bf_head;
990 	struct ath_desc *ds;
991 	int txok, nbad = 0;
992 	int status;
993 
994 	DPRINTF(sc, ATH_DBG_QUEUE, "tx queue %d (%x), link %p\n",
995 		txq->axq_qnum, ath9k_hw_gettxbuf(sc->sc_ah, txq->axq_qnum),
996 		txq->axq_link);
997 
998 	for (;;) {
999 		spin_lock_bh(&txq->axq_lock);
1000 		if (list_empty(&txq->axq_q)) {
1001 			txq->axq_link = NULL;
1002 			txq->axq_linkbuf = NULL;
1003 			spin_unlock_bh(&txq->axq_lock);
1004 			break;
1005 		}
1006 		bf = list_first_entry(&txq->axq_q, struct ath_buf, list);
1007 
1008 		/*
1009 		 * There is a race condition that a BH gets scheduled
1010 		 * after sw writes TxE and before hw re-load the last
1011 		 * descriptor to get the newly chained one.
1012 		 * Software must keep the last DONE descriptor as a
1013 		 * holding descriptor - software does so by marking
1014 		 * it with the STALE flag.
1015 		 */
1016 		bf_held = NULL;
1017 		if (bf->bf_status & ATH_BUFSTATUS_STALE) {
1018 			bf_held = bf;
1019 			if (list_is_last(&bf_held->list, &txq->axq_q)) {
1020 				/* FIXME:
1021 				 * The holding descriptor is the last
1022 				 * descriptor in queue. It's safe to remove
1023 				 * the last holding descriptor in BH context.
1024 				 */
1025 				spin_unlock_bh(&txq->axq_lock);
1026 				break;
1027 			} else {
1028 				/* Lets work with the next buffer now */
1029 				bf = list_entry(bf_held->list.next,
1030 					struct ath_buf, list);
1031 			}
1032 		}
1033 
1034 		lastbf = bf->bf_lastbf;
1035 		ds = lastbf->bf_desc;    /* NB: last decriptor */
1036 
1037 		status = ath9k_hw_txprocdesc(ah, ds);
1038 		if (status == -EINPROGRESS) {
1039 			spin_unlock_bh(&txq->axq_lock);
1040 			break;
1041 		}
1042 		if (bf->bf_desc == txq->axq_lastdsWithCTS)
1043 			txq->axq_lastdsWithCTS = NULL;
1044 		if (ds == txq->axq_gatingds)
1045 			txq->axq_gatingds = NULL;
1046 
1047 		/*
1048 		 * Remove ath_buf's of the same transmit unit from txq,
1049 		 * however leave the last descriptor back as the holding
1050 		 * descriptor for hw.
1051 		 */
1052 		lastbf->bf_status |= ATH_BUFSTATUS_STALE;
1053 		INIT_LIST_HEAD(&bf_head);
1054 
1055 		if (!list_is_singular(&lastbf->list))
1056 			list_cut_position(&bf_head,
1057 				&txq->axq_q, lastbf->list.prev);
1058 
1059 		txq->axq_depth--;
1060 
1061 		if (bf_isaggr(bf))
1062 			txq->axq_aggr_depth--;
1063 
1064 		txok = (ds->ds_txstat.ts_status == 0);
1065 
1066 		spin_unlock_bh(&txq->axq_lock);
1067 
1068 		if (bf_held) {
1069 			list_del(&bf_held->list);
1070 			spin_lock_bh(&sc->tx.txbuflock);
1071 			list_add_tail(&bf_held->list, &sc->tx.txbuf);
1072 			spin_unlock_bh(&sc->tx.txbuflock);
1073 		}
1074 
1075 		if (!bf_isampdu(bf)) {
1076 			/*
1077 			 * This frame is sent out as a single frame.
1078 			 * Use hardware retry status for this frame.
1079 			 */
1080 			bf->bf_retries = ds->ds_txstat.ts_longretry;
1081 			if (ds->ds_txstat.ts_status & ATH9K_TXERR_XRETRY)
1082 				bf->bf_state.bf_type |= BUF_XRETRY;
1083 			nbad = 0;
1084 		} else {
1085 			nbad = ath_tx_num_badfrms(sc, bf, txok);
1086 		}
1087 
1088 		ath_tx_rc_status(bf, ds, nbad);
1089 
1090 		/*
1091 		 * Complete this transmit unit
1092 		 */
1093 		if (bf_isampdu(bf))
1094 			ath_tx_complete_aggr_rifs(sc, txq, bf, &bf_head, txok);
1095 		else
1096 			ath_tx_complete_buf(sc, bf, &bf_head, txok, 0);
1097 
1098 		/* Wake up mac80211 queue */
1099 
1100 		spin_lock_bh(&txq->axq_lock);
1101 		if (txq->stopped && ath_txq_depth(sc, txq->axq_qnum) <=
1102 				(ATH_TXBUF - 20)) {
1103 			int qnum;
1104 			qnum = ath_get_mac80211_qnum(txq->axq_qnum, sc);
1105 			if (qnum != -1) {
1106 				ieee80211_wake_queue(sc->hw, qnum);
1107 				txq->stopped = 0;
1108 			}
1109 
1110 		}
1111 
1112 		/*
1113 		 * schedule any pending packets if aggregation is enabled
1114 		 */
1115 		if (sc->sc_flags & SC_OP_TXAGGR)
1116 			ath_txq_schedule(sc, txq);
1117 		spin_unlock_bh(&txq->axq_lock);
1118 	}
1119 }
1120 
ath_tx_stopdma(struct ath_softc * sc,struct ath_txq * txq)1121 static void ath_tx_stopdma(struct ath_softc *sc, struct ath_txq *txq)
1122 {
1123 	struct ath_hal *ah = sc->sc_ah;
1124 
1125 	(void) ath9k_hw_stoptxdma(ah, txq->axq_qnum);
1126 	DPRINTF(sc, ATH_DBG_XMIT, "tx queue [%u] %x, link %p\n",
1127 		txq->axq_qnum, ath9k_hw_gettxbuf(ah, txq->axq_qnum),
1128 		txq->axq_link);
1129 }
1130 
1131 /* Drain only the data queues */
1132 
ath_drain_txdataq(struct ath_softc * sc,bool retry_tx)1133 static void ath_drain_txdataq(struct ath_softc *sc, bool retry_tx)
1134 {
1135 	struct ath_hal *ah = sc->sc_ah;
1136 	int i, status, npend = 0;
1137 
1138 	if (!(sc->sc_flags & SC_OP_INVALID)) {
1139 		for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
1140 			if (ATH_TXQ_SETUP(sc, i)) {
1141 				ath_tx_stopdma(sc, &sc->tx.txq[i]);
1142 				/* The TxDMA may not really be stopped.
1143 				 * Double check the hal tx pending count */
1144 				npend += ath9k_hw_numtxpending(ah,
1145 						       sc->tx.txq[i].axq_qnum);
1146 			}
1147 		}
1148 	}
1149 
1150 	if (npend) {
1151 		/* TxDMA not stopped, reset the hal */
1152 		DPRINTF(sc, ATH_DBG_XMIT, "Unable to stop TxDMA. Reset HAL!\n");
1153 
1154 		spin_lock_bh(&sc->sc_resetlock);
1155 		if (!ath9k_hw_reset(ah,
1156 				    sc->sc_ah->ah_curchan,
1157 				    sc->tx_chan_width,
1158 				    sc->sc_tx_chainmask, sc->sc_rx_chainmask,
1159 				    sc->sc_ht_extprotspacing, true, &status)) {
1160 
1161 			DPRINTF(sc, ATH_DBG_FATAL,
1162 				"Unable to reset hardware; hal status %u\n",
1163 				status);
1164 		}
1165 		spin_unlock_bh(&sc->sc_resetlock);
1166 	}
1167 
1168 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
1169 		if (ATH_TXQ_SETUP(sc, i))
1170 			ath_tx_draintxq(sc, &sc->tx.txq[i], retry_tx);
1171 	}
1172 }
1173 
1174 /* Add a sub-frame to block ack window */
1175 
ath_tx_addto_baw(struct ath_softc * sc,struct ath_atx_tid * tid,struct ath_buf * bf)1176 static void ath_tx_addto_baw(struct ath_softc *sc,
1177 			     struct ath_atx_tid *tid,
1178 			     struct ath_buf *bf)
1179 {
1180 	int index, cindex;
1181 
1182 	if (bf_isretried(bf))
1183 		return;
1184 
1185 	index  = ATH_BA_INDEX(tid->seq_start, bf->bf_seqno);
1186 	cindex = (tid->baw_head + index) & (ATH_TID_MAX_BUFS - 1);
1187 
1188 	ASSERT(tid->tx_buf[cindex] == NULL);
1189 	tid->tx_buf[cindex] = bf;
1190 
1191 	if (index >= ((tid->baw_tail - tid->baw_head) &
1192 		(ATH_TID_MAX_BUFS - 1))) {
1193 		tid->baw_tail = cindex;
1194 		INCR(tid->baw_tail, ATH_TID_MAX_BUFS);
1195 	}
1196 }
1197 
1198 /*
1199  * Function to send an A-MPDU
1200  * NB: must be called with txq lock held
1201  */
ath_tx_send_ampdu(struct ath_softc * sc,struct ath_atx_tid * tid,struct list_head * bf_head,struct ath_tx_control * txctl)1202 static int ath_tx_send_ampdu(struct ath_softc *sc,
1203 			     struct ath_atx_tid *tid,
1204 			     struct list_head *bf_head,
1205 			     struct ath_tx_control *txctl)
1206 {
1207 	struct ath_buf *bf;
1208 
1209 	BUG_ON(list_empty(bf_head));
1210 
1211 	bf = list_first_entry(bf_head, struct ath_buf, list);
1212 	bf->bf_state.bf_type |= BUF_AMPDU;
1213 
1214 	/*
1215 	 * Do not queue to h/w when any of the following conditions is true:
1216 	 * - there are pending frames in software queue
1217 	 * - the TID is currently paused for ADDBA/BAR request
1218 	 * - seqno is not within block-ack window
1219 	 * - h/w queue depth exceeds low water mark
1220 	 */
1221 	if (!list_empty(&tid->buf_q) || tid->paused ||
1222 	    !BAW_WITHIN(tid->seq_start, tid->baw_size, bf->bf_seqno) ||
1223 	    txctl->txq->axq_depth >= ATH_AGGR_MIN_QDEPTH) {
1224 		/*
1225 		 * Add this frame to software queue for scheduling later
1226 		 * for aggregation.
1227 		 */
1228 		list_splice_tail_init(bf_head, &tid->buf_q);
1229 		ath_tx_queue_tid(txctl->txq, tid);
1230 		return 0;
1231 	}
1232 
1233 	/* Add sub-frame to BAW */
1234 	ath_tx_addto_baw(sc, tid, bf);
1235 
1236 	/* Queue to h/w without aggregation */
1237 	bf->bf_nframes = 1;
1238 	bf->bf_lastbf = bf->bf_lastfrm; /* one single frame */
1239 	ath_buf_set_rate(sc, bf);
1240 	ath_tx_txqaddbuf(sc, txctl->txq, bf_head);
1241 
1242 	return 0;
1243 }
1244 
1245 /*
1246  * looks up the rate
1247  * returns aggr limit based on lowest of the rates
1248  */
ath_lookup_rate(struct ath_softc * sc,struct ath_buf * bf,struct ath_atx_tid * tid)1249 static u32 ath_lookup_rate(struct ath_softc *sc,
1250 			   struct ath_buf *bf,
1251 			   struct ath_atx_tid *tid)
1252 {
1253 	struct ath_rate_table *rate_table = sc->cur_rate_table;
1254 	struct sk_buff *skb;
1255 	struct ieee80211_tx_info *tx_info;
1256 	struct ieee80211_tx_rate *rates;
1257 	struct ath_tx_info_priv *tx_info_priv;
1258 	u32 max_4ms_framelen, frame_length;
1259 	u16 aggr_limit, legacy = 0, maxampdu;
1260 	int i;
1261 
1262 	skb = (struct sk_buff *)bf->bf_mpdu;
1263 	tx_info = IEEE80211_SKB_CB(skb);
1264 	rates = tx_info->control.rates;
1265 	tx_info_priv =
1266 		(struct ath_tx_info_priv *)tx_info->rate_driver_data[0];
1267 
1268 	/*
1269 	 * Find the lowest frame length among the rate series that will have a
1270 	 * 4ms transmit duration.
1271 	 * TODO - TXOP limit needs to be considered.
1272 	 */
1273 	max_4ms_framelen = ATH_AMPDU_LIMIT_MAX;
1274 
1275 	for (i = 0; i < 4; i++) {
1276 		if (rates[i].count) {
1277 			if (!WLAN_RC_PHY_HT(rate_table->info[rates[i].idx].phy)) {
1278 				legacy = 1;
1279 				break;
1280 			}
1281 
1282 			frame_length =
1283 				rate_table->info[rates[i].idx].max_4ms_framelen;
1284 			max_4ms_framelen = min(max_4ms_framelen, frame_length);
1285 		}
1286 	}
1287 
1288 	/*
1289 	 * limit aggregate size by the minimum rate if rate selected is
1290 	 * not a probe rate, if rate selected is a probe rate then
1291 	 * avoid aggregation of this packet.
1292 	 */
1293 	if (tx_info->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE || legacy)
1294 		return 0;
1295 
1296 	aggr_limit = min(max_4ms_framelen,
1297 		(u32)ATH_AMPDU_LIMIT_DEFAULT);
1298 
1299 	/*
1300 	 * h/w can accept aggregates upto 16 bit lengths (65535).
1301 	 * The IE, however can hold upto 65536, which shows up here
1302 	 * as zero. Ignore 65536 since we  are constrained by hw.
1303 	 */
1304 	maxampdu = tid->an->maxampdu;
1305 	if (maxampdu)
1306 		aggr_limit = min(aggr_limit, maxampdu);
1307 
1308 	return aggr_limit;
1309 }
1310 
1311 /*
1312  * returns the number of delimiters to be added to
1313  * meet the minimum required mpdudensity.
1314  * caller should make sure that the rate is  HT rate .
1315  */
ath_compute_num_delims(struct ath_softc * sc,struct ath_atx_tid * tid,struct ath_buf * bf,u16 frmlen)1316 static int ath_compute_num_delims(struct ath_softc *sc,
1317 				  struct ath_atx_tid *tid,
1318 				  struct ath_buf *bf,
1319 				  u16 frmlen)
1320 {
1321 	struct ath_rate_table *rt = sc->cur_rate_table;
1322 	struct sk_buff *skb = bf->bf_mpdu;
1323 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1324 	u32 nsymbits, nsymbols, mpdudensity;
1325 	u16 minlen;
1326 	u8 rc, flags, rix;
1327 	int width, half_gi, ndelim, mindelim;
1328 
1329 	/* Select standard number of delimiters based on frame length alone */
1330 	ndelim = ATH_AGGR_GET_NDELIM(frmlen);
1331 
1332 	/*
1333 	 * If encryption enabled, hardware requires some more padding between
1334 	 * subframes.
1335 	 * TODO - this could be improved to be dependent on the rate.
1336 	 *      The hardware can keep up at lower rates, but not higher rates
1337 	 */
1338 	if (bf->bf_keytype != ATH9K_KEY_TYPE_CLEAR)
1339 		ndelim += ATH_AGGR_ENCRYPTDELIM;
1340 
1341 	/*
1342 	 * Convert desired mpdu density from microeconds to bytes based
1343 	 * on highest rate in rate series (i.e. first rate) to determine
1344 	 * required minimum length for subframe. Take into account
1345 	 * whether high rate is 20 or 40Mhz and half or full GI.
1346 	 */
1347 	mpdudensity = tid->an->mpdudensity;
1348 
1349 	/*
1350 	 * If there is no mpdu density restriction, no further calculation
1351 	 * is needed.
1352 	 */
1353 	if (mpdudensity == 0)
1354 		return ndelim;
1355 
1356 	rix = tx_info->control.rates[0].idx;
1357 	flags = tx_info->control.rates[0].flags;
1358 	rc = rt->info[rix].ratecode;
1359 	width = (flags & IEEE80211_TX_RC_40_MHZ_WIDTH) ? 1 : 0;
1360 	half_gi = (flags & IEEE80211_TX_RC_SHORT_GI) ? 1 : 0;
1361 
1362 	if (half_gi)
1363 		nsymbols = NUM_SYMBOLS_PER_USEC_HALFGI(mpdudensity);
1364 	else
1365 		nsymbols = NUM_SYMBOLS_PER_USEC(mpdudensity);
1366 
1367 	if (nsymbols == 0)
1368 		nsymbols = 1;
1369 
1370 	nsymbits = bits_per_symbol[HT_RC_2_MCS(rc)][width];
1371 	minlen = (nsymbols * nsymbits) / BITS_PER_BYTE;
1372 
1373 	/* Is frame shorter than required minimum length? */
1374 	if (frmlen < minlen) {
1375 		/* Get the minimum number of delimiters required. */
1376 		mindelim = (minlen - frmlen) / ATH_AGGR_DELIM_SZ;
1377 		ndelim = max(mindelim, ndelim);
1378 	}
1379 
1380 	return ndelim;
1381 }
1382 
1383 /*
1384  * For aggregation from software buffer queue.
1385  * NB: must be called with txq lock held
1386  */
ath_tx_form_aggr(struct ath_softc * sc,struct ath_atx_tid * tid,struct list_head * bf_q,struct ath_buf ** bf_last,struct aggr_rifs_param * param,int * prev_frames)1387 static enum ATH_AGGR_STATUS ath_tx_form_aggr(struct ath_softc *sc,
1388 					struct ath_atx_tid *tid,
1389 					struct list_head *bf_q,
1390 					struct ath_buf **bf_last,
1391 					struct aggr_rifs_param *param,
1392 					int *prev_frames)
1393 {
1394 #define PADBYTES(_len) ((4 - ((_len) % 4)) % 4)
1395 	struct ath_buf *bf, *tbf, *bf_first, *bf_prev = NULL;
1396 	struct list_head bf_head;
1397 	int rl = 0, nframes = 0, ndelim;
1398 	u16 aggr_limit = 0, al = 0, bpad = 0,
1399 		al_delta, h_baw = tid->baw_size / 2;
1400 	enum ATH_AGGR_STATUS status = ATH_AGGR_DONE;
1401 	int prev_al = 0;
1402 	INIT_LIST_HEAD(&bf_head);
1403 
1404 	BUG_ON(list_empty(&tid->buf_q));
1405 
1406 	bf_first = list_first_entry(&tid->buf_q, struct ath_buf, list);
1407 
1408 	do {
1409 		bf = list_first_entry(&tid->buf_q, struct ath_buf, list);
1410 
1411 		/*
1412 		 * do not step over block-ack window
1413 		 */
1414 		if (!BAW_WITHIN(tid->seq_start, tid->baw_size, bf->bf_seqno)) {
1415 			status = ATH_AGGR_BAW_CLOSED;
1416 			break;
1417 		}
1418 
1419 		if (!rl) {
1420 			aggr_limit = ath_lookup_rate(sc, bf, tid);
1421 			rl = 1;
1422 		}
1423 
1424 		/*
1425 		 * do not exceed aggregation limit
1426 		 */
1427 		al_delta = ATH_AGGR_DELIM_SZ + bf->bf_frmlen;
1428 
1429 		if (nframes && (aggr_limit <
1430 			(al + bpad + al_delta + prev_al))) {
1431 			status = ATH_AGGR_LIMITED;
1432 			break;
1433 		}
1434 
1435 		/*
1436 		 * do not exceed subframe limit
1437 		 */
1438 		if ((nframes + *prev_frames) >=
1439 		    min((int)h_baw, ATH_AMPDU_SUBFRAME_DEFAULT)) {
1440 			status = ATH_AGGR_LIMITED;
1441 			break;
1442 		}
1443 
1444 		/*
1445 		 * add padding for previous frame to aggregation length
1446 		 */
1447 		al += bpad + al_delta;
1448 
1449 		/*
1450 		 * Get the delimiters needed to meet the MPDU
1451 		 * density for this node.
1452 		 */
1453 		ndelim = ath_compute_num_delims(sc, tid, bf_first, bf->bf_frmlen);
1454 
1455 		bpad = PADBYTES(al_delta) + (ndelim << 2);
1456 
1457 		bf->bf_next = NULL;
1458 		bf->bf_lastfrm->bf_desc->ds_link = 0;
1459 
1460 		/*
1461 		 * this packet is part of an aggregate
1462 		 * - remove all descriptors belonging to this frame from
1463 		 *   software queue
1464 		 * - add it to block ack window
1465 		 * - set up descriptors for aggregation
1466 		 */
1467 		list_cut_position(&bf_head, &tid->buf_q, &bf->bf_lastfrm->list);
1468 		ath_tx_addto_baw(sc, tid, bf);
1469 
1470 		list_for_each_entry(tbf, &bf_head, list) {
1471 			ath9k_hw_set11n_aggr_middle(sc->sc_ah,
1472 				tbf->bf_desc, ndelim);
1473 		}
1474 
1475 		/*
1476 		 * link buffers of this frame to the aggregate
1477 		 */
1478 		list_splice_tail_init(&bf_head, bf_q);
1479 		nframes++;
1480 
1481 		if (bf_prev) {
1482 			bf_prev->bf_next = bf;
1483 			bf_prev->bf_lastfrm->bf_desc->ds_link = bf->bf_daddr;
1484 		}
1485 		bf_prev = bf;
1486 
1487 #ifdef AGGR_NOSHORT
1488 		/*
1489 		 * terminate aggregation on a small packet boundary
1490 		 */
1491 		if (bf->bf_frmlen < ATH_AGGR_MINPLEN) {
1492 			status = ATH_AGGR_SHORTPKT;
1493 			break;
1494 		}
1495 #endif
1496 	} while (!list_empty(&tid->buf_q));
1497 
1498 	bf_first->bf_al = al;
1499 	bf_first->bf_nframes = nframes;
1500 	*bf_last = bf_prev;
1501 	return status;
1502 #undef PADBYTES
1503 }
1504 
1505 /*
1506  * process pending frames possibly doing a-mpdu aggregation
1507  * NB: must be called with txq lock held
1508  */
ath_tx_sched_aggr(struct ath_softc * sc,struct ath_txq * txq,struct ath_atx_tid * tid)1509 static void ath_tx_sched_aggr(struct ath_softc *sc,
1510 	struct ath_txq *txq, struct ath_atx_tid *tid)
1511 {
1512 	struct ath_buf *bf, *tbf, *bf_last, *bf_lastaggr = NULL;
1513 	enum ATH_AGGR_STATUS status;
1514 	struct list_head bf_q;
1515 	struct aggr_rifs_param param = {0, 0, 0, 0, NULL};
1516 	int prev_frames = 0;
1517 
1518 	do {
1519 		if (list_empty(&tid->buf_q))
1520 			return;
1521 
1522 		INIT_LIST_HEAD(&bf_q);
1523 
1524 		status = ath_tx_form_aggr(sc, tid, &bf_q, &bf_lastaggr, &param,
1525 					  &prev_frames);
1526 
1527 		/*
1528 		 * no frames picked up to be aggregated; block-ack
1529 		 * window is not open
1530 		 */
1531 		if (list_empty(&bf_q))
1532 			break;
1533 
1534 		bf = list_first_entry(&bf_q, struct ath_buf, list);
1535 		bf_last = list_entry(bf_q.prev, struct ath_buf, list);
1536 		bf->bf_lastbf = bf_last;
1537 
1538 		/*
1539 		 * if only one frame, send as non-aggregate
1540 		 */
1541 		if (bf->bf_nframes == 1) {
1542 			ASSERT(bf->bf_lastfrm == bf_last);
1543 
1544 			bf->bf_state.bf_type &= ~BUF_AGGR;
1545 			/*
1546 			 * clear aggr bits for every descriptor
1547 			 * XXX TODO: is there a way to optimize it?
1548 			 */
1549 			list_for_each_entry(tbf, &bf_q, list) {
1550 				ath9k_hw_clr11n_aggr(sc->sc_ah, tbf->bf_desc);
1551 			}
1552 
1553 			ath_buf_set_rate(sc, bf);
1554 			ath_tx_txqaddbuf(sc, txq, &bf_q);
1555 			continue;
1556 		}
1557 
1558 		/*
1559 		 * setup first desc with rate and aggr info
1560 		 */
1561 		bf->bf_state.bf_type |= BUF_AGGR;
1562 		ath_buf_set_rate(sc, bf);
1563 		ath9k_hw_set11n_aggr_first(sc->sc_ah, bf->bf_desc, bf->bf_al);
1564 
1565 		/*
1566 		 * anchor last frame of aggregate correctly
1567 		 */
1568 		ASSERT(bf_lastaggr);
1569 		ASSERT(bf_lastaggr->bf_lastfrm == bf_last);
1570 		tbf = bf_lastaggr;
1571 		ath9k_hw_set11n_aggr_last(sc->sc_ah, tbf->bf_desc);
1572 
1573 		/* XXX: We don't enter into this loop, consider removing this */
1574 		while (!list_empty(&bf_q) && !list_is_last(&tbf->list, &bf_q)) {
1575 			tbf = list_entry(tbf->list.next, struct ath_buf, list);
1576 			ath9k_hw_set11n_aggr_last(sc->sc_ah, tbf->bf_desc);
1577 		}
1578 
1579 		txq->axq_aggr_depth++;
1580 
1581 		/*
1582 		 * Normal aggregate, queue to hardware
1583 		 */
1584 		ath_tx_txqaddbuf(sc, txq, &bf_q);
1585 
1586 	} while (txq->axq_depth < ATH_AGGR_MIN_QDEPTH &&
1587 		 status != ATH_AGGR_BAW_CLOSED);
1588 }
1589 
1590 /* Called with txq lock held */
1591 
ath_tid_drain(struct ath_softc * sc,struct ath_txq * txq,struct ath_atx_tid * tid)1592 static void ath_tid_drain(struct ath_softc *sc,
1593 			  struct ath_txq *txq,
1594 			  struct ath_atx_tid *tid)
1595 
1596 {
1597 	struct ath_buf *bf;
1598 	struct list_head bf_head;
1599 	INIT_LIST_HEAD(&bf_head);
1600 
1601 	for (;;) {
1602 		if (list_empty(&tid->buf_q))
1603 			break;
1604 		bf = list_first_entry(&tid->buf_q, struct ath_buf, list);
1605 
1606 		list_cut_position(&bf_head, &tid->buf_q, &bf->bf_lastfrm->list);
1607 
1608 		/* update baw for software retried frame */
1609 		if (bf_isretried(bf))
1610 			ath_tx_update_baw(sc, tid, bf->bf_seqno);
1611 
1612 		/*
1613 		 * do not indicate packets while holding txq spinlock.
1614 		 * unlock is intentional here
1615 		 */
1616 		spin_unlock(&txq->axq_lock);
1617 
1618 		/* complete this sub-frame */
1619 		ath_tx_complete_buf(sc, bf, &bf_head, 0, 0);
1620 
1621 		spin_lock(&txq->axq_lock);
1622 	}
1623 
1624 	/*
1625 	 * TODO: For frame(s) that are in the retry state, we will reuse the
1626 	 * sequence number(s) without setting the retry bit. The
1627 	 * alternative is to give up on these and BAR the receiver's window
1628 	 * forward.
1629 	 */
1630 	tid->seq_next = tid->seq_start;
1631 	tid->baw_tail = tid->baw_head;
1632 }
1633 
1634 /*
1635  * Drain all pending buffers
1636  * NB: must be called with txq lock held
1637  */
ath_txq_drain_pending_buffers(struct ath_softc * sc,struct ath_txq * txq)1638 static void ath_txq_drain_pending_buffers(struct ath_softc *sc,
1639 					  struct ath_txq *txq)
1640 {
1641 	struct ath_atx_ac *ac, *ac_tmp;
1642 	struct ath_atx_tid *tid, *tid_tmp;
1643 
1644 	list_for_each_entry_safe(ac, ac_tmp, &txq->axq_acq, list) {
1645 		list_del(&ac->list);
1646 		ac->sched = false;
1647 		list_for_each_entry_safe(tid, tid_tmp, &ac->tid_q, list) {
1648 			list_del(&tid->list);
1649 			tid->sched = false;
1650 			ath_tid_drain(sc, txq, tid);
1651 		}
1652 	}
1653 }
1654 
ath_tx_setup_buffer(struct ath_softc * sc,struct ath_buf * bf,struct sk_buff * skb,struct ath_tx_control * txctl)1655 static int ath_tx_setup_buffer(struct ath_softc *sc, struct ath_buf *bf,
1656 				struct sk_buff *skb,
1657 				struct ath_tx_control *txctl)
1658 {
1659 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
1660 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
1661 	struct ath_tx_info_priv *tx_info_priv;
1662 	int hdrlen;
1663 	__le16 fc;
1664 
1665 	tx_info_priv = kzalloc(sizeof(*tx_info_priv), GFP_ATOMIC);
1666 	if (unlikely(!tx_info_priv))
1667 		return -ENOMEM;
1668 	tx_info->rate_driver_data[0] = tx_info_priv;
1669 	hdrlen = ieee80211_get_hdrlen_from_skb(skb);
1670 	fc = hdr->frame_control;
1671 
1672 	ATH_TXBUF_RESET(bf);
1673 
1674 	/* Frame type */
1675 
1676 	bf->bf_frmlen = skb->len + FCS_LEN - (hdrlen & 3);
1677 
1678 	ieee80211_is_data(fc) ?
1679 		(bf->bf_state.bf_type |= BUF_DATA) :
1680 		(bf->bf_state.bf_type &= ~BUF_DATA);
1681 	ieee80211_is_back_req(fc) ?
1682 		(bf->bf_state.bf_type |= BUF_BAR) :
1683 		(bf->bf_state.bf_type &= ~BUF_BAR);
1684 	ieee80211_is_pspoll(fc) ?
1685 		(bf->bf_state.bf_type |= BUF_PSPOLL) :
1686 		(bf->bf_state.bf_type &= ~BUF_PSPOLL);
1687 	(sc->sc_flags & SC_OP_PREAMBLE_SHORT) ?
1688 		(bf->bf_state.bf_type |= BUF_SHORT_PREAMBLE) :
1689 		(bf->bf_state.bf_type &= ~BUF_SHORT_PREAMBLE);
1690 	(sc->hw->conf.ht.enabled && !is_pae(skb) &&
1691 	 (tx_info->flags & IEEE80211_TX_CTL_AMPDU)) ?
1692 		(bf->bf_state.bf_type |= BUF_HT) :
1693 		(bf->bf_state.bf_type &= ~BUF_HT);
1694 
1695 	bf->bf_flags = setup_tx_flags(sc, skb, txctl->txq);
1696 
1697 	/* Crypto */
1698 
1699 	bf->bf_keytype = get_hw_crypto_keytype(skb);
1700 
1701 	if (bf->bf_keytype != ATH9K_KEY_TYPE_CLEAR) {
1702 		bf->bf_frmlen += tx_info->control.hw_key->icv_len;
1703 		bf->bf_keyix = tx_info->control.hw_key->hw_key_idx;
1704 	} else {
1705 		bf->bf_keyix = ATH9K_TXKEYIX_INVALID;
1706 	}
1707 
1708 	/* Assign seqno, tidno */
1709 
1710 	if (ieee80211_is_data_qos(fc) && (sc->sc_flags & SC_OP_TXAGGR))
1711 		assign_aggr_tid_seqno(skb, bf);
1712 
1713 	/* DMA setup */
1714 	bf->bf_mpdu = skb;
1715 
1716 	bf->bf_dmacontext = pci_map_single(sc->pdev, skb->data,
1717 					   skb->len, PCI_DMA_TODEVICE);
1718 	if (unlikely(pci_dma_mapping_error(sc->pdev, bf->bf_dmacontext))) {
1719 		bf->bf_mpdu = NULL;
1720 		DPRINTF(sc, ATH_DBG_CONFIG,
1721 			"pci_dma_mapping_error() on TX\n");
1722 		return -ENOMEM;
1723 	}
1724 
1725 	bf->bf_buf_addr = bf->bf_dmacontext;
1726 	return 0;
1727 }
1728 
1729 /* FIXME: tx power */
ath_tx_start_dma(struct ath_softc * sc,struct ath_buf * bf,struct ath_tx_control * txctl)1730 static void ath_tx_start_dma(struct ath_softc *sc, struct ath_buf *bf,
1731 			     struct ath_tx_control *txctl)
1732 {
1733 	struct sk_buff *skb = (struct sk_buff *)bf->bf_mpdu;
1734 	struct ieee80211_tx_info *tx_info =  IEEE80211_SKB_CB(skb);
1735 	struct ath_node *an = NULL;
1736 	struct list_head bf_head;
1737 	struct ath_desc *ds;
1738 	struct ath_atx_tid *tid;
1739 	struct ath_hal *ah = sc->sc_ah;
1740 	int frm_type;
1741 
1742 	frm_type = get_hw_packet_type(skb);
1743 
1744 	INIT_LIST_HEAD(&bf_head);
1745 	list_add_tail(&bf->list, &bf_head);
1746 
1747 	/* setup descriptor */
1748 
1749 	ds = bf->bf_desc;
1750 	ds->ds_link = 0;
1751 	ds->ds_data = bf->bf_buf_addr;
1752 
1753 	/* Formulate first tx descriptor with tx controls */
1754 
1755 	ath9k_hw_set11n_txdesc(ah, ds, bf->bf_frmlen, frm_type, MAX_RATE_POWER,
1756 			       bf->bf_keyix, bf->bf_keytype, bf->bf_flags);
1757 
1758 	ath9k_hw_filltxdesc(ah, ds,
1759 			    skb->len,	/* segment length */
1760 			    true,	/* first segment */
1761 			    true,	/* last segment */
1762 			    ds);	/* first descriptor */
1763 
1764 	bf->bf_lastfrm = bf;
1765 
1766 	spin_lock_bh(&txctl->txq->axq_lock);
1767 
1768 	if (bf_isht(bf) && (sc->sc_flags & SC_OP_TXAGGR) &&
1769 	    tx_info->control.sta) {
1770 		an = (struct ath_node *)tx_info->control.sta->drv_priv;
1771 		tid = ATH_AN_2_TID(an, bf->bf_tidno);
1772 
1773 		if (ath_aggr_query(sc, an, bf->bf_tidno)) {
1774 			/*
1775 			 * Try aggregation if it's a unicast data frame
1776 			 * and the destination is HT capable.
1777 			 */
1778 			ath_tx_send_ampdu(sc, tid, &bf_head, txctl);
1779 		} else {
1780 			/*
1781 			 * Send this frame as regular when ADDBA
1782 			 * exchange is neither complete nor pending.
1783 			 */
1784 			ath_tx_send_normal(sc, txctl->txq,
1785 					   tid, &bf_head);
1786 		}
1787 	} else {
1788 		bf->bf_lastbf = bf;
1789 		bf->bf_nframes = 1;
1790 
1791 		ath_buf_set_rate(sc, bf);
1792 		ath_tx_txqaddbuf(sc, txctl->txq, &bf_head);
1793 	}
1794 
1795 	spin_unlock_bh(&txctl->txq->axq_lock);
1796 }
1797 
1798 /* Upon failure caller should free skb */
ath_tx_start(struct ath_softc * sc,struct sk_buff * skb,struct ath_tx_control * txctl)1799 int ath_tx_start(struct ath_softc *sc, struct sk_buff *skb,
1800 		 struct ath_tx_control *txctl)
1801 {
1802 	struct ath_buf *bf;
1803 	int r;
1804 
1805 	/* Check if a tx buffer is available */
1806 
1807 	bf = ath_tx_get_buffer(sc);
1808 	if (!bf) {
1809 		DPRINTF(sc, ATH_DBG_XMIT, "TX buffers are full\n");
1810 		return -1;
1811 	}
1812 
1813 	r = ath_tx_setup_buffer(sc, bf, skb, txctl);
1814 	if (unlikely(r)) {
1815 		struct ath_txq *txq = txctl->txq;
1816 
1817 		DPRINTF(sc, ATH_DBG_FATAL, "TX mem alloc failure\n");
1818 
1819 		/* upon ath_tx_processq() this TX queue will be resumed, we
1820 		 * guarantee this will happen by knowing beforehand that
1821 		 * we will at least have to run TX completionon one buffer
1822 		 * on the queue */
1823 		spin_lock_bh(&txq->axq_lock);
1824 		if (ath_txq_depth(sc, txq->axq_qnum) > 1) {
1825 			ieee80211_stop_queue(sc->hw,
1826 				skb_get_queue_mapping(skb));
1827 			txq->stopped = 1;
1828 		}
1829 		spin_unlock_bh(&txq->axq_lock);
1830 
1831 		spin_lock_bh(&sc->tx.txbuflock);
1832 		list_add_tail(&bf->list, &sc->tx.txbuf);
1833 		spin_unlock_bh(&sc->tx.txbuflock);
1834 
1835 		return r;
1836 	}
1837 
1838 	ath_tx_start_dma(sc, bf, txctl);
1839 
1840 	return 0;
1841 }
1842 
1843 /* Initialize TX queue and h/w */
1844 
ath_tx_init(struct ath_softc * sc,int nbufs)1845 int ath_tx_init(struct ath_softc *sc, int nbufs)
1846 {
1847 	int error = 0;
1848 
1849 	do {
1850 		spin_lock_init(&sc->tx.txbuflock);
1851 
1852 		/* Setup tx descriptors */
1853 		error = ath_descdma_setup(sc, &sc->tx.txdma, &sc->tx.txbuf,
1854 			"tx", nbufs, 1);
1855 		if (error != 0) {
1856 			DPRINTF(sc, ATH_DBG_FATAL,
1857 				"Failed to allocate tx descriptors: %d\n",
1858 				error);
1859 			break;
1860 		}
1861 
1862 		/* XXX allocate beacon state together with vap */
1863 		error = ath_descdma_setup(sc, &sc->beacon.bdma, &sc->beacon.bbuf,
1864 					  "beacon", ATH_BCBUF, 1);
1865 		if (error != 0) {
1866 			DPRINTF(sc, ATH_DBG_FATAL,
1867 				"Failed to allocate beacon descriptors: %d\n",
1868 				error);
1869 			break;
1870 		}
1871 
1872 	} while (0);
1873 
1874 	if (error != 0)
1875 		ath_tx_cleanup(sc);
1876 
1877 	return error;
1878 }
1879 
1880 /* Reclaim all tx queue resources */
1881 
ath_tx_cleanup(struct ath_softc * sc)1882 int ath_tx_cleanup(struct ath_softc *sc)
1883 {
1884 	/* cleanup beacon descriptors */
1885 	if (sc->beacon.bdma.dd_desc_len != 0)
1886 		ath_descdma_cleanup(sc, &sc->beacon.bdma, &sc->beacon.bbuf);
1887 
1888 	/* cleanup tx descriptors */
1889 	if (sc->tx.txdma.dd_desc_len != 0)
1890 		ath_descdma_cleanup(sc, &sc->tx.txdma, &sc->tx.txbuf);
1891 
1892 	return 0;
1893 }
1894 
1895 /* Setup a h/w transmit queue */
1896 
ath_txq_setup(struct ath_softc * sc,int qtype,int subtype)1897 struct ath_txq *ath_txq_setup(struct ath_softc *sc, int qtype, int subtype)
1898 {
1899 	struct ath_hal *ah = sc->sc_ah;
1900 	struct ath9k_tx_queue_info qi;
1901 	int qnum;
1902 
1903 	memset(&qi, 0, sizeof(qi));
1904 	qi.tqi_subtype = subtype;
1905 	qi.tqi_aifs = ATH9K_TXQ_USEDEFAULT;
1906 	qi.tqi_cwmin = ATH9K_TXQ_USEDEFAULT;
1907 	qi.tqi_cwmax = ATH9K_TXQ_USEDEFAULT;
1908 	qi.tqi_physCompBuf = 0;
1909 
1910 	/*
1911 	 * Enable interrupts only for EOL and DESC conditions.
1912 	 * We mark tx descriptors to receive a DESC interrupt
1913 	 * when a tx queue gets deep; otherwise waiting for the
1914 	 * EOL to reap descriptors.  Note that this is done to
1915 	 * reduce interrupt load and this only defers reaping
1916 	 * descriptors, never transmitting frames.  Aside from
1917 	 * reducing interrupts this also permits more concurrency.
1918 	 * The only potential downside is if the tx queue backs
1919 	 * up in which case the top half of the kernel may backup
1920 	 * due to a lack of tx descriptors.
1921 	 *
1922 	 * The UAPSD queue is an exception, since we take a desc-
1923 	 * based intr on the EOSP frames.
1924 	 */
1925 	if (qtype == ATH9K_TX_QUEUE_UAPSD)
1926 		qi.tqi_qflags = TXQ_FLAG_TXDESCINT_ENABLE;
1927 	else
1928 		qi.tqi_qflags = TXQ_FLAG_TXEOLINT_ENABLE |
1929 			TXQ_FLAG_TXDESCINT_ENABLE;
1930 	qnum = ath9k_hw_setuptxqueue(ah, qtype, &qi);
1931 	if (qnum == -1) {
1932 		/*
1933 		 * NB: don't print a message, this happens
1934 		 * normally on parts with too few tx queues
1935 		 */
1936 		return NULL;
1937 	}
1938 	if (qnum >= ARRAY_SIZE(sc->tx.txq)) {
1939 		DPRINTF(sc, ATH_DBG_FATAL,
1940 			"qnum %u out of range, max %u!\n",
1941 			qnum, (unsigned int)ARRAY_SIZE(sc->tx.txq));
1942 		ath9k_hw_releasetxqueue(ah, qnum);
1943 		return NULL;
1944 	}
1945 	if (!ATH_TXQ_SETUP(sc, qnum)) {
1946 		struct ath_txq *txq = &sc->tx.txq[qnum];
1947 
1948 		txq->axq_qnum = qnum;
1949 		txq->axq_link = NULL;
1950 		INIT_LIST_HEAD(&txq->axq_q);
1951 		INIT_LIST_HEAD(&txq->axq_acq);
1952 		spin_lock_init(&txq->axq_lock);
1953 		txq->axq_depth = 0;
1954 		txq->axq_aggr_depth = 0;
1955 		txq->axq_totalqueued = 0;
1956 		txq->axq_linkbuf = NULL;
1957 		sc->tx.txqsetup |= 1<<qnum;
1958 	}
1959 	return &sc->tx.txq[qnum];
1960 }
1961 
1962 /* Reclaim resources for a setup queue */
1963 
ath_tx_cleanupq(struct ath_softc * sc,struct ath_txq * txq)1964 void ath_tx_cleanupq(struct ath_softc *sc, struct ath_txq *txq)
1965 {
1966 	ath9k_hw_releasetxqueue(sc->sc_ah, txq->axq_qnum);
1967 	sc->tx.txqsetup &= ~(1<<txq->axq_qnum);
1968 }
1969 
1970 /*
1971  * Setup a hardware data transmit queue for the specified
1972  * access control.  The hal may not support all requested
1973  * queues in which case it will return a reference to a
1974  * previously setup queue.  We record the mapping from ac's
1975  * to h/w queues for use by ath_tx_start and also track
1976  * the set of h/w queues being used to optimize work in the
1977  * transmit interrupt handler and related routines.
1978  */
1979 
ath_tx_setup(struct ath_softc * sc,int haltype)1980 int ath_tx_setup(struct ath_softc *sc, int haltype)
1981 {
1982 	struct ath_txq *txq;
1983 
1984 	if (haltype >= ARRAY_SIZE(sc->tx.hwq_map)) {
1985 		DPRINTF(sc, ATH_DBG_FATAL,
1986 			"HAL AC %u out of range, max %zu!\n",
1987 			 haltype, ARRAY_SIZE(sc->tx.hwq_map));
1988 		return 0;
1989 	}
1990 	txq = ath_txq_setup(sc, ATH9K_TX_QUEUE_DATA, haltype);
1991 	if (txq != NULL) {
1992 		sc->tx.hwq_map[haltype] = txq->axq_qnum;
1993 		return 1;
1994 	} else
1995 		return 0;
1996 }
1997 
ath_tx_get_qnum(struct ath_softc * sc,int qtype,int haltype)1998 int ath_tx_get_qnum(struct ath_softc *sc, int qtype, int haltype)
1999 {
2000 	int qnum;
2001 
2002 	switch (qtype) {
2003 	case ATH9K_TX_QUEUE_DATA:
2004 		if (haltype >= ARRAY_SIZE(sc->tx.hwq_map)) {
2005 			DPRINTF(sc, ATH_DBG_FATAL,
2006 				"HAL AC %u out of range, max %zu!\n",
2007 				haltype, ARRAY_SIZE(sc->tx.hwq_map));
2008 			return -1;
2009 		}
2010 		qnum = sc->tx.hwq_map[haltype];
2011 		break;
2012 	case ATH9K_TX_QUEUE_BEACON:
2013 		qnum = sc->beacon.beaconq;
2014 		break;
2015 	case ATH9K_TX_QUEUE_CAB:
2016 		qnum = sc->beacon.cabq->axq_qnum;
2017 		break;
2018 	default:
2019 		qnum = -1;
2020 	}
2021 	return qnum;
2022 }
2023 
2024 /* Get a transmit queue, if available */
2025 
ath_test_get_txq(struct ath_softc * sc,struct sk_buff * skb)2026 struct ath_txq *ath_test_get_txq(struct ath_softc *sc, struct sk_buff *skb)
2027 {
2028 	struct ath_txq *txq = NULL;
2029 	int qnum;
2030 
2031 	qnum = ath_get_hal_qnum(skb_get_queue_mapping(skb), sc);
2032 	txq = &sc->tx.txq[qnum];
2033 
2034 	spin_lock_bh(&txq->axq_lock);
2035 
2036 	/* Try to avoid running out of descriptors */
2037 	if (txq->axq_depth >= (ATH_TXBUF - 20)) {
2038 		DPRINTF(sc, ATH_DBG_FATAL,
2039 			"TX queue: %d is full, depth: %d\n",
2040 			qnum, txq->axq_depth);
2041 		ieee80211_stop_queue(sc->hw, skb_get_queue_mapping(skb));
2042 		txq->stopped = 1;
2043 		spin_unlock_bh(&txq->axq_lock);
2044 		return NULL;
2045 	}
2046 
2047 	spin_unlock_bh(&txq->axq_lock);
2048 
2049 	return txq;
2050 }
2051 
2052 /* Update parameters for a transmit queue */
2053 
ath_txq_update(struct ath_softc * sc,int qnum,struct ath9k_tx_queue_info * qinfo)2054 int ath_txq_update(struct ath_softc *sc, int qnum,
2055 		   struct ath9k_tx_queue_info *qinfo)
2056 {
2057 	struct ath_hal *ah = sc->sc_ah;
2058 	int error = 0;
2059 	struct ath9k_tx_queue_info qi;
2060 
2061 	if (qnum == sc->beacon.beaconq) {
2062 		/*
2063 		 * XXX: for beacon queue, we just save the parameter.
2064 		 * It will be picked up by ath_beaconq_config when
2065 		 * it's necessary.
2066 		 */
2067 		sc->beacon.beacon_qi = *qinfo;
2068 		return 0;
2069 	}
2070 
2071 	ASSERT(sc->tx.txq[qnum].axq_qnum == qnum);
2072 
2073 	ath9k_hw_get_txq_props(ah, qnum, &qi);
2074 	qi.tqi_aifs = qinfo->tqi_aifs;
2075 	qi.tqi_cwmin = qinfo->tqi_cwmin;
2076 	qi.tqi_cwmax = qinfo->tqi_cwmax;
2077 	qi.tqi_burstTime = qinfo->tqi_burstTime;
2078 	qi.tqi_readyTime = qinfo->tqi_readyTime;
2079 
2080 	if (!ath9k_hw_set_txq_props(ah, qnum, &qi)) {
2081 		DPRINTF(sc, ATH_DBG_FATAL,
2082 			"Unable to update hardware queue %u!\n", qnum);
2083 		error = -EIO;
2084 	} else {
2085 		ath9k_hw_resettxqueue(ah, qnum); /* push to h/w */
2086 	}
2087 
2088 	return error;
2089 }
2090 
ath_cabq_update(struct ath_softc * sc)2091 int ath_cabq_update(struct ath_softc *sc)
2092 {
2093 	struct ath9k_tx_queue_info qi;
2094 	int qnum = sc->beacon.cabq->axq_qnum;
2095 	struct ath_beacon_config conf;
2096 
2097 	ath9k_hw_get_txq_props(sc->sc_ah, qnum, &qi);
2098 	/*
2099 	 * Ensure the readytime % is within the bounds.
2100 	 */
2101 	if (sc->sc_config.cabqReadytime < ATH9K_READY_TIME_LO_BOUND)
2102 		sc->sc_config.cabqReadytime = ATH9K_READY_TIME_LO_BOUND;
2103 	else if (sc->sc_config.cabqReadytime > ATH9K_READY_TIME_HI_BOUND)
2104 		sc->sc_config.cabqReadytime = ATH9K_READY_TIME_HI_BOUND;
2105 
2106 	ath_get_beaconconfig(sc, ATH_IF_ID_ANY, &conf);
2107 	qi.tqi_readyTime =
2108 		(conf.beacon_interval * sc->sc_config.cabqReadytime) / 100;
2109 	ath_txq_update(sc, qnum, &qi);
2110 
2111 	return 0;
2112 }
2113 
2114 /* Deferred processing of transmit interrupt */
2115 
ath_tx_tasklet(struct ath_softc * sc)2116 void ath_tx_tasklet(struct ath_softc *sc)
2117 {
2118 	int i;
2119 	u32 qcumask = ((1 << ATH9K_NUM_TX_QUEUES) - 1);
2120 
2121 	ath9k_hw_gettxintrtxqs(sc->sc_ah, &qcumask);
2122 
2123 	/*
2124 	 * Process each active queue.
2125 	 */
2126 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
2127 		if (ATH_TXQ_SETUP(sc, i) && (qcumask & (1 << i)))
2128 			ath_tx_processq(sc, &sc->tx.txq[i]);
2129 	}
2130 }
2131 
ath_tx_draintxq(struct ath_softc * sc,struct ath_txq * txq,bool retry_tx)2132 void ath_tx_draintxq(struct ath_softc *sc,
2133 	struct ath_txq *txq, bool retry_tx)
2134 {
2135 	struct ath_buf *bf, *lastbf;
2136 	struct list_head bf_head;
2137 
2138 	INIT_LIST_HEAD(&bf_head);
2139 
2140 	/*
2141 	 * NB: this assumes output has been stopped and
2142 	 *     we do not need to block ath_tx_tasklet
2143 	 */
2144 	for (;;) {
2145 		spin_lock_bh(&txq->axq_lock);
2146 
2147 		if (list_empty(&txq->axq_q)) {
2148 			txq->axq_link = NULL;
2149 			txq->axq_linkbuf = NULL;
2150 			spin_unlock_bh(&txq->axq_lock);
2151 			break;
2152 		}
2153 
2154 		bf = list_first_entry(&txq->axq_q, struct ath_buf, list);
2155 
2156 		if (bf->bf_status & ATH_BUFSTATUS_STALE) {
2157 			list_del(&bf->list);
2158 			spin_unlock_bh(&txq->axq_lock);
2159 
2160 			spin_lock_bh(&sc->tx.txbuflock);
2161 			list_add_tail(&bf->list, &sc->tx.txbuf);
2162 			spin_unlock_bh(&sc->tx.txbuflock);
2163 			continue;
2164 		}
2165 
2166 		lastbf = bf->bf_lastbf;
2167 		if (!retry_tx)
2168 			lastbf->bf_desc->ds_txstat.ts_flags =
2169 				ATH9K_TX_SW_ABORTED;
2170 
2171 		/* remove ath_buf's of the same mpdu from txq */
2172 		list_cut_position(&bf_head, &txq->axq_q, &lastbf->list);
2173 		txq->axq_depth--;
2174 
2175 		spin_unlock_bh(&txq->axq_lock);
2176 
2177 		if (bf_isampdu(bf))
2178 			ath_tx_complete_aggr_rifs(sc, txq, bf, &bf_head, 0);
2179 		else
2180 			ath_tx_complete_buf(sc, bf, &bf_head, 0, 0);
2181 	}
2182 
2183 	/* flush any pending frames if aggregation is enabled */
2184 	if (sc->sc_flags & SC_OP_TXAGGR) {
2185 		if (!retry_tx) {
2186 			spin_lock_bh(&txq->axq_lock);
2187 			ath_txq_drain_pending_buffers(sc, txq);
2188 			spin_unlock_bh(&txq->axq_lock);
2189 		}
2190 	}
2191 }
2192 
2193 /* Drain the transmit queues and reclaim resources */
2194 
ath_draintxq(struct ath_softc * sc,bool retry_tx)2195 void ath_draintxq(struct ath_softc *sc, bool retry_tx)
2196 {
2197 	/* stop beacon queue. The beacon will be freed when
2198 	 * we go to INIT state */
2199 	if (!(sc->sc_flags & SC_OP_INVALID)) {
2200 		(void) ath9k_hw_stoptxdma(sc->sc_ah, sc->beacon.beaconq);
2201 		DPRINTF(sc, ATH_DBG_XMIT, "beacon queue %x\n",
2202 			ath9k_hw_gettxbuf(sc->sc_ah, sc->beacon.beaconq));
2203 	}
2204 
2205 	ath_drain_txdataq(sc, retry_tx);
2206 }
2207 
ath_txq_depth(struct ath_softc * sc,int qnum)2208 u32 ath_txq_depth(struct ath_softc *sc, int qnum)
2209 {
2210 	return sc->tx.txq[qnum].axq_depth;
2211 }
2212 
ath_txq_aggr_depth(struct ath_softc * sc,int qnum)2213 u32 ath_txq_aggr_depth(struct ath_softc *sc, int qnum)
2214 {
2215 	return sc->tx.txq[qnum].axq_aggr_depth;
2216 }
2217 
ath_tx_aggr_check(struct ath_softc * sc,struct ath_node * an,u8 tidno)2218 bool ath_tx_aggr_check(struct ath_softc *sc, struct ath_node *an, u8 tidno)
2219 {
2220 	struct ath_atx_tid *txtid;
2221 
2222 	if (!(sc->sc_flags & SC_OP_TXAGGR))
2223 		return false;
2224 
2225 	txtid = ATH_AN_2_TID(an, tidno);
2226 
2227 	if (!(txtid->state & AGGR_ADDBA_COMPLETE)) {
2228 		if (!(txtid->state & AGGR_ADDBA_PROGRESS) &&
2229 		    (txtid->addba_exchangeattempts < ADDBA_EXCHANGE_ATTEMPTS)) {
2230 			txtid->addba_exchangeattempts++;
2231 			return true;
2232 		}
2233 	}
2234 
2235 	return false;
2236 }
2237 
2238 /* Start TX aggregation */
2239 
ath_tx_aggr_start(struct ath_softc * sc,struct ieee80211_sta * sta,u16 tid,u16 * ssn)2240 int ath_tx_aggr_start(struct ath_softc *sc, struct ieee80211_sta *sta,
2241 		      u16 tid, u16 *ssn)
2242 {
2243 	struct ath_atx_tid *txtid;
2244 	struct ath_node *an;
2245 
2246 	an = (struct ath_node *)sta->drv_priv;
2247 
2248 	if (sc->sc_flags & SC_OP_TXAGGR) {
2249 		txtid = ATH_AN_2_TID(an, tid);
2250 		txtid->state |= AGGR_ADDBA_PROGRESS;
2251 		ath_tx_pause_tid(sc, txtid);
2252 	}
2253 
2254 	return 0;
2255 }
2256 
2257 /* Stop tx aggregation */
2258 
ath_tx_aggr_stop(struct ath_softc * sc,struct ieee80211_sta * sta,u16 tid)2259 int ath_tx_aggr_stop(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid)
2260 {
2261 	struct ath_node *an = (struct ath_node *)sta->drv_priv;
2262 
2263 	ath_tx_aggr_teardown(sc, an, tid);
2264 	return 0;
2265 }
2266 
2267 /* Resume tx aggregation */
2268 
ath_tx_aggr_resume(struct ath_softc * sc,struct ieee80211_sta * sta,u16 tid)2269 void ath_tx_aggr_resume(struct ath_softc *sc, struct ieee80211_sta *sta, u16 tid)
2270 {
2271 	struct ath_atx_tid *txtid;
2272 	struct ath_node *an;
2273 
2274 	an = (struct ath_node *)sta->drv_priv;
2275 
2276 	if (sc->sc_flags & SC_OP_TXAGGR) {
2277 		txtid = ATH_AN_2_TID(an, tid);
2278 		txtid->baw_size =
2279 			IEEE80211_MIN_AMPDU_BUF << sta->ht_cap.ampdu_factor;
2280 		txtid->state |= AGGR_ADDBA_COMPLETE;
2281 		txtid->state &= ~AGGR_ADDBA_PROGRESS;
2282 		ath_tx_resume_tid(sc, txtid);
2283 	}
2284 }
2285 
2286 /*
2287  * Performs transmit side cleanup when TID changes from aggregated to
2288  * unaggregated.
2289  * - Pause the TID and mark cleanup in progress
2290  * - Discard all retry frames from the s/w queue.
2291  */
2292 
ath_tx_aggr_teardown(struct ath_softc * sc,struct ath_node * an,u8 tid)2293 void ath_tx_aggr_teardown(struct ath_softc *sc, struct ath_node *an, u8 tid)
2294 {
2295 	struct ath_atx_tid *txtid = ATH_AN_2_TID(an, tid);
2296 	struct ath_txq *txq = &sc->tx.txq[txtid->ac->qnum];
2297 	struct ath_buf *bf;
2298 	struct list_head bf_head;
2299 	INIT_LIST_HEAD(&bf_head);
2300 
2301 	if (txtid->state & AGGR_CLEANUP) /* cleanup is in progress */
2302 		return;
2303 
2304 	if (!(txtid->state & AGGR_ADDBA_COMPLETE)) {
2305 		txtid->addba_exchangeattempts = 0;
2306 		return;
2307 	}
2308 
2309 	/* TID must be paused first */
2310 	ath_tx_pause_tid(sc, txtid);
2311 
2312 	/* drop all software retried frames and mark this TID */
2313 	spin_lock_bh(&txq->axq_lock);
2314 	while (!list_empty(&txtid->buf_q)) {
2315 		bf = list_first_entry(&txtid->buf_q, struct ath_buf, list);
2316 		if (!bf_isretried(bf)) {
2317 			/*
2318 			 * NB: it's based on the assumption that
2319 			 * software retried frame will always stay
2320 			 * at the head of software queue.
2321 			 */
2322 			break;
2323 		}
2324 		list_cut_position(&bf_head,
2325 			&txtid->buf_q, &bf->bf_lastfrm->list);
2326 		ath_tx_update_baw(sc, txtid, bf->bf_seqno);
2327 
2328 		/* complete this sub-frame */
2329 		ath_tx_complete_buf(sc, bf, &bf_head, 0, 0);
2330 	}
2331 
2332 	if (txtid->baw_head != txtid->baw_tail) {
2333 		spin_unlock_bh(&txq->axq_lock);
2334 		txtid->state |= AGGR_CLEANUP;
2335 	} else {
2336 		txtid->state &= ~AGGR_ADDBA_COMPLETE;
2337 		txtid->addba_exchangeattempts = 0;
2338 		spin_unlock_bh(&txq->axq_lock);
2339 		ath_tx_flush_tid(sc, txtid);
2340 	}
2341 }
2342 
2343 /*
2344  * Tx scheduling logic
2345  * NB: must be called with txq lock held
2346  */
2347 
ath_txq_schedule(struct ath_softc * sc,struct ath_txq * txq)2348 void ath_txq_schedule(struct ath_softc *sc, struct ath_txq *txq)
2349 {
2350 	struct ath_atx_ac *ac;
2351 	struct ath_atx_tid *tid;
2352 
2353 	/* nothing to schedule */
2354 	if (list_empty(&txq->axq_acq))
2355 		return;
2356 	/*
2357 	 * get the first node/ac pair on the queue
2358 	 */
2359 	ac = list_first_entry(&txq->axq_acq, struct ath_atx_ac, list);
2360 	list_del(&ac->list);
2361 	ac->sched = false;
2362 
2363 	/*
2364 	 * process a single tid per destination
2365 	 */
2366 	do {
2367 		/* nothing to schedule */
2368 		if (list_empty(&ac->tid_q))
2369 			return;
2370 
2371 		tid = list_first_entry(&ac->tid_q, struct ath_atx_tid, list);
2372 		list_del(&tid->list);
2373 		tid->sched = false;
2374 
2375 		if (tid->paused)    /* check next tid to keep h/w busy */
2376 			continue;
2377 
2378 		if ((txq->axq_depth % 2) == 0)
2379 			ath_tx_sched_aggr(sc, txq, tid);
2380 
2381 		/*
2382 		 * add tid to round-robin queue if more frames
2383 		 * are pending for the tid
2384 		 */
2385 		if (!list_empty(&tid->buf_q))
2386 			ath_tx_queue_tid(txq, tid);
2387 
2388 		/* only schedule one TID at a time */
2389 		break;
2390 	} while (!list_empty(&ac->tid_q));
2391 
2392 	/*
2393 	 * schedule AC if more TIDs need processing
2394 	 */
2395 	if (!list_empty(&ac->tid_q)) {
2396 		/*
2397 		 * add dest ac to txq if not already added
2398 		 */
2399 		if (!ac->sched) {
2400 			ac->sched = true;
2401 			list_add_tail(&ac->list, &txq->axq_acq);
2402 		}
2403 	}
2404 }
2405 
2406 /* Initialize per-node transmit state */
2407 
ath_tx_node_init(struct ath_softc * sc,struct ath_node * an)2408 void ath_tx_node_init(struct ath_softc *sc, struct ath_node *an)
2409 {
2410 	struct ath_atx_tid *tid;
2411 	struct ath_atx_ac *ac;
2412 	int tidno, acno;
2413 
2414 	/*
2415 	 * Init per tid tx state
2416 	 */
2417 	for (tidno = 0, tid = &an->tid[tidno];
2418 	     tidno < WME_NUM_TID;
2419 	     tidno++, tid++) {
2420 		tid->an        = an;
2421 		tid->tidno     = tidno;
2422 		tid->seq_start = tid->seq_next = 0;
2423 		tid->baw_size  = WME_MAX_BA;
2424 		tid->baw_head  = tid->baw_tail = 0;
2425 		tid->sched     = false;
2426 		tid->paused = false;
2427 		tid->state &= ~AGGR_CLEANUP;
2428 		INIT_LIST_HEAD(&tid->buf_q);
2429 
2430 		acno = TID_TO_WME_AC(tidno);
2431 		tid->ac = &an->ac[acno];
2432 
2433 		/* ADDBA state */
2434 		tid->state &= ~AGGR_ADDBA_COMPLETE;
2435 		tid->state &= ~AGGR_ADDBA_PROGRESS;
2436 		tid->addba_exchangeattempts = 0;
2437 	}
2438 
2439 	/*
2440 	 * Init per ac tx state
2441 	 */
2442 	for (acno = 0, ac = &an->ac[acno];
2443 	     acno < WME_NUM_AC; acno++, ac++) {
2444 		ac->sched    = false;
2445 		INIT_LIST_HEAD(&ac->tid_q);
2446 
2447 		switch (acno) {
2448 		case WME_AC_BE:
2449 			ac->qnum = ath_tx_get_qnum(sc,
2450 				   ATH9K_TX_QUEUE_DATA, ATH9K_WME_AC_BE);
2451 			break;
2452 		case WME_AC_BK:
2453 			ac->qnum = ath_tx_get_qnum(sc,
2454 				   ATH9K_TX_QUEUE_DATA, ATH9K_WME_AC_BK);
2455 			break;
2456 		case WME_AC_VI:
2457 			ac->qnum = ath_tx_get_qnum(sc,
2458 				   ATH9K_TX_QUEUE_DATA, ATH9K_WME_AC_VI);
2459 			break;
2460 		case WME_AC_VO:
2461 			ac->qnum = ath_tx_get_qnum(sc,
2462 				   ATH9K_TX_QUEUE_DATA, ATH9K_WME_AC_VO);
2463 			break;
2464 		}
2465 	}
2466 }
2467 
2468 /* Cleanupthe pending buffers for the node. */
2469 
ath_tx_node_cleanup(struct ath_softc * sc,struct ath_node * an)2470 void ath_tx_node_cleanup(struct ath_softc *sc, struct ath_node *an)
2471 {
2472 	int i;
2473 	struct ath_atx_ac *ac, *ac_tmp;
2474 	struct ath_atx_tid *tid, *tid_tmp;
2475 	struct ath_txq *txq;
2476 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++) {
2477 		if (ATH_TXQ_SETUP(sc, i)) {
2478 			txq = &sc->tx.txq[i];
2479 
2480 			spin_lock(&txq->axq_lock);
2481 
2482 			list_for_each_entry_safe(ac,
2483 					ac_tmp, &txq->axq_acq, list) {
2484 				tid = list_first_entry(&ac->tid_q,
2485 						struct ath_atx_tid, list);
2486 				if (tid && tid->an != an)
2487 					continue;
2488 				list_del(&ac->list);
2489 				ac->sched = false;
2490 
2491 				list_for_each_entry_safe(tid,
2492 						tid_tmp, &ac->tid_q, list) {
2493 					list_del(&tid->list);
2494 					tid->sched = false;
2495 					ath_tid_drain(sc, txq, tid);
2496 					tid->state &= ~AGGR_ADDBA_COMPLETE;
2497 					tid->addba_exchangeattempts = 0;
2498 					tid->state &= ~AGGR_CLEANUP;
2499 				}
2500 			}
2501 
2502 			spin_unlock(&txq->axq_lock);
2503 		}
2504 	}
2505 }
2506 
ath_tx_cabq(struct ath_softc * sc,struct sk_buff * skb)2507 void ath_tx_cabq(struct ath_softc *sc, struct sk_buff *skb)
2508 {
2509 	int hdrlen, padsize;
2510 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
2511 	struct ath_tx_control txctl;
2512 
2513 	memset(&txctl, 0, sizeof(struct ath_tx_control));
2514 
2515 	/*
2516 	 * As a temporary workaround, assign seq# here; this will likely need
2517 	 * to be cleaned up to work better with Beacon transmission and virtual
2518 	 * BSSes.
2519 	 */
2520 	if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
2521 		struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
2522 		if (info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)
2523 			sc->tx.seq_no += 0x10;
2524 		hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
2525 		hdr->seq_ctrl |= cpu_to_le16(sc->tx.seq_no);
2526 	}
2527 
2528 	/* Add the padding after the header if this is not already done */
2529 	hdrlen = ieee80211_get_hdrlen_from_skb(skb);
2530 	if (hdrlen & 3) {
2531 		padsize = hdrlen % 4;
2532 		if (skb_headroom(skb) < padsize) {
2533 			DPRINTF(sc, ATH_DBG_XMIT, "TX CABQ padding failed\n");
2534 			dev_kfree_skb_any(skb);
2535 			return;
2536 		}
2537 		skb_push(skb, padsize);
2538 		memmove(skb->data, skb->data + padsize, hdrlen);
2539 	}
2540 
2541 	txctl.txq = sc->beacon.cabq;
2542 
2543 	DPRINTF(sc, ATH_DBG_XMIT, "transmitting CABQ packet, skb: %p\n", skb);
2544 
2545 	if (ath_tx_start(sc, skb, &txctl) != 0) {
2546 		DPRINTF(sc, ATH_DBG_XMIT, "CABQ TX failed\n");
2547 		goto exit;
2548 	}
2549 
2550 	return;
2551 exit:
2552 	dev_kfree_skb_any(skb);
2553 }
2554