xref: /linux/drivers/net/wireless/ath/carl9170/tx.c (revision f2ee442115c9b6219083c019939a9cc0c9abb2f8)
1 /*
2  * Atheros CARL9170 driver
3  *
4  * 802.11 xmit & status routines
5  *
6  * Copyright 2008, Johannes Berg <johannes@sipsolutions.net>
7  * Copyright 2009, 2010, Christian Lamparter <chunkeey@googlemail.com>
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; see the file COPYING.  If not, see
21  * http://www.gnu.org/licenses/.
22  *
23  * This file incorporates work covered by the following copyright and
24  * permission notice:
25  *    Copyright (c) 2007-2008 Atheros Communications, Inc.
26  *
27  *    Permission to use, copy, modify, and/or distribute this software for any
28  *    purpose with or without fee is hereby granted, provided that the above
29  *    copyright notice and this permission notice appear in all copies.
30  *
31  *    THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
32  *    WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
33  *    MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
34  *    ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
35  *    WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
36  *    ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
37  *    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
38  */
39 
40 #include <linux/init.h>
41 #include <linux/slab.h>
42 #include <linux/module.h>
43 #include <linux/etherdevice.h>
44 #include <net/mac80211.h>
45 #include "carl9170.h"
46 #include "hw.h"
47 #include "cmd.h"
48 
49 static inline unsigned int __carl9170_get_queue(struct ar9170 *ar,
50 						unsigned int queue)
51 {
52 	if (unlikely(modparam_noht)) {
53 		return queue;
54 	} else {
55 		/*
56 		 * This is just another workaround, until
57 		 * someone figures out how to get QoS and
58 		 * AMPDU to play nicely together.
59 		 */
60 
61 		return 2;		/* AC_BE */
62 	}
63 }
64 
65 static inline unsigned int carl9170_get_queue(struct ar9170 *ar,
66 					      struct sk_buff *skb)
67 {
68 	return __carl9170_get_queue(ar, skb_get_queue_mapping(skb));
69 }
70 
71 static bool is_mem_full(struct ar9170 *ar)
72 {
73 	return (DIV_ROUND_UP(IEEE80211_MAX_FRAME_LEN, ar->fw.mem_block_size) >
74 		atomic_read(&ar->mem_free_blocks));
75 }
76 
77 static void carl9170_tx_accounting(struct ar9170 *ar, struct sk_buff *skb)
78 {
79 	int queue, i;
80 	bool mem_full;
81 
82 	atomic_inc(&ar->tx_total_queued);
83 
84 	queue = skb_get_queue_mapping(skb);
85 	spin_lock_bh(&ar->tx_stats_lock);
86 
87 	/*
88 	 * The driver has to accept the frame, regardless if the queue is
89 	 * full to the brim, or not. We have to do the queuing internally,
90 	 * since mac80211 assumes that a driver which can operate with
91 	 * aggregated frames does not reject frames for this reason.
92 	 */
93 	ar->tx_stats[queue].len++;
94 	ar->tx_stats[queue].count++;
95 
96 	mem_full = is_mem_full(ar);
97 	for (i = 0; i < ar->hw->queues; i++) {
98 		if (mem_full || ar->tx_stats[i].len >= ar->tx_stats[i].limit) {
99 			ieee80211_stop_queue(ar->hw, i);
100 			ar->queue_stop_timeout[i] = jiffies;
101 		}
102 	}
103 
104 	spin_unlock_bh(&ar->tx_stats_lock);
105 }
106 
107 /* needs rcu_read_lock */
108 static struct ieee80211_sta *__carl9170_get_tx_sta(struct ar9170 *ar,
109 						   struct sk_buff *skb)
110 {
111 	struct _carl9170_tx_superframe *super = (void *) skb->data;
112 	struct ieee80211_hdr *hdr = (void *) super->frame_data;
113 	struct ieee80211_vif *vif;
114 	unsigned int vif_id;
115 
116 	vif_id = (super->s.misc & CARL9170_TX_SUPER_MISC_VIF_ID) >>
117 		 CARL9170_TX_SUPER_MISC_VIF_ID_S;
118 
119 	if (WARN_ON_ONCE(vif_id >= AR9170_MAX_VIRTUAL_MAC))
120 		return NULL;
121 
122 	vif = rcu_dereference(ar->vif_priv[vif_id].vif);
123 	if (unlikely(!vif))
124 		return NULL;
125 
126 	/*
127 	 * Normally we should use wrappers like ieee80211_get_DA to get
128 	 * the correct peer ieee80211_sta.
129 	 *
130 	 * But there is a problem with indirect traffic (broadcasts, or
131 	 * data which is designated for other stations) in station mode.
132 	 * The frame will be directed to the AP for distribution and not
133 	 * to the actual destination.
134 	 */
135 
136 	return ieee80211_find_sta(vif, hdr->addr1);
137 }
138 
139 static void carl9170_tx_ps_unblock(struct ar9170 *ar, struct sk_buff *skb)
140 {
141 	struct ieee80211_sta *sta;
142 	struct carl9170_sta_info *sta_info;
143 
144 	rcu_read_lock();
145 	sta = __carl9170_get_tx_sta(ar, skb);
146 	if (unlikely(!sta))
147 		goto out_rcu;
148 
149 	sta_info = (struct carl9170_sta_info *) sta->drv_priv;
150 	if (atomic_dec_return(&sta_info->pending_frames) == 0)
151 		ieee80211_sta_block_awake(ar->hw, sta, false);
152 
153 out_rcu:
154 	rcu_read_unlock();
155 }
156 
157 static void carl9170_tx_accounting_free(struct ar9170 *ar, struct sk_buff *skb)
158 {
159 	int queue;
160 
161 	queue = skb_get_queue_mapping(skb);
162 
163 	spin_lock_bh(&ar->tx_stats_lock);
164 
165 	ar->tx_stats[queue].len--;
166 
167 	if (!is_mem_full(ar)) {
168 		unsigned int i;
169 		for (i = 0; i < ar->hw->queues; i++) {
170 			if (ar->tx_stats[i].len >= CARL9170_NUM_TX_LIMIT_SOFT)
171 				continue;
172 
173 			if (ieee80211_queue_stopped(ar->hw, i)) {
174 				unsigned long tmp;
175 
176 				tmp = jiffies - ar->queue_stop_timeout[i];
177 				if (tmp > ar->max_queue_stop_timeout[i])
178 					ar->max_queue_stop_timeout[i] = tmp;
179 			}
180 
181 			ieee80211_wake_queue(ar->hw, i);
182 		}
183 	}
184 
185 	spin_unlock_bh(&ar->tx_stats_lock);
186 
187 	if (atomic_dec_and_test(&ar->tx_total_queued))
188 		complete(&ar->tx_flush);
189 }
190 
191 static int carl9170_alloc_dev_space(struct ar9170 *ar, struct sk_buff *skb)
192 {
193 	struct _carl9170_tx_superframe *super = (void *) skb->data;
194 	unsigned int chunks;
195 	int cookie = -1;
196 
197 	atomic_inc(&ar->mem_allocs);
198 
199 	chunks = DIV_ROUND_UP(skb->len, ar->fw.mem_block_size);
200 	if (unlikely(atomic_sub_return(chunks, &ar->mem_free_blocks) < 0)) {
201 		atomic_add(chunks, &ar->mem_free_blocks);
202 		return -ENOSPC;
203 	}
204 
205 	spin_lock_bh(&ar->mem_lock);
206 	cookie = bitmap_find_free_region(ar->mem_bitmap, ar->fw.mem_blocks, 0);
207 	spin_unlock_bh(&ar->mem_lock);
208 
209 	if (unlikely(cookie < 0)) {
210 		atomic_add(chunks, &ar->mem_free_blocks);
211 		return -ENOSPC;
212 	}
213 
214 	super = (void *) skb->data;
215 
216 	/*
217 	 * Cookie #0 serves two special purposes:
218 	 *  1. The firmware might use it generate BlockACK frames
219 	 *     in responds of an incoming BlockAckReqs.
220 	 *
221 	 *  2. Prevent double-free bugs.
222 	 */
223 	super->s.cookie = (u8) cookie + 1;
224 	return 0;
225 }
226 
227 static void carl9170_release_dev_space(struct ar9170 *ar, struct sk_buff *skb)
228 {
229 	struct _carl9170_tx_superframe *super = (void *) skb->data;
230 	int cookie;
231 
232 	/* make a local copy of the cookie */
233 	cookie = super->s.cookie;
234 	/* invalidate cookie */
235 	super->s.cookie = 0;
236 
237 	/*
238 	 * Do a out-of-bounds check on the cookie:
239 	 *
240 	 *  * cookie "0" is reserved and won't be assigned to any
241 	 *    out-going frame. Internally however, it is used to
242 	 *    mark no longer/un-accounted frames and serves as a
243 	 *    cheap way of preventing frames from being freed
244 	 *    twice by _accident_. NB: There is a tiny race...
245 	 *
246 	 *  * obviously, cookie number is limited by the amount
247 	 *    of available memory blocks, so the number can
248 	 *    never execeed the mem_blocks count.
249 	 */
250 	if (unlikely(WARN_ON_ONCE(cookie == 0) ||
251 	    WARN_ON_ONCE(cookie > ar->fw.mem_blocks)))
252 		return;
253 
254 	atomic_add(DIV_ROUND_UP(skb->len, ar->fw.mem_block_size),
255 		   &ar->mem_free_blocks);
256 
257 	spin_lock_bh(&ar->mem_lock);
258 	bitmap_release_region(ar->mem_bitmap, cookie - 1, 0);
259 	spin_unlock_bh(&ar->mem_lock);
260 }
261 
262 /* Called from any context */
263 static void carl9170_tx_release(struct kref *ref)
264 {
265 	struct ar9170 *ar;
266 	struct carl9170_tx_info *arinfo;
267 	struct ieee80211_tx_info *txinfo;
268 	struct sk_buff *skb;
269 
270 	arinfo = container_of(ref, struct carl9170_tx_info, ref);
271 	txinfo = container_of((void *) arinfo, struct ieee80211_tx_info,
272 			      rate_driver_data);
273 	skb = container_of((void *) txinfo, struct sk_buff, cb);
274 
275 	ar = arinfo->ar;
276 	if (WARN_ON_ONCE(!ar))
277 		return;
278 
279 	BUILD_BUG_ON(
280 	    offsetof(struct ieee80211_tx_info, status.ampdu_ack_len) != 23);
281 
282 	memset(&txinfo->status.ampdu_ack_len, 0,
283 	       sizeof(struct ieee80211_tx_info) -
284 	       offsetof(struct ieee80211_tx_info, status.ampdu_ack_len));
285 
286 	if (atomic_read(&ar->tx_total_queued))
287 		ar->tx_schedule = true;
288 
289 	if (txinfo->flags & IEEE80211_TX_CTL_AMPDU) {
290 		if (!atomic_read(&ar->tx_ampdu_upload))
291 			ar->tx_ampdu_schedule = true;
292 
293 		if (txinfo->flags & IEEE80211_TX_STAT_AMPDU) {
294 			struct _carl9170_tx_superframe *super;
295 
296 			super = (void *)skb->data;
297 			txinfo->status.ampdu_len = super->s.rix;
298 			txinfo->status.ampdu_ack_len = super->s.cnt;
299 		} else if ((txinfo->flags & IEEE80211_TX_STAT_ACK) &&
300 			   !(txinfo->flags & IEEE80211_TX_CTL_REQ_TX_STATUS)) {
301 			/*
302 			 * drop redundant tx_status reports:
303 			 *
304 			 * 1. ampdu_ack_len of the final tx_status does
305 			 *    include the feedback of this particular frame.
306 			 *
307 			 * 2. tx_status_irqsafe only queues up to 128
308 			 *    tx feedback reports and discards the rest.
309 			 *
310 			 * 3. minstrel_ht is picky, it only accepts
311 			 *    reports of frames with the TX_STATUS_AMPDU flag.
312 			 *
313 			 * 4. mac80211 is not particularly interested in
314 			 *    feedback either [CTL_REQ_TX_STATUS not set]
315 			 */
316 
317 			dev_kfree_skb_any(skb);
318 			return;
319 		} else {
320 			/*
321 			 * Either the frame transmission has failed or
322 			 * mac80211 requested tx status.
323 			 */
324 		}
325 	}
326 
327 	skb_pull(skb, sizeof(struct _carl9170_tx_superframe));
328 	ieee80211_tx_status_irqsafe(ar->hw, skb);
329 }
330 
331 void carl9170_tx_get_skb(struct sk_buff *skb)
332 {
333 	struct carl9170_tx_info *arinfo = (void *)
334 		(IEEE80211_SKB_CB(skb))->rate_driver_data;
335 	kref_get(&arinfo->ref);
336 }
337 
338 int carl9170_tx_put_skb(struct sk_buff *skb)
339 {
340 	struct carl9170_tx_info *arinfo = (void *)
341 		(IEEE80211_SKB_CB(skb))->rate_driver_data;
342 
343 	return kref_put(&arinfo->ref, carl9170_tx_release);
344 }
345 
346 /* Caller must hold the tid_info->lock & rcu_read_lock */
347 static void carl9170_tx_shift_bm(struct ar9170 *ar,
348 	struct carl9170_sta_tid *tid_info, u16 seq)
349 {
350 	u16 off;
351 
352 	off = SEQ_DIFF(seq, tid_info->bsn);
353 
354 	if (WARN_ON_ONCE(off >= CARL9170_BAW_BITS))
355 		return;
356 
357 	/*
358 	 * Sanity check. For each MPDU we set the bit in bitmap and
359 	 * clear it once we received the tx_status.
360 	 * But if the bit is already cleared then we've been bitten
361 	 * by a bug.
362 	 */
363 	WARN_ON_ONCE(!test_and_clear_bit(off, tid_info->bitmap));
364 
365 	off = SEQ_DIFF(tid_info->snx, tid_info->bsn);
366 	if (WARN_ON_ONCE(off >= CARL9170_BAW_BITS))
367 		return;
368 
369 	if (!bitmap_empty(tid_info->bitmap, off))
370 		off = find_first_bit(tid_info->bitmap, off);
371 
372 	tid_info->bsn += off;
373 	tid_info->bsn &= 0x0fff;
374 
375 	bitmap_shift_right(tid_info->bitmap, tid_info->bitmap,
376 			   off, CARL9170_BAW_BITS);
377 }
378 
379 static void carl9170_tx_status_process_ampdu(struct ar9170 *ar,
380 	struct sk_buff *skb, struct ieee80211_tx_info *txinfo)
381 {
382 	struct _carl9170_tx_superframe *super = (void *) skb->data;
383 	struct ieee80211_hdr *hdr = (void *) super->frame_data;
384 	struct ieee80211_sta *sta;
385 	struct carl9170_sta_info *sta_info;
386 	struct carl9170_sta_tid *tid_info;
387 	u8 tid;
388 
389 	if (!(txinfo->flags & IEEE80211_TX_CTL_AMPDU) ||
390 	    txinfo->flags & IEEE80211_TX_CTL_INJECTED ||
391 	   (!(super->f.mac_control & cpu_to_le16(AR9170_TX_MAC_AGGR))))
392 		return;
393 
394 	rcu_read_lock();
395 	sta = __carl9170_get_tx_sta(ar, skb);
396 	if (unlikely(!sta))
397 		goto out_rcu;
398 
399 	tid = get_tid_h(hdr);
400 
401 	sta_info = (void *) sta->drv_priv;
402 	tid_info = rcu_dereference(sta_info->agg[tid]);
403 	if (!tid_info)
404 		goto out_rcu;
405 
406 	spin_lock_bh(&tid_info->lock);
407 	if (likely(tid_info->state >= CARL9170_TID_STATE_IDLE))
408 		carl9170_tx_shift_bm(ar, tid_info, get_seq_h(hdr));
409 
410 	if (sta_info->stats[tid].clear) {
411 		sta_info->stats[tid].clear = false;
412 		sta_info->stats[tid].req = false;
413 		sta_info->stats[tid].ampdu_len = 0;
414 		sta_info->stats[tid].ampdu_ack_len = 0;
415 	}
416 
417 	sta_info->stats[tid].ampdu_len++;
418 	if (txinfo->status.rates[0].count == 1)
419 		sta_info->stats[tid].ampdu_ack_len++;
420 
421 	if (!(txinfo->flags & IEEE80211_TX_STAT_ACK))
422 		sta_info->stats[tid].req = true;
423 
424 	if (super->f.mac_control & cpu_to_le16(AR9170_TX_MAC_IMM_BA)) {
425 		super->s.rix = sta_info->stats[tid].ampdu_len;
426 		super->s.cnt = sta_info->stats[tid].ampdu_ack_len;
427 		txinfo->flags |= IEEE80211_TX_STAT_AMPDU;
428 		if (sta_info->stats[tid].req)
429 			txinfo->flags |= IEEE80211_TX_STAT_AMPDU_NO_BACK;
430 
431 		sta_info->stats[tid].clear = true;
432 	}
433 	spin_unlock_bh(&tid_info->lock);
434 
435 out_rcu:
436 	rcu_read_unlock();
437 }
438 
439 void carl9170_tx_status(struct ar9170 *ar, struct sk_buff *skb,
440 			const bool success)
441 {
442 	struct ieee80211_tx_info *txinfo;
443 
444 	carl9170_tx_accounting_free(ar, skb);
445 
446 	txinfo = IEEE80211_SKB_CB(skb);
447 
448 	if (success)
449 		txinfo->flags |= IEEE80211_TX_STAT_ACK;
450 	else
451 		ar->tx_ack_failures++;
452 
453 	if (txinfo->flags & IEEE80211_TX_CTL_AMPDU)
454 		carl9170_tx_status_process_ampdu(ar, skb, txinfo);
455 
456 	carl9170_tx_ps_unblock(ar, skb);
457 	carl9170_tx_put_skb(skb);
458 }
459 
460 /* This function may be called form any context */
461 void carl9170_tx_callback(struct ar9170 *ar, struct sk_buff *skb)
462 {
463 	struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
464 
465 	atomic_dec(&ar->tx_total_pending);
466 
467 	if (txinfo->flags & IEEE80211_TX_CTL_AMPDU)
468 		atomic_dec(&ar->tx_ampdu_upload);
469 
470 	if (carl9170_tx_put_skb(skb))
471 		tasklet_hi_schedule(&ar->usb_tasklet);
472 }
473 
474 static struct sk_buff *carl9170_get_queued_skb(struct ar9170 *ar, u8 cookie,
475 					       struct sk_buff_head *queue)
476 {
477 	struct sk_buff *skb;
478 
479 	spin_lock_bh(&queue->lock);
480 	skb_queue_walk(queue, skb) {
481 		struct _carl9170_tx_superframe *txc = (void *) skb->data;
482 
483 		if (txc->s.cookie != cookie)
484 			continue;
485 
486 		__skb_unlink(skb, queue);
487 		spin_unlock_bh(&queue->lock);
488 
489 		carl9170_release_dev_space(ar, skb);
490 		return skb;
491 	}
492 	spin_unlock_bh(&queue->lock);
493 
494 	return NULL;
495 }
496 
497 static void carl9170_tx_fill_rateinfo(struct ar9170 *ar, unsigned int rix,
498 	unsigned int tries, struct ieee80211_tx_info *txinfo)
499 {
500 	unsigned int i;
501 
502 	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
503 		if (txinfo->status.rates[i].idx < 0)
504 			break;
505 
506 		if (i == rix) {
507 			txinfo->status.rates[i].count = tries;
508 			i++;
509 			break;
510 		}
511 	}
512 
513 	for (; i < IEEE80211_TX_MAX_RATES; i++) {
514 		txinfo->status.rates[i].idx = -1;
515 		txinfo->status.rates[i].count = 0;
516 	}
517 }
518 
519 static void carl9170_check_queue_stop_timeout(struct ar9170 *ar)
520 {
521 	int i;
522 	struct sk_buff *skb;
523 	struct ieee80211_tx_info *txinfo;
524 	struct carl9170_tx_info *arinfo;
525 	bool restart = false;
526 
527 	for (i = 0; i < ar->hw->queues; i++) {
528 		spin_lock_bh(&ar->tx_status[i].lock);
529 
530 		skb = skb_peek(&ar->tx_status[i]);
531 
532 		if (!skb)
533 			goto next;
534 
535 		txinfo = IEEE80211_SKB_CB(skb);
536 		arinfo = (void *) txinfo->rate_driver_data;
537 
538 		if (time_is_before_jiffies(arinfo->timeout +
539 		    msecs_to_jiffies(CARL9170_QUEUE_STUCK_TIMEOUT)) == true)
540 			restart = true;
541 
542 next:
543 		spin_unlock_bh(&ar->tx_status[i].lock);
544 	}
545 
546 	if (restart) {
547 		/*
548 		 * At least one queue has been stuck for long enough.
549 		 * Give the device a kick and hope it gets back to
550 		 * work.
551 		 *
552 		 * possible reasons may include:
553 		 *  - frames got lost/corrupted (bad connection to the device)
554 		 *  - stalled rx processing/usb controller hiccups
555 		 *  - firmware errors/bugs
556 		 *  - every bug you can think of.
557 		 *  - all bugs you can't...
558 		 *  - ...
559 		 */
560 		carl9170_restart(ar, CARL9170_RR_STUCK_TX);
561 	}
562 }
563 
564 static void carl9170_tx_ampdu_timeout(struct ar9170 *ar)
565 {
566 	struct carl9170_sta_tid *iter;
567 	struct sk_buff *skb;
568 	struct ieee80211_tx_info *txinfo;
569 	struct carl9170_tx_info *arinfo;
570 	struct ieee80211_sta *sta;
571 
572 	rcu_read_lock();
573 	list_for_each_entry_rcu(iter, &ar->tx_ampdu_list, list) {
574 		if (iter->state < CARL9170_TID_STATE_IDLE)
575 			continue;
576 
577 		spin_lock_bh(&iter->lock);
578 		skb = skb_peek(&iter->queue);
579 		if (!skb)
580 			goto unlock;
581 
582 		txinfo = IEEE80211_SKB_CB(skb);
583 		arinfo = (void *)txinfo->rate_driver_data;
584 		if (time_is_after_jiffies(arinfo->timeout +
585 		    msecs_to_jiffies(CARL9170_QUEUE_TIMEOUT)))
586 			goto unlock;
587 
588 		sta = __carl9170_get_tx_sta(ar, skb);
589 		if (WARN_ON(!sta))
590 			goto unlock;
591 
592 		ieee80211_stop_tx_ba_session(sta, iter->tid);
593 unlock:
594 		spin_unlock_bh(&iter->lock);
595 
596 	}
597 	rcu_read_unlock();
598 }
599 
600 void carl9170_tx_janitor(struct work_struct *work)
601 {
602 	struct ar9170 *ar = container_of(work, struct ar9170,
603 					 tx_janitor.work);
604 	if (!IS_STARTED(ar))
605 		return;
606 
607 	ar->tx_janitor_last_run = jiffies;
608 
609 	carl9170_check_queue_stop_timeout(ar);
610 	carl9170_tx_ampdu_timeout(ar);
611 
612 	if (!atomic_read(&ar->tx_total_queued))
613 		return;
614 
615 	ieee80211_queue_delayed_work(ar->hw, &ar->tx_janitor,
616 		msecs_to_jiffies(CARL9170_TX_TIMEOUT));
617 }
618 
619 static void __carl9170_tx_process_status(struct ar9170 *ar,
620 	const uint8_t cookie, const uint8_t info)
621 {
622 	struct sk_buff *skb;
623 	struct ieee80211_tx_info *txinfo;
624 	unsigned int r, t, q;
625 	bool success = true;
626 
627 	q = ar9170_qmap[info & CARL9170_TX_STATUS_QUEUE];
628 
629 	skb = carl9170_get_queued_skb(ar, cookie, &ar->tx_status[q]);
630 	if (!skb) {
631 		/*
632 		 * We have lost the race to another thread.
633 		 */
634 
635 		return ;
636 	}
637 
638 	txinfo = IEEE80211_SKB_CB(skb);
639 
640 	if (!(info & CARL9170_TX_STATUS_SUCCESS))
641 		success = false;
642 
643 	r = (info & CARL9170_TX_STATUS_RIX) >> CARL9170_TX_STATUS_RIX_S;
644 	t = (info & CARL9170_TX_STATUS_TRIES) >> CARL9170_TX_STATUS_TRIES_S;
645 
646 	carl9170_tx_fill_rateinfo(ar, r, t, txinfo);
647 	carl9170_tx_status(ar, skb, success);
648 }
649 
650 void carl9170_tx_process_status(struct ar9170 *ar,
651 				const struct carl9170_rsp *cmd)
652 {
653 	unsigned int i;
654 
655 	for (i = 0;  i < cmd->hdr.ext; i++) {
656 		if (WARN_ON(i > ((cmd->hdr.len / 2) + 1))) {
657 			print_hex_dump_bytes("UU:", DUMP_PREFIX_NONE,
658 					     (void *) cmd, cmd->hdr.len + 4);
659 			break;
660 		}
661 
662 		__carl9170_tx_process_status(ar, cmd->_tx_status[i].cookie,
663 					     cmd->_tx_status[i].info);
664 	}
665 }
666 
667 static void carl9170_tx_rate_tpc_chains(struct ar9170 *ar,
668 	struct ieee80211_tx_info *info,	struct ieee80211_tx_rate *txrate,
669 	unsigned int *phyrate, unsigned int *tpc, unsigned int *chains)
670 {
671 	struct ieee80211_rate *rate = NULL;
672 	u8 *txpower;
673 	unsigned int idx;
674 
675 	idx = txrate->idx;
676 	*tpc = 0;
677 	*phyrate = 0;
678 
679 	if (txrate->flags & IEEE80211_TX_RC_MCS) {
680 		if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
681 			/* +1 dBm for HT40 */
682 			*tpc += 2;
683 
684 			if (info->band == IEEE80211_BAND_2GHZ)
685 				txpower = ar->power_2G_ht40;
686 			else
687 				txpower = ar->power_5G_ht40;
688 		} else {
689 			if (info->band == IEEE80211_BAND_2GHZ)
690 				txpower = ar->power_2G_ht20;
691 			else
692 				txpower = ar->power_5G_ht20;
693 		}
694 
695 		*phyrate = txrate->idx;
696 		*tpc += txpower[idx & 7];
697 	} else {
698 		if (info->band == IEEE80211_BAND_2GHZ) {
699 			if (idx < 4)
700 				txpower = ar->power_2G_cck;
701 			else
702 				txpower = ar->power_2G_ofdm;
703 		} else {
704 			txpower = ar->power_5G_leg;
705 			idx += 4;
706 		}
707 
708 		rate = &__carl9170_ratetable[idx];
709 		*tpc += txpower[(rate->hw_value & 0x30) >> 4];
710 		*phyrate = rate->hw_value & 0xf;
711 	}
712 
713 	if (ar->eeprom.tx_mask == 1) {
714 		*chains = AR9170_TX_PHY_TXCHAIN_1;
715 	} else {
716 		if (!(txrate->flags & IEEE80211_TX_RC_MCS) &&
717 		    rate && rate->bitrate >= 360)
718 			*chains = AR9170_TX_PHY_TXCHAIN_1;
719 		else
720 			*chains = AR9170_TX_PHY_TXCHAIN_2;
721 	}
722 }
723 
724 static __le32 carl9170_tx_physet(struct ar9170 *ar,
725 	struct ieee80211_tx_info *info, struct ieee80211_tx_rate *txrate)
726 {
727 	unsigned int power = 0, chains = 0, phyrate = 0;
728 	__le32 tmp;
729 
730 	tmp = cpu_to_le32(0);
731 
732 	if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
733 		tmp |= cpu_to_le32(AR9170_TX_PHY_BW_40MHZ <<
734 			AR9170_TX_PHY_BW_S);
735 	/* this works because 40 MHz is 2 and dup is 3 */
736 	if (txrate->flags & IEEE80211_TX_RC_DUP_DATA)
737 		tmp |= cpu_to_le32(AR9170_TX_PHY_BW_40MHZ_DUP <<
738 			AR9170_TX_PHY_BW_S);
739 
740 	if (txrate->flags & IEEE80211_TX_RC_SHORT_GI)
741 		tmp |= cpu_to_le32(AR9170_TX_PHY_SHORT_GI);
742 
743 	if (txrate->flags & IEEE80211_TX_RC_MCS) {
744 		SET_VAL(AR9170_TX_PHY_MCS, phyrate, txrate->idx);
745 
746 		/* heavy clip control */
747 		tmp |= cpu_to_le32((txrate->idx & 0x7) <<
748 			AR9170_TX_PHY_TX_HEAVY_CLIP_S);
749 
750 		tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_HT);
751 
752 		/*
753 		 * green field preamble does not work.
754 		 *
755 		 * if (txrate->flags & IEEE80211_TX_RC_GREEN_FIELD)
756 		 * tmp |= cpu_to_le32(AR9170_TX_PHY_GREENFIELD);
757 		 */
758 	} else {
759 		if (info->band == IEEE80211_BAND_2GHZ) {
760 			if (txrate->idx <= AR9170_TX_PHY_RATE_CCK_11M)
761 				tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_CCK);
762 			else
763 				tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_OFDM);
764 		} else {
765 			tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_OFDM);
766 		}
767 
768 		/*
769 		 * short preamble seems to be broken too.
770 		 *
771 		 * if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
772 		 *	tmp |= cpu_to_le32(AR9170_TX_PHY_SHORT_PREAMBLE);
773 		 */
774 	}
775 	carl9170_tx_rate_tpc_chains(ar, info, txrate,
776 				    &phyrate, &power, &chains);
777 
778 	tmp |= cpu_to_le32(SET_CONSTVAL(AR9170_TX_PHY_MCS, phyrate));
779 	tmp |= cpu_to_le32(SET_CONSTVAL(AR9170_TX_PHY_TX_PWR, power));
780 	tmp |= cpu_to_le32(SET_CONSTVAL(AR9170_TX_PHY_TXCHAIN, chains));
781 	return tmp;
782 }
783 
784 static bool carl9170_tx_rts_check(struct ar9170 *ar,
785 				  struct ieee80211_tx_rate *rate,
786 				  bool ampdu, bool multi)
787 {
788 	switch (ar->erp_mode) {
789 	case CARL9170_ERP_AUTO:
790 		if (ampdu)
791 			break;
792 
793 	case CARL9170_ERP_MAC80211:
794 		if (!(rate->flags & IEEE80211_TX_RC_USE_RTS_CTS))
795 			break;
796 
797 	case CARL9170_ERP_RTS:
798 		if (likely(!multi))
799 			return true;
800 
801 	default:
802 		break;
803 	}
804 
805 	return false;
806 }
807 
808 static bool carl9170_tx_cts_check(struct ar9170 *ar,
809 				  struct ieee80211_tx_rate *rate)
810 {
811 	switch (ar->erp_mode) {
812 	case CARL9170_ERP_AUTO:
813 	case CARL9170_ERP_MAC80211:
814 		if (!(rate->flags & IEEE80211_TX_RC_USE_CTS_PROTECT))
815 			break;
816 
817 	case CARL9170_ERP_CTS:
818 		return true;
819 
820 	default:
821 		break;
822 	}
823 
824 	return false;
825 }
826 
827 static int carl9170_tx_prepare(struct ar9170 *ar, struct sk_buff *skb)
828 {
829 	struct ieee80211_hdr *hdr;
830 	struct _carl9170_tx_superframe *txc;
831 	struct carl9170_vif_info *cvif;
832 	struct ieee80211_tx_info *info;
833 	struct ieee80211_tx_rate *txrate;
834 	struct ieee80211_sta *sta;
835 	struct carl9170_tx_info *arinfo;
836 	unsigned int hw_queue;
837 	int i;
838 	__le16 mac_tmp;
839 	u16 len;
840 	bool ampdu, no_ack;
841 
842 	BUILD_BUG_ON(sizeof(*arinfo) > sizeof(info->rate_driver_data));
843 	BUILD_BUG_ON(sizeof(struct _carl9170_tx_superdesc) !=
844 		     CARL9170_TX_SUPERDESC_LEN);
845 
846 	BUILD_BUG_ON(sizeof(struct _ar9170_tx_hwdesc) !=
847 		     AR9170_TX_HWDESC_LEN);
848 
849 	BUILD_BUG_ON(IEEE80211_TX_MAX_RATES < CARL9170_TX_MAX_RATES);
850 
851 	BUILD_BUG_ON(AR9170_MAX_VIRTUAL_MAC >
852 		((CARL9170_TX_SUPER_MISC_VIF_ID >>
853 		 CARL9170_TX_SUPER_MISC_VIF_ID_S) + 1));
854 
855 	hw_queue = ar9170_qmap[carl9170_get_queue(ar, skb)];
856 
857 	hdr = (void *)skb->data;
858 	info = IEEE80211_SKB_CB(skb);
859 	len = skb->len;
860 
861 	/*
862 	 * Note: If the frame was sent through a monitor interface,
863 	 * the ieee80211_vif pointer can be NULL.
864 	 */
865 	if (likely(info->control.vif))
866 		cvif = (void *) info->control.vif->drv_priv;
867 	else
868 		cvif = NULL;
869 
870 	sta = info->control.sta;
871 
872 	txc = (void *)skb_push(skb, sizeof(*txc));
873 	memset(txc, 0, sizeof(*txc));
874 
875 	SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, txc->s.misc, hw_queue);
876 
877 	if (likely(cvif))
878 		SET_VAL(CARL9170_TX_SUPER_MISC_VIF_ID, txc->s.misc, cvif->id);
879 
880 	if (unlikely(info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM))
881 		txc->s.misc |= CARL9170_TX_SUPER_MISC_CAB;
882 
883 	if (unlikely(info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ))
884 		txc->s.misc |= CARL9170_TX_SUPER_MISC_ASSIGN_SEQ;
885 
886 	if (unlikely(ieee80211_is_probe_resp(hdr->frame_control)))
887 		txc->s.misc |= CARL9170_TX_SUPER_MISC_FILL_IN_TSF;
888 
889 	mac_tmp = cpu_to_le16(AR9170_TX_MAC_HW_DURATION |
890 			      AR9170_TX_MAC_BACKOFF);
891 	mac_tmp |= cpu_to_le16((hw_queue << AR9170_TX_MAC_QOS_S) &
892 			       AR9170_TX_MAC_QOS);
893 
894 	no_ack = !!(info->flags & IEEE80211_TX_CTL_NO_ACK);
895 	if (unlikely(no_ack))
896 		mac_tmp |= cpu_to_le16(AR9170_TX_MAC_NO_ACK);
897 
898 	if (info->control.hw_key) {
899 		len += info->control.hw_key->icv_len;
900 
901 		switch (info->control.hw_key->cipher) {
902 		case WLAN_CIPHER_SUITE_WEP40:
903 		case WLAN_CIPHER_SUITE_WEP104:
904 		case WLAN_CIPHER_SUITE_TKIP:
905 			mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_RC4);
906 			break;
907 		case WLAN_CIPHER_SUITE_CCMP:
908 			mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_AES);
909 			break;
910 		default:
911 			WARN_ON(1);
912 			goto err_out;
913 		}
914 	}
915 
916 	ampdu = !!(info->flags & IEEE80211_TX_CTL_AMPDU);
917 	if (ampdu) {
918 		unsigned int density, factor;
919 
920 		if (unlikely(!sta || !cvif))
921 			goto err_out;
922 
923 		factor = min_t(unsigned int, 1u, sta->ht_cap.ampdu_factor);
924 		density = sta->ht_cap.ampdu_density;
925 
926 		if (density) {
927 			/*
928 			 * Watch out!
929 			 *
930 			 * Otus uses slightly different density values than
931 			 * those from the 802.11n spec.
932 			 */
933 
934 			density = max_t(unsigned int, density + 1, 7u);
935 		}
936 
937 		SET_VAL(CARL9170_TX_SUPER_AMPDU_DENSITY,
938 			txc->s.ampdu_settings, density);
939 
940 		SET_VAL(CARL9170_TX_SUPER_AMPDU_FACTOR,
941 			txc->s.ampdu_settings, factor);
942 
943 		for (i = 0; i < CARL9170_TX_MAX_RATES; i++) {
944 			txrate = &info->control.rates[i];
945 			if (txrate->idx >= 0) {
946 				txc->s.ri[i] =
947 					CARL9170_TX_SUPER_RI_AMPDU;
948 
949 				if (WARN_ON(!(txrate->flags &
950 					      IEEE80211_TX_RC_MCS))) {
951 					/*
952 					 * Not sure if it's even possible
953 					 * to aggregate non-ht rates with
954 					 * this HW.
955 					 */
956 					goto err_out;
957 				}
958 				continue;
959 			}
960 
961 			txrate->idx = 0;
962 			txrate->count = ar->hw->max_rate_tries;
963 		}
964 
965 		mac_tmp |= cpu_to_le16(AR9170_TX_MAC_AGGR);
966 	}
967 
968 	/*
969 	 * NOTE: For the first rate, the ERP & AMPDU flags are directly
970 	 * taken from mac_control. For all fallback rate, the firmware
971 	 * updates the mac_control flags from the rate info field.
972 	 */
973 	for (i = 1; i < CARL9170_TX_MAX_RATES; i++) {
974 		txrate = &info->control.rates[i];
975 		if (txrate->idx < 0)
976 			break;
977 
978 		SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[i],
979 			txrate->count);
980 
981 		if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
982 			txc->s.ri[i] |= (AR9170_TX_MAC_PROT_RTS <<
983 				CARL9170_TX_SUPER_RI_ERP_PROT_S);
984 		else if (carl9170_tx_cts_check(ar, txrate))
985 			txc->s.ri[i] |= (AR9170_TX_MAC_PROT_CTS <<
986 				CARL9170_TX_SUPER_RI_ERP_PROT_S);
987 
988 		txc->s.rr[i - 1] = carl9170_tx_physet(ar, info, txrate);
989 	}
990 
991 	txrate = &info->control.rates[0];
992 	SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[0], txrate->count);
993 
994 	if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
995 		mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_RTS);
996 	else if (carl9170_tx_cts_check(ar, txrate))
997 		mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_CTS);
998 
999 	txc->s.len = cpu_to_le16(skb->len);
1000 	txc->f.length = cpu_to_le16(len + FCS_LEN);
1001 	txc->f.mac_control = mac_tmp;
1002 	txc->f.phy_control = carl9170_tx_physet(ar, info, txrate);
1003 
1004 	arinfo = (void *)info->rate_driver_data;
1005 	arinfo->timeout = jiffies;
1006 	arinfo->ar = ar;
1007 	kref_init(&arinfo->ref);
1008 	return 0;
1009 
1010 err_out:
1011 	skb_pull(skb, sizeof(*txc));
1012 	return -EINVAL;
1013 }
1014 
1015 static void carl9170_set_immba(struct ar9170 *ar, struct sk_buff *skb)
1016 {
1017 	struct _carl9170_tx_superframe *super;
1018 
1019 	super = (void *) skb->data;
1020 	super->f.mac_control |= cpu_to_le16(AR9170_TX_MAC_IMM_BA);
1021 }
1022 
1023 static void carl9170_set_ampdu_params(struct ar9170 *ar, struct sk_buff *skb)
1024 {
1025 	struct _carl9170_tx_superframe *super;
1026 	int tmp;
1027 
1028 	super = (void *) skb->data;
1029 
1030 	tmp = (super->s.ampdu_settings & CARL9170_TX_SUPER_AMPDU_DENSITY) <<
1031 		CARL9170_TX_SUPER_AMPDU_DENSITY_S;
1032 
1033 	/*
1034 	 * If you haven't noticed carl9170_tx_prepare has already filled
1035 	 * in all ampdu spacing & factor parameters.
1036 	 * Now it's the time to check whenever the settings have to be
1037 	 * updated by the firmware, or if everything is still the same.
1038 	 *
1039 	 * There's no sane way to handle different density values with
1040 	 * this hardware, so we may as well just do the compare in the
1041 	 * driver.
1042 	 */
1043 
1044 	if (tmp != ar->current_density) {
1045 		ar->current_density = tmp;
1046 		super->s.ampdu_settings |=
1047 			CARL9170_TX_SUPER_AMPDU_COMMIT_DENSITY;
1048 	}
1049 
1050 	tmp = (super->s.ampdu_settings & CARL9170_TX_SUPER_AMPDU_FACTOR) <<
1051 		CARL9170_TX_SUPER_AMPDU_FACTOR_S;
1052 
1053 	if (tmp != ar->current_factor) {
1054 		ar->current_factor = tmp;
1055 		super->s.ampdu_settings |=
1056 			CARL9170_TX_SUPER_AMPDU_COMMIT_FACTOR;
1057 	}
1058 }
1059 
1060 static bool carl9170_tx_rate_check(struct ar9170 *ar, struct sk_buff *_dest,
1061 				   struct sk_buff *_src)
1062 {
1063 	struct _carl9170_tx_superframe *dest, *src;
1064 
1065 	dest = (void *) _dest->data;
1066 	src = (void *) _src->data;
1067 
1068 	/*
1069 	 * The mac80211 rate control algorithm expects that all MPDUs in
1070 	 * an AMPDU share the same tx vectors.
1071 	 * This is not really obvious right now, because the hardware
1072 	 * does the AMPDU setup according to its own rulebook.
1073 	 * Our nicely assembled, strictly monotonic increasing mpdu
1074 	 * chains will be broken up, mashed back together...
1075 	 */
1076 
1077 	return (dest->f.phy_control == src->f.phy_control);
1078 }
1079 
1080 static void carl9170_tx_ampdu(struct ar9170 *ar)
1081 {
1082 	struct sk_buff_head agg;
1083 	struct carl9170_sta_tid *tid_info;
1084 	struct sk_buff *skb, *first;
1085 	unsigned int i = 0, done_ampdus = 0;
1086 	u16 seq, queue, tmpssn;
1087 
1088 	atomic_inc(&ar->tx_ampdu_scheduler);
1089 	ar->tx_ampdu_schedule = false;
1090 
1091 	if (atomic_read(&ar->tx_ampdu_upload))
1092 		return;
1093 
1094 	if (!ar->tx_ampdu_list_len)
1095 		return;
1096 
1097 	__skb_queue_head_init(&agg);
1098 
1099 	rcu_read_lock();
1100 	tid_info = rcu_dereference(ar->tx_ampdu_iter);
1101 	if (WARN_ON_ONCE(!tid_info)) {
1102 		rcu_read_unlock();
1103 		return;
1104 	}
1105 
1106 retry:
1107 	list_for_each_entry_continue_rcu(tid_info, &ar->tx_ampdu_list, list) {
1108 		i++;
1109 
1110 		if (tid_info->state < CARL9170_TID_STATE_PROGRESS)
1111 			continue;
1112 
1113 		queue = TID_TO_WME_AC(tid_info->tid);
1114 
1115 		spin_lock_bh(&tid_info->lock);
1116 		if (tid_info->state != CARL9170_TID_STATE_XMIT)
1117 			goto processed;
1118 
1119 		tid_info->counter++;
1120 		first = skb_peek(&tid_info->queue);
1121 		tmpssn = carl9170_get_seq(first);
1122 		seq = tid_info->snx;
1123 
1124 		if (unlikely(tmpssn != seq)) {
1125 			tid_info->state = CARL9170_TID_STATE_IDLE;
1126 
1127 			goto processed;
1128 		}
1129 
1130 		while ((skb = skb_peek(&tid_info->queue))) {
1131 			/* strict 0, 1, ..., n - 1, n frame sequence order */
1132 			if (unlikely(carl9170_get_seq(skb) != seq))
1133 				break;
1134 
1135 			/* don't upload more than AMPDU FACTOR allows. */
1136 			if (unlikely(SEQ_DIFF(tid_info->snx, tid_info->bsn) >=
1137 			    (tid_info->max - 1)))
1138 				break;
1139 
1140 			if (!carl9170_tx_rate_check(ar, skb, first))
1141 				break;
1142 
1143 			atomic_inc(&ar->tx_ampdu_upload);
1144 			tid_info->snx = seq = SEQ_NEXT(seq);
1145 			__skb_unlink(skb, &tid_info->queue);
1146 
1147 			__skb_queue_tail(&agg, skb);
1148 
1149 			if (skb_queue_len(&agg) >= CARL9170_NUM_TX_AGG_MAX)
1150 				break;
1151 		}
1152 
1153 		if (skb_queue_empty(&tid_info->queue) ||
1154 		    carl9170_get_seq(skb_peek(&tid_info->queue)) !=
1155 		    tid_info->snx) {
1156 			/*
1157 			 * stop TID, if A-MPDU frames are still missing,
1158 			 * or whenever the queue is empty.
1159 			 */
1160 
1161 			tid_info->state = CARL9170_TID_STATE_IDLE;
1162 		}
1163 		done_ampdus++;
1164 
1165 processed:
1166 		spin_unlock_bh(&tid_info->lock);
1167 
1168 		if (skb_queue_empty(&agg))
1169 			continue;
1170 
1171 		/* apply ampdu spacing & factor settings */
1172 		carl9170_set_ampdu_params(ar, skb_peek(&agg));
1173 
1174 		/* set aggregation push bit */
1175 		carl9170_set_immba(ar, skb_peek_tail(&agg));
1176 
1177 		spin_lock_bh(&ar->tx_pending[queue].lock);
1178 		skb_queue_splice_tail_init(&agg, &ar->tx_pending[queue]);
1179 		spin_unlock_bh(&ar->tx_pending[queue].lock);
1180 		ar->tx_schedule = true;
1181 	}
1182 	if ((done_ampdus++ == 0) && (i++ == 0))
1183 		goto retry;
1184 
1185 	rcu_assign_pointer(ar->tx_ampdu_iter, tid_info);
1186 	rcu_read_unlock();
1187 }
1188 
1189 static struct sk_buff *carl9170_tx_pick_skb(struct ar9170 *ar,
1190 					    struct sk_buff_head *queue)
1191 {
1192 	struct sk_buff *skb;
1193 	struct ieee80211_tx_info *info;
1194 	struct carl9170_tx_info *arinfo;
1195 
1196 	BUILD_BUG_ON(sizeof(*arinfo) > sizeof(info->rate_driver_data));
1197 
1198 	spin_lock_bh(&queue->lock);
1199 	skb = skb_peek(queue);
1200 	if (unlikely(!skb))
1201 		goto err_unlock;
1202 
1203 	if (carl9170_alloc_dev_space(ar, skb))
1204 		goto err_unlock;
1205 
1206 	__skb_unlink(skb, queue);
1207 	spin_unlock_bh(&queue->lock);
1208 
1209 	info = IEEE80211_SKB_CB(skb);
1210 	arinfo = (void *) info->rate_driver_data;
1211 
1212 	arinfo->timeout = jiffies;
1213 	return skb;
1214 
1215 err_unlock:
1216 	spin_unlock_bh(&queue->lock);
1217 	return NULL;
1218 }
1219 
1220 void carl9170_tx_drop(struct ar9170 *ar, struct sk_buff *skb)
1221 {
1222 	struct _carl9170_tx_superframe *super;
1223 	uint8_t q = 0;
1224 
1225 	ar->tx_dropped++;
1226 
1227 	super = (void *)skb->data;
1228 	SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, q,
1229 		ar9170_qmap[carl9170_get_queue(ar, skb)]);
1230 	__carl9170_tx_process_status(ar, super->s.cookie, q);
1231 }
1232 
1233 static bool carl9170_tx_ps_drop(struct ar9170 *ar, struct sk_buff *skb)
1234 {
1235 	struct ieee80211_sta *sta;
1236 	struct carl9170_sta_info *sta_info;
1237 
1238 	rcu_read_lock();
1239 	sta = __carl9170_get_tx_sta(ar, skb);
1240 	if (!sta)
1241 		goto out_rcu;
1242 
1243 	sta_info = (void *) sta->drv_priv;
1244 	if (unlikely(sta_info->sleeping)) {
1245 		struct ieee80211_tx_info *tx_info;
1246 
1247 		rcu_read_unlock();
1248 
1249 		tx_info = IEEE80211_SKB_CB(skb);
1250 		if (tx_info->flags & IEEE80211_TX_CTL_AMPDU)
1251 			atomic_dec(&ar->tx_ampdu_upload);
1252 
1253 		tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
1254 		carl9170_tx_status(ar, skb, false);
1255 		return true;
1256 	}
1257 
1258 out_rcu:
1259 	rcu_read_unlock();
1260 	return false;
1261 }
1262 
1263 static void carl9170_tx(struct ar9170 *ar)
1264 {
1265 	struct sk_buff *skb;
1266 	unsigned int i, q;
1267 	bool schedule_garbagecollector = false;
1268 
1269 	ar->tx_schedule = false;
1270 
1271 	if (unlikely(!IS_STARTED(ar)))
1272 		return;
1273 
1274 	carl9170_usb_handle_tx_err(ar);
1275 
1276 	for (i = 0; i < ar->hw->queues; i++) {
1277 		while (!skb_queue_empty(&ar->tx_pending[i])) {
1278 			skb = carl9170_tx_pick_skb(ar, &ar->tx_pending[i]);
1279 			if (unlikely(!skb))
1280 				break;
1281 
1282 			if (unlikely(carl9170_tx_ps_drop(ar, skb)))
1283 				continue;
1284 
1285 			atomic_inc(&ar->tx_total_pending);
1286 
1287 			q = __carl9170_get_queue(ar, i);
1288 			/*
1289 			 * NB: tx_status[i] vs. tx_status[q],
1290 			 * TODO: Move into pick_skb or alloc_dev_space.
1291 			 */
1292 			skb_queue_tail(&ar->tx_status[q], skb);
1293 
1294 			/*
1295 			 * increase ref count to "2".
1296 			 * Ref counting is the easiest way to solve the
1297 			 * race between the urb's completion routine:
1298 			 *	carl9170_tx_callback
1299 			 * and wlan tx status functions:
1300 			 *	carl9170_tx_status/janitor.
1301 			 */
1302 			carl9170_tx_get_skb(skb);
1303 
1304 			carl9170_usb_tx(ar, skb);
1305 			schedule_garbagecollector = true;
1306 		}
1307 	}
1308 
1309 	if (!schedule_garbagecollector)
1310 		return;
1311 
1312 	ieee80211_queue_delayed_work(ar->hw, &ar->tx_janitor,
1313 		msecs_to_jiffies(CARL9170_TX_TIMEOUT));
1314 }
1315 
1316 static bool carl9170_tx_ampdu_queue(struct ar9170 *ar,
1317 	struct ieee80211_sta *sta, struct sk_buff *skb)
1318 {
1319 	struct _carl9170_tx_superframe *super = (void *) skb->data;
1320 	struct carl9170_sta_info *sta_info;
1321 	struct carl9170_sta_tid *agg;
1322 	struct sk_buff *iter;
1323 	u16 tid, seq, qseq, off;
1324 	bool run = false;
1325 
1326 	tid = carl9170_get_tid(skb);
1327 	seq = carl9170_get_seq(skb);
1328 	sta_info = (void *) sta->drv_priv;
1329 
1330 	rcu_read_lock();
1331 	agg = rcu_dereference(sta_info->agg[tid]);
1332 
1333 	if (!agg)
1334 		goto err_unlock_rcu;
1335 
1336 	spin_lock_bh(&agg->lock);
1337 	if (unlikely(agg->state < CARL9170_TID_STATE_IDLE))
1338 		goto err_unlock;
1339 
1340 	/* check if sequence is within the BA window */
1341 	if (unlikely(!BAW_WITHIN(agg->bsn, CARL9170_BAW_BITS, seq)))
1342 		goto err_unlock;
1343 
1344 	if (WARN_ON_ONCE(!BAW_WITHIN(agg->snx, CARL9170_BAW_BITS, seq)))
1345 		goto err_unlock;
1346 
1347 	off = SEQ_DIFF(seq, agg->bsn);
1348 	if (WARN_ON_ONCE(test_and_set_bit(off, agg->bitmap)))
1349 		goto err_unlock;
1350 
1351 	if (likely(BAW_WITHIN(agg->hsn, CARL9170_BAW_BITS, seq))) {
1352 		__skb_queue_tail(&agg->queue, skb);
1353 		agg->hsn = seq;
1354 		goto queued;
1355 	}
1356 
1357 	skb_queue_reverse_walk(&agg->queue, iter) {
1358 		qseq = carl9170_get_seq(iter);
1359 
1360 		if (BAW_WITHIN(qseq, CARL9170_BAW_BITS, seq)) {
1361 			__skb_queue_after(&agg->queue, iter, skb);
1362 			goto queued;
1363 		}
1364 	}
1365 
1366 	__skb_queue_head(&agg->queue, skb);
1367 queued:
1368 
1369 	if (unlikely(agg->state != CARL9170_TID_STATE_XMIT)) {
1370 		if (agg->snx == carl9170_get_seq(skb_peek(&agg->queue))) {
1371 			agg->state = CARL9170_TID_STATE_XMIT;
1372 			run = true;
1373 		}
1374 	}
1375 
1376 	spin_unlock_bh(&agg->lock);
1377 	rcu_read_unlock();
1378 
1379 	return run;
1380 
1381 err_unlock:
1382 	spin_unlock_bh(&agg->lock);
1383 
1384 err_unlock_rcu:
1385 	rcu_read_unlock();
1386 	super->f.mac_control &= ~cpu_to_le16(AR9170_TX_MAC_AGGR);
1387 	carl9170_tx_status(ar, skb, false);
1388 	ar->tx_dropped++;
1389 	return false;
1390 }
1391 
1392 void carl9170_op_tx(struct ieee80211_hw *hw, struct sk_buff *skb)
1393 {
1394 	struct ar9170 *ar = hw->priv;
1395 	struct ieee80211_tx_info *info;
1396 	struct ieee80211_sta *sta;
1397 	bool run;
1398 
1399 	if (unlikely(!IS_STARTED(ar)))
1400 		goto err_free;
1401 
1402 	info = IEEE80211_SKB_CB(skb);
1403 	sta = info->control.sta;
1404 
1405 	if (unlikely(carl9170_tx_prepare(ar, skb)))
1406 		goto err_free;
1407 
1408 	carl9170_tx_accounting(ar, skb);
1409 	/*
1410 	 * from now on, one has to use carl9170_tx_status to free
1411 	 * all ressouces which are associated with the frame.
1412 	 */
1413 
1414 	if (sta) {
1415 		struct carl9170_sta_info *stai = (void *) sta->drv_priv;
1416 		atomic_inc(&stai->pending_frames);
1417 	}
1418 
1419 	if (info->flags & IEEE80211_TX_CTL_AMPDU) {
1420 		run = carl9170_tx_ampdu_queue(ar, sta, skb);
1421 		if (run)
1422 			carl9170_tx_ampdu(ar);
1423 
1424 	} else {
1425 		unsigned int queue = skb_get_queue_mapping(skb);
1426 
1427 		skb_queue_tail(&ar->tx_pending[queue], skb);
1428 	}
1429 
1430 	carl9170_tx(ar);
1431 	return;
1432 
1433 err_free:
1434 	ar->tx_dropped++;
1435 	dev_kfree_skb_any(skb);
1436 }
1437 
1438 void carl9170_tx_scheduler(struct ar9170 *ar)
1439 {
1440 
1441 	if (ar->tx_ampdu_schedule)
1442 		carl9170_tx_ampdu(ar);
1443 
1444 	if (ar->tx_schedule)
1445 		carl9170_tx(ar);
1446 }
1447 
1448 int carl9170_update_beacon(struct ar9170 *ar, const bool submit)
1449 {
1450 	struct sk_buff *skb = NULL;
1451 	struct carl9170_vif_info *cvif;
1452 	struct ieee80211_tx_info *txinfo;
1453 	struct ieee80211_tx_rate *rate;
1454 	__le32 *data, *old = NULL;
1455 	unsigned int plcp, power, chains;
1456 	u32 word, ht1, off, addr, len;
1457 	int i = 0, err = 0;
1458 
1459 	rcu_read_lock();
1460 	cvif = rcu_dereference(ar->beacon_iter);
1461 retry:
1462 	if (ar->vifs == 0 || !cvif)
1463 		goto out_unlock;
1464 
1465 	list_for_each_entry_continue_rcu(cvif, &ar->vif_list, list) {
1466 		if (cvif->active && cvif->enable_beacon)
1467 			goto found;
1468 	}
1469 
1470 	if (!ar->beacon_enabled || i++)
1471 		goto out_unlock;
1472 
1473 	goto retry;
1474 
1475 found:
1476 	rcu_assign_pointer(ar->beacon_iter, cvif);
1477 
1478 	skb = ieee80211_beacon_get_tim(ar->hw, carl9170_get_vif(cvif),
1479 		NULL, NULL);
1480 
1481 	if (!skb) {
1482 		err = -ENOMEM;
1483 		goto err_free;
1484 	}
1485 
1486 	txinfo = IEEE80211_SKB_CB(skb);
1487 	spin_lock_bh(&ar->beacon_lock);
1488 	data = (__le32 *)skb->data;
1489 	if (cvif->beacon)
1490 		old = (__le32 *)cvif->beacon->data;
1491 
1492 	off = cvif->id * AR9170_MAC_BCN_LENGTH_MAX;
1493 	addr = ar->fw.beacon_addr + off;
1494 	len = roundup(skb->len + FCS_LEN, 4);
1495 
1496 	if ((off + len) > ar->fw.beacon_max_len) {
1497 		if (net_ratelimit()) {
1498 			wiphy_err(ar->hw->wiphy, "beacon does not "
1499 				  "fit into device memory!\n");
1500 		}
1501 		err = -EINVAL;
1502 		goto err_unlock;
1503 	}
1504 
1505 	if (len > AR9170_MAC_BCN_LENGTH_MAX) {
1506 		if (net_ratelimit()) {
1507 			wiphy_err(ar->hw->wiphy, "no support for beacons "
1508 				"bigger than %d (yours:%d).\n",
1509 				 AR9170_MAC_BCN_LENGTH_MAX, len);
1510 		}
1511 
1512 		err = -EMSGSIZE;
1513 		goto err_unlock;
1514 	}
1515 
1516 	ht1 = AR9170_MAC_BCN_HT1_TX_ANT0;
1517 	rate = &txinfo->control.rates[0];
1518 	carl9170_tx_rate_tpc_chains(ar, txinfo, rate, &plcp, &power, &chains);
1519 	if (!(txinfo->control.rates[0].flags & IEEE80211_TX_RC_MCS)) {
1520 		if (plcp <= AR9170_TX_PHY_RATE_CCK_11M)
1521 			plcp |= ((skb->len + FCS_LEN) << (3 + 16)) + 0x0400;
1522 		else
1523 			plcp |= ((skb->len + FCS_LEN) << 16) + 0x0010;
1524 	} else {
1525 		ht1 |= AR9170_MAC_BCN_HT1_HT_EN;
1526 		if (rate->flags & IEEE80211_TX_RC_SHORT_GI)
1527 			plcp |= AR9170_MAC_BCN_HT2_SGI;
1528 
1529 		if (rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
1530 			ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_SHARED;
1531 			plcp |= AR9170_MAC_BCN_HT2_BW40;
1532 		}
1533 		if (rate->flags & IEEE80211_TX_RC_DUP_DATA) {
1534 			ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_DUP;
1535 			plcp |= AR9170_MAC_BCN_HT2_BW40;
1536 		}
1537 
1538 		SET_VAL(AR9170_MAC_BCN_HT2_LEN, plcp, skb->len + FCS_LEN);
1539 	}
1540 
1541 	SET_VAL(AR9170_MAC_BCN_HT1_PWR_CTRL, ht1, 7);
1542 	SET_VAL(AR9170_MAC_BCN_HT1_TPC, ht1, power);
1543 	SET_VAL(AR9170_MAC_BCN_HT1_CHAIN_MASK, ht1, chains);
1544 	if (chains == AR9170_TX_PHY_TXCHAIN_2)
1545 		ht1 |= AR9170_MAC_BCN_HT1_TX_ANT1;
1546 
1547 	carl9170_async_regwrite_begin(ar);
1548 	carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT1, ht1);
1549 	if (!(txinfo->control.rates[0].flags & IEEE80211_TX_RC_MCS))
1550 		carl9170_async_regwrite(AR9170_MAC_REG_BCN_PLCP, plcp);
1551 	else
1552 		carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT2, plcp);
1553 
1554 	for (i = 0; i < DIV_ROUND_UP(skb->len, 4); i++) {
1555 		/*
1556 		 * XXX: This accesses beyond skb data for up
1557 		 *	to the last 3 bytes!!
1558 		 */
1559 
1560 		if (old && (data[i] == old[i]))
1561 			continue;
1562 
1563 		word = le32_to_cpu(data[i]);
1564 		carl9170_async_regwrite(addr + 4 * i, word);
1565 	}
1566 	carl9170_async_regwrite_finish();
1567 
1568 	dev_kfree_skb_any(cvif->beacon);
1569 	cvif->beacon = NULL;
1570 
1571 	err = carl9170_async_regwrite_result();
1572 	if (!err)
1573 		cvif->beacon = skb;
1574 	spin_unlock_bh(&ar->beacon_lock);
1575 	if (err)
1576 		goto err_free;
1577 
1578 	if (submit) {
1579 		err = carl9170_bcn_ctrl(ar, cvif->id,
1580 					CARL9170_BCN_CTRL_CAB_TRIGGER,
1581 					addr, skb->len + FCS_LEN);
1582 
1583 		if (err)
1584 			goto err_free;
1585 	}
1586 out_unlock:
1587 	rcu_read_unlock();
1588 	return 0;
1589 
1590 err_unlock:
1591 	spin_unlock_bh(&ar->beacon_lock);
1592 
1593 err_free:
1594 	rcu_read_unlock();
1595 	dev_kfree_skb_any(skb);
1596 	return err;
1597 }
1598