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/slab.h>
41#include <linux/module.h>
42#include <linux/etherdevice.h>
43#include <net/mac80211.h>
44#include "carl9170.h"
45#include "hw.h"
46#include "cmd.h"
47
48static inline unsigned int __carl9170_get_queue(struct ar9170 *ar,
49						unsigned int queue)
50{
51	if (unlikely(modparam_noht)) {
52		return queue;
53	} else {
54		/*
55		 * This is just another workaround, until
56		 * someone figures out how to get QoS and
57		 * AMPDU to play nicely together.
58		 */
59
60		return 2;		/* AC_BE */
61	}
62}
63
64static inline unsigned int carl9170_get_queue(struct ar9170 *ar,
65					      struct sk_buff *skb)
66{
67	return __carl9170_get_queue(ar, skb_get_queue_mapping(skb));
68}
69
70static bool is_mem_full(struct ar9170 *ar)
71{
72	return (DIV_ROUND_UP(IEEE80211_MAX_FRAME_LEN, ar->fw.mem_block_size) >
73		atomic_read(&ar->mem_free_blocks));
74}
75
76static void carl9170_tx_accounting(struct ar9170 *ar, struct sk_buff *skb)
77{
78	int queue, i;
79	bool mem_full;
80
81	atomic_inc(&ar->tx_total_queued);
82
83	queue = skb_get_queue_mapping(skb);
84	spin_lock_bh(&ar->tx_stats_lock);
85
86	/*
87	 * The driver has to accept the frame, regardless if the queue is
88	 * full to the brim, or not. We have to do the queuing internally,
89	 * since mac80211 assumes that a driver which can operate with
90	 * aggregated frames does not reject frames for this reason.
91	 */
92	ar->tx_stats[queue].len++;
93	ar->tx_stats[queue].count++;
94
95	mem_full = is_mem_full(ar);
96	for (i = 0; i < ar->hw->queues; i++) {
97		if (mem_full || ar->tx_stats[i].len >= ar->tx_stats[i].limit) {
98			ieee80211_stop_queue(ar->hw, i);
99			ar->queue_stop_timeout[i] = jiffies;
100		}
101	}
102
103	spin_unlock_bh(&ar->tx_stats_lock);
104}
105
106/* needs rcu_read_lock */
107static struct ieee80211_sta *__carl9170_get_tx_sta(struct ar9170 *ar,
108						   struct sk_buff *skb)
109{
110	struct _carl9170_tx_superframe *super = (void *) skb->data;
111	struct ieee80211_hdr *hdr = (void *) super->frame_data;
112	struct ieee80211_vif *vif;
113	unsigned int vif_id;
114
115	vif_id = (super->s.misc & CARL9170_TX_SUPER_MISC_VIF_ID) >>
116		 CARL9170_TX_SUPER_MISC_VIF_ID_S;
117
118	if (WARN_ON_ONCE(vif_id >= AR9170_MAX_VIRTUAL_MAC))
119		return NULL;
120
121	vif = rcu_dereference(ar->vif_priv[vif_id].vif);
122	if (unlikely(!vif))
123		return NULL;
124
125	/*
126	 * Normally we should use wrappers like ieee80211_get_DA to get
127	 * the correct peer ieee80211_sta.
128	 *
129	 * But there is a problem with indirect traffic (broadcasts, or
130	 * data which is designated for other stations) in station mode.
131	 * The frame will be directed to the AP for distribution and not
132	 * to the actual destination.
133	 */
134
135	return ieee80211_find_sta(vif, hdr->addr1);
136}
137
138static void carl9170_tx_ps_unblock(struct ar9170 *ar, struct sk_buff *skb)
139{
140	struct ieee80211_sta *sta;
141	struct carl9170_sta_info *sta_info;
142
143	rcu_read_lock();
144	sta = __carl9170_get_tx_sta(ar, skb);
145	if (unlikely(!sta))
146		goto out_rcu;
147
148	sta_info = (struct carl9170_sta_info *) sta->drv_priv;
149	if (atomic_dec_return(&sta_info->pending_frames) == 0)
150		ieee80211_sta_block_awake(ar->hw, sta, false);
151
152out_rcu:
153	rcu_read_unlock();
154}
155
156static void carl9170_tx_accounting_free(struct ar9170 *ar, struct sk_buff *skb)
157{
158	int queue;
159
160	queue = skb_get_queue_mapping(skb);
161
162	spin_lock_bh(&ar->tx_stats_lock);
163
164	ar->tx_stats[queue].len--;
165
166	if (!is_mem_full(ar)) {
167		unsigned int i;
168		for (i = 0; i < ar->hw->queues; i++) {
169			if (ar->tx_stats[i].len >= CARL9170_NUM_TX_LIMIT_SOFT)
170				continue;
171
172			if (ieee80211_queue_stopped(ar->hw, i)) {
173				unsigned long tmp;
174
175				tmp = jiffies - ar->queue_stop_timeout[i];
176				if (tmp > ar->max_queue_stop_timeout[i])
177					ar->max_queue_stop_timeout[i] = tmp;
178			}
179
180			ieee80211_wake_queue(ar->hw, i);
181		}
182	}
183
184	spin_unlock_bh(&ar->tx_stats_lock);
185
186	if (atomic_dec_and_test(&ar->tx_total_queued))
187		complete(&ar->tx_flush);
188}
189
190static int carl9170_alloc_dev_space(struct ar9170 *ar, struct sk_buff *skb)
191{
192	struct _carl9170_tx_superframe *super = (void *) skb->data;
193	unsigned int chunks;
194	int cookie = -1;
195
196	atomic_inc(&ar->mem_allocs);
197
198	chunks = DIV_ROUND_UP(skb->len, ar->fw.mem_block_size);
199	if (unlikely(atomic_sub_return(chunks, &ar->mem_free_blocks) < 0)) {
200		atomic_add(chunks, &ar->mem_free_blocks);
201		return -ENOSPC;
202	}
203
204	spin_lock_bh(&ar->mem_lock);
205	cookie = bitmap_find_free_region(ar->mem_bitmap, ar->fw.mem_blocks, 0);
206	spin_unlock_bh(&ar->mem_lock);
207
208	if (unlikely(cookie < 0)) {
209		atomic_add(chunks, &ar->mem_free_blocks);
210		return -ENOSPC;
211	}
212
213	super = (void *) skb->data;
214
215	/*
216	 * Cookie #0 serves two special purposes:
217	 *  1. The firmware might use it generate BlockACK frames
218	 *     in responds of an incoming BlockAckReqs.
219	 *
220	 *  2. Prevent double-free bugs.
221	 */
222	super->s.cookie = (u8) cookie + 1;
223	return 0;
224}
225
226static void carl9170_release_dev_space(struct ar9170 *ar, struct sk_buff *skb)
227{
228	struct _carl9170_tx_superframe *super = (void *) skb->data;
229	int cookie;
230
231	/* make a local copy of the cookie */
232	cookie = super->s.cookie;
233	/* invalidate cookie */
234	super->s.cookie = 0;
235
236	/*
237	 * Do a out-of-bounds check on the cookie:
238	 *
239	 *  * cookie "0" is reserved and won't be assigned to any
240	 *    out-going frame. Internally however, it is used to
241	 *    mark no longer/un-accounted frames and serves as a
242	 *    cheap way of preventing frames from being freed
243	 *    twice by _accident_. NB: There is a tiny race...
244	 *
245	 *  * obviously, cookie number is limited by the amount
246	 *    of available memory blocks, so the number can
247	 *    never execeed the mem_blocks count.
248	 */
249	if (WARN_ON_ONCE(cookie == 0) ||
250	    WARN_ON_ONCE(cookie > ar->fw.mem_blocks))
251		return;
252
253	atomic_add(DIV_ROUND_UP(skb->len, ar->fw.mem_block_size),
254		   &ar->mem_free_blocks);
255
256	spin_lock_bh(&ar->mem_lock);
257	bitmap_release_region(ar->mem_bitmap, cookie - 1, 0);
258	spin_unlock_bh(&ar->mem_lock);
259}
260
261/* Called from any context */
262static void carl9170_tx_release(struct kref *ref)
263{
264	struct ar9170 *ar;
265	struct carl9170_tx_info *arinfo;
266	struct ieee80211_tx_info *txinfo;
267	struct sk_buff *skb;
268
269	arinfo = container_of(ref, struct carl9170_tx_info, ref);
270	txinfo = container_of((void *) arinfo, struct ieee80211_tx_info,
271			      rate_driver_data);
272	skb = container_of((void *) txinfo, struct sk_buff, cb);
273
274	ar = arinfo->ar;
275	if (WARN_ON_ONCE(!ar))
276		return;
277
278	BUILD_BUG_ON(
279	    offsetof(struct ieee80211_tx_info, status.ack_signal) != 20);
280
281	memset(&txinfo->status.ack_signal, 0,
282	       sizeof(struct ieee80211_tx_info) -
283	       offsetof(struct ieee80211_tx_info, status.ack_signal));
284
285	if (atomic_read(&ar->tx_total_queued))
286		ar->tx_schedule = true;
287
288	if (txinfo->flags & IEEE80211_TX_CTL_AMPDU) {
289		if (!atomic_read(&ar->tx_ampdu_upload))
290			ar->tx_ampdu_schedule = true;
291
292		if (txinfo->flags & IEEE80211_TX_STAT_AMPDU) {
293			struct _carl9170_tx_superframe *super;
294
295			super = (void *)skb->data;
296			txinfo->status.ampdu_len = super->s.rix;
297			txinfo->status.ampdu_ack_len = super->s.cnt;
298		} else if ((txinfo->flags & IEEE80211_TX_STAT_ACK) &&
299			   !(txinfo->flags & IEEE80211_TX_CTL_REQ_TX_STATUS)) {
300			/*
301			 * drop redundant tx_status reports:
302			 *
303			 * 1. ampdu_ack_len of the final tx_status does
304			 *    include the feedback of this particular frame.
305			 *
306			 * 2. tx_status_irqsafe only queues up to 128
307			 *    tx feedback reports and discards the rest.
308			 *
309			 * 3. minstrel_ht is picky, it only accepts
310			 *    reports of frames with the TX_STATUS_AMPDU flag.
311			 *
312			 * 4. mac80211 is not particularly interested in
313			 *    feedback either [CTL_REQ_TX_STATUS not set]
314			 */
315
316			ieee80211_free_txskb(ar->hw, skb);
317			return;
318		} else {
319			/*
320			 * Either the frame transmission has failed or
321			 * mac80211 requested tx status.
322			 */
323		}
324	}
325
326	skb_pull(skb, sizeof(struct _carl9170_tx_superframe));
327	ieee80211_tx_status_irqsafe(ar->hw, skb);
328}
329
330void carl9170_tx_get_skb(struct sk_buff *skb)
331{
332	struct carl9170_tx_info *arinfo = (void *)
333		(IEEE80211_SKB_CB(skb))->rate_driver_data;
334	kref_get(&arinfo->ref);
335}
336
337int carl9170_tx_put_skb(struct sk_buff *skb)
338{
339	struct carl9170_tx_info *arinfo = (void *)
340		(IEEE80211_SKB_CB(skb))->rate_driver_data;
341
342	return kref_put(&arinfo->ref, carl9170_tx_release);
343}
344
345/* Caller must hold the tid_info->lock & rcu_read_lock */
346static void carl9170_tx_shift_bm(struct ar9170 *ar,
347	struct carl9170_sta_tid *tid_info, u16 seq)
348{
349	u16 off;
350
351	off = SEQ_DIFF(seq, tid_info->bsn);
352
353	if (WARN_ON_ONCE(off >= CARL9170_BAW_BITS))
354		return;
355
356	/*
357	 * Sanity check. For each MPDU we set the bit in bitmap and
358	 * clear it once we received the tx_status.
359	 * But if the bit is already cleared then we've been bitten
360	 * by a bug.
361	 */
362	WARN_ON_ONCE(!test_and_clear_bit(off, tid_info->bitmap));
363
364	off = SEQ_DIFF(tid_info->snx, tid_info->bsn);
365	if (WARN_ON_ONCE(off >= CARL9170_BAW_BITS))
366		return;
367
368	if (!bitmap_empty(tid_info->bitmap, off))
369		off = find_first_bit(tid_info->bitmap, off);
370
371	tid_info->bsn += off;
372	tid_info->bsn &= 0x0fff;
373
374	bitmap_shift_right(tid_info->bitmap, tid_info->bitmap,
375			   off, CARL9170_BAW_BITS);
376}
377
378static void carl9170_tx_status_process_ampdu(struct ar9170 *ar,
379	struct sk_buff *skb, struct ieee80211_tx_info *txinfo)
380{
381	struct _carl9170_tx_superframe *super = (void *) skb->data;
382	struct ieee80211_hdr *hdr = (void *) super->frame_data;
383	struct ieee80211_sta *sta;
384	struct carl9170_sta_info *sta_info;
385	struct carl9170_sta_tid *tid_info;
386	u8 tid;
387
388	if (!(txinfo->flags & IEEE80211_TX_CTL_AMPDU) ||
389	    txinfo->flags & IEEE80211_TX_CTL_INJECTED)
390		return;
391
392	rcu_read_lock();
393	sta = __carl9170_get_tx_sta(ar, skb);
394	if (unlikely(!sta))
395		goto out_rcu;
396
397	tid = get_tid_h(hdr);
398
399	sta_info = (void *) sta->drv_priv;
400	tid_info = rcu_dereference(sta_info->agg[tid]);
401	if (!tid_info)
402		goto out_rcu;
403
404	spin_lock_bh(&tid_info->lock);
405	if (likely(tid_info->state >= CARL9170_TID_STATE_IDLE))
406		carl9170_tx_shift_bm(ar, tid_info, get_seq_h(hdr));
407
408	if (sta_info->stats[tid].clear) {
409		sta_info->stats[tid].clear = false;
410		sta_info->stats[tid].req = false;
411		sta_info->stats[tid].ampdu_len = 0;
412		sta_info->stats[tid].ampdu_ack_len = 0;
413	}
414
415	sta_info->stats[tid].ampdu_len++;
416	if (txinfo->status.rates[0].count == 1)
417		sta_info->stats[tid].ampdu_ack_len++;
418
419	if (!(txinfo->flags & IEEE80211_TX_STAT_ACK))
420		sta_info->stats[tid].req = true;
421
422	if (super->f.mac_control & cpu_to_le16(AR9170_TX_MAC_IMM_BA)) {
423		super->s.rix = sta_info->stats[tid].ampdu_len;
424		super->s.cnt = sta_info->stats[tid].ampdu_ack_len;
425		txinfo->flags |= IEEE80211_TX_STAT_AMPDU;
426		if (sta_info->stats[tid].req)
427			txinfo->flags |= IEEE80211_TX_STAT_AMPDU_NO_BACK;
428
429		sta_info->stats[tid].clear = true;
430	}
431	spin_unlock_bh(&tid_info->lock);
432
433out_rcu:
434	rcu_read_unlock();
435}
436
437static void carl9170_tx_bar_status(struct ar9170 *ar, struct sk_buff *skb,
438	struct ieee80211_tx_info *tx_info)
439{
440	struct _carl9170_tx_superframe *super = (void *) skb->data;
441	struct ieee80211_bar *bar = (void *) super->frame_data;
442
443	/*
444	 * Unlike all other frames, the status report for BARs does
445	 * not directly come from the hardware as it is incapable of
446	 * matching a BA to a previously send BAR.
447	 * Instead the RX-path will scan for incoming BAs and set the
448	 * IEEE80211_TX_STAT_ACK if it sees one that was likely
449	 * caused by a BAR from us.
450	 */
451
452	if (unlikely(ieee80211_is_back_req(bar->frame_control)) &&
453	   !(tx_info->flags & IEEE80211_TX_STAT_ACK)) {
454		struct carl9170_bar_list_entry *entry;
455		int queue = skb_get_queue_mapping(skb);
456
457		rcu_read_lock();
458		list_for_each_entry_rcu(entry, &ar->bar_list[queue], list) {
459			if (entry->skb == skb) {
460				spin_lock_bh(&ar->bar_list_lock[queue]);
461				list_del_rcu(&entry->list);
462				spin_unlock_bh(&ar->bar_list_lock[queue]);
463				kfree_rcu(entry, head);
464				goto out;
465			}
466		}
467
468		WARN(1, "bar not found in %d - ra:%pM ta:%pM c:%x ssn:%x\n",
469		       queue, bar->ra, bar->ta, bar->control,
470			bar->start_seq_num);
471out:
472		rcu_read_unlock();
473	}
474}
475
476void carl9170_tx_status(struct ar9170 *ar, struct sk_buff *skb,
477			const bool success)
478{
479	struct ieee80211_tx_info *txinfo;
480
481	carl9170_tx_accounting_free(ar, skb);
482
483	txinfo = IEEE80211_SKB_CB(skb);
484
485	carl9170_tx_bar_status(ar, skb, txinfo);
486
487	if (success)
488		txinfo->flags |= IEEE80211_TX_STAT_ACK;
489	else
490		ar->tx_ack_failures++;
491
492	if (txinfo->flags & IEEE80211_TX_CTL_AMPDU)
493		carl9170_tx_status_process_ampdu(ar, skb, txinfo);
494
495	carl9170_tx_ps_unblock(ar, skb);
496	carl9170_tx_put_skb(skb);
497}
498
499/* This function may be called form any context */
500void carl9170_tx_callback(struct ar9170 *ar, struct sk_buff *skb)
501{
502	struct ieee80211_tx_info *txinfo = IEEE80211_SKB_CB(skb);
503
504	atomic_dec(&ar->tx_total_pending);
505
506	if (txinfo->flags & IEEE80211_TX_CTL_AMPDU)
507		atomic_dec(&ar->tx_ampdu_upload);
508
509	if (carl9170_tx_put_skb(skb))
510		tasklet_hi_schedule(&ar->usb_tasklet);
511}
512
513static struct sk_buff *carl9170_get_queued_skb(struct ar9170 *ar, u8 cookie,
514					       struct sk_buff_head *queue)
515{
516	struct sk_buff *skb;
517
518	spin_lock_bh(&queue->lock);
519	skb_queue_walk(queue, skb) {
520		struct _carl9170_tx_superframe *txc = (void *) skb->data;
521
522		if (txc->s.cookie != cookie)
523			continue;
524
525		__skb_unlink(skb, queue);
526		spin_unlock_bh(&queue->lock);
527
528		carl9170_release_dev_space(ar, skb);
529		return skb;
530	}
531	spin_unlock_bh(&queue->lock);
532
533	return NULL;
534}
535
536static void carl9170_tx_fill_rateinfo(struct ar9170 *ar, unsigned int rix,
537	unsigned int tries, struct ieee80211_tx_info *txinfo)
538{
539	unsigned int i;
540
541	for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
542		if (txinfo->status.rates[i].idx < 0)
543			break;
544
545		if (i == rix) {
546			txinfo->status.rates[i].count = tries;
547			i++;
548			break;
549		}
550	}
551
552	for (; i < IEEE80211_TX_MAX_RATES; i++) {
553		txinfo->status.rates[i].idx = -1;
554		txinfo->status.rates[i].count = 0;
555	}
556}
557
558static void carl9170_check_queue_stop_timeout(struct ar9170 *ar)
559{
560	int i;
561	struct sk_buff *skb;
562	struct ieee80211_tx_info *txinfo;
563	struct carl9170_tx_info *arinfo;
564	bool restart = false;
565
566	for (i = 0; i < ar->hw->queues; i++) {
567		spin_lock_bh(&ar->tx_status[i].lock);
568
569		skb = skb_peek(&ar->tx_status[i]);
570
571		if (!skb)
572			goto next;
573
574		txinfo = IEEE80211_SKB_CB(skb);
575		arinfo = (void *) txinfo->rate_driver_data;
576
577		if (time_is_before_jiffies(arinfo->timeout +
578		    msecs_to_jiffies(CARL9170_QUEUE_STUCK_TIMEOUT)) == true)
579			restart = true;
580
581next:
582		spin_unlock_bh(&ar->tx_status[i].lock);
583	}
584
585	if (restart) {
586		/*
587		 * At least one queue has been stuck for long enough.
588		 * Give the device a kick and hope it gets back to
589		 * work.
590		 *
591		 * possible reasons may include:
592		 *  - frames got lost/corrupted (bad connection to the device)
593		 *  - stalled rx processing/usb controller hiccups
594		 *  - firmware errors/bugs
595		 *  - every bug you can think of.
596		 *  - all bugs you can't...
597		 *  - ...
598		 */
599		carl9170_restart(ar, CARL9170_RR_STUCK_TX);
600	}
601}
602
603static void carl9170_tx_ampdu_timeout(struct ar9170 *ar)
604{
605	struct carl9170_sta_tid *iter;
606	struct sk_buff *skb;
607	struct ieee80211_tx_info *txinfo;
608	struct carl9170_tx_info *arinfo;
609	struct ieee80211_sta *sta;
610
611	rcu_read_lock();
612	list_for_each_entry_rcu(iter, &ar->tx_ampdu_list, list) {
613		if (iter->state < CARL9170_TID_STATE_IDLE)
614			continue;
615
616		spin_lock_bh(&iter->lock);
617		skb = skb_peek(&iter->queue);
618		if (!skb)
619			goto unlock;
620
621		txinfo = IEEE80211_SKB_CB(skb);
622		arinfo = (void *)txinfo->rate_driver_data;
623		if (time_is_after_jiffies(arinfo->timeout +
624		    msecs_to_jiffies(CARL9170_QUEUE_TIMEOUT)))
625			goto unlock;
626
627		sta = iter->sta;
628		if (WARN_ON(!sta))
629			goto unlock;
630
631		ieee80211_stop_tx_ba_session(sta, iter->tid);
632unlock:
633		spin_unlock_bh(&iter->lock);
634
635	}
636	rcu_read_unlock();
637}
638
639void carl9170_tx_janitor(struct work_struct *work)
640{
641	struct ar9170 *ar = container_of(work, struct ar9170,
642					 tx_janitor.work);
643	if (!IS_STARTED(ar))
644		return;
645
646	ar->tx_janitor_last_run = jiffies;
647
648	carl9170_check_queue_stop_timeout(ar);
649	carl9170_tx_ampdu_timeout(ar);
650
651	if (!atomic_read(&ar->tx_total_queued))
652		return;
653
654	ieee80211_queue_delayed_work(ar->hw, &ar->tx_janitor,
655		msecs_to_jiffies(CARL9170_TX_TIMEOUT));
656}
657
658static void __carl9170_tx_process_status(struct ar9170 *ar,
659	const uint8_t cookie, const uint8_t info)
660{
661	struct sk_buff *skb;
662	struct ieee80211_tx_info *txinfo;
663	unsigned int r, t, q;
664	bool success = true;
665
666	q = ar9170_qmap(info & CARL9170_TX_STATUS_QUEUE);
667
668	skb = carl9170_get_queued_skb(ar, cookie, &ar->tx_status[q]);
669	if (!skb) {
670		/*
671		 * We have lost the race to another thread.
672		 */
673
674		return ;
675	}
676
677	txinfo = IEEE80211_SKB_CB(skb);
678
679	if (!(info & CARL9170_TX_STATUS_SUCCESS))
680		success = false;
681
682	r = (info & CARL9170_TX_STATUS_RIX) >> CARL9170_TX_STATUS_RIX_S;
683	t = (info & CARL9170_TX_STATUS_TRIES) >> CARL9170_TX_STATUS_TRIES_S;
684
685	carl9170_tx_fill_rateinfo(ar, r, t, txinfo);
686	carl9170_tx_status(ar, skb, success);
687}
688
689void carl9170_tx_process_status(struct ar9170 *ar,
690				const struct carl9170_rsp *cmd)
691{
692	unsigned int i;
693
694	for (i = 0;  i < cmd->hdr.ext; i++) {
695		if (WARN_ON(i > ((cmd->hdr.len / 2) + 1))) {
696			print_hex_dump_bytes("UU:", DUMP_PREFIX_NONE,
697					     (void *) cmd, cmd->hdr.len + 4);
698			break;
699		}
700
701		__carl9170_tx_process_status(ar, cmd->_tx_status[i].cookie,
702					     cmd->_tx_status[i].info);
703	}
704}
705
706static void carl9170_tx_rate_tpc_chains(struct ar9170 *ar,
707	struct ieee80211_tx_info *info,	struct ieee80211_tx_rate *txrate,
708	unsigned int *phyrate, unsigned int *tpc, unsigned int *chains)
709{
710	struct ieee80211_rate *rate = NULL;
711	u8 *txpower;
712	unsigned int idx;
713
714	idx = txrate->idx;
715	*tpc = 0;
716	*phyrate = 0;
717
718	if (txrate->flags & IEEE80211_TX_RC_MCS) {
719		if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
720			/* +1 dBm for HT40 */
721			*tpc += 2;
722
723			if (info->band == NL80211_BAND_2GHZ)
724				txpower = ar->power_2G_ht40;
725			else
726				txpower = ar->power_5G_ht40;
727		} else {
728			if (info->band == NL80211_BAND_2GHZ)
729				txpower = ar->power_2G_ht20;
730			else
731				txpower = ar->power_5G_ht20;
732		}
733
734		*phyrate = txrate->idx;
735		*tpc += txpower[idx & 7];
736	} else {
737		if (info->band == NL80211_BAND_2GHZ) {
738			if (idx < 4)
739				txpower = ar->power_2G_cck;
740			else
741				txpower = ar->power_2G_ofdm;
742		} else {
743			txpower = ar->power_5G_leg;
744			idx += 4;
745		}
746
747		rate = &__carl9170_ratetable[idx];
748		*tpc += txpower[(rate->hw_value & 0x30) >> 4];
749		*phyrate = rate->hw_value & 0xf;
750	}
751
752	if (ar->eeprom.tx_mask == 1) {
753		*chains = AR9170_TX_PHY_TXCHAIN_1;
754	} else {
755		if (!(txrate->flags & IEEE80211_TX_RC_MCS) &&
756		    rate && rate->bitrate >= 360)
757			*chains = AR9170_TX_PHY_TXCHAIN_1;
758		else
759			*chains = AR9170_TX_PHY_TXCHAIN_2;
760	}
761
762	*tpc = min_t(unsigned int, *tpc, ar->hw->conf.power_level * 2);
763}
764
765static __le32 carl9170_tx_physet(struct ar9170 *ar,
766	struct ieee80211_tx_info *info, struct ieee80211_tx_rate *txrate)
767{
768	unsigned int power = 0, chains = 0, phyrate = 0;
769	__le32 tmp;
770
771	tmp = cpu_to_le32(0);
772
773	if (txrate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
774		tmp |= cpu_to_le32(AR9170_TX_PHY_BW_40MHZ <<
775			AR9170_TX_PHY_BW_S);
776	/* this works because 40 MHz is 2 and dup is 3 */
777	if (txrate->flags & IEEE80211_TX_RC_DUP_DATA)
778		tmp |= cpu_to_le32(AR9170_TX_PHY_BW_40MHZ_DUP <<
779			AR9170_TX_PHY_BW_S);
780
781	if (txrate->flags & IEEE80211_TX_RC_SHORT_GI)
782		tmp |= cpu_to_le32(AR9170_TX_PHY_SHORT_GI);
783
784	if (txrate->flags & IEEE80211_TX_RC_MCS) {
785		SET_VAL(AR9170_TX_PHY_MCS, phyrate, txrate->idx);
786
787		/* heavy clip control */
788		tmp |= cpu_to_le32((txrate->idx & 0x7) <<
789			AR9170_TX_PHY_TX_HEAVY_CLIP_S);
790
791		tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_HT);
792
793		/*
794		 * green field preamble does not work.
795		 *
796		 * if (txrate->flags & IEEE80211_TX_RC_GREEN_FIELD)
797		 * tmp |= cpu_to_le32(AR9170_TX_PHY_GREENFIELD);
798		 */
799	} else {
800		if (info->band == NL80211_BAND_2GHZ) {
801			if (txrate->idx <= AR9170_TX_PHY_RATE_CCK_11M)
802				tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_CCK);
803			else
804				tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_OFDM);
805		} else {
806			tmp |= cpu_to_le32(AR9170_TX_PHY_MOD_OFDM);
807		}
808
809		/*
810		 * short preamble seems to be broken too.
811		 *
812		 * if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
813		 *	tmp |= cpu_to_le32(AR9170_TX_PHY_SHORT_PREAMBLE);
814		 */
815	}
816	carl9170_tx_rate_tpc_chains(ar, info, txrate,
817				    &phyrate, &power, &chains);
818
819	tmp |= cpu_to_le32(SET_CONSTVAL(AR9170_TX_PHY_MCS, phyrate));
820	tmp |= cpu_to_le32(SET_CONSTVAL(AR9170_TX_PHY_TX_PWR, power));
821	tmp |= cpu_to_le32(SET_CONSTVAL(AR9170_TX_PHY_TXCHAIN, chains));
822	return tmp;
823}
824
825static bool carl9170_tx_rts_check(struct ar9170 *ar,
826				  struct ieee80211_tx_rate *rate,
827				  bool ampdu, bool multi)
828{
829	switch (ar->erp_mode) {
830	case CARL9170_ERP_AUTO:
831		if (ampdu)
832			break;
833		fallthrough;
834
835	case CARL9170_ERP_MAC80211:
836		if (!(rate->flags & IEEE80211_TX_RC_USE_RTS_CTS))
837			break;
838		fallthrough;
839
840	case CARL9170_ERP_RTS:
841		if (likely(!multi))
842			return true;
843
844	default:
845		break;
846	}
847
848	return false;
849}
850
851static bool carl9170_tx_cts_check(struct ar9170 *ar,
852				  struct ieee80211_tx_rate *rate)
853{
854	switch (ar->erp_mode) {
855	case CARL9170_ERP_AUTO:
856	case CARL9170_ERP_MAC80211:
857		if (!(rate->flags & IEEE80211_TX_RC_USE_CTS_PROTECT))
858			break;
859		fallthrough;
860
861	case CARL9170_ERP_CTS:
862		return true;
863
864	default:
865		break;
866	}
867
868	return false;
869}
870
871static void carl9170_tx_get_rates(struct ar9170 *ar,
872				  struct ieee80211_vif *vif,
873				  struct ieee80211_sta *sta,
874				  struct sk_buff *skb)
875{
876	struct ieee80211_tx_info *info;
877
878	BUILD_BUG_ON(IEEE80211_TX_MAX_RATES < CARL9170_TX_MAX_RATES);
879	BUILD_BUG_ON(IEEE80211_TX_MAX_RATES > IEEE80211_TX_RATE_TABLE_SIZE);
880
881	info = IEEE80211_SKB_CB(skb);
882
883	ieee80211_get_tx_rates(vif, sta, skb,
884			       info->control.rates,
885			       IEEE80211_TX_MAX_RATES);
886}
887
888static void carl9170_tx_apply_rateset(struct ar9170 *ar,
889				      struct ieee80211_tx_info *sinfo,
890				      struct sk_buff *skb)
891{
892	struct ieee80211_tx_rate *txrate;
893	struct ieee80211_tx_info *info;
894	struct _carl9170_tx_superframe *txc = (void *) skb->data;
895	int i;
896	bool ampdu;
897	bool no_ack;
898
899	info = IEEE80211_SKB_CB(skb);
900	ampdu = !!(info->flags & IEEE80211_TX_CTL_AMPDU);
901	no_ack = !!(info->flags & IEEE80211_TX_CTL_NO_ACK);
902
903	/* Set the rate control probe flag for all (sub-) frames.
904	 * This is because the TX_STATS_AMPDU flag is only set on
905	 * the last frame, so it has to be inherited.
906	 */
907	info->flags |= (sinfo->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE);
908
909	/* NOTE: For the first rate, the ERP & AMPDU flags are directly
910	 * taken from mac_control. For all fallback rate, the firmware
911	 * updates the mac_control flags from the rate info field.
912	 */
913	for (i = 0; i < CARL9170_TX_MAX_RATES; i++) {
914		__le32 phy_set;
915
916		txrate = &sinfo->control.rates[i];
917		if (txrate->idx < 0)
918			break;
919
920		phy_set = carl9170_tx_physet(ar, info, txrate);
921		if (i == 0) {
922			__le16 mac_tmp = cpu_to_le16(0);
923
924			/* first rate - part of the hw's frame header */
925			txc->f.phy_control = phy_set;
926
927			if (ampdu && txrate->flags & IEEE80211_TX_RC_MCS)
928				mac_tmp |= cpu_to_le16(AR9170_TX_MAC_AGGR);
929
930			if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
931				mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_RTS);
932			else if (carl9170_tx_cts_check(ar, txrate))
933				mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_CTS);
934
935			txc->f.mac_control |= mac_tmp;
936		} else {
937			/* fallback rates are stored in the firmware's
938			 * retry rate set array.
939			 */
940			txc->s.rr[i - 1] = phy_set;
941		}
942
943		SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[i],
944			txrate->count);
945
946		if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
947			txc->s.ri[i] |= (AR9170_TX_MAC_PROT_RTS <<
948				CARL9170_TX_SUPER_RI_ERP_PROT_S);
949		else if (carl9170_tx_cts_check(ar, txrate))
950			txc->s.ri[i] |= (AR9170_TX_MAC_PROT_CTS <<
951				CARL9170_TX_SUPER_RI_ERP_PROT_S);
952
953		if (ampdu && (txrate->flags & IEEE80211_TX_RC_MCS))
954			txc->s.ri[i] |= CARL9170_TX_SUPER_RI_AMPDU;
955	}
956}
957
958static int carl9170_tx_prepare(struct ar9170 *ar,
959			       struct ieee80211_sta *sta,
960			       struct sk_buff *skb)
961{
962	struct ieee80211_hdr *hdr;
963	struct _carl9170_tx_superframe *txc;
964	struct carl9170_vif_info *cvif;
965	struct ieee80211_tx_info *info;
966	struct carl9170_tx_info *arinfo;
967	unsigned int hw_queue;
968	__le16 mac_tmp;
969	u16 len;
970
971	BUILD_BUG_ON(sizeof(*arinfo) > sizeof(info->rate_driver_data));
972	BUILD_BUG_ON(sizeof(struct _carl9170_tx_superdesc) !=
973		     CARL9170_TX_SUPERDESC_LEN);
974
975	BUILD_BUG_ON(sizeof(struct _ar9170_tx_hwdesc) !=
976		     AR9170_TX_HWDESC_LEN);
977
978	BUILD_BUG_ON(AR9170_MAX_VIRTUAL_MAC >
979		((CARL9170_TX_SUPER_MISC_VIF_ID >>
980		 CARL9170_TX_SUPER_MISC_VIF_ID_S) + 1));
981
982	hw_queue = ar9170_qmap(carl9170_get_queue(ar, skb));
983
984	hdr = (void *)skb->data;
985	info = IEEE80211_SKB_CB(skb);
986	len = skb->len;
987
988	/*
989	 * Note: If the frame was sent through a monitor interface,
990	 * the ieee80211_vif pointer can be NULL.
991	 */
992	if (likely(info->control.vif))
993		cvif = (void *) info->control.vif->drv_priv;
994	else
995		cvif = NULL;
996
997	txc = skb_push(skb, sizeof(*txc));
998	memset(txc, 0, sizeof(*txc));
999
1000	SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, txc->s.misc, hw_queue);
1001
1002	if (likely(cvif))
1003		SET_VAL(CARL9170_TX_SUPER_MISC_VIF_ID, txc->s.misc, cvif->id);
1004
1005	if (unlikely(info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM))
1006		txc->s.misc |= CARL9170_TX_SUPER_MISC_CAB;
1007
1008	if (unlikely(info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ))
1009		txc->s.misc |= CARL9170_TX_SUPER_MISC_ASSIGN_SEQ;
1010
1011	if (unlikely(ieee80211_is_probe_resp(hdr->frame_control)))
1012		txc->s.misc |= CARL9170_TX_SUPER_MISC_FILL_IN_TSF;
1013
1014	mac_tmp = cpu_to_le16(AR9170_TX_MAC_HW_DURATION |
1015			      AR9170_TX_MAC_BACKOFF);
1016	mac_tmp |= cpu_to_le16((hw_queue << AR9170_TX_MAC_QOS_S) &
1017			       AR9170_TX_MAC_QOS);
1018
1019	if (unlikely(info->flags & IEEE80211_TX_CTL_NO_ACK))
1020		mac_tmp |= cpu_to_le16(AR9170_TX_MAC_NO_ACK);
1021
1022	if (info->control.hw_key) {
1023		len += info->control.hw_key->icv_len;
1024
1025		switch (info->control.hw_key->cipher) {
1026		case WLAN_CIPHER_SUITE_WEP40:
1027		case WLAN_CIPHER_SUITE_WEP104:
1028		case WLAN_CIPHER_SUITE_TKIP:
1029			mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_RC4);
1030			break;
1031		case WLAN_CIPHER_SUITE_CCMP:
1032			mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_AES);
1033			break;
1034		default:
1035			WARN_ON(1);
1036			goto err_out;
1037		}
1038	}
1039
1040	if (info->flags & IEEE80211_TX_CTL_AMPDU) {
1041		unsigned int density, factor;
1042
1043		if (unlikely(!sta || !cvif))
1044			goto err_out;
1045
1046		factor = min_t(unsigned int, 1u, sta->ht_cap.ampdu_factor);
1047		density = sta->ht_cap.ampdu_density;
1048
1049		if (density) {
1050			/*
1051			 * Watch out!
1052			 *
1053			 * Otus uses slightly different density values than
1054			 * those from the 802.11n spec.
1055			 */
1056
1057			density = max_t(unsigned int, density + 1, 7u);
1058		}
1059
1060		SET_VAL(CARL9170_TX_SUPER_AMPDU_DENSITY,
1061			txc->s.ampdu_settings, density);
1062
1063		SET_VAL(CARL9170_TX_SUPER_AMPDU_FACTOR,
1064			txc->s.ampdu_settings, factor);
1065	}
1066
1067	txc->s.len = cpu_to_le16(skb->len);
1068	txc->f.length = cpu_to_le16(len + FCS_LEN);
1069	txc->f.mac_control = mac_tmp;
1070
1071	arinfo = (void *)info->rate_driver_data;
1072	arinfo->timeout = jiffies;
1073	arinfo->ar = ar;
1074	kref_init(&arinfo->ref);
1075	return 0;
1076
1077err_out:
1078	skb_pull(skb, sizeof(*txc));
1079	return -EINVAL;
1080}
1081
1082static void carl9170_set_immba(struct ar9170 *ar, struct sk_buff *skb)
1083{
1084	struct _carl9170_tx_superframe *super;
1085
1086	super = (void *) skb->data;
1087	super->f.mac_control |= cpu_to_le16(AR9170_TX_MAC_IMM_BA);
1088}
1089
1090static void carl9170_set_ampdu_params(struct ar9170 *ar, struct sk_buff *skb)
1091{
1092	struct _carl9170_tx_superframe *super;
1093	int tmp;
1094
1095	super = (void *) skb->data;
1096
1097	tmp = (super->s.ampdu_settings & CARL9170_TX_SUPER_AMPDU_DENSITY) <<
1098		CARL9170_TX_SUPER_AMPDU_DENSITY_S;
1099
1100	/*
1101	 * If you haven't noticed carl9170_tx_prepare has already filled
1102	 * in all ampdu spacing & factor parameters.
1103	 * Now it's the time to check whenever the settings have to be
1104	 * updated by the firmware, or if everything is still the same.
1105	 *
1106	 * There's no sane way to handle different density values with
1107	 * this hardware, so we may as well just do the compare in the
1108	 * driver.
1109	 */
1110
1111	if (tmp != ar->current_density) {
1112		ar->current_density = tmp;
1113		super->s.ampdu_settings |=
1114			CARL9170_TX_SUPER_AMPDU_COMMIT_DENSITY;
1115	}
1116
1117	tmp = (super->s.ampdu_settings & CARL9170_TX_SUPER_AMPDU_FACTOR) <<
1118		CARL9170_TX_SUPER_AMPDU_FACTOR_S;
1119
1120	if (tmp != ar->current_factor) {
1121		ar->current_factor = tmp;
1122		super->s.ampdu_settings |=
1123			CARL9170_TX_SUPER_AMPDU_COMMIT_FACTOR;
1124	}
1125}
1126
1127static void carl9170_tx_ampdu(struct ar9170 *ar)
1128{
1129	struct sk_buff_head agg;
1130	struct carl9170_sta_tid *tid_info;
1131	struct sk_buff *skb, *first;
1132	struct ieee80211_tx_info *tx_info_first;
1133	unsigned int i = 0, done_ampdus = 0;
1134	u16 seq, queue, tmpssn;
1135
1136	atomic_inc(&ar->tx_ampdu_scheduler);
1137	ar->tx_ampdu_schedule = false;
1138
1139	if (atomic_read(&ar->tx_ampdu_upload))
1140		return;
1141
1142	if (!ar->tx_ampdu_list_len)
1143		return;
1144
1145	__skb_queue_head_init(&agg);
1146
1147	rcu_read_lock();
1148	tid_info = rcu_dereference(ar->tx_ampdu_iter);
1149	if (WARN_ON_ONCE(!tid_info)) {
1150		rcu_read_unlock();
1151		return;
1152	}
1153
1154retry:
1155	list_for_each_entry_continue_rcu(tid_info, &ar->tx_ampdu_list, list) {
1156		i++;
1157
1158		if (tid_info->state < CARL9170_TID_STATE_PROGRESS)
1159			continue;
1160
1161		queue = TID_TO_WME_AC(tid_info->tid);
1162
1163		spin_lock_bh(&tid_info->lock);
1164		if (tid_info->state != CARL9170_TID_STATE_XMIT)
1165			goto processed;
1166
1167		tid_info->counter++;
1168		first = skb_peek(&tid_info->queue);
1169		tmpssn = carl9170_get_seq(first);
1170		seq = tid_info->snx;
1171
1172		if (unlikely(tmpssn != seq)) {
1173			tid_info->state = CARL9170_TID_STATE_IDLE;
1174
1175			goto processed;
1176		}
1177
1178		tx_info_first = NULL;
1179		while ((skb = skb_peek(&tid_info->queue))) {
1180			/* strict 0, 1, ..., n - 1, n frame sequence order */
1181			if (unlikely(carl9170_get_seq(skb) != seq))
1182				break;
1183
1184			/* don't upload more than AMPDU FACTOR allows. */
1185			if (unlikely(SEQ_DIFF(tid_info->snx, tid_info->bsn) >=
1186			    (tid_info->max - 1)))
1187				break;
1188
1189			if (!tx_info_first) {
1190				carl9170_tx_get_rates(ar, tid_info->vif,
1191						      tid_info->sta, first);
1192				tx_info_first = IEEE80211_SKB_CB(first);
1193			}
1194
1195			carl9170_tx_apply_rateset(ar, tx_info_first, skb);
1196
1197			atomic_inc(&ar->tx_ampdu_upload);
1198			tid_info->snx = seq = SEQ_NEXT(seq);
1199			__skb_unlink(skb, &tid_info->queue);
1200
1201			__skb_queue_tail(&agg, skb);
1202
1203			if (skb_queue_len(&agg) >= CARL9170_NUM_TX_AGG_MAX)
1204				break;
1205		}
1206
1207		if (skb_queue_empty(&tid_info->queue) ||
1208		    carl9170_get_seq(skb_peek(&tid_info->queue)) !=
1209		    tid_info->snx) {
1210			/* stop TID, if A-MPDU frames are still missing,
1211			 * or whenever the queue is empty.
1212			 */
1213
1214			tid_info->state = CARL9170_TID_STATE_IDLE;
1215		}
1216		done_ampdus++;
1217
1218processed:
1219		spin_unlock_bh(&tid_info->lock);
1220
1221		if (skb_queue_empty(&agg))
1222			continue;
1223
1224		/* apply ampdu spacing & factor settings */
1225		carl9170_set_ampdu_params(ar, skb_peek(&agg));
1226
1227		/* set aggregation push bit */
1228		carl9170_set_immba(ar, skb_peek_tail(&agg));
1229
1230		spin_lock_bh(&ar->tx_pending[queue].lock);
1231		skb_queue_splice_tail_init(&agg, &ar->tx_pending[queue]);
1232		spin_unlock_bh(&ar->tx_pending[queue].lock);
1233		ar->tx_schedule = true;
1234	}
1235	if ((done_ampdus++ == 0) && (i++ == 0))
1236		goto retry;
1237
1238	rcu_assign_pointer(ar->tx_ampdu_iter, tid_info);
1239	rcu_read_unlock();
1240}
1241
1242static struct sk_buff *carl9170_tx_pick_skb(struct ar9170 *ar,
1243					    struct sk_buff_head *queue)
1244{
1245	struct sk_buff *skb;
1246	struct ieee80211_tx_info *info;
1247	struct carl9170_tx_info *arinfo;
1248
1249	BUILD_BUG_ON(sizeof(*arinfo) > sizeof(info->rate_driver_data));
1250
1251	spin_lock_bh(&queue->lock);
1252	skb = skb_peek(queue);
1253	if (unlikely(!skb))
1254		goto err_unlock;
1255
1256	if (carl9170_alloc_dev_space(ar, skb))
1257		goto err_unlock;
1258
1259	__skb_unlink(skb, queue);
1260	spin_unlock_bh(&queue->lock);
1261
1262	info = IEEE80211_SKB_CB(skb);
1263	arinfo = (void *) info->rate_driver_data;
1264
1265	arinfo->timeout = jiffies;
1266	return skb;
1267
1268err_unlock:
1269	spin_unlock_bh(&queue->lock);
1270	return NULL;
1271}
1272
1273void carl9170_tx_drop(struct ar9170 *ar, struct sk_buff *skb)
1274{
1275	struct _carl9170_tx_superframe *super;
1276	uint8_t q = 0;
1277
1278	ar->tx_dropped++;
1279
1280	super = (void *)skb->data;
1281	SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, q,
1282		ar9170_qmap(carl9170_get_queue(ar, skb)));
1283	__carl9170_tx_process_status(ar, super->s.cookie, q);
1284}
1285
1286static bool carl9170_tx_ps_drop(struct ar9170 *ar, struct sk_buff *skb)
1287{
1288	struct ieee80211_sta *sta;
1289	struct carl9170_sta_info *sta_info;
1290	struct ieee80211_tx_info *tx_info;
1291
1292	rcu_read_lock();
1293	sta = __carl9170_get_tx_sta(ar, skb);
1294	if (!sta)
1295		goto out_rcu;
1296
1297	sta_info = (void *) sta->drv_priv;
1298	tx_info = IEEE80211_SKB_CB(skb);
1299
1300	if (unlikely(sta_info->sleeping) &&
1301	    !(tx_info->flags & (IEEE80211_TX_CTL_NO_PS_BUFFER |
1302				IEEE80211_TX_CTL_CLEAR_PS_FILT))) {
1303		rcu_read_unlock();
1304
1305		if (tx_info->flags & IEEE80211_TX_CTL_AMPDU)
1306			atomic_dec(&ar->tx_ampdu_upload);
1307
1308		tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
1309		carl9170_release_dev_space(ar, skb);
1310		carl9170_tx_status(ar, skb, false);
1311		return true;
1312	}
1313
1314out_rcu:
1315	rcu_read_unlock();
1316	return false;
1317}
1318
1319static void carl9170_bar_check(struct ar9170 *ar, struct sk_buff *skb)
1320{
1321	struct _carl9170_tx_superframe *super = (void *) skb->data;
1322	struct ieee80211_bar *bar = (void *) super->frame_data;
1323
1324	if (unlikely(ieee80211_is_back_req(bar->frame_control)) &&
1325	    skb->len >= sizeof(struct ieee80211_bar)) {
1326		struct carl9170_bar_list_entry *entry;
1327		unsigned int queue = skb_get_queue_mapping(skb);
1328
1329		entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
1330		if (!WARN_ON_ONCE(!entry)) {
1331			entry->skb = skb;
1332			spin_lock_bh(&ar->bar_list_lock[queue]);
1333			list_add_tail_rcu(&entry->list, &ar->bar_list[queue]);
1334			spin_unlock_bh(&ar->bar_list_lock[queue]);
1335		}
1336	}
1337}
1338
1339static void carl9170_tx(struct ar9170 *ar)
1340{
1341	struct sk_buff *skb;
1342	unsigned int i, q;
1343	bool schedule_garbagecollector = false;
1344
1345	ar->tx_schedule = false;
1346
1347	if (unlikely(!IS_STARTED(ar)))
1348		return;
1349
1350	carl9170_usb_handle_tx_err(ar);
1351
1352	for (i = 0; i < ar->hw->queues; i++) {
1353		while (!skb_queue_empty(&ar->tx_pending[i])) {
1354			skb = carl9170_tx_pick_skb(ar, &ar->tx_pending[i]);
1355			if (unlikely(!skb))
1356				break;
1357
1358			if (unlikely(carl9170_tx_ps_drop(ar, skb)))
1359				continue;
1360
1361			carl9170_bar_check(ar, skb);
1362
1363			atomic_inc(&ar->tx_total_pending);
1364
1365			q = __carl9170_get_queue(ar, i);
1366			/*
1367			 * NB: tx_status[i] vs. tx_status[q],
1368			 * TODO: Move into pick_skb or alloc_dev_space.
1369			 */
1370			skb_queue_tail(&ar->tx_status[q], skb);
1371
1372			/*
1373			 * increase ref count to "2".
1374			 * Ref counting is the easiest way to solve the
1375			 * race between the urb's completion routine:
1376			 *	carl9170_tx_callback
1377			 * and wlan tx status functions:
1378			 *	carl9170_tx_status/janitor.
1379			 */
1380			carl9170_tx_get_skb(skb);
1381
1382			carl9170_usb_tx(ar, skb);
1383			schedule_garbagecollector = true;
1384		}
1385	}
1386
1387	if (!schedule_garbagecollector)
1388		return;
1389
1390	ieee80211_queue_delayed_work(ar->hw, &ar->tx_janitor,
1391		msecs_to_jiffies(CARL9170_TX_TIMEOUT));
1392}
1393
1394static bool carl9170_tx_ampdu_queue(struct ar9170 *ar,
1395	struct ieee80211_sta *sta, struct sk_buff *skb,
1396	struct ieee80211_tx_info *txinfo)
1397{
1398	struct carl9170_sta_info *sta_info;
1399	struct carl9170_sta_tid *agg;
1400	struct sk_buff *iter;
1401	u16 tid, seq, qseq, off;
1402	bool run = false;
1403
1404	tid = carl9170_get_tid(skb);
1405	seq = carl9170_get_seq(skb);
1406	sta_info = (void *) sta->drv_priv;
1407
1408	rcu_read_lock();
1409	agg = rcu_dereference(sta_info->agg[tid]);
1410
1411	if (!agg)
1412		goto err_unlock_rcu;
1413
1414	spin_lock_bh(&agg->lock);
1415	if (unlikely(agg->state < CARL9170_TID_STATE_IDLE))
1416		goto err_unlock;
1417
1418	/* check if sequence is within the BA window */
1419	if (unlikely(!BAW_WITHIN(agg->bsn, CARL9170_BAW_BITS, seq)))
1420		goto err_unlock;
1421
1422	if (WARN_ON_ONCE(!BAW_WITHIN(agg->snx, CARL9170_BAW_BITS, seq)))
1423		goto err_unlock;
1424
1425	off = SEQ_DIFF(seq, agg->bsn);
1426	if (WARN_ON_ONCE(test_and_set_bit(off, agg->bitmap)))
1427		goto err_unlock;
1428
1429	if (likely(BAW_WITHIN(agg->hsn, CARL9170_BAW_BITS, seq))) {
1430		__skb_queue_tail(&agg->queue, skb);
1431		agg->hsn = seq;
1432		goto queued;
1433	}
1434
1435	skb_queue_reverse_walk(&agg->queue, iter) {
1436		qseq = carl9170_get_seq(iter);
1437
1438		if (BAW_WITHIN(qseq, CARL9170_BAW_BITS, seq)) {
1439			__skb_queue_after(&agg->queue, iter, skb);
1440			goto queued;
1441		}
1442	}
1443
1444	__skb_queue_head(&agg->queue, skb);
1445queued:
1446
1447	if (unlikely(agg->state != CARL9170_TID_STATE_XMIT)) {
1448		if (agg->snx == carl9170_get_seq(skb_peek(&agg->queue))) {
1449			agg->state = CARL9170_TID_STATE_XMIT;
1450			run = true;
1451		}
1452	}
1453
1454	spin_unlock_bh(&agg->lock);
1455	rcu_read_unlock();
1456
1457	return run;
1458
1459err_unlock:
1460	spin_unlock_bh(&agg->lock);
1461
1462err_unlock_rcu:
1463	rcu_read_unlock();
1464	txinfo->flags &= ~IEEE80211_TX_CTL_AMPDU;
1465	carl9170_tx_status(ar, skb, false);
1466	ar->tx_dropped++;
1467	return false;
1468}
1469
1470void carl9170_op_tx(struct ieee80211_hw *hw,
1471		    struct ieee80211_tx_control *control,
1472		    struct sk_buff *skb)
1473{
1474	struct ar9170 *ar = hw->priv;
1475	struct ieee80211_tx_info *info;
1476	struct ieee80211_sta *sta = control->sta;
1477	struct ieee80211_vif *vif;
1478	bool run;
1479
1480	if (unlikely(!IS_STARTED(ar)))
1481		goto err_free;
1482
1483	info = IEEE80211_SKB_CB(skb);
1484	vif = info->control.vif;
1485
1486	if (unlikely(carl9170_tx_prepare(ar, sta, skb)))
1487		goto err_free;
1488
1489	carl9170_tx_accounting(ar, skb);
1490	/*
1491	 * from now on, one has to use carl9170_tx_status to free
1492	 * all ressouces which are associated with the frame.
1493	 */
1494
1495	if (sta) {
1496		struct carl9170_sta_info *stai = (void *) sta->drv_priv;
1497		atomic_inc(&stai->pending_frames);
1498	}
1499
1500	if (info->flags & IEEE80211_TX_CTL_AMPDU) {
1501		/* to static code analyzers and reviewers:
1502		 * mac80211 guarantees that a valid "sta"
1503		 * reference is present, if a frame is to
1504		 * be part of an ampdu. Hence any extra
1505		 * sta == NULL checks are redundant in this
1506		 * special case.
1507		 */
1508		run = carl9170_tx_ampdu_queue(ar, sta, skb, info);
1509		if (run)
1510			carl9170_tx_ampdu(ar);
1511
1512	} else {
1513		unsigned int queue = skb_get_queue_mapping(skb);
1514
1515		carl9170_tx_get_rates(ar, vif, sta, skb);
1516		carl9170_tx_apply_rateset(ar, info, skb);
1517		skb_queue_tail(&ar->tx_pending[queue], skb);
1518	}
1519
1520	carl9170_tx(ar);
1521	return;
1522
1523err_free:
1524	ar->tx_dropped++;
1525	ieee80211_free_txskb(ar->hw, skb);
1526}
1527
1528void carl9170_tx_scheduler(struct ar9170 *ar)
1529{
1530
1531	if (ar->tx_ampdu_schedule)
1532		carl9170_tx_ampdu(ar);
1533
1534	if (ar->tx_schedule)
1535		carl9170_tx(ar);
1536}
1537
1538/* caller has to take rcu_read_lock */
1539static struct carl9170_vif_info *carl9170_pick_beaconing_vif(struct ar9170 *ar)
1540{
1541	struct carl9170_vif_info *cvif;
1542	int i = 1;
1543
1544	/* The AR9170 hardware has no fancy beacon queue or some
1545	 * other scheduling mechanism. So, the driver has to make
1546	 * due by setting the two beacon timers (pretbtt and tbtt)
1547	 * once and then swapping the beacon address in the HW's
1548	 * register file each time the pretbtt fires.
1549	 */
1550
1551	cvif = rcu_dereference(ar->beacon_iter);
1552	if (ar->vifs > 0 && cvif) {
1553		do {
1554			list_for_each_entry_continue_rcu(cvif, &ar->vif_list,
1555							 list) {
1556				if (cvif->active && cvif->enable_beacon)
1557					goto out;
1558			}
1559		} while (ar->beacon_enabled && i--);
1560
1561		/* no entry found in list */
1562		return NULL;
1563	}
1564
1565out:
1566	RCU_INIT_POINTER(ar->beacon_iter, cvif);
1567	return cvif;
1568}
1569
1570static bool carl9170_tx_beacon_physet(struct ar9170 *ar, struct sk_buff *skb,
1571				      u32 *ht1, u32 *plcp)
1572{
1573	struct ieee80211_tx_info *txinfo;
1574	struct ieee80211_tx_rate *rate;
1575	unsigned int power, chains;
1576	bool ht_rate;
1577
1578	txinfo = IEEE80211_SKB_CB(skb);
1579	rate = &txinfo->control.rates[0];
1580	ht_rate = !!(txinfo->control.rates[0].flags & IEEE80211_TX_RC_MCS);
1581	carl9170_tx_rate_tpc_chains(ar, txinfo, rate, plcp, &power, &chains);
1582
1583	*ht1 = AR9170_MAC_BCN_HT1_TX_ANT0;
1584	if (chains == AR9170_TX_PHY_TXCHAIN_2)
1585		*ht1 |= AR9170_MAC_BCN_HT1_TX_ANT1;
1586	SET_VAL(AR9170_MAC_BCN_HT1_PWR_CTRL, *ht1, 7);
1587	SET_VAL(AR9170_MAC_BCN_HT1_TPC, *ht1, power);
1588	SET_VAL(AR9170_MAC_BCN_HT1_CHAIN_MASK, *ht1, chains);
1589
1590	if (ht_rate) {
1591		*ht1 |= AR9170_MAC_BCN_HT1_HT_EN;
1592		if (rate->flags & IEEE80211_TX_RC_SHORT_GI)
1593			*plcp |= AR9170_MAC_BCN_HT2_SGI;
1594
1595		if (rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
1596			*ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_SHARED;
1597			*plcp |= AR9170_MAC_BCN_HT2_BW40;
1598		} else if (rate->flags & IEEE80211_TX_RC_DUP_DATA) {
1599			*ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_DUP;
1600			*plcp |= AR9170_MAC_BCN_HT2_BW40;
1601		}
1602
1603		SET_VAL(AR9170_MAC_BCN_HT2_LEN, *plcp, skb->len + FCS_LEN);
1604	} else {
1605		if (*plcp <= AR9170_TX_PHY_RATE_CCK_11M)
1606			*plcp |= ((skb->len + FCS_LEN) << (3 + 16)) + 0x0400;
1607		else
1608			*plcp |= ((skb->len + FCS_LEN) << 16) + 0x0010;
1609	}
1610
1611	return ht_rate;
1612}
1613
1614int carl9170_update_beacon(struct ar9170 *ar, const bool submit)
1615{
1616	struct sk_buff *skb = NULL;
1617	struct carl9170_vif_info *cvif;
1618	__le32 *data, *old = NULL;
1619	u32 word, ht1, plcp, off, addr, len;
1620	int i = 0, err = 0;
1621	bool ht_rate;
1622
1623	rcu_read_lock();
1624	cvif = carl9170_pick_beaconing_vif(ar);
1625	if (!cvif)
1626		goto out_unlock;
1627
1628	skb = ieee80211_beacon_get_tim(ar->hw, carl9170_get_vif(cvif),
1629		NULL, NULL);
1630
1631	if (!skb) {
1632		err = -ENOMEM;
1633		goto err_free;
1634	}
1635
1636	spin_lock_bh(&ar->beacon_lock);
1637	data = (__le32 *)skb->data;
1638	if (cvif->beacon)
1639		old = (__le32 *)cvif->beacon->data;
1640
1641	off = cvif->id * AR9170_MAC_BCN_LENGTH_MAX;
1642	addr = ar->fw.beacon_addr + off;
1643	len = roundup(skb->len + FCS_LEN, 4);
1644
1645	if ((off + len) > ar->fw.beacon_max_len) {
1646		if (net_ratelimit()) {
1647			wiphy_err(ar->hw->wiphy, "beacon does not "
1648				  "fit into device memory!\n");
1649		}
1650		err = -EINVAL;
1651		goto err_unlock;
1652	}
1653
1654	if (len > AR9170_MAC_BCN_LENGTH_MAX) {
1655		if (net_ratelimit()) {
1656			wiphy_err(ar->hw->wiphy, "no support for beacons "
1657				"bigger than %d (yours:%d).\n",
1658				 AR9170_MAC_BCN_LENGTH_MAX, len);
1659		}
1660
1661		err = -EMSGSIZE;
1662		goto err_unlock;
1663	}
1664
1665	ht_rate = carl9170_tx_beacon_physet(ar, skb, &ht1, &plcp);
1666
1667	carl9170_async_regwrite_begin(ar);
1668	carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT1, ht1);
1669	if (ht_rate)
1670		carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT2, plcp);
1671	else
1672		carl9170_async_regwrite(AR9170_MAC_REG_BCN_PLCP, plcp);
1673
1674	for (i = 0; i < DIV_ROUND_UP(skb->len, 4); i++) {
1675		/*
1676		 * XXX: This accesses beyond skb data for up
1677		 *	to the last 3 bytes!!
1678		 */
1679
1680		if (old && (data[i] == old[i]))
1681			continue;
1682
1683		word = le32_to_cpu(data[i]);
1684		carl9170_async_regwrite(addr + 4 * i, word);
1685	}
1686	carl9170_async_regwrite_finish();
1687
1688	dev_kfree_skb_any(cvif->beacon);
1689	cvif->beacon = NULL;
1690
1691	err = carl9170_async_regwrite_result();
1692	if (!err)
1693		cvif->beacon = skb;
1694	spin_unlock_bh(&ar->beacon_lock);
1695	if (err)
1696		goto err_free;
1697
1698	if (submit) {
1699		err = carl9170_bcn_ctrl(ar, cvif->id,
1700					CARL9170_BCN_CTRL_CAB_TRIGGER,
1701					addr, skb->len + FCS_LEN);
1702
1703		if (err)
1704			goto err_free;
1705	}
1706out_unlock:
1707	rcu_read_unlock();
1708	return 0;
1709
1710err_unlock:
1711	spin_unlock_bh(&ar->beacon_lock);
1712
1713err_free:
1714	rcu_read_unlock();
1715	dev_kfree_skb_any(skb);
1716	return err;
1717}
1718