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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 (unlikely(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 == IEEE80211_BAND_2GHZ)
724				txpower = ar->power_2G_ht40;
725			else
726				txpower = ar->power_5G_ht40;
727		} else {
728			if (info->band == IEEE80211_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 == IEEE80211_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 == IEEE80211_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
834	case CARL9170_ERP_MAC80211:
835		if (!(rate->flags & IEEE80211_TX_RC_USE_RTS_CTS))
836			break;
837
838	case CARL9170_ERP_RTS:
839		if (likely(!multi))
840			return true;
841
842	default:
843		break;
844	}
845
846	return false;
847}
848
849static bool carl9170_tx_cts_check(struct ar9170 *ar,
850				  struct ieee80211_tx_rate *rate)
851{
852	switch (ar->erp_mode) {
853	case CARL9170_ERP_AUTO:
854	case CARL9170_ERP_MAC80211:
855		if (!(rate->flags & IEEE80211_TX_RC_USE_CTS_PROTECT))
856			break;
857
858	case CARL9170_ERP_CTS:
859		return true;
860
861	default:
862		break;
863	}
864
865	return false;
866}
867
868static void carl9170_tx_get_rates(struct ar9170 *ar,
869				  struct ieee80211_vif *vif,
870				  struct ieee80211_sta *sta,
871				  struct sk_buff *skb)
872{
873	struct ieee80211_tx_info *info;
874
875	BUILD_BUG_ON(IEEE80211_TX_MAX_RATES < CARL9170_TX_MAX_RATES);
876	BUILD_BUG_ON(IEEE80211_TX_MAX_RATES > IEEE80211_TX_RATE_TABLE_SIZE);
877
878	info = IEEE80211_SKB_CB(skb);
879
880	ieee80211_get_tx_rates(vif, sta, skb,
881			       info->control.rates,
882			       IEEE80211_TX_MAX_RATES);
883}
884
885static void carl9170_tx_apply_rateset(struct ar9170 *ar,
886				      struct ieee80211_tx_info *sinfo,
887				      struct sk_buff *skb)
888{
889	struct ieee80211_tx_rate *txrate;
890	struct ieee80211_tx_info *info;
891	struct _carl9170_tx_superframe *txc = (void *) skb->data;
892	int i;
893	bool ampdu;
894	bool no_ack;
895
896	info = IEEE80211_SKB_CB(skb);
897	ampdu = !!(info->flags & IEEE80211_TX_CTL_AMPDU);
898	no_ack = !!(info->flags & IEEE80211_TX_CTL_NO_ACK);
899
900	/* Set the rate control probe flag for all (sub-) frames.
901	 * This is because the TX_STATS_AMPDU flag is only set on
902	 * the last frame, so it has to be inherited.
903	 */
904	info->flags |= (sinfo->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE);
905
906	/* NOTE: For the first rate, the ERP & AMPDU flags are directly
907	 * taken from mac_control. For all fallback rate, the firmware
908	 * updates the mac_control flags from the rate info field.
909	 */
910	for (i = 0; i < CARL9170_TX_MAX_RATES; i++) {
911		__le32 phy_set;
912
913		txrate = &sinfo->control.rates[i];
914		if (txrate->idx < 0)
915			break;
916
917		phy_set = carl9170_tx_physet(ar, info, txrate);
918		if (i == 0) {
919			__le16 mac_tmp = cpu_to_le16(0);
920
921			/* first rate - part of the hw's frame header */
922			txc->f.phy_control = phy_set;
923
924			if (ampdu && txrate->flags & IEEE80211_TX_RC_MCS)
925				mac_tmp |= cpu_to_le16(AR9170_TX_MAC_AGGR);
926
927			if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
928				mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_RTS);
929			else if (carl9170_tx_cts_check(ar, txrate))
930				mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_CTS);
931
932			txc->f.mac_control |= mac_tmp;
933		} else {
934			/* fallback rates are stored in the firmware's
935			 * retry rate set array.
936			 */
937			txc->s.rr[i - 1] = phy_set;
938		}
939
940		SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[i],
941			txrate->count);
942
943		if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
944			txc->s.ri[i] |= (AR9170_TX_MAC_PROT_RTS <<
945				CARL9170_TX_SUPER_RI_ERP_PROT_S);
946		else if (carl9170_tx_cts_check(ar, txrate))
947			txc->s.ri[i] |= (AR9170_TX_MAC_PROT_CTS <<
948				CARL9170_TX_SUPER_RI_ERP_PROT_S);
949
950		if (ampdu && (txrate->flags & IEEE80211_TX_RC_MCS))
951			txc->s.ri[i] |= CARL9170_TX_SUPER_RI_AMPDU;
952	}
953}
954
955static int carl9170_tx_prepare(struct ar9170 *ar,
956			       struct ieee80211_sta *sta,
957			       struct sk_buff *skb)
958{
959	struct ieee80211_hdr *hdr;
960	struct _carl9170_tx_superframe *txc;
961	struct carl9170_vif_info *cvif;
962	struct ieee80211_tx_info *info;
963	struct carl9170_tx_info *arinfo;
964	unsigned int hw_queue;
965	__le16 mac_tmp;
966	u16 len;
967
968	BUILD_BUG_ON(sizeof(*arinfo) > sizeof(info->rate_driver_data));
969	BUILD_BUG_ON(sizeof(struct _carl9170_tx_superdesc) !=
970		     CARL9170_TX_SUPERDESC_LEN);
971
972	BUILD_BUG_ON(sizeof(struct _ar9170_tx_hwdesc) !=
973		     AR9170_TX_HWDESC_LEN);
974
975	BUILD_BUG_ON(AR9170_MAX_VIRTUAL_MAC >
976		((CARL9170_TX_SUPER_MISC_VIF_ID >>
977		 CARL9170_TX_SUPER_MISC_VIF_ID_S) + 1));
978
979	hw_queue = ar9170_qmap[carl9170_get_queue(ar, skb)];
980
981	hdr = (void *)skb->data;
982	info = IEEE80211_SKB_CB(skb);
983	len = skb->len;
984
985	/*
986	 * Note: If the frame was sent through a monitor interface,
987	 * the ieee80211_vif pointer can be NULL.
988	 */
989	if (likely(info->control.vif))
990		cvif = (void *) info->control.vif->drv_priv;
991	else
992		cvif = NULL;
993
994	txc = (void *)skb_push(skb, sizeof(*txc));
995	memset(txc, 0, sizeof(*txc));
996
997	SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, txc->s.misc, hw_queue);
998
999	if (likely(cvif))
1000		SET_VAL(CARL9170_TX_SUPER_MISC_VIF_ID, txc->s.misc, cvif->id);
1001
1002	if (unlikely(info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM))
1003		txc->s.misc |= CARL9170_TX_SUPER_MISC_CAB;
1004
1005	if (unlikely(info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ))
1006		txc->s.misc |= CARL9170_TX_SUPER_MISC_ASSIGN_SEQ;
1007
1008	if (unlikely(ieee80211_is_probe_resp(hdr->frame_control)))
1009		txc->s.misc |= CARL9170_TX_SUPER_MISC_FILL_IN_TSF;
1010
1011	mac_tmp = cpu_to_le16(AR9170_TX_MAC_HW_DURATION |
1012			      AR9170_TX_MAC_BACKOFF);
1013	mac_tmp |= cpu_to_le16((hw_queue << AR9170_TX_MAC_QOS_S) &
1014			       AR9170_TX_MAC_QOS);
1015
1016	if (unlikely(info->flags & IEEE80211_TX_CTL_NO_ACK))
1017		mac_tmp |= cpu_to_le16(AR9170_TX_MAC_NO_ACK);
1018
1019	if (info->control.hw_key) {
1020		len += info->control.hw_key->icv_len;
1021
1022		switch (info->control.hw_key->cipher) {
1023		case WLAN_CIPHER_SUITE_WEP40:
1024		case WLAN_CIPHER_SUITE_WEP104:
1025		case WLAN_CIPHER_SUITE_TKIP:
1026			mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_RC4);
1027			break;
1028		case WLAN_CIPHER_SUITE_CCMP:
1029			mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_AES);
1030			break;
1031		default:
1032			WARN_ON(1);
1033			goto err_out;
1034		}
1035	}
1036
1037	if (info->flags & IEEE80211_TX_CTL_AMPDU) {
1038		unsigned int density, factor;
1039
1040		if (unlikely(!sta || !cvif))
1041			goto err_out;
1042
1043		factor = min_t(unsigned int, 1u, sta->ht_cap.ampdu_factor);
1044		density = sta->ht_cap.ampdu_density;
1045
1046		if (density) {
1047			/*
1048			 * Watch out!
1049			 *
1050			 * Otus uses slightly different density values than
1051			 * those from the 802.11n spec.
1052			 */
1053
1054			density = max_t(unsigned int, density + 1, 7u);
1055		}
1056
1057		SET_VAL(CARL9170_TX_SUPER_AMPDU_DENSITY,
1058			txc->s.ampdu_settings, density);
1059
1060		SET_VAL(CARL9170_TX_SUPER_AMPDU_FACTOR,
1061			txc->s.ampdu_settings, factor);
1062	}
1063
1064	txc->s.len = cpu_to_le16(skb->len);
1065	txc->f.length = cpu_to_le16(len + FCS_LEN);
1066	txc->f.mac_control = mac_tmp;
1067
1068	arinfo = (void *)info->rate_driver_data;
1069	arinfo->timeout = jiffies;
1070	arinfo->ar = ar;
1071	kref_init(&arinfo->ref);
1072	return 0;
1073
1074err_out:
1075	skb_pull(skb, sizeof(*txc));
1076	return -EINVAL;
1077}
1078
1079static void carl9170_set_immba(struct ar9170 *ar, struct sk_buff *skb)
1080{
1081	struct _carl9170_tx_superframe *super;
1082
1083	super = (void *) skb->data;
1084	super->f.mac_control |= cpu_to_le16(AR9170_TX_MAC_IMM_BA);
1085}
1086
1087static void carl9170_set_ampdu_params(struct ar9170 *ar, struct sk_buff *skb)
1088{
1089	struct _carl9170_tx_superframe *super;
1090	int tmp;
1091
1092	super = (void *) skb->data;
1093
1094	tmp = (super->s.ampdu_settings & CARL9170_TX_SUPER_AMPDU_DENSITY) <<
1095		CARL9170_TX_SUPER_AMPDU_DENSITY_S;
1096
1097	/*
1098	 * If you haven't noticed carl9170_tx_prepare has already filled
1099	 * in all ampdu spacing & factor parameters.
1100	 * Now it's the time to check whenever the settings have to be
1101	 * updated by the firmware, or if everything is still the same.
1102	 *
1103	 * There's no sane way to handle different density values with
1104	 * this hardware, so we may as well just do the compare in the
1105	 * driver.
1106	 */
1107
1108	if (tmp != ar->current_density) {
1109		ar->current_density = tmp;
1110		super->s.ampdu_settings |=
1111			CARL9170_TX_SUPER_AMPDU_COMMIT_DENSITY;
1112	}
1113
1114	tmp = (super->s.ampdu_settings & CARL9170_TX_SUPER_AMPDU_FACTOR) <<
1115		CARL9170_TX_SUPER_AMPDU_FACTOR_S;
1116
1117	if (tmp != ar->current_factor) {
1118		ar->current_factor = tmp;
1119		super->s.ampdu_settings |=
1120			CARL9170_TX_SUPER_AMPDU_COMMIT_FACTOR;
1121	}
1122}
1123
1124static void carl9170_tx_ampdu(struct ar9170 *ar)
1125{
1126	struct sk_buff_head agg;
1127	struct carl9170_sta_tid *tid_info;
1128	struct sk_buff *skb, *first;
1129	struct ieee80211_tx_info *tx_info_first;
1130	unsigned int i = 0, done_ampdus = 0;
1131	u16 seq, queue, tmpssn;
1132
1133	atomic_inc(&ar->tx_ampdu_scheduler);
1134	ar->tx_ampdu_schedule = false;
1135
1136	if (atomic_read(&ar->tx_ampdu_upload))
1137		return;
1138
1139	if (!ar->tx_ampdu_list_len)
1140		return;
1141
1142	__skb_queue_head_init(&agg);
1143
1144	rcu_read_lock();
1145	tid_info = rcu_dereference(ar->tx_ampdu_iter);
1146	if (WARN_ON_ONCE(!tid_info)) {
1147		rcu_read_unlock();
1148		return;
1149	}
1150
1151retry:
1152	list_for_each_entry_continue_rcu(tid_info, &ar->tx_ampdu_list, list) {
1153		i++;
1154
1155		if (tid_info->state < CARL9170_TID_STATE_PROGRESS)
1156			continue;
1157
1158		queue = TID_TO_WME_AC(tid_info->tid);
1159
1160		spin_lock_bh(&tid_info->lock);
1161		if (tid_info->state != CARL9170_TID_STATE_XMIT)
1162			goto processed;
1163
1164		tid_info->counter++;
1165		first = skb_peek(&tid_info->queue);
1166		tmpssn = carl9170_get_seq(first);
1167		seq = tid_info->snx;
1168
1169		if (unlikely(tmpssn != seq)) {
1170			tid_info->state = CARL9170_TID_STATE_IDLE;
1171
1172			goto processed;
1173		}
1174
1175		tx_info_first = NULL;
1176		while ((skb = skb_peek(&tid_info->queue))) {
1177			/* strict 0, 1, ..., n - 1, n frame sequence order */
1178			if (unlikely(carl9170_get_seq(skb) != seq))
1179				break;
1180
1181			/* don't upload more than AMPDU FACTOR allows. */
1182			if (unlikely(SEQ_DIFF(tid_info->snx, tid_info->bsn) >=
1183			    (tid_info->max - 1)))
1184				break;
1185
1186			if (!tx_info_first) {
1187				carl9170_tx_get_rates(ar, tid_info->vif,
1188						      tid_info->sta, first);
1189				tx_info_first = IEEE80211_SKB_CB(first);
1190			}
1191
1192			carl9170_tx_apply_rateset(ar, tx_info_first, skb);
1193
1194			atomic_inc(&ar->tx_ampdu_upload);
1195			tid_info->snx = seq = SEQ_NEXT(seq);
1196			__skb_unlink(skb, &tid_info->queue);
1197
1198			__skb_queue_tail(&agg, skb);
1199
1200			if (skb_queue_len(&agg) >= CARL9170_NUM_TX_AGG_MAX)
1201				break;
1202		}
1203
1204		if (skb_queue_empty(&tid_info->queue) ||
1205		    carl9170_get_seq(skb_peek(&tid_info->queue)) !=
1206		    tid_info->snx) {
1207			/* stop TID, if A-MPDU frames are still missing,
1208			 * or whenever the queue is empty.
1209			 */
1210
1211			tid_info->state = CARL9170_TID_STATE_IDLE;
1212		}
1213		done_ampdus++;
1214
1215processed:
1216		spin_unlock_bh(&tid_info->lock);
1217
1218		if (skb_queue_empty(&agg))
1219			continue;
1220
1221		/* apply ampdu spacing & factor settings */
1222		carl9170_set_ampdu_params(ar, skb_peek(&agg));
1223
1224		/* set aggregation push bit */
1225		carl9170_set_immba(ar, skb_peek_tail(&agg));
1226
1227		spin_lock_bh(&ar->tx_pending[queue].lock);
1228		skb_queue_splice_tail_init(&agg, &ar->tx_pending[queue]);
1229		spin_unlock_bh(&ar->tx_pending[queue].lock);
1230		ar->tx_schedule = true;
1231	}
1232	if ((done_ampdus++ == 0) && (i++ == 0))
1233		goto retry;
1234
1235	rcu_assign_pointer(ar->tx_ampdu_iter, tid_info);
1236	rcu_read_unlock();
1237}
1238
1239static struct sk_buff *carl9170_tx_pick_skb(struct ar9170 *ar,
1240					    struct sk_buff_head *queue)
1241{
1242	struct sk_buff *skb;
1243	struct ieee80211_tx_info *info;
1244	struct carl9170_tx_info *arinfo;
1245
1246	BUILD_BUG_ON(sizeof(*arinfo) > sizeof(info->rate_driver_data));
1247
1248	spin_lock_bh(&queue->lock);
1249	skb = skb_peek(queue);
1250	if (unlikely(!skb))
1251		goto err_unlock;
1252
1253	if (carl9170_alloc_dev_space(ar, skb))
1254		goto err_unlock;
1255
1256	__skb_unlink(skb, queue);
1257	spin_unlock_bh(&queue->lock);
1258
1259	info = IEEE80211_SKB_CB(skb);
1260	arinfo = (void *) info->rate_driver_data;
1261
1262	arinfo->timeout = jiffies;
1263	return skb;
1264
1265err_unlock:
1266	spin_unlock_bh(&queue->lock);
1267	return NULL;
1268}
1269
1270void carl9170_tx_drop(struct ar9170 *ar, struct sk_buff *skb)
1271{
1272	struct _carl9170_tx_superframe *super;
1273	uint8_t q = 0;
1274
1275	ar->tx_dropped++;
1276
1277	super = (void *)skb->data;
1278	SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, q,
1279		ar9170_qmap[carl9170_get_queue(ar, skb)]);
1280	__carl9170_tx_process_status(ar, super->s.cookie, q);
1281}
1282
1283static bool carl9170_tx_ps_drop(struct ar9170 *ar, struct sk_buff *skb)
1284{
1285	struct ieee80211_sta *sta;
1286	struct carl9170_sta_info *sta_info;
1287	struct ieee80211_tx_info *tx_info;
1288
1289	rcu_read_lock();
1290	sta = __carl9170_get_tx_sta(ar, skb);
1291	if (!sta)
1292		goto out_rcu;
1293
1294	sta_info = (void *) sta->drv_priv;
1295	tx_info = IEEE80211_SKB_CB(skb);
1296
1297	if (unlikely(sta_info->sleeping) &&
1298	    !(tx_info->flags & (IEEE80211_TX_CTL_NO_PS_BUFFER |
1299				IEEE80211_TX_CTL_CLEAR_PS_FILT))) {
1300		rcu_read_unlock();
1301
1302		if (tx_info->flags & IEEE80211_TX_CTL_AMPDU)
1303			atomic_dec(&ar->tx_ampdu_upload);
1304
1305		tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
1306		carl9170_release_dev_space(ar, skb);
1307		carl9170_tx_status(ar, skb, false);
1308		return true;
1309	}
1310
1311out_rcu:
1312	rcu_read_unlock();
1313	return false;
1314}
1315
1316static void carl9170_bar_check(struct ar9170 *ar, struct sk_buff *skb)
1317{
1318	struct _carl9170_tx_superframe *super = (void *) skb->data;
1319	struct ieee80211_bar *bar = (void *) super->frame_data;
1320
1321	if (unlikely(ieee80211_is_back_req(bar->frame_control)) &&
1322	    skb->len >= sizeof(struct ieee80211_bar)) {
1323		struct carl9170_bar_list_entry *entry;
1324		unsigned int queue = skb_get_queue_mapping(skb);
1325
1326		entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
1327		if (!WARN_ON_ONCE(!entry)) {
1328			entry->skb = skb;
1329			spin_lock_bh(&ar->bar_list_lock[queue]);
1330			list_add_tail_rcu(&entry->list, &ar->bar_list[queue]);
1331			spin_unlock_bh(&ar->bar_list_lock[queue]);
1332		}
1333	}
1334}
1335
1336static void carl9170_tx(struct ar9170 *ar)
1337{
1338	struct sk_buff *skb;
1339	unsigned int i, q;
1340	bool schedule_garbagecollector = false;
1341
1342	ar->tx_schedule = false;
1343
1344	if (unlikely(!IS_STARTED(ar)))
1345		return;
1346
1347	carl9170_usb_handle_tx_err(ar);
1348
1349	for (i = 0; i < ar->hw->queues; i++) {
1350		while (!skb_queue_empty(&ar->tx_pending[i])) {
1351			skb = carl9170_tx_pick_skb(ar, &ar->tx_pending[i]);
1352			if (unlikely(!skb))
1353				break;
1354
1355			if (unlikely(carl9170_tx_ps_drop(ar, skb)))
1356				continue;
1357
1358			carl9170_bar_check(ar, skb);
1359
1360			atomic_inc(&ar->tx_total_pending);
1361
1362			q = __carl9170_get_queue(ar, i);
1363			/*
1364			 * NB: tx_status[i] vs. tx_status[q],
1365			 * TODO: Move into pick_skb or alloc_dev_space.
1366			 */
1367			skb_queue_tail(&ar->tx_status[q], skb);
1368
1369			/*
1370			 * increase ref count to "2".
1371			 * Ref counting is the easiest way to solve the
1372			 * race between the urb's completion routine:
1373			 *	carl9170_tx_callback
1374			 * and wlan tx status functions:
1375			 *	carl9170_tx_status/janitor.
1376			 */
1377			carl9170_tx_get_skb(skb);
1378
1379			carl9170_usb_tx(ar, skb);
1380			schedule_garbagecollector = true;
1381		}
1382	}
1383
1384	if (!schedule_garbagecollector)
1385		return;
1386
1387	ieee80211_queue_delayed_work(ar->hw, &ar->tx_janitor,
1388		msecs_to_jiffies(CARL9170_TX_TIMEOUT));
1389}
1390
1391static bool carl9170_tx_ampdu_queue(struct ar9170 *ar,
1392	struct ieee80211_sta *sta, struct sk_buff *skb,
1393	struct ieee80211_tx_info *txinfo)
1394{
1395	struct carl9170_sta_info *sta_info;
1396	struct carl9170_sta_tid *agg;
1397	struct sk_buff *iter;
1398	u16 tid, seq, qseq, off;
1399	bool run = false;
1400
1401	tid = carl9170_get_tid(skb);
1402	seq = carl9170_get_seq(skb);
1403	sta_info = (void *) sta->drv_priv;
1404
1405	rcu_read_lock();
1406	agg = rcu_dereference(sta_info->agg[tid]);
1407
1408	if (!agg)
1409		goto err_unlock_rcu;
1410
1411	spin_lock_bh(&agg->lock);
1412	if (unlikely(agg->state < CARL9170_TID_STATE_IDLE))
1413		goto err_unlock;
1414
1415	/* check if sequence is within the BA window */
1416	if (unlikely(!BAW_WITHIN(agg->bsn, CARL9170_BAW_BITS, seq)))
1417		goto err_unlock;
1418
1419	if (WARN_ON_ONCE(!BAW_WITHIN(agg->snx, CARL9170_BAW_BITS, seq)))
1420		goto err_unlock;
1421
1422	off = SEQ_DIFF(seq, agg->bsn);
1423	if (WARN_ON_ONCE(test_and_set_bit(off, agg->bitmap)))
1424		goto err_unlock;
1425
1426	if (likely(BAW_WITHIN(agg->hsn, CARL9170_BAW_BITS, seq))) {
1427		__skb_queue_tail(&agg->queue, skb);
1428		agg->hsn = seq;
1429		goto queued;
1430	}
1431
1432	skb_queue_reverse_walk(&agg->queue, iter) {
1433		qseq = carl9170_get_seq(iter);
1434
1435		if (BAW_WITHIN(qseq, CARL9170_BAW_BITS, seq)) {
1436			__skb_queue_after(&agg->queue, iter, skb);
1437			goto queued;
1438		}
1439	}
1440
1441	__skb_queue_head(&agg->queue, skb);
1442queued:
1443
1444	if (unlikely(agg->state != CARL9170_TID_STATE_XMIT)) {
1445		if (agg->snx == carl9170_get_seq(skb_peek(&agg->queue))) {
1446			agg->state = CARL9170_TID_STATE_XMIT;
1447			run = true;
1448		}
1449	}
1450
1451	spin_unlock_bh(&agg->lock);
1452	rcu_read_unlock();
1453
1454	return run;
1455
1456err_unlock:
1457	spin_unlock_bh(&agg->lock);
1458
1459err_unlock_rcu:
1460	rcu_read_unlock();
1461	txinfo->flags &= ~IEEE80211_TX_CTL_AMPDU;
1462	carl9170_tx_status(ar, skb, false);
1463	ar->tx_dropped++;
1464	return false;
1465}
1466
1467void carl9170_op_tx(struct ieee80211_hw *hw,
1468		    struct ieee80211_tx_control *control,
1469		    struct sk_buff *skb)
1470{
1471	struct ar9170 *ar = hw->priv;
1472	struct ieee80211_tx_info *info;
1473	struct ieee80211_sta *sta = control->sta;
1474	struct ieee80211_vif *vif;
1475	bool run;
1476
1477	if (unlikely(!IS_STARTED(ar)))
1478		goto err_free;
1479
1480	info = IEEE80211_SKB_CB(skb);
1481	vif = info->control.vif;
1482
1483	if (unlikely(carl9170_tx_prepare(ar, sta, skb)))
1484		goto err_free;
1485
1486	carl9170_tx_accounting(ar, skb);
1487	/*
1488	 * from now on, one has to use carl9170_tx_status to free
1489	 * all ressouces which are associated with the frame.
1490	 */
1491
1492	if (sta) {
1493		struct carl9170_sta_info *stai = (void *) sta->drv_priv;
1494		atomic_inc(&stai->pending_frames);
1495	}
1496
1497	if (info->flags & IEEE80211_TX_CTL_AMPDU) {
1498		/* to static code analyzers and reviewers:
1499		 * mac80211 guarantees that a valid "sta"
1500		 * reference is present, if a frame is to
1501		 * be part of an ampdu. Hence any extra
1502		 * sta == NULL checks are redundant in this
1503		 * special case.
1504		 */
1505		run = carl9170_tx_ampdu_queue(ar, sta, skb, info);
1506		if (run)
1507			carl9170_tx_ampdu(ar);
1508
1509	} else {
1510		unsigned int queue = skb_get_queue_mapping(skb);
1511
1512		carl9170_tx_get_rates(ar, vif, sta, skb);
1513		carl9170_tx_apply_rateset(ar, info, skb);
1514		skb_queue_tail(&ar->tx_pending[queue], skb);
1515	}
1516
1517	carl9170_tx(ar);
1518	return;
1519
1520err_free:
1521	ar->tx_dropped++;
1522	ieee80211_free_txskb(ar->hw, skb);
1523}
1524
1525void carl9170_tx_scheduler(struct ar9170 *ar)
1526{
1527
1528	if (ar->tx_ampdu_schedule)
1529		carl9170_tx_ampdu(ar);
1530
1531	if (ar->tx_schedule)
1532		carl9170_tx(ar);
1533}
1534
1535/* caller has to take rcu_read_lock */
1536static struct carl9170_vif_info *carl9170_pick_beaconing_vif(struct ar9170 *ar)
1537{
1538	struct carl9170_vif_info *cvif;
1539	int i = 1;
1540
1541	/* The AR9170 hardware has no fancy beacon queue or some
1542	 * other scheduling mechanism. So, the driver has to make
1543	 * due by setting the two beacon timers (pretbtt and tbtt)
1544	 * once and then swapping the beacon address in the HW's
1545	 * register file each time the pretbtt fires.
1546	 */
1547
1548	cvif = rcu_dereference(ar->beacon_iter);
1549	if (ar->vifs > 0 && cvif) {
1550		do {
1551			list_for_each_entry_continue_rcu(cvif, &ar->vif_list,
1552							 list) {
1553				if (cvif->active && cvif->enable_beacon)
1554					goto out;
1555			}
1556		} while (ar->beacon_enabled && i--);
1557	}
1558
1559out:
1560	RCU_INIT_POINTER(ar->beacon_iter, cvif);
1561	return cvif;
1562}
1563
1564static bool carl9170_tx_beacon_physet(struct ar9170 *ar, struct sk_buff *skb,
1565				      u32 *ht1, u32 *plcp)
1566{
1567	struct ieee80211_tx_info *txinfo;
1568	struct ieee80211_tx_rate *rate;
1569	unsigned int power, chains;
1570	bool ht_rate;
1571
1572	txinfo = IEEE80211_SKB_CB(skb);
1573	rate = &txinfo->control.rates[0];
1574	ht_rate = !!(txinfo->control.rates[0].flags & IEEE80211_TX_RC_MCS);
1575	carl9170_tx_rate_tpc_chains(ar, txinfo, rate, plcp, &power, &chains);
1576
1577	*ht1 = AR9170_MAC_BCN_HT1_TX_ANT0;
1578	if (chains == AR9170_TX_PHY_TXCHAIN_2)
1579		*ht1 |= AR9170_MAC_BCN_HT1_TX_ANT1;
1580	SET_VAL(AR9170_MAC_BCN_HT1_PWR_CTRL, *ht1, 7);
1581	SET_VAL(AR9170_MAC_BCN_HT1_TPC, *ht1, power);
1582	SET_VAL(AR9170_MAC_BCN_HT1_CHAIN_MASK, *ht1, chains);
1583
1584	if (ht_rate) {
1585		*ht1 |= AR9170_MAC_BCN_HT1_HT_EN;
1586		if (rate->flags & IEEE80211_TX_RC_SHORT_GI)
1587			*plcp |= AR9170_MAC_BCN_HT2_SGI;
1588
1589		if (rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
1590			*ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_SHARED;
1591			*plcp |= AR9170_MAC_BCN_HT2_BW40;
1592		} else if (rate->flags & IEEE80211_TX_RC_DUP_DATA) {
1593			*ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_DUP;
1594			*plcp |= AR9170_MAC_BCN_HT2_BW40;
1595		}
1596
1597		SET_VAL(AR9170_MAC_BCN_HT2_LEN, *plcp, skb->len + FCS_LEN);
1598	} else {
1599		if (*plcp <= AR9170_TX_PHY_RATE_CCK_11M)
1600			*plcp |= ((skb->len + FCS_LEN) << (3 + 16)) + 0x0400;
1601		else
1602			*plcp |= ((skb->len + FCS_LEN) << 16) + 0x0010;
1603	}
1604
1605	return ht_rate;
1606}
1607
1608int carl9170_update_beacon(struct ar9170 *ar, const bool submit)
1609{
1610	struct sk_buff *skb = NULL;
1611	struct carl9170_vif_info *cvif;
1612	__le32 *data, *old = NULL;
1613	u32 word, ht1, plcp, off, addr, len;
1614	int i = 0, err = 0;
1615	bool ht_rate;
1616
1617	rcu_read_lock();
1618	cvif = carl9170_pick_beaconing_vif(ar);
1619	if (!cvif)
1620		goto out_unlock;
1621
1622	skb = ieee80211_beacon_get_tim(ar->hw, carl9170_get_vif(cvif),
1623		NULL, NULL);
1624
1625	if (!skb) {
1626		err = -ENOMEM;
1627		goto err_free;
1628	}
1629
1630	spin_lock_bh(&ar->beacon_lock);
1631	data = (__le32 *)skb->data;
1632	if (cvif->beacon)
1633		old = (__le32 *)cvif->beacon->data;
1634
1635	off = cvif->id * AR9170_MAC_BCN_LENGTH_MAX;
1636	addr = ar->fw.beacon_addr + off;
1637	len = roundup(skb->len + FCS_LEN, 4);
1638
1639	if ((off + len) > ar->fw.beacon_max_len) {
1640		if (net_ratelimit()) {
1641			wiphy_err(ar->hw->wiphy, "beacon does not "
1642				  "fit into device memory!\n");
1643		}
1644		err = -EINVAL;
1645		goto err_unlock;
1646	}
1647
1648	if (len > AR9170_MAC_BCN_LENGTH_MAX) {
1649		if (net_ratelimit()) {
1650			wiphy_err(ar->hw->wiphy, "no support for beacons "
1651				"bigger than %d (yours:%d).\n",
1652				 AR9170_MAC_BCN_LENGTH_MAX, len);
1653		}
1654
1655		err = -EMSGSIZE;
1656		goto err_unlock;
1657	}
1658
1659	ht_rate = carl9170_tx_beacon_physet(ar, skb, &ht1, &plcp);
1660
1661	carl9170_async_regwrite_begin(ar);
1662	carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT1, ht1);
1663	if (ht_rate)
1664		carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT2, plcp);
1665	else
1666		carl9170_async_regwrite(AR9170_MAC_REG_BCN_PLCP, plcp);
1667
1668	for (i = 0; i < DIV_ROUND_UP(skb->len, 4); i++) {
1669		/*
1670		 * XXX: This accesses beyond skb data for up
1671		 *	to the last 3 bytes!!
1672		 */
1673
1674		if (old && (data[i] == old[i]))
1675			continue;
1676
1677		word = le32_to_cpu(data[i]);
1678		carl9170_async_regwrite(addr + 4 * i, word);
1679	}
1680	carl9170_async_regwrite_finish();
1681
1682	dev_kfree_skb_any(cvif->beacon);
1683	cvif->beacon = NULL;
1684
1685	err = carl9170_async_regwrite_result();
1686	if (!err)
1687		cvif->beacon = skb;
1688	spin_unlock_bh(&ar->beacon_lock);
1689	if (err)
1690		goto err_free;
1691
1692	if (submit) {
1693		err = carl9170_bcn_ctrl(ar, cvif->id,
1694					CARL9170_BCN_CTRL_CAB_TRIGGER,
1695					addr, skb->len + FCS_LEN);
1696
1697		if (err)
1698			goto err_free;
1699	}
1700out_unlock:
1701	rcu_read_unlock();
1702	return 0;
1703
1704err_unlock:
1705	spin_unlock_bh(&ar->beacon_lock);
1706
1707err_free:
1708	rcu_read_unlock();
1709	dev_kfree_skb_any(skb);
1710	return err;
1711}
1712