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	/*
 279	 * This does not call ieee80211_tx_info_clear_status() because
 280	 * carl9170_tx_fill_rateinfo() has filled the rate information
 281	 * before we get to this point.
 282	 */
 283	memset_after(&txinfo->status, 0, rates);
 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 = ieee80211_get_tid(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		break;
 844
 845	default:
 846		break;
 847	}
 848
 849	return false;
 850}
 851
 852static bool carl9170_tx_cts_check(struct ar9170 *ar,
 853				  struct ieee80211_tx_rate *rate)
 854{
 855	switch (ar->erp_mode) {
 856	case CARL9170_ERP_AUTO:
 857	case CARL9170_ERP_MAC80211:
 858		if (!(rate->flags & IEEE80211_TX_RC_USE_CTS_PROTECT))
 859			break;
 860		fallthrough;
 861
 862	case CARL9170_ERP_CTS:
 863		return true;
 864
 865	default:
 866		break;
 867	}
 868
 869	return false;
 870}
 871
 872static void carl9170_tx_get_rates(struct ar9170 *ar,
 873				  struct ieee80211_vif *vif,
 874				  struct ieee80211_sta *sta,
 875				  struct sk_buff *skb)
 876{
 877	struct ieee80211_tx_info *info;
 878
 879	BUILD_BUG_ON(IEEE80211_TX_MAX_RATES < CARL9170_TX_MAX_RATES);
 880	BUILD_BUG_ON(IEEE80211_TX_MAX_RATES > IEEE80211_TX_RATE_TABLE_SIZE);
 881
 882	info = IEEE80211_SKB_CB(skb);
 883
 884	ieee80211_get_tx_rates(vif, sta, skb,
 885			       info->control.rates,
 886			       IEEE80211_TX_MAX_RATES);
 887}
 888
 889static void carl9170_tx_apply_rateset(struct ar9170 *ar,
 890				      struct ieee80211_tx_info *sinfo,
 891				      struct sk_buff *skb)
 892{
 893	struct ieee80211_tx_rate *txrate;
 894	struct ieee80211_tx_info *info;
 895	struct _carl9170_tx_superframe *txc = (void *) skb->data;
 896	int i;
 897	bool ampdu;
 898	bool no_ack;
 899
 900	info = IEEE80211_SKB_CB(skb);
 901	ampdu = !!(info->flags & IEEE80211_TX_CTL_AMPDU);
 902	no_ack = !!(info->flags & IEEE80211_TX_CTL_NO_ACK);
 903
 904	/* Set the rate control probe flag for all (sub-) frames.
 905	 * This is because the TX_STATS_AMPDU flag is only set on
 906	 * the last frame, so it has to be inherited.
 907	 */
 908	info->flags |= (sinfo->flags & IEEE80211_TX_CTL_RATE_CTRL_PROBE);
 909
 910	/* NOTE: For the first rate, the ERP & AMPDU flags are directly
 911	 * taken from mac_control. For all fallback rate, the firmware
 912	 * updates the mac_control flags from the rate info field.
 913	 */
 914	for (i = 0; i < CARL9170_TX_MAX_RATES; i++) {
 915		__le32 phy_set;
 916
 917		txrate = &sinfo->control.rates[i];
 918		if (txrate->idx < 0)
 919			break;
 920
 921		phy_set = carl9170_tx_physet(ar, info, txrate);
 922		if (i == 0) {
 923			__le16 mac_tmp = cpu_to_le16(0);
 924
 925			/* first rate - part of the hw's frame header */
 926			txc->f.phy_control = phy_set;
 927
 928			if (ampdu && txrate->flags & IEEE80211_TX_RC_MCS)
 929				mac_tmp |= cpu_to_le16(AR9170_TX_MAC_AGGR);
 930
 931			if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
 932				mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_RTS);
 933			else if (carl9170_tx_cts_check(ar, txrate))
 934				mac_tmp |= cpu_to_le16(AR9170_TX_MAC_PROT_CTS);
 935
 936			txc->f.mac_control |= mac_tmp;
 937		} else {
 938			/* fallback rates are stored in the firmware's
 939			 * retry rate set array.
 940			 */
 941			txc->s.rr[i - 1] = phy_set;
 942		}
 943
 944		SET_VAL(CARL9170_TX_SUPER_RI_TRIES, txc->s.ri[i],
 945			txrate->count);
 946
 947		if (carl9170_tx_rts_check(ar, txrate, ampdu, no_ack))
 948			txc->s.ri[i] |= (AR9170_TX_MAC_PROT_RTS <<
 949				CARL9170_TX_SUPER_RI_ERP_PROT_S);
 950		else if (carl9170_tx_cts_check(ar, txrate))
 951			txc->s.ri[i] |= (AR9170_TX_MAC_PROT_CTS <<
 952				CARL9170_TX_SUPER_RI_ERP_PROT_S);
 953
 954		if (ampdu && (txrate->flags & IEEE80211_TX_RC_MCS))
 955			txc->s.ri[i] |= CARL9170_TX_SUPER_RI_AMPDU;
 956	}
 957}
 958
 959static int carl9170_tx_prepare(struct ar9170 *ar,
 960			       struct ieee80211_sta *sta,
 961			       struct sk_buff *skb)
 962{
 963	struct ieee80211_hdr *hdr;
 964	struct _carl9170_tx_superframe *txc;
 965	struct carl9170_vif_info *cvif;
 966	struct ieee80211_tx_info *info;
 967	struct carl9170_tx_info *arinfo;
 968	unsigned int hw_queue;
 969	__le16 mac_tmp;
 970	u16 len;
 971
 972	BUILD_BUG_ON(sizeof(*arinfo) > sizeof(info->rate_driver_data));
 973	BUILD_BUG_ON(sizeof(struct _carl9170_tx_superdesc) !=
 974		     CARL9170_TX_SUPERDESC_LEN);
 975
 976	BUILD_BUG_ON(sizeof(struct _ar9170_tx_hwdesc) !=
 977		     AR9170_TX_HWDESC_LEN);
 978
 979	BUILD_BUG_ON(AR9170_MAX_VIRTUAL_MAC >
 980		((CARL9170_TX_SUPER_MISC_VIF_ID >>
 981		 CARL9170_TX_SUPER_MISC_VIF_ID_S) + 1));
 982
 983	hw_queue = ar9170_qmap(carl9170_get_queue(ar, skb));
 984
 985	hdr = (void *)skb->data;
 986	info = IEEE80211_SKB_CB(skb);
 987	len = skb->len;
 988
 989	/*
 990	 * Note: If the frame was sent through a monitor interface,
 991	 * the ieee80211_vif pointer can be NULL.
 992	 */
 993	if (likely(info->control.vif))
 994		cvif = (void *) info->control.vif->drv_priv;
 995	else
 996		cvif = NULL;
 997
 998	txc = skb_push(skb, sizeof(*txc));
 999	memset(txc, 0, sizeof(*txc));
1000
1001	SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, txc->s.misc, hw_queue);
1002
1003	if (likely(cvif))
1004		SET_VAL(CARL9170_TX_SUPER_MISC_VIF_ID, txc->s.misc, cvif->id);
1005
1006	if (unlikely(info->flags & IEEE80211_TX_CTL_SEND_AFTER_DTIM))
1007		txc->s.misc |= CARL9170_TX_SUPER_MISC_CAB;
1008
1009	if (unlikely(info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ))
1010		txc->s.misc |= CARL9170_TX_SUPER_MISC_ASSIGN_SEQ;
1011
1012	if (unlikely(ieee80211_is_probe_resp(hdr->frame_control)))
1013		txc->s.misc |= CARL9170_TX_SUPER_MISC_FILL_IN_TSF;
1014
1015	mac_tmp = cpu_to_le16(AR9170_TX_MAC_HW_DURATION |
1016			      AR9170_TX_MAC_BACKOFF);
1017	mac_tmp |= cpu_to_le16((hw_queue << AR9170_TX_MAC_QOS_S) &
1018			       AR9170_TX_MAC_QOS);
1019
1020	if (unlikely(info->flags & IEEE80211_TX_CTL_NO_ACK))
1021		mac_tmp |= cpu_to_le16(AR9170_TX_MAC_NO_ACK);
1022
1023	if (info->control.hw_key) {
1024		len += info->control.hw_key->icv_len;
1025
1026		switch (info->control.hw_key->cipher) {
1027		case WLAN_CIPHER_SUITE_WEP40:
1028		case WLAN_CIPHER_SUITE_WEP104:
1029		case WLAN_CIPHER_SUITE_TKIP:
1030			mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_RC4);
1031			break;
1032		case WLAN_CIPHER_SUITE_CCMP:
1033			mac_tmp |= cpu_to_le16(AR9170_TX_MAC_ENCR_AES);
1034			break;
1035		default:
1036			WARN_ON(1);
1037			goto err_out;
1038		}
1039	}
1040
1041	if (info->flags & IEEE80211_TX_CTL_AMPDU) {
1042		unsigned int density, factor;
1043
1044		if (unlikely(!sta || !cvif))
1045			goto err_out;
1046
1047		factor = min_t(unsigned int, 1u,
1048			       sta->deflink.ht_cap.ampdu_factor);
1049		density = sta->deflink.ht_cap.ampdu_density;
1050
1051		if (density) {
1052			/*
1053			 * Watch out!
1054			 *
1055			 * Otus uses slightly different density values than
1056			 * those from the 802.11n spec.
1057			 */
1058
1059			density = max_t(unsigned int, density + 1, 7u);
1060		}
1061
1062		SET_VAL(CARL9170_TX_SUPER_AMPDU_DENSITY,
1063			txc->s.ampdu_settings, density);
1064
1065		SET_VAL(CARL9170_TX_SUPER_AMPDU_FACTOR,
1066			txc->s.ampdu_settings, factor);
1067	}
1068
1069	txc->s.len = cpu_to_le16(skb->len);
1070	txc->f.length = cpu_to_le16(len + FCS_LEN);
1071	txc->f.mac_control = mac_tmp;
1072
1073	arinfo = (void *)info->rate_driver_data;
1074	arinfo->timeout = jiffies;
1075	arinfo->ar = ar;
1076	kref_init(&arinfo->ref);
1077	return 0;
1078
1079err_out:
1080	skb_pull(skb, sizeof(*txc));
1081	return -EINVAL;
1082}
1083
1084static void carl9170_set_immba(struct ar9170 *ar, struct sk_buff *skb)
1085{
1086	struct _carl9170_tx_superframe *super;
1087
1088	super = (void *) skb->data;
1089	super->f.mac_control |= cpu_to_le16(AR9170_TX_MAC_IMM_BA);
1090}
1091
1092static void carl9170_set_ampdu_params(struct ar9170 *ar, struct sk_buff *skb)
1093{
1094	struct _carl9170_tx_superframe *super;
1095	int tmp;
1096
1097	super = (void *) skb->data;
1098
1099	tmp = (super->s.ampdu_settings & CARL9170_TX_SUPER_AMPDU_DENSITY) <<
1100		CARL9170_TX_SUPER_AMPDU_DENSITY_S;
1101
1102	/*
1103	 * If you haven't noticed carl9170_tx_prepare has already filled
1104	 * in all ampdu spacing & factor parameters.
1105	 * Now it's the time to check whenever the settings have to be
1106	 * updated by the firmware, or if everything is still the same.
1107	 *
1108	 * There's no sane way to handle different density values with
1109	 * this hardware, so we may as well just do the compare in the
1110	 * driver.
1111	 */
1112
1113	if (tmp != ar->current_density) {
1114		ar->current_density = tmp;
1115		super->s.ampdu_settings |=
1116			CARL9170_TX_SUPER_AMPDU_COMMIT_DENSITY;
1117	}
1118
1119	tmp = (super->s.ampdu_settings & CARL9170_TX_SUPER_AMPDU_FACTOR) <<
1120		CARL9170_TX_SUPER_AMPDU_FACTOR_S;
1121
1122	if (tmp != ar->current_factor) {
1123		ar->current_factor = tmp;
1124		super->s.ampdu_settings |=
1125			CARL9170_TX_SUPER_AMPDU_COMMIT_FACTOR;
1126	}
1127}
1128
1129static void carl9170_tx_ampdu(struct ar9170 *ar)
1130{
1131	struct sk_buff_head agg;
1132	struct carl9170_sta_tid *tid_info;
1133	struct sk_buff *skb, *first;
1134	struct ieee80211_tx_info *tx_info_first;
1135	unsigned int i = 0, done_ampdus = 0;
1136	u16 seq, queue, tmpssn;
1137
1138	atomic_inc(&ar->tx_ampdu_scheduler);
1139	ar->tx_ampdu_schedule = false;
1140
1141	if (atomic_read(&ar->tx_ampdu_upload))
1142		return;
1143
1144	if (!ar->tx_ampdu_list_len)
1145		return;
1146
1147	__skb_queue_head_init(&agg);
1148
1149	rcu_read_lock();
1150	tid_info = rcu_dereference(ar->tx_ampdu_iter);
1151	if (WARN_ON_ONCE(!tid_info)) {
1152		rcu_read_unlock();
1153		return;
1154	}
1155
1156retry:
1157	list_for_each_entry_continue_rcu(tid_info, &ar->tx_ampdu_list, list) {
1158		i++;
1159
1160		if (tid_info->state < CARL9170_TID_STATE_PROGRESS)
1161			continue;
1162
1163		queue = TID_TO_WME_AC(tid_info->tid);
1164
1165		spin_lock_bh(&tid_info->lock);
1166		if (tid_info->state != CARL9170_TID_STATE_XMIT)
1167			goto processed;
1168
1169		tid_info->counter++;
1170		first = skb_peek(&tid_info->queue);
1171		tmpssn = carl9170_get_seq(first);
1172		seq = tid_info->snx;
1173
1174		if (unlikely(tmpssn != seq)) {
1175			tid_info->state = CARL9170_TID_STATE_IDLE;
1176
1177			goto processed;
1178		}
1179
1180		tx_info_first = NULL;
1181		while ((skb = skb_peek(&tid_info->queue))) {
1182			/* strict 0, 1, ..., n - 1, n frame sequence order */
1183			if (unlikely(carl9170_get_seq(skb) != seq))
1184				break;
1185
1186			/* don't upload more than AMPDU FACTOR allows. */
1187			if (unlikely(SEQ_DIFF(tid_info->snx, tid_info->bsn) >=
1188			    (tid_info->max - 1)))
1189				break;
1190
1191			if (!tx_info_first) {
1192				carl9170_tx_get_rates(ar, tid_info->vif,
1193						      tid_info->sta, first);
1194				tx_info_first = IEEE80211_SKB_CB(first);
1195			}
1196
1197			carl9170_tx_apply_rateset(ar, tx_info_first, skb);
1198
1199			atomic_inc(&ar->tx_ampdu_upload);
1200			tid_info->snx = seq = SEQ_NEXT(seq);
1201			__skb_unlink(skb, &tid_info->queue);
1202
1203			__skb_queue_tail(&agg, skb);
1204
1205			if (skb_queue_len(&agg) >= CARL9170_NUM_TX_AGG_MAX)
1206				break;
1207		}
1208
1209		if (skb_queue_empty(&tid_info->queue) ||
1210		    carl9170_get_seq(skb_peek(&tid_info->queue)) !=
1211		    tid_info->snx) {
1212			/* stop TID, if A-MPDU frames are still missing,
1213			 * or whenever the queue is empty.
1214			 */
1215
1216			tid_info->state = CARL9170_TID_STATE_IDLE;
1217		}
1218		done_ampdus++;
1219
1220processed:
1221		spin_unlock_bh(&tid_info->lock);
1222
1223		if (skb_queue_empty(&agg))
1224			continue;
1225
1226		/* apply ampdu spacing & factor settings */
1227		carl9170_set_ampdu_params(ar, skb_peek(&agg));
1228
1229		/* set aggregation push bit */
1230		carl9170_set_immba(ar, skb_peek_tail(&agg));
1231
1232		spin_lock_bh(&ar->tx_pending[queue].lock);
1233		skb_queue_splice_tail_init(&agg, &ar->tx_pending[queue]);
1234		spin_unlock_bh(&ar->tx_pending[queue].lock);
1235		ar->tx_schedule = true;
1236	}
1237	if ((done_ampdus++ == 0) && (i++ == 0))
1238		goto retry;
1239
1240	rcu_assign_pointer(ar->tx_ampdu_iter, tid_info);
1241	rcu_read_unlock();
1242}
1243
1244static struct sk_buff *carl9170_tx_pick_skb(struct ar9170 *ar,
1245					    struct sk_buff_head *queue)
1246{
1247	struct sk_buff *skb;
1248	struct ieee80211_tx_info *info;
1249	struct carl9170_tx_info *arinfo;
1250
1251	BUILD_BUG_ON(sizeof(*arinfo) > sizeof(info->rate_driver_data));
1252
1253	spin_lock_bh(&queue->lock);
1254	skb = skb_peek(queue);
1255	if (unlikely(!skb))
1256		goto err_unlock;
1257
1258	if (carl9170_alloc_dev_space(ar, skb))
1259		goto err_unlock;
1260
1261	__skb_unlink(skb, queue);
1262	spin_unlock_bh(&queue->lock);
1263
1264	info = IEEE80211_SKB_CB(skb);
1265	arinfo = (void *) info->rate_driver_data;
1266
1267	arinfo->timeout = jiffies;
1268	return skb;
1269
1270err_unlock:
1271	spin_unlock_bh(&queue->lock);
1272	return NULL;
1273}
1274
1275void carl9170_tx_drop(struct ar9170 *ar, struct sk_buff *skb)
1276{
1277	struct _carl9170_tx_superframe *super;
1278	uint8_t q = 0;
1279
1280	ar->tx_dropped++;
1281
1282	super = (void *)skb->data;
1283	SET_VAL(CARL9170_TX_SUPER_MISC_QUEUE, q,
1284		ar9170_qmap(carl9170_get_queue(ar, skb)));
1285	__carl9170_tx_process_status(ar, super->s.cookie, q);
1286}
1287
1288static bool carl9170_tx_ps_drop(struct ar9170 *ar, struct sk_buff *skb)
1289{
1290	struct ieee80211_sta *sta;
1291	struct carl9170_sta_info *sta_info;
1292	struct ieee80211_tx_info *tx_info;
1293
1294	rcu_read_lock();
1295	sta = __carl9170_get_tx_sta(ar, skb);
1296	if (!sta)
1297		goto out_rcu;
1298
1299	sta_info = (void *) sta->drv_priv;
1300	tx_info = IEEE80211_SKB_CB(skb);
1301
1302	if (unlikely(sta_info->sleeping) &&
1303	    !(tx_info->flags & (IEEE80211_TX_CTL_NO_PS_BUFFER |
1304				IEEE80211_TX_CTL_CLEAR_PS_FILT))) {
1305		rcu_read_unlock();
1306
1307		if (tx_info->flags & IEEE80211_TX_CTL_AMPDU)
1308			atomic_dec(&ar->tx_ampdu_upload);
1309
1310		tx_info->flags |= IEEE80211_TX_STAT_TX_FILTERED;
1311		carl9170_release_dev_space(ar, skb);
1312		carl9170_tx_status(ar, skb, false);
1313		return true;
1314	}
1315
1316out_rcu:
1317	rcu_read_unlock();
1318	return false;
1319}
1320
1321static void carl9170_bar_check(struct ar9170 *ar, struct sk_buff *skb)
1322{
1323	struct _carl9170_tx_superframe *super = (void *) skb->data;
1324	struct ieee80211_bar *bar = (void *) super->frame_data;
1325
1326	if (unlikely(ieee80211_is_back_req(bar->frame_control)) &&
1327	    skb->len >= sizeof(struct ieee80211_bar)) {
1328		struct carl9170_bar_list_entry *entry;
1329		unsigned int queue = skb_get_queue_mapping(skb);
1330
1331		entry = kmalloc(sizeof(*entry), GFP_ATOMIC);
1332		if (!WARN_ON_ONCE(!entry)) {
1333			entry->skb = skb;
1334			spin_lock_bh(&ar->bar_list_lock[queue]);
1335			list_add_tail_rcu(&entry->list, &ar->bar_list[queue]);
1336			spin_unlock_bh(&ar->bar_list_lock[queue]);
1337		}
1338	}
1339}
1340
1341static void carl9170_tx(struct ar9170 *ar)
1342{
1343	struct sk_buff *skb;
1344	unsigned int i, q;
1345	bool schedule_garbagecollector = false;
1346
1347	ar->tx_schedule = false;
1348
1349	if (unlikely(!IS_STARTED(ar)))
1350		return;
1351
1352	carl9170_usb_handle_tx_err(ar);
1353
1354	for (i = 0; i < ar->hw->queues; i++) {
1355		while (!skb_queue_empty(&ar->tx_pending[i])) {
1356			skb = carl9170_tx_pick_skb(ar, &ar->tx_pending[i]);
1357			if (unlikely(!skb))
1358				break;
1359
1360			if (unlikely(carl9170_tx_ps_drop(ar, skb)))
1361				continue;
1362
1363			carl9170_bar_check(ar, skb);
1364
1365			atomic_inc(&ar->tx_total_pending);
1366
1367			q = __carl9170_get_queue(ar, i);
1368			/*
1369			 * NB: tx_status[i] vs. tx_status[q],
1370			 * TODO: Move into pick_skb or alloc_dev_space.
1371			 */
1372			skb_queue_tail(&ar->tx_status[q], skb);
1373
1374			/*
1375			 * increase ref count to "2".
1376			 * Ref counting is the easiest way to solve the
1377			 * race between the urb's completion routine:
1378			 *	carl9170_tx_callback
1379			 * and wlan tx status functions:
1380			 *	carl9170_tx_status/janitor.
1381			 */
1382			carl9170_tx_get_skb(skb);
1383
1384			carl9170_usb_tx(ar, skb);
1385			schedule_garbagecollector = true;
1386		}
1387	}
1388
1389	if (!schedule_garbagecollector)
1390		return;
1391
1392	ieee80211_queue_delayed_work(ar->hw, &ar->tx_janitor,
1393		msecs_to_jiffies(CARL9170_TX_TIMEOUT));
1394}
1395
1396static bool carl9170_tx_ampdu_queue(struct ar9170 *ar,
1397	struct ieee80211_sta *sta, struct sk_buff *skb,
1398	struct ieee80211_tx_info *txinfo)
1399{
1400	struct carl9170_sta_info *sta_info;
1401	struct carl9170_sta_tid *agg;
1402	struct sk_buff *iter;
1403	u16 tid, seq, qseq, off;
1404	bool run = false;
1405
1406	tid = carl9170_get_tid(skb);
1407	seq = carl9170_get_seq(skb);
1408	sta_info = (void *) sta->drv_priv;
1409
1410	rcu_read_lock();
1411	agg = rcu_dereference(sta_info->agg[tid]);
1412
1413	if (!agg)
1414		goto err_unlock_rcu;
1415
1416	spin_lock_bh(&agg->lock);
1417	if (unlikely(agg->state < CARL9170_TID_STATE_IDLE))
1418		goto err_unlock;
1419
1420	/* check if sequence is within the BA window */
1421	if (unlikely(!BAW_WITHIN(agg->bsn, CARL9170_BAW_BITS, seq)))
1422		goto err_unlock;
1423
1424	if (WARN_ON_ONCE(!BAW_WITHIN(agg->snx, CARL9170_BAW_BITS, seq)))
1425		goto err_unlock;
1426
1427	off = SEQ_DIFF(seq, agg->bsn);
1428	if (WARN_ON_ONCE(test_and_set_bit(off, agg->bitmap)))
1429		goto err_unlock;
1430
1431	if (likely(BAW_WITHIN(agg->hsn, CARL9170_BAW_BITS, seq))) {
1432		__skb_queue_tail(&agg->queue, skb);
1433		agg->hsn = seq;
1434		goto queued;
1435	}
1436
1437	skb_queue_reverse_walk(&agg->queue, iter) {
1438		qseq = carl9170_get_seq(iter);
1439
1440		if (BAW_WITHIN(qseq, CARL9170_BAW_BITS, seq)) {
1441			__skb_queue_after(&agg->queue, iter, skb);
1442			goto queued;
1443		}
1444	}
1445
1446	__skb_queue_head(&agg->queue, skb);
1447queued:
1448
1449	if (unlikely(agg->state != CARL9170_TID_STATE_XMIT)) {
1450		if (agg->snx == carl9170_get_seq(skb_peek(&agg->queue))) {
1451			agg->state = CARL9170_TID_STATE_XMIT;
1452			run = true;
1453		}
1454	}
1455
1456	spin_unlock_bh(&agg->lock);
1457	rcu_read_unlock();
1458
1459	return run;
1460
1461err_unlock:
1462	spin_unlock_bh(&agg->lock);
1463
1464err_unlock_rcu:
1465	rcu_read_unlock();
1466	txinfo->flags &= ~IEEE80211_TX_CTL_AMPDU;
1467	carl9170_tx_status(ar, skb, false);
1468	ar->tx_dropped++;
1469	return false;
1470}
1471
1472void carl9170_op_tx(struct ieee80211_hw *hw,
1473		    struct ieee80211_tx_control *control,
1474		    struct sk_buff *skb)
1475{
1476	struct ar9170 *ar = hw->priv;
1477	struct ieee80211_tx_info *info;
1478	struct ieee80211_sta *sta = control->sta;
1479	struct ieee80211_vif *vif;
1480	bool run;
1481
1482	if (unlikely(!IS_STARTED(ar)))
1483		goto err_free;
1484
1485	info = IEEE80211_SKB_CB(skb);
1486	vif = info->control.vif;
1487
1488	if (unlikely(carl9170_tx_prepare(ar, sta, skb)))
1489		goto err_free;
1490
1491	carl9170_tx_accounting(ar, skb);
1492	/*
1493	 * from now on, one has to use carl9170_tx_status to free
1494	 * all ressouces which are associated with the frame.
1495	 */
1496
1497	if (sta) {
1498		struct carl9170_sta_info *stai = (void *) sta->drv_priv;
1499		atomic_inc(&stai->pending_frames);
1500	}
1501
1502	if (info->flags & IEEE80211_TX_CTL_AMPDU) {
1503		/* to static code analyzers and reviewers:
1504		 * mac80211 guarantees that a valid "sta"
1505		 * reference is present, if a frame is to
1506		 * be part of an ampdu. Hence any extra
1507		 * sta == NULL checks are redundant in this
1508		 * special case.
1509		 */
1510		run = carl9170_tx_ampdu_queue(ar, sta, skb, info);
1511		if (run)
1512			carl9170_tx_ampdu(ar);
1513
1514	} else {
1515		unsigned int queue = skb_get_queue_mapping(skb);
1516
1517		carl9170_tx_get_rates(ar, vif, sta, skb);
1518		carl9170_tx_apply_rateset(ar, info, skb);
1519		skb_queue_tail(&ar->tx_pending[queue], skb);
1520	}
1521
1522	carl9170_tx(ar);
1523	return;
1524
1525err_free:
1526	ar->tx_dropped++;
1527	ieee80211_free_txskb(ar->hw, skb);
1528}
1529
1530void carl9170_tx_scheduler(struct ar9170 *ar)
1531{
1532
1533	if (ar->tx_ampdu_schedule)
1534		carl9170_tx_ampdu(ar);
1535
1536	if (ar->tx_schedule)
1537		carl9170_tx(ar);
1538}
1539
1540/* caller has to take rcu_read_lock */
1541static struct carl9170_vif_info *carl9170_pick_beaconing_vif(struct ar9170 *ar)
1542{
1543	struct carl9170_vif_info *cvif;
1544	int i = 1;
1545
1546	/* The AR9170 hardware has no fancy beacon queue or some
1547	 * other scheduling mechanism. So, the driver has to make
1548	 * due by setting the two beacon timers (pretbtt and tbtt)
1549	 * once and then swapping the beacon address in the HW's
1550	 * register file each time the pretbtt fires.
1551	 */
1552
1553	cvif = rcu_dereference(ar->beacon_iter);
1554	if (ar->vifs > 0 && cvif) {
1555		do {
1556			list_for_each_entry_continue_rcu(cvif, &ar->vif_list,
1557							 list) {
1558				if (cvif->active && cvif->enable_beacon)
1559					goto out;
1560			}
1561		} while (ar->beacon_enabled && i--);
1562
1563		/* no entry found in list */
1564		return NULL;
1565	}
1566
1567out:
1568	RCU_INIT_POINTER(ar->beacon_iter, cvif);
1569	return cvif;
1570}
1571
1572static bool carl9170_tx_beacon_physet(struct ar9170 *ar, struct sk_buff *skb,
1573				      u32 *ht1, u32 *plcp)
1574{
1575	struct ieee80211_tx_info *txinfo;
1576	struct ieee80211_tx_rate *rate;
1577	unsigned int power, chains;
1578	bool ht_rate;
1579
1580	txinfo = IEEE80211_SKB_CB(skb);
1581	rate = &txinfo->control.rates[0];
1582	ht_rate = !!(txinfo->control.rates[0].flags & IEEE80211_TX_RC_MCS);
1583	carl9170_tx_rate_tpc_chains(ar, txinfo, rate, plcp, &power, &chains);
1584
1585	*ht1 = AR9170_MAC_BCN_HT1_TX_ANT0;
1586	if (chains == AR9170_TX_PHY_TXCHAIN_2)
1587		*ht1 |= AR9170_MAC_BCN_HT1_TX_ANT1;
1588	SET_VAL(AR9170_MAC_BCN_HT1_PWR_CTRL, *ht1, 7);
1589	SET_VAL(AR9170_MAC_BCN_HT1_TPC, *ht1, power);
1590	SET_VAL(AR9170_MAC_BCN_HT1_CHAIN_MASK, *ht1, chains);
1591
1592	if (ht_rate) {
1593		*ht1 |= AR9170_MAC_BCN_HT1_HT_EN;
1594		if (rate->flags & IEEE80211_TX_RC_SHORT_GI)
1595			*plcp |= AR9170_MAC_BCN_HT2_SGI;
1596
1597		if (rate->flags & IEEE80211_TX_RC_40_MHZ_WIDTH) {
1598			*ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_SHARED;
1599			*plcp |= AR9170_MAC_BCN_HT2_BW40;
1600		} else if (rate->flags & IEEE80211_TX_RC_DUP_DATA) {
1601			*ht1 |= AR9170_MAC_BCN_HT1_BWC_40M_DUP;
1602			*plcp |= AR9170_MAC_BCN_HT2_BW40;
1603		}
1604
1605		SET_VAL(AR9170_MAC_BCN_HT2_LEN, *plcp, skb->len + FCS_LEN);
1606	} else {
1607		if (*plcp <= AR9170_TX_PHY_RATE_CCK_11M)
1608			*plcp |= ((skb->len + FCS_LEN) << (3 + 16)) + 0x0400;
1609		else
1610			*plcp |= ((skb->len + FCS_LEN) << 16) + 0x0010;
1611	}
1612
1613	return ht_rate;
1614}
1615
1616int carl9170_update_beacon(struct ar9170 *ar, const bool submit)
1617{
1618	struct sk_buff *skb = NULL;
1619	struct carl9170_vif_info *cvif;
1620	__le32 *data, *old = NULL;
1621	u32 word, ht1, plcp, off, addr, len;
1622	int i = 0, err = 0;
1623	bool ht_rate;
1624
1625	rcu_read_lock();
1626	cvif = carl9170_pick_beaconing_vif(ar);
1627	if (!cvif)
1628		goto out_unlock;
1629
1630	skb = ieee80211_beacon_get_tim(ar->hw, carl9170_get_vif(cvif),
1631				       NULL, NULL, 0);
1632
1633	if (!skb) {
1634		err = -ENOMEM;
1635		goto err_free;
1636	}
1637
1638	spin_lock_bh(&ar->beacon_lock);
1639	data = (__le32 *)skb->data;
1640	if (cvif->beacon)
1641		old = (__le32 *)cvif->beacon->data;
1642
1643	off = cvif->id * AR9170_MAC_BCN_LENGTH_MAX;
1644	addr = ar->fw.beacon_addr + off;
1645	len = roundup(skb->len + FCS_LEN, 4);
1646
1647	if ((off + len) > ar->fw.beacon_max_len) {
1648		if (net_ratelimit()) {
1649			wiphy_err(ar->hw->wiphy, "beacon does not "
1650				  "fit into device memory!\n");
1651		}
1652		err = -EINVAL;
1653		goto err_unlock;
1654	}
1655
1656	if (len > AR9170_MAC_BCN_LENGTH_MAX) {
1657		if (net_ratelimit()) {
1658			wiphy_err(ar->hw->wiphy, "no support for beacons "
1659				"bigger than %d (yours:%d).\n",
1660				 AR9170_MAC_BCN_LENGTH_MAX, len);
1661		}
1662
1663		err = -EMSGSIZE;
1664		goto err_unlock;
1665	}
1666
1667	ht_rate = carl9170_tx_beacon_physet(ar, skb, &ht1, &plcp);
1668
1669	carl9170_async_regwrite_begin(ar);
1670	carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT1, ht1);
1671	if (ht_rate)
1672		carl9170_async_regwrite(AR9170_MAC_REG_BCN_HT2, plcp);
1673	else
1674		carl9170_async_regwrite(AR9170_MAC_REG_BCN_PLCP, plcp);
1675
1676	for (i = 0; i < DIV_ROUND_UP(skb->len, 4); i++) {
1677		/*
1678		 * XXX: This accesses beyond skb data for up
1679		 *	to the last 3 bytes!!
1680		 */
1681
1682		if (old && (data[i] == old[i]))
1683			continue;
1684
1685		word = le32_to_cpu(data[i]);
1686		carl9170_async_regwrite(addr + 4 * i, word);
1687	}
1688	carl9170_async_regwrite_finish();
1689
1690	dev_kfree_skb_any(cvif->beacon);
1691	cvif->beacon = NULL;
1692
1693	err = carl9170_async_regwrite_result();
1694	if (!err)
1695		cvif->beacon = skb;
1696	spin_unlock_bh(&ar->beacon_lock);
1697	if (err)
1698		goto err_free;
1699
1700	if (submit) {
1701		err = carl9170_bcn_ctrl(ar, cvif->id,
1702					CARL9170_BCN_CTRL_CAB_TRIGGER,
1703					addr, skb->len + FCS_LEN);
1704
1705		if (err)
1706			goto err_free;
1707	}
1708out_unlock:
1709	rcu_read_unlock();
1710	return 0;
1711
1712err_unlock:
1713	spin_unlock_bh(&ar->beacon_lock);
1714
1715err_free:
1716	rcu_read_unlock();
1717	dev_kfree_skb_any(skb);
1718	return err;
1719}