drivers/net/wireless/ath/ath9k/beacon.c

   1 /*
   2  * Copyright (c) 2008-2011 Atheros Communications Inc.
   3  *
   4  * Permission to use, copy, modify, and/or distribute this software for any
   5  * purpose with or without fee is hereby granted, provided that the above
   6  * copyright notice and this permission notice appear in all copies.
   7  *
   8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
   9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  15  */
  16
  17 #include "ath9k.h"
  18
  19 #define FUDGE 2
  20
  21 /*
  22  *  This function will modify certain transmit queue properties depending on
  23  *  the operating mode of the station (AP or AdHoc).  Parameters are AIFS
  24  *  settings and channel width min/max
  25 */
  26 int ath_beaconq_config(struct ath_softc *sc)
  27 {
  28         struct ath_hw *ah = sc->sc_ah;
  29         struct ath_common *common = ath9k_hw_common(ah);
  30         struct ath9k_tx_queue_info qi, qi_be;
  31         struct ath_txq *txq;
  32
  33         ath9k_hw_get_txq_props(ah, sc->beacon.beaconq, &qi);
  34         if (sc->sc_ah->opmode == NL80211_IFTYPE_AP) {
  35                 /* Always burst out beacon and CAB traffic. */
  36                 qi.tqi_aifs = 1;
  37                 qi.tqi_cwmin = 0;
  38                 qi.tqi_cwmax = 0;
  39         } else {
  40                 /* Adhoc mode; important thing is to use 2x cwmin. */
  41                 txq = sc->tx.txq_map[WME_AC_BE];
  42                 ath9k_hw_get_txq_props(ah, txq->axq_qnum, &qi_be);
  43                 qi.tqi_aifs = qi_be.tqi_aifs;
  44                 qi.tqi_cwmin = 4*qi_be.tqi_cwmin;
  45                 qi.tqi_cwmax = qi_be.tqi_cwmax;
  46         }
  47
  48         if (!ath9k_hw_set_txq_props(ah, sc->beacon.beaconq, &qi)) {
  49                 ath_err(common,
  50                         "Unable to update h/w beacon queue parameters\n");
  51                 return 0;
  52         } else {
  53                 ath9k_hw_resettxqueue(ah, sc->beacon.beaconq);
  54                 return 1;
  55         }
  56 }
  57
  58 /*
  59  *  Associates the beacon frame buffer with a transmit descriptor.  Will set
  60  *  up rate codes, and channel flags. Beacons are always sent out at the
  61  *  lowest rate, and are not retried.
  62 */
  63 static void ath_beacon_setup(struct ath_softc *sc, struct ath_vif *avp,
  64                              struct ath_buf *bf, int rateidx)
  65 {
  66         struct sk_buff *skb = bf->bf_mpdu;
  67         struct ath_hw *ah = sc->sc_ah;
  68         struct ath_common *common = ath9k_hw_common(ah);
  69         struct ath_desc *ds;
  70         struct ath9k_11n_rate_series series[4];
  71         int flags, ctsrate = 0, ctsduration = 0;
  72         struct ieee80211_supported_band *sband;
  73         u8 rate = 0;
  74
  75         ds = bf->bf_desc;
  76         flags = ATH9K_TXDESC_NOACK;
  77
  78         ds->ds_link = 0;
  79
  80         sband = &sc->sbands[common->hw->conf.channel->band];
  81         rate = sband->bitrates[rateidx].hw_value;
  82         if (sc->sc_flags & SC_OP_PREAMBLE_SHORT)
  83                 rate |= sband->bitrates[rateidx].hw_value_short;
  84
  85         ath9k_hw_set11n_txdesc(ah, ds, skb->len + FCS_LEN,
  86                                ATH9K_PKT_TYPE_BEACON,
  87                                MAX_RATE_POWER,
  88                                ATH9K_TXKEYIX_INVALID,
  89                                ATH9K_KEY_TYPE_CLEAR,
  90                                flags);
  91
  92         /* NB: beacon's BufLen must be a multiple of 4 bytes */
  93         ath9k_hw_filltxdesc(ah, ds, roundup(skb->len, 4),
  94                             true, true, ds, bf->bf_buf_addr,
  95                             sc->beacon.beaconq);
  96
  97         memset(series, 0, sizeof(struct ath9k_11n_rate_series) * 4);
  98         series[0].Tries = 1;
  99         series[0].Rate = rate;
 100         series[0].ChSel = ath_txchainmask_reduction(sc,
 101                         common->tx_chainmask, series[0].Rate);
 102         series[0].RateFlags = (ctsrate) ? ATH9K_RATESERIES_RTS_CTS : 0;
 103         ath9k_hw_set11n_ratescenario(ah, ds, ds, 0, ctsrate, ctsduration,
 104                                      series, 4, 0);
 105 }
 106
 107 static void ath_tx_cabq(struct ieee80211_hw *hw, struct sk_buff *skb)
 108 {
 109         struct ath_softc *sc = hw->priv;
 110         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 111         struct ath_tx_control txctl;
 112
 113         memset(&txctl, 0, sizeof(struct ath_tx_control));
 114         txctl.txq = sc->beacon.cabq;
 115
 116         ath_dbg(common, ATH_DBG_XMIT,
 117                 "transmitting CABQ packet, skb: %p\n", skb);
 118
 119         if (ath_tx_start(hw, skb, &txctl) != 0) {
 120                 ath_dbg(common, ATH_DBG_XMIT, "CABQ TX failed\n");
 121                 dev_kfree_skb_any(skb);
 122         }
 123 }
 124
 125 static struct ath_buf *ath_beacon_generate(struct ieee80211_hw *hw,
 126                                            struct ieee80211_vif *vif)
 127 {
 128         struct ath_softc *sc = hw->priv;
 129         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 130         struct ath_buf *bf;
 131         struct ath_vif *avp;
 132         struct sk_buff *skb;
 133         struct ath_txq *cabq;
 134         struct ieee80211_tx_info *info;
 135         int cabq_depth;
 136
 137         avp = (void *)vif->drv_priv;
 138         cabq = sc->beacon.cabq;
 139
 140         if ((avp->av_bcbuf == NULL) || !avp->is_bslot_active)
 141                 return NULL;
 142
 143         /* Release the old beacon first */
 144
 145         bf = avp->av_bcbuf;
 146         skb = bf->bf_mpdu;
 147         if (skb) {
 148                 dma_unmap_single(sc->dev, bf->bf_buf_addr,
 149                                  skb->len, DMA_TO_DEVICE);
 150                 dev_kfree_skb_any(skb);
 151                 bf->bf_buf_addr = 0;
 152         }
 153
 154         /* Get a new beacon from mac80211 */
 155
 156         skb = ieee80211_beacon_get(hw, vif);
 157         bf->bf_mpdu = skb;
 158         if (skb == NULL)
 159                 return NULL;
 160         ((struct ieee80211_mgmt *)skb->data)->u.beacon.timestamp =
 161                 avp->tsf_adjust;
 162
 163         info = IEEE80211_SKB_CB(skb);
 164         if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
 165                 /*
 166                  * TODO: make sure the seq# gets assigned properly (vs. other
 167                  * TX frames)
 168                  */
 169                 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
 170                 sc->tx.seq_no += 0x10;
 171                 hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
 172                 hdr->seq_ctrl |= cpu_to_le16(sc->tx.seq_no);
 173         }
 174
 175         bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
 176                                          skb->len, DMA_TO_DEVICE);
 177         if (unlikely(dma_mapping_error(sc->dev, bf->bf_buf_addr))) {
 178                 dev_kfree_skb_any(skb);
 179                 bf->bf_mpdu = NULL;
 180                 bf->bf_buf_addr = 0;
 181                 ath_err(common, "dma_mapping_error on beaconing\n");
 182                 return NULL;
 183         }
 184
 185         skb = ieee80211_get_buffered_bc(hw, vif);
 186
 187         /*
 188          * if the CABQ traffic from previous DTIM is pending and the current
 189          *  beacon is also a DTIM.
 190          *  1) if there is only one vif let the cab traffic continue.
 191          *  2) if there are more than one vif and we are using staggered
 192          *     beacons, then drain the cabq by dropping all the frames in
 193          *     the cabq so that the current vifs cab traffic can be scheduled.
 194          */
 195         spin_lock_bh(&cabq->axq_lock);
 196         cabq_depth = cabq->axq_depth;
 197         spin_unlock_bh(&cabq->axq_lock);
 198
 199         if (skb && cabq_depth) {
 200                 if (sc->nvifs > 1) {
 201                         ath_dbg(common, ATH_DBG_BEACON,
 202                                 "Flushing previous cabq traffic\n");
 203                         ath_draintxq(sc, cabq, false);
 204                 }
 205         }
 206
 207         ath_beacon_setup(sc, avp, bf, info->control.rates[0].idx);
 208
 209         while (skb) {
 210                 ath_tx_cabq(hw, skb);
 211                 skb = ieee80211_get_buffered_bc(hw, vif);
 212         }
 213
 214         return bf;
 215 }
 216
 217 int ath_beacon_alloc(struct ath_softc *sc, struct ieee80211_vif *vif)
 218 {
 219         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 220         struct ath_vif *avp;
 221         struct ath_buf *bf;
 222         struct sk_buff *skb;
 223         struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
 224         __le64 tstamp;
 225
 226         avp = (void *)vif->drv_priv;
 227
 228         /* Allocate a beacon descriptor if we haven't done so. */
 229         if (!avp->av_bcbuf) {
 230                 /* Allocate beacon state for hostap/ibss.  We know
 231                  * a buffer is available. */
 232                 avp->av_bcbuf = list_first_entry(&sc->beacon.bbuf,
 233                                                  struct ath_buf, list);
 234                 list_del(&avp->av_bcbuf->list);
 235
 236                 if (ath9k_uses_beacons(vif->type)) {
 237                         int slot;
 238                         /*
 239                          * Assign the vif to a beacon xmit slot. As
 240                          * above, this cannot fail to find one.
 241                          */
 242                         avp->av_bslot = 0;
 243                         for (slot = 0; slot < ATH_BCBUF; slot++)
 244                                 if (sc->beacon.bslot[slot] == NULL) {
 245                                         avp->av_bslot = slot;
 246                                         avp->is_bslot_active = false;
 247
 248                                         /* NB: keep looking for a double slot */
 249                                         if (slot == 0 || !sc->beacon.bslot[slot-1])
 250                                                 break;
 251                                 }
 252                         BUG_ON(sc->beacon.bslot[avp->av_bslot] != NULL);
 253                         sc->beacon.bslot[avp->av_bslot] = vif;
 254                         sc->nbcnvifs++;
 255                 }
 256         }
 257
 258         /* release the previous beacon frame, if it already exists. */
 259         bf = avp->av_bcbuf;
 260         if (bf->bf_mpdu != NULL) {
 261                 skb = bf->bf_mpdu;
 262                 dma_unmap_single(sc->dev, bf->bf_buf_addr,
 263                                  skb->len, DMA_TO_DEVICE);
 264                 dev_kfree_skb_any(skb);
 265                 bf->bf_mpdu = NULL;
 266                 bf->bf_buf_addr = 0;
 267         }
 268
 269         /* NB: the beacon data buffer must be 32-bit aligned. */
 270         skb = ieee80211_beacon_get(sc->hw, vif);
 271         if (skb == NULL)
 272                 return -ENOMEM;
 273
 274         tstamp = ((struct ieee80211_mgmt *)skb->data)->u.beacon.timestamp;
 275         sc->beacon.bc_tstamp = (u32) le64_to_cpu(tstamp);
 276         /* Calculate a TSF adjustment factor required for staggered beacons. */
 277         if (avp->av_bslot > 0) {
 278                 u64 tsfadjust;
 279                 int intval;
 280
 281                 intval = cur_conf->beacon_interval ? : ATH_DEFAULT_BINTVAL;
 282
 283                 /*
 284                  * Calculate the TSF offset for this beacon slot, i.e., the
 285                  * number of usecs that need to be added to the timestamp field
 286                  * in Beacon and Probe Response frames. Beacon slot 0 is
 287                  * processed at the correct offset, so it does not require TSF
 288                  * adjustment. Other slots are adjusted to get the timestamp
 289                  * close to the TBTT for the BSS.
 290                  */
 291                 tsfadjust = TU_TO_USEC(intval * avp->av_bslot) / ATH_BCBUF;
 292                 avp->tsf_adjust = cpu_to_le64(tsfadjust);
 293
 294                 ath_dbg(common, ATH_DBG_BEACON,
 295                         "stagger beacons, bslot %d intval %u tsfadjust %llu\n",
 296                         avp->av_bslot, intval, (unsigned long long)tsfadjust);
 297
 298                 ((struct ieee80211_mgmt *)skb->data)->u.beacon.timestamp =
 299                         avp->tsf_adjust;
 300         } else
 301                 avp->tsf_adjust = cpu_to_le64(0);
 302
 303         bf->bf_mpdu = skb;
 304         bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
 305                                          skb->len, DMA_TO_DEVICE);
 306         if (unlikely(dma_mapping_error(sc->dev, bf->bf_buf_addr))) {
 307                 dev_kfree_skb_any(skb);
 308                 bf->bf_mpdu = NULL;
 309                 bf->bf_buf_addr = 0;
 310                 ath_err(common, "dma_mapping_error on beacon alloc\n");
 311                 return -ENOMEM;
 312         }
 313         avp->is_bslot_active = true;
 314
 315         return 0;
 316 }
 317
 318 void ath_beacon_return(struct ath_softc *sc, struct ath_vif *avp)
 319 {
 320         if (avp->av_bcbuf != NULL) {
 321                 struct ath_buf *bf;
 322
 323                 avp->is_bslot_active = false;
 324                 if (avp->av_bslot != -1) {
 325                         sc->beacon.bslot[avp->av_bslot] = NULL;
 326                         sc->nbcnvifs--;
 327                         avp->av_bslot = -1;
 328                 }
 329
 330                 bf = avp->av_bcbuf;
 331                 if (bf->bf_mpdu != NULL) {
 332                         struct sk_buff *skb = bf->bf_mpdu;
 333                         dma_unmap_single(sc->dev, bf->bf_buf_addr,
 334                                          skb->len, DMA_TO_DEVICE);
 335                         dev_kfree_skb_any(skb);
 336                         bf->bf_mpdu = NULL;
 337                         bf->bf_buf_addr = 0;
 338                 }
 339                 list_add_tail(&bf->list, &sc->beacon.bbuf);
 340
 341                 avp->av_bcbuf = NULL;
 342         }
 343 }
 344
 345 void ath_beacon_tasklet(unsigned long data)
 346 {
 347         struct ath_softc *sc = (struct ath_softc *)data;
 348         struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
 349         struct ath_hw *ah = sc->sc_ah;
 350         struct ath_common *common = ath9k_hw_common(ah);
 351         struct ath_buf *bf = NULL;
 352         struct ieee80211_vif *vif;
 353         int slot;
 354         u32 bfaddr, bc = 0;
 355
 356         /*
 357          * Check if the previous beacon has gone out.  If
 358          * not don't try to post another, skip this period
 359          * and wait for the next.  Missed beacons indicate
 360          * a problem and should not occur.  If we miss too
 361          * many consecutive beacons reset the device.
 362          */
 363         if (ath9k_hw_numtxpending(ah, sc->beacon.beaconq) != 0) {
 364                 sc->beacon.bmisscnt++;
 365
 366                 if (sc->beacon.bmisscnt < BSTUCK_THRESH * sc->nbcnvifs) {
 367                         ath_dbg(common, ATH_DBG_BSTUCK,
 368                                 "missed %u consecutive beacons\n",
 369                                 sc->beacon.bmisscnt);
 370                         ath9k_hw_stop_dma_queue(ah, sc->beacon.beaconq);
 371                         if (sc->beacon.bmisscnt > 3)
 372                                 ath9k_hw_bstuck_nfcal(ah);
 373                 } else if (sc->beacon.bmisscnt >= BSTUCK_THRESH) {
 374                         ath_dbg(common, ATH_DBG_BSTUCK,
 375                                 "beacon is officially stuck\n");
 376                         sc->sc_flags |= SC_OP_TSF_RESET;
 377                         ath_reset(sc, true);
 378                 }
 379
 380                 return;
 381         }
 382
 383         /*
 384          * Generate beacon frames. we are sending frames
 385          * staggered so calculate the slot for this frame based
 386          * on the tsf to safeguard against missing an swba.
 387          */
 388
 389
 390         if (ah->opmode == NL80211_IFTYPE_AP) {
 391                 u16 intval;
 392                 u32 tsftu;
 393                 u64 tsf;
 394
 395                 intval = cur_conf->beacon_interval ? : ATH_DEFAULT_BINTVAL;
 396                 tsf = ath9k_hw_gettsf64(ah);
 397                 tsf += TU_TO_USEC(ah->config.sw_beacon_response_time);
 398                 tsftu = TSF_TO_TU((tsf * ATH_BCBUF) >>32, tsf * ATH_BCBUF);
 399                 slot = (tsftu % (intval * ATH_BCBUF)) / intval;
 400                 vif = sc->beacon.bslot[slot];
 401
 402                 ath_dbg(common, ATH_DBG_BEACON,
 403                         "slot %d [tsf %llu tsftu %u intval %u] vif %p\n",
 404                         slot, tsf, tsftu / ATH_BCBUF, intval, vif);
 405         } else {
 406                 slot = 0;
 407                 vif = sc->beacon.bslot[slot];
 408         }
 409
 410
 411         bfaddr = 0;
 412         if (vif) {
 413                 bf = ath_beacon_generate(sc->hw, vif);
 414                 if (bf != NULL) {
 415                         bfaddr = bf->bf_daddr;
 416                         bc = 1;
 417                 }
 418
 419                 if (sc->beacon.bmisscnt != 0) {
 420                         ath_dbg(common, ATH_DBG_BSTUCK,
 421                                 "resume beacon xmit after %u misses\n",
 422                                 sc->beacon.bmisscnt);
 423                         sc->beacon.bmisscnt = 0;
 424                 }
 425         }
 426
 427         /*
 428          * Handle slot time change when a non-ERP station joins/leaves
 429          * an 11g network.  The 802.11 layer notifies us via callback,
 430          * we mark updateslot, then wait one beacon before effecting
 431          * the change.  This gives associated stations at least one
 432          * beacon interval to note the state change.
 433          *
 434          * NB: The slot time change state machine is clocked according
 435          *     to whether we are bursting or staggering beacons.  We
 436          *     recognize the request to update and record the current
 437          *     slot then don't transition until that slot is reached
 438          *     again.  If we miss a beacon for that slot then we'll be
 439          *     slow to transition but we'll be sure at least one beacon
 440          *     interval has passed.  When bursting slot is always left
 441          *     set to ATH_BCBUF so this check is a noop.
 442          */
 443         if (sc->beacon.updateslot == UPDATE) {
 444                 sc->beacon.updateslot = COMMIT; /* commit next beacon */
 445                 sc->beacon.slotupdate = slot;
 446         } else if (sc->beacon.updateslot == COMMIT && sc->beacon.slotupdate == slot) {
 447                 ah->slottime = sc->beacon.slottime;
 448                 ath9k_hw_init_global_settings(ah);
 449                 sc->beacon.updateslot = OK;
 450         }
 451         if (bfaddr != 0) {
 452                 /* NB: cabq traffic should already be queued and primed */
 453                 ath9k_hw_puttxbuf(ah, sc->beacon.beaconq, bfaddr);
 454                 ath9k_hw_txstart(ah, sc->beacon.beaconq);
 455
 456                 sc->beacon.ast_be_xmit += bc;     /* XXX per-vif? */
 457         }
 458 }
 459
 460 static void ath9k_beacon_init(struct ath_softc *sc,
 461                               u32 next_beacon,
 462                               u32 beacon_period)
 463 {
 464         if (sc->sc_flags & SC_OP_TSF_RESET) {
 465                 ath9k_ps_wakeup(sc);
 466                 ath9k_hw_reset_tsf(sc->sc_ah);
 467         }
 468
 469         ath9k_hw_beaconinit(sc->sc_ah, next_beacon, beacon_period);
 470
 471         if (sc->sc_flags & SC_OP_TSF_RESET) {
 472                 ath9k_ps_restore(sc);
 473                 sc->sc_flags &= ~SC_OP_TSF_RESET;
 474         }
 475 }
 476
 477 /*
 478  * For multi-bss ap support beacons are either staggered evenly over N slots or
 479  * burst together.  For the former arrange for the SWBA to be delivered for each
 480  * slot. Slots that are not occupied will generate nothing.
 481  */
 482 static void ath_beacon_config_ap(struct ath_softc *sc,
 483                                  struct ath_beacon_config *conf)
 484 {
 485         struct ath_hw *ah = sc->sc_ah;
 486         u32 nexttbtt, intval;
 487
 488         /* NB: the beacon interval is kept internally in TU's */
 489         intval = TU_TO_USEC(conf->beacon_interval & ATH9K_BEACON_PERIOD);
 490         intval /= ATH_BCBUF;    /* for staggered beacons */
 491         nexttbtt = intval;
 492
 493         /*
 494          * In AP mode we enable the beacon timers and SWBA interrupts to
 495          * prepare beacon frames.
 496          */
 497         ah->imask |= ATH9K_INT_SWBA;
 498         ath_beaconq_config(sc);
 499
 500         /* Set the computed AP beacon timers */
 501
 502         ath9k_hw_disable_interrupts(ah);
 503         ath9k_beacon_init(sc, nexttbtt, intval);
 504         sc->beacon.bmisscnt = 0;
 505         ath9k_hw_set_interrupts(ah, ah->imask);
 506 }
 507
 508 /*
 509  * This sets up the beacon timers according to the timestamp of the last
 510  * received beacon and the current TSF, configures PCF and DTIM
 511  * handling, programs the sleep registers so the hardware will wakeup in
 512  * time to receive beacons, and configures the beacon miss handling so
 513  * we'll receive a BMISS interrupt when we stop seeing beacons from the AP
 514  * we've associated with.
 515  */
 516 static void ath_beacon_config_sta(struct ath_softc *sc,
 517                                   struct ath_beacon_config *conf)
 518 {
 519         struct ath_hw *ah = sc->sc_ah;
 520         struct ath_common *common = ath9k_hw_common(ah);
 521         struct ath9k_beacon_state bs;
 522         int dtimperiod, dtimcount, sleepduration;
 523         int cfpperiod, cfpcount;
 524         u32 nexttbtt = 0, intval, tsftu;
 525         u64 tsf;
 526         int num_beacons, offset, dtim_dec_count, cfp_dec_count;
 527
 528         /* No need to configure beacon if we are not associated */
 529         if (!common->curaid) {
 530                 ath_dbg(common, ATH_DBG_BEACON,
 531                         "STA is not yet associated..skipping beacon config\n");
 532                 return;
 533         }
 534
 535         memset(&bs, 0, sizeof(bs));
 536         intval = conf->beacon_interval & ATH9K_BEACON_PERIOD;
 537
 538         /*
 539          * Setup dtim and cfp parameters according to
 540          * last beacon we received (which may be none).
 541          */
 542         dtimperiod = conf->dtim_period;
 543         dtimcount = conf->dtim_count;
 544         if (dtimcount >= dtimperiod)    /* NB: sanity check */
 545                 dtimcount = 0;
 546         cfpperiod = 1;                  /* NB: no PCF support yet */
 547         cfpcount = 0;
 548
 549         sleepduration = conf->listen_interval * intval;
 550
 551         /*
 552          * Pull nexttbtt forward to reflect the current
 553          * TSF and calculate dtim+cfp state for the result.
 554          */
 555         tsf = ath9k_hw_gettsf64(ah);
 556         tsftu = TSF_TO_TU(tsf>>32, tsf) + FUDGE;
 557
 558         num_beacons = tsftu / intval + 1;
 559         offset = tsftu % intval;
 560         nexttbtt = tsftu - offset;
 561         if (offset)
 562                 nexttbtt += intval;
 563
 564         /* DTIM Beacon every dtimperiod Beacon */
 565         dtim_dec_count = num_beacons % dtimperiod;
 566         /* CFP every cfpperiod DTIM Beacon */
 567         cfp_dec_count = (num_beacons / dtimperiod) % cfpperiod;
 568         if (dtim_dec_count)
 569                 cfp_dec_count++;
 570
 571         dtimcount -= dtim_dec_count;
 572         if (dtimcount < 0)
 573                 dtimcount += dtimperiod;
 574
 575         cfpcount -= cfp_dec_count;
 576         if (cfpcount < 0)
 577                 cfpcount += cfpperiod;
 578
 579         bs.bs_intval = intval;
 580         bs.bs_nexttbtt = nexttbtt;
 581         bs.bs_dtimperiod = dtimperiod*intval;
 582         bs.bs_nextdtim = bs.bs_nexttbtt + dtimcount*intval;
 583         bs.bs_cfpperiod = cfpperiod*bs.bs_dtimperiod;
 584         bs.bs_cfpnext = bs.bs_nextdtim + cfpcount*bs.bs_dtimperiod;
 585         bs.bs_cfpmaxduration = 0;
 586
 587         /*
 588          * Calculate the number of consecutive beacons to miss* before taking
 589          * a BMISS interrupt. The configuration is specified in TU so we only
 590          * need calculate based on the beacon interval.  Note that we clamp the
 591          * result to at most 15 beacons.
 592          */
 593         if (sleepduration > intval) {
 594                 bs.bs_bmissthreshold = conf->listen_interval *
 595                         ATH_DEFAULT_BMISS_LIMIT / 2;
 596         } else {
 597                 bs.bs_bmissthreshold = DIV_ROUND_UP(conf->bmiss_timeout, intval);
 598                 if (bs.bs_bmissthreshold > 15)
 599                         bs.bs_bmissthreshold = 15;
 600                 else if (bs.bs_bmissthreshold <= 0)
 601                         bs.bs_bmissthreshold = 1;
 602         }
 603
 604         /*
 605          * Calculate sleep duration. The configuration is given in ms.
 606          * We ensure a multiple of the beacon period is used. Also, if the sleep
 607          * duration is greater than the DTIM period then it makes senses
 608          * to make it a multiple of that.
 609          *
 610          * XXX fixed at 100ms
 611          */
 612
 613         bs.bs_sleepduration = roundup(IEEE80211_MS_TO_TU(100), sleepduration);
 614         if (bs.bs_sleepduration > bs.bs_dtimperiod)
 615                 bs.bs_sleepduration = bs.bs_dtimperiod;
 616
 617         /* TSF out of range threshold fixed at 1 second */
 618         bs.bs_tsfoor_threshold = ATH9K_TSFOOR_THRESHOLD;
 619
 620         ath_dbg(common, ATH_DBG_BEACON, "tsf: %llu tsftu: %u\n", tsf, tsftu);
 621         ath_dbg(common, ATH_DBG_BEACON,
 622                 "bmiss: %u sleep: %u cfp-period: %u maxdur: %u next: %u\n",
 623                 bs.bs_bmissthreshold, bs.bs_sleepduration,
 624                 bs.bs_cfpperiod, bs.bs_cfpmaxduration, bs.bs_cfpnext);
 625
 626         /* Set the computed STA beacon timers */
 627
 628         ath9k_hw_disable_interrupts(ah);
 629         ath9k_hw_set_sta_beacon_timers(ah, &bs);
 630         ah->imask |= ATH9K_INT_BMISS;
 631
 632         /*
 633          * If the beacon config is called beacause of TSFOOR,
 634          * Interrupts will be enabled back at the end of ath9k_tasklet
 635          */
 636         if (!(sc->ps_flags & PS_TSFOOR_SYNC))
 637                 ath9k_hw_set_interrupts(ah, ah->imask);
 638 }
 639
 640 static void ath_beacon_config_adhoc(struct ath_softc *sc,
 641                                     struct ath_beacon_config *conf)
 642 {
 643         struct ath_hw *ah = sc->sc_ah;
 644         struct ath_common *common = ath9k_hw_common(ah);
 645         u32 tsf, delta, intval, nexttbtt;
 646
 647         tsf = ath9k_hw_gettsf32(ah) + TU_TO_USEC(FUDGE);
 648         intval = TU_TO_USEC(conf->beacon_interval & ATH9K_BEACON_PERIOD);
 649
 650         if (!sc->beacon.bc_tstamp)
 651                 nexttbtt = tsf + intval;
 652         else {
 653                 if (tsf > sc->beacon.bc_tstamp)
 654                         delta = (tsf - sc->beacon.bc_tstamp);
 655                 else
 656                         delta = (tsf + 1 + (~0U - sc->beacon.bc_tstamp));
 657                 nexttbtt = tsf + roundup(delta, intval);
 658         }
 659
 660         ath_dbg(common, ATH_DBG_BEACON,
 661                 "IBSS nexttbtt %u intval %u (%u)\n",
 662                 nexttbtt, intval, conf->beacon_interval);
 663
 664         /*
 665          * In IBSS mode enable the beacon timers but only enable SWBA interrupts
 666          * if we need to manually prepare beacon frames.  Otherwise we use a
 667          * self-linked tx descriptor and let the hardware deal with things.
 668          */
 669         ah->imask |= ATH9K_INT_SWBA;
 670
 671         ath_beaconq_config(sc);
 672
 673         /* Set the computed ADHOC beacon timers */
 674
 675         ath9k_hw_disable_interrupts(ah);
 676         ath9k_beacon_init(sc, nexttbtt, intval);
 677         sc->beacon.bmisscnt = 0;
 678         /*
 679          * If the beacon config is called beacause of TSFOOR,
 680          * Interrupts will be enabled back at the end of ath9k_tasklet
 681          */
 682         if (!(sc->ps_flags & PS_TSFOOR_SYNC))
 683                 ath9k_hw_set_interrupts(ah, ah->imask);
 684 }
 685
 686 static bool ath9k_allow_beacon_config(struct ath_softc *sc,
 687                                       struct ieee80211_vif *vif)
 688 {
 689         struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
 690         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 691         struct ieee80211_bss_conf *bss_conf = &vif->bss_conf;
 692         struct ath_vif *avp = (void *)vif->drv_priv;
 693
 694         /*
 695          * Can not have different beacon interval on multiple
 696          * AP interface case
 697          */
 698         if ((sc->sc_ah->opmode == NL80211_IFTYPE_AP) &&
 699             (sc->nbcnvifs > 1) &&
 700             (vif->type == NL80211_IFTYPE_AP) &&
 701             (cur_conf->beacon_interval != bss_conf->beacon_int)) {
 702                 ath_dbg(common, ATH_DBG_CONFIG,
 703                         "Changing beacon interval of multiple \
 704                         AP interfaces !\n");
 705                 return false;
 706         }
 707         /*
 708          * Can not configure station vif's beacon config
 709          * while on AP opmode
 710          */
 711         if ((sc->sc_ah->opmode == NL80211_IFTYPE_AP) &&
 712             (vif->type != NL80211_IFTYPE_AP)) {
 713                 ath_dbg(common, ATH_DBG_CONFIG,
 714                         "STA vif's beacon not allowed on AP mode\n");
 715                 return false;
 716         }
 717         /*
 718          * Do not allow beacon config if HW was already configured
 719          * with another STA vif
 720          */
 721         if ((sc->sc_ah->opmode == NL80211_IFTYPE_STATION) &&
 722             (vif->type == NL80211_IFTYPE_STATION) &&
 723             (sc->sc_flags & SC_OP_BEACONS) &&
 724             !avp->primary_sta_vif) {
 725                 ath_dbg(common, ATH_DBG_CONFIG,
 726                         "Beacon already configured for a station interface\n");
 727                 return false;
 728         }
 729         return true;
 730 }
 731
 732 void ath_beacon_config(struct ath_softc *sc, struct ieee80211_vif *vif)
 733 {
 734         struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
 735         struct ieee80211_bss_conf *bss_conf = &vif->bss_conf;
 736
 737         if (!ath9k_allow_beacon_config(sc, vif))
 738                 return;
 739
 740         /* Setup the beacon configuration parameters */
 741         cur_conf->beacon_interval = bss_conf->beacon_int;
 742         cur_conf->dtim_period = bss_conf->dtim_period;
 743         cur_conf->listen_interval = 1;
 744         cur_conf->dtim_count = 1;
 745         cur_conf->bmiss_timeout =
 746                 ATH_DEFAULT_BMISS_LIMIT * cur_conf->beacon_interval;
 747
 748         /*
 749          * It looks like mac80211 may end up using beacon interval of zero in
 750          * some cases (at least for mesh point). Avoid getting into an
 751          * infinite loop by using a bit safer value instead. To be safe,
 752          * do sanity check on beacon interval for all operating modes.
 753          */
 754         if (cur_conf->beacon_interval == 0)
 755                 cur_conf->beacon_interval = 100;
 756
 757         /*
 758          * We don't parse dtim period from mac80211 during the driver
 759          * initialization as it breaks association with hidden-ssid
 760          * AP and it causes latency in roaming
 761          */
 762         if (cur_conf->dtim_period == 0)
 763                 cur_conf->dtim_period = 1;
 764
 765         ath_set_beacon(sc);
 766 }
 767
 768 static bool ath_has_valid_bslot(struct ath_softc *sc)
 769 {
 770         struct ath_vif *avp;
 771         int slot;
 772         bool found = false;
 773
 774         for (slot = 0; slot < ATH_BCBUF; slot++) {
 775                 if (sc->beacon.bslot[slot]) {
 776                         avp = (void *)sc->beacon.bslot[slot]->drv_priv;
 777                         if (avp->is_bslot_active) {
 778                                 found = true;
 779                                 break;
 780                         }
 781                 }
 782         }
 783         return found;
 784 }
 785
 786
 787 void ath_set_beacon(struct ath_softc *sc)
 788 {
 789         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
 790         struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
 791
 792         switch (sc->sc_ah->opmode) {
 793         case NL80211_IFTYPE_AP:
 794                 if (ath_has_valid_bslot(sc))
 795                         ath_beacon_config_ap(sc, cur_conf);
 796                 break;
 797         case NL80211_IFTYPE_ADHOC:
 798         case NL80211_IFTYPE_MESH_POINT:
 799                 ath_beacon_config_adhoc(sc, cur_conf);
 800                 break;
 801         case NL80211_IFTYPE_STATION:
 802                 ath_beacon_config_sta(sc, cur_conf);
 803                 break;
 804         default:
 805                 ath_dbg(common, ATH_DBG_CONFIG,
 806                         "Unsupported beaconing mode\n");
 807                 return;
 808         }
 809
 810         sc->sc_flags |= SC_OP_BEACONS;
 811 }
 812
 813 void ath9k_set_beaconing_status(struct ath_softc *sc, bool status)
 814 {
 815         struct ath_hw *ah = sc->sc_ah;
 816
 817         if (!ath_has_valid_bslot(sc))
 818                 return;
 819
 820         ath9k_ps_wakeup(sc);
 821         if (status) {
 822                 /* Re-enable beaconing */
 823                 ah->imask |= ATH9K_INT_SWBA;
 824                 ath9k_hw_set_interrupts(ah, ah->imask);
 825         } else {
 826                 /* Disable SWBA interrupt */
 827                 ah->imask &= ~ATH9K_INT_SWBA;
 828                 ath9k_hw_set_interrupts(ah, ah->imask);
 829                 tasklet_kill(&sc->bcon_tasklet);
 830                 ath9k_hw_stop_dma_queue(ah, sc->beacon.beaconq);
 831         }
 832         ath9k_ps_restore(sc);
 833 }