diff options
Diffstat (limited to 'drivers/net/wireless/ath9k/beacon.c')
| -rw-r--r-- | drivers/net/wireless/ath9k/beacon.c | 885 |
1 files changed, 885 insertions, 0 deletions
diff --git a/drivers/net/wireless/ath9k/beacon.c b/drivers/net/wireless/ath9k/beacon.c new file mode 100644 index 0000000..9e15c30 --- /dev/null +++ b/drivers/net/wireless/ath9k/beacon.c @@ -0,0 +1,885 @@ +/* + * Copyright (c) 2008 Atheros Communications Inc. + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES + * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF + * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR + * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES + * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN + * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF + * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. + */ + + /* Implementation of beacon processing. */ + +#include "core.h" + +/* + * Configure parameters for the beacon queue + * + * This function will modify certain transmit queue properties depending on + * the operating mode of the station (AP or AdHoc). Parameters are AIFS + * settings and channel width min/max +*/ +static int ath_beaconq_config(struct ath_softc *sc) +{ + struct ath_hal *ah = sc->sc_ah; + struct ath9k_tx_queue_info qi; + + ath9k_hw_get_txq_props(ah, sc->sc_bhalq, &qi); + if (sc->sc_ah->ah_opmode == ATH9K_M_HOSTAP) { + /* Always burst out beacon and CAB traffic. */ + qi.tqi_aifs = 1; + qi.tqi_cwmin = 0; + qi.tqi_cwmax = 0; + } else { + /* Adhoc mode; important thing is to use 2x cwmin. */ + qi.tqi_aifs = sc->sc_beacon_qi.tqi_aifs; + qi.tqi_cwmin = 2*sc->sc_beacon_qi.tqi_cwmin; + qi.tqi_cwmax = sc->sc_beacon_qi.tqi_cwmax; + } + + if (!ath9k_hw_set_txq_props(ah, sc->sc_bhalq, &qi)) { + DPRINTF(sc, ATH_DBG_FATAL, + "%s: unable to update h/w beacon queue parameters\n", + __func__); + return 0; + } else { + ath9k_hw_resettxqueue(ah, sc->sc_bhalq); /* push to h/w */ + return 1; + } +} + +/* + * Setup the beacon frame for transmit. + * + * Associates the beacon frame buffer with a transmit descriptor. Will set + * up all required antenna switch parameters, rate codes, and channel flags. + * Beacons are always sent out at the lowest rate, and are not retried. +*/ +static void ath_beacon_setup(struct ath_softc *sc, + struct ath_vap *avp, struct ath_buf *bf) +{ + struct sk_buff *skb = (struct sk_buff *)bf->bf_mpdu; + struct ath_hal *ah = sc->sc_ah; + struct ath_desc *ds; + struct ath9k_11n_rate_series series[4]; + const struct ath9k_rate_table *rt; + int flags, antenna; + u8 rix, rate; + int ctsrate = 0; + int ctsduration = 0; + + DPRINTF(sc, ATH_DBG_BEACON, "%s: m %p len %u\n", + __func__, skb, skb->len); + + /* setup descriptors */ + ds = bf->bf_desc; + + flags = ATH9K_TXDESC_NOACK; + + if (sc->sc_ah->ah_opmode == ATH9K_M_IBSS && + (ah->ah_caps.hw_caps & ATH9K_HW_CAP_VEOL)) { + ds->ds_link = bf->bf_daddr; /* self-linked */ + flags |= ATH9K_TXDESC_VEOL; + /* Let hardware handle antenna switching. */ + antenna = 0; + } else { + ds->ds_link = 0; + /* + * Switch antenna every beacon. + * Should only switch every beacon period, not for every + * SWBA's + * XXX assumes two antenna + */ + antenna = ((sc->ast_be_xmit / sc->sc_nbcnvaps) & 1 ? 2 : 1); + } + + ds->ds_data = bf->bf_buf_addr; + + /* + * Calculate rate code. + * XXX everything at min xmit rate + */ + rix = 0; + rt = sc->sc_currates; + rate = rt->info[rix].rateCode; + if (sc->sc_flags & SC_OP_PREAMBLE_SHORT) + rate |= rt->info[rix].shortPreamble; + + ath9k_hw_set11n_txdesc(ah, ds, + skb->len + FCS_LEN, /* frame length */ + ATH9K_PKT_TYPE_BEACON, /* Atheros packet type */ + avp->av_btxctl.txpower, /* txpower XXX */ + ATH9K_TXKEYIX_INVALID, /* no encryption */ + ATH9K_KEY_TYPE_CLEAR, /* no encryption */ + flags /* no ack, + veol for beacons */ + ); + + /* NB: beacon's BufLen must be a multiple of 4 bytes */ + ath9k_hw_filltxdesc(ah, ds, + roundup(skb->len, 4), /* buffer length */ + true, /* first segment */ + true, /* last segment */ + ds /* first descriptor */ + ); + + memset(series, 0, sizeof(struct ath9k_11n_rate_series) * 4); + series[0].Tries = 1; + series[0].Rate = rate; + series[0].ChSel = sc->sc_tx_chainmask; + series[0].RateFlags = (ctsrate) ? ATH9K_RATESERIES_RTS_CTS : 0; + ath9k_hw_set11n_ratescenario(ah, ds, ds, 0, + ctsrate, ctsduration, series, 4, 0); +} + +/* + * Generate beacon frame and queue cab data for a vap. + * + * Updates the contents of the beacon frame. It is assumed that the buffer for + * the beacon frame has been allocated in the ATH object, and simply needs to + * be filled for this cycle. Also, any CAB (crap after beacon?) traffic will + * be added to the beacon frame at this point. +*/ +static struct ath_buf *ath_beacon_generate(struct ath_softc *sc, int if_id) +{ + struct ath_buf *bf; + struct ath_vap *avp; + struct sk_buff *skb; + struct ath_txq *cabq; + struct ieee80211_tx_info *info; + int cabq_depth; + + avp = sc->sc_vaps[if_id]; + ASSERT(avp); + + cabq = sc->sc_cabq; + + if (avp->av_bcbuf == NULL) { + DPRINTF(sc, ATH_DBG_BEACON, "%s: avp=%p av_bcbuf=%p\n", + __func__, avp, avp->av_bcbuf); + return NULL; + } + + bf = avp->av_bcbuf; + skb = (struct sk_buff *)bf->bf_mpdu; + if (skb) { + pci_unmap_single(sc->pdev, bf->bf_dmacontext, + skb_end_pointer(skb) - skb->head, + PCI_DMA_TODEVICE); + } + + skb = ieee80211_beacon_get(sc->hw, avp->av_if_data); + bf->bf_mpdu = skb; + if (skb == NULL) + return NULL; + + info = IEEE80211_SKB_CB(skb); + if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) { + /* + * TODO: make sure the seq# gets assigned properly (vs. other + * TX frames) + */ + struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data; + sc->seq_no += 0x10; + hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG); + hdr->seq_ctrl |= cpu_to_le16(sc->seq_no); + } + + bf->bf_buf_addr = bf->bf_dmacontext = + pci_map_single(sc->pdev, skb->data, + skb_end_pointer(skb) - skb->head, + PCI_DMA_TODEVICE); + + skb = ieee80211_get_buffered_bc(sc->hw, avp->av_if_data); + + /* + * if the CABQ traffic from previous DTIM is pending and the current + * beacon is also a DTIM. + * 1) if there is only one vap let the cab traffic continue. + * 2) if there are more than one vap and we are using staggered + * beacons, then drain the cabq by dropping all the frames in + * the cabq so that the current vaps cab traffic can be scheduled. + */ + spin_lock_bh(&cabq->axq_lock); + cabq_depth = cabq->axq_depth; + spin_unlock_bh(&cabq->axq_lock); + + if (skb && cabq_depth) { + /* + * Unlock the cabq lock as ath_tx_draintxq acquires + * the lock again which is a common function and that + * acquires txq lock inside. + */ + if (sc->sc_nvaps > 1) { + ath_tx_draintxq(sc, cabq, false); + DPRINTF(sc, ATH_DBG_BEACON, + "%s: flush previous cabq traffic\n", __func__); + } + } + + /* Construct tx descriptor. */ + ath_beacon_setup(sc, avp, bf); + + /* + * Enable the CAB queue before the beacon queue to + * insure cab frames are triggered by this beacon. + */ + while (skb) { + ath_tx_cabq(sc, skb); + skb = ieee80211_get_buffered_bc(sc->hw, avp->av_if_data); + } + + return bf; +} + +/* + * Startup beacon transmission for adhoc mode when they are sent entirely + * by the hardware using the self-linked descriptor + veol trick. +*/ +static void ath_beacon_start_adhoc(struct ath_softc *sc, int if_id) +{ + struct ath_hal *ah = sc->sc_ah; + struct ath_buf *bf; + struct ath_vap *avp; + struct sk_buff *skb; + + avp = sc->sc_vaps[if_id]; + ASSERT(avp); + + if (avp->av_bcbuf == NULL) { + DPRINTF(sc, ATH_DBG_BEACON, "%s: avp=%p av_bcbuf=%p\n", + __func__, avp, avp != NULL ? avp->av_bcbuf : NULL); + return; + } + bf = avp->av_bcbuf; + skb = (struct sk_buff *) bf->bf_mpdu; + + /* Construct tx descriptor. */ + ath_beacon_setup(sc, avp, bf); + + /* NB: caller is known to have already stopped tx dma */ + ath9k_hw_puttxbuf(ah, sc->sc_bhalq, bf->bf_daddr); + ath9k_hw_txstart(ah, sc->sc_bhalq); + DPRINTF(sc, ATH_DBG_BEACON, "%s: TXDP%u = %llx (%p)\n", __func__, + sc->sc_bhalq, ito64(bf->bf_daddr), bf->bf_desc); +} + +/* + * Setup a h/w transmit queue for beacons. + * + * This function allocates an information structure (struct ath9k_txq_info) + * on the stack, sets some specific parameters (zero out channel width + * min/max, and enable aifs). The info structure does not need to be + * persistant. +*/ +int ath_beaconq_setup(struct ath_hal *ah) +{ + struct ath9k_tx_queue_info qi; + + memset(&qi, 0, sizeof(qi)); + qi.tqi_aifs = 1; + qi.tqi_cwmin = 0; + qi.tqi_cwmax = 0; + /* NB: don't enable any interrupts */ + return ath9k_hw_setuptxqueue(ah, ATH9K_TX_QUEUE_BEACON, &qi); +} + + +/* + * Allocate and setup an initial beacon frame. + * + * Allocate a beacon state variable for a specific VAP instance created on + * the ATH interface. This routine also calculates the beacon "slot" for + * staggared beacons in the mBSSID case. +*/ +int ath_beacon_alloc(struct ath_softc *sc, int if_id) +{ + struct ath_vap *avp; + struct ieee80211_hdr *hdr; + struct ath_buf *bf; + struct sk_buff *skb; + __le64 tstamp; + + avp = sc->sc_vaps[if_id]; + ASSERT(avp); + + /* Allocate a beacon descriptor if we haven't done so. */ + if (!avp->av_bcbuf) { + /* Allocate beacon state for hostap/ibss. We know + * a buffer is available. */ + + avp->av_bcbuf = list_first_entry(&sc->sc_bbuf, + struct ath_buf, list); + list_del(&avp->av_bcbuf->list); + + if (sc->sc_ah->ah_opmode == ATH9K_M_HOSTAP || + !(sc->sc_ah->ah_caps.hw_caps & ATH9K_HW_CAP_VEOL)) { + int slot; + /* + * Assign the vap to a beacon xmit slot. As + * above, this cannot fail to find one. + */ + avp->av_bslot = 0; + for (slot = 0; slot < ATH_BCBUF; slot++) + if (sc->sc_bslot[slot] == ATH_IF_ID_ANY) { + /* + * XXX hack, space out slots to better + * deal with misses + */ + if (slot+1 < ATH_BCBUF && + sc->sc_bslot[slot+1] == + ATH_IF_ID_ANY) { + avp->av_bslot = slot+1; + break; + } + avp->av_bslot = slot; + /* NB: keep looking for a double slot */ + } + BUG_ON(sc->sc_bslot[avp->av_bslot] != ATH_IF_ID_ANY); + sc->sc_bslot[avp->av_bslot] = if_id; + sc->sc_nbcnvaps++; + } + } + + /* release the previous beacon frame , if it already exists. */ + bf = avp->av_bcbuf; + if (bf->bf_mpdu != NULL) { + skb = (struct sk_buff *)bf->bf_mpdu; + pci_unmap_single(sc->pdev, bf->bf_dmacontext, + skb_end_pointer(skb) - skb->head, + PCI_DMA_TODEVICE); + dev_kfree_skb_any(skb); + bf->bf_mpdu = NULL; + } + + /* + * NB: the beacon data buffer must be 32-bit aligned. + * FIXME: Fill avp->av_btxctl.txpower and + * avp->av_btxctl.shortPreamble + */ + skb = ieee80211_beacon_get(sc->hw, avp->av_if_data); + if (skb == NULL) { + DPRINTF(sc, ATH_DBG_BEACON, "%s: cannot get skb\n", + __func__); + return -ENOMEM; + } + + tstamp = ((struct ieee80211_mgmt *)skb->data)->u.beacon.timestamp; + sc->bc_tstamp = le64_to_cpu(tstamp); + + /* + * Calculate a TSF adjustment factor required for + * staggered beacons. Note that we assume the format + * of the beacon frame leaves the tstamp field immediately + * following the header. + */ + if (avp->av_bslot > 0) { + u64 tsfadjust; + __le64 val; + int intval; + + intval = sc->hw->conf.beacon_int ? + sc->hw->conf.beacon_int : ATH_DEFAULT_BINTVAL; + + /* + * The beacon interval is in TU's; the TSF in usecs. + * We figure out how many TU's to add to align the + * timestamp then convert to TSF units and handle + * byte swapping before writing it in the frame. + * The hardware will then add this each time a beacon + * frame is sent. Note that we align vap's 1..N + * and leave vap 0 untouched. This means vap 0 + * has a timestamp in one beacon interval while the + * others get a timestamp aligned to the next interval. + */ + tsfadjust = (intval * (ATH_BCBUF - avp->av_bslot)) / ATH_BCBUF; + val = cpu_to_le64(tsfadjust << 10); /* TU->TSF */ + + DPRINTF(sc, ATH_DBG_BEACON, + "%s: %s beacons, bslot %d intval %u tsfadjust %llu\n", + __func__, "stagger", + avp->av_bslot, intval, (unsigned long long)tsfadjust); + + hdr = (struct ieee80211_hdr *)skb->data; + memcpy(&hdr[1], &val, sizeof(val)); + } + + bf->bf_buf_addr = bf->bf_dmacontext = + pci_map_single(sc->pdev, skb->data, + skb_end_pointer(skb) - skb->head, + PCI_DMA_TODEVICE); + bf->bf_mpdu = skb; + + return 0; +} + +/* + * Reclaim beacon resources and return buffer to the pool. + * + * Checks the VAP to put the beacon frame buffer back to the ATH object + * queue, and de-allocates any skbs that were sent as CAB traffic. +*/ +void ath_beacon_return(struct ath_softc *sc, struct ath_vap *avp) +{ + if (avp->av_bcbuf != NULL) { + struct ath_buf *bf; + + if (avp->av_bslot != -1) { + sc->sc_bslot[avp->av_bslot] = ATH_IF_ID_ANY; + sc->sc_nbcnvaps--; + } + + bf = avp->av_bcbuf; + if (bf->bf_mpdu != NULL) { + struct sk_buff *skb = (struct sk_buff *)bf->bf_mpdu; + pci_unmap_single(sc->pdev, bf->bf_dmacontext, + skb_end_pointer(skb) - skb->head, + PCI_DMA_TODEVICE); + dev_kfree_skb_any(skb); + bf->bf_mpdu = NULL; + } + list_add_tail(&bf->list, &sc->sc_bbuf); + + avp->av_bcbuf = NULL; + } +} + +/* + * Tasklet for Sending Beacons + * + * Transmit one or more beacon frames at SWBA. Dynamic updates to the frame + * contents are done as needed and the slot time is also adjusted based on + * current state. +*/ +void ath9k_beacon_tasklet(unsigned long data) +{ + struct ath_softc *sc = (struct ath_softc *)data; + struct ath_hal *ah = sc->sc_ah; + struct ath_buf *bf = NULL; + int slot, if_id; + u32 bfaddr; + u32 rx_clear = 0, rx_frame = 0, tx_frame = 0; + u32 show_cycles = 0; + u32 bc = 0; /* beacon count */ + u64 tsf; + u32 tsftu; + u16 intval; + + if (sc->sc_flags & SC_OP_NO_RESET) { + show_cycles = ath9k_hw_GetMibCycleCountsPct(ah, + &rx_clear, + &rx_frame, + &tx_frame); + } + + /* + * Check if the previous beacon has gone out. If + * not don't try to post another, skip this period + * and wait for the next. Missed beacons indicate + * a problem and should not occur. If we miss too + * many consecutive beacons reset the device. + * + * FIXME: Clean up this mess !! + */ + if (ath9k_hw_numtxpending(ah, sc->sc_bhalq) != 0) { + sc->sc_bmisscount++; + /* XXX: doth needs the chanchange IE countdown decremented. + * We should consider adding a mac80211 call to indicate + * a beacon miss so appropriate action could be taken + * (in that layer). + */ + if (sc->sc_bmisscount < BSTUCK_THRESH) { + if (sc->sc_flags & SC_OP_NO_RESET) { + DPRINTF(sc, ATH_DBG_BEACON, + "%s: missed %u consecutive beacons\n", + __func__, sc->sc_bmisscount); + if (show_cycles) { + /* + * Display cycle counter stats from HW + * to aide in debug of stickiness. + */ + DPRINTF(sc, ATH_DBG_BEACON, + "%s: busy times: rx_clear=%d, " + "rx_frame=%d, tx_frame=%d\n", + __func__, rx_clear, rx_frame, + tx_frame); + } else { + DPRINTF(sc, ATH_DBG_BEACON, + "%s: unable to obtain " + "busy times\n", __func__); + } + } else { + DPRINTF(sc, ATH_DBG_BEACON, + "%s: missed %u consecutive beacons\n", + __func__, sc->sc_bmisscount); + } + } else if (sc->sc_bmisscount >= BSTUCK_THRESH) { + if (sc->sc_flags & SC_OP_NO_RESET) { + if (sc->sc_bmisscount == BSTUCK_THRESH) { + DPRINTF(sc, ATH_DBG_BEACON, + "%s: beacon is officially " + "stuck\n", __func__); + ath9k_hw_dmaRegDump(ah); + } + } else { + DPRINTF(sc, ATH_DBG_BEACON, + "%s: beacon is officially stuck\n", + __func__); + ath_bstuck_process(sc); + } + } + return; + } + + if (sc->sc_bmisscount != 0) { + if (sc->sc_flags & SC_OP_NO_RESET) { + DPRINTF(sc, ATH_DBG_BEACON, + "%s: resume beacon xmit after %u misses\n", + __func__, sc->sc_bmisscount); + } else { + DPRINTF(sc, ATH_DBG_BEACON, + "%s: resume beacon xmit after %u misses\n", + __func__, sc->sc_bmisscount); + } + sc->sc_bmisscount = 0; + } + + /* + * Generate beacon frames. we are sending frames + * staggered so calculate the slot for this frame based + * on the tsf to safeguard against missing an swba. + */ + + intval = sc->hw->conf.beacon_int ? + sc->hw->conf.beacon_int : ATH_DEFAULT_BINTVAL; + + tsf = ath9k_hw_gettsf64(ah); + tsftu = TSF_TO_TU(tsf>>32, tsf); + slot = ((tsftu % intval) * ATH_BCBUF) / intval; + if_id = sc->sc_bslot[(slot + 1) % ATH_BCBUF]; + + DPRINTF(sc, ATH_DBG_BEACON, + "%s: slot %d [tsf %llu tsftu %u intval %u] if_id %d\n", + __func__, slot, (unsigned long long)tsf, tsftu, + intval, if_id); + + bfaddr = 0; + if (if_id != ATH_IF_ID_ANY) { + bf = ath_beacon_generate(sc, if_id); + if (bf != NULL) { + bfaddr = bf->bf_daddr; + bc = 1; + } + } + /* + * Handle slot time change when a non-ERP station joins/leaves + * an 11g network. The 802.11 layer notifies us via callback, + * we mark updateslot, then wait one beacon before effecting + * the change. This gives associated stations at least one + * beacon interval to note the state change. + * + * NB: The slot time change state machine is clocked according + * to whether we are bursting or staggering beacons. We + * recognize the request to update and record the current + * slot then don't transition until that slot is reached + * again. If we miss a beacon for that slot then we'll be + * slow to transition but we'll be sure at least one beacon + * interval has passed. When bursting slot is always left + * set to ATH_BCBUF so this check is a noop. + */ + /* XXX locking */ + if (sc->sc_updateslot == UPDATE) { + sc->sc_updateslot = COMMIT; /* commit next beacon */ + sc->sc_slotupdate = slot; + } else if (sc->sc_updateslot == COMMIT && sc->sc_slotupdate == slot) + ath_setslottime(sc); /* commit change to hardware */ + + if (bfaddr != 0) { + /* + * Stop any current dma and put the new frame(s) on the queue. + * This should never fail since we check above that no frames + * are still pending on the queue. + */ + if (!ath9k_hw_stoptxdma(ah, sc->sc_bhalq)) { + DPRINTF(sc, ATH_DBG_FATAL, + "%s: beacon queue %u did not stop?\n", + __func__, sc->sc_bhalq); + /* NB: the HAL still stops DMA, so proceed */ + } + + /* NB: cabq traffic should already be queued and primed */ + ath9k_hw_puttxbuf(ah, sc->sc_bhalq, bfaddr); + ath9k_hw_txstart(ah, sc->sc_bhalq); + + sc->ast_be_xmit += bc; /* XXX per-vap? */ + } +} + +/* + * Tasklet for Beacon Stuck processing + * + * Processing for Beacon Stuck. + * Basically resets the chip. +*/ +void ath_bstuck_process(struct ath_softc *sc) +{ + DPRINTF(sc, ATH_DBG_BEACON, + "%s: stuck beacon; resetting (bmiss count %u)\n", + __func__, sc->sc_bmisscount); + ath_reset(sc, false); +} + +/* + * Configure the beacon and sleep timers. + * + * When operating as an AP this resets the TSF and sets + * up the hardware to notify us when we need to issue beacons. + * + * When operating in station mode this sets up the beacon + * timers according to the timestamp of the last received + * beacon and the current TSF, configures PCF and DTIM + * handling, programs the sleep registers so the hardware + * will wakeup in time to receive beacons, and configures + * the beacon miss handling so we'll receive a BMISS + * interrupt when we stop seeing beacons from the AP + * we've associated with. + */ +void ath_beacon_config(struct ath_softc *sc, int if_id) +{ + struct ath_hal *ah = sc->sc_ah; + struct ath_beacon_config conf; + enum ath9k_opmode av_opmode; + u32 nexttbtt, intval; + + if (if_id != ATH_IF_ID_ANY) + av_opmode = sc->sc_vaps[if_id]->av_opmode; + else + av_opmode = sc->sc_ah->ah_opmode; + + memset(&conf, 0, sizeof(struct ath_beacon_config)); + + conf.beacon_interval = sc->hw->conf.beacon_int ? + sc->hw->conf.beacon_int : ATH_DEFAULT_BINTVAL; + conf.listen_interval = 1; + conf.dtim_period = conf.beacon_interval; + conf.dtim_count = 1; + conf.bmiss_timeout = ATH_DEFAULT_BMISS_LIMIT * conf.beacon_interval; + + /* extract tstamp from last beacon and convert to TU */ + nexttbtt = TSF_TO_TU(sc->bc_tstamp >> 32, sc->bc_tstamp); + + /* XXX conditionalize multi-bss support? */ + if (sc->sc_ah->ah_opmode == ATH9K_M_HOSTAP) { + /* + * For multi-bss ap support beacons are either staggered + * evenly over N slots or burst together. For the former + * arrange for the SWBA to be delivered for each slot. + * Slots that are not occupied will generate nothing. + */ + /* NB: the beacon interval is kept internally in TU's */ + intval = conf.beacon_interval & ATH9K_BEACON_PERIOD; + intval /= ATH_BCBUF; /* for staggered beacons */ + } else { + intval = conf.beacon_interval & ATH9K_BEACON_PERIOD; + } + + if (nexttbtt == 0) /* e.g. for ap mode */ + nexttbtt = intval; + else if (intval) /* NB: can be 0 for monitor mode */ + nexttbtt = roundup(nexttbtt, intval); + + DPRINTF(sc, ATH_DBG_BEACON, "%s: nexttbtt %u intval %u (%u)\n", + __func__, nexttbtt, intval, conf.beacon_interval); + + /* Check for ATH9K_M_HOSTAP and sc_nostabeacons for WDS client */ + if (sc->sc_ah->ah_opmode == ATH9K_M_STA) { + struct ath9k_beacon_state bs; + u64 tsf; + u32 tsftu; + int dtimperiod, dtimcount, sleepduration; + int cfpperiod, cfpcount; + + /* + * Setup dtim and cfp parameters according to + * last beacon we received (which may be none). + */ + dtimperiod = conf.dtim_period; + if (dtimperiod <= 0) /* NB: 0 if not known */ + dtimperiod = 1; + dtimcount = conf.dtim_count; + if (dtimcount >= dtimperiod) /* NB: sanity check */ + dtimcount = 0; + cfpperiod = 1; /* NB: no PCF support yet */ + cfpcount = 0; + + sleepduration = conf.listen_interval * intval; + if (sleepduration <= 0) + sleepduration = intval; + +#define FUDGE 2 + /* + * Pull nexttbtt forward to reflect the current + * TSF and calculate dtim+cfp state for the result. + */ + tsf = ath9k_hw_gettsf64(ah); + tsftu = TSF_TO_TU(tsf>>32, tsf) + FUDGE; + do { + nexttbtt += intval; + if (--dtimcount < 0) { + dtimcount = dtimperiod - 1; + if (--cfpcount < 0) + cfpcount = cfpperiod - 1; + } + } while (nexttbtt < tsftu); +#undef FUDGE + memset(&bs, 0, sizeof(bs)); + bs.bs_intval = intval; + bs.bs_nexttbtt = nexttbtt; + bs.bs_dtimperiod = dtimperiod*intval; + bs.bs_nextdtim = bs.bs_nexttbtt + dtimcount*intval; + bs.bs_cfpperiod = cfpperiod*bs.bs_dtimperiod; + bs.bs_cfpnext = bs.bs_nextdtim + cfpcount*bs.bs_dtimperiod; + bs.bs_cfpmaxduration = 0; + + /* + * Calculate the number of consecutive beacons to miss + * before taking a BMISS interrupt. The configuration + * is specified in TU so we only need calculate based + * on the beacon interval. Note that we clamp the + * result to at most 15 beacons. + */ + if (sleepduration > intval) { + bs.bs_bmissthreshold = conf.listen_interval * + ATH_DEFAULT_BMISS_LIMIT / 2; + } else { + bs.bs_bmissthreshold = + DIV_ROUND_UP(conf.bmiss_timeout, intval); + if (bs.bs_bmissthreshold > 15) + bs.bs_bmissthreshold = 15; + else if (bs.bs_bmissthreshold <= 0) + bs.bs_bmissthreshold = 1; + } + + /* + * Calculate sleep duration. The configuration is + * given in ms. We insure a multiple of the beacon + * period is used. Also, if the sleep duration is + * greater than the DTIM period then it makes senses + * to make it a multiple of that. + * + * XXX fixed at 100ms + */ + + bs.bs_sleepduration = roundup(IEEE80211_MS_TO_TU(100), + sleepduration); + if (bs.bs_sleepduration > bs.bs_dtimperiod) + bs.bs_sleepduration = bs.bs_dtimperiod; + + DPRINTF(sc, ATH_DBG_BEACON, + "%s: tsf %llu " + "tsf:tu %u " + "intval %u " + "nexttbtt %u " + "dtim %u " + "nextdtim %u " + "bmiss %u " + "sleep %u " + "cfp:period %u " + "maxdur %u " + "next %u " + "timoffset %u\n", + __func__, + (unsigned long long)tsf, tsftu, + bs.bs_intval, + bs.bs_nexttbtt, + bs.bs_dtimperiod, + bs.bs_nextdtim, + bs.bs_bmissthreshold, + bs.bs_sleepduration, + bs.bs_cfpperiod, + bs.bs_cfpmaxduration, + bs.bs_cfpnext, + bs.bs_timoffset + ); + + ath9k_hw_set_interrupts(ah, 0); + ath9k_hw_set_sta_beacon_timers(ah, &bs); + sc->sc_imask |= ATH9K_INT_BMISS; + ath9k_hw_set_interrupts(ah, sc->sc_imask); + } else { + u64 tsf; + u32 tsftu; + ath9k_hw_set_interrupts(ah, 0); + if (nexttbtt == intval) + intval |= ATH9K_BEACON_RESET_TSF; + if (sc->sc_ah->ah_opmode == ATH9K_M_IBSS) { + /* + * Pull nexttbtt forward to reflect the current + * TSF + */ +#define FUDGE 2 + if (!(intval & ATH9K_BEACON_RESET_TSF)) { + tsf = ath9k_hw_gettsf64(ah); + tsftu = TSF_TO_TU((u32)(tsf>>32), + (u32)tsf) + FUDGE; + do { + nexttbtt += intval; + } while (nexttbtt < tsftu); + } +#undef FUDGE + DPRINTF(sc, ATH_DBG_BEACON, + "%s: IBSS nexttbtt %u intval %u (%u)\n", + __func__, nexttbtt, + intval & ~ATH9K_BEACON_RESET_TSF, + conf.beacon_interval); + + /* + * In IBSS mode enable the beacon timers but only + * enable SWBA interrupts if we need to manually + * prepare beacon frames. Otherwise we use a + * self-linked tx descriptor and let the hardware + * deal with things. + */ + intval |= ATH9K_BEACON_ENA; + if (!(ah->ah_caps.hw_caps & ATH9K_HW_CAP_VEOL)) + sc->sc_imask |= ATH9K_INT_SWBA; + ath_beaconq_config(sc); + } else if (sc->sc_ah->ah_opmode == ATH9K_M_HOSTAP) { + /* + * In AP mode we enable the beacon timers and + * SWBA interrupts to prepare beacon frames. + */ + intval |= ATH9K_BEACON_ENA; + sc->sc_imask |= ATH9K_INT_SWBA; /* beacon prepare */ + ath_beaconq_config(sc); + } + ath9k_hw_beaconinit(ah, nexttbtt, intval); + sc->sc_bmisscount = 0; + ath9k_hw_set_interrupts(ah, sc->sc_imask); + /* + * When using a self-linked beacon descriptor in + * ibss mode load it once here. + */ + if (sc->sc_ah->ah_opmode == ATH9K_M_IBSS && + (ah->ah_caps.hw_caps & ATH9K_HW_CAP_VEOL)) + ath_beacon_start_adhoc(sc, 0); + } +} + +/* Function to collect beacon rssi data and resync beacon if necessary */ + +void ath_beacon_sync(struct ath_softc *sc, int if_id) +{ + /* + * Resync beacon timers using the tsf of the + * beacon frame we just received. + */ + ath_beacon_config(sc, if_id); + sc->sc_flags |= SC_OP_BEACONS; +} |
