2 * Copyright (c) 2008-2009 Atheros Communications Inc.
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.
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.
19 static struct ieee80211_hw * ath_get_virt_hw(struct ath_softc *sc,
20 struct ieee80211_hdr *hdr)
22 struct ieee80211_hw *hw = sc->pri_wiphy->hw;
25 spin_lock_bh(&sc->wiphy_lock);
26 for (i = 0; i < sc->num_sec_wiphy; i++) {
27 struct ath_wiphy *aphy = sc->sec_wiphy[i];
30 if (compare_ether_addr(hdr->addr1, aphy->hw->wiphy->perm_addr)
36 spin_unlock_bh(&sc->wiphy_lock);
41 * Setup and link descriptors.
43 * 11N: we can no longer afford to self link the last descriptor.
44 * MAC acknowledges BA status as long as it copies frames to host
45 * buffer (or rx fifo). This can incorrectly acknowledge packets
46 * to a sender if last desc is self-linked.
48 static void ath_rx_buf_link(struct ath_softc *sc, struct ath_buf *bf)
50 struct ath_hw *ah = sc->sc_ah;
57 ds->ds_link = 0; /* link to null */
58 ds->ds_data = bf->bf_buf_addr;
60 /* virtual addr of the beginning of the buffer. */
63 ds->ds_vdata = skb->data;
65 /* setup rx descriptors. The rx.bufsize here tells the harware
66 * how much data it can DMA to us and that we are prepared
68 ath9k_hw_setuprxdesc(ah, ds,
72 if (sc->rx.rxlink == NULL)
73 ath9k_hw_putrxbuf(ah, bf->bf_daddr);
75 *sc->rx.rxlink = bf->bf_daddr;
77 sc->rx.rxlink = &ds->ds_link;
81 static void ath_setdefantenna(struct ath_softc *sc, u32 antenna)
83 /* XXX block beacon interrupts */
84 ath9k_hw_setantenna(sc->sc_ah, antenna);
85 sc->rx.defant = antenna;
86 sc->rx.rxotherant = 0;
89 /* Assumes you've already done the endian to CPU conversion */
90 static bool ath9k_rx_accept(struct ath_common *common,
92 struct ieee80211_rx_status *rxs,
93 struct ath_rx_status *rx_stats,
96 struct ath_hw *ah = common->ah;
97 struct ieee80211_hdr *hdr;
100 hdr = (struct ieee80211_hdr *) skb->data;
101 fc = hdr->frame_control;
103 if (rx_stats->rs_more) {
105 * Frame spans multiple descriptors; this cannot happen yet
106 * as we don't support jumbograms. If not in monitor mode,
107 * discard the frame. Enable this if you want to see
108 * error frames in Monitor mode.
110 if (ah->opmode != NL80211_IFTYPE_MONITOR)
112 } else if (rx_stats->rs_status != 0) {
113 if (rx_stats->rs_status & ATH9K_RXERR_CRC)
114 rxs->flag |= RX_FLAG_FAILED_FCS_CRC;
115 if (rx_stats->rs_status & ATH9K_RXERR_PHY)
118 if (rx_stats->rs_status & ATH9K_RXERR_DECRYPT) {
119 *decrypt_error = true;
120 } else if (rx_stats->rs_status & ATH9K_RXERR_MIC) {
121 if (ieee80211_is_ctl(fc))
123 * Sometimes, we get invalid
124 * MIC failures on valid control frames.
125 * Remove these mic errors.
127 rx_stats->rs_status &= ~ATH9K_RXERR_MIC;
129 rxs->flag |= RX_FLAG_MMIC_ERROR;
132 * Reject error frames with the exception of
133 * decryption and MIC failures. For monitor mode,
134 * we also ignore the CRC error.
136 if (ah->opmode == NL80211_IFTYPE_MONITOR) {
137 if (rx_stats->rs_status &
138 ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC |
142 if (rx_stats->rs_status &
143 ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC)) {
151 static u8 ath9k_process_rate(struct ath_common *common,
152 struct ieee80211_hw *hw,
153 struct ath_rx_status *rx_stats,
154 struct ieee80211_rx_status *rxs,
157 struct ieee80211_supported_band *sband;
158 enum ieee80211_band band;
161 band = hw->conf.channel->band;
162 sband = hw->wiphy->bands[band];
164 if (rx_stats->rs_rate & 0x80) {
166 rxs->flag |= RX_FLAG_HT;
167 if (rx_stats->rs_flags & ATH9K_RX_2040)
168 rxs->flag |= RX_FLAG_40MHZ;
169 if (rx_stats->rs_flags & ATH9K_RX_GI)
170 rxs->flag |= RX_FLAG_SHORT_GI;
171 return rx_stats->rs_rate & 0x7f;
174 for (i = 0; i < sband->n_bitrates; i++) {
175 if (sband->bitrates[i].hw_value == rx_stats->rs_rate)
177 if (sband->bitrates[i].hw_value_short == rx_stats->rs_rate) {
178 rxs->flag |= RX_FLAG_SHORTPRE;
183 /* No valid hardware bitrate found -- we should not get here */
184 ath_print(common, ATH_DBG_XMIT, "unsupported hw bitrate detected "
185 "0x%02x using 1 Mbit\n", rx_stats->rs_rate);
186 if ((common->debug_mask & ATH_DBG_XMIT))
187 print_hex_dump_bytes("", DUMP_PREFIX_NONE, skb->data, skb->len);
193 * Theory for reporting quality:
195 * At a hardware RSSI of 45 you will be able to use MCS 7 reliably.
196 * At a hardware RSSI of 45 you will be able to use MCS 15 reliably.
197 * At a hardware RSSI of 35 you should be able use 54 Mbps reliably.
199 * MCS 7 is the highets MCS index usable by a 1-stream device.
200 * MCS 15 is the highest MCS index usable by a 2-stream device.
202 * All ath9k devices are either 1-stream or 2-stream.
204 * How many bars you see is derived from the qual reporting.
206 * A more elaborate scheme can be used here but it requires tables
207 * of SNR/throughput for each possible mode used. For the MCS table
208 * you can refer to the wireless wiki:
210 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
213 static int ath9k_compute_qual(struct ieee80211_hw *hw,
214 struct ath_rx_status *rx_stats)
218 if (conf_is_ht(&hw->conf))
219 qual = rx_stats->rs_rssi * 100 / 45;
221 qual = rx_stats->rs_rssi * 100 / 35;
224 * rssi can be more than 45 though, anything above that
225 * should be considered at 100%
233 static void ath9k_process_rssi(struct ath_common *common,
234 struct ieee80211_hw *hw,
236 struct ath_rx_status *rx_stats)
238 struct ath_hw *ah = common->ah;
239 struct ieee80211_sta *sta;
240 struct ieee80211_hdr *hdr;
242 int last_rssi = ATH_RSSI_DUMMY_MARKER;
245 hdr = (struct ieee80211_hdr *)skb->data;
246 fc = hdr->frame_control;
249 /* XXX: use ieee80211_find_sta! */
250 sta = ieee80211_find_sta_by_hw(hw, hdr->addr2);
252 an = (struct ath_node *) sta->drv_priv;
253 if (rx_stats->rs_rssi != ATH9K_RSSI_BAD &&
254 !rx_stats->rs_moreaggr)
255 ATH_RSSI_LPF(an->last_rssi, rx_stats->rs_rssi);
256 last_rssi = an->last_rssi;
260 if (likely(last_rssi != ATH_RSSI_DUMMY_MARKER))
261 rx_stats->rs_rssi = ATH_EP_RND(last_rssi,
262 ATH_RSSI_EP_MULTIPLIER);
263 if (rx_stats->rs_rssi < 0)
264 rx_stats->rs_rssi = 0;
265 else if (rx_stats->rs_rssi > 127)
266 rx_stats->rs_rssi = 127;
268 /* Update Beacon RSSI, this is used by ANI. */
269 if (ieee80211_is_beacon(fc))
270 ah->stats.avgbrssi = rx_stats->rs_rssi;
274 * For Decrypt or Demic errors, we only mark packet status here and always push
275 * up the frame up to let mac80211 handle the actual error case, be it no
276 * decryption key or real decryption error. This let us keep statistics there.
278 static int ath_rx_prepare(struct ath_common *common,
279 struct ieee80211_hw *hw,
280 struct sk_buff *skb, struct ath_rx_status *rx_stats,
281 struct ieee80211_rx_status *rx_status,
284 struct ath_hw *ah = common->ah;
286 memset(rx_status, 0, sizeof(struct ieee80211_rx_status));
288 if (!ath9k_rx_accept(common, skb, rx_status, rx_stats, decrypt_error))
291 ath9k_process_rssi(common, hw, skb, rx_stats);
293 rx_status->rate_idx = ath9k_process_rate(common, hw,
294 rx_stats, rx_status, skb);
295 rx_status->mactime = ath9k_hw_extend_tsf(ah, rx_stats->rs_tstamp);
296 rx_status->band = hw->conf.channel->band;
297 rx_status->freq = hw->conf.channel->center_freq;
298 rx_status->noise = common->ani.noise_floor;
299 rx_status->signal = ATH_DEFAULT_NOISE_FLOOR + rx_stats->rs_rssi;
300 rx_status->antenna = rx_stats->rs_antenna;
301 rx_status->qual = ath9k_compute_qual(hw, rx_stats);
302 rx_status->flag |= RX_FLAG_TSFT;
309 static void ath_opmode_init(struct ath_softc *sc)
311 struct ath_hw *ah = sc->sc_ah;
312 struct ath_common *common = ath9k_hw_common(ah);
316 /* configure rx filter */
317 rfilt = ath_calcrxfilter(sc);
318 ath9k_hw_setrxfilter(ah, rfilt);
320 /* configure bssid mask */
321 if (ah->caps.hw_caps & ATH9K_HW_CAP_BSSIDMASK)
322 ath_hw_setbssidmask(common);
324 /* configure operational mode */
325 ath9k_hw_setopmode(ah);
327 /* Handle any link-level address change. */
328 ath9k_hw_setmac(ah, common->macaddr);
330 /* calculate and install multicast filter */
331 mfilt[0] = mfilt[1] = ~0;
332 ath9k_hw_setmcastfilter(ah, mfilt[0], mfilt[1]);
335 int ath_rx_init(struct ath_softc *sc, int nbufs)
337 struct ath_common *common = ath9k_hw_common(sc->sc_ah);
342 spin_lock_init(&sc->rx.rxflushlock);
343 sc->sc_flags &= ~SC_OP_RXFLUSH;
344 spin_lock_init(&sc->rx.rxbuflock);
346 sc->rx.bufsize = roundup(IEEE80211_MAX_MPDU_LEN,
347 min(common->cachelsz, (u16)64));
349 ath_print(common, ATH_DBG_CONFIG, "cachelsz %u rxbufsize %u\n",
350 common->cachelsz, sc->rx.bufsize);
352 /* Initialize rx descriptors */
354 error = ath_descdma_setup(sc, &sc->rx.rxdma, &sc->rx.rxbuf,
357 ath_print(common, ATH_DBG_FATAL,
358 "failed to allocate rx descriptors: %d\n", error);
362 list_for_each_entry(bf, &sc->rx.rxbuf, list) {
363 skb = ath_rxbuf_alloc(common, sc->rx.bufsize, GFP_KERNEL);
370 bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
373 if (unlikely(dma_mapping_error(sc->dev,
375 dev_kfree_skb_any(skb);
377 ath_print(common, ATH_DBG_FATAL,
378 "dma_mapping_error() on RX init\n");
382 bf->bf_dmacontext = bf->bf_buf_addr;
384 sc->rx.rxlink = NULL;
393 void ath_rx_cleanup(struct ath_softc *sc)
398 list_for_each_entry(bf, &sc->rx.rxbuf, list) {
401 dma_unmap_single(sc->dev, bf->bf_buf_addr,
402 sc->rx.bufsize, DMA_FROM_DEVICE);
407 if (sc->rx.rxdma.dd_desc_len != 0)
408 ath_descdma_cleanup(sc, &sc->rx.rxdma, &sc->rx.rxbuf);
412 * Calculate the receive filter according to the
413 * operating mode and state:
415 * o always accept unicast, broadcast, and multicast traffic
416 * o maintain current state of phy error reception (the hal
417 * may enable phy error frames for noise immunity work)
418 * o probe request frames are accepted only when operating in
419 * hostap, adhoc, or monitor modes
420 * o enable promiscuous mode according to the interface state
422 * - when operating in adhoc mode so the 802.11 layer creates
423 * node table entries for peers,
424 * - when operating in station mode for collecting rssi data when
425 * the station is otherwise quiet, or
426 * - when operating as a repeater so we see repeater-sta beacons
430 u32 ath_calcrxfilter(struct ath_softc *sc)
432 #define RX_FILTER_PRESERVE (ATH9K_RX_FILTER_PHYERR | ATH9K_RX_FILTER_PHYRADAR)
436 rfilt = (ath9k_hw_getrxfilter(sc->sc_ah) & RX_FILTER_PRESERVE)
437 | ATH9K_RX_FILTER_UCAST | ATH9K_RX_FILTER_BCAST
438 | ATH9K_RX_FILTER_MCAST;
440 /* If not a STA, enable processing of Probe Requests */
441 if (sc->sc_ah->opmode != NL80211_IFTYPE_STATION)
442 rfilt |= ATH9K_RX_FILTER_PROBEREQ;
445 * Set promiscuous mode when FIF_PROMISC_IN_BSS is enabled for station
446 * mode interface or when in monitor mode. AP mode does not need this
447 * since it receives all in-BSS frames anyway.
449 if (((sc->sc_ah->opmode != NL80211_IFTYPE_AP) &&
450 (sc->rx.rxfilter & FIF_PROMISC_IN_BSS)) ||
451 (sc->sc_ah->opmode == NL80211_IFTYPE_MONITOR))
452 rfilt |= ATH9K_RX_FILTER_PROM;
454 if (sc->rx.rxfilter & FIF_CONTROL)
455 rfilt |= ATH9K_RX_FILTER_CONTROL;
457 if ((sc->sc_ah->opmode == NL80211_IFTYPE_STATION) &&
458 !(sc->rx.rxfilter & FIF_BCN_PRBRESP_PROMISC))
459 rfilt |= ATH9K_RX_FILTER_MYBEACON;
461 rfilt |= ATH9K_RX_FILTER_BEACON;
463 if ((AR_SREV_9280_10_OR_LATER(sc->sc_ah) ||
464 AR_SREV_9285_10_OR_LATER(sc->sc_ah)) &&
465 (sc->sc_ah->opmode == NL80211_IFTYPE_AP) &&
466 (sc->rx.rxfilter & FIF_PSPOLL))
467 rfilt |= ATH9K_RX_FILTER_PSPOLL;
469 if (conf_is_ht(&sc->hw->conf))
470 rfilt |= ATH9K_RX_FILTER_COMP_BAR;
472 if (sc->sec_wiphy || (sc->rx.rxfilter & FIF_OTHER_BSS)) {
473 /* TODO: only needed if more than one BSSID is in use in
474 * station/adhoc mode */
475 /* The following may also be needed for other older chips */
476 if (sc->sc_ah->hw_version.macVersion == AR_SREV_VERSION_9160)
477 rfilt |= ATH9K_RX_FILTER_PROM;
478 rfilt |= ATH9K_RX_FILTER_MCAST_BCAST_ALL;
483 #undef RX_FILTER_PRESERVE
486 int ath_startrecv(struct ath_softc *sc)
488 struct ath_hw *ah = sc->sc_ah;
489 struct ath_buf *bf, *tbf;
491 spin_lock_bh(&sc->rx.rxbuflock);
492 if (list_empty(&sc->rx.rxbuf))
495 sc->rx.rxlink = NULL;
496 list_for_each_entry_safe(bf, tbf, &sc->rx.rxbuf, list) {
497 ath_rx_buf_link(sc, bf);
500 /* We could have deleted elements so the list may be empty now */
501 if (list_empty(&sc->rx.rxbuf))
504 bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
505 ath9k_hw_putrxbuf(ah, bf->bf_daddr);
509 spin_unlock_bh(&sc->rx.rxbuflock);
511 ath9k_hw_startpcureceive(ah);
516 bool ath_stoprecv(struct ath_softc *sc)
518 struct ath_hw *ah = sc->sc_ah;
521 ath9k_hw_stoppcurecv(ah);
522 ath9k_hw_setrxfilter(ah, 0);
523 stopped = ath9k_hw_stopdmarecv(ah);
524 sc->rx.rxlink = NULL;
529 void ath_flushrecv(struct ath_softc *sc)
531 spin_lock_bh(&sc->rx.rxflushlock);
532 sc->sc_flags |= SC_OP_RXFLUSH;
533 ath_rx_tasklet(sc, 1);
534 sc->sc_flags &= ~SC_OP_RXFLUSH;
535 spin_unlock_bh(&sc->rx.rxflushlock);
538 static bool ath_beacon_dtim_pending_cab(struct sk_buff *skb)
540 /* Check whether the Beacon frame has DTIM indicating buffered bc/mc */
541 struct ieee80211_mgmt *mgmt;
542 u8 *pos, *end, id, elen;
543 struct ieee80211_tim_ie *tim;
545 mgmt = (struct ieee80211_mgmt *)skb->data;
546 pos = mgmt->u.beacon.variable;
547 end = skb->data + skb->len;
549 while (pos + 2 < end) {
552 if (pos + elen > end)
555 if (id == WLAN_EID_TIM) {
556 if (elen < sizeof(*tim))
558 tim = (struct ieee80211_tim_ie *) pos;
559 if (tim->dtim_count != 0)
561 return tim->bitmap_ctrl & 0x01;
570 static void ath_rx_ps_beacon(struct ath_softc *sc, struct sk_buff *skb)
572 struct ieee80211_mgmt *mgmt;
573 struct ath_common *common = ath9k_hw_common(sc->sc_ah);
575 if (skb->len < 24 + 8 + 2 + 2)
578 mgmt = (struct ieee80211_mgmt *)skb->data;
579 if (memcmp(common->curbssid, mgmt->bssid, ETH_ALEN) != 0)
580 return; /* not from our current AP */
582 sc->sc_flags &= ~SC_OP_WAIT_FOR_BEACON;
584 if (sc->sc_flags & SC_OP_BEACON_SYNC) {
585 sc->sc_flags &= ~SC_OP_BEACON_SYNC;
586 ath_print(common, ATH_DBG_PS,
587 "Reconfigure Beacon timers based on "
588 "timestamp from the AP\n");
589 ath_beacon_config(sc, NULL);
592 if (ath_beacon_dtim_pending_cab(skb)) {
594 * Remain awake waiting for buffered broadcast/multicast
595 * frames. If the last broadcast/multicast frame is not
596 * received properly, the next beacon frame will work as
597 * a backup trigger for returning into NETWORK SLEEP state,
598 * so we are waiting for it as well.
600 ath_print(common, ATH_DBG_PS, "Received DTIM beacon indicating "
601 "buffered broadcast/multicast frame(s)\n");
602 sc->sc_flags |= SC_OP_WAIT_FOR_CAB | SC_OP_WAIT_FOR_BEACON;
606 if (sc->sc_flags & SC_OP_WAIT_FOR_CAB) {
608 * This can happen if a broadcast frame is dropped or the AP
609 * fails to send a frame indicating that all CAB frames have
612 sc->sc_flags &= ~SC_OP_WAIT_FOR_CAB;
613 ath_print(common, ATH_DBG_PS,
614 "PS wait for CAB frames timed out\n");
618 static void ath_rx_ps(struct ath_softc *sc, struct sk_buff *skb)
620 struct ieee80211_hdr *hdr;
621 struct ath_common *common = ath9k_hw_common(sc->sc_ah);
623 hdr = (struct ieee80211_hdr *)skb->data;
625 /* Process Beacon and CAB receive in PS state */
626 if ((sc->sc_flags & SC_OP_WAIT_FOR_BEACON) &&
627 ieee80211_is_beacon(hdr->frame_control))
628 ath_rx_ps_beacon(sc, skb);
629 else if ((sc->sc_flags & SC_OP_WAIT_FOR_CAB) &&
630 (ieee80211_is_data(hdr->frame_control) ||
631 ieee80211_is_action(hdr->frame_control)) &&
632 is_multicast_ether_addr(hdr->addr1) &&
633 !ieee80211_has_moredata(hdr->frame_control)) {
635 * No more broadcast/multicast frames to be received at this
638 sc->sc_flags &= ~SC_OP_WAIT_FOR_CAB;
639 ath_print(common, ATH_DBG_PS,
640 "All PS CAB frames received, back to sleep\n");
641 } else if ((sc->sc_flags & SC_OP_WAIT_FOR_PSPOLL_DATA) &&
642 !is_multicast_ether_addr(hdr->addr1) &&
643 !ieee80211_has_morefrags(hdr->frame_control)) {
644 sc->sc_flags &= ~SC_OP_WAIT_FOR_PSPOLL_DATA;
645 ath_print(common, ATH_DBG_PS,
646 "Going back to sleep after having received "
647 "PS-Poll data (0x%x)\n",
648 sc->sc_flags & (SC_OP_WAIT_FOR_BEACON |
650 SC_OP_WAIT_FOR_PSPOLL_DATA |
651 SC_OP_WAIT_FOR_TX_ACK));
655 static void ath_rx_send_to_mac80211(struct ieee80211_hw *hw,
656 struct ath_softc *sc, struct sk_buff *skb,
657 struct ieee80211_rx_status *rx_status)
659 struct ieee80211_hdr *hdr;
661 hdr = (struct ieee80211_hdr *)skb->data;
663 /* Send the frame to mac80211 */
664 if (is_multicast_ether_addr(hdr->addr1)) {
667 * Deliver broadcast/multicast frames to all suitable
670 /* TODO: filter based on channel configuration */
671 for (i = 0; i < sc->num_sec_wiphy; i++) {
672 struct ath_wiphy *aphy = sc->sec_wiphy[i];
673 struct sk_buff *nskb;
676 nskb = skb_copy(skb, GFP_ATOMIC);
678 memcpy(IEEE80211_SKB_RXCB(nskb), rx_status,
680 ieee80211_rx(aphy->hw, nskb);
683 memcpy(IEEE80211_SKB_RXCB(skb), rx_status, sizeof(*rx_status));
684 ieee80211_rx(sc->hw, skb);
686 /* Deliver unicast frames based on receiver address */
687 memcpy(IEEE80211_SKB_RXCB(skb), rx_status, sizeof(*rx_status));
688 ieee80211_rx(hw, skb);
692 int ath_rx_tasklet(struct ath_softc *sc, int flush)
694 #define PA2DESC(_sc, _pa) \
695 ((struct ath_desc *)((caddr_t)(_sc)->rx.rxdma.dd_desc + \
696 ((_pa) - (_sc)->rx.rxdma.dd_desc_paddr)))
700 struct ath_rx_status *rx_stats;
701 struct sk_buff *skb = NULL, *requeue_skb;
702 struct ieee80211_rx_status rx_status;
703 struct ath_hw *ah = sc->sc_ah;
704 struct ath_common *common = ath9k_hw_common(ah);
706 * The hw can techncically differ from common->hw when using ath9k
707 * virtual wiphy so to account for that we iterate over the active
708 * wiphys and find the appropriate wiphy and therefore hw.
710 struct ieee80211_hw *hw = NULL;
711 struct ieee80211_hdr *hdr;
712 int hdrlen, padsize, retval;
713 bool decrypt_error = false;
717 spin_lock_bh(&sc->rx.rxbuflock);
720 /* If handling rx interrupt and flush is in progress => exit */
721 if ((sc->sc_flags & SC_OP_RXFLUSH) && (flush == 0))
724 if (list_empty(&sc->rx.rxbuf)) {
725 sc->rx.rxlink = NULL;
729 bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
733 * Must provide the virtual address of the current
734 * descriptor, the physical address, and the virtual
735 * address of the next descriptor in the h/w chain.
736 * This allows the HAL to look ahead to see if the
737 * hardware is done with a descriptor by checking the
738 * done bit in the following descriptor and the address
739 * of the current descriptor the DMA engine is working
740 * on. All this is necessary because of our use of
741 * a self-linked list to avoid rx overruns.
743 retval = ath9k_hw_rxprocdesc(ah, ds,
745 PA2DESC(sc, ds->ds_link),
747 if (retval == -EINPROGRESS) {
749 struct ath_desc *tds;
751 if (list_is_last(&bf->list, &sc->rx.rxbuf)) {
752 sc->rx.rxlink = NULL;
756 tbf = list_entry(bf->list.next, struct ath_buf, list);
759 * On some hardware the descriptor status words could
760 * get corrupted, including the done bit. Because of
761 * this, check if the next descriptor's done bit is
764 * If the next descriptor's done bit is set, the current
765 * descriptor has been corrupted. Force s/w to discard
766 * this descriptor and continue...
770 retval = ath9k_hw_rxprocdesc(ah, tds, tbf->bf_daddr,
771 PA2DESC(sc, tds->ds_link), 0);
772 if (retval == -EINPROGRESS) {
782 * Synchronize the DMA transfer with CPU before
783 * 1. accessing the frame
784 * 2. requeueing the same buffer to h/w
786 dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
790 hdr = (struct ieee80211_hdr *) skb->data;
791 hw = ath_get_virt_hw(sc, hdr);
792 rx_stats = &ds->ds_rxstat;
795 * If we're asked to flush receive queue, directly
796 * chain it back at the queue without processing it.
801 if (!rx_stats->rs_datalen)
804 /* The status portion of the descriptor could get corrupted. */
805 if (sc->rx.bufsize < rx_stats->rs_datalen)
808 if (!ath_rx_prepare(common, hw, skb, rx_stats,
809 &rx_status, &decrypt_error))
812 /* Ensure we always have an skb to requeue once we are done
813 * processing the current buffer's skb */
814 requeue_skb = ath_rxbuf_alloc(common, sc->rx.bufsize, GFP_ATOMIC);
816 /* If there is no memory we ignore the current RX'd frame,
817 * tell hardware it can give us a new frame using the old
818 * skb and put it at the tail of the sc->rx.rxbuf list for
823 /* Unmap the frame */
824 dma_unmap_single(sc->dev, bf->bf_buf_addr,
828 skb_put(skb, rx_stats->rs_datalen);
830 /* see if any padding is done by the hw and remove it */
831 hdrlen = ieee80211_get_hdrlen_from_skb(skb);
832 fc = hdr->frame_control;
834 /* The MAC header is padded to have 32-bit boundary if the
835 * packet payload is non-zero. The general calculation for
836 * padsize would take into account odd header lengths:
837 * padsize = (4 - hdrlen % 4) % 4; However, since only
838 * even-length headers are used, padding can only be 0 or 2
839 * bytes and we can optimize this a bit. In addition, we must
840 * not try to remove padding from short control frames that do
841 * not have payload. */
842 padsize = hdrlen & 3;
843 if (padsize && hdrlen >= 24) {
844 memmove(skb->data + padsize, skb->data, hdrlen);
845 skb_pull(skb, padsize);
848 keyix = rx_stats->rs_keyix;
850 if (!(keyix == ATH9K_RXKEYIX_INVALID) && !decrypt_error) {
851 rx_status.flag |= RX_FLAG_DECRYPTED;
852 } else if (ieee80211_has_protected(fc)
853 && !decrypt_error && skb->len >= hdrlen + 4) {
854 keyix = skb->data[hdrlen + 3] >> 6;
856 if (test_bit(keyix, sc->keymap))
857 rx_status.flag |= RX_FLAG_DECRYPTED;
859 if (ah->sw_mgmt_crypto &&
860 (rx_status.flag & RX_FLAG_DECRYPTED) &&
861 ieee80211_is_mgmt(fc)) {
862 /* Use software decrypt for management frames. */
863 rx_status.flag &= ~RX_FLAG_DECRYPTED;
866 /* We will now give hardware our shiny new allocated skb */
867 bf->bf_mpdu = requeue_skb;
868 bf->bf_buf_addr = dma_map_single(sc->dev, requeue_skb->data,
871 if (unlikely(dma_mapping_error(sc->dev,
873 dev_kfree_skb_any(requeue_skb);
875 ath_print(common, ATH_DBG_FATAL,
876 "dma_mapping_error() on RX\n");
877 ath_rx_send_to_mac80211(hw, sc, skb, &rx_status);
880 bf->bf_dmacontext = bf->bf_buf_addr;
883 * change the default rx antenna if rx diversity chooses the
884 * other antenna 3 times in a row.
886 if (sc->rx.defant != ds->ds_rxstat.rs_antenna) {
887 if (++sc->rx.rxotherant >= 3)
888 ath_setdefantenna(sc, rx_stats->rs_antenna);
890 sc->rx.rxotherant = 0;
893 if (unlikely(sc->sc_flags & (SC_OP_WAIT_FOR_BEACON |
895 SC_OP_WAIT_FOR_PSPOLL_DATA)))
898 ath_rx_send_to_mac80211(hw, sc, skb, &rx_status);
901 list_move_tail(&bf->list, &sc->rx.rxbuf);
902 ath_rx_buf_link(sc, bf);
905 spin_unlock_bh(&sc->rx.rxbuflock);