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;
90 * Extend 15-bit time stamp from rx descriptor to
91 * a full 64-bit TSF using the current h/w TSF.
93 static u64 ath_extend_tsf(struct ath_softc *sc, u32 rstamp)
97 tsf = ath9k_hw_gettsf64(sc->sc_ah);
98 if ((tsf & 0x7fff) < rstamp)
100 return (tsf & ~0x7fff) | rstamp;
104 * For Decrypt or Demic errors, we only mark packet status here and always push
105 * up the frame up to let mac80211 handle the actual error case, be it no
106 * decryption key or real decryption error. This let us keep statistics there.
108 static int ath_rx_prepare(struct sk_buff *skb, struct ath_desc *ds,
109 struct ieee80211_rx_status *rx_status, bool *decrypt_error,
110 struct ath_softc *sc)
112 struct ieee80211_hdr *hdr;
115 struct ieee80211_hw *hw;
116 struct ieee80211_sta *sta;
118 int last_rssi = ATH_RSSI_DUMMY_MARKER;
121 hdr = (struct ieee80211_hdr *)skb->data;
122 fc = hdr->frame_control;
123 memset(rx_status, 0, sizeof(struct ieee80211_rx_status));
124 hw = ath_get_virt_hw(sc, hdr);
126 if (ds->ds_rxstat.rs_more) {
128 * Frame spans multiple descriptors; this cannot happen yet
129 * as we don't support jumbograms. If not in monitor mode,
130 * discard the frame. Enable this if you want to see
131 * error frames in Monitor mode.
133 if (sc->sc_ah->opmode != NL80211_IFTYPE_MONITOR)
135 } else if (ds->ds_rxstat.rs_status != 0) {
136 if (ds->ds_rxstat.rs_status & ATH9K_RXERR_CRC)
137 rx_status->flag |= RX_FLAG_FAILED_FCS_CRC;
138 if (ds->ds_rxstat.rs_status & ATH9K_RXERR_PHY)
141 if (ds->ds_rxstat.rs_status & ATH9K_RXERR_DECRYPT) {
142 *decrypt_error = true;
143 } else if (ds->ds_rxstat.rs_status & ATH9K_RXERR_MIC) {
144 if (ieee80211_is_ctl(fc))
146 * Sometimes, we get invalid
147 * MIC failures on valid control frames.
148 * Remove these mic errors.
150 ds->ds_rxstat.rs_status &= ~ATH9K_RXERR_MIC;
152 rx_status->flag |= RX_FLAG_MMIC_ERROR;
155 * Reject error frames with the exception of
156 * decryption and MIC failures. For monitor mode,
157 * we also ignore the CRC error.
159 if (sc->sc_ah->opmode == NL80211_IFTYPE_MONITOR) {
160 if (ds->ds_rxstat.rs_status &
161 ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC |
165 if (ds->ds_rxstat.rs_status &
166 ~(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC)) {
172 ratecode = ds->ds_rxstat.rs_rate;
174 if (ratecode & 0x80) {
176 rx_status->flag |= RX_FLAG_HT;
177 if (ds->ds_rxstat.rs_flags & ATH9K_RX_2040)
178 rx_status->flag |= RX_FLAG_40MHZ;
179 if (ds->ds_rxstat.rs_flags & ATH9K_RX_GI)
180 rx_status->flag |= RX_FLAG_SHORT_GI;
181 rx_status->rate_idx = ratecode & 0x7f;
183 int i = 0, cur_band, n_rates;
185 cur_band = hw->conf.channel->band;
186 n_rates = sc->sbands[cur_band].n_bitrates;
188 for (i = 0; i < n_rates; i++) {
189 if (sc->sbands[cur_band].bitrates[i].hw_value ==
191 rx_status->rate_idx = i;
195 if (sc->sbands[cur_band].bitrates[i].hw_value_short ==
197 rx_status->rate_idx = i;
198 rx_status->flag |= RX_FLAG_SHORTPRE;
205 /* XXX: use ieee80211_find_sta! */
206 sta = ieee80211_find_sta_by_hw(sc->hw, hdr->addr2);
208 an = (struct ath_node *) sta->drv_priv;
209 if (ds->ds_rxstat.rs_rssi != ATH9K_RSSI_BAD &&
210 !ds->ds_rxstat.rs_moreaggr)
211 ATH_RSSI_LPF(an->last_rssi, ds->ds_rxstat.rs_rssi);
212 last_rssi = an->last_rssi;
216 if (likely(last_rssi != ATH_RSSI_DUMMY_MARKER))
217 ds->ds_rxstat.rs_rssi = ATH_EP_RND(last_rssi,
218 ATH_RSSI_EP_MULTIPLIER);
219 if (ds->ds_rxstat.rs_rssi < 0)
220 ds->ds_rxstat.rs_rssi = 0;
221 else if (ds->ds_rxstat.rs_rssi > 127)
222 ds->ds_rxstat.rs_rssi = 127;
224 /* Update Beacon RSSI, this is used by ANI. */
225 if (ieee80211_is_beacon(fc))
226 sc->sc_ah->stats.avgbrssi = ds->ds_rxstat.rs_rssi;
228 rx_status->mactime = ath_extend_tsf(sc, ds->ds_rxstat.rs_tstamp);
229 rx_status->band = hw->conf.channel->band;
230 rx_status->freq = hw->conf.channel->center_freq;
231 rx_status->noise = sc->ani.noise_floor;
232 rx_status->signal = ATH_DEFAULT_NOISE_FLOOR + ds->ds_rxstat.rs_rssi;
233 rx_status->antenna = ds->ds_rxstat.rs_antenna;
236 * Theory for reporting quality:
238 * At a hardware RSSI of 45 you will be able to use MCS 7 reliably.
239 * At a hardware RSSI of 45 you will be able to use MCS 15 reliably.
240 * At a hardware RSSI of 35 you should be able use 54 Mbps reliably.
242 * MCS 7 is the highets MCS index usable by a 1-stream device.
243 * MCS 15 is the highest MCS index usable by a 2-stream device.
245 * All ath9k devices are either 1-stream or 2-stream.
247 * How many bars you see is derived from the qual reporting.
249 * A more elaborate scheme can be used here but it requires tables
250 * of SNR/throughput for each possible mode used. For the MCS table
251 * you can refer to the wireless wiki:
253 * http://wireless.kernel.org/en/developers/Documentation/ieee80211/802.11n
256 if (conf_is_ht(&hw->conf))
257 rx_status->qual = ds->ds_rxstat.rs_rssi * 100 / 45;
259 rx_status->qual = ds->ds_rxstat.rs_rssi * 100 / 35;
261 /* rssi can be more than 45 though, anything above that
262 * should be considered at 100% */
263 if (rx_status->qual > 100)
264 rx_status->qual = 100;
266 rx_status->flag |= RX_FLAG_TSFT;
273 static void ath_opmode_init(struct ath_softc *sc)
275 struct ath_hw *ah = sc->sc_ah;
276 struct ath_common *common = ath9k_hw_common(ah);
280 /* configure rx filter */
281 rfilt = ath_calcrxfilter(sc);
282 ath9k_hw_setrxfilter(ah, rfilt);
284 /* configure bssid mask */
285 if (ah->caps.hw_caps & ATH9K_HW_CAP_BSSIDMASK)
286 ath_hw_setbssidmask(common);
288 /* configure operational mode */
289 ath9k_hw_setopmode(ah);
291 /* Handle any link-level address change. */
292 ath9k_hw_setmac(ah, common->macaddr);
294 /* calculate and install multicast filter */
295 mfilt[0] = mfilt[1] = ~0;
296 ath9k_hw_setmcastfilter(ah, mfilt[0], mfilt[1]);
299 int ath_rx_init(struct ath_softc *sc, int nbufs)
301 struct ath_common *common = ath9k_hw_common(sc->sc_ah);
306 spin_lock_init(&sc->rx.rxflushlock);
307 sc->sc_flags &= ~SC_OP_RXFLUSH;
308 spin_lock_init(&sc->rx.rxbuflock);
310 sc->rx.bufsize = roundup(IEEE80211_MAX_MPDU_LEN,
311 min(common->cachelsz, (u16)64));
313 ath_print(common, ATH_DBG_CONFIG, "cachelsz %u rxbufsize %u\n",
314 common->cachelsz, sc->rx.bufsize);
316 /* Initialize rx descriptors */
318 error = ath_descdma_setup(sc, &sc->rx.rxdma, &sc->rx.rxbuf,
321 ath_print(common, ATH_DBG_FATAL,
322 "failed to allocate rx descriptors: %d\n", error);
326 list_for_each_entry(bf, &sc->rx.rxbuf, list) {
327 skb = ath_rxbuf_alloc(common, sc->rx.bufsize, GFP_KERNEL);
334 bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
337 if (unlikely(dma_mapping_error(sc->dev,
339 dev_kfree_skb_any(skb);
341 ath_print(common, ATH_DBG_FATAL,
342 "dma_mapping_error() on RX init\n");
346 bf->bf_dmacontext = bf->bf_buf_addr;
348 sc->rx.rxlink = NULL;
357 void ath_rx_cleanup(struct ath_softc *sc)
362 list_for_each_entry(bf, &sc->rx.rxbuf, list) {
365 dma_unmap_single(sc->dev, bf->bf_buf_addr,
366 sc->rx.bufsize, DMA_FROM_DEVICE);
371 if (sc->rx.rxdma.dd_desc_len != 0)
372 ath_descdma_cleanup(sc, &sc->rx.rxdma, &sc->rx.rxbuf);
376 * Calculate the receive filter according to the
377 * operating mode and state:
379 * o always accept unicast, broadcast, and multicast traffic
380 * o maintain current state of phy error reception (the hal
381 * may enable phy error frames for noise immunity work)
382 * o probe request frames are accepted only when operating in
383 * hostap, adhoc, or monitor modes
384 * o enable promiscuous mode according to the interface state
386 * - when operating in adhoc mode so the 802.11 layer creates
387 * node table entries for peers,
388 * - when operating in station mode for collecting rssi data when
389 * the station is otherwise quiet, or
390 * - when operating as a repeater so we see repeater-sta beacons
394 u32 ath_calcrxfilter(struct ath_softc *sc)
396 #define RX_FILTER_PRESERVE (ATH9K_RX_FILTER_PHYERR | ATH9K_RX_FILTER_PHYRADAR)
400 rfilt = (ath9k_hw_getrxfilter(sc->sc_ah) & RX_FILTER_PRESERVE)
401 | ATH9K_RX_FILTER_UCAST | ATH9K_RX_FILTER_BCAST
402 | ATH9K_RX_FILTER_MCAST;
404 /* If not a STA, enable processing of Probe Requests */
405 if (sc->sc_ah->opmode != NL80211_IFTYPE_STATION)
406 rfilt |= ATH9K_RX_FILTER_PROBEREQ;
409 * Set promiscuous mode when FIF_PROMISC_IN_BSS is enabled for station
410 * mode interface or when in monitor mode. AP mode does not need this
411 * since it receives all in-BSS frames anyway.
413 if (((sc->sc_ah->opmode != NL80211_IFTYPE_AP) &&
414 (sc->rx.rxfilter & FIF_PROMISC_IN_BSS)) ||
415 (sc->sc_ah->opmode == NL80211_IFTYPE_MONITOR))
416 rfilt |= ATH9K_RX_FILTER_PROM;
418 if (sc->rx.rxfilter & FIF_CONTROL)
419 rfilt |= ATH9K_RX_FILTER_CONTROL;
421 if ((sc->sc_ah->opmode == NL80211_IFTYPE_STATION) &&
422 !(sc->rx.rxfilter & FIF_BCN_PRBRESP_PROMISC))
423 rfilt |= ATH9K_RX_FILTER_MYBEACON;
425 rfilt |= ATH9K_RX_FILTER_BEACON;
427 if ((AR_SREV_9280_10_OR_LATER(sc->sc_ah) ||
428 AR_SREV_9285_10_OR_LATER(sc->sc_ah)) &&
429 (sc->sc_ah->opmode == NL80211_IFTYPE_AP) &&
430 (sc->rx.rxfilter & FIF_PSPOLL))
431 rfilt |= ATH9K_RX_FILTER_PSPOLL;
433 if (conf_is_ht(&sc->hw->conf))
434 rfilt |= ATH9K_RX_FILTER_COMP_BAR;
436 if (sc->sec_wiphy || (sc->rx.rxfilter & FIF_OTHER_BSS)) {
437 /* TODO: only needed if more than one BSSID is in use in
438 * station/adhoc mode */
439 /* The following may also be needed for other older chips */
440 if (sc->sc_ah->hw_version.macVersion == AR_SREV_VERSION_9160)
441 rfilt |= ATH9K_RX_FILTER_PROM;
442 rfilt |= ATH9K_RX_FILTER_MCAST_BCAST_ALL;
447 #undef RX_FILTER_PRESERVE
450 int ath_startrecv(struct ath_softc *sc)
452 struct ath_hw *ah = sc->sc_ah;
453 struct ath_buf *bf, *tbf;
455 spin_lock_bh(&sc->rx.rxbuflock);
456 if (list_empty(&sc->rx.rxbuf))
459 sc->rx.rxlink = NULL;
460 list_for_each_entry_safe(bf, tbf, &sc->rx.rxbuf, list) {
461 ath_rx_buf_link(sc, bf);
464 /* We could have deleted elements so the list may be empty now */
465 if (list_empty(&sc->rx.rxbuf))
468 bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
469 ath9k_hw_putrxbuf(ah, bf->bf_daddr);
473 spin_unlock_bh(&sc->rx.rxbuflock);
475 ath9k_hw_startpcureceive(ah);
480 bool ath_stoprecv(struct ath_softc *sc)
482 struct ath_hw *ah = sc->sc_ah;
485 ath9k_hw_stoppcurecv(ah);
486 ath9k_hw_setrxfilter(ah, 0);
487 stopped = ath9k_hw_stopdmarecv(ah);
488 sc->rx.rxlink = NULL;
493 void ath_flushrecv(struct ath_softc *sc)
495 spin_lock_bh(&sc->rx.rxflushlock);
496 sc->sc_flags |= SC_OP_RXFLUSH;
497 ath_rx_tasklet(sc, 1);
498 sc->sc_flags &= ~SC_OP_RXFLUSH;
499 spin_unlock_bh(&sc->rx.rxflushlock);
502 static bool ath_beacon_dtim_pending_cab(struct sk_buff *skb)
504 /* Check whether the Beacon frame has DTIM indicating buffered bc/mc */
505 struct ieee80211_mgmt *mgmt;
506 u8 *pos, *end, id, elen;
507 struct ieee80211_tim_ie *tim;
509 mgmt = (struct ieee80211_mgmt *)skb->data;
510 pos = mgmt->u.beacon.variable;
511 end = skb->data + skb->len;
513 while (pos + 2 < end) {
516 if (pos + elen > end)
519 if (id == WLAN_EID_TIM) {
520 if (elen < sizeof(*tim))
522 tim = (struct ieee80211_tim_ie *) pos;
523 if (tim->dtim_count != 0)
525 return tim->bitmap_ctrl & 0x01;
534 static void ath_rx_ps_beacon(struct ath_softc *sc, struct sk_buff *skb)
536 struct ieee80211_mgmt *mgmt;
537 struct ath_common *common = ath9k_hw_common(sc->sc_ah);
539 if (skb->len < 24 + 8 + 2 + 2)
542 mgmt = (struct ieee80211_mgmt *)skb->data;
543 if (memcmp(common->curbssid, mgmt->bssid, ETH_ALEN) != 0)
544 return; /* not from our current AP */
546 sc->sc_flags &= ~SC_OP_WAIT_FOR_BEACON;
548 if (sc->sc_flags & SC_OP_BEACON_SYNC) {
549 sc->sc_flags &= ~SC_OP_BEACON_SYNC;
550 ath_print(common, ATH_DBG_PS,
551 "Reconfigure Beacon timers based on "
552 "timestamp from the AP\n");
553 ath_beacon_config(sc, NULL);
556 if (ath_beacon_dtim_pending_cab(skb)) {
558 * Remain awake waiting for buffered broadcast/multicast
559 * frames. If the last broadcast/multicast frame is not
560 * received properly, the next beacon frame will work as
561 * a backup trigger for returning into NETWORK SLEEP state,
562 * so we are waiting for it as well.
564 ath_print(common, ATH_DBG_PS, "Received DTIM beacon indicating "
565 "buffered broadcast/multicast frame(s)\n");
566 sc->sc_flags |= SC_OP_WAIT_FOR_CAB | SC_OP_WAIT_FOR_BEACON;
570 if (sc->sc_flags & SC_OP_WAIT_FOR_CAB) {
572 * This can happen if a broadcast frame is dropped or the AP
573 * fails to send a frame indicating that all CAB frames have
576 sc->sc_flags &= ~SC_OP_WAIT_FOR_CAB;
577 ath_print(common, ATH_DBG_PS,
578 "PS wait for CAB frames timed out\n");
582 static void ath_rx_ps(struct ath_softc *sc, struct sk_buff *skb)
584 struct ieee80211_hdr *hdr;
585 struct ath_common *common = ath9k_hw_common(sc->sc_ah);
587 hdr = (struct ieee80211_hdr *)skb->data;
589 /* Process Beacon and CAB receive in PS state */
590 if ((sc->sc_flags & SC_OP_WAIT_FOR_BEACON) &&
591 ieee80211_is_beacon(hdr->frame_control))
592 ath_rx_ps_beacon(sc, skb);
593 else if ((sc->sc_flags & SC_OP_WAIT_FOR_CAB) &&
594 (ieee80211_is_data(hdr->frame_control) ||
595 ieee80211_is_action(hdr->frame_control)) &&
596 is_multicast_ether_addr(hdr->addr1) &&
597 !ieee80211_has_moredata(hdr->frame_control)) {
599 * No more broadcast/multicast frames to be received at this
602 sc->sc_flags &= ~SC_OP_WAIT_FOR_CAB;
603 ath_print(common, ATH_DBG_PS,
604 "All PS CAB frames received, back to sleep\n");
605 } else if ((sc->sc_flags & SC_OP_WAIT_FOR_PSPOLL_DATA) &&
606 !is_multicast_ether_addr(hdr->addr1) &&
607 !ieee80211_has_morefrags(hdr->frame_control)) {
608 sc->sc_flags &= ~SC_OP_WAIT_FOR_PSPOLL_DATA;
609 ath_print(common, ATH_DBG_PS,
610 "Going back to sleep after having received "
611 "PS-Poll data (0x%x)\n",
612 sc->sc_flags & (SC_OP_WAIT_FOR_BEACON |
614 SC_OP_WAIT_FOR_PSPOLL_DATA |
615 SC_OP_WAIT_FOR_TX_ACK));
619 static void ath_rx_send_to_mac80211(struct ath_softc *sc, struct sk_buff *skb,
620 struct ieee80211_rx_status *rx_status)
622 struct ieee80211_hdr *hdr;
624 hdr = (struct ieee80211_hdr *)skb->data;
626 /* Send the frame to mac80211 */
627 if (is_multicast_ether_addr(hdr->addr1)) {
630 * Deliver broadcast/multicast frames to all suitable
633 /* TODO: filter based on channel configuration */
634 for (i = 0; i < sc->num_sec_wiphy; i++) {
635 struct ath_wiphy *aphy = sc->sec_wiphy[i];
636 struct sk_buff *nskb;
639 nskb = skb_copy(skb, GFP_ATOMIC);
641 memcpy(IEEE80211_SKB_RXCB(nskb), rx_status,
643 ieee80211_rx(aphy->hw, nskb);
646 memcpy(IEEE80211_SKB_RXCB(skb), rx_status, sizeof(*rx_status));
647 ieee80211_rx(sc->hw, skb);
649 /* Deliver unicast frames based on receiver address */
650 memcpy(IEEE80211_SKB_RXCB(skb), rx_status, sizeof(*rx_status));
651 ieee80211_rx(ath_get_virt_hw(sc, hdr), skb);
655 int ath_rx_tasklet(struct ath_softc *sc, int flush)
657 #define PA2DESC(_sc, _pa) \
658 ((struct ath_desc *)((caddr_t)(_sc)->rx.rxdma.dd_desc + \
659 ((_pa) - (_sc)->rx.rxdma.dd_desc_paddr)))
663 struct sk_buff *skb = NULL, *requeue_skb;
664 struct ieee80211_rx_status rx_status;
665 struct ath_hw *ah = sc->sc_ah;
666 struct ath_common *common = ath9k_hw_common(ah);
667 struct ieee80211_hdr *hdr;
668 int hdrlen, padsize, retval;
669 bool decrypt_error = false;
673 spin_lock_bh(&sc->rx.rxbuflock);
676 /* If handling rx interrupt and flush is in progress => exit */
677 if ((sc->sc_flags & SC_OP_RXFLUSH) && (flush == 0))
680 if (list_empty(&sc->rx.rxbuf)) {
681 sc->rx.rxlink = NULL;
685 bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
689 * Must provide the virtual address of the current
690 * descriptor, the physical address, and the virtual
691 * address of the next descriptor in the h/w chain.
692 * This allows the HAL to look ahead to see if the
693 * hardware is done with a descriptor by checking the
694 * done bit in the following descriptor and the address
695 * of the current descriptor the DMA engine is working
696 * on. All this is necessary because of our use of
697 * a self-linked list to avoid rx overruns.
699 retval = ath9k_hw_rxprocdesc(ah, ds,
701 PA2DESC(sc, ds->ds_link),
703 if (retval == -EINPROGRESS) {
705 struct ath_desc *tds;
707 if (list_is_last(&bf->list, &sc->rx.rxbuf)) {
708 sc->rx.rxlink = NULL;
712 tbf = list_entry(bf->list.next, struct ath_buf, list);
715 * On some hardware the descriptor status words could
716 * get corrupted, including the done bit. Because of
717 * this, check if the next descriptor's done bit is
720 * If the next descriptor's done bit is set, the current
721 * descriptor has been corrupted. Force s/w to discard
722 * this descriptor and continue...
726 retval = ath9k_hw_rxprocdesc(ah, tds, tbf->bf_daddr,
727 PA2DESC(sc, tds->ds_link), 0);
728 if (retval == -EINPROGRESS) {
738 * Synchronize the DMA transfer with CPU before
739 * 1. accessing the frame
740 * 2. requeueing the same buffer to h/w
742 dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
747 * If we're asked to flush receive queue, directly
748 * chain it back at the queue without processing it.
753 if (!ds->ds_rxstat.rs_datalen)
756 /* The status portion of the descriptor could get corrupted. */
757 if (sc->rx.bufsize < ds->ds_rxstat.rs_datalen)
760 if (!ath_rx_prepare(skb, ds, &rx_status, &decrypt_error, sc))
763 /* Ensure we always have an skb to requeue once we are done
764 * processing the current buffer's skb */
765 requeue_skb = ath_rxbuf_alloc(common, sc->rx.bufsize, GFP_ATOMIC);
767 /* If there is no memory we ignore the current RX'd frame,
768 * tell hardware it can give us a new frame using the old
769 * skb and put it at the tail of the sc->rx.rxbuf list for
774 /* Unmap the frame */
775 dma_unmap_single(sc->dev, bf->bf_buf_addr,
779 skb_put(skb, ds->ds_rxstat.rs_datalen);
781 /* see if any padding is done by the hw and remove it */
782 hdr = (struct ieee80211_hdr *)skb->data;
783 hdrlen = ieee80211_get_hdrlen_from_skb(skb);
784 fc = hdr->frame_control;
786 /* The MAC header is padded to have 32-bit boundary if the
787 * packet payload is non-zero. The general calculation for
788 * padsize would take into account odd header lengths:
789 * padsize = (4 - hdrlen % 4) % 4; However, since only
790 * even-length headers are used, padding can only be 0 or 2
791 * bytes and we can optimize this a bit. In addition, we must
792 * not try to remove padding from short control frames that do
793 * not have payload. */
794 padsize = hdrlen & 3;
795 if (padsize && hdrlen >= 24) {
796 memmove(skb->data + padsize, skb->data, hdrlen);
797 skb_pull(skb, padsize);
800 keyix = ds->ds_rxstat.rs_keyix;
802 if (!(keyix == ATH9K_RXKEYIX_INVALID) && !decrypt_error) {
803 rx_status.flag |= RX_FLAG_DECRYPTED;
804 } else if (ieee80211_has_protected(fc)
805 && !decrypt_error && skb->len >= hdrlen + 4) {
806 keyix = skb->data[hdrlen + 3] >> 6;
808 if (test_bit(keyix, sc->keymap))
809 rx_status.flag |= RX_FLAG_DECRYPTED;
811 if (ah->sw_mgmt_crypto &&
812 (rx_status.flag & RX_FLAG_DECRYPTED) &&
813 ieee80211_is_mgmt(fc)) {
814 /* Use software decrypt for management frames. */
815 rx_status.flag &= ~RX_FLAG_DECRYPTED;
818 /* We will now give hardware our shiny new allocated skb */
819 bf->bf_mpdu = requeue_skb;
820 bf->bf_buf_addr = dma_map_single(sc->dev, requeue_skb->data,
823 if (unlikely(dma_mapping_error(sc->dev,
825 dev_kfree_skb_any(requeue_skb);
827 ath_print(common, ATH_DBG_FATAL,
828 "dma_mapping_error() on RX\n");
829 ath_rx_send_to_mac80211(sc, skb, &rx_status);
832 bf->bf_dmacontext = bf->bf_buf_addr;
835 * change the default rx antenna if rx diversity chooses the
836 * other antenna 3 times in a row.
838 if (sc->rx.defant != ds->ds_rxstat.rs_antenna) {
839 if (++sc->rx.rxotherant >= 3)
840 ath_setdefantenna(sc, ds->ds_rxstat.rs_antenna);
842 sc->rx.rxotherant = 0;
845 if (unlikely(sc->sc_flags & (SC_OP_WAIT_FOR_BEACON |
847 SC_OP_WAIT_FOR_PSPOLL_DATA)))
850 ath_rx_send_to_mac80211(sc, skb, &rx_status);
853 list_move_tail(&bf->list, &sc->rx.rxbuf);
854 ath_rx_buf_link(sc, bf);
857 spin_unlock_bh(&sc->rx.rxbuflock);