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1/*2 * Copyright (c) 2008-2011 Atheros Communications Inc.3 *4 * Permission to use, copy, modify, and/or distribute this software for any5 * purpose with or without fee is hereby granted, provided that the above6 * copyright notice and this permission notice appear in all copies.7 *8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.15 */16 17#include <linux/dma-mapping.h>18#include "ath9k.h"19#include "ar9003_mac.h"20 21#define SKB_CB_ATHBUF(__skb)	(*((struct ath_rxbuf **)__skb->cb))22 23static inline bool ath9k_check_auto_sleep(struct ath_softc *sc)24{25	return sc->ps_enabled &&26	       (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_AUTOSLEEP);27}28 29/*30 * Setup and link descriptors.31 *32 * 11N: we can no longer afford to self link the last descriptor.33 * MAC acknowledges BA status as long as it copies frames to host34 * buffer (or rx fifo). This can incorrectly acknowledge packets35 * to a sender if last desc is self-linked.36 */37static void ath_rx_buf_link(struct ath_softc *sc, struct ath_rxbuf *bf,38			    bool flush)39{40	struct ath_hw *ah = sc->sc_ah;41	struct ath_common *common = ath9k_hw_common(ah);42	struct ath_desc *ds;43	struct sk_buff *skb;44 45	ds = bf->bf_desc;46	ds->ds_link = 0; /* link to null */47	ds->ds_data = bf->bf_buf_addr;48 49	/* virtual addr of the beginning of the buffer. */50	skb = bf->bf_mpdu;51	BUG_ON(skb == NULL);52	ds->ds_vdata = skb->data;53 54	/*55	 * setup rx descriptors. The rx_bufsize here tells the hardware56	 * how much data it can DMA to us and that we are prepared57	 * to process58	 */59	ath9k_hw_setuprxdesc(ah, ds,60			     common->rx_bufsize,61			     0);62 63	if (sc->rx.rxlink)64		*sc->rx.rxlink = bf->bf_daddr;65	else if (!flush)66		ath9k_hw_putrxbuf(ah, bf->bf_daddr);67 68	sc->rx.rxlink = &ds->ds_link;69}70 71static void ath_rx_buf_relink(struct ath_softc *sc, struct ath_rxbuf *bf,72			      bool flush)73{74	if (sc->rx.buf_hold)75		ath_rx_buf_link(sc, sc->rx.buf_hold, flush);76 77	sc->rx.buf_hold = bf;78}79 80static void ath_setdefantenna(struct ath_softc *sc, u32 antenna)81{82	/* XXX block beacon interrupts */83	ath9k_hw_setantenna(sc->sc_ah, antenna);84	sc->rx.defant = antenna;85	sc->rx.rxotherant = 0;86}87 88static void ath_opmode_init(struct ath_softc *sc)89{90	struct ath_hw *ah = sc->sc_ah;91	struct ath_common *common = ath9k_hw_common(ah);92 93	u32 rfilt, mfilt[2];94 95	/* configure rx filter */96	rfilt = ath_calcrxfilter(sc);97	ath9k_hw_setrxfilter(ah, rfilt);98 99	/* configure bssid mask */100	ath_hw_setbssidmask(common);101 102	/* configure operational mode */103	ath9k_hw_setopmode(ah);104 105	/* calculate and install multicast filter */106	mfilt[0] = mfilt[1] = ~0;107	ath9k_hw_setmcastfilter(ah, mfilt[0], mfilt[1]);108}109 110static bool ath_rx_edma_buf_link(struct ath_softc *sc,111				 enum ath9k_rx_qtype qtype)112{113	struct ath_hw *ah = sc->sc_ah;114	struct ath_rx_edma *rx_edma;115	struct sk_buff *skb;116	struct ath_rxbuf *bf;117 118	rx_edma = &sc->rx.rx_edma[qtype];119	if (skb_queue_len(&rx_edma->rx_fifo) >= rx_edma->rx_fifo_hwsize)120		return false;121 122	bf = list_first_entry(&sc->rx.rxbuf, struct ath_rxbuf, list);123	list_del_init(&bf->list);124 125	skb = bf->bf_mpdu;126 127	memset(skb->data, 0, ah->caps.rx_status_len);128	dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,129				ah->caps.rx_status_len, DMA_TO_DEVICE);130 131	SKB_CB_ATHBUF(skb) = bf;132	ath9k_hw_addrxbuf_edma(ah, bf->bf_buf_addr, qtype);133	__skb_queue_tail(&rx_edma->rx_fifo, skb);134 135	return true;136}137 138static void ath_rx_addbuffer_edma(struct ath_softc *sc,139				  enum ath9k_rx_qtype qtype)140{141	struct ath_common *common = ath9k_hw_common(sc->sc_ah);142	struct ath_rxbuf *bf, *tbf;143 144	if (list_empty(&sc->rx.rxbuf)) {145		ath_dbg(common, QUEUE, "No free rx buf available\n");146		return;147	}148 149	list_for_each_entry_safe(bf, tbf, &sc->rx.rxbuf, list)150		if (!ath_rx_edma_buf_link(sc, qtype))151			break;152 153}154 155static void ath_rx_remove_buffer(struct ath_softc *sc,156				 enum ath9k_rx_qtype qtype)157{158	struct ath_rxbuf *bf;159	struct ath_rx_edma *rx_edma;160	struct sk_buff *skb;161 162	rx_edma = &sc->rx.rx_edma[qtype];163 164	while ((skb = __skb_dequeue(&rx_edma->rx_fifo)) != NULL) {165		bf = SKB_CB_ATHBUF(skb);166		BUG_ON(!bf);167		list_add_tail(&bf->list, &sc->rx.rxbuf);168	}169}170 171static void ath_rx_edma_cleanup(struct ath_softc *sc)172{173	struct ath_hw *ah = sc->sc_ah;174	struct ath_common *common = ath9k_hw_common(ah);175	struct ath_rxbuf *bf;176 177	ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_LP);178	ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_HP);179 180	list_for_each_entry(bf, &sc->rx.rxbuf, list) {181		if (bf->bf_mpdu) {182			dma_unmap_single(sc->dev, bf->bf_buf_addr,183					common->rx_bufsize,184					DMA_BIDIRECTIONAL);185			dev_kfree_skb_any(bf->bf_mpdu);186			bf->bf_buf_addr = 0;187			bf->bf_mpdu = NULL;188		}189	}190}191 192static void ath_rx_edma_init_queue(struct ath_rx_edma *rx_edma, int size)193{194	__skb_queue_head_init(&rx_edma->rx_fifo);195	rx_edma->rx_fifo_hwsize = size;196}197 198static int ath_rx_edma_init(struct ath_softc *sc, int nbufs)199{200	struct ath_common *common = ath9k_hw_common(sc->sc_ah);201	struct ath_hw *ah = sc->sc_ah;202	struct sk_buff *skb;203	struct ath_rxbuf *bf;204	int error = 0, i;205	u32 size;206 207	ath9k_hw_set_rx_bufsize(ah, common->rx_bufsize -208				    ah->caps.rx_status_len);209 210	ath_rx_edma_init_queue(&sc->rx.rx_edma[ATH9K_RX_QUEUE_LP],211			       ah->caps.rx_lp_qdepth);212	ath_rx_edma_init_queue(&sc->rx.rx_edma[ATH9K_RX_QUEUE_HP],213			       ah->caps.rx_hp_qdepth);214 215	size = sizeof(struct ath_rxbuf) * nbufs;216	bf = devm_kzalloc(sc->dev, size, GFP_KERNEL);217	if (!bf)218		return -ENOMEM;219 220	INIT_LIST_HEAD(&sc->rx.rxbuf);221 222	for (i = 0; i < nbufs; i++, bf++) {223		skb = ath_rxbuf_alloc(common, common->rx_bufsize, GFP_KERNEL);224		if (!skb) {225			error = -ENOMEM;226			goto rx_init_fail;227		}228 229		memset(skb->data, 0, common->rx_bufsize);230		bf->bf_mpdu = skb;231 232		bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,233						 common->rx_bufsize,234						 DMA_BIDIRECTIONAL);235		if (unlikely(dma_mapping_error(sc->dev,236						bf->bf_buf_addr))) {237				dev_kfree_skb_any(skb);238				bf->bf_mpdu = NULL;239				bf->bf_buf_addr = 0;240				ath_err(common,241					"dma_mapping_error() on RX init\n");242				error = -ENOMEM;243				goto rx_init_fail;244		}245 246		list_add_tail(&bf->list, &sc->rx.rxbuf);247	}248 249	return 0;250 251rx_init_fail:252	ath_rx_edma_cleanup(sc);253	return error;254}255 256static void ath_edma_start_recv(struct ath_softc *sc)257{258	ath9k_hw_rxena(sc->sc_ah);259	ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_HP);260	ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_LP);261	ath_opmode_init(sc);262	ath9k_hw_startpcureceive(sc->sc_ah, sc->cur_chan->offchannel);263}264 265static void ath_edma_stop_recv(struct ath_softc *sc)266{267	ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_HP);268	ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_LP);269}270 271int ath_rx_init(struct ath_softc *sc, int nbufs)272{273	struct ath_common *common = ath9k_hw_common(sc->sc_ah);274	struct sk_buff *skb;275	struct ath_rxbuf *bf;276	int error = 0;277 278	spin_lock_init(&sc->sc_pcu_lock);279 280	common->rx_bufsize = IEEE80211_MAX_MPDU_LEN / 2 +281			     sc->sc_ah->caps.rx_status_len;282 283	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)284		return ath_rx_edma_init(sc, nbufs);285 286	ath_dbg(common, CONFIG, "cachelsz %u rxbufsize %u\n",287		common->cachelsz, common->rx_bufsize);288 289	/* Initialize rx descriptors */290 291	error = ath_descdma_setup(sc, &sc->rx.rxdma, &sc->rx.rxbuf,292				  "rx", nbufs, 1, 0);293	if (error != 0) {294		ath_err(common,295			"failed to allocate rx descriptors: %d\n",296			error);297		goto err;298	}299 300	list_for_each_entry(bf, &sc->rx.rxbuf, list) {301		skb = ath_rxbuf_alloc(common, common->rx_bufsize,302				      GFP_KERNEL);303		if (skb == NULL) {304			error = -ENOMEM;305			goto err;306		}307 308		bf->bf_mpdu = skb;309		bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,310						 common->rx_bufsize,311						 DMA_FROM_DEVICE);312		if (unlikely(dma_mapping_error(sc->dev,313					       bf->bf_buf_addr))) {314			dev_kfree_skb_any(skb);315			bf->bf_mpdu = NULL;316			bf->bf_buf_addr = 0;317			ath_err(common,318				"dma_mapping_error() on RX init\n");319			error = -ENOMEM;320			goto err;321		}322	}323	sc->rx.rxlink = NULL;324err:325	if (error)326		ath_rx_cleanup(sc);327 328	return error;329}330 331void ath_rx_cleanup(struct ath_softc *sc)332{333	struct ath_hw *ah = sc->sc_ah;334	struct ath_common *common = ath9k_hw_common(ah);335	struct sk_buff *skb;336	struct ath_rxbuf *bf;337 338	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {339		ath_rx_edma_cleanup(sc);340		return;341	}342 343	list_for_each_entry(bf, &sc->rx.rxbuf, list) {344		skb = bf->bf_mpdu;345		if (skb) {346			dma_unmap_single(sc->dev, bf->bf_buf_addr,347					 common->rx_bufsize,348					 DMA_FROM_DEVICE);349			dev_kfree_skb(skb);350			bf->bf_buf_addr = 0;351			bf->bf_mpdu = NULL;352		}353	}354}355 356/*357 * Calculate the receive filter according to the358 * operating mode and state:359 *360 * o always accept unicast, broadcast, and multicast traffic361 * o maintain current state of phy error reception (the hal362 *   may enable phy error frames for noise immunity work)363 * o probe request frames are accepted only when operating in364 *   hostap, adhoc, or monitor modes365 * o enable promiscuous mode according to the interface state366 * o accept beacons:367 *   - when operating in adhoc mode so the 802.11 layer creates368 *     node table entries for peers,369 *   - when operating in station mode for collecting rssi data when370 *     the station is otherwise quiet, or371 *   - when operating as a repeater so we see repeater-sta beacons372 *   - when scanning373 */374 375u32 ath_calcrxfilter(struct ath_softc *sc)376{377	struct ath_common *common = ath9k_hw_common(sc->sc_ah);378	u32 rfilt;379 380	if (IS_ENABLED(CONFIG_ATH9K_TX99))381		return 0;382 383	rfilt = ATH9K_RX_FILTER_UCAST | ATH9K_RX_FILTER_BCAST384		| ATH9K_RX_FILTER_MCAST;385 386	/* if operating on a DFS channel, enable radar pulse detection */387	if (sc->hw->conf.radar_enabled)388		rfilt |= ATH9K_RX_FILTER_PHYRADAR | ATH9K_RX_FILTER_PHYERR;389 390	spin_lock_bh(&sc->chan_lock);391 392	if (sc->cur_chan->rxfilter & FIF_PROBE_REQ)393		rfilt |= ATH9K_RX_FILTER_PROBEREQ;394 395	if (sc->sc_ah->is_monitoring)396		rfilt |= ATH9K_RX_FILTER_PROM;397 398	if ((sc->cur_chan->rxfilter & FIF_CONTROL) ||399	    sc->sc_ah->dynack.enabled)400		rfilt |= ATH9K_RX_FILTER_CONTROL;401 402	if ((sc->sc_ah->opmode == NL80211_IFTYPE_STATION) &&403	    (sc->cur_chan->nvifs <= 1) &&404	    !(sc->cur_chan->rxfilter & FIF_BCN_PRBRESP_PROMISC))405		rfilt |= ATH9K_RX_FILTER_MYBEACON;406	else if (sc->sc_ah->opmode != NL80211_IFTYPE_OCB)407		rfilt |= ATH9K_RX_FILTER_BEACON;408 409	if ((sc->sc_ah->opmode == NL80211_IFTYPE_AP) ||410	    (sc->cur_chan->rxfilter & FIF_PSPOLL))411		rfilt |= ATH9K_RX_FILTER_PSPOLL;412 413	if (sc->cur_chandef.width != NL80211_CHAN_WIDTH_20_NOHT)414		rfilt |= ATH9K_RX_FILTER_COMP_BAR;415 416	if (sc->cur_chan->nvifs > 1 ||417	    (sc->cur_chan->rxfilter & (FIF_OTHER_BSS | FIF_MCAST_ACTION))) {418		/* This is needed for older chips */419		if (sc->sc_ah->hw_version.macVersion <= AR_SREV_VERSION_9160)420			rfilt |= ATH9K_RX_FILTER_PROM;421		rfilt |= ATH9K_RX_FILTER_MCAST_BCAST_ALL;422	}423 424	if (AR_SREV_9550(sc->sc_ah) || AR_SREV_9531(sc->sc_ah) ||425	    AR_SREV_9561(sc->sc_ah))426		rfilt |= ATH9K_RX_FILTER_4ADDRESS;427 428	if (AR_SREV_9462(sc->sc_ah) || AR_SREV_9565(sc->sc_ah))429		rfilt |= ATH9K_RX_FILTER_CONTROL_WRAPPER;430 431	if (ath9k_is_chanctx_enabled() &&432	    test_bit(ATH_OP_SCANNING, &common->op_flags))433		rfilt |= ATH9K_RX_FILTER_BEACON;434 435	spin_unlock_bh(&sc->chan_lock);436 437	return rfilt;438 439}440 441void ath_startrecv(struct ath_softc *sc)442{443	struct ath_hw *ah = sc->sc_ah;444	struct ath_rxbuf *bf, *tbf;445 446	if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {447		ath_edma_start_recv(sc);448		return;449	}450 451	if (list_empty(&sc->rx.rxbuf))452		goto start_recv;453 454	sc->rx.buf_hold = NULL;455	sc->rx.rxlink = NULL;456	list_for_each_entry_safe(bf, tbf, &sc->rx.rxbuf, list) {457		ath_rx_buf_link(sc, bf, false);458	}459 460	/* We could have deleted elements so the list may be empty now */461	if (list_empty(&sc->rx.rxbuf))462		goto start_recv;463 464	bf = list_first_entry(&sc->rx.rxbuf, struct ath_rxbuf, list);465	ath9k_hw_putrxbuf(ah, bf->bf_daddr);466	ath9k_hw_rxena(ah);467 468start_recv:469	ath_opmode_init(sc);470	ath9k_hw_startpcureceive(ah, sc->cur_chan->offchannel);471}472 473static void ath_flushrecv(struct ath_softc *sc)474{475	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)476		ath_rx_tasklet(sc, 1, true);477	ath_rx_tasklet(sc, 1, false);478}479 480bool ath_stoprecv(struct ath_softc *sc)481{482	struct ath_hw *ah = sc->sc_ah;483	bool stopped, reset = false;484 485	ath9k_hw_abortpcurecv(ah);486	ath9k_hw_setrxfilter(ah, 0);487	stopped = ath9k_hw_stopdmarecv(ah, &reset);488 489	ath_flushrecv(sc);490 491	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)492		ath_edma_stop_recv(sc);493	else494		sc->rx.rxlink = NULL;495 496	if (!(ah->ah_flags & AH_UNPLUGGED) &&497	    unlikely(!stopped)) {498		ath_dbg(ath9k_hw_common(sc->sc_ah), RESET,499			"Failed to stop Rx DMA\n");500		RESET_STAT_INC(sc, RESET_RX_DMA_ERROR);501	}502	return stopped && !reset;503}504 505static bool ath_beacon_dtim_pending_cab(struct sk_buff *skb)506{507	/* Check whether the Beacon frame has DTIM indicating buffered bc/mc */508	struct ieee80211_mgmt *mgmt;509	u8 *pos, *end, id, elen;510	struct ieee80211_tim_ie *tim;511 512	mgmt = (struct ieee80211_mgmt *)skb->data;513	pos = mgmt->u.beacon.variable;514	end = skb->data + skb->len;515 516	while (pos + 2 < end) {517		id = *pos++;518		elen = *pos++;519		if (pos + elen > end)520			break;521 522		if (id == WLAN_EID_TIM) {523			if (elen < sizeof(*tim))524				break;525			tim = (struct ieee80211_tim_ie *) pos;526			if (tim->dtim_count != 0)527				break;528			return tim->bitmap_ctrl & 0x01;529		}530 531		pos += elen;532	}533 534	return false;535}536 537static void ath_rx_ps_beacon(struct ath_softc *sc, struct sk_buff *skb)538{539	struct ath_common *common = ath9k_hw_common(sc->sc_ah);540	bool skip_beacon = false;541 542	if (skb->len < 24 + 8 + 2 + 2)543		return;544 545	sc->ps_flags &= ~PS_WAIT_FOR_BEACON;546 547	if (sc->ps_flags & PS_BEACON_SYNC) {548		sc->ps_flags &= ~PS_BEACON_SYNC;549		ath_dbg(common, PS,550			"Reconfigure beacon timers based on synchronized timestamp\n");551 552#ifdef CONFIG_ATH9K_CHANNEL_CONTEXT553		if (ath9k_is_chanctx_enabled()) {554			if (sc->cur_chan == &sc->offchannel.chan)555				skip_beacon = true;556		}557#endif558 559		if (!skip_beacon &&560		    !(WARN_ON_ONCE(sc->cur_chan->beacon.beacon_interval == 0)))561			ath9k_set_beacon(sc);562 563		ath9k_p2p_beacon_sync(sc);564	}565 566	if (ath_beacon_dtim_pending_cab(skb)) {567		/*568		 * Remain awake waiting for buffered broadcast/multicast569		 * frames. If the last broadcast/multicast frame is not570		 * received properly, the next beacon frame will work as571		 * a backup trigger for returning into NETWORK SLEEP state,572		 * so we are waiting for it as well.573		 */574		ath_dbg(common, PS,575			"Received DTIM beacon indicating buffered broadcast/multicast frame(s)\n");576		sc->ps_flags |= PS_WAIT_FOR_CAB | PS_WAIT_FOR_BEACON;577		return;578	}579 580	if (sc->ps_flags & PS_WAIT_FOR_CAB) {581		/*582		 * This can happen if a broadcast frame is dropped or the AP583		 * fails to send a frame indicating that all CAB frames have584		 * been delivered.585		 */586		sc->ps_flags &= ~PS_WAIT_FOR_CAB;587		ath_dbg(common, PS, "PS wait for CAB frames timed out\n");588	}589}590 591static void ath_rx_ps(struct ath_softc *sc, struct sk_buff *skb, bool mybeacon)592{593	struct ieee80211_hdr *hdr;594	struct ath_common *common = ath9k_hw_common(sc->sc_ah);595 596	hdr = (struct ieee80211_hdr *)skb->data;597 598	/* Process Beacon and CAB receive in PS state */599	if (((sc->ps_flags & PS_WAIT_FOR_BEACON) || ath9k_check_auto_sleep(sc))600	    && mybeacon) {601		ath_rx_ps_beacon(sc, skb);602	} else if ((sc->ps_flags & PS_WAIT_FOR_CAB) &&603		   (ieee80211_is_data(hdr->frame_control) ||604		    ieee80211_is_action(hdr->frame_control)) &&605		   is_multicast_ether_addr(hdr->addr1) &&606		   !ieee80211_has_moredata(hdr->frame_control)) {607		/*608		 * No more broadcast/multicast frames to be received at this609		 * point.610		 */611		sc->ps_flags &= ~(PS_WAIT_FOR_CAB | PS_WAIT_FOR_BEACON);612		ath_dbg(common, PS,613			"All PS CAB frames received, back to sleep\n");614	} else if ((sc->ps_flags & PS_WAIT_FOR_PSPOLL_DATA) &&615		   !is_multicast_ether_addr(hdr->addr1) &&616		   !ieee80211_has_morefrags(hdr->frame_control)) {617		sc->ps_flags &= ~PS_WAIT_FOR_PSPOLL_DATA;618		ath_dbg(common, PS,619			"Going back to sleep after having received PS-Poll data (0x%lx)\n",620			sc->ps_flags & (PS_WAIT_FOR_BEACON |621					PS_WAIT_FOR_CAB |622					PS_WAIT_FOR_PSPOLL_DATA |623					PS_WAIT_FOR_TX_ACK));624	}625}626 627static bool ath_edma_get_buffers(struct ath_softc *sc,628				 enum ath9k_rx_qtype qtype,629				 struct ath_rx_status *rs,630				 struct ath_rxbuf **dest)631{632	struct ath_rx_edma *rx_edma = &sc->rx.rx_edma[qtype];633	struct ath_hw *ah = sc->sc_ah;634	struct ath_common *common = ath9k_hw_common(ah);635	struct sk_buff *skb;636	struct ath_rxbuf *bf;637	int ret;638 639	skb = skb_peek(&rx_edma->rx_fifo);640	if (!skb)641		return false;642 643	bf = SKB_CB_ATHBUF(skb);644	BUG_ON(!bf);645 646	dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,647				common->rx_bufsize, DMA_FROM_DEVICE);648 649	ret = ath9k_hw_process_rxdesc_edma(ah, rs, skb->data);650	if (ret == -EINPROGRESS) {651		/*let device gain the buffer again*/652		dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,653				common->rx_bufsize, DMA_FROM_DEVICE);654		return false;655	}656 657	__skb_unlink(skb, &rx_edma->rx_fifo);658	if (ret == -EINVAL) {659		/* corrupt descriptor, skip this one and the following one */660		list_add_tail(&bf->list, &sc->rx.rxbuf);661		ath_rx_edma_buf_link(sc, qtype);662 663		skb = skb_peek(&rx_edma->rx_fifo);664		if (skb) {665			bf = SKB_CB_ATHBUF(skb);666			BUG_ON(!bf);667 668			__skb_unlink(skb, &rx_edma->rx_fifo);669			list_add_tail(&bf->list, &sc->rx.rxbuf);670			ath_rx_edma_buf_link(sc, qtype);671		}672 673		bf = NULL;674	}675 676	*dest = bf;677	return true;678}679 680static struct ath_rxbuf *ath_edma_get_next_rx_buf(struct ath_softc *sc,681						struct ath_rx_status *rs,682						enum ath9k_rx_qtype qtype)683{684	struct ath_rxbuf *bf = NULL;685 686	while (ath_edma_get_buffers(sc, qtype, rs, &bf)) {687		if (!bf)688			continue;689 690		return bf;691	}692	return NULL;693}694 695static struct ath_rxbuf *ath_get_next_rx_buf(struct ath_softc *sc,696					   struct ath_rx_status *rs)697{698	struct ath_hw *ah = sc->sc_ah;699	struct ath_common *common = ath9k_hw_common(ah);700	struct ath_desc *ds;701	struct ath_rxbuf *bf;702	int ret;703 704	if (list_empty(&sc->rx.rxbuf)) {705		sc->rx.rxlink = NULL;706		return NULL;707	}708 709	bf = list_first_entry(&sc->rx.rxbuf, struct ath_rxbuf, list);710	if (bf == sc->rx.buf_hold)711		return NULL;712 713	ds = bf->bf_desc;714 715	/*716	 * Must provide the virtual address of the current717	 * descriptor, the physical address, and the virtual718	 * address of the next descriptor in the h/w chain.719	 * This allows the HAL to look ahead to see if the720	 * hardware is done with a descriptor by checking the721	 * done bit in the following descriptor and the address722	 * of the current descriptor the DMA engine is working723	 * on.  All this is necessary because of our use of724	 * a self-linked list to avoid rx overruns.725	 */726	ret = ath9k_hw_rxprocdesc(ah, ds, rs);727	if (ret == -EINPROGRESS) {728		struct ath_rx_status trs;729		struct ath_rxbuf *tbf;730		struct ath_desc *tds;731 732		memset(&trs, 0, sizeof(trs));733		if (list_is_last(&bf->list, &sc->rx.rxbuf)) {734			sc->rx.rxlink = NULL;735			return NULL;736		}737 738		tbf = list_entry(bf->list.next, struct ath_rxbuf, list);739 740		/*741		 * On some hardware the descriptor status words could742		 * get corrupted, including the done bit. Because of743		 * this, check if the next descriptor's done bit is744		 * set or not.745		 *746		 * If the next descriptor's done bit is set, the current747		 * descriptor has been corrupted. Force s/w to discard748		 * this descriptor and continue...749		 */750 751		tds = tbf->bf_desc;752		ret = ath9k_hw_rxprocdesc(ah, tds, &trs);753		if (ret == -EINPROGRESS)754			return NULL;755 756		/*757		 * Re-check previous descriptor, in case it has been filled758		 * in the mean time.759		 */760		ret = ath9k_hw_rxprocdesc(ah, ds, rs);761		if (ret == -EINPROGRESS) {762			/*763			 * mark descriptor as zero-length and set the 'more'764			 * flag to ensure that both buffers get discarded765			 */766			rs->rs_datalen = 0;767			rs->rs_more = true;768		}769	}770 771	list_del(&bf->list);772	if (!bf->bf_mpdu)773		return bf;774 775	/*776	 * Synchronize the DMA transfer with CPU before777	 * 1. accessing the frame778	 * 2. requeueing the same buffer to h/w779	 */780	dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,781			common->rx_bufsize,782			DMA_FROM_DEVICE);783 784	return bf;785}786 787static void ath9k_process_tsf(struct ath_rx_status *rs,788			      struct ieee80211_rx_status *rxs,789			      u64 tsf)790{791	u32 tsf_lower = tsf & 0xffffffff;792 793	rxs->mactime = (tsf & ~0xffffffffULL) | rs->rs_tstamp;794	if (rs->rs_tstamp > tsf_lower &&795	    unlikely(rs->rs_tstamp - tsf_lower > 0x10000000))796		rxs->mactime -= 0x100000000ULL;797 798	if (rs->rs_tstamp < tsf_lower &&799	    unlikely(tsf_lower - rs->rs_tstamp > 0x10000000))800		rxs->mactime += 0x100000000ULL;801}802 803/*804 * For Decrypt or Demic errors, we only mark packet status here and always push805 * up the frame up to let mac80211 handle the actual error case, be it no806 * decryption key or real decryption error. This let us keep statistics there.807 */808static int ath9k_rx_skb_preprocess(struct ath_softc *sc,809				   struct sk_buff *skb,810				   struct ath_rx_status *rx_stats,811				   struct ieee80211_rx_status *rx_status,812				   bool *decrypt_error, u64 tsf)813{814	struct ieee80211_hw *hw = sc->hw;815	struct ath_hw *ah = sc->sc_ah;816	struct ath_common *common = ath9k_hw_common(ah);817	struct ieee80211_hdr *hdr;818	bool discard_current = sc->rx.discard_next;819	bool is_phyerr;820 821	/*822	 * Discard corrupt descriptors which are marked in823	 * ath_get_next_rx_buf().824	 */825	if (discard_current)826		goto corrupt;827 828	sc->rx.discard_next = false;829 830	/*831	 * Discard zero-length packets and packets smaller than an ACK832	 * which are not PHY_ERROR (short radar pulses have a length of 3)833	 */834	is_phyerr = rx_stats->rs_status & ATH9K_RXERR_PHY;835	if (!rx_stats->rs_datalen ||836	    (rx_stats->rs_datalen < 10 && !is_phyerr)) {837		RX_STAT_INC(sc, rx_len_err);838		goto corrupt;839	}840 841	/*842	 * rs_status follows rs_datalen so if rs_datalen is too large843	 * we can take a hint that hardware corrupted it, so ignore844	 * those frames.845	 */846	if (rx_stats->rs_datalen > (common->rx_bufsize - ah->caps.rx_status_len)) {847		RX_STAT_INC(sc, rx_len_err);848		goto corrupt;849	}850 851	/* Only use status info from the last fragment */852	if (rx_stats->rs_more)853		return 0;854 855	/*856	 * Return immediately if the RX descriptor has been marked857	 * as corrupt based on the various error bits.858	 *859	 * This is different from the other corrupt descriptor860	 * condition handled above.861	 */862	if (rx_stats->rs_status & ATH9K_RXERR_CORRUPT_DESC)863		goto corrupt;864 865	hdr = (struct ieee80211_hdr *) (skb->data + ah->caps.rx_status_len);866 867	ath9k_process_tsf(rx_stats, rx_status, tsf);868	ath_debug_stat_rx(sc, rx_stats);869 870	/*871	 * Process PHY errors and return so that the packet872	 * can be dropped.873	 */874	if (rx_stats->rs_status & ATH9K_RXERR_PHY) {875		/*876		 * DFS and spectral are mutually exclusive877		 *878		 * Since some chips use PHYERR_RADAR as indication for both, we879		 * need to double check which feature is enabled to prevent880		 * feeding spectral or dfs-detector with wrong frames.881		 */882		if (hw->conf.radar_enabled) {883			ath9k_dfs_process_phyerr(sc, hdr, rx_stats,884						 rx_status->mactime);885		} else if (sc->spec_priv.spectral_mode != SPECTRAL_DISABLED &&886			   ath_cmn_process_fft(&sc->spec_priv, hdr, rx_stats,887					       rx_status->mactime)) {888			RX_STAT_INC(sc, rx_spectral);889		}890		return -EINVAL;891	}892 893	/*894	 * everything but the rate is checked here, the rate check is done895	 * separately to avoid doing two lookups for a rate for each frame.896	 */897	spin_lock_bh(&sc->chan_lock);898	if (!ath9k_cmn_rx_accept(common, hdr, rx_status, rx_stats, decrypt_error,899				 sc->cur_chan->rxfilter)) {900		spin_unlock_bh(&sc->chan_lock);901		return -EINVAL;902	}903	spin_unlock_bh(&sc->chan_lock);904 905	if (ath_is_mybeacon(common, hdr)) {906		RX_STAT_INC(sc, rx_beacons);907		rx_stats->is_mybeacon = true;908	}909 910	/*911	 * This shouldn't happen, but have a safety check anyway.912	 */913	if (WARN_ON(!ah->curchan))914		return -EINVAL;915 916	if (ath9k_cmn_process_rate(common, hw, rx_stats, rx_status)) {917		/*918		 * No valid hardware bitrate found -- we should not get here919		 * because hardware has already validated this frame as OK.920		 */921		ath_dbg(common, ANY, "unsupported hw bitrate detected 0x%02x using 1 Mbit\n",922			rx_stats->rs_rate);923		RX_STAT_INC(sc, rx_rate_err);924		return -EINVAL;925	}926 927	if (ath9k_is_chanctx_enabled()) {928		if (rx_stats->is_mybeacon)929			ath_chanctx_beacon_recv_ev(sc,930					   ATH_CHANCTX_EVENT_BEACON_RECEIVED);931	}932 933	ath9k_cmn_process_rssi(common, hw, rx_stats, rx_status);934 935	rx_status->band = ah->curchan->chan->band;936	rx_status->freq = ah->curchan->chan->center_freq;937	rx_status->antenna = rx_stats->rs_antenna;938	rx_status->flag |= RX_FLAG_MACTIME_END;939 940#ifdef CONFIG_ATH9K_BTCOEX_SUPPORT941	if (ieee80211_is_data_present(hdr->frame_control) &&942	    !ieee80211_is_qos_nullfunc(hdr->frame_control))943		sc->rx.num_pkts++;944#endif945 946	return 0;947 948corrupt:949	sc->rx.discard_next = rx_stats->rs_more;950	return -EINVAL;951}952 953/*954 * Run the LNA combining algorithm only in these cases:955 *956 * Standalone WLAN cards with both LNA/Antenna diversity957 * enabled in the EEPROM.958 *959 * WLAN+BT cards which are in the supported card list960 * in ath_pci_id_table and the user has loaded the961 * driver with "bt_ant_diversity" set to true.962 */963static void ath9k_antenna_check(struct ath_softc *sc,964				struct ath_rx_status *rs)965{966	struct ath_hw *ah = sc->sc_ah;967	struct ath9k_hw_capabilities *pCap = &ah->caps;968	struct ath_common *common = ath9k_hw_common(ah);969 970	if (!(ah->caps.hw_caps & ATH9K_HW_CAP_ANT_DIV_COMB))971		return;972 973	/*974	 * Change the default rx antenna if rx diversity975	 * chooses the other antenna 3 times in a row.976	 */977	if (sc->rx.defant != rs->rs_antenna) {978		if (++sc->rx.rxotherant >= 3)979			ath_setdefantenna(sc, rs->rs_antenna);980	} else {981		sc->rx.rxotherant = 0;982	}983 984	if (pCap->hw_caps & ATH9K_HW_CAP_BT_ANT_DIV) {985		if (common->bt_ant_diversity)986			ath_ant_comb_scan(sc, rs);987	} else {988		ath_ant_comb_scan(sc, rs);989	}990}991 992static void ath9k_apply_ampdu_details(struct ath_softc *sc,993	struct ath_rx_status *rs, struct ieee80211_rx_status *rxs)994{995	if (rs->rs_isaggr) {996		rxs->flag |= RX_FLAG_AMPDU_DETAILS | RX_FLAG_AMPDU_LAST_KNOWN;997 998		rxs->ampdu_reference = sc->rx.ampdu_ref;999 1000		if (!rs->rs_moreaggr) {1001			rxs->flag |= RX_FLAG_AMPDU_IS_LAST;1002			sc->rx.ampdu_ref++;1003		}1004 1005		if (rs->rs_flags & ATH9K_RX_DELIM_CRC_PRE)1006			rxs->flag |= RX_FLAG_AMPDU_DELIM_CRC_ERROR;1007	}1008}1009 1010static void ath_rx_count_airtime(struct ath_softc *sc,1011				 struct ath_rx_status *rs,1012				 struct sk_buff *skb)1013{1014	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;1015	struct ath_hw *ah = sc->sc_ah;1016	struct ath_common *common = ath9k_hw_common(ah);1017	struct ieee80211_sta *sta;1018	struct ieee80211_rx_status *rxs;1019	const struct ieee80211_rate *rate;1020	bool is_sgi, is_40, is_sp;1021	int phy;1022	u16 len = rs->rs_datalen;1023	u32 airtime = 0;1024	u8 tidno;1025 1026	if (!ieee80211_is_data(hdr->frame_control))1027		return;1028 1029	rcu_read_lock();1030 1031	sta = ieee80211_find_sta_by_ifaddr(sc->hw, hdr->addr2, NULL);1032	if (!sta)1033		goto exit;1034	tidno = skb->priority & IEEE80211_QOS_CTL_TID_MASK;1035 1036	rxs = IEEE80211_SKB_RXCB(skb);1037 1038	is_sgi = !!(rxs->enc_flags & RX_ENC_FLAG_SHORT_GI);1039	is_40 = !!(rxs->bw == RATE_INFO_BW_40);1040	is_sp = !!(rxs->enc_flags & RX_ENC_FLAG_SHORTPRE);1041 1042	if (!!(rxs->encoding == RX_ENC_HT)) {1043		/* MCS rates */1044 1045		airtime += ath_pkt_duration(sc, rxs->rate_idx, len,1046					is_40, is_sgi, is_sp);1047	} else {1048 1049		phy = IS_CCK_RATE(rs->rs_rate) ? WLAN_RC_PHY_CCK : WLAN_RC_PHY_OFDM;1050		rate = &common->sbands[rxs->band].bitrates[rxs->rate_idx];1051		airtime += ath9k_hw_computetxtime(ah, phy, rate->bitrate * 100,1052						len, rxs->rate_idx, is_sp);1053	}1054 1055	ieee80211_sta_register_airtime(sta, tidno, 0, airtime);1056exit:1057	rcu_read_unlock();1058}1059 1060int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)1061{1062	struct ath_rxbuf *bf;1063	struct sk_buff *skb = NULL, *requeue_skb, *hdr_skb;1064	struct ieee80211_rx_status *rxs;1065	struct ath_hw *ah = sc->sc_ah;1066	struct ath_common *common = ath9k_hw_common(ah);1067	struct ieee80211_hw *hw = sc->hw;1068	int retval;1069	struct ath_rx_status rs;1070	enum ath9k_rx_qtype qtype;1071	bool edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);1072	int dma_type;1073	u64 tsf = 0;1074	unsigned long flags;1075	dma_addr_t new_buf_addr;1076	unsigned int budget = 512;1077	struct ieee80211_hdr *hdr;1078 1079	if (edma)1080		dma_type = DMA_BIDIRECTIONAL;1081	else1082		dma_type = DMA_FROM_DEVICE;1083 1084	qtype = hp ? ATH9K_RX_QUEUE_HP : ATH9K_RX_QUEUE_LP;1085 1086	tsf = ath9k_hw_gettsf64(ah);1087 1088	do {1089		bool decrypt_error = false;1090 1091		memset(&rs, 0, sizeof(rs));1092		if (edma)1093			bf = ath_edma_get_next_rx_buf(sc, &rs, qtype);1094		else1095			bf = ath_get_next_rx_buf(sc, &rs);1096 1097		if (!bf)1098			break;1099 1100		skb = bf->bf_mpdu;1101		if (!skb)1102			continue;1103 1104		/*1105		 * Take frame header from the first fragment and RX status from1106		 * the last one.1107		 */1108		if (sc->rx.frag)1109			hdr_skb = sc->rx.frag;1110		else1111			hdr_skb = skb;1112 1113		rxs = IEEE80211_SKB_RXCB(hdr_skb);1114		memset(rxs, 0, sizeof(struct ieee80211_rx_status));1115 1116		retval = ath9k_rx_skb_preprocess(sc, hdr_skb, &rs, rxs,1117						 &decrypt_error, tsf);1118		if (retval)1119			goto requeue_drop_frag;1120 1121		/* Ensure we always have an skb to requeue once we are done1122		 * processing the current buffer's skb */1123		requeue_skb = ath_rxbuf_alloc(common, common->rx_bufsize, GFP_ATOMIC);1124 1125		/* If there is no memory we ignore the current RX'd frame,1126		 * tell hardware it can give us a new frame using the old1127		 * skb and put it at the tail of the sc->rx.rxbuf list for1128		 * processing. */1129		if (!requeue_skb) {1130			RX_STAT_INC(sc, rx_oom_err);1131			goto requeue_drop_frag;1132		}1133 1134		/* We will now give hardware our shiny new allocated skb */1135		new_buf_addr = dma_map_single(sc->dev, requeue_skb->data,1136					      common->rx_bufsize, dma_type);1137		if (unlikely(dma_mapping_error(sc->dev, new_buf_addr))) {1138			dev_kfree_skb_any(requeue_skb);1139			goto requeue_drop_frag;1140		}1141 1142		/* Unmap the frame */1143		dma_unmap_single(sc->dev, bf->bf_buf_addr,1144				 common->rx_bufsize, dma_type);1145 1146		bf->bf_mpdu = requeue_skb;1147		bf->bf_buf_addr = new_buf_addr;1148 1149		skb_put(skb, rs.rs_datalen + ah->caps.rx_status_len);1150		if (ah->caps.rx_status_len)1151			skb_pull(skb, ah->caps.rx_status_len);1152 1153		if (!rs.rs_more)1154			ath9k_cmn_rx_skb_postprocess(common, hdr_skb, &rs,1155						     rxs, decrypt_error);1156 1157		if (rs.rs_more) {1158			RX_STAT_INC(sc, rx_frags);1159			/*1160			 * rs_more indicates chained descriptors which can be1161			 * used to link buffers together for a sort of1162			 * scatter-gather operation.1163			 */1164			if (sc->rx.frag) {1165				/* too many fragments - cannot handle frame */1166				dev_kfree_skb_any(sc->rx.frag);1167				dev_kfree_skb_any(skb);1168				RX_STAT_INC(sc, rx_too_many_frags_err);1169				skb = NULL;1170			}1171			sc->rx.frag = skb;1172			goto requeue;1173		}1174 1175		if (sc->rx.frag) {1176			int space = skb->len - skb_tailroom(hdr_skb);1177 1178			if (pskb_expand_head(hdr_skb, 0, space, GFP_ATOMIC) < 0) {1179				dev_kfree_skb(skb);1180				RX_STAT_INC(sc, rx_oom_err);1181				goto requeue_drop_frag;1182			}1183 1184			sc->rx.frag = NULL;1185 1186			skb_copy_from_linear_data(skb, skb_put(hdr_skb, skb->len),1187						  skb->len);1188			dev_kfree_skb_any(skb);1189			skb = hdr_skb;1190		}1191 1192		if (rxs->flag & RX_FLAG_MMIC_STRIPPED)1193			skb_trim(skb, skb->len - 8);1194 1195		spin_lock_irqsave(&sc->sc_pm_lock, flags);1196		if ((sc->ps_flags & (PS_WAIT_FOR_BEACON |1197				     PS_WAIT_FOR_CAB |1198				     PS_WAIT_FOR_PSPOLL_DATA)) ||1199		    ath9k_check_auto_sleep(sc))1200			ath_rx_ps(sc, skb, rs.is_mybeacon);1201		spin_unlock_irqrestore(&sc->sc_pm_lock, flags);1202 1203		ath9k_antenna_check(sc, &rs);1204		ath9k_apply_ampdu_details(sc, &rs, rxs);1205		ath_debug_rate_stats(sc, &rs, skb);1206		ath_rx_count_airtime(sc, &rs, skb);1207 1208		hdr = (struct ieee80211_hdr *)skb->data;1209		if (ieee80211_is_ack(hdr->frame_control))1210			ath_dynack_sample_ack_ts(sc->sc_ah, skb, rs.rs_tstamp);1211 1212		ieee80211_rx(hw, skb);1213 1214requeue_drop_frag:1215		if (sc->rx.frag) {1216			dev_kfree_skb_any(sc->rx.frag);1217			sc->rx.frag = NULL;1218		}1219requeue:1220		list_add_tail(&bf->list, &sc->rx.rxbuf);1221 1222		if (!edma) {1223			ath_rx_buf_relink(sc, bf, flush);1224			if (!flush)1225				ath9k_hw_rxena(ah);1226		} else if (!flush) {1227			ath_rx_edma_buf_link(sc, qtype);1228		}1229 1230		if (!budget--)1231			break;1232	} while (1);1233 1234	if (!(ah->imask & ATH9K_INT_RXEOL)) {1235		ah->imask |= (ATH9K_INT_RXEOL | ATH9K_INT_RXORN);1236		ath9k_hw_set_interrupts(ah);1237	}1238 1239	return 0;1240}1241