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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 any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <linux/dma-mapping.h>
18 #include "ath9k.h"
19 #include "ar9003_mac.h"
20 
21 #define SKB_CB_ATHBUF(__skb)	(*((struct ath_buf **)__skb->cb))
22 
ath_is_alt_ant_ratio_better(int alt_ratio,int maxdelta,int mindelta,int main_rssi_avg,int alt_rssi_avg,int pkt_count)23 static inline bool ath_is_alt_ant_ratio_better(int alt_ratio, int maxdelta,
24 					       int mindelta, int main_rssi_avg,
25 					       int alt_rssi_avg, int pkt_count)
26 {
27 	return (((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
28 		(alt_rssi_avg > main_rssi_avg + maxdelta)) ||
29 		(alt_rssi_avg > main_rssi_avg + mindelta)) && (pkt_count > 50);
30 }
31 
ath_ant_div_comb_alt_check(u8 div_group,int alt_ratio,int curr_main_set,int curr_alt_set,int alt_rssi_avg,int main_rssi_avg)32 static inline bool ath_ant_div_comb_alt_check(u8 div_group, int alt_ratio,
33 					int curr_main_set, int curr_alt_set,
34 					int alt_rssi_avg, int main_rssi_avg)
35 {
36 	bool result = false;
37 	switch (div_group) {
38 	case 0:
39 		if (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO)
40 			result = true;
41 		break;
42 	case 1:
43 	case 2:
44 		if ((((curr_main_set == ATH_ANT_DIV_COMB_LNA2) &&
45 			(curr_alt_set == ATH_ANT_DIV_COMB_LNA1) &&
46 				(alt_rssi_avg >= (main_rssi_avg - 5))) ||
47 			((curr_main_set == ATH_ANT_DIV_COMB_LNA1) &&
48 			(curr_alt_set == ATH_ANT_DIV_COMB_LNA2) &&
49 				(alt_rssi_avg >= (main_rssi_avg - 2)))) &&
50 							(alt_rssi_avg >= 4))
51 			result = true;
52 		else
53 			result = false;
54 		break;
55 	}
56 
57 	return result;
58 }
59 
ath9k_check_auto_sleep(struct ath_softc * sc)60 static inline bool ath9k_check_auto_sleep(struct ath_softc *sc)
61 {
62 	return sc->ps_enabled &&
63 	       (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_AUTOSLEEP);
64 }
65 
66 /*
67  * Setup and link descriptors.
68  *
69  * 11N: we can no longer afford to self link the last descriptor.
70  * MAC acknowledges BA status as long as it copies frames to host
71  * buffer (or rx fifo). This can incorrectly acknowledge packets
72  * to a sender if last desc is self-linked.
73  */
ath_rx_buf_link(struct ath_softc * sc,struct ath_buf * bf)74 static void ath_rx_buf_link(struct ath_softc *sc, struct ath_buf *bf)
75 {
76 	struct ath_hw *ah = sc->sc_ah;
77 	struct ath_common *common = ath9k_hw_common(ah);
78 	struct ath_desc *ds;
79 	struct sk_buff *skb;
80 
81 	ds = bf->bf_desc;
82 	ds->ds_link = 0; /* link to null */
83 	ds->ds_data = bf->bf_buf_addr;
84 
85 	/* virtual addr of the beginning of the buffer. */
86 	skb = bf->bf_mpdu;
87 	BUG_ON(skb == NULL);
88 	ds->ds_vdata = skb->data;
89 
90 	/*
91 	 * setup rx descriptors. The rx_bufsize here tells the hardware
92 	 * how much data it can DMA to us and that we are prepared
93 	 * to process
94 	 */
95 	ath9k_hw_setuprxdesc(ah, ds,
96 			     common->rx_bufsize,
97 			     0);
98 
99 	if (sc->rx.rxlink == NULL)
100 		ath9k_hw_putrxbuf(ah, bf->bf_daddr);
101 	else
102 		*sc->rx.rxlink = bf->bf_daddr;
103 
104 	sc->rx.rxlink = &ds->ds_link;
105 }
106 
ath_rx_buf_relink(struct ath_softc * sc,struct ath_buf * bf)107 static void ath_rx_buf_relink(struct ath_softc *sc, struct ath_buf *bf)
108 {
109 	if (sc->rx.buf_hold)
110 		ath_rx_buf_link(sc, sc->rx.buf_hold);
111 
112 	sc->rx.buf_hold = bf;
113 }
114 
ath_setdefantenna(struct ath_softc * sc,u32 antenna)115 static void ath_setdefantenna(struct ath_softc *sc, u32 antenna)
116 {
117 	/* XXX block beacon interrupts */
118 	ath9k_hw_setantenna(sc->sc_ah, antenna);
119 	sc->rx.defant = antenna;
120 	sc->rx.rxotherant = 0;
121 }
122 
ath_opmode_init(struct ath_softc * sc)123 static void ath_opmode_init(struct ath_softc *sc)
124 {
125 	struct ath_hw *ah = sc->sc_ah;
126 	struct ath_common *common = ath9k_hw_common(ah);
127 
128 	u32 rfilt, mfilt[2];
129 
130 	/* configure rx filter */
131 	rfilt = ath_calcrxfilter(sc);
132 	ath9k_hw_setrxfilter(ah, rfilt);
133 
134 	/* configure bssid mask */
135 	ath_hw_setbssidmask(common);
136 
137 	/* configure operational mode */
138 	ath9k_hw_setopmode(ah);
139 
140 	/* calculate and install multicast filter */
141 	mfilt[0] = mfilt[1] = ~0;
142 	ath9k_hw_setmcastfilter(ah, mfilt[0], mfilt[1]);
143 }
144 
ath_rx_edma_buf_link(struct ath_softc * sc,enum ath9k_rx_qtype qtype)145 static bool ath_rx_edma_buf_link(struct ath_softc *sc,
146 				 enum ath9k_rx_qtype qtype)
147 {
148 	struct ath_hw *ah = sc->sc_ah;
149 	struct ath_rx_edma *rx_edma;
150 	struct sk_buff *skb;
151 	struct ath_buf *bf;
152 
153 	rx_edma = &sc->rx.rx_edma[qtype];
154 	if (skb_queue_len(&rx_edma->rx_fifo) >= rx_edma->rx_fifo_hwsize)
155 		return false;
156 
157 	bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
158 	list_del_init(&bf->list);
159 
160 	skb = bf->bf_mpdu;
161 
162 	memset(skb->data, 0, ah->caps.rx_status_len);
163 	dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
164 				ah->caps.rx_status_len, DMA_TO_DEVICE);
165 
166 	SKB_CB_ATHBUF(skb) = bf;
167 	ath9k_hw_addrxbuf_edma(ah, bf->bf_buf_addr, qtype);
168 	skb_queue_tail(&rx_edma->rx_fifo, skb);
169 
170 	return true;
171 }
172 
ath_rx_addbuffer_edma(struct ath_softc * sc,enum ath9k_rx_qtype qtype,int size)173 static void ath_rx_addbuffer_edma(struct ath_softc *sc,
174 				  enum ath9k_rx_qtype qtype, int size)
175 {
176 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
177 	struct ath_buf *bf, *tbf;
178 
179 	if (list_empty(&sc->rx.rxbuf)) {
180 		ath_dbg(common, QUEUE, "No free rx buf available\n");
181 		return;
182 	}
183 
184 	list_for_each_entry_safe(bf, tbf, &sc->rx.rxbuf, list)
185 		if (!ath_rx_edma_buf_link(sc, qtype))
186 			break;
187 
188 }
189 
ath_rx_remove_buffer(struct ath_softc * sc,enum ath9k_rx_qtype qtype)190 static void ath_rx_remove_buffer(struct ath_softc *sc,
191 				 enum ath9k_rx_qtype qtype)
192 {
193 	struct ath_buf *bf;
194 	struct ath_rx_edma *rx_edma;
195 	struct sk_buff *skb;
196 
197 	rx_edma = &sc->rx.rx_edma[qtype];
198 
199 	while ((skb = skb_dequeue(&rx_edma->rx_fifo)) != NULL) {
200 		bf = SKB_CB_ATHBUF(skb);
201 		BUG_ON(!bf);
202 		list_add_tail(&bf->list, &sc->rx.rxbuf);
203 	}
204 }
205 
ath_rx_edma_cleanup(struct ath_softc * sc)206 static void ath_rx_edma_cleanup(struct ath_softc *sc)
207 {
208 	struct ath_hw *ah = sc->sc_ah;
209 	struct ath_common *common = ath9k_hw_common(ah);
210 	struct ath_buf *bf;
211 
212 	ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_LP);
213 	ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_HP);
214 
215 	list_for_each_entry(bf, &sc->rx.rxbuf, list) {
216 		if (bf->bf_mpdu) {
217 			dma_unmap_single(sc->dev, bf->bf_buf_addr,
218 					common->rx_bufsize,
219 					DMA_BIDIRECTIONAL);
220 			dev_kfree_skb_any(bf->bf_mpdu);
221 			bf->bf_buf_addr = 0;
222 			bf->bf_mpdu = NULL;
223 		}
224 	}
225 
226 	INIT_LIST_HEAD(&sc->rx.rxbuf);
227 
228 	kfree(sc->rx.rx_bufptr);
229 	sc->rx.rx_bufptr = NULL;
230 }
231 
ath_rx_edma_init_queue(struct ath_rx_edma * rx_edma,int size)232 static void ath_rx_edma_init_queue(struct ath_rx_edma *rx_edma, int size)
233 {
234 	skb_queue_head_init(&rx_edma->rx_fifo);
235 	rx_edma->rx_fifo_hwsize = size;
236 }
237 
ath_rx_edma_init(struct ath_softc * sc,int nbufs)238 static int ath_rx_edma_init(struct ath_softc *sc, int nbufs)
239 {
240 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
241 	struct ath_hw *ah = sc->sc_ah;
242 	struct sk_buff *skb;
243 	struct ath_buf *bf;
244 	int error = 0, i;
245 	u32 size;
246 
247 	ath9k_hw_set_rx_bufsize(ah, common->rx_bufsize -
248 				    ah->caps.rx_status_len);
249 
250 	ath_rx_edma_init_queue(&sc->rx.rx_edma[ATH9K_RX_QUEUE_LP],
251 			       ah->caps.rx_lp_qdepth);
252 	ath_rx_edma_init_queue(&sc->rx.rx_edma[ATH9K_RX_QUEUE_HP],
253 			       ah->caps.rx_hp_qdepth);
254 
255 	size = sizeof(struct ath_buf) * nbufs;
256 	bf = kzalloc(size, GFP_KERNEL);
257 	if (!bf)
258 		return -ENOMEM;
259 
260 	INIT_LIST_HEAD(&sc->rx.rxbuf);
261 	sc->rx.rx_bufptr = bf;
262 
263 	for (i = 0; i < nbufs; i++, bf++) {
264 		skb = ath_rxbuf_alloc(common, common->rx_bufsize, GFP_KERNEL);
265 		if (!skb) {
266 			error = -ENOMEM;
267 			goto rx_init_fail;
268 		}
269 
270 		memset(skb->data, 0, common->rx_bufsize);
271 		bf->bf_mpdu = skb;
272 
273 		bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
274 						 common->rx_bufsize,
275 						 DMA_BIDIRECTIONAL);
276 		if (unlikely(dma_mapping_error(sc->dev,
277 						bf->bf_buf_addr))) {
278 				dev_kfree_skb_any(skb);
279 				bf->bf_mpdu = NULL;
280 				bf->bf_buf_addr = 0;
281 				ath_err(common,
282 					"dma_mapping_error() on RX init\n");
283 				error = -ENOMEM;
284 				goto rx_init_fail;
285 		}
286 
287 		list_add_tail(&bf->list, &sc->rx.rxbuf);
288 	}
289 
290 	return 0;
291 
292 rx_init_fail:
293 	ath_rx_edma_cleanup(sc);
294 	return error;
295 }
296 
ath_edma_start_recv(struct ath_softc * sc)297 static void ath_edma_start_recv(struct ath_softc *sc)
298 {
299 	spin_lock_bh(&sc->rx.rxbuflock);
300 
301 	ath9k_hw_rxena(sc->sc_ah);
302 
303 	ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_HP,
304 			      sc->rx.rx_edma[ATH9K_RX_QUEUE_HP].rx_fifo_hwsize);
305 
306 	ath_rx_addbuffer_edma(sc, ATH9K_RX_QUEUE_LP,
307 			      sc->rx.rx_edma[ATH9K_RX_QUEUE_LP].rx_fifo_hwsize);
308 
309 	ath_opmode_init(sc);
310 
311 	ath9k_hw_startpcureceive(sc->sc_ah, (sc->sc_flags & SC_OP_OFFCHANNEL));
312 
313 	spin_unlock_bh(&sc->rx.rxbuflock);
314 }
315 
ath_edma_stop_recv(struct ath_softc * sc)316 static void ath_edma_stop_recv(struct ath_softc *sc)
317 {
318 	ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_HP);
319 	ath_rx_remove_buffer(sc, ATH9K_RX_QUEUE_LP);
320 }
321 
ath_rx_init(struct ath_softc * sc,int nbufs)322 int ath_rx_init(struct ath_softc *sc, int nbufs)
323 {
324 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
325 	struct sk_buff *skb;
326 	struct ath_buf *bf;
327 	int error = 0;
328 
329 	spin_lock_init(&sc->sc_pcu_lock);
330 	sc->sc_flags &= ~SC_OP_RXFLUSH;
331 	spin_lock_init(&sc->rx.rxbuflock);
332 
333 	common->rx_bufsize = IEEE80211_MAX_MPDU_LEN / 2 +
334 			     sc->sc_ah->caps.rx_status_len;
335 
336 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
337 		return ath_rx_edma_init(sc, nbufs);
338 	} else {
339 		ath_dbg(common, CONFIG, "cachelsz %u rxbufsize %u\n",
340 			common->cachelsz, common->rx_bufsize);
341 
342 		/* Initialize rx descriptors */
343 
344 		error = ath_descdma_setup(sc, &sc->rx.rxdma, &sc->rx.rxbuf,
345 				"rx", nbufs, 1, 0);
346 		if (error != 0) {
347 			ath_err(common,
348 				"failed to allocate rx descriptors: %d\n",
349 				error);
350 			goto err;
351 		}
352 
353 		list_for_each_entry(bf, &sc->rx.rxbuf, list) {
354 			skb = ath_rxbuf_alloc(common, common->rx_bufsize,
355 					      GFP_KERNEL);
356 			if (skb == NULL) {
357 				error = -ENOMEM;
358 				goto err;
359 			}
360 
361 			bf->bf_mpdu = skb;
362 			bf->bf_buf_addr = dma_map_single(sc->dev, skb->data,
363 					common->rx_bufsize,
364 					DMA_FROM_DEVICE);
365 			if (unlikely(dma_mapping_error(sc->dev,
366 							bf->bf_buf_addr))) {
367 				dev_kfree_skb_any(skb);
368 				bf->bf_mpdu = NULL;
369 				bf->bf_buf_addr = 0;
370 				ath_err(common,
371 					"dma_mapping_error() on RX init\n");
372 				error = -ENOMEM;
373 				goto err;
374 			}
375 		}
376 		sc->rx.rxlink = NULL;
377 	}
378 
379 err:
380 	if (error)
381 		ath_rx_cleanup(sc);
382 
383 	return error;
384 }
385 
ath_rx_cleanup(struct ath_softc * sc)386 void ath_rx_cleanup(struct ath_softc *sc)
387 {
388 	struct ath_hw *ah = sc->sc_ah;
389 	struct ath_common *common = ath9k_hw_common(ah);
390 	struct sk_buff *skb;
391 	struct ath_buf *bf;
392 
393 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
394 		ath_rx_edma_cleanup(sc);
395 		return;
396 	} else {
397 		list_for_each_entry(bf, &sc->rx.rxbuf, list) {
398 			skb = bf->bf_mpdu;
399 			if (skb) {
400 				dma_unmap_single(sc->dev, bf->bf_buf_addr,
401 						common->rx_bufsize,
402 						DMA_FROM_DEVICE);
403 				dev_kfree_skb(skb);
404 				bf->bf_buf_addr = 0;
405 				bf->bf_mpdu = NULL;
406 			}
407 		}
408 
409 		if (sc->rx.rxdma.dd_desc_len != 0)
410 			ath_descdma_cleanup(sc, &sc->rx.rxdma, &sc->rx.rxbuf);
411 	}
412 }
413 
414 /*
415  * Calculate the receive filter according to the
416  * operating mode and state:
417  *
418  * o always accept unicast, broadcast, and multicast traffic
419  * o maintain current state of phy error reception (the hal
420  *   may enable phy error frames for noise immunity work)
421  * o probe request frames are accepted only when operating in
422  *   hostap, adhoc, or monitor modes
423  * o enable promiscuous mode according to the interface state
424  * o accept beacons:
425  *   - when operating in adhoc mode so the 802.11 layer creates
426  *     node table entries for peers,
427  *   - when operating in station mode for collecting rssi data when
428  *     the station is otherwise quiet, or
429  *   - when operating as a repeater so we see repeater-sta beacons
430  *   - when scanning
431  */
432 
ath_calcrxfilter(struct ath_softc * sc)433 u32 ath_calcrxfilter(struct ath_softc *sc)
434 {
435 	u32 rfilt;
436 
437 	rfilt = ATH9K_RX_FILTER_UCAST | ATH9K_RX_FILTER_BCAST
438 		| ATH9K_RX_FILTER_MCAST;
439 
440 	if (sc->rx.rxfilter & FIF_PROBE_REQ)
441 		rfilt |= ATH9K_RX_FILTER_PROBEREQ;
442 
443 	/*
444 	 * Set promiscuous mode when FIF_PROMISC_IN_BSS is enabled for station
445 	 * mode interface or when in monitor mode. AP mode does not need this
446 	 * since it receives all in-BSS frames anyway.
447 	 */
448 	if (sc->sc_ah->is_monitoring)
449 		rfilt |= ATH9K_RX_FILTER_PROM;
450 
451 	if (sc->rx.rxfilter & FIF_CONTROL)
452 		rfilt |= ATH9K_RX_FILTER_CONTROL;
453 
454 	if ((sc->sc_ah->opmode == NL80211_IFTYPE_STATION) &&
455 	    (sc->nvifs <= 1) &&
456 	    !(sc->rx.rxfilter & FIF_BCN_PRBRESP_PROMISC))
457 		rfilt |= ATH9K_RX_FILTER_MYBEACON;
458 	else
459 		rfilt |= ATH9K_RX_FILTER_BEACON;
460 
461 	if ((sc->sc_ah->opmode == NL80211_IFTYPE_AP) ||
462 	    (sc->rx.rxfilter & FIF_PSPOLL))
463 		rfilt |= ATH9K_RX_FILTER_PSPOLL;
464 
465 	if (conf_is_ht(&sc->hw->conf))
466 		rfilt |= ATH9K_RX_FILTER_COMP_BAR;
467 
468 	if (sc->nvifs > 1 || (sc->rx.rxfilter & FIF_OTHER_BSS)) {
469 		/* The following may also be needed for other older chips */
470 		if (sc->sc_ah->hw_version.macVersion == AR_SREV_VERSION_9160)
471 			rfilt |= ATH9K_RX_FILTER_PROM;
472 		rfilt |= ATH9K_RX_FILTER_MCAST_BCAST_ALL;
473 	}
474 
475 	return rfilt;
476 
477 }
478 
ath_startrecv(struct ath_softc * sc)479 int ath_startrecv(struct ath_softc *sc)
480 {
481 	struct ath_hw *ah = sc->sc_ah;
482 	struct ath_buf *bf, *tbf;
483 
484 	if (ah->caps.hw_caps & ATH9K_HW_CAP_EDMA) {
485 		ath_edma_start_recv(sc);
486 		return 0;
487 	}
488 
489 	spin_lock_bh(&sc->rx.rxbuflock);
490 	if (list_empty(&sc->rx.rxbuf))
491 		goto start_recv;
492 
493 	sc->rx.buf_hold = NULL;
494 	sc->rx.rxlink = NULL;
495 	list_for_each_entry_safe(bf, tbf, &sc->rx.rxbuf, list) {
496 		ath_rx_buf_link(sc, bf);
497 	}
498 
499 	/* We could have deleted elements so the list may be empty now */
500 	if (list_empty(&sc->rx.rxbuf))
501 		goto start_recv;
502 
503 	bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
504 	ath9k_hw_putrxbuf(ah, bf->bf_daddr);
505 	ath9k_hw_rxena(ah);
506 
507 start_recv:
508 	ath_opmode_init(sc);
509 	ath9k_hw_startpcureceive(ah, (sc->sc_flags & SC_OP_OFFCHANNEL));
510 
511 	spin_unlock_bh(&sc->rx.rxbuflock);
512 
513 	return 0;
514 }
515 
ath_stoprecv(struct ath_softc * sc)516 bool ath_stoprecv(struct ath_softc *sc)
517 {
518 	struct ath_hw *ah = sc->sc_ah;
519 	bool stopped, reset = false;
520 
521 	spin_lock_bh(&sc->rx.rxbuflock);
522 	ath9k_hw_abortpcurecv(ah);
523 	ath9k_hw_setrxfilter(ah, 0);
524 	stopped = ath9k_hw_stopdmarecv(ah, &reset);
525 
526 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
527 		ath_edma_stop_recv(sc);
528 	else
529 		sc->rx.rxlink = NULL;
530 	spin_unlock_bh(&sc->rx.rxbuflock);
531 
532 	if (!(ah->ah_flags & AH_UNPLUGGED) &&
533 	    unlikely(!stopped)) {
534 		ath_err(ath9k_hw_common(sc->sc_ah),
535 			"Could not stop RX, we could be "
536 			"confusing the DMA engine when we start RX up\n");
537 		ATH_DBG_WARN_ON_ONCE(!stopped);
538 	}
539 	return stopped && !reset;
540 }
541 
ath_flushrecv(struct ath_softc * sc)542 void ath_flushrecv(struct ath_softc *sc)
543 {
544 	sc->sc_flags |= SC_OP_RXFLUSH;
545 	if (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_EDMA)
546 		ath_rx_tasklet(sc, 1, true);
547 	ath_rx_tasklet(sc, 1, false);
548 	sc->sc_flags &= ~SC_OP_RXFLUSH;
549 }
550 
ath_beacon_dtim_pending_cab(struct sk_buff * skb)551 static bool ath_beacon_dtim_pending_cab(struct sk_buff *skb)
552 {
553 	/* Check whether the Beacon frame has DTIM indicating buffered bc/mc */
554 	struct ieee80211_mgmt *mgmt;
555 	u8 *pos, *end, id, elen;
556 	struct ieee80211_tim_ie *tim;
557 
558 	mgmt = (struct ieee80211_mgmt *)skb->data;
559 	pos = mgmt->u.beacon.variable;
560 	end = skb->data + skb->len;
561 
562 	while (pos + 2 < end) {
563 		id = *pos++;
564 		elen = *pos++;
565 		if (pos + elen > end)
566 			break;
567 
568 		if (id == WLAN_EID_TIM) {
569 			if (elen < sizeof(*tim))
570 				break;
571 			tim = (struct ieee80211_tim_ie *) pos;
572 			if (tim->dtim_count != 0)
573 				break;
574 			return tim->bitmap_ctrl & 0x01;
575 		}
576 
577 		pos += elen;
578 	}
579 
580 	return false;
581 }
582 
ath_rx_ps_beacon(struct ath_softc * sc,struct sk_buff * skb)583 static void ath_rx_ps_beacon(struct ath_softc *sc, struct sk_buff *skb)
584 {
585 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
586 
587 	if (skb->len < 24 + 8 + 2 + 2)
588 		return;
589 
590 	sc->ps_flags &= ~PS_WAIT_FOR_BEACON;
591 
592 	if (sc->ps_flags & PS_BEACON_SYNC) {
593 		sc->ps_flags &= ~PS_BEACON_SYNC;
594 		ath_dbg(common, PS,
595 			"Reconfigure Beacon timers based on timestamp from the AP\n");
596 		ath_set_beacon(sc);
597 	}
598 
599 	if (ath_beacon_dtim_pending_cab(skb)) {
600 		/*
601 		 * Remain awake waiting for buffered broadcast/multicast
602 		 * frames. If the last broadcast/multicast frame is not
603 		 * received properly, the next beacon frame will work as
604 		 * a backup trigger for returning into NETWORK SLEEP state,
605 		 * so we are waiting for it as well.
606 		 */
607 		ath_dbg(common, PS,
608 			"Received DTIM beacon indicating buffered broadcast/multicast frame(s)\n");
609 		sc->ps_flags |= PS_WAIT_FOR_CAB | PS_WAIT_FOR_BEACON;
610 		return;
611 	}
612 
613 	if (sc->ps_flags & PS_WAIT_FOR_CAB) {
614 		/*
615 		 * This can happen if a broadcast frame is dropped or the AP
616 		 * fails to send a frame indicating that all CAB frames have
617 		 * been delivered.
618 		 */
619 		sc->ps_flags &= ~PS_WAIT_FOR_CAB;
620 		ath_dbg(common, PS, "PS wait for CAB frames timed out\n");
621 	}
622 }
623 
ath_rx_ps(struct ath_softc * sc,struct sk_buff * skb,bool mybeacon)624 static void ath_rx_ps(struct ath_softc *sc, struct sk_buff *skb, bool mybeacon)
625 {
626 	struct ieee80211_hdr *hdr;
627 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
628 
629 	hdr = (struct ieee80211_hdr *)skb->data;
630 
631 	/* Process Beacon and CAB receive in PS state */
632 	if (((sc->ps_flags & PS_WAIT_FOR_BEACON) || ath9k_check_auto_sleep(sc))
633 	    && mybeacon)
634 		ath_rx_ps_beacon(sc, skb);
635 	else if ((sc->ps_flags & PS_WAIT_FOR_CAB) &&
636 		 (ieee80211_is_data(hdr->frame_control) ||
637 		  ieee80211_is_action(hdr->frame_control)) &&
638 		 is_multicast_ether_addr(hdr->addr1) &&
639 		 !ieee80211_has_moredata(hdr->frame_control)) {
640 		/*
641 		 * No more broadcast/multicast frames to be received at this
642 		 * point.
643 		 */
644 		sc->ps_flags &= ~(PS_WAIT_FOR_CAB | PS_WAIT_FOR_BEACON);
645 		ath_dbg(common, PS,
646 			"All PS CAB frames received, back to sleep\n");
647 	} else if ((sc->ps_flags & PS_WAIT_FOR_PSPOLL_DATA) &&
648 		   !is_multicast_ether_addr(hdr->addr1) &&
649 		   !ieee80211_has_morefrags(hdr->frame_control)) {
650 		sc->ps_flags &= ~PS_WAIT_FOR_PSPOLL_DATA;
651 		ath_dbg(common, PS,
652 			"Going back to sleep after having received PS-Poll data (0x%lx)\n",
653 			sc->ps_flags & (PS_WAIT_FOR_BEACON |
654 					PS_WAIT_FOR_CAB |
655 					PS_WAIT_FOR_PSPOLL_DATA |
656 					PS_WAIT_FOR_TX_ACK));
657 	}
658 }
659 
ath_edma_get_buffers(struct ath_softc * sc,enum ath9k_rx_qtype qtype,struct ath_rx_status * rs,struct ath_buf ** dest)660 static bool ath_edma_get_buffers(struct ath_softc *sc,
661 				 enum ath9k_rx_qtype qtype,
662 				 struct ath_rx_status *rs,
663 				 struct ath_buf **dest)
664 {
665 	struct ath_rx_edma *rx_edma = &sc->rx.rx_edma[qtype];
666 	struct ath_hw *ah = sc->sc_ah;
667 	struct ath_common *common = ath9k_hw_common(ah);
668 	struct sk_buff *skb;
669 	struct ath_buf *bf;
670 	int ret;
671 
672 	skb = skb_peek(&rx_edma->rx_fifo);
673 	if (!skb)
674 		return false;
675 
676 	bf = SKB_CB_ATHBUF(skb);
677 	BUG_ON(!bf);
678 
679 	dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
680 				common->rx_bufsize, DMA_FROM_DEVICE);
681 
682 	ret = ath9k_hw_process_rxdesc_edma(ah, rs, skb->data);
683 	if (ret == -EINPROGRESS) {
684 		/*let device gain the buffer again*/
685 		dma_sync_single_for_device(sc->dev, bf->bf_buf_addr,
686 				common->rx_bufsize, DMA_FROM_DEVICE);
687 		return false;
688 	}
689 
690 	__skb_unlink(skb, &rx_edma->rx_fifo);
691 	if (ret == -EINVAL) {
692 		/* corrupt descriptor, skip this one and the following one */
693 		list_add_tail(&bf->list, &sc->rx.rxbuf);
694 		ath_rx_edma_buf_link(sc, qtype);
695 
696 		skb = skb_peek(&rx_edma->rx_fifo);
697 		if (skb) {
698 			bf = SKB_CB_ATHBUF(skb);
699 			BUG_ON(!bf);
700 
701 			__skb_unlink(skb, &rx_edma->rx_fifo);
702 			list_add_tail(&bf->list, &sc->rx.rxbuf);
703 			ath_rx_edma_buf_link(sc, qtype);
704 		}
705 
706 		bf = NULL;
707 	}
708 
709 	*dest = bf;
710 	return true;
711 }
712 
ath_edma_get_next_rx_buf(struct ath_softc * sc,struct ath_rx_status * rs,enum ath9k_rx_qtype qtype)713 static struct ath_buf *ath_edma_get_next_rx_buf(struct ath_softc *sc,
714 						struct ath_rx_status *rs,
715 						enum ath9k_rx_qtype qtype)
716 {
717 	struct ath_buf *bf = NULL;
718 
719 	while (ath_edma_get_buffers(sc, qtype, rs, &bf)) {
720 		if (!bf)
721 			continue;
722 
723 		return bf;
724 	}
725 	return NULL;
726 }
727 
ath_get_next_rx_buf(struct ath_softc * sc,struct ath_rx_status * rs)728 static struct ath_buf *ath_get_next_rx_buf(struct ath_softc *sc,
729 					   struct ath_rx_status *rs)
730 {
731 	struct ath_hw *ah = sc->sc_ah;
732 	struct ath_common *common = ath9k_hw_common(ah);
733 	struct ath_desc *ds;
734 	struct ath_buf *bf;
735 	int ret;
736 
737 	if (list_empty(&sc->rx.rxbuf)) {
738 		sc->rx.rxlink = NULL;
739 		return NULL;
740 	}
741 
742 	bf = list_first_entry(&sc->rx.rxbuf, struct ath_buf, list);
743 	if (bf == sc->rx.buf_hold)
744 		return NULL;
745 
746 	ds = bf->bf_desc;
747 
748 	/*
749 	 * Must provide the virtual address of the current
750 	 * descriptor, the physical address, and the virtual
751 	 * address of the next descriptor in the h/w chain.
752 	 * This allows the HAL to look ahead to see if the
753 	 * hardware is done with a descriptor by checking the
754 	 * done bit in the following descriptor and the address
755 	 * of the current descriptor the DMA engine is working
756 	 * on.  All this is necessary because of our use of
757 	 * a self-linked list to avoid rx overruns.
758 	 */
759 	ret = ath9k_hw_rxprocdesc(ah, ds, rs);
760 	if (ret == -EINPROGRESS) {
761 		struct ath_rx_status trs;
762 		struct ath_buf *tbf;
763 		struct ath_desc *tds;
764 
765 		memset(&trs, 0, sizeof(trs));
766 		if (list_is_last(&bf->list, &sc->rx.rxbuf)) {
767 			sc->rx.rxlink = NULL;
768 			return NULL;
769 		}
770 
771 		tbf = list_entry(bf->list.next, struct ath_buf, list);
772 
773 		/*
774 		 * On some hardware the descriptor status words could
775 		 * get corrupted, including the done bit. Because of
776 		 * this, check if the next descriptor's done bit is
777 		 * set or not.
778 		 *
779 		 * If the next descriptor's done bit is set, the current
780 		 * descriptor has been corrupted. Force s/w to discard
781 		 * this descriptor and continue...
782 		 */
783 
784 		tds = tbf->bf_desc;
785 		ret = ath9k_hw_rxprocdesc(ah, tds, &trs);
786 		if (ret == -EINPROGRESS)
787 			return NULL;
788 	}
789 
790 	list_del(&bf->list);
791 	if (!bf->bf_mpdu)
792 		return bf;
793 
794 	/*
795 	 * Synchronize the DMA transfer with CPU before
796 	 * 1. accessing the frame
797 	 * 2. requeueing the same buffer to h/w
798 	 */
799 	dma_sync_single_for_cpu(sc->dev, bf->bf_buf_addr,
800 			common->rx_bufsize,
801 			DMA_FROM_DEVICE);
802 
803 	return bf;
804 }
805 
806 /* Assumes you've already done the endian to CPU conversion */
ath9k_rx_accept(struct ath_common * common,struct ieee80211_hdr * hdr,struct ieee80211_rx_status * rxs,struct ath_rx_status * rx_stats,bool * decrypt_error)807 static bool ath9k_rx_accept(struct ath_common *common,
808 			    struct ieee80211_hdr *hdr,
809 			    struct ieee80211_rx_status *rxs,
810 			    struct ath_rx_status *rx_stats,
811 			    bool *decrypt_error)
812 {
813 	struct ath_softc *sc = (struct ath_softc *) common->priv;
814 	bool is_mc, is_valid_tkip, strip_mic, mic_error;
815 	struct ath_hw *ah = common->ah;
816 	__le16 fc;
817 	u8 rx_status_len = ah->caps.rx_status_len;
818 
819 	fc = hdr->frame_control;
820 
821 	is_mc = !!is_multicast_ether_addr(hdr->addr1);
822 	is_valid_tkip = rx_stats->rs_keyix != ATH9K_RXKEYIX_INVALID &&
823 		test_bit(rx_stats->rs_keyix, common->tkip_keymap);
824 	strip_mic = is_valid_tkip && ieee80211_is_data(fc) &&
825 		!(rx_stats->rs_status &
826 		(ATH9K_RXERR_DECRYPT | ATH9K_RXERR_CRC | ATH9K_RXERR_MIC |
827 		 ATH9K_RXERR_KEYMISS));
828 
829 	/*
830 	 * Key miss events are only relevant for pairwise keys where the
831 	 * descriptor does contain a valid key index. This has been observed
832 	 * mostly with CCMP encryption.
833 	 */
834 	if (rx_stats->rs_keyix == ATH9K_RXKEYIX_INVALID ||
835 	    !test_bit(rx_stats->rs_keyix, common->ccmp_keymap))
836 		rx_stats->rs_status &= ~ATH9K_RXERR_KEYMISS;
837 
838 	if (!rx_stats->rs_datalen)
839 		return false;
840         /*
841          * rs_status follows rs_datalen so if rs_datalen is too large
842          * we can take a hint that hardware corrupted it, so ignore
843          * those frames.
844          */
845 	if (rx_stats->rs_datalen > (common->rx_bufsize - rx_status_len))
846 		return false;
847 
848 	/* Only use error bits from the last fragment */
849 	if (rx_stats->rs_more)
850 		return true;
851 
852 	mic_error = is_valid_tkip && !ieee80211_is_ctl(fc) &&
853 		!ieee80211_has_morefrags(fc) &&
854 		!(le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG) &&
855 		(rx_stats->rs_status & ATH9K_RXERR_MIC);
856 
857 	/*
858 	 * The rx_stats->rs_status will not be set until the end of the
859 	 * chained descriptors so it can be ignored if rs_more is set. The
860 	 * rs_more will be false at the last element of the chained
861 	 * descriptors.
862 	 */
863 	if (rx_stats->rs_status != 0) {
864 		u8 status_mask;
865 
866 		if (rx_stats->rs_status & ATH9K_RXERR_CRC) {
867 			rxs->flag |= RX_FLAG_FAILED_FCS_CRC;
868 			mic_error = false;
869 		}
870 		if (rx_stats->rs_status & ATH9K_RXERR_PHY)
871 			return false;
872 
873 		if ((rx_stats->rs_status & ATH9K_RXERR_DECRYPT) ||
874 		    (!is_mc && (rx_stats->rs_status & ATH9K_RXERR_KEYMISS))) {
875 			*decrypt_error = true;
876 			mic_error = false;
877 		}
878 
879 		/*
880 		 * Reject error frames with the exception of
881 		 * decryption and MIC failures. For monitor mode,
882 		 * we also ignore the CRC error.
883 		 */
884 		status_mask = ATH9K_RXERR_DECRYPT | ATH9K_RXERR_MIC |
885 			      ATH9K_RXERR_KEYMISS;
886 
887 		if (ah->is_monitoring && (sc->rx.rxfilter & FIF_FCSFAIL))
888 			status_mask |= ATH9K_RXERR_CRC;
889 
890 		if (rx_stats->rs_status & ~status_mask)
891 			return false;
892 	}
893 
894 	/*
895 	 * For unicast frames the MIC error bit can have false positives,
896 	 * so all MIC error reports need to be validated in software.
897 	 * False negatives are not common, so skip software verification
898 	 * if the hardware considers the MIC valid.
899 	 */
900 	if (strip_mic)
901 		rxs->flag |= RX_FLAG_MMIC_STRIPPED;
902 	else if (is_mc && mic_error)
903 		rxs->flag |= RX_FLAG_MMIC_ERROR;
904 
905 	return true;
906 }
907 
ath9k_process_rate(struct ath_common * common,struct ieee80211_hw * hw,struct ath_rx_status * rx_stats,struct ieee80211_rx_status * rxs)908 static int ath9k_process_rate(struct ath_common *common,
909 			      struct ieee80211_hw *hw,
910 			      struct ath_rx_status *rx_stats,
911 			      struct ieee80211_rx_status *rxs)
912 {
913 	struct ieee80211_supported_band *sband;
914 	enum ieee80211_band band;
915 	unsigned int i = 0;
916 
917 	band = hw->conf.channel->band;
918 	sband = hw->wiphy->bands[band];
919 
920 	if (rx_stats->rs_rate & 0x80) {
921 		/* HT rate */
922 		rxs->flag |= RX_FLAG_HT;
923 		if (rx_stats->rs_flags & ATH9K_RX_2040)
924 			rxs->flag |= RX_FLAG_40MHZ;
925 		if (rx_stats->rs_flags & ATH9K_RX_GI)
926 			rxs->flag |= RX_FLAG_SHORT_GI;
927 		rxs->rate_idx = rx_stats->rs_rate & 0x7f;
928 		return 0;
929 	}
930 
931 	for (i = 0; i < sband->n_bitrates; i++) {
932 		if (sband->bitrates[i].hw_value == rx_stats->rs_rate) {
933 			rxs->rate_idx = i;
934 			return 0;
935 		}
936 		if (sband->bitrates[i].hw_value_short == rx_stats->rs_rate) {
937 			rxs->flag |= RX_FLAG_SHORTPRE;
938 			rxs->rate_idx = i;
939 			return 0;
940 		}
941 	}
942 
943 	/*
944 	 * No valid hardware bitrate found -- we should not get here
945 	 * because hardware has already validated this frame as OK.
946 	 */
947 	ath_dbg(common, ANY,
948 		"unsupported hw bitrate detected 0x%02x using 1 Mbit\n",
949 		rx_stats->rs_rate);
950 
951 	return -EINVAL;
952 }
953 
ath9k_process_rssi(struct ath_common * common,struct ieee80211_hw * hw,struct ieee80211_hdr * hdr,struct ath_rx_status * rx_stats)954 static void ath9k_process_rssi(struct ath_common *common,
955 			       struct ieee80211_hw *hw,
956 			       struct ieee80211_hdr *hdr,
957 			       struct ath_rx_status *rx_stats)
958 {
959 	struct ath_softc *sc = hw->priv;
960 	struct ath_hw *ah = common->ah;
961 	int last_rssi;
962 	int rssi = rx_stats->rs_rssi;
963 
964 	if (!rx_stats->is_mybeacon ||
965 	    ((ah->opmode != NL80211_IFTYPE_STATION) &&
966 	     (ah->opmode != NL80211_IFTYPE_ADHOC)))
967 		return;
968 
969 	if (rx_stats->rs_rssi != ATH9K_RSSI_BAD && !rx_stats->rs_moreaggr)
970 		ATH_RSSI_LPF(sc->last_rssi, rx_stats->rs_rssi);
971 
972 	last_rssi = sc->last_rssi;
973 	if (likely(last_rssi != ATH_RSSI_DUMMY_MARKER))
974 		rssi = ATH_EP_RND(last_rssi, ATH_RSSI_EP_MULTIPLIER);
975 	if (rssi < 0)
976 		rssi = 0;
977 
978 	/* Update Beacon RSSI, this is used by ANI. */
979 	ah->stats.avgbrssi = rssi;
980 }
981 
982 /*
983  * For Decrypt or Demic errors, we only mark packet status here and always push
984  * up the frame up to let mac80211 handle the actual error case, be it no
985  * decryption key or real decryption error. This let us keep statistics there.
986  */
ath9k_rx_skb_preprocess(struct ath_common * common,struct ieee80211_hw * hw,struct ieee80211_hdr * hdr,struct ath_rx_status * rx_stats,struct ieee80211_rx_status * rx_status,bool * decrypt_error)987 static int ath9k_rx_skb_preprocess(struct ath_common *common,
988 				   struct ieee80211_hw *hw,
989 				   struct ieee80211_hdr *hdr,
990 				   struct ath_rx_status *rx_stats,
991 				   struct ieee80211_rx_status *rx_status,
992 				   bool *decrypt_error)
993 {
994 	struct ath_hw *ah = common->ah;
995 
996 	/*
997 	 * everything but the rate is checked here, the rate check is done
998 	 * separately to avoid doing two lookups for a rate for each frame.
999 	 */
1000 	if (!ath9k_rx_accept(common, hdr, rx_status, rx_stats, decrypt_error))
1001 		return -EINVAL;
1002 
1003 	/* Only use status info from the last fragment */
1004 	if (rx_stats->rs_more)
1005 		return 0;
1006 
1007 	ath9k_process_rssi(common, hw, hdr, rx_stats);
1008 
1009 	if (ath9k_process_rate(common, hw, rx_stats, rx_status))
1010 		return -EINVAL;
1011 
1012 	rx_status->band = hw->conf.channel->band;
1013 	rx_status->freq = hw->conf.channel->center_freq;
1014 	rx_status->signal = ah->noise + rx_stats->rs_rssi;
1015 	rx_status->antenna = rx_stats->rs_antenna;
1016 	rx_status->flag |= RX_FLAG_MACTIME_MPDU;
1017 	if (rx_stats->rs_moreaggr)
1018 		rx_status->flag |= RX_FLAG_NO_SIGNAL_VAL;
1019 
1020 	return 0;
1021 }
1022 
ath9k_rx_skb_postprocess(struct ath_common * common,struct sk_buff * skb,struct ath_rx_status * rx_stats,struct ieee80211_rx_status * rxs,bool decrypt_error)1023 static void ath9k_rx_skb_postprocess(struct ath_common *common,
1024 				     struct sk_buff *skb,
1025 				     struct ath_rx_status *rx_stats,
1026 				     struct ieee80211_rx_status *rxs,
1027 				     bool decrypt_error)
1028 {
1029 	struct ath_hw *ah = common->ah;
1030 	struct ieee80211_hdr *hdr;
1031 	int hdrlen, padpos, padsize;
1032 	u8 keyix;
1033 	__le16 fc;
1034 
1035 	/* see if any padding is done by the hw and remove it */
1036 	hdr = (struct ieee80211_hdr *) skb->data;
1037 	hdrlen = ieee80211_get_hdrlen_from_skb(skb);
1038 	fc = hdr->frame_control;
1039 	padpos = ath9k_cmn_padpos(hdr->frame_control);
1040 
1041 	/* The MAC header is padded to have 32-bit boundary if the
1042 	 * packet payload is non-zero. The general calculation for
1043 	 * padsize would take into account odd header lengths:
1044 	 * padsize = (4 - padpos % 4) % 4; However, since only
1045 	 * even-length headers are used, padding can only be 0 or 2
1046 	 * bytes and we can optimize this a bit. In addition, we must
1047 	 * not try to remove padding from short control frames that do
1048 	 * not have payload. */
1049 	padsize = padpos & 3;
1050 	if (padsize && skb->len>=padpos+padsize+FCS_LEN) {
1051 		memmove(skb->data + padsize, skb->data, padpos);
1052 		skb_pull(skb, padsize);
1053 	}
1054 
1055 	keyix = rx_stats->rs_keyix;
1056 
1057 	if (!(keyix == ATH9K_RXKEYIX_INVALID) && !decrypt_error &&
1058 	    ieee80211_has_protected(fc)) {
1059 		rxs->flag |= RX_FLAG_DECRYPTED;
1060 	} else if (ieee80211_has_protected(fc)
1061 		   && !decrypt_error && skb->len >= hdrlen + 4) {
1062 		keyix = skb->data[hdrlen + 3] >> 6;
1063 
1064 		if (test_bit(keyix, common->keymap))
1065 			rxs->flag |= RX_FLAG_DECRYPTED;
1066 	}
1067 	if (ah->sw_mgmt_crypto &&
1068 	    (rxs->flag & RX_FLAG_DECRYPTED) &&
1069 	    ieee80211_is_mgmt(fc))
1070 		/* Use software decrypt for management frames. */
1071 		rxs->flag &= ~RX_FLAG_DECRYPTED;
1072 }
1073 
ath_lnaconf_alt_good_scan(struct ath_ant_comb * antcomb,struct ath_hw_antcomb_conf ant_conf,int main_rssi_avg)1074 static void ath_lnaconf_alt_good_scan(struct ath_ant_comb *antcomb,
1075 				      struct ath_hw_antcomb_conf ant_conf,
1076 				      int main_rssi_avg)
1077 {
1078 	antcomb->quick_scan_cnt = 0;
1079 
1080 	if (ant_conf.main_lna_conf == ATH_ANT_DIV_COMB_LNA2)
1081 		antcomb->rssi_lna2 = main_rssi_avg;
1082 	else if (ant_conf.main_lna_conf == ATH_ANT_DIV_COMB_LNA1)
1083 		antcomb->rssi_lna1 = main_rssi_avg;
1084 
1085 	switch ((ant_conf.main_lna_conf << 4) | ant_conf.alt_lna_conf) {
1086 	case 0x10: /* LNA2 A-B */
1087 		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1088 		antcomb->first_quick_scan_conf =
1089 			ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1090 		antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA1;
1091 		break;
1092 	case 0x20: /* LNA1 A-B */
1093 		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1094 		antcomb->first_quick_scan_conf =
1095 			ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1096 		antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA2;
1097 		break;
1098 	case 0x21: /* LNA1 LNA2 */
1099 		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA2;
1100 		antcomb->first_quick_scan_conf =
1101 			ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1102 		antcomb->second_quick_scan_conf =
1103 			ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1104 		break;
1105 	case 0x12: /* LNA2 LNA1 */
1106 		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1;
1107 		antcomb->first_quick_scan_conf =
1108 			ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1109 		antcomb->second_quick_scan_conf =
1110 			ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1111 		break;
1112 	case 0x13: /* LNA2 A+B */
1113 		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1114 		antcomb->first_quick_scan_conf =
1115 			ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1116 		antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA1;
1117 		break;
1118 	case 0x23: /* LNA1 A+B */
1119 		antcomb->main_conf = ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1120 		antcomb->first_quick_scan_conf =
1121 			ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1122 		antcomb->second_quick_scan_conf = ATH_ANT_DIV_COMB_LNA2;
1123 		break;
1124 	default:
1125 		break;
1126 	}
1127 }
1128 
ath_select_ant_div_from_quick_scan(struct ath_ant_comb * antcomb,struct ath_hw_antcomb_conf * div_ant_conf,int main_rssi_avg,int alt_rssi_avg,int alt_ratio)1129 static void ath_select_ant_div_from_quick_scan(struct ath_ant_comb *antcomb,
1130 				struct ath_hw_antcomb_conf *div_ant_conf,
1131 				int main_rssi_avg, int alt_rssi_avg,
1132 				int alt_ratio)
1133 {
1134 	/* alt_good */
1135 	switch (antcomb->quick_scan_cnt) {
1136 	case 0:
1137 		/* set alt to main, and alt to first conf */
1138 		div_ant_conf->main_lna_conf = antcomb->main_conf;
1139 		div_ant_conf->alt_lna_conf = antcomb->first_quick_scan_conf;
1140 		break;
1141 	case 1:
1142 		/* set alt to main, and alt to first conf */
1143 		div_ant_conf->main_lna_conf = antcomb->main_conf;
1144 		div_ant_conf->alt_lna_conf = antcomb->second_quick_scan_conf;
1145 		antcomb->rssi_first = main_rssi_avg;
1146 		antcomb->rssi_second = alt_rssi_avg;
1147 
1148 		if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) {
1149 			/* main is LNA1 */
1150 			if (ath_is_alt_ant_ratio_better(alt_ratio,
1151 						ATH_ANT_DIV_COMB_LNA1_DELTA_HI,
1152 						ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1153 						main_rssi_avg, alt_rssi_avg,
1154 						antcomb->total_pkt_count))
1155 				antcomb->first_ratio = true;
1156 			else
1157 				antcomb->first_ratio = false;
1158 		} else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2) {
1159 			if (ath_is_alt_ant_ratio_better(alt_ratio,
1160 						ATH_ANT_DIV_COMB_LNA1_DELTA_MID,
1161 						ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1162 						main_rssi_avg, alt_rssi_avg,
1163 						antcomb->total_pkt_count))
1164 				antcomb->first_ratio = true;
1165 			else
1166 				antcomb->first_ratio = false;
1167 		} else {
1168 			if ((((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
1169 			    (alt_rssi_avg > main_rssi_avg +
1170 			    ATH_ANT_DIV_COMB_LNA1_DELTA_HI)) ||
1171 			    (alt_rssi_avg > main_rssi_avg)) &&
1172 			    (antcomb->total_pkt_count > 50))
1173 				antcomb->first_ratio = true;
1174 			else
1175 				antcomb->first_ratio = false;
1176 		}
1177 		break;
1178 	case 2:
1179 		antcomb->alt_good = false;
1180 		antcomb->scan_not_start = false;
1181 		antcomb->scan = false;
1182 		antcomb->rssi_first = main_rssi_avg;
1183 		antcomb->rssi_third = alt_rssi_avg;
1184 
1185 		if (antcomb->second_quick_scan_conf == ATH_ANT_DIV_COMB_LNA1)
1186 			antcomb->rssi_lna1 = alt_rssi_avg;
1187 		else if (antcomb->second_quick_scan_conf ==
1188 			 ATH_ANT_DIV_COMB_LNA2)
1189 			antcomb->rssi_lna2 = alt_rssi_avg;
1190 		else if (antcomb->second_quick_scan_conf ==
1191 			 ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2) {
1192 			if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2)
1193 				antcomb->rssi_lna2 = main_rssi_avg;
1194 			else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1)
1195 				antcomb->rssi_lna1 = main_rssi_avg;
1196 		}
1197 
1198 		if (antcomb->rssi_lna2 > antcomb->rssi_lna1 +
1199 		    ATH_ANT_DIV_COMB_LNA1_LNA2_SWITCH_DELTA)
1200 			div_ant_conf->main_lna_conf = ATH_ANT_DIV_COMB_LNA2;
1201 		else
1202 			div_ant_conf->main_lna_conf = ATH_ANT_DIV_COMB_LNA1;
1203 
1204 		if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) {
1205 			if (ath_is_alt_ant_ratio_better(alt_ratio,
1206 						ATH_ANT_DIV_COMB_LNA1_DELTA_HI,
1207 						ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1208 						main_rssi_avg, alt_rssi_avg,
1209 						antcomb->total_pkt_count))
1210 				antcomb->second_ratio = true;
1211 			else
1212 				antcomb->second_ratio = false;
1213 		} else if (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2) {
1214 			if (ath_is_alt_ant_ratio_better(alt_ratio,
1215 						ATH_ANT_DIV_COMB_LNA1_DELTA_MID,
1216 						ATH_ANT_DIV_COMB_LNA1_DELTA_LOW,
1217 						main_rssi_avg, alt_rssi_avg,
1218 						antcomb->total_pkt_count))
1219 				antcomb->second_ratio = true;
1220 			else
1221 				antcomb->second_ratio = false;
1222 		} else {
1223 			if ((((alt_ratio >= ATH_ANT_DIV_COMB_ALT_ANT_RATIO2) &&
1224 			    (alt_rssi_avg > main_rssi_avg +
1225 			    ATH_ANT_DIV_COMB_LNA1_DELTA_HI)) ||
1226 			    (alt_rssi_avg > main_rssi_avg)) &&
1227 			    (antcomb->total_pkt_count > 50))
1228 				antcomb->second_ratio = true;
1229 			else
1230 				antcomb->second_ratio = false;
1231 		}
1232 
1233 		/* set alt to the conf with maximun ratio */
1234 		if (antcomb->first_ratio && antcomb->second_ratio) {
1235 			if (antcomb->rssi_second > antcomb->rssi_third) {
1236 				/* first alt*/
1237 				if ((antcomb->first_quick_scan_conf ==
1238 				    ATH_ANT_DIV_COMB_LNA1) ||
1239 				    (antcomb->first_quick_scan_conf ==
1240 				    ATH_ANT_DIV_COMB_LNA2))
1241 					/* Set alt LNA1 or LNA2*/
1242 					if (div_ant_conf->main_lna_conf ==
1243 					    ATH_ANT_DIV_COMB_LNA2)
1244 						div_ant_conf->alt_lna_conf =
1245 							ATH_ANT_DIV_COMB_LNA1;
1246 					else
1247 						div_ant_conf->alt_lna_conf =
1248 							ATH_ANT_DIV_COMB_LNA2;
1249 				else
1250 					/* Set alt to A+B or A-B */
1251 					div_ant_conf->alt_lna_conf =
1252 						antcomb->first_quick_scan_conf;
1253 			} else if ((antcomb->second_quick_scan_conf ==
1254 				   ATH_ANT_DIV_COMB_LNA1) ||
1255 				   (antcomb->second_quick_scan_conf ==
1256 				   ATH_ANT_DIV_COMB_LNA2)) {
1257 				/* Set alt LNA1 or LNA2 */
1258 				if (div_ant_conf->main_lna_conf ==
1259 				    ATH_ANT_DIV_COMB_LNA2)
1260 					div_ant_conf->alt_lna_conf =
1261 						ATH_ANT_DIV_COMB_LNA1;
1262 				else
1263 					div_ant_conf->alt_lna_conf =
1264 						ATH_ANT_DIV_COMB_LNA2;
1265 			} else {
1266 				/* Set alt to A+B or A-B */
1267 				div_ant_conf->alt_lna_conf =
1268 					antcomb->second_quick_scan_conf;
1269 			}
1270 		} else if (antcomb->first_ratio) {
1271 			/* first alt */
1272 			if ((antcomb->first_quick_scan_conf ==
1273 			    ATH_ANT_DIV_COMB_LNA1) ||
1274 			    (antcomb->first_quick_scan_conf ==
1275 			    ATH_ANT_DIV_COMB_LNA2))
1276 					/* Set alt LNA1 or LNA2 */
1277 				if (div_ant_conf->main_lna_conf ==
1278 				    ATH_ANT_DIV_COMB_LNA2)
1279 					div_ant_conf->alt_lna_conf =
1280 							ATH_ANT_DIV_COMB_LNA1;
1281 				else
1282 					div_ant_conf->alt_lna_conf =
1283 							ATH_ANT_DIV_COMB_LNA2;
1284 			else
1285 				/* Set alt to A+B or A-B */
1286 				div_ant_conf->alt_lna_conf =
1287 						antcomb->first_quick_scan_conf;
1288 		} else if (antcomb->second_ratio) {
1289 				/* second alt */
1290 			if ((antcomb->second_quick_scan_conf ==
1291 			    ATH_ANT_DIV_COMB_LNA1) ||
1292 			    (antcomb->second_quick_scan_conf ==
1293 			    ATH_ANT_DIV_COMB_LNA2))
1294 				/* Set alt LNA1 or LNA2 */
1295 				if (div_ant_conf->main_lna_conf ==
1296 				    ATH_ANT_DIV_COMB_LNA2)
1297 					div_ant_conf->alt_lna_conf =
1298 						ATH_ANT_DIV_COMB_LNA1;
1299 				else
1300 					div_ant_conf->alt_lna_conf =
1301 						ATH_ANT_DIV_COMB_LNA2;
1302 			else
1303 				/* Set alt to A+B or A-B */
1304 				div_ant_conf->alt_lna_conf =
1305 						antcomb->second_quick_scan_conf;
1306 		} else {
1307 			/* main is largest */
1308 			if ((antcomb->main_conf == ATH_ANT_DIV_COMB_LNA1) ||
1309 			    (antcomb->main_conf == ATH_ANT_DIV_COMB_LNA2))
1310 				/* Set alt LNA1 or LNA2 */
1311 				if (div_ant_conf->main_lna_conf ==
1312 				    ATH_ANT_DIV_COMB_LNA2)
1313 					div_ant_conf->alt_lna_conf =
1314 							ATH_ANT_DIV_COMB_LNA1;
1315 				else
1316 					div_ant_conf->alt_lna_conf =
1317 							ATH_ANT_DIV_COMB_LNA2;
1318 			else
1319 				/* Set alt to A+B or A-B */
1320 				div_ant_conf->alt_lna_conf = antcomb->main_conf;
1321 		}
1322 		break;
1323 	default:
1324 		break;
1325 	}
1326 }
1327 
ath_ant_div_conf_fast_divbias(struct ath_hw_antcomb_conf * ant_conf,struct ath_ant_comb * antcomb,int alt_ratio)1328 static void ath_ant_div_conf_fast_divbias(struct ath_hw_antcomb_conf *ant_conf,
1329 		struct ath_ant_comb *antcomb, int alt_ratio)
1330 {
1331 	if (ant_conf->div_group == 0) {
1332 		/* Adjust the fast_div_bias based on main and alt lna conf */
1333 		switch ((ant_conf->main_lna_conf << 4) |
1334 				ant_conf->alt_lna_conf) {
1335 		case 0x01: /* A-B LNA2 */
1336 			ant_conf->fast_div_bias = 0x3b;
1337 			break;
1338 		case 0x02: /* A-B LNA1 */
1339 			ant_conf->fast_div_bias = 0x3d;
1340 			break;
1341 		case 0x03: /* A-B A+B */
1342 			ant_conf->fast_div_bias = 0x1;
1343 			break;
1344 		case 0x10: /* LNA2 A-B */
1345 			ant_conf->fast_div_bias = 0x7;
1346 			break;
1347 		case 0x12: /* LNA2 LNA1 */
1348 			ant_conf->fast_div_bias = 0x2;
1349 			break;
1350 		case 0x13: /* LNA2 A+B */
1351 			ant_conf->fast_div_bias = 0x7;
1352 			break;
1353 		case 0x20: /* LNA1 A-B */
1354 			ant_conf->fast_div_bias = 0x6;
1355 			break;
1356 		case 0x21: /* LNA1 LNA2 */
1357 			ant_conf->fast_div_bias = 0x0;
1358 			break;
1359 		case 0x23: /* LNA1 A+B */
1360 			ant_conf->fast_div_bias = 0x6;
1361 			break;
1362 		case 0x30: /* A+B A-B */
1363 			ant_conf->fast_div_bias = 0x1;
1364 			break;
1365 		case 0x31: /* A+B LNA2 */
1366 			ant_conf->fast_div_bias = 0x3b;
1367 			break;
1368 		case 0x32: /* A+B LNA1 */
1369 			ant_conf->fast_div_bias = 0x3d;
1370 			break;
1371 		default:
1372 			break;
1373 		}
1374 	} else if (ant_conf->div_group == 1) {
1375 		/* Adjust the fast_div_bias based on main and alt_lna_conf */
1376 		switch ((ant_conf->main_lna_conf << 4) |
1377 			ant_conf->alt_lna_conf) {
1378 		case 0x01: /* A-B LNA2 */
1379 			ant_conf->fast_div_bias = 0x1;
1380 			ant_conf->main_gaintb = 0;
1381 			ant_conf->alt_gaintb = 0;
1382 			break;
1383 		case 0x02: /* A-B LNA1 */
1384 			ant_conf->fast_div_bias = 0x1;
1385 			ant_conf->main_gaintb = 0;
1386 			ant_conf->alt_gaintb = 0;
1387 			break;
1388 		case 0x03: /* A-B A+B */
1389 			ant_conf->fast_div_bias = 0x1;
1390 			ant_conf->main_gaintb = 0;
1391 			ant_conf->alt_gaintb = 0;
1392 			break;
1393 		case 0x10: /* LNA2 A-B */
1394 			if (!(antcomb->scan) &&
1395 			    (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1396 				ant_conf->fast_div_bias = 0x3f;
1397 			else
1398 				ant_conf->fast_div_bias = 0x1;
1399 			ant_conf->main_gaintb = 0;
1400 			ant_conf->alt_gaintb = 0;
1401 			break;
1402 		case 0x12: /* LNA2 LNA1 */
1403 			ant_conf->fast_div_bias = 0x1;
1404 			ant_conf->main_gaintb = 0;
1405 			ant_conf->alt_gaintb = 0;
1406 			break;
1407 		case 0x13: /* LNA2 A+B */
1408 			if (!(antcomb->scan) &&
1409 			    (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1410 				ant_conf->fast_div_bias = 0x3f;
1411 			else
1412 				ant_conf->fast_div_bias = 0x1;
1413 			ant_conf->main_gaintb = 0;
1414 			ant_conf->alt_gaintb = 0;
1415 			break;
1416 		case 0x20: /* LNA1 A-B */
1417 			if (!(antcomb->scan) &&
1418 			    (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1419 				ant_conf->fast_div_bias = 0x3f;
1420 			else
1421 				ant_conf->fast_div_bias = 0x1;
1422 			ant_conf->main_gaintb = 0;
1423 			ant_conf->alt_gaintb = 0;
1424 			break;
1425 		case 0x21: /* LNA1 LNA2 */
1426 			ant_conf->fast_div_bias = 0x1;
1427 			ant_conf->main_gaintb = 0;
1428 			ant_conf->alt_gaintb = 0;
1429 			break;
1430 		case 0x23: /* LNA1 A+B */
1431 			if (!(antcomb->scan) &&
1432 			    (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1433 				ant_conf->fast_div_bias = 0x3f;
1434 			else
1435 				ant_conf->fast_div_bias = 0x1;
1436 			ant_conf->main_gaintb = 0;
1437 			ant_conf->alt_gaintb = 0;
1438 			break;
1439 		case 0x30: /* A+B A-B */
1440 			ant_conf->fast_div_bias = 0x1;
1441 			ant_conf->main_gaintb = 0;
1442 			ant_conf->alt_gaintb = 0;
1443 			break;
1444 		case 0x31: /* A+B LNA2 */
1445 			ant_conf->fast_div_bias = 0x1;
1446 			ant_conf->main_gaintb = 0;
1447 			ant_conf->alt_gaintb = 0;
1448 			break;
1449 		case 0x32: /* A+B LNA1 */
1450 			ant_conf->fast_div_bias = 0x1;
1451 			ant_conf->main_gaintb = 0;
1452 			ant_conf->alt_gaintb = 0;
1453 			break;
1454 		default:
1455 			break;
1456 		}
1457 	} else if (ant_conf->div_group == 2) {
1458 		/* Adjust the fast_div_bias based on main and alt_lna_conf */
1459 		switch ((ant_conf->main_lna_conf << 4) |
1460 				ant_conf->alt_lna_conf) {
1461 		case 0x01: /* A-B LNA2 */
1462 			ant_conf->fast_div_bias = 0x1;
1463 			ant_conf->main_gaintb = 0;
1464 			ant_conf->alt_gaintb = 0;
1465 			break;
1466 		case 0x02: /* A-B LNA1 */
1467 			ant_conf->fast_div_bias = 0x1;
1468 			ant_conf->main_gaintb = 0;
1469 			ant_conf->alt_gaintb = 0;
1470 			break;
1471 		case 0x03: /* A-B A+B */
1472 			ant_conf->fast_div_bias = 0x1;
1473 			ant_conf->main_gaintb = 0;
1474 			ant_conf->alt_gaintb = 0;
1475 			break;
1476 		case 0x10: /* LNA2 A-B */
1477 			if (!(antcomb->scan) &&
1478 				(alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1479 				ant_conf->fast_div_bias = 0x1;
1480 			else
1481 				ant_conf->fast_div_bias = 0x2;
1482 			ant_conf->main_gaintb = 0;
1483 			ant_conf->alt_gaintb = 0;
1484 			break;
1485 		case 0x12: /* LNA2 LNA1 */
1486 			ant_conf->fast_div_bias = 0x1;
1487 			ant_conf->main_gaintb = 0;
1488 			ant_conf->alt_gaintb = 0;
1489 			break;
1490 		case 0x13: /* LNA2 A+B */
1491 			if (!(antcomb->scan) &&
1492 				(alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1493 				ant_conf->fast_div_bias = 0x1;
1494 			else
1495 				ant_conf->fast_div_bias = 0x2;
1496 			ant_conf->main_gaintb = 0;
1497 			ant_conf->alt_gaintb = 0;
1498 			break;
1499 		case 0x20: /* LNA1 A-B */
1500 			if (!(antcomb->scan) &&
1501 				(alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1502 				ant_conf->fast_div_bias = 0x1;
1503 			else
1504 				ant_conf->fast_div_bias = 0x2;
1505 			ant_conf->main_gaintb = 0;
1506 			ant_conf->alt_gaintb = 0;
1507 			break;
1508 		case 0x21: /* LNA1 LNA2 */
1509 			ant_conf->fast_div_bias = 0x1;
1510 			ant_conf->main_gaintb = 0;
1511 			ant_conf->alt_gaintb = 0;
1512 			break;
1513 		case 0x23: /* LNA1 A+B */
1514 			if (!(antcomb->scan) &&
1515 				(alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO))
1516 				ant_conf->fast_div_bias = 0x1;
1517 			else
1518 				ant_conf->fast_div_bias = 0x2;
1519 			ant_conf->main_gaintb = 0;
1520 			ant_conf->alt_gaintb = 0;
1521 			break;
1522 		case 0x30: /* A+B A-B */
1523 			ant_conf->fast_div_bias = 0x1;
1524 			ant_conf->main_gaintb = 0;
1525 			ant_conf->alt_gaintb = 0;
1526 			break;
1527 		case 0x31: /* A+B LNA2 */
1528 			ant_conf->fast_div_bias = 0x1;
1529 			ant_conf->main_gaintb = 0;
1530 			ant_conf->alt_gaintb = 0;
1531 			break;
1532 		case 0x32: /* A+B LNA1 */
1533 			ant_conf->fast_div_bias = 0x1;
1534 			ant_conf->main_gaintb = 0;
1535 			ant_conf->alt_gaintb = 0;
1536 			break;
1537 		default:
1538 			break;
1539 		}
1540 	}
1541 }
1542 
1543 /* Antenna diversity and combining */
ath_ant_comb_scan(struct ath_softc * sc,struct ath_rx_status * rs)1544 static void ath_ant_comb_scan(struct ath_softc *sc, struct ath_rx_status *rs)
1545 {
1546 	struct ath_hw_antcomb_conf div_ant_conf;
1547 	struct ath_ant_comb *antcomb = &sc->ant_comb;
1548 	int alt_ratio = 0, alt_rssi_avg = 0, main_rssi_avg = 0, curr_alt_set;
1549 	int curr_main_set;
1550 	int main_rssi = rs->rs_rssi_ctl0;
1551 	int alt_rssi = rs->rs_rssi_ctl1;
1552 	int rx_ant_conf,  main_ant_conf;
1553 	bool short_scan = false;
1554 
1555 	rx_ant_conf = (rs->rs_rssi_ctl2 >> ATH_ANT_RX_CURRENT_SHIFT) &
1556 		       ATH_ANT_RX_MASK;
1557 	main_ant_conf = (rs->rs_rssi_ctl2 >> ATH_ANT_RX_MAIN_SHIFT) &
1558 			 ATH_ANT_RX_MASK;
1559 
1560 	/* Record packet only when both main_rssi and  alt_rssi is positive */
1561 	if (main_rssi > 0 && alt_rssi > 0) {
1562 		antcomb->total_pkt_count++;
1563 		antcomb->main_total_rssi += main_rssi;
1564 		antcomb->alt_total_rssi  += alt_rssi;
1565 		if (main_ant_conf == rx_ant_conf)
1566 			antcomb->main_recv_cnt++;
1567 		else
1568 			antcomb->alt_recv_cnt++;
1569 	}
1570 
1571 	/* Short scan check */
1572 	if (antcomb->scan && antcomb->alt_good) {
1573 		if (time_after(jiffies, antcomb->scan_start_time +
1574 		    msecs_to_jiffies(ATH_ANT_DIV_COMB_SHORT_SCAN_INTR)))
1575 			short_scan = true;
1576 		else
1577 			if (antcomb->total_pkt_count ==
1578 			    ATH_ANT_DIV_COMB_SHORT_SCAN_PKTCOUNT) {
1579 				alt_ratio = ((antcomb->alt_recv_cnt * 100) /
1580 					    antcomb->total_pkt_count);
1581 				if (alt_ratio < ATH_ANT_DIV_COMB_ALT_ANT_RATIO)
1582 					short_scan = true;
1583 			}
1584 	}
1585 
1586 	if (((antcomb->total_pkt_count < ATH_ANT_DIV_COMB_MAX_PKTCOUNT) ||
1587 	    rs->rs_moreaggr) && !short_scan)
1588 		return;
1589 
1590 	if (antcomb->total_pkt_count) {
1591 		alt_ratio = ((antcomb->alt_recv_cnt * 100) /
1592 			     antcomb->total_pkt_count);
1593 		main_rssi_avg = (antcomb->main_total_rssi /
1594 				 antcomb->total_pkt_count);
1595 		alt_rssi_avg = (antcomb->alt_total_rssi /
1596 				 antcomb->total_pkt_count);
1597 	}
1598 
1599 
1600 	ath9k_hw_antdiv_comb_conf_get(sc->sc_ah, &div_ant_conf);
1601 	curr_alt_set = div_ant_conf.alt_lna_conf;
1602 	curr_main_set = div_ant_conf.main_lna_conf;
1603 
1604 	antcomb->count++;
1605 
1606 	if (antcomb->count == ATH_ANT_DIV_COMB_MAX_COUNT) {
1607 		if (alt_ratio > ATH_ANT_DIV_COMB_ALT_ANT_RATIO) {
1608 			ath_lnaconf_alt_good_scan(antcomb, div_ant_conf,
1609 						  main_rssi_avg);
1610 			antcomb->alt_good = true;
1611 		} else {
1612 			antcomb->alt_good = false;
1613 		}
1614 
1615 		antcomb->count = 0;
1616 		antcomb->scan = true;
1617 		antcomb->scan_not_start = true;
1618 	}
1619 
1620 	if (!antcomb->scan) {
1621 		if (ath_ant_div_comb_alt_check(div_ant_conf.div_group,
1622 					alt_ratio, curr_main_set, curr_alt_set,
1623 					alt_rssi_avg, main_rssi_avg)) {
1624 			if (curr_alt_set == ATH_ANT_DIV_COMB_LNA2) {
1625 				/* Switch main and alt LNA */
1626 				div_ant_conf.main_lna_conf =
1627 						ATH_ANT_DIV_COMB_LNA2;
1628 				div_ant_conf.alt_lna_conf  =
1629 						ATH_ANT_DIV_COMB_LNA1;
1630 			} else if (curr_alt_set == ATH_ANT_DIV_COMB_LNA1) {
1631 				div_ant_conf.main_lna_conf =
1632 						ATH_ANT_DIV_COMB_LNA1;
1633 				div_ant_conf.alt_lna_conf  =
1634 						ATH_ANT_DIV_COMB_LNA2;
1635 			}
1636 
1637 			goto div_comb_done;
1638 		} else if ((curr_alt_set != ATH_ANT_DIV_COMB_LNA1) &&
1639 			   (curr_alt_set != ATH_ANT_DIV_COMB_LNA2)) {
1640 			/* Set alt to another LNA */
1641 			if (curr_main_set == ATH_ANT_DIV_COMB_LNA2)
1642 				div_ant_conf.alt_lna_conf =
1643 						ATH_ANT_DIV_COMB_LNA1;
1644 			else if (curr_main_set == ATH_ANT_DIV_COMB_LNA1)
1645 				div_ant_conf.alt_lna_conf =
1646 						ATH_ANT_DIV_COMB_LNA2;
1647 
1648 			goto div_comb_done;
1649 		}
1650 
1651 		if ((alt_rssi_avg < (main_rssi_avg +
1652 						div_ant_conf.lna1_lna2_delta)))
1653 			goto div_comb_done;
1654 	}
1655 
1656 	if (!antcomb->scan_not_start) {
1657 		switch (curr_alt_set) {
1658 		case ATH_ANT_DIV_COMB_LNA2:
1659 			antcomb->rssi_lna2 = alt_rssi_avg;
1660 			antcomb->rssi_lna1 = main_rssi_avg;
1661 			antcomb->scan = true;
1662 			/* set to A+B */
1663 			div_ant_conf.main_lna_conf =
1664 				ATH_ANT_DIV_COMB_LNA1;
1665 			div_ant_conf.alt_lna_conf  =
1666 				ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1667 			break;
1668 		case ATH_ANT_DIV_COMB_LNA1:
1669 			antcomb->rssi_lna1 = alt_rssi_avg;
1670 			antcomb->rssi_lna2 = main_rssi_avg;
1671 			antcomb->scan = true;
1672 			/* set to A+B */
1673 			div_ant_conf.main_lna_conf = ATH_ANT_DIV_COMB_LNA2;
1674 			div_ant_conf.alt_lna_conf  =
1675 				ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1676 			break;
1677 		case ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2:
1678 			antcomb->rssi_add = alt_rssi_avg;
1679 			antcomb->scan = true;
1680 			/* set to A-B */
1681 			div_ant_conf.alt_lna_conf =
1682 				ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1683 			break;
1684 		case ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2:
1685 			antcomb->rssi_sub = alt_rssi_avg;
1686 			antcomb->scan = false;
1687 			if (antcomb->rssi_lna2 >
1688 			    (antcomb->rssi_lna1 +
1689 			    ATH_ANT_DIV_COMB_LNA1_LNA2_SWITCH_DELTA)) {
1690 				/* use LNA2 as main LNA */
1691 				if ((antcomb->rssi_add > antcomb->rssi_lna1) &&
1692 				    (antcomb->rssi_add > antcomb->rssi_sub)) {
1693 					/* set to A+B */
1694 					div_ant_conf.main_lna_conf =
1695 						ATH_ANT_DIV_COMB_LNA2;
1696 					div_ant_conf.alt_lna_conf  =
1697 						ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1698 				} else if (antcomb->rssi_sub >
1699 					   antcomb->rssi_lna1) {
1700 					/* set to A-B */
1701 					div_ant_conf.main_lna_conf =
1702 						ATH_ANT_DIV_COMB_LNA2;
1703 					div_ant_conf.alt_lna_conf =
1704 						ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1705 				} else {
1706 					/* set to LNA1 */
1707 					div_ant_conf.main_lna_conf =
1708 						ATH_ANT_DIV_COMB_LNA2;
1709 					div_ant_conf.alt_lna_conf =
1710 						ATH_ANT_DIV_COMB_LNA1;
1711 				}
1712 			} else {
1713 				/* use LNA1 as main LNA */
1714 				if ((antcomb->rssi_add > antcomb->rssi_lna2) &&
1715 				    (antcomb->rssi_add > antcomb->rssi_sub)) {
1716 					/* set to A+B */
1717 					div_ant_conf.main_lna_conf =
1718 						ATH_ANT_DIV_COMB_LNA1;
1719 					div_ant_conf.alt_lna_conf  =
1720 						ATH_ANT_DIV_COMB_LNA1_PLUS_LNA2;
1721 				} else if (antcomb->rssi_sub >
1722 					   antcomb->rssi_lna1) {
1723 					/* set to A-B */
1724 					div_ant_conf.main_lna_conf =
1725 						ATH_ANT_DIV_COMB_LNA1;
1726 					div_ant_conf.alt_lna_conf =
1727 						ATH_ANT_DIV_COMB_LNA1_MINUS_LNA2;
1728 				} else {
1729 					/* set to LNA2 */
1730 					div_ant_conf.main_lna_conf =
1731 						ATH_ANT_DIV_COMB_LNA1;
1732 					div_ant_conf.alt_lna_conf =
1733 						ATH_ANT_DIV_COMB_LNA2;
1734 				}
1735 			}
1736 			break;
1737 		default:
1738 			break;
1739 		}
1740 	} else {
1741 		if (!antcomb->alt_good) {
1742 			antcomb->scan_not_start = false;
1743 			/* Set alt to another LNA */
1744 			if (curr_main_set == ATH_ANT_DIV_COMB_LNA2) {
1745 				div_ant_conf.main_lna_conf =
1746 						ATH_ANT_DIV_COMB_LNA2;
1747 				div_ant_conf.alt_lna_conf =
1748 						ATH_ANT_DIV_COMB_LNA1;
1749 			} else if (curr_main_set == ATH_ANT_DIV_COMB_LNA1) {
1750 				div_ant_conf.main_lna_conf =
1751 						ATH_ANT_DIV_COMB_LNA1;
1752 				div_ant_conf.alt_lna_conf =
1753 						ATH_ANT_DIV_COMB_LNA2;
1754 			}
1755 			goto div_comb_done;
1756 		}
1757 	}
1758 
1759 	ath_select_ant_div_from_quick_scan(antcomb, &div_ant_conf,
1760 					   main_rssi_avg, alt_rssi_avg,
1761 					   alt_ratio);
1762 
1763 	antcomb->quick_scan_cnt++;
1764 
1765 div_comb_done:
1766 	ath_ant_div_conf_fast_divbias(&div_ant_conf, antcomb, alt_ratio);
1767 	ath9k_hw_antdiv_comb_conf_set(sc->sc_ah, &div_ant_conf);
1768 
1769 	antcomb->scan_start_time = jiffies;
1770 	antcomb->total_pkt_count = 0;
1771 	antcomb->main_total_rssi = 0;
1772 	antcomb->alt_total_rssi = 0;
1773 	antcomb->main_recv_cnt = 0;
1774 	antcomb->alt_recv_cnt = 0;
1775 }
1776 
ath_rx_tasklet(struct ath_softc * sc,int flush,bool hp)1777 int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
1778 {
1779 	struct ath_buf *bf;
1780 	struct sk_buff *skb = NULL, *requeue_skb, *hdr_skb;
1781 	struct ieee80211_rx_status *rxs;
1782 	struct ath_hw *ah = sc->sc_ah;
1783 	struct ath_common *common = ath9k_hw_common(ah);
1784 	struct ieee80211_hw *hw = sc->hw;
1785 	struct ieee80211_hdr *hdr;
1786 	int retval;
1787 	struct ath_rx_status rs;
1788 	enum ath9k_rx_qtype qtype;
1789 	bool edma = !!(ah->caps.hw_caps & ATH9K_HW_CAP_EDMA);
1790 	int dma_type;
1791 	u8 rx_status_len = ah->caps.rx_status_len;
1792 	u64 tsf = 0;
1793 	u32 tsf_lower = 0;
1794 	unsigned long flags;
1795 
1796 	if (edma)
1797 		dma_type = DMA_BIDIRECTIONAL;
1798 	else
1799 		dma_type = DMA_FROM_DEVICE;
1800 
1801 	qtype = hp ? ATH9K_RX_QUEUE_HP : ATH9K_RX_QUEUE_LP;
1802 	spin_lock_bh(&sc->rx.rxbuflock);
1803 
1804 	tsf = ath9k_hw_gettsf64(ah);
1805 	tsf_lower = tsf & 0xffffffff;
1806 
1807 	do {
1808 		bool decrypt_error = false;
1809 		/* If handling rx interrupt and flush is in progress => exit */
1810 		if ((sc->sc_flags & SC_OP_RXFLUSH) && (flush == 0))
1811 			break;
1812 
1813 		memset(&rs, 0, sizeof(rs));
1814 		if (edma)
1815 			bf = ath_edma_get_next_rx_buf(sc, &rs, qtype);
1816 		else
1817 			bf = ath_get_next_rx_buf(sc, &rs);
1818 
1819 		if (!bf)
1820 			break;
1821 
1822 		skb = bf->bf_mpdu;
1823 		if (!skb)
1824 			continue;
1825 
1826 		/*
1827 		 * Take frame header from the first fragment and RX status from
1828 		 * the last one.
1829 		 */
1830 		if (sc->rx.frag)
1831 			hdr_skb = sc->rx.frag;
1832 		else
1833 			hdr_skb = skb;
1834 
1835 		hdr = (struct ieee80211_hdr *) (hdr_skb->data + rx_status_len);
1836 		rxs = IEEE80211_SKB_RXCB(hdr_skb);
1837 		if (ieee80211_is_beacon(hdr->frame_control) &&
1838 		    !is_zero_ether_addr(common->curbssid) &&
1839 		    !compare_ether_addr(hdr->addr3, common->curbssid))
1840 			rs.is_mybeacon = true;
1841 		else
1842 			rs.is_mybeacon = false;
1843 
1844 		ath_debug_stat_rx(sc, &rs);
1845 
1846 		/*
1847 		 * If we're asked to flush receive queue, directly
1848 		 * chain it back at the queue without processing it.
1849 		 */
1850 		if (sc->sc_flags & SC_OP_RXFLUSH)
1851 			goto requeue_drop_frag;
1852 
1853 		memset(rxs, 0, sizeof(struct ieee80211_rx_status));
1854 
1855 		rxs->mactime = (tsf & ~0xffffffffULL) | rs.rs_tstamp;
1856 		if (rs.rs_tstamp > tsf_lower &&
1857 		    unlikely(rs.rs_tstamp - tsf_lower > 0x10000000))
1858 			rxs->mactime -= 0x100000000ULL;
1859 
1860 		if (rs.rs_tstamp < tsf_lower &&
1861 		    unlikely(tsf_lower - rs.rs_tstamp > 0x10000000))
1862 			rxs->mactime += 0x100000000ULL;
1863 
1864 		retval = ath9k_rx_skb_preprocess(common, hw, hdr, &rs,
1865 						 rxs, &decrypt_error);
1866 		if (retval)
1867 			goto requeue_drop_frag;
1868 
1869 		/* Ensure we always have an skb to requeue once we are done
1870 		 * processing the current buffer's skb */
1871 		requeue_skb = ath_rxbuf_alloc(common, common->rx_bufsize, GFP_ATOMIC);
1872 
1873 		/* If there is no memory we ignore the current RX'd frame,
1874 		 * tell hardware it can give us a new frame using the old
1875 		 * skb and put it at the tail of the sc->rx.rxbuf list for
1876 		 * processing. */
1877 		if (!requeue_skb)
1878 			goto requeue_drop_frag;
1879 
1880 		/* Unmap the frame */
1881 		dma_unmap_single(sc->dev, bf->bf_buf_addr,
1882 				 common->rx_bufsize,
1883 				 dma_type);
1884 
1885 		skb_put(skb, rs.rs_datalen + ah->caps.rx_status_len);
1886 		if (ah->caps.rx_status_len)
1887 			skb_pull(skb, ah->caps.rx_status_len);
1888 
1889 		if (!rs.rs_more)
1890 			ath9k_rx_skb_postprocess(common, hdr_skb, &rs,
1891 						 rxs, decrypt_error);
1892 
1893 		/* We will now give hardware our shiny new allocated skb */
1894 		bf->bf_mpdu = requeue_skb;
1895 		bf->bf_buf_addr = dma_map_single(sc->dev, requeue_skb->data,
1896 						 common->rx_bufsize,
1897 						 dma_type);
1898 		if (unlikely(dma_mapping_error(sc->dev,
1899 			  bf->bf_buf_addr))) {
1900 			dev_kfree_skb_any(requeue_skb);
1901 			bf->bf_mpdu = NULL;
1902 			bf->bf_buf_addr = 0;
1903 			ath_err(common, "dma_mapping_error() on RX\n");
1904 			ieee80211_rx(hw, skb);
1905 			break;
1906 		}
1907 
1908 		if (rs.rs_more) {
1909 			/*
1910 			 * rs_more indicates chained descriptors which can be
1911 			 * used to link buffers together for a sort of
1912 			 * scatter-gather operation.
1913 			 */
1914 			if (sc->rx.frag) {
1915 				/* too many fragments - cannot handle frame */
1916 				dev_kfree_skb_any(sc->rx.frag);
1917 				dev_kfree_skb_any(skb);
1918 				skb = NULL;
1919 			}
1920 			sc->rx.frag = skb;
1921 			goto requeue;
1922 		}
1923 
1924 		if (sc->rx.frag) {
1925 			int space = skb->len - skb_tailroom(hdr_skb);
1926 
1927 			if (pskb_expand_head(hdr_skb, 0, space, GFP_ATOMIC) < 0) {
1928 				dev_kfree_skb(skb);
1929 				goto requeue_drop_frag;
1930 			}
1931 
1932 			sc->rx.frag = NULL;
1933 
1934 			skb_copy_from_linear_data(skb, skb_put(hdr_skb, skb->len),
1935 						  skb->len);
1936 			dev_kfree_skb_any(skb);
1937 			skb = hdr_skb;
1938 		}
1939 
1940 
1941 		if (ah->caps.hw_caps & ATH9K_HW_CAP_ANT_DIV_COMB) {
1942 
1943 			/*
1944 			 * change the default rx antenna if rx diversity
1945 			 * chooses the other antenna 3 times in a row.
1946 			 */
1947 			if (sc->rx.defant != rs.rs_antenna) {
1948 				if (++sc->rx.rxotherant >= 3)
1949 					ath_setdefantenna(sc, rs.rs_antenna);
1950 			} else {
1951 				sc->rx.rxotherant = 0;
1952 			}
1953 
1954 		}
1955 
1956 		if (rxs->flag & RX_FLAG_MMIC_STRIPPED)
1957 			skb_trim(skb, skb->len - 8);
1958 
1959 		spin_lock_irqsave(&sc->sc_pm_lock, flags);
1960 
1961 		if ((sc->ps_flags & (PS_WAIT_FOR_BEACON |
1962 				     PS_WAIT_FOR_CAB |
1963 				     PS_WAIT_FOR_PSPOLL_DATA)) ||
1964 		    ath9k_check_auto_sleep(sc))
1965 			ath_rx_ps(sc, skb, rs.is_mybeacon);
1966 		spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
1967 
1968 		if ((ah->caps.hw_caps & ATH9K_HW_CAP_ANT_DIV_COMB) && sc->ant_rx == 3)
1969 			ath_ant_comb_scan(sc, &rs);
1970 
1971 		ieee80211_rx(hw, skb);
1972 
1973 requeue_drop_frag:
1974 		if (sc->rx.frag) {
1975 			dev_kfree_skb_any(sc->rx.frag);
1976 			sc->rx.frag = NULL;
1977 		}
1978 requeue:
1979 		list_add_tail(&bf->list, &sc->rx.rxbuf);
1980 		if (flush)
1981 			continue;
1982 
1983 		if (edma) {
1984 			ath_rx_edma_buf_link(sc, qtype);
1985 		} else {
1986 			ath_rx_buf_relink(sc, bf);
1987 			ath9k_hw_rxena(ah);
1988 		}
1989 	} while (1);
1990 
1991 	spin_unlock_bh(&sc->rx.rxbuflock);
1992 
1993 	if (!(ah->imask & ATH9K_INT_RXEOL)) {
1994 		ah->imask |= (ATH9K_INT_RXEOL | ATH9K_INT_RXORN);
1995 		ath9k_hw_set_interrupts(ah);
1996 	}
1997 
1998 	return 0;
1999 }
2000