xref: /openbmc/linux/drivers/net/wireless/ath/ath9k/link.c (revision 8fdff1dc)
1 /*
2  * Copyright (c) 2012 Qualcomm Atheros, 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 "ath9k.h"
18 
19 /*
20  * TX polling - checks if the TX engine is stuck somewhere
21  * and issues a chip reset if so.
22  */
23 void ath_tx_complete_poll_work(struct work_struct *work)
24 {
25 	struct ath_softc *sc = container_of(work, struct ath_softc,
26 					    tx_complete_work.work);
27 	struct ath_txq *txq;
28 	int i;
29 	bool needreset = false;
30 
31 	for (i = 0; i < ATH9K_NUM_TX_QUEUES; i++)
32 		if (ATH_TXQ_SETUP(sc, i)) {
33 			txq = &sc->tx.txq[i];
34 			ath_txq_lock(sc, txq);
35 			if (txq->axq_depth) {
36 				if (txq->axq_tx_inprogress) {
37 					needreset = true;
38 					ath_txq_unlock(sc, txq);
39 					break;
40 				} else {
41 					txq->axq_tx_inprogress = true;
42 				}
43 			}
44 			ath_txq_unlock_complete(sc, txq);
45 		}
46 
47 	if (needreset) {
48 		ath_dbg(ath9k_hw_common(sc->sc_ah), RESET,
49 			"tx hung, resetting the chip\n");
50 		ath9k_queue_reset(sc, RESET_TYPE_TX_HANG);
51 		return;
52 	}
53 
54 	ieee80211_queue_delayed_work(sc->hw, &sc->tx_complete_work,
55 				     msecs_to_jiffies(ATH_TX_COMPLETE_POLL_INT));
56 }
57 
58 /*
59  * Checks if the BB/MAC is hung.
60  */
61 void ath_hw_check(struct work_struct *work)
62 {
63 	struct ath_softc *sc = container_of(work, struct ath_softc, hw_check_work);
64 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
65 	unsigned long flags;
66 	int busy;
67 	u8 is_alive, nbeacon = 1;
68 	enum ath_reset_type type;
69 
70 	ath9k_ps_wakeup(sc);
71 	is_alive = ath9k_hw_check_alive(sc->sc_ah);
72 
73 	if (is_alive && !AR_SREV_9300(sc->sc_ah))
74 		goto out;
75 	else if (!is_alive && AR_SREV_9300(sc->sc_ah)) {
76 		ath_dbg(common, RESET,
77 			"DCU stuck is detected. Schedule chip reset\n");
78 		type = RESET_TYPE_MAC_HANG;
79 		goto sched_reset;
80 	}
81 
82 	spin_lock_irqsave(&common->cc_lock, flags);
83 	busy = ath_update_survey_stats(sc);
84 	spin_unlock_irqrestore(&common->cc_lock, flags);
85 
86 	ath_dbg(common, RESET, "Possible baseband hang, busy=%d (try %d)\n",
87 		busy, sc->hw_busy_count + 1);
88 	if (busy >= 99) {
89 		if (++sc->hw_busy_count >= 3) {
90 			type = RESET_TYPE_BB_HANG;
91 			goto sched_reset;
92 		}
93 	} else if (busy >= 0) {
94 		sc->hw_busy_count = 0;
95 		nbeacon = 3;
96 	}
97 
98 	ath_start_rx_poll(sc, nbeacon);
99 	goto out;
100 
101 sched_reset:
102 	ath9k_queue_reset(sc, type);
103 out:
104 	ath9k_ps_restore(sc);
105 }
106 
107 /*
108  * PLL-WAR for AR9485/AR9340
109  */
110 static bool ath_hw_pll_rx_hang_check(struct ath_softc *sc, u32 pll_sqsum)
111 {
112 	static int count;
113 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
114 
115 	if (pll_sqsum >= 0x40000) {
116 		count++;
117 		if (count == 3) {
118 			ath_dbg(common, RESET, "PLL WAR, resetting the chip\n");
119 			ath9k_queue_reset(sc, RESET_TYPE_PLL_HANG);
120 			count = 0;
121 			return true;
122 		}
123 	} else {
124 		count = 0;
125 	}
126 
127 	return false;
128 }
129 
130 void ath_hw_pll_work(struct work_struct *work)
131 {
132 	u32 pll_sqsum;
133 	struct ath_softc *sc = container_of(work, struct ath_softc,
134 					    hw_pll_work.work);
135 	/*
136 	 * ensure that the PLL WAR is executed only
137 	 * after the STA is associated (or) if the
138 	 * beaconing had started in interfaces that
139 	 * uses beacons.
140 	 */
141 	if (!test_bit(SC_OP_BEACONS, &sc->sc_flags))
142 		return;
143 
144 	ath9k_ps_wakeup(sc);
145 	pll_sqsum = ar9003_get_pll_sqsum_dvc(sc->sc_ah);
146 	ath9k_ps_restore(sc);
147 	if (ath_hw_pll_rx_hang_check(sc, pll_sqsum))
148 		return;
149 
150 	ieee80211_queue_delayed_work(sc->hw, &sc->hw_pll_work,
151 				     msecs_to_jiffies(ATH_PLL_WORK_INTERVAL));
152 }
153 
154 /*
155  * RX Polling - monitors baseband hangs.
156  */
157 void ath_start_rx_poll(struct ath_softc *sc, u8 nbeacon)
158 {
159 	if (!AR_SREV_9300(sc->sc_ah))
160 		return;
161 
162 	if (!test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags))
163 		return;
164 
165 	mod_timer(&sc->rx_poll_timer, jiffies + msecs_to_jiffies
166 		  (nbeacon * sc->cur_beacon_conf.beacon_interval));
167 }
168 
169 void ath_rx_poll(unsigned long data)
170 {
171 	struct ath_softc *sc = (struct ath_softc *)data;
172 
173 	ieee80211_queue_work(sc->hw, &sc->hw_check_work);
174 }
175 
176 /*
177  * PA Pre-distortion.
178  */
179 static void ath_paprd_activate(struct ath_softc *sc)
180 {
181 	struct ath_hw *ah = sc->sc_ah;
182 	struct ath_common *common = ath9k_hw_common(ah);
183 	struct ath9k_hw_cal_data *caldata = ah->caldata;
184 	int chain;
185 
186 	if (!caldata || !caldata->paprd_done) {
187 		ath_dbg(common, CALIBRATE, "Failed to activate PAPRD\n");
188 		return;
189 	}
190 
191 	ar9003_paprd_enable(ah, false);
192 	for (chain = 0; chain < AR9300_MAX_CHAINS; chain++) {
193 		if (!(ah->txchainmask & BIT(chain)))
194 			continue;
195 
196 		ar9003_paprd_populate_single_table(ah, caldata, chain);
197 	}
198 
199 	ath_dbg(common, CALIBRATE, "Activating PAPRD\n");
200 	ar9003_paprd_enable(ah, true);
201 }
202 
203 static bool ath_paprd_send_frame(struct ath_softc *sc, struct sk_buff *skb, int chain)
204 {
205 	struct ieee80211_hw *hw = sc->hw;
206 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
207 	struct ath_hw *ah = sc->sc_ah;
208 	struct ath_common *common = ath9k_hw_common(ah);
209 	struct ath_tx_control txctl;
210 	int time_left;
211 
212 	memset(&txctl, 0, sizeof(txctl));
213 	txctl.txq = sc->tx.txq_map[IEEE80211_AC_BE];
214 
215 	memset(tx_info, 0, sizeof(*tx_info));
216 	tx_info->band = hw->conf.channel->band;
217 	tx_info->flags |= IEEE80211_TX_CTL_NO_ACK;
218 	tx_info->control.rates[0].idx = 0;
219 	tx_info->control.rates[0].count = 1;
220 	tx_info->control.rates[0].flags = IEEE80211_TX_RC_MCS;
221 	tx_info->control.rates[1].idx = -1;
222 
223 	init_completion(&sc->paprd_complete);
224 	txctl.paprd = BIT(chain);
225 
226 	if (ath_tx_start(hw, skb, &txctl) != 0) {
227 		ath_dbg(common, CALIBRATE, "PAPRD TX failed\n");
228 		dev_kfree_skb_any(skb);
229 		return false;
230 	}
231 
232 	time_left = wait_for_completion_timeout(&sc->paprd_complete,
233 			msecs_to_jiffies(ATH_PAPRD_TIMEOUT));
234 
235 	if (!time_left)
236 		ath_dbg(common, CALIBRATE,
237 			"Timeout waiting for paprd training on TX chain %d\n",
238 			chain);
239 
240 	return !!time_left;
241 }
242 
243 void ath_paprd_calibrate(struct work_struct *work)
244 {
245 	struct ath_softc *sc = container_of(work, struct ath_softc, paprd_work);
246 	struct ieee80211_hw *hw = sc->hw;
247 	struct ath_hw *ah = sc->sc_ah;
248 	struct ieee80211_hdr *hdr;
249 	struct sk_buff *skb = NULL;
250 	struct ath9k_hw_cal_data *caldata = ah->caldata;
251 	struct ath_common *common = ath9k_hw_common(ah);
252 	int ftype;
253 	int chain_ok = 0;
254 	int chain;
255 	int len = 1800;
256 	int ret;
257 
258 	if (!caldata || !caldata->paprd_packet_sent || caldata->paprd_done) {
259 		ath_dbg(common, CALIBRATE, "Skipping PAPRD calibration\n");
260 		return;
261 	}
262 
263 	ath9k_ps_wakeup(sc);
264 
265 	if (ar9003_paprd_init_table(ah) < 0)
266 		goto fail_paprd;
267 
268 	skb = alloc_skb(len, GFP_KERNEL);
269 	if (!skb)
270 		goto fail_paprd;
271 
272 	skb_put(skb, len);
273 	memset(skb->data, 0, len);
274 	hdr = (struct ieee80211_hdr *)skb->data;
275 	ftype = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC;
276 	hdr->frame_control = cpu_to_le16(ftype);
277 	hdr->duration_id = cpu_to_le16(10);
278 	memcpy(hdr->addr1, hw->wiphy->perm_addr, ETH_ALEN);
279 	memcpy(hdr->addr2, hw->wiphy->perm_addr, ETH_ALEN);
280 	memcpy(hdr->addr3, hw->wiphy->perm_addr, ETH_ALEN);
281 
282 	for (chain = 0; chain < AR9300_MAX_CHAINS; chain++) {
283 		if (!(ah->txchainmask & BIT(chain)))
284 			continue;
285 
286 		chain_ok = 0;
287 		ar9003_paprd_setup_gain_table(ah, chain);
288 
289 		ath_dbg(common, CALIBRATE,
290 			"Sending PAPRD training frame on chain %d\n", chain);
291 		if (!ath_paprd_send_frame(sc, skb, chain))
292 			goto fail_paprd;
293 
294 		if (!ar9003_paprd_is_done(ah)) {
295 			ath_dbg(common, CALIBRATE,
296 				"PAPRD not yet done on chain %d\n", chain);
297 			break;
298 		}
299 
300 		ret = ar9003_paprd_create_curve(ah, caldata, chain);
301 		if (ret == -EINPROGRESS) {
302 			ath_dbg(common, CALIBRATE,
303 				"PAPRD curve on chain %d needs to be re-trained\n",
304 				chain);
305 			break;
306 		} else if (ret) {
307 			ath_dbg(common, CALIBRATE,
308 				"PAPRD create curve failed on chain %d\n",
309 				chain);
310 			break;
311 		}
312 
313 		chain_ok = 1;
314 	}
315 	kfree_skb(skb);
316 
317 	if (chain_ok) {
318 		caldata->paprd_done = true;
319 		ath_paprd_activate(sc);
320 	}
321 
322 fail_paprd:
323 	ath9k_ps_restore(sc);
324 }
325 
326 /*
327  *  ANI performs periodic noise floor calibration
328  *  that is used to adjust and optimize the chip performance.  This
329  *  takes environmental changes (location, temperature) into account.
330  *  When the task is complete, it reschedules itself depending on the
331  *  appropriate interval that was calculated.
332  */
333 void ath_ani_calibrate(unsigned long data)
334 {
335 	struct ath_softc *sc = (struct ath_softc *)data;
336 	struct ath_hw *ah = sc->sc_ah;
337 	struct ath_common *common = ath9k_hw_common(ah);
338 	bool longcal = false;
339 	bool shortcal = false;
340 	bool aniflag = false;
341 	unsigned int timestamp = jiffies_to_msecs(jiffies);
342 	u32 cal_interval, short_cal_interval, long_cal_interval;
343 	unsigned long flags;
344 
345 	if (ah->caldata && ah->caldata->nfcal_interference)
346 		long_cal_interval = ATH_LONG_CALINTERVAL_INT;
347 	else
348 		long_cal_interval = ATH_LONG_CALINTERVAL;
349 
350 	short_cal_interval = (ah->opmode == NL80211_IFTYPE_AP) ?
351 		ATH_AP_SHORT_CALINTERVAL : ATH_STA_SHORT_CALINTERVAL;
352 
353 	/* Only calibrate if awake */
354 	if (sc->sc_ah->power_mode != ATH9K_PM_AWAKE) {
355 		if (++ah->ani_skip_count >= ATH_ANI_MAX_SKIP_COUNT) {
356 			spin_lock_irqsave(&sc->sc_pm_lock, flags);
357 			sc->ps_flags |= PS_WAIT_FOR_ANI;
358 			spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
359 		}
360 		goto set_timer;
361 	}
362 	ah->ani_skip_count = 0;
363 	spin_lock_irqsave(&sc->sc_pm_lock, flags);
364 	sc->ps_flags &= ~PS_WAIT_FOR_ANI;
365 	spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
366 
367 	ath9k_ps_wakeup(sc);
368 
369 	/* Long calibration runs independently of short calibration. */
370 	if ((timestamp - common->ani.longcal_timer) >= long_cal_interval) {
371 		longcal = true;
372 		common->ani.longcal_timer = timestamp;
373 	}
374 
375 	/* Short calibration applies only while caldone is false */
376 	if (!common->ani.caldone) {
377 		if ((timestamp - common->ani.shortcal_timer) >= short_cal_interval) {
378 			shortcal = true;
379 			common->ani.shortcal_timer = timestamp;
380 			common->ani.resetcal_timer = timestamp;
381 		}
382 	} else {
383 		if ((timestamp - common->ani.resetcal_timer) >=
384 		    ATH_RESTART_CALINTERVAL) {
385 			common->ani.caldone = ath9k_hw_reset_calvalid(ah);
386 			if (common->ani.caldone)
387 				common->ani.resetcal_timer = timestamp;
388 		}
389 	}
390 
391 	/* Verify whether we must check ANI */
392 	if (sc->sc_ah->config.enable_ani
393 	    && (timestamp - common->ani.checkani_timer) >=
394 	    ah->config.ani_poll_interval) {
395 		aniflag = true;
396 		common->ani.checkani_timer = timestamp;
397 	}
398 
399 	/* Call ANI routine if necessary */
400 	if (aniflag) {
401 		spin_lock_irqsave(&common->cc_lock, flags);
402 		ath9k_hw_ani_monitor(ah, ah->curchan);
403 		ath_update_survey_stats(sc);
404 		spin_unlock_irqrestore(&common->cc_lock, flags);
405 	}
406 
407 	/* Perform calibration if necessary */
408 	if (longcal || shortcal) {
409 		common->ani.caldone =
410 			ath9k_hw_calibrate(ah, ah->curchan,
411 					   ah->rxchainmask, longcal);
412 	}
413 
414 	ath_dbg(common, ANI,
415 		"Calibration @%lu finished: %s %s %s, caldone: %s\n",
416 		jiffies,
417 		longcal ? "long" : "", shortcal ? "short" : "",
418 		aniflag ? "ani" : "", common->ani.caldone ? "true" : "false");
419 
420 	ath9k_debug_samp_bb_mac(sc);
421 	ath9k_ps_restore(sc);
422 
423 set_timer:
424 	/*
425 	* Set timer interval based on previous results.
426 	* The interval must be the shortest necessary to satisfy ANI,
427 	* short calibration and long calibration.
428 	*/
429 	cal_interval = ATH_LONG_CALINTERVAL;
430 	if (sc->sc_ah->config.enable_ani)
431 		cal_interval = min(cal_interval,
432 				   (u32)ah->config.ani_poll_interval);
433 	if (!common->ani.caldone)
434 		cal_interval = min(cal_interval, (u32)short_cal_interval);
435 
436 	mod_timer(&common->ani.timer, jiffies + msecs_to_jiffies(cal_interval));
437 
438 	if (ar9003_is_paprd_enabled(ah) && ah->caldata) {
439 		if (!ah->caldata->paprd_done) {
440 			ieee80211_queue_work(sc->hw, &sc->paprd_work);
441 		} else if (!ah->paprd_table_write_done) {
442 			ath9k_ps_wakeup(sc);
443 			ath_paprd_activate(sc);
444 			ath9k_ps_restore(sc);
445 		}
446 	}
447 }
448 
449 void ath_start_ani(struct ath_softc *sc)
450 {
451 	struct ath_hw *ah = sc->sc_ah;
452 	struct ath_common *common = ath9k_hw_common(ah);
453 	unsigned long timestamp = jiffies_to_msecs(jiffies);
454 
455 	if (common->disable_ani ||
456 	    !test_bit(SC_OP_ANI_RUN, &sc->sc_flags) ||
457 	    (sc->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL))
458 		return;
459 
460 	common->ani.longcal_timer = timestamp;
461 	common->ani.shortcal_timer = timestamp;
462 	common->ani.checkani_timer = timestamp;
463 
464 	ath_dbg(common, ANI, "Starting ANI\n");
465 	mod_timer(&common->ani.timer,
466 		  jiffies + msecs_to_jiffies((u32)ah->config.ani_poll_interval));
467 }
468 
469 void ath_stop_ani(struct ath_softc *sc)
470 {
471 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
472 
473 	ath_dbg(common, ANI, "Stopping ANI\n");
474 	del_timer_sync(&common->ani.timer);
475 }
476 
477 void ath_check_ani(struct ath_softc *sc)
478 {
479 	struct ath_hw *ah = sc->sc_ah;
480 	struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
481 
482 	/*
483 	 * Check for the various conditions in which ANI has to
484 	 * be stopped.
485 	 */
486 	if (ah->opmode == NL80211_IFTYPE_ADHOC) {
487 		if (!cur_conf->enable_beacon)
488 			goto stop_ani;
489 	} else if (ah->opmode == NL80211_IFTYPE_AP) {
490 		if (!cur_conf->enable_beacon) {
491 			/*
492 			 * Disable ANI only when there are no
493 			 * associated stations.
494 			 */
495 			if (!test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags))
496 				goto stop_ani;
497 		}
498 	} else if (ah->opmode == NL80211_IFTYPE_STATION) {
499 		if (!test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags))
500 			goto stop_ani;
501 	}
502 
503 	if (!test_bit(SC_OP_ANI_RUN, &sc->sc_flags)) {
504 		set_bit(SC_OP_ANI_RUN, &sc->sc_flags);
505 		ath_start_ani(sc);
506 	}
507 
508 	return;
509 
510 stop_ani:
511 	clear_bit(SC_OP_ANI_RUN, &sc->sc_flags);
512 	ath_stop_ani(sc);
513 }
514 
515 void ath_update_survey_nf(struct ath_softc *sc, int channel)
516 {
517 	struct ath_hw *ah = sc->sc_ah;
518 	struct ath9k_channel *chan = &ah->channels[channel];
519 	struct survey_info *survey = &sc->survey[channel];
520 
521 	if (chan->noisefloor) {
522 		survey->filled |= SURVEY_INFO_NOISE_DBM;
523 		survey->noise = ath9k_hw_getchan_noise(ah, chan);
524 	}
525 }
526 
527 /*
528  * Updates the survey statistics and returns the busy time since last
529  * update in %, if the measurement duration was long enough for the
530  * result to be useful, -1 otherwise.
531  */
532 int ath_update_survey_stats(struct ath_softc *sc)
533 {
534 	struct ath_hw *ah = sc->sc_ah;
535 	struct ath_common *common = ath9k_hw_common(ah);
536 	int pos = ah->curchan - &ah->channels[0];
537 	struct survey_info *survey = &sc->survey[pos];
538 	struct ath_cycle_counters *cc = &common->cc_survey;
539 	unsigned int div = common->clockrate * 1000;
540 	int ret = 0;
541 
542 	if (!ah->curchan)
543 		return -1;
544 
545 	if (ah->power_mode == ATH9K_PM_AWAKE)
546 		ath_hw_cycle_counters_update(common);
547 
548 	if (cc->cycles > 0) {
549 		survey->filled |= SURVEY_INFO_CHANNEL_TIME |
550 			SURVEY_INFO_CHANNEL_TIME_BUSY |
551 			SURVEY_INFO_CHANNEL_TIME_RX |
552 			SURVEY_INFO_CHANNEL_TIME_TX;
553 		survey->channel_time += cc->cycles / div;
554 		survey->channel_time_busy += cc->rx_busy / div;
555 		survey->channel_time_rx += cc->rx_frame / div;
556 		survey->channel_time_tx += cc->tx_frame / div;
557 	}
558 
559 	if (cc->cycles < div)
560 		return -1;
561 
562 	if (cc->cycles > 0)
563 		ret = cc->rx_busy * 100 / cc->cycles;
564 
565 	memset(cc, 0, sizeof(*cc));
566 
567 	ath_update_survey_nf(sc, pos);
568 
569 	return ret;
570 }
571