xref: /linux/drivers/net/wireless/ath/ath9k/link.c (revision 37744feebc086908fd89760650f458ab19071750)
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 static bool ath_tx_complete_check(struct ath_softc *sc)
24 {
25 	struct ath_txq *txq;
26 	int i;
27 
28 	if (sc->tx99_state)
29 		return true;
30 
31 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
32 		txq = sc->tx.txq_map[i];
33 
34 		ath_txq_lock(sc, txq);
35 		if (txq->axq_depth) {
36 			if (txq->axq_tx_inprogress) {
37 				ath_txq_unlock(sc, txq);
38 				goto reset;
39 			}
40 
41 			txq->axq_tx_inprogress = true;
42 		}
43 		ath_txq_unlock(sc, txq);
44 	}
45 
46 	return true;
47 
48 reset:
49 	ath_dbg(ath9k_hw_common(sc->sc_ah), RESET,
50 		"tx hung, resetting the chip\n");
51 	ath9k_queue_reset(sc, RESET_TYPE_TX_HANG);
52 	return false;
53 
54 }
55 
56 void ath_hw_check_work(struct work_struct *work)
57 {
58 	struct ath_softc *sc = container_of(work, struct ath_softc,
59 					    hw_check_work.work);
60 
61 	if (!ath_hw_check(sc) ||
62 	    !ath_tx_complete_check(sc))
63 		return;
64 
65 	ieee80211_queue_delayed_work(sc->hw, &sc->hw_check_work,
66 				     msecs_to_jiffies(ATH_HW_CHECK_POLL_INT));
67 }
68 
69 /*
70  * Checks if the BB/MAC is hung.
71  */
72 bool ath_hw_check(struct ath_softc *sc)
73 {
74 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
75 	enum ath_reset_type type;
76 	bool is_alive;
77 
78 	ath9k_ps_wakeup(sc);
79 
80 	is_alive = ath9k_hw_check_alive(sc->sc_ah);
81 
82 	if (!is_alive) {
83 		ath_dbg(common, RESET,
84 			"HW hang detected, schedule chip reset\n");
85 		type = RESET_TYPE_MAC_HANG;
86 		ath9k_queue_reset(sc, type);
87 	}
88 
89 	ath9k_ps_restore(sc);
90 
91 	return is_alive;
92 }
93 
94 /*
95  * PLL-WAR for AR9485/AR9340
96  */
97 static bool ath_hw_pll_rx_hang_check(struct ath_softc *sc, u32 pll_sqsum)
98 {
99 	static int count;
100 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
101 
102 	if (pll_sqsum >= 0x40000) {
103 		count++;
104 		if (count == 3) {
105 			ath_dbg(common, RESET, "PLL WAR, resetting the chip\n");
106 			ath9k_queue_reset(sc, RESET_TYPE_PLL_HANG);
107 			count = 0;
108 			return true;
109 		}
110 	} else {
111 		count = 0;
112 	}
113 
114 	return false;
115 }
116 
117 void ath_hw_pll_work(struct work_struct *work)
118 {
119 	u32 pll_sqsum;
120 	struct ath_softc *sc = container_of(work, struct ath_softc,
121 					    hw_pll_work.work);
122 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
123 	/*
124 	 * ensure that the PLL WAR is executed only
125 	 * after the STA is associated (or) if the
126 	 * beaconing had started in interfaces that
127 	 * uses beacons.
128 	 */
129 	if (!test_bit(ATH_OP_BEACONS, &common->op_flags))
130 		return;
131 
132 	if (sc->tx99_state)
133 		return;
134 
135 	ath9k_ps_wakeup(sc);
136 	pll_sqsum = ar9003_get_pll_sqsum_dvc(sc->sc_ah);
137 	ath9k_ps_restore(sc);
138 	if (ath_hw_pll_rx_hang_check(sc, pll_sqsum))
139 		return;
140 
141 	ieee80211_queue_delayed_work(sc->hw, &sc->hw_pll_work,
142 				     msecs_to_jiffies(ATH_PLL_WORK_INTERVAL));
143 }
144 
145 /*
146  * PA Pre-distortion.
147  */
148 static void ath_paprd_activate(struct ath_softc *sc)
149 {
150 	struct ath_hw *ah = sc->sc_ah;
151 	struct ath_common *common = ath9k_hw_common(ah);
152 	struct ath9k_hw_cal_data *caldata = ah->caldata;
153 	int chain;
154 
155 	if (!caldata || !test_bit(PAPRD_DONE, &caldata->cal_flags)) {
156 		ath_dbg(common, CALIBRATE, "Failed to activate PAPRD\n");
157 		return;
158 	}
159 
160 	ar9003_paprd_enable(ah, false);
161 	for (chain = 0; chain < AR9300_MAX_CHAINS; chain++) {
162 		if (!(ah->txchainmask & BIT(chain)))
163 			continue;
164 
165 		ar9003_paprd_populate_single_table(ah, caldata, chain);
166 	}
167 
168 	ath_dbg(common, CALIBRATE, "Activating PAPRD\n");
169 	ar9003_paprd_enable(ah, true);
170 }
171 
172 static bool ath_paprd_send_frame(struct ath_softc *sc, struct sk_buff *skb, int chain)
173 {
174 	struct ieee80211_hw *hw = sc->hw;
175 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
176 	struct ath_hw *ah = sc->sc_ah;
177 	struct ath_common *common = ath9k_hw_common(ah);
178 	struct ath_tx_control txctl;
179 	unsigned long time_left;
180 
181 	memset(&txctl, 0, sizeof(txctl));
182 	txctl.txq = sc->tx.txq_map[IEEE80211_AC_BE];
183 
184 	memset(tx_info, 0, sizeof(*tx_info));
185 	tx_info->band = sc->cur_chandef.chan->band;
186 	tx_info->flags |= IEEE80211_TX_CTL_NO_ACK;
187 	tx_info->control.rates[0].idx = 0;
188 	tx_info->control.rates[0].count = 1;
189 	tx_info->control.rates[0].flags = IEEE80211_TX_RC_MCS;
190 	tx_info->control.rates[1].idx = -1;
191 
192 	init_completion(&sc->paprd_complete);
193 	txctl.paprd = BIT(chain);
194 
195 	if (ath_tx_start(hw, skb, &txctl) != 0) {
196 		ath_dbg(common, CALIBRATE, "PAPRD TX failed\n");
197 		dev_kfree_skb_any(skb);
198 		return false;
199 	}
200 
201 	time_left = wait_for_completion_timeout(&sc->paprd_complete,
202 			msecs_to_jiffies(ATH_PAPRD_TIMEOUT));
203 
204 	if (!time_left)
205 		ath_dbg(common, CALIBRATE,
206 			"Timeout waiting for paprd training on TX chain %d\n",
207 			chain);
208 
209 	return !!time_left;
210 }
211 
212 void ath_paprd_calibrate(struct work_struct *work)
213 {
214 	struct ath_softc *sc = container_of(work, struct ath_softc, paprd_work);
215 	struct ieee80211_hw *hw = sc->hw;
216 	struct ath_hw *ah = sc->sc_ah;
217 	struct ieee80211_hdr *hdr;
218 	struct sk_buff *skb = NULL;
219 	struct ath9k_hw_cal_data *caldata = ah->caldata;
220 	struct ath_common *common = ath9k_hw_common(ah);
221 	int ftype;
222 	int chain_ok = 0;
223 	int chain;
224 	int len = 1800;
225 	int ret;
226 
227 	if (!caldata ||
228 	    !test_bit(PAPRD_PACKET_SENT, &caldata->cal_flags) ||
229 	    test_bit(PAPRD_DONE, &caldata->cal_flags)) {
230 		ath_dbg(common, CALIBRATE, "Skipping PAPRD calibration\n");
231 		return;
232 	}
233 
234 	ath9k_ps_wakeup(sc);
235 
236 	if (ar9003_paprd_init_table(ah) < 0)
237 		goto fail_paprd;
238 
239 	skb = alloc_skb(len, GFP_KERNEL);
240 	if (!skb)
241 		goto fail_paprd;
242 
243 	skb_put(skb, len);
244 	memset(skb->data, 0, len);
245 	hdr = (struct ieee80211_hdr *)skb->data;
246 	ftype = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC;
247 	hdr->frame_control = cpu_to_le16(ftype);
248 	hdr->duration_id = cpu_to_le16(10);
249 	memcpy(hdr->addr1, hw->wiphy->perm_addr, ETH_ALEN);
250 	memcpy(hdr->addr2, hw->wiphy->perm_addr, ETH_ALEN);
251 	memcpy(hdr->addr3, hw->wiphy->perm_addr, ETH_ALEN);
252 
253 	for (chain = 0; chain < AR9300_MAX_CHAINS; chain++) {
254 		if (!(ah->txchainmask & BIT(chain)))
255 			continue;
256 
257 		chain_ok = 0;
258 		ar9003_paprd_setup_gain_table(ah, chain);
259 
260 		ath_dbg(common, CALIBRATE,
261 			"Sending PAPRD training frame on chain %d\n", chain);
262 		if (!ath_paprd_send_frame(sc, skb, chain))
263 			goto fail_paprd;
264 
265 		if (!ar9003_paprd_is_done(ah)) {
266 			ath_dbg(common, CALIBRATE,
267 				"PAPRD not yet done on chain %d\n", chain);
268 			break;
269 		}
270 
271 		ret = ar9003_paprd_create_curve(ah, caldata, chain);
272 		if (ret == -EINPROGRESS) {
273 			ath_dbg(common, CALIBRATE,
274 				"PAPRD curve on chain %d needs to be re-trained\n",
275 				chain);
276 			break;
277 		} else if (ret) {
278 			ath_dbg(common, CALIBRATE,
279 				"PAPRD create curve failed on chain %d\n",
280 				chain);
281 			break;
282 		}
283 
284 		chain_ok = 1;
285 	}
286 	kfree_skb(skb);
287 
288 	if (chain_ok) {
289 		set_bit(PAPRD_DONE, &caldata->cal_flags);
290 		ath_paprd_activate(sc);
291 	}
292 
293 fail_paprd:
294 	ath9k_ps_restore(sc);
295 }
296 
297 /*
298  *  ANI performs periodic noise floor calibration
299  *  that is used to adjust and optimize the chip performance.  This
300  *  takes environmental changes (location, temperature) into account.
301  *  When the task is complete, it reschedules itself depending on the
302  *  appropriate interval that was calculated.
303  */
304 void ath_ani_calibrate(struct timer_list *t)
305 {
306 	struct ath_common *common = from_timer(common, t, ani.timer);
307 	struct ath_softc *sc = (struct ath_softc *)common->priv;
308 	struct ath_hw *ah = sc->sc_ah;
309 	bool longcal = false;
310 	bool shortcal = false;
311 	bool aniflag = false;
312 	unsigned int timestamp = jiffies_to_msecs(jiffies);
313 	u32 cal_interval, short_cal_interval, long_cal_interval;
314 	unsigned long flags;
315 
316 	if (ah->caldata && test_bit(NFCAL_INTF, &ah->caldata->cal_flags))
317 		long_cal_interval = ATH_LONG_CALINTERVAL_INT;
318 	else
319 		long_cal_interval = ATH_LONG_CALINTERVAL;
320 
321 	short_cal_interval = (ah->opmode == NL80211_IFTYPE_AP) ?
322 		ATH_AP_SHORT_CALINTERVAL : ATH_STA_SHORT_CALINTERVAL;
323 
324 	/* Only calibrate if awake */
325 	if (sc->sc_ah->power_mode != ATH9K_PM_AWAKE) {
326 		if (++ah->ani_skip_count >= ATH_ANI_MAX_SKIP_COUNT) {
327 			spin_lock_irqsave(&sc->sc_pm_lock, flags);
328 			sc->ps_flags |= PS_WAIT_FOR_ANI;
329 			spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
330 		}
331 		goto set_timer;
332 	}
333 	ah->ani_skip_count = 0;
334 	spin_lock_irqsave(&sc->sc_pm_lock, flags);
335 	sc->ps_flags &= ~PS_WAIT_FOR_ANI;
336 	spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
337 
338 	ath9k_ps_wakeup(sc);
339 
340 	/* Long calibration runs independently of short calibration. */
341 	if ((timestamp - common->ani.longcal_timer) >= long_cal_interval) {
342 		longcal = true;
343 		common->ani.longcal_timer = timestamp;
344 	}
345 
346 	/* Short calibration applies only while caldone is false */
347 	if (!common->ani.caldone) {
348 		if ((timestamp - common->ani.shortcal_timer) >= short_cal_interval) {
349 			shortcal = true;
350 			common->ani.shortcal_timer = timestamp;
351 			common->ani.resetcal_timer = timestamp;
352 		}
353 	} else {
354 		if ((timestamp - common->ani.resetcal_timer) >=
355 		    ATH_RESTART_CALINTERVAL) {
356 			common->ani.caldone = ath9k_hw_reset_calvalid(ah);
357 			if (common->ani.caldone)
358 				common->ani.resetcal_timer = timestamp;
359 		}
360 	}
361 
362 	/* Verify whether we must check ANI */
363 	if ((timestamp - common->ani.checkani_timer) >= ah->config.ani_poll_interval) {
364 		aniflag = true;
365 		common->ani.checkani_timer = timestamp;
366 	}
367 
368 	/* Call ANI routine if necessary */
369 	if (aniflag) {
370 		spin_lock_irqsave(&common->cc_lock, flags);
371 		ath9k_hw_ani_monitor(ah, ah->curchan);
372 		ath_update_survey_stats(sc);
373 		spin_unlock_irqrestore(&common->cc_lock, flags);
374 	}
375 
376 	/* Perform calibration if necessary */
377 	if (longcal || shortcal) {
378 		int ret = ath9k_hw_calibrate(ah, ah->curchan, ah->rxchainmask,
379 					     longcal);
380 		if (ret < 0) {
381 			common->ani.caldone = 0;
382 			ath9k_queue_reset(sc, RESET_TYPE_CALIBRATION);
383 			return;
384 		}
385 
386 		common->ani.caldone = ret;
387 	}
388 
389 	ath_dbg(common, ANI,
390 		"Calibration @%lu finished: %s %s %s, caldone: %s\n",
391 		jiffies,
392 		longcal ? "long" : "", shortcal ? "short" : "",
393 		aniflag ? "ani" : "", common->ani.caldone ? "true" : "false");
394 
395 	ath9k_ps_restore(sc);
396 
397 set_timer:
398 	/*
399 	* Set timer interval based on previous results.
400 	* The interval must be the shortest necessary to satisfy ANI,
401 	* short calibration and long calibration.
402 	*/
403 	cal_interval = ATH_LONG_CALINTERVAL;
404 	cal_interval = min(cal_interval, (u32)ah->config.ani_poll_interval);
405 	if (!common->ani.caldone)
406 		cal_interval = min(cal_interval, (u32)short_cal_interval);
407 
408 	mod_timer(&common->ani.timer, jiffies + msecs_to_jiffies(cal_interval));
409 
410 	if (ar9003_is_paprd_enabled(ah) && ah->caldata) {
411 		if (!test_bit(PAPRD_DONE, &ah->caldata->cal_flags)) {
412 			ieee80211_queue_work(sc->hw, &sc->paprd_work);
413 		} else if (!ah->paprd_table_write_done) {
414 			ath9k_ps_wakeup(sc);
415 			ath_paprd_activate(sc);
416 			ath9k_ps_restore(sc);
417 		}
418 	}
419 }
420 
421 void ath_start_ani(struct ath_softc *sc)
422 {
423 	struct ath_hw *ah = sc->sc_ah;
424 	struct ath_common *common = ath9k_hw_common(ah);
425 	unsigned long timestamp = jiffies_to_msecs(jiffies);
426 
427 	if (common->disable_ani ||
428 	    !test_bit(ATH_OP_ANI_RUN, &common->op_flags) ||
429 	    sc->cur_chan->offchannel)
430 		return;
431 
432 	common->ani.longcal_timer = timestamp;
433 	common->ani.shortcal_timer = timestamp;
434 	common->ani.checkani_timer = timestamp;
435 
436 	ath_dbg(common, ANI, "Starting ANI\n");
437 	mod_timer(&common->ani.timer,
438 		  jiffies + msecs_to_jiffies((u32)ah->config.ani_poll_interval));
439 }
440 
441 void ath_stop_ani(struct ath_softc *sc)
442 {
443 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
444 
445 	ath_dbg(common, ANI, "Stopping ANI\n");
446 	del_timer_sync(&common->ani.timer);
447 }
448 
449 void ath_check_ani(struct ath_softc *sc)
450 {
451 	struct ath_hw *ah = sc->sc_ah;
452 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
453 	struct ath_beacon_config *cur_conf = &sc->cur_chan->beacon;
454 
455 	/*
456 	 * Check for the various conditions in which ANI has to
457 	 * be stopped.
458 	 */
459 	if (ah->opmode == NL80211_IFTYPE_ADHOC) {
460 		if (!cur_conf->enable_beacon)
461 			goto stop_ani;
462 	} else if (ah->opmode == NL80211_IFTYPE_AP) {
463 		if (!cur_conf->enable_beacon) {
464 			/*
465 			 * Disable ANI only when there are no
466 			 * associated stations.
467 			 */
468 			if (!test_bit(ATH_OP_PRIM_STA_VIF, &common->op_flags))
469 				goto stop_ani;
470 		}
471 	} else if (ah->opmode == NL80211_IFTYPE_STATION) {
472 		if (!test_bit(ATH_OP_PRIM_STA_VIF, &common->op_flags))
473 			goto stop_ani;
474 	}
475 
476 	if (!test_bit(ATH_OP_ANI_RUN, &common->op_flags)) {
477 		set_bit(ATH_OP_ANI_RUN, &common->op_flags);
478 		ath_start_ani(sc);
479 	}
480 
481 	return;
482 
483 stop_ani:
484 	clear_bit(ATH_OP_ANI_RUN, &common->op_flags);
485 	ath_stop_ani(sc);
486 }
487 
488 void ath_update_survey_nf(struct ath_softc *sc, int channel)
489 {
490 	struct ath_hw *ah = sc->sc_ah;
491 	struct ath9k_channel *chan = &ah->channels[channel];
492 	struct survey_info *survey = &sc->survey[channel];
493 
494 	if (chan->noisefloor) {
495 		survey->filled |= SURVEY_INFO_NOISE_DBM;
496 		survey->noise = ath9k_hw_getchan_noise(ah, chan,
497 						       chan->noisefloor);
498 	}
499 }
500 
501 /*
502  * Updates the survey statistics and returns the busy time since last
503  * update in %, if the measurement duration was long enough for the
504  * result to be useful, -1 otherwise.
505  */
506 int ath_update_survey_stats(struct ath_softc *sc)
507 {
508 	struct ath_hw *ah = sc->sc_ah;
509 	struct ath_common *common = ath9k_hw_common(ah);
510 	int pos = ah->curchan - &ah->channels[0];
511 	struct survey_info *survey = &sc->survey[pos];
512 	struct ath_cycle_counters *cc = &common->cc_survey;
513 	unsigned int div = common->clockrate * 1000;
514 	int ret = 0;
515 
516 	if (!ah->curchan)
517 		return -1;
518 
519 	if (ah->power_mode == ATH9K_PM_AWAKE)
520 		ath_hw_cycle_counters_update(common);
521 
522 	if (cc->cycles > 0) {
523 		survey->filled |= SURVEY_INFO_TIME |
524 			SURVEY_INFO_TIME_BUSY |
525 			SURVEY_INFO_TIME_RX |
526 			SURVEY_INFO_TIME_TX;
527 		survey->time += cc->cycles / div;
528 		survey->time_busy += cc->rx_busy / div;
529 		survey->time_rx += cc->rx_frame / div;
530 		survey->time_tx += cc->tx_frame / div;
531 	}
532 
533 	if (cc->cycles < div)
534 		return -1;
535 
536 	if (cc->cycles > 0)
537 		ret = cc->rx_busy * 100 / cc->cycles;
538 
539 	memset(cc, 0, sizeof(*cc));
540 
541 	ath_update_survey_nf(sc, pos);
542 
543 	return ret;
544 }
545