xref: /openbmc/linux/drivers/net/wireless/ath/ath9k/link.c (revision 275876e2)
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 
32 	if (sc->tx99_state) {
33 		ath_dbg(ath9k_hw_common(sc->sc_ah), RESET,
34 			"skip tx hung detection on tx99\n");
35 		return;
36 	}
37 
38 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
39 		txq = sc->tx.txq_map[i];
40 
41 		ath_txq_lock(sc, txq);
42 		if (txq->axq_depth) {
43 			if (txq->axq_tx_inprogress) {
44 				needreset = true;
45 				ath_txq_unlock(sc, txq);
46 				break;
47 			} else {
48 				txq->axq_tx_inprogress = true;
49 			}
50 		}
51 		ath_txq_unlock(sc, txq);
52 	}
53 
54 	if (needreset) {
55 		ath_dbg(ath9k_hw_common(sc->sc_ah), RESET,
56 			"tx hung, resetting the chip\n");
57 		ath9k_queue_reset(sc, RESET_TYPE_TX_HANG);
58 		return;
59 	}
60 
61 	ieee80211_queue_delayed_work(sc->hw, &sc->tx_complete_work,
62 				     msecs_to_jiffies(ATH_TX_COMPLETE_POLL_INT));
63 }
64 
65 /*
66  * Checks if the BB/MAC is hung.
67  */
68 bool ath_hw_check(struct ath_softc *sc)
69 {
70 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
71 	enum ath_reset_type type;
72 	bool is_alive;
73 
74 	ath9k_ps_wakeup(sc);
75 
76 	is_alive = ath9k_hw_check_alive(sc->sc_ah);
77 
78 	if (!is_alive) {
79 		ath_dbg(common, RESET,
80 			"HW hang detected, schedule chip reset\n");
81 		type = RESET_TYPE_MAC_HANG;
82 		ath9k_queue_reset(sc, type);
83 	}
84 
85 	ath9k_ps_restore(sc);
86 
87 	return is_alive;
88 }
89 
90 /*
91  * PLL-WAR for AR9485/AR9340
92  */
93 static bool ath_hw_pll_rx_hang_check(struct ath_softc *sc, u32 pll_sqsum)
94 {
95 	static int count;
96 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
97 
98 	if (pll_sqsum >= 0x40000) {
99 		count++;
100 		if (count == 3) {
101 			ath_dbg(common, RESET, "PLL WAR, resetting the chip\n");
102 			ath9k_queue_reset(sc, RESET_TYPE_PLL_HANG);
103 			count = 0;
104 			return true;
105 		}
106 	} else {
107 		count = 0;
108 	}
109 
110 	return false;
111 }
112 
113 void ath_hw_pll_work(struct work_struct *work)
114 {
115 	u32 pll_sqsum;
116 	struct ath_softc *sc = container_of(work, struct ath_softc,
117 					    hw_pll_work.work);
118 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
119 	/*
120 	 * ensure that the PLL WAR is executed only
121 	 * after the STA is associated (or) if the
122 	 * beaconing had started in interfaces that
123 	 * uses beacons.
124 	 */
125 	if (!test_bit(ATH_OP_BEACONS, &common->op_flags))
126 		return;
127 
128 	if (sc->tx99_state)
129 		return;
130 
131 	ath9k_ps_wakeup(sc);
132 	pll_sqsum = ar9003_get_pll_sqsum_dvc(sc->sc_ah);
133 	ath9k_ps_restore(sc);
134 	if (ath_hw_pll_rx_hang_check(sc, pll_sqsum))
135 		return;
136 
137 	ieee80211_queue_delayed_work(sc->hw, &sc->hw_pll_work,
138 				     msecs_to_jiffies(ATH_PLL_WORK_INTERVAL));
139 }
140 
141 /*
142  * PA Pre-distortion.
143  */
144 static void ath_paprd_activate(struct ath_softc *sc)
145 {
146 	struct ath_hw *ah = sc->sc_ah;
147 	struct ath_common *common = ath9k_hw_common(ah);
148 	struct ath9k_hw_cal_data *caldata = ah->caldata;
149 	int chain;
150 
151 	if (!caldata || !test_bit(PAPRD_DONE, &caldata->cal_flags)) {
152 		ath_dbg(common, CALIBRATE, "Failed to activate PAPRD\n");
153 		return;
154 	}
155 
156 	ar9003_paprd_enable(ah, false);
157 	for (chain = 0; chain < AR9300_MAX_CHAINS; chain++) {
158 		if (!(ah->txchainmask & BIT(chain)))
159 			continue;
160 
161 		ar9003_paprd_populate_single_table(ah, caldata, chain);
162 	}
163 
164 	ath_dbg(common, CALIBRATE, "Activating PAPRD\n");
165 	ar9003_paprd_enable(ah, true);
166 }
167 
168 static bool ath_paprd_send_frame(struct ath_softc *sc, struct sk_buff *skb, int chain)
169 {
170 	struct ieee80211_hw *hw = sc->hw;
171 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
172 	struct ath_hw *ah = sc->sc_ah;
173 	struct ath_common *common = ath9k_hw_common(ah);
174 	struct ath_tx_control txctl;
175 	int time_left;
176 
177 	memset(&txctl, 0, sizeof(txctl));
178 	txctl.txq = sc->tx.txq_map[IEEE80211_AC_BE];
179 
180 	memset(tx_info, 0, sizeof(*tx_info));
181 	tx_info->band = sc->cur_chandef.chan->band;
182 	tx_info->flags |= IEEE80211_TX_CTL_NO_ACK;
183 	tx_info->control.rates[0].idx = 0;
184 	tx_info->control.rates[0].count = 1;
185 	tx_info->control.rates[0].flags = IEEE80211_TX_RC_MCS;
186 	tx_info->control.rates[1].idx = -1;
187 
188 	init_completion(&sc->paprd_complete);
189 	txctl.paprd = BIT(chain);
190 
191 	if (ath_tx_start(hw, skb, &txctl) != 0) {
192 		ath_dbg(common, CALIBRATE, "PAPRD TX failed\n");
193 		dev_kfree_skb_any(skb);
194 		return false;
195 	}
196 
197 	time_left = wait_for_completion_timeout(&sc->paprd_complete,
198 			msecs_to_jiffies(ATH_PAPRD_TIMEOUT));
199 
200 	if (!time_left)
201 		ath_dbg(common, CALIBRATE,
202 			"Timeout waiting for paprd training on TX chain %d\n",
203 			chain);
204 
205 	return !!time_left;
206 }
207 
208 void ath_paprd_calibrate(struct work_struct *work)
209 {
210 	struct ath_softc *sc = container_of(work, struct ath_softc, paprd_work);
211 	struct ieee80211_hw *hw = sc->hw;
212 	struct ath_hw *ah = sc->sc_ah;
213 	struct ieee80211_hdr *hdr;
214 	struct sk_buff *skb = NULL;
215 	struct ath9k_hw_cal_data *caldata = ah->caldata;
216 	struct ath_common *common = ath9k_hw_common(ah);
217 	int ftype;
218 	int chain_ok = 0;
219 	int chain;
220 	int len = 1800;
221 	int ret;
222 
223 	if (!caldata ||
224 	    !test_bit(PAPRD_PACKET_SENT, &caldata->cal_flags) ||
225 	    test_bit(PAPRD_DONE, &caldata->cal_flags)) {
226 		ath_dbg(common, CALIBRATE, "Skipping PAPRD calibration\n");
227 		return;
228 	}
229 
230 	ath9k_ps_wakeup(sc);
231 
232 	if (ar9003_paprd_init_table(ah) < 0)
233 		goto fail_paprd;
234 
235 	skb = alloc_skb(len, GFP_KERNEL);
236 	if (!skb)
237 		goto fail_paprd;
238 
239 	skb_put(skb, len);
240 	memset(skb->data, 0, len);
241 	hdr = (struct ieee80211_hdr *)skb->data;
242 	ftype = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC;
243 	hdr->frame_control = cpu_to_le16(ftype);
244 	hdr->duration_id = cpu_to_le16(10);
245 	memcpy(hdr->addr1, hw->wiphy->perm_addr, ETH_ALEN);
246 	memcpy(hdr->addr2, hw->wiphy->perm_addr, ETH_ALEN);
247 	memcpy(hdr->addr3, hw->wiphy->perm_addr, ETH_ALEN);
248 
249 	for (chain = 0; chain < AR9300_MAX_CHAINS; chain++) {
250 		if (!(ah->txchainmask & BIT(chain)))
251 			continue;
252 
253 		chain_ok = 0;
254 		ar9003_paprd_setup_gain_table(ah, chain);
255 
256 		ath_dbg(common, CALIBRATE,
257 			"Sending PAPRD training frame on chain %d\n", chain);
258 		if (!ath_paprd_send_frame(sc, skb, chain))
259 			goto fail_paprd;
260 
261 		if (!ar9003_paprd_is_done(ah)) {
262 			ath_dbg(common, CALIBRATE,
263 				"PAPRD not yet done on chain %d\n", chain);
264 			break;
265 		}
266 
267 		ret = ar9003_paprd_create_curve(ah, caldata, chain);
268 		if (ret == -EINPROGRESS) {
269 			ath_dbg(common, CALIBRATE,
270 				"PAPRD curve on chain %d needs to be re-trained\n",
271 				chain);
272 			break;
273 		} else if (ret) {
274 			ath_dbg(common, CALIBRATE,
275 				"PAPRD create curve failed on chain %d\n",
276 				chain);
277 			break;
278 		}
279 
280 		chain_ok = 1;
281 	}
282 	kfree_skb(skb);
283 
284 	if (chain_ok) {
285 		set_bit(PAPRD_DONE, &caldata->cal_flags);
286 		ath_paprd_activate(sc);
287 	}
288 
289 fail_paprd:
290 	ath9k_ps_restore(sc);
291 }
292 
293 /*
294  *  ANI performs periodic noise floor calibration
295  *  that is used to adjust and optimize the chip performance.  This
296  *  takes environmental changes (location, temperature) into account.
297  *  When the task is complete, it reschedules itself depending on the
298  *  appropriate interval that was calculated.
299  */
300 void ath_ani_calibrate(unsigned long data)
301 {
302 	struct ath_softc *sc = (struct ath_softc *)data;
303 	struct ath_hw *ah = sc->sc_ah;
304 	struct ath_common *common = ath9k_hw_common(ah);
305 	bool longcal = false;
306 	bool shortcal = false;
307 	bool aniflag = false;
308 	unsigned int timestamp = jiffies_to_msecs(jiffies);
309 	u32 cal_interval, short_cal_interval, long_cal_interval;
310 	unsigned long flags;
311 
312 	if (ah->caldata && test_bit(NFCAL_INTF, &ah->caldata->cal_flags))
313 		long_cal_interval = ATH_LONG_CALINTERVAL_INT;
314 	else
315 		long_cal_interval = ATH_LONG_CALINTERVAL;
316 
317 	short_cal_interval = (ah->opmode == NL80211_IFTYPE_AP) ?
318 		ATH_AP_SHORT_CALINTERVAL : ATH_STA_SHORT_CALINTERVAL;
319 
320 	/* Only calibrate if awake */
321 	if (sc->sc_ah->power_mode != ATH9K_PM_AWAKE) {
322 		if (++ah->ani_skip_count >= ATH_ANI_MAX_SKIP_COUNT) {
323 			spin_lock_irqsave(&sc->sc_pm_lock, flags);
324 			sc->ps_flags |= PS_WAIT_FOR_ANI;
325 			spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
326 		}
327 		goto set_timer;
328 	}
329 	ah->ani_skip_count = 0;
330 	spin_lock_irqsave(&sc->sc_pm_lock, flags);
331 	sc->ps_flags &= ~PS_WAIT_FOR_ANI;
332 	spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
333 
334 	ath9k_ps_wakeup(sc);
335 
336 	/* Long calibration runs independently of short calibration. */
337 	if ((timestamp - common->ani.longcal_timer) >= long_cal_interval) {
338 		longcal = true;
339 		common->ani.longcal_timer = timestamp;
340 	}
341 
342 	/* Short calibration applies only while caldone is false */
343 	if (!common->ani.caldone) {
344 		if ((timestamp - common->ani.shortcal_timer) >= short_cal_interval) {
345 			shortcal = true;
346 			common->ani.shortcal_timer = timestamp;
347 			common->ani.resetcal_timer = timestamp;
348 		}
349 	} else {
350 		if ((timestamp - common->ani.resetcal_timer) >=
351 		    ATH_RESTART_CALINTERVAL) {
352 			common->ani.caldone = ath9k_hw_reset_calvalid(ah);
353 			if (common->ani.caldone)
354 				common->ani.resetcal_timer = timestamp;
355 		}
356 	}
357 
358 	/* Verify whether we must check ANI */
359 	if ((timestamp - common->ani.checkani_timer) >= ah->config.ani_poll_interval) {
360 		aniflag = true;
361 		common->ani.checkani_timer = timestamp;
362 	}
363 
364 	/* Call ANI routine if necessary */
365 	if (aniflag) {
366 		spin_lock(&common->cc_lock);
367 		ath9k_hw_ani_monitor(ah, ah->curchan);
368 		ath_update_survey_stats(sc);
369 		spin_unlock(&common->cc_lock);
370 	}
371 
372 	/* Perform calibration if necessary */
373 	if (longcal || shortcal) {
374 		common->ani.caldone =
375 			ath9k_hw_calibrate(ah, ah->curchan,
376 					   ah->rxchainmask, longcal);
377 	}
378 
379 	ath_dbg(common, ANI,
380 		"Calibration @%lu finished: %s %s %s, caldone: %s\n",
381 		jiffies,
382 		longcal ? "long" : "", shortcal ? "short" : "",
383 		aniflag ? "ani" : "", common->ani.caldone ? "true" : "false");
384 
385 	ath9k_ps_restore(sc);
386 
387 set_timer:
388 	/*
389 	* Set timer interval based on previous results.
390 	* The interval must be the shortest necessary to satisfy ANI,
391 	* short calibration and long calibration.
392 	*/
393 	cal_interval = ATH_LONG_CALINTERVAL;
394 	cal_interval = min(cal_interval, (u32)ah->config.ani_poll_interval);
395 	if (!common->ani.caldone)
396 		cal_interval = min(cal_interval, (u32)short_cal_interval);
397 
398 	mod_timer(&common->ani.timer, jiffies + msecs_to_jiffies(cal_interval));
399 
400 	if (ar9003_is_paprd_enabled(ah) && ah->caldata) {
401 		if (!test_bit(PAPRD_DONE, &ah->caldata->cal_flags)) {
402 			ieee80211_queue_work(sc->hw, &sc->paprd_work);
403 		} else if (!ah->paprd_table_write_done) {
404 			ath9k_ps_wakeup(sc);
405 			ath_paprd_activate(sc);
406 			ath9k_ps_restore(sc);
407 		}
408 	}
409 }
410 
411 void ath_start_ani(struct ath_softc *sc)
412 {
413 	struct ath_hw *ah = sc->sc_ah;
414 	struct ath_common *common = ath9k_hw_common(ah);
415 	unsigned long timestamp = jiffies_to_msecs(jiffies);
416 
417 	if (common->disable_ani ||
418 	    !test_bit(ATH_OP_ANI_RUN, &common->op_flags) ||
419 	    sc->cur_chan->offchannel)
420 		return;
421 
422 	common->ani.longcal_timer = timestamp;
423 	common->ani.shortcal_timer = timestamp;
424 	common->ani.checkani_timer = timestamp;
425 
426 	ath_dbg(common, ANI, "Starting ANI\n");
427 	mod_timer(&common->ani.timer,
428 		  jiffies + msecs_to_jiffies((u32)ah->config.ani_poll_interval));
429 }
430 
431 void ath_stop_ani(struct ath_softc *sc)
432 {
433 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
434 
435 	ath_dbg(common, ANI, "Stopping ANI\n");
436 	del_timer_sync(&common->ani.timer);
437 }
438 
439 void ath_check_ani(struct ath_softc *sc)
440 {
441 	struct ath_hw *ah = sc->sc_ah;
442 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
443 	struct ath_beacon_config *cur_conf = &sc->cur_chan->beacon;
444 
445 	/*
446 	 * Check for the various conditions in which ANI has to
447 	 * be stopped.
448 	 */
449 	if (ah->opmode == NL80211_IFTYPE_ADHOC) {
450 		if (!cur_conf->enable_beacon)
451 			goto stop_ani;
452 	} else if (ah->opmode == NL80211_IFTYPE_AP) {
453 		if (!cur_conf->enable_beacon) {
454 			/*
455 			 * Disable ANI only when there are no
456 			 * associated stations.
457 			 */
458 			if (!test_bit(ATH_OP_PRIM_STA_VIF, &common->op_flags))
459 				goto stop_ani;
460 		}
461 	} else if (ah->opmode == NL80211_IFTYPE_STATION) {
462 		if (!test_bit(ATH_OP_PRIM_STA_VIF, &common->op_flags))
463 			goto stop_ani;
464 	}
465 
466 	if (!test_bit(ATH_OP_ANI_RUN, &common->op_flags)) {
467 		set_bit(ATH_OP_ANI_RUN, &common->op_flags);
468 		ath_start_ani(sc);
469 	}
470 
471 	return;
472 
473 stop_ani:
474 	clear_bit(ATH_OP_ANI_RUN, &common->op_flags);
475 	ath_stop_ani(sc);
476 }
477 
478 void ath_update_survey_nf(struct ath_softc *sc, int channel)
479 {
480 	struct ath_hw *ah = sc->sc_ah;
481 	struct ath9k_channel *chan = &ah->channels[channel];
482 	struct survey_info *survey = &sc->survey[channel];
483 
484 	if (chan->noisefloor) {
485 		survey->filled |= SURVEY_INFO_NOISE_DBM;
486 		survey->noise = ath9k_hw_getchan_noise(ah, chan,
487 						       chan->noisefloor);
488 	}
489 }
490 
491 /*
492  * Updates the survey statistics and returns the busy time since last
493  * update in %, if the measurement duration was long enough for the
494  * result to be useful, -1 otherwise.
495  */
496 int ath_update_survey_stats(struct ath_softc *sc)
497 {
498 	struct ath_hw *ah = sc->sc_ah;
499 	struct ath_common *common = ath9k_hw_common(ah);
500 	int pos = ah->curchan - &ah->channels[0];
501 	struct survey_info *survey = &sc->survey[pos];
502 	struct ath_cycle_counters *cc = &common->cc_survey;
503 	unsigned int div = common->clockrate * 1000;
504 	int ret = 0;
505 
506 	if (!ah->curchan)
507 		return -1;
508 
509 	if (ah->power_mode == ATH9K_PM_AWAKE)
510 		ath_hw_cycle_counters_update(common);
511 
512 	if (cc->cycles > 0) {
513 		survey->filled |= SURVEY_INFO_CHANNEL_TIME |
514 			SURVEY_INFO_CHANNEL_TIME_BUSY |
515 			SURVEY_INFO_CHANNEL_TIME_RX |
516 			SURVEY_INFO_CHANNEL_TIME_TX;
517 		survey->channel_time += cc->cycles / div;
518 		survey->channel_time_busy += cc->rx_busy / div;
519 		survey->channel_time_rx += cc->rx_frame / div;
520 		survey->channel_time_tx += cc->tx_frame / div;
521 	}
522 
523 	if (cc->cycles < div)
524 		return -1;
525 
526 	if (cc->cycles > 0)
527 		ret = cc->rx_busy * 100 / cc->cycles;
528 
529 	memset(cc, 0, sizeof(*cc));
530 
531 	ath_update_survey_nf(sc, pos);
532 
533 	return ret;
534 }
535