xref: /openbmc/linux/drivers/net/wireless/ath/ath9k/link.c (revision afc98d90)
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 	/*
119 	 * ensure that the PLL WAR is executed only
120 	 * after the STA is associated (or) if the
121 	 * beaconing had started in interfaces that
122 	 * uses beacons.
123 	 */
124 	if (!test_bit(SC_OP_BEACONS, &sc->sc_flags))
125 		return;
126 
127 	if (sc->tx99_state)
128 		return;
129 
130 	ath9k_ps_wakeup(sc);
131 	pll_sqsum = ar9003_get_pll_sqsum_dvc(sc->sc_ah);
132 	ath9k_ps_restore(sc);
133 	if (ath_hw_pll_rx_hang_check(sc, pll_sqsum))
134 		return;
135 
136 	ieee80211_queue_delayed_work(sc->hw, &sc->hw_pll_work,
137 				     msecs_to_jiffies(ATH_PLL_WORK_INTERVAL));
138 }
139 
140 /*
141  * PA Pre-distortion.
142  */
143 static void ath_paprd_activate(struct ath_softc *sc)
144 {
145 	struct ath_hw *ah = sc->sc_ah;
146 	struct ath_common *common = ath9k_hw_common(ah);
147 	struct ath9k_hw_cal_data *caldata = ah->caldata;
148 	int chain;
149 
150 	if (!caldata || !test_bit(PAPRD_DONE, &caldata->cal_flags)) {
151 		ath_dbg(common, CALIBRATE, "Failed to activate PAPRD\n");
152 		return;
153 	}
154 
155 	ar9003_paprd_enable(ah, false);
156 	for (chain = 0; chain < AR9300_MAX_CHAINS; chain++) {
157 		if (!(ah->txchainmask & BIT(chain)))
158 			continue;
159 
160 		ar9003_paprd_populate_single_table(ah, caldata, chain);
161 	}
162 
163 	ath_dbg(common, CALIBRATE, "Activating PAPRD\n");
164 	ar9003_paprd_enable(ah, true);
165 }
166 
167 static bool ath_paprd_send_frame(struct ath_softc *sc, struct sk_buff *skb, int chain)
168 {
169 	struct ieee80211_hw *hw = sc->hw;
170 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
171 	struct ath_hw *ah = sc->sc_ah;
172 	struct ath_common *common = ath9k_hw_common(ah);
173 	struct ath_tx_control txctl;
174 	int time_left;
175 
176 	memset(&txctl, 0, sizeof(txctl));
177 	txctl.txq = sc->tx.txq_map[IEEE80211_AC_BE];
178 
179 	memset(tx_info, 0, sizeof(*tx_info));
180 	tx_info->band = hw->conf.chandef.chan->band;
181 	tx_info->flags |= IEEE80211_TX_CTL_NO_ACK;
182 	tx_info->control.rates[0].idx = 0;
183 	tx_info->control.rates[0].count = 1;
184 	tx_info->control.rates[0].flags = IEEE80211_TX_RC_MCS;
185 	tx_info->control.rates[1].idx = -1;
186 
187 	init_completion(&sc->paprd_complete);
188 	txctl.paprd = BIT(chain);
189 
190 	if (ath_tx_start(hw, skb, &txctl) != 0) {
191 		ath_dbg(common, CALIBRATE, "PAPRD TX failed\n");
192 		dev_kfree_skb_any(skb);
193 		return false;
194 	}
195 
196 	time_left = wait_for_completion_timeout(&sc->paprd_complete,
197 			msecs_to_jiffies(ATH_PAPRD_TIMEOUT));
198 
199 	if (!time_left)
200 		ath_dbg(common, CALIBRATE,
201 			"Timeout waiting for paprd training on TX chain %d\n",
202 			chain);
203 
204 	return !!time_left;
205 }
206 
207 void ath_paprd_calibrate(struct work_struct *work)
208 {
209 	struct ath_softc *sc = container_of(work, struct ath_softc, paprd_work);
210 	struct ieee80211_hw *hw = sc->hw;
211 	struct ath_hw *ah = sc->sc_ah;
212 	struct ieee80211_hdr *hdr;
213 	struct sk_buff *skb = NULL;
214 	struct ath9k_hw_cal_data *caldata = ah->caldata;
215 	struct ath_common *common = ath9k_hw_common(ah);
216 	int ftype;
217 	int chain_ok = 0;
218 	int chain;
219 	int len = 1800;
220 	int ret;
221 
222 	if (!caldata ||
223 	    !test_bit(PAPRD_PACKET_SENT, &caldata->cal_flags) ||
224 	    test_bit(PAPRD_DONE, &caldata->cal_flags)) {
225 		ath_dbg(common, CALIBRATE, "Skipping PAPRD calibration\n");
226 		return;
227 	}
228 
229 	ath9k_ps_wakeup(sc);
230 
231 	if (ar9003_paprd_init_table(ah) < 0)
232 		goto fail_paprd;
233 
234 	skb = alloc_skb(len, GFP_KERNEL);
235 	if (!skb)
236 		goto fail_paprd;
237 
238 	skb_put(skb, len);
239 	memset(skb->data, 0, len);
240 	hdr = (struct ieee80211_hdr *)skb->data;
241 	ftype = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC;
242 	hdr->frame_control = cpu_to_le16(ftype);
243 	hdr->duration_id = cpu_to_le16(10);
244 	memcpy(hdr->addr1, hw->wiphy->perm_addr, ETH_ALEN);
245 	memcpy(hdr->addr2, hw->wiphy->perm_addr, ETH_ALEN);
246 	memcpy(hdr->addr3, hw->wiphy->perm_addr, ETH_ALEN);
247 
248 	for (chain = 0; chain < AR9300_MAX_CHAINS; chain++) {
249 		if (!(ah->txchainmask & BIT(chain)))
250 			continue;
251 
252 		chain_ok = 0;
253 		ar9003_paprd_setup_gain_table(ah, chain);
254 
255 		ath_dbg(common, CALIBRATE,
256 			"Sending PAPRD training frame on chain %d\n", chain);
257 		if (!ath_paprd_send_frame(sc, skb, chain))
258 			goto fail_paprd;
259 
260 		if (!ar9003_paprd_is_done(ah)) {
261 			ath_dbg(common, CALIBRATE,
262 				"PAPRD not yet done on chain %d\n", chain);
263 			break;
264 		}
265 
266 		ret = ar9003_paprd_create_curve(ah, caldata, chain);
267 		if (ret == -EINPROGRESS) {
268 			ath_dbg(common, CALIBRATE,
269 				"PAPRD curve on chain %d needs to be re-trained\n",
270 				chain);
271 			break;
272 		} else if (ret) {
273 			ath_dbg(common, CALIBRATE,
274 				"PAPRD create curve failed on chain %d\n",
275 				chain);
276 			break;
277 		}
278 
279 		chain_ok = 1;
280 	}
281 	kfree_skb(skb);
282 
283 	if (chain_ok) {
284 		set_bit(PAPRD_DONE, &caldata->cal_flags);
285 		ath_paprd_activate(sc);
286 	}
287 
288 fail_paprd:
289 	ath9k_ps_restore(sc);
290 }
291 
292 /*
293  *  ANI performs periodic noise floor calibration
294  *  that is used to adjust and optimize the chip performance.  This
295  *  takes environmental changes (location, temperature) into account.
296  *  When the task is complete, it reschedules itself depending on the
297  *  appropriate interval that was calculated.
298  */
299 void ath_ani_calibrate(unsigned long data)
300 {
301 	struct ath_softc *sc = (struct ath_softc *)data;
302 	struct ath_hw *ah = sc->sc_ah;
303 	struct ath_common *common = ath9k_hw_common(ah);
304 	bool longcal = false;
305 	bool shortcal = false;
306 	bool aniflag = false;
307 	unsigned int timestamp = jiffies_to_msecs(jiffies);
308 	u32 cal_interval, short_cal_interval, long_cal_interval;
309 	unsigned long flags;
310 
311 	if (ah->caldata && test_bit(NFCAL_INTF, &ah->caldata->cal_flags))
312 		long_cal_interval = ATH_LONG_CALINTERVAL_INT;
313 	else
314 		long_cal_interval = ATH_LONG_CALINTERVAL;
315 
316 	short_cal_interval = (ah->opmode == NL80211_IFTYPE_AP) ?
317 		ATH_AP_SHORT_CALINTERVAL : ATH_STA_SHORT_CALINTERVAL;
318 
319 	/* Only calibrate if awake */
320 	if (sc->sc_ah->power_mode != ATH9K_PM_AWAKE) {
321 		if (++ah->ani_skip_count >= ATH_ANI_MAX_SKIP_COUNT) {
322 			spin_lock_irqsave(&sc->sc_pm_lock, flags);
323 			sc->ps_flags |= PS_WAIT_FOR_ANI;
324 			spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
325 		}
326 		goto set_timer;
327 	}
328 	ah->ani_skip_count = 0;
329 	spin_lock_irqsave(&sc->sc_pm_lock, flags);
330 	sc->ps_flags &= ~PS_WAIT_FOR_ANI;
331 	spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
332 
333 	ath9k_ps_wakeup(sc);
334 
335 	/* Long calibration runs independently of short calibration. */
336 	if ((timestamp - common->ani.longcal_timer) >= long_cal_interval) {
337 		longcal = true;
338 		common->ani.longcal_timer = timestamp;
339 	}
340 
341 	/* Short calibration applies only while caldone is false */
342 	if (!common->ani.caldone) {
343 		if ((timestamp - common->ani.shortcal_timer) >= short_cal_interval) {
344 			shortcal = true;
345 			common->ani.shortcal_timer = timestamp;
346 			common->ani.resetcal_timer = timestamp;
347 		}
348 	} else {
349 		if ((timestamp - common->ani.resetcal_timer) >=
350 		    ATH_RESTART_CALINTERVAL) {
351 			common->ani.caldone = ath9k_hw_reset_calvalid(ah);
352 			if (common->ani.caldone)
353 				common->ani.resetcal_timer = timestamp;
354 		}
355 	}
356 
357 	/* Verify whether we must check ANI */
358 	if ((timestamp - common->ani.checkani_timer) >= ah->config.ani_poll_interval) {
359 		aniflag = true;
360 		common->ani.checkani_timer = timestamp;
361 	}
362 
363 	/* Call ANI routine if necessary */
364 	if (aniflag) {
365 		spin_lock(&common->cc_lock);
366 		ath9k_hw_ani_monitor(ah, ah->curchan);
367 		ath_update_survey_stats(sc);
368 		spin_unlock(&common->cc_lock);
369 	}
370 
371 	/* Perform calibration if necessary */
372 	if (longcal || shortcal) {
373 		common->ani.caldone =
374 			ath9k_hw_calibrate(ah, ah->curchan,
375 					   ah->rxchainmask, longcal);
376 	}
377 
378 	ath_dbg(common, ANI,
379 		"Calibration @%lu finished: %s %s %s, caldone: %s\n",
380 		jiffies,
381 		longcal ? "long" : "", shortcal ? "short" : "",
382 		aniflag ? "ani" : "", common->ani.caldone ? "true" : "false");
383 
384 	ath9k_ps_restore(sc);
385 
386 set_timer:
387 	/*
388 	* Set timer interval based on previous results.
389 	* The interval must be the shortest necessary to satisfy ANI,
390 	* short calibration and long calibration.
391 	*/
392 	cal_interval = ATH_LONG_CALINTERVAL;
393 	cal_interval = min(cal_interval, (u32)ah->config.ani_poll_interval);
394 	if (!common->ani.caldone)
395 		cal_interval = min(cal_interval, (u32)short_cal_interval);
396 
397 	mod_timer(&common->ani.timer, jiffies + msecs_to_jiffies(cal_interval));
398 
399 	if (ar9003_is_paprd_enabled(ah) && ah->caldata) {
400 		if (!test_bit(PAPRD_DONE, &ah->caldata->cal_flags)) {
401 			ieee80211_queue_work(sc->hw, &sc->paprd_work);
402 		} else if (!ah->paprd_table_write_done) {
403 			ath9k_ps_wakeup(sc);
404 			ath_paprd_activate(sc);
405 			ath9k_ps_restore(sc);
406 		}
407 	}
408 }
409 
410 void ath_start_ani(struct ath_softc *sc)
411 {
412 	struct ath_hw *ah = sc->sc_ah;
413 	struct ath_common *common = ath9k_hw_common(ah);
414 	unsigned long timestamp = jiffies_to_msecs(jiffies);
415 
416 	if (common->disable_ani ||
417 	    !test_bit(SC_OP_ANI_RUN, &sc->sc_flags) ||
418 	    (sc->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL))
419 		return;
420 
421 	common->ani.longcal_timer = timestamp;
422 	common->ani.shortcal_timer = timestamp;
423 	common->ani.checkani_timer = timestamp;
424 
425 	ath_dbg(common, ANI, "Starting ANI\n");
426 	mod_timer(&common->ani.timer,
427 		  jiffies + msecs_to_jiffies((u32)ah->config.ani_poll_interval));
428 }
429 
430 void ath_stop_ani(struct ath_softc *sc)
431 {
432 	struct ath_common *common = ath9k_hw_common(sc->sc_ah);
433 
434 	ath_dbg(common, ANI, "Stopping ANI\n");
435 	del_timer_sync(&common->ani.timer);
436 }
437 
438 void ath_check_ani(struct ath_softc *sc)
439 {
440 	struct ath_hw *ah = sc->sc_ah;
441 	struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
442 
443 	/*
444 	 * Check for the various conditions in which ANI has to
445 	 * be stopped.
446 	 */
447 	if (ah->opmode == NL80211_IFTYPE_ADHOC) {
448 		if (!cur_conf->enable_beacon)
449 			goto stop_ani;
450 	} else if (ah->opmode == NL80211_IFTYPE_AP) {
451 		if (!cur_conf->enable_beacon) {
452 			/*
453 			 * Disable ANI only when there are no
454 			 * associated stations.
455 			 */
456 			if (!test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags))
457 				goto stop_ani;
458 		}
459 	} else if (ah->opmode == NL80211_IFTYPE_STATION) {
460 		if (!test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags))
461 			goto stop_ani;
462 	}
463 
464 	if (!test_bit(SC_OP_ANI_RUN, &sc->sc_flags)) {
465 		set_bit(SC_OP_ANI_RUN, &sc->sc_flags);
466 		ath_start_ani(sc);
467 	}
468 
469 	return;
470 
471 stop_ani:
472 	clear_bit(SC_OP_ANI_RUN, &sc->sc_flags);
473 	ath_stop_ani(sc);
474 }
475 
476 void ath_update_survey_nf(struct ath_softc *sc, int channel)
477 {
478 	struct ath_hw *ah = sc->sc_ah;
479 	struct ath9k_channel *chan = &ah->channels[channel];
480 	struct survey_info *survey = &sc->survey[channel];
481 
482 	if (chan->noisefloor) {
483 		survey->filled |= SURVEY_INFO_NOISE_DBM;
484 		survey->noise = ath9k_hw_getchan_noise(ah, chan,
485 						       chan->noisefloor);
486 	}
487 }
488 
489 /*
490  * Updates the survey statistics and returns the busy time since last
491  * update in %, if the measurement duration was long enough for the
492  * result to be useful, -1 otherwise.
493  */
494 int ath_update_survey_stats(struct ath_softc *sc)
495 {
496 	struct ath_hw *ah = sc->sc_ah;
497 	struct ath_common *common = ath9k_hw_common(ah);
498 	int pos = ah->curchan - &ah->channels[0];
499 	struct survey_info *survey = &sc->survey[pos];
500 	struct ath_cycle_counters *cc = &common->cc_survey;
501 	unsigned int div = common->clockrate * 1000;
502 	int ret = 0;
503 
504 	if (!ah->curchan)
505 		return -1;
506 
507 	if (ah->power_mode == ATH9K_PM_AWAKE)
508 		ath_hw_cycle_counters_update(common);
509 
510 	if (cc->cycles > 0) {
511 		survey->filled |= SURVEY_INFO_CHANNEL_TIME |
512 			SURVEY_INFO_CHANNEL_TIME_BUSY |
513 			SURVEY_INFO_CHANNEL_TIME_RX |
514 			SURVEY_INFO_CHANNEL_TIME_TX;
515 		survey->channel_time += cc->cycles / div;
516 		survey->channel_time_busy += cc->rx_busy / div;
517 		survey->channel_time_rx += cc->rx_frame / div;
518 		survey->channel_time_tx += cc->tx_frame / div;
519 	}
520 
521 	if (cc->cycles < div)
522 		return -1;
523 
524 	if (cc->cycles > 0)
525 		ret = cc->rx_busy * 100 / cc->cycles;
526 
527 	memset(cc, 0, sizeof(*cc));
528 
529 	ath_update_survey_nf(sc, pos);
530 
531 	return ret;
532 }
533