Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wirel...
[sfrench/cifs-2.6.git] / drivers / net / wireless / ath / ath9k / link.c
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 ath9k_hw_cal_data *caldata = ah->caldata;
183         int chain;
184
185         if (!caldata || !caldata->paprd_done)
186                 return;
187
188         ath9k_ps_wakeup(sc);
189         ar9003_paprd_enable(ah, false);
190         for (chain = 0; chain < AR9300_MAX_CHAINS; chain++) {
191                 if (!(ah->txchainmask & BIT(chain)))
192                         continue;
193
194                 ar9003_paprd_populate_single_table(ah, caldata, chain);
195         }
196
197         ar9003_paprd_enable(ah, true);
198         ath9k_ps_restore(sc);
199 }
200
201 static bool ath_paprd_send_frame(struct ath_softc *sc, struct sk_buff *skb, int chain)
202 {
203         struct ieee80211_hw *hw = sc->hw;
204         struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
205         struct ath_hw *ah = sc->sc_ah;
206         struct ath_common *common = ath9k_hw_common(ah);
207         struct ath_tx_control txctl;
208         int time_left;
209
210         memset(&txctl, 0, sizeof(txctl));
211         txctl.txq = sc->tx.txq_map[IEEE80211_AC_BE];
212
213         memset(tx_info, 0, sizeof(*tx_info));
214         tx_info->band = hw->conf.channel->band;
215         tx_info->flags |= IEEE80211_TX_CTL_NO_ACK;
216         tx_info->control.rates[0].idx = 0;
217         tx_info->control.rates[0].count = 1;
218         tx_info->control.rates[0].flags = IEEE80211_TX_RC_MCS;
219         tx_info->control.rates[1].idx = -1;
220
221         init_completion(&sc->paprd_complete);
222         txctl.paprd = BIT(chain);
223
224         if (ath_tx_start(hw, skb, &txctl) != 0) {
225                 ath_dbg(common, CALIBRATE, "PAPRD TX failed\n");
226                 dev_kfree_skb_any(skb);
227                 return false;
228         }
229
230         time_left = wait_for_completion_timeout(&sc->paprd_complete,
231                         msecs_to_jiffies(ATH_PAPRD_TIMEOUT));
232
233         if (!time_left)
234                 ath_dbg(common, CALIBRATE,
235                         "Timeout waiting for paprd training on TX chain %d\n",
236                         chain);
237
238         return !!time_left;
239 }
240
241 void ath_paprd_calibrate(struct work_struct *work)
242 {
243         struct ath_softc *sc = container_of(work, struct ath_softc, paprd_work);
244         struct ieee80211_hw *hw = sc->hw;
245         struct ath_hw *ah = sc->sc_ah;
246         struct ieee80211_hdr *hdr;
247         struct sk_buff *skb = NULL;
248         struct ath9k_hw_cal_data *caldata = ah->caldata;
249         struct ath_common *common = ath9k_hw_common(ah);
250         int ftype;
251         int chain_ok = 0;
252         int chain;
253         int len = 1800;
254         int ret;
255
256         if (!caldata || !caldata->paprd_packet_sent || caldata->paprd_done)
257                 return;
258
259         ath9k_ps_wakeup(sc);
260
261         if (ar9003_paprd_init_table(ah) < 0)
262                 goto fail_paprd;
263
264         skb = alloc_skb(len, GFP_KERNEL);
265         if (!skb)
266                 goto fail_paprd;
267
268         skb_put(skb, len);
269         memset(skb->data, 0, len);
270         hdr = (struct ieee80211_hdr *)skb->data;
271         ftype = IEEE80211_FTYPE_DATA | IEEE80211_STYPE_NULLFUNC;
272         hdr->frame_control = cpu_to_le16(ftype);
273         hdr->duration_id = cpu_to_le16(10);
274         memcpy(hdr->addr1, hw->wiphy->perm_addr, ETH_ALEN);
275         memcpy(hdr->addr2, hw->wiphy->perm_addr, ETH_ALEN);
276         memcpy(hdr->addr3, hw->wiphy->perm_addr, ETH_ALEN);
277
278         for (chain = 0; chain < AR9300_MAX_CHAINS; chain++) {
279                 if (!(ah->txchainmask & BIT(chain)))
280                         continue;
281
282                 chain_ok = 0;
283                 ar9003_paprd_setup_gain_table(ah, chain);
284
285                 ath_dbg(common, CALIBRATE,
286                         "Sending PAPRD training frame on chain %d\n", chain);
287                 if (!ath_paprd_send_frame(sc, skb, chain))
288                         goto fail_paprd;
289
290                 if (!ar9003_paprd_is_done(ah)) {
291                         ath_dbg(common, CALIBRATE,
292                                 "PAPRD not yet done on chain %d\n", chain);
293                         break;
294                 }
295
296                 ret = ar9003_paprd_create_curve(ah, caldata, chain);
297                 if (ret == -EINPROGRESS) {
298                         ath_dbg(common, CALIBRATE,
299                                 "PAPRD curve on chain %d needs to be re-trained\n",
300                                 chain);
301                         break;
302                 } else if (ret) {
303                         ath_dbg(common, CALIBRATE,
304                                 "PAPRD create curve failed on chain %d\n",
305                                 chain);
306                         break;
307                 }
308
309                 chain_ok = 1;
310         }
311         kfree_skb(skb);
312
313         if (chain_ok) {
314                 caldata->paprd_done = true;
315                 ath_paprd_activate(sc);
316         }
317
318 fail_paprd:
319         ath9k_ps_restore(sc);
320 }
321
322 /*
323  *  ANI performs periodic noise floor calibration
324  *  that is used to adjust and optimize the chip performance.  This
325  *  takes environmental changes (location, temperature) into account.
326  *  When the task is complete, it reschedules itself depending on the
327  *  appropriate interval that was calculated.
328  */
329 void ath_ani_calibrate(unsigned long data)
330 {
331         struct ath_softc *sc = (struct ath_softc *)data;
332         struct ath_hw *ah = sc->sc_ah;
333         struct ath_common *common = ath9k_hw_common(ah);
334         bool longcal = false;
335         bool shortcal = false;
336         bool aniflag = false;
337         unsigned int timestamp = jiffies_to_msecs(jiffies);
338         u32 cal_interval, short_cal_interval, long_cal_interval;
339         unsigned long flags;
340
341         if (ah->caldata && ah->caldata->nfcal_interference)
342                 long_cal_interval = ATH_LONG_CALINTERVAL_INT;
343         else
344                 long_cal_interval = ATH_LONG_CALINTERVAL;
345
346         short_cal_interval = (ah->opmode == NL80211_IFTYPE_AP) ?
347                 ATH_AP_SHORT_CALINTERVAL : ATH_STA_SHORT_CALINTERVAL;
348
349         /* Only calibrate if awake */
350         if (sc->sc_ah->power_mode != ATH9K_PM_AWAKE) {
351                 if (++ah->ani_skip_count >= ATH_ANI_MAX_SKIP_COUNT) {
352                         spin_lock_irqsave(&sc->sc_pm_lock, flags);
353                         sc->ps_flags |= PS_WAIT_FOR_ANI;
354                         spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
355                 }
356                 goto set_timer;
357         }
358         ah->ani_skip_count = 0;
359         spin_lock_irqsave(&sc->sc_pm_lock, flags);
360         sc->ps_flags &= ~PS_WAIT_FOR_ANI;
361         spin_unlock_irqrestore(&sc->sc_pm_lock, flags);
362
363         ath9k_ps_wakeup(sc);
364
365         /* Long calibration runs independently of short calibration. */
366         if ((timestamp - common->ani.longcal_timer) >= long_cal_interval) {
367                 longcal = true;
368                 common->ani.longcal_timer = timestamp;
369         }
370
371         /* Short calibration applies only while caldone is false */
372         if (!common->ani.caldone) {
373                 if ((timestamp - common->ani.shortcal_timer) >= short_cal_interval) {
374                         shortcal = true;
375                         common->ani.shortcal_timer = timestamp;
376                         common->ani.resetcal_timer = timestamp;
377                 }
378         } else {
379                 if ((timestamp - common->ani.resetcal_timer) >=
380                     ATH_RESTART_CALINTERVAL) {
381                         common->ani.caldone = ath9k_hw_reset_calvalid(ah);
382                         if (common->ani.caldone)
383                                 common->ani.resetcal_timer = timestamp;
384                 }
385         }
386
387         /* Verify whether we must check ANI */
388         if (sc->sc_ah->config.enable_ani
389             && (timestamp - common->ani.checkani_timer) >=
390             ah->config.ani_poll_interval) {
391                 aniflag = true;
392                 common->ani.checkani_timer = timestamp;
393         }
394
395         /* Call ANI routine if necessary */
396         if (aniflag) {
397                 spin_lock_irqsave(&common->cc_lock, flags);
398                 ath9k_hw_ani_monitor(ah, ah->curchan);
399                 ath_update_survey_stats(sc);
400                 spin_unlock_irqrestore(&common->cc_lock, flags);
401         }
402
403         /* Perform calibration if necessary */
404         if (longcal || shortcal) {
405                 common->ani.caldone =
406                         ath9k_hw_calibrate(ah, ah->curchan,
407                                            ah->rxchainmask, longcal);
408         }
409
410         ath_dbg(common, ANI,
411                 "Calibration @%lu finished: %s %s %s, caldone: %s\n",
412                 jiffies,
413                 longcal ? "long" : "", shortcal ? "short" : "",
414                 aniflag ? "ani" : "", common->ani.caldone ? "true" : "false");
415
416         ath9k_debug_samp_bb_mac(sc);
417         ath9k_ps_restore(sc);
418
419 set_timer:
420         /*
421         * Set timer interval based on previous results.
422         * The interval must be the shortest necessary to satisfy ANI,
423         * short calibration and long calibration.
424         */
425         cal_interval = ATH_LONG_CALINTERVAL;
426         if (sc->sc_ah->config.enable_ani)
427                 cal_interval = min(cal_interval,
428                                    (u32)ah->config.ani_poll_interval);
429         if (!common->ani.caldone)
430                 cal_interval = min(cal_interval, (u32)short_cal_interval);
431
432         mod_timer(&common->ani.timer, jiffies + msecs_to_jiffies(cal_interval));
433         if (ah->eep_ops->get_eeprom(ah, EEP_PAPRD) && ah->caldata) {
434                 if (!ah->caldata->paprd_done)
435                         ieee80211_queue_work(sc->hw, &sc->paprd_work);
436                 else if (!ah->paprd_table_write_done)
437                         ath_paprd_activate(sc);
438         }
439 }
440
441 void ath_start_ani(struct ath_softc *sc)
442 {
443         struct ath_hw *ah = sc->sc_ah;
444         struct ath_common *common = ath9k_hw_common(ah);
445         unsigned long timestamp = jiffies_to_msecs(jiffies);
446
447         if (common->disable_ani ||
448             !test_bit(SC_OP_ANI_RUN, &sc->sc_flags) ||
449             (sc->hw->conf.flags & IEEE80211_CONF_OFFCHANNEL))
450                 return;
451
452         common->ani.longcal_timer = timestamp;
453         common->ani.shortcal_timer = timestamp;
454         common->ani.checkani_timer = timestamp;
455
456         ath_dbg(common, ANI, "Starting ANI\n");
457         mod_timer(&common->ani.timer,
458                   jiffies + msecs_to_jiffies((u32)ah->config.ani_poll_interval));
459 }
460
461 void ath_stop_ani(struct ath_softc *sc)
462 {
463         struct ath_common *common = ath9k_hw_common(sc->sc_ah);
464
465         ath_dbg(common, ANI, "Stopping ANI\n");
466         del_timer_sync(&common->ani.timer);
467 }
468
469 void ath_check_ani(struct ath_softc *sc)
470 {
471         struct ath_hw *ah = sc->sc_ah;
472         struct ath_beacon_config *cur_conf = &sc->cur_beacon_conf;
473
474         /*
475          * Check for the various conditions in which ANI has to
476          * be stopped.
477          */
478         if (ah->opmode == NL80211_IFTYPE_ADHOC) {
479                 if (!cur_conf->enable_beacon)
480                         goto stop_ani;
481         } else if (ah->opmode == NL80211_IFTYPE_AP) {
482                 if (!cur_conf->enable_beacon) {
483                         /*
484                          * Disable ANI only when there are no
485                          * associated stations.
486                          */
487                         if (!test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags))
488                                 goto stop_ani;
489                 }
490         } else if (ah->opmode == NL80211_IFTYPE_STATION) {
491                 if (!test_bit(SC_OP_PRIM_STA_VIF, &sc->sc_flags))
492                         goto stop_ani;
493         }
494
495         if (!test_bit(SC_OP_ANI_RUN, &sc->sc_flags)) {
496                 set_bit(SC_OP_ANI_RUN, &sc->sc_flags);
497                 ath_start_ani(sc);
498         }
499
500         return;
501
502 stop_ani:
503         clear_bit(SC_OP_ANI_RUN, &sc->sc_flags);
504         ath_stop_ani(sc);
505 }
506
507 void ath_update_survey_nf(struct ath_softc *sc, int channel)
508 {
509         struct ath_hw *ah = sc->sc_ah;
510         struct ath9k_channel *chan = &ah->channels[channel];
511         struct survey_info *survey = &sc->survey[channel];
512
513         if (chan->noisefloor) {
514                 survey->filled |= SURVEY_INFO_NOISE_DBM;
515                 survey->noise = ath9k_hw_getchan_noise(ah, chan);
516         }
517 }
518
519 /*
520  * Updates the survey statistics and returns the busy time since last
521  * update in %, if the measurement duration was long enough for the
522  * result to be useful, -1 otherwise.
523  */
524 int ath_update_survey_stats(struct ath_softc *sc)
525 {
526         struct ath_hw *ah = sc->sc_ah;
527         struct ath_common *common = ath9k_hw_common(ah);
528         int pos = ah->curchan - &ah->channels[0];
529         struct survey_info *survey = &sc->survey[pos];
530         struct ath_cycle_counters *cc = &common->cc_survey;
531         unsigned int div = common->clockrate * 1000;
532         int ret = 0;
533
534         if (!ah->curchan)
535                 return -1;
536
537         if (ah->power_mode == ATH9K_PM_AWAKE)
538                 ath_hw_cycle_counters_update(common);
539
540         if (cc->cycles > 0) {
541                 survey->filled |= SURVEY_INFO_CHANNEL_TIME |
542                         SURVEY_INFO_CHANNEL_TIME_BUSY |
543                         SURVEY_INFO_CHANNEL_TIME_RX |
544                         SURVEY_INFO_CHANNEL_TIME_TX;
545                 survey->channel_time += cc->cycles / div;
546                 survey->channel_time_busy += cc->rx_busy / div;
547                 survey->channel_time_rx += cc->rx_frame / div;
548                 survey->channel_time_tx += cc->tx_frame / div;
549         }
550
551         if (cc->cycles < div)
552                 return -1;
553
554         if (cc->cycles > 0)
555                 ret = cc->rx_busy * 100 / cc->cycles;
556
557         memset(cc, 0, sizeof(*cc));
558
559         ath_update_survey_nf(sc, pos);
560
561         return ret;
562 }