1 /*
2 * Copyright (c) 2008-2011 Atheros Communications 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 "hw.h"
18 #include "hw-ops.h"
19 #include <linux/export.h>
20
21 /* Common calibration code */
22
23
ath9k_hw_get_nf_hist_mid(int16_t * nfCalBuffer)24 static int16_t ath9k_hw_get_nf_hist_mid(int16_t *nfCalBuffer)
25 {
26 int16_t nfval;
27 int16_t sort[ATH9K_NF_CAL_HIST_MAX];
28 int i, j;
29
30 for (i = 0; i < ATH9K_NF_CAL_HIST_MAX; i++)
31 sort[i] = nfCalBuffer[i];
32
33 for (i = 0; i < ATH9K_NF_CAL_HIST_MAX - 1; i++) {
34 for (j = 1; j < ATH9K_NF_CAL_HIST_MAX - i; j++) {
35 if (sort[j] > sort[j - 1])
36 swap(sort[j], sort[j - 1]);
37 }
38 }
39 nfval = sort[(ATH9K_NF_CAL_HIST_MAX - 1) >> 1];
40
41 return nfval;
42 }
43
ath9k_hw_get_nf_limits(struct ath_hw * ah,struct ath9k_channel * chan)44 static struct ath_nf_limits *ath9k_hw_get_nf_limits(struct ath_hw *ah,
45 struct ath9k_channel *chan)
46 {
47 struct ath_nf_limits *limit;
48
49 if (!chan || IS_CHAN_2GHZ(chan))
50 limit = &ah->nf_2g;
51 else
52 limit = &ah->nf_5g;
53
54 return limit;
55 }
56
ath9k_hw_get_default_nf(struct ath_hw * ah,struct ath9k_channel * chan,int chain)57 static s16 ath9k_hw_get_default_nf(struct ath_hw *ah,
58 struct ath9k_channel *chan,
59 int chain)
60 {
61 s16 calib_nf = ath9k_hw_get_nf_limits(ah, chan)->cal[chain];
62
63 if (calib_nf)
64 return calib_nf;
65 else
66 return ath9k_hw_get_nf_limits(ah, chan)->nominal;
67 }
68
ath9k_hw_getchan_noise(struct ath_hw * ah,struct ath9k_channel * chan,s16 nf)69 s16 ath9k_hw_getchan_noise(struct ath_hw *ah, struct ath9k_channel *chan,
70 s16 nf)
71 {
72 s8 noise = ATH_DEFAULT_NOISE_FLOOR;
73
74 if (nf) {
75 s8 delta = nf - ATH9K_NF_CAL_NOISE_THRESH -
76 ath9k_hw_get_default_nf(ah, chan, 0);
77 if (delta > 0)
78 noise += delta;
79 }
80 return noise;
81 }
82 EXPORT_SYMBOL(ath9k_hw_getchan_noise);
83
ath9k_hw_update_nfcal_hist_buffer(struct ath_hw * ah,struct ath9k_hw_cal_data * cal,int16_t * nfarray)84 static void ath9k_hw_update_nfcal_hist_buffer(struct ath_hw *ah,
85 struct ath9k_hw_cal_data *cal,
86 int16_t *nfarray)
87 {
88 struct ath_common *common = ath9k_hw_common(ah);
89 struct ath_nf_limits *limit;
90 struct ath9k_nfcal_hist *h;
91 bool high_nf_mid = false;
92 u8 chainmask = (ah->rxchainmask << 3) | ah->rxchainmask;
93 int i;
94
95 h = cal->nfCalHist;
96 limit = ath9k_hw_get_nf_limits(ah, ah->curchan);
97
98 for (i = 0; i < NUM_NF_READINGS; i++) {
99 if (!(chainmask & (1 << i)) ||
100 ((i >= AR5416_MAX_CHAINS) && !IS_CHAN_HT40(ah->curchan)))
101 continue;
102
103 h[i].nfCalBuffer[h[i].currIndex] = nfarray[i];
104
105 if (++h[i].currIndex >= ATH9K_NF_CAL_HIST_MAX)
106 h[i].currIndex = 0;
107
108 if (h[i].invalidNFcount > 0) {
109 h[i].invalidNFcount--;
110 h[i].privNF = nfarray[i];
111 } else {
112 h[i].privNF =
113 ath9k_hw_get_nf_hist_mid(h[i].nfCalBuffer);
114 }
115
116 if (!h[i].privNF)
117 continue;
118
119 if (h[i].privNF > limit->max) {
120 high_nf_mid = true;
121
122 ath_dbg(common, CALIBRATE,
123 "NFmid[%d] (%d) > MAX (%d), %s\n",
124 i, h[i].privNF, limit->max,
125 (test_bit(NFCAL_INTF, &cal->cal_flags) ?
126 "not corrected (due to interference)" :
127 "correcting to MAX"));
128
129 /*
130 * Normally we limit the average noise floor by the
131 * hardware specific maximum here. However if we have
132 * encountered stuck beacons because of interference,
133 * we bypass this limit here in order to better deal
134 * with our environment.
135 */
136 if (!test_bit(NFCAL_INTF, &cal->cal_flags))
137 h[i].privNF = limit->max;
138 }
139 }
140
141 /*
142 * If the noise floor seems normal for all chains, assume that
143 * there is no significant interference in the environment anymore.
144 * Re-enable the enforcement of the NF maximum again.
145 */
146 if (!high_nf_mid)
147 clear_bit(NFCAL_INTF, &cal->cal_flags);
148 }
149
ath9k_hw_get_nf_thresh(struct ath_hw * ah,enum nl80211_band band,int16_t * nft)150 static bool ath9k_hw_get_nf_thresh(struct ath_hw *ah,
151 enum nl80211_band band,
152 int16_t *nft)
153 {
154 switch (band) {
155 case NL80211_BAND_5GHZ:
156 *nft = (int8_t)ah->eep_ops->get_eeprom(ah, EEP_NFTHRESH_5);
157 break;
158 case NL80211_BAND_2GHZ:
159 *nft = (int8_t)ah->eep_ops->get_eeprom(ah, EEP_NFTHRESH_2);
160 break;
161 default:
162 BUG_ON(1);
163 return false;
164 }
165
166 return true;
167 }
168
ath9k_hw_reset_calibration(struct ath_hw * ah,struct ath9k_cal_list * currCal)169 void ath9k_hw_reset_calibration(struct ath_hw *ah,
170 struct ath9k_cal_list *currCal)
171 {
172 int i;
173
174 ath9k_hw_setup_calibration(ah, currCal);
175
176 ah->cal_start_time = jiffies;
177 currCal->calState = CAL_RUNNING;
178
179 for (i = 0; i < AR5416_MAX_CHAINS; i++) {
180 ah->meas0.sign[i] = 0;
181 ah->meas1.sign[i] = 0;
182 ah->meas2.sign[i] = 0;
183 ah->meas3.sign[i] = 0;
184 }
185
186 ah->cal_samples = 0;
187 }
188
189 /* This is done for the currently configured channel */
ath9k_hw_reset_calvalid(struct ath_hw * ah)190 bool ath9k_hw_reset_calvalid(struct ath_hw *ah)
191 {
192 struct ath_common *common = ath9k_hw_common(ah);
193 struct ath9k_cal_list *currCal = ah->cal_list_curr;
194
195 if (!ah->caldata)
196 return true;
197
198 if (!AR_SREV_9100(ah) && !AR_SREV_9160_10_OR_LATER(ah))
199 return true;
200
201 if (currCal == NULL)
202 return true;
203
204 if (currCal->calState != CAL_DONE) {
205 ath_dbg(common, CALIBRATE, "Calibration state incorrect, %d\n",
206 currCal->calState);
207 return true;
208 }
209
210 currCal = ah->cal_list;
211 do {
212 ath_dbg(common, CALIBRATE, "Resetting Cal %d state for channel %u\n",
213 currCal->calData->calType,
214 ah->curchan->chan->center_freq);
215
216 ah->caldata->CalValid &= ~currCal->calData->calType;
217 currCal->calState = CAL_WAITING;
218
219 currCal = currCal->calNext;
220 } while (currCal != ah->cal_list);
221
222 return false;
223 }
224 EXPORT_SYMBOL(ath9k_hw_reset_calvalid);
225
ath9k_hw_start_nfcal(struct ath_hw * ah,bool update)226 void ath9k_hw_start_nfcal(struct ath_hw *ah, bool update)
227 {
228 if (ah->caldata)
229 set_bit(NFCAL_PENDING, &ah->caldata->cal_flags);
230
231 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah),
232 AR_PHY_AGC_CONTROL_ENABLE_NF);
233
234 if (update)
235 REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL(ah),
236 AR_PHY_AGC_CONTROL_NO_UPDATE_NF);
237 else
238 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah),
239 AR_PHY_AGC_CONTROL_NO_UPDATE_NF);
240
241 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah), AR_PHY_AGC_CONTROL_NF);
242 }
243
ath9k_hw_loadnf(struct ath_hw * ah,struct ath9k_channel * chan)244 int ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan)
245 {
246 struct ath9k_nfcal_hist *h = NULL;
247 unsigned i, j;
248 u8 chainmask = (ah->rxchainmask << 3) | ah->rxchainmask;
249 struct ath_common *common = ath9k_hw_common(ah);
250 s16 default_nf = ath9k_hw_get_nf_limits(ah, chan)->nominal;
251 u32 bb_agc_ctl = REG_READ(ah, AR_PHY_AGC_CONTROL(ah));
252
253 if (ah->caldata)
254 h = ah->caldata->nfCalHist;
255
256 ENABLE_REG_RMW_BUFFER(ah);
257 for (i = 0; i < NUM_NF_READINGS; i++) {
258 if (chainmask & (1 << i)) {
259 s16 nfval;
260
261 if ((i >= AR5416_MAX_CHAINS) && !IS_CHAN_HT40(chan))
262 continue;
263
264 if (ah->nf_override)
265 nfval = ah->nf_override;
266 else if (h)
267 nfval = h[i].privNF;
268 else {
269 /* Try to get calibrated noise floor value */
270 nfval =
271 ath9k_hw_get_nf_limits(ah, chan)->cal[i];
272 if (nfval > -60 || nfval < -127)
273 nfval = default_nf;
274 }
275
276 REG_RMW(ah, ah->nf_regs[i],
277 (((u32) nfval << 1) & 0x1ff), 0x1ff);
278 }
279 }
280
281 /*
282 * stop NF cal if ongoing to ensure NF load completes immediately
283 * (or after end rx/tx frame if ongoing)
284 */
285 if (bb_agc_ctl & AR_PHY_AGC_CONTROL_NF) {
286 REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL(ah), AR_PHY_AGC_CONTROL_NF);
287 REG_RMW_BUFFER_FLUSH(ah);
288 ENABLE_REG_RMW_BUFFER(ah);
289 }
290
291 /*
292 * Load software filtered NF value into baseband internal minCCApwr
293 * variable.
294 */
295 REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL(ah),
296 AR_PHY_AGC_CONTROL_ENABLE_NF);
297 REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL(ah),
298 AR_PHY_AGC_CONTROL_NO_UPDATE_NF);
299 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah), AR_PHY_AGC_CONTROL_NF);
300 REG_RMW_BUFFER_FLUSH(ah);
301
302 /*
303 * Wait for load to complete, should be fast, a few 10s of us.
304 * The max delay was changed from an original 250us to 22.2 msec.
305 * This would increase timeout to the longest possible frame
306 * (11n max length 22.1 msec)
307 */
308 for (j = 0; j < 22200; j++) {
309 if ((REG_READ(ah, AR_PHY_AGC_CONTROL(ah)) &
310 AR_PHY_AGC_CONTROL_NF) == 0)
311 break;
312 udelay(10);
313 }
314
315 /*
316 * Restart NF so it can continue.
317 */
318 if (bb_agc_ctl & AR_PHY_AGC_CONTROL_NF) {
319 ENABLE_REG_RMW_BUFFER(ah);
320 if (bb_agc_ctl & AR_PHY_AGC_CONTROL_ENABLE_NF)
321 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah),
322 AR_PHY_AGC_CONTROL_ENABLE_NF);
323 if (bb_agc_ctl & AR_PHY_AGC_CONTROL_NO_UPDATE_NF)
324 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah),
325 AR_PHY_AGC_CONTROL_NO_UPDATE_NF);
326 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah), AR_PHY_AGC_CONTROL_NF);
327 REG_RMW_BUFFER_FLUSH(ah);
328 }
329
330 /*
331 * We timed out waiting for the noisefloor to load, probably due to an
332 * in-progress rx. Simply return here and allow the load plenty of time
333 * to complete before the next calibration interval. We need to avoid
334 * trying to load -50 (which happens below) while the previous load is
335 * still in progress as this can cause rx deafness. Instead by returning
336 * here, the baseband nf cal will just be capped by our present
337 * noisefloor until the next calibration timer.
338 */
339 if (j == 22200) {
340 ath_dbg(common, ANY,
341 "Timeout while waiting for nf to load: AR_PHY_AGC_CONTROL=0x%x\n",
342 REG_READ(ah, AR_PHY_AGC_CONTROL(ah)));
343 return -ETIMEDOUT;
344 }
345
346 /*
347 * Restore maxCCAPower register parameter again so that we're not capped
348 * by the median we just loaded. This will be initial (and max) value
349 * of next noise floor calibration the baseband does.
350 */
351 ENABLE_REG_RMW_BUFFER(ah);
352 for (i = 0; i < NUM_NF_READINGS; i++) {
353 if (chainmask & (1 << i)) {
354 if ((i >= AR5416_MAX_CHAINS) && !IS_CHAN_HT40(chan))
355 continue;
356
357 REG_RMW(ah, ah->nf_regs[i],
358 (((u32) (-50) << 1) & 0x1ff), 0x1ff);
359 }
360 }
361 REG_RMW_BUFFER_FLUSH(ah);
362
363 return 0;
364 }
365 EXPORT_SYMBOL(ath9k_hw_loadnf);
366
367
ath9k_hw_nf_sanitize(struct ath_hw * ah,s16 * nf)368 static void ath9k_hw_nf_sanitize(struct ath_hw *ah, s16 *nf)
369 {
370 struct ath_common *common = ath9k_hw_common(ah);
371 struct ath_nf_limits *limit;
372 int i;
373
374 if (IS_CHAN_2GHZ(ah->curchan))
375 limit = &ah->nf_2g;
376 else
377 limit = &ah->nf_5g;
378
379 for (i = 0; i < NUM_NF_READINGS; i++) {
380 if (!nf[i])
381 continue;
382
383 ath_dbg(common, CALIBRATE,
384 "NF calibrated [%s] [chain %d] is %d\n",
385 (i >= 3 ? "ext" : "ctl"), i % 3, nf[i]);
386
387 if (nf[i] > limit->max) {
388 ath_dbg(common, CALIBRATE,
389 "NF[%d] (%d) > MAX (%d), correcting to MAX\n",
390 i, nf[i], limit->max);
391 nf[i] = limit->max;
392 } else if (nf[i] < limit->min) {
393 ath_dbg(common, CALIBRATE,
394 "NF[%d] (%d) < MIN (%d), correcting to NOM\n",
395 i, nf[i], limit->min);
396 nf[i] = limit->nominal;
397 }
398 }
399 }
400
ath9k_hw_getnf(struct ath_hw * ah,struct ath9k_channel * chan)401 bool ath9k_hw_getnf(struct ath_hw *ah, struct ath9k_channel *chan)
402 {
403 struct ath_common *common = ath9k_hw_common(ah);
404 int16_t nf, nfThresh;
405 int16_t nfarray[NUM_NF_READINGS] = { 0 };
406 struct ath9k_nfcal_hist *h;
407 struct ieee80211_channel *c = chan->chan;
408 struct ath9k_hw_cal_data *caldata = ah->caldata;
409
410 if (REG_READ(ah, AR_PHY_AGC_CONTROL(ah)) & AR_PHY_AGC_CONTROL_NF) {
411 ath_dbg(common, CALIBRATE,
412 "NF did not complete in calibration window\n");
413 return false;
414 }
415
416 ath9k_hw_do_getnf(ah, nfarray);
417 ath9k_hw_nf_sanitize(ah, nfarray);
418 nf = nfarray[0];
419 if (ath9k_hw_get_nf_thresh(ah, c->band, &nfThresh)
420 && nf > nfThresh) {
421 ath_dbg(common, CALIBRATE,
422 "noise floor failed detected; detected %d, threshold %d\n",
423 nf, nfThresh);
424 }
425
426 if (!caldata) {
427 chan->noisefloor = nf;
428 return false;
429 }
430
431 h = caldata->nfCalHist;
432 clear_bit(NFCAL_PENDING, &caldata->cal_flags);
433 ath9k_hw_update_nfcal_hist_buffer(ah, caldata, nfarray);
434 chan->noisefloor = h[0].privNF;
435 ah->noise = ath9k_hw_getchan_noise(ah, chan, chan->noisefloor);
436 return true;
437 }
438 EXPORT_SYMBOL(ath9k_hw_getnf);
439
ath9k_init_nfcal_hist_buffer(struct ath_hw * ah,struct ath9k_channel * chan)440 void ath9k_init_nfcal_hist_buffer(struct ath_hw *ah,
441 struct ath9k_channel *chan)
442 {
443 struct ath9k_nfcal_hist *h;
444 int i, j, k = 0;
445
446 ah->caldata->channel = chan->channel;
447 ah->caldata->channelFlags = chan->channelFlags;
448 h = ah->caldata->nfCalHist;
449 for (i = 0; i < NUM_NF_READINGS; i++) {
450 h[i].currIndex = 0;
451 h[i].privNF = ath9k_hw_get_default_nf(ah, chan, k);
452 h[i].invalidNFcount = AR_PHY_CCA_FILTERWINDOW_LENGTH;
453 for (j = 0; j < ATH9K_NF_CAL_HIST_MAX; j++)
454 h[i].nfCalBuffer[j] = h[i].privNF;
455 if (++k >= AR5416_MAX_CHAINS)
456 k = 0;
457 }
458 }
459
460
ath9k_hw_bstuck_nfcal(struct ath_hw * ah)461 void ath9k_hw_bstuck_nfcal(struct ath_hw *ah)
462 {
463 struct ath9k_hw_cal_data *caldata = ah->caldata;
464
465 if (unlikely(!caldata))
466 return;
467
468 /*
469 * If beacons are stuck, the most likely cause is interference.
470 * Triggering a noise floor calibration at this point helps the
471 * hardware adapt to a noisy environment much faster.
472 * To ensure that we recover from stuck beacons quickly, let
473 * the baseband update the internal NF value itself, similar to
474 * what is being done after a full reset.
475 */
476 if (!test_bit(NFCAL_PENDING, &caldata->cal_flags))
477 ath9k_hw_start_nfcal(ah, true);
478 else if (!(REG_READ(ah, AR_PHY_AGC_CONTROL(ah)) & AR_PHY_AGC_CONTROL_NF))
479 ath9k_hw_getnf(ah, ah->curchan);
480
481 set_bit(NFCAL_INTF, &caldata->cal_flags);
482 }
483 EXPORT_SYMBOL(ath9k_hw_bstuck_nfcal);
484
485