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
24static 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 nfval = sort[j];
37 sort[j] = sort[j - 1];
38 sort[j - 1] = nfval;
39 }
40 }
41 }
42 nfval = sort[(ATH9K_NF_CAL_HIST_MAX - 1) >> 1];
43
44 return nfval;
45}
46
47static struct ath_nf_limits *ath9k_hw_get_nf_limits(struct ath_hw *ah,
48 struct ath9k_channel *chan)
49{
50 struct ath_nf_limits *limit;
51
52 if (!chan || IS_CHAN_2GHZ(chan))
53 limit = &ah->nf_2g;
54 else
55 limit = &ah->nf_5g;
56
57 return limit;
58}
59
60static s16 ath9k_hw_get_default_nf(struct ath_hw *ah,
61 struct ath9k_channel *chan,
62 int chain)
63{
64 s16 calib_nf = ath9k_hw_get_nf_limits(ah, chan)->cal[chain];
65
66 if (calib_nf)
67 return calib_nf;
68 else
69 return ath9k_hw_get_nf_limits(ah, chan)->nominal;
70}
71
72s16 ath9k_hw_getchan_noise(struct ath_hw *ah, struct ath9k_channel *chan,
73 s16 nf)
74{
75 s8 noise = ATH_DEFAULT_NOISE_FLOOR;
76
77 if (nf) {
78 s8 delta = nf - ATH9K_NF_CAL_NOISE_THRESH -
79 ath9k_hw_get_default_nf(ah, chan, chain: 0);
80 if (delta > 0)
81 noise += delta;
82 }
83 return noise;
84}
85EXPORT_SYMBOL(ath9k_hw_getchan_noise);
86
87static void ath9k_hw_update_nfcal_hist_buffer(struct ath_hw *ah,
88 struct ath9k_hw_cal_data *cal,
89 int16_t *nfarray)
90{
91 struct ath_common *common = ath9k_hw_common(ah);
92 struct ath_nf_limits *limit;
93 struct ath9k_nfcal_hist *h;
94 bool high_nf_mid = false;
95 u8 chainmask = (ah->rxchainmask << 3) | ah->rxchainmask;
96 int i;
97
98 h = cal->nfCalHist;
99 limit = ath9k_hw_get_nf_limits(ah, chan: ah->curchan);
100
101 for (i = 0; i < NUM_NF_READINGS; i++) {
102 if (!(chainmask & (1 << i)) ||
103 ((i >= AR5416_MAX_CHAINS) && !IS_CHAN_HT40(ah->curchan)))
104 continue;
105
106 h[i].nfCalBuffer[h[i].currIndex] = nfarray[i];
107
108 if (++h[i].currIndex >= ATH9K_NF_CAL_HIST_MAX)
109 h[i].currIndex = 0;
110
111 if (h[i].invalidNFcount > 0) {
112 h[i].invalidNFcount--;
113 h[i].privNF = nfarray[i];
114 } else {
115 h[i].privNF =
116 ath9k_hw_get_nf_hist_mid(nfCalBuffer: h[i].nfCalBuffer);
117 }
118
119 if (!h[i].privNF)
120 continue;
121
122 if (h[i].privNF > limit->max) {
123 high_nf_mid = true;
124
125 ath_dbg(common, CALIBRATE,
126 "NFmid[%d] (%d) > MAX (%d), %s\n",
127 i, h[i].privNF, limit->max,
128 (test_bit(NFCAL_INTF, &cal->cal_flags) ?
129 "not corrected (due to interference)" :
130 "correcting to MAX"));
131
132 /*
133 * Normally we limit the average noise floor by the
134 * hardware specific maximum here. However if we have
135 * encountered stuck beacons because of interference,
136 * we bypass this limit here in order to better deal
137 * with our environment.
138 */
139 if (!test_bit(NFCAL_INTF, &cal->cal_flags))
140 h[i].privNF = limit->max;
141 }
142 }
143
144 /*
145 * If the noise floor seems normal for all chains, assume that
146 * there is no significant interference in the environment anymore.
147 * Re-enable the enforcement of the NF maximum again.
148 */
149 if (!high_nf_mid)
150 clear_bit(nr: NFCAL_INTF, addr: &cal->cal_flags);
151}
152
153static bool ath9k_hw_get_nf_thresh(struct ath_hw *ah,
154 enum nl80211_band band,
155 int16_t *nft)
156{
157 switch (band) {
158 case NL80211_BAND_5GHZ:
159 *nft = (int8_t)ah->eep_ops->get_eeprom(ah, EEP_NFTHRESH_5);
160 break;
161 case NL80211_BAND_2GHZ:
162 *nft = (int8_t)ah->eep_ops->get_eeprom(ah, EEP_NFTHRESH_2);
163 break;
164 default:
165 BUG_ON(1);
166 return false;
167 }
168
169 return true;
170}
171
172void ath9k_hw_reset_calibration(struct ath_hw *ah,
173 struct ath9k_cal_list *currCal)
174{
175 int i;
176
177 ath9k_hw_setup_calibration(ah, currCal);
178
179 ah->cal_start_time = jiffies;
180 currCal->calState = CAL_RUNNING;
181
182 for (i = 0; i < AR5416_MAX_CHAINS; i++) {
183 ah->meas0.sign[i] = 0;
184 ah->meas1.sign[i] = 0;
185 ah->meas2.sign[i] = 0;
186 ah->meas3.sign[i] = 0;
187 }
188
189 ah->cal_samples = 0;
190}
191
192/* This is done for the currently configured channel */
193bool ath9k_hw_reset_calvalid(struct ath_hw *ah)
194{
195 struct ath_common *common = ath9k_hw_common(ah);
196 struct ath9k_cal_list *currCal = ah->cal_list_curr;
197
198 if (!ah->caldata)
199 return true;
200
201 if (!AR_SREV_9100(ah) && !AR_SREV_9160_10_OR_LATER(ah))
202 return true;
203
204 if (currCal == NULL)
205 return true;
206
207 if (currCal->calState != CAL_DONE) {
208 ath_dbg(common, CALIBRATE, "Calibration state incorrect, %d\n",
209 currCal->calState);
210 return true;
211 }
212
213 currCal = ah->cal_list;
214 do {
215 ath_dbg(common, CALIBRATE, "Resetting Cal %d state for channel %u\n",
216 currCal->calData->calType,
217 ah->curchan->chan->center_freq);
218
219 ah->caldata->CalValid &= ~currCal->calData->calType;
220 currCal->calState = CAL_WAITING;
221
222 currCal = currCal->calNext;
223 } while (currCal != ah->cal_list);
224
225 return false;
226}
227EXPORT_SYMBOL(ath9k_hw_reset_calvalid);
228
229void ath9k_hw_start_nfcal(struct ath_hw *ah, bool update)
230{
231 if (ah->caldata)
232 set_bit(nr: NFCAL_PENDING, addr: &ah->caldata->cal_flags);
233
234 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah),
235 AR_PHY_AGC_CONTROL_ENABLE_NF);
236
237 if (update)
238 REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL(ah),
239 AR_PHY_AGC_CONTROL_NO_UPDATE_NF);
240 else
241 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah),
242 AR_PHY_AGC_CONTROL_NO_UPDATE_NF);
243
244 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah), AR_PHY_AGC_CONTROL_NF);
245}
246
247int ath9k_hw_loadnf(struct ath_hw *ah, struct ath9k_channel *chan)
248{
249 struct ath9k_nfcal_hist *h = NULL;
250 unsigned i, j;
251 u8 chainmask = (ah->rxchainmask << 3) | ah->rxchainmask;
252 struct ath_common *common = ath9k_hw_common(ah);
253 s16 default_nf = ath9k_hw_get_nf_limits(ah, chan)->nominal;
254 u32 bb_agc_ctl = REG_READ(ah, AR_PHY_AGC_CONTROL(ah));
255
256 if (ah->caldata)
257 h = ah->caldata->nfCalHist;
258
259 ENABLE_REG_RMW_BUFFER(ah);
260 for (i = 0; i < NUM_NF_READINGS; i++) {
261 if (chainmask & (1 << i)) {
262 s16 nfval;
263
264 if ((i >= AR5416_MAX_CHAINS) && !IS_CHAN_HT40(chan))
265 continue;
266
267 if (ah->nf_override)
268 nfval = ah->nf_override;
269 else if (h)
270 nfval = h[i].privNF;
271 else {
272 /* Try to get calibrated noise floor value */
273 nfval =
274 ath9k_hw_get_nf_limits(ah, chan)->cal[i];
275 if (nfval > -60 || nfval < -127)
276 nfval = default_nf;
277 }
278
279 REG_RMW(ah, ah->nf_regs[i],
280 (((u32) nfval << 1) & 0x1ff), 0x1ff);
281 }
282 }
283
284 /*
285 * stop NF cal if ongoing to ensure NF load completes immediately
286 * (or after end rx/tx frame if ongoing)
287 */
288 if (bb_agc_ctl & AR_PHY_AGC_CONTROL_NF) {
289 REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL(ah), AR_PHY_AGC_CONTROL_NF);
290 REG_RMW_BUFFER_FLUSH(ah);
291 ENABLE_REG_RMW_BUFFER(ah);
292 }
293
294 /*
295 * Load software filtered NF value into baseband internal minCCApwr
296 * variable.
297 */
298 REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL(ah),
299 AR_PHY_AGC_CONTROL_ENABLE_NF);
300 REG_CLR_BIT(ah, AR_PHY_AGC_CONTROL(ah),
301 AR_PHY_AGC_CONTROL_NO_UPDATE_NF);
302 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah), AR_PHY_AGC_CONTROL_NF);
303 REG_RMW_BUFFER_FLUSH(ah);
304
305 /*
306 * Wait for load to complete, should be fast, a few 10s of us.
307 * The max delay was changed from an original 250us to 22.2 msec.
308 * This would increase timeout to the longest possible frame
309 * (11n max length 22.1 msec)
310 */
311 for (j = 0; j < 22200; j++) {
312 if ((REG_READ(ah, AR_PHY_AGC_CONTROL(ah)) &
313 AR_PHY_AGC_CONTROL_NF) == 0)
314 break;
315 udelay(10);
316 }
317
318 /*
319 * Restart NF so it can continue.
320 */
321 if (bb_agc_ctl & AR_PHY_AGC_CONTROL_NF) {
322 ENABLE_REG_RMW_BUFFER(ah);
323 if (bb_agc_ctl & AR_PHY_AGC_CONTROL_ENABLE_NF)
324 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah),
325 AR_PHY_AGC_CONTROL_ENABLE_NF);
326 if (bb_agc_ctl & AR_PHY_AGC_CONTROL_NO_UPDATE_NF)
327 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah),
328 AR_PHY_AGC_CONTROL_NO_UPDATE_NF);
329 REG_SET_BIT(ah, AR_PHY_AGC_CONTROL(ah), AR_PHY_AGC_CONTROL_NF);
330 REG_RMW_BUFFER_FLUSH(ah);
331 }
332
333 /*
334 * We timed out waiting for the noisefloor to load, probably due to an
335 * in-progress rx. Simply return here and allow the load plenty of time
336 * to complete before the next calibration interval. We need to avoid
337 * trying to load -50 (which happens below) while the previous load is
338 * still in progress as this can cause rx deafness. Instead by returning
339 * here, the baseband nf cal will just be capped by our present
340 * noisefloor until the next calibration timer.
341 */
342 if (j == 22200) {
343 ath_dbg(common, ANY,
344 "Timeout while waiting for nf to load: AR_PHY_AGC_CONTROL=0x%x\n",
345 REG_READ(ah, AR_PHY_AGC_CONTROL(ah)));
346 return -ETIMEDOUT;
347 }
348
349 /*
350 * Restore maxCCAPower register parameter again so that we're not capped
351 * by the median we just loaded. This will be initial (and max) value
352 * of next noise floor calibration the baseband does.
353 */
354 ENABLE_REG_RMW_BUFFER(ah);
355 for (i = 0; i < NUM_NF_READINGS; i++) {
356 if (chainmask & (1 << i)) {
357 if ((i >= AR5416_MAX_CHAINS) && !IS_CHAN_HT40(chan))
358 continue;
359
360 REG_RMW(ah, ah->nf_regs[i],
361 (((u32) (-50) << 1) & 0x1ff), 0x1ff);
362 }
363 }
364 REG_RMW_BUFFER_FLUSH(ah);
365
366 return 0;
367}
368EXPORT_SYMBOL(ath9k_hw_loadnf);
369
370
371static void ath9k_hw_nf_sanitize(struct ath_hw *ah, s16 *nf)
372{
373 struct ath_common *common = ath9k_hw_common(ah);
374 struct ath_nf_limits *limit;
375 int i;
376
377 if (IS_CHAN_2GHZ(ah->curchan))
378 limit = &ah->nf_2g;
379 else
380 limit = &ah->nf_5g;
381
382 for (i = 0; i < NUM_NF_READINGS; i++) {
383 if (!nf[i])
384 continue;
385
386 ath_dbg(common, CALIBRATE,
387 "NF calibrated [%s] [chain %d] is %d\n",
388 (i >= 3 ? "ext" : "ctl"), i % 3, nf[i]);
389
390 if (nf[i] > limit->max) {
391 ath_dbg(common, CALIBRATE,
392 "NF[%d] (%d) > MAX (%d), correcting to MAX\n",
393 i, nf[i], limit->max);
394 nf[i] = limit->max;
395 } else if (nf[i] < limit->min) {
396 ath_dbg(common, CALIBRATE,
397 "NF[%d] (%d) < MIN (%d), correcting to NOM\n",
398 i, nf[i], limit->min);
399 nf[i] = limit->nominal;
400 }
401 }
402}
403
404bool ath9k_hw_getnf(struct ath_hw *ah, struct ath9k_channel *chan)
405{
406 struct ath_common *common = ath9k_hw_common(ah);
407 int16_t nf, nfThresh;
408 int16_t nfarray[NUM_NF_READINGS] = { 0 };
409 struct ath9k_nfcal_hist *h;
410 struct ieee80211_channel *c = chan->chan;
411 struct ath9k_hw_cal_data *caldata = ah->caldata;
412
413 if (REG_READ(ah, AR_PHY_AGC_CONTROL(ah)) & AR_PHY_AGC_CONTROL_NF) {
414 ath_dbg(common, CALIBRATE,
415 "NF did not complete in calibration window\n");
416 return false;
417 }
418
419 ath9k_hw_do_getnf(ah, nfarray);
420 ath9k_hw_nf_sanitize(ah, nf: nfarray);
421 nf = nfarray[0];
422 if (ath9k_hw_get_nf_thresh(ah, band: c->band, nft: &nfThresh)
423 && nf > nfThresh) {
424 ath_dbg(common, CALIBRATE,
425 "noise floor failed detected; detected %d, threshold %d\n",
426 nf, nfThresh);
427 }
428
429 if (!caldata) {
430 chan->noisefloor = nf;
431 return false;
432 }
433
434 h = caldata->nfCalHist;
435 clear_bit(nr: NFCAL_PENDING, addr: &caldata->cal_flags);
436 ath9k_hw_update_nfcal_hist_buffer(ah, cal: caldata, nfarray);
437 chan->noisefloor = h[0].privNF;
438 ah->noise = ath9k_hw_getchan_noise(ah, chan, chan->noisefloor);
439 return true;
440}
441EXPORT_SYMBOL(ath9k_hw_getnf);
442
443void ath9k_init_nfcal_hist_buffer(struct ath_hw *ah,
444 struct ath9k_channel *chan)
445{
446 struct ath9k_nfcal_hist *h;
447 int i, j, k = 0;
448
449 ah->caldata->channel = chan->channel;
450 ah->caldata->channelFlags = chan->channelFlags;
451 h = ah->caldata->nfCalHist;
452 for (i = 0; i < NUM_NF_READINGS; i++) {
453 h[i].currIndex = 0;
454 h[i].privNF = ath9k_hw_get_default_nf(ah, chan, chain: k);
455 h[i].invalidNFcount = AR_PHY_CCA_FILTERWINDOW_LENGTH;
456 for (j = 0; j < ATH9K_NF_CAL_HIST_MAX; j++)
457 h[i].nfCalBuffer[j] = h[i].privNF;
458 if (++k >= AR5416_MAX_CHAINS)
459 k = 0;
460 }
461}
462
463
464void ath9k_hw_bstuck_nfcal(struct ath_hw *ah)
465{
466 struct ath9k_hw_cal_data *caldata = ah->caldata;
467
468 if (unlikely(!caldata))
469 return;
470
471 /*
472 * If beacons are stuck, the most likely cause is interference.
473 * Triggering a noise floor calibration at this point helps the
474 * hardware adapt to a noisy environment much faster.
475 * To ensure that we recover from stuck beacons quickly, let
476 * the baseband update the internal NF value itself, similar to
477 * what is being done after a full reset.
478 */
479 if (!test_bit(NFCAL_PENDING, &caldata->cal_flags))
480 ath9k_hw_start_nfcal(ah, update: true);
481 else if (!(REG_READ(ah, AR_PHY_AGC_CONTROL(ah)) & AR_PHY_AGC_CONTROL_NF))
482 ath9k_hw_getnf(ah, ah->curchan);
483
484 set_bit(nr: NFCAL_INTF, addr: &caldata->cal_flags);
485}
486EXPORT_SYMBOL(ath9k_hw_bstuck_nfcal);
487
488

source code of linux/drivers/net/wireless/ath/ath9k/calib.c