aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/net/wireless/iwlwifi/iwl-calib.c
blob: f1fd00b1a65da016521ab02a9f89d5de012942f1 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
/******************************************************************************
 *
 * This file is provided under a dual BSD/GPLv2 license.  When using or
 * redistributing this file, you may do so under either license.
 *
 * GPL LICENSE SUMMARY
 *
 * Copyright(c) 2008 - 2010 Intel Corporation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of version 2 of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
 * USA
 *
 * The full GNU General Public License is included in this distribution
 * in the file called LICENSE.GPL.
 *
 * Contact Information:
 *  Intel Linux Wireless <ilw@linux.intel.com>
 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
 *
 * BSD LICENSE
 *
 * Copyright(c) 2005 - 2010 Intel Corporation. All rights reserved.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in
 *    the documentation and/or other materials provided with the
 *    distribution.
 *  * Neither the name Intel Corporation nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *****************************************************************************/

#include <linux/slab.h>
#include <net/mac80211.h>

#include "iwl-dev.h"
#include "iwl-core.h"
#include "iwl-calib.h"

/*****************************************************************************
 * INIT calibrations framework
 *****************************************************************************/

struct statistics_general_data {
	u32 beacon_silence_rssi_a;
	u32 beacon_silence_rssi_b;
	u32 beacon_silence_rssi_c;
	u32 beacon_energy_a;
	u32 beacon_energy_b;
	u32 beacon_energy_c;
};

int iwl_send_calib_results(struct iwl_priv *priv)
{
	int ret = 0;
	int i = 0;

	struct iwl_host_cmd hcmd = {
		.id = REPLY_PHY_CALIBRATION_CMD,
		.flags = CMD_SIZE_HUGE,
	};

	for (i = 0; i < IWL_CALIB_MAX; i++) {
		if ((BIT(i) & priv->hw_params.calib_init_cfg) &&
		    priv->calib_results[i].buf) {
			hcmd.len = priv->calib_results[i].buf_len;
			hcmd.data = priv->calib_results[i].buf;
			ret = iwl_send_cmd_sync(priv, &hcmd);
			if (ret)
				goto err;
		}
	}

	return 0;
err:
	IWL_ERR(priv, "Error %d iteration %d\n", ret, i);
	return ret;
}
EXPORT_SYMBOL(iwl_send_calib_results);

int iwl_calib_set(struct iwl_calib_result *res, const u8 *buf, int len)
{
	if (res->buf_len != len) {
		kfree(res->buf);
		res->buf = kzalloc(len, GFP_ATOMIC);
	}
	if (unlikely(res->buf == NULL))
		return -ENOMEM;

	res->buf_len = len;
	memcpy(res->buf, buf, len);
	return 0;
}
EXPORT_SYMBOL(iwl_calib_set);

void iwl_calib_free_results(struct iwl_priv *priv)
{
	int i;

	for (i = 0; i < IWL_CALIB_MAX; i++) {
		kfree(priv->calib_results[i].buf);
		priv->calib_results[i].buf = NULL;
		priv->calib_results[i].buf_len = 0;
	}
}
EXPORT_SYMBOL(iwl_calib_free_results);

/*****************************************************************************
 * RUNTIME calibrations framework
 *****************************************************************************/

/* "false alarms" are signals that our DSP tries to lock onto,
 *   but then determines that they are either noise, or transmissions
 *   from a distant wireless network (also "noise", really) that get
 *   "stepped on" by stronger transmissions within our own network.
 * This algorithm attempts to set a sensitivity level that is high
 *   enough to receive all of our own network traffic, but not so
 *   high that our DSP gets too busy trying to lock onto non-network
 *   activity/noise. */
static int iwl_sens_energy_cck(struct iwl_priv *priv,
				   u32 norm_fa,
				   u32 rx_enable_time,
				   struct statistics_general_data *rx_info)
{
	u32 max_nrg_cck = 0;
	int i = 0;
	u8 max_silence_rssi = 0;
	u32 silence_ref = 0;
	u8 silence_rssi_a = 0;
	u8 silence_rssi_b = 0;
	u8 silence_rssi_c = 0;
	u32 val;

	/* "false_alarms" values below are cross-multiplications to assess the
	 *   numbers of false alarms within the measured period of actual Rx
	 *   (Rx is off when we're txing), vs the min/max expected false alarms
	 *   (some should be expected if rx is sensitive enough) in a
	 *   hypothetical listening period of 200 time units (TU), 204.8 msec:
	 *
	 * MIN_FA/fixed-time < false_alarms/actual-rx-time < MAX_FA/beacon-time
	 *
	 * */
	u32 false_alarms = norm_fa * 200 * 1024;
	u32 max_false_alarms = MAX_FA_CCK * rx_enable_time;
	u32 min_false_alarms = MIN_FA_CCK * rx_enable_time;
	struct iwl_sensitivity_data *data = NULL;
	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;

	data = &(priv->sensitivity_data);

	data->nrg_auto_corr_silence_diff = 0;

	/* Find max silence rssi among all 3 receivers.
	 * This is background noise, which may include transmissions from other
	 *    networks, measured during silence before our network's beacon */
	silence_rssi_a = (u8)((rx_info->beacon_silence_rssi_a &
			    ALL_BAND_FILTER) >> 8);
	silence_rssi_b = (u8)((rx_info->beacon_silence_rssi_b &
			    ALL_BAND_FILTER) >> 8);
	silence_rssi_c = (u8)((rx_info->beacon_silence_rssi_c &
			    ALL_BAND_FILTER) >> 8);

	val = max(silence_rssi_b, silence_rssi_c);
	max_silence_rssi = max(silence_rssi_a, (u8) val);

	/* Store silence rssi in 20-beacon history table */
	data->nrg_silence_rssi[data->nrg_silence_idx] = max_silence_rssi;
	data->nrg_silence_idx++;
	if (data->nrg_silence_idx >= NRG_NUM_PREV_STAT_L)
		data->nrg_silence_idx = 0;

	/* Find max silence rssi across 20 beacon history */
	for (i = 0; i < NRG_NUM_PREV_STAT_L; i++) {
		val = data->nrg_silence_rssi[i];
		silence_ref = max(silence_ref, val);
	}
	IWL_DEBUG_CALIB(priv, "silence a %u, b %u, c %u, 20-bcn max %u\n",
			silence_rssi_a, silence_rssi_b, silence_rssi_c,
			silence_ref);

	/* Find max rx energy (min value!) among all 3 receivers,
	 *   measured during beacon frame.
	 * Save it in 10-beacon history table. */
	i = data->nrg_energy_idx;
	val = min(rx_info->beacon_energy_b, rx_info->beacon_energy_c);
	data->nrg_value[i] = min(rx_info->beacon_energy_a, val);

	data->nrg_energy_idx++;
	if (data->nrg_energy_idx >= 10)
		data->nrg_energy_idx = 0;

	/* Find min rx energy (max value) across 10 beacon history.
	 * This is the minimum signal level that we want to receive well.
	 * Add backoff (margin so we don't miss slightly lower energy frames).
	 * This establishes an upper bound (min value) for energy threshold. */
	max_nrg_cck = data->nrg_value[0];
	for (i = 1; i < 10; i++)
		max_nrg_cck = (u32) max(max_nrg_cck, (data->nrg_value[i]));
	max_nrg_cck += 6;

	IWL_DEBUG_CALIB(priv, "rx energy a %u, b %u, c %u, 10-bcn max/min %u\n",
			rx_info->beacon_energy_a, rx_info->beacon_energy_b,
			rx_info->beacon_energy_c, max_nrg_cck - 6);

	/* Count number of consecutive beacons with fewer-than-desired
	 *   false alarms. */
	if (false_alarms < min_false_alarms)
		data->num_in_cck_no_fa++;
	else
		data->num_in_cck_no_fa = 0;
	IWL_DEBUG_CALIB(priv, "consecutive bcns with few false alarms = %u\n",
			data->num_in_cck_no_fa);

	/* If we got too many false alarms this time, reduce sensitivity */
	if ((false_alarms > max_false_alarms) &&
		(data->auto_corr_cck > AUTO_CORR_MAX_TH_CCK)) {
		IWL_DEBUG_CALIB(priv, "norm FA %u > max FA %u\n",
		     false_alarms, max_false_alarms);
		IWL_DEBUG_CALIB(priv, "... reducing sensitivity\n");
		data->nrg_curr_state = IWL_FA_TOO_MANY;
		/* Store for "fewer than desired" on later beacon */
		data->nrg_silence_ref = silence_ref;

		/* increase energy threshold (reduce nrg value)
		 *   to decrease sensitivity */
		data->nrg_th_cck = data->nrg_th_cck - NRG_STEP_CCK;
	/* Else if we got fewer than desired, increase sensitivity */
	} else if (false_alarms < min_false_alarms) {
		data->nrg_curr_state = IWL_FA_TOO_FEW;

		/* Compare silence level with silence level for most recent
		 *   healthy number or too many false alarms */
		data->nrg_auto_corr_silence_diff = (s32)data->nrg_silence_ref -
						   (s32)silence_ref;

		IWL_DEBUG_CALIB(priv, "norm FA %u < min FA %u, silence diff %d\n",
			 false_alarms, min_false_alarms,
			 data->nrg_auto_corr_silence_diff);

		/* Increase value to increase sensitivity, but only if:
		 * 1a) previous beacon did *not* have *too many* false alarms
		 * 1b) AND there's a significant difference in Rx levels
		 *      from a previous beacon with too many, or healthy # FAs
		 * OR 2) We've seen a lot of beacons (100) with too few
		 *       false alarms */
		if ((data->nrg_prev_state != IWL_FA_TOO_MANY) &&
			((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
			(data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {

			IWL_DEBUG_CALIB(priv, "... increasing sensitivity\n");
			/* Increase nrg value to increase sensitivity */
			val = data->nrg_th_cck + NRG_STEP_CCK;
			data->nrg_th_cck = min((u32)ranges->min_nrg_cck, val);
		} else {
			IWL_DEBUG_CALIB(priv, "... but not changing sensitivity\n");
		}

	/* Else we got a healthy number of false alarms, keep status quo */
	} else {
		IWL_DEBUG_CALIB(priv, " FA in safe zone\n");
		data->nrg_curr_state = IWL_FA_GOOD_RANGE;

		/* Store for use in "fewer than desired" with later beacon */
		data->nrg_silence_ref = silence_ref;

		/* If previous beacon had too many false alarms,
		 *   give it some extra margin by reducing sensitivity again
		 *   (but don't go below measured energy of desired Rx) */
		if (IWL_FA_TOO_MANY == data->nrg_prev_state) {
			IWL_DEBUG_CALIB(priv, "... increasing margin\n");
			if (data->nrg_th_cck > (max_nrg_cck + NRG_MARGIN))
				data->nrg_th_cck -= NRG_MARGIN;
			else
				data->nrg_th_cck = max_nrg_cck;
		}
	}

	/* Make sure the energy threshold does not go above the measured
	 * energy of the desired Rx signals (reduced by backoff margin),
	 * or else we might start missing Rx frames.
	 * Lower value is higher energy, so we use max()!
	 */
	data->nrg_th_cck = max(max_nrg_cck, data->nrg_th_cck);
	IWL_DEBUG_CALIB(priv, "new nrg_th_cck %u\n", data->nrg_th_cck);

	data->nrg_prev_state = data->nrg_curr_state;

	/* Auto-correlation CCK algorithm */
	if (false_alarms > min_false_alarms) {

		/* increase auto_corr values to decrease sensitivity
		 * so the DSP won't be disturbed by the noise
		 */
		if (data->auto_corr_cck < AUTO_CORR_MAX_TH_CCK)
			data->auto_corr_cck = AUTO_CORR_MAX_TH_CCK + 1;
		else {
			val = data->auto_corr_cck + AUTO_CORR_STEP_CCK;
			data->auto_corr_cck =
				min((u32)ranges->auto_corr_max_cck, val);
		}
		val = data->auto_corr_cck_mrc + AUTO_CORR_STEP_CCK;
		data->auto_corr_cck_mrc =
			min((u32)ranges->auto_corr_max_cck_mrc, val);
	} else if ((false_alarms < min_false_alarms) &&
	   ((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
	   (data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {

		/* Decrease auto_corr values to increase sensitivity */
		val = data->auto_corr_cck - AUTO_CORR_STEP_CCK;
		data->auto_corr_cck =
			max((u32)ranges->auto_corr_min_cck, val);
		val = data->auto_corr_cck_mrc - AUTO_CORR_STEP_CCK;
		data->auto_corr_cck_mrc =
			max((u32)ranges->auto_corr_min_cck_mrc, val);
	}

	return 0;
}


static int iwl_sens_auto_corr_ofdm(struct iwl_priv *priv,
				       u32 norm_fa,
				       u32 rx_enable_time)
{
	u32 val;
	u32 false_alarms = norm_fa * 200 * 1024;
	u32 max_false_alarms = MAX_FA_OFDM * rx_enable_time;
	u32 min_false_alarms = MIN_FA_OFDM * rx_enable_time;
	struct iwl_sensitivity_data *data = NULL;
	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;

	data = &(priv->sensitivity_data);

	/* If we got too many false alarms this time, reduce sensitivity */
	if (false_alarms > max_false_alarms) {

		IWL_DEBUG_CALIB(priv, "norm FA %u > max FA %u)\n",
			     false_alarms, max_false_alarms);

		val = data->auto_corr_ofdm + AUTO_CORR_STEP_OFDM;
		data->auto_corr_ofdm =
			min((u32)ranges->auto_corr_max_ofdm, val);

		val = data->auto_corr_ofdm_mrc + AUTO_CORR_STEP_OFDM;
		data->auto_corr_ofdm_mrc =
			min((u32)ranges->auto_corr_max_ofdm_mrc, val);

		val = data->auto_corr_ofdm_x1 + AUTO_CORR_STEP_OFDM;
		data->auto_corr_ofdm_x1 =
			min((u32)ranges->auto_corr_max_ofdm_x1, val);

		val = data->auto_corr_ofdm_mrc_x1 + AUTO_CORR_STEP_OFDM;
		data->auto_corr_ofdm_mrc_x1 =
			min((u32)ranges->auto_corr_max_ofdm_mrc_x1, val);
	}

	/* Else if we got fewer than desired, increase sensitivity */
	else if (false_alarms < min_false_alarms) {

		IWL_DEBUG_CALIB(priv, "norm FA %u < min FA %u\n",
			     false_alarms, min_false_alarms);

		val = data->auto_corr_ofdm - AUTO_CORR_STEP_OFDM;
		data->auto_corr_ofdm =
			max((u32)ranges->auto_corr_min_ofdm, val);

		val = data->auto_corr_ofdm_mrc - AUTO_CORR_STEP_OFDM;
		data->auto_corr_ofdm_mrc =
			max((u32)ranges->auto_corr_min_ofdm_mrc, val);

		val = data->auto_corr_ofdm_x1 - AUTO_CORR_STEP_OFDM;
		data->auto_corr_ofdm_x1 =
			max((u32)ranges->auto_corr_min_ofdm_x1, val);

		val = data->auto_corr_ofdm_mrc_x1 - AUTO_CORR_STEP_OFDM;
		data->auto_corr_ofdm_mrc_x1 =
			max((u32)ranges->auto_corr_min_ofdm_mrc_x1, val);
	} else {
		IWL_DEBUG_CALIB(priv, "min FA %u < norm FA %u < max FA %u OK\n",
			 min_false_alarms, false_alarms, max_false_alarms);
	}
	return 0;
}

/* Prepare a SENSITIVITY_CMD, send to uCode if values have changed */
static int iwl_sensitivity_write(struct iwl_priv *priv)
{
	struct iwl_sensitivity_cmd cmd ;
	struct iwl_sensitivity_data *data = NULL;
	struct iwl_host_cmd cmd_out = {
		.id = SENSITIVITY_CMD,
		.len = sizeof(struct iwl_sensitivity_cmd),
		.flags = CMD_ASYNC,
		.data = &cmd,
	};

	data = &(priv->sensitivity_data);

	memset(&cmd, 0, sizeof(cmd));

	cmd.table[HD_AUTO_CORR32_X4_TH_ADD_MIN_INDEX] =
				cpu_to_le16((u16)data->auto_corr_ofdm);
	cmd.table[HD_AUTO_CORR32_X4_TH_ADD_MIN_MRC_INDEX] =
				cpu_to_le16((u16)data->auto_corr_ofdm_mrc);
	cmd.table[HD_AUTO_CORR32_X1_TH_ADD_MIN_INDEX] =
				cpu_to_le16((u16)data->auto_corr_ofdm_x1);
	cmd.table[HD_AUTO_CORR32_X1_TH_ADD_MIN_MRC_INDEX] =
				cpu_to_le16((u16)data->auto_corr_ofdm_mrc_x1);

	cmd.table[HD_AUTO_CORR40_X4_TH_ADD_MIN_INDEX] =
				cpu_to_le16((u16)data->auto_corr_cck);
	cmd.table[HD_AUTO_CORR40_X4_TH_ADD_MIN_MRC_INDEX] =
				cpu_to_le16((u16)data->auto_corr_cck_mrc);

	cmd.table[HD_MIN_ENERGY_CCK_DET_INDEX] =
				cpu_to_le16((u16)data->nrg_th_cck);
	cmd.table[HD_MIN_ENERGY_OFDM_DET_INDEX] =
				cpu_to_le16((u16)data->nrg_th_ofdm);

	cmd.table[HD_BARKER_CORR_TH_ADD_MIN_INDEX] =
				cpu_to_le16(data->barker_corr_th_min);
	cmd.table[HD_BARKER_CORR_TH_ADD_MIN_MRC_INDEX] =
				cpu_to_le16(data->barker_corr_th_min_mrc);
	cmd.table[HD_OFDM_ENERGY_TH_IN_INDEX] =
				cpu_to_le16(data->nrg_th_cca);

	IWL_DEBUG_CALIB(priv, "ofdm: ac %u mrc %u x1 %u mrc_x1 %u thresh %u\n",
			data->auto_corr_ofdm, data->auto_corr_ofdm_mrc,
			data->auto_corr_ofdm_x1, data->auto_corr_ofdm_mrc_x1,
			data->nrg_th_ofdm);

	IWL_DEBUG_CALIB(priv, "cck: ac %u mrc %u thresh %u\n",
			data->auto_corr_cck, data->auto_corr_cck_mrc,
			data->nrg_th_cck);

	/* Update uCode's "work" table, and copy it to DSP */
	cmd.control = SENSITIVITY_CMD_CONTROL_WORK_TABLE;

	/* Don't send command to uCode if nothing has changed */
	if (!memcmp(&cmd.table[0], &(priv->sensitivity_tbl[0]),
		    sizeof(u16)*HD_TABLE_SIZE)) {
		IWL_DEBUG_CALIB(priv, "No change in SENSITIVITY_CMD\n");
		return 0;
	}

	/* Copy table for comparison next time */
	memcpy(&(priv->sensitivity_tbl[0]), &(cmd.table[0]),
	       sizeof(u16)*HD_TABLE_SIZE);

	return iwl_send_cmd(priv, &cmd_out);
}

void iwl_init_sensitivity(struct iwl_priv *priv)
{
	int ret = 0;
	int i;
	struct iwl_sensitivity_data *data = NULL;
	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;

	if (priv->disable_sens_cal)
		return;

	IWL_DEBUG_CALIB(priv, "Start iwl_init_sensitivity\n");

	/* Clear driver's sensitivity algo data */
	data = &(priv->sensitivity_data);

	if (ranges == NULL)
		return;

	memset(data, 0, sizeof(struct iwl_sensitivity_data));

	data->num_in_cck_no_fa = 0;
	data->nrg_curr_state = IWL_FA_TOO_MANY;
	data->nrg_prev_state = IWL_FA_TOO_MANY;
	data->nrg_silence_ref = 0;
	data->nrg_silence_idx = 0;
	data->nrg_energy_idx = 0;

	for (i = 0; i < 10; i++)
		data->nrg_value[i] = 0;

	for (i = 0; i < NRG_NUM_PREV_STAT_L; i++)
		data->nrg_silence_rssi[i] = 0;

	data->auto_corr_ofdm =  ranges->auto_corr_min_ofdm;
	data->auto_corr_ofdm_mrc = ranges->auto_corr_min_ofdm_mrc;
	data->auto_corr_ofdm_x1  = ranges->auto_corr_min_ofdm_x1;
	data->auto_corr_ofdm_mrc_x1 = ranges->auto_corr_min_ofdm_mrc_x1;
	data->auto_corr_cck = AUTO_CORR_CCK_MIN_VAL_DEF;
	data->auto_corr_cck_mrc = ranges->auto_corr_min_cck_mrc;
	data->nrg_th_cck = ranges->nrg_th_cck;
	data->nrg_th_ofdm = ranges->nrg_th_ofdm;
	data->barker_corr_th_min = ranges->barker_corr_th_min;
	data->barker_corr_th_min_mrc = ranges->barker_corr_th_min_mrc;
	data->nrg_th_cca = ranges->nrg_th_cca;

	data->last_bad_plcp_cnt_ofdm = 0;
	data->last_fa_cnt_ofdm = 0;
	data->last_bad_plcp_cnt_cck = 0;
	data->last_fa_cnt_cck = 0;

	ret |= iwl_sensitivity_write(priv);
	IWL_DEBUG_CALIB(priv, "<<return 0x%X\n", ret);
}
EXPORT_SYMBOL(iwl_init_sensitivity);

void iwl_sensitivity_calibration(struct iwl_priv *priv,
				    struct iwl_notif_statistics *resp)
{
	u32 rx_enable_time;
	u32 fa_cck;
	u32 fa_ofdm;
	u32 bad_plcp_cck;
	u32 bad_plcp_ofdm;
	u32 norm_fa_ofdm;
	u32 norm_fa_cck;
	struct iwl_sensitivity_data *data = NULL;
	struct statistics_rx_non_phy *rx_info = &(resp->rx.general);
	struct statistics_rx *statistics = &(resp->rx);
	unsigned long flags;
	struct statistics_general_data statis;

	if (priv->disable_sens_cal)
		return;

	data = &(priv->sensitivity_data);

	if (!iwl_is_associated(priv)) {
		IWL_DEBUG_CALIB(priv, "<< - not associated\n");
		return;
	}

	spin_lock_irqsave(&priv->lock, flags);
	if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
		IWL_DEBUG_CALIB(priv, "<< invalid data.\n");
		spin_unlock_irqrestore(&priv->lock, flags);
		return;
	}

	/* Extract Statistics: */
	rx_enable_time = le32_to_cpu(rx_info->channel_load);
	fa_cck = le32_to_cpu(statistics->cck.false_alarm_cnt);
	fa_ofdm = le32_to_cpu(statistics->ofdm.false_alarm_cnt);
	bad_plcp_cck = le32_to_cpu(statistics->cck.plcp_err);
	bad_plcp_ofdm = le32_to_cpu(statistics->ofdm.plcp_err);

	statis.beacon_silence_rssi_a =
			le32_to_cpu(statistics->general.beacon_silence_rssi_a);
	statis.beacon_silence_rssi_b =
			le32_to_cpu(statistics->general.beacon_silence_rssi_b);
	statis.beacon_silence_rssi_c =
			le32_to_cpu(statistics->general.beacon_silence_rssi_c);
	statis.beacon_energy_a =
			le32_to_cpu(statistics->general.beacon_energy_a);
	statis.beacon_energy_b =
			le32_to_cpu(statistics->general.beacon_energy_b);
	statis.beacon_energy_c =
			le32_to_cpu(statistics->general.beacon_energy_c);

	spin_unlock_irqrestore(&priv->lock, flags);

	IWL_DEBUG_CALIB(priv, "rx_enable_time = %u usecs\n", rx_enable_time);

	if (!rx_enable_time) {
		IWL_DEBUG_CALIB(priv, "<< RX Enable Time == 0!\n");
		return;
	}

	/* These statistics increase monotonically, and do not reset
	 *   at each beacon.  Calculate difference from last value, or just
	 *   use the new statistics value if it has reset or wrapped around. */
	if (data->last_bad_plcp_cnt_cck > bad_plcp_cck)
		data->last_bad_plcp_cnt_cck = bad_plcp_cck;
	else {
		bad_plcp_cck -= data->last_bad_plcp_cnt_cck;
		data->last_bad_plcp_cnt_cck += bad_plcp_cck;
	}

	if (data->last_bad_plcp_cnt_ofdm > bad_plcp_ofdm)
		data->last_bad_plcp_cnt_ofdm = bad_plcp_ofdm;
	else {
		bad_plcp_ofdm -= data->last_bad_plcp_cnt_ofdm;
		data->last_bad_plcp_cnt_ofdm += bad_plcp_ofdm;
	}

	if (data->last_fa_cnt_ofdm > fa_ofdm)
		data->last_fa_cnt_ofdm = fa_ofdm;
	else {
		fa_ofdm -= data->last_fa_cnt_ofdm;
		data->last_fa_cnt_ofdm += fa_ofdm;
	}

	if (data->last_fa_cnt_cck > fa_cck)
		data->last_fa_cnt_cck = fa_cck;
	else {
		fa_cck -= data->last_fa_cnt_cck;
		data->last_fa_cnt_cck += fa_cck;
	}

	/* Total aborted signal locks */
	norm_fa_ofdm = fa_ofdm + bad_plcp_ofdm;
	norm_fa_cck = fa_cck + bad_plcp_cck;

	IWL_DEBUG_CALIB(priv, "cck: fa %u badp %u  ofdm: fa %u badp %u\n", fa_cck,
			bad_plcp_cck, fa_ofdm, bad_plcp_ofdm);

	iwl_sens_auto_corr_ofdm(priv, norm_fa_ofdm, rx_enable_time);
	iwl_sens_energy_cck(priv, norm_fa_cck, rx_enable_time, &statis);
	iwl_sensitivity_write(priv);

	return;
}
EXPORT_SYMBOL(iwl_sensitivity_calibration);

static inline u8 find_first_chain(u8 mask)
{
	if (mask & ANT_A)
		return CHAIN_A;
	if (mask & ANT_B)
		return CHAIN_B;
	return CHAIN_C;
}

/*
 * Accumulate 20 beacons of signal and noise statistics for each of
 *   3 receivers/antennas/rx-chains, then figure out:
 * 1)  Which antennas are connected.
 * 2)  Differential rx gain settings to balance the 3 receivers.
 */
void iwl_chain_noise_calibration(struct iwl_priv *priv,
				 struct iwl_notif_statistics *stat_resp)
{
	struct iwl_chain_noise_data *data = NULL;

	u32 chain_noise_a;
	u32 chain_noise_b;
	u32 chain_noise_c;
	u32 chain_sig_a;
	u32 chain_sig_b;
	u32 chain_sig_c;
	u32 average_sig[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
	u32 average_noise[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
	u32 max_average_sig;
	u16 max_average_sig_antenna_i;
	u32 min_average_noise = MIN_AVERAGE_NOISE_MAX_VALUE;
	u16 min_average_noise_antenna_i = INITIALIZATION_VALUE;
	u16 i = 0;
	u16 rxon_chnum = INITIALIZATION_VALUE;
	u16 stat_chnum = INITIALIZATION_VALUE;
	u8 rxon_band24;
	u8 stat_band24;
	u32 active_chains = 0;
	u8 num_tx_chains;
	unsigned long flags;
	struct statistics_rx_non_phy *rx_info = &(stat_resp->rx.general);
	u8 first_chain;

	if (priv->disable_chain_noise_cal)
		return;

	data = &(priv->chain_noise_data);

	/*
	 * Accumulate just the first "chain_noise_num_beacons" after
	 * the first association, then we're done forever.
	 */
	if (data->state != IWL_CHAIN_NOISE_ACCUMULATE) {
		if (data->state == IWL_CHAIN_NOISE_ALIVE)
			IWL_DEBUG_CALIB(priv, "Wait for noise calib reset\n");
		return;
	}

	spin_lock_irqsave(&priv->lock, flags);
	if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
		IWL_DEBUG_CALIB(priv, " << Interference data unavailable\n");
		spin_unlock_irqrestore(&priv->lock, flags);
		return;
	}

	rxon_band24 = !!(priv->staging_rxon.flags & RXON_FLG_BAND_24G_MSK);
	rxon_chnum = le16_to_cpu(priv->staging_rxon.channel);
	stat_band24 = !!(stat_resp->flag & STATISTICS_REPLY_FLG_BAND_24G_MSK);
	stat_chnum = le32_to_cpu(stat_resp->flag) >> 16;

	/* Make sure we accumulate data for just the associated channel
	 *   (even if scanning). */
	if ((rxon_chnum != stat_chnum) || (rxon_band24 != stat_band24)) {
		IWL_DEBUG_CALIB(priv, "Stats not from chan=%d, band24=%d\n",
				rxon_chnum, rxon_band24);
		spin_unlock_irqrestore(&priv->lock, flags);
		return;
	}

	/*
	 *  Accumulate beacon statistics values across
	 * "chain_noise_num_beacons"
	 */
	chain_noise_a = le32_to_cpu(rx_info->beacon_silence_rssi_a) &
				IN_BAND_FILTER;
	chain_noise_b = le32_to_cpu(rx_info->beacon_silence_rssi_b) &
				IN_BAND_FILTER;
	chain_noise_c = le32_to_cpu(rx_info->beacon_silence_rssi_c) &
				IN_BAND_FILTER;

	chain_sig_a = le32_to_cpu(rx_info->beacon_rssi_a) & IN_BAND_FILTER;
	chain_sig_b = le32_to_cpu(rx_info->beacon_rssi_b) & IN_BAND_FILTER;
	chain_sig_c = le32_to_cpu(rx_info->beacon_rssi_c) & IN_BAND_FILTER;

	spin_unlock_irqrestore(&priv->lock, flags);

	data->beacon_count++;

	data->chain_noise_a = (chain_noise_a + data->chain_noise_a);
	data->chain_noise_b = (chain_noise_b + data->chain_noise_b);
	data->chain_noise_c = (chain_noise_c + data->chain_noise_c);

	data->chain_signal_a = (chain_sig_a + data->chain_signal_a);
	data->chain_signal_b = (chain_sig_b + data->chain_signal_b);
	data->chain_signal_c = (chain_sig_c + data->chain_signal_c);

	IWL_DEBUG_CALIB(priv, "chan=%d, band24=%d, beacon=%d\n",
			rxon_chnum, rxon_band24, data->beacon_count);
	IWL_DEBUG_CALIB(priv, "chain_sig: a %d b %d c %d\n",
			chain_sig_a, chain_sig_b, chain_sig_c);
	IWL_DEBUG_CALIB(priv, "chain_noise: a %d b %d c %d\n",
			chain_noise_a, chain_noise_b, chain_noise_c);

	/* If this is the "chain_noise_num_beacons", determine:
	 * 1)  Disconnected antennas (using signal strengths)
	 * 2)  Differential gain (using silence noise) to balance receivers */
	if (data->beacon_count != priv->cfg->chain_noise_num_beacons)
		return;

	/* Analyze signal for disconnected antenna */
	average_sig[0] =
		(data->chain_signal_a) / priv->cfg->chain_noise_num_beacons;
	average_sig[1] =
		(data->chain_signal_b) / priv->cfg->chain_noise_num_beacons;
	average_sig[2] =
		(data->chain_signal_c) / priv->cfg->chain_noise_num_beacons;

	if (average_sig[0] >= average_sig[1]) {
		max_average_sig = average_sig[0];
		max_average_sig_antenna_i = 0;
		active_chains = (1 << max_average_sig_antenna_i);
	} else {
		max_average_sig = average_sig[1];
		max_average_sig_antenna_i = 1;
		active_chains = (1 << max_average_sig_antenna_i);
	}

	if (average_sig[2] >= max_average_sig) {
		max_average_sig = average_sig[2];
		max_average_sig_antenna_i = 2;
		active_chains = (1 << max_average_sig_antenna_i);
	}

	IWL_DEBUG_CALIB(priv, "average_sig: a %d b %d c %d\n",
		     average_sig[0], average_sig[1], average_sig[2]);
	IWL_DEBUG_CALIB(priv, "max_average_sig = %d, antenna %d\n",
		     max_average_sig, max_average_sig_antenna_i);

	/* Compare signal strengths for all 3 receivers. */
	for (i = 0; i < NUM_RX_CHAINS; i++) {
		if (i != max_average_sig_antenna_i) {
			s32 rssi_delta = (max_average_sig - average_sig[i]);

			/* If signal is very weak, compared with
			 * strongest, mark it as disconnected. */
			if (rssi_delta > MAXIMUM_ALLOWED_PATHLOSS)
				data->disconn_array[i] = 1;
			else
				active_chains |= (1 << i);
			IWL_DEBUG_CALIB(priv, "i = %d  rssiDelta = %d  "
			     "disconn_array[i] = %d\n",
			     i, rssi_delta, data->disconn_array[i]);
		}
	}

	/*
	 * The above algorithm sometimes fails when the ucode
	 * reports 0 for all chains. It's not clear why that
	 * happens to start with, but it is then causing trouble
	 * because this can make us enable more chains than the
	 * hardware really has.
	 *
	 * To be safe, simply mask out any chains that we know
	 * are not on the device.
	 */
	active_chains &= priv->hw_params.valid_rx_ant;

	num_tx_chains = 0;
	for (i = 0; i < NUM_RX_CHAINS; i++) {
		/* loops on all the bits of
		 * priv->hw_setting.valid_tx_ant */
		u8 ant_msk = (1 << i);
		if (!(priv->hw_params.valid_tx_ant & ant_msk))
			continue;

		num_tx_chains++;
		if (data->disconn_array[i] == 0)
			/* there is a Tx antenna connected */
			break;
		if (num_tx_chains == priv->hw_params.tx_chains_num &&
		    data->disconn_array[i]) {
			/*
			 * If all chains are disconnected
			 * connect the first valid tx chain
			 */
			first_chain =
				find_first_chain(priv->cfg->valid_tx_ant);
			data->disconn_array[first_chain] = 0;
			active_chains |= BIT(first_chain);
			IWL_DEBUG_CALIB(priv, "All Tx chains are disconnected W/A - declare %d as connected\n",
					first_chain);
			break;
		}
	}

	/* Save for use within RXON, TX, SCAN commands, etc. */
	priv->chain_noise_data.active_chains = active_chains;
	IWL_DEBUG_CALIB(priv, "active_chains (bitwise) = 0x%x\n",
			active_chains);

	/* Analyze noise for rx balance */
	average_noise[0] =
		((data->chain_noise_a) / priv->cfg->chain_noise_num_beacons);
	average_noise[1] =
		((data->chain_noise_b) / priv->cfg->chain_noise_num_beacons);
	average_noise[2] =
		((data->chain_noise_c) / priv->cfg->chain_noise_num_beacons);

	for (i = 0; i < NUM_RX_CHAINS; i++) {
		if (!(data->disconn_array[i]) &&
		   (average_noise[i] <= min_average_noise)) {
			/* This means that chain i is active and has
			 * lower noise values so far: */
			min_average_noise = average_noise[i];
			min_average_noise_antenna_i = i;
		}
	}

	IWL_DEBUG_CALIB(priv, "average_noise: a %d b %d c %d\n",
			average_noise[0], average_noise[1],
			average_noise[2]);

	IWL_DEBUG_CALIB(priv, "min_average_noise = %d, antenna %d\n",
			min_average_noise, min_average_noise_antenna_i);

	if (priv->cfg->ops->utils->gain_computation)
		priv->cfg->ops->utils->gain_computation(priv, average_noise,
				min_average_noise_antenna_i, min_average_noise,
				find_first_chain(priv->cfg->valid_rx_ant));

	/* Some power changes may have been made during the calibration.
	 * Update and commit the RXON
	 */
	if (priv->cfg->ops->lib->update_chain_flags)
		priv->cfg->ops->lib->update_chain_flags(priv);

	data->state = IWL_CHAIN_NOISE_DONE;
	iwl_power_update_mode(priv, false);
}
EXPORT_SYMBOL(iwl_chain_noise_calibration);


void iwl_reset_run_time_calib(struct iwl_priv *priv)
{
	int i;
	memset(&(priv->sensitivity_data), 0,
	       sizeof(struct iwl_sensitivity_data));
	memset(&(priv->chain_noise_data), 0,
	       sizeof(struct iwl_chain_noise_data));
	for (i = 0; i < NUM_RX_CHAINS; i++)
		priv->chain_noise_data.delta_gain_code[i] =
				CHAIN_NOISE_DELTA_GAIN_INIT_VAL;

	/* Ask for statistics now, the uCode will send notification
	 * periodically after association */
	iwl_send_statistics_request(priv, CMD_ASYNC, true);
}
EXPORT_SYMBOL(iwl_reset_run_time_calib);