xref: /linux/drivers/net/wireless/intel/iwlwifi/dvm/calib.c (revision a4eb44a6435d6d8f9e642407a4a06f65eb90ca04)
1 // SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
2 /*
3  * Copyright (C) 2005-2014 Intel Corporation
4  */
5 #include <linux/slab.h>
6 #include <net/mac80211.h>
7 
8 #include "iwl-trans.h"
9 
10 #include "dev.h"
11 #include "calib.h"
12 #include "agn.h"
13 
14 /*****************************************************************************
15  * INIT calibrations framework
16  *****************************************************************************/
17 
18 /* Opaque calibration results */
19 struct iwl_calib_result {
20 	struct list_head list;
21 	size_t cmd_len;
22 	struct iwl_calib_hdr hdr;
23 	/* data follows */
24 };
25 
26 struct statistics_general_data {
27 	u32 beacon_silence_rssi_a;
28 	u32 beacon_silence_rssi_b;
29 	u32 beacon_silence_rssi_c;
30 	u32 beacon_energy_a;
31 	u32 beacon_energy_b;
32 	u32 beacon_energy_c;
33 };
34 
35 int iwl_send_calib_results(struct iwl_priv *priv)
36 {
37 	struct iwl_host_cmd hcmd = {
38 		.id = REPLY_PHY_CALIBRATION_CMD,
39 	};
40 	struct iwl_calib_result *res;
41 
42 	list_for_each_entry(res, &priv->calib_results, list) {
43 		int ret;
44 
45 		hcmd.len[0] = res->cmd_len;
46 		hcmd.data[0] = &res->hdr;
47 		hcmd.dataflags[0] = IWL_HCMD_DFL_NOCOPY;
48 		ret = iwl_dvm_send_cmd(priv, &hcmd);
49 		if (ret) {
50 			IWL_ERR(priv, "Error %d on calib cmd %d\n",
51 				ret, res->hdr.op_code);
52 			return ret;
53 		}
54 	}
55 
56 	return 0;
57 }
58 
59 int iwl_calib_set(struct iwl_priv *priv,
60 		  const struct iwl_calib_hdr *cmd, int len)
61 {
62 	struct iwl_calib_result *res, *tmp;
63 
64 	res = kmalloc(sizeof(*res) + len - sizeof(struct iwl_calib_hdr),
65 		      GFP_ATOMIC);
66 	if (!res)
67 		return -ENOMEM;
68 	memcpy(&res->hdr, cmd, len);
69 	res->cmd_len = len;
70 
71 	list_for_each_entry(tmp, &priv->calib_results, list) {
72 		if (tmp->hdr.op_code == res->hdr.op_code) {
73 			list_replace(&tmp->list, &res->list);
74 			kfree(tmp);
75 			return 0;
76 		}
77 	}
78 
79 	/* wasn't in list already */
80 	list_add_tail(&res->list, &priv->calib_results);
81 
82 	return 0;
83 }
84 
85 void iwl_calib_free_results(struct iwl_priv *priv)
86 {
87 	struct iwl_calib_result *res, *tmp;
88 
89 	list_for_each_entry_safe(res, tmp, &priv->calib_results, list) {
90 		list_del(&res->list);
91 		kfree(res);
92 	}
93 }
94 
95 /*****************************************************************************
96  * RUNTIME calibrations framework
97  *****************************************************************************/
98 
99 /* "false alarms" are signals that our DSP tries to lock onto,
100  *   but then determines that they are either noise, or transmissions
101  *   from a distant wireless network (also "noise", really) that get
102  *   "stepped on" by stronger transmissions within our own network.
103  * This algorithm attempts to set a sensitivity level that is high
104  *   enough to receive all of our own network traffic, but not so
105  *   high that our DSP gets too busy trying to lock onto non-network
106  *   activity/noise. */
107 static int iwl_sens_energy_cck(struct iwl_priv *priv,
108 				   u32 norm_fa,
109 				   u32 rx_enable_time,
110 				   struct statistics_general_data *rx_info)
111 {
112 	u32 max_nrg_cck = 0;
113 	int i = 0;
114 	u8 max_silence_rssi = 0;
115 	u32 silence_ref = 0;
116 	u8 silence_rssi_a = 0;
117 	u8 silence_rssi_b = 0;
118 	u8 silence_rssi_c = 0;
119 	u32 val;
120 
121 	/* "false_alarms" values below are cross-multiplications to assess the
122 	 *   numbers of false alarms within the measured period of actual Rx
123 	 *   (Rx is off when we're txing), vs the min/max expected false alarms
124 	 *   (some should be expected if rx is sensitive enough) in a
125 	 *   hypothetical listening period of 200 time units (TU), 204.8 msec:
126 	 *
127 	 * MIN_FA/fixed-time < false_alarms/actual-rx-time < MAX_FA/beacon-time
128 	 *
129 	 * */
130 	u32 false_alarms = norm_fa * 200 * 1024;
131 	u32 max_false_alarms = MAX_FA_CCK * rx_enable_time;
132 	u32 min_false_alarms = MIN_FA_CCK * rx_enable_time;
133 	struct iwl_sensitivity_data *data = NULL;
134 	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
135 
136 	data = &(priv->sensitivity_data);
137 
138 	data->nrg_auto_corr_silence_diff = 0;
139 
140 	/* Find max silence rssi among all 3 receivers.
141 	 * This is background noise, which may include transmissions from other
142 	 *    networks, measured during silence before our network's beacon */
143 	silence_rssi_a = (u8)((rx_info->beacon_silence_rssi_a &
144 			    ALL_BAND_FILTER) >> 8);
145 	silence_rssi_b = (u8)((rx_info->beacon_silence_rssi_b &
146 			    ALL_BAND_FILTER) >> 8);
147 	silence_rssi_c = (u8)((rx_info->beacon_silence_rssi_c &
148 			    ALL_BAND_FILTER) >> 8);
149 
150 	val = max(silence_rssi_b, silence_rssi_c);
151 	max_silence_rssi = max(silence_rssi_a, (u8) val);
152 
153 	/* Store silence rssi in 20-beacon history table */
154 	data->nrg_silence_rssi[data->nrg_silence_idx] = max_silence_rssi;
155 	data->nrg_silence_idx++;
156 	if (data->nrg_silence_idx >= NRG_NUM_PREV_STAT_L)
157 		data->nrg_silence_idx = 0;
158 
159 	/* Find max silence rssi across 20 beacon history */
160 	for (i = 0; i < NRG_NUM_PREV_STAT_L; i++) {
161 		val = data->nrg_silence_rssi[i];
162 		silence_ref = max(silence_ref, val);
163 	}
164 	IWL_DEBUG_CALIB(priv, "silence a %u, b %u, c %u, 20-bcn max %u\n",
165 			silence_rssi_a, silence_rssi_b, silence_rssi_c,
166 			silence_ref);
167 
168 	/* Find max rx energy (min value!) among all 3 receivers,
169 	 *   measured during beacon frame.
170 	 * Save it in 10-beacon history table. */
171 	i = data->nrg_energy_idx;
172 	val = min(rx_info->beacon_energy_b, rx_info->beacon_energy_c);
173 	data->nrg_value[i] = min(rx_info->beacon_energy_a, val);
174 
175 	data->nrg_energy_idx++;
176 	if (data->nrg_energy_idx >= 10)
177 		data->nrg_energy_idx = 0;
178 
179 	/* Find min rx energy (max value) across 10 beacon history.
180 	 * This is the minimum signal level that we want to receive well.
181 	 * Add backoff (margin so we don't miss slightly lower energy frames).
182 	 * This establishes an upper bound (min value) for energy threshold. */
183 	max_nrg_cck = data->nrg_value[0];
184 	for (i = 1; i < 10; i++)
185 		max_nrg_cck = (u32) max(max_nrg_cck, (data->nrg_value[i]));
186 	max_nrg_cck += 6;
187 
188 	IWL_DEBUG_CALIB(priv, "rx energy a %u, b %u, c %u, 10-bcn max/min %u\n",
189 			rx_info->beacon_energy_a, rx_info->beacon_energy_b,
190 			rx_info->beacon_energy_c, max_nrg_cck - 6);
191 
192 	/* Count number of consecutive beacons with fewer-than-desired
193 	 *   false alarms. */
194 	if (false_alarms < min_false_alarms)
195 		data->num_in_cck_no_fa++;
196 	else
197 		data->num_in_cck_no_fa = 0;
198 	IWL_DEBUG_CALIB(priv, "consecutive bcns with few false alarms = %u\n",
199 			data->num_in_cck_no_fa);
200 
201 	/* If we got too many false alarms this time, reduce sensitivity */
202 	if ((false_alarms > max_false_alarms) &&
203 		(data->auto_corr_cck > AUTO_CORR_MAX_TH_CCK)) {
204 		IWL_DEBUG_CALIB(priv, "norm FA %u > max FA %u\n",
205 		     false_alarms, max_false_alarms);
206 		IWL_DEBUG_CALIB(priv, "... reducing sensitivity\n");
207 		data->nrg_curr_state = IWL_FA_TOO_MANY;
208 		/* Store for "fewer than desired" on later beacon */
209 		data->nrg_silence_ref = silence_ref;
210 
211 		/* increase energy threshold (reduce nrg value)
212 		 *   to decrease sensitivity */
213 		data->nrg_th_cck = data->nrg_th_cck - NRG_STEP_CCK;
214 	/* Else if we got fewer than desired, increase sensitivity */
215 	} else if (false_alarms < min_false_alarms) {
216 		data->nrg_curr_state = IWL_FA_TOO_FEW;
217 
218 		/* Compare silence level with silence level for most recent
219 		 *   healthy number or too many false alarms */
220 		data->nrg_auto_corr_silence_diff = (s32)data->nrg_silence_ref -
221 						   (s32)silence_ref;
222 
223 		IWL_DEBUG_CALIB(priv, "norm FA %u < min FA %u, silence diff %d\n",
224 			 false_alarms, min_false_alarms,
225 			 data->nrg_auto_corr_silence_diff);
226 
227 		/* Increase value to increase sensitivity, but only if:
228 		 * 1a) previous beacon did *not* have *too many* false alarms
229 		 * 1b) AND there's a significant difference in Rx levels
230 		 *      from a previous beacon with too many, or healthy # FAs
231 		 * OR 2) We've seen a lot of beacons (100) with too few
232 		 *       false alarms */
233 		if ((data->nrg_prev_state != IWL_FA_TOO_MANY) &&
234 			((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
235 			(data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {
236 
237 			IWL_DEBUG_CALIB(priv, "... increasing sensitivity\n");
238 			/* Increase nrg value to increase sensitivity */
239 			val = data->nrg_th_cck + NRG_STEP_CCK;
240 			data->nrg_th_cck = min((u32)ranges->min_nrg_cck, val);
241 		} else {
242 			IWL_DEBUG_CALIB(priv, "... but not changing sensitivity\n");
243 		}
244 
245 	/* Else we got a healthy number of false alarms, keep status quo */
246 	} else {
247 		IWL_DEBUG_CALIB(priv, " FA in safe zone\n");
248 		data->nrg_curr_state = IWL_FA_GOOD_RANGE;
249 
250 		/* Store for use in "fewer than desired" with later beacon */
251 		data->nrg_silence_ref = silence_ref;
252 
253 		/* If previous beacon had too many false alarms,
254 		 *   give it some extra margin by reducing sensitivity again
255 		 *   (but don't go below measured energy of desired Rx) */
256 		if (data->nrg_prev_state == IWL_FA_TOO_MANY) {
257 			IWL_DEBUG_CALIB(priv, "... increasing margin\n");
258 			if (data->nrg_th_cck > (max_nrg_cck + NRG_MARGIN))
259 				data->nrg_th_cck -= NRG_MARGIN;
260 			else
261 				data->nrg_th_cck = max_nrg_cck;
262 		}
263 	}
264 
265 	/* Make sure the energy threshold does not go above the measured
266 	 * energy of the desired Rx signals (reduced by backoff margin),
267 	 * or else we might start missing Rx frames.
268 	 * Lower value is higher energy, so we use max()!
269 	 */
270 	data->nrg_th_cck = max(max_nrg_cck, data->nrg_th_cck);
271 	IWL_DEBUG_CALIB(priv, "new nrg_th_cck %u\n", data->nrg_th_cck);
272 
273 	data->nrg_prev_state = data->nrg_curr_state;
274 
275 	/* Auto-correlation CCK algorithm */
276 	if (false_alarms > min_false_alarms) {
277 
278 		/* increase auto_corr values to decrease sensitivity
279 		 * so the DSP won't be disturbed by the noise
280 		 */
281 		if (data->auto_corr_cck < AUTO_CORR_MAX_TH_CCK)
282 			data->auto_corr_cck = AUTO_CORR_MAX_TH_CCK + 1;
283 		else {
284 			val = data->auto_corr_cck + AUTO_CORR_STEP_CCK;
285 			data->auto_corr_cck =
286 				min((u32)ranges->auto_corr_max_cck, val);
287 		}
288 		val = data->auto_corr_cck_mrc + AUTO_CORR_STEP_CCK;
289 		data->auto_corr_cck_mrc =
290 			min((u32)ranges->auto_corr_max_cck_mrc, val);
291 	} else if ((false_alarms < min_false_alarms) &&
292 	   ((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
293 	   (data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {
294 
295 		/* Decrease auto_corr values to increase sensitivity */
296 		val = data->auto_corr_cck - AUTO_CORR_STEP_CCK;
297 		data->auto_corr_cck =
298 			max((u32)ranges->auto_corr_min_cck, val);
299 		val = data->auto_corr_cck_mrc - AUTO_CORR_STEP_CCK;
300 		data->auto_corr_cck_mrc =
301 			max((u32)ranges->auto_corr_min_cck_mrc, val);
302 	}
303 
304 	return 0;
305 }
306 
307 
308 static int iwl_sens_auto_corr_ofdm(struct iwl_priv *priv,
309 				       u32 norm_fa,
310 				       u32 rx_enable_time)
311 {
312 	u32 val;
313 	u32 false_alarms = norm_fa * 200 * 1024;
314 	u32 max_false_alarms = MAX_FA_OFDM * rx_enable_time;
315 	u32 min_false_alarms = MIN_FA_OFDM * rx_enable_time;
316 	struct iwl_sensitivity_data *data = NULL;
317 	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
318 
319 	data = &(priv->sensitivity_data);
320 
321 	/* If we got too many false alarms this time, reduce sensitivity */
322 	if (false_alarms > max_false_alarms) {
323 
324 		IWL_DEBUG_CALIB(priv, "norm FA %u > max FA %u)\n",
325 			     false_alarms, max_false_alarms);
326 
327 		val = data->auto_corr_ofdm + AUTO_CORR_STEP_OFDM;
328 		data->auto_corr_ofdm =
329 			min((u32)ranges->auto_corr_max_ofdm, val);
330 
331 		val = data->auto_corr_ofdm_mrc + AUTO_CORR_STEP_OFDM;
332 		data->auto_corr_ofdm_mrc =
333 			min((u32)ranges->auto_corr_max_ofdm_mrc, val);
334 
335 		val = data->auto_corr_ofdm_x1 + AUTO_CORR_STEP_OFDM;
336 		data->auto_corr_ofdm_x1 =
337 			min((u32)ranges->auto_corr_max_ofdm_x1, val);
338 
339 		val = data->auto_corr_ofdm_mrc_x1 + AUTO_CORR_STEP_OFDM;
340 		data->auto_corr_ofdm_mrc_x1 =
341 			min((u32)ranges->auto_corr_max_ofdm_mrc_x1, val);
342 	}
343 
344 	/* Else if we got fewer than desired, increase sensitivity */
345 	else if (false_alarms < min_false_alarms) {
346 
347 		IWL_DEBUG_CALIB(priv, "norm FA %u < min FA %u\n",
348 			     false_alarms, min_false_alarms);
349 
350 		val = data->auto_corr_ofdm - AUTO_CORR_STEP_OFDM;
351 		data->auto_corr_ofdm =
352 			max((u32)ranges->auto_corr_min_ofdm, val);
353 
354 		val = data->auto_corr_ofdm_mrc - AUTO_CORR_STEP_OFDM;
355 		data->auto_corr_ofdm_mrc =
356 			max((u32)ranges->auto_corr_min_ofdm_mrc, val);
357 
358 		val = data->auto_corr_ofdm_x1 - AUTO_CORR_STEP_OFDM;
359 		data->auto_corr_ofdm_x1 =
360 			max((u32)ranges->auto_corr_min_ofdm_x1, val);
361 
362 		val = data->auto_corr_ofdm_mrc_x1 - AUTO_CORR_STEP_OFDM;
363 		data->auto_corr_ofdm_mrc_x1 =
364 			max((u32)ranges->auto_corr_min_ofdm_mrc_x1, val);
365 	} else {
366 		IWL_DEBUG_CALIB(priv, "min FA %u < norm FA %u < max FA %u OK\n",
367 			 min_false_alarms, false_alarms, max_false_alarms);
368 	}
369 	return 0;
370 }
371 
372 static void iwl_prepare_legacy_sensitivity_tbl(struct iwl_priv *priv,
373 				struct iwl_sensitivity_data *data,
374 				__le16 *tbl)
375 {
376 	tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_INDEX] =
377 				cpu_to_le16((u16)data->auto_corr_ofdm);
378 	tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_MRC_INDEX] =
379 				cpu_to_le16((u16)data->auto_corr_ofdm_mrc);
380 	tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_INDEX] =
381 				cpu_to_le16((u16)data->auto_corr_ofdm_x1);
382 	tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_MRC_INDEX] =
383 				cpu_to_le16((u16)data->auto_corr_ofdm_mrc_x1);
384 
385 	tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_INDEX] =
386 				cpu_to_le16((u16)data->auto_corr_cck);
387 	tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_MRC_INDEX] =
388 				cpu_to_le16((u16)data->auto_corr_cck_mrc);
389 
390 	tbl[HD_MIN_ENERGY_CCK_DET_INDEX] =
391 				cpu_to_le16((u16)data->nrg_th_cck);
392 	tbl[HD_MIN_ENERGY_OFDM_DET_INDEX] =
393 				cpu_to_le16((u16)data->nrg_th_ofdm);
394 
395 	tbl[HD_BARKER_CORR_TH_ADD_MIN_INDEX] =
396 				cpu_to_le16(data->barker_corr_th_min);
397 	tbl[HD_BARKER_CORR_TH_ADD_MIN_MRC_INDEX] =
398 				cpu_to_le16(data->barker_corr_th_min_mrc);
399 	tbl[HD_OFDM_ENERGY_TH_IN_INDEX] =
400 				cpu_to_le16(data->nrg_th_cca);
401 
402 	IWL_DEBUG_CALIB(priv, "ofdm: ac %u mrc %u x1 %u mrc_x1 %u thresh %u\n",
403 			data->auto_corr_ofdm, data->auto_corr_ofdm_mrc,
404 			data->auto_corr_ofdm_x1, data->auto_corr_ofdm_mrc_x1,
405 			data->nrg_th_ofdm);
406 
407 	IWL_DEBUG_CALIB(priv, "cck: ac %u mrc %u thresh %u\n",
408 			data->auto_corr_cck, data->auto_corr_cck_mrc,
409 			data->nrg_th_cck);
410 }
411 
412 /* Prepare a SENSITIVITY_CMD, send to uCode if values have changed */
413 static int iwl_sensitivity_write(struct iwl_priv *priv)
414 {
415 	struct iwl_sensitivity_cmd cmd;
416 	struct iwl_sensitivity_data *data = NULL;
417 	struct iwl_host_cmd cmd_out = {
418 		.id = SENSITIVITY_CMD,
419 		.len = { sizeof(struct iwl_sensitivity_cmd), },
420 		.flags = CMD_ASYNC,
421 		.data = { &cmd, },
422 	};
423 
424 	data = &(priv->sensitivity_data);
425 
426 	memset(&cmd, 0, sizeof(cmd));
427 
428 	iwl_prepare_legacy_sensitivity_tbl(priv, data, &cmd.table[0]);
429 
430 	/* Update uCode's "work" table, and copy it to DSP */
431 	cmd.control = SENSITIVITY_CMD_CONTROL_WORK_TABLE;
432 
433 	/* Don't send command to uCode if nothing has changed */
434 	if (!memcmp(&cmd.table[0], &(priv->sensitivity_tbl[0]),
435 		    sizeof(u16)*HD_TABLE_SIZE)) {
436 		IWL_DEBUG_CALIB(priv, "No change in SENSITIVITY_CMD\n");
437 		return 0;
438 	}
439 
440 	/* Copy table for comparison next time */
441 	memcpy(&(priv->sensitivity_tbl[0]), &(cmd.table[0]),
442 	       sizeof(u16)*HD_TABLE_SIZE);
443 
444 	return iwl_dvm_send_cmd(priv, &cmd_out);
445 }
446 
447 /* Prepare a SENSITIVITY_CMD, send to uCode if values have changed */
448 static int iwl_enhance_sensitivity_write(struct iwl_priv *priv)
449 {
450 	struct iwl_enhance_sensitivity_cmd cmd;
451 	struct iwl_sensitivity_data *data = NULL;
452 	struct iwl_host_cmd cmd_out = {
453 		.id = SENSITIVITY_CMD,
454 		.len = { sizeof(struct iwl_enhance_sensitivity_cmd), },
455 		.flags = CMD_ASYNC,
456 		.data = { &cmd, },
457 	};
458 
459 	data = &(priv->sensitivity_data);
460 
461 	memset(&cmd, 0, sizeof(cmd));
462 
463 	iwl_prepare_legacy_sensitivity_tbl(priv, data, &cmd.enhance_table[0]);
464 
465 	if (priv->lib->hd_v2) {
466 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX] =
467 			HD_INA_NON_SQUARE_DET_OFDM_DATA_V2;
468 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_CCK_INDEX] =
469 			HD_INA_NON_SQUARE_DET_CCK_DATA_V2;
470 		cmd.enhance_table[HD_CORR_11_INSTEAD_OF_CORR_9_EN_INDEX] =
471 			HD_CORR_11_INSTEAD_OF_CORR_9_EN_DATA_V2;
472 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
473 			HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_DATA_V2;
474 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
475 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V2;
476 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_INDEX] =
477 			HD_OFDM_NON_SQUARE_DET_SLOPE_DATA_V2;
478 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_INDEX] =
479 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_DATA_V2;
480 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
481 			HD_CCK_NON_SQUARE_DET_SLOPE_MRC_DATA_V2;
482 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
483 			HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V2;
484 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_INDEX] =
485 			HD_CCK_NON_SQUARE_DET_SLOPE_DATA_V2;
486 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_INDEX] =
487 			HD_CCK_NON_SQUARE_DET_INTERCEPT_DATA_V2;
488 	} else {
489 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX] =
490 			HD_INA_NON_SQUARE_DET_OFDM_DATA_V1;
491 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_CCK_INDEX] =
492 			HD_INA_NON_SQUARE_DET_CCK_DATA_V1;
493 		cmd.enhance_table[HD_CORR_11_INSTEAD_OF_CORR_9_EN_INDEX] =
494 			HD_CORR_11_INSTEAD_OF_CORR_9_EN_DATA_V1;
495 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
496 			HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_DATA_V1;
497 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
498 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V1;
499 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_INDEX] =
500 			HD_OFDM_NON_SQUARE_DET_SLOPE_DATA_V1;
501 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_INDEX] =
502 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_DATA_V1;
503 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
504 			HD_CCK_NON_SQUARE_DET_SLOPE_MRC_DATA_V1;
505 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
506 			HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V1;
507 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_INDEX] =
508 			HD_CCK_NON_SQUARE_DET_SLOPE_DATA_V1;
509 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_INDEX] =
510 			HD_CCK_NON_SQUARE_DET_INTERCEPT_DATA_V1;
511 	}
512 
513 	/* Update uCode's "work" table, and copy it to DSP */
514 	cmd.control = SENSITIVITY_CMD_CONTROL_WORK_TABLE;
515 
516 	/* Don't send command to uCode if nothing has changed */
517 	if (!memcmp(&cmd.enhance_table[0], &(priv->sensitivity_tbl[0]),
518 		    sizeof(u16)*HD_TABLE_SIZE) &&
519 	    !memcmp(&cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX],
520 		    &(priv->enhance_sensitivity_tbl[0]),
521 		    sizeof(u16)*ENHANCE_HD_TABLE_ENTRIES)) {
522 		IWL_DEBUG_CALIB(priv, "No change in SENSITIVITY_CMD\n");
523 		return 0;
524 	}
525 
526 	/* Copy table for comparison next time */
527 	memcpy(&(priv->sensitivity_tbl[0]), &(cmd.enhance_table[0]),
528 	       sizeof(u16)*HD_TABLE_SIZE);
529 	memcpy(&(priv->enhance_sensitivity_tbl[0]),
530 	       &(cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX]),
531 	       sizeof(u16)*ENHANCE_HD_TABLE_ENTRIES);
532 
533 	return iwl_dvm_send_cmd(priv, &cmd_out);
534 }
535 
536 void iwl_init_sensitivity(struct iwl_priv *priv)
537 {
538 	int ret = 0;
539 	int i;
540 	struct iwl_sensitivity_data *data = NULL;
541 	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
542 
543 	if (priv->calib_disabled & IWL_SENSITIVITY_CALIB_DISABLED)
544 		return;
545 
546 	IWL_DEBUG_CALIB(priv, "Start iwl_init_sensitivity\n");
547 
548 	/* Clear driver's sensitivity algo data */
549 	data = &(priv->sensitivity_data);
550 
551 	if (ranges == NULL)
552 		return;
553 
554 	memset(data, 0, sizeof(struct iwl_sensitivity_data));
555 
556 	data->num_in_cck_no_fa = 0;
557 	data->nrg_curr_state = IWL_FA_TOO_MANY;
558 	data->nrg_prev_state = IWL_FA_TOO_MANY;
559 	data->nrg_silence_ref = 0;
560 	data->nrg_silence_idx = 0;
561 	data->nrg_energy_idx = 0;
562 
563 	for (i = 0; i < 10; i++)
564 		data->nrg_value[i] = 0;
565 
566 	for (i = 0; i < NRG_NUM_PREV_STAT_L; i++)
567 		data->nrg_silence_rssi[i] = 0;
568 
569 	data->auto_corr_ofdm =  ranges->auto_corr_min_ofdm;
570 	data->auto_corr_ofdm_mrc = ranges->auto_corr_min_ofdm_mrc;
571 	data->auto_corr_ofdm_x1  = ranges->auto_corr_min_ofdm_x1;
572 	data->auto_corr_ofdm_mrc_x1 = ranges->auto_corr_min_ofdm_mrc_x1;
573 	data->auto_corr_cck = AUTO_CORR_CCK_MIN_VAL_DEF;
574 	data->auto_corr_cck_mrc = ranges->auto_corr_min_cck_mrc;
575 	data->nrg_th_cck = ranges->nrg_th_cck;
576 	data->nrg_th_ofdm = ranges->nrg_th_ofdm;
577 	data->barker_corr_th_min = ranges->barker_corr_th_min;
578 	data->barker_corr_th_min_mrc = ranges->barker_corr_th_min_mrc;
579 	data->nrg_th_cca = ranges->nrg_th_cca;
580 
581 	data->last_bad_plcp_cnt_ofdm = 0;
582 	data->last_fa_cnt_ofdm = 0;
583 	data->last_bad_plcp_cnt_cck = 0;
584 	data->last_fa_cnt_cck = 0;
585 
586 	if (priv->fw->enhance_sensitivity_table)
587 		ret |= iwl_enhance_sensitivity_write(priv);
588 	else
589 		ret |= iwl_sensitivity_write(priv);
590 	IWL_DEBUG_CALIB(priv, "<<return 0x%X\n", ret);
591 }
592 
593 void iwl_sensitivity_calibration(struct iwl_priv *priv)
594 {
595 	u32 rx_enable_time;
596 	u32 fa_cck;
597 	u32 fa_ofdm;
598 	u32 bad_plcp_cck;
599 	u32 bad_plcp_ofdm;
600 	u32 norm_fa_ofdm;
601 	u32 norm_fa_cck;
602 	struct iwl_sensitivity_data *data = NULL;
603 	struct statistics_rx_non_phy *rx_info;
604 	struct statistics_rx_phy *ofdm, *cck;
605 	struct statistics_general_data statis;
606 
607 	if (priv->calib_disabled & IWL_SENSITIVITY_CALIB_DISABLED)
608 		return;
609 
610 	data = &(priv->sensitivity_data);
611 
612 	if (!iwl_is_any_associated(priv)) {
613 		IWL_DEBUG_CALIB(priv, "<< - not associated\n");
614 		return;
615 	}
616 
617 	spin_lock_bh(&priv->statistics.lock);
618 	rx_info = &priv->statistics.rx_non_phy;
619 	ofdm = &priv->statistics.rx_ofdm;
620 	cck = &priv->statistics.rx_cck;
621 	if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
622 		IWL_DEBUG_CALIB(priv, "<< invalid data.\n");
623 		spin_unlock_bh(&priv->statistics.lock);
624 		return;
625 	}
626 
627 	/* Extract Statistics: */
628 	rx_enable_time = le32_to_cpu(rx_info->channel_load);
629 	fa_cck = le32_to_cpu(cck->false_alarm_cnt);
630 	fa_ofdm = le32_to_cpu(ofdm->false_alarm_cnt);
631 	bad_plcp_cck = le32_to_cpu(cck->plcp_err);
632 	bad_plcp_ofdm = le32_to_cpu(ofdm->plcp_err);
633 
634 	statis.beacon_silence_rssi_a =
635 			le32_to_cpu(rx_info->beacon_silence_rssi_a);
636 	statis.beacon_silence_rssi_b =
637 			le32_to_cpu(rx_info->beacon_silence_rssi_b);
638 	statis.beacon_silence_rssi_c =
639 			le32_to_cpu(rx_info->beacon_silence_rssi_c);
640 	statis.beacon_energy_a =
641 			le32_to_cpu(rx_info->beacon_energy_a);
642 	statis.beacon_energy_b =
643 			le32_to_cpu(rx_info->beacon_energy_b);
644 	statis.beacon_energy_c =
645 			le32_to_cpu(rx_info->beacon_energy_c);
646 
647 	spin_unlock_bh(&priv->statistics.lock);
648 
649 	IWL_DEBUG_CALIB(priv, "rx_enable_time = %u usecs\n", rx_enable_time);
650 
651 	if (!rx_enable_time) {
652 		IWL_DEBUG_CALIB(priv, "<< RX Enable Time == 0!\n");
653 		return;
654 	}
655 
656 	/* These statistics increase monotonically, and do not reset
657 	 *   at each beacon.  Calculate difference from last value, or just
658 	 *   use the new statistics value if it has reset or wrapped around. */
659 	if (data->last_bad_plcp_cnt_cck > bad_plcp_cck)
660 		data->last_bad_plcp_cnt_cck = bad_plcp_cck;
661 	else {
662 		bad_plcp_cck -= data->last_bad_plcp_cnt_cck;
663 		data->last_bad_plcp_cnt_cck += bad_plcp_cck;
664 	}
665 
666 	if (data->last_bad_plcp_cnt_ofdm > bad_plcp_ofdm)
667 		data->last_bad_plcp_cnt_ofdm = bad_plcp_ofdm;
668 	else {
669 		bad_plcp_ofdm -= data->last_bad_plcp_cnt_ofdm;
670 		data->last_bad_plcp_cnt_ofdm += bad_plcp_ofdm;
671 	}
672 
673 	if (data->last_fa_cnt_ofdm > fa_ofdm)
674 		data->last_fa_cnt_ofdm = fa_ofdm;
675 	else {
676 		fa_ofdm -= data->last_fa_cnt_ofdm;
677 		data->last_fa_cnt_ofdm += fa_ofdm;
678 	}
679 
680 	if (data->last_fa_cnt_cck > fa_cck)
681 		data->last_fa_cnt_cck = fa_cck;
682 	else {
683 		fa_cck -= data->last_fa_cnt_cck;
684 		data->last_fa_cnt_cck += fa_cck;
685 	}
686 
687 	/* Total aborted signal locks */
688 	norm_fa_ofdm = fa_ofdm + bad_plcp_ofdm;
689 	norm_fa_cck = fa_cck + bad_plcp_cck;
690 
691 	IWL_DEBUG_CALIB(priv, "cck: fa %u badp %u  ofdm: fa %u badp %u\n", fa_cck,
692 			bad_plcp_cck, fa_ofdm, bad_plcp_ofdm);
693 
694 	iwl_sens_auto_corr_ofdm(priv, norm_fa_ofdm, rx_enable_time);
695 	iwl_sens_energy_cck(priv, norm_fa_cck, rx_enable_time, &statis);
696 	if (priv->fw->enhance_sensitivity_table)
697 		iwl_enhance_sensitivity_write(priv);
698 	else
699 		iwl_sensitivity_write(priv);
700 }
701 
702 static inline u8 find_first_chain(u8 mask)
703 {
704 	if (mask & ANT_A)
705 		return CHAIN_A;
706 	if (mask & ANT_B)
707 		return CHAIN_B;
708 	return CHAIN_C;
709 }
710 
711 /*
712  * Run disconnected antenna algorithm to find out which antennas are
713  * disconnected.
714  */
715 static void iwl_find_disconn_antenna(struct iwl_priv *priv, u32* average_sig,
716 				     struct iwl_chain_noise_data *data)
717 {
718 	u32 active_chains = 0;
719 	u32 max_average_sig;
720 	u16 max_average_sig_antenna_i;
721 	u8 num_tx_chains;
722 	u8 first_chain;
723 	u16 i = 0;
724 
725 	average_sig[0] = data->chain_signal_a / IWL_CAL_NUM_BEACONS;
726 	average_sig[1] = data->chain_signal_b / IWL_CAL_NUM_BEACONS;
727 	average_sig[2] = data->chain_signal_c / IWL_CAL_NUM_BEACONS;
728 
729 	if (average_sig[0] >= average_sig[1]) {
730 		max_average_sig = average_sig[0];
731 		max_average_sig_antenna_i = 0;
732 		active_chains = (1 << max_average_sig_antenna_i);
733 	} else {
734 		max_average_sig = average_sig[1];
735 		max_average_sig_antenna_i = 1;
736 		active_chains = (1 << max_average_sig_antenna_i);
737 	}
738 
739 	if (average_sig[2] >= max_average_sig) {
740 		max_average_sig = average_sig[2];
741 		max_average_sig_antenna_i = 2;
742 		active_chains = (1 << max_average_sig_antenna_i);
743 	}
744 
745 	IWL_DEBUG_CALIB(priv, "average_sig: a %d b %d c %d\n",
746 		     average_sig[0], average_sig[1], average_sig[2]);
747 	IWL_DEBUG_CALIB(priv, "max_average_sig = %d, antenna %d\n",
748 		     max_average_sig, max_average_sig_antenna_i);
749 
750 	/* Compare signal strengths for all 3 receivers. */
751 	for (i = 0; i < NUM_RX_CHAINS; i++) {
752 		if (i != max_average_sig_antenna_i) {
753 			s32 rssi_delta = (max_average_sig - average_sig[i]);
754 
755 			/* If signal is very weak, compared with
756 			 * strongest, mark it as disconnected. */
757 			if (rssi_delta > MAXIMUM_ALLOWED_PATHLOSS)
758 				data->disconn_array[i] = 1;
759 			else
760 				active_chains |= (1 << i);
761 			IWL_DEBUG_CALIB(priv, "i = %d  rssiDelta = %d  "
762 			     "disconn_array[i] = %d\n",
763 			     i, rssi_delta, data->disconn_array[i]);
764 		}
765 	}
766 
767 	/*
768 	 * The above algorithm sometimes fails when the ucode
769 	 * reports 0 for all chains. It's not clear why that
770 	 * happens to start with, but it is then causing trouble
771 	 * because this can make us enable more chains than the
772 	 * hardware really has.
773 	 *
774 	 * To be safe, simply mask out any chains that we know
775 	 * are not on the device.
776 	 */
777 	active_chains &= priv->nvm_data->valid_rx_ant;
778 
779 	num_tx_chains = 0;
780 	for (i = 0; i < NUM_RX_CHAINS; i++) {
781 		/* loops on all the bits of
782 		 * priv->hw_setting.valid_tx_ant */
783 		u8 ant_msk = (1 << i);
784 		if (!(priv->nvm_data->valid_tx_ant & ant_msk))
785 			continue;
786 
787 		num_tx_chains++;
788 		if (data->disconn_array[i] == 0)
789 			/* there is a Tx antenna connected */
790 			break;
791 		if (num_tx_chains == priv->hw_params.tx_chains_num &&
792 		    data->disconn_array[i]) {
793 			/*
794 			 * If all chains are disconnected
795 			 * connect the first valid tx chain
796 			 */
797 			first_chain =
798 				find_first_chain(priv->nvm_data->valid_tx_ant);
799 			data->disconn_array[first_chain] = 0;
800 			active_chains |= BIT(first_chain);
801 			IWL_DEBUG_CALIB(priv,
802 					"All Tx chains are disconnected W/A - declare %d as connected\n",
803 					first_chain);
804 			break;
805 		}
806 	}
807 
808 	if (active_chains != priv->nvm_data->valid_rx_ant &&
809 	    active_chains != priv->chain_noise_data.active_chains)
810 		IWL_DEBUG_CALIB(priv,
811 				"Detected that not all antennas are connected! "
812 				"Connected: %#x, valid: %#x.\n",
813 				active_chains,
814 				priv->nvm_data->valid_rx_ant);
815 
816 	/* Save for use within RXON, TX, SCAN commands, etc. */
817 	data->active_chains = active_chains;
818 	IWL_DEBUG_CALIB(priv, "active_chains (bitwise) = 0x%x\n",
819 			active_chains);
820 }
821 
822 static void iwlagn_gain_computation(struct iwl_priv *priv,
823 				    u32 average_noise[NUM_RX_CHAINS],
824 				    u8 default_chain)
825 {
826 	int i;
827 	s32 delta_g;
828 	struct iwl_chain_noise_data *data = &priv->chain_noise_data;
829 
830 	/*
831 	 * Find Gain Code for the chains based on "default chain"
832 	 */
833 	for (i = default_chain + 1; i < NUM_RX_CHAINS; i++) {
834 		if ((data->disconn_array[i])) {
835 			data->delta_gain_code[i] = 0;
836 			continue;
837 		}
838 
839 		delta_g = (priv->lib->chain_noise_scale *
840 			((s32)average_noise[default_chain] -
841 			(s32)average_noise[i])) / 1500;
842 
843 		/* bound gain by 2 bits value max, 3rd bit is sign */
844 		data->delta_gain_code[i] =
845 			min(abs(delta_g), CHAIN_NOISE_MAX_DELTA_GAIN_CODE);
846 
847 		if (delta_g < 0)
848 			/*
849 			 * set negative sign ...
850 			 * note to Intel developers:  This is uCode API format,
851 			 *   not the format of any internal device registers.
852 			 *   Do not change this format for e.g. 6050 or similar
853 			 *   devices.  Change format only if more resolution
854 			 *   (i.e. more than 2 bits magnitude) is needed.
855 			 */
856 			data->delta_gain_code[i] |= (1 << 2);
857 	}
858 
859 	IWL_DEBUG_CALIB(priv, "Delta gains: ANT_B = %d  ANT_C = %d\n",
860 			data->delta_gain_code[1], data->delta_gain_code[2]);
861 
862 	if (!data->radio_write) {
863 		struct iwl_calib_chain_noise_gain_cmd cmd;
864 
865 		memset(&cmd, 0, sizeof(cmd));
866 
867 		iwl_set_calib_hdr(&cmd.hdr,
868 			priv->phy_calib_chain_noise_gain_cmd);
869 		cmd.delta_gain_1 = data->delta_gain_code[1];
870 		cmd.delta_gain_2 = data->delta_gain_code[2];
871 		iwl_dvm_send_cmd_pdu(priv, REPLY_PHY_CALIBRATION_CMD,
872 			CMD_ASYNC, sizeof(cmd), &cmd);
873 
874 		data->radio_write = 1;
875 		data->state = IWL_CHAIN_NOISE_CALIBRATED;
876 	}
877 }
878 
879 /*
880  * Accumulate 16 beacons of signal and noise statistics for each of
881  *   3 receivers/antennas/rx-chains, then figure out:
882  * 1)  Which antennas are connected.
883  * 2)  Differential rx gain settings to balance the 3 receivers.
884  */
885 void iwl_chain_noise_calibration(struct iwl_priv *priv)
886 {
887 	struct iwl_chain_noise_data *data = NULL;
888 
889 	u32 chain_noise_a;
890 	u32 chain_noise_b;
891 	u32 chain_noise_c;
892 	u32 chain_sig_a;
893 	u32 chain_sig_b;
894 	u32 chain_sig_c;
895 	u32 average_sig[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
896 	u32 average_noise[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
897 	u32 min_average_noise = MIN_AVERAGE_NOISE_MAX_VALUE;
898 	u16 min_average_noise_antenna_i = INITIALIZATION_VALUE;
899 	u16 i = 0;
900 	u16 rxon_chnum = INITIALIZATION_VALUE;
901 	u16 stat_chnum = INITIALIZATION_VALUE;
902 	u8 rxon_band24;
903 	u8 stat_band24;
904 	struct statistics_rx_non_phy *rx_info;
905 
906 	/*
907 	 * MULTI-FIXME:
908 	 * When we support multiple interfaces on different channels,
909 	 * this must be modified/fixed.
910 	 */
911 	struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
912 
913 	if (priv->calib_disabled & IWL_CHAIN_NOISE_CALIB_DISABLED)
914 		return;
915 
916 	data = &(priv->chain_noise_data);
917 
918 	/*
919 	 * Accumulate just the first "chain_noise_num_beacons" after
920 	 * the first association, then we're done forever.
921 	 */
922 	if (data->state != IWL_CHAIN_NOISE_ACCUMULATE) {
923 		if (data->state == IWL_CHAIN_NOISE_ALIVE)
924 			IWL_DEBUG_CALIB(priv, "Wait for noise calib reset\n");
925 		return;
926 	}
927 
928 	spin_lock_bh(&priv->statistics.lock);
929 
930 	rx_info = &priv->statistics.rx_non_phy;
931 
932 	if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
933 		IWL_DEBUG_CALIB(priv, " << Interference data unavailable\n");
934 		spin_unlock_bh(&priv->statistics.lock);
935 		return;
936 	}
937 
938 	rxon_band24 = !!(ctx->staging.flags & RXON_FLG_BAND_24G_MSK);
939 	rxon_chnum = le16_to_cpu(ctx->staging.channel);
940 	stat_band24 =
941 		!!(priv->statistics.flag & STATISTICS_REPLY_FLG_BAND_24G_MSK);
942 	stat_chnum = le32_to_cpu(priv->statistics.flag) >> 16;
943 
944 	/* Make sure we accumulate data for just the associated channel
945 	 *   (even if scanning). */
946 	if ((rxon_chnum != stat_chnum) || (rxon_band24 != stat_band24)) {
947 		IWL_DEBUG_CALIB(priv, "Stats not from chan=%d, band24=%d\n",
948 				rxon_chnum, rxon_band24);
949 		spin_unlock_bh(&priv->statistics.lock);
950 		return;
951 	}
952 
953 	/*
954 	 *  Accumulate beacon statistics values across
955 	 * "chain_noise_num_beacons"
956 	 */
957 	chain_noise_a = le32_to_cpu(rx_info->beacon_silence_rssi_a) &
958 				IN_BAND_FILTER;
959 	chain_noise_b = le32_to_cpu(rx_info->beacon_silence_rssi_b) &
960 				IN_BAND_FILTER;
961 	chain_noise_c = le32_to_cpu(rx_info->beacon_silence_rssi_c) &
962 				IN_BAND_FILTER;
963 
964 	chain_sig_a = le32_to_cpu(rx_info->beacon_rssi_a) & IN_BAND_FILTER;
965 	chain_sig_b = le32_to_cpu(rx_info->beacon_rssi_b) & IN_BAND_FILTER;
966 	chain_sig_c = le32_to_cpu(rx_info->beacon_rssi_c) & IN_BAND_FILTER;
967 
968 	spin_unlock_bh(&priv->statistics.lock);
969 
970 	data->beacon_count++;
971 
972 	data->chain_noise_a = (chain_noise_a + data->chain_noise_a);
973 	data->chain_noise_b = (chain_noise_b + data->chain_noise_b);
974 	data->chain_noise_c = (chain_noise_c + data->chain_noise_c);
975 
976 	data->chain_signal_a = (chain_sig_a + data->chain_signal_a);
977 	data->chain_signal_b = (chain_sig_b + data->chain_signal_b);
978 	data->chain_signal_c = (chain_sig_c + data->chain_signal_c);
979 
980 	IWL_DEBUG_CALIB(priv, "chan=%d, band24=%d, beacon=%d\n",
981 			rxon_chnum, rxon_band24, data->beacon_count);
982 	IWL_DEBUG_CALIB(priv, "chain_sig: a %d b %d c %d\n",
983 			chain_sig_a, chain_sig_b, chain_sig_c);
984 	IWL_DEBUG_CALIB(priv, "chain_noise: a %d b %d c %d\n",
985 			chain_noise_a, chain_noise_b, chain_noise_c);
986 
987 	/* If this is the "chain_noise_num_beacons", determine:
988 	 * 1)  Disconnected antennas (using signal strengths)
989 	 * 2)  Differential gain (using silence noise) to balance receivers */
990 	if (data->beacon_count != IWL_CAL_NUM_BEACONS)
991 		return;
992 
993 	/* Analyze signal for disconnected antenna */
994 	if (priv->lib->bt_params &&
995 	    priv->lib->bt_params->advanced_bt_coexist) {
996 		/* Disable disconnected antenna algorithm for advanced
997 		   bt coex, assuming valid antennas are connected */
998 		data->active_chains = priv->nvm_data->valid_rx_ant;
999 		for (i = 0; i < NUM_RX_CHAINS; i++)
1000 			if (!(data->active_chains & (1<<i)))
1001 				data->disconn_array[i] = 1;
1002 	} else
1003 		iwl_find_disconn_antenna(priv, average_sig, data);
1004 
1005 	/* Analyze noise for rx balance */
1006 	average_noise[0] = data->chain_noise_a / IWL_CAL_NUM_BEACONS;
1007 	average_noise[1] = data->chain_noise_b / IWL_CAL_NUM_BEACONS;
1008 	average_noise[2] = data->chain_noise_c / IWL_CAL_NUM_BEACONS;
1009 
1010 	for (i = 0; i < NUM_RX_CHAINS; i++) {
1011 		if (!(data->disconn_array[i]) &&
1012 		   (average_noise[i] <= min_average_noise)) {
1013 			/* This means that chain i is active and has
1014 			 * lower noise values so far: */
1015 			min_average_noise = average_noise[i];
1016 			min_average_noise_antenna_i = i;
1017 		}
1018 	}
1019 
1020 	IWL_DEBUG_CALIB(priv, "average_noise: a %d b %d c %d\n",
1021 			average_noise[0], average_noise[1],
1022 			average_noise[2]);
1023 
1024 	IWL_DEBUG_CALIB(priv, "min_average_noise = %d, antenna %d\n",
1025 			min_average_noise, min_average_noise_antenna_i);
1026 
1027 	iwlagn_gain_computation(
1028 		priv, average_noise,
1029 		find_first_chain(priv->nvm_data->valid_rx_ant));
1030 
1031 	/* Some power changes may have been made during the calibration.
1032 	 * Update and commit the RXON
1033 	 */
1034 	iwl_update_chain_flags(priv);
1035 
1036 	data->state = IWL_CHAIN_NOISE_DONE;
1037 	iwl_power_update_mode(priv, false);
1038 }
1039 
1040 void iwl_reset_run_time_calib(struct iwl_priv *priv)
1041 {
1042 	int i;
1043 	memset(&(priv->sensitivity_data), 0,
1044 	       sizeof(struct iwl_sensitivity_data));
1045 	memset(&(priv->chain_noise_data), 0,
1046 	       sizeof(struct iwl_chain_noise_data));
1047 	for (i = 0; i < NUM_RX_CHAINS; i++)
1048 		priv->chain_noise_data.delta_gain_code[i] =
1049 				CHAIN_NOISE_DELTA_GAIN_INIT_VAL;
1050 
1051 	/* Ask for statistics now, the uCode will send notification
1052 	 * periodically after association */
1053 	iwl_send_statistics_request(priv, CMD_ASYNC, true);
1054 }
1055