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_cmd cmd;
23 };
24 
25 struct statistics_general_data {
26 	u32 beacon_silence_rssi_a;
27 	u32 beacon_silence_rssi_b;
28 	u32 beacon_silence_rssi_c;
29 	u32 beacon_energy_a;
30 	u32 beacon_energy_b;
31 	u32 beacon_energy_c;
32 };
33 
34 int iwl_send_calib_results(struct iwl_priv *priv)
35 {
36 	struct iwl_host_cmd hcmd = {
37 		.id = REPLY_PHY_CALIBRATION_CMD,
38 	};
39 	struct iwl_calib_result *res;
40 
41 	list_for_each_entry(res, &priv->calib_results, list) {
42 		int ret;
43 
44 		hcmd.len[0] = res->cmd_len;
45 		hcmd.data[0] = &res->cmd;
46 		hcmd.dataflags[0] = IWL_HCMD_DFL_NOCOPY;
47 		ret = iwl_dvm_send_cmd(priv, &hcmd);
48 		if (ret) {
49 			IWL_ERR(priv, "Error %d on calib cmd %d\n",
50 				ret, res->cmd.hdr.op_code);
51 			return ret;
52 		}
53 	}
54 
55 	return 0;
56 }
57 
58 int iwl_calib_set(struct iwl_priv *priv,
59 		  const struct iwl_calib_cmd *cmd, size_t len)
60 {
61 	struct iwl_calib_result *res, *tmp;
62 
63 	if (check_sub_overflow(len, sizeof(*cmd), &len))
64 		return -ENOMEM;
65 
66 	res = kmalloc(struct_size(res, cmd.data, len), GFP_ATOMIC);
67 	if (!res)
68 		return -ENOMEM;
69 	res->cmd = *cmd;
70 	memcpy(res->cmd.data, cmd->data, len);
71 	res->cmd_len = struct_size(cmd, data, len);
72 
73 	list_for_each_entry(tmp, &priv->calib_results, list) {
74 		if (tmp->cmd.hdr.op_code == res->cmd.hdr.op_code) {
75 			list_replace(&tmp->list, &res->list);
76 			kfree(tmp);
77 			return 0;
78 		}
79 	}
80 
81 	/* wasn't in list already */
82 	list_add_tail(&res->list, &priv->calib_results);
83 
84 	return 0;
85 }
86 
87 void iwl_calib_free_results(struct iwl_priv *priv)
88 {
89 	struct iwl_calib_result *res, *tmp;
90 
91 	list_for_each_entry_safe(res, tmp, &priv->calib_results, list) {
92 		list_del(&res->list);
93 		kfree(res);
94 	}
95 }
96 
97 /*****************************************************************************
98  * RUNTIME calibrations framework
99  *****************************************************************************/
100 
101 /* "false alarms" are signals that our DSP tries to lock onto,
102  *   but then determines that they are either noise, or transmissions
103  *   from a distant wireless network (also "noise", really) that get
104  *   "stepped on" by stronger transmissions within our own network.
105  * This algorithm attempts to set a sensitivity level that is high
106  *   enough to receive all of our own network traffic, but not so
107  *   high that our DSP gets too busy trying to lock onto non-network
108  *   activity/noise. */
109 static int iwl_sens_energy_cck(struct iwl_priv *priv,
110 				   u32 norm_fa,
111 				   u32 rx_enable_time,
112 				   struct statistics_general_data *rx_info)
113 {
114 	u32 max_nrg_cck = 0;
115 	int i = 0;
116 	u8 max_silence_rssi = 0;
117 	u32 silence_ref = 0;
118 	u8 silence_rssi_a = 0;
119 	u8 silence_rssi_b = 0;
120 	u8 silence_rssi_c = 0;
121 	u32 val;
122 
123 	/* "false_alarms" values below are cross-multiplications to assess the
124 	 *   numbers of false alarms within the measured period of actual Rx
125 	 *   (Rx is off when we're txing), vs the min/max expected false alarms
126 	 *   (some should be expected if rx is sensitive enough) in a
127 	 *   hypothetical listening period of 200 time units (TU), 204.8 msec:
128 	 *
129 	 * MIN_FA/fixed-time < false_alarms/actual-rx-time < MAX_FA/beacon-time
130 	 *
131 	 * */
132 	u32 false_alarms = norm_fa * 200 * 1024;
133 	u32 max_false_alarms = MAX_FA_CCK * rx_enable_time;
134 	u32 min_false_alarms = MIN_FA_CCK * rx_enable_time;
135 	struct iwl_sensitivity_data *data = NULL;
136 	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
137 
138 	data = &(priv->sensitivity_data);
139 
140 	data->nrg_auto_corr_silence_diff = 0;
141 
142 	/* Find max silence rssi among all 3 receivers.
143 	 * This is background noise, which may include transmissions from other
144 	 *    networks, measured during silence before our network's beacon */
145 	silence_rssi_a = (u8)((rx_info->beacon_silence_rssi_a &
146 			    ALL_BAND_FILTER) >> 8);
147 	silence_rssi_b = (u8)((rx_info->beacon_silence_rssi_b &
148 			    ALL_BAND_FILTER) >> 8);
149 	silence_rssi_c = (u8)((rx_info->beacon_silence_rssi_c &
150 			    ALL_BAND_FILTER) >> 8);
151 
152 	val = max(silence_rssi_b, silence_rssi_c);
153 	max_silence_rssi = max(silence_rssi_a, (u8) val);
154 
155 	/* Store silence rssi in 20-beacon history table */
156 	data->nrg_silence_rssi[data->nrg_silence_idx] = max_silence_rssi;
157 	data->nrg_silence_idx++;
158 	if (data->nrg_silence_idx >= NRG_NUM_PREV_STAT_L)
159 		data->nrg_silence_idx = 0;
160 
161 	/* Find max silence rssi across 20 beacon history */
162 	for (i = 0; i < NRG_NUM_PREV_STAT_L; i++) {
163 		val = data->nrg_silence_rssi[i];
164 		silence_ref = max(silence_ref, val);
165 	}
166 	IWL_DEBUG_CALIB(priv, "silence a %u, b %u, c %u, 20-bcn max %u\n",
167 			silence_rssi_a, silence_rssi_b, silence_rssi_c,
168 			silence_ref);
169 
170 	/* Find max rx energy (min value!) among all 3 receivers,
171 	 *   measured during beacon frame.
172 	 * Save it in 10-beacon history table. */
173 	i = data->nrg_energy_idx;
174 	val = min(rx_info->beacon_energy_b, rx_info->beacon_energy_c);
175 	data->nrg_value[i] = min(rx_info->beacon_energy_a, val);
176 
177 	data->nrg_energy_idx++;
178 	if (data->nrg_energy_idx >= 10)
179 		data->nrg_energy_idx = 0;
180 
181 	/* Find min rx energy (max value) across 10 beacon history.
182 	 * This is the minimum signal level that we want to receive well.
183 	 * Add backoff (margin so we don't miss slightly lower energy frames).
184 	 * This establishes an upper bound (min value) for energy threshold. */
185 	max_nrg_cck = data->nrg_value[0];
186 	for (i = 1; i < 10; i++)
187 		max_nrg_cck = (u32) max(max_nrg_cck, (data->nrg_value[i]));
188 	max_nrg_cck += 6;
189 
190 	IWL_DEBUG_CALIB(priv, "rx energy a %u, b %u, c %u, 10-bcn max/min %u\n",
191 			rx_info->beacon_energy_a, rx_info->beacon_energy_b,
192 			rx_info->beacon_energy_c, max_nrg_cck - 6);
193 
194 	/* Count number of consecutive beacons with fewer-than-desired
195 	 *   false alarms. */
196 	if (false_alarms < min_false_alarms)
197 		data->num_in_cck_no_fa++;
198 	else
199 		data->num_in_cck_no_fa = 0;
200 	IWL_DEBUG_CALIB(priv, "consecutive bcns with few false alarms = %u\n",
201 			data->num_in_cck_no_fa);
202 
203 	/* If we got too many false alarms this time, reduce sensitivity */
204 	if ((false_alarms > max_false_alarms) &&
205 		(data->auto_corr_cck > AUTO_CORR_MAX_TH_CCK)) {
206 		IWL_DEBUG_CALIB(priv, "norm FA %u > max FA %u\n",
207 		     false_alarms, max_false_alarms);
208 		IWL_DEBUG_CALIB(priv, "... reducing sensitivity\n");
209 		data->nrg_curr_state = IWL_FA_TOO_MANY;
210 		/* Store for "fewer than desired" on later beacon */
211 		data->nrg_silence_ref = silence_ref;
212 
213 		/* increase energy threshold (reduce nrg value)
214 		 *   to decrease sensitivity */
215 		data->nrg_th_cck = data->nrg_th_cck - NRG_STEP_CCK;
216 	/* Else if we got fewer than desired, increase sensitivity */
217 	} else if (false_alarms < min_false_alarms) {
218 		data->nrg_curr_state = IWL_FA_TOO_FEW;
219 
220 		/* Compare silence level with silence level for most recent
221 		 *   healthy number or too many false alarms */
222 		data->nrg_auto_corr_silence_diff = (s32)data->nrg_silence_ref -
223 						   (s32)silence_ref;
224 
225 		IWL_DEBUG_CALIB(priv, "norm FA %u < min FA %u, silence diff %d\n",
226 			 false_alarms, min_false_alarms,
227 			 data->nrg_auto_corr_silence_diff);
228 
229 		/* Increase value to increase sensitivity, but only if:
230 		 * 1a) previous beacon did *not* have *too many* false alarms
231 		 * 1b) AND there's a significant difference in Rx levels
232 		 *      from a previous beacon with too many, or healthy # FAs
233 		 * OR 2) We've seen a lot of beacons (100) with too few
234 		 *       false alarms */
235 		if ((data->nrg_prev_state != IWL_FA_TOO_MANY) &&
236 			((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
237 			(data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {
238 
239 			IWL_DEBUG_CALIB(priv, "... increasing sensitivity\n");
240 			/* Increase nrg value to increase sensitivity */
241 			val = data->nrg_th_cck + NRG_STEP_CCK;
242 			data->nrg_th_cck = min((u32)ranges->min_nrg_cck, val);
243 		} else {
244 			IWL_DEBUG_CALIB(priv, "... but not changing sensitivity\n");
245 		}
246 
247 	/* Else we got a healthy number of false alarms, keep status quo */
248 	} else {
249 		IWL_DEBUG_CALIB(priv, " FA in safe zone\n");
250 		data->nrg_curr_state = IWL_FA_GOOD_RANGE;
251 
252 		/* Store for use in "fewer than desired" with later beacon */
253 		data->nrg_silence_ref = silence_ref;
254 
255 		/* If previous beacon had too many false alarms,
256 		 *   give it some extra margin by reducing sensitivity again
257 		 *   (but don't go below measured energy of desired Rx) */
258 		if (data->nrg_prev_state == IWL_FA_TOO_MANY) {
259 			IWL_DEBUG_CALIB(priv, "... increasing margin\n");
260 			if (data->nrg_th_cck > (max_nrg_cck + NRG_MARGIN))
261 				data->nrg_th_cck -= NRG_MARGIN;
262 			else
263 				data->nrg_th_cck = max_nrg_cck;
264 		}
265 	}
266 
267 	/* Make sure the energy threshold does not go above the measured
268 	 * energy of the desired Rx signals (reduced by backoff margin),
269 	 * or else we might start missing Rx frames.
270 	 * Lower value is higher energy, so we use max()!
271 	 */
272 	data->nrg_th_cck = max(max_nrg_cck, data->nrg_th_cck);
273 	IWL_DEBUG_CALIB(priv, "new nrg_th_cck %u\n", data->nrg_th_cck);
274 
275 	data->nrg_prev_state = data->nrg_curr_state;
276 
277 	/* Auto-correlation CCK algorithm */
278 	if (false_alarms > min_false_alarms) {
279 
280 		/* increase auto_corr values to decrease sensitivity
281 		 * so the DSP won't be disturbed by the noise
282 		 */
283 		if (data->auto_corr_cck < AUTO_CORR_MAX_TH_CCK)
284 			data->auto_corr_cck = AUTO_CORR_MAX_TH_CCK + 1;
285 		else {
286 			val = data->auto_corr_cck + AUTO_CORR_STEP_CCK;
287 			data->auto_corr_cck =
288 				min((u32)ranges->auto_corr_max_cck, val);
289 		}
290 		val = data->auto_corr_cck_mrc + AUTO_CORR_STEP_CCK;
291 		data->auto_corr_cck_mrc =
292 			min((u32)ranges->auto_corr_max_cck_mrc, val);
293 	} else if ((false_alarms < min_false_alarms) &&
294 	   ((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
295 	   (data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {
296 
297 		/* Decrease auto_corr values to increase sensitivity */
298 		val = data->auto_corr_cck - AUTO_CORR_STEP_CCK;
299 		data->auto_corr_cck =
300 			max((u32)ranges->auto_corr_min_cck, val);
301 		val = data->auto_corr_cck_mrc - AUTO_CORR_STEP_CCK;
302 		data->auto_corr_cck_mrc =
303 			max((u32)ranges->auto_corr_min_cck_mrc, val);
304 	}
305 
306 	return 0;
307 }
308 
309 
310 static int iwl_sens_auto_corr_ofdm(struct iwl_priv *priv,
311 				       u32 norm_fa,
312 				       u32 rx_enable_time)
313 {
314 	u32 val;
315 	u32 false_alarms = norm_fa * 200 * 1024;
316 	u32 max_false_alarms = MAX_FA_OFDM * rx_enable_time;
317 	u32 min_false_alarms = MIN_FA_OFDM * rx_enable_time;
318 	struct iwl_sensitivity_data *data = NULL;
319 	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
320 
321 	data = &(priv->sensitivity_data);
322 
323 	/* If we got too many false alarms this time, reduce sensitivity */
324 	if (false_alarms > max_false_alarms) {
325 
326 		IWL_DEBUG_CALIB(priv, "norm FA %u > max FA %u)\n",
327 			     false_alarms, max_false_alarms);
328 
329 		val = data->auto_corr_ofdm + AUTO_CORR_STEP_OFDM;
330 		data->auto_corr_ofdm =
331 			min((u32)ranges->auto_corr_max_ofdm, val);
332 
333 		val = data->auto_corr_ofdm_mrc + AUTO_CORR_STEP_OFDM;
334 		data->auto_corr_ofdm_mrc =
335 			min((u32)ranges->auto_corr_max_ofdm_mrc, val);
336 
337 		val = data->auto_corr_ofdm_x1 + AUTO_CORR_STEP_OFDM;
338 		data->auto_corr_ofdm_x1 =
339 			min((u32)ranges->auto_corr_max_ofdm_x1, val);
340 
341 		val = data->auto_corr_ofdm_mrc_x1 + AUTO_CORR_STEP_OFDM;
342 		data->auto_corr_ofdm_mrc_x1 =
343 			min((u32)ranges->auto_corr_max_ofdm_mrc_x1, val);
344 	}
345 
346 	/* Else if we got fewer than desired, increase sensitivity */
347 	else if (false_alarms < min_false_alarms) {
348 
349 		IWL_DEBUG_CALIB(priv, "norm FA %u < min FA %u\n",
350 			     false_alarms, min_false_alarms);
351 
352 		val = data->auto_corr_ofdm - AUTO_CORR_STEP_OFDM;
353 		data->auto_corr_ofdm =
354 			max((u32)ranges->auto_corr_min_ofdm, val);
355 
356 		val = data->auto_corr_ofdm_mrc - AUTO_CORR_STEP_OFDM;
357 		data->auto_corr_ofdm_mrc =
358 			max((u32)ranges->auto_corr_min_ofdm_mrc, val);
359 
360 		val = data->auto_corr_ofdm_x1 - AUTO_CORR_STEP_OFDM;
361 		data->auto_corr_ofdm_x1 =
362 			max((u32)ranges->auto_corr_min_ofdm_x1, val);
363 
364 		val = data->auto_corr_ofdm_mrc_x1 - AUTO_CORR_STEP_OFDM;
365 		data->auto_corr_ofdm_mrc_x1 =
366 			max((u32)ranges->auto_corr_min_ofdm_mrc_x1, val);
367 	} else {
368 		IWL_DEBUG_CALIB(priv, "min FA %u < norm FA %u < max FA %u OK\n",
369 			 min_false_alarms, false_alarms, max_false_alarms);
370 	}
371 	return 0;
372 }
373 
374 static void iwl_prepare_legacy_sensitivity_tbl(struct iwl_priv *priv,
375 				struct iwl_sensitivity_data *data,
376 				__le16 *tbl)
377 {
378 	tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_INDEX] =
379 				cpu_to_le16((u16)data->auto_corr_ofdm);
380 	tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_MRC_INDEX] =
381 				cpu_to_le16((u16)data->auto_corr_ofdm_mrc);
382 	tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_INDEX] =
383 				cpu_to_le16((u16)data->auto_corr_ofdm_x1);
384 	tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_MRC_INDEX] =
385 				cpu_to_le16((u16)data->auto_corr_ofdm_mrc_x1);
386 
387 	tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_INDEX] =
388 				cpu_to_le16((u16)data->auto_corr_cck);
389 	tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_MRC_INDEX] =
390 				cpu_to_le16((u16)data->auto_corr_cck_mrc);
391 
392 	tbl[HD_MIN_ENERGY_CCK_DET_INDEX] =
393 				cpu_to_le16((u16)data->nrg_th_cck);
394 	tbl[HD_MIN_ENERGY_OFDM_DET_INDEX] =
395 				cpu_to_le16((u16)data->nrg_th_ofdm);
396 
397 	tbl[HD_BARKER_CORR_TH_ADD_MIN_INDEX] =
398 				cpu_to_le16(data->barker_corr_th_min);
399 	tbl[HD_BARKER_CORR_TH_ADD_MIN_MRC_INDEX] =
400 				cpu_to_le16(data->barker_corr_th_min_mrc);
401 	tbl[HD_OFDM_ENERGY_TH_IN_INDEX] =
402 				cpu_to_le16(data->nrg_th_cca);
403 
404 	IWL_DEBUG_CALIB(priv, "ofdm: ac %u mrc %u x1 %u mrc_x1 %u thresh %u\n",
405 			data->auto_corr_ofdm, data->auto_corr_ofdm_mrc,
406 			data->auto_corr_ofdm_x1, data->auto_corr_ofdm_mrc_x1,
407 			data->nrg_th_ofdm);
408 
409 	IWL_DEBUG_CALIB(priv, "cck: ac %u mrc %u thresh %u\n",
410 			data->auto_corr_cck, data->auto_corr_cck_mrc,
411 			data->nrg_th_cck);
412 }
413 
414 /* Prepare a SENSITIVITY_CMD, send to uCode if values have changed */
415 static int iwl_sensitivity_write(struct iwl_priv *priv)
416 {
417 	struct iwl_sensitivity_cmd cmd;
418 	struct iwl_sensitivity_data *data = NULL;
419 	struct iwl_host_cmd cmd_out = {
420 		.id = SENSITIVITY_CMD,
421 		.len = { sizeof(struct iwl_sensitivity_cmd), },
422 		.flags = CMD_ASYNC,
423 		.data = { &cmd, },
424 	};
425 
426 	data = &(priv->sensitivity_data);
427 
428 	memset(&cmd, 0, sizeof(cmd));
429 
430 	iwl_prepare_legacy_sensitivity_tbl(priv, data, &cmd.table[0]);
431 
432 	/* Update uCode's "work" table, and copy it to DSP */
433 	cmd.control = SENSITIVITY_CMD_CONTROL_WORK_TABLE;
434 
435 	/* Don't send command to uCode if nothing has changed */
436 	if (!memcmp(&cmd.table[0], &(priv->sensitivity_tbl[0]),
437 		    sizeof(u16)*HD_TABLE_SIZE)) {
438 		IWL_DEBUG_CALIB(priv, "No change in SENSITIVITY_CMD\n");
439 		return 0;
440 	}
441 
442 	/* Copy table for comparison next time */
443 	memcpy(&(priv->sensitivity_tbl[0]), &(cmd.table[0]),
444 	       sizeof(u16)*HD_TABLE_SIZE);
445 
446 	return iwl_dvm_send_cmd(priv, &cmd_out);
447 }
448 
449 /* Prepare a SENSITIVITY_CMD, send to uCode if values have changed */
450 static int iwl_enhance_sensitivity_write(struct iwl_priv *priv)
451 {
452 	struct iwl_enhance_sensitivity_cmd cmd;
453 	struct iwl_sensitivity_data *data = NULL;
454 	struct iwl_host_cmd cmd_out = {
455 		.id = SENSITIVITY_CMD,
456 		.len = { sizeof(struct iwl_enhance_sensitivity_cmd), },
457 		.flags = CMD_ASYNC,
458 		.data = { &cmd, },
459 	};
460 
461 	data = &(priv->sensitivity_data);
462 
463 	memset(&cmd, 0, sizeof(cmd));
464 
465 	iwl_prepare_legacy_sensitivity_tbl(priv, data, &cmd.enhance_table[0]);
466 
467 	if (priv->lib->hd_v2) {
468 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX] =
469 			HD_INA_NON_SQUARE_DET_OFDM_DATA_V2;
470 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_CCK_INDEX] =
471 			HD_INA_NON_SQUARE_DET_CCK_DATA_V2;
472 		cmd.enhance_table[HD_CORR_11_INSTEAD_OF_CORR_9_EN_INDEX] =
473 			HD_CORR_11_INSTEAD_OF_CORR_9_EN_DATA_V2;
474 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
475 			HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_DATA_V2;
476 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
477 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V2;
478 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_INDEX] =
479 			HD_OFDM_NON_SQUARE_DET_SLOPE_DATA_V2;
480 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_INDEX] =
481 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_DATA_V2;
482 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
483 			HD_CCK_NON_SQUARE_DET_SLOPE_MRC_DATA_V2;
484 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
485 			HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V2;
486 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_INDEX] =
487 			HD_CCK_NON_SQUARE_DET_SLOPE_DATA_V2;
488 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_INDEX] =
489 			HD_CCK_NON_SQUARE_DET_INTERCEPT_DATA_V2;
490 	} else {
491 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX] =
492 			HD_INA_NON_SQUARE_DET_OFDM_DATA_V1;
493 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_CCK_INDEX] =
494 			HD_INA_NON_SQUARE_DET_CCK_DATA_V1;
495 		cmd.enhance_table[HD_CORR_11_INSTEAD_OF_CORR_9_EN_INDEX] =
496 			HD_CORR_11_INSTEAD_OF_CORR_9_EN_DATA_V1;
497 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
498 			HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_DATA_V1;
499 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
500 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V1;
501 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_INDEX] =
502 			HD_OFDM_NON_SQUARE_DET_SLOPE_DATA_V1;
503 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_INDEX] =
504 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_DATA_V1;
505 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
506 			HD_CCK_NON_SQUARE_DET_SLOPE_MRC_DATA_V1;
507 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
508 			HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V1;
509 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_INDEX] =
510 			HD_CCK_NON_SQUARE_DET_SLOPE_DATA_V1;
511 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_INDEX] =
512 			HD_CCK_NON_SQUARE_DET_INTERCEPT_DATA_V1;
513 	}
514 
515 	/* Update uCode's "work" table, and copy it to DSP */
516 	cmd.control = SENSITIVITY_CMD_CONTROL_WORK_TABLE;
517 
518 	/* Don't send command to uCode if nothing has changed */
519 	if (!memcmp(&cmd.enhance_table[0], &(priv->sensitivity_tbl[0]),
520 		    sizeof(u16)*HD_TABLE_SIZE) &&
521 	    !memcmp(&cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX],
522 		    &(priv->enhance_sensitivity_tbl[0]),
523 		    sizeof(u16)*ENHANCE_HD_TABLE_ENTRIES)) {
524 		IWL_DEBUG_CALIB(priv, "No change in SENSITIVITY_CMD\n");
525 		return 0;
526 	}
527 
528 	/* Copy table for comparison next time */
529 	memcpy(&(priv->sensitivity_tbl[0]), &(cmd.enhance_table[0]),
530 	       sizeof(u16)*HD_TABLE_SIZE);
531 	memcpy(&(priv->enhance_sensitivity_tbl[0]),
532 	       &(cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX]),
533 	       sizeof(u16)*ENHANCE_HD_TABLE_ENTRIES);
534 
535 	return iwl_dvm_send_cmd(priv, &cmd_out);
536 }
537 
538 void iwl_init_sensitivity(struct iwl_priv *priv)
539 {
540 	int ret = 0;
541 	int i;
542 	struct iwl_sensitivity_data *data = NULL;
543 	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
544 
545 	if (priv->calib_disabled & IWL_SENSITIVITY_CALIB_DISABLED)
546 		return;
547 
548 	IWL_DEBUG_CALIB(priv, "Start iwl_init_sensitivity\n");
549 
550 	/* Clear driver's sensitivity algo data */
551 	data = &(priv->sensitivity_data);
552 
553 	if (ranges == NULL)
554 		return;
555 
556 	memset(data, 0, sizeof(struct iwl_sensitivity_data));
557 
558 	data->num_in_cck_no_fa = 0;
559 	data->nrg_curr_state = IWL_FA_TOO_MANY;
560 	data->nrg_prev_state = IWL_FA_TOO_MANY;
561 	data->nrg_silence_ref = 0;
562 	data->nrg_silence_idx = 0;
563 	data->nrg_energy_idx = 0;
564 
565 	for (i = 0; i < 10; i++)
566 		data->nrg_value[i] = 0;
567 
568 	for (i = 0; i < NRG_NUM_PREV_STAT_L; i++)
569 		data->nrg_silence_rssi[i] = 0;
570 
571 	data->auto_corr_ofdm =  ranges->auto_corr_min_ofdm;
572 	data->auto_corr_ofdm_mrc = ranges->auto_corr_min_ofdm_mrc;
573 	data->auto_corr_ofdm_x1  = ranges->auto_corr_min_ofdm_x1;
574 	data->auto_corr_ofdm_mrc_x1 = ranges->auto_corr_min_ofdm_mrc_x1;
575 	data->auto_corr_cck = AUTO_CORR_CCK_MIN_VAL_DEF;
576 	data->auto_corr_cck_mrc = ranges->auto_corr_min_cck_mrc;
577 	data->nrg_th_cck = ranges->nrg_th_cck;
578 	data->nrg_th_ofdm = ranges->nrg_th_ofdm;
579 	data->barker_corr_th_min = ranges->barker_corr_th_min;
580 	data->barker_corr_th_min_mrc = ranges->barker_corr_th_min_mrc;
581 	data->nrg_th_cca = ranges->nrg_th_cca;
582 
583 	data->last_bad_plcp_cnt_ofdm = 0;
584 	data->last_fa_cnt_ofdm = 0;
585 	data->last_bad_plcp_cnt_cck = 0;
586 	data->last_fa_cnt_cck = 0;
587 
588 	if (priv->fw->enhance_sensitivity_table)
589 		ret |= iwl_enhance_sensitivity_write(priv);
590 	else
591 		ret |= iwl_sensitivity_write(priv);
592 	IWL_DEBUG_CALIB(priv, "<<return 0x%X\n", ret);
593 }
594 
595 void iwl_sensitivity_calibration(struct iwl_priv *priv)
596 {
597 	u32 rx_enable_time;
598 	u32 fa_cck;
599 	u32 fa_ofdm;
600 	u32 bad_plcp_cck;
601 	u32 bad_plcp_ofdm;
602 	u32 norm_fa_ofdm;
603 	u32 norm_fa_cck;
604 	struct iwl_sensitivity_data *data = NULL;
605 	struct statistics_rx_non_phy *rx_info;
606 	struct statistics_rx_phy *ofdm, *cck;
607 	struct statistics_general_data statis;
608 
609 	if (priv->calib_disabled & IWL_SENSITIVITY_CALIB_DISABLED)
610 		return;
611 
612 	data = &(priv->sensitivity_data);
613 
614 	if (!iwl_is_any_associated(priv)) {
615 		IWL_DEBUG_CALIB(priv, "<< - not associated\n");
616 		return;
617 	}
618 
619 	spin_lock_bh(&priv->statistics.lock);
620 	rx_info = &priv->statistics.rx_non_phy;
621 	ofdm = &priv->statistics.rx_ofdm;
622 	cck = &priv->statistics.rx_cck;
623 	if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
624 		IWL_DEBUG_CALIB(priv, "<< invalid data.\n");
625 		spin_unlock_bh(&priv->statistics.lock);
626 		return;
627 	}
628 
629 	/* Extract Statistics: */
630 	rx_enable_time = le32_to_cpu(rx_info->channel_load);
631 	fa_cck = le32_to_cpu(cck->false_alarm_cnt);
632 	fa_ofdm = le32_to_cpu(ofdm->false_alarm_cnt);
633 	bad_plcp_cck = le32_to_cpu(cck->plcp_err);
634 	bad_plcp_ofdm = le32_to_cpu(ofdm->plcp_err);
635 
636 	statis.beacon_silence_rssi_a =
637 			le32_to_cpu(rx_info->beacon_silence_rssi_a);
638 	statis.beacon_silence_rssi_b =
639 			le32_to_cpu(rx_info->beacon_silence_rssi_b);
640 	statis.beacon_silence_rssi_c =
641 			le32_to_cpu(rx_info->beacon_silence_rssi_c);
642 	statis.beacon_energy_a =
643 			le32_to_cpu(rx_info->beacon_energy_a);
644 	statis.beacon_energy_b =
645 			le32_to_cpu(rx_info->beacon_energy_b);
646 	statis.beacon_energy_c =
647 			le32_to_cpu(rx_info->beacon_energy_c);
648 
649 	spin_unlock_bh(&priv->statistics.lock);
650 
651 	IWL_DEBUG_CALIB(priv, "rx_enable_time = %u usecs\n", rx_enable_time);
652 
653 	if (!rx_enable_time) {
654 		IWL_DEBUG_CALIB(priv, "<< RX Enable Time == 0!\n");
655 		return;
656 	}
657 
658 	/* These statistics increase monotonically, and do not reset
659 	 *   at each beacon.  Calculate difference from last value, or just
660 	 *   use the new statistics value if it has reset or wrapped around. */
661 	if (data->last_bad_plcp_cnt_cck > bad_plcp_cck)
662 		data->last_bad_plcp_cnt_cck = bad_plcp_cck;
663 	else {
664 		bad_plcp_cck -= data->last_bad_plcp_cnt_cck;
665 		data->last_bad_plcp_cnt_cck += bad_plcp_cck;
666 	}
667 
668 	if (data->last_bad_plcp_cnt_ofdm > bad_plcp_ofdm)
669 		data->last_bad_plcp_cnt_ofdm = bad_plcp_ofdm;
670 	else {
671 		bad_plcp_ofdm -= data->last_bad_plcp_cnt_ofdm;
672 		data->last_bad_plcp_cnt_ofdm += bad_plcp_ofdm;
673 	}
674 
675 	if (data->last_fa_cnt_ofdm > fa_ofdm)
676 		data->last_fa_cnt_ofdm = fa_ofdm;
677 	else {
678 		fa_ofdm -= data->last_fa_cnt_ofdm;
679 		data->last_fa_cnt_ofdm += fa_ofdm;
680 	}
681 
682 	if (data->last_fa_cnt_cck > fa_cck)
683 		data->last_fa_cnt_cck = fa_cck;
684 	else {
685 		fa_cck -= data->last_fa_cnt_cck;
686 		data->last_fa_cnt_cck += fa_cck;
687 	}
688 
689 	/* Total aborted signal locks */
690 	norm_fa_ofdm = fa_ofdm + bad_plcp_ofdm;
691 	norm_fa_cck = fa_cck + bad_plcp_cck;
692 
693 	IWL_DEBUG_CALIB(priv, "cck: fa %u badp %u  ofdm: fa %u badp %u\n", fa_cck,
694 			bad_plcp_cck, fa_ofdm, bad_plcp_ofdm);
695 
696 	iwl_sens_auto_corr_ofdm(priv, norm_fa_ofdm, rx_enable_time);
697 	iwl_sens_energy_cck(priv, norm_fa_cck, rx_enable_time, &statis);
698 	if (priv->fw->enhance_sensitivity_table)
699 		iwl_enhance_sensitivity_write(priv);
700 	else
701 		iwl_sensitivity_write(priv);
702 }
703 
704 static inline u8 find_first_chain(u8 mask)
705 {
706 	if (mask & ANT_A)
707 		return CHAIN_A;
708 	if (mask & ANT_B)
709 		return CHAIN_B;
710 	return CHAIN_C;
711 }
712 
713 /*
714  * Run disconnected antenna algorithm to find out which antennas are
715  * disconnected.
716  */
717 static void iwl_find_disconn_antenna(struct iwl_priv *priv, u32* average_sig,
718 				     struct iwl_chain_noise_data *data)
719 {
720 	u32 active_chains = 0;
721 	u32 max_average_sig;
722 	u16 max_average_sig_antenna_i;
723 	u8 num_tx_chains;
724 	u8 first_chain;
725 	u16 i = 0;
726 
727 	average_sig[0] = data->chain_signal_a / IWL_CAL_NUM_BEACONS;
728 	average_sig[1] = data->chain_signal_b / IWL_CAL_NUM_BEACONS;
729 	average_sig[2] = data->chain_signal_c / IWL_CAL_NUM_BEACONS;
730 
731 	if (average_sig[0] >= average_sig[1]) {
732 		max_average_sig = average_sig[0];
733 		max_average_sig_antenna_i = 0;
734 		active_chains = (1 << max_average_sig_antenna_i);
735 	} else {
736 		max_average_sig = average_sig[1];
737 		max_average_sig_antenna_i = 1;
738 		active_chains = (1 << max_average_sig_antenna_i);
739 	}
740 
741 	if (average_sig[2] >= max_average_sig) {
742 		max_average_sig = average_sig[2];
743 		max_average_sig_antenna_i = 2;
744 		active_chains = (1 << max_average_sig_antenna_i);
745 	}
746 
747 	IWL_DEBUG_CALIB(priv, "average_sig: a %d b %d c %d\n",
748 		     average_sig[0], average_sig[1], average_sig[2]);
749 	IWL_DEBUG_CALIB(priv, "max_average_sig = %d, antenna %d\n",
750 		     max_average_sig, max_average_sig_antenna_i);
751 
752 	/* Compare signal strengths for all 3 receivers. */
753 	for (i = 0; i < NUM_RX_CHAINS; i++) {
754 		if (i != max_average_sig_antenna_i) {
755 			s32 rssi_delta = (max_average_sig - average_sig[i]);
756 
757 			/* If signal is very weak, compared with
758 			 * strongest, mark it as disconnected. */
759 			if (rssi_delta > MAXIMUM_ALLOWED_PATHLOSS)
760 				data->disconn_array[i] = 1;
761 			else
762 				active_chains |= (1 << i);
763 			IWL_DEBUG_CALIB(priv, "i = %d  rssiDelta = %d  "
764 			     "disconn_array[i] = %d\n",
765 			     i, rssi_delta, data->disconn_array[i]);
766 		}
767 	}
768 
769 	/*
770 	 * The above algorithm sometimes fails when the ucode
771 	 * reports 0 for all chains. It's not clear why that
772 	 * happens to start with, but it is then causing trouble
773 	 * because this can make us enable more chains than the
774 	 * hardware really has.
775 	 *
776 	 * To be safe, simply mask out any chains that we know
777 	 * are not on the device.
778 	 */
779 	active_chains &= priv->nvm_data->valid_rx_ant;
780 
781 	num_tx_chains = 0;
782 	for (i = 0; i < NUM_RX_CHAINS; i++) {
783 		/* loops on all the bits of
784 		 * priv->hw_setting.valid_tx_ant */
785 		u8 ant_msk = (1 << i);
786 		if (!(priv->nvm_data->valid_tx_ant & ant_msk))
787 			continue;
788 
789 		num_tx_chains++;
790 		if (data->disconn_array[i] == 0)
791 			/* there is a Tx antenna connected */
792 			break;
793 		if (num_tx_chains == priv->hw_params.tx_chains_num &&
794 		    data->disconn_array[i]) {
795 			/*
796 			 * If all chains are disconnected
797 			 * connect the first valid tx chain
798 			 */
799 			first_chain =
800 				find_first_chain(priv->nvm_data->valid_tx_ant);
801 			data->disconn_array[first_chain] = 0;
802 			active_chains |= BIT(first_chain);
803 			IWL_DEBUG_CALIB(priv,
804 					"All Tx chains are disconnected W/A - declare %d as connected\n",
805 					first_chain);
806 			break;
807 		}
808 	}
809 
810 	if (active_chains != priv->nvm_data->valid_rx_ant &&
811 	    active_chains != priv->chain_noise_data.active_chains)
812 		IWL_DEBUG_CALIB(priv,
813 				"Detected that not all antennas are connected! "
814 				"Connected: %#x, valid: %#x.\n",
815 				active_chains,
816 				priv->nvm_data->valid_rx_ant);
817 
818 	/* Save for use within RXON, TX, SCAN commands, etc. */
819 	data->active_chains = active_chains;
820 	IWL_DEBUG_CALIB(priv, "active_chains (bitwise) = 0x%x\n",
821 			active_chains);
822 }
823 
824 static void iwlagn_gain_computation(struct iwl_priv *priv,
825 				    u32 average_noise[NUM_RX_CHAINS],
826 				    u8 default_chain)
827 {
828 	int i;
829 	s32 delta_g;
830 	struct iwl_chain_noise_data *data = &priv->chain_noise_data;
831 
832 	/*
833 	 * Find Gain Code for the chains based on "default chain"
834 	 */
835 	for (i = default_chain + 1; i < NUM_RX_CHAINS; i++) {
836 		if ((data->disconn_array[i])) {
837 			data->delta_gain_code[i] = 0;
838 			continue;
839 		}
840 
841 		delta_g = (priv->lib->chain_noise_scale *
842 			((s32)average_noise[default_chain] -
843 			(s32)average_noise[i])) / 1500;
844 
845 		/* bound gain by 2 bits value max, 3rd bit is sign */
846 		data->delta_gain_code[i] =
847 			min(abs(delta_g), CHAIN_NOISE_MAX_DELTA_GAIN_CODE);
848 
849 		if (delta_g < 0)
850 			/*
851 			 * set negative sign ...
852 			 * note to Intel developers:  This is uCode API format,
853 			 *   not the format of any internal device registers.
854 			 *   Do not change this format for e.g. 6050 or similar
855 			 *   devices.  Change format only if more resolution
856 			 *   (i.e. more than 2 bits magnitude) is needed.
857 			 */
858 			data->delta_gain_code[i] |= (1 << 2);
859 	}
860 
861 	IWL_DEBUG_CALIB(priv, "Delta gains: ANT_B = %d  ANT_C = %d\n",
862 			data->delta_gain_code[1], data->delta_gain_code[2]);
863 
864 	if (!data->radio_write) {
865 		struct iwl_calib_chain_noise_gain_cmd cmd;
866 
867 		memset(&cmd, 0, sizeof(cmd));
868 
869 		iwl_set_calib_hdr(&cmd.hdr,
870 			priv->phy_calib_chain_noise_gain_cmd);
871 		cmd.delta_gain_1 = data->delta_gain_code[1];
872 		cmd.delta_gain_2 = data->delta_gain_code[2];
873 		iwl_dvm_send_cmd_pdu(priv, REPLY_PHY_CALIBRATION_CMD,
874 			CMD_ASYNC, sizeof(cmd), &cmd);
875 
876 		data->radio_write = 1;
877 		data->state = IWL_CHAIN_NOISE_CALIBRATED;
878 	}
879 }
880 
881 /*
882  * Accumulate 16 beacons of signal and noise statistics for each of
883  *   3 receivers/antennas/rx-chains, then figure out:
884  * 1)  Which antennas are connected.
885  * 2)  Differential rx gain settings to balance the 3 receivers.
886  */
887 void iwl_chain_noise_calibration(struct iwl_priv *priv)
888 {
889 	struct iwl_chain_noise_data *data = NULL;
890 
891 	u32 chain_noise_a;
892 	u32 chain_noise_b;
893 	u32 chain_noise_c;
894 	u32 chain_sig_a;
895 	u32 chain_sig_b;
896 	u32 chain_sig_c;
897 	u32 average_sig[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
898 	u32 average_noise[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
899 	u32 min_average_noise = MIN_AVERAGE_NOISE_MAX_VALUE;
900 	u16 min_average_noise_antenna_i = INITIALIZATION_VALUE;
901 	u16 i = 0;
902 	u16 rxon_chnum = INITIALIZATION_VALUE;
903 	u16 stat_chnum = INITIALIZATION_VALUE;
904 	u8 rxon_band24;
905 	u8 stat_band24;
906 	struct statistics_rx_non_phy *rx_info;
907 
908 	/*
909 	 * MULTI-FIXME:
910 	 * When we support multiple interfaces on different channels,
911 	 * this must be modified/fixed.
912 	 */
913 	struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
914 
915 	if (priv->calib_disabled & IWL_CHAIN_NOISE_CALIB_DISABLED)
916 		return;
917 
918 	data = &(priv->chain_noise_data);
919 
920 	/*
921 	 * Accumulate just the first "chain_noise_num_beacons" after
922 	 * the first association, then we're done forever.
923 	 */
924 	if (data->state != IWL_CHAIN_NOISE_ACCUMULATE) {
925 		if (data->state == IWL_CHAIN_NOISE_ALIVE)
926 			IWL_DEBUG_CALIB(priv, "Wait for noise calib reset\n");
927 		return;
928 	}
929 
930 	spin_lock_bh(&priv->statistics.lock);
931 
932 	rx_info = &priv->statistics.rx_non_phy;
933 
934 	if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
935 		IWL_DEBUG_CALIB(priv, " << Interference data unavailable\n");
936 		spin_unlock_bh(&priv->statistics.lock);
937 		return;
938 	}
939 
940 	rxon_band24 = !!(ctx->staging.flags & RXON_FLG_BAND_24G_MSK);
941 	rxon_chnum = le16_to_cpu(ctx->staging.channel);
942 	stat_band24 =
943 		!!(priv->statistics.flag & STATISTICS_REPLY_FLG_BAND_24G_MSK);
944 	stat_chnum = le32_to_cpu(priv->statistics.flag) >> 16;
945 
946 	/* Make sure we accumulate data for just the associated channel
947 	 *   (even if scanning). */
948 	if ((rxon_chnum != stat_chnum) || (rxon_band24 != stat_band24)) {
949 		IWL_DEBUG_CALIB(priv, "Stats not from chan=%d, band24=%d\n",
950 				rxon_chnum, rxon_band24);
951 		spin_unlock_bh(&priv->statistics.lock);
952 		return;
953 	}
954 
955 	/*
956 	 *  Accumulate beacon statistics values across
957 	 * "chain_noise_num_beacons"
958 	 */
959 	chain_noise_a = le32_to_cpu(rx_info->beacon_silence_rssi_a) &
960 				IN_BAND_FILTER;
961 	chain_noise_b = le32_to_cpu(rx_info->beacon_silence_rssi_b) &
962 				IN_BAND_FILTER;
963 	chain_noise_c = le32_to_cpu(rx_info->beacon_silence_rssi_c) &
964 				IN_BAND_FILTER;
965 
966 	chain_sig_a = le32_to_cpu(rx_info->beacon_rssi_a) & IN_BAND_FILTER;
967 	chain_sig_b = le32_to_cpu(rx_info->beacon_rssi_b) & IN_BAND_FILTER;
968 	chain_sig_c = le32_to_cpu(rx_info->beacon_rssi_c) & IN_BAND_FILTER;
969 
970 	spin_unlock_bh(&priv->statistics.lock);
971 
972 	data->beacon_count++;
973 
974 	data->chain_noise_a = (chain_noise_a + data->chain_noise_a);
975 	data->chain_noise_b = (chain_noise_b + data->chain_noise_b);
976 	data->chain_noise_c = (chain_noise_c + data->chain_noise_c);
977 
978 	data->chain_signal_a = (chain_sig_a + data->chain_signal_a);
979 	data->chain_signal_b = (chain_sig_b + data->chain_signal_b);
980 	data->chain_signal_c = (chain_sig_c + data->chain_signal_c);
981 
982 	IWL_DEBUG_CALIB(priv, "chan=%d, band24=%d, beacon=%d\n",
983 			rxon_chnum, rxon_band24, data->beacon_count);
984 	IWL_DEBUG_CALIB(priv, "chain_sig: a %d b %d c %d\n",
985 			chain_sig_a, chain_sig_b, chain_sig_c);
986 	IWL_DEBUG_CALIB(priv, "chain_noise: a %d b %d c %d\n",
987 			chain_noise_a, chain_noise_b, chain_noise_c);
988 
989 	/* If this is the "chain_noise_num_beacons", determine:
990 	 * 1)  Disconnected antennas (using signal strengths)
991 	 * 2)  Differential gain (using silence noise) to balance receivers */
992 	if (data->beacon_count != IWL_CAL_NUM_BEACONS)
993 		return;
994 
995 	/* Analyze signal for disconnected antenna */
996 	if (priv->lib->bt_params &&
997 	    priv->lib->bt_params->advanced_bt_coexist) {
998 		/* Disable disconnected antenna algorithm for advanced
999 		   bt coex, assuming valid antennas are connected */
1000 		data->active_chains = priv->nvm_data->valid_rx_ant;
1001 		for (i = 0; i < NUM_RX_CHAINS; i++)
1002 			if (!(data->active_chains & (1<<i)))
1003 				data->disconn_array[i] = 1;
1004 	} else
1005 		iwl_find_disconn_antenna(priv, average_sig, data);
1006 
1007 	/* Analyze noise for rx balance */
1008 	average_noise[0] = data->chain_noise_a / IWL_CAL_NUM_BEACONS;
1009 	average_noise[1] = data->chain_noise_b / IWL_CAL_NUM_BEACONS;
1010 	average_noise[2] = data->chain_noise_c / IWL_CAL_NUM_BEACONS;
1011 
1012 	for (i = 0; i < NUM_RX_CHAINS; i++) {
1013 		if (!(data->disconn_array[i]) &&
1014 		   (average_noise[i] <= min_average_noise)) {
1015 			/* This means that chain i is active and has
1016 			 * lower noise values so far: */
1017 			min_average_noise = average_noise[i];
1018 			min_average_noise_antenna_i = i;
1019 		}
1020 	}
1021 
1022 	IWL_DEBUG_CALIB(priv, "average_noise: a %d b %d c %d\n",
1023 			average_noise[0], average_noise[1],
1024 			average_noise[2]);
1025 
1026 	IWL_DEBUG_CALIB(priv, "min_average_noise = %d, antenna %d\n",
1027 			min_average_noise, min_average_noise_antenna_i);
1028 
1029 	iwlagn_gain_computation(
1030 		priv, average_noise,
1031 		find_first_chain(priv->nvm_data->valid_rx_ant));
1032 
1033 	/* Some power changes may have been made during the calibration.
1034 	 * Update and commit the RXON
1035 	 */
1036 	iwl_update_chain_flags(priv);
1037 
1038 	data->state = IWL_CHAIN_NOISE_DONE;
1039 	iwl_power_update_mode(priv, false);
1040 }
1041 
1042 void iwl_reset_run_time_calib(struct iwl_priv *priv)
1043 {
1044 	int i;
1045 	memset(&(priv->sensitivity_data), 0,
1046 	       sizeof(struct iwl_sensitivity_data));
1047 	memset(&(priv->chain_noise_data), 0,
1048 	       sizeof(struct iwl_chain_noise_data));
1049 	for (i = 0; i < NUM_RX_CHAINS; i++)
1050 		priv->chain_noise_data.delta_gain_code[i] =
1051 				CHAIN_NOISE_DELTA_GAIN_INIT_VAL;
1052 
1053 	/* Ask for statistics now, the uCode will send notification
1054 	 * periodically after association */
1055 	iwl_send_statistics_request(priv, CMD_ASYNC, true);
1056 }
1057