xref: /linux/drivers/net/wireless/intel/iwlwifi/dvm/calib.c (revision 6fdcba32711044c35c0e1b094cbd8f3f0b4472c9)
1 /******************************************************************************
2  *
3  * This file is provided under a dual BSD/GPLv2 license.  When using or
4  * redistributing this file, you may do so under either license.
5  *
6  * GPL LICENSE SUMMARY
7  *
8  * Copyright(c) 2008 - 2014 Intel Corporation. All rights reserved.
9  *
10  * This program is free software; you can redistribute it and/or modify
11  * it under the terms of version 2 of the GNU General Public License as
12  * published by the Free Software Foundation.
13  *
14  * This program is distributed in the hope that it will be useful, but
15  * WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * The full GNU General Public License is included in this distribution
20  * in the file called COPYING.
21  *
22  * Contact Information:
23  *  Intel Linux Wireless <linuxwifi@intel.com>
24  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
25  *
26  * BSD LICENSE
27  *
28  * Copyright(c) 2005 - 2014 Intel Corporation. All rights reserved.
29  * All rights reserved.
30  *
31  * Redistribution and use in source and binary forms, with or without
32  * modification, are permitted provided that the following conditions
33  * are met:
34  *
35  *  * Redistributions of source code must retain the above copyright
36  *    notice, this list of conditions and the following disclaimer.
37  *  * Redistributions in binary form must reproduce the above copyright
38  *    notice, this list of conditions and the following disclaimer in
39  *    the documentation and/or other materials provided with the
40  *    distribution.
41  *  * Neither the name Intel Corporation nor the names of its
42  *    contributors may be used to endorse or promote products derived
43  *    from this software without specific prior written permission.
44  *
45  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
46  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
47  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
48  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
49  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
50  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
51  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
52  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
53  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
54  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
55  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
56  *****************************************************************************/
57 
58 #include <linux/slab.h>
59 #include <net/mac80211.h>
60 
61 #include "iwl-trans.h"
62 
63 #include "dev.h"
64 #include "calib.h"
65 #include "agn.h"
66 
67 /*****************************************************************************
68  * INIT calibrations framework
69  *****************************************************************************/
70 
71 /* Opaque calibration results */
72 struct iwl_calib_result {
73 	struct list_head list;
74 	size_t cmd_len;
75 	struct iwl_calib_hdr hdr;
76 	/* data follows */
77 };
78 
79 struct statistics_general_data {
80 	u32 beacon_silence_rssi_a;
81 	u32 beacon_silence_rssi_b;
82 	u32 beacon_silence_rssi_c;
83 	u32 beacon_energy_a;
84 	u32 beacon_energy_b;
85 	u32 beacon_energy_c;
86 };
87 
88 int iwl_send_calib_results(struct iwl_priv *priv)
89 {
90 	struct iwl_host_cmd hcmd = {
91 		.id = REPLY_PHY_CALIBRATION_CMD,
92 	};
93 	struct iwl_calib_result *res;
94 
95 	list_for_each_entry(res, &priv->calib_results, list) {
96 		int ret;
97 
98 		hcmd.len[0] = res->cmd_len;
99 		hcmd.data[0] = &res->hdr;
100 		hcmd.dataflags[0] = IWL_HCMD_DFL_NOCOPY;
101 		ret = iwl_dvm_send_cmd(priv, &hcmd);
102 		if (ret) {
103 			IWL_ERR(priv, "Error %d on calib cmd %d\n",
104 				ret, res->hdr.op_code);
105 			return ret;
106 		}
107 	}
108 
109 	return 0;
110 }
111 
112 int iwl_calib_set(struct iwl_priv *priv,
113 		  const struct iwl_calib_hdr *cmd, int len)
114 {
115 	struct iwl_calib_result *res, *tmp;
116 
117 	res = kmalloc(sizeof(*res) + len - sizeof(struct iwl_calib_hdr),
118 		      GFP_ATOMIC);
119 	if (!res)
120 		return -ENOMEM;
121 	memcpy(&res->hdr, cmd, len);
122 	res->cmd_len = len;
123 
124 	list_for_each_entry(tmp, &priv->calib_results, list) {
125 		if (tmp->hdr.op_code == res->hdr.op_code) {
126 			list_replace(&tmp->list, &res->list);
127 			kfree(tmp);
128 			return 0;
129 		}
130 	}
131 
132 	/* wasn't in list already */
133 	list_add_tail(&res->list, &priv->calib_results);
134 
135 	return 0;
136 }
137 
138 void iwl_calib_free_results(struct iwl_priv *priv)
139 {
140 	struct iwl_calib_result *res, *tmp;
141 
142 	list_for_each_entry_safe(res, tmp, &priv->calib_results, list) {
143 		list_del(&res->list);
144 		kfree(res);
145 	}
146 }
147 
148 /*****************************************************************************
149  * RUNTIME calibrations framework
150  *****************************************************************************/
151 
152 /* "false alarms" are signals that our DSP tries to lock onto,
153  *   but then determines that they are either noise, or transmissions
154  *   from a distant wireless network (also "noise", really) that get
155  *   "stepped on" by stronger transmissions within our own network.
156  * This algorithm attempts to set a sensitivity level that is high
157  *   enough to receive all of our own network traffic, but not so
158  *   high that our DSP gets too busy trying to lock onto non-network
159  *   activity/noise. */
160 static int iwl_sens_energy_cck(struct iwl_priv *priv,
161 				   u32 norm_fa,
162 				   u32 rx_enable_time,
163 				   struct statistics_general_data *rx_info)
164 {
165 	u32 max_nrg_cck = 0;
166 	int i = 0;
167 	u8 max_silence_rssi = 0;
168 	u32 silence_ref = 0;
169 	u8 silence_rssi_a = 0;
170 	u8 silence_rssi_b = 0;
171 	u8 silence_rssi_c = 0;
172 	u32 val;
173 
174 	/* "false_alarms" values below are cross-multiplications to assess the
175 	 *   numbers of false alarms within the measured period of actual Rx
176 	 *   (Rx is off when we're txing), vs the min/max expected false alarms
177 	 *   (some should be expected if rx is sensitive enough) in a
178 	 *   hypothetical listening period of 200 time units (TU), 204.8 msec:
179 	 *
180 	 * MIN_FA/fixed-time < false_alarms/actual-rx-time < MAX_FA/beacon-time
181 	 *
182 	 * */
183 	u32 false_alarms = norm_fa * 200 * 1024;
184 	u32 max_false_alarms = MAX_FA_CCK * rx_enable_time;
185 	u32 min_false_alarms = MIN_FA_CCK * rx_enable_time;
186 	struct iwl_sensitivity_data *data = NULL;
187 	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
188 
189 	data = &(priv->sensitivity_data);
190 
191 	data->nrg_auto_corr_silence_diff = 0;
192 
193 	/* Find max silence rssi among all 3 receivers.
194 	 * This is background noise, which may include transmissions from other
195 	 *    networks, measured during silence before our network's beacon */
196 	silence_rssi_a = (u8)((rx_info->beacon_silence_rssi_a &
197 			    ALL_BAND_FILTER) >> 8);
198 	silence_rssi_b = (u8)((rx_info->beacon_silence_rssi_b &
199 			    ALL_BAND_FILTER) >> 8);
200 	silence_rssi_c = (u8)((rx_info->beacon_silence_rssi_c &
201 			    ALL_BAND_FILTER) >> 8);
202 
203 	val = max(silence_rssi_b, silence_rssi_c);
204 	max_silence_rssi = max(silence_rssi_a, (u8) val);
205 
206 	/* Store silence rssi in 20-beacon history table */
207 	data->nrg_silence_rssi[data->nrg_silence_idx] = max_silence_rssi;
208 	data->nrg_silence_idx++;
209 	if (data->nrg_silence_idx >= NRG_NUM_PREV_STAT_L)
210 		data->nrg_silence_idx = 0;
211 
212 	/* Find max silence rssi across 20 beacon history */
213 	for (i = 0; i < NRG_NUM_PREV_STAT_L; i++) {
214 		val = data->nrg_silence_rssi[i];
215 		silence_ref = max(silence_ref, val);
216 	}
217 	IWL_DEBUG_CALIB(priv, "silence a %u, b %u, c %u, 20-bcn max %u\n",
218 			silence_rssi_a, silence_rssi_b, silence_rssi_c,
219 			silence_ref);
220 
221 	/* Find max rx energy (min value!) among all 3 receivers,
222 	 *   measured during beacon frame.
223 	 * Save it in 10-beacon history table. */
224 	i = data->nrg_energy_idx;
225 	val = min(rx_info->beacon_energy_b, rx_info->beacon_energy_c);
226 	data->nrg_value[i] = min(rx_info->beacon_energy_a, val);
227 
228 	data->nrg_energy_idx++;
229 	if (data->nrg_energy_idx >= 10)
230 		data->nrg_energy_idx = 0;
231 
232 	/* Find min rx energy (max value) across 10 beacon history.
233 	 * This is the minimum signal level that we want to receive well.
234 	 * Add backoff (margin so we don't miss slightly lower energy frames).
235 	 * This establishes an upper bound (min value) for energy threshold. */
236 	max_nrg_cck = data->nrg_value[0];
237 	for (i = 1; i < 10; i++)
238 		max_nrg_cck = (u32) max(max_nrg_cck, (data->nrg_value[i]));
239 	max_nrg_cck += 6;
240 
241 	IWL_DEBUG_CALIB(priv, "rx energy a %u, b %u, c %u, 10-bcn max/min %u\n",
242 			rx_info->beacon_energy_a, rx_info->beacon_energy_b,
243 			rx_info->beacon_energy_c, max_nrg_cck - 6);
244 
245 	/* Count number of consecutive beacons with fewer-than-desired
246 	 *   false alarms. */
247 	if (false_alarms < min_false_alarms)
248 		data->num_in_cck_no_fa++;
249 	else
250 		data->num_in_cck_no_fa = 0;
251 	IWL_DEBUG_CALIB(priv, "consecutive bcns with few false alarms = %u\n",
252 			data->num_in_cck_no_fa);
253 
254 	/* If we got too many false alarms this time, reduce sensitivity */
255 	if ((false_alarms > max_false_alarms) &&
256 		(data->auto_corr_cck > AUTO_CORR_MAX_TH_CCK)) {
257 		IWL_DEBUG_CALIB(priv, "norm FA %u > max FA %u\n",
258 		     false_alarms, max_false_alarms);
259 		IWL_DEBUG_CALIB(priv, "... reducing sensitivity\n");
260 		data->nrg_curr_state = IWL_FA_TOO_MANY;
261 		/* Store for "fewer than desired" on later beacon */
262 		data->nrg_silence_ref = silence_ref;
263 
264 		/* increase energy threshold (reduce nrg value)
265 		 *   to decrease sensitivity */
266 		data->nrg_th_cck = data->nrg_th_cck - NRG_STEP_CCK;
267 	/* Else if we got fewer than desired, increase sensitivity */
268 	} else if (false_alarms < min_false_alarms) {
269 		data->nrg_curr_state = IWL_FA_TOO_FEW;
270 
271 		/* Compare silence level with silence level for most recent
272 		 *   healthy number or too many false alarms */
273 		data->nrg_auto_corr_silence_diff = (s32)data->nrg_silence_ref -
274 						   (s32)silence_ref;
275 
276 		IWL_DEBUG_CALIB(priv, "norm FA %u < min FA %u, silence diff %d\n",
277 			 false_alarms, min_false_alarms,
278 			 data->nrg_auto_corr_silence_diff);
279 
280 		/* Increase value to increase sensitivity, but only if:
281 		 * 1a) previous beacon did *not* have *too many* false alarms
282 		 * 1b) AND there's a significant difference in Rx levels
283 		 *      from a previous beacon with too many, or healthy # FAs
284 		 * OR 2) We've seen a lot of beacons (100) with too few
285 		 *       false alarms */
286 		if ((data->nrg_prev_state != IWL_FA_TOO_MANY) &&
287 			((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
288 			(data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {
289 
290 			IWL_DEBUG_CALIB(priv, "... increasing sensitivity\n");
291 			/* Increase nrg value to increase sensitivity */
292 			val = data->nrg_th_cck + NRG_STEP_CCK;
293 			data->nrg_th_cck = min((u32)ranges->min_nrg_cck, val);
294 		} else {
295 			IWL_DEBUG_CALIB(priv, "... but not changing sensitivity\n");
296 		}
297 
298 	/* Else we got a healthy number of false alarms, keep status quo */
299 	} else {
300 		IWL_DEBUG_CALIB(priv, " FA in safe zone\n");
301 		data->nrg_curr_state = IWL_FA_GOOD_RANGE;
302 
303 		/* Store for use in "fewer than desired" with later beacon */
304 		data->nrg_silence_ref = silence_ref;
305 
306 		/* If previous beacon had too many false alarms,
307 		 *   give it some extra margin by reducing sensitivity again
308 		 *   (but don't go below measured energy of desired Rx) */
309 		if (data->nrg_prev_state == IWL_FA_TOO_MANY) {
310 			IWL_DEBUG_CALIB(priv, "... increasing margin\n");
311 			if (data->nrg_th_cck > (max_nrg_cck + NRG_MARGIN))
312 				data->nrg_th_cck -= NRG_MARGIN;
313 			else
314 				data->nrg_th_cck = max_nrg_cck;
315 		}
316 	}
317 
318 	/* Make sure the energy threshold does not go above the measured
319 	 * energy of the desired Rx signals (reduced by backoff margin),
320 	 * or else we might start missing Rx frames.
321 	 * Lower value is higher energy, so we use max()!
322 	 */
323 	data->nrg_th_cck = max(max_nrg_cck, data->nrg_th_cck);
324 	IWL_DEBUG_CALIB(priv, "new nrg_th_cck %u\n", data->nrg_th_cck);
325 
326 	data->nrg_prev_state = data->nrg_curr_state;
327 
328 	/* Auto-correlation CCK algorithm */
329 	if (false_alarms > min_false_alarms) {
330 
331 		/* increase auto_corr values to decrease sensitivity
332 		 * so the DSP won't be disturbed by the noise
333 		 */
334 		if (data->auto_corr_cck < AUTO_CORR_MAX_TH_CCK)
335 			data->auto_corr_cck = AUTO_CORR_MAX_TH_CCK + 1;
336 		else {
337 			val = data->auto_corr_cck + AUTO_CORR_STEP_CCK;
338 			data->auto_corr_cck =
339 				min((u32)ranges->auto_corr_max_cck, val);
340 		}
341 		val = data->auto_corr_cck_mrc + AUTO_CORR_STEP_CCK;
342 		data->auto_corr_cck_mrc =
343 			min((u32)ranges->auto_corr_max_cck_mrc, val);
344 	} else if ((false_alarms < min_false_alarms) &&
345 	   ((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
346 	   (data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {
347 
348 		/* Decrease auto_corr values to increase sensitivity */
349 		val = data->auto_corr_cck - AUTO_CORR_STEP_CCK;
350 		data->auto_corr_cck =
351 			max((u32)ranges->auto_corr_min_cck, val);
352 		val = data->auto_corr_cck_mrc - AUTO_CORR_STEP_CCK;
353 		data->auto_corr_cck_mrc =
354 			max((u32)ranges->auto_corr_min_cck_mrc, val);
355 	}
356 
357 	return 0;
358 }
359 
360 
361 static int iwl_sens_auto_corr_ofdm(struct iwl_priv *priv,
362 				       u32 norm_fa,
363 				       u32 rx_enable_time)
364 {
365 	u32 val;
366 	u32 false_alarms = norm_fa * 200 * 1024;
367 	u32 max_false_alarms = MAX_FA_OFDM * rx_enable_time;
368 	u32 min_false_alarms = MIN_FA_OFDM * rx_enable_time;
369 	struct iwl_sensitivity_data *data = NULL;
370 	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
371 
372 	data = &(priv->sensitivity_data);
373 
374 	/* If we got too many false alarms this time, reduce sensitivity */
375 	if (false_alarms > max_false_alarms) {
376 
377 		IWL_DEBUG_CALIB(priv, "norm FA %u > max FA %u)\n",
378 			     false_alarms, max_false_alarms);
379 
380 		val = data->auto_corr_ofdm + AUTO_CORR_STEP_OFDM;
381 		data->auto_corr_ofdm =
382 			min((u32)ranges->auto_corr_max_ofdm, val);
383 
384 		val = data->auto_corr_ofdm_mrc + AUTO_CORR_STEP_OFDM;
385 		data->auto_corr_ofdm_mrc =
386 			min((u32)ranges->auto_corr_max_ofdm_mrc, val);
387 
388 		val = data->auto_corr_ofdm_x1 + AUTO_CORR_STEP_OFDM;
389 		data->auto_corr_ofdm_x1 =
390 			min((u32)ranges->auto_corr_max_ofdm_x1, val);
391 
392 		val = data->auto_corr_ofdm_mrc_x1 + AUTO_CORR_STEP_OFDM;
393 		data->auto_corr_ofdm_mrc_x1 =
394 			min((u32)ranges->auto_corr_max_ofdm_mrc_x1, val);
395 	}
396 
397 	/* Else if we got fewer than desired, increase sensitivity */
398 	else if (false_alarms < min_false_alarms) {
399 
400 		IWL_DEBUG_CALIB(priv, "norm FA %u < min FA %u\n",
401 			     false_alarms, min_false_alarms);
402 
403 		val = data->auto_corr_ofdm - AUTO_CORR_STEP_OFDM;
404 		data->auto_corr_ofdm =
405 			max((u32)ranges->auto_corr_min_ofdm, val);
406 
407 		val = data->auto_corr_ofdm_mrc - AUTO_CORR_STEP_OFDM;
408 		data->auto_corr_ofdm_mrc =
409 			max((u32)ranges->auto_corr_min_ofdm_mrc, val);
410 
411 		val = data->auto_corr_ofdm_x1 - AUTO_CORR_STEP_OFDM;
412 		data->auto_corr_ofdm_x1 =
413 			max((u32)ranges->auto_corr_min_ofdm_x1, val);
414 
415 		val = data->auto_corr_ofdm_mrc_x1 - AUTO_CORR_STEP_OFDM;
416 		data->auto_corr_ofdm_mrc_x1 =
417 			max((u32)ranges->auto_corr_min_ofdm_mrc_x1, val);
418 	} else {
419 		IWL_DEBUG_CALIB(priv, "min FA %u < norm FA %u < max FA %u OK\n",
420 			 min_false_alarms, false_alarms, max_false_alarms);
421 	}
422 	return 0;
423 }
424 
425 static void iwl_prepare_legacy_sensitivity_tbl(struct iwl_priv *priv,
426 				struct iwl_sensitivity_data *data,
427 				__le16 *tbl)
428 {
429 	tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_INDEX] =
430 				cpu_to_le16((u16)data->auto_corr_ofdm);
431 	tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_MRC_INDEX] =
432 				cpu_to_le16((u16)data->auto_corr_ofdm_mrc);
433 	tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_INDEX] =
434 				cpu_to_le16((u16)data->auto_corr_ofdm_x1);
435 	tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_MRC_INDEX] =
436 				cpu_to_le16((u16)data->auto_corr_ofdm_mrc_x1);
437 
438 	tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_INDEX] =
439 				cpu_to_le16((u16)data->auto_corr_cck);
440 	tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_MRC_INDEX] =
441 				cpu_to_le16((u16)data->auto_corr_cck_mrc);
442 
443 	tbl[HD_MIN_ENERGY_CCK_DET_INDEX] =
444 				cpu_to_le16((u16)data->nrg_th_cck);
445 	tbl[HD_MIN_ENERGY_OFDM_DET_INDEX] =
446 				cpu_to_le16((u16)data->nrg_th_ofdm);
447 
448 	tbl[HD_BARKER_CORR_TH_ADD_MIN_INDEX] =
449 				cpu_to_le16(data->barker_corr_th_min);
450 	tbl[HD_BARKER_CORR_TH_ADD_MIN_MRC_INDEX] =
451 				cpu_to_le16(data->barker_corr_th_min_mrc);
452 	tbl[HD_OFDM_ENERGY_TH_IN_INDEX] =
453 				cpu_to_le16(data->nrg_th_cca);
454 
455 	IWL_DEBUG_CALIB(priv, "ofdm: ac %u mrc %u x1 %u mrc_x1 %u thresh %u\n",
456 			data->auto_corr_ofdm, data->auto_corr_ofdm_mrc,
457 			data->auto_corr_ofdm_x1, data->auto_corr_ofdm_mrc_x1,
458 			data->nrg_th_ofdm);
459 
460 	IWL_DEBUG_CALIB(priv, "cck: ac %u mrc %u thresh %u\n",
461 			data->auto_corr_cck, data->auto_corr_cck_mrc,
462 			data->nrg_th_cck);
463 }
464 
465 /* Prepare a SENSITIVITY_CMD, send to uCode if values have changed */
466 static int iwl_sensitivity_write(struct iwl_priv *priv)
467 {
468 	struct iwl_sensitivity_cmd cmd;
469 	struct iwl_sensitivity_data *data = NULL;
470 	struct iwl_host_cmd cmd_out = {
471 		.id = SENSITIVITY_CMD,
472 		.len = { sizeof(struct iwl_sensitivity_cmd), },
473 		.flags = CMD_ASYNC,
474 		.data = { &cmd, },
475 	};
476 
477 	data = &(priv->sensitivity_data);
478 
479 	memset(&cmd, 0, sizeof(cmd));
480 
481 	iwl_prepare_legacy_sensitivity_tbl(priv, data, &cmd.table[0]);
482 
483 	/* Update uCode's "work" table, and copy it to DSP */
484 	cmd.control = SENSITIVITY_CMD_CONTROL_WORK_TABLE;
485 
486 	/* Don't send command to uCode if nothing has changed */
487 	if (!memcmp(&cmd.table[0], &(priv->sensitivity_tbl[0]),
488 		    sizeof(u16)*HD_TABLE_SIZE)) {
489 		IWL_DEBUG_CALIB(priv, "No change in SENSITIVITY_CMD\n");
490 		return 0;
491 	}
492 
493 	/* Copy table for comparison next time */
494 	memcpy(&(priv->sensitivity_tbl[0]), &(cmd.table[0]),
495 	       sizeof(u16)*HD_TABLE_SIZE);
496 
497 	return iwl_dvm_send_cmd(priv, &cmd_out);
498 }
499 
500 /* Prepare a SENSITIVITY_CMD, send to uCode if values have changed */
501 static int iwl_enhance_sensitivity_write(struct iwl_priv *priv)
502 {
503 	struct iwl_enhance_sensitivity_cmd cmd;
504 	struct iwl_sensitivity_data *data = NULL;
505 	struct iwl_host_cmd cmd_out = {
506 		.id = SENSITIVITY_CMD,
507 		.len = { sizeof(struct iwl_enhance_sensitivity_cmd), },
508 		.flags = CMD_ASYNC,
509 		.data = { &cmd, },
510 	};
511 
512 	data = &(priv->sensitivity_data);
513 
514 	memset(&cmd, 0, sizeof(cmd));
515 
516 	iwl_prepare_legacy_sensitivity_tbl(priv, data, &cmd.enhance_table[0]);
517 
518 	if (priv->lib->hd_v2) {
519 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX] =
520 			HD_INA_NON_SQUARE_DET_OFDM_DATA_V2;
521 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_CCK_INDEX] =
522 			HD_INA_NON_SQUARE_DET_CCK_DATA_V2;
523 		cmd.enhance_table[HD_CORR_11_INSTEAD_OF_CORR_9_EN_INDEX] =
524 			HD_CORR_11_INSTEAD_OF_CORR_9_EN_DATA_V2;
525 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
526 			HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_DATA_V2;
527 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
528 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V2;
529 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_INDEX] =
530 			HD_OFDM_NON_SQUARE_DET_SLOPE_DATA_V2;
531 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_INDEX] =
532 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_DATA_V2;
533 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
534 			HD_CCK_NON_SQUARE_DET_SLOPE_MRC_DATA_V2;
535 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
536 			HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V2;
537 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_INDEX] =
538 			HD_CCK_NON_SQUARE_DET_SLOPE_DATA_V2;
539 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_INDEX] =
540 			HD_CCK_NON_SQUARE_DET_INTERCEPT_DATA_V2;
541 	} else {
542 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX] =
543 			HD_INA_NON_SQUARE_DET_OFDM_DATA_V1;
544 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_CCK_INDEX] =
545 			HD_INA_NON_SQUARE_DET_CCK_DATA_V1;
546 		cmd.enhance_table[HD_CORR_11_INSTEAD_OF_CORR_9_EN_INDEX] =
547 			HD_CORR_11_INSTEAD_OF_CORR_9_EN_DATA_V1;
548 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
549 			HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_DATA_V1;
550 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
551 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V1;
552 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_INDEX] =
553 			HD_OFDM_NON_SQUARE_DET_SLOPE_DATA_V1;
554 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_INDEX] =
555 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_DATA_V1;
556 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
557 			HD_CCK_NON_SQUARE_DET_SLOPE_MRC_DATA_V1;
558 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
559 			HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V1;
560 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_INDEX] =
561 			HD_CCK_NON_SQUARE_DET_SLOPE_DATA_V1;
562 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_INDEX] =
563 			HD_CCK_NON_SQUARE_DET_INTERCEPT_DATA_V1;
564 	}
565 
566 	/* Update uCode's "work" table, and copy it to DSP */
567 	cmd.control = SENSITIVITY_CMD_CONTROL_WORK_TABLE;
568 
569 	/* Don't send command to uCode if nothing has changed */
570 	if (!memcmp(&cmd.enhance_table[0], &(priv->sensitivity_tbl[0]),
571 		    sizeof(u16)*HD_TABLE_SIZE) &&
572 	    !memcmp(&cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX],
573 		    &(priv->enhance_sensitivity_tbl[0]),
574 		    sizeof(u16)*ENHANCE_HD_TABLE_ENTRIES)) {
575 		IWL_DEBUG_CALIB(priv, "No change in SENSITIVITY_CMD\n");
576 		return 0;
577 	}
578 
579 	/* Copy table for comparison next time */
580 	memcpy(&(priv->sensitivity_tbl[0]), &(cmd.enhance_table[0]),
581 	       sizeof(u16)*HD_TABLE_SIZE);
582 	memcpy(&(priv->enhance_sensitivity_tbl[0]),
583 	       &(cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX]),
584 	       sizeof(u16)*ENHANCE_HD_TABLE_ENTRIES);
585 
586 	return iwl_dvm_send_cmd(priv, &cmd_out);
587 }
588 
589 void iwl_init_sensitivity(struct iwl_priv *priv)
590 {
591 	int ret = 0;
592 	int i;
593 	struct iwl_sensitivity_data *data = NULL;
594 	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
595 
596 	if (priv->calib_disabled & IWL_SENSITIVITY_CALIB_DISABLED)
597 		return;
598 
599 	IWL_DEBUG_CALIB(priv, "Start iwl_init_sensitivity\n");
600 
601 	/* Clear driver's sensitivity algo data */
602 	data = &(priv->sensitivity_data);
603 
604 	if (ranges == NULL)
605 		return;
606 
607 	memset(data, 0, sizeof(struct iwl_sensitivity_data));
608 
609 	data->num_in_cck_no_fa = 0;
610 	data->nrg_curr_state = IWL_FA_TOO_MANY;
611 	data->nrg_prev_state = IWL_FA_TOO_MANY;
612 	data->nrg_silence_ref = 0;
613 	data->nrg_silence_idx = 0;
614 	data->nrg_energy_idx = 0;
615 
616 	for (i = 0; i < 10; i++)
617 		data->nrg_value[i] = 0;
618 
619 	for (i = 0; i < NRG_NUM_PREV_STAT_L; i++)
620 		data->nrg_silence_rssi[i] = 0;
621 
622 	data->auto_corr_ofdm =  ranges->auto_corr_min_ofdm;
623 	data->auto_corr_ofdm_mrc = ranges->auto_corr_min_ofdm_mrc;
624 	data->auto_corr_ofdm_x1  = ranges->auto_corr_min_ofdm_x1;
625 	data->auto_corr_ofdm_mrc_x1 = ranges->auto_corr_min_ofdm_mrc_x1;
626 	data->auto_corr_cck = AUTO_CORR_CCK_MIN_VAL_DEF;
627 	data->auto_corr_cck_mrc = ranges->auto_corr_min_cck_mrc;
628 	data->nrg_th_cck = ranges->nrg_th_cck;
629 	data->nrg_th_ofdm = ranges->nrg_th_ofdm;
630 	data->barker_corr_th_min = ranges->barker_corr_th_min;
631 	data->barker_corr_th_min_mrc = ranges->barker_corr_th_min_mrc;
632 	data->nrg_th_cca = ranges->nrg_th_cca;
633 
634 	data->last_bad_plcp_cnt_ofdm = 0;
635 	data->last_fa_cnt_ofdm = 0;
636 	data->last_bad_plcp_cnt_cck = 0;
637 	data->last_fa_cnt_cck = 0;
638 
639 	if (priv->fw->enhance_sensitivity_table)
640 		ret |= iwl_enhance_sensitivity_write(priv);
641 	else
642 		ret |= iwl_sensitivity_write(priv);
643 	IWL_DEBUG_CALIB(priv, "<<return 0x%X\n", ret);
644 }
645 
646 void iwl_sensitivity_calibration(struct iwl_priv *priv)
647 {
648 	u32 rx_enable_time;
649 	u32 fa_cck;
650 	u32 fa_ofdm;
651 	u32 bad_plcp_cck;
652 	u32 bad_plcp_ofdm;
653 	u32 norm_fa_ofdm;
654 	u32 norm_fa_cck;
655 	struct iwl_sensitivity_data *data = NULL;
656 	struct statistics_rx_non_phy *rx_info;
657 	struct statistics_rx_phy *ofdm, *cck;
658 	struct statistics_general_data statis;
659 
660 	if (priv->calib_disabled & IWL_SENSITIVITY_CALIB_DISABLED)
661 		return;
662 
663 	data = &(priv->sensitivity_data);
664 
665 	if (!iwl_is_any_associated(priv)) {
666 		IWL_DEBUG_CALIB(priv, "<< - not associated\n");
667 		return;
668 	}
669 
670 	spin_lock_bh(&priv->statistics.lock);
671 	rx_info = &priv->statistics.rx_non_phy;
672 	ofdm = &priv->statistics.rx_ofdm;
673 	cck = &priv->statistics.rx_cck;
674 	if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
675 		IWL_DEBUG_CALIB(priv, "<< invalid data.\n");
676 		spin_unlock_bh(&priv->statistics.lock);
677 		return;
678 	}
679 
680 	/* Extract Statistics: */
681 	rx_enable_time = le32_to_cpu(rx_info->channel_load);
682 	fa_cck = le32_to_cpu(cck->false_alarm_cnt);
683 	fa_ofdm = le32_to_cpu(ofdm->false_alarm_cnt);
684 	bad_plcp_cck = le32_to_cpu(cck->plcp_err);
685 	bad_plcp_ofdm = le32_to_cpu(ofdm->plcp_err);
686 
687 	statis.beacon_silence_rssi_a =
688 			le32_to_cpu(rx_info->beacon_silence_rssi_a);
689 	statis.beacon_silence_rssi_b =
690 			le32_to_cpu(rx_info->beacon_silence_rssi_b);
691 	statis.beacon_silence_rssi_c =
692 			le32_to_cpu(rx_info->beacon_silence_rssi_c);
693 	statis.beacon_energy_a =
694 			le32_to_cpu(rx_info->beacon_energy_a);
695 	statis.beacon_energy_b =
696 			le32_to_cpu(rx_info->beacon_energy_b);
697 	statis.beacon_energy_c =
698 			le32_to_cpu(rx_info->beacon_energy_c);
699 
700 	spin_unlock_bh(&priv->statistics.lock);
701 
702 	IWL_DEBUG_CALIB(priv, "rx_enable_time = %u usecs\n", rx_enable_time);
703 
704 	if (!rx_enable_time) {
705 		IWL_DEBUG_CALIB(priv, "<< RX Enable Time == 0!\n");
706 		return;
707 	}
708 
709 	/* These statistics increase monotonically, and do not reset
710 	 *   at each beacon.  Calculate difference from last value, or just
711 	 *   use the new statistics value if it has reset or wrapped around. */
712 	if (data->last_bad_plcp_cnt_cck > bad_plcp_cck)
713 		data->last_bad_plcp_cnt_cck = bad_plcp_cck;
714 	else {
715 		bad_plcp_cck -= data->last_bad_plcp_cnt_cck;
716 		data->last_bad_plcp_cnt_cck += bad_plcp_cck;
717 	}
718 
719 	if (data->last_bad_plcp_cnt_ofdm > bad_plcp_ofdm)
720 		data->last_bad_plcp_cnt_ofdm = bad_plcp_ofdm;
721 	else {
722 		bad_plcp_ofdm -= data->last_bad_plcp_cnt_ofdm;
723 		data->last_bad_plcp_cnt_ofdm += bad_plcp_ofdm;
724 	}
725 
726 	if (data->last_fa_cnt_ofdm > fa_ofdm)
727 		data->last_fa_cnt_ofdm = fa_ofdm;
728 	else {
729 		fa_ofdm -= data->last_fa_cnt_ofdm;
730 		data->last_fa_cnt_ofdm += fa_ofdm;
731 	}
732 
733 	if (data->last_fa_cnt_cck > fa_cck)
734 		data->last_fa_cnt_cck = fa_cck;
735 	else {
736 		fa_cck -= data->last_fa_cnt_cck;
737 		data->last_fa_cnt_cck += fa_cck;
738 	}
739 
740 	/* Total aborted signal locks */
741 	norm_fa_ofdm = fa_ofdm + bad_plcp_ofdm;
742 	norm_fa_cck = fa_cck + bad_plcp_cck;
743 
744 	IWL_DEBUG_CALIB(priv, "cck: fa %u badp %u  ofdm: fa %u badp %u\n", fa_cck,
745 			bad_plcp_cck, fa_ofdm, bad_plcp_ofdm);
746 
747 	iwl_sens_auto_corr_ofdm(priv, norm_fa_ofdm, rx_enable_time);
748 	iwl_sens_energy_cck(priv, norm_fa_cck, rx_enable_time, &statis);
749 	if (priv->fw->enhance_sensitivity_table)
750 		iwl_enhance_sensitivity_write(priv);
751 	else
752 		iwl_sensitivity_write(priv);
753 }
754 
755 static inline u8 find_first_chain(u8 mask)
756 {
757 	if (mask & ANT_A)
758 		return CHAIN_A;
759 	if (mask & ANT_B)
760 		return CHAIN_B;
761 	return CHAIN_C;
762 }
763 
764 /**
765  * Run disconnected antenna algorithm to find out which antennas are
766  * disconnected.
767  */
768 static void iwl_find_disconn_antenna(struct iwl_priv *priv, u32* average_sig,
769 				     struct iwl_chain_noise_data *data)
770 {
771 	u32 active_chains = 0;
772 	u32 max_average_sig;
773 	u16 max_average_sig_antenna_i;
774 	u8 num_tx_chains;
775 	u8 first_chain;
776 	u16 i = 0;
777 
778 	average_sig[0] = data->chain_signal_a / IWL_CAL_NUM_BEACONS;
779 	average_sig[1] = data->chain_signal_b / IWL_CAL_NUM_BEACONS;
780 	average_sig[2] = data->chain_signal_c / IWL_CAL_NUM_BEACONS;
781 
782 	if (average_sig[0] >= average_sig[1]) {
783 		max_average_sig = average_sig[0];
784 		max_average_sig_antenna_i = 0;
785 		active_chains = (1 << max_average_sig_antenna_i);
786 	} else {
787 		max_average_sig = average_sig[1];
788 		max_average_sig_antenna_i = 1;
789 		active_chains = (1 << max_average_sig_antenna_i);
790 	}
791 
792 	if (average_sig[2] >= max_average_sig) {
793 		max_average_sig = average_sig[2];
794 		max_average_sig_antenna_i = 2;
795 		active_chains = (1 << max_average_sig_antenna_i);
796 	}
797 
798 	IWL_DEBUG_CALIB(priv, "average_sig: a %d b %d c %d\n",
799 		     average_sig[0], average_sig[1], average_sig[2]);
800 	IWL_DEBUG_CALIB(priv, "max_average_sig = %d, antenna %d\n",
801 		     max_average_sig, max_average_sig_antenna_i);
802 
803 	/* Compare signal strengths for all 3 receivers. */
804 	for (i = 0; i < NUM_RX_CHAINS; i++) {
805 		if (i != max_average_sig_antenna_i) {
806 			s32 rssi_delta = (max_average_sig - average_sig[i]);
807 
808 			/* If signal is very weak, compared with
809 			 * strongest, mark it as disconnected. */
810 			if (rssi_delta > MAXIMUM_ALLOWED_PATHLOSS)
811 				data->disconn_array[i] = 1;
812 			else
813 				active_chains |= (1 << i);
814 			IWL_DEBUG_CALIB(priv, "i = %d  rssiDelta = %d  "
815 			     "disconn_array[i] = %d\n",
816 			     i, rssi_delta, data->disconn_array[i]);
817 		}
818 	}
819 
820 	/*
821 	 * The above algorithm sometimes fails when the ucode
822 	 * reports 0 for all chains. It's not clear why that
823 	 * happens to start with, but it is then causing trouble
824 	 * because this can make us enable more chains than the
825 	 * hardware really has.
826 	 *
827 	 * To be safe, simply mask out any chains that we know
828 	 * are not on the device.
829 	 */
830 	active_chains &= priv->nvm_data->valid_rx_ant;
831 
832 	num_tx_chains = 0;
833 	for (i = 0; i < NUM_RX_CHAINS; i++) {
834 		/* loops on all the bits of
835 		 * priv->hw_setting.valid_tx_ant */
836 		u8 ant_msk = (1 << i);
837 		if (!(priv->nvm_data->valid_tx_ant & ant_msk))
838 			continue;
839 
840 		num_tx_chains++;
841 		if (data->disconn_array[i] == 0)
842 			/* there is a Tx antenna connected */
843 			break;
844 		if (num_tx_chains == priv->hw_params.tx_chains_num &&
845 		    data->disconn_array[i]) {
846 			/*
847 			 * If all chains are disconnected
848 			 * connect the first valid tx chain
849 			 */
850 			first_chain =
851 				find_first_chain(priv->nvm_data->valid_tx_ant);
852 			data->disconn_array[first_chain] = 0;
853 			active_chains |= BIT(first_chain);
854 			IWL_DEBUG_CALIB(priv,
855 					"All Tx chains are disconnected W/A - declare %d as connected\n",
856 					first_chain);
857 			break;
858 		}
859 	}
860 
861 	if (active_chains != priv->nvm_data->valid_rx_ant &&
862 	    active_chains != priv->chain_noise_data.active_chains)
863 		IWL_DEBUG_CALIB(priv,
864 				"Detected that not all antennas are connected! "
865 				"Connected: %#x, valid: %#x.\n",
866 				active_chains,
867 				priv->nvm_data->valid_rx_ant);
868 
869 	/* Save for use within RXON, TX, SCAN commands, etc. */
870 	data->active_chains = active_chains;
871 	IWL_DEBUG_CALIB(priv, "active_chains (bitwise) = 0x%x\n",
872 			active_chains);
873 }
874 
875 static void iwlagn_gain_computation(struct iwl_priv *priv,
876 				    u32 average_noise[NUM_RX_CHAINS],
877 				    u8 default_chain)
878 {
879 	int i;
880 	s32 delta_g;
881 	struct iwl_chain_noise_data *data = &priv->chain_noise_data;
882 
883 	/*
884 	 * Find Gain Code for the chains based on "default chain"
885 	 */
886 	for (i = default_chain + 1; i < NUM_RX_CHAINS; i++) {
887 		if ((data->disconn_array[i])) {
888 			data->delta_gain_code[i] = 0;
889 			continue;
890 		}
891 
892 		delta_g = (priv->lib->chain_noise_scale *
893 			((s32)average_noise[default_chain] -
894 			(s32)average_noise[i])) / 1500;
895 
896 		/* bound gain by 2 bits value max, 3rd bit is sign */
897 		data->delta_gain_code[i] =
898 			min(abs(delta_g), CHAIN_NOISE_MAX_DELTA_GAIN_CODE);
899 
900 		if (delta_g < 0)
901 			/*
902 			 * set negative sign ...
903 			 * note to Intel developers:  This is uCode API format,
904 			 *   not the format of any internal device registers.
905 			 *   Do not change this format for e.g. 6050 or similar
906 			 *   devices.  Change format only if more resolution
907 			 *   (i.e. more than 2 bits magnitude) is needed.
908 			 */
909 			data->delta_gain_code[i] |= (1 << 2);
910 	}
911 
912 	IWL_DEBUG_CALIB(priv, "Delta gains: ANT_B = %d  ANT_C = %d\n",
913 			data->delta_gain_code[1], data->delta_gain_code[2]);
914 
915 	if (!data->radio_write) {
916 		struct iwl_calib_chain_noise_gain_cmd cmd;
917 
918 		memset(&cmd, 0, sizeof(cmd));
919 
920 		iwl_set_calib_hdr(&cmd.hdr,
921 			priv->phy_calib_chain_noise_gain_cmd);
922 		cmd.delta_gain_1 = data->delta_gain_code[1];
923 		cmd.delta_gain_2 = data->delta_gain_code[2];
924 		iwl_dvm_send_cmd_pdu(priv, REPLY_PHY_CALIBRATION_CMD,
925 			CMD_ASYNC, sizeof(cmd), &cmd);
926 
927 		data->radio_write = 1;
928 		data->state = IWL_CHAIN_NOISE_CALIBRATED;
929 	}
930 }
931 
932 /*
933  * Accumulate 16 beacons of signal and noise statistics for each of
934  *   3 receivers/antennas/rx-chains, then figure out:
935  * 1)  Which antennas are connected.
936  * 2)  Differential rx gain settings to balance the 3 receivers.
937  */
938 void iwl_chain_noise_calibration(struct iwl_priv *priv)
939 {
940 	struct iwl_chain_noise_data *data = NULL;
941 
942 	u32 chain_noise_a;
943 	u32 chain_noise_b;
944 	u32 chain_noise_c;
945 	u32 chain_sig_a;
946 	u32 chain_sig_b;
947 	u32 chain_sig_c;
948 	u32 average_sig[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
949 	u32 average_noise[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
950 	u32 min_average_noise = MIN_AVERAGE_NOISE_MAX_VALUE;
951 	u16 min_average_noise_antenna_i = INITIALIZATION_VALUE;
952 	u16 i = 0;
953 	u16 rxon_chnum = INITIALIZATION_VALUE;
954 	u16 stat_chnum = INITIALIZATION_VALUE;
955 	u8 rxon_band24;
956 	u8 stat_band24;
957 	struct statistics_rx_non_phy *rx_info;
958 
959 	/*
960 	 * MULTI-FIXME:
961 	 * When we support multiple interfaces on different channels,
962 	 * this must be modified/fixed.
963 	 */
964 	struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
965 
966 	if (priv->calib_disabled & IWL_CHAIN_NOISE_CALIB_DISABLED)
967 		return;
968 
969 	data = &(priv->chain_noise_data);
970 
971 	/*
972 	 * Accumulate just the first "chain_noise_num_beacons" after
973 	 * the first association, then we're done forever.
974 	 */
975 	if (data->state != IWL_CHAIN_NOISE_ACCUMULATE) {
976 		if (data->state == IWL_CHAIN_NOISE_ALIVE)
977 			IWL_DEBUG_CALIB(priv, "Wait for noise calib reset\n");
978 		return;
979 	}
980 
981 	spin_lock_bh(&priv->statistics.lock);
982 
983 	rx_info = &priv->statistics.rx_non_phy;
984 
985 	if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
986 		IWL_DEBUG_CALIB(priv, " << Interference data unavailable\n");
987 		spin_unlock_bh(&priv->statistics.lock);
988 		return;
989 	}
990 
991 	rxon_band24 = !!(ctx->staging.flags & RXON_FLG_BAND_24G_MSK);
992 	rxon_chnum = le16_to_cpu(ctx->staging.channel);
993 	stat_band24 =
994 		!!(priv->statistics.flag & STATISTICS_REPLY_FLG_BAND_24G_MSK);
995 	stat_chnum = le32_to_cpu(priv->statistics.flag) >> 16;
996 
997 	/* Make sure we accumulate data for just the associated channel
998 	 *   (even if scanning). */
999 	if ((rxon_chnum != stat_chnum) || (rxon_band24 != stat_band24)) {
1000 		IWL_DEBUG_CALIB(priv, "Stats not from chan=%d, band24=%d\n",
1001 				rxon_chnum, rxon_band24);
1002 		spin_unlock_bh(&priv->statistics.lock);
1003 		return;
1004 	}
1005 
1006 	/*
1007 	 *  Accumulate beacon statistics values across
1008 	 * "chain_noise_num_beacons"
1009 	 */
1010 	chain_noise_a = le32_to_cpu(rx_info->beacon_silence_rssi_a) &
1011 				IN_BAND_FILTER;
1012 	chain_noise_b = le32_to_cpu(rx_info->beacon_silence_rssi_b) &
1013 				IN_BAND_FILTER;
1014 	chain_noise_c = le32_to_cpu(rx_info->beacon_silence_rssi_c) &
1015 				IN_BAND_FILTER;
1016 
1017 	chain_sig_a = le32_to_cpu(rx_info->beacon_rssi_a) & IN_BAND_FILTER;
1018 	chain_sig_b = le32_to_cpu(rx_info->beacon_rssi_b) & IN_BAND_FILTER;
1019 	chain_sig_c = le32_to_cpu(rx_info->beacon_rssi_c) & IN_BAND_FILTER;
1020 
1021 	spin_unlock_bh(&priv->statistics.lock);
1022 
1023 	data->beacon_count++;
1024 
1025 	data->chain_noise_a = (chain_noise_a + data->chain_noise_a);
1026 	data->chain_noise_b = (chain_noise_b + data->chain_noise_b);
1027 	data->chain_noise_c = (chain_noise_c + data->chain_noise_c);
1028 
1029 	data->chain_signal_a = (chain_sig_a + data->chain_signal_a);
1030 	data->chain_signal_b = (chain_sig_b + data->chain_signal_b);
1031 	data->chain_signal_c = (chain_sig_c + data->chain_signal_c);
1032 
1033 	IWL_DEBUG_CALIB(priv, "chan=%d, band24=%d, beacon=%d\n",
1034 			rxon_chnum, rxon_band24, data->beacon_count);
1035 	IWL_DEBUG_CALIB(priv, "chain_sig: a %d b %d c %d\n",
1036 			chain_sig_a, chain_sig_b, chain_sig_c);
1037 	IWL_DEBUG_CALIB(priv, "chain_noise: a %d b %d c %d\n",
1038 			chain_noise_a, chain_noise_b, chain_noise_c);
1039 
1040 	/* If this is the "chain_noise_num_beacons", determine:
1041 	 * 1)  Disconnected antennas (using signal strengths)
1042 	 * 2)  Differential gain (using silence noise) to balance receivers */
1043 	if (data->beacon_count != IWL_CAL_NUM_BEACONS)
1044 		return;
1045 
1046 	/* Analyze signal for disconnected antenna */
1047 	if (priv->lib->bt_params &&
1048 	    priv->lib->bt_params->advanced_bt_coexist) {
1049 		/* Disable disconnected antenna algorithm for advanced
1050 		   bt coex, assuming valid antennas are connected */
1051 		data->active_chains = priv->nvm_data->valid_rx_ant;
1052 		for (i = 0; i < NUM_RX_CHAINS; i++)
1053 			if (!(data->active_chains & (1<<i)))
1054 				data->disconn_array[i] = 1;
1055 	} else
1056 		iwl_find_disconn_antenna(priv, average_sig, data);
1057 
1058 	/* Analyze noise for rx balance */
1059 	average_noise[0] = data->chain_noise_a / IWL_CAL_NUM_BEACONS;
1060 	average_noise[1] = data->chain_noise_b / IWL_CAL_NUM_BEACONS;
1061 	average_noise[2] = data->chain_noise_c / IWL_CAL_NUM_BEACONS;
1062 
1063 	for (i = 0; i < NUM_RX_CHAINS; i++) {
1064 		if (!(data->disconn_array[i]) &&
1065 		   (average_noise[i] <= min_average_noise)) {
1066 			/* This means that chain i is active and has
1067 			 * lower noise values so far: */
1068 			min_average_noise = average_noise[i];
1069 			min_average_noise_antenna_i = i;
1070 		}
1071 	}
1072 
1073 	IWL_DEBUG_CALIB(priv, "average_noise: a %d b %d c %d\n",
1074 			average_noise[0], average_noise[1],
1075 			average_noise[2]);
1076 
1077 	IWL_DEBUG_CALIB(priv, "min_average_noise = %d, antenna %d\n",
1078 			min_average_noise, min_average_noise_antenna_i);
1079 
1080 	iwlagn_gain_computation(
1081 		priv, average_noise,
1082 		find_first_chain(priv->nvm_data->valid_rx_ant));
1083 
1084 	/* Some power changes may have been made during the calibration.
1085 	 * Update and commit the RXON
1086 	 */
1087 	iwl_update_chain_flags(priv);
1088 
1089 	data->state = IWL_CHAIN_NOISE_DONE;
1090 	iwl_power_update_mode(priv, false);
1091 }
1092 
1093 void iwl_reset_run_time_calib(struct iwl_priv *priv)
1094 {
1095 	int i;
1096 	memset(&(priv->sensitivity_data), 0,
1097 	       sizeof(struct iwl_sensitivity_data));
1098 	memset(&(priv->chain_noise_data), 0,
1099 	       sizeof(struct iwl_chain_noise_data));
1100 	for (i = 0; i < NUM_RX_CHAINS; i++)
1101 		priv->chain_noise_data.delta_gain_code[i] =
1102 				CHAIN_NOISE_DELTA_GAIN_INIT_VAL;
1103 
1104 	/* Ask for statistics now, the uCode will send notification
1105 	 * periodically after association */
1106 	iwl_send_statistics_request(priv, CMD_ASYNC, true);
1107 }
1108