xref: /linux/drivers/net/wireless/intel/iwlwifi/dvm/calib.c (revision e58e871becec2d3b04ed91c0c16fe8deac9c9dfa)
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  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, write to the Free Software
21  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
22  * USA
23  *
24  * The full GNU General Public License is included in this distribution
25  * in the file called COPYING.
26  *
27  * Contact Information:
28  *  Intel Linux Wireless <linuxwifi@intel.com>
29  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
30  *
31  * BSD LICENSE
32  *
33  * Copyright(c) 2005 - 2014 Intel Corporation. All rights reserved.
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37  * modification, are permitted provided that the following conditions
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41  *    notice, this list of conditions and the following disclaimer.
42  *  * Redistributions in binary form must reproduce the above copyright
43  *    notice, this list of conditions and the following disclaimer in
44  *    the documentation and/or other materials provided with the
45  *    distribution.
46  *  * Neither the name Intel Corporation nor the names of its
47  *    contributors may be used to endorse or promote products derived
48  *    from this software without specific prior written permission.
49  *
50  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
51  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
52  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
53  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
54  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
55  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
56  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
57  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
58  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
59  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
60  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
61  *****************************************************************************/
62 
63 #include <linux/slab.h>
64 #include <net/mac80211.h>
65 
66 #include "iwl-trans.h"
67 
68 #include "dev.h"
69 #include "calib.h"
70 #include "agn.h"
71 
72 /*****************************************************************************
73  * INIT calibrations framework
74  *****************************************************************************/
75 
76 /* Opaque calibration results */
77 struct iwl_calib_result {
78 	struct list_head list;
79 	size_t cmd_len;
80 	struct iwl_calib_hdr hdr;
81 	/* data follows */
82 };
83 
84 struct statistics_general_data {
85 	u32 beacon_silence_rssi_a;
86 	u32 beacon_silence_rssi_b;
87 	u32 beacon_silence_rssi_c;
88 	u32 beacon_energy_a;
89 	u32 beacon_energy_b;
90 	u32 beacon_energy_c;
91 };
92 
93 int iwl_send_calib_results(struct iwl_priv *priv)
94 {
95 	struct iwl_host_cmd hcmd = {
96 		.id = REPLY_PHY_CALIBRATION_CMD,
97 	};
98 	struct iwl_calib_result *res;
99 
100 	list_for_each_entry(res, &priv->calib_results, list) {
101 		int ret;
102 
103 		hcmd.len[0] = res->cmd_len;
104 		hcmd.data[0] = &res->hdr;
105 		hcmd.dataflags[0] = IWL_HCMD_DFL_NOCOPY;
106 		ret = iwl_dvm_send_cmd(priv, &hcmd);
107 		if (ret) {
108 			IWL_ERR(priv, "Error %d on calib cmd %d\n",
109 				ret, res->hdr.op_code);
110 			return ret;
111 		}
112 	}
113 
114 	return 0;
115 }
116 
117 int iwl_calib_set(struct iwl_priv *priv,
118 		  const struct iwl_calib_hdr *cmd, int len)
119 {
120 	struct iwl_calib_result *res, *tmp;
121 
122 	res = kmalloc(sizeof(*res) + len - sizeof(struct iwl_calib_hdr),
123 		      GFP_ATOMIC);
124 	if (!res)
125 		return -ENOMEM;
126 	memcpy(&res->hdr, cmd, len);
127 	res->cmd_len = len;
128 
129 	list_for_each_entry(tmp, &priv->calib_results, list) {
130 		if (tmp->hdr.op_code == res->hdr.op_code) {
131 			list_replace(&tmp->list, &res->list);
132 			kfree(tmp);
133 			return 0;
134 		}
135 	}
136 
137 	/* wasn't in list already */
138 	list_add_tail(&res->list, &priv->calib_results);
139 
140 	return 0;
141 }
142 
143 void iwl_calib_free_results(struct iwl_priv *priv)
144 {
145 	struct iwl_calib_result *res, *tmp;
146 
147 	list_for_each_entry_safe(res, tmp, &priv->calib_results, list) {
148 		list_del(&res->list);
149 		kfree(res);
150 	}
151 }
152 
153 /*****************************************************************************
154  * RUNTIME calibrations framework
155  *****************************************************************************/
156 
157 /* "false alarms" are signals that our DSP tries to lock onto,
158  *   but then determines that they are either noise, or transmissions
159  *   from a distant wireless network (also "noise", really) that get
160  *   "stepped on" by stronger transmissions within our own network.
161  * This algorithm attempts to set a sensitivity level that is high
162  *   enough to receive all of our own network traffic, but not so
163  *   high that our DSP gets too busy trying to lock onto non-network
164  *   activity/noise. */
165 static int iwl_sens_energy_cck(struct iwl_priv *priv,
166 				   u32 norm_fa,
167 				   u32 rx_enable_time,
168 				   struct statistics_general_data *rx_info)
169 {
170 	u32 max_nrg_cck = 0;
171 	int i = 0;
172 	u8 max_silence_rssi = 0;
173 	u32 silence_ref = 0;
174 	u8 silence_rssi_a = 0;
175 	u8 silence_rssi_b = 0;
176 	u8 silence_rssi_c = 0;
177 	u32 val;
178 
179 	/* "false_alarms" values below are cross-multiplications to assess the
180 	 *   numbers of false alarms within the measured period of actual Rx
181 	 *   (Rx is off when we're txing), vs the min/max expected false alarms
182 	 *   (some should be expected if rx is sensitive enough) in a
183 	 *   hypothetical listening period of 200 time units (TU), 204.8 msec:
184 	 *
185 	 * MIN_FA/fixed-time < false_alarms/actual-rx-time < MAX_FA/beacon-time
186 	 *
187 	 * */
188 	u32 false_alarms = norm_fa * 200 * 1024;
189 	u32 max_false_alarms = MAX_FA_CCK * rx_enable_time;
190 	u32 min_false_alarms = MIN_FA_CCK * rx_enable_time;
191 	struct iwl_sensitivity_data *data = NULL;
192 	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
193 
194 	data = &(priv->sensitivity_data);
195 
196 	data->nrg_auto_corr_silence_diff = 0;
197 
198 	/* Find max silence rssi among all 3 receivers.
199 	 * This is background noise, which may include transmissions from other
200 	 *    networks, measured during silence before our network's beacon */
201 	silence_rssi_a = (u8)((rx_info->beacon_silence_rssi_a &
202 			    ALL_BAND_FILTER) >> 8);
203 	silence_rssi_b = (u8)((rx_info->beacon_silence_rssi_b &
204 			    ALL_BAND_FILTER) >> 8);
205 	silence_rssi_c = (u8)((rx_info->beacon_silence_rssi_c &
206 			    ALL_BAND_FILTER) >> 8);
207 
208 	val = max(silence_rssi_b, silence_rssi_c);
209 	max_silence_rssi = max(silence_rssi_a, (u8) val);
210 
211 	/* Store silence rssi in 20-beacon history table */
212 	data->nrg_silence_rssi[data->nrg_silence_idx] = max_silence_rssi;
213 	data->nrg_silence_idx++;
214 	if (data->nrg_silence_idx >= NRG_NUM_PREV_STAT_L)
215 		data->nrg_silence_idx = 0;
216 
217 	/* Find max silence rssi across 20 beacon history */
218 	for (i = 0; i < NRG_NUM_PREV_STAT_L; i++) {
219 		val = data->nrg_silence_rssi[i];
220 		silence_ref = max(silence_ref, val);
221 	}
222 	IWL_DEBUG_CALIB(priv, "silence a %u, b %u, c %u, 20-bcn max %u\n",
223 			silence_rssi_a, silence_rssi_b, silence_rssi_c,
224 			silence_ref);
225 
226 	/* Find max rx energy (min value!) among all 3 receivers,
227 	 *   measured during beacon frame.
228 	 * Save it in 10-beacon history table. */
229 	i = data->nrg_energy_idx;
230 	val = min(rx_info->beacon_energy_b, rx_info->beacon_energy_c);
231 	data->nrg_value[i] = min(rx_info->beacon_energy_a, val);
232 
233 	data->nrg_energy_idx++;
234 	if (data->nrg_energy_idx >= 10)
235 		data->nrg_energy_idx = 0;
236 
237 	/* Find min rx energy (max value) across 10 beacon history.
238 	 * This is the minimum signal level that we want to receive well.
239 	 * Add backoff (margin so we don't miss slightly lower energy frames).
240 	 * This establishes an upper bound (min value) for energy threshold. */
241 	max_nrg_cck = data->nrg_value[0];
242 	for (i = 1; i < 10; i++)
243 		max_nrg_cck = (u32) max(max_nrg_cck, (data->nrg_value[i]));
244 	max_nrg_cck += 6;
245 
246 	IWL_DEBUG_CALIB(priv, "rx energy a %u, b %u, c %u, 10-bcn max/min %u\n",
247 			rx_info->beacon_energy_a, rx_info->beacon_energy_b,
248 			rx_info->beacon_energy_c, max_nrg_cck - 6);
249 
250 	/* Count number of consecutive beacons with fewer-than-desired
251 	 *   false alarms. */
252 	if (false_alarms < min_false_alarms)
253 		data->num_in_cck_no_fa++;
254 	else
255 		data->num_in_cck_no_fa = 0;
256 	IWL_DEBUG_CALIB(priv, "consecutive bcns with few false alarms = %u\n",
257 			data->num_in_cck_no_fa);
258 
259 	/* If we got too many false alarms this time, reduce sensitivity */
260 	if ((false_alarms > max_false_alarms) &&
261 		(data->auto_corr_cck > AUTO_CORR_MAX_TH_CCK)) {
262 		IWL_DEBUG_CALIB(priv, "norm FA %u > max FA %u\n",
263 		     false_alarms, max_false_alarms);
264 		IWL_DEBUG_CALIB(priv, "... reducing sensitivity\n");
265 		data->nrg_curr_state = IWL_FA_TOO_MANY;
266 		/* Store for "fewer than desired" on later beacon */
267 		data->nrg_silence_ref = silence_ref;
268 
269 		/* increase energy threshold (reduce nrg value)
270 		 *   to decrease sensitivity */
271 		data->nrg_th_cck = data->nrg_th_cck - NRG_STEP_CCK;
272 	/* Else if we got fewer than desired, increase sensitivity */
273 	} else if (false_alarms < min_false_alarms) {
274 		data->nrg_curr_state = IWL_FA_TOO_FEW;
275 
276 		/* Compare silence level with silence level for most recent
277 		 *   healthy number or too many false alarms */
278 		data->nrg_auto_corr_silence_diff = (s32)data->nrg_silence_ref -
279 						   (s32)silence_ref;
280 
281 		IWL_DEBUG_CALIB(priv, "norm FA %u < min FA %u, silence diff %d\n",
282 			 false_alarms, min_false_alarms,
283 			 data->nrg_auto_corr_silence_diff);
284 
285 		/* Increase value to increase sensitivity, but only if:
286 		 * 1a) previous beacon did *not* have *too many* false alarms
287 		 * 1b) AND there's a significant difference in Rx levels
288 		 *      from a previous beacon with too many, or healthy # FAs
289 		 * OR 2) We've seen a lot of beacons (100) with too few
290 		 *       false alarms */
291 		if ((data->nrg_prev_state != IWL_FA_TOO_MANY) &&
292 			((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
293 			(data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {
294 
295 			IWL_DEBUG_CALIB(priv, "... increasing sensitivity\n");
296 			/* Increase nrg value to increase sensitivity */
297 			val = data->nrg_th_cck + NRG_STEP_CCK;
298 			data->nrg_th_cck = min((u32)ranges->min_nrg_cck, val);
299 		} else {
300 			IWL_DEBUG_CALIB(priv, "... but not changing sensitivity\n");
301 		}
302 
303 	/* Else we got a healthy number of false alarms, keep status quo */
304 	} else {
305 		IWL_DEBUG_CALIB(priv, " FA in safe zone\n");
306 		data->nrg_curr_state = IWL_FA_GOOD_RANGE;
307 
308 		/* Store for use in "fewer than desired" with later beacon */
309 		data->nrg_silence_ref = silence_ref;
310 
311 		/* If previous beacon had too many false alarms,
312 		 *   give it some extra margin by reducing sensitivity again
313 		 *   (but don't go below measured energy of desired Rx) */
314 		if (data->nrg_prev_state == IWL_FA_TOO_MANY) {
315 			IWL_DEBUG_CALIB(priv, "... increasing margin\n");
316 			if (data->nrg_th_cck > (max_nrg_cck + NRG_MARGIN))
317 				data->nrg_th_cck -= NRG_MARGIN;
318 			else
319 				data->nrg_th_cck = max_nrg_cck;
320 		}
321 	}
322 
323 	/* Make sure the energy threshold does not go above the measured
324 	 * energy of the desired Rx signals (reduced by backoff margin),
325 	 * or else we might start missing Rx frames.
326 	 * Lower value is higher energy, so we use max()!
327 	 */
328 	data->nrg_th_cck = max(max_nrg_cck, data->nrg_th_cck);
329 	IWL_DEBUG_CALIB(priv, "new nrg_th_cck %u\n", data->nrg_th_cck);
330 
331 	data->nrg_prev_state = data->nrg_curr_state;
332 
333 	/* Auto-correlation CCK algorithm */
334 	if (false_alarms > min_false_alarms) {
335 
336 		/* increase auto_corr values to decrease sensitivity
337 		 * so the DSP won't be disturbed by the noise
338 		 */
339 		if (data->auto_corr_cck < AUTO_CORR_MAX_TH_CCK)
340 			data->auto_corr_cck = AUTO_CORR_MAX_TH_CCK + 1;
341 		else {
342 			val = data->auto_corr_cck + AUTO_CORR_STEP_CCK;
343 			data->auto_corr_cck =
344 				min((u32)ranges->auto_corr_max_cck, val);
345 		}
346 		val = data->auto_corr_cck_mrc + AUTO_CORR_STEP_CCK;
347 		data->auto_corr_cck_mrc =
348 			min((u32)ranges->auto_corr_max_cck_mrc, val);
349 	} else if ((false_alarms < min_false_alarms) &&
350 	   ((data->nrg_auto_corr_silence_diff > NRG_DIFF) ||
351 	   (data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA))) {
352 
353 		/* Decrease auto_corr values to increase sensitivity */
354 		val = data->auto_corr_cck - AUTO_CORR_STEP_CCK;
355 		data->auto_corr_cck =
356 			max((u32)ranges->auto_corr_min_cck, val);
357 		val = data->auto_corr_cck_mrc - AUTO_CORR_STEP_CCK;
358 		data->auto_corr_cck_mrc =
359 			max((u32)ranges->auto_corr_min_cck_mrc, val);
360 	}
361 
362 	return 0;
363 }
364 
365 
366 static int iwl_sens_auto_corr_ofdm(struct iwl_priv *priv,
367 				       u32 norm_fa,
368 				       u32 rx_enable_time)
369 {
370 	u32 val;
371 	u32 false_alarms = norm_fa * 200 * 1024;
372 	u32 max_false_alarms = MAX_FA_OFDM * rx_enable_time;
373 	u32 min_false_alarms = MIN_FA_OFDM * rx_enable_time;
374 	struct iwl_sensitivity_data *data = NULL;
375 	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
376 
377 	data = &(priv->sensitivity_data);
378 
379 	/* If we got too many false alarms this time, reduce sensitivity */
380 	if (false_alarms > max_false_alarms) {
381 
382 		IWL_DEBUG_CALIB(priv, "norm FA %u > max FA %u)\n",
383 			     false_alarms, max_false_alarms);
384 
385 		val = data->auto_corr_ofdm + AUTO_CORR_STEP_OFDM;
386 		data->auto_corr_ofdm =
387 			min((u32)ranges->auto_corr_max_ofdm, val);
388 
389 		val = data->auto_corr_ofdm_mrc + AUTO_CORR_STEP_OFDM;
390 		data->auto_corr_ofdm_mrc =
391 			min((u32)ranges->auto_corr_max_ofdm_mrc, val);
392 
393 		val = data->auto_corr_ofdm_x1 + AUTO_CORR_STEP_OFDM;
394 		data->auto_corr_ofdm_x1 =
395 			min((u32)ranges->auto_corr_max_ofdm_x1, val);
396 
397 		val = data->auto_corr_ofdm_mrc_x1 + AUTO_CORR_STEP_OFDM;
398 		data->auto_corr_ofdm_mrc_x1 =
399 			min((u32)ranges->auto_corr_max_ofdm_mrc_x1, val);
400 	}
401 
402 	/* Else if we got fewer than desired, increase sensitivity */
403 	else if (false_alarms < min_false_alarms) {
404 
405 		IWL_DEBUG_CALIB(priv, "norm FA %u < min FA %u\n",
406 			     false_alarms, min_false_alarms);
407 
408 		val = data->auto_corr_ofdm - AUTO_CORR_STEP_OFDM;
409 		data->auto_corr_ofdm =
410 			max((u32)ranges->auto_corr_min_ofdm, val);
411 
412 		val = data->auto_corr_ofdm_mrc - AUTO_CORR_STEP_OFDM;
413 		data->auto_corr_ofdm_mrc =
414 			max((u32)ranges->auto_corr_min_ofdm_mrc, val);
415 
416 		val = data->auto_corr_ofdm_x1 - AUTO_CORR_STEP_OFDM;
417 		data->auto_corr_ofdm_x1 =
418 			max((u32)ranges->auto_corr_min_ofdm_x1, val);
419 
420 		val = data->auto_corr_ofdm_mrc_x1 - AUTO_CORR_STEP_OFDM;
421 		data->auto_corr_ofdm_mrc_x1 =
422 			max((u32)ranges->auto_corr_min_ofdm_mrc_x1, val);
423 	} else {
424 		IWL_DEBUG_CALIB(priv, "min FA %u < norm FA %u < max FA %u OK\n",
425 			 min_false_alarms, false_alarms, max_false_alarms);
426 	}
427 	return 0;
428 }
429 
430 static void iwl_prepare_legacy_sensitivity_tbl(struct iwl_priv *priv,
431 				struct iwl_sensitivity_data *data,
432 				__le16 *tbl)
433 {
434 	tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_INDEX] =
435 				cpu_to_le16((u16)data->auto_corr_ofdm);
436 	tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_MRC_INDEX] =
437 				cpu_to_le16((u16)data->auto_corr_ofdm_mrc);
438 	tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_INDEX] =
439 				cpu_to_le16((u16)data->auto_corr_ofdm_x1);
440 	tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_MRC_INDEX] =
441 				cpu_to_le16((u16)data->auto_corr_ofdm_mrc_x1);
442 
443 	tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_INDEX] =
444 				cpu_to_le16((u16)data->auto_corr_cck);
445 	tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_MRC_INDEX] =
446 				cpu_to_le16((u16)data->auto_corr_cck_mrc);
447 
448 	tbl[HD_MIN_ENERGY_CCK_DET_INDEX] =
449 				cpu_to_le16((u16)data->nrg_th_cck);
450 	tbl[HD_MIN_ENERGY_OFDM_DET_INDEX] =
451 				cpu_to_le16((u16)data->nrg_th_ofdm);
452 
453 	tbl[HD_BARKER_CORR_TH_ADD_MIN_INDEX] =
454 				cpu_to_le16(data->barker_corr_th_min);
455 	tbl[HD_BARKER_CORR_TH_ADD_MIN_MRC_INDEX] =
456 				cpu_to_le16(data->barker_corr_th_min_mrc);
457 	tbl[HD_OFDM_ENERGY_TH_IN_INDEX] =
458 				cpu_to_le16(data->nrg_th_cca);
459 
460 	IWL_DEBUG_CALIB(priv, "ofdm: ac %u mrc %u x1 %u mrc_x1 %u thresh %u\n",
461 			data->auto_corr_ofdm, data->auto_corr_ofdm_mrc,
462 			data->auto_corr_ofdm_x1, data->auto_corr_ofdm_mrc_x1,
463 			data->nrg_th_ofdm);
464 
465 	IWL_DEBUG_CALIB(priv, "cck: ac %u mrc %u thresh %u\n",
466 			data->auto_corr_cck, data->auto_corr_cck_mrc,
467 			data->nrg_th_cck);
468 }
469 
470 /* Prepare a SENSITIVITY_CMD, send to uCode if values have changed */
471 static int iwl_sensitivity_write(struct iwl_priv *priv)
472 {
473 	struct iwl_sensitivity_cmd cmd;
474 	struct iwl_sensitivity_data *data = NULL;
475 	struct iwl_host_cmd cmd_out = {
476 		.id = SENSITIVITY_CMD,
477 		.len = { sizeof(struct iwl_sensitivity_cmd), },
478 		.flags = CMD_ASYNC,
479 		.data = { &cmd, },
480 	};
481 
482 	data = &(priv->sensitivity_data);
483 
484 	memset(&cmd, 0, sizeof(cmd));
485 
486 	iwl_prepare_legacy_sensitivity_tbl(priv, data, &cmd.table[0]);
487 
488 	/* Update uCode's "work" table, and copy it to DSP */
489 	cmd.control = SENSITIVITY_CMD_CONTROL_WORK_TABLE;
490 
491 	/* Don't send command to uCode if nothing has changed */
492 	if (!memcmp(&cmd.table[0], &(priv->sensitivity_tbl[0]),
493 		    sizeof(u16)*HD_TABLE_SIZE)) {
494 		IWL_DEBUG_CALIB(priv, "No change in SENSITIVITY_CMD\n");
495 		return 0;
496 	}
497 
498 	/* Copy table for comparison next time */
499 	memcpy(&(priv->sensitivity_tbl[0]), &(cmd.table[0]),
500 	       sizeof(u16)*HD_TABLE_SIZE);
501 
502 	return iwl_dvm_send_cmd(priv, &cmd_out);
503 }
504 
505 /* Prepare a SENSITIVITY_CMD, send to uCode if values have changed */
506 static int iwl_enhance_sensitivity_write(struct iwl_priv *priv)
507 {
508 	struct iwl_enhance_sensitivity_cmd cmd;
509 	struct iwl_sensitivity_data *data = NULL;
510 	struct iwl_host_cmd cmd_out = {
511 		.id = SENSITIVITY_CMD,
512 		.len = { sizeof(struct iwl_enhance_sensitivity_cmd), },
513 		.flags = CMD_ASYNC,
514 		.data = { &cmd, },
515 	};
516 
517 	data = &(priv->sensitivity_data);
518 
519 	memset(&cmd, 0, sizeof(cmd));
520 
521 	iwl_prepare_legacy_sensitivity_tbl(priv, data, &cmd.enhance_table[0]);
522 
523 	if (priv->lib->hd_v2) {
524 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX] =
525 			HD_INA_NON_SQUARE_DET_OFDM_DATA_V2;
526 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_CCK_INDEX] =
527 			HD_INA_NON_SQUARE_DET_CCK_DATA_V2;
528 		cmd.enhance_table[HD_CORR_11_INSTEAD_OF_CORR_9_EN_INDEX] =
529 			HD_CORR_11_INSTEAD_OF_CORR_9_EN_DATA_V2;
530 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
531 			HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_DATA_V2;
532 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
533 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V2;
534 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_INDEX] =
535 			HD_OFDM_NON_SQUARE_DET_SLOPE_DATA_V2;
536 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_INDEX] =
537 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_DATA_V2;
538 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
539 			HD_CCK_NON_SQUARE_DET_SLOPE_MRC_DATA_V2;
540 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
541 			HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V2;
542 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_INDEX] =
543 			HD_CCK_NON_SQUARE_DET_SLOPE_DATA_V2;
544 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_INDEX] =
545 			HD_CCK_NON_SQUARE_DET_INTERCEPT_DATA_V2;
546 	} else {
547 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX] =
548 			HD_INA_NON_SQUARE_DET_OFDM_DATA_V1;
549 		cmd.enhance_table[HD_INA_NON_SQUARE_DET_CCK_INDEX] =
550 			HD_INA_NON_SQUARE_DET_CCK_DATA_V1;
551 		cmd.enhance_table[HD_CORR_11_INSTEAD_OF_CORR_9_EN_INDEX] =
552 			HD_CORR_11_INSTEAD_OF_CORR_9_EN_DATA_V1;
553 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
554 			HD_OFDM_NON_SQUARE_DET_SLOPE_MRC_DATA_V1;
555 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
556 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V1;
557 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_SLOPE_INDEX] =
558 			HD_OFDM_NON_SQUARE_DET_SLOPE_DATA_V1;
559 		cmd.enhance_table[HD_OFDM_NON_SQUARE_DET_INTERCEPT_INDEX] =
560 			HD_OFDM_NON_SQUARE_DET_INTERCEPT_DATA_V1;
561 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_MRC_INDEX] =
562 			HD_CCK_NON_SQUARE_DET_SLOPE_MRC_DATA_V1;
563 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_INDEX] =
564 			HD_CCK_NON_SQUARE_DET_INTERCEPT_MRC_DATA_V1;
565 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_SLOPE_INDEX] =
566 			HD_CCK_NON_SQUARE_DET_SLOPE_DATA_V1;
567 		cmd.enhance_table[HD_CCK_NON_SQUARE_DET_INTERCEPT_INDEX] =
568 			HD_CCK_NON_SQUARE_DET_INTERCEPT_DATA_V1;
569 	}
570 
571 	/* Update uCode's "work" table, and copy it to DSP */
572 	cmd.control = SENSITIVITY_CMD_CONTROL_WORK_TABLE;
573 
574 	/* Don't send command to uCode if nothing has changed */
575 	if (!memcmp(&cmd.enhance_table[0], &(priv->sensitivity_tbl[0]),
576 		    sizeof(u16)*HD_TABLE_SIZE) &&
577 	    !memcmp(&cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX],
578 		    &(priv->enhance_sensitivity_tbl[0]),
579 		    sizeof(u16)*ENHANCE_HD_TABLE_ENTRIES)) {
580 		IWL_DEBUG_CALIB(priv, "No change in SENSITIVITY_CMD\n");
581 		return 0;
582 	}
583 
584 	/* Copy table for comparison next time */
585 	memcpy(&(priv->sensitivity_tbl[0]), &(cmd.enhance_table[0]),
586 	       sizeof(u16)*HD_TABLE_SIZE);
587 	memcpy(&(priv->enhance_sensitivity_tbl[0]),
588 	       &(cmd.enhance_table[HD_INA_NON_SQUARE_DET_OFDM_INDEX]),
589 	       sizeof(u16)*ENHANCE_HD_TABLE_ENTRIES);
590 
591 	return iwl_dvm_send_cmd(priv, &cmd_out);
592 }
593 
594 void iwl_init_sensitivity(struct iwl_priv *priv)
595 {
596 	int ret = 0;
597 	int i;
598 	struct iwl_sensitivity_data *data = NULL;
599 	const struct iwl_sensitivity_ranges *ranges = priv->hw_params.sens;
600 
601 	if (priv->calib_disabled & IWL_SENSITIVITY_CALIB_DISABLED)
602 		return;
603 
604 	IWL_DEBUG_CALIB(priv, "Start iwl_init_sensitivity\n");
605 
606 	/* Clear driver's sensitivity algo data */
607 	data = &(priv->sensitivity_data);
608 
609 	if (ranges == NULL)
610 		return;
611 
612 	memset(data, 0, sizeof(struct iwl_sensitivity_data));
613 
614 	data->num_in_cck_no_fa = 0;
615 	data->nrg_curr_state = IWL_FA_TOO_MANY;
616 	data->nrg_prev_state = IWL_FA_TOO_MANY;
617 	data->nrg_silence_ref = 0;
618 	data->nrg_silence_idx = 0;
619 	data->nrg_energy_idx = 0;
620 
621 	for (i = 0; i < 10; i++)
622 		data->nrg_value[i] = 0;
623 
624 	for (i = 0; i < NRG_NUM_PREV_STAT_L; i++)
625 		data->nrg_silence_rssi[i] = 0;
626 
627 	data->auto_corr_ofdm =  ranges->auto_corr_min_ofdm;
628 	data->auto_corr_ofdm_mrc = ranges->auto_corr_min_ofdm_mrc;
629 	data->auto_corr_ofdm_x1  = ranges->auto_corr_min_ofdm_x1;
630 	data->auto_corr_ofdm_mrc_x1 = ranges->auto_corr_min_ofdm_mrc_x1;
631 	data->auto_corr_cck = AUTO_CORR_CCK_MIN_VAL_DEF;
632 	data->auto_corr_cck_mrc = ranges->auto_corr_min_cck_mrc;
633 	data->nrg_th_cck = ranges->nrg_th_cck;
634 	data->nrg_th_ofdm = ranges->nrg_th_ofdm;
635 	data->barker_corr_th_min = ranges->barker_corr_th_min;
636 	data->barker_corr_th_min_mrc = ranges->barker_corr_th_min_mrc;
637 	data->nrg_th_cca = ranges->nrg_th_cca;
638 
639 	data->last_bad_plcp_cnt_ofdm = 0;
640 	data->last_fa_cnt_ofdm = 0;
641 	data->last_bad_plcp_cnt_cck = 0;
642 	data->last_fa_cnt_cck = 0;
643 
644 	if (priv->fw->enhance_sensitivity_table)
645 		ret |= iwl_enhance_sensitivity_write(priv);
646 	else
647 		ret |= iwl_sensitivity_write(priv);
648 	IWL_DEBUG_CALIB(priv, "<<return 0x%X\n", ret);
649 }
650 
651 void iwl_sensitivity_calibration(struct iwl_priv *priv)
652 {
653 	u32 rx_enable_time;
654 	u32 fa_cck;
655 	u32 fa_ofdm;
656 	u32 bad_plcp_cck;
657 	u32 bad_plcp_ofdm;
658 	u32 norm_fa_ofdm;
659 	u32 norm_fa_cck;
660 	struct iwl_sensitivity_data *data = NULL;
661 	struct statistics_rx_non_phy *rx_info;
662 	struct statistics_rx_phy *ofdm, *cck;
663 	struct statistics_general_data statis;
664 
665 	if (priv->calib_disabled & IWL_SENSITIVITY_CALIB_DISABLED)
666 		return;
667 
668 	data = &(priv->sensitivity_data);
669 
670 	if (!iwl_is_any_associated(priv)) {
671 		IWL_DEBUG_CALIB(priv, "<< - not associated\n");
672 		return;
673 	}
674 
675 	spin_lock_bh(&priv->statistics.lock);
676 	rx_info = &priv->statistics.rx_non_phy;
677 	ofdm = &priv->statistics.rx_ofdm;
678 	cck = &priv->statistics.rx_cck;
679 	if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
680 		IWL_DEBUG_CALIB(priv, "<< invalid data.\n");
681 		spin_unlock_bh(&priv->statistics.lock);
682 		return;
683 	}
684 
685 	/* Extract Statistics: */
686 	rx_enable_time = le32_to_cpu(rx_info->channel_load);
687 	fa_cck = le32_to_cpu(cck->false_alarm_cnt);
688 	fa_ofdm = le32_to_cpu(ofdm->false_alarm_cnt);
689 	bad_plcp_cck = le32_to_cpu(cck->plcp_err);
690 	bad_plcp_ofdm = le32_to_cpu(ofdm->plcp_err);
691 
692 	statis.beacon_silence_rssi_a =
693 			le32_to_cpu(rx_info->beacon_silence_rssi_a);
694 	statis.beacon_silence_rssi_b =
695 			le32_to_cpu(rx_info->beacon_silence_rssi_b);
696 	statis.beacon_silence_rssi_c =
697 			le32_to_cpu(rx_info->beacon_silence_rssi_c);
698 	statis.beacon_energy_a =
699 			le32_to_cpu(rx_info->beacon_energy_a);
700 	statis.beacon_energy_b =
701 			le32_to_cpu(rx_info->beacon_energy_b);
702 	statis.beacon_energy_c =
703 			le32_to_cpu(rx_info->beacon_energy_c);
704 
705 	spin_unlock_bh(&priv->statistics.lock);
706 
707 	IWL_DEBUG_CALIB(priv, "rx_enable_time = %u usecs\n", rx_enable_time);
708 
709 	if (!rx_enable_time) {
710 		IWL_DEBUG_CALIB(priv, "<< RX Enable Time == 0!\n");
711 		return;
712 	}
713 
714 	/* These statistics increase monotonically, and do not reset
715 	 *   at each beacon.  Calculate difference from last value, or just
716 	 *   use the new statistics value if it has reset or wrapped around. */
717 	if (data->last_bad_plcp_cnt_cck > bad_plcp_cck)
718 		data->last_bad_plcp_cnt_cck = bad_plcp_cck;
719 	else {
720 		bad_plcp_cck -= data->last_bad_plcp_cnt_cck;
721 		data->last_bad_plcp_cnt_cck += bad_plcp_cck;
722 	}
723 
724 	if (data->last_bad_plcp_cnt_ofdm > bad_plcp_ofdm)
725 		data->last_bad_plcp_cnt_ofdm = bad_plcp_ofdm;
726 	else {
727 		bad_plcp_ofdm -= data->last_bad_plcp_cnt_ofdm;
728 		data->last_bad_plcp_cnt_ofdm += bad_plcp_ofdm;
729 	}
730 
731 	if (data->last_fa_cnt_ofdm > fa_ofdm)
732 		data->last_fa_cnt_ofdm = fa_ofdm;
733 	else {
734 		fa_ofdm -= data->last_fa_cnt_ofdm;
735 		data->last_fa_cnt_ofdm += fa_ofdm;
736 	}
737 
738 	if (data->last_fa_cnt_cck > fa_cck)
739 		data->last_fa_cnt_cck = fa_cck;
740 	else {
741 		fa_cck -= data->last_fa_cnt_cck;
742 		data->last_fa_cnt_cck += fa_cck;
743 	}
744 
745 	/* Total aborted signal locks */
746 	norm_fa_ofdm = fa_ofdm + bad_plcp_ofdm;
747 	norm_fa_cck = fa_cck + bad_plcp_cck;
748 
749 	IWL_DEBUG_CALIB(priv, "cck: fa %u badp %u  ofdm: fa %u badp %u\n", fa_cck,
750 			bad_plcp_cck, fa_ofdm, bad_plcp_ofdm);
751 
752 	iwl_sens_auto_corr_ofdm(priv, norm_fa_ofdm, rx_enable_time);
753 	iwl_sens_energy_cck(priv, norm_fa_cck, rx_enable_time, &statis);
754 	if (priv->fw->enhance_sensitivity_table)
755 		iwl_enhance_sensitivity_write(priv);
756 	else
757 		iwl_sensitivity_write(priv);
758 }
759 
760 static inline u8 find_first_chain(u8 mask)
761 {
762 	if (mask & ANT_A)
763 		return CHAIN_A;
764 	if (mask & ANT_B)
765 		return CHAIN_B;
766 	return CHAIN_C;
767 }
768 
769 /**
770  * Run disconnected antenna algorithm to find out which antennas are
771  * disconnected.
772  */
773 static void iwl_find_disconn_antenna(struct iwl_priv *priv, u32* average_sig,
774 				     struct iwl_chain_noise_data *data)
775 {
776 	u32 active_chains = 0;
777 	u32 max_average_sig;
778 	u16 max_average_sig_antenna_i;
779 	u8 num_tx_chains;
780 	u8 first_chain;
781 	u16 i = 0;
782 
783 	average_sig[0] = data->chain_signal_a / IWL_CAL_NUM_BEACONS;
784 	average_sig[1] = data->chain_signal_b / IWL_CAL_NUM_BEACONS;
785 	average_sig[2] = data->chain_signal_c / IWL_CAL_NUM_BEACONS;
786 
787 	if (average_sig[0] >= average_sig[1]) {
788 		max_average_sig = average_sig[0];
789 		max_average_sig_antenna_i = 0;
790 		active_chains = (1 << max_average_sig_antenna_i);
791 	} else {
792 		max_average_sig = average_sig[1];
793 		max_average_sig_antenna_i = 1;
794 		active_chains = (1 << max_average_sig_antenna_i);
795 	}
796 
797 	if (average_sig[2] >= max_average_sig) {
798 		max_average_sig = average_sig[2];
799 		max_average_sig_antenna_i = 2;
800 		active_chains = (1 << max_average_sig_antenna_i);
801 	}
802 
803 	IWL_DEBUG_CALIB(priv, "average_sig: a %d b %d c %d\n",
804 		     average_sig[0], average_sig[1], average_sig[2]);
805 	IWL_DEBUG_CALIB(priv, "max_average_sig = %d, antenna %d\n",
806 		     max_average_sig, max_average_sig_antenna_i);
807 
808 	/* Compare signal strengths for all 3 receivers. */
809 	for (i = 0; i < NUM_RX_CHAINS; i++) {
810 		if (i != max_average_sig_antenna_i) {
811 			s32 rssi_delta = (max_average_sig - average_sig[i]);
812 
813 			/* If signal is very weak, compared with
814 			 * strongest, mark it as disconnected. */
815 			if (rssi_delta > MAXIMUM_ALLOWED_PATHLOSS)
816 				data->disconn_array[i] = 1;
817 			else
818 				active_chains |= (1 << i);
819 			IWL_DEBUG_CALIB(priv, "i = %d  rssiDelta = %d  "
820 			     "disconn_array[i] = %d\n",
821 			     i, rssi_delta, data->disconn_array[i]);
822 		}
823 	}
824 
825 	/*
826 	 * The above algorithm sometimes fails when the ucode
827 	 * reports 0 for all chains. It's not clear why that
828 	 * happens to start with, but it is then causing trouble
829 	 * because this can make us enable more chains than the
830 	 * hardware really has.
831 	 *
832 	 * To be safe, simply mask out any chains that we know
833 	 * are not on the device.
834 	 */
835 	active_chains &= priv->nvm_data->valid_rx_ant;
836 
837 	num_tx_chains = 0;
838 	for (i = 0; i < NUM_RX_CHAINS; i++) {
839 		/* loops on all the bits of
840 		 * priv->hw_setting.valid_tx_ant */
841 		u8 ant_msk = (1 << i);
842 		if (!(priv->nvm_data->valid_tx_ant & ant_msk))
843 			continue;
844 
845 		num_tx_chains++;
846 		if (data->disconn_array[i] == 0)
847 			/* there is a Tx antenna connected */
848 			break;
849 		if (num_tx_chains == priv->hw_params.tx_chains_num &&
850 		    data->disconn_array[i]) {
851 			/*
852 			 * If all chains are disconnected
853 			 * connect the first valid tx chain
854 			 */
855 			first_chain =
856 				find_first_chain(priv->nvm_data->valid_tx_ant);
857 			data->disconn_array[first_chain] = 0;
858 			active_chains |= BIT(first_chain);
859 			IWL_DEBUG_CALIB(priv,
860 					"All Tx chains are disconnected W/A - declare %d as connected\n",
861 					first_chain);
862 			break;
863 		}
864 	}
865 
866 	if (active_chains != priv->nvm_data->valid_rx_ant &&
867 	    active_chains != priv->chain_noise_data.active_chains)
868 		IWL_DEBUG_CALIB(priv,
869 				"Detected that not all antennas are connected! "
870 				"Connected: %#x, valid: %#x.\n",
871 				active_chains,
872 				priv->nvm_data->valid_rx_ant);
873 
874 	/* Save for use within RXON, TX, SCAN commands, etc. */
875 	data->active_chains = active_chains;
876 	IWL_DEBUG_CALIB(priv, "active_chains (bitwise) = 0x%x\n",
877 			active_chains);
878 }
879 
880 static void iwlagn_gain_computation(struct iwl_priv *priv,
881 				    u32 average_noise[NUM_RX_CHAINS],
882 				    u8 default_chain)
883 {
884 	int i;
885 	s32 delta_g;
886 	struct iwl_chain_noise_data *data = &priv->chain_noise_data;
887 
888 	/*
889 	 * Find Gain Code for the chains based on "default chain"
890 	 */
891 	for (i = default_chain + 1; i < NUM_RX_CHAINS; i++) {
892 		if ((data->disconn_array[i])) {
893 			data->delta_gain_code[i] = 0;
894 			continue;
895 		}
896 
897 		delta_g = (priv->lib->chain_noise_scale *
898 			((s32)average_noise[default_chain] -
899 			(s32)average_noise[i])) / 1500;
900 
901 		/* bound gain by 2 bits value max, 3rd bit is sign */
902 		data->delta_gain_code[i] =
903 			min(abs(delta_g), CHAIN_NOISE_MAX_DELTA_GAIN_CODE);
904 
905 		if (delta_g < 0)
906 			/*
907 			 * set negative sign ...
908 			 * note to Intel developers:  This is uCode API format,
909 			 *   not the format of any internal device registers.
910 			 *   Do not change this format for e.g. 6050 or similar
911 			 *   devices.  Change format only if more resolution
912 			 *   (i.e. more than 2 bits magnitude) is needed.
913 			 */
914 			data->delta_gain_code[i] |= (1 << 2);
915 	}
916 
917 	IWL_DEBUG_CALIB(priv, "Delta gains: ANT_B = %d  ANT_C = %d\n",
918 			data->delta_gain_code[1], data->delta_gain_code[2]);
919 
920 	if (!data->radio_write) {
921 		struct iwl_calib_chain_noise_gain_cmd cmd;
922 
923 		memset(&cmd, 0, sizeof(cmd));
924 
925 		iwl_set_calib_hdr(&cmd.hdr,
926 			priv->phy_calib_chain_noise_gain_cmd);
927 		cmd.delta_gain_1 = data->delta_gain_code[1];
928 		cmd.delta_gain_2 = data->delta_gain_code[2];
929 		iwl_dvm_send_cmd_pdu(priv, REPLY_PHY_CALIBRATION_CMD,
930 			CMD_ASYNC, sizeof(cmd), &cmd);
931 
932 		data->radio_write = 1;
933 		data->state = IWL_CHAIN_NOISE_CALIBRATED;
934 	}
935 }
936 
937 /*
938  * Accumulate 16 beacons of signal and noise statistics for each of
939  *   3 receivers/antennas/rx-chains, then figure out:
940  * 1)  Which antennas are connected.
941  * 2)  Differential rx gain settings to balance the 3 receivers.
942  */
943 void iwl_chain_noise_calibration(struct iwl_priv *priv)
944 {
945 	struct iwl_chain_noise_data *data = NULL;
946 
947 	u32 chain_noise_a;
948 	u32 chain_noise_b;
949 	u32 chain_noise_c;
950 	u32 chain_sig_a;
951 	u32 chain_sig_b;
952 	u32 chain_sig_c;
953 	u32 average_sig[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
954 	u32 average_noise[NUM_RX_CHAINS] = {INITIALIZATION_VALUE};
955 	u32 min_average_noise = MIN_AVERAGE_NOISE_MAX_VALUE;
956 	u16 min_average_noise_antenna_i = INITIALIZATION_VALUE;
957 	u16 i = 0;
958 	u16 rxon_chnum = INITIALIZATION_VALUE;
959 	u16 stat_chnum = INITIALIZATION_VALUE;
960 	u8 rxon_band24;
961 	u8 stat_band24;
962 	struct statistics_rx_non_phy *rx_info;
963 
964 	/*
965 	 * MULTI-FIXME:
966 	 * When we support multiple interfaces on different channels,
967 	 * this must be modified/fixed.
968 	 */
969 	struct iwl_rxon_context *ctx = &priv->contexts[IWL_RXON_CTX_BSS];
970 
971 	if (priv->calib_disabled & IWL_CHAIN_NOISE_CALIB_DISABLED)
972 		return;
973 
974 	data = &(priv->chain_noise_data);
975 
976 	/*
977 	 * Accumulate just the first "chain_noise_num_beacons" after
978 	 * the first association, then we're done forever.
979 	 */
980 	if (data->state != IWL_CHAIN_NOISE_ACCUMULATE) {
981 		if (data->state == IWL_CHAIN_NOISE_ALIVE)
982 			IWL_DEBUG_CALIB(priv, "Wait for noise calib reset\n");
983 		return;
984 	}
985 
986 	spin_lock_bh(&priv->statistics.lock);
987 
988 	rx_info = &priv->statistics.rx_non_phy;
989 
990 	if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
991 		IWL_DEBUG_CALIB(priv, " << Interference data unavailable\n");
992 		spin_unlock_bh(&priv->statistics.lock);
993 		return;
994 	}
995 
996 	rxon_band24 = !!(ctx->staging.flags & RXON_FLG_BAND_24G_MSK);
997 	rxon_chnum = le16_to_cpu(ctx->staging.channel);
998 	stat_band24 =
999 		!!(priv->statistics.flag & STATISTICS_REPLY_FLG_BAND_24G_MSK);
1000 	stat_chnum = le32_to_cpu(priv->statistics.flag) >> 16;
1001 
1002 	/* Make sure we accumulate data for just the associated channel
1003 	 *   (even if scanning). */
1004 	if ((rxon_chnum != stat_chnum) || (rxon_band24 != stat_band24)) {
1005 		IWL_DEBUG_CALIB(priv, "Stats not from chan=%d, band24=%d\n",
1006 				rxon_chnum, rxon_band24);
1007 		spin_unlock_bh(&priv->statistics.lock);
1008 		return;
1009 	}
1010 
1011 	/*
1012 	 *  Accumulate beacon statistics values across
1013 	 * "chain_noise_num_beacons"
1014 	 */
1015 	chain_noise_a = le32_to_cpu(rx_info->beacon_silence_rssi_a) &
1016 				IN_BAND_FILTER;
1017 	chain_noise_b = le32_to_cpu(rx_info->beacon_silence_rssi_b) &
1018 				IN_BAND_FILTER;
1019 	chain_noise_c = le32_to_cpu(rx_info->beacon_silence_rssi_c) &
1020 				IN_BAND_FILTER;
1021 
1022 	chain_sig_a = le32_to_cpu(rx_info->beacon_rssi_a) & IN_BAND_FILTER;
1023 	chain_sig_b = le32_to_cpu(rx_info->beacon_rssi_b) & IN_BAND_FILTER;
1024 	chain_sig_c = le32_to_cpu(rx_info->beacon_rssi_c) & IN_BAND_FILTER;
1025 
1026 	spin_unlock_bh(&priv->statistics.lock);
1027 
1028 	data->beacon_count++;
1029 
1030 	data->chain_noise_a = (chain_noise_a + data->chain_noise_a);
1031 	data->chain_noise_b = (chain_noise_b + data->chain_noise_b);
1032 	data->chain_noise_c = (chain_noise_c + data->chain_noise_c);
1033 
1034 	data->chain_signal_a = (chain_sig_a + data->chain_signal_a);
1035 	data->chain_signal_b = (chain_sig_b + data->chain_signal_b);
1036 	data->chain_signal_c = (chain_sig_c + data->chain_signal_c);
1037 
1038 	IWL_DEBUG_CALIB(priv, "chan=%d, band24=%d, beacon=%d\n",
1039 			rxon_chnum, rxon_band24, data->beacon_count);
1040 	IWL_DEBUG_CALIB(priv, "chain_sig: a %d b %d c %d\n",
1041 			chain_sig_a, chain_sig_b, chain_sig_c);
1042 	IWL_DEBUG_CALIB(priv, "chain_noise: a %d b %d c %d\n",
1043 			chain_noise_a, chain_noise_b, chain_noise_c);
1044 
1045 	/* If this is the "chain_noise_num_beacons", determine:
1046 	 * 1)  Disconnected antennas (using signal strengths)
1047 	 * 2)  Differential gain (using silence noise) to balance receivers */
1048 	if (data->beacon_count != IWL_CAL_NUM_BEACONS)
1049 		return;
1050 
1051 	/* Analyze signal for disconnected antenna */
1052 	if (priv->lib->bt_params &&
1053 	    priv->lib->bt_params->advanced_bt_coexist) {
1054 		/* Disable disconnected antenna algorithm for advanced
1055 		   bt coex, assuming valid antennas are connected */
1056 		data->active_chains = priv->nvm_data->valid_rx_ant;
1057 		for (i = 0; i < NUM_RX_CHAINS; i++)
1058 			if (!(data->active_chains & (1<<i)))
1059 				data->disconn_array[i] = 1;
1060 	} else
1061 		iwl_find_disconn_antenna(priv, average_sig, data);
1062 
1063 	/* Analyze noise for rx balance */
1064 	average_noise[0] = data->chain_noise_a / IWL_CAL_NUM_BEACONS;
1065 	average_noise[1] = data->chain_noise_b / IWL_CAL_NUM_BEACONS;
1066 	average_noise[2] = data->chain_noise_c / IWL_CAL_NUM_BEACONS;
1067 
1068 	for (i = 0; i < NUM_RX_CHAINS; i++) {
1069 		if (!(data->disconn_array[i]) &&
1070 		   (average_noise[i] <= min_average_noise)) {
1071 			/* This means that chain i is active and has
1072 			 * lower noise values so far: */
1073 			min_average_noise = average_noise[i];
1074 			min_average_noise_antenna_i = i;
1075 		}
1076 	}
1077 
1078 	IWL_DEBUG_CALIB(priv, "average_noise: a %d b %d c %d\n",
1079 			average_noise[0], average_noise[1],
1080 			average_noise[2]);
1081 
1082 	IWL_DEBUG_CALIB(priv, "min_average_noise = %d, antenna %d\n",
1083 			min_average_noise, min_average_noise_antenna_i);
1084 
1085 	iwlagn_gain_computation(
1086 		priv, average_noise,
1087 		find_first_chain(priv->nvm_data->valid_rx_ant));
1088 
1089 	/* Some power changes may have been made during the calibration.
1090 	 * Update and commit the RXON
1091 	 */
1092 	iwl_update_chain_flags(priv);
1093 
1094 	data->state = IWL_CHAIN_NOISE_DONE;
1095 	iwl_power_update_mode(priv, false);
1096 }
1097 
1098 void iwl_reset_run_time_calib(struct iwl_priv *priv)
1099 {
1100 	int i;
1101 	memset(&(priv->sensitivity_data), 0,
1102 	       sizeof(struct iwl_sensitivity_data));
1103 	memset(&(priv->chain_noise_data), 0,
1104 	       sizeof(struct iwl_chain_noise_data));
1105 	for (i = 0; i < NUM_RX_CHAINS; i++)
1106 		priv->chain_noise_data.delta_gain_code[i] =
1107 				CHAIN_NOISE_DELTA_GAIN_INIT_VAL;
1108 
1109 	/* Ask for statistics now, the uCode will send notification
1110 	 * periodically after association */
1111 	iwl_send_statistics_request(priv, CMD_ASYNC, true);
1112 }
1113