intel/iwlegacy/4965-calib.c

0001 /******************************************************************************
0002  *
0003  * This file is provided under a dual BSD/GPLv2 license.  When using or
0004  * redistributing this file, you may do so under either license.
0005  *
0006  * GPL LICENSE SUMMARY
0007  *
0008  * Copyright(c) 2008 - 2011 Intel Corporation. All rights reserved.
0009  *
0010  * This program is free software; you can redistribute it and/or modify
0011  * it under the terms of version 2 of the GNU General Public License as
0012  * published by the Free Software Foundation.
0013  *
0014  * This program is distributed in the hope that it will be useful, but
0015  * WITHOUT ANY WARRANTY; without even the implied warranty of
0016  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
0017  * General Public License for more details.
0018  *
0019  * You should have received a copy of the GNU General Public License
0020  * along with this program; if not, write to the Free Software
0021  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110,
0022  * USA
0023  *
0024  * The full GNU General Public License is included in this distribution
0025  * in the file called LICENSE.GPL.
0026  *
0027  * Contact Information:
0028  *  Intel Linux Wireless <ilw@linux.intel.com>
0029  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
0030  *
0031  * BSD LICENSE
0032  *
0033  * Copyright(c) 2005 - 2011 Intel Corporation. All rights reserved.
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0037  * modification, are permitted provided that the following conditions
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0041  *    notice, this list of conditions and the following disclaimer.
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0055  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
0056  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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0059  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
0060  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
0061  *****************************************************************************/
0062
0063 #include <linux/slab.h>
0064 #include <net/mac80211.h>
0065
0066 #include "common.h"
0067 #include "4965.h"
0068
0069 /*****************************************************************************
0070  * INIT calibrations framework
0071  *****************************************************************************/
0072
0073 struct stats_general_data {
0074     u32 beacon_silence_rssi_a;
0075     u32 beacon_silence_rssi_b;
0076     u32 beacon_silence_rssi_c;
0077     u32 beacon_energy_a;
0078     u32 beacon_energy_b;
0079     u32 beacon_energy_c;
0080 };
0081
0082 /*****************************************************************************
0083  * RUNTIME calibrations framework
0084  *****************************************************************************/
0085
0086 /* "false alarms" are signals that our DSP tries to lock onto,
0087  *   but then determines that they are either noise, or transmissions
0088  *   from a distant wireless network (also "noise", really) that get
0089  *   "stepped on" by stronger transmissions within our own network.
0090  * This algorithm attempts to set a sensitivity level that is high
0091  *   enough to receive all of our own network traffic, but not so
0092  *   high that our DSP gets too busy trying to lock onto non-network
0093  *   activity/noise. */
0094 static int
0095 il4965_sens_energy_cck(struct il_priv *il, u32 norm_fa, u32 rx_enable_time,
0096                struct stats_general_data *rx_info)
0097 {
0098     u32 max_nrg_cck = 0;
0099     int i = 0;
0100     u8 max_silence_rssi = 0;
0101     u32 silence_ref = 0;
0102     u8 silence_rssi_a = 0;
0103     u8 silence_rssi_b = 0;
0104     u8 silence_rssi_c = 0;
0105     u32 val;
0106
0107     /* "false_alarms" values below are cross-multiplications to assess the
0108      *   numbers of false alarms within the measured period of actual Rx
0109      *   (Rx is off when we're txing), vs the min/max expected false alarms
0110      *   (some should be expected if rx is sensitive enough) in a
0111      *   hypothetical listening period of 200 time units (TU), 204.8 msec:
0112      *
0113      * MIN_FA/fixed-time < false_alarms/actual-rx-time < MAX_FA/beacon-time
0114      *
0115      * */
0116     u32 false_alarms = norm_fa * 200 * 1024;
0117     u32 max_false_alarms = MAX_FA_CCK * rx_enable_time;
0118     u32 min_false_alarms = MIN_FA_CCK * rx_enable_time;
0119     struct il_sensitivity_data *data = NULL;
0120     const struct il_sensitivity_ranges *ranges = il->hw_params.sens;
0121
0122     data = &(il->sensitivity_data);
0123
0124     data->nrg_auto_corr_silence_diff = 0;
0125
0126     /* Find max silence rssi among all 3 receivers.
0127      * This is background noise, which may include transmissions from other
0128      *    networks, measured during silence before our network's beacon */
0129     silence_rssi_a =
0130         (u8) ((rx_info->beacon_silence_rssi_a & ALL_BAND_FILTER) >> 8);
0131     silence_rssi_b =
0132         (u8) ((rx_info->beacon_silence_rssi_b & ALL_BAND_FILTER) >> 8);
0133     silence_rssi_c =
0134         (u8) ((rx_info->beacon_silence_rssi_c & ALL_BAND_FILTER) >> 8);
0135
0136     val = max(silence_rssi_b, silence_rssi_c);
0137     max_silence_rssi = max(silence_rssi_a, (u8) val);
0138
0139     /* Store silence rssi in 20-beacon history table */
0140     data->nrg_silence_rssi[data->nrg_silence_idx] = max_silence_rssi;
0141     data->nrg_silence_idx++;
0142     if (data->nrg_silence_idx >= NRG_NUM_PREV_STAT_L)
0143         data->nrg_silence_idx = 0;
0144
0145     /* Find max silence rssi across 20 beacon history */
0146     for (i = 0; i < NRG_NUM_PREV_STAT_L; i++) {
0147         val = data->nrg_silence_rssi[i];
0148         silence_ref = max(silence_ref, val);
0149     }
0150     D_CALIB("silence a %u, b %u, c %u, 20-bcn max %u\n", silence_rssi_a,
0151         silence_rssi_b, silence_rssi_c, silence_ref);
0152
0153     /* Find max rx energy (min value!) among all 3 receivers,
0154      *   measured during beacon frame.
0155      * Save it in 10-beacon history table. */
0156     i = data->nrg_energy_idx;
0157     val = min(rx_info->beacon_energy_b, rx_info->beacon_energy_c);
0158     data->nrg_value[i] = min(rx_info->beacon_energy_a, val);
0159
0160     data->nrg_energy_idx++;
0161     if (data->nrg_energy_idx >= 10)
0162         data->nrg_energy_idx = 0;
0163
0164     /* Find min rx energy (max value) across 10 beacon history.
0165      * This is the minimum signal level that we want to receive well.
0166      * Add backoff (margin so we don't miss slightly lower energy frames).
0167      * This establishes an upper bound (min value) for energy threshold. */
0168     max_nrg_cck = data->nrg_value[0];
0169     for (i = 1; i < 10; i++)
0170         max_nrg_cck = (u32) max(max_nrg_cck, (data->nrg_value[i]));
0171     max_nrg_cck += 6;
0172
0173     D_CALIB("rx energy a %u, b %u, c %u, 10-bcn max/min %u\n",
0174         rx_info->beacon_energy_a, rx_info->beacon_energy_b,
0175         rx_info->beacon_energy_c, max_nrg_cck - 6);
0176
0177     /* Count number of consecutive beacons with fewer-than-desired
0178      *   false alarms. */
0179     if (false_alarms < min_false_alarms)
0180         data->num_in_cck_no_fa++;
0181     else
0182         data->num_in_cck_no_fa = 0;
0183     D_CALIB("consecutive bcns with few false alarms = %u\n",
0184         data->num_in_cck_no_fa);
0185
0186     /* If we got too many false alarms this time, reduce sensitivity */
0187     if (false_alarms > max_false_alarms &&
0188         data->auto_corr_cck > AUTO_CORR_MAX_TH_CCK) {
0189         D_CALIB("norm FA %u > max FA %u\n", false_alarms,
0190             max_false_alarms);
0191         D_CALIB("... reducing sensitivity\n");
0192         data->nrg_curr_state = IL_FA_TOO_MANY;
0193         /* Store for "fewer than desired" on later beacon */
0194         data->nrg_silence_ref = silence_ref;
0195
0196         /* increase energy threshold (reduce nrg value)
0197          *   to decrease sensitivity */
0198         data->nrg_th_cck = data->nrg_th_cck - NRG_STEP_CCK;
0199         /* Else if we got fewer than desired, increase sensitivity */
0200     } else if (false_alarms < min_false_alarms) {
0201         data->nrg_curr_state = IL_FA_TOO_FEW;
0202
0203         /* Compare silence level with silence level for most recent
0204          *   healthy number or too many false alarms */
0205         data->nrg_auto_corr_silence_diff =
0206             (s32) data->nrg_silence_ref - (s32) silence_ref;
0207
0208         D_CALIB("norm FA %u < min FA %u, silence diff %d\n",
0209             false_alarms, min_false_alarms,
0210             data->nrg_auto_corr_silence_diff);
0211
0212         /* Increase value to increase sensitivity, but only if:
0213          * 1a) previous beacon did *not* have *too many* false alarms
0214          * 1b) AND there's a significant difference in Rx levels
0215          *      from a previous beacon with too many, or healthy # FAs
0216          * OR 2) We've seen a lot of beacons (100) with too few
0217          *       false alarms */
0218         if (data->nrg_prev_state != IL_FA_TOO_MANY &&
0219             (data->nrg_auto_corr_silence_diff > NRG_DIFF ||
0220              data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA)) {
0221
0222             D_CALIB("... increasing sensitivity\n");
0223             /* Increase nrg value to increase sensitivity */
0224             val = data->nrg_th_cck + NRG_STEP_CCK;
0225             data->nrg_th_cck = min((u32) ranges->min_nrg_cck, val);
0226         } else {
0227             D_CALIB("... but not changing sensitivity\n");
0228         }
0229
0230         /* Else we got a healthy number of false alarms, keep status quo */
0231     } else {
0232         D_CALIB(" FA in safe zone\n");
0233         data->nrg_curr_state = IL_FA_GOOD_RANGE;
0234
0235         /* Store for use in "fewer than desired" with later beacon */
0236         data->nrg_silence_ref = silence_ref;
0237
0238         /* If previous beacon had too many false alarms,
0239          *   give it some extra margin by reducing sensitivity again
0240          *   (but don't go below measured energy of desired Rx) */
0241         if (IL_FA_TOO_MANY == data->nrg_prev_state) {
0242             D_CALIB("... increasing margin\n");
0243             if (data->nrg_th_cck > (max_nrg_cck + NRG_MARGIN))
0244                 data->nrg_th_cck -= NRG_MARGIN;
0245             else
0246                 data->nrg_th_cck = max_nrg_cck;
0247         }
0248     }
0249
0250     /* Make sure the energy threshold does not go above the measured
0251      * energy of the desired Rx signals (reduced by backoff margin),
0252      * or else we might start missing Rx frames.
0253      * Lower value is higher energy, so we use max()!
0254      */
0255     data->nrg_th_cck = max(max_nrg_cck, data->nrg_th_cck);
0256     D_CALIB("new nrg_th_cck %u\n", data->nrg_th_cck);
0257
0258     data->nrg_prev_state = data->nrg_curr_state;
0259
0260     /* Auto-correlation CCK algorithm */
0261     if (false_alarms > min_false_alarms) {
0262
0263         /* increase auto_corr values to decrease sensitivity
0264          * so the DSP won't be disturbed by the noise
0265          */
0266         if (data->auto_corr_cck < AUTO_CORR_MAX_TH_CCK)
0267             data->auto_corr_cck = AUTO_CORR_MAX_TH_CCK + 1;
0268         else {
0269             val = data->auto_corr_cck + AUTO_CORR_STEP_CCK;
0270             data->auto_corr_cck =
0271                 min((u32) ranges->auto_corr_max_cck, val);
0272         }
0273         val = data->auto_corr_cck_mrc + AUTO_CORR_STEP_CCK;
0274         data->auto_corr_cck_mrc =
0275             min((u32) ranges->auto_corr_max_cck_mrc, val);
0276     } else if (false_alarms < min_false_alarms &&
0277            (data->nrg_auto_corr_silence_diff > NRG_DIFF ||
0278             data->num_in_cck_no_fa > MAX_NUMBER_CCK_NO_FA)) {
0279
0280         /* Decrease auto_corr values to increase sensitivity */
0281         val = data->auto_corr_cck - AUTO_CORR_STEP_CCK;
0282         data->auto_corr_cck = max((u32) ranges->auto_corr_min_cck, val);
0283         val = data->auto_corr_cck_mrc - AUTO_CORR_STEP_CCK;
0284         data->auto_corr_cck_mrc =
0285             max((u32) ranges->auto_corr_min_cck_mrc, val);
0286     }
0287
0288     return 0;
0289 }
0290
0291 static int
0292 il4965_sens_auto_corr_ofdm(struct il_priv *il, u32 norm_fa, u32 rx_enable_time)
0293 {
0294     u32 val;
0295     u32 false_alarms = norm_fa * 200 * 1024;
0296     u32 max_false_alarms = MAX_FA_OFDM * rx_enable_time;
0297     u32 min_false_alarms = MIN_FA_OFDM * rx_enable_time;
0298     struct il_sensitivity_data *data = NULL;
0299     const struct il_sensitivity_ranges *ranges = il->hw_params.sens;
0300
0301     data = &(il->sensitivity_data);
0302
0303     /* If we got too many false alarms this time, reduce sensitivity */
0304     if (false_alarms > max_false_alarms) {
0305
0306         D_CALIB("norm FA %u > max FA %u)\n", false_alarms,
0307             max_false_alarms);
0308
0309         val = data->auto_corr_ofdm + AUTO_CORR_STEP_OFDM;
0310         data->auto_corr_ofdm =
0311             min((u32) ranges->auto_corr_max_ofdm, val);
0312
0313         val = data->auto_corr_ofdm_mrc + AUTO_CORR_STEP_OFDM;
0314         data->auto_corr_ofdm_mrc =
0315             min((u32) ranges->auto_corr_max_ofdm_mrc, val);
0316
0317         val = data->auto_corr_ofdm_x1 + AUTO_CORR_STEP_OFDM;
0318         data->auto_corr_ofdm_x1 =
0319             min((u32) ranges->auto_corr_max_ofdm_x1, val);
0320
0321         val = data->auto_corr_ofdm_mrc_x1 + AUTO_CORR_STEP_OFDM;
0322         data->auto_corr_ofdm_mrc_x1 =
0323             min((u32) ranges->auto_corr_max_ofdm_mrc_x1, val);
0324     }
0325
0326     /* Else if we got fewer than desired, increase sensitivity */
0327     else if (false_alarms < min_false_alarms) {
0328
0329         D_CALIB("norm FA %u < min FA %u\n", false_alarms,
0330             min_false_alarms);
0331
0332         val = data->auto_corr_ofdm - AUTO_CORR_STEP_OFDM;
0333         data->auto_corr_ofdm =
0334             max((u32) ranges->auto_corr_min_ofdm, val);
0335
0336         val = data->auto_corr_ofdm_mrc - AUTO_CORR_STEP_OFDM;
0337         data->auto_corr_ofdm_mrc =
0338             max((u32) ranges->auto_corr_min_ofdm_mrc, val);
0339
0340         val = data->auto_corr_ofdm_x1 - AUTO_CORR_STEP_OFDM;
0341         data->auto_corr_ofdm_x1 =
0342             max((u32) ranges->auto_corr_min_ofdm_x1, val);
0343
0344         val = data->auto_corr_ofdm_mrc_x1 - AUTO_CORR_STEP_OFDM;
0345         data->auto_corr_ofdm_mrc_x1 =
0346             max((u32) ranges->auto_corr_min_ofdm_mrc_x1, val);
0347     } else {
0348         D_CALIB("min FA %u < norm FA %u < max FA %u OK\n",
0349             min_false_alarms, false_alarms, max_false_alarms);
0350     }
0351     return 0;
0352 }
0353
0354 static void
0355 il4965_prepare_legacy_sensitivity_tbl(struct il_priv *il,
0356                       struct il_sensitivity_data *data,
0357                       __le16 *tbl)
0358 {
0359     tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_IDX] =
0360         cpu_to_le16((u16) data->auto_corr_ofdm);
0361     tbl[HD_AUTO_CORR32_X4_TH_ADD_MIN_MRC_IDX] =
0362         cpu_to_le16((u16) data->auto_corr_ofdm_mrc);
0363     tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_IDX] =
0364         cpu_to_le16((u16) data->auto_corr_ofdm_x1);
0365     tbl[HD_AUTO_CORR32_X1_TH_ADD_MIN_MRC_IDX] =
0366         cpu_to_le16((u16) data->auto_corr_ofdm_mrc_x1);
0367
0368     tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_IDX] =
0369         cpu_to_le16((u16) data->auto_corr_cck);
0370     tbl[HD_AUTO_CORR40_X4_TH_ADD_MIN_MRC_IDX] =
0371         cpu_to_le16((u16) data->auto_corr_cck_mrc);
0372
0373     tbl[HD_MIN_ENERGY_CCK_DET_IDX] = cpu_to_le16((u16) data->nrg_th_cck);
0374     tbl[HD_MIN_ENERGY_OFDM_DET_IDX] = cpu_to_le16((u16) data->nrg_th_ofdm);
0375
0376     tbl[HD_BARKER_CORR_TH_ADD_MIN_IDX] =
0377         cpu_to_le16(data->barker_corr_th_min);
0378     tbl[HD_BARKER_CORR_TH_ADD_MIN_MRC_IDX] =
0379         cpu_to_le16(data->barker_corr_th_min_mrc);
0380     tbl[HD_OFDM_ENERGY_TH_IN_IDX] = cpu_to_le16(data->nrg_th_cca);
0381
0382     D_CALIB("ofdm: ac %u mrc %u x1 %u mrc_x1 %u thresh %u\n",
0383         data->auto_corr_ofdm, data->auto_corr_ofdm_mrc,
0384         data->auto_corr_ofdm_x1, data->auto_corr_ofdm_mrc_x1,
0385         data->nrg_th_ofdm);
0386
0387     D_CALIB("cck: ac %u mrc %u thresh %u\n", data->auto_corr_cck,
0388         data->auto_corr_cck_mrc, data->nrg_th_cck);
0389 }
0390
0391 /* Prepare a C_SENSITIVITY, send to uCode if values have changed */
0392 static int
0393 il4965_sensitivity_write(struct il_priv *il)
0394 {
0395     struct il_sensitivity_cmd cmd;
0396     struct il_sensitivity_data *data = NULL;
0397     struct il_host_cmd cmd_out = {
0398         .id = C_SENSITIVITY,
0399         .len = sizeof(struct il_sensitivity_cmd),
0400         .flags = CMD_ASYNC,
0401         .data = &cmd,
0402     };
0403
0404     data = &(il->sensitivity_data);
0405
0406     memset(&cmd, 0, sizeof(cmd));
0407
0408     il4965_prepare_legacy_sensitivity_tbl(il, data, &cmd.table[0]);
0409
0410     /* Update uCode's "work" table, and copy it to DSP */
0411     cmd.control = C_SENSITIVITY_CONTROL_WORK_TBL;
0412
0413     /* Don't send command to uCode if nothing has changed */
0414     if (!memcmp
0415         (&cmd.table[0], &(il->sensitivity_tbl[0]),
0416          sizeof(u16) * HD_TBL_SIZE)) {
0417         D_CALIB("No change in C_SENSITIVITY\n");
0418         return 0;
0419     }
0420
0421     /* Copy table for comparison next time */
0422     memcpy(&(il->sensitivity_tbl[0]), &(cmd.table[0]),
0423            sizeof(u16) * HD_TBL_SIZE);
0424
0425     return il_send_cmd(il, &cmd_out);
0426 }
0427
0428 void
0429 il4965_init_sensitivity(struct il_priv *il)
0430 {
0431     int ret = 0;
0432     int i;
0433     struct il_sensitivity_data *data = NULL;
0434     const struct il_sensitivity_ranges *ranges = il->hw_params.sens;
0435
0436     if (il->disable_sens_cal)
0437         return;
0438
0439     D_CALIB("Start il4965_init_sensitivity\n");
0440
0441     /* Clear driver's sensitivity algo data */
0442     data = &(il->sensitivity_data);
0443
0444     if (ranges == NULL)
0445         return;
0446
0447     memset(data, 0, sizeof(struct il_sensitivity_data));
0448
0449     data->num_in_cck_no_fa = 0;
0450     data->nrg_curr_state = IL_FA_TOO_MANY;
0451     data->nrg_prev_state = IL_FA_TOO_MANY;
0452     data->nrg_silence_ref = 0;
0453     data->nrg_silence_idx = 0;
0454     data->nrg_energy_idx = 0;
0455
0456     for (i = 0; i < 10; i++)
0457         data->nrg_value[i] = 0;
0458
0459     for (i = 0; i < NRG_NUM_PREV_STAT_L; i++)
0460         data->nrg_silence_rssi[i] = 0;
0461
0462     data->auto_corr_ofdm = ranges->auto_corr_min_ofdm;
0463     data->auto_corr_ofdm_mrc = ranges->auto_corr_min_ofdm_mrc;
0464     data->auto_corr_ofdm_x1 = ranges->auto_corr_min_ofdm_x1;
0465     data->auto_corr_ofdm_mrc_x1 = ranges->auto_corr_min_ofdm_mrc_x1;
0466     data->auto_corr_cck = AUTO_CORR_CCK_MIN_VAL_DEF;
0467     data->auto_corr_cck_mrc = ranges->auto_corr_min_cck_mrc;
0468     data->nrg_th_cck = ranges->nrg_th_cck;
0469     data->nrg_th_ofdm = ranges->nrg_th_ofdm;
0470     data->barker_corr_th_min = ranges->barker_corr_th_min;
0471     data->barker_corr_th_min_mrc = ranges->barker_corr_th_min_mrc;
0472     data->nrg_th_cca = ranges->nrg_th_cca;
0473
0474     data->last_bad_plcp_cnt_ofdm = 0;
0475     data->last_fa_cnt_ofdm = 0;
0476     data->last_bad_plcp_cnt_cck = 0;
0477     data->last_fa_cnt_cck = 0;
0478
0479     ret |= il4965_sensitivity_write(il);
0480     D_CALIB("<<return 0x%X\n", ret);
0481 }
0482
0483 void
0484 il4965_sensitivity_calibration(struct il_priv *il, void *resp)
0485 {
0486     u32 rx_enable_time;
0487     u32 fa_cck;
0488     u32 fa_ofdm;
0489     u32 bad_plcp_cck;
0490     u32 bad_plcp_ofdm;
0491     u32 norm_fa_ofdm;
0492     u32 norm_fa_cck;
0493     struct il_sensitivity_data *data = NULL;
0494     struct stats_rx_non_phy *rx_info;
0495     struct stats_rx_phy *ofdm, *cck;
0496     unsigned long flags;
0497     struct stats_general_data statis;
0498
0499     if (il->disable_sens_cal)
0500         return;
0501
0502     data = &(il->sensitivity_data);
0503
0504     if (!il_is_any_associated(il)) {
0505         D_CALIB("<< - not associated\n");
0506         return;
0507     }
0508
0509     spin_lock_irqsave(&il->lock, flags);
0510
0511     rx_info = &(((struct il_notif_stats *)resp)->rx.general);
0512     ofdm = &(((struct il_notif_stats *)resp)->rx.ofdm);
0513     cck = &(((struct il_notif_stats *)resp)->rx.cck);
0514
0515     if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
0516         D_CALIB("<< invalid data.\n");
0517         spin_unlock_irqrestore(&il->lock, flags);
0518         return;
0519     }
0520
0521     /* Extract Statistics: */
0522     rx_enable_time = le32_to_cpu(rx_info->channel_load);
0523     fa_cck = le32_to_cpu(cck->false_alarm_cnt);
0524     fa_ofdm = le32_to_cpu(ofdm->false_alarm_cnt);
0525     bad_plcp_cck = le32_to_cpu(cck->plcp_err);
0526     bad_plcp_ofdm = le32_to_cpu(ofdm->plcp_err);
0527
0528     statis.beacon_silence_rssi_a =
0529         le32_to_cpu(rx_info->beacon_silence_rssi_a);
0530     statis.beacon_silence_rssi_b =
0531         le32_to_cpu(rx_info->beacon_silence_rssi_b);
0532     statis.beacon_silence_rssi_c =
0533         le32_to_cpu(rx_info->beacon_silence_rssi_c);
0534     statis.beacon_energy_a = le32_to_cpu(rx_info->beacon_energy_a);
0535     statis.beacon_energy_b = le32_to_cpu(rx_info->beacon_energy_b);
0536     statis.beacon_energy_c = le32_to_cpu(rx_info->beacon_energy_c);
0537
0538     spin_unlock_irqrestore(&il->lock, flags);
0539
0540     D_CALIB("rx_enable_time = %u usecs\n", rx_enable_time);
0541
0542     if (!rx_enable_time) {
0543         D_CALIB("<< RX Enable Time == 0!\n");
0544         return;
0545     }
0546
0547     /* These stats increase monotonically, and do not reset
0548      *   at each beacon.  Calculate difference from last value, or just
0549      *   use the new stats value if it has reset or wrapped around. */
0550     if (data->last_bad_plcp_cnt_cck > bad_plcp_cck)
0551         data->last_bad_plcp_cnt_cck = bad_plcp_cck;
0552     else {
0553         bad_plcp_cck -= data->last_bad_plcp_cnt_cck;
0554         data->last_bad_plcp_cnt_cck += bad_plcp_cck;
0555     }
0556
0557     if (data->last_bad_plcp_cnt_ofdm > bad_plcp_ofdm)
0558         data->last_bad_plcp_cnt_ofdm = bad_plcp_ofdm;
0559     else {
0560         bad_plcp_ofdm -= data->last_bad_plcp_cnt_ofdm;
0561         data->last_bad_plcp_cnt_ofdm += bad_plcp_ofdm;
0562     }
0563
0564     if (data->last_fa_cnt_ofdm > fa_ofdm)
0565         data->last_fa_cnt_ofdm = fa_ofdm;
0566     else {
0567         fa_ofdm -= data->last_fa_cnt_ofdm;
0568         data->last_fa_cnt_ofdm += fa_ofdm;
0569     }
0570
0571     if (data->last_fa_cnt_cck > fa_cck)
0572         data->last_fa_cnt_cck = fa_cck;
0573     else {
0574         fa_cck -= data->last_fa_cnt_cck;
0575         data->last_fa_cnt_cck += fa_cck;
0576     }
0577
0578     /* Total aborted signal locks */
0579     norm_fa_ofdm = fa_ofdm + bad_plcp_ofdm;
0580     norm_fa_cck = fa_cck + bad_plcp_cck;
0581
0582     D_CALIB("cck: fa %u badp %u  ofdm: fa %u badp %u\n", fa_cck,
0583         bad_plcp_cck, fa_ofdm, bad_plcp_ofdm);
0584
0585     il4965_sens_auto_corr_ofdm(il, norm_fa_ofdm, rx_enable_time);
0586     il4965_sens_energy_cck(il, norm_fa_cck, rx_enable_time, &statis);
0587
0588     il4965_sensitivity_write(il);
0589 }
0590
0591 static inline u8
0592 il4965_find_first_chain(u8 mask)
0593 {
0594     if (mask & ANT_A)
0595         return CHAIN_A;
0596     if (mask & ANT_B)
0597         return CHAIN_B;
0598     return CHAIN_C;
0599 }
0600
0601 /*
0602  * Run disconnected antenna algorithm to find out which antennas are
0603  * disconnected.
0604  */
0605 static void
0606 il4965_find_disconn_antenna(struct il_priv *il, u32 * average_sig,
0607                 struct il_chain_noise_data *data)
0608 {
0609     u32 active_chains = 0;
0610     u32 max_average_sig;
0611     u16 max_average_sig_antenna_i;
0612     u8 num_tx_chains;
0613     u8 first_chain;
0614     u16 i = 0;
0615
0616     average_sig[0] =
0617         data->chain_signal_a /
0618         il->cfg->chain_noise_num_beacons;
0619     average_sig[1] =
0620         data->chain_signal_b /
0621         il->cfg->chain_noise_num_beacons;
0622     average_sig[2] =
0623         data->chain_signal_c /
0624         il->cfg->chain_noise_num_beacons;
0625
0626     if (average_sig[0] >= average_sig[1]) {
0627         max_average_sig = average_sig[0];
0628         max_average_sig_antenna_i = 0;
0629         active_chains = (1 << max_average_sig_antenna_i);
0630     } else {
0631         max_average_sig = average_sig[1];
0632         max_average_sig_antenna_i = 1;
0633         active_chains = (1 << max_average_sig_antenna_i);
0634     }
0635
0636     if (average_sig[2] >= max_average_sig) {
0637         max_average_sig = average_sig[2];
0638         max_average_sig_antenna_i = 2;
0639         active_chains = (1 << max_average_sig_antenna_i);
0640     }
0641
0642     D_CALIB("average_sig: a %d b %d c %d\n", average_sig[0], average_sig[1],
0643         average_sig[2]);
0644     D_CALIB("max_average_sig = %d, antenna %d\n", max_average_sig,
0645         max_average_sig_antenna_i);
0646
0647     /* Compare signal strengths for all 3 receivers. */
0648     for (i = 0; i < NUM_RX_CHAINS; i++) {
0649         if (i != max_average_sig_antenna_i) {
0650             s32 rssi_delta = (max_average_sig - average_sig[i]);
0651
0652             /* If signal is very weak, compared with
0653              * strongest, mark it as disconnected. */
0654             if (rssi_delta > MAXIMUM_ALLOWED_PATHLOSS)
0655                 data->disconn_array[i] = 1;
0656             else
0657                 active_chains |= (1 << i);
0658             D_CALIB("i = %d  rssiDelta = %d  "
0659                 "disconn_array[i] = %d\n", i, rssi_delta,
0660                 data->disconn_array[i]);
0661         }
0662     }
0663
0664     /*
0665      * The above algorithm sometimes fails when the ucode
0666      * reports 0 for all chains. It's not clear why that
0667      * happens to start with, but it is then causing trouble
0668      * because this can make us enable more chains than the
0669      * hardware really has.
0670      *
0671      * To be safe, simply mask out any chains that we know
0672      * are not on the device.
0673      */
0674     active_chains &= il->hw_params.valid_rx_ant;
0675
0676     num_tx_chains = 0;
0677     for (i = 0; i < NUM_RX_CHAINS; i++) {
0678         /* loops on all the bits of
0679          * il->hw_setting.valid_tx_ant */
0680         u8 ant_msk = (1 << i);
0681         if (!(il->hw_params.valid_tx_ant & ant_msk))
0682             continue;
0683
0684         num_tx_chains++;
0685         if (data->disconn_array[i] == 0)
0686             /* there is a Tx antenna connected */
0687             break;
0688         if (num_tx_chains == il->hw_params.tx_chains_num &&
0689             data->disconn_array[i]) {
0690             /*
0691              * If all chains are disconnected
0692              * connect the first valid tx chain
0693              */
0694             first_chain =
0695                 il4965_find_first_chain(il->cfg->valid_tx_ant);
0696             data->disconn_array[first_chain] = 0;
0697             active_chains |= BIT(first_chain);
0698             D_CALIB("All Tx chains are disconnected"
0699                 "- declare %d as connected\n", first_chain);
0700             break;
0701         }
0702     }
0703
0704     if (active_chains != il->hw_params.valid_rx_ant &&
0705         active_chains != il->chain_noise_data.active_chains)
0706         D_CALIB("Detected that not all antennas are connected! "
0707             "Connected: %#x, valid: %#x.\n", active_chains,
0708             il->hw_params.valid_rx_ant);
0709
0710     /* Save for use within RXON, TX, SCAN commands, etc. */
0711     data->active_chains = active_chains;
0712     D_CALIB("active_chains (bitwise) = 0x%x\n", active_chains);
0713 }
0714
0715 static void
0716 il4965_gain_computation(struct il_priv *il, u32 * average_noise,
0717             u16 min_average_noise_antenna_i, u32 min_average_noise,
0718             u8 default_chain)
0719 {
0720     int i, ret;
0721     struct il_chain_noise_data *data = &il->chain_noise_data;
0722
0723     data->delta_gain_code[min_average_noise_antenna_i] = 0;
0724
0725     for (i = default_chain; i < NUM_RX_CHAINS; i++) {
0726         s32 delta_g = 0;
0727
0728         if (!data->disconn_array[i] &&
0729             data->delta_gain_code[i] ==
0730             CHAIN_NOISE_DELTA_GAIN_INIT_VAL) {
0731             delta_g = average_noise[i] - min_average_noise;
0732             data->delta_gain_code[i] = (u8) ((delta_g * 10) / 15);
0733             data->delta_gain_code[i] =
0734                 min(data->delta_gain_code[i],
0735                 (u8) CHAIN_NOISE_MAX_DELTA_GAIN_CODE);
0736
0737             data->delta_gain_code[i] =
0738                 (data->delta_gain_code[i] | (1 << 2));
0739         } else {
0740             data->delta_gain_code[i] = 0;
0741         }
0742     }
0743     D_CALIB("delta_gain_codes: a %d b %d c %d\n", data->delta_gain_code[0],
0744         data->delta_gain_code[1], data->delta_gain_code[2]);
0745
0746     /* Differential gain gets sent to uCode only once */
0747     if (!data->radio_write) {
0748         struct il_calib_diff_gain_cmd cmd;
0749         data->radio_write = 1;
0750
0751         memset(&cmd, 0, sizeof(cmd));
0752         cmd.hdr.op_code = IL_PHY_CALIBRATE_DIFF_GAIN_CMD;
0753         cmd.diff_gain_a = data->delta_gain_code[0];
0754         cmd.diff_gain_b = data->delta_gain_code[1];
0755         cmd.diff_gain_c = data->delta_gain_code[2];
0756         ret = il_send_cmd_pdu(il, C_PHY_CALIBRATION, sizeof(cmd), &cmd);
0757         if (ret)
0758             D_CALIB("fail sending cmd " "C_PHY_CALIBRATION\n");
0759
0760         /* TODO we might want recalculate
0761          * rx_chain in rxon cmd */
0762
0763         /* Mark so we run this algo only once! */
0764         data->state = IL_CHAIN_NOISE_CALIBRATED;
0765     }
0766 }
0767
0768 /*
0769  * Accumulate 16 beacons of signal and noise stats for each of
0770  *   3 receivers/antennas/rx-chains, then figure out:
0771  * 1)  Which antennas are connected.
0772  * 2)  Differential rx gain settings to balance the 3 receivers.
0773  */
0774 void
0775 il4965_chain_noise_calibration(struct il_priv *il, void *stat_resp)
0776 {
0777     struct il_chain_noise_data *data = NULL;
0778
0779     u32 chain_noise_a;
0780     u32 chain_noise_b;
0781     u32 chain_noise_c;
0782     u32 chain_sig_a;
0783     u32 chain_sig_b;
0784     u32 chain_sig_c;
0785     u32 average_sig[NUM_RX_CHAINS] = { INITIALIZATION_VALUE };
0786     u32 average_noise[NUM_RX_CHAINS] = { INITIALIZATION_VALUE };
0787     u32 min_average_noise = MIN_AVERAGE_NOISE_MAX_VALUE;
0788     u16 min_average_noise_antenna_i = INITIALIZATION_VALUE;
0789     u16 i = 0;
0790     u16 rxon_chnum = INITIALIZATION_VALUE;
0791     u16 stat_chnum = INITIALIZATION_VALUE;
0792     u8 rxon_band24;
0793     u8 stat_band24;
0794     unsigned long flags;
0795     struct stats_rx_non_phy *rx_info;
0796
0797     if (il->disable_chain_noise_cal)
0798         return;
0799
0800     data = &(il->chain_noise_data);
0801
0802     /*
0803      * Accumulate just the first "chain_noise_num_beacons" after
0804      * the first association, then we're done forever.
0805      */
0806     if (data->state != IL_CHAIN_NOISE_ACCUMULATE) {
0807         if (data->state == IL_CHAIN_NOISE_ALIVE)
0808             D_CALIB("Wait for noise calib reset\n");
0809         return;
0810     }
0811
0812     spin_lock_irqsave(&il->lock, flags);
0813
0814     rx_info = &(((struct il_notif_stats *)stat_resp)->rx.general);
0815
0816     if (rx_info->interference_data_flag != INTERFERENCE_DATA_AVAILABLE) {
0817         D_CALIB(" << Interference data unavailable\n");
0818         spin_unlock_irqrestore(&il->lock, flags);
0819         return;
0820     }
0821
0822     rxon_band24 = !!(il->staging.flags & RXON_FLG_BAND_24G_MSK);
0823     rxon_chnum = le16_to_cpu(il->staging.channel);
0824
0825     stat_band24 =
0826         !!(((struct il_notif_stats *)stat_resp)->
0827            flag & STATS_REPLY_FLG_BAND_24G_MSK);
0828     stat_chnum =
0829         le32_to_cpu(((struct il_notif_stats *)stat_resp)->flag) >> 16;
0830
0831     /* Make sure we accumulate data for just the associated channel
0832      *   (even if scanning). */
0833     if (rxon_chnum != stat_chnum || rxon_band24 != stat_band24) {
0834         D_CALIB("Stats not from chan=%d, band24=%d\n", rxon_chnum,
0835             rxon_band24);
0836         spin_unlock_irqrestore(&il->lock, flags);
0837         return;
0838     }
0839
0840     /*
0841      *  Accumulate beacon stats values across
0842      * "chain_noise_num_beacons"
0843      */
0844     chain_noise_a =
0845         le32_to_cpu(rx_info->beacon_silence_rssi_a) & IN_BAND_FILTER;
0846     chain_noise_b =
0847         le32_to_cpu(rx_info->beacon_silence_rssi_b) & IN_BAND_FILTER;
0848     chain_noise_c =
0849         le32_to_cpu(rx_info->beacon_silence_rssi_c) & IN_BAND_FILTER;
0850
0851     chain_sig_a = le32_to_cpu(rx_info->beacon_rssi_a) & IN_BAND_FILTER;
0852     chain_sig_b = le32_to_cpu(rx_info->beacon_rssi_b) & IN_BAND_FILTER;
0853     chain_sig_c = le32_to_cpu(rx_info->beacon_rssi_c) & IN_BAND_FILTER;
0854
0855     spin_unlock_irqrestore(&il->lock, flags);
0856
0857     data->beacon_count++;
0858
0859     data->chain_noise_a = (chain_noise_a + data->chain_noise_a);
0860     data->chain_noise_b = (chain_noise_b + data->chain_noise_b);
0861     data->chain_noise_c = (chain_noise_c + data->chain_noise_c);
0862
0863     data->chain_signal_a = (chain_sig_a + data->chain_signal_a);
0864     data->chain_signal_b = (chain_sig_b + data->chain_signal_b);
0865     data->chain_signal_c = (chain_sig_c + data->chain_signal_c);
0866
0867     D_CALIB("chan=%d, band24=%d, beacon=%d\n", rxon_chnum, rxon_band24,
0868         data->beacon_count);
0869     D_CALIB("chain_sig: a %d b %d c %d\n", chain_sig_a, chain_sig_b,
0870         chain_sig_c);
0871     D_CALIB("chain_noise: a %d b %d c %d\n", chain_noise_a, chain_noise_b,
0872         chain_noise_c);
0873
0874     /* If this is the "chain_noise_num_beacons", determine:
0875      * 1)  Disconnected antennas (using signal strengths)
0876      * 2)  Differential gain (using silence noise) to balance receivers */
0877     if (data->beacon_count != il->cfg->chain_noise_num_beacons)
0878         return;
0879
0880     /* Analyze signal for disconnected antenna */
0881     il4965_find_disconn_antenna(il, average_sig, data);
0882
0883     /* Analyze noise for rx balance */
0884     average_noise[0] =
0885         data->chain_noise_a / il->cfg->chain_noise_num_beacons;
0886     average_noise[1] =
0887         data->chain_noise_b / il->cfg->chain_noise_num_beacons;
0888     average_noise[2] =
0889         data->chain_noise_c / il->cfg->chain_noise_num_beacons;
0890
0891     for (i = 0; i < NUM_RX_CHAINS; i++) {
0892         if (!data->disconn_array[i] &&
0893             average_noise[i] <= min_average_noise) {
0894             /* This means that chain i is active and has
0895              * lower noise values so far: */
0896             min_average_noise = average_noise[i];
0897             min_average_noise_antenna_i = i;
0898         }
0899     }
0900
0901     D_CALIB("average_noise: a %d b %d c %d\n", average_noise[0],
0902         average_noise[1], average_noise[2]);
0903
0904     D_CALIB("min_average_noise = %d, antenna %d\n", min_average_noise,
0905         min_average_noise_antenna_i);
0906
0907     il4965_gain_computation(il, average_noise, min_average_noise_antenna_i,
0908                 min_average_noise,
0909                 il4965_find_first_chain(il->cfg->valid_rx_ant));
0910
0911     /* Some power changes may have been made during the calibration.
0912      * Update and commit the RXON
0913      */
0914     if (il->ops->update_chain_flags)
0915         il->ops->update_chain_flags(il);
0916
0917     data->state = IL_CHAIN_NOISE_DONE;
0918     il_power_update_mode(il, false);
0919 }
0920
0921 void
0922 il4965_reset_run_time_calib(struct il_priv *il)
0923 {
0924     int i;
0925     memset(&(il->sensitivity_data), 0, sizeof(struct il_sensitivity_data));
0926     memset(&(il->chain_noise_data), 0, sizeof(struct il_chain_noise_data));
0927     for (i = 0; i < NUM_RX_CHAINS; i++)
0928         il->chain_noise_data.delta_gain_code[i] =
0929             CHAIN_NOISE_DELTA_GAIN_INIT_VAL;
0930
0931     /* Ask for stats now, the uCode will send notification
0932      * periodically after association */
0933     il_send_stats_request(il, CMD_ASYNC, true);
0934 }