drivers/net/wireless/iwlwifi/mvm/rx.c

   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) 2012 - 2013 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 <ilw@linux.intel.com>
  29  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  30  *
  31  * BSD LICENSE
  32  *
  33  * Copyright(c) 2012 - 2013 Intel Corporation. All rights reserved.
  34  * All rights reserved.
  35  *
  36  * Redistribution and use in source and binary forms, with or without
  37  * modification, are permitted provided that the following conditions
  38  * are met:
  39  *
  40  *  * Redistributions of source code must retain the above copyright
  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 #include "iwl-trans.h"
  63
  64 #include "mvm.h"
  65 #include "fw-api.h"
  66
  67 /*
  68  * iwl_mvm_rx_rx_phy_cmd - REPLY_RX_PHY_CMD handler
  69  *
  70  * Copies the phy information in mvm->last_phy_info, it will be used when the
  71  * actual data will come from the fw in the next packet.
  72  */
  73 int iwl_mvm_rx_rx_phy_cmd(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb,
  74                           struct iwl_device_cmd *cmd)
  75 {
  76         struct iwl_rx_packet *pkt = rxb_addr(rxb);
  77
  78         memcpy(&mvm->last_phy_info, pkt->data, sizeof(mvm->last_phy_info));
  79         mvm->ampdu_ref++;
  80         return 0;
  81 }
  82
  83 /*
  84  * iwl_mvm_pass_packet_to_mac80211 - builds the packet for mac80211
  85  *
  86  * Adds the rxb to a new skb and give it to mac80211
  87  */
  88 static void iwl_mvm_pass_packet_to_mac80211(struct iwl_mvm *mvm,
  89                                             struct ieee80211_hdr *hdr, u16 len,
  90                                             u32 ampdu_status,
  91                                             struct iwl_rx_cmd_buffer *rxb,
  92                                             struct ieee80211_rx_status *stats)
  93 {
  94         struct sk_buff *skb;
  95         unsigned int hdrlen, fraglen;
  96
  97         /* Dont use dev_alloc_skb(), we'll have enough headroom once
  98          * ieee80211_hdr pulled.
  99          */
 100         skb = alloc_skb(128, GFP_ATOMIC);
 101         if (!skb) {
 102                 IWL_ERR(mvm, "alloc_skb failed\n");
 103                 return;
 104         }
 105         /* If frame is small enough to fit in skb->head, pull it completely.
 106          * If not, only pull ieee80211_hdr so that splice() or TCP coalesce
 107          * are more efficient.
 108          */
 109         hdrlen = (len <= skb_tailroom(skb)) ? len : sizeof(*hdr);
 110
 111         memcpy(skb_put(skb, hdrlen), hdr, hdrlen);
 112         fraglen = len - hdrlen;
 113
 114         if (fraglen) {
 115                 int offset = (void *)hdr + hdrlen -
 116                              rxb_addr(rxb) + rxb_offset(rxb);
 117
 118                 skb_add_rx_frag(skb, 0, rxb_steal_page(rxb), offset,
 119                                 fraglen, rxb->truesize);
 120         }
 121
 122         memcpy(IEEE80211_SKB_RXCB(skb), stats, sizeof(*stats));
 123
 124         ieee80211_rx_ni(mvm->hw, skb);
 125 }
 126
 127 static void iwl_mvm_calc_rssi(struct iwl_mvm *mvm,
 128                               struct iwl_rx_phy_info *phy_info,
 129                               struct ieee80211_rx_status *rx_status)
 130 {
 131         int rssi_a, rssi_b, rssi_a_dbm, rssi_b_dbm, max_rssi_dbm;
 132         int rssi_all_band_a, rssi_all_band_b;
 133         u32 agc_a, agc_b, max_agc;
 134         u32 val;
 135
 136         val = le32_to_cpu(phy_info->non_cfg_phy[IWL_RX_INFO_AGC_IDX]);
 137         agc_a = (val & IWL_OFDM_AGC_A_MSK) >> IWL_OFDM_AGC_A_POS;
 138         agc_b = (val & IWL_OFDM_AGC_B_MSK) >> IWL_OFDM_AGC_B_POS;
 139         max_agc = max_t(u32, agc_a, agc_b);
 140
 141         val = le32_to_cpu(phy_info->non_cfg_phy[IWL_RX_INFO_RSSI_AB_IDX]);
 142         rssi_a = (val & IWL_OFDM_RSSI_INBAND_A_MSK) >> IWL_OFDM_RSSI_A_POS;
 143         rssi_b = (val & IWL_OFDM_RSSI_INBAND_B_MSK) >> IWL_OFDM_RSSI_B_POS;
 144         rssi_all_band_a = (val & IWL_OFDM_RSSI_ALLBAND_A_MSK) >>
 145                                 IWL_OFDM_RSSI_ALLBAND_A_POS;
 146         rssi_all_band_b = (val & IWL_OFDM_RSSI_ALLBAND_B_MSK) >>
 147                                 IWL_OFDM_RSSI_ALLBAND_B_POS;
 148
 149         /*
 150          * dBm = rssi dB - agc dB - constant.
 151          * Higher AGC (higher radio gain) means lower signal.
 152          */
 153         rssi_a_dbm = rssi_a - IWL_RSSI_OFFSET - agc_a;
 154         rssi_b_dbm = rssi_b - IWL_RSSI_OFFSET - agc_b;
 155         max_rssi_dbm = max_t(int, rssi_a_dbm, rssi_b_dbm);
 156
 157         IWL_DEBUG_STATS(mvm, "Rssi In A %d B %d Max %d AGCA %d AGCB %d\n",
 158                         rssi_a_dbm, rssi_b_dbm, max_rssi_dbm, agc_a, agc_b);
 159
 160         rx_status->signal = max_rssi_dbm;
 161         rx_status->chains = (le16_to_cpu(phy_info->phy_flags) &
 162                                 RX_RES_PHY_FLAGS_ANTENNA)
 163                                         >> RX_RES_PHY_FLAGS_ANTENNA_POS;
 164         rx_status->chain_signal[0] = rssi_a_dbm;
 165         rx_status->chain_signal[1] = rssi_b_dbm;
 166 }
 167
 168 /*
 169  * iwl_mvm_get_signal_strength - use new rx PHY INFO API
 170  * values are reported by the fw as positive values - need to negate
 171  * to obtain their dBM.  Account for missing antennas by replacing 0
 172  * values by -256dBm: practically 0 power and a non-feasible 8 bit value.
 173  */
 174 static void iwl_mvm_get_signal_strength(struct iwl_mvm *mvm,
 175                                         struct iwl_rx_phy_info *phy_info,
 176                                         struct ieee80211_rx_status *rx_status)
 177 {
 178         int energy_a, energy_b, energy_c, max_energy;
 179         u32 val;
 180
 181         val =
 182             le32_to_cpu(phy_info->non_cfg_phy[IWL_RX_INFO_ENERGY_ANT_ABC_IDX]);
 183         energy_a = (val & IWL_RX_INFO_ENERGY_ANT_A_MSK) >>
 184                                                 IWL_RX_INFO_ENERGY_ANT_A_POS;
 185         energy_a = energy_a ? -energy_a : -256;
 186         energy_b = (val & IWL_RX_INFO_ENERGY_ANT_B_MSK) >>
 187                                                 IWL_RX_INFO_ENERGY_ANT_B_POS;
 188         energy_b = energy_b ? -energy_b : -256;
 189         energy_c = (val & IWL_RX_INFO_ENERGY_ANT_C_MSK) >>
 190                                                 IWL_RX_INFO_ENERGY_ANT_C_POS;
 191         energy_c = energy_c ? -energy_c : -256;
 192         max_energy = max(energy_a, energy_b);
 193         max_energy = max(max_energy, energy_c);
 194
 195         IWL_DEBUG_STATS(mvm, "energy In A %d B %d C %d , and max %d\n",
 196                         energy_a, energy_b, energy_c, max_energy);
 197
 198         rx_status->signal = max_energy;
 199         rx_status->chains = (le16_to_cpu(phy_info->phy_flags) &
 200                                 RX_RES_PHY_FLAGS_ANTENNA)
 201                                         >> RX_RES_PHY_FLAGS_ANTENNA_POS;
 202         rx_status->chain_signal[0] = energy_a;
 203         rx_status->chain_signal[1] = energy_b;
 204         rx_status->chain_signal[2] = energy_c;
 205 }
 206
 207 /*
 208  * iwl_mvm_set_mac80211_rx_flag - translate fw status to mac80211 format
 209  * @mvm: the mvm object
 210  * @hdr: 80211 header
 211  * @stats: status in mac80211's format
 212  * @rx_pkt_status: status coming from fw
 213  *
 214  * returns non 0 value if the packet should be dropped
 215  */
 216 static u32 iwl_mvm_set_mac80211_rx_flag(struct iwl_mvm *mvm,
 217                                         struct ieee80211_hdr *hdr,
 218                                         struct ieee80211_rx_status *stats,
 219                                         u32 rx_pkt_status)
 220 {
 221         if (!ieee80211_has_protected(hdr->frame_control) ||
 222             (rx_pkt_status & RX_MPDU_RES_STATUS_SEC_ENC_MSK) ==
 223                              RX_MPDU_RES_STATUS_SEC_NO_ENC)
 224                 return 0;
 225
 226         /* packet was encrypted with unknown alg */
 227         if ((rx_pkt_status & RX_MPDU_RES_STATUS_SEC_ENC_MSK) ==
 228                                         RX_MPDU_RES_STATUS_SEC_ENC_ERR)
 229                 return 0;
 230
 231         switch (rx_pkt_status & RX_MPDU_RES_STATUS_SEC_ENC_MSK) {
 232         case RX_MPDU_RES_STATUS_SEC_CCM_ENC:
 233                 /* alg is CCM: check MIC only */
 234                 if (!(rx_pkt_status & RX_MPDU_RES_STATUS_MIC_OK))
 235                         return -1;
 236
 237                 stats->flag |= RX_FLAG_DECRYPTED;
 238                 IWL_DEBUG_WEP(mvm, "hw decrypted CCMP successfully\n");
 239                 return 0;
 240
 241         case RX_MPDU_RES_STATUS_SEC_TKIP_ENC:
 242                 /* Don't drop the frame and decrypt it in SW */
 243                 if (!(rx_pkt_status & RX_MPDU_RES_STATUS_TTAK_OK))
 244                         return 0;
 245                 /* fall through if TTAK OK */
 246
 247         case RX_MPDU_RES_STATUS_SEC_WEP_ENC:
 248                 if (!(rx_pkt_status & RX_MPDU_RES_STATUS_ICV_OK))
 249                         return -1;
 250
 251                 stats->flag |= RX_FLAG_DECRYPTED;
 252                 return 0;
 253
 254         default:
 255                 IWL_ERR(mvm, "Unhandled alg: 0x%x\n", rx_pkt_status);
 256         }
 257
 258         return 0;
 259 }
 260
 261 /*
 262  * iwl_mvm_rx_rx_mpdu - REPLY_RX_MPDU_CMD handler
 263  *
 264  * Handles the actual data of the Rx packet from the fw
 265  */
 266 int iwl_mvm_rx_rx_mpdu(struct iwl_mvm *mvm, struct iwl_rx_cmd_buffer *rxb,
 267                        struct iwl_device_cmd *cmd)
 268 {
 269         struct ieee80211_hdr *hdr;
 270         struct ieee80211_rx_status rx_status = {};
 271         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 272         struct iwl_rx_phy_info *phy_info;
 273         struct iwl_rx_mpdu_res_start *rx_res;
 274         u32 len;
 275         u32 ampdu_status;
 276         u32 rate_n_flags;
 277         u32 rx_pkt_status;
 278
 279         phy_info = &mvm->last_phy_info;
 280         rx_res = (struct iwl_rx_mpdu_res_start *)pkt->data;
 281         hdr = (struct ieee80211_hdr *)(pkt->data + sizeof(*rx_res));
 282         len = le16_to_cpu(rx_res->byte_count);
 283         rx_pkt_status = le32_to_cpup((__le32 *)
 284                 (pkt->data + sizeof(*rx_res) + len));
 285
 286         memset(&rx_status, 0, sizeof(rx_status));
 287
 288         /*
 289          * drop the packet if it has failed being decrypted by HW
 290          */
 291         if (iwl_mvm_set_mac80211_rx_flag(mvm, hdr, &rx_status, rx_pkt_status)) {
 292                 IWL_DEBUG_DROP(mvm, "Bad decryption results 0x%08x\n",
 293                                rx_pkt_status);
 294                 return 0;
 295         }
 296
 297         if ((unlikely(phy_info->cfg_phy_cnt > 20))) {
 298                 IWL_DEBUG_DROP(mvm, "dsp size out of range [0,20]: %d\n",
 299                                phy_info->cfg_phy_cnt);
 300                 return 0;
 301         }
 302
 303         if (!(rx_pkt_status & RX_MPDU_RES_STATUS_CRC_OK) ||
 304             !(rx_pkt_status & RX_MPDU_RES_STATUS_OVERRUN_OK)) {
 305                 IWL_DEBUG_RX(mvm, "Bad CRC or FIFO: 0x%08X.\n", rx_pkt_status);
 306                 return 0;
 307         }
 308
 309         /* This will be used in several places later */
 310         rate_n_flags = le32_to_cpu(phy_info->rate_n_flags);
 311
 312         /* rx_status carries information about the packet to mac80211 */
 313         rx_status.mactime = le64_to_cpu(phy_info->timestamp);
 314         rx_status.device_timestamp = le32_to_cpu(phy_info->system_timestamp);
 315         rx_status.band =
 316                 (phy_info->phy_flags & cpu_to_le16(RX_RES_PHY_FLAGS_BAND_24)) ?
 317                                 IEEE80211_BAND_2GHZ : IEEE80211_BAND_5GHZ;
 318         rx_status.freq =
 319                 ieee80211_channel_to_frequency(le16_to_cpu(phy_info->channel),
 320                                                rx_status.band);
 321         /*
 322          * TSF as indicated by the fw is at INA time, but mac80211 expects the
 323          * TSF at the beginning of the MPDU.
 324          */
 325         /*rx_status.flag |= RX_FLAG_MACTIME_MPDU;*/
 326
 327         if (mvm->fw->ucode_capa.flags & IWL_UCODE_TLV_FLAGS_RX_ENERGY_API)
 328                 iwl_mvm_get_signal_strength(mvm, phy_info, &rx_status);
 329         else
 330                 iwl_mvm_calc_rssi(mvm, phy_info, &rx_status);
 331
 332         IWL_DEBUG_STATS_LIMIT(mvm, "Rssi %d, TSF %llu\n", rx_status.signal,
 333                               (unsigned long long)rx_status.mactime);
 334
 335         /* set the preamble flag if appropriate */
 336         if (phy_info->phy_flags & cpu_to_le16(RX_RES_PHY_FLAGS_SHORT_PREAMBLE))
 337                 rx_status.flag |= RX_FLAG_SHORTPRE;
 338
 339         if (phy_info->phy_flags & cpu_to_le16(RX_RES_PHY_FLAGS_AGG)) {
 340                 /*
 341                  * We know which subframes of an A-MPDU belong
 342                  * together since we get a single PHY response
 343                  * from the firmware for all of them
 344                  */
 345                 rx_status.flag |= RX_FLAG_AMPDU_DETAILS;
 346                 rx_status.ampdu_reference = mvm->ampdu_ref;
 347         }
 348
 349         /* Set up the HT phy flags */
 350         switch (rate_n_flags & RATE_MCS_CHAN_WIDTH_MSK) {
 351         case RATE_MCS_CHAN_WIDTH_20:
 352                 break;
 353         case RATE_MCS_CHAN_WIDTH_40:
 354                 rx_status.flag |= RX_FLAG_40MHZ;
 355                 break;
 356         case RATE_MCS_CHAN_WIDTH_80:
 357                 rx_status.flag |= RX_FLAG_80MHZ;
 358                 break;
 359         case RATE_MCS_CHAN_WIDTH_160:
 360                 rx_status.flag |= RX_FLAG_160MHZ;
 361                 break;
 362         }
 363         if (rate_n_flags & RATE_MCS_SGI_MSK)
 364                 rx_status.flag |= RX_FLAG_SHORT_GI;
 365         if (rate_n_flags & RATE_HT_MCS_GF_MSK)
 366                 rx_status.flag |= RX_FLAG_HT_GF;
 367         if (rate_n_flags & RATE_MCS_HT_MSK) {
 368                 rx_status.flag |= RX_FLAG_HT;
 369                 rx_status.rate_idx = rate_n_flags & RATE_HT_MCS_INDEX_MSK;
 370         } else if (rate_n_flags & RATE_MCS_VHT_MSK) {
 371                 rx_status.vht_nss =
 372                         ((rate_n_flags & RATE_VHT_MCS_NSS_MSK) >>
 373                                                 RATE_VHT_MCS_NSS_POS) + 1;
 374                 rx_status.rate_idx = rate_n_flags & RATE_VHT_MCS_RATE_CODE_MSK;
 375                 rx_status.flag |= RX_FLAG_VHT;
 376         } else {
 377                 rx_status.rate_idx =
 378                         iwl_mvm_legacy_rate_to_mac80211_idx(rate_n_flags,
 379                                                             rx_status.band);
 380         }
 381
 382         iwl_mvm_pass_packet_to_mac80211(mvm, hdr, len, ampdu_status,
 383                                         rxb, &rx_status);
 384         return 0;
 385 }
 386
 387 static void iwl_mvm_update_rx_statistics(struct iwl_mvm *mvm,
 388                                          struct iwl_notif_statistics *stats)
 389 {
 390         /*
 391          * NOTE FW aggregates the statistics - BUT the statistics are cleared
 392          * when the driver issues REPLY_STATISTICS_CMD 0x9c with CLEAR_STATS
 393          * bit set.
 394          */
 395         lockdep_assert_held(&mvm->mutex);
 396         memcpy(&mvm->rx_stats, &stats->rx, sizeof(struct mvm_statistics_rx));
 397 }
 398
 399 struct iwl_mvm_stat_data {
 400         struct iwl_notif_statistics *stats;
 401         struct iwl_mvm *mvm;
 402 };
 403
 404 static void iwl_mvm_stat_iterator(void *_data, u8 *mac,
 405                                   struct ieee80211_vif *vif)
 406 {
 407         struct iwl_mvm_stat_data *data = _data;
 408         struct iwl_notif_statistics *stats = data->stats;
 409         struct iwl_mvm *mvm = data->mvm;
 410         int sig = -stats->general.beacon_filter_average_energy;
 411         int last_event;
 412         int thold = vif->bss_conf.cqm_rssi_thold;
 413         int hyst = vif->bss_conf.cqm_rssi_hyst;
 414         u16 id = le32_to_cpu(stats->rx.general.mac_id);
 415         struct iwl_mvm_vif *mvmvif = iwl_mvm_vif_from_mac80211(vif);
 416
 417         if (mvmvif->id != id)
 418                 return;
 419
 420         if (vif->type != NL80211_IFTYPE_STATION)
 421                 return;
 422
 423         mvmvif->bf_data.ave_beacon_signal = sig;
 424
 425         if (!(vif->driver_flags & IEEE80211_VIF_SUPPORTS_CQM_RSSI))
 426                 return;
 427
 428         /* CQM Notification */
 429         last_event = mvmvif->bf_data.last_cqm_event;
 430         if (thold && sig < thold && (last_event == 0 ||
 431                                      sig < last_event - hyst)) {
 432                 mvmvif->bf_data.last_cqm_event = sig;
 433                 IWL_DEBUG_RX(mvm, "cqm_iterator cqm low %d\n",
 434                              sig);
 435                 ieee80211_cqm_rssi_notify(
 436                         vif,
 437                         NL80211_CQM_RSSI_THRESHOLD_EVENT_LOW,
 438                         GFP_KERNEL);
 439         } else if (sig > thold &&
 440                    (last_event == 0 || sig > last_event + hyst)) {
 441                 mvmvif->bf_data.last_cqm_event = sig;
 442                 IWL_DEBUG_RX(mvm, "cqm_iterator cqm high %d\n",
 443                              sig);
 444                 ieee80211_cqm_rssi_notify(
 445                         vif,
 446                         NL80211_CQM_RSSI_THRESHOLD_EVENT_HIGH,
 447                         GFP_KERNEL);
 448         }
 449 }
 450
 451 /*
 452  * iwl_mvm_rx_statistics - STATISTICS_NOTIFICATION handler
 453  *
 454  * TODO: This handler is implemented partially.
 455  */
 456 int iwl_mvm_rx_statistics(struct iwl_mvm *mvm,
 457                           struct iwl_rx_cmd_buffer *rxb,
 458                           struct iwl_device_cmd *cmd)
 459 {
 460         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 461         struct iwl_notif_statistics *stats = (void *)&pkt->data;
 462         struct mvm_statistics_general_common *common = &stats->general.common;
 463         struct iwl_mvm_stat_data data = {
 464                 .stats = stats,
 465                 .mvm = mvm,
 466         };
 467
 468         if (mvm->temperature != le32_to_cpu(common->temperature)) {
 469                 mvm->temperature = le32_to_cpu(common->temperature);
 470                 iwl_mvm_tt_handler(mvm);
 471         }
 472         iwl_mvm_update_rx_statistics(mvm, stats);
 473
 474         ieee80211_iterate_active_interfaces(mvm->hw,
 475                                             IEEE80211_IFACE_ITER_NORMAL,
 476                                             iwl_mvm_stat_iterator,
 477                                             &data);
 478         return 0;
 479 }