drivers/net/wireless/iwlwifi/iwl-rx.c

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2003 - 2008 Intel Corporation. All rights reserved.
   4  *
   5  * Portions of this file are derived from the ipw3945 project, as well
   6  * as portions of the ieee80211 subsystem header files.
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of version 2 of the GNU General Public License as
  10  * published by the Free Software Foundation.
  11  *
  12  * This program is distributed in the hope that it will be useful, but WITHOUT
  13  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  15  * more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along with
  18  * this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110, USA
  20  *
  21  * The full GNU General Public License is included in this distribution in the
  22  * file called LICENSE.
  23  *
  24  * Contact Information:
  25  * James P. Ketrenos <ipw2100-admin@linux.intel.com>
  26  * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
  27  *
  28  *****************************************************************************/
  29
  30 #include <linux/etherdevice.h>
  31 #include <net/mac80211.h>
  32 #include "iwl-eeprom.h"
  33 #include "iwl-dev.h"
  34 #include "iwl-core.h"
  35 #include "iwl-sta.h"
  36 #include "iwl-io.h"
  37 #include "iwl-calib.h"
  38 #include "iwl-helpers.h"
  39 /************************** RX-FUNCTIONS ****************************/
  40 /*
  41  * Rx theory of operation
  42  *
  43  * Driver allocates a circular buffer of Receive Buffer Descriptors (RBDs),
  44  * each of which point to Receive Buffers to be filled by the NIC.  These get
  45  * used not only for Rx frames, but for any command response or notification
  46  * from the NIC.  The driver and NIC manage the Rx buffers by means
  47  * of indexes into the circular buffer.
  48  *
  49  * Rx Queue Indexes
  50  * The host/firmware share two index registers for managing the Rx buffers.
  51  *
  52  * The READ index maps to the first position that the firmware may be writing
  53  * to -- the driver can read up to (but not including) this position and get
  54  * good data.
  55  * The READ index is managed by the firmware once the card is enabled.
  56  *
  57  * The WRITE index maps to the last position the driver has read from -- the
  58  * position preceding WRITE is the last slot the firmware can place a packet.
  59  *
  60  * The queue is empty (no good data) if WRITE = READ - 1, and is full if
  61  * WRITE = READ.
  62  *
  63  * During initialization, the host sets up the READ queue position to the first
  64  * INDEX position, and WRITE to the last (READ - 1 wrapped)
  65  *
  66  * When the firmware places a packet in a buffer, it will advance the READ index
  67  * and fire the RX interrupt.  The driver can then query the READ index and
  68  * process as many packets as possible, moving the WRITE index forward as it
  69  * resets the Rx queue buffers with new memory.
  70  *
  71  * The management in the driver is as follows:
  72  * + A list of pre-allocated SKBs is stored in iwl->rxq->rx_free.  When
  73  *   iwl->rxq->free_count drops to or below RX_LOW_WATERMARK, work is scheduled
  74  *   to replenish the iwl->rxq->rx_free.
  75  * + In iwl_rx_replenish (scheduled) if 'processed' != 'read' then the
  76  *   iwl->rxq is replenished and the READ INDEX is updated (updating the
  77  *   'processed' and 'read' driver indexes as well)
  78  * + A received packet is processed and handed to the kernel network stack,
  79  *   detached from the iwl->rxq.  The driver 'processed' index is updated.
  80  * + The Host/Firmware iwl->rxq is replenished at tasklet time from the rx_free
  81  *   list. If there are no allocated buffers in iwl->rxq->rx_free, the READ
  82  *   INDEX is not incremented and iwl->status(RX_STALLED) is set.  If there
  83  *   were enough free buffers and RX_STALLED is set it is cleared.
  84  *
  85  *
  86  * Driver sequence:
  87  *
  88  * iwl_rx_queue_alloc()   Allocates rx_free
  89  * iwl_rx_replenish()     Replenishes rx_free list from rx_used, and calls
  90  *                            iwl_rx_queue_restock
  91  * iwl_rx_queue_restock() Moves available buffers from rx_free into Rx
  92  *                            queue, updates firmware pointers, and updates
  93  *                            the WRITE index.  If insufficient rx_free buffers
  94  *                            are available, schedules iwl_rx_replenish
  95  *
  96  * -- enable interrupts --
  97  * ISR - iwl_rx()         Detach iwl_rx_mem_buffers from pool up to the
  98  *                            READ INDEX, detaching the SKB from the pool.
  99  *                            Moves the packet buffer from queue to rx_used.
 100  *                            Calls iwl_rx_queue_restock to refill any empty
 101  *                            slots.
 102  * ...
 103  *
 104  */
 105
 106 /**
 107  * iwl_rx_queue_space - Return number of free slots available in queue.
 108  */
 109 int iwl_rx_queue_space(const struct iwl_rx_queue *q)
 110 {
 111         int s = q->read - q->write;
 112         if (s <= 0)
 113                 s += RX_QUEUE_SIZE;
 114         /* keep some buffer to not confuse full and empty queue */
 115         s -= 2;
 116         if (s < 0)
 117                 s = 0;
 118         return s;
 119 }
 120 EXPORT_SYMBOL(iwl_rx_queue_space);
 121
 122 /**
 123  * iwl_rx_queue_update_write_ptr - Update the write pointer for the RX queue
 124  */
 125 int iwl_rx_queue_update_write_ptr(struct iwl_priv *priv, struct iwl_rx_queue *q)
 126 {
 127         u32 reg = 0;
 128         int ret = 0;
 129         unsigned long flags;
 130
 131         spin_lock_irqsave(&q->lock, flags);
 132
 133         if (q->need_update == 0)
 134                 goto exit_unlock;
 135
 136         /* If power-saving is in use, make sure device is awake */
 137         if (test_bit(STATUS_POWER_PMI, &priv->status)) {
 138                 reg = iwl_read32(priv, CSR_UCODE_DRV_GP1);
 139
 140                 if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
 141                         iwl_set_bit(priv, CSR_GP_CNTRL,
 142                                     CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
 143                         goto exit_unlock;
 144                 }
 145
 146                 ret = iwl_grab_nic_access(priv);
 147                 if (ret)
 148                         goto exit_unlock;
 149
 150                 /* Device expects a multiple of 8 */
 151                 iwl_write_direct32(priv, FH_RSCSR_CHNL0_WPTR,
 152                                      q->write & ~0x7);
 153                 iwl_release_nic_access(priv);
 154
 155         /* Else device is assumed to be awake */
 156         } else
 157                 /* Device expects a multiple of 8 */
 158                 iwl_write32(priv, FH_RSCSR_CHNL0_WPTR, q->write & ~0x7);
 159
 160
 161         q->need_update = 0;
 162
 163  exit_unlock:
 164         spin_unlock_irqrestore(&q->lock, flags);
 165         return ret;
 166 }
 167 EXPORT_SYMBOL(iwl_rx_queue_update_write_ptr);
 168 /**
 169  * iwl_dma_addr2rbd_ptr - convert a DMA address to a uCode read buffer ptr
 170  */
 171 static inline __le32 iwl_dma_addr2rbd_ptr(struct iwl_priv *priv,
 172                                           dma_addr_t dma_addr)
 173 {
 174         return cpu_to_le32((u32)(dma_addr >> 8));
 175 }
 176
 177 /**
 178  * iwl_rx_queue_restock - refill RX queue from pre-allocated pool
 179  *
 180  * If there are slots in the RX queue that need to be restocked,
 181  * and we have free pre-allocated buffers, fill the ranks as much
 182  * as we can, pulling from rx_free.
 183  *
 184  * This moves the 'write' index forward to catch up with 'processed', and
 185  * also updates the memory address in the firmware to reference the new
 186  * target buffer.
 187  */
 188 int iwl_rx_queue_restock(struct iwl_priv *priv)
 189 {
 190         struct iwl_rx_queue *rxq = &priv->rxq;
 191         struct list_head *element;
 192         struct iwl_rx_mem_buffer *rxb;
 193         unsigned long flags;
 194         int write;
 195         int ret = 0;
 196
 197         spin_lock_irqsave(&rxq->lock, flags);
 198         write = rxq->write & ~0x7;
 199         while ((iwl_rx_queue_space(rxq) > 0) && (rxq->free_count)) {
 200                 /* Get next free Rx buffer, remove from free list */
 201                 element = rxq->rx_free.next;
 202                 rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
 203                 list_del(element);
 204
 205                 /* Point to Rx buffer via next RBD in circular buffer */
 206                 rxq->bd[rxq->write] = iwl_dma_addr2rbd_ptr(priv, rxb->dma_addr);
 207                 rxq->queue[rxq->write] = rxb;
 208                 rxq->write = (rxq->write + 1) & RX_QUEUE_MASK;
 209                 rxq->free_count--;
 210         }
 211         spin_unlock_irqrestore(&rxq->lock, flags);
 212         /* If the pre-allocated buffer pool is dropping low, schedule to
 213          * refill it */
 214         if (rxq->free_count <= RX_LOW_WATERMARK)
 215                 queue_work(priv->workqueue, &priv->rx_replenish);
 216
 217
 218         /* If we've added more space for the firmware to place data, tell it.
 219          * Increment device's write pointer in multiples of 8. */
 220         if ((write != (rxq->write & ~0x7))
 221             || (abs(rxq->write - rxq->read) > 7)) {
 222                 spin_lock_irqsave(&rxq->lock, flags);
 223                 rxq->need_update = 1;
 224                 spin_unlock_irqrestore(&rxq->lock, flags);
 225                 ret = iwl_rx_queue_update_write_ptr(priv, rxq);
 226         }
 227
 228         return ret;
 229 }
 230 EXPORT_SYMBOL(iwl_rx_queue_restock);
 231
 232
 233 /**
 234  * iwl_rx_replenish - Move all used packet from rx_used to rx_free
 235  *
 236  * When moving to rx_free an SKB is allocated for the slot.
 237  *
 238  * Also restock the Rx queue via iwl_rx_queue_restock.
 239  * This is called as a scheduled work item (except for during initialization)
 240  */
 241 void iwl_rx_allocate(struct iwl_priv *priv)
 242 {
 243         struct iwl_rx_queue *rxq = &priv->rxq;
 244         struct list_head *element;
 245         struct iwl_rx_mem_buffer *rxb;
 246         unsigned long flags;
 247         spin_lock_irqsave(&rxq->lock, flags);
 248         while (!list_empty(&rxq->rx_used)) {
 249                 element = rxq->rx_used.next;
 250                 rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
 251
 252                 /* Alloc a new receive buffer */
 253                 rxb->skb = alloc_skb(priv->hw_params.rx_buf_size,
 254                                 __GFP_NOWARN | GFP_ATOMIC);
 255                 if (!rxb->skb) {
 256                         if (net_ratelimit())
 257                                 printk(KERN_CRIT DRV_NAME
 258                                        ": Can not allocate SKB buffers\n");
 259                         /* We don't reschedule replenish work here -- we will
 260                          * call the restock method and if it still needs
 261                          * more buffers it will schedule replenish */
 262                         break;
 263                 }
 264                 priv->alloc_rxb_skb++;
 265                 list_del(element);
 266
 267                 /* Get physical address of RB/SKB */
 268                 rxb->dma_addr =
 269                     pci_map_single(priv->pci_dev, rxb->skb->data,
 270                            priv->hw_params.rx_buf_size, PCI_DMA_FROMDEVICE);
 271                 list_add_tail(&rxb->list, &rxq->rx_free);
 272                 rxq->free_count++;
 273         }
 274         spin_unlock_irqrestore(&rxq->lock, flags);
 275 }
 276 EXPORT_SYMBOL(iwl_rx_allocate);
 277
 278 void iwl_rx_replenish(struct iwl_priv *priv)
 279 {
 280         unsigned long flags;
 281
 282         iwl_rx_allocate(priv);
 283
 284         spin_lock_irqsave(&priv->lock, flags);
 285         iwl_rx_queue_restock(priv);
 286         spin_unlock_irqrestore(&priv->lock, flags);
 287 }
 288 EXPORT_SYMBOL(iwl_rx_replenish);
 289
 290
 291 /* Assumes that the skb field of the buffers in 'pool' is kept accurate.
 292  * If an SKB has been detached, the POOL needs to have its SKB set to NULL
 293  * This free routine walks the list of POOL entries and if SKB is set to
 294  * non NULL it is unmapped and freed
 295  */
 296 void iwl_rx_queue_free(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
 297 {
 298         int i;
 299         for (i = 0; i < RX_QUEUE_SIZE + RX_FREE_BUFFERS; i++) {
 300                 if (rxq->pool[i].skb != NULL) {
 301                         pci_unmap_single(priv->pci_dev,
 302                                          rxq->pool[i].dma_addr,
 303                                          priv->hw_params.rx_buf_size,
 304                                          PCI_DMA_FROMDEVICE);
 305                         dev_kfree_skb(rxq->pool[i].skb);
 306                 }
 307         }
 308
 309         pci_free_consistent(priv->pci_dev, 4 * RX_QUEUE_SIZE, rxq->bd,
 310                             rxq->dma_addr);
 311         rxq->bd = NULL;
 312 }
 313 EXPORT_SYMBOL(iwl_rx_queue_free);
 314
 315 int iwl_rx_queue_alloc(struct iwl_priv *priv)
 316 {
 317         struct iwl_rx_queue *rxq = &priv->rxq;
 318         struct pci_dev *dev = priv->pci_dev;
 319         int i;
 320
 321         spin_lock_init(&rxq->lock);
 322         INIT_LIST_HEAD(&rxq->rx_free);
 323         INIT_LIST_HEAD(&rxq->rx_used);
 324
 325         /* Alloc the circular buffer of Read Buffer Descriptors (RBDs) */
 326         rxq->bd = pci_alloc_consistent(dev, 4 * RX_QUEUE_SIZE, &rxq->dma_addr);
 327         if (!rxq->bd)
 328                 return -ENOMEM;
 329
 330         /* Fill the rx_used queue with _all_ of the Rx buffers */
 331         for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++)
 332                 list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
 333
 334         /* Set us so that we have processed and used all buffers, but have
 335          * not restocked the Rx queue with fresh buffers */
 336         rxq->read = rxq->write = 0;
 337         rxq->free_count = 0;
 338         rxq->need_update = 0;
 339         return 0;
 340 }
 341 EXPORT_SYMBOL(iwl_rx_queue_alloc);
 342
 343 void iwl_rx_queue_reset(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
 344 {
 345         unsigned long flags;
 346         int i;
 347         spin_lock_irqsave(&rxq->lock, flags);
 348         INIT_LIST_HEAD(&rxq->rx_free);
 349         INIT_LIST_HEAD(&rxq->rx_used);
 350         /* Fill the rx_used queue with _all_ of the Rx buffers */
 351         for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++) {
 352                 /* In the reset function, these buffers may have been allocated
 353                  * to an SKB, so we need to unmap and free potential storage */
 354                 if (rxq->pool[i].skb != NULL) {
 355                         pci_unmap_single(priv->pci_dev,
 356                                          rxq->pool[i].dma_addr,
 357                                          priv->hw_params.rx_buf_size,
 358                                          PCI_DMA_FROMDEVICE);
 359                         priv->alloc_rxb_skb--;
 360                         dev_kfree_skb(rxq->pool[i].skb);
 361                         rxq->pool[i].skb = NULL;
 362                 }
 363                 list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
 364         }
 365
 366         /* Set us so that we have processed and used all buffers, but have
 367          * not restocked the Rx queue with fresh buffers */
 368         rxq->read = rxq->write = 0;
 369         rxq->free_count = 0;
 370         spin_unlock_irqrestore(&rxq->lock, flags);
 371 }
 372 EXPORT_SYMBOL(iwl_rx_queue_reset);
 373
 374 int iwl_rx_init(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
 375 {
 376         int ret;
 377         unsigned long flags;
 378         unsigned int rb_size;
 379
 380         spin_lock_irqsave(&priv->lock, flags);
 381         ret = iwl_grab_nic_access(priv);
 382         if (ret) {
 383                 spin_unlock_irqrestore(&priv->lock, flags);
 384                 return ret;
 385         }
 386
 387         if (priv->cfg->mod_params->amsdu_size_8K)
 388                 rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_8K;
 389         else
 390                 rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K;
 391
 392         /* Stop Rx DMA */
 393         iwl_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
 394
 395         /* Reset driver's Rx queue write index */
 396         iwl_write_direct32(priv, FH_RSCSR_CHNL0_RBDCB_WPTR_REG, 0);
 397
 398         /* Tell device where to find RBD circular buffer in DRAM */
 399         iwl_write_direct32(priv, FH_RSCSR_CHNL0_RBDCB_BASE_REG,
 400                            rxq->dma_addr >> 8);
 401
 402         /* Tell device where in DRAM to update its Rx status */
 403         iwl_write_direct32(priv, FH_RSCSR_CHNL0_STTS_WPTR_REG,
 404                            (priv->shared_phys + priv->rb_closed_offset) >> 4);
 405
 406         /* Enable Rx DMA, enable host interrupt, Rx buffer size 4k, 256 RBDs */
 407         iwl_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG,
 408                            FH_RCSR_RX_CONFIG_CHNL_EN_ENABLE_VAL |
 409                            FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_INT_HOST_VAL |
 410                            rb_size |
 411                              /* 0x10 << 4 | */
 412                            (RX_QUEUE_SIZE_LOG <<
 413                               FH_RCSR_RX_CONFIG_RBDCB_SIZE_BITSHIFT));
 414
 415         /*
 416          * iwl_write32(priv,CSR_INT_COAL_REG,0);
 417          */
 418
 419         iwl_release_nic_access(priv);
 420         spin_unlock_irqrestore(&priv->lock, flags);
 421
 422         return 0;
 423 }
 424
 425 int iwl_rxq_stop(struct iwl_priv *priv)
 426 {
 427         int ret;
 428         unsigned long flags;
 429
 430         spin_lock_irqsave(&priv->lock, flags);
 431         ret = iwl_grab_nic_access(priv);
 432         if (unlikely(ret)) {
 433                 spin_unlock_irqrestore(&priv->lock, flags);
 434                 return ret;
 435         }
 436
 437         /* stop Rx DMA */
 438         iwl_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
 439         ret = iwl_poll_direct_bit(priv, FH_MEM_RSSR_RX_STATUS_REG,
 440                                      (1 << 24), 1000);
 441         if (ret < 0)
 442                 IWL_ERROR("Can't stop Rx DMA.\n");
 443
 444         iwl_release_nic_access(priv);
 445         spin_unlock_irqrestore(&priv->lock, flags);
 446
 447         return 0;
 448 }
 449 EXPORT_SYMBOL(iwl_rxq_stop);
 450
 451 void iwl_rx_missed_beacon_notif(struct iwl_priv *priv,
 452                                 struct iwl_rx_mem_buffer *rxb)
 453
 454 {
 455         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
 456         struct iwl4965_missed_beacon_notif *missed_beacon;
 457
 458         missed_beacon = &pkt->u.missed_beacon;
 459         if (le32_to_cpu(missed_beacon->consequtive_missed_beacons) > 5) {
 460                 IWL_DEBUG_CALIB("missed bcn cnsq %d totl %d rcd %d expctd %d\n",
 461                     le32_to_cpu(missed_beacon->consequtive_missed_beacons),
 462                     le32_to_cpu(missed_beacon->total_missed_becons),
 463                     le32_to_cpu(missed_beacon->num_recvd_beacons),
 464                     le32_to_cpu(missed_beacon->num_expected_beacons));
 465                 if (!test_bit(STATUS_SCANNING, &priv->status))
 466                         iwl_init_sensitivity(priv);
 467         }
 468 }
 469 EXPORT_SYMBOL(iwl_rx_missed_beacon_notif);
 470
 471 int iwl_rx_agg_start(struct iwl_priv *priv, const u8 *addr, int tid, u16 ssn)
 472 {
 473         unsigned long flags;
 474         int sta_id;
 475
 476         sta_id = iwl_find_station(priv, addr);
 477         if (sta_id == IWL_INVALID_STATION)
 478                 return -ENXIO;
 479
 480         spin_lock_irqsave(&priv->sta_lock, flags);
 481         priv->stations[sta_id].sta.station_flags_msk = 0;
 482         priv->stations[sta_id].sta.sta.modify_mask = STA_MODIFY_ADDBA_TID_MSK;
 483         priv->stations[sta_id].sta.add_immediate_ba_tid = (u8)tid;
 484         priv->stations[sta_id].sta.add_immediate_ba_ssn = cpu_to_le16(ssn);
 485         priv->stations[sta_id].sta.mode = STA_CONTROL_MODIFY_MSK;
 486         spin_unlock_irqrestore(&priv->sta_lock, flags);
 487
 488         return iwl_send_add_sta(priv, &priv->stations[sta_id].sta,
 489                                         CMD_ASYNC);
 490 }
 491 EXPORT_SYMBOL(iwl_rx_agg_start);
 492
 493 int iwl_rx_agg_stop(struct iwl_priv *priv, const u8 *addr, int tid)
 494 {
 495         unsigned long flags;
 496         int sta_id;
 497
 498         sta_id = iwl_find_station(priv, addr);
 499         if (sta_id == IWL_INVALID_STATION)
 500                 return -ENXIO;
 501
 502         spin_lock_irqsave(&priv->sta_lock, flags);
 503         priv->stations[sta_id].sta.station_flags_msk = 0;
 504         priv->stations[sta_id].sta.sta.modify_mask = STA_MODIFY_DELBA_TID_MSK;
 505         priv->stations[sta_id].sta.remove_immediate_ba_tid = (u8)tid;
 506         priv->stations[sta_id].sta.mode = STA_CONTROL_MODIFY_MSK;
 507         spin_unlock_irqrestore(&priv->sta_lock, flags);
 508
 509         return iwl_send_add_sta(priv, &priv->stations[sta_id].sta,
 510                                         CMD_ASYNC);
 511 }
 512 EXPORT_SYMBOL(iwl_rx_agg_stop);
 513
 514
 515 /* Calculate noise level, based on measurements during network silence just
 516  *   before arriving beacon.  This measurement can be done only if we know
 517  *   exactly when to expect beacons, therefore only when we're associated. */
 518 static void iwl_rx_calc_noise(struct iwl_priv *priv)
 519 {
 520         struct statistics_rx_non_phy *rx_info
 521                                 = &(priv->statistics.rx.general);
 522         int num_active_rx = 0;
 523         int total_silence = 0;
 524         int bcn_silence_a =
 525                 le32_to_cpu(rx_info->beacon_silence_rssi_a) & IN_BAND_FILTER;
 526         int bcn_silence_b =
 527                 le32_to_cpu(rx_info->beacon_silence_rssi_b) & IN_BAND_FILTER;
 528         int bcn_silence_c =
 529                 le32_to_cpu(rx_info->beacon_silence_rssi_c) & IN_BAND_FILTER;
 530
 531         if (bcn_silence_a) {
 532                 total_silence += bcn_silence_a;
 533                 num_active_rx++;
 534         }
 535         if (bcn_silence_b) {
 536                 total_silence += bcn_silence_b;
 537                 num_active_rx++;
 538         }
 539         if (bcn_silence_c) {
 540                 total_silence += bcn_silence_c;
 541                 num_active_rx++;
 542         }
 543
 544         /* Average among active antennas */
 545         if (num_active_rx)
 546                 priv->last_rx_noise = (total_silence / num_active_rx) - 107;
 547         else
 548                 priv->last_rx_noise = IWL_NOISE_MEAS_NOT_AVAILABLE;
 549
 550         IWL_DEBUG_CALIB("inband silence a %u, b %u, c %u, dBm %d\n",
 551                         bcn_silence_a, bcn_silence_b, bcn_silence_c,
 552                         priv->last_rx_noise);
 553 }
 554
 555 #define REG_RECALIB_PERIOD (60)
 556
 557 void iwl_rx_statistics(struct iwl_priv *priv,
 558                               struct iwl_rx_mem_buffer *rxb)
 559 {
 560         int change;
 561         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
 562
 563         IWL_DEBUG_RX("Statistics notification received (%d vs %d).\n",
 564                      (int)sizeof(priv->statistics), pkt->len);
 565
 566         change = ((priv->statistics.general.temperature !=
 567                    pkt->u.stats.general.temperature) ||
 568                   ((priv->statistics.flag &
 569                     STATISTICS_REPLY_FLG_FAT_MODE_MSK) !=
 570                    (pkt->u.stats.flag & STATISTICS_REPLY_FLG_FAT_MODE_MSK)));
 571
 572         memcpy(&priv->statistics, &pkt->u.stats, sizeof(priv->statistics));
 573
 574         set_bit(STATUS_STATISTICS, &priv->status);
 575
 576         /* Reschedule the statistics timer to occur in
 577          * REG_RECALIB_PERIOD seconds to ensure we get a
 578          * thermal update even if the uCode doesn't give
 579          * us one */
 580         mod_timer(&priv->statistics_periodic, jiffies +
 581                   msecs_to_jiffies(REG_RECALIB_PERIOD * 1000));
 582
 583         if (unlikely(!test_bit(STATUS_SCANNING, &priv->status)) &&
 584             (pkt->hdr.cmd == STATISTICS_NOTIFICATION)) {
 585                 iwl_rx_calc_noise(priv);
 586                 queue_work(priv->workqueue, &priv->run_time_calib_work);
 587         }
 588
 589         iwl_leds_background(priv);
 590
 591         if (priv->cfg->ops->lib->temperature && change)
 592                 priv->cfg->ops->lib->temperature(priv);
 593 }
 594 EXPORT_SYMBOL(iwl_rx_statistics);
 595
 596 #define PERFECT_RSSI (-20) /* dBm */
 597 #define WORST_RSSI (-95)   /* dBm */
 598 #define RSSI_RANGE (PERFECT_RSSI - WORST_RSSI)
 599
 600 /* Calculate an indication of rx signal quality (a percentage, not dBm!).
 601  * See http://www.ces.clemson.edu/linux/signal_quality.shtml for info
 602  *   about formulas used below. */
 603 static int iwl_calc_sig_qual(int rssi_dbm, int noise_dbm)
 604 {
 605         int sig_qual;
 606         int degradation = PERFECT_RSSI - rssi_dbm;
 607
 608         /* If we get a noise measurement, use signal-to-noise ratio (SNR)
 609          * as indicator; formula is (signal dbm - noise dbm).
 610          * SNR at or above 40 is a great signal (100%).
 611          * Below that, scale to fit SNR of 0 - 40 dB within 0 - 100% indicator.
 612          * Weakest usable signal is usually 10 - 15 dB SNR. */
 613         if (noise_dbm) {
 614                 if (rssi_dbm - noise_dbm >= 40)
 615                         return 100;
 616                 else if (rssi_dbm < noise_dbm)
 617                         return 0;
 618                 sig_qual = ((rssi_dbm - noise_dbm) * 5) / 2;
 619
 620         /* Else use just the signal level.
 621          * This formula is a least squares fit of data points collected and
 622          *   compared with a reference system that had a percentage (%) display
 623          *   for signal quality. */
 624         } else
 625                 sig_qual = (100 * (RSSI_RANGE * RSSI_RANGE) - degradation *
 626                             (15 * RSSI_RANGE + 62 * degradation)) /
 627                            (RSSI_RANGE * RSSI_RANGE);
 628
 629         if (sig_qual > 100)
 630                 sig_qual = 100;
 631         else if (sig_qual < 1)
 632                 sig_qual = 0;
 633
 634         return sig_qual;
 635 }
 636
 637 #ifdef CONFIG_IWLWIFI_DEBUG
 638
 639 /**
 640  * iwl_dbg_report_frame - dump frame to syslog during debug sessions
 641  *
 642  * You may hack this function to show different aspects of received frames,
 643  * including selective frame dumps.
 644  * group100 parameter selects whether to show 1 out of 100 good frames.
 645  *
 646  * TODO:  This was originally written for 3945, need to audit for
 647  *        proper operation with 4965.
 648  */
 649 static void iwl_dbg_report_frame(struct iwl_priv *priv,
 650                       struct iwl_rx_packet *pkt,
 651                       struct ieee80211_hdr *header, int group100)
 652 {
 653         u32 to_us;
 654         u32 print_summary = 0;
 655         u32 print_dump = 0;     /* set to 1 to dump all frames' contents */
 656         u32 hundred = 0;
 657         u32 dataframe = 0;
 658         __le16 fc;
 659         u16 seq_ctl;
 660         u16 channel;
 661         u16 phy_flags;
 662         int rate_sym;
 663         u16 length;
 664         u16 status;
 665         u16 bcn_tmr;
 666         u32 tsf_low;
 667         u64 tsf;
 668         u8 rssi;
 669         u8 agc;
 670         u16 sig_avg;
 671         u16 noise_diff;
 672         struct iwl4965_rx_frame_stats *rx_stats = IWL_RX_STATS(pkt);
 673         struct iwl4965_rx_frame_hdr *rx_hdr = IWL_RX_HDR(pkt);
 674         struct iwl4965_rx_frame_end *rx_end = IWL_RX_END(pkt);
 675         u8 *data = IWL_RX_DATA(pkt);
 676
 677         if (likely(!(priv->debug_level & IWL_DL_RX)))
 678                 return;
 679
 680         /* MAC header */
 681         fc = header->frame_control;
 682         seq_ctl = le16_to_cpu(header->seq_ctrl);
 683
 684         /* metadata */
 685         channel = le16_to_cpu(rx_hdr->channel);
 686         phy_flags = le16_to_cpu(rx_hdr->phy_flags);
 687         rate_sym = rx_hdr->rate;
 688         length = le16_to_cpu(rx_hdr->len);
 689
 690         /* end-of-frame status and timestamp */
 691         status = le32_to_cpu(rx_end->status);
 692         bcn_tmr = le32_to_cpu(rx_end->beacon_timestamp);
 693         tsf_low = le64_to_cpu(rx_end->timestamp) & 0x0ffffffff;
 694         tsf = le64_to_cpu(rx_end->timestamp);
 695
 696         /* signal statistics */
 697         rssi = rx_stats->rssi;
 698         agc = rx_stats->agc;
 699         sig_avg = le16_to_cpu(rx_stats->sig_avg);
 700         noise_diff = le16_to_cpu(rx_stats->noise_diff);
 701
 702         to_us = !compare_ether_addr(header->addr1, priv->mac_addr);
 703
 704         /* if data frame is to us and all is good,
 705          *   (optionally) print summary for only 1 out of every 100 */
 706         if (to_us && (fc & ~cpu_to_le16(IEEE80211_FCTL_PROTECTED)) ==
 707             cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FTYPE_DATA)) {
 708                 dataframe = 1;
 709                 if (!group100)
 710                         print_summary = 1;      /* print each frame */
 711                 else if (priv->framecnt_to_us < 100) {
 712                         priv->framecnt_to_us++;
 713                         print_summary = 0;
 714                 } else {
 715                         priv->framecnt_to_us = 0;
 716                         print_summary = 1;
 717                         hundred = 1;
 718                 }
 719         } else {
 720                 /* print summary for all other frames */
 721                 print_summary = 1;
 722         }
 723
 724         if (print_summary) {
 725                 char *title;
 726                 int rate_idx;
 727                 u32 bitrate;
 728
 729                 if (hundred)
 730                         title = "100Frames";
 731                 else if (ieee80211_has_retry(fc))
 732                         title = "Retry";
 733                 else if (ieee80211_is_assoc_resp(fc))
 734                         title = "AscRsp";
 735                 else if (ieee80211_is_reassoc_resp(fc))
 736                         title = "RasRsp";
 737                 else if (ieee80211_is_probe_resp(fc)) {
 738                         title = "PrbRsp";
 739                         print_dump = 1; /* dump frame contents */
 740                 } else if (ieee80211_is_beacon(fc)) {
 741                         title = "Beacon";
 742                         print_dump = 1; /* dump frame contents */
 743                 } else if (ieee80211_is_atim(fc))
 744                         title = "ATIM";
 745                 else if (ieee80211_is_auth(fc))
 746                         title = "Auth";
 747                 else if (ieee80211_is_deauth(fc))
 748                         title = "DeAuth";
 749                 else if (ieee80211_is_disassoc(fc))
 750                         title = "DisAssoc";
 751                 else
 752                         title = "Frame";
 753
 754                 rate_idx = iwl_hwrate_to_plcp_idx(rate_sym);
 755                 if (unlikely(rate_idx == -1))
 756                         bitrate = 0;
 757                 else
 758                         bitrate = iwl_rates[rate_idx].ieee / 2;
 759
 760                 /* print frame summary.
 761                  * MAC addresses show just the last byte (for brevity),
 762                  *    but you can hack it to show more, if you'd like to. */
 763                 if (dataframe)
 764                         IWL_DEBUG_RX("%s: mhd=0x%04x, dst=0x%02x, "
 765                                      "len=%u, rssi=%d, chnl=%d, rate=%u, \n",
 766                                      title, le16_to_cpu(fc), header->addr1[5],
 767                                      length, rssi, channel, bitrate);
 768                 else {
 769                         /* src/dst addresses assume managed mode */
 770                         IWL_DEBUG_RX("%s: 0x%04x, dst=0x%02x, "
 771                                      "src=0x%02x, rssi=%u, tim=%lu usec, "
 772                                      "phy=0x%02x, chnl=%d\n",
 773                                      title, le16_to_cpu(fc), header->addr1[5],
 774                                      header->addr3[5], rssi,
 775                                      tsf_low - priv->scan_start_tsf,
 776                                      phy_flags, channel);
 777                 }
 778         }
 779         if (print_dump)
 780                 iwl_print_hex_dump(priv, IWL_DL_RX, data, length);
 781 }
 782 #else
 783 static inline void iwl_dbg_report_frame(struct iwl_priv *priv,
 784                                             struct iwl_rx_packet *pkt,
 785                                             struct ieee80211_hdr *header,
 786                                             int group100)
 787 {
 788 }
 789 #endif
 790
 791 static void iwl_add_radiotap(struct iwl_priv *priv,
 792                                  struct sk_buff *skb,
 793                                  struct iwl4965_rx_phy_res *rx_start,
 794                                  struct ieee80211_rx_status *stats,
 795                                  u32 ampdu_status)
 796 {
 797         s8 signal = stats->signal;
 798         s8 noise = 0;
 799         int rate = stats->rate_idx;
 800         u64 tsf = stats->mactime;
 801         __le16 antenna;
 802         __le16 phy_flags_hw = rx_start->phy_flags;
 803         struct iwl4965_rt_rx_hdr {
 804                 struct ieee80211_radiotap_header rt_hdr;
 805                 __le64 rt_tsf;          /* TSF */
 806                 u8 rt_flags;            /* radiotap packet flags */
 807                 u8 rt_rate;             /* rate in 500kb/s */
 808                 __le16 rt_channelMHz;   /* channel in MHz */
 809                 __le16 rt_chbitmask;    /* channel bitfield */
 810                 s8 rt_dbmsignal;        /* signal in dBm, kluged to signed */
 811                 s8 rt_dbmnoise;
 812                 u8 rt_antenna;          /* antenna number */
 813         } __attribute__ ((packed)) *iwl4965_rt;
 814
 815         /* TODO: We won't have enough headroom for HT frames. Fix it later. */
 816         if (skb_headroom(skb) < sizeof(*iwl4965_rt)) {
 817                 if (net_ratelimit())
 818                         printk(KERN_ERR "not enough headroom [%d] for "
 819                                "radiotap head [%zd]\n",
 820                                skb_headroom(skb), sizeof(*iwl4965_rt));
 821                 return;
 822         }
 823
 824         /* put radiotap header in front of 802.11 header and data */
 825         iwl4965_rt = (void *)skb_push(skb, sizeof(*iwl4965_rt));
 826
 827         /* initialise radiotap header */
 828         iwl4965_rt->rt_hdr.it_version = PKTHDR_RADIOTAP_VERSION;
 829         iwl4965_rt->rt_hdr.it_pad = 0;
 830
 831         /* total header + data */
 832         put_unaligned(cpu_to_le16(sizeof(*iwl4965_rt)),
 833                       &iwl4965_rt->rt_hdr.it_len);
 834
 835         /* Indicate all the fields we add to the radiotap header */
 836         put_unaligned(cpu_to_le32((1 << IEEE80211_RADIOTAP_TSFT) |
 837                                   (1 << IEEE80211_RADIOTAP_FLAGS) |
 838                                   (1 << IEEE80211_RADIOTAP_RATE) |
 839                                   (1 << IEEE80211_RADIOTAP_CHANNEL) |
 840                                   (1 << IEEE80211_RADIOTAP_DBM_ANTSIGNAL) |
 841                                   (1 << IEEE80211_RADIOTAP_DBM_ANTNOISE) |
 842                                   (1 << IEEE80211_RADIOTAP_ANTENNA)),
 843                       &iwl4965_rt->rt_hdr.it_present);
 844
 845         /* Zero the flags, we'll add to them as we go */
 846         iwl4965_rt->rt_flags = 0;
 847
 848         put_unaligned(cpu_to_le64(tsf), &iwl4965_rt->rt_tsf);
 849
 850         iwl4965_rt->rt_dbmsignal = signal;
 851         iwl4965_rt->rt_dbmnoise = noise;
 852
 853         /* Convert the channel frequency and set the flags */
 854         put_unaligned(cpu_to_le16(stats->freq), &iwl4965_rt->rt_channelMHz);
 855         if (!(phy_flags_hw & RX_RES_PHY_FLAGS_BAND_24_MSK))
 856                 put_unaligned(cpu_to_le16(IEEE80211_CHAN_OFDM |
 857                                           IEEE80211_CHAN_5GHZ),
 858                               &iwl4965_rt->rt_chbitmask);
 859         else if (phy_flags_hw & RX_RES_PHY_FLAGS_MOD_CCK_MSK)
 860                 put_unaligned(cpu_to_le16(IEEE80211_CHAN_CCK |
 861                                           IEEE80211_CHAN_2GHZ),
 862                               &iwl4965_rt->rt_chbitmask);
 863         else    /* 802.11g */
 864                 put_unaligned(cpu_to_le16(IEEE80211_CHAN_OFDM |
 865                                           IEEE80211_CHAN_2GHZ),
 866                               &iwl4965_rt->rt_chbitmask);
 867
 868         if (rate == -1)
 869                 iwl4965_rt->rt_rate = 0;
 870         else
 871                 iwl4965_rt->rt_rate = iwl_rates[rate].ieee;
 872
 873         /*
 874          * "antenna number"
 875          *
 876          * It seems that the antenna field in the phy flags value
 877          * is actually a bitfield. This is undefined by radiotap,
 878          * it wants an actual antenna number but I always get "7"
 879          * for most legacy frames I receive indicating that the
 880          * same frame was received on all three RX chains.
 881          *
 882          * I think this field should be removed in favour of a
 883          * new 802.11n radiotap field "RX chains" that is defined
 884          * as a bitmask.
 885          */
 886         antenna = phy_flags_hw & RX_RES_PHY_FLAGS_ANTENNA_MSK;
 887         iwl4965_rt->rt_antenna = le16_to_cpu(antenna) >> 4;
 888
 889         /* set the preamble flag if appropriate */
 890         if (phy_flags_hw & RX_RES_PHY_FLAGS_SHORT_PREAMBLE_MSK)
 891                 iwl4965_rt->rt_flags |= IEEE80211_RADIOTAP_F_SHORTPRE;
 892
 893         stats->flag |= RX_FLAG_RADIOTAP;
 894 }
 895
 896 static void iwl_update_rx_stats(struct iwl_priv *priv, u16 fc, u16 len)
 897 {
 898         /* 0 - mgmt, 1 - cnt, 2 - data */
 899         int idx = (fc & IEEE80211_FCTL_FTYPE) >> 2;
 900         priv->rx_stats[idx].cnt++;
 901         priv->rx_stats[idx].bytes += len;
 902 }
 903
 904 /*
 905  * returns non-zero if packet should be dropped
 906  */
 907 static int iwl_set_decrypted_flag(struct iwl_priv *priv,
 908                                       struct ieee80211_hdr *hdr,
 909                                       u32 decrypt_res,
 910                                       struct ieee80211_rx_status *stats)
 911 {
 912         u16 fc = le16_to_cpu(hdr->frame_control);
 913
 914         if (priv->active_rxon.filter_flags & RXON_FILTER_DIS_DECRYPT_MSK)
 915                 return 0;
 916
 917         if (!(fc & IEEE80211_FCTL_PROTECTED))
 918                 return 0;
 919
 920         IWL_DEBUG_RX("decrypt_res:0x%x\n", decrypt_res);
 921         switch (decrypt_res & RX_RES_STATUS_SEC_TYPE_MSK) {
 922         case RX_RES_STATUS_SEC_TYPE_TKIP:
 923                 /* The uCode has got a bad phase 1 Key, pushes the packet.
 924                  * Decryption will be done in SW. */
 925                 if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
 926                     RX_RES_STATUS_BAD_KEY_TTAK)
 927                         break;
 928
 929         case RX_RES_STATUS_SEC_TYPE_WEP:
 930                 if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
 931                     RX_RES_STATUS_BAD_ICV_MIC) {
 932                         /* bad ICV, the packet is destroyed since the
 933                          * decryption is inplace, drop it */
 934                         IWL_DEBUG_RX("Packet destroyed\n");
 935                         return -1;
 936                 }
 937         case RX_RES_STATUS_SEC_TYPE_CCMP:
 938                 if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
 939                     RX_RES_STATUS_DECRYPT_OK) {
 940                         IWL_DEBUG_RX("hw decrypt successfully!!!\n");
 941                         stats->flag |= RX_FLAG_DECRYPTED;
 942                 }
 943                 break;
 944
 945         default:
 946                 break;
 947         }
 948         return 0;
 949 }
 950
 951 static u32 iwl_translate_rx_status(struct iwl_priv *priv, u32 decrypt_in)
 952 {
 953         u32 decrypt_out = 0;
 954
 955         if ((decrypt_in & RX_RES_STATUS_STATION_FOUND) ==
 956                                         RX_RES_STATUS_STATION_FOUND)
 957                 decrypt_out |= (RX_RES_STATUS_STATION_FOUND |
 958                                 RX_RES_STATUS_NO_STATION_INFO_MISMATCH);
 959
 960         decrypt_out |= (decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK);
 961
 962         /* packet was not encrypted */
 963         if ((decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) ==
 964                                         RX_RES_STATUS_SEC_TYPE_NONE)
 965                 return decrypt_out;
 966
 967         /* packet was encrypted with unknown alg */
 968         if ((decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) ==
 969                                         RX_RES_STATUS_SEC_TYPE_ERR)
 970                 return decrypt_out;
 971
 972         /* decryption was not done in HW */
 973         if ((decrypt_in & RX_MPDU_RES_STATUS_DEC_DONE_MSK) !=
 974                                         RX_MPDU_RES_STATUS_DEC_DONE_MSK)
 975                 return decrypt_out;
 976
 977         switch (decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) {
 978
 979         case RX_RES_STATUS_SEC_TYPE_CCMP:
 980                 /* alg is CCM: check MIC only */
 981                 if (!(decrypt_in & RX_MPDU_RES_STATUS_MIC_OK))
 982                         /* Bad MIC */
 983                         decrypt_out |= RX_RES_STATUS_BAD_ICV_MIC;
 984                 else
 985                         decrypt_out |= RX_RES_STATUS_DECRYPT_OK;
 986
 987                 break;
 988
 989         case RX_RES_STATUS_SEC_TYPE_TKIP:
 990                 if (!(decrypt_in & RX_MPDU_RES_STATUS_TTAK_OK)) {
 991                         /* Bad TTAK */
 992                         decrypt_out |= RX_RES_STATUS_BAD_KEY_TTAK;
 993                         break;
 994                 }
 995                 /* fall through if TTAK OK */
 996         default:
 997                 if (!(decrypt_in & RX_MPDU_RES_STATUS_ICV_OK))
 998                         decrypt_out |= RX_RES_STATUS_BAD_ICV_MIC;
 999                 else
1000                         decrypt_out |= RX_RES_STATUS_DECRYPT_OK;
1001                 break;
1002         };
1003
1004         IWL_DEBUG_RX("decrypt_in:0x%x  decrypt_out = 0x%x\n",
1005                                         decrypt_in, decrypt_out);
1006
1007         return decrypt_out;
1008 }
1009
1010 static void iwl_pass_packet_to_mac80211(struct iwl_priv *priv,
1011                                        int include_phy,
1012                                        struct iwl_rx_mem_buffer *rxb,
1013                                        struct ieee80211_rx_status *stats)
1014 {
1015         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
1016         struct iwl4965_rx_phy_res *rx_start = (include_phy) ?
1017             (struct iwl4965_rx_phy_res *)&(pkt->u.raw[0]) : NULL;
1018         struct ieee80211_hdr *hdr;
1019         u16 len;
1020         __le32 *rx_end;
1021         unsigned int skblen;
1022         u32 ampdu_status;
1023         u32 ampdu_status_legacy;
1024
1025         if (!include_phy && priv->last_phy_res[0])
1026                 rx_start = (struct iwl4965_rx_phy_res *)&priv->last_phy_res[1];
1027
1028         if (!rx_start) {
1029                 IWL_ERROR("MPDU frame without a PHY data\n");
1030                 return;
1031         }
1032         if (include_phy) {
1033                 hdr = (struct ieee80211_hdr *)((u8 *) &rx_start[1] +
1034                                                rx_start->cfg_phy_cnt);
1035
1036                 len = le16_to_cpu(rx_start->byte_count);
1037
1038                 rx_end = (__le32 *) ((u8 *) &pkt->u.raw[0] +
1039                                   sizeof(struct iwl4965_rx_phy_res) +
1040                                   rx_start->cfg_phy_cnt + len);
1041
1042         } else {
1043                 struct iwl4965_rx_mpdu_res_start *amsdu =
1044                     (struct iwl4965_rx_mpdu_res_start *)pkt->u.raw;
1045
1046                 hdr = (struct ieee80211_hdr *)(pkt->u.raw +
1047                                sizeof(struct iwl4965_rx_mpdu_res_start));
1048                 len =  le16_to_cpu(amsdu->byte_count);
1049                 rx_start->byte_count = amsdu->byte_count;
1050                 rx_end = (__le32 *) (((u8 *) hdr) + len);
1051         }
1052
1053         ampdu_status = le32_to_cpu(*rx_end);
1054         skblen = ((u8 *) rx_end - (u8 *) &pkt->u.raw[0]) + sizeof(u32);
1055
1056         if (!include_phy) {
1057                 /* New status scheme, need to translate */
1058                 ampdu_status_legacy = ampdu_status;
1059                 ampdu_status = iwl_translate_rx_status(priv, ampdu_status);
1060         }
1061
1062         /* start from MAC */
1063         skb_reserve(rxb->skb, (void *)hdr - (void *)pkt);
1064         skb_put(rxb->skb, len); /* end where data ends */
1065
1066         /* We only process data packets if the interface is open */
1067         if (unlikely(!priv->is_open)) {
1068                 IWL_DEBUG_DROP_LIMIT
1069                     ("Dropping packet while interface is not open.\n");
1070                 return;
1071         }
1072
1073         hdr = (struct ieee80211_hdr *)rxb->skb->data;
1074
1075         /*  in case of HW accelerated crypto and bad decryption, drop */
1076         if (!priv->hw_params.sw_crypto &&
1077             iwl_set_decrypted_flag(priv, hdr, ampdu_status, stats))
1078                 return;
1079
1080         if (priv->add_radiotap)
1081                 iwl_add_radiotap(priv, rxb->skb, rx_start, stats, ampdu_status);
1082
1083         iwl_update_rx_stats(priv, le16_to_cpu(hdr->frame_control), len);
1084         ieee80211_rx_irqsafe(priv->hw, rxb->skb, stats);
1085         priv->alloc_rxb_skb--;
1086         rxb->skb = NULL;
1087 }
1088
1089 /* Calc max signal level (dBm) among 3 possible receivers */
1090 static int iwl_calc_rssi(struct iwl_priv *priv,
1091                              struct iwl4965_rx_phy_res *rx_resp)
1092 {
1093         /* data from PHY/DSP regarding signal strength, etc.,
1094          *   contents are always there, not configurable by host.  */
1095         struct iwl4965_rx_non_cfg_phy *ncphy =
1096             (struct iwl4965_rx_non_cfg_phy *)rx_resp->non_cfg_phy;
1097         u32 agc = (le16_to_cpu(ncphy->agc_info) & IWL_AGC_DB_MASK)
1098                         >> IWL_AGC_DB_POS;
1099
1100         u32 valid_antennae =
1101             (le16_to_cpu(rx_resp->phy_flags) & RX_PHY_FLAGS_ANTENNAE_MASK)
1102                         >> RX_PHY_FLAGS_ANTENNAE_OFFSET;
1103         u8 max_rssi = 0;
1104         u32 i;
1105
1106         /* Find max rssi among 3 possible receivers.
1107          * These values are measured by the digital signal processor (DSP).
1108          * They should stay fairly constant even as the signal strength varies,
1109          *   if the radio's automatic gain control (AGC) is working right.
1110          * AGC value (see below) will provide the "interesting" info. */
1111         for (i = 0; i < 3; i++)
1112                 if (valid_antennae & (1 << i))
1113                         max_rssi = max(ncphy->rssi_info[i << 1], max_rssi);
1114
1115         IWL_DEBUG_STATS("Rssi In A %d B %d C %d Max %d AGC dB %d\n",
1116                 ncphy->rssi_info[0], ncphy->rssi_info[2], ncphy->rssi_info[4],
1117                 max_rssi, agc);
1118
1119         /* dBm = max_rssi dB - agc dB - constant.
1120          * Higher AGC (higher radio gain) means lower signal. */
1121         return max_rssi - agc - IWL_RSSI_OFFSET;
1122 }
1123
1124 static void iwl_sta_modify_ps_wake(struct iwl_priv *priv, int sta_id)
1125 {
1126         unsigned long flags;
1127
1128         spin_lock_irqsave(&priv->sta_lock, flags);
1129         priv->stations[sta_id].sta.station_flags &= ~STA_FLG_PWR_SAVE_MSK;
1130         priv->stations[sta_id].sta.station_flags_msk = STA_FLG_PWR_SAVE_MSK;
1131         priv->stations[sta_id].sta.sta.modify_mask = 0;
1132         priv->stations[sta_id].sta.mode = STA_CONTROL_MODIFY_MSK;
1133         spin_unlock_irqrestore(&priv->sta_lock, flags);
1134
1135         iwl_send_add_sta(priv, &priv->stations[sta_id].sta, CMD_ASYNC);
1136 }
1137
1138 static void iwl_update_ps_mode(struct iwl_priv *priv, u16 ps_bit, u8 *addr)
1139 {
1140         /* FIXME: need locking over ps_status ??? */
1141         u8 sta_id = iwl_find_station(priv, addr);
1142
1143         if (sta_id != IWL_INVALID_STATION) {
1144                 u8 sta_awake = priv->stations[sta_id].
1145                                 ps_status == STA_PS_STATUS_WAKE;
1146
1147                 if (sta_awake && ps_bit)
1148                         priv->stations[sta_id].ps_status = STA_PS_STATUS_SLEEP;
1149                 else if (!sta_awake && !ps_bit) {
1150                         iwl_sta_modify_ps_wake(priv, sta_id);
1151                         priv->stations[sta_id].ps_status = STA_PS_STATUS_WAKE;
1152                 }
1153         }
1154 }
1155
1156 /* This is necessary only for a number of statistics, see the caller. */
1157 static int iwl_is_network_packet(struct iwl_priv *priv,
1158                 struct ieee80211_hdr *header)
1159 {
1160         /* Filter incoming packets to determine if they are targeted toward
1161          * this network, discarding packets coming from ourselves */
1162         switch (priv->iw_mode) {
1163         case IEEE80211_IF_TYPE_IBSS: /* Header: Dest. | Source    | BSSID */
1164                 /* packets to our IBSS update information */
1165                 return !compare_ether_addr(header->addr3, priv->bssid);
1166         case IEEE80211_IF_TYPE_STA: /* Header: Dest. | AP{BSSID} | Source */
1167                 /* packets to our IBSS update information */
1168                 return !compare_ether_addr(header->addr2, priv->bssid);
1169         default:
1170                 return 1;
1171         }
1172 }
1173
1174 /* Called for REPLY_RX (legacy ABG frames), or
1175  * REPLY_RX_MPDU_CMD (HT high-throughput N frames). */
1176 void iwl_rx_reply_rx(struct iwl_priv *priv,
1177                                 struct iwl_rx_mem_buffer *rxb)
1178 {
1179         struct ieee80211_hdr *header;
1180         struct ieee80211_rx_status rx_status;
1181         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
1182         /* Use phy data (Rx signal strength, etc.) contained within
1183          *   this rx packet for legacy frames,
1184          *   or phy data cached from REPLY_RX_PHY_CMD for HT frames. */
1185         int include_phy = (pkt->hdr.cmd == REPLY_RX);
1186         struct iwl4965_rx_phy_res *rx_start = (include_phy) ?
1187                 (struct iwl4965_rx_phy_res *)&(pkt->u.raw[0]) :
1188                 (struct iwl4965_rx_phy_res *)&priv->last_phy_res[1];
1189         __le32 *rx_end;
1190         unsigned int len = 0;
1191         u16 fc;
1192         u8 network_packet;
1193
1194         rx_status.mactime = le64_to_cpu(rx_start->timestamp);
1195         rx_status.freq =
1196                 ieee80211_channel_to_frequency(le16_to_cpu(rx_start->channel));
1197         rx_status.band = (rx_start->phy_flags & RX_RES_PHY_FLAGS_BAND_24_MSK) ?
1198                                 IEEE80211_BAND_2GHZ : IEEE80211_BAND_5GHZ;
1199         rx_status.rate_idx =
1200                 iwl_hwrate_to_plcp_idx(le32_to_cpu(rx_start->rate_n_flags));
1201         if (rx_status.band == IEEE80211_BAND_5GHZ)
1202                 rx_status.rate_idx -= IWL_FIRST_OFDM_RATE;
1203
1204         rx_status.antenna = 0;
1205         rx_status.flag = 0;
1206         rx_status.flag |= RX_FLAG_TSFT;
1207
1208         if ((unlikely(rx_start->cfg_phy_cnt > 20))) {
1209                 IWL_DEBUG_DROP("dsp size out of range [0,20]: %d/n",
1210                                 rx_start->cfg_phy_cnt);
1211                 return;
1212         }
1213
1214         if (!include_phy) {
1215                 if (priv->last_phy_res[0])
1216                         rx_start = (struct iwl4965_rx_phy_res *)
1217                                 &priv->last_phy_res[1];
1218                 else
1219                         rx_start = NULL;
1220         }
1221
1222         if (!rx_start) {
1223                 IWL_ERROR("MPDU frame without a PHY data\n");
1224                 return;
1225         }
1226
1227         if (include_phy) {
1228                 header = (struct ieee80211_hdr *)((u8 *) &rx_start[1]
1229                                                   + rx_start->cfg_phy_cnt);
1230
1231                 len = le16_to_cpu(rx_start->byte_count);
1232                 rx_end = (__le32 *)(pkt->u.raw + rx_start->cfg_phy_cnt +
1233                                   sizeof(struct iwl4965_rx_phy_res) + len);
1234         } else {
1235                 struct iwl4965_rx_mpdu_res_start *amsdu =
1236                         (struct iwl4965_rx_mpdu_res_start *)pkt->u.raw;
1237
1238                 header = (void *)(pkt->u.raw +
1239                         sizeof(struct iwl4965_rx_mpdu_res_start));
1240                 len = le16_to_cpu(amsdu->byte_count);
1241                 rx_end = (__le32 *) (pkt->u.raw +
1242                         sizeof(struct iwl4965_rx_mpdu_res_start) + len);
1243         }
1244
1245         if (!(*rx_end & RX_RES_STATUS_NO_CRC32_ERROR) ||
1246             !(*rx_end & RX_RES_STATUS_NO_RXE_OVERFLOW)) {
1247                 IWL_DEBUG_RX("Bad CRC or FIFO: 0x%08X.\n",
1248                                 le32_to_cpu(*rx_end));
1249                 return;
1250         }
1251
1252         priv->ucode_beacon_time = le32_to_cpu(rx_start->beacon_time_stamp);
1253
1254         /* Find max signal strength (dBm) among 3 antenna/receiver chains */
1255         rx_status.signal = iwl_calc_rssi(priv, rx_start);
1256
1257         /* Meaningful noise values are available only from beacon statistics,
1258          *   which are gathered only when associated, and indicate noise
1259          *   only for the associated network channel ...
1260          * Ignore these noise values while scanning (other channels) */
1261         if (iwl_is_associated(priv) &&
1262             !test_bit(STATUS_SCANNING, &priv->status)) {
1263                 rx_status.noise = priv->last_rx_noise;
1264                 rx_status.qual = iwl_calc_sig_qual(rx_status.signal,
1265                                                          rx_status.noise);
1266         } else {
1267                 rx_status.noise = IWL_NOISE_MEAS_NOT_AVAILABLE;
1268                 rx_status.qual = iwl_calc_sig_qual(rx_status.signal, 0);
1269         }
1270
1271         /* Reset beacon noise level if not associated. */
1272         if (!iwl_is_associated(priv))
1273                 priv->last_rx_noise = IWL_NOISE_MEAS_NOT_AVAILABLE;
1274
1275         /* Set "1" to report good data frames in groups of 100 */
1276         /* FIXME: need to optimze the call: */
1277         iwl_dbg_report_frame(priv, pkt, header, 1);
1278
1279         IWL_DEBUG_STATS_LIMIT("Rssi %d, noise %d, qual %d, TSF %llu\n",
1280                 rx_status.signal, rx_status.noise, rx_status.signal,
1281                 (unsigned long long)rx_status.mactime);
1282
1283         /* Take shortcut when only in monitor mode */
1284         if (priv->iw_mode == IEEE80211_IF_TYPE_MNTR) {
1285                 iwl_pass_packet_to_mac80211(priv, include_phy,
1286                                                  rxb, &rx_status);
1287                 return;
1288         }
1289
1290         network_packet = iwl_is_network_packet(priv, header);
1291         if (network_packet) {
1292                 priv->last_rx_rssi = rx_status.signal;
1293                 priv->last_beacon_time =  priv->ucode_beacon_time;
1294                 priv->last_tsf = le64_to_cpu(rx_start->timestamp);
1295         }
1296
1297         fc = le16_to_cpu(header->frame_control);
1298         switch (fc & IEEE80211_FCTL_FTYPE) {
1299         case IEEE80211_FTYPE_MGMT:
1300         case IEEE80211_FTYPE_DATA:
1301                 if (priv->iw_mode == IEEE80211_IF_TYPE_AP)
1302                         iwl_update_ps_mode(priv, fc  & IEEE80211_FCTL_PM,
1303                                                 header->addr2);
1304                 /* fall through */
1305         default:
1306                         iwl_pass_packet_to_mac80211(priv, include_phy, rxb,
1307                                    &rx_status);
1308                 break;
1309
1310         }
1311 }
1312 EXPORT_SYMBOL(iwl_rx_reply_rx);
1313
1314 /* Cache phy data (Rx signal strength, etc) for HT frame (REPLY_RX_PHY_CMD).
1315  * This will be used later in iwl_rx_reply_rx() for REPLY_RX_MPDU_CMD. */
1316 void iwl_rx_reply_rx_phy(struct iwl_priv *priv,
1317                                     struct iwl_rx_mem_buffer *rxb)
1318 {
1319         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
1320         priv->last_phy_res[0] = 1;
1321         memcpy(&priv->last_phy_res[1], &(pkt->u.raw[0]),
1322                sizeof(struct iwl4965_rx_phy_res));
1323 }
1324 EXPORT_SYMBOL(iwl_rx_reply_rx_phy);