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

   1 /******************************************************************************
   2  *
   3  * Copyright(c) 2003 - 2010 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  *  Intel Linux Wireless <ilw@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 <asm/unaligned.h>
  33 #include "iwl-eeprom.h"
  34 #include "iwl-dev.h"
  35 #include "iwl-core.h"
  36 #include "iwl-sta.h"
  37 #include "iwl-io.h"
  38 #include "iwl-calib.h"
  39 #include "iwl-helpers.h"
  40 /************************** RX-FUNCTIONS ****************************/
  41 /*
  42  * Rx theory of operation
  43  *
  44  * Driver allocates a circular buffer of Receive Buffer Descriptors (RBDs),
  45  * each of which point to Receive Buffers to be filled by the NIC.  These get
  46  * used not only for Rx frames, but for any command response or notification
  47  * from the NIC.  The driver and NIC manage the Rx buffers by means
  48  * of indexes into the circular buffer.
  49  *
  50  * Rx Queue Indexes
  51  * The host/firmware share two index registers for managing the Rx buffers.
  52  *
  53  * The READ index maps to the first position that the firmware may be writing
  54  * to -- the driver can read up to (but not including) this position and get
  55  * good data.
  56  * The READ index is managed by the firmware once the card is enabled.
  57  *
  58  * The WRITE index maps to the last position the driver has read from -- the
  59  * position preceding WRITE is the last slot the firmware can place a packet.
  60  *
  61  * The queue is empty (no good data) if WRITE = READ - 1, and is full if
  62  * WRITE = READ.
  63  *
  64  * During initialization, the host sets up the READ queue position to the first
  65  * INDEX position, and WRITE to the last (READ - 1 wrapped)
  66  *
  67  * When the firmware places a packet in a buffer, it will advance the READ index
  68  * and fire the RX interrupt.  The driver can then query the READ index and
  69  * process as many packets as possible, moving the WRITE index forward as it
  70  * resets the Rx queue buffers with new memory.
  71  *
  72  * The management in the driver is as follows:
  73  * + A list of pre-allocated SKBs is stored in iwl->rxq->rx_free.  When
  74  *   iwl->rxq->free_count drops to or below RX_LOW_WATERMARK, work is scheduled
  75  *   to replenish the iwl->rxq->rx_free.
  76  * + In iwl_rx_replenish (scheduled) if 'processed' != 'read' then the
  77  *   iwl->rxq is replenished and the READ INDEX is updated (updating the
  78  *   'processed' and 'read' driver indexes as well)
  79  * + A received packet is processed and handed to the kernel network stack,
  80  *   detached from the iwl->rxq.  The driver 'processed' index is updated.
  81  * + The Host/Firmware iwl->rxq is replenished at tasklet time from the rx_free
  82  *   list. If there are no allocated buffers in iwl->rxq->rx_free, the READ
  83  *   INDEX is not incremented and iwl->status(RX_STALLED) is set.  If there
  84  *   were enough free buffers and RX_STALLED is set it is cleared.
  85  *
  86  *
  87  * Driver sequence:
  88  *
  89  * iwl_rx_queue_alloc()   Allocates rx_free
  90  * iwl_rx_replenish()     Replenishes rx_free list from rx_used, and calls
  91  *                            iwl_rx_queue_restock
  92  * iwl_rx_queue_restock() Moves available buffers from rx_free into Rx
  93  *                            queue, updates firmware pointers, and updates
  94  *                            the WRITE index.  If insufficient rx_free buffers
  95  *                            are available, schedules iwl_rx_replenish
  96  *
  97  * -- enable interrupts --
  98  * ISR - iwl_rx()         Detach iwl_rx_mem_buffers from pool up to the
  99  *                            READ INDEX, detaching the SKB from the pool.
 100  *                            Moves the packet buffer from queue to rx_used.
 101  *                            Calls iwl_rx_queue_restock to refill any empty
 102  *                            slots.
 103  * ...
 104  *
 105  */
 106
 107 /**
 108  * iwl_rx_queue_space - Return number of free slots available in queue.
 109  */
 110 int iwl_rx_queue_space(const struct iwl_rx_queue *q)
 111 {
 112         int s = q->read - q->write;
 113         if (s <= 0)
 114                 s += RX_QUEUE_SIZE;
 115         /* keep some buffer to not confuse full and empty queue */
 116         s -= 2;
 117         if (s < 0)
 118                 s = 0;
 119         return s;
 120 }
 121 EXPORT_SYMBOL(iwl_rx_queue_space);
 122
 123 /**
 124  * iwl_rx_queue_update_write_ptr - Update the write pointer for the RX queue
 125  */
 126 void iwl_rx_queue_update_write_ptr(struct iwl_priv *priv, struct iwl_rx_queue *q)
 127 {
 128         unsigned long flags;
 129         u32 rx_wrt_ptr_reg = priv->hw_params.rx_wrt_ptr_reg;
 130         u32 reg;
 131
 132         spin_lock_irqsave(&q->lock, flags);
 133
 134         if (q->need_update == 0)
 135                 goto exit_unlock;
 136
 137         /* If power-saving is in use, make sure device is awake */
 138         if (test_bit(STATUS_POWER_PMI, &priv->status)) {
 139                 reg = iwl_read32(priv, CSR_UCODE_DRV_GP1);
 140
 141                 if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
 142                         IWL_DEBUG_INFO(priv, "Rx queue requesting wakeup, GP1 = 0x%x\n",
 143                                       reg);
 144                         iwl_set_bit(priv, CSR_GP_CNTRL,
 145                                     CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
 146                         goto exit_unlock;
 147                 }
 148
 149                 q->write_actual = (q->write & ~0x7);
 150                 iwl_write_direct32(priv, rx_wrt_ptr_reg, q->write_actual);
 151
 152         /* Else device is assumed to be awake */
 153         } else {
 154                 /* Device expects a multiple of 8 */
 155                 q->write_actual = (q->write & ~0x7);
 156                 iwl_write_direct32(priv, rx_wrt_ptr_reg, q->write_actual);
 157         }
 158
 159         q->need_update = 0;
 160
 161  exit_unlock:
 162         spin_unlock_irqrestore(&q->lock, flags);
 163 }
 164 EXPORT_SYMBOL(iwl_rx_queue_update_write_ptr);
 165 /**
 166  * iwl_dma_addr2rbd_ptr - convert a DMA address to a uCode read buffer ptr
 167  */
 168 static inline __le32 iwl_dma_addr2rbd_ptr(struct iwl_priv *priv,
 169                                           dma_addr_t dma_addr)
 170 {
 171         return cpu_to_le32((u32)(dma_addr >> 8));
 172 }
 173
 174 /**
 175  * iwl_rx_queue_restock - refill RX queue from pre-allocated pool
 176  *
 177  * If there are slots in the RX queue that need to be restocked,
 178  * and we have free pre-allocated buffers, fill the ranks as much
 179  * as we can, pulling from rx_free.
 180  *
 181  * This moves the 'write' index forward to catch up with 'processed', and
 182  * also updates the memory address in the firmware to reference the new
 183  * target buffer.
 184  */
 185 void iwl_rx_queue_restock(struct iwl_priv *priv)
 186 {
 187         struct iwl_rx_queue *rxq = &priv->rxq;
 188         struct list_head *element;
 189         struct iwl_rx_mem_buffer *rxb;
 190         unsigned long flags;
 191         int write;
 192
 193         spin_lock_irqsave(&rxq->lock, flags);
 194         write = rxq->write & ~0x7;
 195         while ((iwl_rx_queue_space(rxq) > 0) && (rxq->free_count)) {
 196                 /* Get next free Rx buffer, remove from free list */
 197                 element = rxq->rx_free.next;
 198                 rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
 199                 list_del(element);
 200
 201                 /* Point to Rx buffer via next RBD in circular buffer */
 202                 rxq->bd[rxq->write] = iwl_dma_addr2rbd_ptr(priv, rxb->page_dma);
 203                 rxq->queue[rxq->write] = rxb;
 204                 rxq->write = (rxq->write + 1) & RX_QUEUE_MASK;
 205                 rxq->free_count--;
 206         }
 207         spin_unlock_irqrestore(&rxq->lock, flags);
 208         /* If the pre-allocated buffer pool is dropping low, schedule to
 209          * refill it */
 210         if (rxq->free_count <= RX_LOW_WATERMARK)
 211                 queue_work(priv->workqueue, &priv->rx_replenish);
 212
 213
 214         /* If we've added more space for the firmware to place data, tell it.
 215          * Increment device's write pointer in multiples of 8. */
 216         if (rxq->write_actual != (rxq->write & ~0x7)) {
 217                 spin_lock_irqsave(&rxq->lock, flags);
 218                 rxq->need_update = 1;
 219                 spin_unlock_irqrestore(&rxq->lock, flags);
 220                 iwl_rx_queue_update_write_ptr(priv, rxq);
 221         }
 222 }
 223 EXPORT_SYMBOL(iwl_rx_queue_restock);
 224
 225
 226 /**
 227  * iwl_rx_replenish - Move all used packet from rx_used to rx_free
 228  *
 229  * When moving to rx_free an SKB is allocated for the slot.
 230  *
 231  * Also restock the Rx queue via iwl_rx_queue_restock.
 232  * This is called as a scheduled work item (except for during initialization)
 233  */
 234 void iwl_rx_allocate(struct iwl_priv *priv, gfp_t priority)
 235 {
 236         struct iwl_rx_queue *rxq = &priv->rxq;
 237         struct list_head *element;
 238         struct iwl_rx_mem_buffer *rxb;
 239         struct page *page;
 240         unsigned long flags;
 241         gfp_t gfp_mask = priority;
 242
 243         while (1) {
 244                 spin_lock_irqsave(&rxq->lock, flags);
 245                 if (list_empty(&rxq->rx_used)) {
 246                         spin_unlock_irqrestore(&rxq->lock, flags);
 247                         return;
 248                 }
 249                 spin_unlock_irqrestore(&rxq->lock, flags);
 250
 251                 if (rxq->free_count > RX_LOW_WATERMARK)
 252                         gfp_mask |= __GFP_NOWARN;
 253
 254                 if (priv->hw_params.rx_page_order > 0)
 255                         gfp_mask |= __GFP_COMP;
 256
 257                 /* Alloc a new receive buffer */
 258                 page = alloc_pages(gfp_mask, priv->hw_params.rx_page_order);
 259                 if (!page) {
 260                         if (net_ratelimit())
 261                                 IWL_DEBUG_INFO(priv, "alloc_pages failed, "
 262                                                "order: %d\n",
 263                                                priv->hw_params.rx_page_order);
 264
 265                         if ((rxq->free_count <= RX_LOW_WATERMARK) &&
 266                             net_ratelimit())
 267                                 IWL_CRIT(priv, "Failed to alloc_pages with %s. Only %u free buffers remaining.\n",
 268                                          priority == GFP_ATOMIC ?  "GFP_ATOMIC" : "GFP_KERNEL",
 269                                          rxq->free_count);
 270                         /* We don't reschedule replenish work here -- we will
 271                          * call the restock method and if it still needs
 272                          * more buffers it will schedule replenish */
 273                         return;
 274                 }
 275
 276                 spin_lock_irqsave(&rxq->lock, flags);
 277
 278                 if (list_empty(&rxq->rx_used)) {
 279                         spin_unlock_irqrestore(&rxq->lock, flags);
 280                         __free_pages(page, priv->hw_params.rx_page_order);
 281                         return;
 282                 }
 283                 element = rxq->rx_used.next;
 284                 rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
 285                 list_del(element);
 286
 287                 spin_unlock_irqrestore(&rxq->lock, flags);
 288
 289                 rxb->page = page;
 290                 /* Get physical address of the RB */
 291                 rxb->page_dma = pci_map_page(priv->pci_dev, page, 0,
 292                                 PAGE_SIZE << priv->hw_params.rx_page_order,
 293                                 PCI_DMA_FROMDEVICE);
 294                 /* dma address must be no more than 36 bits */
 295                 BUG_ON(rxb->page_dma & ~DMA_BIT_MASK(36));
 296                 /* and also 256 byte aligned! */
 297                 BUG_ON(rxb->page_dma & DMA_BIT_MASK(8));
 298
 299                 spin_lock_irqsave(&rxq->lock, flags);
 300
 301                 list_add_tail(&rxb->list, &rxq->rx_free);
 302                 rxq->free_count++;
 303                 priv->alloc_rxb_page++;
 304
 305                 spin_unlock_irqrestore(&rxq->lock, flags);
 306         }
 307 }
 308
 309 void iwl_rx_replenish(struct iwl_priv *priv)
 310 {
 311         unsigned long flags;
 312
 313         iwl_rx_allocate(priv, GFP_KERNEL);
 314
 315         spin_lock_irqsave(&priv->lock, flags);
 316         iwl_rx_queue_restock(priv);
 317         spin_unlock_irqrestore(&priv->lock, flags);
 318 }
 319 EXPORT_SYMBOL(iwl_rx_replenish);
 320
 321 void iwl_rx_replenish_now(struct iwl_priv *priv)
 322 {
 323         iwl_rx_allocate(priv, GFP_ATOMIC);
 324
 325         iwl_rx_queue_restock(priv);
 326 }
 327 EXPORT_SYMBOL(iwl_rx_replenish_now);
 328
 329
 330 /* Assumes that the skb field of the buffers in 'pool' is kept accurate.
 331  * If an SKB has been detached, the POOL needs to have its SKB set to NULL
 332  * This free routine walks the list of POOL entries and if SKB is set to
 333  * non NULL it is unmapped and freed
 334  */
 335 void iwl_rx_queue_free(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
 336 {
 337         int i;
 338         for (i = 0; i < RX_QUEUE_SIZE + RX_FREE_BUFFERS; i++) {
 339                 if (rxq->pool[i].page != NULL) {
 340                         pci_unmap_page(priv->pci_dev, rxq->pool[i].page_dma,
 341                                 PAGE_SIZE << priv->hw_params.rx_page_order,
 342                                 PCI_DMA_FROMDEVICE);
 343                         __iwl_free_pages(priv, rxq->pool[i].page);
 344                         rxq->pool[i].page = NULL;
 345                 }
 346         }
 347
 348         pci_free_consistent(priv->pci_dev, 4 * RX_QUEUE_SIZE, rxq->bd,
 349                             rxq->dma_addr);
 350         pci_free_consistent(priv->pci_dev, sizeof(struct iwl_rb_status),
 351                             rxq->rb_stts, rxq->rb_stts_dma);
 352         rxq->bd = NULL;
 353         rxq->rb_stts  = NULL;
 354 }
 355 EXPORT_SYMBOL(iwl_rx_queue_free);
 356
 357 int iwl_rx_queue_alloc(struct iwl_priv *priv)
 358 {
 359         struct iwl_rx_queue *rxq = &priv->rxq;
 360         struct pci_dev *dev = priv->pci_dev;
 361         int i;
 362
 363         spin_lock_init(&rxq->lock);
 364         INIT_LIST_HEAD(&rxq->rx_free);
 365         INIT_LIST_HEAD(&rxq->rx_used);
 366
 367         /* Alloc the circular buffer of Read Buffer Descriptors (RBDs) */
 368         rxq->bd = pci_alloc_consistent(dev, 4 * RX_QUEUE_SIZE, &rxq->dma_addr);
 369         if (!rxq->bd)
 370                 goto err_bd;
 371
 372         rxq->rb_stts = pci_alloc_consistent(dev, sizeof(struct iwl_rb_status),
 373                                         &rxq->rb_stts_dma);
 374         if (!rxq->rb_stts)
 375                 goto err_rb;
 376
 377         /* Fill the rx_used queue with _all_ of the Rx buffers */
 378         for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++)
 379                 list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
 380
 381         /* Set us so that we have processed and used all buffers, but have
 382          * not restocked the Rx queue with fresh buffers */
 383         rxq->read = rxq->write = 0;
 384         rxq->write_actual = 0;
 385         rxq->free_count = 0;
 386         rxq->need_update = 0;
 387         return 0;
 388
 389 err_rb:
 390         pci_free_consistent(priv->pci_dev, 4 * RX_QUEUE_SIZE, rxq->bd,
 391                             rxq->dma_addr);
 392 err_bd:
 393         return -ENOMEM;
 394 }
 395 EXPORT_SYMBOL(iwl_rx_queue_alloc);
 396
 397 void iwl_rx_queue_reset(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
 398 {
 399         unsigned long flags;
 400         int i;
 401         spin_lock_irqsave(&rxq->lock, flags);
 402         INIT_LIST_HEAD(&rxq->rx_free);
 403         INIT_LIST_HEAD(&rxq->rx_used);
 404         /* Fill the rx_used queue with _all_ of the Rx buffers */
 405         for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++) {
 406                 /* In the reset function, these buffers may have been allocated
 407                  * to an SKB, so we need to unmap and free potential storage */
 408                 if (rxq->pool[i].page != NULL) {
 409                         pci_unmap_page(priv->pci_dev, rxq->pool[i].page_dma,
 410                                 PAGE_SIZE << priv->hw_params.rx_page_order,
 411                                 PCI_DMA_FROMDEVICE);
 412                         __iwl_free_pages(priv, rxq->pool[i].page);
 413                         rxq->pool[i].page = NULL;
 414                 }
 415                 list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
 416         }
 417
 418         /* Set us so that we have processed and used all buffers, but have
 419          * not restocked the Rx queue with fresh buffers */
 420         rxq->read = rxq->write = 0;
 421         rxq->write_actual = 0;
 422         rxq->free_count = 0;
 423         spin_unlock_irqrestore(&rxq->lock, flags);
 424 }
 425
 426 int iwl_rx_init(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
 427 {
 428         u32 rb_size;
 429         const u32 rfdnlog = RX_QUEUE_SIZE_LOG; /* 256 RBDs */
 430         u32 rb_timeout = 0; /* FIXME: RX_RB_TIMEOUT for all devices? */
 431
 432         if (!priv->cfg->use_isr_legacy)
 433                 rb_timeout = RX_RB_TIMEOUT;
 434
 435         if (priv->cfg->mod_params->amsdu_size_8K)
 436                 rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_8K;
 437         else
 438                 rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K;
 439
 440         /* Stop Rx DMA */
 441         iwl_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
 442
 443         /* Reset driver's Rx queue write index */
 444         iwl_write_direct32(priv, FH_RSCSR_CHNL0_RBDCB_WPTR_REG, 0);
 445
 446         /* Tell device where to find RBD circular buffer in DRAM */
 447         iwl_write_direct32(priv, FH_RSCSR_CHNL0_RBDCB_BASE_REG,
 448                            (u32)(rxq->dma_addr >> 8));
 449
 450         /* Tell device where in DRAM to update its Rx status */
 451         iwl_write_direct32(priv, FH_RSCSR_CHNL0_STTS_WPTR_REG,
 452                            rxq->rb_stts_dma >> 4);
 453
 454         /* Enable Rx DMA
 455          * FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY is set because of HW bug in
 456          *      the credit mechanism in 5000 HW RX FIFO
 457          * Direct rx interrupts to hosts
 458          * Rx buffer size 4 or 8k
 459          * RB timeout 0x10
 460          * 256 RBDs
 461          */
 462         iwl_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG,
 463                            FH_RCSR_RX_CONFIG_CHNL_EN_ENABLE_VAL |
 464                            FH_RCSR_CHNL0_RX_IGNORE_RXF_EMPTY |
 465                            FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_INT_HOST_VAL |
 466                            FH_RCSR_CHNL0_RX_CONFIG_SINGLE_FRAME_MSK |
 467                            rb_size|
 468                            (rb_timeout << FH_RCSR_RX_CONFIG_REG_IRQ_RBTH_POS)|
 469                            (rfdnlog << FH_RCSR_RX_CONFIG_RBDCB_SIZE_POS));
 470
 471         /* Set interrupt coalescing timer to default (2048 usecs) */
 472         iwl_write8(priv, CSR_INT_COALESCING, IWL_HOST_INT_TIMEOUT_DEF);
 473
 474         return 0;
 475 }
 476
 477 int iwl_rxq_stop(struct iwl_priv *priv)
 478 {
 479
 480         /* stop Rx DMA */
 481         iwl_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
 482         iwl_poll_direct_bit(priv, FH_MEM_RSSR_RX_STATUS_REG,
 483                             FH_RSSR_CHNL0_RX_STATUS_CHNL_IDLE, 1000);
 484
 485         return 0;
 486 }
 487 EXPORT_SYMBOL(iwl_rxq_stop);
 488
 489 void iwl_rx_missed_beacon_notif(struct iwl_priv *priv,
 490                                 struct iwl_rx_mem_buffer *rxb)
 491
 492 {
 493         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 494         struct iwl_missed_beacon_notif *missed_beacon;
 495
 496         missed_beacon = &pkt->u.missed_beacon;
 497         if (le32_to_cpu(missed_beacon->consecutive_missed_beacons) >
 498             priv->missed_beacon_threshold) {
 499                 IWL_DEBUG_CALIB(priv, "missed bcn cnsq %d totl %d rcd %d expctd %d\n",
 500                     le32_to_cpu(missed_beacon->consecutive_missed_beacons),
 501                     le32_to_cpu(missed_beacon->total_missed_becons),
 502                     le32_to_cpu(missed_beacon->num_recvd_beacons),
 503                     le32_to_cpu(missed_beacon->num_expected_beacons));
 504                 if (!test_bit(STATUS_SCANNING, &priv->status))
 505                         iwl_init_sensitivity(priv);
 506         }
 507 }
 508 EXPORT_SYMBOL(iwl_rx_missed_beacon_notif);
 509
 510 void iwl_rx_spectrum_measure_notif(struct iwl_priv *priv,
 511                                           struct iwl_rx_mem_buffer *rxb)
 512 {
 513         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 514         struct iwl_spectrum_notification *report = &(pkt->u.spectrum_notif);
 515
 516         if (!report->state) {
 517                 IWL_DEBUG_11H(priv,
 518                         "Spectrum Measure Notification: Start\n");
 519                 return;
 520         }
 521
 522         memcpy(&priv->measure_report, report, sizeof(*report));
 523         priv->measurement_status |= MEASUREMENT_READY;
 524 }
 525 EXPORT_SYMBOL(iwl_rx_spectrum_measure_notif);
 526
 527
 528
 529 /* Calculate noise level, based on measurements during network silence just
 530  *   before arriving beacon.  This measurement can be done only if we know
 531  *   exactly when to expect beacons, therefore only when we're associated. */
 532 static void iwl_rx_calc_noise(struct iwl_priv *priv)
 533 {
 534         struct statistics_rx_non_phy *rx_info
 535                                 = &(priv->statistics.rx.general);
 536         int num_active_rx = 0;
 537         int total_silence = 0;
 538         int bcn_silence_a =
 539                 le32_to_cpu(rx_info->beacon_silence_rssi_a) & IN_BAND_FILTER;
 540         int bcn_silence_b =
 541                 le32_to_cpu(rx_info->beacon_silence_rssi_b) & IN_BAND_FILTER;
 542         int bcn_silence_c =
 543                 le32_to_cpu(rx_info->beacon_silence_rssi_c) & IN_BAND_FILTER;
 544
 545         if (bcn_silence_a) {
 546                 total_silence += bcn_silence_a;
 547                 num_active_rx++;
 548         }
 549         if (bcn_silence_b) {
 550                 total_silence += bcn_silence_b;
 551                 num_active_rx++;
 552         }
 553         if (bcn_silence_c) {
 554                 total_silence += bcn_silence_c;
 555                 num_active_rx++;
 556         }
 557
 558         /* Average among active antennas */
 559         if (num_active_rx)
 560                 priv->last_rx_noise = (total_silence / num_active_rx) - 107;
 561         else
 562                 priv->last_rx_noise = IWL_NOISE_MEAS_NOT_AVAILABLE;
 563
 564         IWL_DEBUG_CALIB(priv, "inband silence a %u, b %u, c %u, dBm %d\n",
 565                         bcn_silence_a, bcn_silence_b, bcn_silence_c,
 566                         priv->last_rx_noise);
 567 }
 568
 569 #ifdef CONFIG_IWLWIFI_DEBUG
 570 /*
 571  *  based on the assumption of all statistics counter are in DWORD
 572  *  FIXME: This function is for debugging, do not deal with
 573  *  the case of counters roll-over.
 574  */
 575 static void iwl_accumulative_statistics(struct iwl_priv *priv,
 576                                         __le32 *stats)
 577 {
 578         int i;
 579         __le32 *prev_stats;
 580         u32 *accum_stats;
 581         u32 *delta, *max_delta;
 582
 583         prev_stats = (__le32 *)&priv->statistics;
 584         accum_stats = (u32 *)&priv->accum_statistics;
 585         delta = (u32 *)&priv->delta_statistics;
 586         max_delta = (u32 *)&priv->max_delta;
 587
 588         for (i = sizeof(__le32); i < sizeof(struct iwl_notif_statistics);
 589              i += sizeof(__le32), stats++, prev_stats++, delta++,
 590              max_delta++, accum_stats++) {
 591                 if (le32_to_cpu(*stats) > le32_to_cpu(*prev_stats)) {
 592                         *delta = (le32_to_cpu(*stats) -
 593                                 le32_to_cpu(*prev_stats));
 594                         *accum_stats += *delta;
 595                         if (*delta > *max_delta)
 596                                 *max_delta = *delta;
 597                 }
 598         }
 599
 600         /* reset accumulative statistics for "no-counter" type statistics */
 601         priv->accum_statistics.general.temperature =
 602                 priv->statistics.general.temperature;
 603         priv->accum_statistics.general.temperature_m =
 604                 priv->statistics.general.temperature_m;
 605         priv->accum_statistics.general.ttl_timestamp =
 606                 priv->statistics.general.ttl_timestamp;
 607         priv->accum_statistics.tx.tx_power.ant_a =
 608                 priv->statistics.tx.tx_power.ant_a;
 609         priv->accum_statistics.tx.tx_power.ant_b =
 610                 priv->statistics.tx.tx_power.ant_b;
 611         priv->accum_statistics.tx.tx_power.ant_c =
 612                 priv->statistics.tx.tx_power.ant_c;
 613 }
 614 #endif
 615
 616 #define REG_RECALIB_PERIOD (60)
 617
 618 #define PLCP_MSG "plcp_err exceeded %u, %u, %u, %u, %u, %d, %u mSecs\n"
 619 void iwl_rx_statistics(struct iwl_priv *priv,
 620                               struct iwl_rx_mem_buffer *rxb)
 621 {
 622         int change;
 623         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 624         int combined_plcp_delta;
 625         unsigned int plcp_msec;
 626         unsigned long plcp_received_jiffies;
 627
 628         IWL_DEBUG_RX(priv, "Statistics notification received (%d vs %d).\n",
 629                      (int)sizeof(priv->statistics),
 630                      le32_to_cpu(pkt->len_n_flags) & FH_RSCSR_FRAME_SIZE_MSK);
 631
 632         change = ((priv->statistics.general.temperature !=
 633                    pkt->u.stats.general.temperature) ||
 634                   ((priv->statistics.flag &
 635                     STATISTICS_REPLY_FLG_HT40_MODE_MSK) !=
 636                    (pkt->u.stats.flag & STATISTICS_REPLY_FLG_HT40_MODE_MSK)));
 637
 638 #ifdef CONFIG_IWLWIFI_DEBUG
 639         iwl_accumulative_statistics(priv, (__le32 *)&pkt->u.stats);
 640 #endif
 641         /*
 642          * check for plcp_err and trigger radio reset if it exceeds
 643          * the plcp error threshold plcp_delta.
 644          */
 645         plcp_received_jiffies = jiffies;
 646         plcp_msec = jiffies_to_msecs((long) plcp_received_jiffies -
 647                                         (long) priv->plcp_jiffies);
 648         priv->plcp_jiffies = plcp_received_jiffies;
 649         /*
 650          * check to make sure plcp_msec is not 0 to prevent division
 651          * by zero.
 652          */
 653         if (plcp_msec) {
 654                 combined_plcp_delta =
 655                         (le32_to_cpu(pkt->u.stats.rx.ofdm.plcp_err) -
 656                         le32_to_cpu(priv->statistics.rx.ofdm.plcp_err)) +
 657                         (le32_to_cpu(pkt->u.stats.rx.ofdm_ht.plcp_err) -
 658                         le32_to_cpu(priv->statistics.rx.ofdm_ht.plcp_err));
 659
 660                 if ((combined_plcp_delta > 0) &&
 661                         ((combined_plcp_delta * 100) / plcp_msec) >
 662                         priv->cfg->plcp_delta_threshold) {
 663                         /*
 664                          * if plcp_err exceed the threshold, the following
 665                          * data is printed in csv format:
 666                          *    Text: plcp_err exceeded %d,
 667                          *    Received ofdm.plcp_err,
 668                          *    Current ofdm.plcp_err,
 669                          *    Received ofdm_ht.plcp_err,
 670                          *    Current ofdm_ht.plcp_err,
 671                          *    combined_plcp_delta,
 672                          *    plcp_msec
 673                          */
 674                         IWL_DEBUG_RADIO(priv, PLCP_MSG,
 675                                 priv->cfg->plcp_delta_threshold,
 676                                 le32_to_cpu(pkt->u.stats.rx.ofdm.plcp_err),
 677                                 le32_to_cpu(priv->statistics.rx.ofdm.plcp_err),
 678                                 le32_to_cpu(pkt->u.stats.rx.ofdm_ht.plcp_err),
 679                                 le32_to_cpu(
 680                                         priv->statistics.rx.ofdm_ht.plcp_err),
 681                                 combined_plcp_delta, plcp_msec);
 682
 683                         /*
 684                          * Reset the RF radio due to the high plcp
 685                          * error rate
 686                          */
 687                         iwl_force_reset(priv, IWL_RF_RESET);
 688                 }
 689         }
 690
 691         memcpy(&priv->statistics, &pkt->u.stats, sizeof(priv->statistics));
 692
 693         set_bit(STATUS_STATISTICS, &priv->status);
 694
 695         /* Reschedule the statistics timer to occur in
 696          * REG_RECALIB_PERIOD seconds to ensure we get a
 697          * thermal update even if the uCode doesn't give
 698          * us one */
 699         mod_timer(&priv->statistics_periodic, jiffies +
 700                   msecs_to_jiffies(REG_RECALIB_PERIOD * 1000));
 701
 702         if (unlikely(!test_bit(STATUS_SCANNING, &priv->status)) &&
 703             (pkt->hdr.cmd == STATISTICS_NOTIFICATION)) {
 704                 iwl_rx_calc_noise(priv);
 705                 queue_work(priv->workqueue, &priv->run_time_calib_work);
 706         }
 707         if (priv->cfg->ops->lib->temp_ops.temperature && change)
 708                 priv->cfg->ops->lib->temp_ops.temperature(priv);
 709 }
 710 EXPORT_SYMBOL(iwl_rx_statistics);
 711
 712 void iwl_reply_statistics(struct iwl_priv *priv,
 713                               struct iwl_rx_mem_buffer *rxb)
 714 {
 715         struct iwl_rx_packet *pkt = rxb_addr(rxb);
 716
 717         if (le32_to_cpu(pkt->u.stats.flag) & UCODE_STATISTICS_CLEAR_MSK) {
 718 #ifdef CONFIG_IWLWIFI_DEBUG
 719                 memset(&priv->accum_statistics, 0,
 720                         sizeof(struct iwl_notif_statistics));
 721                 memset(&priv->delta_statistics, 0,
 722                         sizeof(struct iwl_notif_statistics));
 723                 memset(&priv->max_delta, 0,
 724                         sizeof(struct iwl_notif_statistics));
 725 #endif
 726                 IWL_DEBUG_RX(priv, "Statistics have been cleared\n");
 727         }
 728         iwl_rx_statistics(priv, rxb);
 729 }
 730 EXPORT_SYMBOL(iwl_reply_statistics);
 731
 732 /* Calc max signal level (dBm) among 3 possible receivers */
 733 static inline int iwl_calc_rssi(struct iwl_priv *priv,
 734                                 struct iwl_rx_phy_res *rx_resp)
 735 {
 736         return priv->cfg->ops->utils->calc_rssi(priv, rx_resp);
 737 }
 738
 739 #ifdef CONFIG_IWLWIFI_DEBUG
 740 /**
 741  * iwl_dbg_report_frame - dump frame to syslog during debug sessions
 742  *
 743  * You may hack this function to show different aspects of received frames,
 744  * including selective frame dumps.
 745  * group100 parameter selects whether to show 1 out of 100 good data frames.
 746  *    All beacon and probe response frames are printed.
 747  */
 748 static void iwl_dbg_report_frame(struct iwl_priv *priv,
 749                       struct iwl_rx_phy_res *phy_res, u16 length,
 750                       struct ieee80211_hdr *header, int group100)
 751 {
 752         u32 to_us;
 753         u32 print_summary = 0;
 754         u32 print_dump = 0;     /* set to 1 to dump all frames' contents */
 755         u32 hundred = 0;
 756         u32 dataframe = 0;
 757         __le16 fc;
 758         u16 seq_ctl;
 759         u16 channel;
 760         u16 phy_flags;
 761         u32 rate_n_flags;
 762         u32 tsf_low;
 763         int rssi;
 764
 765         if (likely(!(iwl_get_debug_level(priv) & IWL_DL_RX)))
 766                 return;
 767
 768         /* MAC header */
 769         fc = header->frame_control;
 770         seq_ctl = le16_to_cpu(header->seq_ctrl);
 771
 772         /* metadata */
 773         channel = le16_to_cpu(phy_res->channel);
 774         phy_flags = le16_to_cpu(phy_res->phy_flags);
 775         rate_n_flags = le32_to_cpu(phy_res->rate_n_flags);
 776
 777         /* signal statistics */
 778         rssi = iwl_calc_rssi(priv, phy_res);
 779         tsf_low = le64_to_cpu(phy_res->timestamp) & 0x0ffffffff;
 780
 781         to_us = !compare_ether_addr(header->addr1, priv->mac_addr);
 782
 783         /* if data frame is to us and all is good,
 784          *   (optionally) print summary for only 1 out of every 100 */
 785         if (to_us && (fc & ~cpu_to_le16(IEEE80211_FCTL_PROTECTED)) ==
 786             cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FTYPE_DATA)) {
 787                 dataframe = 1;
 788                 if (!group100)
 789                         print_summary = 1;      /* print each frame */
 790                 else if (priv->framecnt_to_us < 100) {
 791                         priv->framecnt_to_us++;
 792                         print_summary = 0;
 793                 } else {
 794                         priv->framecnt_to_us = 0;
 795                         print_summary = 1;
 796                         hundred = 1;
 797                 }
 798         } else {
 799                 /* print summary for all other frames */
 800                 print_summary = 1;
 801         }
 802
 803         if (print_summary) {
 804                 char *title;
 805                 int rate_idx;
 806                 u32 bitrate;
 807
 808                 if (hundred)
 809                         title = "100Frames";
 810                 else if (ieee80211_has_retry(fc))
 811                         title = "Retry";
 812                 else if (ieee80211_is_assoc_resp(fc))
 813                         title = "AscRsp";
 814                 else if (ieee80211_is_reassoc_resp(fc))
 815                         title = "RasRsp";
 816                 else if (ieee80211_is_probe_resp(fc)) {
 817                         title = "PrbRsp";
 818                         print_dump = 1; /* dump frame contents */
 819                 } else if (ieee80211_is_beacon(fc)) {
 820                         title = "Beacon";
 821                         print_dump = 1; /* dump frame contents */
 822                 } else if (ieee80211_is_atim(fc))
 823                         title = "ATIM";
 824                 else if (ieee80211_is_auth(fc))
 825                         title = "Auth";
 826                 else if (ieee80211_is_deauth(fc))
 827                         title = "DeAuth";
 828                 else if (ieee80211_is_disassoc(fc))
 829                         title = "DisAssoc";
 830                 else
 831                         title = "Frame";
 832
 833                 rate_idx = iwl_hwrate_to_plcp_idx(rate_n_flags);
 834                 if (unlikely((rate_idx < 0) || (rate_idx >= IWL_RATE_COUNT))) {
 835                         bitrate = 0;
 836                         WARN_ON_ONCE(1);
 837                 } else {
 838                         bitrate = iwl_rates[rate_idx].ieee / 2;
 839                 }
 840
 841                 /* print frame summary.
 842                  * MAC addresses show just the last byte (for brevity),
 843                  *    but you can hack it to show more, if you'd like to. */
 844                 if (dataframe)
 845                         IWL_DEBUG_RX(priv, "%s: mhd=0x%04x, dst=0x%02x, "
 846                                      "len=%u, rssi=%d, chnl=%d, rate=%u, \n",
 847                                      title, le16_to_cpu(fc), header->addr1[5],
 848                                      length, rssi, channel, bitrate);
 849                 else {
 850                         /* src/dst addresses assume managed mode */
 851                         IWL_DEBUG_RX(priv, "%s: 0x%04x, dst=0x%02x, src=0x%02x, "
 852                                      "len=%u, rssi=%d, tim=%lu usec, "
 853                                      "phy=0x%02x, chnl=%d\n",
 854                                      title, le16_to_cpu(fc), header->addr1[5],
 855                                      header->addr3[5], length, rssi,
 856                                      tsf_low - priv->scan_start_tsf,
 857                                      phy_flags, channel);
 858                 }
 859         }
 860         if (print_dump)
 861                 iwl_print_hex_dump(priv, IWL_DL_RX, header, length);
 862 }
 863 #endif
 864
 865 /*
 866  * returns non-zero if packet should be dropped
 867  */
 868 int iwl_set_decrypted_flag(struct iwl_priv *priv,
 869                            struct ieee80211_hdr *hdr,
 870                            u32 decrypt_res,
 871                            struct ieee80211_rx_status *stats)
 872 {
 873         u16 fc = le16_to_cpu(hdr->frame_control);
 874
 875         if (priv->active_rxon.filter_flags & RXON_FILTER_DIS_DECRYPT_MSK)
 876                 return 0;
 877
 878         if (!(fc & IEEE80211_FCTL_PROTECTED))
 879                 return 0;
 880
 881         IWL_DEBUG_RX(priv, "decrypt_res:0x%x\n", decrypt_res);
 882         switch (decrypt_res & RX_RES_STATUS_SEC_TYPE_MSK) {
 883         case RX_RES_STATUS_SEC_TYPE_TKIP:
 884                 /* The uCode has got a bad phase 1 Key, pushes the packet.
 885                  * Decryption will be done in SW. */
 886                 if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
 887                     RX_RES_STATUS_BAD_KEY_TTAK)
 888                         break;
 889
 890         case RX_RES_STATUS_SEC_TYPE_WEP:
 891                 if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
 892                     RX_RES_STATUS_BAD_ICV_MIC) {
 893                         /* bad ICV, the packet is destroyed since the
 894                          * decryption is inplace, drop it */
 895                         IWL_DEBUG_RX(priv, "Packet destroyed\n");
 896                         return -1;
 897                 }
 898         case RX_RES_STATUS_SEC_TYPE_CCMP:
 899                 if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
 900                     RX_RES_STATUS_DECRYPT_OK) {
 901                         IWL_DEBUG_RX(priv, "hw decrypt successfully!!!\n");
 902                         stats->flag |= RX_FLAG_DECRYPTED;
 903                 }
 904                 break;
 905
 906         default:
 907                 break;
 908         }
 909         return 0;
 910 }
 911 EXPORT_SYMBOL(iwl_set_decrypted_flag);
 912
 913 static u32 iwl_translate_rx_status(struct iwl_priv *priv, u32 decrypt_in)
 914 {
 915         u32 decrypt_out = 0;
 916
 917         if ((decrypt_in & RX_RES_STATUS_STATION_FOUND) ==
 918                                         RX_RES_STATUS_STATION_FOUND)
 919                 decrypt_out |= (RX_RES_STATUS_STATION_FOUND |
 920                                 RX_RES_STATUS_NO_STATION_INFO_MISMATCH);
 921
 922         decrypt_out |= (decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK);
 923
 924         /* packet was not encrypted */
 925         if ((decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) ==
 926                                         RX_RES_STATUS_SEC_TYPE_NONE)
 927                 return decrypt_out;
 928
 929         /* packet was encrypted with unknown alg */
 930         if ((decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) ==
 931                                         RX_RES_STATUS_SEC_TYPE_ERR)
 932                 return decrypt_out;
 933
 934         /* decryption was not done in HW */
 935         if ((decrypt_in & RX_MPDU_RES_STATUS_DEC_DONE_MSK) !=
 936                                         RX_MPDU_RES_STATUS_DEC_DONE_MSK)
 937                 return decrypt_out;
 938
 939         switch (decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) {
 940
 941         case RX_RES_STATUS_SEC_TYPE_CCMP:
 942                 /* alg is CCM: check MIC only */
 943                 if (!(decrypt_in & RX_MPDU_RES_STATUS_MIC_OK))
 944                         /* Bad MIC */
 945                         decrypt_out |= RX_RES_STATUS_BAD_ICV_MIC;
 946                 else
 947                         decrypt_out |= RX_RES_STATUS_DECRYPT_OK;
 948
 949                 break;
 950
 951         case RX_RES_STATUS_SEC_TYPE_TKIP:
 952                 if (!(decrypt_in & RX_MPDU_RES_STATUS_TTAK_OK)) {
 953                         /* Bad TTAK */
 954                         decrypt_out |= RX_RES_STATUS_BAD_KEY_TTAK;
 955                         break;
 956                 }
 957                 /* fall through if TTAK OK */
 958         default:
 959                 if (!(decrypt_in & RX_MPDU_RES_STATUS_ICV_OK))
 960                         decrypt_out |= RX_RES_STATUS_BAD_ICV_MIC;
 961                 else
 962                         decrypt_out |= RX_RES_STATUS_DECRYPT_OK;
 963                 break;
 964         };
 965
 966         IWL_DEBUG_RX(priv, "decrypt_in:0x%x  decrypt_out = 0x%x\n",
 967                                         decrypt_in, decrypt_out);
 968
 969         return decrypt_out;
 970 }
 971
 972 static void iwl_pass_packet_to_mac80211(struct iwl_priv *priv,
 973                                         struct ieee80211_hdr *hdr,
 974                                         u16 len,
 975                                         u32 ampdu_status,
 976                                         struct iwl_rx_mem_buffer *rxb,
 977                                         struct ieee80211_rx_status *stats)
 978 {
 979         struct sk_buff *skb;
 980         int ret = 0;
 981         __le16 fc = hdr->frame_control;
 982
 983         /* We only process data packets if the interface is open */
 984         if (unlikely(!priv->is_open)) {
 985                 IWL_DEBUG_DROP_LIMIT(priv,
 986                     "Dropping packet while interface is not open.\n");
 987                 return;
 988         }
 989
 990         /* In case of HW accelerated crypto and bad decryption, drop */
 991         if (!priv->cfg->mod_params->sw_crypto &&
 992             iwl_set_decrypted_flag(priv, hdr, ampdu_status, stats))
 993                 return;
 994
 995         skb = alloc_skb(IWL_LINK_HDR_MAX * 2, GFP_ATOMIC);
 996         if (!skb) {
 997                 IWL_ERR(priv, "alloc_skb failed\n");
 998                 return;
 999         }
1000
1001         skb_reserve(skb, IWL_LINK_HDR_MAX);
1002         skb_add_rx_frag(skb, 0, rxb->page, (void *)hdr - rxb_addr(rxb), len);
1003
1004         /* mac80211 currently doesn't support paged SKB. Convert it to
1005          * linear SKB for management frame and data frame requires
1006          * software decryption or software defragementation. */
1007         if (ieee80211_is_mgmt(fc) ||
1008             ieee80211_has_protected(fc) ||
1009             ieee80211_has_morefrags(fc) ||
1010             le16_to_cpu(hdr->seq_ctrl) & IEEE80211_SCTL_FRAG)
1011                 ret = skb_linearize(skb);
1012         else
1013                 ret = __pskb_pull_tail(skb, min_t(u16, IWL_LINK_HDR_MAX, len)) ?
1014                          0 : -ENOMEM;
1015
1016         if (ret) {
1017                 kfree_skb(skb);
1018                 goto out;
1019         }
1020
1021         /*
1022          * XXX: We cannot touch the page and its virtual memory (hdr) after
1023          * here. It might have already been freed by the above skb change.
1024          */
1025
1026         iwl_update_stats(priv, false, fc, len);
1027         memcpy(IEEE80211_SKB_RXCB(skb), stats, sizeof(*stats));
1028
1029         ieee80211_rx(priv->hw, skb);
1030  out:
1031         priv->alloc_rxb_page--;
1032         rxb->page = NULL;
1033 }
1034
1035 /* This is necessary only for a number of statistics, see the caller. */
1036 static int iwl_is_network_packet(struct iwl_priv *priv,
1037                 struct ieee80211_hdr *header)
1038 {
1039         /* Filter incoming packets to determine if they are targeted toward
1040          * this network, discarding packets coming from ourselves */
1041         switch (priv->iw_mode) {
1042         case NL80211_IFTYPE_ADHOC: /* Header: Dest. | Source    | BSSID */
1043                 /* packets to our IBSS update information */
1044                 return !compare_ether_addr(header->addr3, priv->bssid);
1045         case NL80211_IFTYPE_STATION: /* Header: Dest. | AP{BSSID} | Source */
1046                 /* packets to our IBSS update information */
1047                 return !compare_ether_addr(header->addr2, priv->bssid);
1048         default:
1049                 return 1;
1050         }
1051 }
1052
1053 /* Called for REPLY_RX (legacy ABG frames), or
1054  * REPLY_RX_MPDU_CMD (HT high-throughput N frames). */
1055 void iwl_rx_reply_rx(struct iwl_priv *priv,
1056                                 struct iwl_rx_mem_buffer *rxb)
1057 {
1058         struct ieee80211_hdr *header;
1059         struct ieee80211_rx_status rx_status;
1060         struct iwl_rx_packet *pkt = rxb_addr(rxb);
1061         struct iwl_rx_phy_res *phy_res;
1062         __le32 rx_pkt_status;
1063         struct iwl4965_rx_mpdu_res_start *amsdu;
1064         u32 len;
1065         u32 ampdu_status;
1066         u32 rate_n_flags;
1067
1068         /**
1069          * REPLY_RX and REPLY_RX_MPDU_CMD are handled differently.
1070          *      REPLY_RX: physical layer info is in this buffer
1071          *      REPLY_RX_MPDU_CMD: physical layer info was sent in separate
1072          *              command and cached in priv->last_phy_res
1073          *
1074          * Here we set up local variables depending on which command is
1075          * received.
1076          */
1077         if (pkt->hdr.cmd == REPLY_RX) {
1078                 phy_res = (struct iwl_rx_phy_res *)pkt->u.raw;
1079                 header = (struct ieee80211_hdr *)(pkt->u.raw + sizeof(*phy_res)
1080                                 + phy_res->cfg_phy_cnt);
1081
1082                 len = le16_to_cpu(phy_res->byte_count);
1083                 rx_pkt_status = *(__le32 *)(pkt->u.raw + sizeof(*phy_res) +
1084                                 phy_res->cfg_phy_cnt + len);
1085                 ampdu_status = le32_to_cpu(rx_pkt_status);
1086         } else {
1087                 if (!priv->last_phy_res[0]) {
1088                         IWL_ERR(priv, "MPDU frame without cached PHY data\n");
1089                         return;
1090                 }
1091                 phy_res = (struct iwl_rx_phy_res *)&priv->last_phy_res[1];
1092                 amsdu = (struct iwl4965_rx_mpdu_res_start *)pkt->u.raw;
1093                 header = (struct ieee80211_hdr *)(pkt->u.raw + sizeof(*amsdu));
1094                 len = le16_to_cpu(amsdu->byte_count);
1095                 rx_pkt_status = *(__le32 *)(pkt->u.raw + sizeof(*amsdu) + len);
1096                 ampdu_status = iwl_translate_rx_status(priv,
1097                                 le32_to_cpu(rx_pkt_status));
1098         }
1099
1100         if ((unlikely(phy_res->cfg_phy_cnt > 20))) {
1101                 IWL_DEBUG_DROP(priv, "dsp size out of range [0,20]: %d/n",
1102                                 phy_res->cfg_phy_cnt);
1103                 return;
1104         }
1105
1106         if (!(rx_pkt_status & RX_RES_STATUS_NO_CRC32_ERROR) ||
1107             !(rx_pkt_status & RX_RES_STATUS_NO_RXE_OVERFLOW)) {
1108                 IWL_DEBUG_RX(priv, "Bad CRC or FIFO: 0x%08X.\n",
1109                                 le32_to_cpu(rx_pkt_status));
1110                 return;
1111         }
1112
1113         /* This will be used in several places later */
1114         rate_n_flags = le32_to_cpu(phy_res->rate_n_flags);
1115
1116         /* rx_status carries information about the packet to mac80211 */
1117         rx_status.mactime = le64_to_cpu(phy_res->timestamp);
1118         rx_status.freq =
1119                 ieee80211_channel_to_frequency(le16_to_cpu(phy_res->channel));
1120         rx_status.band = (phy_res->phy_flags & RX_RES_PHY_FLAGS_BAND_24_MSK) ?
1121                                 IEEE80211_BAND_2GHZ : IEEE80211_BAND_5GHZ;
1122         rx_status.rate_idx =
1123                 iwl_hwrate_to_mac80211_idx(rate_n_flags, rx_status.band);
1124         rx_status.flag = 0;
1125
1126         /* TSF isn't reliable. In order to allow smooth user experience,
1127          * this W/A doesn't propagate it to the mac80211 */
1128         /*rx_status.flag |= RX_FLAG_TSFT;*/
1129
1130         priv->ucode_beacon_time = le32_to_cpu(phy_res->beacon_time_stamp);
1131
1132         /* Find max signal strength (dBm) among 3 antenna/receiver chains */
1133         rx_status.signal = iwl_calc_rssi(priv, phy_res);
1134
1135         /* Meaningful noise values are available only from beacon statistics,
1136          *   which are gathered only when associated, and indicate noise
1137          *   only for the associated network channel ...
1138          * Ignore these noise values while scanning (other channels) */
1139         if (iwl_is_associated(priv) &&
1140             !test_bit(STATUS_SCANNING, &priv->status)) {
1141                 rx_status.noise = priv->last_rx_noise;
1142         } else {
1143                 rx_status.noise = IWL_NOISE_MEAS_NOT_AVAILABLE;
1144         }
1145
1146         /* Reset beacon noise level if not associated. */
1147         if (!iwl_is_associated(priv))
1148                 priv->last_rx_noise = IWL_NOISE_MEAS_NOT_AVAILABLE;
1149
1150 #ifdef CONFIG_IWLWIFI_DEBUG
1151         /* Set "1" to report good data frames in groups of 100 */
1152         if (unlikely(iwl_get_debug_level(priv) & IWL_DL_RX))
1153                 iwl_dbg_report_frame(priv, phy_res, len, header, 1);
1154 #endif
1155         iwl_dbg_log_rx_data_frame(priv, len, header);
1156         IWL_DEBUG_STATS_LIMIT(priv, "Rssi %d, noise %d, TSF %llu\n",
1157                 rx_status.signal, rx_status.noise,
1158                 (unsigned long long)rx_status.mactime);
1159
1160         /*
1161          * "antenna number"
1162          *
1163          * It seems that the antenna field in the phy flags value
1164          * is actually a bit field. This is undefined by radiotap,
1165          * it wants an actual antenna number but I always get "7"
1166          * for most legacy frames I receive indicating that the
1167          * same frame was received on all three RX chains.
1168          *
1169          * I think this field should be removed in favor of a
1170          * new 802.11n radiotap field "RX chains" that is defined
1171          * as a bitmask.
1172          */
1173         rx_status.antenna =
1174                 (le16_to_cpu(phy_res->phy_flags) & RX_RES_PHY_FLAGS_ANTENNA_MSK)
1175                 >> RX_RES_PHY_FLAGS_ANTENNA_POS;
1176
1177         /* set the preamble flag if appropriate */
1178         if (phy_res->phy_flags & RX_RES_PHY_FLAGS_SHORT_PREAMBLE_MSK)
1179                 rx_status.flag |= RX_FLAG_SHORTPRE;
1180
1181         /* Set up the HT phy flags */
1182         if (rate_n_flags & RATE_MCS_HT_MSK)
1183                 rx_status.flag |= RX_FLAG_HT;
1184         if (rate_n_flags & RATE_MCS_HT40_MSK)
1185                 rx_status.flag |= RX_FLAG_40MHZ;
1186         if (rate_n_flags & RATE_MCS_SGI_MSK)
1187                 rx_status.flag |= RX_FLAG_SHORT_GI;
1188
1189         if (iwl_is_network_packet(priv, header)) {
1190                 priv->last_rx_rssi = rx_status.signal;
1191                 priv->last_beacon_time =  priv->ucode_beacon_time;
1192                 priv->last_tsf = le64_to_cpu(phy_res->timestamp);
1193         }
1194
1195         iwl_pass_packet_to_mac80211(priv, header, len, ampdu_status,
1196                                     rxb, &rx_status);
1197 }
1198 EXPORT_SYMBOL(iwl_rx_reply_rx);
1199
1200 /* Cache phy data (Rx signal strength, etc) for HT frame (REPLY_RX_PHY_CMD).
1201  * This will be used later in iwl_rx_reply_rx() for REPLY_RX_MPDU_CMD. */
1202 void iwl_rx_reply_rx_phy(struct iwl_priv *priv,
1203                                     struct iwl_rx_mem_buffer *rxb)
1204 {
1205         struct iwl_rx_packet *pkt = rxb_addr(rxb);
1206         priv->last_phy_res[0] = 1;
1207         memcpy(&priv->last_phy_res[1], &(pkt->u.raw[0]),
1208                sizeof(struct iwl_rx_phy_res));
1209 }
1210 EXPORT_SYMBOL(iwl_rx_reply_rx_phy);