Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tiwai/sound-2.6
[linux-2.6] / 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 <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 int iwl_rx_queue_update_write_ptr(struct iwl_priv *priv, struct iwl_rx_queue *q)
127 {
128         u32 reg = 0;
129         int ret = 0;
130         unsigned long flags;
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_set_bit(priv, CSR_GP_CNTRL,
143                                     CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
144                         goto exit_unlock;
145                 }
146
147                 ret = iwl_grab_nic_access(priv);
148                 if (ret)
149                         goto exit_unlock;
150
151                 /* Device expects a multiple of 8 */
152                 iwl_write_direct32(priv, FH_RSCSR_CHNL0_WPTR,
153                                      q->write & ~0x7);
154                 iwl_release_nic_access(priv);
155
156         /* Else device is assumed to be awake */
157         } else
158                 /* Device expects a multiple of 8 */
159                 iwl_write32(priv, FH_RSCSR_CHNL0_WPTR, q->write & ~0x7);
160
161
162         q->need_update = 0;
163
164  exit_unlock:
165         spin_unlock_irqrestore(&q->lock, flags);
166         return ret;
167 }
168 EXPORT_SYMBOL(iwl_rx_queue_update_write_ptr);
169 /**
170  * iwl_dma_addr2rbd_ptr - convert a DMA address to a uCode read buffer ptr
171  */
172 static inline __le32 iwl_dma_addr2rbd_ptr(struct iwl_priv *priv,
173                                           dma_addr_t dma_addr)
174 {
175         return cpu_to_le32((u32)(dma_addr >> 8));
176 }
177
178 /**
179  * iwl_rx_queue_restock - refill RX queue from pre-allocated pool
180  *
181  * If there are slots in the RX queue that need to be restocked,
182  * and we have free pre-allocated buffers, fill the ranks as much
183  * as we can, pulling from rx_free.
184  *
185  * This moves the 'write' index forward to catch up with 'processed', and
186  * also updates the memory address in the firmware to reference the new
187  * target buffer.
188  */
189 int iwl_rx_queue_restock(struct iwl_priv *priv)
190 {
191         struct iwl_rx_queue *rxq = &priv->rxq;
192         struct list_head *element;
193         struct iwl_rx_mem_buffer *rxb;
194         unsigned long flags;
195         int write;
196         int ret = 0;
197
198         spin_lock_irqsave(&rxq->lock, flags);
199         write = rxq->write & ~0x7;
200         while ((iwl_rx_queue_space(rxq) > 0) && (rxq->free_count)) {
201                 /* Get next free Rx buffer, remove from free list */
202                 element = rxq->rx_free.next;
203                 rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
204                 list_del(element);
205
206                 /* Point to Rx buffer via next RBD in circular buffer */
207                 rxq->bd[rxq->write] = iwl_dma_addr2rbd_ptr(priv, rxb->dma_addr);
208                 rxq->queue[rxq->write] = rxb;
209                 rxq->write = (rxq->write + 1) & RX_QUEUE_MASK;
210                 rxq->free_count--;
211         }
212         spin_unlock_irqrestore(&rxq->lock, flags);
213         /* If the pre-allocated buffer pool is dropping low, schedule to
214          * refill it */
215         if (rxq->free_count <= RX_LOW_WATERMARK)
216                 queue_work(priv->workqueue, &priv->rx_replenish);
217
218
219         /* If we've added more space for the firmware to place data, tell it.
220          * Increment device's write pointer in multiples of 8. */
221         if ((write != (rxq->write & ~0x7))
222             || (abs(rxq->write - rxq->read) > 7)) {
223                 spin_lock_irqsave(&rxq->lock, flags);
224                 rxq->need_update = 1;
225                 spin_unlock_irqrestore(&rxq->lock, flags);
226                 ret = iwl_rx_queue_update_write_ptr(priv, rxq);
227         }
228
229         return ret;
230 }
231 EXPORT_SYMBOL(iwl_rx_queue_restock);
232
233
234 /**
235  * iwl_rx_replenish - Move all used packet from rx_used to rx_free
236  *
237  * When moving to rx_free an SKB is allocated for the slot.
238  *
239  * Also restock the Rx queue via iwl_rx_queue_restock.
240  * This is called as a scheduled work item (except for during initialization)
241  */
242 void iwl_rx_allocate(struct iwl_priv *priv)
243 {
244         struct iwl_rx_queue *rxq = &priv->rxq;
245         struct list_head *element;
246         struct iwl_rx_mem_buffer *rxb;
247         unsigned long flags;
248         spin_lock_irqsave(&rxq->lock, flags);
249         while (!list_empty(&rxq->rx_used)) {
250                 element = rxq->rx_used.next;
251                 rxb = list_entry(element, struct iwl_rx_mem_buffer, list);
252
253                 /* Alloc a new receive buffer */
254                 rxb->skb = alloc_skb(priv->hw_params.rx_buf_size,
255                                 __GFP_NOWARN | GFP_ATOMIC);
256                 if (!rxb->skb) {
257                         if (net_ratelimit())
258                                 printk(KERN_CRIT DRV_NAME
259                                        ": Can not allocate SKB buffers\n");
260                         /* We don't reschedule replenish work here -- we will
261                          * call the restock method and if it still needs
262                          * more buffers it will schedule replenish */
263                         break;
264                 }
265                 priv->alloc_rxb_skb++;
266                 list_del(element);
267
268                 /* Get physical address of RB/SKB */
269                 rxb->dma_addr =
270                     pci_map_single(priv->pci_dev, rxb->skb->data,
271                            priv->hw_params.rx_buf_size, PCI_DMA_FROMDEVICE);
272                 list_add_tail(&rxb->list, &rxq->rx_free);
273                 rxq->free_count++;
274         }
275         spin_unlock_irqrestore(&rxq->lock, flags);
276 }
277 EXPORT_SYMBOL(iwl_rx_allocate);
278
279 void iwl_rx_replenish(struct iwl_priv *priv)
280 {
281         unsigned long flags;
282
283         iwl_rx_allocate(priv);
284
285         spin_lock_irqsave(&priv->lock, flags);
286         iwl_rx_queue_restock(priv);
287         spin_unlock_irqrestore(&priv->lock, flags);
288 }
289 EXPORT_SYMBOL(iwl_rx_replenish);
290
291
292 /* Assumes that the skb field of the buffers in 'pool' is kept accurate.
293  * If an SKB has been detached, the POOL needs to have its SKB set to NULL
294  * This free routine walks the list of POOL entries and if SKB is set to
295  * non NULL it is unmapped and freed
296  */
297 void iwl_rx_queue_free(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
298 {
299         int i;
300         for (i = 0; i < RX_QUEUE_SIZE + RX_FREE_BUFFERS; i++) {
301                 if (rxq->pool[i].skb != NULL) {
302                         pci_unmap_single(priv->pci_dev,
303                                          rxq->pool[i].dma_addr,
304                                          priv->hw_params.rx_buf_size,
305                                          PCI_DMA_FROMDEVICE);
306                         dev_kfree_skb(rxq->pool[i].skb);
307                 }
308         }
309
310         pci_free_consistent(priv->pci_dev, 4 * RX_QUEUE_SIZE, rxq->bd,
311                             rxq->dma_addr);
312         rxq->bd = NULL;
313 }
314 EXPORT_SYMBOL(iwl_rx_queue_free);
315
316 int iwl_rx_queue_alloc(struct iwl_priv *priv)
317 {
318         struct iwl_rx_queue *rxq = &priv->rxq;
319         struct pci_dev *dev = priv->pci_dev;
320         int i;
321
322         spin_lock_init(&rxq->lock);
323         INIT_LIST_HEAD(&rxq->rx_free);
324         INIT_LIST_HEAD(&rxq->rx_used);
325
326         /* Alloc the circular buffer of Read Buffer Descriptors (RBDs) */
327         rxq->bd = pci_alloc_consistent(dev, 4 * RX_QUEUE_SIZE, &rxq->dma_addr);
328         if (!rxq->bd)
329                 return -ENOMEM;
330
331         /* Fill the rx_used queue with _all_ of the Rx buffers */
332         for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++)
333                 list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
334
335         /* Set us so that we have processed and used all buffers, but have
336          * not restocked the Rx queue with fresh buffers */
337         rxq->read = rxq->write = 0;
338         rxq->free_count = 0;
339         rxq->need_update = 0;
340         return 0;
341 }
342 EXPORT_SYMBOL(iwl_rx_queue_alloc);
343
344 void iwl_rx_queue_reset(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
345 {
346         unsigned long flags;
347         int i;
348         spin_lock_irqsave(&rxq->lock, flags);
349         INIT_LIST_HEAD(&rxq->rx_free);
350         INIT_LIST_HEAD(&rxq->rx_used);
351         /* Fill the rx_used queue with _all_ of the Rx buffers */
352         for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++) {
353                 /* In the reset function, these buffers may have been allocated
354                  * to an SKB, so we need to unmap and free potential storage */
355                 if (rxq->pool[i].skb != NULL) {
356                         pci_unmap_single(priv->pci_dev,
357                                          rxq->pool[i].dma_addr,
358                                          priv->hw_params.rx_buf_size,
359                                          PCI_DMA_FROMDEVICE);
360                         priv->alloc_rxb_skb--;
361                         dev_kfree_skb(rxq->pool[i].skb);
362                         rxq->pool[i].skb = NULL;
363                 }
364                 list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
365         }
366
367         /* Set us so that we have processed and used all buffers, but have
368          * not restocked the Rx queue with fresh buffers */
369         rxq->read = rxq->write = 0;
370         rxq->free_count = 0;
371         spin_unlock_irqrestore(&rxq->lock, flags);
372 }
373 EXPORT_SYMBOL(iwl_rx_queue_reset);
374
375 int iwl_rx_init(struct iwl_priv *priv, struct iwl_rx_queue *rxq)
376 {
377         int ret;
378         unsigned long flags;
379         unsigned int rb_size;
380
381         spin_lock_irqsave(&priv->lock, flags);
382         ret = iwl_grab_nic_access(priv);
383         if (ret) {
384                 spin_unlock_irqrestore(&priv->lock, flags);
385                 return ret;
386         }
387
388         if (priv->cfg->mod_params->amsdu_size_8K)
389                 rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_8K;
390         else
391                 rb_size = FH_RCSR_RX_CONFIG_REG_VAL_RB_SIZE_4K;
392
393         /* Stop Rx DMA */
394         iwl_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
395
396         /* Reset driver's Rx queue write index */
397         iwl_write_direct32(priv, FH_RSCSR_CHNL0_RBDCB_WPTR_REG, 0);
398
399         /* Tell device where to find RBD circular buffer in DRAM */
400         iwl_write_direct32(priv, FH_RSCSR_CHNL0_RBDCB_BASE_REG,
401                            rxq->dma_addr >> 8);
402
403         /* Tell device where in DRAM to update its Rx status */
404         iwl_write_direct32(priv, FH_RSCSR_CHNL0_STTS_WPTR_REG,
405                            (priv->shared_phys + priv->rb_closed_offset) >> 4);
406
407         /* Enable Rx DMA, enable host interrupt, Rx buffer size 4k, 256 RBDs */
408         iwl_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG,
409                            FH_RCSR_RX_CONFIG_CHNL_EN_ENABLE_VAL |
410                            FH_RCSR_CHNL0_RX_CONFIG_IRQ_DEST_INT_HOST_VAL |
411                            rb_size |
412                              /* 0x10 << 4 | */
413                            (RX_QUEUE_SIZE_LOG <<
414                               FH_RCSR_RX_CONFIG_RBDCB_SIZE_BITSHIFT));
415
416         /*
417          * iwl_write32(priv,CSR_INT_COAL_REG,0);
418          */
419
420         iwl_release_nic_access(priv);
421         spin_unlock_irqrestore(&priv->lock, flags);
422
423         return 0;
424 }
425
426 int iwl_rxq_stop(struct iwl_priv *priv)
427 {
428         int ret;
429         unsigned long flags;
430
431         spin_lock_irqsave(&priv->lock, flags);
432         ret = iwl_grab_nic_access(priv);
433         if (unlikely(ret)) {
434                 spin_unlock_irqrestore(&priv->lock, flags);
435                 return ret;
436         }
437
438         /* stop Rx DMA */
439         iwl_write_direct32(priv, FH_MEM_RCSR_CHNL0_CONFIG_REG, 0);
440         ret = iwl_poll_direct_bit(priv, FH_MEM_RSSR_RX_STATUS_REG,
441                                      (1 << 24), 1000);
442         if (ret < 0)
443                 IWL_ERROR("Can't stop Rx DMA.\n");
444
445         iwl_release_nic_access(priv);
446         spin_unlock_irqrestore(&priv->lock, flags);
447
448         return 0;
449 }
450 EXPORT_SYMBOL(iwl_rxq_stop);
451
452 void iwl_rx_missed_beacon_notif(struct iwl_priv *priv,
453                                 struct iwl_rx_mem_buffer *rxb)
454
455 {
456         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
457         struct iwl4965_missed_beacon_notif *missed_beacon;
458
459         missed_beacon = &pkt->u.missed_beacon;
460         if (le32_to_cpu(missed_beacon->consequtive_missed_beacons) > 5) {
461                 IWL_DEBUG_CALIB("missed bcn cnsq %d totl %d rcd %d expctd %d\n",
462                     le32_to_cpu(missed_beacon->consequtive_missed_beacons),
463                     le32_to_cpu(missed_beacon->total_missed_becons),
464                     le32_to_cpu(missed_beacon->num_recvd_beacons),
465                     le32_to_cpu(missed_beacon->num_expected_beacons));
466                 if (!test_bit(STATUS_SCANNING, &priv->status))
467                         iwl_init_sensitivity(priv);
468         }
469 }
470 EXPORT_SYMBOL(iwl_rx_missed_beacon_notif);
471
472 int iwl_rx_agg_start(struct iwl_priv *priv, const u8 *addr, int tid, u16 ssn)
473 {
474         unsigned long flags;
475         int sta_id;
476
477         sta_id = iwl_find_station(priv, addr);
478         if (sta_id == IWL_INVALID_STATION)
479                 return -ENXIO;
480
481         spin_lock_irqsave(&priv->sta_lock, flags);
482         priv->stations[sta_id].sta.station_flags_msk = 0;
483         priv->stations[sta_id].sta.sta.modify_mask = STA_MODIFY_ADDBA_TID_MSK;
484         priv->stations[sta_id].sta.add_immediate_ba_tid = (u8)tid;
485         priv->stations[sta_id].sta.add_immediate_ba_ssn = cpu_to_le16(ssn);
486         priv->stations[sta_id].sta.mode = STA_CONTROL_MODIFY_MSK;
487         spin_unlock_irqrestore(&priv->sta_lock, flags);
488
489         return iwl_send_add_sta(priv, &priv->stations[sta_id].sta,
490                                         CMD_ASYNC);
491 }
492 EXPORT_SYMBOL(iwl_rx_agg_start);
493
494 int iwl_rx_agg_stop(struct iwl_priv *priv, const u8 *addr, int tid)
495 {
496         unsigned long flags;
497         int sta_id;
498
499         sta_id = iwl_find_station(priv, addr);
500         if (sta_id == IWL_INVALID_STATION)
501                 return -ENXIO;
502
503         spin_lock_irqsave(&priv->sta_lock, flags);
504         priv->stations[sta_id].sta.station_flags_msk = 0;
505         priv->stations[sta_id].sta.sta.modify_mask = STA_MODIFY_DELBA_TID_MSK;
506         priv->stations[sta_id].sta.remove_immediate_ba_tid = (u8)tid;
507         priv->stations[sta_id].sta.mode = STA_CONTROL_MODIFY_MSK;
508         spin_unlock_irqrestore(&priv->sta_lock, flags);
509
510         return iwl_send_add_sta(priv, &priv->stations[sta_id].sta,
511                                         CMD_ASYNC);
512 }
513 EXPORT_SYMBOL(iwl_rx_agg_stop);
514
515
516 /* Calculate noise level, based on measurements during network silence just
517  *   before arriving beacon.  This measurement can be done only if we know
518  *   exactly when to expect beacons, therefore only when we're associated. */
519 static void iwl_rx_calc_noise(struct iwl_priv *priv)
520 {
521         struct statistics_rx_non_phy *rx_info
522                                 = &(priv->statistics.rx.general);
523         int num_active_rx = 0;
524         int total_silence = 0;
525         int bcn_silence_a =
526                 le32_to_cpu(rx_info->beacon_silence_rssi_a) & IN_BAND_FILTER;
527         int bcn_silence_b =
528                 le32_to_cpu(rx_info->beacon_silence_rssi_b) & IN_BAND_FILTER;
529         int bcn_silence_c =
530                 le32_to_cpu(rx_info->beacon_silence_rssi_c) & IN_BAND_FILTER;
531
532         if (bcn_silence_a) {
533                 total_silence += bcn_silence_a;
534                 num_active_rx++;
535         }
536         if (bcn_silence_b) {
537                 total_silence += bcn_silence_b;
538                 num_active_rx++;
539         }
540         if (bcn_silence_c) {
541                 total_silence += bcn_silence_c;
542                 num_active_rx++;
543         }
544
545         /* Average among active antennas */
546         if (num_active_rx)
547                 priv->last_rx_noise = (total_silence / num_active_rx) - 107;
548         else
549                 priv->last_rx_noise = IWL_NOISE_MEAS_NOT_AVAILABLE;
550
551         IWL_DEBUG_CALIB("inband silence a %u, b %u, c %u, dBm %d\n",
552                         bcn_silence_a, bcn_silence_b, bcn_silence_c,
553                         priv->last_rx_noise);
554 }
555
556 #define REG_RECALIB_PERIOD (60)
557
558 void iwl_rx_statistics(struct iwl_priv *priv,
559                               struct iwl_rx_mem_buffer *rxb)
560 {
561         int change;
562         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
563
564         IWL_DEBUG_RX("Statistics notification received (%d vs %d).\n",
565                      (int)sizeof(priv->statistics), pkt->len);
566
567         change = ((priv->statistics.general.temperature !=
568                    pkt->u.stats.general.temperature) ||
569                   ((priv->statistics.flag &
570                     STATISTICS_REPLY_FLG_FAT_MODE_MSK) !=
571                    (pkt->u.stats.flag & STATISTICS_REPLY_FLG_FAT_MODE_MSK)));
572
573         memcpy(&priv->statistics, &pkt->u.stats, sizeof(priv->statistics));
574
575         set_bit(STATUS_STATISTICS, &priv->status);
576
577         /* Reschedule the statistics timer to occur in
578          * REG_RECALIB_PERIOD seconds to ensure we get a
579          * thermal update even if the uCode doesn't give
580          * us one */
581         mod_timer(&priv->statistics_periodic, jiffies +
582                   msecs_to_jiffies(REG_RECALIB_PERIOD * 1000));
583
584         if (unlikely(!test_bit(STATUS_SCANNING, &priv->status)) &&
585             (pkt->hdr.cmd == STATISTICS_NOTIFICATION)) {
586                 iwl_rx_calc_noise(priv);
587                 queue_work(priv->workqueue, &priv->run_time_calib_work);
588         }
589
590         iwl_leds_background(priv);
591
592         if (priv->cfg->ops->lib->temperature && change)
593                 priv->cfg->ops->lib->temperature(priv);
594 }
595 EXPORT_SYMBOL(iwl_rx_statistics);
596
597 #define PERFECT_RSSI (-20) /* dBm */
598 #define WORST_RSSI (-95)   /* dBm */
599 #define RSSI_RANGE (PERFECT_RSSI - WORST_RSSI)
600
601 /* Calculate an indication of rx signal quality (a percentage, not dBm!).
602  * See http://www.ces.clemson.edu/linux/signal_quality.shtml for info
603  *   about formulas used below. */
604 static int iwl_calc_sig_qual(int rssi_dbm, int noise_dbm)
605 {
606         int sig_qual;
607         int degradation = PERFECT_RSSI - rssi_dbm;
608
609         /* If we get a noise measurement, use signal-to-noise ratio (SNR)
610          * as indicator; formula is (signal dbm - noise dbm).
611          * SNR at or above 40 is a great signal (100%).
612          * Below that, scale to fit SNR of 0 - 40 dB within 0 - 100% indicator.
613          * Weakest usable signal is usually 10 - 15 dB SNR. */
614         if (noise_dbm) {
615                 if (rssi_dbm - noise_dbm >= 40)
616                         return 100;
617                 else if (rssi_dbm < noise_dbm)
618                         return 0;
619                 sig_qual = ((rssi_dbm - noise_dbm) * 5) / 2;
620
621         /* Else use just the signal level.
622          * This formula is a least squares fit of data points collected and
623          *   compared with a reference system that had a percentage (%) display
624          *   for signal quality. */
625         } else
626                 sig_qual = (100 * (RSSI_RANGE * RSSI_RANGE) - degradation *
627                             (15 * RSSI_RANGE + 62 * degradation)) /
628                            (RSSI_RANGE * RSSI_RANGE);
629
630         if (sig_qual > 100)
631                 sig_qual = 100;
632         else if (sig_qual < 1)
633                 sig_qual = 0;
634
635         return sig_qual;
636 }
637
638 #ifdef CONFIG_IWLWIFI_DEBUG
639
640 /**
641  * iwl_dbg_report_frame - dump frame to syslog during debug sessions
642  *
643  * You may hack this function to show different aspects of received frames,
644  * including selective frame dumps.
645  * group100 parameter selects whether to show 1 out of 100 good frames.
646  *
647  * TODO:  This was originally written for 3945, need to audit for
648  *        proper operation with 4965.
649  */
650 static void iwl_dbg_report_frame(struct iwl_priv *priv,
651                       struct iwl_rx_packet *pkt,
652                       struct ieee80211_hdr *header, int group100)
653 {
654         u32 to_us;
655         u32 print_summary = 0;
656         u32 print_dump = 0;     /* set to 1 to dump all frames' contents */
657         u32 hundred = 0;
658         u32 dataframe = 0;
659         __le16 fc;
660         u16 seq_ctl;
661         u16 channel;
662         u16 phy_flags;
663         int rate_sym;
664         u16 length;
665         u16 status;
666         u16 bcn_tmr;
667         u32 tsf_low;
668         u64 tsf;
669         u8 rssi;
670         u8 agc;
671         u16 sig_avg;
672         u16 noise_diff;
673         struct iwl4965_rx_frame_stats *rx_stats = IWL_RX_STATS(pkt);
674         struct iwl4965_rx_frame_hdr *rx_hdr = IWL_RX_HDR(pkt);
675         struct iwl4965_rx_frame_end *rx_end = IWL_RX_END(pkt);
676         u8 *data = IWL_RX_DATA(pkt);
677
678         if (likely(!(priv->debug_level & IWL_DL_RX)))
679                 return;
680
681         /* MAC header */
682         fc = header->frame_control;
683         seq_ctl = le16_to_cpu(header->seq_ctrl);
684
685         /* metadata */
686         channel = le16_to_cpu(rx_hdr->channel);
687         phy_flags = le16_to_cpu(rx_hdr->phy_flags);
688         rate_sym = rx_hdr->rate;
689         length = le16_to_cpu(rx_hdr->len);
690
691         /* end-of-frame status and timestamp */
692         status = le32_to_cpu(rx_end->status);
693         bcn_tmr = le32_to_cpu(rx_end->beacon_timestamp);
694         tsf_low = le64_to_cpu(rx_end->timestamp) & 0x0ffffffff;
695         tsf = le64_to_cpu(rx_end->timestamp);
696
697         /* signal statistics */
698         rssi = rx_stats->rssi;
699         agc = rx_stats->agc;
700         sig_avg = le16_to_cpu(rx_stats->sig_avg);
701         noise_diff = le16_to_cpu(rx_stats->noise_diff);
702
703         to_us = !compare_ether_addr(header->addr1, priv->mac_addr);
704
705         /* if data frame is to us and all is good,
706          *   (optionally) print summary for only 1 out of every 100 */
707         if (to_us && (fc & ~cpu_to_le16(IEEE80211_FCTL_PROTECTED)) ==
708             cpu_to_le16(IEEE80211_FCTL_FROMDS | IEEE80211_FTYPE_DATA)) {
709                 dataframe = 1;
710                 if (!group100)
711                         print_summary = 1;      /* print each frame */
712                 else if (priv->framecnt_to_us < 100) {
713                         priv->framecnt_to_us++;
714                         print_summary = 0;
715                 } else {
716                         priv->framecnt_to_us = 0;
717                         print_summary = 1;
718                         hundred = 1;
719                 }
720         } else {
721                 /* print summary for all other frames */
722                 print_summary = 1;
723         }
724
725         if (print_summary) {
726                 char *title;
727                 int rate_idx;
728                 u32 bitrate;
729
730                 if (hundred)
731                         title = "100Frames";
732                 else if (ieee80211_has_retry(fc))
733                         title = "Retry";
734                 else if (ieee80211_is_assoc_resp(fc))
735                         title = "AscRsp";
736                 else if (ieee80211_is_reassoc_resp(fc))
737                         title = "RasRsp";
738                 else if (ieee80211_is_probe_resp(fc)) {
739                         title = "PrbRsp";
740                         print_dump = 1; /* dump frame contents */
741                 } else if (ieee80211_is_beacon(fc)) {
742                         title = "Beacon";
743                         print_dump = 1; /* dump frame contents */
744                 } else if (ieee80211_is_atim(fc))
745                         title = "ATIM";
746                 else if (ieee80211_is_auth(fc))
747                         title = "Auth";
748                 else if (ieee80211_is_deauth(fc))
749                         title = "DeAuth";
750                 else if (ieee80211_is_disassoc(fc))
751                         title = "DisAssoc";
752                 else
753                         title = "Frame";
754
755                 rate_idx = iwl_hwrate_to_plcp_idx(rate_sym);
756                 if (unlikely(rate_idx == -1))
757                         bitrate = 0;
758                 else
759                         bitrate = iwl_rates[rate_idx].ieee / 2;
760
761                 /* print frame summary.
762                  * MAC addresses show just the last byte (for brevity),
763                  *    but you can hack it to show more, if you'd like to. */
764                 if (dataframe)
765                         IWL_DEBUG_RX("%s: mhd=0x%04x, dst=0x%02x, "
766                                      "len=%u, rssi=%d, chnl=%d, rate=%u, \n",
767                                      title, le16_to_cpu(fc), header->addr1[5],
768                                      length, rssi, channel, bitrate);
769                 else {
770                         /* src/dst addresses assume managed mode */
771                         IWL_DEBUG_RX("%s: 0x%04x, dst=0x%02x, "
772                                      "src=0x%02x, rssi=%u, tim=%lu usec, "
773                                      "phy=0x%02x, chnl=%d\n",
774                                      title, le16_to_cpu(fc), header->addr1[5],
775                                      header->addr3[5], rssi,
776                                      tsf_low - priv->scan_start_tsf,
777                                      phy_flags, channel);
778                 }
779         }
780         if (print_dump)
781                 iwl_print_hex_dump(priv, IWL_DL_RX, data, length);
782 }
783 #else
784 static inline void iwl_dbg_report_frame(struct iwl_priv *priv,
785                                             struct iwl_rx_packet *pkt,
786                                             struct ieee80211_hdr *header,
787                                             int group100)
788 {
789 }
790 #endif
791
792 static void iwl_add_radiotap(struct iwl_priv *priv,
793                                  struct sk_buff *skb,
794                                  struct iwl4965_rx_phy_res *rx_start,
795                                  struct ieee80211_rx_status *stats,
796                                  u32 ampdu_status)
797 {
798         s8 signal = stats->signal;
799         s8 noise = 0;
800         int rate = stats->rate_idx;
801         u64 tsf = stats->mactime;
802         __le16 antenna;
803         __le16 phy_flags_hw = rx_start->phy_flags;
804         struct iwl4965_rt_rx_hdr {
805                 struct ieee80211_radiotap_header rt_hdr;
806                 __le64 rt_tsf;          /* TSF */
807                 u8 rt_flags;            /* radiotap packet flags */
808                 u8 rt_rate;             /* rate in 500kb/s */
809                 __le16 rt_channelMHz;   /* channel in MHz */
810                 __le16 rt_chbitmask;    /* channel bitfield */
811                 s8 rt_dbmsignal;        /* signal in dBm, kluged to signed */
812                 s8 rt_dbmnoise;
813                 u8 rt_antenna;          /* antenna number */
814         } __attribute__ ((packed)) *iwl4965_rt;
815
816         /* TODO: We won't have enough headroom for HT frames. Fix it later. */
817         if (skb_headroom(skb) < sizeof(*iwl4965_rt)) {
818                 if (net_ratelimit())
819                         printk(KERN_ERR "not enough headroom [%d] for "
820                                "radiotap head [%zd]\n",
821                                skb_headroom(skb), sizeof(*iwl4965_rt));
822                 return;
823         }
824
825         /* put radiotap header in front of 802.11 header and data */
826         iwl4965_rt = (void *)skb_push(skb, sizeof(*iwl4965_rt));
827
828         /* initialise radiotap header */
829         iwl4965_rt->rt_hdr.it_version = PKTHDR_RADIOTAP_VERSION;
830         iwl4965_rt->rt_hdr.it_pad = 0;
831
832         /* total header + data */
833         put_unaligned_le16(sizeof(*iwl4965_rt), &iwl4965_rt->rt_hdr.it_len);
834
835         /* Indicate all the fields we add to the radiotap header */
836         put_unaligned_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_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_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_5GHZ,
857                                    &iwl4965_rt->rt_chbitmask);
858         else if (phy_flags_hw & RX_RES_PHY_FLAGS_MOD_CCK_MSK)
859                 put_unaligned_le16(IEEE80211_CHAN_CCK | IEEE80211_CHAN_2GHZ,
860                                    &iwl4965_rt->rt_chbitmask);
861         else    /* 802.11g */
862                 put_unaligned_le16(IEEE80211_CHAN_OFDM | IEEE80211_CHAN_2GHZ,
863                                    &iwl4965_rt->rt_chbitmask);
864
865         if (rate == -1)
866                 iwl4965_rt->rt_rate = 0;
867         else
868                 iwl4965_rt->rt_rate = iwl_rates[rate].ieee;
869
870         /*
871          * "antenna number"
872          *
873          * It seems that the antenna field in the phy flags value
874          * is actually a bitfield. This is undefined by radiotap,
875          * it wants an actual antenna number but I always get "7"
876          * for most legacy frames I receive indicating that the
877          * same frame was received on all three RX chains.
878          *
879          * I think this field should be removed in favour of a
880          * new 802.11n radiotap field "RX chains" that is defined
881          * as a bitmask.
882          */
883         antenna = phy_flags_hw & RX_RES_PHY_FLAGS_ANTENNA_MSK;
884         iwl4965_rt->rt_antenna = le16_to_cpu(antenna) >> 4;
885
886         /* set the preamble flag if appropriate */
887         if (phy_flags_hw & RX_RES_PHY_FLAGS_SHORT_PREAMBLE_MSK)
888                 iwl4965_rt->rt_flags |= IEEE80211_RADIOTAP_F_SHORTPRE;
889
890         stats->flag |= RX_FLAG_RADIOTAP;
891 }
892
893 static void iwl_update_rx_stats(struct iwl_priv *priv, u16 fc, u16 len)
894 {
895         /* 0 - mgmt, 1 - cnt, 2 - data */
896         int idx = (fc & IEEE80211_FCTL_FTYPE) >> 2;
897         priv->rx_stats[idx].cnt++;
898         priv->rx_stats[idx].bytes += len;
899 }
900
901 /*
902  * returns non-zero if packet should be dropped
903  */
904 static int iwl_set_decrypted_flag(struct iwl_priv *priv,
905                                       struct ieee80211_hdr *hdr,
906                                       u32 decrypt_res,
907                                       struct ieee80211_rx_status *stats)
908 {
909         u16 fc = le16_to_cpu(hdr->frame_control);
910
911         if (priv->active_rxon.filter_flags & RXON_FILTER_DIS_DECRYPT_MSK)
912                 return 0;
913
914         if (!(fc & IEEE80211_FCTL_PROTECTED))
915                 return 0;
916
917         IWL_DEBUG_RX("decrypt_res:0x%x\n", decrypt_res);
918         switch (decrypt_res & RX_RES_STATUS_SEC_TYPE_MSK) {
919         case RX_RES_STATUS_SEC_TYPE_TKIP:
920                 /* The uCode has got a bad phase 1 Key, pushes the packet.
921                  * Decryption will be done in SW. */
922                 if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
923                     RX_RES_STATUS_BAD_KEY_TTAK)
924                         break;
925
926         case RX_RES_STATUS_SEC_TYPE_WEP:
927                 if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
928                     RX_RES_STATUS_BAD_ICV_MIC) {
929                         /* bad ICV, the packet is destroyed since the
930                          * decryption is inplace, drop it */
931                         IWL_DEBUG_RX("Packet destroyed\n");
932                         return -1;
933                 }
934         case RX_RES_STATUS_SEC_TYPE_CCMP:
935                 if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
936                     RX_RES_STATUS_DECRYPT_OK) {
937                         IWL_DEBUG_RX("hw decrypt successfully!!!\n");
938                         stats->flag |= RX_FLAG_DECRYPTED;
939                 }
940                 break;
941
942         default:
943                 break;
944         }
945         return 0;
946 }
947
948 static u32 iwl_translate_rx_status(struct iwl_priv *priv, u32 decrypt_in)
949 {
950         u32 decrypt_out = 0;
951
952         if ((decrypt_in & RX_RES_STATUS_STATION_FOUND) ==
953                                         RX_RES_STATUS_STATION_FOUND)
954                 decrypt_out |= (RX_RES_STATUS_STATION_FOUND |
955                                 RX_RES_STATUS_NO_STATION_INFO_MISMATCH);
956
957         decrypt_out |= (decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK);
958
959         /* packet was not encrypted */
960         if ((decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) ==
961                                         RX_RES_STATUS_SEC_TYPE_NONE)
962                 return decrypt_out;
963
964         /* packet was encrypted with unknown alg */
965         if ((decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) ==
966                                         RX_RES_STATUS_SEC_TYPE_ERR)
967                 return decrypt_out;
968
969         /* decryption was not done in HW */
970         if ((decrypt_in & RX_MPDU_RES_STATUS_DEC_DONE_MSK) !=
971                                         RX_MPDU_RES_STATUS_DEC_DONE_MSK)
972                 return decrypt_out;
973
974         switch (decrypt_in & RX_RES_STATUS_SEC_TYPE_MSK) {
975
976         case RX_RES_STATUS_SEC_TYPE_CCMP:
977                 /* alg is CCM: check MIC only */
978                 if (!(decrypt_in & RX_MPDU_RES_STATUS_MIC_OK))
979                         /* Bad MIC */
980                         decrypt_out |= RX_RES_STATUS_BAD_ICV_MIC;
981                 else
982                         decrypt_out |= RX_RES_STATUS_DECRYPT_OK;
983
984                 break;
985
986         case RX_RES_STATUS_SEC_TYPE_TKIP:
987                 if (!(decrypt_in & RX_MPDU_RES_STATUS_TTAK_OK)) {
988                         /* Bad TTAK */
989                         decrypt_out |= RX_RES_STATUS_BAD_KEY_TTAK;
990                         break;
991                 }
992                 /* fall through if TTAK OK */
993         default:
994                 if (!(decrypt_in & RX_MPDU_RES_STATUS_ICV_OK))
995                         decrypt_out |= RX_RES_STATUS_BAD_ICV_MIC;
996                 else
997                         decrypt_out |= RX_RES_STATUS_DECRYPT_OK;
998                 break;
999         };
1000
1001         IWL_DEBUG_RX("decrypt_in:0x%x  decrypt_out = 0x%x\n",
1002                                         decrypt_in, decrypt_out);
1003
1004         return decrypt_out;
1005 }
1006
1007 static void iwl_pass_packet_to_mac80211(struct iwl_priv *priv,
1008                                        int include_phy,
1009                                        struct iwl_rx_mem_buffer *rxb,
1010                                        struct ieee80211_rx_status *stats)
1011 {
1012         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
1013         struct iwl4965_rx_phy_res *rx_start = (include_phy) ?
1014             (struct iwl4965_rx_phy_res *)&(pkt->u.raw[0]) : NULL;
1015         struct ieee80211_hdr *hdr;
1016         u16 len;
1017         __le32 *rx_end;
1018         unsigned int skblen;
1019         u32 ampdu_status;
1020         u32 ampdu_status_legacy;
1021
1022         if (!include_phy && priv->last_phy_res[0])
1023                 rx_start = (struct iwl4965_rx_phy_res *)&priv->last_phy_res[1];
1024
1025         if (!rx_start) {
1026                 IWL_ERROR("MPDU frame without a PHY data\n");
1027                 return;
1028         }
1029         if (include_phy) {
1030                 hdr = (struct ieee80211_hdr *)((u8 *) &rx_start[1] +
1031                                                rx_start->cfg_phy_cnt);
1032
1033                 len = le16_to_cpu(rx_start->byte_count);
1034
1035                 rx_end = (__le32 *) ((u8 *) &pkt->u.raw[0] +
1036                                   sizeof(struct iwl4965_rx_phy_res) +
1037                                   rx_start->cfg_phy_cnt + len);
1038
1039         } else {
1040                 struct iwl4965_rx_mpdu_res_start *amsdu =
1041                     (struct iwl4965_rx_mpdu_res_start *)pkt->u.raw;
1042
1043                 hdr = (struct ieee80211_hdr *)(pkt->u.raw +
1044                                sizeof(struct iwl4965_rx_mpdu_res_start));
1045                 len =  le16_to_cpu(amsdu->byte_count);
1046                 rx_start->byte_count = amsdu->byte_count;
1047                 rx_end = (__le32 *) (((u8 *) hdr) + len);
1048         }
1049
1050         ampdu_status = le32_to_cpu(*rx_end);
1051         skblen = ((u8 *) rx_end - (u8 *) &pkt->u.raw[0]) + sizeof(u32);
1052
1053         if (!include_phy) {
1054                 /* New status scheme, need to translate */
1055                 ampdu_status_legacy = ampdu_status;
1056                 ampdu_status = iwl_translate_rx_status(priv, ampdu_status);
1057         }
1058
1059         /* start from MAC */
1060         skb_reserve(rxb->skb, (void *)hdr - (void *)pkt);
1061         skb_put(rxb->skb, len); /* end where data ends */
1062
1063         /* We only process data packets if the interface is open */
1064         if (unlikely(!priv->is_open)) {
1065                 IWL_DEBUG_DROP_LIMIT
1066                     ("Dropping packet while interface is not open.\n");
1067                 return;
1068         }
1069
1070         hdr = (struct ieee80211_hdr *)rxb->skb->data;
1071
1072         /*  in case of HW accelerated crypto and bad decryption, drop */
1073         if (!priv->hw_params.sw_crypto &&
1074             iwl_set_decrypted_flag(priv, hdr, ampdu_status, stats))
1075                 return;
1076
1077         if (priv->add_radiotap)
1078                 iwl_add_radiotap(priv, rxb->skb, rx_start, stats, ampdu_status);
1079
1080         iwl_update_rx_stats(priv, le16_to_cpu(hdr->frame_control), len);
1081         ieee80211_rx_irqsafe(priv->hw, rxb->skb, stats);
1082         priv->alloc_rxb_skb--;
1083         rxb->skb = NULL;
1084 }
1085
1086 /* Calc max signal level (dBm) among 3 possible receivers */
1087 static int iwl_calc_rssi(struct iwl_priv *priv,
1088                              struct iwl4965_rx_phy_res *rx_resp)
1089 {
1090         /* data from PHY/DSP regarding signal strength, etc.,
1091          *   contents are always there, not configurable by host.  */
1092         struct iwl4965_rx_non_cfg_phy *ncphy =
1093             (struct iwl4965_rx_non_cfg_phy *)rx_resp->non_cfg_phy;
1094         u32 agc = (le16_to_cpu(ncphy->agc_info) & IWL_AGC_DB_MASK)
1095                         >> IWL_AGC_DB_POS;
1096
1097         u32 valid_antennae =
1098             (le16_to_cpu(rx_resp->phy_flags) & RX_PHY_FLAGS_ANTENNAE_MASK)
1099                         >> RX_PHY_FLAGS_ANTENNAE_OFFSET;
1100         u8 max_rssi = 0;
1101         u32 i;
1102
1103         /* Find max rssi among 3 possible receivers.
1104          * These values are measured by the digital signal processor (DSP).
1105          * They should stay fairly constant even as the signal strength varies,
1106          *   if the radio's automatic gain control (AGC) is working right.
1107          * AGC value (see below) will provide the "interesting" info. */
1108         for (i = 0; i < 3; i++)
1109                 if (valid_antennae & (1 << i))
1110                         max_rssi = max(ncphy->rssi_info[i << 1], max_rssi);
1111
1112         IWL_DEBUG_STATS("Rssi In A %d B %d C %d Max %d AGC dB %d\n",
1113                 ncphy->rssi_info[0], ncphy->rssi_info[2], ncphy->rssi_info[4],
1114                 max_rssi, agc);
1115
1116         /* dBm = max_rssi dB - agc dB - constant.
1117          * Higher AGC (higher radio gain) means lower signal. */
1118         return max_rssi - agc - IWL_RSSI_OFFSET;
1119 }
1120
1121 static void iwl_sta_modify_ps_wake(struct iwl_priv *priv, int sta_id)
1122 {
1123         unsigned long flags;
1124
1125         spin_lock_irqsave(&priv->sta_lock, flags);
1126         priv->stations[sta_id].sta.station_flags &= ~STA_FLG_PWR_SAVE_MSK;
1127         priv->stations[sta_id].sta.station_flags_msk = STA_FLG_PWR_SAVE_MSK;
1128         priv->stations[sta_id].sta.sta.modify_mask = 0;
1129         priv->stations[sta_id].sta.mode = STA_CONTROL_MODIFY_MSK;
1130         spin_unlock_irqrestore(&priv->sta_lock, flags);
1131
1132         iwl_send_add_sta(priv, &priv->stations[sta_id].sta, CMD_ASYNC);
1133 }
1134
1135 static void iwl_update_ps_mode(struct iwl_priv *priv, u16 ps_bit, u8 *addr)
1136 {
1137         /* FIXME: need locking over ps_status ??? */
1138         u8 sta_id = iwl_find_station(priv, addr);
1139
1140         if (sta_id != IWL_INVALID_STATION) {
1141                 u8 sta_awake = priv->stations[sta_id].
1142                                 ps_status == STA_PS_STATUS_WAKE;
1143
1144                 if (sta_awake && ps_bit)
1145                         priv->stations[sta_id].ps_status = STA_PS_STATUS_SLEEP;
1146                 else if (!sta_awake && !ps_bit) {
1147                         iwl_sta_modify_ps_wake(priv, sta_id);
1148                         priv->stations[sta_id].ps_status = STA_PS_STATUS_WAKE;
1149                 }
1150         }
1151 }
1152
1153 /* This is necessary only for a number of statistics, see the caller. */
1154 static int iwl_is_network_packet(struct iwl_priv *priv,
1155                 struct ieee80211_hdr *header)
1156 {
1157         /* Filter incoming packets to determine if they are targeted toward
1158          * this network, discarding packets coming from ourselves */
1159         switch (priv->iw_mode) {
1160         case IEEE80211_IF_TYPE_IBSS: /* Header: Dest. | Source    | BSSID */
1161                 /* packets to our IBSS update information */
1162                 return !compare_ether_addr(header->addr3, priv->bssid);
1163         case IEEE80211_IF_TYPE_STA: /* Header: Dest. | AP{BSSID} | Source */
1164                 /* packets to our IBSS update information */
1165                 return !compare_ether_addr(header->addr2, priv->bssid);
1166         default:
1167                 return 1;
1168         }
1169 }
1170
1171 /* Called for REPLY_RX (legacy ABG frames), or
1172  * REPLY_RX_MPDU_CMD (HT high-throughput N frames). */
1173 void iwl_rx_reply_rx(struct iwl_priv *priv,
1174                                 struct iwl_rx_mem_buffer *rxb)
1175 {
1176         struct ieee80211_hdr *header;
1177         struct ieee80211_rx_status rx_status;
1178         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
1179         /* Use phy data (Rx signal strength, etc.) contained within
1180          *   this rx packet for legacy frames,
1181          *   or phy data cached from REPLY_RX_PHY_CMD for HT frames. */
1182         int include_phy = (pkt->hdr.cmd == REPLY_RX);
1183         struct iwl4965_rx_phy_res *rx_start = (include_phy) ?
1184                 (struct iwl4965_rx_phy_res *)&(pkt->u.raw[0]) :
1185                 (struct iwl4965_rx_phy_res *)&priv->last_phy_res[1];
1186         __le32 *rx_end;
1187         unsigned int len = 0;
1188         u16 fc;
1189         u8 network_packet;
1190
1191         rx_status.mactime = le64_to_cpu(rx_start->timestamp);
1192         rx_status.freq =
1193                 ieee80211_channel_to_frequency(le16_to_cpu(rx_start->channel));
1194         rx_status.band = (rx_start->phy_flags & RX_RES_PHY_FLAGS_BAND_24_MSK) ?
1195                                 IEEE80211_BAND_2GHZ : IEEE80211_BAND_5GHZ;
1196         rx_status.rate_idx =
1197                 iwl_hwrate_to_plcp_idx(le32_to_cpu(rx_start->rate_n_flags));
1198         if (rx_status.band == IEEE80211_BAND_5GHZ)
1199                 rx_status.rate_idx -= IWL_FIRST_OFDM_RATE;
1200
1201         rx_status.antenna = 0;
1202         rx_status.flag = 0;
1203         rx_status.flag |= RX_FLAG_TSFT;
1204
1205         if ((unlikely(rx_start->cfg_phy_cnt > 20))) {
1206                 IWL_DEBUG_DROP("dsp size out of range [0,20]: %d/n",
1207                                 rx_start->cfg_phy_cnt);
1208                 return;
1209         }
1210
1211         if (!include_phy) {
1212                 if (priv->last_phy_res[0])
1213                         rx_start = (struct iwl4965_rx_phy_res *)
1214                                 &priv->last_phy_res[1];
1215                 else
1216                         rx_start = NULL;
1217         }
1218
1219         if (!rx_start) {
1220                 IWL_ERROR("MPDU frame without a PHY data\n");
1221                 return;
1222         }
1223
1224         if (include_phy) {
1225                 header = (struct ieee80211_hdr *)((u8 *) &rx_start[1]
1226                                                   + rx_start->cfg_phy_cnt);
1227
1228                 len = le16_to_cpu(rx_start->byte_count);
1229                 rx_end = (__le32 *)(pkt->u.raw + rx_start->cfg_phy_cnt +
1230                                   sizeof(struct iwl4965_rx_phy_res) + len);
1231         } else {
1232                 struct iwl4965_rx_mpdu_res_start *amsdu =
1233                         (struct iwl4965_rx_mpdu_res_start *)pkt->u.raw;
1234
1235                 header = (void *)(pkt->u.raw +
1236                         sizeof(struct iwl4965_rx_mpdu_res_start));
1237                 len = le16_to_cpu(amsdu->byte_count);
1238                 rx_end = (__le32 *) (pkt->u.raw +
1239                         sizeof(struct iwl4965_rx_mpdu_res_start) + len);
1240         }
1241
1242         if (!(*rx_end & RX_RES_STATUS_NO_CRC32_ERROR) ||
1243             !(*rx_end & RX_RES_STATUS_NO_RXE_OVERFLOW)) {
1244                 IWL_DEBUG_RX("Bad CRC or FIFO: 0x%08X.\n",
1245                                 le32_to_cpu(*rx_end));
1246                 return;
1247         }
1248
1249         priv->ucode_beacon_time = le32_to_cpu(rx_start->beacon_time_stamp);
1250
1251         /* Find max signal strength (dBm) among 3 antenna/receiver chains */
1252         rx_status.signal = iwl_calc_rssi(priv, rx_start);
1253
1254         /* Meaningful noise values are available only from beacon statistics,
1255          *   which are gathered only when associated, and indicate noise
1256          *   only for the associated network channel ...
1257          * Ignore these noise values while scanning (other channels) */
1258         if (iwl_is_associated(priv) &&
1259             !test_bit(STATUS_SCANNING, &priv->status)) {
1260                 rx_status.noise = priv->last_rx_noise;
1261                 rx_status.qual = iwl_calc_sig_qual(rx_status.signal,
1262                                                          rx_status.noise);
1263         } else {
1264                 rx_status.noise = IWL_NOISE_MEAS_NOT_AVAILABLE;
1265                 rx_status.qual = iwl_calc_sig_qual(rx_status.signal, 0);
1266         }
1267
1268         /* Reset beacon noise level if not associated. */
1269         if (!iwl_is_associated(priv))
1270                 priv->last_rx_noise = IWL_NOISE_MEAS_NOT_AVAILABLE;
1271
1272         /* Set "1" to report good data frames in groups of 100 */
1273         /* FIXME: need to optimze the call: */
1274         iwl_dbg_report_frame(priv, pkt, header, 1);
1275
1276         IWL_DEBUG_STATS_LIMIT("Rssi %d, noise %d, qual %d, TSF %llu\n",
1277                 rx_status.signal, rx_status.noise, rx_status.signal,
1278                 (unsigned long long)rx_status.mactime);
1279
1280         /* Take shortcut when only in monitor mode */
1281         if (priv->iw_mode == IEEE80211_IF_TYPE_MNTR) {
1282                 iwl_pass_packet_to_mac80211(priv, include_phy,
1283                                                  rxb, &rx_status);
1284                 return;
1285         }
1286
1287         network_packet = iwl_is_network_packet(priv, header);
1288         if (network_packet) {
1289                 priv->last_rx_rssi = rx_status.signal;
1290                 priv->last_beacon_time =  priv->ucode_beacon_time;
1291                 priv->last_tsf = le64_to_cpu(rx_start->timestamp);
1292         }
1293
1294         fc = le16_to_cpu(header->frame_control);
1295         switch (fc & IEEE80211_FCTL_FTYPE) {
1296         case IEEE80211_FTYPE_MGMT:
1297         case IEEE80211_FTYPE_DATA:
1298                 if (priv->iw_mode == IEEE80211_IF_TYPE_AP)
1299                         iwl_update_ps_mode(priv, fc  & IEEE80211_FCTL_PM,
1300                                                 header->addr2);
1301                 /* fall through */
1302         default:
1303                         iwl_pass_packet_to_mac80211(priv, include_phy, rxb,
1304                                    &rx_status);
1305                 break;
1306
1307         }
1308 }
1309 EXPORT_SYMBOL(iwl_rx_reply_rx);
1310
1311 /* Cache phy data (Rx signal strength, etc) for HT frame (REPLY_RX_PHY_CMD).
1312  * This will be used later in iwl_rx_reply_rx() for REPLY_RX_MPDU_CMD. */
1313 void iwl_rx_reply_rx_phy(struct iwl_priv *priv,
1314                                     struct iwl_rx_mem_buffer *rxb)
1315 {
1316         struct iwl_rx_packet *pkt = (struct iwl_rx_packet *)rxb->skb->data;
1317         priv->last_phy_res[0] = 1;
1318         memcpy(&priv->last_phy_res[1], &(pkt->u.raw[0]),
1319                sizeof(struct iwl4965_rx_phy_res));
1320 }
1321 EXPORT_SYMBOL(iwl_rx_reply_rx_phy);