1 /******************************************************************************
3 * Copyright(c) 2003 - 2010 Intel Corporation. All rights reserved.
5 * Portions of this file are derived from the ipw3945 project, as well
6 * as portions of the ieee80211 subsystem header files.
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.
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
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
21 * The full GNU General Public License is included in this distribution in the
22 * file called LICENSE.
24 * Contact Information:
25 * Intel Linux Wireless <ilw@linux.intel.com>
26 * Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
28 *****************************************************************************/
30 #include <linux/etherdevice.h>
31 #include <net/mac80211.h>
32 #include <asm/unaligned.h>
33 #include "iwl-eeprom.h"
38 #include "iwl-calib.h"
39 #include "iwl-helpers.h"
40 /************************** RX-FUNCTIONS ****************************/
42 * Rx theory of operation
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.
51 * The host/firmware share two index registers for managing the Rx buffers.
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
56 * The READ index is managed by the firmware once the card is enabled.
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.
61 * The queue is empty (no good data) if WRITE = READ - 1, and is full if
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)
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.
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.
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
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
108 * iwl_rx_queue_space - Return number of free slots available in queue.
110 int iwl_rx_queue_space(const struct iwl_rx_queue *q)
112 int s = q->read - q->write;
115 /* keep some buffer to not confuse full and empty queue */
121 EXPORT_SYMBOL(iwl_rx_queue_space);
124 * iwl_rx_queue_update_write_ptr - Update the write pointer for the RX queue
126 void iwl_rx_queue_update_write_ptr(struct iwl_priv *priv, struct iwl_rx_queue *q)
129 u32 rx_wrt_ptr_reg = priv->hw_params.rx_wrt_ptr_reg;
132 spin_lock_irqsave(&q->lock, flags);
134 if (q->need_update == 0)
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);
141 if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
142 IWL_DEBUG_INFO(priv, "Rx queue requesting wakeup, GP1 = 0x%x\n",
144 iwl_set_bit(priv, CSR_GP_CNTRL,
145 CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
149 q->write_actual = (q->write & ~0x7);
150 iwl_write_direct32(priv, rx_wrt_ptr_reg, q->write_actual);
152 /* Else device is assumed to be awake */
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);
162 spin_unlock_irqrestore(&q->lock, flags);
164 EXPORT_SYMBOL(iwl_rx_queue_update_write_ptr);
166 int iwl_rx_queue_alloc(struct iwl_priv *priv)
168 struct iwl_rx_queue *rxq = &priv->rxq;
169 struct device *dev = &priv->pci_dev->dev;
172 spin_lock_init(&rxq->lock);
173 INIT_LIST_HEAD(&rxq->rx_free);
174 INIT_LIST_HEAD(&rxq->rx_used);
176 /* Alloc the circular buffer of Read Buffer Descriptors (RBDs) */
177 rxq->bd = dma_alloc_coherent(dev, 4 * RX_QUEUE_SIZE, &rxq->dma_addr,
182 rxq->rb_stts = dma_alloc_coherent(dev, sizeof(struct iwl_rb_status),
183 &rxq->rb_stts_dma, GFP_KERNEL);
187 /* Fill the rx_used queue with _all_ of the Rx buffers */
188 for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++)
189 list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
191 /* Set us so that we have processed and used all buffers, but have
192 * not restocked the Rx queue with fresh buffers */
193 rxq->read = rxq->write = 0;
194 rxq->write_actual = 0;
196 rxq->need_update = 0;
200 dma_free_coherent(&priv->pci_dev->dev, 4 * RX_QUEUE_SIZE, rxq->bd,
205 EXPORT_SYMBOL(iwl_rx_queue_alloc);
207 void iwl_rx_missed_beacon_notif(struct iwl_priv *priv,
208 struct iwl_rx_mem_buffer *rxb)
211 struct iwl_rx_packet *pkt = rxb_addr(rxb);
212 struct iwl_missed_beacon_notif *missed_beacon;
214 missed_beacon = &pkt->u.missed_beacon;
215 if (le32_to_cpu(missed_beacon->consecutive_missed_beacons) >
216 priv->missed_beacon_threshold) {
217 IWL_DEBUG_CALIB(priv, "missed bcn cnsq %d totl %d rcd %d expctd %d\n",
218 le32_to_cpu(missed_beacon->consecutive_missed_beacons),
219 le32_to_cpu(missed_beacon->total_missed_becons),
220 le32_to_cpu(missed_beacon->num_recvd_beacons),
221 le32_to_cpu(missed_beacon->num_expected_beacons));
222 if (!test_bit(STATUS_SCANNING, &priv->status))
223 iwl_init_sensitivity(priv);
226 EXPORT_SYMBOL(iwl_rx_missed_beacon_notif);
228 void iwl_rx_spectrum_measure_notif(struct iwl_priv *priv,
229 struct iwl_rx_mem_buffer *rxb)
231 struct iwl_rx_packet *pkt = rxb_addr(rxb);
232 struct iwl_spectrum_notification *report = &(pkt->u.spectrum_notif);
234 if (!report->state) {
236 "Spectrum Measure Notification: Start\n");
240 memcpy(&priv->measure_report, report, sizeof(*report));
241 priv->measurement_status |= MEASUREMENT_READY;
243 EXPORT_SYMBOL(iwl_rx_spectrum_measure_notif);
247 /* Calculate noise level, based on measurements during network silence just
248 * before arriving beacon. This measurement can be done only if we know
249 * exactly when to expect beacons, therefore only when we're associated. */
250 static void iwl_rx_calc_noise(struct iwl_priv *priv)
252 struct statistics_rx_non_phy *rx_info
253 = &(priv->_agn.statistics.rx.general);
254 int num_active_rx = 0;
255 int total_silence = 0;
257 le32_to_cpu(rx_info->beacon_silence_rssi_a) & IN_BAND_FILTER;
259 le32_to_cpu(rx_info->beacon_silence_rssi_b) & IN_BAND_FILTER;
261 le32_to_cpu(rx_info->beacon_silence_rssi_c) & IN_BAND_FILTER;
265 total_silence += bcn_silence_a;
269 total_silence += bcn_silence_b;
273 total_silence += bcn_silence_c;
277 /* Average among active antennas */
279 last_rx_noise = (total_silence / num_active_rx) - 107;
281 last_rx_noise = IWL_NOISE_MEAS_NOT_AVAILABLE;
283 IWL_DEBUG_CALIB(priv, "inband silence a %u, b %u, c %u, dBm %d\n",
284 bcn_silence_a, bcn_silence_b, bcn_silence_c,
288 #ifdef CONFIG_IWLWIFI_DEBUG
290 * based on the assumption of all statistics counter are in DWORD
291 * FIXME: This function is for debugging, do not deal with
292 * the case of counters roll-over.
294 static void iwl_accumulative_statistics(struct iwl_priv *priv,
300 u32 *delta, *max_delta;
302 prev_stats = (__le32 *)&priv->_agn.statistics;
303 accum_stats = (u32 *)&priv->_agn.accum_statistics;
304 delta = (u32 *)&priv->_agn.delta_statistics;
305 max_delta = (u32 *)&priv->_agn.max_delta;
307 for (i = sizeof(__le32); i < sizeof(struct iwl_notif_statistics);
308 i += sizeof(__le32), stats++, prev_stats++, delta++,
309 max_delta++, accum_stats++) {
310 if (le32_to_cpu(*stats) > le32_to_cpu(*prev_stats)) {
311 *delta = (le32_to_cpu(*stats) -
312 le32_to_cpu(*prev_stats));
313 *accum_stats += *delta;
314 if (*delta > *max_delta)
319 /* reset accumulative statistics for "no-counter" type statistics */
320 priv->_agn.accum_statistics.general.temperature =
321 priv->_agn.statistics.general.temperature;
322 priv->_agn.accum_statistics.general.temperature_m =
323 priv->_agn.statistics.general.temperature_m;
324 priv->_agn.accum_statistics.general.ttl_timestamp =
325 priv->_agn.statistics.general.ttl_timestamp;
326 priv->_agn.accum_statistics.tx.tx_power.ant_a =
327 priv->_agn.statistics.tx.tx_power.ant_a;
328 priv->_agn.accum_statistics.tx.tx_power.ant_b =
329 priv->_agn.statistics.tx.tx_power.ant_b;
330 priv->_agn.accum_statistics.tx.tx_power.ant_c =
331 priv->_agn.statistics.tx.tx_power.ant_c;
335 #define REG_RECALIB_PERIOD (60)
338 * iwl_good_plcp_health - checks for plcp error.
340 * When the plcp error is exceeding the thresholds, reset the radio
341 * to improve the throughput.
343 bool iwl_good_plcp_health(struct iwl_priv *priv,
344 struct iwl_rx_packet *pkt)
347 int combined_plcp_delta;
348 unsigned int plcp_msec;
349 unsigned long plcp_received_jiffies;
352 * check for plcp_err and trigger radio reset if it exceeds
353 * the plcp error threshold plcp_delta.
355 plcp_received_jiffies = jiffies;
356 plcp_msec = jiffies_to_msecs((long) plcp_received_jiffies -
357 (long) priv->plcp_jiffies);
358 priv->plcp_jiffies = plcp_received_jiffies;
360 * check to make sure plcp_msec is not 0 to prevent division
364 combined_plcp_delta =
365 (le32_to_cpu(pkt->u.stats.rx.ofdm.plcp_err) -
366 le32_to_cpu(priv->_agn.statistics.rx.ofdm.plcp_err)) +
367 (le32_to_cpu(pkt->u.stats.rx.ofdm_ht.plcp_err) -
368 le32_to_cpu(priv->_agn.statistics.rx.ofdm_ht.plcp_err));
370 if ((combined_plcp_delta > 0) &&
371 ((combined_plcp_delta * 100) / plcp_msec) >
372 priv->cfg->plcp_delta_threshold) {
374 * if plcp_err exceed the threshold,
375 * the following data is printed in csv format:
376 * Text: plcp_err exceeded %d,
377 * Received ofdm.plcp_err,
378 * Current ofdm.plcp_err,
379 * Received ofdm_ht.plcp_err,
380 * Current ofdm_ht.plcp_err,
381 * combined_plcp_delta,
384 IWL_DEBUG_RADIO(priv, "plcp_err exceeded %u, "
385 "%u, %u, %u, %u, %d, %u mSecs\n",
386 priv->cfg->plcp_delta_threshold,
387 le32_to_cpu(pkt->u.stats.rx.ofdm.plcp_err),
388 le32_to_cpu(priv->_agn.statistics.rx.ofdm.plcp_err),
389 le32_to_cpu(pkt->u.stats.rx.ofdm_ht.plcp_err),
391 priv->_agn.statistics.rx.ofdm_ht.plcp_err),
392 combined_plcp_delta, plcp_msec);
398 EXPORT_SYMBOL(iwl_good_plcp_health);
400 void iwl_recover_from_statistics(struct iwl_priv *priv,
401 struct iwl_rx_packet *pkt)
403 if (test_bit(STATUS_EXIT_PENDING, &priv->status))
405 if (iwl_is_associated(priv)) {
406 if (priv->cfg->ops->lib->check_ack_health) {
407 if (!priv->cfg->ops->lib->check_ack_health(
410 * low ack count detected
413 IWL_ERR(priv, "low ack count detected, "
414 "restart firmware\n");
415 if (!iwl_force_reset(priv, IWL_FW_RESET))
419 if (priv->cfg->ops->lib->check_plcp_health) {
420 if (!priv->cfg->ops->lib->check_plcp_health(
423 * high plcp error detected
426 iwl_force_reset(priv, IWL_RF_RESET);
431 EXPORT_SYMBOL(iwl_recover_from_statistics);
433 void iwl_rx_statistics(struct iwl_priv *priv,
434 struct iwl_rx_mem_buffer *rxb)
437 struct iwl_rx_packet *pkt = rxb_addr(rxb);
440 IWL_DEBUG_RX(priv, "Statistics notification received (%d vs %d).\n",
441 (int)sizeof(priv->_agn.statistics),
442 le32_to_cpu(pkt->len_n_flags) & FH_RSCSR_FRAME_SIZE_MSK);
444 change = ((priv->_agn.statistics.general.temperature !=
445 pkt->u.stats.general.temperature) ||
446 ((priv->_agn.statistics.flag &
447 STATISTICS_REPLY_FLG_HT40_MODE_MSK) !=
448 (pkt->u.stats.flag & STATISTICS_REPLY_FLG_HT40_MODE_MSK)));
450 #ifdef CONFIG_IWLWIFI_DEBUG
451 iwl_accumulative_statistics(priv, (__le32 *)&pkt->u.stats);
453 iwl_recover_from_statistics(priv, pkt);
455 memcpy(&priv->_agn.statistics, &pkt->u.stats,
456 sizeof(priv->_agn.statistics));
458 set_bit(STATUS_STATISTICS, &priv->status);
460 /* Reschedule the statistics timer to occur in
461 * REG_RECALIB_PERIOD seconds to ensure we get a
462 * thermal update even if the uCode doesn't give
464 mod_timer(&priv->statistics_periodic, jiffies +
465 msecs_to_jiffies(REG_RECALIB_PERIOD * 1000));
467 if (unlikely(!test_bit(STATUS_SCANNING, &priv->status)) &&
468 (pkt->hdr.cmd == STATISTICS_NOTIFICATION)) {
469 iwl_rx_calc_noise(priv);
470 queue_work(priv->workqueue, &priv->run_time_calib_work);
472 if (priv->cfg->ops->lib->temp_ops.temperature && change)
473 priv->cfg->ops->lib->temp_ops.temperature(priv);
475 EXPORT_SYMBOL(iwl_rx_statistics);
477 void iwl_reply_statistics(struct iwl_priv *priv,
478 struct iwl_rx_mem_buffer *rxb)
480 struct iwl_rx_packet *pkt = rxb_addr(rxb);
482 if (le32_to_cpu(pkt->u.stats.flag) & UCODE_STATISTICS_CLEAR_MSK) {
483 #ifdef CONFIG_IWLWIFI_DEBUG
484 memset(&priv->_agn.accum_statistics, 0,
485 sizeof(struct iwl_notif_statistics));
486 memset(&priv->_agn.delta_statistics, 0,
487 sizeof(struct iwl_notif_statistics));
488 memset(&priv->_agn.max_delta, 0,
489 sizeof(struct iwl_notif_statistics));
491 IWL_DEBUG_RX(priv, "Statistics have been cleared\n");
493 iwl_rx_statistics(priv, rxb);
495 EXPORT_SYMBOL(iwl_reply_statistics);
498 * returns non-zero if packet should be dropped
500 int iwl_set_decrypted_flag(struct iwl_priv *priv,
501 struct ieee80211_hdr *hdr,
503 struct ieee80211_rx_status *stats)
505 u16 fc = le16_to_cpu(hdr->frame_control);
507 if (priv->active_rxon.filter_flags & RXON_FILTER_DIS_DECRYPT_MSK)
510 if (!(fc & IEEE80211_FCTL_PROTECTED))
513 IWL_DEBUG_RX(priv, "decrypt_res:0x%x\n", decrypt_res);
514 switch (decrypt_res & RX_RES_STATUS_SEC_TYPE_MSK) {
515 case RX_RES_STATUS_SEC_TYPE_TKIP:
516 /* The uCode has got a bad phase 1 Key, pushes the packet.
517 * Decryption will be done in SW. */
518 if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
519 RX_RES_STATUS_BAD_KEY_TTAK)
522 case RX_RES_STATUS_SEC_TYPE_WEP:
523 if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
524 RX_RES_STATUS_BAD_ICV_MIC) {
525 /* bad ICV, the packet is destroyed since the
526 * decryption is inplace, drop it */
527 IWL_DEBUG_RX(priv, "Packet destroyed\n");
530 case RX_RES_STATUS_SEC_TYPE_CCMP:
531 if ((decrypt_res & RX_RES_STATUS_DECRYPT_TYPE_MSK) ==
532 RX_RES_STATUS_DECRYPT_OK) {
533 IWL_DEBUG_RX(priv, "hw decrypt successfully!!!\n");
534 stats->flag |= RX_FLAG_DECRYPTED;
543 EXPORT_SYMBOL(iwl_set_decrypted_flag);