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 <linux/slab.h>
32 #include <net/mac80211.h>
33 #include <asm/unaligned.h>
34 #include "iwl-eeprom.h"
39 #include "iwl-calib.h"
40 #include "iwl-helpers.h"
41 /************************** RX-FUNCTIONS ****************************/
43 * Rx theory of operation
45 * Driver allocates a circular buffer of Receive Buffer Descriptors (RBDs),
46 * each of which point to Receive Buffers to be filled by the NIC. These get
47 * used not only for Rx frames, but for any command response or notification
48 * from the NIC. The driver and NIC manage the Rx buffers by means
49 * of indexes into the circular buffer.
52 * The host/firmware share two index registers for managing the Rx buffers.
54 * The READ index maps to the first position that the firmware may be writing
55 * to -- the driver can read up to (but not including) this position and get
57 * The READ index is managed by the firmware once the card is enabled.
59 * The WRITE index maps to the last position the driver has read from -- the
60 * position preceding WRITE is the last slot the firmware can place a packet.
62 * The queue is empty (no good data) if WRITE = READ - 1, and is full if
65 * During initialization, the host sets up the READ queue position to the first
66 * INDEX position, and WRITE to the last (READ - 1 wrapped)
68 * When the firmware places a packet in a buffer, it will advance the READ index
69 * and fire the RX interrupt. The driver can then query the READ index and
70 * process as many packets as possible, moving the WRITE index forward as it
71 * resets the Rx queue buffers with new memory.
73 * The management in the driver is as follows:
74 * + A list of pre-allocated SKBs is stored in iwl->rxq->rx_free. When
75 * iwl->rxq->free_count drops to or below RX_LOW_WATERMARK, work is scheduled
76 * to replenish the iwl->rxq->rx_free.
77 * + In iwl_rx_replenish (scheduled) if 'processed' != 'read' then the
78 * iwl->rxq is replenished and the READ INDEX is updated (updating the
79 * 'processed' and 'read' driver indexes as well)
80 * + A received packet is processed and handed to the kernel network stack,
81 * detached from the iwl->rxq. The driver 'processed' index is updated.
82 * + The Host/Firmware iwl->rxq is replenished at tasklet time from the rx_free
83 * list. If there are no allocated buffers in iwl->rxq->rx_free, the READ
84 * INDEX is not incremented and iwl->status(RX_STALLED) is set. If there
85 * were enough free buffers and RX_STALLED is set it is cleared.
90 * iwl_rx_queue_alloc() Allocates rx_free
91 * iwl_rx_replenish() Replenishes rx_free list from rx_used, and calls
92 * iwl_rx_queue_restock
93 * iwl_rx_queue_restock() Moves available buffers from rx_free into Rx
94 * queue, updates firmware pointers, and updates
95 * the WRITE index. If insufficient rx_free buffers
96 * are available, schedules iwl_rx_replenish
98 * -- enable interrupts --
99 * ISR - iwl_rx() Detach iwl_rx_mem_buffers from pool up to the
100 * READ INDEX, detaching the SKB from the pool.
101 * Moves the packet buffer from queue to rx_used.
102 * Calls iwl_rx_queue_restock to refill any empty
109 * iwl_rx_queue_space - Return number of free slots available in queue.
111 int iwl_rx_queue_space(const struct iwl_rx_queue *q)
113 int s = q->read - q->write;
116 /* keep some buffer to not confuse full and empty queue */
122 EXPORT_SYMBOL(iwl_rx_queue_space);
125 * iwl_rx_queue_update_write_ptr - Update the write pointer for the RX queue
127 void iwl_rx_queue_update_write_ptr(struct iwl_priv *priv, struct iwl_rx_queue *q)
130 u32 rx_wrt_ptr_reg = priv->hw_params.rx_wrt_ptr_reg;
133 spin_lock_irqsave(&q->lock, flags);
135 if (q->need_update == 0)
138 /* If power-saving is in use, make sure device is awake */
139 if (test_bit(STATUS_POWER_PMI, &priv->status)) {
140 reg = iwl_read32(priv, CSR_UCODE_DRV_GP1);
142 if (reg & CSR_UCODE_DRV_GP1_BIT_MAC_SLEEP) {
143 IWL_DEBUG_INFO(priv, "Rx queue requesting wakeup, GP1 = 0x%x\n",
145 iwl_set_bit(priv, CSR_GP_CNTRL,
146 CSR_GP_CNTRL_REG_FLAG_MAC_ACCESS_REQ);
150 q->write_actual = (q->write & ~0x7);
151 iwl_write_direct32(priv, rx_wrt_ptr_reg, q->write_actual);
153 /* Else device is assumed to be awake */
155 /* Device expects a multiple of 8 */
156 q->write_actual = (q->write & ~0x7);
157 iwl_write_direct32(priv, rx_wrt_ptr_reg, q->write_actual);
163 spin_unlock_irqrestore(&q->lock, flags);
165 EXPORT_SYMBOL(iwl_rx_queue_update_write_ptr);
167 int iwl_rx_queue_alloc(struct iwl_priv *priv)
169 struct iwl_rx_queue *rxq = &priv->rxq;
170 struct device *dev = &priv->pci_dev->dev;
173 spin_lock_init(&rxq->lock);
174 INIT_LIST_HEAD(&rxq->rx_free);
175 INIT_LIST_HEAD(&rxq->rx_used);
177 /* Alloc the circular buffer of Read Buffer Descriptors (RBDs) */
178 rxq->bd = dma_alloc_coherent(dev, 4 * RX_QUEUE_SIZE, &rxq->dma_addr,
183 rxq->rb_stts = dma_alloc_coherent(dev, sizeof(struct iwl_rb_status),
184 &rxq->rb_stts_dma, GFP_KERNEL);
188 /* Fill the rx_used queue with _all_ of the Rx buffers */
189 for (i = 0; i < RX_FREE_BUFFERS + RX_QUEUE_SIZE; i++)
190 list_add_tail(&rxq->pool[i].list, &rxq->rx_used);
192 /* Set us so that we have processed and used all buffers, but have
193 * not restocked the Rx queue with fresh buffers */
194 rxq->read = rxq->write = 0;
195 rxq->write_actual = 0;
197 rxq->need_update = 0;
201 dma_free_coherent(&priv->pci_dev->dev, 4 * RX_QUEUE_SIZE, rxq->bd,
206 EXPORT_SYMBOL(iwl_rx_queue_alloc);
208 void iwl_rx_missed_beacon_notif(struct iwl_priv *priv,
209 struct iwl_rx_mem_buffer *rxb)
212 struct iwl_rx_packet *pkt = rxb_addr(rxb);
213 struct iwl_missed_beacon_notif *missed_beacon;
215 missed_beacon = &pkt->u.missed_beacon;
216 if (le32_to_cpu(missed_beacon->consecutive_missed_beacons) >
217 priv->missed_beacon_threshold) {
218 IWL_DEBUG_CALIB(priv, "missed bcn cnsq %d totl %d rcd %d expctd %d\n",
219 le32_to_cpu(missed_beacon->consecutive_missed_beacons),
220 le32_to_cpu(missed_beacon->total_missed_becons),
221 le32_to_cpu(missed_beacon->num_recvd_beacons),
222 le32_to_cpu(missed_beacon->num_expected_beacons));
223 if (!test_bit(STATUS_SCANNING, &priv->status))
224 iwl_init_sensitivity(priv);
227 EXPORT_SYMBOL(iwl_rx_missed_beacon_notif);
229 void iwl_rx_spectrum_measure_notif(struct iwl_priv *priv,
230 struct iwl_rx_mem_buffer *rxb)
232 struct iwl_rx_packet *pkt = rxb_addr(rxb);
233 struct iwl_spectrum_notification *report = &(pkt->u.spectrum_notif);
235 if (!report->state) {
237 "Spectrum Measure Notification: Start\n");
241 memcpy(&priv->measure_report, report, sizeof(*report));
242 priv->measurement_status |= MEASUREMENT_READY;
244 EXPORT_SYMBOL(iwl_rx_spectrum_measure_notif);
248 /* Calculate noise level, based on measurements during network silence just
249 * before arriving beacon. This measurement can be done only if we know
250 * exactly when to expect beacons, therefore only when we're associated. */
251 static void iwl_rx_calc_noise(struct iwl_priv *priv)
253 struct statistics_rx_non_phy *rx_info
254 = &(priv->statistics.rx.general);
255 int num_active_rx = 0;
256 int total_silence = 0;
258 le32_to_cpu(rx_info->beacon_silence_rssi_a) & IN_BAND_FILTER;
260 le32_to_cpu(rx_info->beacon_silence_rssi_b) & IN_BAND_FILTER;
262 le32_to_cpu(rx_info->beacon_silence_rssi_c) & IN_BAND_FILTER;
266 total_silence += bcn_silence_a;
270 total_silence += bcn_silence_b;
274 total_silence += bcn_silence_c;
278 /* Average among active antennas */
280 last_rx_noise = (total_silence / num_active_rx) - 107;
282 last_rx_noise = IWL_NOISE_MEAS_NOT_AVAILABLE;
284 IWL_DEBUG_CALIB(priv, "inband silence a %u, b %u, c %u, dBm %d\n",
285 bcn_silence_a, bcn_silence_b, bcn_silence_c,
289 #ifdef CONFIG_IWLWIFI_DEBUG
291 * based on the assumption of all statistics counter are in DWORD
292 * FIXME: This function is for debugging, do not deal with
293 * the case of counters roll-over.
295 static void iwl_accumulative_statistics(struct iwl_priv *priv,
301 u32 *delta, *max_delta;
303 prev_stats = (__le32 *)&priv->statistics;
304 accum_stats = (u32 *)&priv->accum_statistics;
305 delta = (u32 *)&priv->delta_statistics;
306 max_delta = (u32 *)&priv->max_delta;
308 for (i = sizeof(__le32); i < sizeof(struct iwl_notif_statistics);
309 i += sizeof(__le32), stats++, prev_stats++, delta++,
310 max_delta++, accum_stats++) {
311 if (le32_to_cpu(*stats) > le32_to_cpu(*prev_stats)) {
312 *delta = (le32_to_cpu(*stats) -
313 le32_to_cpu(*prev_stats));
314 *accum_stats += *delta;
315 if (*delta > *max_delta)
320 /* reset accumulative statistics for "no-counter" type statistics */
321 priv->accum_statistics.general.temperature =
322 priv->statistics.general.temperature;
323 priv->accum_statistics.general.temperature_m =
324 priv->statistics.general.temperature_m;
325 priv->accum_statistics.general.ttl_timestamp =
326 priv->statistics.general.ttl_timestamp;
327 priv->accum_statistics.tx.tx_power.ant_a =
328 priv->statistics.tx.tx_power.ant_a;
329 priv->accum_statistics.tx.tx_power.ant_b =
330 priv->statistics.tx.tx_power.ant_b;
331 priv->accum_statistics.tx.tx_power.ant_c =
332 priv->statistics.tx.tx_power.ant_c;
336 #define REG_RECALIB_PERIOD (60)
339 * iwl_good_plcp_health - checks for plcp error.
341 * When the plcp error is exceeding the thresholds, reset the radio
342 * to improve the throughput.
344 bool iwl_good_plcp_health(struct iwl_priv *priv,
345 struct iwl_rx_packet *pkt)
348 int combined_plcp_delta;
349 unsigned int plcp_msec;
350 unsigned long plcp_received_jiffies;
353 * check for plcp_err and trigger radio reset if it exceeds
354 * the plcp error threshold plcp_delta.
356 plcp_received_jiffies = jiffies;
357 plcp_msec = jiffies_to_msecs((long) plcp_received_jiffies -
358 (long) priv->plcp_jiffies);
359 priv->plcp_jiffies = plcp_received_jiffies;
361 * check to make sure plcp_msec is not 0 to prevent division
365 combined_plcp_delta =
366 (le32_to_cpu(pkt->u.stats.rx.ofdm.plcp_err) -
367 le32_to_cpu(priv->statistics.rx.ofdm.plcp_err)) +
368 (le32_to_cpu(pkt->u.stats.rx.ofdm_ht.plcp_err) -
369 le32_to_cpu(priv->statistics.rx.ofdm_ht.plcp_err));
371 if ((combined_plcp_delta > 0) &&
372 ((combined_plcp_delta * 100) / plcp_msec) >
373 priv->cfg->plcp_delta_threshold) {
375 * if plcp_err exceed the threshold,
376 * the following data is printed in csv format:
377 * Text: plcp_err exceeded %d,
378 * Received ofdm.plcp_err,
379 * Current ofdm.plcp_err,
380 * Received ofdm_ht.plcp_err,
381 * Current ofdm_ht.plcp_err,
382 * combined_plcp_delta,
385 IWL_DEBUG_RADIO(priv, "plcp_err exceeded %u, "
386 "%u, %u, %u, %u, %d, %u mSecs\n",
387 priv->cfg->plcp_delta_threshold,
388 le32_to_cpu(pkt->u.stats.rx.ofdm.plcp_err),
389 le32_to_cpu(priv->statistics.rx.ofdm.plcp_err),
390 le32_to_cpu(pkt->u.stats.rx.ofdm_ht.plcp_err),
392 priv->statistics.rx.ofdm_ht.plcp_err),
393 combined_plcp_delta, plcp_msec);
399 EXPORT_SYMBOL(iwl_good_plcp_health);
401 void iwl_recover_from_statistics(struct iwl_priv *priv,
402 struct iwl_rx_packet *pkt)
404 if (test_bit(STATUS_EXIT_PENDING, &priv->status))
406 if (iwl_is_associated(priv)) {
407 if (priv->cfg->ops->lib->check_ack_health) {
408 if (!priv->cfg->ops->lib->check_ack_health(
411 * low ack count detected
414 IWL_ERR(priv, "low ack count detected, "
415 "restart firmware\n");
416 if (!iwl_force_reset(priv, IWL_FW_RESET))
420 if (priv->cfg->ops->lib->check_plcp_health) {
421 if (!priv->cfg->ops->lib->check_plcp_health(
424 * high plcp error detected
427 iwl_force_reset(priv, IWL_RF_RESET);
432 EXPORT_SYMBOL(iwl_recover_from_statistics);
434 void iwl_rx_statistics(struct iwl_priv *priv,
435 struct iwl_rx_mem_buffer *rxb)
438 struct iwl_rx_packet *pkt = rxb_addr(rxb);
441 IWL_DEBUG_RX(priv, "Statistics notification received (%d vs %d).\n",
442 (int)sizeof(priv->statistics),
443 le32_to_cpu(pkt->len_n_flags) & FH_RSCSR_FRAME_SIZE_MSK);
445 change = ((priv->statistics.general.temperature !=
446 pkt->u.stats.general.temperature) ||
447 ((priv->statistics.flag &
448 STATISTICS_REPLY_FLG_HT40_MODE_MSK) !=
449 (pkt->u.stats.flag & STATISTICS_REPLY_FLG_HT40_MODE_MSK)));
451 #ifdef CONFIG_IWLWIFI_DEBUG
452 iwl_accumulative_statistics(priv, (__le32 *)&pkt->u.stats);
454 iwl_recover_from_statistics(priv, pkt);
456 memcpy(&priv->statistics, &pkt->u.stats, sizeof(priv->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->accum_statistics, 0,
485 sizeof(struct iwl_notif_statistics));
486 memset(&priv->delta_statistics, 0,
487 sizeof(struct iwl_notif_statistics));
488 memset(&priv->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);