2 Copyright (C) 2004 - 2008 rt2x00 SourceForge Project
3 <http://rt2x00.serialmonkey.com>
5 This program is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published by
7 the Free Software Foundation; either version 2 of the License, or
8 (at your option) any later version.
10 This program is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 GNU General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with this program; if not, write to the
17 Free Software Foundation, Inc.,
18 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
23 Abstract: rt2x00 queue specific routines.
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/dma-mapping.h>
31 #include "rt2x00lib.h"
33 struct sk_buff *rt2x00queue_alloc_rxskb(struct rt2x00_dev *rt2x00dev,
34 struct queue_entry *entry)
37 struct skb_frame_desc *skbdesc;
38 unsigned int frame_size;
39 unsigned int head_size = 0;
40 unsigned int tail_size = 0;
43 * The frame size includes descriptor size, because the
44 * hardware directly receive the frame into the skbuffer.
46 frame_size = entry->queue->data_size + entry->queue->desc_size;
49 * The payload should be aligned to a 4-byte boundary,
50 * this means we need at least 3 bytes for moving the frame
51 * into the correct offset.
56 * For IV/EIV/ICV assembly we must make sure there is
57 * at least 8 bytes bytes available in headroom for IV/EIV
58 * and 8 bytes for ICV data as tailroon.
60 if (test_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags)) {
68 skb = dev_alloc_skb(frame_size + head_size + tail_size);
73 * Make sure we not have a frame with the requested bytes
74 * available in the head and tail.
76 skb_reserve(skb, head_size);
77 skb_put(skb, frame_size);
82 skbdesc = get_skb_frame_desc(skb);
83 memset(skbdesc, 0, sizeof(*skbdesc));
84 skbdesc->entry = entry;
86 if (test_bit(DRIVER_REQUIRE_DMA, &rt2x00dev->flags)) {
87 skbdesc->skb_dma = dma_map_single(rt2x00dev->dev,
91 skbdesc->flags |= SKBDESC_DMA_MAPPED_RX;
97 void rt2x00queue_map_txskb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
99 struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
102 * If device has requested headroom, we should make sure that
103 * is also mapped to the DMA so it can be used for transfering
104 * additional descriptor information to the hardware.
106 skb_push(skb, rt2x00dev->hw->extra_tx_headroom);
109 dma_map_single(rt2x00dev->dev, skb->data, skb->len, DMA_TO_DEVICE);
112 * Restore data pointer to original location again.
114 skb_pull(skb, rt2x00dev->hw->extra_tx_headroom);
116 skbdesc->flags |= SKBDESC_DMA_MAPPED_TX;
118 EXPORT_SYMBOL_GPL(rt2x00queue_map_txskb);
120 void rt2x00queue_unmap_skb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
122 struct skb_frame_desc *skbdesc = get_skb_frame_desc(skb);
124 if (skbdesc->flags & SKBDESC_DMA_MAPPED_RX) {
125 dma_unmap_single(rt2x00dev->dev, skbdesc->skb_dma, skb->len,
127 skbdesc->flags &= ~SKBDESC_DMA_MAPPED_RX;
130 if (skbdesc->flags & SKBDESC_DMA_MAPPED_TX) {
132 * Add headroom to the skb length, it has been removed
133 * by the driver, but it was actually mapped to DMA.
135 dma_unmap_single(rt2x00dev->dev, skbdesc->skb_dma,
136 skb->len + rt2x00dev->hw->extra_tx_headroom,
138 skbdesc->flags &= ~SKBDESC_DMA_MAPPED_TX;
142 void rt2x00queue_free_skb(struct rt2x00_dev *rt2x00dev, struct sk_buff *skb)
147 rt2x00queue_unmap_skb(rt2x00dev, skb);
148 dev_kfree_skb_any(skb);
151 static void rt2x00queue_create_tx_descriptor(struct queue_entry *entry,
152 struct txentry_desc *txdesc)
154 struct rt2x00_dev *rt2x00dev = entry->queue->rt2x00dev;
155 struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(entry->skb);
156 struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)entry->skb->data;
157 struct ieee80211_tx_rate *txrate = &tx_info->control.rates[0];
158 struct ieee80211_rate *rate =
159 ieee80211_get_tx_rate(rt2x00dev->hw, tx_info);
160 const struct rt2x00_rate *hwrate;
161 unsigned int data_length;
162 unsigned int duration;
163 unsigned int residual;
164 unsigned long irqflags;
166 memset(txdesc, 0, sizeof(*txdesc));
169 * Initialize information from queue
171 txdesc->queue = entry->queue->qid;
172 txdesc->cw_min = entry->queue->cw_min;
173 txdesc->cw_max = entry->queue->cw_max;
174 txdesc->aifs = entry->queue->aifs;
176 /* Data length + CRC */
177 data_length = entry->skb->len + 4;
180 * Check whether this frame is to be acked.
182 if (!(tx_info->flags & IEEE80211_TX_CTL_NO_ACK))
183 __set_bit(ENTRY_TXD_ACK, &txdesc->flags);
185 if (test_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags) &&
186 !entry->skb->do_not_encrypt) {
187 /* Apply crypto specific descriptor information */
188 rt2x00crypto_create_tx_descriptor(entry, txdesc);
191 * Extend frame length to include all encryption overhead
192 * that will be added by the hardware.
194 data_length += rt2x00crypto_tx_overhead(tx_info);
198 * Check if this is a RTS/CTS frame
200 if (ieee80211_is_rts(hdr->frame_control) ||
201 ieee80211_is_cts(hdr->frame_control)) {
202 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
203 if (ieee80211_is_rts(hdr->frame_control))
204 __set_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags);
206 __set_bit(ENTRY_TXD_CTS_FRAME, &txdesc->flags);
207 if (tx_info->control.rts_cts_rate_idx >= 0)
209 ieee80211_get_rts_cts_rate(rt2x00dev->hw, tx_info);
213 * Determine retry information.
215 txdesc->retry_limit = tx_info->control.rates[0].count - 1;
216 if (txdesc->retry_limit >= rt2x00dev->long_retry)
217 __set_bit(ENTRY_TXD_RETRY_MODE, &txdesc->flags);
220 * Check if more fragments are pending
222 if (ieee80211_has_morefrags(hdr->frame_control)) {
223 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
224 __set_bit(ENTRY_TXD_MORE_FRAG, &txdesc->flags);
228 * Beacons and probe responses require the tsf timestamp
229 * to be inserted into the frame.
231 if (ieee80211_is_beacon(hdr->frame_control) ||
232 ieee80211_is_probe_resp(hdr->frame_control))
233 __set_bit(ENTRY_TXD_REQ_TIMESTAMP, &txdesc->flags);
236 * Determine with what IFS priority this frame should be send.
237 * Set ifs to IFS_SIFS when the this is not the first fragment,
238 * or this fragment came after RTS/CTS.
240 if (test_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags)) {
241 txdesc->ifs = IFS_SIFS;
242 } else if (tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT) {
243 __set_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags);
244 txdesc->ifs = IFS_BACKOFF;
246 txdesc->ifs = IFS_SIFS;
250 * Hardware should insert sequence counter.
251 * FIXME: We insert a software sequence counter first for
252 * hardware that doesn't support hardware sequence counting.
254 * This is wrong because beacons are not getting sequence
255 * numbers assigned properly.
257 * A secondary problem exists for drivers that cannot toggle
258 * sequence counting per-frame, since those will override the
259 * sequence counter given by mac80211.
261 if (tx_info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
262 if (likely(tx_info->control.vif)) {
263 struct rt2x00_intf *intf;
265 intf = vif_to_intf(tx_info->control.vif);
267 spin_lock_irqsave(&intf->seqlock, irqflags);
269 if (test_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags))
271 hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
272 hdr->seq_ctrl |= cpu_to_le16(intf->seqno);
274 spin_unlock_irqrestore(&intf->seqlock, irqflags);
276 __set_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
282 * Length calculation depends on OFDM/CCK rate.
284 hwrate = rt2x00_get_rate(rate->hw_value);
285 txdesc->signal = hwrate->plcp;
286 txdesc->service = 0x04;
288 if (hwrate->flags & DEV_RATE_OFDM) {
289 __set_bit(ENTRY_TXD_OFDM_RATE, &txdesc->flags);
291 txdesc->length_high = (data_length >> 6) & 0x3f;
292 txdesc->length_low = data_length & 0x3f;
295 * Convert length to microseconds.
297 residual = GET_DURATION_RES(data_length, hwrate->bitrate);
298 duration = GET_DURATION(data_length, hwrate->bitrate);
304 * Check if we need to set the Length Extension
306 if (hwrate->bitrate == 110 && residual <= 30)
307 txdesc->service |= 0x80;
310 txdesc->length_high = (duration >> 8) & 0xff;
311 txdesc->length_low = duration & 0xff;
314 * When preamble is enabled we should set the
315 * preamble bit for the signal.
317 if (txrate->flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
318 txdesc->signal |= 0x08;
322 static void rt2x00queue_write_tx_descriptor(struct queue_entry *entry,
323 struct txentry_desc *txdesc)
325 struct data_queue *queue = entry->queue;
326 struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
328 rt2x00dev->ops->lib->write_tx_desc(rt2x00dev, entry->skb, txdesc);
331 * All processing on the frame has been completed, this means
332 * it is now ready to be dumped to userspace through debugfs.
334 rt2x00debug_dump_frame(rt2x00dev, DUMP_FRAME_TX, entry->skb);
337 * Check if we need to kick the queue, there are however a few rules
338 * 1) Don't kick beacon queue
339 * 2) Don't kick unless this is the last in frame in a burst.
340 * When the burst flag is set, this frame is always followed
341 * by another frame which in some way are related to eachother.
342 * This is true for fragments, RTS or CTS-to-self frames.
343 * 3) Rule 2 can be broken when the available entries
344 * in the queue are less then a certain threshold.
346 if (entry->queue->qid == QID_BEACON)
349 if (rt2x00queue_threshold(queue) ||
350 !test_bit(ENTRY_TXD_BURST, &txdesc->flags))
351 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, queue->qid);
354 int rt2x00queue_write_tx_frame(struct data_queue *queue, struct sk_buff *skb)
356 struct ieee80211_tx_info *tx_info;
357 struct queue_entry *entry = rt2x00queue_get_entry(queue, Q_INDEX);
358 struct txentry_desc txdesc;
359 struct skb_frame_desc *skbdesc;
360 unsigned int iv_len = 0;
361 u8 rate_idx, rate_flags;
363 if (unlikely(rt2x00queue_full(queue)))
366 if (test_and_set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags)) {
367 ERROR(queue->rt2x00dev,
368 "Arrived at non-free entry in the non-full queue %d.\n"
369 "Please file bug report to %s.\n",
370 queue->qid, DRV_PROJECT);
375 * Copy all TX descriptor information into txdesc,
376 * after that we are free to use the skb->cb array
377 * for our information.
380 rt2x00queue_create_tx_descriptor(entry, &txdesc);
382 if (IEEE80211_SKB_CB(skb)->control.hw_key != NULL)
383 iv_len = IEEE80211_SKB_CB(skb)->control.hw_key->iv_len;
386 * All information is retrieved from the skb->cb array,
387 * now we should claim ownership of the driver part of that
388 * array, preserving the bitrate index and flags.
390 tx_info = IEEE80211_SKB_CB(skb);
391 rate_idx = tx_info->control.rates[0].idx;
392 rate_flags = tx_info->control.rates[0].flags;
393 skbdesc = get_skb_frame_desc(skb);
394 memset(skbdesc, 0, sizeof(*skbdesc));
395 skbdesc->entry = entry;
396 skbdesc->tx_rate_idx = rate_idx;
397 skbdesc->tx_rate_flags = rate_flags;
400 * When hardware encryption is supported, and this frame
401 * is to be encrypted, we should strip the IV/EIV data from
402 * the frame so we can provide it to the driver seperately.
404 if (test_bit(ENTRY_TXD_ENCRYPT, &txdesc.flags) &&
405 !test_bit(ENTRY_TXD_ENCRYPT_IV, &txdesc.flags)) {
406 if (test_bit(CONFIG_CRYPTO_COPY_IV, &queue->rt2x00dev->flags))
407 rt2x00crypto_tx_copy_iv(skb, iv_len);
409 rt2x00crypto_tx_remove_iv(skb, iv_len);
413 * It could be possible that the queue was corrupted and this
414 * call failed. Since we always return NETDEV_TX_OK to mac80211,
415 * this frame will simply be dropped.
417 if (unlikely(queue->rt2x00dev->ops->lib->write_tx_data(entry))) {
418 clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
423 if (test_bit(DRIVER_REQUIRE_DMA, &queue->rt2x00dev->flags))
424 rt2x00queue_map_txskb(queue->rt2x00dev, skb);
426 set_bit(ENTRY_DATA_PENDING, &entry->flags);
428 rt2x00queue_index_inc(queue, Q_INDEX);
429 rt2x00queue_write_tx_descriptor(entry, &txdesc);
434 int rt2x00queue_update_beacon(struct rt2x00_dev *rt2x00dev,
435 struct ieee80211_vif *vif)
437 struct rt2x00_intf *intf = vif_to_intf(vif);
438 struct skb_frame_desc *skbdesc;
439 struct txentry_desc txdesc;
442 if (unlikely(!intf->beacon))
445 intf->beacon->skb = ieee80211_beacon_get(rt2x00dev->hw, vif);
446 if (!intf->beacon->skb)
450 * Copy all TX descriptor information into txdesc,
451 * after that we are free to use the skb->cb array
452 * for our information.
454 rt2x00queue_create_tx_descriptor(intf->beacon, &txdesc);
457 * For the descriptor we use a local array from where the
458 * driver can move it to the correct location required for
461 memset(desc, 0, sizeof(desc));
464 * Fill in skb descriptor
466 skbdesc = get_skb_frame_desc(intf->beacon->skb);
467 memset(skbdesc, 0, sizeof(*skbdesc));
468 skbdesc->desc = desc;
469 skbdesc->desc_len = intf->beacon->queue->desc_size;
470 skbdesc->entry = intf->beacon;
473 * Write TX descriptor into reserved room in front of the beacon.
475 rt2x00queue_write_tx_descriptor(intf->beacon, &txdesc);
478 * Send beacon to hardware.
479 * Also enable beacon generation, which might have been disabled
480 * by the driver during the config_beacon() callback function.
482 rt2x00dev->ops->lib->write_beacon(intf->beacon);
483 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, QID_BEACON);
488 struct data_queue *rt2x00queue_get_queue(struct rt2x00_dev *rt2x00dev,
489 const enum data_queue_qid queue)
491 int atim = test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
493 if (queue < rt2x00dev->ops->tx_queues && rt2x00dev->tx)
494 return &rt2x00dev->tx[queue];
499 if (queue == QID_BEACON)
500 return &rt2x00dev->bcn[0];
501 else if (queue == QID_ATIM && atim)
502 return &rt2x00dev->bcn[1];
506 EXPORT_SYMBOL_GPL(rt2x00queue_get_queue);
508 struct queue_entry *rt2x00queue_get_entry(struct data_queue *queue,
509 enum queue_index index)
511 struct queue_entry *entry;
512 unsigned long irqflags;
514 if (unlikely(index >= Q_INDEX_MAX)) {
515 ERROR(queue->rt2x00dev,
516 "Entry requested from invalid index type (%d)\n", index);
520 spin_lock_irqsave(&queue->lock, irqflags);
522 entry = &queue->entries[queue->index[index]];
524 spin_unlock_irqrestore(&queue->lock, irqflags);
528 EXPORT_SYMBOL_GPL(rt2x00queue_get_entry);
530 void rt2x00queue_index_inc(struct data_queue *queue, enum queue_index index)
532 unsigned long irqflags;
534 if (unlikely(index >= Q_INDEX_MAX)) {
535 ERROR(queue->rt2x00dev,
536 "Index change on invalid index type (%d)\n", index);
540 spin_lock_irqsave(&queue->lock, irqflags);
542 queue->index[index]++;
543 if (queue->index[index] >= queue->limit)
544 queue->index[index] = 0;
546 if (index == Q_INDEX) {
548 } else if (index == Q_INDEX_DONE) {
553 spin_unlock_irqrestore(&queue->lock, irqflags);
556 static void rt2x00queue_reset(struct data_queue *queue)
558 unsigned long irqflags;
560 spin_lock_irqsave(&queue->lock, irqflags);
564 memset(queue->index, 0, sizeof(queue->index));
566 spin_unlock_irqrestore(&queue->lock, irqflags);
569 void rt2x00queue_init_queues(struct rt2x00_dev *rt2x00dev)
571 struct data_queue *queue;
574 queue_for_each(rt2x00dev, queue) {
575 rt2x00queue_reset(queue);
577 for (i = 0; i < queue->limit; i++) {
578 queue->entries[i].flags = 0;
580 rt2x00dev->ops->lib->clear_entry(&queue->entries[i]);
585 static int rt2x00queue_alloc_entries(struct data_queue *queue,
586 const struct data_queue_desc *qdesc)
588 struct queue_entry *entries;
589 unsigned int entry_size;
592 rt2x00queue_reset(queue);
594 queue->limit = qdesc->entry_num;
595 queue->threshold = DIV_ROUND_UP(qdesc->entry_num, 10);
596 queue->data_size = qdesc->data_size;
597 queue->desc_size = qdesc->desc_size;
600 * Allocate all queue entries.
602 entry_size = sizeof(*entries) + qdesc->priv_size;
603 entries = kzalloc(queue->limit * entry_size, GFP_KERNEL);
607 #define QUEUE_ENTRY_PRIV_OFFSET(__base, __index, __limit, __esize, __psize) \
608 ( ((char *)(__base)) + ((__limit) * (__esize)) + \
609 ((__index) * (__psize)) )
611 for (i = 0; i < queue->limit; i++) {
612 entries[i].flags = 0;
613 entries[i].queue = queue;
614 entries[i].skb = NULL;
615 entries[i].entry_idx = i;
616 entries[i].priv_data =
617 QUEUE_ENTRY_PRIV_OFFSET(entries, i, queue->limit,
618 sizeof(*entries), qdesc->priv_size);
621 #undef QUEUE_ENTRY_PRIV_OFFSET
623 queue->entries = entries;
628 static void rt2x00queue_free_skbs(struct rt2x00_dev *rt2x00dev,
629 struct data_queue *queue)
636 for (i = 0; i < queue->limit; i++) {
637 if (queue->entries[i].skb)
638 rt2x00queue_free_skb(rt2x00dev, queue->entries[i].skb);
642 static int rt2x00queue_alloc_rxskbs(struct rt2x00_dev *rt2x00dev,
643 struct data_queue *queue)
648 for (i = 0; i < queue->limit; i++) {
649 skb = rt2x00queue_alloc_rxskb(rt2x00dev, &queue->entries[i]);
652 queue->entries[i].skb = skb;
658 int rt2x00queue_initialize(struct rt2x00_dev *rt2x00dev)
660 struct data_queue *queue;
663 status = rt2x00queue_alloc_entries(rt2x00dev->rx, rt2x00dev->ops->rx);
667 tx_queue_for_each(rt2x00dev, queue) {
668 status = rt2x00queue_alloc_entries(queue, rt2x00dev->ops->tx);
673 status = rt2x00queue_alloc_entries(rt2x00dev->bcn, rt2x00dev->ops->bcn);
677 if (test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags)) {
678 status = rt2x00queue_alloc_entries(&rt2x00dev->bcn[1],
679 rt2x00dev->ops->atim);
684 status = rt2x00queue_alloc_rxskbs(rt2x00dev, rt2x00dev->rx);
691 ERROR(rt2x00dev, "Queue entries allocation failed.\n");
693 rt2x00queue_uninitialize(rt2x00dev);
698 void rt2x00queue_uninitialize(struct rt2x00_dev *rt2x00dev)
700 struct data_queue *queue;
702 rt2x00queue_free_skbs(rt2x00dev, rt2x00dev->rx);
704 queue_for_each(rt2x00dev, queue) {
705 kfree(queue->entries);
706 queue->entries = NULL;
710 static void rt2x00queue_init(struct rt2x00_dev *rt2x00dev,
711 struct data_queue *queue, enum data_queue_qid qid)
713 spin_lock_init(&queue->lock);
715 queue->rt2x00dev = rt2x00dev;
723 int rt2x00queue_allocate(struct rt2x00_dev *rt2x00dev)
725 struct data_queue *queue;
726 enum data_queue_qid qid;
727 unsigned int req_atim =
728 !!test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
731 * We need the following queues:
735 * Atim: 1 (if required)
737 rt2x00dev->data_queues = 2 + rt2x00dev->ops->tx_queues + req_atim;
739 queue = kzalloc(rt2x00dev->data_queues * sizeof(*queue), GFP_KERNEL);
741 ERROR(rt2x00dev, "Queue allocation failed.\n");
746 * Initialize pointers
748 rt2x00dev->rx = queue;
749 rt2x00dev->tx = &queue[1];
750 rt2x00dev->bcn = &queue[1 + rt2x00dev->ops->tx_queues];
753 * Initialize queue parameters.
755 * TX: qid = QID_AC_BE + index
756 * TX: cw_min: 2^5 = 32.
757 * TX: cw_max: 2^10 = 1024.
758 * BCN: qid = QID_BEACON
759 * ATIM: qid = QID_ATIM
761 rt2x00queue_init(rt2x00dev, rt2x00dev->rx, QID_RX);
764 tx_queue_for_each(rt2x00dev, queue)
765 rt2x00queue_init(rt2x00dev, queue, qid++);
767 rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[0], QID_BEACON);
769 rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[1], QID_ATIM);
774 void rt2x00queue_free(struct rt2x00_dev *rt2x00dev)
776 kfree(rt2x00dev->rx);
777 rt2x00dev->rx = NULL;
778 rt2x00dev->tx = NULL;
779 rt2x00dev->bcn = NULL;