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_rate *rate =
158 ieee80211_get_tx_rate(rt2x00dev->hw, tx_info);
159 const struct rt2x00_rate *hwrate;
160 unsigned int data_length;
161 unsigned int duration;
162 unsigned int residual;
163 unsigned long irqflags;
165 memset(txdesc, 0, sizeof(*txdesc));
168 * Initialize information from queue
170 txdesc->queue = entry->queue->qid;
171 txdesc->cw_min = entry->queue->cw_min;
172 txdesc->cw_max = entry->queue->cw_max;
173 txdesc->aifs = entry->queue->aifs;
175 /* Data length + CRC */
176 data_length = entry->skb->len + 4;
179 * Check whether this frame is to be acked.
181 if (!(tx_info->flags & IEEE80211_TX_CTL_NO_ACK))
182 __set_bit(ENTRY_TXD_ACK, &txdesc->flags);
184 if (test_bit(CONFIG_SUPPORT_HW_CRYPTO, &rt2x00dev->flags) &&
185 !entry->skb->do_not_encrypt) {
186 /* Apply crypto specific descriptor information */
187 rt2x00crypto_create_tx_descriptor(entry, txdesc);
190 * Extend frame length to include all encryption overhead
191 * that will be added by the hardware.
193 data_length += rt2x00crypto_tx_overhead(tx_info);
197 * Check if this is a RTS/CTS frame
199 if (ieee80211_is_rts(hdr->frame_control) ||
200 ieee80211_is_cts(hdr->frame_control)) {
201 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
202 if (ieee80211_is_rts(hdr->frame_control))
203 __set_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags);
205 __set_bit(ENTRY_TXD_CTS_FRAME, &txdesc->flags);
206 if (tx_info->control.rts_cts_rate_idx >= 0)
208 ieee80211_get_rts_cts_rate(rt2x00dev->hw, tx_info);
212 * Determine retry information.
214 txdesc->retry_limit = tx_info->control.rates[0].count - 1;
215 if (txdesc->retry_limit >= rt2x00dev->long_retry)
216 __set_bit(ENTRY_TXD_RETRY_MODE, &txdesc->flags);
219 * Check if more fragments are pending
221 if (ieee80211_has_morefrags(hdr->frame_control)) {
222 __set_bit(ENTRY_TXD_BURST, &txdesc->flags);
223 __set_bit(ENTRY_TXD_MORE_FRAG, &txdesc->flags);
227 * Beacons and probe responses require the tsf timestamp
228 * to be inserted into the frame.
230 if (ieee80211_is_beacon(hdr->frame_control) ||
231 ieee80211_is_probe_resp(hdr->frame_control))
232 __set_bit(ENTRY_TXD_REQ_TIMESTAMP, &txdesc->flags);
235 * Determine with what IFS priority this frame should be send.
236 * Set ifs to IFS_SIFS when the this is not the first fragment,
237 * or this fragment came after RTS/CTS.
239 if (test_bit(ENTRY_TXD_RTS_FRAME, &txdesc->flags)) {
240 txdesc->ifs = IFS_SIFS;
241 } else if (tx_info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT) {
242 __set_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags);
243 txdesc->ifs = IFS_BACKOFF;
245 txdesc->ifs = IFS_SIFS;
249 * Hardware should insert sequence counter.
250 * FIXME: We insert a software sequence counter first for
251 * hardware that doesn't support hardware sequence counting.
253 * This is wrong because beacons are not getting sequence
254 * numbers assigned properly.
256 * A secondary problem exists for drivers that cannot toggle
257 * sequence counting per-frame, since those will override the
258 * sequence counter given by mac80211.
260 if (tx_info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ) {
261 if (likely(tx_info->control.vif)) {
262 struct rt2x00_intf *intf;
264 intf = vif_to_intf(tx_info->control.vif);
266 spin_lock_irqsave(&intf->seqlock, irqflags);
268 if (test_bit(ENTRY_TXD_FIRST_FRAGMENT, &txdesc->flags))
270 hdr->seq_ctrl &= cpu_to_le16(IEEE80211_SCTL_FRAG);
271 hdr->seq_ctrl |= cpu_to_le16(intf->seqno);
273 spin_unlock_irqrestore(&intf->seqlock, irqflags);
275 __set_bit(ENTRY_TXD_GENERATE_SEQ, &txdesc->flags);
281 * Length calculation depends on OFDM/CCK rate.
283 hwrate = rt2x00_get_rate(rate->hw_value);
284 txdesc->signal = hwrate->plcp;
285 txdesc->service = 0x04;
287 if (hwrate->flags & DEV_RATE_OFDM) {
288 __set_bit(ENTRY_TXD_OFDM_RATE, &txdesc->flags);
290 txdesc->length_high = (data_length >> 6) & 0x3f;
291 txdesc->length_low = data_length & 0x3f;
294 * Convert length to microseconds.
296 residual = GET_DURATION_RES(data_length, hwrate->bitrate);
297 duration = GET_DURATION(data_length, hwrate->bitrate);
303 * Check if we need to set the Length Extension
305 if (hwrate->bitrate == 110 && residual <= 30)
306 txdesc->service |= 0x80;
309 txdesc->length_high = (duration >> 8) & 0xff;
310 txdesc->length_low = duration & 0xff;
313 * When preamble is enabled we should set the
314 * preamble bit for the signal.
316 if (rt2x00_get_rate_preamble(rate->hw_value))
317 txdesc->signal |= 0x08;
321 static void rt2x00queue_write_tx_descriptor(struct queue_entry *entry,
322 struct txentry_desc *txdesc)
324 struct data_queue *queue = entry->queue;
325 struct rt2x00_dev *rt2x00dev = queue->rt2x00dev;
327 rt2x00dev->ops->lib->write_tx_desc(rt2x00dev, entry->skb, txdesc);
330 * All processing on the frame has been completed, this means
331 * it is now ready to be dumped to userspace through debugfs.
333 rt2x00debug_dump_frame(rt2x00dev, DUMP_FRAME_TX, entry->skb);
336 * Check if we need to kick the queue, there are however a few rules
337 * 1) Don't kick beacon queue
338 * 2) Don't kick unless this is the last in frame in a burst.
339 * When the burst flag is set, this frame is always followed
340 * by another frame which in some way are related to eachother.
341 * This is true for fragments, RTS or CTS-to-self frames.
342 * 3) Rule 2 can be broken when the available entries
343 * in the queue are less then a certain threshold.
345 if (entry->queue->qid == QID_BEACON)
348 if (rt2x00queue_threshold(queue) ||
349 !test_bit(ENTRY_TXD_BURST, &txdesc->flags))
350 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, queue->qid);
353 int rt2x00queue_write_tx_frame(struct data_queue *queue, struct sk_buff *skb)
355 struct ieee80211_tx_info *tx_info;
356 struct queue_entry *entry = rt2x00queue_get_entry(queue, Q_INDEX);
357 struct txentry_desc txdesc;
358 struct skb_frame_desc *skbdesc;
359 unsigned int iv_len = 0;
360 u8 rate_idx, rate_flags;
362 if (unlikely(rt2x00queue_full(queue)))
365 if (test_and_set_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags)) {
366 ERROR(queue->rt2x00dev,
367 "Arrived at non-free entry in the non-full queue %d.\n"
368 "Please file bug report to %s.\n",
369 queue->qid, DRV_PROJECT);
374 * Copy all TX descriptor information into txdesc,
375 * after that we are free to use the skb->cb array
376 * for our information.
379 rt2x00queue_create_tx_descriptor(entry, &txdesc);
381 if (IEEE80211_SKB_CB(skb)->control.hw_key != NULL)
382 iv_len = IEEE80211_SKB_CB(skb)->control.hw_key->iv_len;
385 * All information is retrieved from the skb->cb array,
386 * now we should claim ownership of the driver part of that
387 * array, preserving the bitrate index and flags.
389 tx_info = IEEE80211_SKB_CB(skb);
390 rate_idx = tx_info->control.rates[0].idx;
391 rate_flags = tx_info->control.rates[0].flags;
392 skbdesc = get_skb_frame_desc(skb);
393 memset(skbdesc, 0, sizeof(*skbdesc));
394 skbdesc->entry = entry;
395 skbdesc->tx_rate_idx = rate_idx;
396 skbdesc->tx_rate_flags = rate_flags;
399 * When hardware encryption is supported, and this frame
400 * is to be encrypted, we should strip the IV/EIV data from
401 * the frame so we can provide it to the driver seperately.
403 if (test_bit(ENTRY_TXD_ENCRYPT, &txdesc.flags) &&
404 !test_bit(ENTRY_TXD_ENCRYPT_IV, &txdesc.flags)) {
405 if (test_bit(CONFIG_CRYPTO_COPY_IV, &queue->rt2x00dev->flags))
406 rt2x00crypto_tx_copy_iv(skb, iv_len);
408 rt2x00crypto_tx_remove_iv(skb, iv_len);
412 * It could be possible that the queue was corrupted and this
413 * call failed. Since we always return NETDEV_TX_OK to mac80211,
414 * this frame will simply be dropped.
416 if (unlikely(queue->rt2x00dev->ops->lib->write_tx_data(entry))) {
417 clear_bit(ENTRY_OWNER_DEVICE_DATA, &entry->flags);
422 if (test_bit(DRIVER_REQUIRE_DMA, &queue->rt2x00dev->flags))
423 rt2x00queue_map_txskb(queue->rt2x00dev, skb);
425 set_bit(ENTRY_DATA_PENDING, &entry->flags);
427 rt2x00queue_index_inc(queue, Q_INDEX);
428 rt2x00queue_write_tx_descriptor(entry, &txdesc);
433 int rt2x00queue_update_beacon(struct rt2x00_dev *rt2x00dev,
434 struct ieee80211_vif *vif)
436 struct rt2x00_intf *intf = vif_to_intf(vif);
437 struct skb_frame_desc *skbdesc;
438 struct txentry_desc txdesc;
441 if (unlikely(!intf->beacon))
444 intf->beacon->skb = ieee80211_beacon_get(rt2x00dev->hw, vif);
445 if (!intf->beacon->skb)
449 * Copy all TX descriptor information into txdesc,
450 * after that we are free to use the skb->cb array
451 * for our information.
453 rt2x00queue_create_tx_descriptor(intf->beacon, &txdesc);
456 * For the descriptor we use a local array from where the
457 * driver can move it to the correct location required for
460 memset(desc, 0, sizeof(desc));
463 * Fill in skb descriptor
465 skbdesc = get_skb_frame_desc(intf->beacon->skb);
466 memset(skbdesc, 0, sizeof(*skbdesc));
467 skbdesc->desc = desc;
468 skbdesc->desc_len = intf->beacon->queue->desc_size;
469 skbdesc->entry = intf->beacon;
472 * Write TX descriptor into reserved room in front of the beacon.
474 rt2x00queue_write_tx_descriptor(intf->beacon, &txdesc);
477 * Send beacon to hardware.
478 * Also enable beacon generation, which might have been disabled
479 * by the driver during the config_beacon() callback function.
481 rt2x00dev->ops->lib->write_beacon(intf->beacon);
482 rt2x00dev->ops->lib->kick_tx_queue(rt2x00dev, QID_BEACON);
487 struct data_queue *rt2x00queue_get_queue(struct rt2x00_dev *rt2x00dev,
488 const enum data_queue_qid queue)
490 int atim = test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
492 if (queue < rt2x00dev->ops->tx_queues && rt2x00dev->tx)
493 return &rt2x00dev->tx[queue];
498 if (queue == QID_BEACON)
499 return &rt2x00dev->bcn[0];
500 else if (queue == QID_ATIM && atim)
501 return &rt2x00dev->bcn[1];
505 EXPORT_SYMBOL_GPL(rt2x00queue_get_queue);
507 struct queue_entry *rt2x00queue_get_entry(struct data_queue *queue,
508 enum queue_index index)
510 struct queue_entry *entry;
511 unsigned long irqflags;
513 if (unlikely(index >= Q_INDEX_MAX)) {
514 ERROR(queue->rt2x00dev,
515 "Entry requested from invalid index type (%d)\n", index);
519 spin_lock_irqsave(&queue->lock, irqflags);
521 entry = &queue->entries[queue->index[index]];
523 spin_unlock_irqrestore(&queue->lock, irqflags);
527 EXPORT_SYMBOL_GPL(rt2x00queue_get_entry);
529 void rt2x00queue_index_inc(struct data_queue *queue, enum queue_index index)
531 unsigned long irqflags;
533 if (unlikely(index >= Q_INDEX_MAX)) {
534 ERROR(queue->rt2x00dev,
535 "Index change on invalid index type (%d)\n", index);
539 spin_lock_irqsave(&queue->lock, irqflags);
541 queue->index[index]++;
542 if (queue->index[index] >= queue->limit)
543 queue->index[index] = 0;
545 if (index == Q_INDEX) {
547 } else if (index == Q_INDEX_DONE) {
552 spin_unlock_irqrestore(&queue->lock, irqflags);
555 static void rt2x00queue_reset(struct data_queue *queue)
557 unsigned long irqflags;
559 spin_lock_irqsave(&queue->lock, irqflags);
563 memset(queue->index, 0, sizeof(queue->index));
565 spin_unlock_irqrestore(&queue->lock, irqflags);
568 void rt2x00queue_init_queues(struct rt2x00_dev *rt2x00dev)
570 struct data_queue *queue;
573 queue_for_each(rt2x00dev, queue) {
574 rt2x00queue_reset(queue);
576 for (i = 0; i < queue->limit; i++) {
577 queue->entries[i].flags = 0;
579 rt2x00dev->ops->lib->clear_entry(&queue->entries[i]);
584 static int rt2x00queue_alloc_entries(struct data_queue *queue,
585 const struct data_queue_desc *qdesc)
587 struct queue_entry *entries;
588 unsigned int entry_size;
591 rt2x00queue_reset(queue);
593 queue->limit = qdesc->entry_num;
594 queue->threshold = DIV_ROUND_UP(qdesc->entry_num, 10);
595 queue->data_size = qdesc->data_size;
596 queue->desc_size = qdesc->desc_size;
599 * Allocate all queue entries.
601 entry_size = sizeof(*entries) + qdesc->priv_size;
602 entries = kzalloc(queue->limit * entry_size, GFP_KERNEL);
606 #define QUEUE_ENTRY_PRIV_OFFSET(__base, __index, __limit, __esize, __psize) \
607 ( ((char *)(__base)) + ((__limit) * (__esize)) + \
608 ((__index) * (__psize)) )
610 for (i = 0; i < queue->limit; i++) {
611 entries[i].flags = 0;
612 entries[i].queue = queue;
613 entries[i].skb = NULL;
614 entries[i].entry_idx = i;
615 entries[i].priv_data =
616 QUEUE_ENTRY_PRIV_OFFSET(entries, i, queue->limit,
617 sizeof(*entries), qdesc->priv_size);
620 #undef QUEUE_ENTRY_PRIV_OFFSET
622 queue->entries = entries;
627 static void rt2x00queue_free_skbs(struct rt2x00_dev *rt2x00dev,
628 struct data_queue *queue)
635 for (i = 0; i < queue->limit; i++) {
636 if (queue->entries[i].skb)
637 rt2x00queue_free_skb(rt2x00dev, queue->entries[i].skb);
641 static int rt2x00queue_alloc_rxskbs(struct rt2x00_dev *rt2x00dev,
642 struct data_queue *queue)
647 for (i = 0; i < queue->limit; i++) {
648 skb = rt2x00queue_alloc_rxskb(rt2x00dev, &queue->entries[i]);
651 queue->entries[i].skb = skb;
657 int rt2x00queue_initialize(struct rt2x00_dev *rt2x00dev)
659 struct data_queue *queue;
662 status = rt2x00queue_alloc_entries(rt2x00dev->rx, rt2x00dev->ops->rx);
666 tx_queue_for_each(rt2x00dev, queue) {
667 status = rt2x00queue_alloc_entries(queue, rt2x00dev->ops->tx);
672 status = rt2x00queue_alloc_entries(rt2x00dev->bcn, rt2x00dev->ops->bcn);
676 if (test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags)) {
677 status = rt2x00queue_alloc_entries(&rt2x00dev->bcn[1],
678 rt2x00dev->ops->atim);
683 status = rt2x00queue_alloc_rxskbs(rt2x00dev, rt2x00dev->rx);
690 ERROR(rt2x00dev, "Queue entries allocation failed.\n");
692 rt2x00queue_uninitialize(rt2x00dev);
697 void rt2x00queue_uninitialize(struct rt2x00_dev *rt2x00dev)
699 struct data_queue *queue;
701 rt2x00queue_free_skbs(rt2x00dev, rt2x00dev->rx);
703 queue_for_each(rt2x00dev, queue) {
704 kfree(queue->entries);
705 queue->entries = NULL;
709 static void rt2x00queue_init(struct rt2x00_dev *rt2x00dev,
710 struct data_queue *queue, enum data_queue_qid qid)
712 spin_lock_init(&queue->lock);
714 queue->rt2x00dev = rt2x00dev;
722 int rt2x00queue_allocate(struct rt2x00_dev *rt2x00dev)
724 struct data_queue *queue;
725 enum data_queue_qid qid;
726 unsigned int req_atim =
727 !!test_bit(DRIVER_REQUIRE_ATIM_QUEUE, &rt2x00dev->flags);
730 * We need the following queues:
734 * Atim: 1 (if required)
736 rt2x00dev->data_queues = 2 + rt2x00dev->ops->tx_queues + req_atim;
738 queue = kzalloc(rt2x00dev->data_queues * sizeof(*queue), GFP_KERNEL);
740 ERROR(rt2x00dev, "Queue allocation failed.\n");
745 * Initialize pointers
747 rt2x00dev->rx = queue;
748 rt2x00dev->tx = &queue[1];
749 rt2x00dev->bcn = &queue[1 + rt2x00dev->ops->tx_queues];
752 * Initialize queue parameters.
754 * TX: qid = QID_AC_BE + index
755 * TX: cw_min: 2^5 = 32.
756 * TX: cw_max: 2^10 = 1024.
757 * BCN: qid = QID_BEACON
758 * ATIM: qid = QID_ATIM
760 rt2x00queue_init(rt2x00dev, rt2x00dev->rx, QID_RX);
763 tx_queue_for_each(rt2x00dev, queue)
764 rt2x00queue_init(rt2x00dev, queue, qid++);
766 rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[0], QID_BEACON);
768 rt2x00queue_init(rt2x00dev, &rt2x00dev->bcn[1], QID_ATIM);
773 void rt2x00queue_free(struct rt2x00_dev *rt2x00dev)
775 kfree(rt2x00dev->rx);
776 rt2x00dev->rx = NULL;
777 rt2x00dev->tx = NULL;
778 rt2x00dev->bcn = NULL;