Pull bugzilla-9429 into release branch
[pv_ops_mirror.git] / drivers / net / wireless / b43 / pio.c
blob67752a28eb9cc114468f3031b1ccb456d686dd3e
1 /*
3 Broadcom B43 wireless driver
5 PIO Transmission
7 Copyright (c) 2005 Michael Buesch <mb@bu3sch.de>
9 This program is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2 of the License, or
12 (at your option) any later version.
14 This program is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 GNU General Public License for more details.
19 You should have received a copy of the GNU General Public License
20 along with this program; see the file COPYING. If not, write to
21 the Free Software Foundation, Inc., 51 Franklin Steet, Fifth Floor,
22 Boston, MA 02110-1301, USA.
26 #include "b43.h"
27 #include "pio.h"
28 #include "main.h"
29 #include "xmit.h"
31 #include <linux/delay.h>
33 static void tx_start(struct b43_pioqueue *queue)
35 b43_pio_write(queue, B43_PIO_TXCTL, B43_PIO_TXCTL_INIT);
38 static void tx_octet(struct b43_pioqueue *queue, u8 octet)
40 if (queue->need_workarounds) {
41 b43_pio_write(queue, B43_PIO_TXDATA, octet);
42 b43_pio_write(queue, B43_PIO_TXCTL, B43_PIO_TXCTL_WRITELO);
43 } else {
44 b43_pio_write(queue, B43_PIO_TXCTL, B43_PIO_TXCTL_WRITELO);
45 b43_pio_write(queue, B43_PIO_TXDATA, octet);
49 static u16 tx_get_next_word(const u8 * txhdr,
50 const u8 * packet,
51 size_t txhdr_size, unsigned int *pos)
53 const u8 *source;
54 unsigned int i = *pos;
55 u16 ret;
57 if (i < txhdr_size) {
58 source = txhdr;
59 } else {
60 source = packet;
61 i -= txhdr_size;
63 ret = le16_to_cpu(*((__le16 *)(source + i)));
64 *pos += 2;
66 return ret;
69 static void tx_data(struct b43_pioqueue *queue,
70 u8 * txhdr, const u8 * packet, unsigned int octets)
72 u16 data;
73 unsigned int i = 0;
75 if (queue->need_workarounds) {
76 data = tx_get_next_word(txhdr, packet,
77 sizeof(struct b43_txhdr_fw4), &i);
78 b43_pio_write(queue, B43_PIO_TXDATA, data);
80 b43_pio_write(queue, B43_PIO_TXCTL,
81 B43_PIO_TXCTL_WRITELO | B43_PIO_TXCTL_WRITEHI);
82 while (i < octets - 1) {
83 data = tx_get_next_word(txhdr, packet,
84 sizeof(struct b43_txhdr_fw4), &i);
85 b43_pio_write(queue, B43_PIO_TXDATA, data);
87 if (octets % 2)
88 tx_octet(queue,
89 packet[octets - sizeof(struct b43_txhdr_fw4) - 1]);
92 static void tx_complete(struct b43_pioqueue *queue, struct sk_buff *skb)
94 if (queue->need_workarounds) {
95 b43_pio_write(queue, B43_PIO_TXDATA, skb->data[skb->len - 1]);
96 b43_pio_write(queue, B43_PIO_TXCTL,
97 B43_PIO_TXCTL_WRITELO | B43_PIO_TXCTL_COMPLETE);
98 } else {
99 b43_pio_write(queue, B43_PIO_TXCTL, B43_PIO_TXCTL_COMPLETE);
103 static u16 generate_cookie(struct b43_pioqueue *queue,
104 struct b43_pio_txpacket *packet)
106 u16 cookie = 0x0000;
107 u16 packetindex;
109 /* We use the upper 4 bits for the PIO
110 * controller ID and the lower 12 bits
111 * for the packet index (in the cache).
113 switch (queue->mmio_base) {
114 case B43_MMIO_PIO1_BASE:
115 break;
116 case B43_MMIO_PIO2_BASE:
117 cookie = 0x1000;
118 break;
119 case B43_MMIO_PIO3_BASE:
120 cookie = 0x2000;
121 break;
122 case B43_MMIO_PIO4_BASE:
123 cookie = 0x3000;
124 break;
125 default:
126 B43_WARN_ON(1);
128 packetindex = packet->index;
129 B43_WARN_ON(packetindex & ~0x0FFF);
130 cookie |= (u16) packetindex;
132 return cookie;
135 static
136 struct b43_pioqueue *parse_cookie(struct b43_wldev *dev,
137 u16 cookie, struct b43_pio_txpacket **packet)
139 struct b43_pio *pio = &dev->pio;
140 struct b43_pioqueue *queue = NULL;
141 int packetindex;
143 switch (cookie & 0xF000) {
144 case 0x0000:
145 queue = pio->queue0;
146 break;
147 case 0x1000:
148 queue = pio->queue1;
149 break;
150 case 0x2000:
151 queue = pio->queue2;
152 break;
153 case 0x3000:
154 queue = pio->queue3;
155 break;
156 default:
157 B43_WARN_ON(1);
159 packetindex = (cookie & 0x0FFF);
160 B43_WARN_ON(!(packetindex >= 0 && packetindex < B43_PIO_MAXTXPACKETS));
161 *packet = &(queue->tx_packets_cache[packetindex]);
163 return queue;
166 union txhdr_union {
167 struct b43_txhdr_fw4 txhdr_fw4;
170 static void pio_tx_write_fragment(struct b43_pioqueue *queue,
171 struct sk_buff *skb,
172 struct b43_pio_txpacket *packet,
173 size_t txhdr_size)
175 union txhdr_union txhdr_data;
176 u8 *txhdr = NULL;
177 unsigned int octets;
179 txhdr = (u8 *) (&txhdr_data.txhdr_fw4);
181 B43_WARN_ON(skb_shinfo(skb)->nr_frags);
182 b43_generate_txhdr(queue->dev,
183 txhdr, skb->data, skb->len,
184 &packet->txstat.control,
185 generate_cookie(queue, packet));
187 tx_start(queue);
188 octets = skb->len + txhdr_size;
189 if (queue->need_workarounds)
190 octets--;
191 tx_data(queue, txhdr, (u8 *) skb->data, octets);
192 tx_complete(queue, skb);
195 static void free_txpacket(struct b43_pio_txpacket *packet)
197 struct b43_pioqueue *queue = packet->queue;
199 if (packet->skb)
200 dev_kfree_skb_any(packet->skb);
201 list_move(&packet->list, &queue->txfree);
202 queue->nr_txfree++;
205 static int pio_tx_packet(struct b43_pio_txpacket *packet)
207 struct b43_pioqueue *queue = packet->queue;
208 struct sk_buff *skb = packet->skb;
209 u16 octets;
211 octets = (u16) skb->len + sizeof(struct b43_txhdr_fw4);
212 if (queue->tx_devq_size < octets) {
213 b43warn(queue->dev->wl, "PIO queue too small. "
214 "Dropping packet.\n");
215 /* Drop it silently (return success) */
216 free_txpacket(packet);
217 return 0;
219 B43_WARN_ON(queue->tx_devq_packets > B43_PIO_MAXTXDEVQPACKETS);
220 B43_WARN_ON(queue->tx_devq_used > queue->tx_devq_size);
221 /* Check if there is sufficient free space on the device
222 * TX queue. If not, return and let the TX tasklet
223 * retry later.
225 if (queue->tx_devq_packets == B43_PIO_MAXTXDEVQPACKETS)
226 return -EBUSY;
227 if (queue->tx_devq_used + octets > queue->tx_devq_size)
228 return -EBUSY;
229 /* Now poke the device. */
230 pio_tx_write_fragment(queue, skb, packet, sizeof(struct b43_txhdr_fw4));
232 /* Account for the packet size.
233 * (We must not overflow the device TX queue)
235 queue->tx_devq_packets++;
236 queue->tx_devq_used += octets;
238 /* Transmission started, everything ok, move the
239 * packet to the txrunning list.
241 list_move_tail(&packet->list, &queue->txrunning);
243 return 0;
246 static void tx_tasklet(unsigned long d)
248 struct b43_pioqueue *queue = (struct b43_pioqueue *)d;
249 struct b43_wldev *dev = queue->dev;
250 unsigned long flags;
251 struct b43_pio_txpacket *packet, *tmp_packet;
252 int err;
253 u16 txctl;
255 spin_lock_irqsave(&dev->wl->irq_lock, flags);
256 if (queue->tx_frozen)
257 goto out_unlock;
258 txctl = b43_pio_read(queue, B43_PIO_TXCTL);
259 if (txctl & B43_PIO_TXCTL_SUSPEND)
260 goto out_unlock;
262 list_for_each_entry_safe(packet, tmp_packet, &queue->txqueue, list) {
263 /* Try to transmit the packet. This can fail, if
264 * the device queue is full. In case of failure, the
265 * packet is left in the txqueue.
266 * If transmission succeed, the packet is moved to txrunning.
267 * If it is impossible to transmit the packet, it
268 * is dropped.
270 err = pio_tx_packet(packet);
271 if (err)
272 break;
274 out_unlock:
275 spin_unlock_irqrestore(&dev->wl->irq_lock, flags);
278 static void setup_txqueues(struct b43_pioqueue *queue)
280 struct b43_pio_txpacket *packet;
281 int i;
283 queue->nr_txfree = B43_PIO_MAXTXPACKETS;
284 for (i = 0; i < B43_PIO_MAXTXPACKETS; i++) {
285 packet = &(queue->tx_packets_cache[i]);
287 packet->queue = queue;
288 INIT_LIST_HEAD(&packet->list);
289 packet->index = i;
291 list_add(&packet->list, &queue->txfree);
295 static
296 struct b43_pioqueue *b43_setup_pioqueue(struct b43_wldev *dev,
297 u16 pio_mmio_base)
299 struct b43_pioqueue *queue;
300 u16 qsize;
302 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
303 if (!queue)
304 goto out;
306 queue->dev = dev;
307 queue->mmio_base = pio_mmio_base;
308 queue->need_workarounds = (dev->dev->id.revision < 3);
310 INIT_LIST_HEAD(&queue->txfree);
311 INIT_LIST_HEAD(&queue->txqueue);
312 INIT_LIST_HEAD(&queue->txrunning);
313 tasklet_init(&queue->txtask, tx_tasklet, (unsigned long)queue);
315 b43_write32(dev, B43_MMIO_MACCTL, b43_read32(dev, B43_MMIO_MACCTL)
316 & ~B43_MACCTL_BE);
318 qsize = b43_read16(dev, queue->mmio_base + B43_PIO_TXQBUFSIZE);
319 if (qsize == 0) {
320 b43err(dev->wl, "This card does not support PIO "
321 "operation mode. Please use DMA mode "
322 "(module parameter pio=0).\n");
323 goto err_freequeue;
325 if (qsize <= B43_PIO_TXQADJUST) {
326 b43err(dev->wl, "PIO tx device-queue too small (%u)\n", qsize);
327 goto err_freequeue;
329 qsize -= B43_PIO_TXQADJUST;
330 queue->tx_devq_size = qsize;
332 setup_txqueues(queue);
334 out:
335 return queue;
337 err_freequeue:
338 kfree(queue);
339 queue = NULL;
340 goto out;
343 static void cancel_transfers(struct b43_pioqueue *queue)
345 struct b43_pio_txpacket *packet, *tmp_packet;
347 tasklet_disable(&queue->txtask);
349 list_for_each_entry_safe(packet, tmp_packet, &queue->txrunning, list)
350 free_txpacket(packet);
351 list_for_each_entry_safe(packet, tmp_packet, &queue->txqueue, list)
352 free_txpacket(packet);
355 static void b43_destroy_pioqueue(struct b43_pioqueue *queue)
357 if (!queue)
358 return;
360 cancel_transfers(queue);
361 kfree(queue);
364 void b43_pio_free(struct b43_wldev *dev)
366 struct b43_pio *pio;
368 if (!b43_using_pio(dev))
369 return;
370 pio = &dev->pio;
372 b43_destroy_pioqueue(pio->queue3);
373 pio->queue3 = NULL;
374 b43_destroy_pioqueue(pio->queue2);
375 pio->queue2 = NULL;
376 b43_destroy_pioqueue(pio->queue1);
377 pio->queue1 = NULL;
378 b43_destroy_pioqueue(pio->queue0);
379 pio->queue0 = NULL;
382 int b43_pio_init(struct b43_wldev *dev)
384 struct b43_pio *pio = &dev->pio;
385 struct b43_pioqueue *queue;
386 int err = -ENOMEM;
388 queue = b43_setup_pioqueue(dev, B43_MMIO_PIO1_BASE);
389 if (!queue)
390 goto out;
391 pio->queue0 = queue;
393 queue = b43_setup_pioqueue(dev, B43_MMIO_PIO2_BASE);
394 if (!queue)
395 goto err_destroy0;
396 pio->queue1 = queue;
398 queue = b43_setup_pioqueue(dev, B43_MMIO_PIO3_BASE);
399 if (!queue)
400 goto err_destroy1;
401 pio->queue2 = queue;
403 queue = b43_setup_pioqueue(dev, B43_MMIO_PIO4_BASE);
404 if (!queue)
405 goto err_destroy2;
406 pio->queue3 = queue;
408 if (dev->dev->id.revision < 3)
409 dev->irq_savedstate |= B43_IRQ_PIO_WORKAROUND;
411 b43dbg(dev->wl, "PIO initialized\n");
412 err = 0;
413 out:
414 return err;
416 err_destroy2:
417 b43_destroy_pioqueue(pio->queue2);
418 pio->queue2 = NULL;
419 err_destroy1:
420 b43_destroy_pioqueue(pio->queue1);
421 pio->queue1 = NULL;
422 err_destroy0:
423 b43_destroy_pioqueue(pio->queue0);
424 pio->queue0 = NULL;
425 goto out;
428 int b43_pio_tx(struct b43_wldev *dev,
429 struct sk_buff *skb, struct ieee80211_tx_control *ctl)
431 struct b43_pioqueue *queue = dev->pio.queue1;
432 struct b43_pio_txpacket *packet;
434 B43_WARN_ON(queue->tx_suspended);
435 B43_WARN_ON(list_empty(&queue->txfree));
437 packet = list_entry(queue->txfree.next, struct b43_pio_txpacket, list);
438 packet->skb = skb;
440 memset(&packet->txstat, 0, sizeof(packet->txstat));
441 memcpy(&packet->txstat.control, ctl, sizeof(*ctl));
443 list_move_tail(&packet->list, &queue->txqueue);
444 queue->nr_txfree--;
445 queue->nr_tx_packets++;
446 B43_WARN_ON(queue->nr_txfree >= B43_PIO_MAXTXPACKETS);
448 tasklet_schedule(&queue->txtask);
450 return 0;
453 void b43_pio_handle_txstatus(struct b43_wldev *dev,
454 const struct b43_txstatus *status)
456 struct b43_pioqueue *queue;
457 struct b43_pio_txpacket *packet;
459 queue = parse_cookie(dev, status->cookie, &packet);
460 if (B43_WARN_ON(!queue))
461 return;
463 queue->tx_devq_packets--;
464 queue->tx_devq_used -=
465 (packet->skb->len + sizeof(struct b43_txhdr_fw4));
467 if (status->acked) {
468 packet->txstat.flags |= IEEE80211_TX_STATUS_ACK;
469 } else {
470 if (!(packet->txstat.control.flags & IEEE80211_TXCTL_NO_ACK))
471 packet->txstat.excessive_retries = 1;
473 if (status->frame_count == 0) {
474 /* The frame was not transmitted at all. */
475 packet->txstat.retry_count = 0;
476 } else
477 packet->txstat.retry_count = status->frame_count - 1;
478 ieee80211_tx_status_irqsafe(dev->wl->hw, packet->skb,
479 &(packet->txstat));
480 packet->skb = NULL;
482 free_txpacket(packet);
483 /* If there are packets on the txqueue, poke the tasklet
484 * to transmit them.
486 if (!list_empty(&queue->txqueue))
487 tasklet_schedule(&queue->txtask);
490 void b43_pio_get_tx_stats(struct b43_wldev *dev,
491 struct ieee80211_tx_queue_stats *stats)
493 struct b43_pio *pio = &dev->pio;
494 struct b43_pioqueue *queue;
495 struct ieee80211_tx_queue_stats_data *data;
497 queue = pio->queue1;
498 data = &(stats->data[0]);
499 data->len = B43_PIO_MAXTXPACKETS - queue->nr_txfree;
500 data->limit = B43_PIO_MAXTXPACKETS;
501 data->count = queue->nr_tx_packets;
504 static void pio_rx_error(struct b43_pioqueue *queue,
505 int clear_buffers, const char *error)
507 int i;
509 b43err(queue->dev->wl, "PIO RX error: %s\n", error);
510 b43_pio_write(queue, B43_PIO_RXCTL, B43_PIO_RXCTL_READY);
511 if (clear_buffers) {
512 B43_WARN_ON(queue->mmio_base != B43_MMIO_PIO1_BASE);
513 for (i = 0; i < 15; i++) {
514 /* Dummy read. */
515 b43_pio_read(queue, B43_PIO_RXDATA);
520 void b43_pio_rx(struct b43_pioqueue *queue)
522 __le16 preamble[21] = { 0 };
523 struct b43_rxhdr_fw4 *rxhdr;
524 u16 tmp, len;
525 u32 macstat;
526 int i, preamble_readwords;
527 struct sk_buff *skb;
529 tmp = b43_pio_read(queue, B43_PIO_RXCTL);
530 if (!(tmp & B43_PIO_RXCTL_DATAAVAILABLE))
531 return;
532 b43_pio_write(queue, B43_PIO_RXCTL, B43_PIO_RXCTL_DATAAVAILABLE);
534 for (i = 0; i < 10; i++) {
535 tmp = b43_pio_read(queue, B43_PIO_RXCTL);
536 if (tmp & B43_PIO_RXCTL_READY)
537 goto data_ready;
538 udelay(10);
540 b43dbg(queue->dev->wl, "PIO RX timed out\n");
541 return;
542 data_ready:
544 len = b43_pio_read(queue, B43_PIO_RXDATA);
545 if (unlikely(len > 0x700)) {
546 pio_rx_error(queue, 0, "len > 0x700");
547 return;
549 if (unlikely(len == 0 && queue->mmio_base != B43_MMIO_PIO4_BASE)) {
550 pio_rx_error(queue, 0, "len == 0");
551 return;
553 preamble[0] = cpu_to_le16(len);
554 if (queue->mmio_base == B43_MMIO_PIO4_BASE)
555 preamble_readwords = 14 / sizeof(u16);
556 else
557 preamble_readwords = 18 / sizeof(u16);
558 for (i = 0; i < preamble_readwords; i++) {
559 tmp = b43_pio_read(queue, B43_PIO_RXDATA);
560 preamble[i + 1] = cpu_to_le16(tmp);
562 rxhdr = (struct b43_rxhdr_fw4 *)preamble;
563 macstat = le32_to_cpu(rxhdr->mac_status);
564 if (macstat & B43_RX_MAC_FCSERR) {
565 pio_rx_error(queue,
566 (queue->mmio_base == B43_MMIO_PIO1_BASE),
567 "Frame FCS error");
568 return;
570 if (queue->mmio_base == B43_MMIO_PIO4_BASE) {
571 /* We received an xmit status. */
572 struct b43_hwtxstatus *hw;
574 hw = (struct b43_hwtxstatus *)(preamble + 1);
575 b43_handle_hwtxstatus(queue->dev, hw);
577 return;
580 skb = dev_alloc_skb(len);
581 if (unlikely(!skb)) {
582 pio_rx_error(queue, 1, "OOM");
583 return;
585 skb_put(skb, len);
586 for (i = 0; i < len - 1; i += 2) {
587 tmp = b43_pio_read(queue, B43_PIO_RXDATA);
588 *((__le16 *)(skb->data + i)) = cpu_to_le16(tmp);
590 if (len % 2) {
591 tmp = b43_pio_read(queue, B43_PIO_RXDATA);
592 skb->data[len - 1] = (tmp & 0x00FF);
593 /* The specs say the following is required, but
594 * it is wrong and corrupts the PLCP. If we don't do
595 * this, the PLCP seems to be correct. So ifdef it out for now.
597 #if 0
598 if (rxflags2 & B43_RXHDR_FLAGS2_TYPE2FRAME)
599 skb->data[2] = (tmp & 0xFF00) >> 8;
600 else
601 skb->data[0] = (tmp & 0xFF00) >> 8;
602 #endif
604 b43_rx(queue->dev, skb, rxhdr);
607 void b43_pio_tx_suspend(struct b43_pioqueue *queue)
609 b43_power_saving_ctl_bits(queue->dev, B43_PS_AWAKE);
610 b43_pio_write(queue, B43_PIO_TXCTL, b43_pio_read(queue, B43_PIO_TXCTL)
611 | B43_PIO_TXCTL_SUSPEND);
614 void b43_pio_tx_resume(struct b43_pioqueue *queue)
616 b43_pio_write(queue, B43_PIO_TXCTL, b43_pio_read(queue, B43_PIO_TXCTL)
617 & ~B43_PIO_TXCTL_SUSPEND);
618 b43_power_saving_ctl_bits(queue->dev, 0);
619 tasklet_schedule(&queue->txtask);
622 void b43_pio_freeze_txqueues(struct b43_wldev *dev)
624 struct b43_pio *pio;
626 B43_WARN_ON(!b43_using_pio(dev));
627 pio = &dev->pio;
628 pio->queue0->tx_frozen = 1;
629 pio->queue1->tx_frozen = 1;
630 pio->queue2->tx_frozen = 1;
631 pio->queue3->tx_frozen = 1;
634 void b43_pio_thaw_txqueues(struct b43_wldev *dev)
636 struct b43_pio *pio;
638 B43_WARN_ON(!b43_using_pio(dev));
639 pio = &dev->pio;
640 pio->queue0->tx_frozen = 0;
641 pio->queue1->tx_frozen = 0;
642 pio->queue2->tx_frozen = 0;
643 pio->queue3->tx_frozen = 0;
644 if (!list_empty(&pio->queue0->txqueue))
645 tasklet_schedule(&pio->queue0->txtask);
646 if (!list_empty(&pio->queue1->txqueue))
647 tasklet_schedule(&pio->queue1->txtask);
648 if (!list_empty(&pio->queue2->txqueue))
649 tasklet_schedule(&pio->queue2->txtask);
650 if (!list_empty(&pio->queue3->txqueue))
651 tasklet_schedule(&pio->queue3->txtask);