Revert "Merge branch 'ath6kl-next' of master.kernel.org:/pub/scm/linux/kernel/git...
[linux-2.6/next.git] / drivers / net / wireless / b43legacy / pio.c
blob192251adf986c97579539025055f91c592f189bd
1 /*
3 Broadcom B43legacy wireless driver
5 PIO Transmission
7 Copyright (c) 2005 Michael Buesch <m@bues.ch>
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 "b43legacy.h"
27 #include "pio.h"
28 #include "main.h"
29 #include "xmit.h"
31 #include <linux/delay.h>
32 #include <linux/slab.h>
35 static void tx_start(struct b43legacy_pioqueue *queue)
37 b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
38 B43legacy_PIO_TXCTL_INIT);
41 static void tx_octet(struct b43legacy_pioqueue *queue,
42 u8 octet)
44 if (queue->need_workarounds) {
45 b43legacy_pio_write(queue, B43legacy_PIO_TXDATA, octet);
46 b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
47 B43legacy_PIO_TXCTL_WRITELO);
48 } else {
49 b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
50 B43legacy_PIO_TXCTL_WRITELO);
51 b43legacy_pio_write(queue, B43legacy_PIO_TXDATA, octet);
55 static u16 tx_get_next_word(const u8 *txhdr,
56 const u8 *packet,
57 size_t txhdr_size,
58 unsigned int *pos)
60 const u8 *source;
61 unsigned int i = *pos;
62 u16 ret;
64 if (i < txhdr_size)
65 source = txhdr;
66 else {
67 source = packet;
68 i -= txhdr_size;
70 ret = le16_to_cpu(*((__le16 *)(source + i)));
71 *pos += 2;
73 return ret;
76 static void tx_data(struct b43legacy_pioqueue *queue,
77 u8 *txhdr,
78 const u8 *packet,
79 unsigned int octets)
81 u16 data;
82 unsigned int i = 0;
84 if (queue->need_workarounds) {
85 data = tx_get_next_word(txhdr, packet,
86 sizeof(struct b43legacy_txhdr_fw3), &i);
87 b43legacy_pio_write(queue, B43legacy_PIO_TXDATA, data);
89 b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
90 B43legacy_PIO_TXCTL_WRITELO |
91 B43legacy_PIO_TXCTL_WRITEHI);
92 while (i < octets - 1) {
93 data = tx_get_next_word(txhdr, packet,
94 sizeof(struct b43legacy_txhdr_fw3), &i);
95 b43legacy_pio_write(queue, B43legacy_PIO_TXDATA, data);
97 if (octets % 2)
98 tx_octet(queue, packet[octets -
99 sizeof(struct b43legacy_txhdr_fw3) - 1]);
102 static void tx_complete(struct b43legacy_pioqueue *queue,
103 struct sk_buff *skb)
105 if (queue->need_workarounds) {
106 b43legacy_pio_write(queue, B43legacy_PIO_TXDATA,
107 skb->data[skb->len - 1]);
108 b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
109 B43legacy_PIO_TXCTL_WRITELO |
110 B43legacy_PIO_TXCTL_COMPLETE);
111 } else
112 b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
113 B43legacy_PIO_TXCTL_COMPLETE);
116 static u16 generate_cookie(struct b43legacy_pioqueue *queue,
117 struct b43legacy_pio_txpacket *packet)
119 u16 cookie = 0x0000;
120 int packetindex;
122 /* We use the upper 4 bits for the PIO
123 * controller ID and the lower 12 bits
124 * for the packet index (in the cache).
126 switch (queue->mmio_base) {
127 case B43legacy_MMIO_PIO1_BASE:
128 break;
129 case B43legacy_MMIO_PIO2_BASE:
130 cookie = 0x1000;
131 break;
132 case B43legacy_MMIO_PIO3_BASE:
133 cookie = 0x2000;
134 break;
135 case B43legacy_MMIO_PIO4_BASE:
136 cookie = 0x3000;
137 break;
138 default:
139 B43legacy_WARN_ON(1);
141 packetindex = pio_txpacket_getindex(packet);
142 B43legacy_WARN_ON(!(((u16)packetindex & 0xF000) == 0x0000));
143 cookie |= (u16)packetindex;
145 return cookie;
148 static
149 struct b43legacy_pioqueue *parse_cookie(struct b43legacy_wldev *dev,
150 u16 cookie,
151 struct b43legacy_pio_txpacket **packet)
153 struct b43legacy_pio *pio = &dev->pio;
154 struct b43legacy_pioqueue *queue = NULL;
155 int packetindex;
157 switch (cookie & 0xF000) {
158 case 0x0000:
159 queue = pio->queue0;
160 break;
161 case 0x1000:
162 queue = pio->queue1;
163 break;
164 case 0x2000:
165 queue = pio->queue2;
166 break;
167 case 0x3000:
168 queue = pio->queue3;
169 break;
170 default:
171 B43legacy_WARN_ON(1);
173 packetindex = (cookie & 0x0FFF);
174 B43legacy_WARN_ON(!(packetindex >= 0 && packetindex
175 < B43legacy_PIO_MAXTXPACKETS));
176 *packet = &(queue->tx_packets_cache[packetindex]);
178 return queue;
181 union txhdr_union {
182 struct b43legacy_txhdr_fw3 txhdr_fw3;
185 static int pio_tx_write_fragment(struct b43legacy_pioqueue *queue,
186 struct sk_buff *skb,
187 struct b43legacy_pio_txpacket *packet,
188 size_t txhdr_size)
190 union txhdr_union txhdr_data;
191 u8 *txhdr = NULL;
192 unsigned int octets;
193 int err;
195 txhdr = (u8 *)(&txhdr_data.txhdr_fw3);
197 B43legacy_WARN_ON(skb_shinfo(skb)->nr_frags != 0);
198 err = b43legacy_generate_txhdr(queue->dev,
199 txhdr, skb->data, skb->len,
200 IEEE80211_SKB_CB(skb),
201 generate_cookie(queue, packet));
202 if (err)
203 return err;
205 tx_start(queue);
206 octets = skb->len + txhdr_size;
207 if (queue->need_workarounds)
208 octets--;
209 tx_data(queue, txhdr, (u8 *)skb->data, octets);
210 tx_complete(queue, skb);
212 return 0;
215 static void free_txpacket(struct b43legacy_pio_txpacket *packet,
216 int irq_context)
218 struct b43legacy_pioqueue *queue = packet->queue;
220 if (packet->skb) {
221 if (irq_context)
222 dev_kfree_skb_irq(packet->skb);
223 else
224 dev_kfree_skb(packet->skb);
226 list_move(&packet->list, &queue->txfree);
227 queue->nr_txfree++;
230 static int pio_tx_packet(struct b43legacy_pio_txpacket *packet)
232 struct b43legacy_pioqueue *queue = packet->queue;
233 struct sk_buff *skb = packet->skb;
234 u16 octets;
235 int err;
237 octets = (u16)skb->len + sizeof(struct b43legacy_txhdr_fw3);
238 if (queue->tx_devq_size < octets) {
239 b43legacywarn(queue->dev->wl, "PIO queue too small. "
240 "Dropping packet.\n");
241 /* Drop it silently (return success) */
242 free_txpacket(packet, 1);
243 return 0;
245 B43legacy_WARN_ON(queue->tx_devq_packets >
246 B43legacy_PIO_MAXTXDEVQPACKETS);
247 B43legacy_WARN_ON(queue->tx_devq_used > queue->tx_devq_size);
248 /* Check if there is sufficient free space on the device
249 * TX queue. If not, return and let the TX tasklet
250 * retry later.
252 if (queue->tx_devq_packets == B43legacy_PIO_MAXTXDEVQPACKETS)
253 return -EBUSY;
254 if (queue->tx_devq_used + octets > queue->tx_devq_size)
255 return -EBUSY;
256 /* Now poke the device. */
257 err = pio_tx_write_fragment(queue, skb, packet,
258 sizeof(struct b43legacy_txhdr_fw3));
259 if (unlikely(err == -ENOKEY)) {
260 /* Drop this packet, as we don't have the encryption key
261 * anymore and must not transmit it unencrypted. */
262 free_txpacket(packet, 1);
263 return 0;
266 /* Account for the packet size.
267 * (We must not overflow the device TX queue)
269 queue->tx_devq_packets++;
270 queue->tx_devq_used += octets;
272 /* Transmission started, everything ok, move the
273 * packet to the txrunning list.
275 list_move_tail(&packet->list, &queue->txrunning);
277 return 0;
280 static void tx_tasklet(unsigned long d)
282 struct b43legacy_pioqueue *queue = (struct b43legacy_pioqueue *)d;
283 struct b43legacy_wldev *dev = queue->dev;
284 unsigned long flags;
285 struct b43legacy_pio_txpacket *packet, *tmp_packet;
286 int err;
287 u16 txctl;
289 spin_lock_irqsave(&dev->wl->irq_lock, flags);
290 if (queue->tx_frozen)
291 goto out_unlock;
292 txctl = b43legacy_pio_read(queue, B43legacy_PIO_TXCTL);
293 if (txctl & B43legacy_PIO_TXCTL_SUSPEND)
294 goto out_unlock;
296 list_for_each_entry_safe(packet, tmp_packet, &queue->txqueue, list) {
297 /* Try to transmit the packet. This can fail, if
298 * the device queue is full. In case of failure, the
299 * packet is left in the txqueue.
300 * If transmission succeed, the packet is moved to txrunning.
301 * If it is impossible to transmit the packet, it
302 * is dropped.
304 err = pio_tx_packet(packet);
305 if (err)
306 break;
308 out_unlock:
309 spin_unlock_irqrestore(&dev->wl->irq_lock, flags);
312 static void setup_txqueues(struct b43legacy_pioqueue *queue)
314 struct b43legacy_pio_txpacket *packet;
315 int i;
317 queue->nr_txfree = B43legacy_PIO_MAXTXPACKETS;
318 for (i = 0; i < B43legacy_PIO_MAXTXPACKETS; i++) {
319 packet = &(queue->tx_packets_cache[i]);
321 packet->queue = queue;
322 INIT_LIST_HEAD(&packet->list);
324 list_add(&packet->list, &queue->txfree);
328 static
329 struct b43legacy_pioqueue *b43legacy_setup_pioqueue(struct b43legacy_wldev *dev,
330 u16 pio_mmio_base)
332 struct b43legacy_pioqueue *queue;
333 u32 value;
334 u16 qsize;
336 queue = kzalloc(sizeof(*queue), GFP_KERNEL);
337 if (!queue)
338 goto out;
340 queue->dev = dev;
341 queue->mmio_base = pio_mmio_base;
342 queue->need_workarounds = (dev->dev->id.revision < 3);
344 INIT_LIST_HEAD(&queue->txfree);
345 INIT_LIST_HEAD(&queue->txqueue);
346 INIT_LIST_HEAD(&queue->txrunning);
347 tasklet_init(&queue->txtask, tx_tasklet,
348 (unsigned long)queue);
350 value = b43legacy_read32(dev, B43legacy_MMIO_MACCTL);
351 value &= ~B43legacy_MACCTL_BE;
352 b43legacy_write32(dev, B43legacy_MMIO_MACCTL, value);
354 qsize = b43legacy_read16(dev, queue->mmio_base
355 + B43legacy_PIO_TXQBUFSIZE);
356 if (qsize == 0) {
357 b43legacyerr(dev->wl, "This card does not support PIO "
358 "operation mode. Please use DMA mode "
359 "(module parameter pio=0).\n");
360 goto err_freequeue;
362 if (qsize <= B43legacy_PIO_TXQADJUST) {
363 b43legacyerr(dev->wl, "PIO tx device-queue too small (%u)\n",
364 qsize);
365 goto err_freequeue;
367 qsize -= B43legacy_PIO_TXQADJUST;
368 queue->tx_devq_size = qsize;
370 setup_txqueues(queue);
372 out:
373 return queue;
375 err_freequeue:
376 kfree(queue);
377 queue = NULL;
378 goto out;
381 static void cancel_transfers(struct b43legacy_pioqueue *queue)
383 struct b43legacy_pio_txpacket *packet, *tmp_packet;
385 tasklet_disable(&queue->txtask);
387 list_for_each_entry_safe(packet, tmp_packet, &queue->txrunning, list)
388 free_txpacket(packet, 0);
389 list_for_each_entry_safe(packet, tmp_packet, &queue->txqueue, list)
390 free_txpacket(packet, 0);
393 static void b43legacy_destroy_pioqueue(struct b43legacy_pioqueue *queue)
395 if (!queue)
396 return;
398 cancel_transfers(queue);
399 kfree(queue);
402 void b43legacy_pio_free(struct b43legacy_wldev *dev)
404 struct b43legacy_pio *pio;
406 if (!b43legacy_using_pio(dev))
407 return;
408 pio = &dev->pio;
410 b43legacy_destroy_pioqueue(pio->queue3);
411 pio->queue3 = NULL;
412 b43legacy_destroy_pioqueue(pio->queue2);
413 pio->queue2 = NULL;
414 b43legacy_destroy_pioqueue(pio->queue1);
415 pio->queue1 = NULL;
416 b43legacy_destroy_pioqueue(pio->queue0);
417 pio->queue0 = NULL;
420 int b43legacy_pio_init(struct b43legacy_wldev *dev)
422 struct b43legacy_pio *pio = &dev->pio;
423 struct b43legacy_pioqueue *queue;
424 int err = -ENOMEM;
426 queue = b43legacy_setup_pioqueue(dev, B43legacy_MMIO_PIO1_BASE);
427 if (!queue)
428 goto out;
429 pio->queue0 = queue;
431 queue = b43legacy_setup_pioqueue(dev, B43legacy_MMIO_PIO2_BASE);
432 if (!queue)
433 goto err_destroy0;
434 pio->queue1 = queue;
436 queue = b43legacy_setup_pioqueue(dev, B43legacy_MMIO_PIO3_BASE);
437 if (!queue)
438 goto err_destroy1;
439 pio->queue2 = queue;
441 queue = b43legacy_setup_pioqueue(dev, B43legacy_MMIO_PIO4_BASE);
442 if (!queue)
443 goto err_destroy2;
444 pio->queue3 = queue;
446 if (dev->dev->id.revision < 3)
447 dev->irq_mask |= B43legacy_IRQ_PIO_WORKAROUND;
449 b43legacydbg(dev->wl, "PIO initialized\n");
450 err = 0;
451 out:
452 return err;
454 err_destroy2:
455 b43legacy_destroy_pioqueue(pio->queue2);
456 pio->queue2 = NULL;
457 err_destroy1:
458 b43legacy_destroy_pioqueue(pio->queue1);
459 pio->queue1 = NULL;
460 err_destroy0:
461 b43legacy_destroy_pioqueue(pio->queue0);
462 pio->queue0 = NULL;
463 goto out;
466 int b43legacy_pio_tx(struct b43legacy_wldev *dev,
467 struct sk_buff *skb)
469 struct b43legacy_pioqueue *queue = dev->pio.queue1;
470 struct b43legacy_pio_txpacket *packet;
472 B43legacy_WARN_ON(queue->tx_suspended);
473 B43legacy_WARN_ON(list_empty(&queue->txfree));
475 packet = list_entry(queue->txfree.next, struct b43legacy_pio_txpacket,
476 list);
477 packet->skb = skb;
479 list_move_tail(&packet->list, &queue->txqueue);
480 queue->nr_txfree--;
481 B43legacy_WARN_ON(queue->nr_txfree >= B43legacy_PIO_MAXTXPACKETS);
483 tasklet_schedule(&queue->txtask);
485 return 0;
488 void b43legacy_pio_handle_txstatus(struct b43legacy_wldev *dev,
489 const struct b43legacy_txstatus *status)
491 struct b43legacy_pioqueue *queue;
492 struct b43legacy_pio_txpacket *packet;
493 struct ieee80211_tx_info *info;
494 int retry_limit;
496 queue = parse_cookie(dev, status->cookie, &packet);
497 B43legacy_WARN_ON(!queue);
499 if (!packet->skb)
500 return;
502 queue->tx_devq_packets--;
503 queue->tx_devq_used -= (packet->skb->len +
504 sizeof(struct b43legacy_txhdr_fw3));
506 info = IEEE80211_SKB_CB(packet->skb);
508 /* preserve the confiured retry limit before clearing the status
509 * The xmit function has overwritten the rc's value with the actual
510 * retry limit done by the hardware */
511 retry_limit = info->status.rates[0].count;
512 ieee80211_tx_info_clear_status(info);
514 if (status->acked)
515 info->flags |= IEEE80211_TX_STAT_ACK;
517 if (status->rts_count > dev->wl->hw->conf.short_frame_max_tx_count) {
519 * If the short retries (RTS, not data frame) have exceeded
520 * the limit, the hw will not have tried the selected rate,
521 * but will have used the fallback rate instead.
522 * Don't let the rate control count attempts for the selected
523 * rate in this case, otherwise the statistics will be off.
525 info->status.rates[0].count = 0;
526 info->status.rates[1].count = status->frame_count;
527 } else {
528 if (status->frame_count > retry_limit) {
529 info->status.rates[0].count = retry_limit;
530 info->status.rates[1].count = status->frame_count -
531 retry_limit;
533 } else {
534 info->status.rates[0].count = status->frame_count;
535 info->status.rates[1].idx = -1;
538 ieee80211_tx_status_irqsafe(dev->wl->hw, packet->skb);
539 packet->skb = NULL;
541 free_txpacket(packet, 1);
542 /* If there are packets on the txqueue, poke the tasklet
543 * to transmit them.
545 if (!list_empty(&queue->txqueue))
546 tasklet_schedule(&queue->txtask);
549 static void pio_rx_error(struct b43legacy_pioqueue *queue,
550 int clear_buffers,
551 const char *error)
553 int i;
555 b43legacyerr(queue->dev->wl, "PIO RX error: %s\n", error);
556 b43legacy_pio_write(queue, B43legacy_PIO_RXCTL,
557 B43legacy_PIO_RXCTL_READY);
558 if (clear_buffers) {
559 B43legacy_WARN_ON(queue->mmio_base != B43legacy_MMIO_PIO1_BASE);
560 for (i = 0; i < 15; i++) {
561 /* Dummy read. */
562 b43legacy_pio_read(queue, B43legacy_PIO_RXDATA);
567 void b43legacy_pio_rx(struct b43legacy_pioqueue *queue)
569 __le16 preamble[21] = { 0 };
570 struct b43legacy_rxhdr_fw3 *rxhdr;
571 u16 tmp;
572 u16 len;
573 u16 macstat;
574 int i;
575 int preamble_readwords;
576 struct sk_buff *skb;
578 tmp = b43legacy_pio_read(queue, B43legacy_PIO_RXCTL);
579 if (!(tmp & B43legacy_PIO_RXCTL_DATAAVAILABLE))
580 return;
581 b43legacy_pio_write(queue, B43legacy_PIO_RXCTL,
582 B43legacy_PIO_RXCTL_DATAAVAILABLE);
584 for (i = 0; i < 10; i++) {
585 tmp = b43legacy_pio_read(queue, B43legacy_PIO_RXCTL);
586 if (tmp & B43legacy_PIO_RXCTL_READY)
587 goto data_ready;
588 udelay(10);
590 b43legacydbg(queue->dev->wl, "PIO RX timed out\n");
591 return;
592 data_ready:
594 len = b43legacy_pio_read(queue, B43legacy_PIO_RXDATA);
595 if (unlikely(len > 0x700)) {
596 pio_rx_error(queue, 0, "len > 0x700");
597 return;
599 if (unlikely(len == 0 && queue->mmio_base !=
600 B43legacy_MMIO_PIO4_BASE)) {
601 pio_rx_error(queue, 0, "len == 0");
602 return;
604 preamble[0] = cpu_to_le16(len);
605 if (queue->mmio_base == B43legacy_MMIO_PIO4_BASE)
606 preamble_readwords = 14 / sizeof(u16);
607 else
608 preamble_readwords = 18 / sizeof(u16);
609 for (i = 0; i < preamble_readwords; i++) {
610 tmp = b43legacy_pio_read(queue, B43legacy_PIO_RXDATA);
611 preamble[i + 1] = cpu_to_le16(tmp);
613 rxhdr = (struct b43legacy_rxhdr_fw3 *)preamble;
614 macstat = le16_to_cpu(rxhdr->mac_status);
615 if (macstat & B43legacy_RX_MAC_FCSERR) {
616 pio_rx_error(queue,
617 (queue->mmio_base == B43legacy_MMIO_PIO1_BASE),
618 "Frame FCS error");
619 return;
621 if (queue->mmio_base == B43legacy_MMIO_PIO4_BASE) {
622 /* We received an xmit status. */
623 struct b43legacy_hwtxstatus *hw;
625 hw = (struct b43legacy_hwtxstatus *)(preamble + 1);
626 b43legacy_handle_hwtxstatus(queue->dev, hw);
628 return;
631 skb = dev_alloc_skb(len);
632 if (unlikely(!skb)) {
633 pio_rx_error(queue, 1, "OOM");
634 return;
636 skb_put(skb, len);
637 for (i = 0; i < len - 1; i += 2) {
638 tmp = b43legacy_pio_read(queue, B43legacy_PIO_RXDATA);
639 *((__le16 *)(skb->data + i)) = cpu_to_le16(tmp);
641 if (len % 2) {
642 tmp = b43legacy_pio_read(queue, B43legacy_PIO_RXDATA);
643 skb->data[len - 1] = (tmp & 0x00FF);
645 b43legacy_rx(queue->dev, skb, rxhdr);
648 void b43legacy_pio_tx_suspend(struct b43legacy_pioqueue *queue)
650 b43legacy_power_saving_ctl_bits(queue->dev, -1, 1);
651 b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
652 b43legacy_pio_read(queue, B43legacy_PIO_TXCTL)
653 | B43legacy_PIO_TXCTL_SUSPEND);
656 void b43legacy_pio_tx_resume(struct b43legacy_pioqueue *queue)
658 b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
659 b43legacy_pio_read(queue, B43legacy_PIO_TXCTL)
660 & ~B43legacy_PIO_TXCTL_SUSPEND);
661 b43legacy_power_saving_ctl_bits(queue->dev, -1, -1);
662 tasklet_schedule(&queue->txtask);
665 void b43legacy_pio_freeze_txqueues(struct b43legacy_wldev *dev)
667 struct b43legacy_pio *pio;
669 B43legacy_WARN_ON(!b43legacy_using_pio(dev));
670 pio = &dev->pio;
671 pio->queue0->tx_frozen = 1;
672 pio->queue1->tx_frozen = 1;
673 pio->queue2->tx_frozen = 1;
674 pio->queue3->tx_frozen = 1;
677 void b43legacy_pio_thaw_txqueues(struct b43legacy_wldev *dev)
679 struct b43legacy_pio *pio;
681 B43legacy_WARN_ON(!b43legacy_using_pio(dev));
682 pio = &dev->pio;
683 pio->queue0->tx_frozen = 0;
684 pio->queue1->tx_frozen = 0;
685 pio->queue2->tx_frozen = 0;
686 pio->queue3->tx_frozen = 0;
687 if (!list_empty(&pio->queue0->txqueue))
688 tasklet_schedule(&pio->queue0->txtask);
689 if (!list_empty(&pio->queue1->txqueue))
690 tasklet_schedule(&pio->queue1->txtask);
691 if (!list_empty(&pio->queue2->txqueue))
692 tasklet_schedule(&pio->queue2->txtask);
693 if (!list_empty(&pio->queue3->txqueue))
694 tasklet_schedule(&pio->queue3->txtask);