xref: /linux/drivers/net/wireless/broadcom/b43legacy/pio.c (revision cbecf716ca618fd44feda6bd9a64a8179d031fc5)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 
4   Broadcom B43legacy wireless driver
5 
6   PIO Transmission
7 
8   Copyright (c) 2005 Michael Buesch <m@bues.ch>
9 
10 
11 */
12 
13 #include "b43legacy.h"
14 #include "pio.h"
15 #include "main.h"
16 #include "xmit.h"
17 
18 #include <linux/delay.h>
19 #include <linux/slab.h>
20 
21 
tx_start(struct b43legacy_pioqueue * queue)22 static void tx_start(struct b43legacy_pioqueue *queue)
23 {
24 	b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
25 			    B43legacy_PIO_TXCTL_INIT);
26 }
27 
tx_octet(struct b43legacy_pioqueue * queue,u8 octet)28 static void tx_octet(struct b43legacy_pioqueue *queue,
29 		     u8 octet)
30 {
31 	if (queue->need_workarounds) {
32 		b43legacy_pio_write(queue, B43legacy_PIO_TXDATA, octet);
33 		b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
34 				    B43legacy_PIO_TXCTL_WRITELO);
35 	} else {
36 		b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
37 				    B43legacy_PIO_TXCTL_WRITELO);
38 		b43legacy_pio_write(queue, B43legacy_PIO_TXDATA, octet);
39 	}
40 }
41 
tx_get_next_word(const u8 * txhdr,const u8 * packet,size_t txhdr_size,unsigned int * pos)42 static u16 tx_get_next_word(const u8 *txhdr,
43 			    const u8 *packet,
44 			    size_t txhdr_size,
45 			    unsigned int *pos)
46 {
47 	const u8 *source;
48 	unsigned int i = *pos;
49 	u16 ret;
50 
51 	if (i < txhdr_size)
52 		source = txhdr;
53 	else {
54 		source = packet;
55 		i -= txhdr_size;
56 	}
57 	ret = le16_to_cpu(*((__le16 *)(source + i)));
58 	*pos += 2;
59 
60 	return ret;
61 }
62 
tx_data(struct b43legacy_pioqueue * queue,u8 * txhdr,const u8 * packet,unsigned int octets)63 static void tx_data(struct b43legacy_pioqueue *queue,
64 		    u8 *txhdr,
65 		    const u8 *packet,
66 		    unsigned int octets)
67 {
68 	u16 data;
69 	unsigned int i = 0;
70 
71 	if (queue->need_workarounds) {
72 		data = tx_get_next_word(txhdr, packet,
73 					sizeof(struct b43legacy_txhdr_fw3), &i);
74 		b43legacy_pio_write(queue, B43legacy_PIO_TXDATA, data);
75 	}
76 	b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
77 			    B43legacy_PIO_TXCTL_WRITELO |
78 			    B43legacy_PIO_TXCTL_WRITEHI);
79 	while (i < octets - 1) {
80 		data = tx_get_next_word(txhdr, packet,
81 					sizeof(struct b43legacy_txhdr_fw3), &i);
82 		b43legacy_pio_write(queue, B43legacy_PIO_TXDATA, data);
83 	}
84 	if (octets % 2)
85 		tx_octet(queue, packet[octets -
86 			 sizeof(struct b43legacy_txhdr_fw3) - 1]);
87 }
88 
tx_complete(struct b43legacy_pioqueue * queue,struct sk_buff * skb)89 static void tx_complete(struct b43legacy_pioqueue *queue,
90 			struct sk_buff *skb)
91 {
92 	if (queue->need_workarounds) {
93 		b43legacy_pio_write(queue, B43legacy_PIO_TXDATA,
94 				    skb->data[skb->len - 1]);
95 		b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
96 				    B43legacy_PIO_TXCTL_WRITELO |
97 				    B43legacy_PIO_TXCTL_COMPLETE);
98 	} else
99 		b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
100 				    B43legacy_PIO_TXCTL_COMPLETE);
101 }
102 
generate_cookie(struct b43legacy_pioqueue * queue,struct b43legacy_pio_txpacket * packet)103 static u16 generate_cookie(struct b43legacy_pioqueue *queue,
104 			   struct b43legacy_pio_txpacket *packet)
105 {
106 	u16 cookie = 0x0000;
107 	int packetindex;
108 
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).
112 	 */
113 	switch (queue->mmio_base) {
114 	case B43legacy_MMIO_PIO1_BASE:
115 		break;
116 	case B43legacy_MMIO_PIO2_BASE:
117 		cookie = 0x1000;
118 		break;
119 	case B43legacy_MMIO_PIO3_BASE:
120 		cookie = 0x2000;
121 		break;
122 	case B43legacy_MMIO_PIO4_BASE:
123 		cookie = 0x3000;
124 		break;
125 	default:
126 		B43legacy_WARN_ON(1);
127 	}
128 	packetindex = pio_txpacket_getindex(packet);
129 	B43legacy_WARN_ON(!(((u16)packetindex & 0xF000) == 0x0000));
130 	cookie |= (u16)packetindex;
131 
132 	return cookie;
133 }
134 
135 static
parse_cookie(struct b43legacy_wldev * dev,u16 cookie,struct b43legacy_pio_txpacket ** packet)136 struct b43legacy_pioqueue *parse_cookie(struct b43legacy_wldev *dev,
137 					u16 cookie,
138 					struct b43legacy_pio_txpacket **packet)
139 {
140 	struct b43legacy_pio *pio = &dev->pio;
141 	struct b43legacy_pioqueue *queue = NULL;
142 	int packetindex;
143 
144 	switch (cookie & 0xF000) {
145 	case 0x0000:
146 		queue = pio->queue0;
147 		break;
148 	case 0x1000:
149 		queue = pio->queue1;
150 		break;
151 	case 0x2000:
152 		queue = pio->queue2;
153 		break;
154 	case 0x3000:
155 		queue = pio->queue3;
156 		break;
157 	default:
158 		B43legacy_WARN_ON(1);
159 	}
160 	packetindex = (cookie & 0x0FFF);
161 	B43legacy_WARN_ON(!(packetindex >= 0 && packetindex
162 			  < B43legacy_PIO_MAXTXPACKETS));
163 	*packet = &(queue->tx_packets_cache[packetindex]);
164 
165 	return queue;
166 }
167 
168 union txhdr_union {
169 	struct b43legacy_txhdr_fw3 txhdr_fw3;
170 };
171 
pio_tx_write_fragment(struct b43legacy_pioqueue * queue,struct sk_buff * skb,struct b43legacy_pio_txpacket * packet,size_t txhdr_size)172 static int pio_tx_write_fragment(struct b43legacy_pioqueue *queue,
173 				  struct sk_buff *skb,
174 				  struct b43legacy_pio_txpacket *packet,
175 				  size_t txhdr_size)
176 {
177 	union txhdr_union txhdr_data;
178 	u8 *txhdr = NULL;
179 	unsigned int octets;
180 	int err;
181 
182 	txhdr = (u8 *)(&txhdr_data.txhdr_fw3);
183 
184 	B43legacy_WARN_ON(skb_shinfo(skb)->nr_frags != 0);
185 	err = b43legacy_generate_txhdr(queue->dev,
186 				 txhdr, skb->data, skb->len,
187 				 IEEE80211_SKB_CB(skb),
188 				 generate_cookie(queue, packet));
189 	if (err)
190 		return err;
191 
192 	tx_start(queue);
193 	octets = skb->len + txhdr_size;
194 	if (queue->need_workarounds)
195 		octets--;
196 	tx_data(queue, txhdr, (u8 *)skb->data, octets);
197 	tx_complete(queue, skb);
198 
199 	return 0;
200 }
201 
free_txpacket(struct b43legacy_pio_txpacket * packet,int irq_context)202 static void free_txpacket(struct b43legacy_pio_txpacket *packet,
203 			  int irq_context)
204 {
205 	struct b43legacy_pioqueue *queue = packet->queue;
206 
207 	if (packet->skb) {
208 		if (irq_context)
209 			dev_kfree_skb_irq(packet->skb);
210 		else
211 			dev_kfree_skb(packet->skb);
212 	}
213 	list_move(&packet->list, &queue->txfree);
214 	queue->nr_txfree++;
215 }
216 
pio_tx_packet(struct b43legacy_pio_txpacket * packet)217 static int pio_tx_packet(struct b43legacy_pio_txpacket *packet)
218 {
219 	struct b43legacy_pioqueue *queue = packet->queue;
220 	struct sk_buff *skb = packet->skb;
221 	u16 octets;
222 	int err;
223 
224 	octets = (u16)skb->len + sizeof(struct b43legacy_txhdr_fw3);
225 	if (queue->tx_devq_size < octets) {
226 		b43legacywarn(queue->dev->wl, "PIO queue too small. "
227 			"Dropping packet.\n");
228 		/* Drop it silently (return success) */
229 		free_txpacket(packet, 1);
230 		return 0;
231 	}
232 	B43legacy_WARN_ON(queue->tx_devq_packets >
233 			  B43legacy_PIO_MAXTXDEVQPACKETS);
234 	B43legacy_WARN_ON(queue->tx_devq_used > queue->tx_devq_size);
235 	/* Check if there is sufficient free space on the device
236 	 * TX queue. If not, return and let the TX tasklet
237 	 * retry later.
238 	 */
239 	if (queue->tx_devq_packets == B43legacy_PIO_MAXTXDEVQPACKETS)
240 		return -EBUSY;
241 	if (queue->tx_devq_used + octets > queue->tx_devq_size)
242 		return -EBUSY;
243 	/* Now poke the device. */
244 	err = pio_tx_write_fragment(queue, skb, packet,
245 			      sizeof(struct b43legacy_txhdr_fw3));
246 	if (unlikely(err == -ENOKEY)) {
247 		/* Drop this packet, as we don't have the encryption key
248 		 * anymore and must not transmit it unencrypted. */
249 		free_txpacket(packet, 1);
250 		return 0;
251 	}
252 
253 	/* Account for the packet size.
254 	 * (We must not overflow the device TX queue)
255 	 */
256 	queue->tx_devq_packets++;
257 	queue->tx_devq_used += octets;
258 
259 	/* Transmission started, everything ok, move the
260 	 * packet to the txrunning list.
261 	 */
262 	list_move_tail(&packet->list, &queue->txrunning);
263 
264 	return 0;
265 }
266 
tx_tasklet(struct tasklet_struct * t)267 static void tx_tasklet(struct tasklet_struct *t)
268 {
269 	struct b43legacy_pioqueue *queue = from_tasklet(queue, t, txtask);
270 	struct b43legacy_wldev *dev = queue->dev;
271 	unsigned long flags;
272 	struct b43legacy_pio_txpacket *packet, *tmp_packet;
273 	int err;
274 	u16 txctl;
275 
276 	spin_lock_irqsave(&dev->wl->irq_lock, flags);
277 	if (queue->tx_frozen)
278 		goto out_unlock;
279 	txctl = b43legacy_pio_read(queue, B43legacy_PIO_TXCTL);
280 	if (txctl & B43legacy_PIO_TXCTL_SUSPEND)
281 		goto out_unlock;
282 
283 	list_for_each_entry_safe(packet, tmp_packet, &queue->txqueue, list) {
284 		/* Try to transmit the packet. This can fail, if
285 		 * the device queue is full. In case of failure, the
286 		 * packet is left in the txqueue.
287 		 * If transmission succeed, the packet is moved to txrunning.
288 		 * If it is impossible to transmit the packet, it
289 		 * is dropped.
290 		 */
291 		err = pio_tx_packet(packet);
292 		if (err)
293 			break;
294 	}
295 out_unlock:
296 	spin_unlock_irqrestore(&dev->wl->irq_lock, flags);
297 }
298 
setup_txqueues(struct b43legacy_pioqueue * queue)299 static void setup_txqueues(struct b43legacy_pioqueue *queue)
300 {
301 	struct b43legacy_pio_txpacket *packet;
302 	int i;
303 
304 	queue->nr_txfree = B43legacy_PIO_MAXTXPACKETS;
305 	for (i = 0; i < B43legacy_PIO_MAXTXPACKETS; i++) {
306 		packet = &(queue->tx_packets_cache[i]);
307 
308 		packet->queue = queue;
309 		INIT_LIST_HEAD(&packet->list);
310 
311 		list_add(&packet->list, &queue->txfree);
312 	}
313 }
314 
315 static
b43legacy_setup_pioqueue(struct b43legacy_wldev * dev,u16 pio_mmio_base)316 struct b43legacy_pioqueue *b43legacy_setup_pioqueue(struct b43legacy_wldev *dev,
317 						    u16 pio_mmio_base)
318 {
319 	struct b43legacy_pioqueue *queue;
320 	u32 value;
321 	u16 qsize;
322 
323 	queue = kzalloc(sizeof(*queue), GFP_KERNEL);
324 	if (!queue)
325 		goto out;
326 
327 	queue->dev = dev;
328 	queue->mmio_base = pio_mmio_base;
329 	queue->need_workarounds = (dev->dev->id.revision < 3);
330 
331 	INIT_LIST_HEAD(&queue->txfree);
332 	INIT_LIST_HEAD(&queue->txqueue);
333 	INIT_LIST_HEAD(&queue->txrunning);
334 	tasklet_setup(&queue->txtask, tx_tasklet);
335 
336 	value = b43legacy_read32(dev, B43legacy_MMIO_MACCTL);
337 	value &= ~B43legacy_MACCTL_BE;
338 	b43legacy_write32(dev, B43legacy_MMIO_MACCTL, value);
339 
340 	qsize = b43legacy_read16(dev, queue->mmio_base
341 				 + B43legacy_PIO_TXQBUFSIZE);
342 	if (qsize == 0) {
343 		b43legacyerr(dev->wl, "This card does not support PIO "
344 		       "operation mode. Please use DMA mode "
345 		       "(module parameter pio=0).\n");
346 		goto err_freequeue;
347 	}
348 	if (qsize <= B43legacy_PIO_TXQADJUST) {
349 		b43legacyerr(dev->wl, "PIO tx device-queue too small (%u)\n",
350 		       qsize);
351 		goto err_freequeue;
352 	}
353 	qsize -= B43legacy_PIO_TXQADJUST;
354 	queue->tx_devq_size = qsize;
355 
356 	setup_txqueues(queue);
357 
358 out:
359 	return queue;
360 
361 err_freequeue:
362 	kfree(queue);
363 	queue = NULL;
364 	goto out;
365 }
366 
cancel_transfers(struct b43legacy_pioqueue * queue)367 static void cancel_transfers(struct b43legacy_pioqueue *queue)
368 {
369 	struct b43legacy_pio_txpacket *packet, *tmp_packet;
370 
371 	tasklet_kill(&queue->txtask);
372 
373 	list_for_each_entry_safe(packet, tmp_packet, &queue->txrunning, list)
374 		free_txpacket(packet, 0);
375 	list_for_each_entry_safe(packet, tmp_packet, &queue->txqueue, list)
376 		free_txpacket(packet, 0);
377 }
378 
b43legacy_destroy_pioqueue(struct b43legacy_pioqueue * queue)379 static void b43legacy_destroy_pioqueue(struct b43legacy_pioqueue *queue)
380 {
381 	if (!queue)
382 		return;
383 
384 	cancel_transfers(queue);
385 	kfree(queue);
386 }
387 
b43legacy_pio_free(struct b43legacy_wldev * dev)388 void b43legacy_pio_free(struct b43legacy_wldev *dev)
389 {
390 	struct b43legacy_pio *pio;
391 
392 	if (!b43legacy_using_pio(dev))
393 		return;
394 	pio = &dev->pio;
395 
396 	b43legacy_destroy_pioqueue(pio->queue3);
397 	pio->queue3 = NULL;
398 	b43legacy_destroy_pioqueue(pio->queue2);
399 	pio->queue2 = NULL;
400 	b43legacy_destroy_pioqueue(pio->queue1);
401 	pio->queue1 = NULL;
402 	b43legacy_destroy_pioqueue(pio->queue0);
403 	pio->queue0 = NULL;
404 }
405 
b43legacy_pio_init(struct b43legacy_wldev * dev)406 int b43legacy_pio_init(struct b43legacy_wldev *dev)
407 {
408 	struct b43legacy_pio *pio = &dev->pio;
409 	struct b43legacy_pioqueue *queue;
410 	int err = -ENOMEM;
411 
412 	queue = b43legacy_setup_pioqueue(dev, B43legacy_MMIO_PIO1_BASE);
413 	if (!queue)
414 		goto out;
415 	pio->queue0 = queue;
416 
417 	queue = b43legacy_setup_pioqueue(dev, B43legacy_MMIO_PIO2_BASE);
418 	if (!queue)
419 		goto err_destroy0;
420 	pio->queue1 = queue;
421 
422 	queue = b43legacy_setup_pioqueue(dev, B43legacy_MMIO_PIO3_BASE);
423 	if (!queue)
424 		goto err_destroy1;
425 	pio->queue2 = queue;
426 
427 	queue = b43legacy_setup_pioqueue(dev, B43legacy_MMIO_PIO4_BASE);
428 	if (!queue)
429 		goto err_destroy2;
430 	pio->queue3 = queue;
431 
432 	if (dev->dev->id.revision < 3)
433 		dev->irq_mask |= B43legacy_IRQ_PIO_WORKAROUND;
434 
435 	b43legacydbg(dev->wl, "PIO initialized\n");
436 	err = 0;
437 out:
438 	return err;
439 
440 err_destroy2:
441 	b43legacy_destroy_pioqueue(pio->queue2);
442 	pio->queue2 = NULL;
443 err_destroy1:
444 	b43legacy_destroy_pioqueue(pio->queue1);
445 	pio->queue1 = NULL;
446 err_destroy0:
447 	b43legacy_destroy_pioqueue(pio->queue0);
448 	pio->queue0 = NULL;
449 	goto out;
450 }
451 
b43legacy_pio_tx(struct b43legacy_wldev * dev,struct sk_buff * skb)452 int b43legacy_pio_tx(struct b43legacy_wldev *dev,
453 		     struct sk_buff *skb)
454 {
455 	struct b43legacy_pioqueue *queue = dev->pio.queue1;
456 	struct b43legacy_pio_txpacket *packet;
457 
458 	B43legacy_WARN_ON(queue->tx_suspended);
459 	B43legacy_WARN_ON(list_empty(&queue->txfree));
460 
461 	packet = list_entry(queue->txfree.next, struct b43legacy_pio_txpacket,
462 			    list);
463 	packet->skb = skb;
464 
465 	list_move_tail(&packet->list, &queue->txqueue);
466 	queue->nr_txfree--;
467 	B43legacy_WARN_ON(queue->nr_txfree >= B43legacy_PIO_MAXTXPACKETS);
468 
469 	tasklet_schedule(&queue->txtask);
470 
471 	return 0;
472 }
473 
b43legacy_pio_handle_txstatus(struct b43legacy_wldev * dev,const struct b43legacy_txstatus * status)474 void b43legacy_pio_handle_txstatus(struct b43legacy_wldev *dev,
475 				   const struct b43legacy_txstatus *status)
476 {
477 	struct b43legacy_pioqueue *queue;
478 	struct b43legacy_pio_txpacket *packet;
479 	struct ieee80211_tx_info *info;
480 	int retry_limit;
481 
482 	queue = parse_cookie(dev, status->cookie, &packet);
483 	B43legacy_WARN_ON(!queue);
484 
485 	if (!packet->skb)
486 		return;
487 
488 	queue->tx_devq_packets--;
489 	queue->tx_devq_used -= (packet->skb->len +
490 				sizeof(struct b43legacy_txhdr_fw3));
491 
492 	info = IEEE80211_SKB_CB(packet->skb);
493 
494 	/* preserve the confiured retry limit before clearing the status
495 	 * The xmit function has overwritten the rc's value with the actual
496 	 * retry limit done by the hardware */
497 	retry_limit = info->status.rates[0].count;
498 	ieee80211_tx_info_clear_status(info);
499 
500 	if (status->acked)
501 		info->flags |= IEEE80211_TX_STAT_ACK;
502 
503 	if (status->rts_count > dev->wl->hw->conf.short_frame_max_tx_count) {
504 		/*
505 		 * If the short retries (RTS, not data frame) have exceeded
506 		 * the limit, the hw will not have tried the selected rate,
507 		 * but will have used the fallback rate instead.
508 		 * Don't let the rate control count attempts for the selected
509 		 * rate in this case, otherwise the statistics will be off.
510 		 */
511 		info->status.rates[0].count = 0;
512 		info->status.rates[1].count = status->frame_count;
513 	} else {
514 		if (status->frame_count > retry_limit) {
515 			info->status.rates[0].count = retry_limit;
516 			info->status.rates[1].count = status->frame_count -
517 					retry_limit;
518 
519 		} else {
520 			info->status.rates[0].count = status->frame_count;
521 			info->status.rates[1].idx = -1;
522 		}
523 	}
524 	ieee80211_tx_status_irqsafe(dev->wl->hw, packet->skb);
525 	packet->skb = NULL;
526 
527 	free_txpacket(packet, 1);
528 	/* If there are packets on the txqueue, poke the tasklet
529 	 * to transmit them.
530 	 */
531 	if (!list_empty(&queue->txqueue))
532 		tasklet_schedule(&queue->txtask);
533 }
534 
pio_rx_error(struct b43legacy_pioqueue * queue,int clear_buffers,const char * error)535 static void pio_rx_error(struct b43legacy_pioqueue *queue,
536 			 int clear_buffers,
537 			 const char *error)
538 {
539 	int i;
540 
541 	b43legacyerr(queue->dev->wl, "PIO RX error: %s\n", error);
542 	b43legacy_pio_write(queue, B43legacy_PIO_RXCTL,
543 			    B43legacy_PIO_RXCTL_READY);
544 	if (clear_buffers) {
545 		B43legacy_WARN_ON(queue->mmio_base != B43legacy_MMIO_PIO1_BASE);
546 		for (i = 0; i < 15; i++) {
547 			/* Dummy read. */
548 			b43legacy_pio_read(queue, B43legacy_PIO_RXDATA);
549 		}
550 	}
551 }
552 
b43legacy_pio_rx(struct b43legacy_pioqueue * queue)553 void b43legacy_pio_rx(struct b43legacy_pioqueue *queue)
554 {
555 	__le16 preamble[21] = { 0 };
556 	struct b43legacy_rxhdr_fw3 *rxhdr;
557 	u16 tmp;
558 	u16 len;
559 	u16 macstat;
560 	int i;
561 	int preamble_readwords;
562 	struct sk_buff *skb;
563 
564 	tmp = b43legacy_pio_read(queue, B43legacy_PIO_RXCTL);
565 	if (!(tmp & B43legacy_PIO_RXCTL_DATAAVAILABLE))
566 		return;
567 	b43legacy_pio_write(queue, B43legacy_PIO_RXCTL,
568 			    B43legacy_PIO_RXCTL_DATAAVAILABLE);
569 
570 	for (i = 0; i < 10; i++) {
571 		tmp = b43legacy_pio_read(queue, B43legacy_PIO_RXCTL);
572 		if (tmp & B43legacy_PIO_RXCTL_READY)
573 			goto data_ready;
574 		udelay(10);
575 	}
576 	b43legacydbg(queue->dev->wl, "PIO RX timed out\n");
577 	return;
578 data_ready:
579 
580 	len = b43legacy_pio_read(queue, B43legacy_PIO_RXDATA);
581 	if (unlikely(len > 0x700)) {
582 		pio_rx_error(queue, 0, "len > 0x700");
583 		return;
584 	}
585 	if (unlikely(len == 0 && queue->mmio_base !=
586 		     B43legacy_MMIO_PIO4_BASE)) {
587 		pio_rx_error(queue, 0, "len == 0");
588 		return;
589 	}
590 	preamble[0] = cpu_to_le16(len);
591 	if (queue->mmio_base == B43legacy_MMIO_PIO4_BASE)
592 		preamble_readwords = 14 / sizeof(u16);
593 	else
594 		preamble_readwords = 18 / sizeof(u16);
595 	for (i = 0; i < preamble_readwords; i++) {
596 		tmp = b43legacy_pio_read(queue, B43legacy_PIO_RXDATA);
597 		preamble[i + 1] = cpu_to_le16(tmp);
598 	}
599 	rxhdr = (struct b43legacy_rxhdr_fw3 *)preamble;
600 	macstat = le16_to_cpu(rxhdr->mac_status);
601 	if (macstat & B43legacy_RX_MAC_FCSERR) {
602 		pio_rx_error(queue,
603 			     (queue->mmio_base == B43legacy_MMIO_PIO1_BASE),
604 			     "Frame FCS error");
605 		return;
606 	}
607 	if (queue->mmio_base == B43legacy_MMIO_PIO4_BASE) {
608 		/* We received an xmit status. */
609 		struct b43legacy_hwtxstatus *hw;
610 
611 		hw = (struct b43legacy_hwtxstatus *)(preamble + 1);
612 		b43legacy_handle_hwtxstatus(queue->dev, hw);
613 
614 		return;
615 	}
616 
617 	skb = dev_alloc_skb(len);
618 	if (unlikely(!skb)) {
619 		pio_rx_error(queue, 1, "OOM");
620 		return;
621 	}
622 	skb_put(skb, len);
623 	for (i = 0; i < len - 1; i += 2) {
624 		tmp = b43legacy_pio_read(queue, B43legacy_PIO_RXDATA);
625 		*((__le16 *)(skb->data + i)) = cpu_to_le16(tmp);
626 	}
627 	if (len % 2) {
628 		tmp = b43legacy_pio_read(queue, B43legacy_PIO_RXDATA);
629 		skb->data[len - 1] = (tmp & 0x00FF);
630 	}
631 	b43legacy_rx(queue->dev, skb, rxhdr);
632 }
633 
b43legacy_pio_tx_suspend(struct b43legacy_pioqueue * queue)634 void b43legacy_pio_tx_suspend(struct b43legacy_pioqueue *queue)
635 {
636 	b43legacy_power_saving_ctl_bits(queue->dev, -1, 1);
637 	b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
638 			    b43legacy_pio_read(queue, B43legacy_PIO_TXCTL)
639 			    | B43legacy_PIO_TXCTL_SUSPEND);
640 }
641 
b43legacy_pio_tx_resume(struct b43legacy_pioqueue * queue)642 void b43legacy_pio_tx_resume(struct b43legacy_pioqueue *queue)
643 {
644 	b43legacy_pio_write(queue, B43legacy_PIO_TXCTL,
645 			    b43legacy_pio_read(queue, B43legacy_PIO_TXCTL)
646 			    & ~B43legacy_PIO_TXCTL_SUSPEND);
647 	b43legacy_power_saving_ctl_bits(queue->dev, -1, -1);
648 	tasklet_schedule(&queue->txtask);
649 }
650 
b43legacy_pio_freeze_txqueues(struct b43legacy_wldev * dev)651 void b43legacy_pio_freeze_txqueues(struct b43legacy_wldev *dev)
652 {
653 	struct b43legacy_pio *pio;
654 
655 	B43legacy_WARN_ON(!b43legacy_using_pio(dev));
656 	pio = &dev->pio;
657 	pio->queue0->tx_frozen = 1;
658 	pio->queue1->tx_frozen = 1;
659 	pio->queue2->tx_frozen = 1;
660 	pio->queue3->tx_frozen = 1;
661 }
662 
b43legacy_pio_thaw_txqueues(struct b43legacy_wldev * dev)663 void b43legacy_pio_thaw_txqueues(struct b43legacy_wldev *dev)
664 {
665 	struct b43legacy_pio *pio;
666 
667 	B43legacy_WARN_ON(!b43legacy_using_pio(dev));
668 	pio = &dev->pio;
669 	pio->queue0->tx_frozen = 0;
670 	pio->queue1->tx_frozen = 0;
671 	pio->queue2->tx_frozen = 0;
672 	pio->queue3->tx_frozen = 0;
673 	if (!list_empty(&pio->queue0->txqueue))
674 		tasklet_schedule(&pio->queue0->txtask);
675 	if (!list_empty(&pio->queue1->txqueue))
676 		tasklet_schedule(&pio->queue1->txtask);
677 	if (!list_empty(&pio->queue2->txqueue))
678 		tasklet_schedule(&pio->queue2->txtask);
679 	if (!list_empty(&pio->queue3->txqueue))
680 		tasklet_schedule(&pio->queue3->txtask);
681 }
682