1 /*
2 * This file is part of wl1251
3 *
4 * Copyright (c) 1998-2007 Texas Instruments Incorporated
5 * Copyright (C) 2008 Nokia Corporation
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * version 2 as published by the Free Software Foundation.
10 *
11 * This program is distributed in the hope that it will be useful, but
12 * WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
19 * 02110-1301 USA
20 *
21 */
22
23 #include <linux/kernel.h>
24 #include <linux/module.h>
25
26 #include "wl1251.h"
27 #include "reg.h"
28 #include "tx.h"
29 #include "ps.h"
30 #include "io.h"
31 #include "event.h"
32
wl1251_tx_double_buffer_busy(struct wl1251 * wl,u32 data_out_count)33 static bool wl1251_tx_double_buffer_busy(struct wl1251 *wl, u32 data_out_count)
34 {
35 int used, data_in_count;
36
37 data_in_count = wl->data_in_count;
38
39 if (data_in_count < data_out_count)
40 /* data_in_count has wrapped */
41 data_in_count += TX_STATUS_DATA_OUT_COUNT_MASK + 1;
42
43 used = data_in_count - data_out_count;
44
45 WARN_ON(used < 0);
46 WARN_ON(used > DP_TX_PACKET_RING_CHUNK_NUM);
47
48 if (used >= DP_TX_PACKET_RING_CHUNK_NUM)
49 return true;
50 else
51 return false;
52 }
53
wl1251_tx_path_status(struct wl1251 * wl)54 static int wl1251_tx_path_status(struct wl1251 *wl)
55 {
56 u32 status, addr, data_out_count;
57 bool busy;
58
59 addr = wl->data_path->tx_control_addr;
60 status = wl1251_mem_read32(wl, addr);
61 data_out_count = status & TX_STATUS_DATA_OUT_COUNT_MASK;
62 busy = wl1251_tx_double_buffer_busy(wl, data_out_count);
63
64 if (busy)
65 return -EBUSY;
66
67 return 0;
68 }
69
wl1251_tx_id(struct wl1251 * wl,struct sk_buff * skb)70 static int wl1251_tx_id(struct wl1251 *wl, struct sk_buff *skb)
71 {
72 int i;
73
74 for (i = 0; i < FW_TX_CMPLT_BLOCK_SIZE; i++)
75 if (wl->tx_frames[i] == NULL) {
76 wl->tx_frames[i] = skb;
77 return i;
78 }
79
80 return -EBUSY;
81 }
82
wl1251_tx_control(struct tx_double_buffer_desc * tx_hdr,struct ieee80211_tx_info * control,u16 fc)83 static void wl1251_tx_control(struct tx_double_buffer_desc *tx_hdr,
84 struct ieee80211_tx_info *control, u16 fc)
85 {
86 *(u16 *)&tx_hdr->control = 0;
87
88 tx_hdr->control.rate_policy = 0;
89
90 /* 802.11 packets */
91 tx_hdr->control.packet_type = 0;
92
93 /* Also disable retry and ACK policy for injected packets */
94 if ((control->flags & IEEE80211_TX_CTL_NO_ACK) ||
95 (control->flags & IEEE80211_TX_CTL_INJECTED)) {
96 tx_hdr->control.rate_policy = 1;
97 tx_hdr->control.ack_policy = 1;
98 }
99
100 tx_hdr->control.tx_complete = 1;
101
102 if ((fc & IEEE80211_FTYPE_DATA) &&
103 ((fc & IEEE80211_STYPE_QOS_DATA) ||
104 (fc & IEEE80211_STYPE_QOS_NULLFUNC)))
105 tx_hdr->control.qos = 1;
106 }
107
108 /* RSN + MIC = 8 + 8 = 16 bytes (worst case - AES). */
109 #define MAX_MSDU_SECURITY_LENGTH 16
110 #define MAX_MPDU_SECURITY_LENGTH 16
111 #define WLAN_QOS_HDR_LEN 26
112 #define MAX_MPDU_HEADER_AND_SECURITY (MAX_MPDU_SECURITY_LENGTH + \
113 WLAN_QOS_HDR_LEN)
114 #define HW_BLOCK_SIZE 252
wl1251_tx_frag_block_num(struct tx_double_buffer_desc * tx_hdr)115 static void wl1251_tx_frag_block_num(struct tx_double_buffer_desc *tx_hdr)
116 {
117 u16 payload_len, frag_threshold, mem_blocks;
118 u16 num_mpdus, mem_blocks_per_frag;
119
120 frag_threshold = IEEE80211_MAX_FRAG_THRESHOLD;
121 tx_hdr->frag_threshold = cpu_to_le16(frag_threshold);
122
123 payload_len = le16_to_cpu(tx_hdr->length) + MAX_MSDU_SECURITY_LENGTH;
124
125 if (payload_len > frag_threshold) {
126 mem_blocks_per_frag =
127 ((frag_threshold + MAX_MPDU_HEADER_AND_SECURITY) /
128 HW_BLOCK_SIZE) + 1;
129 num_mpdus = payload_len / frag_threshold;
130 mem_blocks = num_mpdus * mem_blocks_per_frag;
131 payload_len -= num_mpdus * frag_threshold;
132 num_mpdus++;
133
134 } else {
135 mem_blocks_per_frag = 0;
136 mem_blocks = 0;
137 num_mpdus = 1;
138 }
139
140 mem_blocks += (payload_len / HW_BLOCK_SIZE) + 1;
141
142 if (num_mpdus > 1)
143 mem_blocks += min(num_mpdus, mem_blocks_per_frag);
144
145 tx_hdr->num_mem_blocks = mem_blocks;
146 }
147
wl1251_tx_fill_hdr(struct wl1251 * wl,struct sk_buff * skb,struct ieee80211_tx_info * control)148 static int wl1251_tx_fill_hdr(struct wl1251 *wl, struct sk_buff *skb,
149 struct ieee80211_tx_info *control)
150 {
151 struct tx_double_buffer_desc *tx_hdr;
152 struct ieee80211_rate *rate;
153 int id;
154 u16 fc;
155
156 if (!skb)
157 return -EINVAL;
158
159 id = wl1251_tx_id(wl, skb);
160 if (id < 0)
161 return id;
162
163 fc = *(u16 *)skb->data;
164 tx_hdr = skb_push(skb, sizeof(*tx_hdr));
165
166 tx_hdr->length = cpu_to_le16(skb->len - sizeof(*tx_hdr));
167 rate = ieee80211_get_tx_rate(wl->hw, control);
168 tx_hdr->rate = cpu_to_le16(rate->hw_value);
169 tx_hdr->expiry_time = cpu_to_le32(1 << 16);
170 tx_hdr->id = id;
171
172 tx_hdr->xmit_queue = wl1251_tx_get_queue(skb_get_queue_mapping(skb));
173
174 wl1251_tx_control(tx_hdr, control, fc);
175 wl1251_tx_frag_block_num(tx_hdr);
176
177 return 0;
178 }
179
180 /* We copy the packet to the target */
wl1251_tx_send_packet(struct wl1251 * wl,struct sk_buff * skb,struct ieee80211_tx_info * control)181 static int wl1251_tx_send_packet(struct wl1251 *wl, struct sk_buff *skb,
182 struct ieee80211_tx_info *control)
183 {
184 struct tx_double_buffer_desc *tx_hdr;
185 int len;
186 u32 addr;
187
188 if (!skb)
189 return -EINVAL;
190
191 tx_hdr = (struct tx_double_buffer_desc *) skb->data;
192
193 if (control->control.hw_key &&
194 control->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP) {
195 int hdrlen;
196 __le16 fc;
197 u16 length;
198 u8 *pos;
199
200 fc = *(__le16 *)(skb->data + sizeof(*tx_hdr));
201 length = le16_to_cpu(tx_hdr->length) + WL1251_TKIP_IV_SPACE;
202 tx_hdr->length = cpu_to_le16(length);
203
204 hdrlen = ieee80211_hdrlen(fc);
205
206 pos = skb_push(skb, WL1251_TKIP_IV_SPACE);
207 memmove(pos, pos + WL1251_TKIP_IV_SPACE,
208 sizeof(*tx_hdr) + hdrlen);
209 }
210
211 /* Revisit. This is a workaround for getting non-aligned packets.
212 This happens at least with EAPOL packets from the user space.
213 Our DMA requires packets to be aligned on a 4-byte boundary.
214 */
215 if (unlikely((long)skb->data & 0x03)) {
216 int offset = (4 - (long)skb->data) & 0x03;
217 wl1251_debug(DEBUG_TX, "skb offset %d", offset);
218
219 /* check whether the current skb can be used */
220 if (skb_cloned(skb) || (skb_tailroom(skb) < offset)) {
221 struct sk_buff *newskb = skb_copy_expand(skb, 0, 3,
222 GFP_KERNEL);
223
224 if (unlikely(newskb == NULL))
225 return -EINVAL;
226
227 tx_hdr = (struct tx_double_buffer_desc *) newskb->data;
228
229 dev_kfree_skb_any(skb);
230 wl->tx_frames[tx_hdr->id] = skb = newskb;
231
232 offset = (4 - (long)skb->data) & 0x03;
233 wl1251_debug(DEBUG_TX, "new skb offset %d", offset);
234 }
235
236 /* align the buffer on a 4-byte boundary */
237 if (offset) {
238 unsigned char *src = skb->data;
239 skb_reserve(skb, offset);
240 memmove(skb->data, src, skb->len);
241 tx_hdr = (struct tx_double_buffer_desc *) skb->data;
242 }
243 }
244
245 /* Our skb->data at this point includes the HW header */
246 len = WL1251_TX_ALIGN(skb->len);
247
248 if (wl->data_in_count & 0x1)
249 addr = wl->data_path->tx_packet_ring_addr +
250 wl->data_path->tx_packet_ring_chunk_size;
251 else
252 addr = wl->data_path->tx_packet_ring_addr;
253
254 wl1251_mem_write(wl, addr, skb->data, len);
255
256 wl1251_debug(DEBUG_TX, "tx id %u skb 0x%p payload %u rate 0x%x "
257 "queue %d", tx_hdr->id, skb, tx_hdr->length,
258 tx_hdr->rate, tx_hdr->xmit_queue);
259
260 return 0;
261 }
262
wl1251_tx_trigger(struct wl1251 * wl)263 static void wl1251_tx_trigger(struct wl1251 *wl)
264 {
265 u32 data, addr;
266
267 if (wl->data_in_count & 0x1) {
268 addr = ACX_REG_INTERRUPT_TRIG_H;
269 data = INTR_TRIG_TX_PROC1;
270 } else {
271 addr = ACX_REG_INTERRUPT_TRIG;
272 data = INTR_TRIG_TX_PROC0;
273 }
274
275 wl1251_reg_write32(wl, addr, data);
276
277 /* Bumping data in */
278 wl->data_in_count = (wl->data_in_count + 1) &
279 TX_STATUS_DATA_OUT_COUNT_MASK;
280 }
281
enable_tx_for_packet_injection(struct wl1251 * wl)282 static void enable_tx_for_packet_injection(struct wl1251 *wl)
283 {
284 int ret;
285
286 ret = wl1251_cmd_join(wl, BSS_TYPE_STA_BSS, wl->channel,
287 wl->beacon_int, wl->dtim_period);
288 if (ret < 0) {
289 wl1251_warning("join failed");
290 return;
291 }
292
293 ret = wl1251_event_wait(wl, JOIN_EVENT_COMPLETE_ID, 100);
294 if (ret < 0) {
295 wl1251_warning("join timeout");
296 return;
297 }
298
299 wl->joined = true;
300 }
301
302 /* caller must hold wl->mutex */
wl1251_tx_frame(struct wl1251 * wl,struct sk_buff * skb)303 static int wl1251_tx_frame(struct wl1251 *wl, struct sk_buff *skb)
304 {
305 struct ieee80211_tx_info *info;
306 int ret = 0;
307 u8 idx;
308
309 info = IEEE80211_SKB_CB(skb);
310
311 if (info->control.hw_key) {
312 if (unlikely(wl->monitor_present))
313 return -EINVAL;
314
315 idx = info->control.hw_key->hw_key_idx;
316 if (unlikely(wl->default_key != idx)) {
317 ret = wl1251_acx_default_key(wl, idx);
318 if (ret < 0)
319 return ret;
320 }
321 }
322
323 /* Enable tx path in monitor mode for packet injection */
324 if ((wl->vif == NULL) && !wl->joined)
325 enable_tx_for_packet_injection(wl);
326
327 ret = wl1251_tx_path_status(wl);
328 if (ret < 0)
329 return ret;
330
331 ret = wl1251_tx_fill_hdr(wl, skb, info);
332 if (ret < 0)
333 return ret;
334
335 ret = wl1251_tx_send_packet(wl, skb, info);
336 if (ret < 0)
337 return ret;
338
339 wl1251_tx_trigger(wl);
340
341 return ret;
342 }
343
wl1251_tx_work(struct work_struct * work)344 void wl1251_tx_work(struct work_struct *work)
345 {
346 struct wl1251 *wl = container_of(work, struct wl1251, tx_work);
347 struct sk_buff *skb;
348 bool woken_up = false;
349 int ret;
350
351 mutex_lock(&wl->mutex);
352
353 if (unlikely(wl->state == WL1251_STATE_OFF))
354 goto out;
355
356 while ((skb = skb_dequeue(&wl->tx_queue))) {
357 if (!woken_up) {
358 ret = wl1251_ps_elp_wakeup(wl);
359 if (ret < 0)
360 goto out;
361 woken_up = true;
362 }
363
364 ret = wl1251_tx_frame(wl, skb);
365 if (ret == -EBUSY) {
366 skb_queue_head(&wl->tx_queue, skb);
367 goto out;
368 } else if (ret < 0) {
369 dev_kfree_skb(skb);
370 goto out;
371 }
372 }
373
374 out:
375 if (woken_up)
376 wl1251_ps_elp_sleep(wl);
377
378 mutex_unlock(&wl->mutex);
379 }
380
wl1251_tx_parse_status(u8 status)381 static const char *wl1251_tx_parse_status(u8 status)
382 {
383 /* 8 bit status field, one character per bit plus null */
384 static char buf[9];
385 int i = 0;
386
387 memset(buf, 0, sizeof(buf));
388
389 if (status & TX_DMA_ERROR)
390 buf[i++] = 'm';
391 if (status & TX_DISABLED)
392 buf[i++] = 'd';
393 if (status & TX_RETRY_EXCEEDED)
394 buf[i++] = 'r';
395 if (status & TX_TIMEOUT)
396 buf[i++] = 't';
397 if (status & TX_KEY_NOT_FOUND)
398 buf[i++] = 'k';
399 if (status & TX_ENCRYPT_FAIL)
400 buf[i++] = 'e';
401 if (status & TX_UNAVAILABLE_PRIORITY)
402 buf[i++] = 'p';
403
404 /* bit 0 is unused apparently */
405
406 return buf;
407 }
408
wl1251_tx_packet_cb(struct wl1251 * wl,struct tx_result * result)409 static void wl1251_tx_packet_cb(struct wl1251 *wl,
410 struct tx_result *result)
411 {
412 struct ieee80211_tx_info *info;
413 struct sk_buff *skb;
414 int hdrlen;
415 u8 *frame;
416
417 skb = wl->tx_frames[result->id];
418 if (skb == NULL) {
419 wl1251_error("SKB for packet %d is NULL", result->id);
420 return;
421 }
422
423 info = IEEE80211_SKB_CB(skb);
424
425 if (!(info->flags & IEEE80211_TX_CTL_NO_ACK) &&
426 !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
427 (result->status == TX_SUCCESS))
428 info->flags |= IEEE80211_TX_STAT_ACK;
429
430 info->status.rates[0].count = result->ack_failures + 1;
431 wl->stats.retry_count += result->ack_failures;
432
433 /*
434 * We have to remove our private TX header before pushing
435 * the skb back to mac80211.
436 */
437 frame = skb_pull(skb, sizeof(struct tx_double_buffer_desc));
438 if (info->control.hw_key &&
439 info->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP) {
440 hdrlen = ieee80211_get_hdrlen_from_skb(skb);
441 memmove(frame + WL1251_TKIP_IV_SPACE, frame, hdrlen);
442 skb_pull(skb, WL1251_TKIP_IV_SPACE);
443 }
444
445 wl1251_debug(DEBUG_TX, "tx status id %u skb 0x%p failures %u rate 0x%x"
446 " status 0x%x (%s)",
447 result->id, skb, result->ack_failures, result->rate,
448 result->status, wl1251_tx_parse_status(result->status));
449
450
451 ieee80211_tx_status(wl->hw, skb);
452
453 wl->tx_frames[result->id] = NULL;
454 }
455
456 /* Called upon reception of a TX complete interrupt */
wl1251_tx_complete(struct wl1251 * wl)457 void wl1251_tx_complete(struct wl1251 *wl)
458 {
459 int i, result_index, num_complete = 0, queue_len;
460 struct tx_result result[FW_TX_CMPLT_BLOCK_SIZE], *result_ptr;
461 unsigned long flags;
462
463 if (unlikely(wl->state != WL1251_STATE_ON))
464 return;
465
466 /* First we read the result */
467 wl1251_mem_read(wl, wl->data_path->tx_complete_addr,
468 result, sizeof(result));
469
470 result_index = wl->next_tx_complete;
471
472 for (i = 0; i < ARRAY_SIZE(result); i++) {
473 result_ptr = &result[result_index];
474
475 if (result_ptr->done_1 == 1 &&
476 result_ptr->done_2 == 1) {
477 wl1251_tx_packet_cb(wl, result_ptr);
478
479 result_ptr->done_1 = 0;
480 result_ptr->done_2 = 0;
481
482 result_index = (result_index + 1) &
483 (FW_TX_CMPLT_BLOCK_SIZE - 1);
484 num_complete++;
485 } else {
486 break;
487 }
488 }
489
490 queue_len = skb_queue_len(&wl->tx_queue);
491
492 if ((num_complete > 0) && (queue_len > 0)) {
493 /* firmware buffer has space, reschedule tx_work */
494 wl1251_debug(DEBUG_TX, "tx_complete: reschedule tx_work");
495 ieee80211_queue_work(wl->hw, &wl->tx_work);
496 }
497
498 if (wl->tx_queue_stopped &&
499 queue_len <= WL1251_TX_QUEUE_LOW_WATERMARK) {
500 /* tx_queue has space, restart queues */
501 wl1251_debug(DEBUG_TX, "tx_complete: waking queues");
502 spin_lock_irqsave(&wl->wl_lock, flags);
503 ieee80211_wake_queues(wl->hw);
504 wl->tx_queue_stopped = false;
505 spin_unlock_irqrestore(&wl->wl_lock, flags);
506 }
507
508 /* Every completed frame needs to be acknowledged */
509 if (num_complete) {
510 /*
511 * If we've wrapped, we have to clear
512 * the results in 2 steps.
513 */
514 if (result_index > wl->next_tx_complete) {
515 /* Only 1 write is needed */
516 wl1251_mem_write(wl,
517 wl->data_path->tx_complete_addr +
518 (wl->next_tx_complete *
519 sizeof(struct tx_result)),
520 &result[wl->next_tx_complete],
521 num_complete *
522 sizeof(struct tx_result));
523
524
525 } else if (result_index < wl->next_tx_complete) {
526 /* 2 writes are needed */
527 wl1251_mem_write(wl,
528 wl->data_path->tx_complete_addr +
529 (wl->next_tx_complete *
530 sizeof(struct tx_result)),
531 &result[wl->next_tx_complete],
532 (FW_TX_CMPLT_BLOCK_SIZE -
533 wl->next_tx_complete) *
534 sizeof(struct tx_result));
535
536 wl1251_mem_write(wl,
537 wl->data_path->tx_complete_addr,
538 result,
539 (num_complete -
540 FW_TX_CMPLT_BLOCK_SIZE +
541 wl->next_tx_complete) *
542 sizeof(struct tx_result));
543
544 } else {
545 /* We have to write the whole array */
546 wl1251_mem_write(wl,
547 wl->data_path->tx_complete_addr,
548 result,
549 FW_TX_CMPLT_BLOCK_SIZE *
550 sizeof(struct tx_result));
551 }
552
553 }
554
555 wl->next_tx_complete = result_index;
556 }
557
558 /* caller must hold wl->mutex */
wl1251_tx_flush(struct wl1251 * wl)559 void wl1251_tx_flush(struct wl1251 *wl)
560 {
561 int i;
562 struct sk_buff *skb;
563 struct ieee80211_tx_info *info;
564
565 /* TX failure */
566 /* control->flags = 0; FIXME */
567
568 while ((skb = skb_dequeue(&wl->tx_queue))) {
569 info = IEEE80211_SKB_CB(skb);
570
571 wl1251_debug(DEBUG_TX, "flushing skb 0x%p", skb);
572
573 if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS))
574 continue;
575
576 ieee80211_tx_status(wl->hw, skb);
577 }
578
579 for (i = 0; i < FW_TX_CMPLT_BLOCK_SIZE; i++)
580 if (wl->tx_frames[i] != NULL) {
581 skb = wl->tx_frames[i];
582 info = IEEE80211_SKB_CB(skb);
583
584 if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS))
585 continue;
586
587 ieee80211_tx_status(wl->hw, skb);
588 wl->tx_frames[i] = NULL;
589 }
590 }
591
