tx.c revision 7edebf56ca424484b9e0e51a6188c93c7fdd3a41
1/*
2 * This file is part of wl1271
3 *
4 * Copyright (C) 2009 Nokia Corporation
5 *
6 * Contact: Luciano Coelho <luciano.coelho@nokia.com>
7 *
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * version 2 as published by the Free Software Foundation.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
20 * 02110-1301 USA
21 *
22 */
23
24#include <linux/kernel.h>
25#include <linux/module.h>
26#include <linux/etherdevice.h>
27
28#include "wl12xx.h"
29#include "io.h"
30#include "reg.h"
31#include "ps.h"
32#include "tx.h"
33#include "event.h"
34
35static int wl1271_set_default_wep_key(struct wl1271 *wl,
36				      struct wl12xx_vif *wlvif, u8 id)
37{
38	int ret;
39	bool is_ap = (wlvif->bss_type == BSS_TYPE_AP_BSS);
40
41	if (is_ap)
42		ret = wl12xx_cmd_set_default_wep_key(wl, id,
43						     wl->ap_bcast_hlid);
44	else
45		ret = wl12xx_cmd_set_default_wep_key(wl, id, wl->sta_hlid);
46
47	if (ret < 0)
48		return ret;
49
50	wl1271_debug(DEBUG_CRYPT, "default wep key idx: %d", (int)id);
51	return 0;
52}
53
54static int wl1271_alloc_tx_id(struct wl1271 *wl, struct sk_buff *skb)
55{
56	int id;
57
58	id = find_first_zero_bit(wl->tx_frames_map, ACX_TX_DESCRIPTORS);
59	if (id >= ACX_TX_DESCRIPTORS)
60		return -EBUSY;
61
62	__set_bit(id, wl->tx_frames_map);
63	wl->tx_frames[id] = skb;
64	wl->tx_frames_cnt++;
65	return id;
66}
67
68static void wl1271_free_tx_id(struct wl1271 *wl, int id)
69{
70	if (__test_and_clear_bit(id, wl->tx_frames_map)) {
71		if (unlikely(wl->tx_frames_cnt == ACX_TX_DESCRIPTORS))
72			clear_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags);
73
74		wl->tx_frames[id] = NULL;
75		wl->tx_frames_cnt--;
76	}
77}
78
79static int wl1271_tx_update_filters(struct wl1271 *wl,
80				    struct wl12xx_vif *wlvif,
81				    struct sk_buff *skb)
82{
83	struct ieee80211_hdr *hdr;
84	int ret;
85
86	hdr = (struct ieee80211_hdr *)skb->data;
87
88	/*
89	 * stop bssid-based filtering before transmitting authentication
90	 * requests. this way the hw will never drop authentication
91	 * responses coming from BSSIDs it isn't familiar with (e.g. on
92	 * roaming)
93	 */
94	if (!ieee80211_is_auth(hdr->frame_control))
95		return 0;
96
97	if (wl->dev_hlid != WL12XX_INVALID_LINK_ID)
98		goto out;
99
100	wl1271_debug(DEBUG_CMD, "starting device role for roaming");
101	ret = wl12xx_cmd_role_start_dev(wl, wlvif);
102	if (ret < 0)
103		goto out;
104
105	ret = wl12xx_roc(wl, wlvif->dev_role_id);
106	if (ret < 0)
107		goto out;
108out:
109	return 0;
110}
111
112static void wl1271_tx_ap_update_inconnection_sta(struct wl1271 *wl,
113						 struct sk_buff *skb)
114{
115	struct ieee80211_hdr *hdr;
116
117	/*
118	 * add the station to the known list before transmitting the
119	 * authentication response. this way it won't get de-authed by FW
120	 * when transmitting too soon.
121	 */
122	hdr = (struct ieee80211_hdr *)(skb->data +
123				       sizeof(struct wl1271_tx_hw_descr));
124	if (ieee80211_is_auth(hdr->frame_control))
125		wl1271_acx_set_inconnection_sta(wl, hdr->addr1);
126}
127
128static void wl1271_tx_regulate_link(struct wl1271 *wl, u8 hlid)
129{
130	bool fw_ps, single_sta;
131	u8 tx_pkts;
132
133	/* only regulate station links */
134	if (hlid < WL1271_AP_STA_HLID_START)
135		return;
136
137	if (WARN_ON(!wl1271_is_active_sta(wl, hlid)))
138	    return;
139
140	fw_ps = test_bit(hlid, (unsigned long *)&wl->ap_fw_ps_map);
141	tx_pkts = wl->links[hlid].allocated_pkts;
142	single_sta = (wl->active_sta_count == 1);
143
144	/*
145	 * if in FW PS and there is enough data in FW we can put the link
146	 * into high-level PS and clean out its TX queues.
147	 * Make an exception if this is the only connected station. In this
148	 * case FW-memory congestion is not a problem.
149	 */
150	if (!single_sta && fw_ps && tx_pkts >= WL1271_PS_STA_MAX_PACKETS)
151		wl1271_ps_link_start(wl, hlid, true);
152}
153
154bool wl12xx_is_dummy_packet(struct wl1271 *wl, struct sk_buff *skb)
155{
156	return wl->dummy_packet == skb;
157}
158
159u8 wl12xx_tx_get_hlid_ap(struct wl1271 *wl, struct sk_buff *skb)
160{
161	struct ieee80211_tx_info *control = IEEE80211_SKB_CB(skb);
162
163	if (control->control.sta) {
164		struct wl1271_station *wl_sta;
165
166		wl_sta = (struct wl1271_station *)
167				control->control.sta->drv_priv;
168		return wl_sta->hlid;
169	} else {
170		struct ieee80211_hdr *hdr;
171
172		if (!test_bit(WL1271_FLAG_AP_STARTED, &wl->flags))
173			return wl->system_hlid;
174
175		hdr = (struct ieee80211_hdr *)skb->data;
176		if (ieee80211_is_mgmt(hdr->frame_control))
177			return wl->ap_global_hlid;
178		else
179			return wl->ap_bcast_hlid;
180	}
181}
182
183static u8 wl1271_tx_get_hlid(struct wl1271 *wl, struct ieee80211_vif *vif,
184			     struct sk_buff *skb)
185{
186	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)skb->data;
187	struct wl12xx_vif *wlvif = wl12xx_vif_to_data(vif);
188
189
190	if (wl12xx_is_dummy_packet(wl, skb))
191		return wl->system_hlid;
192
193	if (wlvif->bss_type == BSS_TYPE_AP_BSS)
194		return wl12xx_tx_get_hlid_ap(wl, skb);
195
196	wl1271_tx_update_filters(wl, wlvif, skb);
197
198	if ((test_bit(WL1271_FLAG_STA_ASSOCIATED, &wl->flags) ||
199	     test_bit(WL1271_FLAG_IBSS_JOINED, &wl->flags)) &&
200	    !ieee80211_is_auth(hdr->frame_control) &&
201	    !ieee80211_is_assoc_req(hdr->frame_control))
202		return wl->sta_hlid;
203	else
204		return wl->dev_hlid;
205}
206
207static unsigned int wl12xx_calc_packet_alignment(struct wl1271 *wl,
208						unsigned int packet_length)
209{
210	if (wl->quirks & WL12XX_QUIRK_BLOCKSIZE_ALIGNMENT)
211		return ALIGN(packet_length, WL12XX_BUS_BLOCK_SIZE);
212	else
213		return ALIGN(packet_length, WL1271_TX_ALIGN_TO);
214}
215
216static int wl1271_tx_allocate(struct wl1271 *wl, struct ieee80211_vif *vif,
217			      struct sk_buff *skb, u32 extra, u32 buf_offset,
218			      u8 hlid)
219{
220	struct wl12xx_vif *wlvif = wl12xx_vif_to_data(vif);
221	struct wl1271_tx_hw_descr *desc;
222	u32 total_len = skb->len + sizeof(struct wl1271_tx_hw_descr) + extra;
223	u32 len;
224	u32 total_blocks;
225	int id, ret = -EBUSY, ac;
226	u32 spare_blocks = wl->tx_spare_blocks;
227
228	if (buf_offset + total_len > WL1271_AGGR_BUFFER_SIZE)
229		return -EAGAIN;
230
231	/* allocate free identifier for the packet */
232	id = wl1271_alloc_tx_id(wl, skb);
233	if (id < 0)
234		return id;
235
236	/* approximate the number of blocks required for this packet
237	   in the firmware */
238	len = wl12xx_calc_packet_alignment(wl, total_len);
239
240	/* in case of a dummy packet, use default amount of spare mem blocks */
241	if (unlikely(wl12xx_is_dummy_packet(wl, skb)))
242		spare_blocks = TX_HW_BLOCK_SPARE_DEFAULT;
243
244	total_blocks = (len + TX_HW_BLOCK_SIZE - 1) / TX_HW_BLOCK_SIZE +
245		spare_blocks;
246
247	if (total_blocks <= wl->tx_blocks_available) {
248		desc = (struct wl1271_tx_hw_descr *)skb_push(
249			skb, total_len - skb->len);
250
251		/* HW descriptor fields change between wl127x and wl128x */
252		if (wl->chip.id == CHIP_ID_1283_PG20) {
253			desc->wl128x_mem.total_mem_blocks = total_blocks;
254		} else {
255			desc->wl127x_mem.extra_blocks = spare_blocks;
256			desc->wl127x_mem.total_mem_blocks = total_blocks;
257		}
258
259		desc->id = id;
260
261		wl->tx_blocks_available -= total_blocks;
262		wl->tx_allocated_blocks += total_blocks;
263
264		ac = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
265		wl->tx_allocated_pkts[ac]++;
266
267		if (wlvif->bss_type == BSS_TYPE_AP_BSS &&
268		    hlid >= WL1271_AP_STA_HLID_START)
269			wl->links[hlid].allocated_pkts++;
270
271		ret = 0;
272
273		wl1271_debug(DEBUG_TX,
274			     "tx_allocate: size: %d, blocks: %d, id: %d",
275			     total_len, total_blocks, id);
276	} else {
277		wl1271_free_tx_id(wl, id);
278	}
279
280	return ret;
281}
282
283static void wl1271_tx_fill_hdr(struct wl1271 *wl, struct ieee80211_vif *vif,
284			       struct sk_buff *skb, u32 extra,
285			       struct ieee80211_tx_info *control, u8 hlid)
286{
287	struct wl12xx_vif *wlvif = wl12xx_vif_to_data(vif);
288	struct timespec ts;
289	struct wl1271_tx_hw_descr *desc;
290	int aligned_len, ac, rate_idx;
291	s64 hosttime;
292	u16 tx_attr;
293
294	desc = (struct wl1271_tx_hw_descr *) skb->data;
295
296	/* relocate space for security header */
297	if (extra) {
298		void *framestart = skb->data + sizeof(*desc);
299		u16 fc = *(u16 *)(framestart + extra);
300		int hdrlen = ieee80211_hdrlen(cpu_to_le16(fc));
301		memmove(framestart, framestart + extra, hdrlen);
302	}
303
304	/* configure packet life time */
305	getnstimeofday(&ts);
306	hosttime = (timespec_to_ns(&ts) >> 10);
307	desc->start_time = cpu_to_le32(hosttime - wl->time_offset);
308
309	if (wlvif->bss_type != BSS_TYPE_AP_BSS)
310		desc->life_time = cpu_to_le16(TX_HW_MGMT_PKT_LIFETIME_TU);
311	else
312		desc->life_time = cpu_to_le16(TX_HW_AP_MODE_PKT_LIFETIME_TU);
313
314	/* queue */
315	ac = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
316	desc->tid = skb->priority;
317
318	if (wl12xx_is_dummy_packet(wl, skb)) {
319		/*
320		 * FW expects the dummy packet to have an invalid session id -
321		 * any session id that is different than the one set in the join
322		 */
323		tx_attr = ((~wl->session_counter) <<
324			   TX_HW_ATTR_OFST_SESSION_COUNTER) &
325			   TX_HW_ATTR_SESSION_COUNTER;
326
327		tx_attr |= TX_HW_ATTR_TX_DUMMY_REQ;
328	} else {
329		/* configure the tx attributes */
330		tx_attr =
331			wl->session_counter << TX_HW_ATTR_OFST_SESSION_COUNTER;
332	}
333
334	desc->hlid = hlid;
335	if (wlvif->bss_type != BSS_TYPE_AP_BSS) {
336		/* if the packets are destined for AP (have a STA entry)
337		   send them with AP rate policies, otherwise use default
338		   basic rates */
339		if (control->control.sta)
340			rate_idx = ACX_TX_AP_FULL_RATE;
341		else
342			rate_idx = ACX_TX_BASIC_RATE;
343	} else {
344		if (hlid == wl->ap_global_hlid)
345			rate_idx = ACX_TX_AP_MODE_MGMT_RATE;
346		else if (hlid == wl->ap_bcast_hlid)
347			rate_idx = ACX_TX_AP_MODE_BCST_RATE;
348		else
349			rate_idx = ac;
350	}
351
352	tx_attr |= rate_idx << TX_HW_ATTR_OFST_RATE_POLICY;
353	desc->reserved = 0;
354
355	aligned_len = wl12xx_calc_packet_alignment(wl, skb->len);
356
357	if (wl->chip.id == CHIP_ID_1283_PG20) {
358		desc->wl128x_mem.extra_bytes = aligned_len - skb->len;
359		desc->length = cpu_to_le16(aligned_len >> 2);
360
361		wl1271_debug(DEBUG_TX, "tx_fill_hdr: hlid: %d "
362			     "tx_attr: 0x%x len: %d life: %d mem: %d",
363			     desc->hlid, tx_attr,
364			     le16_to_cpu(desc->length),
365			     le16_to_cpu(desc->life_time),
366			     desc->wl128x_mem.total_mem_blocks);
367	} else {
368		int pad;
369
370		/* Store the aligned length in terms of words */
371		desc->length = cpu_to_le16(aligned_len >> 2);
372
373		/* calculate number of padding bytes */
374		pad = aligned_len - skb->len;
375		tx_attr |= pad << TX_HW_ATTR_OFST_LAST_WORD_PAD;
376
377		wl1271_debug(DEBUG_TX, "tx_fill_hdr: pad: %d hlid: %d "
378			     "tx_attr: 0x%x len: %d life: %d mem: %d", pad,
379			     desc->hlid, tx_attr,
380			     le16_to_cpu(desc->length),
381			     le16_to_cpu(desc->life_time),
382			     desc->wl127x_mem.total_mem_blocks);
383	}
384
385	desc->tx_attr = cpu_to_le16(tx_attr);
386}
387
388/* caller must hold wl->mutex */
389static int wl1271_prepare_tx_frame(struct wl1271 *wl, struct sk_buff *skb,
390							u32 buf_offset)
391{
392	struct ieee80211_tx_info *info;
393	struct ieee80211_vif *vif;
394	struct wl12xx_vif *wlvif;
395	u32 extra = 0;
396	int ret = 0;
397	u32 total_len;
398	u8 hlid;
399	bool is_dummy;
400
401	if (!skb)
402		return -EINVAL;
403
404	info = IEEE80211_SKB_CB(skb);
405
406	/* TODO: handle dummy packets on multi-vifs */
407	is_dummy = wl12xx_is_dummy_packet(wl, skb);
408	if (is_dummy)
409		info->control.vif = wl->vif;
410
411	vif = info->control.vif;
412	wlvif = wl12xx_vif_to_data(vif);
413
414	if (info->control.hw_key &&
415	    info->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP)
416		extra = WL1271_TKIP_IV_SPACE;
417
418	if (info->control.hw_key) {
419		bool is_wep;
420		u8 idx = info->control.hw_key->hw_key_idx;
421		u32 cipher = info->control.hw_key->cipher;
422
423		is_wep = (cipher == WLAN_CIPHER_SUITE_WEP40) ||
424			 (cipher == WLAN_CIPHER_SUITE_WEP104);
425
426		if (unlikely(is_wep && wl->default_key != idx)) {
427			ret = wl1271_set_default_wep_key(wl, wlvif, idx);
428			if (ret < 0)
429				return ret;
430			wl->default_key = idx;
431		}
432	}
433	hlid = wl1271_tx_get_hlid(wl, vif, skb);
434	if (hlid == WL12XX_INVALID_LINK_ID) {
435		wl1271_error("invalid hlid. dropping skb 0x%p", skb);
436		return -EINVAL;
437	}
438
439	ret = wl1271_tx_allocate(wl, vif, skb, extra, buf_offset, hlid);
440	if (ret < 0)
441		return ret;
442
443	wl1271_tx_fill_hdr(wl, vif, skb, extra, info, hlid);
444
445	if (wlvif->bss_type == BSS_TYPE_AP_BSS && !is_dummy) {
446		wl1271_tx_ap_update_inconnection_sta(wl, skb);
447		wl1271_tx_regulate_link(wl, hlid);
448	}
449
450	/*
451	 * The length of each packet is stored in terms of
452	 * words. Thus, we must pad the skb data to make sure its
453	 * length is aligned.  The number of padding bytes is computed
454	 * and set in wl1271_tx_fill_hdr.
455	 * In special cases, we want to align to a specific block size
456	 * (eg. for wl128x with SDIO we align to 256).
457	 */
458	total_len = wl12xx_calc_packet_alignment(wl, skb->len);
459
460	memcpy(wl->aggr_buf + buf_offset, skb->data, skb->len);
461	memset(wl->aggr_buf + buf_offset + skb->len, 0, total_len - skb->len);
462
463	/* Revert side effects in the dummy packet skb, so it can be reused */
464	if (is_dummy)
465		skb_pull(skb, sizeof(struct wl1271_tx_hw_descr));
466
467	return total_len;
468}
469
470u32 wl1271_tx_enabled_rates_get(struct wl1271 *wl, u32 rate_set,
471				enum ieee80211_band rate_band)
472{
473	struct ieee80211_supported_band *band;
474	u32 enabled_rates = 0;
475	int bit;
476
477	band = wl->hw->wiphy->bands[rate_band];
478	for (bit = 0; bit < band->n_bitrates; bit++) {
479		if (rate_set & 0x1)
480			enabled_rates |= band->bitrates[bit].hw_value;
481		rate_set >>= 1;
482	}
483
484	/* MCS rates indication are on bits 16 - 23 */
485	rate_set >>= HW_HT_RATES_OFFSET - band->n_bitrates;
486
487	for (bit = 0; bit < 8; bit++) {
488		if (rate_set & 0x1)
489			enabled_rates |= (CONF_HW_BIT_RATE_MCS_0 << bit);
490		rate_set >>= 1;
491	}
492
493	return enabled_rates;
494}
495
496void wl1271_handle_tx_low_watermark(struct wl1271 *wl)
497{
498	unsigned long flags;
499	int i;
500
501	for (i = 0; i < NUM_TX_QUEUES; i++) {
502		if (test_bit(i, &wl->stopped_queues_map) &&
503		    wl->tx_queue_count[i] <= WL1271_TX_QUEUE_LOW_WATERMARK) {
504			/* firmware buffer has space, restart queues */
505			spin_lock_irqsave(&wl->wl_lock, flags);
506			ieee80211_wake_queue(wl->hw,
507					     wl1271_tx_get_mac80211_queue(i));
508			clear_bit(i, &wl->stopped_queues_map);
509			spin_unlock_irqrestore(&wl->wl_lock, flags);
510		}
511	}
512}
513
514static struct sk_buff_head *wl1271_select_queue(struct wl1271 *wl,
515						struct sk_buff_head *queues)
516{
517	int i, q = -1, ac;
518	u32 min_pkts = 0xffffffff;
519
520	/*
521	 * Find a non-empty ac where:
522	 * 1. There are packets to transmit
523	 * 2. The FW has the least allocated blocks
524	 *
525	 * We prioritize the ACs according to VO>VI>BE>BK
526	 */
527	for (i = 0; i < NUM_TX_QUEUES; i++) {
528		ac = wl1271_tx_get_queue(i);
529		if (!skb_queue_empty(&queues[ac]) &&
530		    (wl->tx_allocated_pkts[ac] < min_pkts)) {
531			q = ac;
532			min_pkts = wl->tx_allocated_pkts[q];
533		}
534	}
535
536	if (q == -1)
537		return NULL;
538
539	return &queues[q];
540}
541
542static struct sk_buff *wl1271_sta_skb_dequeue(struct wl1271 *wl)
543{
544	struct sk_buff *skb = NULL;
545	unsigned long flags;
546	struct sk_buff_head *queue;
547
548	queue = wl1271_select_queue(wl, wl->tx_queue);
549	if (!queue)
550		goto out;
551
552	skb = skb_dequeue(queue);
553
554out:
555	if (skb) {
556		int q = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
557		spin_lock_irqsave(&wl->wl_lock, flags);
558		wl->tx_queue_count[q]--;
559		spin_unlock_irqrestore(&wl->wl_lock, flags);
560	}
561
562	return skb;
563}
564
565static struct sk_buff *wl1271_ap_skb_dequeue(struct wl1271 *wl)
566{
567	struct sk_buff *skb = NULL;
568	unsigned long flags;
569	int i, h, start_hlid;
570	struct sk_buff_head *queue;
571
572	/* start from the link after the last one */
573	start_hlid = (wl->last_tx_hlid + 1) % AP_MAX_LINKS;
574
575	/* dequeue according to AC, round robin on each link */
576	for (i = 0; i < AP_MAX_LINKS; i++) {
577		h = (start_hlid + i) % AP_MAX_LINKS;
578
579		/* only consider connected stations */
580		if (h >= WL1271_AP_STA_HLID_START &&
581		    !test_bit(h - WL1271_AP_STA_HLID_START, wl->ap_hlid_map))
582			continue;
583
584		queue = wl1271_select_queue(wl, wl->links[h].tx_queue);
585		if (!queue)
586			continue;
587
588		skb = skb_dequeue(queue);
589		if (skb)
590			break;
591	}
592
593	if (skb) {
594		int q = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
595		wl->last_tx_hlid = h;
596		spin_lock_irqsave(&wl->wl_lock, flags);
597		wl->tx_queue_count[q]--;
598		spin_unlock_irqrestore(&wl->wl_lock, flags);
599	} else {
600		wl->last_tx_hlid = 0;
601	}
602
603	return skb;
604}
605
606static struct sk_buff *wl1271_skb_dequeue(struct wl1271 *wl,
607					  struct wl12xx_vif *wlvif)
608{
609	unsigned long flags;
610	struct sk_buff *skb = NULL;
611
612	if (wlvif->bss_type == BSS_TYPE_AP_BSS)
613		skb = wl1271_ap_skb_dequeue(wl);
614	else
615		skb = wl1271_sta_skb_dequeue(wl);
616
617	if (!skb &&
618	    test_and_clear_bit(WL1271_FLAG_DUMMY_PACKET_PENDING, &wl->flags)) {
619		int q;
620
621		skb = wl->dummy_packet;
622		q = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
623		spin_lock_irqsave(&wl->wl_lock, flags);
624		wl->tx_queue_count[q]--;
625		spin_unlock_irqrestore(&wl->wl_lock, flags);
626	}
627
628	return skb;
629}
630
631static void wl1271_skb_queue_head(struct wl1271 *wl, struct ieee80211_vif *vif,
632				  struct sk_buff *skb)
633{
634	struct wl12xx_vif *wlvif = wl12xx_vif_to_data(vif);
635	unsigned long flags;
636	int q = wl1271_tx_get_queue(skb_get_queue_mapping(skb));
637
638	if (wl12xx_is_dummy_packet(wl, skb)) {
639		set_bit(WL1271_FLAG_DUMMY_PACKET_PENDING, &wl->flags);
640	} else if (wlvif->bss_type == BSS_TYPE_AP_BSS) {
641		u8 hlid = wl1271_tx_get_hlid(wl, vif, skb);
642		skb_queue_head(&wl->links[hlid].tx_queue[q], skb);
643
644		/* make sure we dequeue the same packet next time */
645		wl->last_tx_hlid = (hlid + AP_MAX_LINKS - 1) % AP_MAX_LINKS;
646	} else {
647		skb_queue_head(&wl->tx_queue[q], skb);
648	}
649
650	spin_lock_irqsave(&wl->wl_lock, flags);
651	wl->tx_queue_count[q]++;
652	spin_unlock_irqrestore(&wl->wl_lock, flags);
653}
654
655static bool wl1271_tx_is_data_present(struct sk_buff *skb)
656{
657	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *)(skb->data);
658
659	return ieee80211_is_data_present(hdr->frame_control);
660}
661
662void wl1271_tx_work_locked(struct wl1271 *wl, struct ieee80211_vif *vif)
663{
664	struct wl12xx_vif *wlvif = wl12xx_vif_to_data(vif);
665	struct sk_buff *skb;
666	u32 buf_offset = 0;
667	bool sent_packets = false;
668	bool had_data = false;
669	bool is_ap = (wlvif->bss_type == BSS_TYPE_AP_BSS);
670	int ret;
671
672	if (unlikely(wl->state == WL1271_STATE_OFF))
673		return;
674
675	while ((skb = wl1271_skb_dequeue(wl, wlvif))) {
676		if (wl1271_tx_is_data_present(skb))
677			had_data = true;
678
679		ret = wl1271_prepare_tx_frame(wl, skb, buf_offset);
680		if (ret == -EAGAIN) {
681			/*
682			 * Aggregation buffer is full.
683			 * Flush buffer and try again.
684			 */
685			wl1271_skb_queue_head(wl, vif, skb);
686			wl1271_write(wl, WL1271_SLV_MEM_DATA, wl->aggr_buf,
687				     buf_offset, true);
688			sent_packets = true;
689			buf_offset = 0;
690			continue;
691		} else if (ret == -EBUSY) {
692			/*
693			 * Firmware buffer is full.
694			 * Queue back last skb, and stop aggregating.
695			 */
696			wl1271_skb_queue_head(wl, vif, skb);
697			/* No work left, avoid scheduling redundant tx work */
698			set_bit(WL1271_FLAG_FW_TX_BUSY, &wl->flags);
699			goto out_ack;
700		} else if (ret < 0) {
701			dev_kfree_skb(skb);
702			goto out_ack;
703		}
704		buf_offset += ret;
705		wl->tx_packets_count++;
706	}
707
708out_ack:
709	if (buf_offset) {
710		wl1271_write(wl, WL1271_SLV_MEM_DATA, wl->aggr_buf,
711				buf_offset, true);
712		sent_packets = true;
713	}
714	if (sent_packets) {
715		/*
716		 * Interrupt the firmware with the new packets. This is only
717		 * required for older hardware revisions
718		 */
719		if (wl->quirks & WL12XX_QUIRK_END_OF_TRANSACTION)
720			wl1271_write32(wl, WL1271_HOST_WR_ACCESS,
721				       wl->tx_packets_count);
722
723		wl1271_handle_tx_low_watermark(wl);
724	}
725	if (!is_ap && wl->conf.rx_streaming.interval && had_data &&
726	    (wl->conf.rx_streaming.always ||
727	     test_bit(WL1271_FLAG_SOFT_GEMINI, &wl->flags))) {
728		u32 timeout = wl->conf.rx_streaming.duration;
729
730		/* enable rx streaming */
731		if (!test_bit(WL1271_FLAG_RX_STREAMING_STARTED, &wl->flags))
732			ieee80211_queue_work(wl->hw,
733					     &wl->rx_streaming_enable_work);
734
735		mod_timer(&wl->rx_streaming_timer,
736			  jiffies + msecs_to_jiffies(timeout));
737	}
738}
739
740void wl1271_tx_work(struct work_struct *work)
741{
742	struct wl1271 *wl = container_of(work, struct wl1271, tx_work);
743	int ret;
744
745	mutex_lock(&wl->mutex);
746	ret = wl1271_ps_elp_wakeup(wl);
747	if (ret < 0)
748		goto out;
749
750	wl1271_tx_work_locked(wl, wl->vif);
751
752	wl1271_ps_elp_sleep(wl);
753out:
754	mutex_unlock(&wl->mutex);
755}
756
757static void wl1271_tx_complete_packet(struct wl1271 *wl,
758				      struct wl1271_tx_hw_res_descr *result)
759{
760	struct ieee80211_tx_info *info;
761	struct sk_buff *skb;
762	int id = result->id;
763	int rate = -1;
764	u8 retries = 0;
765
766	/* check for id legality */
767	if (unlikely(id >= ACX_TX_DESCRIPTORS || wl->tx_frames[id] == NULL)) {
768		wl1271_warning("TX result illegal id: %d", id);
769		return;
770	}
771
772	skb = wl->tx_frames[id];
773	info = IEEE80211_SKB_CB(skb);
774
775	if (wl12xx_is_dummy_packet(wl, skb)) {
776		wl1271_free_tx_id(wl, id);
777		return;
778	}
779
780	/* update the TX status info */
781	if (result->status == TX_SUCCESS) {
782		if (!(info->flags & IEEE80211_TX_CTL_NO_ACK))
783			info->flags |= IEEE80211_TX_STAT_ACK;
784		rate = wl1271_rate_to_idx(result->rate_class_index, wl->band);
785		retries = result->ack_failures;
786	} else if (result->status == TX_RETRY_EXCEEDED) {
787		wl->stats.excessive_retries++;
788		retries = result->ack_failures;
789	}
790
791	info->status.rates[0].idx = rate;
792	info->status.rates[0].count = retries;
793	info->status.rates[0].flags = 0;
794	info->status.ack_signal = -1;
795
796	wl->stats.retry_count += result->ack_failures;
797
798	/*
799	 * update sequence number only when relevant, i.e. only in
800	 * sessions of TKIP, AES and GEM (not in open or WEP sessions)
801	 */
802	if (info->control.hw_key &&
803	    (info->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP ||
804	     info->control.hw_key->cipher == WLAN_CIPHER_SUITE_CCMP ||
805	     info->control.hw_key->cipher == WL1271_CIPHER_SUITE_GEM)) {
806		u8 fw_lsb = result->tx_security_sequence_number_lsb;
807		u8 cur_lsb = wl->tx_security_last_seq_lsb;
808
809		/*
810		 * update security sequence number, taking care of potential
811		 * wrap-around
812		 */
813		wl->tx_security_seq += (fw_lsb - cur_lsb + 256) % 256;
814		wl->tx_security_last_seq_lsb = fw_lsb;
815	}
816
817	/* remove private header from packet */
818	skb_pull(skb, sizeof(struct wl1271_tx_hw_descr));
819
820	/* remove TKIP header space if present */
821	if (info->control.hw_key &&
822	    info->control.hw_key->cipher == WLAN_CIPHER_SUITE_TKIP) {
823		int hdrlen = ieee80211_get_hdrlen_from_skb(skb);
824		memmove(skb->data + WL1271_TKIP_IV_SPACE, skb->data, hdrlen);
825		skb_pull(skb, WL1271_TKIP_IV_SPACE);
826	}
827
828	wl1271_debug(DEBUG_TX, "tx status id %u skb 0x%p failures %u rate 0x%x"
829		     " status 0x%x",
830		     result->id, skb, result->ack_failures,
831		     result->rate_class_index, result->status);
832
833	/* return the packet to the stack */
834	skb_queue_tail(&wl->deferred_tx_queue, skb);
835	queue_work(wl->freezable_wq, &wl->netstack_work);
836	wl1271_free_tx_id(wl, result->id);
837}
838
839/* Called upon reception of a TX complete interrupt */
840void wl1271_tx_complete(struct wl1271 *wl)
841{
842	struct wl1271_acx_mem_map *memmap =
843		(struct wl1271_acx_mem_map *)wl->target_mem_map;
844	u32 count, fw_counter;
845	u32 i;
846
847	/* read the tx results from the chipset */
848	wl1271_read(wl, le32_to_cpu(memmap->tx_result),
849		    wl->tx_res_if, sizeof(*wl->tx_res_if), false);
850	fw_counter = le32_to_cpu(wl->tx_res_if->tx_result_fw_counter);
851
852	/* write host counter to chipset (to ack) */
853	wl1271_write32(wl, le32_to_cpu(memmap->tx_result) +
854		       offsetof(struct wl1271_tx_hw_res_if,
855				tx_result_host_counter), fw_counter);
856
857	count = fw_counter - wl->tx_results_count;
858	wl1271_debug(DEBUG_TX, "tx_complete received, packets: %d", count);
859
860	/* verify that the result buffer is not getting overrun */
861	if (unlikely(count > TX_HW_RESULT_QUEUE_LEN))
862		wl1271_warning("TX result overflow from chipset: %d", count);
863
864	/* process the results */
865	for (i = 0; i < count; i++) {
866		struct wl1271_tx_hw_res_descr *result;
867		u8 offset = wl->tx_results_count & TX_HW_RESULT_QUEUE_LEN_MASK;
868
869		/* process the packet */
870		result =  &(wl->tx_res_if->tx_results_queue[offset]);
871		wl1271_tx_complete_packet(wl, result);
872
873		wl->tx_results_count++;
874	}
875}
876
877void wl1271_tx_reset_link_queues(struct wl1271 *wl, u8 hlid)
878{
879	struct sk_buff *skb;
880	int i;
881	unsigned long flags;
882	struct ieee80211_tx_info *info;
883	int total[NUM_TX_QUEUES];
884
885	for (i = 0; i < NUM_TX_QUEUES; i++) {
886		total[i] = 0;
887		while ((skb = skb_dequeue(&wl->links[hlid].tx_queue[i]))) {
888			wl1271_debug(DEBUG_TX, "link freeing skb 0x%p", skb);
889
890			if (!wl12xx_is_dummy_packet(wl, skb)) {
891				info = IEEE80211_SKB_CB(skb);
892				info->status.rates[0].idx = -1;
893				info->status.rates[0].count = 0;
894				ieee80211_tx_status_ni(wl->hw, skb);
895			}
896
897			total[i]++;
898		}
899	}
900
901	spin_lock_irqsave(&wl->wl_lock, flags);
902	for (i = 0; i < NUM_TX_QUEUES; i++)
903		wl->tx_queue_count[i] -= total[i];
904	spin_unlock_irqrestore(&wl->wl_lock, flags);
905
906	wl1271_handle_tx_low_watermark(wl);
907}
908
909/* caller must hold wl->mutex and TX must be stopped */
910void wl1271_tx_reset(struct wl1271 *wl, bool reset_tx_queues)
911{
912	struct ieee80211_vif *vif = wl->vif; /* TODO: get as param */
913	struct wl12xx_vif *wlvif = wl12xx_vif_to_data(vif);
914	int i;
915	struct sk_buff *skb;
916	struct ieee80211_tx_info *info;
917
918	/* TX failure */
919	if (wlvif->bss_type == BSS_TYPE_AP_BSS) {
920		for (i = 0; i < AP_MAX_LINKS; i++) {
921			wl1271_free_sta(wl, i);
922			wl1271_tx_reset_link_queues(wl, i);
923			wl->links[i].allocated_pkts = 0;
924			wl->links[i].prev_freed_pkts = 0;
925		}
926
927		wl->last_tx_hlid = 0;
928	} else {
929		for (i = 0; i < NUM_TX_QUEUES; i++) {
930			while ((skb = skb_dequeue(&wl->tx_queue[i]))) {
931				wl1271_debug(DEBUG_TX, "freeing skb 0x%p",
932					     skb);
933
934				if (!wl12xx_is_dummy_packet(wl, skb)) {
935					info = IEEE80211_SKB_CB(skb);
936					info->status.rates[0].idx = -1;
937					info->status.rates[0].count = 0;
938					ieee80211_tx_status_ni(wl->hw, skb);
939				}
940			}
941		}
942
943		wl->ba_rx_bitmap = 0;
944	}
945
946	for (i = 0; i < NUM_TX_QUEUES; i++)
947		wl->tx_queue_count[i] = 0;
948
949	wl->stopped_queues_map = 0;
950
951	/*
952	 * Make sure the driver is at a consistent state, in case this
953	 * function is called from a context other than interface removal.
954	 * This call will always wake the TX queues.
955	 */
956	if (reset_tx_queues)
957		wl1271_handle_tx_low_watermark(wl);
958
959	for (i = 0; i < ACX_TX_DESCRIPTORS; i++) {
960		if (wl->tx_frames[i] == NULL)
961			continue;
962
963		skb = wl->tx_frames[i];
964		wl1271_free_tx_id(wl, i);
965		wl1271_debug(DEBUG_TX, "freeing skb 0x%p", skb);
966
967		if (!wl12xx_is_dummy_packet(wl, skb)) {
968			/*
969			 * Remove private headers before passing the skb to
970			 * mac80211
971			 */
972			info = IEEE80211_SKB_CB(skb);
973			skb_pull(skb, sizeof(struct wl1271_tx_hw_descr));
974			if (info->control.hw_key &&
975			    info->control.hw_key->cipher ==
976			    WLAN_CIPHER_SUITE_TKIP) {
977				int hdrlen = ieee80211_get_hdrlen_from_skb(skb);
978				memmove(skb->data + WL1271_TKIP_IV_SPACE,
979					skb->data, hdrlen);
980				skb_pull(skb, WL1271_TKIP_IV_SPACE);
981			}
982
983			info->status.rates[0].idx = -1;
984			info->status.rates[0].count = 0;
985
986			ieee80211_tx_status_ni(wl->hw, skb);
987		}
988	}
989}
990
991#define WL1271_TX_FLUSH_TIMEOUT 500000
992
993/* caller must *NOT* hold wl->mutex */
994void wl1271_tx_flush(struct wl1271 *wl)
995{
996	unsigned long timeout;
997	timeout = jiffies + usecs_to_jiffies(WL1271_TX_FLUSH_TIMEOUT);
998
999	while (!time_after(jiffies, timeout)) {
1000		mutex_lock(&wl->mutex);
1001		wl1271_debug(DEBUG_TX, "flushing tx buffer: %d %d",
1002			     wl->tx_frames_cnt,
1003			     wl1271_tx_total_queue_count(wl));
1004		if ((wl->tx_frames_cnt == 0) &&
1005		    (wl1271_tx_total_queue_count(wl) == 0)) {
1006			mutex_unlock(&wl->mutex);
1007			return;
1008		}
1009		mutex_unlock(&wl->mutex);
1010		msleep(1);
1011	}
1012
1013	wl1271_warning("Unable to flush all TX buffers, timed out.");
1014}
1015
1016u32 wl1271_tx_min_rate_get(struct wl1271 *wl, u32 rate_set)
1017{
1018	if (WARN_ON(!rate_set))
1019		return 0;
1020
1021	return BIT(__ffs(rate_set));
1022}
1023