1 /**
2  * Copyright (c) 2014 Redpine Signals Inc.
3  *
4  * Permission to use, copy, modify, and/or distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include "rsi_mgmt.h"
18 #include "rsi_common.h"
19 #include "rsi_hal.h"
20 #include "rsi_coex.h"
21 
22 /**
23  * rsi_determine_min_weight_queue() - This function determines the queue with
24  *				      the min weight.
25  * @common: Pointer to the driver private structure.
26  *
27  * Return: q_num: Corresponding queue number.
28  */
29 static u8 rsi_determine_min_weight_queue(struct rsi_common *common)
30 {
31 	struct wmm_qinfo *tx_qinfo = common->tx_qinfo;
32 	u32 q_len = 0;
33 	u8 ii = 0;
34 
35 	for (ii = 0; ii < NUM_EDCA_QUEUES; ii++) {
36 		q_len = skb_queue_len(&common->tx_queue[ii]);
37 		if ((tx_qinfo[ii].pkt_contended) && q_len) {
38 			common->min_weight = tx_qinfo[ii].weight;
39 			break;
40 		}
41 	}
42 	return ii;
43 }
44 
45 /**
46  * rsi_recalculate_weights() - This function recalculates the weights
47  *			       corresponding to each queue.
48  * @common: Pointer to the driver private structure.
49  *
50  * Return: recontend_queue bool variable
51  */
52 static bool rsi_recalculate_weights(struct rsi_common *common)
53 {
54 	struct wmm_qinfo *tx_qinfo = common->tx_qinfo;
55 	bool recontend_queue = false;
56 	u8 ii = 0;
57 	u32 q_len = 0;
58 
59 	for (ii = 0; ii < NUM_EDCA_QUEUES; ii++) {
60 		q_len = skb_queue_len(&common->tx_queue[ii]);
61 		/* Check for the need of contention */
62 		if (q_len) {
63 			if (tx_qinfo[ii].pkt_contended) {
64 				tx_qinfo[ii].weight =
65 				((tx_qinfo[ii].weight > common->min_weight) ?
66 				 tx_qinfo[ii].weight - common->min_weight : 0);
67 			} else {
68 				tx_qinfo[ii].pkt_contended = 1;
69 				tx_qinfo[ii].weight = tx_qinfo[ii].wme_params;
70 				recontend_queue = true;
71 			}
72 		} else { /* No packets so no contention */
73 			tx_qinfo[ii].weight = 0;
74 			tx_qinfo[ii].pkt_contended = 0;
75 		}
76 	}
77 
78 	return recontend_queue;
79 }
80 
81 /**
82  * rsi_get_num_pkts_dequeue() - This function determines the number of
83  *		                packets to be dequeued based on the number
84  *			        of bytes calculated using txop.
85  *
86  * @common: Pointer to the driver private structure.
87  * @q_num: the queue from which pkts have to be dequeued
88  *
89  * Return: pkt_num: Number of pkts to be dequeued.
90  */
91 static u32 rsi_get_num_pkts_dequeue(struct rsi_common *common, u8 q_num)
92 {
93 	struct rsi_hw *adapter = common->priv;
94 	struct sk_buff *skb;
95 	u32 pkt_cnt = 0;
96 	s16 txop = common->tx_qinfo[q_num].txop * 32;
97 	__le16 r_txop;
98 	struct ieee80211_rate rate;
99 	struct ieee80211_hdr *wh;
100 	struct ieee80211_vif *vif;
101 
102 	rate.bitrate = RSI_RATE_MCS0 * 5 * 10; /* Convert to Kbps */
103 	if (q_num == VI_Q)
104 		txop = ((txop << 5) / 80);
105 
106 	if (skb_queue_len(&common->tx_queue[q_num]))
107 		skb = skb_peek(&common->tx_queue[q_num]);
108 	else
109 		return 0;
110 
111 	do {
112 		wh = (struct ieee80211_hdr *)skb->data;
113 		vif = rsi_get_vif(adapter, wh->addr2);
114 		r_txop = ieee80211_generic_frame_duration(adapter->hw,
115 							  vif,
116 							  common->band,
117 							  skb->len, &rate);
118 		txop -= le16_to_cpu(r_txop);
119 		pkt_cnt += 1;
120 		/*checking if pkts are still there*/
121 		if (skb_queue_len(&common->tx_queue[q_num]) - pkt_cnt)
122 			skb = skb->next;
123 		else
124 			break;
125 
126 	} while (txop > 0);
127 
128 	return pkt_cnt;
129 }
130 
131 /**
132  * rsi_core_determine_hal_queue() - This function determines the queue from
133  *				    which packet has to be dequeued.
134  * @common: Pointer to the driver private structure.
135  *
136  * Return: q_num: Corresponding queue number on success.
137  */
138 static u8 rsi_core_determine_hal_queue(struct rsi_common *common)
139 {
140 	bool recontend_queue = false;
141 	u32 q_len = 0;
142 	u8 q_num = INVALID_QUEUE;
143 	u8 ii = 0;
144 
145 	if (skb_queue_len(&common->tx_queue[MGMT_BEACON_Q])) {
146 		q_num = MGMT_BEACON_Q;
147 		return q_num;
148 	}
149 	if (skb_queue_len(&common->tx_queue[MGMT_SOFT_Q])) {
150 		if (!common->mgmt_q_block)
151 			q_num = MGMT_SOFT_Q;
152 		return q_num;
153 	}
154 
155 	if (common->hw_data_qs_blocked)
156 		return q_num;
157 
158 	if (common->pkt_cnt != 0) {
159 		--common->pkt_cnt;
160 		return common->selected_qnum;
161 	}
162 
163 get_queue_num:
164 	recontend_queue = false;
165 
166 	q_num = rsi_determine_min_weight_queue(common);
167 
168 	ii = q_num;
169 
170 	/* Selecting the queue with least back off */
171 	for (; ii < NUM_EDCA_QUEUES; ii++) {
172 		q_len = skb_queue_len(&common->tx_queue[ii]);
173 		if (((common->tx_qinfo[ii].pkt_contended) &&
174 		     (common->tx_qinfo[ii].weight < common->min_weight)) &&
175 		      q_len) {
176 			common->min_weight = common->tx_qinfo[ii].weight;
177 			q_num = ii;
178 		}
179 	}
180 
181 	if (q_num < NUM_EDCA_QUEUES)
182 		common->tx_qinfo[q_num].pkt_contended = 0;
183 
184 	/* Adjust the back off values for all queues again */
185 	recontend_queue = rsi_recalculate_weights(common);
186 
187 	q_len = skb_queue_len(&common->tx_queue[q_num]);
188 	if (!q_len) {
189 		/* If any queues are freshly contended and the selected queue
190 		 * doesn't have any packets
191 		 * then get the queue number again with fresh values
192 		 */
193 		if (recontend_queue)
194 			goto get_queue_num;
195 
196 		q_num = INVALID_QUEUE;
197 		return q_num;
198 	}
199 
200 	common->selected_qnum = q_num;
201 	q_len = skb_queue_len(&common->tx_queue[q_num]);
202 
203 	if (q_num == VO_Q || q_num == VI_Q) {
204 		common->pkt_cnt = rsi_get_num_pkts_dequeue(common, q_num);
205 		common->pkt_cnt -= 1;
206 	}
207 
208 	return q_num;
209 }
210 
211 /**
212  * rsi_core_queue_pkt() - This functions enqueues the packet to the queue
213  *			  specified by the queue number.
214  * @common: Pointer to the driver private structure.
215  * @skb: Pointer to the socket buffer structure.
216  *
217  * Return: None.
218  */
219 static void rsi_core_queue_pkt(struct rsi_common *common,
220 			       struct sk_buff *skb)
221 {
222 	u8 q_num = skb->priority;
223 	if (q_num >= NUM_SOFT_QUEUES) {
224 		rsi_dbg(ERR_ZONE, "%s: Invalid Queue Number: q_num = %d\n",
225 			__func__, q_num);
226 		dev_kfree_skb(skb);
227 		return;
228 	}
229 
230 	skb_queue_tail(&common->tx_queue[q_num], skb);
231 }
232 
233 /**
234  * rsi_core_dequeue_pkt() - This functions dequeues the packet from the queue
235  *			    specified by the queue number.
236  * @common: Pointer to the driver private structure.
237  * @q_num: Queue number.
238  *
239  * Return: Pointer to sk_buff structure.
240  */
241 static struct sk_buff *rsi_core_dequeue_pkt(struct rsi_common *common,
242 					    u8 q_num)
243 {
244 	if (q_num >= NUM_SOFT_QUEUES) {
245 		rsi_dbg(ERR_ZONE, "%s: Invalid Queue Number: q_num = %d\n",
246 			__func__, q_num);
247 		return NULL;
248 	}
249 
250 	return skb_dequeue(&common->tx_queue[q_num]);
251 }
252 
253 /**
254  * rsi_core_qos_processor() - This function is used to determine the wmm queue
255  *			      based on the backoff procedure. Data packets are
256  *			      dequeued from the selected hal queue and sent to
257  *			      the below layers.
258  * @common: Pointer to the driver private structure.
259  *
260  * Return: None.
261  */
262 void rsi_core_qos_processor(struct rsi_common *common)
263 {
264 	struct rsi_hw *adapter = common->priv;
265 	struct sk_buff *skb;
266 	unsigned long tstamp_1, tstamp_2;
267 	u8 q_num;
268 	int status;
269 
270 	tstamp_1 = jiffies;
271 	while (1) {
272 		q_num = rsi_core_determine_hal_queue(common);
273 		rsi_dbg(DATA_TX_ZONE,
274 			"%s: Queue number = %d\n", __func__, q_num);
275 
276 		if (q_num == INVALID_QUEUE) {
277 			rsi_dbg(DATA_TX_ZONE, "%s: No More Pkt\n", __func__);
278 			break;
279 		}
280 		if (common->hibernate_resume)
281 			break;
282 
283 		mutex_lock(&common->tx_lock);
284 
285 		status = adapter->check_hw_queue_status(adapter, q_num);
286 		if ((status <= 0)) {
287 			mutex_unlock(&common->tx_lock);
288 			break;
289 		}
290 
291 		if ((q_num < MGMT_SOFT_Q) &&
292 		    ((skb_queue_len(&common->tx_queue[q_num])) <=
293 		      MIN_DATA_QUEUE_WATER_MARK)) {
294 			if (ieee80211_queue_stopped(adapter->hw, WME_AC(q_num)))
295 				ieee80211_wake_queue(adapter->hw,
296 						     WME_AC(q_num));
297 		}
298 
299 		skb = rsi_core_dequeue_pkt(common, q_num);
300 		if (skb == NULL) {
301 			rsi_dbg(ERR_ZONE, "skb null\n");
302 			mutex_unlock(&common->tx_lock);
303 			break;
304 		}
305 		if (q_num == MGMT_BEACON_Q) {
306 			status = rsi_send_pkt_to_bus(common, skb);
307 			dev_kfree_skb(skb);
308 		} else {
309 #ifdef CONFIG_RSI_COEX
310 			if (common->coex_mode > 1) {
311 				status = rsi_coex_send_pkt(common, skb,
312 							   RSI_WLAN_Q);
313 			} else {
314 #endif
315 				if (q_num == MGMT_SOFT_Q)
316 					status = rsi_send_mgmt_pkt(common, skb);
317 				else
318 					status = rsi_send_data_pkt(common, skb);
319 #ifdef CONFIG_RSI_COEX
320 			}
321 #endif
322 		}
323 
324 		if (status) {
325 			mutex_unlock(&common->tx_lock);
326 			break;
327 		}
328 
329 		common->tx_stats.total_tx_pkt_send[q_num]++;
330 
331 		tstamp_2 = jiffies;
332 		mutex_unlock(&common->tx_lock);
333 
334 		if (time_after(tstamp_2, tstamp_1 + (300 * HZ) / 1000))
335 			schedule();
336 	}
337 }
338 
339 struct rsi_sta *rsi_find_sta(struct rsi_common *common, u8 *mac_addr)
340 {
341 	int i;
342 
343 	for (i = 0; i < common->max_stations; i++) {
344 		if (!common->stations[i].sta)
345 			continue;
346 		if (!(memcmp(common->stations[i].sta->addr,
347 			     mac_addr, ETH_ALEN)))
348 			return &common->stations[i];
349 	}
350 	return NULL;
351 }
352 
353 struct ieee80211_vif *rsi_get_vif(struct rsi_hw *adapter, u8 *mac)
354 {
355 	struct ieee80211_vif *vif;
356 	int i;
357 
358 	for (i = 0; i < RSI_MAX_VIFS; i++) {
359 		vif = adapter->vifs[i];
360 		if (!vif)
361 			continue;
362 		if (!memcmp(vif->addr, mac, ETH_ALEN))
363 			return vif;
364 	}
365 	return NULL;
366 }
367 
368 /**
369  * rsi_core_xmit() - This function transmits the packets received from mac80211
370  * @common: Pointer to the driver private structure.
371  * @skb: Pointer to the socket buffer structure.
372  *
373  * Return: None.
374  */
375 void rsi_core_xmit(struct rsi_common *common, struct sk_buff *skb)
376 {
377 	struct rsi_hw *adapter = common->priv;
378 	struct ieee80211_tx_info *info;
379 	struct skb_info *tx_params;
380 	struct ieee80211_hdr *wh = NULL;
381 	struct ieee80211_vif *vif;
382 	u8 q_num, tid = 0;
383 	struct rsi_sta *rsta = NULL;
384 
385 	if ((!skb) || (!skb->len)) {
386 		rsi_dbg(ERR_ZONE, "%s: Null skb/zero Length packet\n",
387 			__func__);
388 		goto xmit_fail;
389 	}
390 	if (common->fsm_state != FSM_MAC_INIT_DONE) {
391 		rsi_dbg(ERR_ZONE, "%s: FSM state not open\n", __func__);
392 		goto xmit_fail;
393 	}
394 	if (common->wow_flags & RSI_WOW_ENABLED) {
395 		rsi_dbg(ERR_ZONE,
396 			"%s: Blocking Tx_packets when WOWLAN is enabled\n",
397 			__func__);
398 		goto xmit_fail;
399 	}
400 
401 	info = IEEE80211_SKB_CB(skb);
402 	tx_params = (struct skb_info *)info->driver_data;
403 	wh = (struct ieee80211_hdr *)&skb->data[0];
404 	tx_params->sta_id = 0;
405 
406 	vif = rsi_get_vif(adapter, wh->addr2);
407 	if (!vif)
408 		goto xmit_fail;
409 	tx_params->vif = vif;
410 	tx_params->vap_id = ((struct vif_priv *)vif->drv_priv)->vap_id;
411 	if ((ieee80211_is_mgmt(wh->frame_control)) ||
412 	    (ieee80211_is_ctl(wh->frame_control)) ||
413 	    (ieee80211_is_qos_nullfunc(wh->frame_control))) {
414 		if (ieee80211_is_assoc_req(wh->frame_control) ||
415 		    ieee80211_is_reassoc_req(wh->frame_control)) {
416 			struct ieee80211_bss_conf *bss = &vif->bss_conf;
417 
418 			common->eapol4_confirm = false;
419 			rsi_hal_send_sta_notify_frame(common,
420 						      RSI_IFTYPE_STATION,
421 						      STA_CONNECTED, bss->bssid,
422 						      bss->qos, bss->aid, 0,
423 						      vif);
424 		}
425 
426 		q_num = MGMT_SOFT_Q;
427 		skb->priority = q_num;
428 
429 		if (rsi_prepare_mgmt_desc(common, skb)) {
430 			rsi_dbg(ERR_ZONE, "Failed to prepare desc\n");
431 			goto xmit_fail;
432 		}
433 	} else {
434 		if (ieee80211_is_data_qos(wh->frame_control)) {
435 			u8 *qos = ieee80211_get_qos_ctl(wh);
436 
437 			tid = *qos & IEEE80211_QOS_CTL_TID_MASK;
438 			skb->priority = TID_TO_WME_AC(tid);
439 		} else {
440 			tid = IEEE80211_NONQOS_TID;
441 			skb->priority = BE_Q;
442 		}
443 
444 		q_num = skb->priority;
445 		tx_params->tid = tid;
446 
447 		if (((vif->type == NL80211_IFTYPE_AP) ||
448 		     (vif->type == NL80211_IFTYPE_P2P_GO)) &&
449 		    (!is_broadcast_ether_addr(wh->addr1)) &&
450 		    (!is_multicast_ether_addr(wh->addr1))) {
451 			rsta = rsi_find_sta(common, wh->addr1);
452 			if (!rsta)
453 				goto xmit_fail;
454 			tx_params->sta_id = rsta->sta_id;
455 		} else {
456 			tx_params->sta_id = 0;
457 		}
458 
459 		if (rsta) {
460 			/* Start aggregation if not done for this tid */
461 			if (!rsta->start_tx_aggr[tid]) {
462 				rsta->start_tx_aggr[tid] = true;
463 				ieee80211_start_tx_ba_session(rsta->sta,
464 							      tid, 0);
465 			}
466 		}
467 		if (skb->protocol == cpu_to_be16(ETH_P_PAE)) {
468 			q_num = MGMT_SOFT_Q;
469 			skb->priority = q_num;
470 		}
471 		if (rsi_prepare_data_desc(common, skb)) {
472 			rsi_dbg(ERR_ZONE, "Failed to prepare data desc\n");
473 			goto xmit_fail;
474 		}
475 	}
476 
477 	if ((q_num < MGMT_SOFT_Q) &&
478 	    ((skb_queue_len(&common->tx_queue[q_num]) + 1) >=
479 	     DATA_QUEUE_WATER_MARK)) {
480 		rsi_dbg(ERR_ZONE, "%s: sw queue full\n", __func__);
481 		if (!ieee80211_queue_stopped(adapter->hw, WME_AC(q_num)))
482 			ieee80211_stop_queue(adapter->hw, WME_AC(q_num));
483 		rsi_set_event(&common->tx_thread.event);
484 		goto xmit_fail;
485 	}
486 
487 	rsi_core_queue_pkt(common, skb);
488 	rsi_dbg(DATA_TX_ZONE, "%s: ===> Scheduling TX thread <===\n", __func__);
489 	rsi_set_event(&common->tx_thread.event);
490 
491 	return;
492 
493 xmit_fail:
494 	rsi_dbg(ERR_ZONE, "%s: Failed to queue packet\n", __func__);
495 	/* Dropping pkt here */
496 	ieee80211_free_txskb(common->priv->hw, skb);
497 }
498