1 /*
2  * Copyright (C) 2016 Felix Fietkau <nbd@nbd.name>
3  * Copyright (C) 2018 Lorenzo Bianconi <lorenzo.bianconi83@gmail.com>
4  *
5  * Permission to use, copy, modify, and/or distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <linux/kernel.h>
19 #include <linux/irq.h>
20 
21 #include "mt76x02.h"
22 #include "mt76x02_trace.h"
23 
24 struct beacon_bc_data {
25 	struct mt76x02_dev *dev;
26 	struct sk_buff_head q;
27 	struct sk_buff *tail[8];
28 };
29 
30 static void
31 mt76x02_update_beacon_iter(void *priv, u8 *mac, struct ieee80211_vif *vif)
32 {
33 	struct mt76x02_dev *dev = (struct mt76x02_dev *)priv;
34 	struct mt76x02_vif *mvif = (struct mt76x02_vif *)vif->drv_priv;
35 	struct sk_buff *skb = NULL;
36 
37 	if (!(dev->beacon_mask & BIT(mvif->idx)))
38 		return;
39 
40 	skb = ieee80211_beacon_get(mt76_hw(dev), vif);
41 	if (!skb)
42 		return;
43 
44 	mt76x02_mac_set_beacon(dev, mvif->idx, skb);
45 }
46 
47 static void
48 mt76x02_add_buffered_bc(void *priv, u8 *mac, struct ieee80211_vif *vif)
49 {
50 	struct beacon_bc_data *data = priv;
51 	struct mt76x02_dev *dev = data->dev;
52 	struct mt76x02_vif *mvif = (struct mt76x02_vif *)vif->drv_priv;
53 	struct ieee80211_tx_info *info;
54 	struct sk_buff *skb;
55 
56 	if (!(dev->beacon_mask & BIT(mvif->idx)))
57 		return;
58 
59 	skb = ieee80211_get_buffered_bc(mt76_hw(dev), vif);
60 	if (!skb)
61 		return;
62 
63 	info = IEEE80211_SKB_CB(skb);
64 	info->control.vif = vif;
65 	info->flags |= IEEE80211_TX_CTL_ASSIGN_SEQ;
66 	mt76_skb_set_moredata(skb, true);
67 	__skb_queue_tail(&data->q, skb);
68 	data->tail[mvif->idx] = skb;
69 }
70 
71 static void
72 mt76x02_resync_beacon_timer(struct mt76x02_dev *dev)
73 {
74 	u32 timer_val = dev->beacon_int << 4;
75 
76 	dev->tbtt_count++;
77 
78 	/*
79 	 * Beacon timer drifts by 1us every tick, the timer is configured
80 	 * in 1/16 TU (64us) units.
81 	 */
82 	if (dev->tbtt_count < 63)
83 		return;
84 
85 	/*
86 	 * The updated beacon interval takes effect after two TBTT, because
87 	 * at this point the original interval has already been loaded into
88 	 * the next TBTT_TIMER value
89 	 */
90 	if (dev->tbtt_count == 63)
91 		timer_val -= 1;
92 
93 	mt76_rmw_field(dev, MT_BEACON_TIME_CFG,
94 		       MT_BEACON_TIME_CFG_INTVAL, timer_val);
95 
96 	if (dev->tbtt_count >= 64) {
97 		dev->tbtt_count = 0;
98 		return;
99 	}
100 }
101 
102 static void mt76x02_pre_tbtt_tasklet(unsigned long arg)
103 {
104 	struct mt76x02_dev *dev = (struct mt76x02_dev *)arg;
105 	struct mt76_queue *q = &dev->mt76.q_tx[MT_TXQ_PSD];
106 	struct beacon_bc_data data = {};
107 	struct sk_buff *skb;
108 	int i, nframes;
109 
110 	mt76x02_resync_beacon_timer(dev);
111 
112 	data.dev = dev;
113 	__skb_queue_head_init(&data.q);
114 
115 	ieee80211_iterate_active_interfaces_atomic(mt76_hw(dev),
116 		IEEE80211_IFACE_ITER_RESUME_ALL,
117 		mt76x02_update_beacon_iter, dev);
118 
119 	mt76_csa_check(&dev->mt76);
120 
121 	if (dev->mt76.csa_complete)
122 		return;
123 
124 	do {
125 		nframes = skb_queue_len(&data.q);
126 		ieee80211_iterate_active_interfaces_atomic(mt76_hw(dev),
127 			IEEE80211_IFACE_ITER_RESUME_ALL,
128 			mt76x02_add_buffered_bc, &data);
129 	} while (nframes != skb_queue_len(&data.q) &&
130 		 skb_queue_len(&data.q) < 8);
131 
132 	if (!skb_queue_len(&data.q))
133 		return;
134 
135 	for (i = 0; i < ARRAY_SIZE(data.tail); i++) {
136 		if (!data.tail[i])
137 			continue;
138 
139 		mt76_skb_set_moredata(data.tail[i], false);
140 	}
141 
142 	spin_lock_bh(&q->lock);
143 	while ((skb = __skb_dequeue(&data.q)) != NULL) {
144 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
145 		struct ieee80211_vif *vif = info->control.vif;
146 		struct mt76x02_vif *mvif = (struct mt76x02_vif *)vif->drv_priv;
147 
148 		mt76_dma_tx_queue_skb(&dev->mt76, q, skb, &mvif->group_wcid,
149 				      NULL);
150 	}
151 	spin_unlock_bh(&q->lock);
152 }
153 
154 static int
155 mt76x02_init_tx_queue(struct mt76x02_dev *dev, struct mt76_queue *q,
156 		      int idx, int n_desc)
157 {
158 	int ret;
159 
160 	q->regs = dev->mt76.mmio.regs + MT_TX_RING_BASE + idx * MT_RING_SIZE;
161 	q->ndesc = n_desc;
162 	q->hw_idx = idx;
163 
164 	ret = mt76_queue_alloc(dev, q);
165 	if (ret)
166 		return ret;
167 
168 	mt76x02_irq_enable(dev, MT_INT_TX_DONE(idx));
169 
170 	return 0;
171 }
172 
173 static int
174 mt76x02_init_rx_queue(struct mt76x02_dev *dev, struct mt76_queue *q,
175 		      int idx, int n_desc, int bufsize)
176 {
177 	int ret;
178 
179 	q->regs = dev->mt76.mmio.regs + MT_RX_RING_BASE + idx * MT_RING_SIZE;
180 	q->ndesc = n_desc;
181 	q->buf_size = bufsize;
182 
183 	ret = mt76_queue_alloc(dev, q);
184 	if (ret)
185 		return ret;
186 
187 	mt76x02_irq_enable(dev, MT_INT_RX_DONE(idx));
188 
189 	return 0;
190 }
191 
192 static void mt76x02_process_tx_status_fifo(struct mt76x02_dev *dev)
193 {
194 	struct mt76x02_tx_status stat;
195 	u8 update = 1;
196 
197 	while (kfifo_get(&dev->txstatus_fifo, &stat))
198 		mt76x02_send_tx_status(dev, &stat, &update);
199 }
200 
201 static void mt76x02_tx_tasklet(unsigned long data)
202 {
203 	struct mt76x02_dev *dev = (struct mt76x02_dev *)data;
204 	int i;
205 
206 	mt76x02_process_tx_status_fifo(dev);
207 
208 	for (i = MT_TXQ_MCU; i >= 0; i--)
209 		mt76_queue_tx_cleanup(dev, i, false);
210 
211 	mt76x02_mac_poll_tx_status(dev, false);
212 	mt76x02_irq_enable(dev, MT_INT_TX_DONE_ALL);
213 }
214 
215 int mt76x02_dma_init(struct mt76x02_dev *dev)
216 {
217 	struct mt76_txwi_cache __maybe_unused *t;
218 	int i, ret, fifo_size;
219 	struct mt76_queue *q;
220 	void *status_fifo;
221 
222 	BUILD_BUG_ON(sizeof(t->txwi) < sizeof(struct mt76x02_txwi));
223 	BUILD_BUG_ON(sizeof(struct mt76x02_rxwi) > MT_RX_HEADROOM);
224 
225 	fifo_size = roundup_pow_of_two(32 * sizeof(struct mt76x02_tx_status));
226 	status_fifo = devm_kzalloc(dev->mt76.dev, fifo_size, GFP_KERNEL);
227 	if (!status_fifo)
228 		return -ENOMEM;
229 
230 	tasklet_init(&dev->tx_tasklet, mt76x02_tx_tasklet, (unsigned long) dev);
231 	tasklet_init(&dev->pre_tbtt_tasklet, mt76x02_pre_tbtt_tasklet,
232 		     (unsigned long)dev);
233 
234 	kfifo_init(&dev->txstatus_fifo, status_fifo, fifo_size);
235 
236 	mt76_dma_attach(&dev->mt76);
237 
238 	mt76_wr(dev, MT_WPDMA_RST_IDX, ~0);
239 
240 	for (i = 0; i < IEEE80211_NUM_ACS; i++) {
241 		ret = mt76x02_init_tx_queue(dev, &dev->mt76.q_tx[i],
242 					    mt76_ac_to_hwq(i),
243 					    MT_TX_RING_SIZE);
244 		if (ret)
245 			return ret;
246 	}
247 
248 	ret = mt76x02_init_tx_queue(dev, &dev->mt76.q_tx[MT_TXQ_PSD],
249 				    MT_TX_HW_QUEUE_MGMT, MT_TX_RING_SIZE);
250 	if (ret)
251 		return ret;
252 
253 	ret = mt76x02_init_tx_queue(dev, &dev->mt76.q_tx[MT_TXQ_MCU],
254 				    MT_TX_HW_QUEUE_MCU, MT_MCU_RING_SIZE);
255 	if (ret)
256 		return ret;
257 
258 	ret = mt76x02_init_rx_queue(dev, &dev->mt76.q_rx[MT_RXQ_MCU], 1,
259 				    MT_MCU_RING_SIZE, MT_RX_BUF_SIZE);
260 	if (ret)
261 		return ret;
262 
263 	q = &dev->mt76.q_rx[MT_RXQ_MAIN];
264 	q->buf_offset = MT_RX_HEADROOM - sizeof(struct mt76x02_rxwi);
265 	ret = mt76x02_init_rx_queue(dev, q, 0, MT76X02_RX_RING_SIZE,
266 				    MT_RX_BUF_SIZE);
267 	if (ret)
268 		return ret;
269 
270 	return mt76_init_queues(dev);
271 }
272 EXPORT_SYMBOL_GPL(mt76x02_dma_init);
273 
274 void mt76x02_rx_poll_complete(struct mt76_dev *mdev, enum mt76_rxq_id q)
275 {
276 	struct mt76x02_dev *dev;
277 
278 	dev = container_of(mdev, struct mt76x02_dev, mt76);
279 	mt76x02_irq_enable(dev, MT_INT_RX_DONE(q));
280 }
281 EXPORT_SYMBOL_GPL(mt76x02_rx_poll_complete);
282 
283 irqreturn_t mt76x02_irq_handler(int irq, void *dev_instance)
284 {
285 	struct mt76x02_dev *dev = dev_instance;
286 	u32 intr;
287 
288 	intr = mt76_rr(dev, MT_INT_SOURCE_CSR);
289 	mt76_wr(dev, MT_INT_SOURCE_CSR, intr);
290 
291 	if (!test_bit(MT76_STATE_INITIALIZED, &dev->mt76.state))
292 		return IRQ_NONE;
293 
294 	trace_dev_irq(dev, intr, dev->mt76.mmio.irqmask);
295 
296 	intr &= dev->mt76.mmio.irqmask;
297 
298 	if (intr & MT_INT_TX_DONE_ALL) {
299 		mt76x02_irq_disable(dev, MT_INT_TX_DONE_ALL);
300 		tasklet_schedule(&dev->tx_tasklet);
301 	}
302 
303 	if (intr & MT_INT_RX_DONE(0)) {
304 		mt76x02_irq_disable(dev, MT_INT_RX_DONE(0));
305 		napi_schedule(&dev->mt76.napi[0]);
306 	}
307 
308 	if (intr & MT_INT_RX_DONE(1)) {
309 		mt76x02_irq_disable(dev, MT_INT_RX_DONE(1));
310 		napi_schedule(&dev->mt76.napi[1]);
311 	}
312 
313 	if (intr & MT_INT_PRE_TBTT)
314 		tasklet_schedule(&dev->pre_tbtt_tasklet);
315 
316 	/* send buffered multicast frames now */
317 	if (intr & MT_INT_TBTT) {
318 		if (dev->mt76.csa_complete)
319 			mt76_csa_finish(&dev->mt76);
320 		else
321 			mt76_queue_kick(dev, &dev->mt76.q_tx[MT_TXQ_PSD]);
322 	}
323 
324 	if (intr & MT_INT_TX_STAT) {
325 		mt76x02_mac_poll_tx_status(dev, true);
326 		tasklet_schedule(&dev->tx_tasklet);
327 	}
328 
329 	if (intr & MT_INT_GPTIMER) {
330 		mt76x02_irq_disable(dev, MT_INT_GPTIMER);
331 		tasklet_schedule(&dev->dfs_pd.dfs_tasklet);
332 	}
333 
334 	return IRQ_HANDLED;
335 }
336 EXPORT_SYMBOL_GPL(mt76x02_irq_handler);
337 
338 void mt76x02_set_irq_mask(struct mt76x02_dev *dev, u32 clear, u32 set)
339 {
340 	unsigned long flags;
341 
342 	spin_lock_irqsave(&dev->mt76.mmio.irq_lock, flags);
343 	dev->mt76.mmio.irqmask &= ~clear;
344 	dev->mt76.mmio.irqmask |= set;
345 	mt76_wr(dev, MT_INT_MASK_CSR, dev->mt76.mmio.irqmask);
346 	spin_unlock_irqrestore(&dev->mt76.mmio.irq_lock, flags);
347 }
348 EXPORT_SYMBOL_GPL(mt76x02_set_irq_mask);
349 
350 static void mt76x02_dma_enable(struct mt76x02_dev *dev)
351 {
352 	u32 val;
353 
354 	mt76_wr(dev, MT_MAC_SYS_CTRL, MT_MAC_SYS_CTRL_ENABLE_TX);
355 	mt76x02_wait_for_wpdma(&dev->mt76, 1000);
356 	usleep_range(50, 100);
357 
358 	val = FIELD_PREP(MT_WPDMA_GLO_CFG_DMA_BURST_SIZE, 3) |
359 	      MT_WPDMA_GLO_CFG_TX_DMA_EN |
360 	      MT_WPDMA_GLO_CFG_RX_DMA_EN;
361 	mt76_set(dev, MT_WPDMA_GLO_CFG, val);
362 	mt76_clear(dev, MT_WPDMA_GLO_CFG,
363 		   MT_WPDMA_GLO_CFG_TX_WRITEBACK_DONE);
364 }
365 
366 void mt76x02_dma_cleanup(struct mt76x02_dev *dev)
367 {
368 	tasklet_kill(&dev->tx_tasklet);
369 	mt76_dma_cleanup(&dev->mt76);
370 }
371 EXPORT_SYMBOL_GPL(mt76x02_dma_cleanup);
372 
373 void mt76x02_dma_disable(struct mt76x02_dev *dev)
374 {
375 	u32 val = mt76_rr(dev, MT_WPDMA_GLO_CFG);
376 
377 	val &= MT_WPDMA_GLO_CFG_DMA_BURST_SIZE |
378 	       MT_WPDMA_GLO_CFG_BIG_ENDIAN |
379 	       MT_WPDMA_GLO_CFG_HDR_SEG_LEN;
380 	val |= MT_WPDMA_GLO_CFG_TX_WRITEBACK_DONE;
381 	mt76_wr(dev, MT_WPDMA_GLO_CFG, val);
382 }
383 EXPORT_SYMBOL_GPL(mt76x02_dma_disable);
384 
385 void mt76x02_mac_start(struct mt76x02_dev *dev)
386 {
387 	mt76x02_dma_enable(dev);
388 	mt76_wr(dev, MT_RX_FILTR_CFG, dev->mt76.rxfilter);
389 	mt76_wr(dev, MT_MAC_SYS_CTRL,
390 		MT_MAC_SYS_CTRL_ENABLE_TX |
391 		MT_MAC_SYS_CTRL_ENABLE_RX);
392 	mt76x02_irq_enable(dev,
393 			   MT_INT_RX_DONE_ALL | MT_INT_TX_DONE_ALL |
394 			   MT_INT_TX_STAT);
395 }
396 EXPORT_SYMBOL_GPL(mt76x02_mac_start);
397 
398 static bool mt76x02_tx_hang(struct mt76x02_dev *dev)
399 {
400 	u32 dma_idx, prev_dma_idx;
401 	struct mt76_queue *q;
402 	int i;
403 
404 	for (i = 0; i < 4; i++) {
405 		q = &dev->mt76.q_tx[i];
406 
407 		if (!q->queued)
408 			continue;
409 
410 		prev_dma_idx = dev->mt76.tx_dma_idx[i];
411 		dma_idx = ioread32(&q->regs->dma_idx);
412 		dev->mt76.tx_dma_idx[i] = dma_idx;
413 
414 		if (prev_dma_idx == dma_idx)
415 			break;
416 	}
417 
418 	return i < 4;
419 }
420 
421 static void mt76x02_watchdog_reset(struct mt76x02_dev *dev)
422 {
423 	u32 mask = dev->mt76.mmio.irqmask;
424 	int i;
425 
426 	ieee80211_stop_queues(dev->mt76.hw);
427 	set_bit(MT76_RESET, &dev->mt76.state);
428 
429 	tasklet_disable(&dev->pre_tbtt_tasklet);
430 	tasklet_disable(&dev->tx_tasklet);
431 
432 	for (i = 0; i < ARRAY_SIZE(dev->mt76.napi); i++)
433 		napi_disable(&dev->mt76.napi[i]);
434 
435 	mutex_lock(&dev->mt76.mutex);
436 
437 	if (dev->beacon_mask)
438 		mt76_clear(dev, MT_BEACON_TIME_CFG,
439 			   MT_BEACON_TIME_CFG_BEACON_TX |
440 			   MT_BEACON_TIME_CFG_TBTT_EN);
441 
442 	mt76x02_irq_disable(dev, mask);
443 
444 	/* perform device reset */
445 	mt76_clear(dev, MT_TXOP_CTRL_CFG, MT_TXOP_ED_CCA_EN);
446 	mt76_wr(dev, MT_MAC_SYS_CTRL, 0);
447 	mt76_clear(dev, MT_WPDMA_GLO_CFG,
448 		   MT_WPDMA_GLO_CFG_TX_DMA_EN | MT_WPDMA_GLO_CFG_RX_DMA_EN);
449 	usleep_range(5000, 10000);
450 	mt76_wr(dev, MT_INT_SOURCE_CSR, 0xffffffff);
451 
452 	/* let fw reset DMA */
453 	mt76_set(dev, 0x734, 0x3);
454 
455 	for (i = 0; i < ARRAY_SIZE(dev->mt76.q_tx); i++)
456 		mt76_queue_tx_cleanup(dev, i, true);
457 
458 	for (i = 0; i < ARRAY_SIZE(dev->mt76.q_rx); i++)
459 		mt76_queue_rx_reset(dev, i);
460 
461 	mt76_wr(dev, MT_MAC_SYS_CTRL,
462 		MT_MAC_SYS_CTRL_ENABLE_TX | MT_MAC_SYS_CTRL_ENABLE_RX);
463 	mt76_set(dev, MT_WPDMA_GLO_CFG,
464 		 MT_WPDMA_GLO_CFG_TX_DMA_EN | MT_WPDMA_GLO_CFG_RX_DMA_EN);
465 	if (dev->ed_monitor)
466 		mt76_set(dev, MT_TXOP_CTRL_CFG, MT_TXOP_ED_CCA_EN);
467 
468 	if (dev->beacon_mask)
469 		mt76_set(dev, MT_BEACON_TIME_CFG,
470 			 MT_BEACON_TIME_CFG_BEACON_TX |
471 			 MT_BEACON_TIME_CFG_TBTT_EN);
472 
473 	mt76x02_irq_enable(dev, mask);
474 
475 	mutex_unlock(&dev->mt76.mutex);
476 
477 	clear_bit(MT76_RESET, &dev->mt76.state);
478 
479 	tasklet_enable(&dev->tx_tasklet);
480 	tasklet_schedule(&dev->tx_tasklet);
481 
482 	tasklet_enable(&dev->pre_tbtt_tasklet);
483 
484 	for (i = 0; i < ARRAY_SIZE(dev->mt76.napi); i++) {
485 		napi_enable(&dev->mt76.napi[i]);
486 		napi_schedule(&dev->mt76.napi[i]);
487 	}
488 
489 	ieee80211_wake_queues(dev->mt76.hw);
490 
491 	mt76_txq_schedule_all(&dev->mt76);
492 }
493 
494 static void mt76x02_check_tx_hang(struct mt76x02_dev *dev)
495 {
496 	if (mt76x02_tx_hang(dev)) {
497 		if (++dev->tx_hang_check >= MT_TX_HANG_TH)
498 			goto restart;
499 	} else {
500 		dev->tx_hang_check = 0;
501 	}
502 
503 	if (dev->mcu_timeout)
504 		goto restart;
505 
506 	return;
507 
508 restart:
509 	mt76x02_watchdog_reset(dev);
510 
511 	mutex_lock(&dev->mt76.mmio.mcu.mutex);
512 	dev->mcu_timeout = 0;
513 	mutex_unlock(&dev->mt76.mmio.mcu.mutex);
514 
515 	dev->tx_hang_reset++;
516 	dev->tx_hang_check = 0;
517 	memset(dev->mt76.tx_dma_idx, 0xff,
518 	       sizeof(dev->mt76.tx_dma_idx));
519 }
520 
521 void mt76x02_wdt_work(struct work_struct *work)
522 {
523 	struct mt76x02_dev *dev = container_of(work, struct mt76x02_dev,
524 					       wdt_work.work);
525 
526 	mt76x02_check_tx_hang(dev);
527 
528 	ieee80211_queue_delayed_work(mt76_hw(dev), &dev->wdt_work,
529 				     MT_WATCHDOG_TIME);
530 }
531