1 /*
2  * Copyright (c) 2013 Eugene Krasnikov <k.eugene.e@gmail.com>
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 ANY
11  * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
13  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
14  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 /* DXE - DMA transfer engine
18  * we have 2 channels(High prio and Low prio) for TX and 2 channels for RX.
19  * through low channels data packets are transfered
20  * through high channels managment packets are transfered
21  */
22 
23 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
24 
25 #include <linux/interrupt.h>
26 #include "wcn36xx.h"
27 #include "txrx.h"
28 
29 void *wcn36xx_dxe_get_next_bd(struct wcn36xx *wcn, bool is_low)
30 {
31 	struct wcn36xx_dxe_ch *ch = is_low ?
32 		&wcn->dxe_tx_l_ch :
33 		&wcn->dxe_tx_h_ch;
34 
35 	return ch->head_blk_ctl->bd_cpu_addr;
36 }
37 
38 static void wcn36xx_dxe_write_register(struct wcn36xx *wcn, int addr, int data)
39 {
40 	wcn36xx_dbg(WCN36XX_DBG_DXE,
41 		    "wcn36xx_dxe_write_register: addr=%x, data=%x\n",
42 		    addr, data);
43 
44 	writel(data, wcn->mmio + addr);
45 }
46 
47 #define wcn36xx_dxe_write_register_x(wcn, reg, reg_data)		 \
48 do {									 \
49 	if (wcn->chip_version == WCN36XX_CHIP_3680)			 \
50 		wcn36xx_dxe_write_register(wcn, reg ## _3680, reg_data); \
51 	else								 \
52 		wcn36xx_dxe_write_register(wcn, reg ## _3660, reg_data); \
53 } while (0)								 \
54 
55 static void wcn36xx_dxe_read_register(struct wcn36xx *wcn, int addr, int *data)
56 {
57 	*data = readl(wcn->mmio + addr);
58 
59 	wcn36xx_dbg(WCN36XX_DBG_DXE,
60 		    "wcn36xx_dxe_read_register: addr=%x, data=%x\n",
61 		    addr, *data);
62 }
63 
64 static void wcn36xx_dxe_free_ctl_block(struct wcn36xx_dxe_ch *ch)
65 {
66 	struct wcn36xx_dxe_ctl *ctl = ch->head_blk_ctl, *next;
67 	int i;
68 
69 	for (i = 0; i < ch->desc_num && ctl; i++) {
70 		next = ctl->next;
71 		kfree(ctl);
72 		ctl = next;
73 	}
74 }
75 
76 static int wcn36xx_dxe_allocate_ctl_block(struct wcn36xx_dxe_ch *ch)
77 {
78 	struct wcn36xx_dxe_ctl *prev_ctl = NULL;
79 	struct wcn36xx_dxe_ctl *cur_ctl = NULL;
80 	int i;
81 
82 	spin_lock_init(&ch->lock);
83 	for (i = 0; i < ch->desc_num; i++) {
84 		cur_ctl = kzalloc(sizeof(*cur_ctl), GFP_KERNEL);
85 		if (!cur_ctl)
86 			goto out_fail;
87 
88 		spin_lock_init(&cur_ctl->skb_lock);
89 		cur_ctl->ctl_blk_order = i;
90 		if (i == 0) {
91 			ch->head_blk_ctl = cur_ctl;
92 			ch->tail_blk_ctl = cur_ctl;
93 		} else if (ch->desc_num - 1 == i) {
94 			prev_ctl->next = cur_ctl;
95 			cur_ctl->next = ch->head_blk_ctl;
96 		} else {
97 			prev_ctl->next = cur_ctl;
98 		}
99 		prev_ctl = cur_ctl;
100 	}
101 
102 	return 0;
103 
104 out_fail:
105 	wcn36xx_dxe_free_ctl_block(ch);
106 	return -ENOMEM;
107 }
108 
109 int wcn36xx_dxe_alloc_ctl_blks(struct wcn36xx *wcn)
110 {
111 	int ret;
112 
113 	wcn->dxe_tx_l_ch.ch_type = WCN36XX_DXE_CH_TX_L;
114 	wcn->dxe_tx_h_ch.ch_type = WCN36XX_DXE_CH_TX_H;
115 	wcn->dxe_rx_l_ch.ch_type = WCN36XX_DXE_CH_RX_L;
116 	wcn->dxe_rx_h_ch.ch_type = WCN36XX_DXE_CH_RX_H;
117 
118 	wcn->dxe_tx_l_ch.desc_num = WCN36XX_DXE_CH_DESC_NUMB_TX_L;
119 	wcn->dxe_tx_h_ch.desc_num = WCN36XX_DXE_CH_DESC_NUMB_TX_H;
120 	wcn->dxe_rx_l_ch.desc_num = WCN36XX_DXE_CH_DESC_NUMB_RX_L;
121 	wcn->dxe_rx_h_ch.desc_num = WCN36XX_DXE_CH_DESC_NUMB_RX_H;
122 
123 	wcn->dxe_tx_l_ch.dxe_wq =  WCN36XX_DXE_WQ_TX_L;
124 	wcn->dxe_tx_h_ch.dxe_wq =  WCN36XX_DXE_WQ_TX_H;
125 
126 	wcn->dxe_tx_l_ch.ctrl_bd = WCN36XX_DXE_CTRL_TX_L_BD;
127 	wcn->dxe_tx_h_ch.ctrl_bd = WCN36XX_DXE_CTRL_TX_H_BD;
128 
129 	wcn->dxe_tx_l_ch.ctrl_skb = WCN36XX_DXE_CTRL_TX_L_SKB;
130 	wcn->dxe_tx_h_ch.ctrl_skb = WCN36XX_DXE_CTRL_TX_H_SKB;
131 
132 	wcn->dxe_tx_l_ch.reg_ctrl = WCN36XX_DXE_REG_CTL_TX_L;
133 	wcn->dxe_tx_h_ch.reg_ctrl = WCN36XX_DXE_REG_CTL_TX_H;
134 
135 	wcn->dxe_tx_l_ch.def_ctrl = WCN36XX_DXE_CH_DEFAULT_CTL_TX_L;
136 	wcn->dxe_tx_h_ch.def_ctrl = WCN36XX_DXE_CH_DEFAULT_CTL_TX_H;
137 
138 	/* DXE control block allocation */
139 	ret = wcn36xx_dxe_allocate_ctl_block(&wcn->dxe_tx_l_ch);
140 	if (ret)
141 		goto out_err;
142 	ret = wcn36xx_dxe_allocate_ctl_block(&wcn->dxe_tx_h_ch);
143 	if (ret)
144 		goto out_err;
145 	ret = wcn36xx_dxe_allocate_ctl_block(&wcn->dxe_rx_l_ch);
146 	if (ret)
147 		goto out_err;
148 	ret = wcn36xx_dxe_allocate_ctl_block(&wcn->dxe_rx_h_ch);
149 	if (ret)
150 		goto out_err;
151 
152 	/* Initialize SMSM state  Clear TX Enable RING EMPTY STATE */
153 	ret = wcn->ctrl_ops->smsm_change_state(
154 		WCN36XX_SMSM_WLAN_TX_ENABLE,
155 		WCN36XX_SMSM_WLAN_TX_RINGS_EMPTY);
156 
157 	return 0;
158 
159 out_err:
160 	wcn36xx_err("Failed to allocate DXE control blocks\n");
161 	wcn36xx_dxe_free_ctl_blks(wcn);
162 	return -ENOMEM;
163 }
164 
165 void wcn36xx_dxe_free_ctl_blks(struct wcn36xx *wcn)
166 {
167 	wcn36xx_dxe_free_ctl_block(&wcn->dxe_tx_l_ch);
168 	wcn36xx_dxe_free_ctl_block(&wcn->dxe_tx_h_ch);
169 	wcn36xx_dxe_free_ctl_block(&wcn->dxe_rx_l_ch);
170 	wcn36xx_dxe_free_ctl_block(&wcn->dxe_rx_h_ch);
171 }
172 
173 static int wcn36xx_dxe_init_descs(struct device *dev, struct wcn36xx_dxe_ch *wcn_ch)
174 {
175 	struct wcn36xx_dxe_desc *cur_dxe = NULL;
176 	struct wcn36xx_dxe_desc *prev_dxe = NULL;
177 	struct wcn36xx_dxe_ctl *cur_ctl = NULL;
178 	size_t size;
179 	int i;
180 
181 	size = wcn_ch->desc_num * sizeof(struct wcn36xx_dxe_desc);
182 	wcn_ch->cpu_addr = dma_alloc_coherent(dev, size, &wcn_ch->dma_addr,
183 					      GFP_KERNEL);
184 	if (!wcn_ch->cpu_addr)
185 		return -ENOMEM;
186 
187 	memset(wcn_ch->cpu_addr, 0, size);
188 
189 	cur_dxe = (struct wcn36xx_dxe_desc *)wcn_ch->cpu_addr;
190 	cur_ctl = wcn_ch->head_blk_ctl;
191 
192 	for (i = 0; i < wcn_ch->desc_num; i++) {
193 		cur_ctl->desc = cur_dxe;
194 		cur_ctl->desc_phy_addr = wcn_ch->dma_addr +
195 			i * sizeof(struct wcn36xx_dxe_desc);
196 
197 		switch (wcn_ch->ch_type) {
198 		case WCN36XX_DXE_CH_TX_L:
199 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_TX_L;
200 			cur_dxe->dst_addr_l = WCN36XX_DXE_WQ_TX_L;
201 			break;
202 		case WCN36XX_DXE_CH_TX_H:
203 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_TX_H;
204 			cur_dxe->dst_addr_l = WCN36XX_DXE_WQ_TX_H;
205 			break;
206 		case WCN36XX_DXE_CH_RX_L:
207 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_RX_L;
208 			cur_dxe->src_addr_l = WCN36XX_DXE_WQ_RX_L;
209 			break;
210 		case WCN36XX_DXE_CH_RX_H:
211 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_RX_H;
212 			cur_dxe->src_addr_l = WCN36XX_DXE_WQ_RX_H;
213 			break;
214 		}
215 		if (0 == i) {
216 			cur_dxe->phy_next_l = 0;
217 		} else if ((0 < i) && (i < wcn_ch->desc_num - 1)) {
218 			prev_dxe->phy_next_l =
219 				cur_ctl->desc_phy_addr;
220 		} else if (i == (wcn_ch->desc_num - 1)) {
221 			prev_dxe->phy_next_l =
222 				cur_ctl->desc_phy_addr;
223 			cur_dxe->phy_next_l =
224 				wcn_ch->head_blk_ctl->desc_phy_addr;
225 		}
226 		cur_ctl = cur_ctl->next;
227 		prev_dxe = cur_dxe;
228 		cur_dxe++;
229 	}
230 
231 	return 0;
232 }
233 
234 static void wcn36xx_dxe_init_tx_bd(struct wcn36xx_dxe_ch *ch,
235 				   struct wcn36xx_dxe_mem_pool *pool)
236 {
237 	int i, chunk_size = pool->chunk_size;
238 	dma_addr_t bd_phy_addr = pool->phy_addr;
239 	void *bd_cpu_addr = pool->virt_addr;
240 	struct wcn36xx_dxe_ctl *cur = ch->head_blk_ctl;
241 
242 	for (i = 0; i < ch->desc_num; i++) {
243 		/* Only every second dxe needs a bd pointer,
244 		   the other will point to the skb data */
245 		if (!(i & 1)) {
246 			cur->bd_phy_addr = bd_phy_addr;
247 			cur->bd_cpu_addr = bd_cpu_addr;
248 			bd_phy_addr += chunk_size;
249 			bd_cpu_addr += chunk_size;
250 		} else {
251 			cur->bd_phy_addr = 0;
252 			cur->bd_cpu_addr = NULL;
253 		}
254 		cur = cur->next;
255 	}
256 }
257 
258 static int wcn36xx_dxe_enable_ch_int(struct wcn36xx *wcn, u16 wcn_ch)
259 {
260 	int reg_data = 0;
261 
262 	wcn36xx_dxe_read_register(wcn,
263 				  WCN36XX_DXE_INT_MASK_REG,
264 				  &reg_data);
265 
266 	reg_data |= wcn_ch;
267 
268 	wcn36xx_dxe_write_register(wcn,
269 				   WCN36XX_DXE_INT_MASK_REG,
270 				   (int)reg_data);
271 	return 0;
272 }
273 
274 static int wcn36xx_dxe_fill_skb(struct device *dev, struct wcn36xx_dxe_ctl *ctl)
275 {
276 	struct wcn36xx_dxe_desc *dxe = ctl->desc;
277 	struct sk_buff *skb;
278 
279 	skb = alloc_skb(WCN36XX_PKT_SIZE, GFP_ATOMIC);
280 	if (skb == NULL)
281 		return -ENOMEM;
282 
283 	dxe->dst_addr_l = dma_map_single(dev,
284 					 skb_tail_pointer(skb),
285 					 WCN36XX_PKT_SIZE,
286 					 DMA_FROM_DEVICE);
287 	ctl->skb = skb;
288 
289 	return 0;
290 }
291 
292 static int wcn36xx_dxe_ch_alloc_skb(struct wcn36xx *wcn,
293 				    struct wcn36xx_dxe_ch *wcn_ch)
294 {
295 	int i;
296 	struct wcn36xx_dxe_ctl *cur_ctl = NULL;
297 
298 	cur_ctl = wcn_ch->head_blk_ctl;
299 
300 	for (i = 0; i < wcn_ch->desc_num; i++) {
301 		wcn36xx_dxe_fill_skb(wcn->dev, cur_ctl);
302 		cur_ctl = cur_ctl->next;
303 	}
304 
305 	return 0;
306 }
307 
308 static void wcn36xx_dxe_ch_free_skbs(struct wcn36xx *wcn,
309 				     struct wcn36xx_dxe_ch *wcn_ch)
310 {
311 	struct wcn36xx_dxe_ctl *cur = wcn_ch->head_blk_ctl;
312 	int i;
313 
314 	for (i = 0; i < wcn_ch->desc_num; i++) {
315 		kfree_skb(cur->skb);
316 		cur = cur->next;
317 	}
318 }
319 
320 void wcn36xx_dxe_tx_ack_ind(struct wcn36xx *wcn, u32 status)
321 {
322 	struct ieee80211_tx_info *info;
323 	struct sk_buff *skb;
324 	unsigned long flags;
325 
326 	spin_lock_irqsave(&wcn->dxe_lock, flags);
327 	skb = wcn->tx_ack_skb;
328 	wcn->tx_ack_skb = NULL;
329 	spin_unlock_irqrestore(&wcn->dxe_lock, flags);
330 
331 	if (!skb) {
332 		wcn36xx_warn("Spurious TX complete indication\n");
333 		return;
334 	}
335 
336 	info = IEEE80211_SKB_CB(skb);
337 
338 	if (status == 1)
339 		info->flags |= IEEE80211_TX_STAT_ACK;
340 
341 	wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ack status: %d\n", status);
342 
343 	ieee80211_tx_status_irqsafe(wcn->hw, skb);
344 	ieee80211_wake_queues(wcn->hw);
345 }
346 
347 static void reap_tx_dxes(struct wcn36xx *wcn, struct wcn36xx_dxe_ch *ch)
348 {
349 	struct wcn36xx_dxe_ctl *ctl;
350 	struct ieee80211_tx_info *info;
351 	unsigned long flags;
352 
353 	/*
354 	 * Make at least one loop of do-while because in case ring is
355 	 * completely full head and tail are pointing to the same element
356 	 * and while-do will not make any cycles.
357 	 */
358 	spin_lock_irqsave(&ch->lock, flags);
359 	ctl = ch->tail_blk_ctl;
360 	do {
361 		if (ctl->desc->ctrl & WCN36XX_DXE_CTRL_VALID_MASK)
362 			break;
363 		if (ctl->skb) {
364 			dma_unmap_single(wcn->dev, ctl->desc->src_addr_l,
365 					 ctl->skb->len, DMA_TO_DEVICE);
366 			info = IEEE80211_SKB_CB(ctl->skb);
367 			if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS)) {
368 				/* Keep frame until TX status comes */
369 				ieee80211_free_txskb(wcn->hw, ctl->skb);
370 			}
371 			spin_lock(&ctl->skb_lock);
372 			if (wcn->queues_stopped) {
373 				wcn->queues_stopped = false;
374 				ieee80211_wake_queues(wcn->hw);
375 			}
376 			spin_unlock(&ctl->skb_lock);
377 
378 			ctl->skb = NULL;
379 		}
380 		ctl = ctl->next;
381 	} while (ctl != ch->head_blk_ctl &&
382 	       !(ctl->desc->ctrl & WCN36XX_DXE_CTRL_VALID_MASK));
383 
384 	ch->tail_blk_ctl = ctl;
385 	spin_unlock_irqrestore(&ch->lock, flags);
386 }
387 
388 static irqreturn_t wcn36xx_irq_tx_complete(int irq, void *dev)
389 {
390 	struct wcn36xx *wcn = (struct wcn36xx *)dev;
391 	int int_src, int_reason;
392 
393 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_INT_SRC_RAW_REG, &int_src);
394 
395 	if (int_src & WCN36XX_INT_MASK_CHAN_TX_H) {
396 		wcn36xx_dxe_read_register(wcn,
397 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_TX_H,
398 					  &int_reason);
399 
400 		/* TODO: Check int_reason */
401 
402 		wcn36xx_dxe_write_register(wcn,
403 					   WCN36XX_DXE_0_INT_CLR,
404 					   WCN36XX_INT_MASK_CHAN_TX_H);
405 
406 		wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_0_INT_ED_CLR,
407 					   WCN36XX_INT_MASK_CHAN_TX_H);
408 		wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ready high\n");
409 		reap_tx_dxes(wcn, &wcn->dxe_tx_h_ch);
410 	}
411 
412 	if (int_src & WCN36XX_INT_MASK_CHAN_TX_L) {
413 		wcn36xx_dxe_read_register(wcn,
414 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_TX_L,
415 					  &int_reason);
416 		/* TODO: Check int_reason */
417 
418 		wcn36xx_dxe_write_register(wcn,
419 					   WCN36XX_DXE_0_INT_CLR,
420 					   WCN36XX_INT_MASK_CHAN_TX_L);
421 
422 		wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_0_INT_ED_CLR,
423 					   WCN36XX_INT_MASK_CHAN_TX_L);
424 		wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ready low\n");
425 		reap_tx_dxes(wcn, &wcn->dxe_tx_l_ch);
426 	}
427 
428 	return IRQ_HANDLED;
429 }
430 
431 static irqreturn_t wcn36xx_irq_rx_ready(int irq, void *dev)
432 {
433 	struct wcn36xx *wcn = (struct wcn36xx *)dev;
434 
435 	disable_irq_nosync(wcn->rx_irq);
436 	wcn36xx_dxe_rx_frame(wcn);
437 	enable_irq(wcn->rx_irq);
438 	return IRQ_HANDLED;
439 }
440 
441 static int wcn36xx_dxe_request_irqs(struct wcn36xx *wcn)
442 {
443 	int ret;
444 
445 	ret = request_irq(wcn->tx_irq, wcn36xx_irq_tx_complete,
446 			  IRQF_TRIGGER_HIGH, "wcn36xx_tx", wcn);
447 	if (ret) {
448 		wcn36xx_err("failed to alloc tx irq\n");
449 		goto out_err;
450 	}
451 
452 	ret = request_irq(wcn->rx_irq, wcn36xx_irq_rx_ready, IRQF_TRIGGER_HIGH,
453 			  "wcn36xx_rx", wcn);
454 	if (ret) {
455 		wcn36xx_err("failed to alloc rx irq\n");
456 		goto out_txirq;
457 	}
458 
459 	enable_irq_wake(wcn->rx_irq);
460 
461 	return 0;
462 
463 out_txirq:
464 	free_irq(wcn->tx_irq, wcn);
465 out_err:
466 	return ret;
467 
468 }
469 
470 static int wcn36xx_rx_handle_packets(struct wcn36xx *wcn,
471 				     struct wcn36xx_dxe_ch *ch)
472 {
473 	struct wcn36xx_dxe_ctl *ctl = ch->head_blk_ctl;
474 	struct wcn36xx_dxe_desc *dxe = ctl->desc;
475 	dma_addr_t  dma_addr;
476 	struct sk_buff *skb;
477 
478 	while (!(dxe->ctrl & WCN36XX_DXE_CTRL_VALID_MASK)) {
479 		skb = ctl->skb;
480 		dma_addr = dxe->dst_addr_l;
481 		wcn36xx_dxe_fill_skb(wcn->dev, ctl);
482 
483 		switch (ch->ch_type) {
484 		case WCN36XX_DXE_CH_RX_L:
485 			dxe->ctrl = WCN36XX_DXE_CTRL_RX_L;
486 			wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_ENCH_ADDR,
487 						   WCN36XX_DXE_INT_CH1_MASK);
488 			break;
489 		case WCN36XX_DXE_CH_RX_H:
490 			dxe->ctrl = WCN36XX_DXE_CTRL_RX_H;
491 			wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_ENCH_ADDR,
492 						   WCN36XX_DXE_INT_CH3_MASK);
493 			break;
494 		default:
495 			wcn36xx_warn("Unknown channel\n");
496 		}
497 
498 		dma_unmap_single(wcn->dev, dma_addr, WCN36XX_PKT_SIZE,
499 				 DMA_FROM_DEVICE);
500 		wcn36xx_rx_skb(wcn, skb);
501 		ctl = ctl->next;
502 		dxe = ctl->desc;
503 	}
504 
505 	ch->head_blk_ctl = ctl;
506 
507 	return 0;
508 }
509 
510 void wcn36xx_dxe_rx_frame(struct wcn36xx *wcn)
511 {
512 	int int_src;
513 
514 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_INT_SRC_RAW_REG, &int_src);
515 
516 	/* RX_LOW_PRI */
517 	if (int_src & WCN36XX_DXE_INT_CH1_MASK) {
518 		wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_0_INT_CLR,
519 					   WCN36XX_DXE_INT_CH1_MASK);
520 		wcn36xx_rx_handle_packets(wcn, &(wcn->dxe_rx_l_ch));
521 	}
522 
523 	/* RX_HIGH_PRI */
524 	if (int_src & WCN36XX_DXE_INT_CH3_MASK) {
525 		/* Clean up all the INT within this channel */
526 		wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_0_INT_CLR,
527 					   WCN36XX_DXE_INT_CH3_MASK);
528 		wcn36xx_rx_handle_packets(wcn, &(wcn->dxe_rx_h_ch));
529 	}
530 
531 	if (!int_src)
532 		wcn36xx_warn("No DXE interrupt pending\n");
533 }
534 
535 int wcn36xx_dxe_allocate_mem_pools(struct wcn36xx *wcn)
536 {
537 	size_t s;
538 	void *cpu_addr;
539 
540 	/* Allocate BD headers for MGMT frames */
541 
542 	/* Where this come from ask QC */
543 	wcn->mgmt_mem_pool.chunk_size =	WCN36XX_BD_CHUNK_SIZE +
544 		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
545 
546 	s = wcn->mgmt_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_H;
547 	cpu_addr = dma_alloc_coherent(wcn->dev, s, &wcn->mgmt_mem_pool.phy_addr,
548 				      GFP_KERNEL);
549 	if (!cpu_addr)
550 		goto out_err;
551 
552 	wcn->mgmt_mem_pool.virt_addr = cpu_addr;
553 	memset(cpu_addr, 0, s);
554 
555 	/* Allocate BD headers for DATA frames */
556 
557 	/* Where this come from ask QC */
558 	wcn->data_mem_pool.chunk_size = WCN36XX_BD_CHUNK_SIZE +
559 		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
560 
561 	s = wcn->data_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_L;
562 	cpu_addr = dma_alloc_coherent(wcn->dev, s, &wcn->data_mem_pool.phy_addr,
563 				      GFP_KERNEL);
564 	if (!cpu_addr)
565 		goto out_err;
566 
567 	wcn->data_mem_pool.virt_addr = cpu_addr;
568 	memset(cpu_addr, 0, s);
569 
570 	return 0;
571 
572 out_err:
573 	wcn36xx_dxe_free_mem_pools(wcn);
574 	wcn36xx_err("Failed to allocate BD mempool\n");
575 	return -ENOMEM;
576 }
577 
578 void wcn36xx_dxe_free_mem_pools(struct wcn36xx *wcn)
579 {
580 	if (wcn->mgmt_mem_pool.virt_addr)
581 		dma_free_coherent(wcn->dev, wcn->mgmt_mem_pool.chunk_size *
582 				  WCN36XX_DXE_CH_DESC_NUMB_TX_H,
583 				  wcn->mgmt_mem_pool.virt_addr,
584 				  wcn->mgmt_mem_pool.phy_addr);
585 
586 	if (wcn->data_mem_pool.virt_addr) {
587 		dma_free_coherent(wcn->dev, wcn->data_mem_pool.chunk_size *
588 				  WCN36XX_DXE_CH_DESC_NUMB_TX_L,
589 				  wcn->data_mem_pool.virt_addr,
590 				  wcn->data_mem_pool.phy_addr);
591 	}
592 }
593 
594 int wcn36xx_dxe_tx_frame(struct wcn36xx *wcn,
595 			 struct wcn36xx_vif *vif_priv,
596 			 struct sk_buff *skb,
597 			 bool is_low)
598 {
599 	struct wcn36xx_dxe_ctl *ctl = NULL;
600 	struct wcn36xx_dxe_desc *desc = NULL;
601 	struct wcn36xx_dxe_ch *ch = NULL;
602 	unsigned long flags;
603 	int ret;
604 
605 	ch = is_low ? &wcn->dxe_tx_l_ch : &wcn->dxe_tx_h_ch;
606 
607 	spin_lock_irqsave(&ch->lock, flags);
608 	ctl = ch->head_blk_ctl;
609 
610 	spin_lock(&ctl->next->skb_lock);
611 
612 	/*
613 	 * If skb is not null that means that we reached the tail of the ring
614 	 * hence ring is full. Stop queues to let mac80211 back off until ring
615 	 * has an empty slot again.
616 	 */
617 	if (NULL != ctl->next->skb) {
618 		ieee80211_stop_queues(wcn->hw);
619 		wcn->queues_stopped = true;
620 		spin_unlock(&ctl->next->skb_lock);
621 		spin_unlock_irqrestore(&ch->lock, flags);
622 		return -EBUSY;
623 	}
624 	spin_unlock(&ctl->next->skb_lock);
625 
626 	ctl->skb = NULL;
627 	desc = ctl->desc;
628 
629 	/* Set source address of the BD we send */
630 	desc->src_addr_l = ctl->bd_phy_addr;
631 
632 	desc->dst_addr_l = ch->dxe_wq;
633 	desc->fr_len = sizeof(struct wcn36xx_tx_bd);
634 	desc->ctrl = ch->ctrl_bd;
635 
636 	wcn36xx_dbg(WCN36XX_DBG_DXE, "DXE TX\n");
637 
638 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "DESC1 >>> ",
639 			 (char *)desc, sizeof(*desc));
640 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP,
641 			 "BD   >>> ", (char *)ctl->bd_cpu_addr,
642 			 sizeof(struct wcn36xx_tx_bd));
643 
644 	/* Set source address of the SKB we send */
645 	ctl = ctl->next;
646 	ctl->skb = skb;
647 	desc = ctl->desc;
648 	if (ctl->bd_cpu_addr) {
649 		wcn36xx_err("bd_cpu_addr cannot be NULL for skb DXE\n");
650 		ret = -EINVAL;
651 		goto unlock;
652 	}
653 
654 	desc->src_addr_l = dma_map_single(wcn->dev,
655 					  ctl->skb->data,
656 					  ctl->skb->len,
657 					  DMA_TO_DEVICE);
658 
659 	desc->dst_addr_l = ch->dxe_wq;
660 	desc->fr_len = ctl->skb->len;
661 
662 	/* set dxe descriptor to VALID */
663 	desc->ctrl = ch->ctrl_skb;
664 
665 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "DESC2 >>> ",
666 			 (char *)desc, sizeof(*desc));
667 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "SKB   >>> ",
668 			 (char *)ctl->skb->data, ctl->skb->len);
669 
670 	/* Move the head of the ring to the next empty descriptor */
671 	 ch->head_blk_ctl = ctl->next;
672 
673 	/*
674 	 * When connected and trying to send data frame chip can be in sleep
675 	 * mode and writing to the register will not wake up the chip. Instead
676 	 * notify chip about new frame through SMSM bus.
677 	 */
678 	if (is_low &&  vif_priv->pw_state == WCN36XX_BMPS) {
679 		wcn->ctrl_ops->smsm_change_state(
680 				  0,
681 				  WCN36XX_SMSM_WLAN_TX_ENABLE);
682 	} else {
683 		/* indicate End Of Packet and generate interrupt on descriptor
684 		 * done.
685 		 */
686 		wcn36xx_dxe_write_register(wcn,
687 			ch->reg_ctrl, ch->def_ctrl);
688 	}
689 
690 	ret = 0;
691 unlock:
692 	spin_unlock_irqrestore(&ch->lock, flags);
693 	return ret;
694 }
695 
696 int wcn36xx_dxe_init(struct wcn36xx *wcn)
697 {
698 	int reg_data = 0, ret;
699 
700 	reg_data = WCN36XX_DXE_REG_RESET;
701 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_REG_CSR_RESET, reg_data);
702 
703 	/* Setting interrupt path */
704 	reg_data = WCN36XX_DXE_CCU_INT;
705 	wcn36xx_dxe_write_register_x(wcn, WCN36XX_DXE_REG_CCU_INT, reg_data);
706 
707 	/***************************************/
708 	/* Init descriptors for TX LOW channel */
709 	/***************************************/
710 	wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_tx_l_ch);
711 	wcn36xx_dxe_init_tx_bd(&wcn->dxe_tx_l_ch, &wcn->data_mem_pool);
712 
713 	/* Write channel head to a NEXT register */
714 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_TX_L,
715 		wcn->dxe_tx_l_ch.head_blk_ctl->desc_phy_addr);
716 
717 	/* Program DMA destination addr for TX LOW */
718 	wcn36xx_dxe_write_register(wcn,
719 		WCN36XX_DXE_CH_DEST_ADDR_TX_L,
720 		WCN36XX_DXE_WQ_TX_L);
721 
722 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_REG_CH_EN, &reg_data);
723 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_TX_L);
724 
725 	/***************************************/
726 	/* Init descriptors for TX HIGH channel */
727 	/***************************************/
728 	wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_tx_h_ch);
729 	wcn36xx_dxe_init_tx_bd(&wcn->dxe_tx_h_ch, &wcn->mgmt_mem_pool);
730 
731 	/* Write channel head to a NEXT register */
732 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_TX_H,
733 		wcn->dxe_tx_h_ch.head_blk_ctl->desc_phy_addr);
734 
735 	/* Program DMA destination addr for TX HIGH */
736 	wcn36xx_dxe_write_register(wcn,
737 		WCN36XX_DXE_CH_DEST_ADDR_TX_H,
738 		WCN36XX_DXE_WQ_TX_H);
739 
740 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_REG_CH_EN, &reg_data);
741 
742 	/* Enable channel interrupts */
743 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_TX_H);
744 
745 	/***************************************/
746 	/* Init descriptors for RX LOW channel */
747 	/***************************************/
748 	wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_rx_l_ch);
749 
750 	/* For RX we need to preallocated buffers */
751 	wcn36xx_dxe_ch_alloc_skb(wcn, &wcn->dxe_rx_l_ch);
752 
753 	/* Write channel head to a NEXT register */
754 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_RX_L,
755 		wcn->dxe_rx_l_ch.head_blk_ctl->desc_phy_addr);
756 
757 	/* Write DMA source address */
758 	wcn36xx_dxe_write_register(wcn,
759 		WCN36XX_DXE_CH_SRC_ADDR_RX_L,
760 		WCN36XX_DXE_WQ_RX_L);
761 
762 	/* Program preallocated destination address */
763 	wcn36xx_dxe_write_register(wcn,
764 		WCN36XX_DXE_CH_DEST_ADDR_RX_L,
765 		wcn->dxe_rx_l_ch.head_blk_ctl->desc->phy_next_l);
766 
767 	/* Enable default control registers */
768 	wcn36xx_dxe_write_register(wcn,
769 		WCN36XX_DXE_REG_CTL_RX_L,
770 		WCN36XX_DXE_CH_DEFAULT_CTL_RX_L);
771 
772 	/* Enable channel interrupts */
773 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_L);
774 
775 	/***************************************/
776 	/* Init descriptors for RX HIGH channel */
777 	/***************************************/
778 	wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_rx_h_ch);
779 
780 	/* For RX we need to prealocat buffers */
781 	wcn36xx_dxe_ch_alloc_skb(wcn, &wcn->dxe_rx_h_ch);
782 
783 	/* Write chanel head to a NEXT register */
784 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_RX_H,
785 		wcn->dxe_rx_h_ch.head_blk_ctl->desc_phy_addr);
786 
787 	/* Write DMA source address */
788 	wcn36xx_dxe_write_register(wcn,
789 		WCN36XX_DXE_CH_SRC_ADDR_RX_H,
790 		WCN36XX_DXE_WQ_RX_H);
791 
792 	/* Program preallocated destination address */
793 	wcn36xx_dxe_write_register(wcn,
794 		WCN36XX_DXE_CH_DEST_ADDR_RX_H,
795 		 wcn->dxe_rx_h_ch.head_blk_ctl->desc->phy_next_l);
796 
797 	/* Enable default control registers */
798 	wcn36xx_dxe_write_register(wcn,
799 		WCN36XX_DXE_REG_CTL_RX_H,
800 		WCN36XX_DXE_CH_DEFAULT_CTL_RX_H);
801 
802 	/* Enable channel interrupts */
803 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_H);
804 
805 	ret = wcn36xx_dxe_request_irqs(wcn);
806 	if (ret < 0)
807 		goto out_err;
808 
809 	return 0;
810 
811 out_err:
812 	return ret;
813 }
814 
815 void wcn36xx_dxe_deinit(struct wcn36xx *wcn)
816 {
817 	free_irq(wcn->tx_irq, wcn);
818 	free_irq(wcn->rx_irq, wcn);
819 
820 	if (wcn->tx_ack_skb) {
821 		ieee80211_tx_status_irqsafe(wcn->hw, wcn->tx_ack_skb);
822 		wcn->tx_ack_skb = NULL;
823 	}
824 
825 	wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_l_ch);
826 	wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_h_ch);
827 }
828