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 <linux/soc/qcom/smem_state.h>
27 #include "wcn36xx.h"
28 #include "txrx.h"
29 
30 static void wcn36xx_ccu_write_register(struct wcn36xx *wcn, int addr, int data)
31 {
32 	wcn36xx_dbg(WCN36XX_DBG_DXE,
33 		    "wcn36xx_ccu_write_register: addr=%x, data=%x\n",
34 		    addr, data);
35 
36 	writel(data, wcn->ccu_base + addr);
37 }
38 
39 static void wcn36xx_dxe_write_register(struct wcn36xx *wcn, int addr, int data)
40 {
41 	wcn36xx_dbg(WCN36XX_DBG_DXE,
42 		    "wcn36xx_dxe_write_register: addr=%x, data=%x\n",
43 		    addr, data);
44 
45 	writel(data, wcn->dxe_base + addr);
46 }
47 
48 static void wcn36xx_dxe_read_register(struct wcn36xx *wcn, int addr, int *data)
49 {
50 	*data = readl(wcn->dxe_base + addr);
51 
52 	wcn36xx_dbg(WCN36XX_DBG_DXE,
53 		    "wcn36xx_dxe_read_register: addr=%x, data=%x\n",
54 		    addr, *data);
55 }
56 
57 static void wcn36xx_dxe_free_ctl_block(struct wcn36xx_dxe_ch *ch)
58 {
59 	struct wcn36xx_dxe_ctl *ctl = ch->head_blk_ctl, *next;
60 	int i;
61 
62 	for (i = 0; i < ch->desc_num && ctl; i++) {
63 		next = ctl->next;
64 		kfree(ctl);
65 		ctl = next;
66 	}
67 }
68 
69 static int wcn36xx_dxe_allocate_ctl_block(struct wcn36xx_dxe_ch *ch)
70 {
71 	struct wcn36xx_dxe_ctl *prev_ctl = NULL;
72 	struct wcn36xx_dxe_ctl *cur_ctl = NULL;
73 	int i;
74 
75 	spin_lock_init(&ch->lock);
76 	for (i = 0; i < ch->desc_num; i++) {
77 		cur_ctl = kzalloc(sizeof(*cur_ctl), GFP_KERNEL);
78 		if (!cur_ctl)
79 			goto out_fail;
80 
81 		cur_ctl->ctl_blk_order = i;
82 		if (i == 0) {
83 			ch->head_blk_ctl = cur_ctl;
84 			ch->tail_blk_ctl = cur_ctl;
85 		} else if (ch->desc_num - 1 == i) {
86 			prev_ctl->next = cur_ctl;
87 			cur_ctl->next = ch->head_blk_ctl;
88 		} else {
89 			prev_ctl->next = cur_ctl;
90 		}
91 		prev_ctl = cur_ctl;
92 	}
93 
94 	return 0;
95 
96 out_fail:
97 	wcn36xx_dxe_free_ctl_block(ch);
98 	return -ENOMEM;
99 }
100 
101 int wcn36xx_dxe_alloc_ctl_blks(struct wcn36xx *wcn)
102 {
103 	int ret;
104 
105 	wcn->dxe_tx_l_ch.ch_type = WCN36XX_DXE_CH_TX_L;
106 	wcn->dxe_tx_h_ch.ch_type = WCN36XX_DXE_CH_TX_H;
107 	wcn->dxe_rx_l_ch.ch_type = WCN36XX_DXE_CH_RX_L;
108 	wcn->dxe_rx_h_ch.ch_type = WCN36XX_DXE_CH_RX_H;
109 
110 	wcn->dxe_tx_l_ch.desc_num = WCN36XX_DXE_CH_DESC_NUMB_TX_L;
111 	wcn->dxe_tx_h_ch.desc_num = WCN36XX_DXE_CH_DESC_NUMB_TX_H;
112 	wcn->dxe_rx_l_ch.desc_num = WCN36XX_DXE_CH_DESC_NUMB_RX_L;
113 	wcn->dxe_rx_h_ch.desc_num = WCN36XX_DXE_CH_DESC_NUMB_RX_H;
114 
115 	wcn->dxe_tx_l_ch.dxe_wq =  WCN36XX_DXE_WQ_TX_L;
116 	wcn->dxe_tx_h_ch.dxe_wq =  WCN36XX_DXE_WQ_TX_H;
117 
118 	wcn->dxe_tx_l_ch.ctrl_bd = WCN36XX_DXE_CTRL_TX_L_BD;
119 	wcn->dxe_tx_h_ch.ctrl_bd = WCN36XX_DXE_CTRL_TX_H_BD;
120 
121 	wcn->dxe_tx_l_ch.ctrl_skb = WCN36XX_DXE_CTRL_TX_L_SKB;
122 	wcn->dxe_tx_h_ch.ctrl_skb = WCN36XX_DXE_CTRL_TX_H_SKB;
123 
124 	wcn->dxe_tx_l_ch.reg_ctrl = WCN36XX_DXE_REG_CTL_TX_L;
125 	wcn->dxe_tx_h_ch.reg_ctrl = WCN36XX_DXE_REG_CTL_TX_H;
126 
127 	wcn->dxe_tx_l_ch.def_ctrl = WCN36XX_DXE_CH_DEFAULT_CTL_TX_L;
128 	wcn->dxe_tx_h_ch.def_ctrl = WCN36XX_DXE_CH_DEFAULT_CTL_TX_H;
129 
130 	/* DXE control block allocation */
131 	ret = wcn36xx_dxe_allocate_ctl_block(&wcn->dxe_tx_l_ch);
132 	if (ret)
133 		goto out_err;
134 	ret = wcn36xx_dxe_allocate_ctl_block(&wcn->dxe_tx_h_ch);
135 	if (ret)
136 		goto out_err;
137 	ret = wcn36xx_dxe_allocate_ctl_block(&wcn->dxe_rx_l_ch);
138 	if (ret)
139 		goto out_err;
140 	ret = wcn36xx_dxe_allocate_ctl_block(&wcn->dxe_rx_h_ch);
141 	if (ret)
142 		goto out_err;
143 
144 	/* Initialize SMSM state  Clear TX Enable RING EMPTY STATE */
145 	ret = qcom_smem_state_update_bits(wcn->tx_enable_state,
146 					  WCN36XX_SMSM_WLAN_TX_ENABLE |
147 					  WCN36XX_SMSM_WLAN_TX_RINGS_EMPTY,
148 					  WCN36XX_SMSM_WLAN_TX_RINGS_EMPTY);
149 	if (ret)
150 		goto out_err;
151 
152 	return 0;
153 
154 out_err:
155 	wcn36xx_err("Failed to allocate DXE control blocks\n");
156 	wcn36xx_dxe_free_ctl_blks(wcn);
157 	return -ENOMEM;
158 }
159 
160 void wcn36xx_dxe_free_ctl_blks(struct wcn36xx *wcn)
161 {
162 	wcn36xx_dxe_free_ctl_block(&wcn->dxe_tx_l_ch);
163 	wcn36xx_dxe_free_ctl_block(&wcn->dxe_tx_h_ch);
164 	wcn36xx_dxe_free_ctl_block(&wcn->dxe_rx_l_ch);
165 	wcn36xx_dxe_free_ctl_block(&wcn->dxe_rx_h_ch);
166 }
167 
168 static int wcn36xx_dxe_init_descs(struct device *dev, struct wcn36xx_dxe_ch *wcn_ch)
169 {
170 	struct wcn36xx_dxe_desc *cur_dxe = NULL;
171 	struct wcn36xx_dxe_desc *prev_dxe = NULL;
172 	struct wcn36xx_dxe_ctl *cur_ctl = NULL;
173 	size_t size;
174 	int i;
175 
176 	size = wcn_ch->desc_num * sizeof(struct wcn36xx_dxe_desc);
177 	wcn_ch->cpu_addr = dma_alloc_coherent(dev, size, &wcn_ch->dma_addr,
178 					      GFP_KERNEL);
179 	if (!wcn_ch->cpu_addr)
180 		return -ENOMEM;
181 
182 	memset(wcn_ch->cpu_addr, 0, size);
183 
184 	cur_dxe = (struct wcn36xx_dxe_desc *)wcn_ch->cpu_addr;
185 	cur_ctl = wcn_ch->head_blk_ctl;
186 
187 	for (i = 0; i < wcn_ch->desc_num; i++) {
188 		cur_ctl->desc = cur_dxe;
189 		cur_ctl->desc_phy_addr = wcn_ch->dma_addr +
190 			i * sizeof(struct wcn36xx_dxe_desc);
191 
192 		switch (wcn_ch->ch_type) {
193 		case WCN36XX_DXE_CH_TX_L:
194 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_TX_L;
195 			cur_dxe->dst_addr_l = WCN36XX_DXE_WQ_TX_L;
196 			break;
197 		case WCN36XX_DXE_CH_TX_H:
198 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_TX_H;
199 			cur_dxe->dst_addr_l = WCN36XX_DXE_WQ_TX_H;
200 			break;
201 		case WCN36XX_DXE_CH_RX_L:
202 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_RX_L;
203 			cur_dxe->src_addr_l = WCN36XX_DXE_WQ_RX_L;
204 			break;
205 		case WCN36XX_DXE_CH_RX_H:
206 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_RX_H;
207 			cur_dxe->src_addr_l = WCN36XX_DXE_WQ_RX_H;
208 			break;
209 		}
210 		if (0 == i) {
211 			cur_dxe->phy_next_l = 0;
212 		} else if ((0 < i) && (i < wcn_ch->desc_num - 1)) {
213 			prev_dxe->phy_next_l =
214 				cur_ctl->desc_phy_addr;
215 		} else if (i == (wcn_ch->desc_num - 1)) {
216 			prev_dxe->phy_next_l =
217 				cur_ctl->desc_phy_addr;
218 			cur_dxe->phy_next_l =
219 				wcn_ch->head_blk_ctl->desc_phy_addr;
220 		}
221 		cur_ctl = cur_ctl->next;
222 		prev_dxe = cur_dxe;
223 		cur_dxe++;
224 	}
225 
226 	return 0;
227 }
228 
229 static void wcn36xx_dxe_deinit_descs(struct device *dev, struct wcn36xx_dxe_ch *wcn_ch)
230 {
231 	size_t size;
232 
233 	size = wcn_ch->desc_num * sizeof(struct wcn36xx_dxe_desc);
234 	dma_free_coherent(dev, size,wcn_ch->cpu_addr, wcn_ch->dma_addr);
235 }
236 
237 static void wcn36xx_dxe_init_tx_bd(struct wcn36xx_dxe_ch *ch,
238 				   struct wcn36xx_dxe_mem_pool *pool)
239 {
240 	int i, chunk_size = pool->chunk_size;
241 	dma_addr_t bd_phy_addr = pool->phy_addr;
242 	void *bd_cpu_addr = pool->virt_addr;
243 	struct wcn36xx_dxe_ctl *cur = ch->head_blk_ctl;
244 
245 	for (i = 0; i < ch->desc_num; i++) {
246 		/* Only every second dxe needs a bd pointer,
247 		   the other will point to the skb data */
248 		if (!(i & 1)) {
249 			cur->bd_phy_addr = bd_phy_addr;
250 			cur->bd_cpu_addr = bd_cpu_addr;
251 			bd_phy_addr += chunk_size;
252 			bd_cpu_addr += chunk_size;
253 		} else {
254 			cur->bd_phy_addr = 0;
255 			cur->bd_cpu_addr = NULL;
256 		}
257 		cur = cur->next;
258 	}
259 }
260 
261 static int wcn36xx_dxe_enable_ch_int(struct wcn36xx *wcn, u16 wcn_ch)
262 {
263 	int reg_data = 0;
264 
265 	wcn36xx_dxe_read_register(wcn,
266 				  WCN36XX_DXE_INT_MASK_REG,
267 				  &reg_data);
268 
269 	reg_data |= wcn_ch;
270 
271 	wcn36xx_dxe_write_register(wcn,
272 				   WCN36XX_DXE_INT_MASK_REG,
273 				   (int)reg_data);
274 	return 0;
275 }
276 
277 static int wcn36xx_dxe_fill_skb(struct device *dev,
278 				struct wcn36xx_dxe_ctl *ctl,
279 				gfp_t gfp)
280 {
281 	struct wcn36xx_dxe_desc *dxe = ctl->desc;
282 	struct sk_buff *skb;
283 
284 	skb = alloc_skb(WCN36XX_PKT_SIZE, gfp);
285 	if (skb == NULL)
286 		return -ENOMEM;
287 
288 	dxe->dst_addr_l = dma_map_single(dev,
289 					 skb_tail_pointer(skb),
290 					 WCN36XX_PKT_SIZE,
291 					 DMA_FROM_DEVICE);
292 	if (dma_mapping_error(dev, dxe->dst_addr_l)) {
293 		dev_err(dev, "unable to map skb\n");
294 		kfree_skb(skb);
295 		return -ENOMEM;
296 	}
297 	ctl->skb = skb;
298 
299 	return 0;
300 }
301 
302 static int wcn36xx_dxe_ch_alloc_skb(struct wcn36xx *wcn,
303 				    struct wcn36xx_dxe_ch *wcn_ch)
304 {
305 	int i;
306 	struct wcn36xx_dxe_ctl *cur_ctl = NULL;
307 
308 	cur_ctl = wcn_ch->head_blk_ctl;
309 
310 	for (i = 0; i < wcn_ch->desc_num; i++) {
311 		wcn36xx_dxe_fill_skb(wcn->dev, cur_ctl, GFP_KERNEL);
312 		cur_ctl = cur_ctl->next;
313 	}
314 
315 	return 0;
316 }
317 
318 static void wcn36xx_dxe_ch_free_skbs(struct wcn36xx *wcn,
319 				     struct wcn36xx_dxe_ch *wcn_ch)
320 {
321 	struct wcn36xx_dxe_ctl *cur = wcn_ch->head_blk_ctl;
322 	int i;
323 
324 	for (i = 0; i < wcn_ch->desc_num; i++) {
325 		kfree_skb(cur->skb);
326 		cur = cur->next;
327 	}
328 }
329 
330 void wcn36xx_dxe_tx_ack_ind(struct wcn36xx *wcn, u32 status)
331 {
332 	struct ieee80211_tx_info *info;
333 	struct sk_buff *skb;
334 	unsigned long flags;
335 
336 	spin_lock_irqsave(&wcn->dxe_lock, flags);
337 	skb = wcn->tx_ack_skb;
338 	wcn->tx_ack_skb = NULL;
339 	spin_unlock_irqrestore(&wcn->dxe_lock, flags);
340 
341 	if (!skb) {
342 		wcn36xx_warn("Spurious TX complete indication\n");
343 		return;
344 	}
345 
346 	info = IEEE80211_SKB_CB(skb);
347 
348 	if (status == 1)
349 		info->flags |= IEEE80211_TX_STAT_ACK;
350 
351 	wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ack status: %d\n", status);
352 
353 	ieee80211_tx_status_irqsafe(wcn->hw, skb);
354 	ieee80211_wake_queues(wcn->hw);
355 }
356 
357 static void reap_tx_dxes(struct wcn36xx *wcn, struct wcn36xx_dxe_ch *ch)
358 {
359 	struct wcn36xx_dxe_ctl *ctl;
360 	struct ieee80211_tx_info *info;
361 	unsigned long flags;
362 
363 	/*
364 	 * Make at least one loop of do-while because in case ring is
365 	 * completely full head and tail are pointing to the same element
366 	 * and while-do will not make any cycles.
367 	 */
368 	spin_lock_irqsave(&ch->lock, flags);
369 	ctl = ch->tail_blk_ctl;
370 	do {
371 		if (READ_ONCE(ctl->desc->ctrl) & WCN36xx_DXE_CTRL_VLD)
372 			break;
373 		if (ctl->skb) {
374 			dma_unmap_single(wcn->dev, ctl->desc->src_addr_l,
375 					 ctl->skb->len, DMA_TO_DEVICE);
376 			info = IEEE80211_SKB_CB(ctl->skb);
377 			if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS)) {
378 				/* Keep frame until TX status comes */
379 				ieee80211_free_txskb(wcn->hw, ctl->skb);
380 			}
381 
382 			if (wcn->queues_stopped) {
383 				wcn->queues_stopped = false;
384 				ieee80211_wake_queues(wcn->hw);
385 			}
386 
387 			ctl->skb = NULL;
388 		}
389 		ctl = ctl->next;
390 	} while (ctl != ch->head_blk_ctl);
391 
392 	ch->tail_blk_ctl = ctl;
393 	spin_unlock_irqrestore(&ch->lock, flags);
394 }
395 
396 static irqreturn_t wcn36xx_irq_tx_complete(int irq, void *dev)
397 {
398 	struct wcn36xx *wcn = (struct wcn36xx *)dev;
399 	int int_src, int_reason;
400 
401 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_INT_SRC_RAW_REG, &int_src);
402 
403 	if (int_src & WCN36XX_INT_MASK_CHAN_TX_H) {
404 		wcn36xx_dxe_read_register(wcn,
405 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_TX_H,
406 					  &int_reason);
407 
408 		wcn36xx_dxe_write_register(wcn,
409 					   WCN36XX_DXE_0_INT_CLR,
410 					   WCN36XX_INT_MASK_CHAN_TX_H);
411 
412 		if (int_reason & WCN36XX_CH_STAT_INT_ERR_MASK ) {
413 			wcn36xx_dxe_write_register(wcn,
414 						   WCN36XX_DXE_0_INT_ERR_CLR,
415 						   WCN36XX_INT_MASK_CHAN_TX_H);
416 
417 			wcn36xx_err("DXE IRQ reported error: 0x%x in high TX channel\n",
418 					int_src);
419 		}
420 
421 		if (int_reason & WCN36XX_CH_STAT_INT_DONE_MASK) {
422 			wcn36xx_dxe_write_register(wcn,
423 						   WCN36XX_DXE_0_INT_DONE_CLR,
424 						   WCN36XX_INT_MASK_CHAN_TX_H);
425 		}
426 
427 		if (int_reason & WCN36XX_CH_STAT_INT_ED_MASK) {
428 			wcn36xx_dxe_write_register(wcn,
429 						   WCN36XX_DXE_0_INT_ED_CLR,
430 						   WCN36XX_INT_MASK_CHAN_TX_H);
431 		}
432 
433 		wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ready high\n");
434 		reap_tx_dxes(wcn, &wcn->dxe_tx_h_ch);
435 	}
436 
437 	if (int_src & WCN36XX_INT_MASK_CHAN_TX_L) {
438 		wcn36xx_dxe_read_register(wcn,
439 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_TX_L,
440 					  &int_reason);
441 
442 		wcn36xx_dxe_write_register(wcn,
443 					   WCN36XX_DXE_0_INT_CLR,
444 					   WCN36XX_INT_MASK_CHAN_TX_L);
445 
446 
447 		if (int_reason & WCN36XX_CH_STAT_INT_ERR_MASK ) {
448 			wcn36xx_dxe_write_register(wcn,
449 						   WCN36XX_DXE_0_INT_ERR_CLR,
450 						   WCN36XX_INT_MASK_CHAN_TX_L);
451 
452 			wcn36xx_err("DXE IRQ reported error: 0x%x in low TX channel\n",
453 					int_src);
454 		}
455 
456 		if (int_reason & WCN36XX_CH_STAT_INT_DONE_MASK) {
457 			wcn36xx_dxe_write_register(wcn,
458 						   WCN36XX_DXE_0_INT_DONE_CLR,
459 						   WCN36XX_INT_MASK_CHAN_TX_L);
460 		}
461 
462 		if (int_reason & WCN36XX_CH_STAT_INT_ED_MASK) {
463 			wcn36xx_dxe_write_register(wcn,
464 						   WCN36XX_DXE_0_INT_ED_CLR,
465 						   WCN36XX_INT_MASK_CHAN_TX_L);
466 		}
467 
468 		wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ready low\n");
469 		reap_tx_dxes(wcn, &wcn->dxe_tx_l_ch);
470 	}
471 
472 	return IRQ_HANDLED;
473 }
474 
475 static irqreturn_t wcn36xx_irq_rx_ready(int irq, void *dev)
476 {
477 	struct wcn36xx *wcn = (struct wcn36xx *)dev;
478 
479 	disable_irq_nosync(wcn->rx_irq);
480 	wcn36xx_dxe_rx_frame(wcn);
481 	enable_irq(wcn->rx_irq);
482 	return IRQ_HANDLED;
483 }
484 
485 static int wcn36xx_dxe_request_irqs(struct wcn36xx *wcn)
486 {
487 	int ret;
488 
489 	ret = request_irq(wcn->tx_irq, wcn36xx_irq_tx_complete,
490 			  IRQF_TRIGGER_HIGH, "wcn36xx_tx", wcn);
491 	if (ret) {
492 		wcn36xx_err("failed to alloc tx irq\n");
493 		goto out_err;
494 	}
495 
496 	ret = request_irq(wcn->rx_irq, wcn36xx_irq_rx_ready, IRQF_TRIGGER_HIGH,
497 			  "wcn36xx_rx", wcn);
498 	if (ret) {
499 		wcn36xx_err("failed to alloc rx irq\n");
500 		goto out_txirq;
501 	}
502 
503 	enable_irq_wake(wcn->rx_irq);
504 
505 	return 0;
506 
507 out_txirq:
508 	free_irq(wcn->tx_irq, wcn);
509 out_err:
510 	return ret;
511 
512 }
513 
514 static int wcn36xx_rx_handle_packets(struct wcn36xx *wcn,
515 				     struct wcn36xx_dxe_ch *ch)
516 {
517 	struct wcn36xx_dxe_ctl *ctl = ch->head_blk_ctl;
518 	struct wcn36xx_dxe_desc *dxe = ctl->desc;
519 	dma_addr_t  dma_addr;
520 	struct sk_buff *skb;
521 	int ret = 0, int_mask;
522 	u32 value;
523 
524 	if (ch->ch_type == WCN36XX_DXE_CH_RX_L) {
525 		value = WCN36XX_DXE_CTRL_RX_L;
526 		int_mask = WCN36XX_DXE_INT_CH1_MASK;
527 	} else {
528 		value = WCN36XX_DXE_CTRL_RX_H;
529 		int_mask = WCN36XX_DXE_INT_CH3_MASK;
530 	}
531 
532 	while (!(READ_ONCE(dxe->ctrl) & WCN36xx_DXE_CTRL_VLD)) {
533 		skb = ctl->skb;
534 		dma_addr = dxe->dst_addr_l;
535 		ret = wcn36xx_dxe_fill_skb(wcn->dev, ctl, GFP_ATOMIC);
536 		if (0 == ret) {
537 			/* new skb allocation ok. Use the new one and queue
538 			 * the old one to network system.
539 			 */
540 			dma_unmap_single(wcn->dev, dma_addr, WCN36XX_PKT_SIZE,
541 					DMA_FROM_DEVICE);
542 			wcn36xx_rx_skb(wcn, skb);
543 		} /* else keep old skb not submitted and use it for rx DMA */
544 
545 		dxe->ctrl = value;
546 		ctl = ctl->next;
547 		dxe = ctl->desc;
548 	}
549 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_ENCH_ADDR, int_mask);
550 
551 	ch->head_blk_ctl = ctl;
552 	return 0;
553 }
554 
555 void wcn36xx_dxe_rx_frame(struct wcn36xx *wcn)
556 {
557 	int int_src;
558 
559 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_INT_SRC_RAW_REG, &int_src);
560 
561 	/* RX_LOW_PRI */
562 	if (int_src & WCN36XX_DXE_INT_CH1_MASK) {
563 		wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_0_INT_CLR,
564 					   WCN36XX_DXE_INT_CH1_MASK);
565 		wcn36xx_rx_handle_packets(wcn, &(wcn->dxe_rx_l_ch));
566 	}
567 
568 	/* RX_HIGH_PRI */
569 	if (int_src & WCN36XX_DXE_INT_CH3_MASK) {
570 		/* Clean up all the INT within this channel */
571 		wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_0_INT_CLR,
572 					   WCN36XX_DXE_INT_CH3_MASK);
573 		wcn36xx_rx_handle_packets(wcn, &(wcn->dxe_rx_h_ch));
574 	}
575 
576 	if (!int_src)
577 		wcn36xx_warn("No DXE interrupt pending\n");
578 }
579 
580 int wcn36xx_dxe_allocate_mem_pools(struct wcn36xx *wcn)
581 {
582 	size_t s;
583 	void *cpu_addr;
584 
585 	/* Allocate BD headers for MGMT frames */
586 
587 	/* Where this come from ask QC */
588 	wcn->mgmt_mem_pool.chunk_size =	WCN36XX_BD_CHUNK_SIZE +
589 		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
590 
591 	s = wcn->mgmt_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_H;
592 	cpu_addr = dma_alloc_coherent(wcn->dev, s, &wcn->mgmt_mem_pool.phy_addr,
593 				      GFP_KERNEL);
594 	if (!cpu_addr)
595 		goto out_err;
596 
597 	wcn->mgmt_mem_pool.virt_addr = cpu_addr;
598 	memset(cpu_addr, 0, s);
599 
600 	/* Allocate BD headers for DATA frames */
601 
602 	/* Where this come from ask QC */
603 	wcn->data_mem_pool.chunk_size = WCN36XX_BD_CHUNK_SIZE +
604 		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
605 
606 	s = wcn->data_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_L;
607 	cpu_addr = dma_alloc_coherent(wcn->dev, s, &wcn->data_mem_pool.phy_addr,
608 				      GFP_KERNEL);
609 	if (!cpu_addr)
610 		goto out_err;
611 
612 	wcn->data_mem_pool.virt_addr = cpu_addr;
613 	memset(cpu_addr, 0, s);
614 
615 	return 0;
616 
617 out_err:
618 	wcn36xx_dxe_free_mem_pools(wcn);
619 	wcn36xx_err("Failed to allocate BD mempool\n");
620 	return -ENOMEM;
621 }
622 
623 void wcn36xx_dxe_free_mem_pools(struct wcn36xx *wcn)
624 {
625 	if (wcn->mgmt_mem_pool.virt_addr)
626 		dma_free_coherent(wcn->dev, wcn->mgmt_mem_pool.chunk_size *
627 				  WCN36XX_DXE_CH_DESC_NUMB_TX_H,
628 				  wcn->mgmt_mem_pool.virt_addr,
629 				  wcn->mgmt_mem_pool.phy_addr);
630 
631 	if (wcn->data_mem_pool.virt_addr) {
632 		dma_free_coherent(wcn->dev, wcn->data_mem_pool.chunk_size *
633 				  WCN36XX_DXE_CH_DESC_NUMB_TX_L,
634 				  wcn->data_mem_pool.virt_addr,
635 				  wcn->data_mem_pool.phy_addr);
636 	}
637 }
638 
639 int wcn36xx_dxe_tx_frame(struct wcn36xx *wcn,
640 			 struct wcn36xx_vif *vif_priv,
641 			 struct wcn36xx_tx_bd *bd,
642 			 struct sk_buff *skb,
643 			 bool is_low)
644 {
645 	struct wcn36xx_dxe_ctl *ctl = NULL;
646 	struct wcn36xx_dxe_desc *desc = NULL;
647 	struct wcn36xx_dxe_ch *ch = NULL;
648 	unsigned long flags;
649 	int ret;
650 
651 	ch = is_low ? &wcn->dxe_tx_l_ch : &wcn->dxe_tx_h_ch;
652 
653 	spin_lock_irqsave(&ch->lock, flags);
654 	ctl = ch->head_blk_ctl;
655 
656 	/*
657 	 * If skb is not null that means that we reached the tail of the ring
658 	 * hence ring is full. Stop queues to let mac80211 back off until ring
659 	 * has an empty slot again.
660 	 */
661 	if (NULL != ctl->next->skb) {
662 		ieee80211_stop_queues(wcn->hw);
663 		wcn->queues_stopped = true;
664 		spin_unlock_irqrestore(&ch->lock, flags);
665 		return -EBUSY;
666 	}
667 
668 	ctl->skb = NULL;
669 	desc = ctl->desc;
670 
671 	/* write buffer descriptor */
672 	memcpy(ctl->bd_cpu_addr, bd, sizeof(*bd));
673 
674 	/* Set source address of the BD we send */
675 	desc->src_addr_l = ctl->bd_phy_addr;
676 
677 	desc->dst_addr_l = ch->dxe_wq;
678 	desc->fr_len = sizeof(struct wcn36xx_tx_bd);
679 	desc->ctrl = ch->ctrl_bd;
680 
681 	wcn36xx_dbg(WCN36XX_DBG_DXE, "DXE TX\n");
682 
683 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "DESC1 >>> ",
684 			 (char *)desc, sizeof(*desc));
685 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP,
686 			 "BD   >>> ", (char *)ctl->bd_cpu_addr,
687 			 sizeof(struct wcn36xx_tx_bd));
688 
689 	/* Set source address of the SKB we send */
690 	ctl = ctl->next;
691 	desc = ctl->desc;
692 	if (ctl->bd_cpu_addr) {
693 		wcn36xx_err("bd_cpu_addr cannot be NULL for skb DXE\n");
694 		ret = -EINVAL;
695 		goto unlock;
696 	}
697 
698 	desc->src_addr_l = dma_map_single(wcn->dev,
699 					  skb->data,
700 					  skb->len,
701 					  DMA_TO_DEVICE);
702 	if (dma_mapping_error(wcn->dev, desc->src_addr_l)) {
703 		dev_err(wcn->dev, "unable to DMA map src_addr_l\n");
704 		ret = -ENOMEM;
705 		goto unlock;
706 	}
707 
708 	ctl->skb = skb;
709 	desc->dst_addr_l = ch->dxe_wq;
710 	desc->fr_len = ctl->skb->len;
711 
712 	/* set dxe descriptor to VALID */
713 	desc->ctrl = ch->ctrl_skb;
714 
715 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "DESC2 >>> ",
716 			 (char *)desc, sizeof(*desc));
717 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "SKB   >>> ",
718 			 (char *)ctl->skb->data, ctl->skb->len);
719 
720 	/* Move the head of the ring to the next empty descriptor */
721 	 ch->head_blk_ctl = ctl->next;
722 
723 	/*
724 	 * When connected and trying to send data frame chip can be in sleep
725 	 * mode and writing to the register will not wake up the chip. Instead
726 	 * notify chip about new frame through SMSM bus.
727 	 */
728 	if (is_low &&  vif_priv->pw_state == WCN36XX_BMPS) {
729 		qcom_smem_state_update_bits(wcn->tx_rings_empty_state,
730 					    WCN36XX_SMSM_WLAN_TX_ENABLE,
731 					    WCN36XX_SMSM_WLAN_TX_ENABLE);
732 	} else {
733 		/* indicate End Of Packet and generate interrupt on descriptor
734 		 * done.
735 		 */
736 		wcn36xx_dxe_write_register(wcn,
737 			ch->reg_ctrl, ch->def_ctrl);
738 	}
739 
740 	ret = 0;
741 unlock:
742 	spin_unlock_irqrestore(&ch->lock, flags);
743 	return ret;
744 }
745 
746 int wcn36xx_dxe_init(struct wcn36xx *wcn)
747 {
748 	int reg_data = 0, ret;
749 
750 	reg_data = WCN36XX_DXE_REG_RESET;
751 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_REG_CSR_RESET, reg_data);
752 
753 	/* Select channels for rx avail and xfer done interrupts... */
754 	reg_data = (WCN36XX_DXE_INT_CH3_MASK | WCN36XX_DXE_INT_CH1_MASK) << 16 |
755 		    WCN36XX_DXE_INT_CH0_MASK | WCN36XX_DXE_INT_CH4_MASK;
756 	if (wcn->is_pronto)
757 		wcn36xx_ccu_write_register(wcn, WCN36XX_CCU_DXE_INT_SELECT_PRONTO, reg_data);
758 	else
759 		wcn36xx_ccu_write_register(wcn, WCN36XX_CCU_DXE_INT_SELECT_RIVA, reg_data);
760 
761 	/***************************************/
762 	/* Init descriptors for TX LOW channel */
763 	/***************************************/
764 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_tx_l_ch);
765 	if (ret) {
766 		dev_err(wcn->dev, "Error allocating descriptor\n");
767 		return ret;
768 	}
769 	wcn36xx_dxe_init_tx_bd(&wcn->dxe_tx_l_ch, &wcn->data_mem_pool);
770 
771 	/* Write channel head to a NEXT register */
772 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_TX_L,
773 		wcn->dxe_tx_l_ch.head_blk_ctl->desc_phy_addr);
774 
775 	/* Program DMA destination addr for TX LOW */
776 	wcn36xx_dxe_write_register(wcn,
777 		WCN36XX_DXE_CH_DEST_ADDR_TX_L,
778 		WCN36XX_DXE_WQ_TX_L);
779 
780 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_REG_CH_EN, &reg_data);
781 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_TX_L);
782 
783 	/***************************************/
784 	/* Init descriptors for TX HIGH channel */
785 	/***************************************/
786 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_tx_h_ch);
787 	if (ret) {
788 		dev_err(wcn->dev, "Error allocating descriptor\n");
789 		goto out_err_txh_ch;
790 	}
791 
792 	wcn36xx_dxe_init_tx_bd(&wcn->dxe_tx_h_ch, &wcn->mgmt_mem_pool);
793 
794 	/* Write channel head to a NEXT register */
795 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_TX_H,
796 		wcn->dxe_tx_h_ch.head_blk_ctl->desc_phy_addr);
797 
798 	/* Program DMA destination addr for TX HIGH */
799 	wcn36xx_dxe_write_register(wcn,
800 		WCN36XX_DXE_CH_DEST_ADDR_TX_H,
801 		WCN36XX_DXE_WQ_TX_H);
802 
803 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_REG_CH_EN, &reg_data);
804 
805 	/* Enable channel interrupts */
806 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_TX_H);
807 
808 	/***************************************/
809 	/* Init descriptors for RX LOW channel */
810 	/***************************************/
811 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_rx_l_ch);
812 	if (ret) {
813 		dev_err(wcn->dev, "Error allocating descriptor\n");
814 		goto out_err_rxl_ch;
815 	}
816 
817 
818 	/* For RX we need to preallocated buffers */
819 	wcn36xx_dxe_ch_alloc_skb(wcn, &wcn->dxe_rx_l_ch);
820 
821 	/* Write channel head to a NEXT register */
822 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_RX_L,
823 		wcn->dxe_rx_l_ch.head_blk_ctl->desc_phy_addr);
824 
825 	/* Write DMA source address */
826 	wcn36xx_dxe_write_register(wcn,
827 		WCN36XX_DXE_CH_SRC_ADDR_RX_L,
828 		WCN36XX_DXE_WQ_RX_L);
829 
830 	/* Program preallocated destination address */
831 	wcn36xx_dxe_write_register(wcn,
832 		WCN36XX_DXE_CH_DEST_ADDR_RX_L,
833 		wcn->dxe_rx_l_ch.head_blk_ctl->desc->phy_next_l);
834 
835 	/* Enable default control registers */
836 	wcn36xx_dxe_write_register(wcn,
837 		WCN36XX_DXE_REG_CTL_RX_L,
838 		WCN36XX_DXE_CH_DEFAULT_CTL_RX_L);
839 
840 	/* Enable channel interrupts */
841 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_L);
842 
843 	/***************************************/
844 	/* Init descriptors for RX HIGH channel */
845 	/***************************************/
846 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_rx_h_ch);
847 	if (ret) {
848 		dev_err(wcn->dev, "Error allocating descriptor\n");
849 		goto out_err_rxh_ch;
850 	}
851 
852 	/* For RX we need to prealocat buffers */
853 	wcn36xx_dxe_ch_alloc_skb(wcn, &wcn->dxe_rx_h_ch);
854 
855 	/* Write chanel head to a NEXT register */
856 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_RX_H,
857 		wcn->dxe_rx_h_ch.head_blk_ctl->desc_phy_addr);
858 
859 	/* Write DMA source address */
860 	wcn36xx_dxe_write_register(wcn,
861 		WCN36XX_DXE_CH_SRC_ADDR_RX_H,
862 		WCN36XX_DXE_WQ_RX_H);
863 
864 	/* Program preallocated destination address */
865 	wcn36xx_dxe_write_register(wcn,
866 		WCN36XX_DXE_CH_DEST_ADDR_RX_H,
867 		 wcn->dxe_rx_h_ch.head_blk_ctl->desc->phy_next_l);
868 
869 	/* Enable default control registers */
870 	wcn36xx_dxe_write_register(wcn,
871 		WCN36XX_DXE_REG_CTL_RX_H,
872 		WCN36XX_DXE_CH_DEFAULT_CTL_RX_H);
873 
874 	/* Enable channel interrupts */
875 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_H);
876 
877 	ret = wcn36xx_dxe_request_irqs(wcn);
878 	if (ret < 0)
879 		goto out_err_irq;
880 
881 	return 0;
882 
883 out_err_irq:
884 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_rx_h_ch);
885 out_err_rxh_ch:
886 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_rx_l_ch);
887 out_err_rxl_ch:
888 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_tx_h_ch);
889 out_err_txh_ch:
890 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_tx_l_ch);
891 
892 	return ret;
893 }
894 
895 void wcn36xx_dxe_deinit(struct wcn36xx *wcn)
896 {
897 	free_irq(wcn->tx_irq, wcn);
898 	free_irq(wcn->rx_irq, wcn);
899 
900 	if (wcn->tx_ack_skb) {
901 		ieee80211_tx_status_irqsafe(wcn->hw, wcn->tx_ack_skb);
902 		wcn->tx_ack_skb = NULL;
903 	}
904 
905 	wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_l_ch);
906 	wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_h_ch);
907 }
908