xref: /linux/drivers/net/wireless/ath/wcn36xx/dxe.c (revision d793fb46822ff7408a1767313ef6b12e811baa55)
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_zalloc_coherent(dev, size,
178 					       &wcn_ch->dma_addr,
179 					       GFP_KERNEL);
180 	if (!wcn_ch->cpu_addr)
181 		return -ENOMEM;
182 
183 	cur_dxe = (struct wcn36xx_dxe_desc *)wcn_ch->cpu_addr;
184 	cur_ctl = wcn_ch->head_blk_ctl;
185 
186 	for (i = 0; i < wcn_ch->desc_num; i++) {
187 		cur_ctl->desc = cur_dxe;
188 		cur_ctl->desc_phy_addr = wcn_ch->dma_addr +
189 			i * sizeof(struct wcn36xx_dxe_desc);
190 
191 		switch (wcn_ch->ch_type) {
192 		case WCN36XX_DXE_CH_TX_L:
193 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_TX_L;
194 			cur_dxe->dst_addr_l = WCN36XX_DXE_WQ_TX_L;
195 			break;
196 		case WCN36XX_DXE_CH_TX_H:
197 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_TX_H;
198 			cur_dxe->dst_addr_l = WCN36XX_DXE_WQ_TX_H;
199 			break;
200 		case WCN36XX_DXE_CH_RX_L:
201 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_RX_L;
202 			cur_dxe->src_addr_l = WCN36XX_DXE_WQ_RX_L;
203 			break;
204 		case WCN36XX_DXE_CH_RX_H:
205 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_RX_H;
206 			cur_dxe->src_addr_l = WCN36XX_DXE_WQ_RX_H;
207 			break;
208 		}
209 		if (0 == i) {
210 			cur_dxe->phy_next_l = 0;
211 		} else if ((0 < i) && (i < wcn_ch->desc_num - 1)) {
212 			prev_dxe->phy_next_l =
213 				cur_ctl->desc_phy_addr;
214 		} else if (i == (wcn_ch->desc_num - 1)) {
215 			prev_dxe->phy_next_l =
216 				cur_ctl->desc_phy_addr;
217 			cur_dxe->phy_next_l =
218 				wcn_ch->head_blk_ctl->desc_phy_addr;
219 		}
220 		cur_ctl = cur_ctl->next;
221 		prev_dxe = cur_dxe;
222 		cur_dxe++;
223 	}
224 
225 	return 0;
226 }
227 
228 static void wcn36xx_dxe_deinit_descs(struct device *dev, struct wcn36xx_dxe_ch *wcn_ch)
229 {
230 	size_t size;
231 
232 	size = wcn_ch->desc_num * sizeof(struct wcn36xx_dxe_desc);
233 	dma_free_coherent(dev, size,wcn_ch->cpu_addr, wcn_ch->dma_addr);
234 }
235 
236 static void wcn36xx_dxe_init_tx_bd(struct wcn36xx_dxe_ch *ch,
237 				   struct wcn36xx_dxe_mem_pool *pool)
238 {
239 	int i, chunk_size = pool->chunk_size;
240 	dma_addr_t bd_phy_addr = pool->phy_addr;
241 	void *bd_cpu_addr = pool->virt_addr;
242 	struct wcn36xx_dxe_ctl *cur = ch->head_blk_ctl;
243 
244 	for (i = 0; i < ch->desc_num; i++) {
245 		/* Only every second dxe needs a bd pointer,
246 		   the other will point to the skb data */
247 		if (!(i & 1)) {
248 			cur->bd_phy_addr = bd_phy_addr;
249 			cur->bd_cpu_addr = bd_cpu_addr;
250 			bd_phy_addr += chunk_size;
251 			bd_cpu_addr += chunk_size;
252 		} else {
253 			cur->bd_phy_addr = 0;
254 			cur->bd_cpu_addr = NULL;
255 		}
256 		cur = cur->next;
257 	}
258 }
259 
260 static int wcn36xx_dxe_enable_ch_int(struct wcn36xx *wcn, u16 wcn_ch)
261 {
262 	int reg_data = 0;
263 
264 	wcn36xx_dxe_read_register(wcn,
265 				  WCN36XX_DXE_INT_MASK_REG,
266 				  &reg_data);
267 
268 	reg_data |= wcn_ch;
269 
270 	wcn36xx_dxe_write_register(wcn,
271 				   WCN36XX_DXE_INT_MASK_REG,
272 				   (int)reg_data);
273 	return 0;
274 }
275 
276 static int wcn36xx_dxe_fill_skb(struct device *dev,
277 				struct wcn36xx_dxe_ctl *ctl,
278 				gfp_t gfp)
279 {
280 	struct wcn36xx_dxe_desc *dxe = ctl->desc;
281 	struct sk_buff *skb;
282 
283 	skb = alloc_skb(WCN36XX_PKT_SIZE, gfp);
284 	if (skb == NULL)
285 		return -ENOMEM;
286 
287 	dxe->dst_addr_l = dma_map_single(dev,
288 					 skb_tail_pointer(skb),
289 					 WCN36XX_PKT_SIZE,
290 					 DMA_FROM_DEVICE);
291 	if (dma_mapping_error(dev, dxe->dst_addr_l)) {
292 		dev_err(dev, "unable to map skb\n");
293 		kfree_skb(skb);
294 		return -ENOMEM;
295 	}
296 	ctl->skb = skb;
297 
298 	return 0;
299 }
300 
301 static int wcn36xx_dxe_ch_alloc_skb(struct wcn36xx *wcn,
302 				    struct wcn36xx_dxe_ch *wcn_ch)
303 {
304 	int i;
305 	struct wcn36xx_dxe_ctl *cur_ctl = NULL;
306 
307 	cur_ctl = wcn_ch->head_blk_ctl;
308 
309 	for (i = 0; i < wcn_ch->desc_num; i++) {
310 		wcn36xx_dxe_fill_skb(wcn->dev, cur_ctl, GFP_KERNEL);
311 		cur_ctl = cur_ctl->next;
312 	}
313 
314 	return 0;
315 }
316 
317 static void wcn36xx_dxe_ch_free_skbs(struct wcn36xx *wcn,
318 				     struct wcn36xx_dxe_ch *wcn_ch)
319 {
320 	struct wcn36xx_dxe_ctl *cur = wcn_ch->head_blk_ctl;
321 	int i;
322 
323 	for (i = 0; i < wcn_ch->desc_num; i++) {
324 		kfree_skb(cur->skb);
325 		cur = cur->next;
326 	}
327 }
328 
329 void wcn36xx_dxe_tx_ack_ind(struct wcn36xx *wcn, u32 status)
330 {
331 	struct ieee80211_tx_info *info;
332 	struct sk_buff *skb;
333 	unsigned long flags;
334 
335 	spin_lock_irqsave(&wcn->dxe_lock, flags);
336 	skb = wcn->tx_ack_skb;
337 	wcn->tx_ack_skb = NULL;
338 	spin_unlock_irqrestore(&wcn->dxe_lock, flags);
339 
340 	if (!skb) {
341 		wcn36xx_warn("Spurious TX complete indication\n");
342 		return;
343 	}
344 
345 	info = IEEE80211_SKB_CB(skb);
346 
347 	if (status == 1)
348 		info->flags |= IEEE80211_TX_STAT_ACK;
349 
350 	wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ack status: %d\n", status);
351 
352 	ieee80211_tx_status_irqsafe(wcn->hw, skb);
353 	ieee80211_wake_queues(wcn->hw);
354 }
355 
356 static void reap_tx_dxes(struct wcn36xx *wcn, struct wcn36xx_dxe_ch *ch)
357 {
358 	struct wcn36xx_dxe_ctl *ctl;
359 	struct ieee80211_tx_info *info;
360 	unsigned long flags;
361 
362 	/*
363 	 * Make at least one loop of do-while because in case ring is
364 	 * completely full head and tail are pointing to the same element
365 	 * and while-do will not make any cycles.
366 	 */
367 	spin_lock_irqsave(&ch->lock, flags);
368 	ctl = ch->tail_blk_ctl;
369 	do {
370 		if (READ_ONCE(ctl->desc->ctrl) & WCN36xx_DXE_CTRL_VLD)
371 			break;
372 
373 		if (ctl->skb &&
374 		    READ_ONCE(ctl->desc->ctrl) & WCN36xx_DXE_CTRL_EOP) {
375 			dma_unmap_single(wcn->dev, ctl->desc->src_addr_l,
376 					 ctl->skb->len, DMA_TO_DEVICE);
377 			info = IEEE80211_SKB_CB(ctl->skb);
378 			if (!(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS)) {
379 				/* Keep frame until TX status comes */
380 				ieee80211_free_txskb(wcn->hw, ctl->skb);
381 			}
382 
383 			if (wcn->queues_stopped) {
384 				wcn->queues_stopped = false;
385 				ieee80211_wake_queues(wcn->hw);
386 			}
387 
388 			ctl->skb = NULL;
389 		}
390 		ctl = ctl->next;
391 	} while (ctl != ch->head_blk_ctl);
392 
393 	ch->tail_blk_ctl = ctl;
394 	spin_unlock_irqrestore(&ch->lock, flags);
395 }
396 
397 static irqreturn_t wcn36xx_irq_tx_complete(int irq, void *dev)
398 {
399 	struct wcn36xx *wcn = (struct wcn36xx *)dev;
400 	int int_src, int_reason;
401 
402 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_INT_SRC_RAW_REG, &int_src);
403 
404 	if (int_src & WCN36XX_INT_MASK_CHAN_TX_H) {
405 		wcn36xx_dxe_read_register(wcn,
406 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_TX_H,
407 					  &int_reason);
408 
409 		wcn36xx_dxe_write_register(wcn,
410 					   WCN36XX_DXE_0_INT_CLR,
411 					   WCN36XX_INT_MASK_CHAN_TX_H);
412 
413 		if (int_reason & WCN36XX_CH_STAT_INT_ERR_MASK ) {
414 			wcn36xx_dxe_write_register(wcn,
415 						   WCN36XX_DXE_0_INT_ERR_CLR,
416 						   WCN36XX_INT_MASK_CHAN_TX_H);
417 
418 			wcn36xx_err("DXE IRQ reported error: 0x%x in high TX channel\n",
419 					int_src);
420 		}
421 
422 		if (int_reason & WCN36XX_CH_STAT_INT_DONE_MASK) {
423 			wcn36xx_dxe_write_register(wcn,
424 						   WCN36XX_DXE_0_INT_DONE_CLR,
425 						   WCN36XX_INT_MASK_CHAN_TX_H);
426 		}
427 
428 		if (int_reason & WCN36XX_CH_STAT_INT_ED_MASK) {
429 			wcn36xx_dxe_write_register(wcn,
430 						   WCN36XX_DXE_0_INT_ED_CLR,
431 						   WCN36XX_INT_MASK_CHAN_TX_H);
432 		}
433 
434 		wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ready high, reason %08x\n",
435 			    int_reason);
436 
437 		if (int_reason & (WCN36XX_CH_STAT_INT_DONE_MASK |
438 				  WCN36XX_CH_STAT_INT_ED_MASK))
439 			reap_tx_dxes(wcn, &wcn->dxe_tx_h_ch);
440 	}
441 
442 	if (int_src & WCN36XX_INT_MASK_CHAN_TX_L) {
443 		wcn36xx_dxe_read_register(wcn,
444 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_TX_L,
445 					  &int_reason);
446 
447 		wcn36xx_dxe_write_register(wcn,
448 					   WCN36XX_DXE_0_INT_CLR,
449 					   WCN36XX_INT_MASK_CHAN_TX_L);
450 
451 
452 		if (int_reason & WCN36XX_CH_STAT_INT_ERR_MASK ) {
453 			wcn36xx_dxe_write_register(wcn,
454 						   WCN36XX_DXE_0_INT_ERR_CLR,
455 						   WCN36XX_INT_MASK_CHAN_TX_L);
456 
457 			wcn36xx_err("DXE IRQ reported error: 0x%x in low TX channel\n",
458 					int_src);
459 		}
460 
461 		if (int_reason & WCN36XX_CH_STAT_INT_DONE_MASK) {
462 			wcn36xx_dxe_write_register(wcn,
463 						   WCN36XX_DXE_0_INT_DONE_CLR,
464 						   WCN36XX_INT_MASK_CHAN_TX_L);
465 		}
466 
467 		if (int_reason & WCN36XX_CH_STAT_INT_ED_MASK) {
468 			wcn36xx_dxe_write_register(wcn,
469 						   WCN36XX_DXE_0_INT_ED_CLR,
470 						   WCN36XX_INT_MASK_CHAN_TX_L);
471 		}
472 
473 		wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ready low, reason %08x\n",
474 			    int_reason);
475 
476 		if (int_reason & (WCN36XX_CH_STAT_INT_DONE_MASK |
477 				  WCN36XX_CH_STAT_INT_ED_MASK))
478 			reap_tx_dxes(wcn, &wcn->dxe_tx_l_ch);
479 	}
480 
481 	return IRQ_HANDLED;
482 }
483 
484 static irqreturn_t wcn36xx_irq_rx_ready(int irq, void *dev)
485 {
486 	struct wcn36xx *wcn = (struct wcn36xx *)dev;
487 
488 	wcn36xx_dxe_rx_frame(wcn);
489 
490 	return IRQ_HANDLED;
491 }
492 
493 static int wcn36xx_dxe_request_irqs(struct wcn36xx *wcn)
494 {
495 	int ret;
496 
497 	ret = request_irq(wcn->tx_irq, wcn36xx_irq_tx_complete,
498 			  IRQF_TRIGGER_HIGH, "wcn36xx_tx", wcn);
499 	if (ret) {
500 		wcn36xx_err("failed to alloc tx irq\n");
501 		goto out_err;
502 	}
503 
504 	ret = request_irq(wcn->rx_irq, wcn36xx_irq_rx_ready, IRQF_TRIGGER_HIGH,
505 			  "wcn36xx_rx", wcn);
506 	if (ret) {
507 		wcn36xx_err("failed to alloc rx irq\n");
508 		goto out_txirq;
509 	}
510 
511 	enable_irq_wake(wcn->rx_irq);
512 
513 	return 0;
514 
515 out_txirq:
516 	free_irq(wcn->tx_irq, wcn);
517 out_err:
518 	return ret;
519 
520 }
521 
522 static int wcn36xx_rx_handle_packets(struct wcn36xx *wcn,
523 				     struct wcn36xx_dxe_ch *ch,
524 				     u32 ctrl,
525 				     u32 en_mask,
526 				     u32 int_mask,
527 				     u32 status_reg)
528 {
529 	struct wcn36xx_dxe_desc *dxe;
530 	struct wcn36xx_dxe_ctl *ctl;
531 	dma_addr_t  dma_addr;
532 	struct sk_buff *skb;
533 	u32 int_reason;
534 	int ret;
535 
536 	wcn36xx_dxe_read_register(wcn, status_reg, &int_reason);
537 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_0_INT_CLR, int_mask);
538 
539 	if (int_reason & WCN36XX_CH_STAT_INT_ERR_MASK) {
540 		wcn36xx_dxe_write_register(wcn,
541 					   WCN36XX_DXE_0_INT_ERR_CLR,
542 					   int_mask);
543 
544 		wcn36xx_err("DXE IRQ reported error on RX channel\n");
545 	}
546 
547 	if (int_reason & WCN36XX_CH_STAT_INT_DONE_MASK)
548 		wcn36xx_dxe_write_register(wcn,
549 					   WCN36XX_DXE_0_INT_DONE_CLR,
550 					   int_mask);
551 
552 	if (int_reason & WCN36XX_CH_STAT_INT_ED_MASK)
553 		wcn36xx_dxe_write_register(wcn,
554 					   WCN36XX_DXE_0_INT_ED_CLR,
555 					   int_mask);
556 
557 	if (!(int_reason & (WCN36XX_CH_STAT_INT_DONE_MASK |
558 			    WCN36XX_CH_STAT_INT_ED_MASK)))
559 		return 0;
560 
561 	spin_lock(&ch->lock);
562 
563 	ctl = ch->head_blk_ctl;
564 	dxe = ctl->desc;
565 
566 	while (!(READ_ONCE(dxe->ctrl) & WCN36xx_DXE_CTRL_VLD)) {
567 		skb = ctl->skb;
568 		dma_addr = dxe->dst_addr_l;
569 		ret = wcn36xx_dxe_fill_skb(wcn->dev, ctl, GFP_ATOMIC);
570 		if (0 == ret) {
571 			/* new skb allocation ok. Use the new one and queue
572 			 * the old one to network system.
573 			 */
574 			dma_unmap_single(wcn->dev, dma_addr, WCN36XX_PKT_SIZE,
575 					DMA_FROM_DEVICE);
576 			wcn36xx_rx_skb(wcn, skb);
577 		} /* else keep old skb not submitted and use it for rx DMA */
578 
579 		dxe->ctrl = ctrl;
580 		ctl = ctl->next;
581 		dxe = ctl->desc;
582 	}
583 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_ENCH_ADDR, en_mask);
584 
585 	ch->head_blk_ctl = ctl;
586 
587 	spin_unlock(&ch->lock);
588 
589 	return 0;
590 }
591 
592 void wcn36xx_dxe_rx_frame(struct wcn36xx *wcn)
593 {
594 	int int_src;
595 
596 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_INT_SRC_RAW_REG, &int_src);
597 
598 	/* RX_LOW_PRI */
599 	if (int_src & WCN36XX_DXE_INT_CH1_MASK)
600 		wcn36xx_rx_handle_packets(wcn, &wcn->dxe_rx_l_ch,
601 					  WCN36XX_DXE_CTRL_RX_L,
602 					  WCN36XX_DXE_INT_CH1_MASK,
603 					  WCN36XX_INT_MASK_CHAN_RX_L,
604 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_RX_L);
605 
606 	/* RX_HIGH_PRI */
607 	if (int_src & WCN36XX_DXE_INT_CH3_MASK)
608 		wcn36xx_rx_handle_packets(wcn, &wcn->dxe_rx_h_ch,
609 					  WCN36XX_DXE_CTRL_RX_H,
610 					  WCN36XX_DXE_INT_CH3_MASK,
611 					  WCN36XX_INT_MASK_CHAN_RX_H,
612 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_RX_H);
613 
614 	if (!int_src)
615 		wcn36xx_warn("No DXE interrupt pending\n");
616 }
617 
618 int wcn36xx_dxe_allocate_mem_pools(struct wcn36xx *wcn)
619 {
620 	size_t s;
621 	void *cpu_addr;
622 
623 	/* Allocate BD headers for MGMT frames */
624 
625 	/* Where this come from ask QC */
626 	wcn->mgmt_mem_pool.chunk_size =	WCN36XX_BD_CHUNK_SIZE +
627 		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
628 
629 	s = wcn->mgmt_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_H;
630 	cpu_addr = dma_zalloc_coherent(wcn->dev, s,
631 				       &wcn->mgmt_mem_pool.phy_addr,
632 				       GFP_KERNEL);
633 	if (!cpu_addr)
634 		goto out_err;
635 
636 	wcn->mgmt_mem_pool.virt_addr = cpu_addr;
637 
638 	/* Allocate BD headers for DATA frames */
639 
640 	/* Where this come from ask QC */
641 	wcn->data_mem_pool.chunk_size = WCN36XX_BD_CHUNK_SIZE +
642 		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
643 
644 	s = wcn->data_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_L;
645 	cpu_addr = dma_zalloc_coherent(wcn->dev, s,
646 				       &wcn->data_mem_pool.phy_addr,
647 				       GFP_KERNEL);
648 	if (!cpu_addr)
649 		goto out_err;
650 
651 	wcn->data_mem_pool.virt_addr = cpu_addr;
652 
653 	return 0;
654 
655 out_err:
656 	wcn36xx_dxe_free_mem_pools(wcn);
657 	wcn36xx_err("Failed to allocate BD mempool\n");
658 	return -ENOMEM;
659 }
660 
661 void wcn36xx_dxe_free_mem_pools(struct wcn36xx *wcn)
662 {
663 	if (wcn->mgmt_mem_pool.virt_addr)
664 		dma_free_coherent(wcn->dev, wcn->mgmt_mem_pool.chunk_size *
665 				  WCN36XX_DXE_CH_DESC_NUMB_TX_H,
666 				  wcn->mgmt_mem_pool.virt_addr,
667 				  wcn->mgmt_mem_pool.phy_addr);
668 
669 	if (wcn->data_mem_pool.virt_addr) {
670 		dma_free_coherent(wcn->dev, wcn->data_mem_pool.chunk_size *
671 				  WCN36XX_DXE_CH_DESC_NUMB_TX_L,
672 				  wcn->data_mem_pool.virt_addr,
673 				  wcn->data_mem_pool.phy_addr);
674 	}
675 }
676 
677 int wcn36xx_dxe_tx_frame(struct wcn36xx *wcn,
678 			 struct wcn36xx_vif *vif_priv,
679 			 struct wcn36xx_tx_bd *bd,
680 			 struct sk_buff *skb,
681 			 bool is_low)
682 {
683 	struct wcn36xx_dxe_desc *desc_bd, *desc_skb;
684 	struct wcn36xx_dxe_ctl *ctl_bd, *ctl_skb;
685 	struct wcn36xx_dxe_ch *ch = NULL;
686 	unsigned long flags;
687 	int ret;
688 
689 	ch = is_low ? &wcn->dxe_tx_l_ch : &wcn->dxe_tx_h_ch;
690 
691 	spin_lock_irqsave(&ch->lock, flags);
692 	ctl_bd = ch->head_blk_ctl;
693 	ctl_skb = ctl_bd->next;
694 
695 	/*
696 	 * If skb is not null that means that we reached the tail of the ring
697 	 * hence ring is full. Stop queues to let mac80211 back off until ring
698 	 * has an empty slot again.
699 	 */
700 	if (NULL != ctl_skb->skb) {
701 		ieee80211_stop_queues(wcn->hw);
702 		wcn->queues_stopped = true;
703 		spin_unlock_irqrestore(&ch->lock, flags);
704 		return -EBUSY;
705 	}
706 
707 	if (unlikely(ctl_skb->bd_cpu_addr)) {
708 		wcn36xx_err("bd_cpu_addr cannot be NULL for skb DXE\n");
709 		ret = -EINVAL;
710 		goto unlock;
711 	}
712 
713 	desc_bd = ctl_bd->desc;
714 	desc_skb = ctl_skb->desc;
715 
716 	ctl_bd->skb = NULL;
717 
718 	/* write buffer descriptor */
719 	memcpy(ctl_bd->bd_cpu_addr, bd, sizeof(*bd));
720 
721 	/* Set source address of the BD we send */
722 	desc_bd->src_addr_l = ctl_bd->bd_phy_addr;
723 	desc_bd->dst_addr_l = ch->dxe_wq;
724 	desc_bd->fr_len = sizeof(struct wcn36xx_tx_bd);
725 
726 	wcn36xx_dbg(WCN36XX_DBG_DXE, "DXE TX\n");
727 
728 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "DESC1 >>> ",
729 			 (char *)desc_bd, sizeof(*desc_bd));
730 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP,
731 			 "BD   >>> ", (char *)ctl_bd->bd_cpu_addr,
732 			 sizeof(struct wcn36xx_tx_bd));
733 
734 	desc_skb->src_addr_l = dma_map_single(wcn->dev,
735 					      skb->data,
736 					      skb->len,
737 					      DMA_TO_DEVICE);
738 	if (dma_mapping_error(wcn->dev, desc_skb->src_addr_l)) {
739 		dev_err(wcn->dev, "unable to DMA map src_addr_l\n");
740 		ret = -ENOMEM;
741 		goto unlock;
742 	}
743 
744 	ctl_skb->skb = skb;
745 	desc_skb->dst_addr_l = ch->dxe_wq;
746 	desc_skb->fr_len = ctl_skb->skb->len;
747 
748 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "DESC2 >>> ",
749 			 (char *)desc_skb, sizeof(*desc_skb));
750 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "SKB   >>> ",
751 			 (char *)ctl_skb->skb->data, ctl_skb->skb->len);
752 
753 	/* Move the head of the ring to the next empty descriptor */
754 	 ch->head_blk_ctl = ctl_skb->next;
755 
756 	/* Commit all previous writes and set descriptors to VALID */
757 	wmb();
758 	desc_skb->ctrl = ch->ctrl_skb;
759 	wmb();
760 	desc_bd->ctrl = ch->ctrl_bd;
761 
762 	/*
763 	 * When connected and trying to send data frame chip can be in sleep
764 	 * mode and writing to the register will not wake up the chip. Instead
765 	 * notify chip about new frame through SMSM bus.
766 	 */
767 	if (is_low &&  vif_priv->pw_state == WCN36XX_BMPS) {
768 		qcom_smem_state_update_bits(wcn->tx_rings_empty_state,
769 					    WCN36XX_SMSM_WLAN_TX_ENABLE,
770 					    WCN36XX_SMSM_WLAN_TX_ENABLE);
771 	} else {
772 		/* indicate End Of Packet and generate interrupt on descriptor
773 		 * done.
774 		 */
775 		wcn36xx_dxe_write_register(wcn,
776 			ch->reg_ctrl, ch->def_ctrl);
777 	}
778 
779 	ret = 0;
780 unlock:
781 	spin_unlock_irqrestore(&ch->lock, flags);
782 	return ret;
783 }
784 
785 int wcn36xx_dxe_init(struct wcn36xx *wcn)
786 {
787 	int reg_data = 0, ret;
788 
789 	reg_data = WCN36XX_DXE_REG_RESET;
790 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_REG_CSR_RESET, reg_data);
791 
792 	/* Select channels for rx avail and xfer done interrupts... */
793 	reg_data = (WCN36XX_DXE_INT_CH3_MASK | WCN36XX_DXE_INT_CH1_MASK) << 16 |
794 		    WCN36XX_DXE_INT_CH0_MASK | WCN36XX_DXE_INT_CH4_MASK;
795 	if (wcn->is_pronto)
796 		wcn36xx_ccu_write_register(wcn, WCN36XX_CCU_DXE_INT_SELECT_PRONTO, reg_data);
797 	else
798 		wcn36xx_ccu_write_register(wcn, WCN36XX_CCU_DXE_INT_SELECT_RIVA, reg_data);
799 
800 	/***************************************/
801 	/* Init descriptors for TX LOW channel */
802 	/***************************************/
803 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_tx_l_ch);
804 	if (ret) {
805 		dev_err(wcn->dev, "Error allocating descriptor\n");
806 		return ret;
807 	}
808 	wcn36xx_dxe_init_tx_bd(&wcn->dxe_tx_l_ch, &wcn->data_mem_pool);
809 
810 	/* Write channel head to a NEXT register */
811 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_TX_L,
812 		wcn->dxe_tx_l_ch.head_blk_ctl->desc_phy_addr);
813 
814 	/* Program DMA destination addr for TX LOW */
815 	wcn36xx_dxe_write_register(wcn,
816 		WCN36XX_DXE_CH_DEST_ADDR_TX_L,
817 		WCN36XX_DXE_WQ_TX_L);
818 
819 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_REG_CH_EN, &reg_data);
820 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_TX_L);
821 
822 	/***************************************/
823 	/* Init descriptors for TX HIGH channel */
824 	/***************************************/
825 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_tx_h_ch);
826 	if (ret) {
827 		dev_err(wcn->dev, "Error allocating descriptor\n");
828 		goto out_err_txh_ch;
829 	}
830 
831 	wcn36xx_dxe_init_tx_bd(&wcn->dxe_tx_h_ch, &wcn->mgmt_mem_pool);
832 
833 	/* Write channel head to a NEXT register */
834 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_TX_H,
835 		wcn->dxe_tx_h_ch.head_blk_ctl->desc_phy_addr);
836 
837 	/* Program DMA destination addr for TX HIGH */
838 	wcn36xx_dxe_write_register(wcn,
839 		WCN36XX_DXE_CH_DEST_ADDR_TX_H,
840 		WCN36XX_DXE_WQ_TX_H);
841 
842 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_REG_CH_EN, &reg_data);
843 
844 	/* Enable channel interrupts */
845 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_TX_H);
846 
847 	/***************************************/
848 	/* Init descriptors for RX LOW channel */
849 	/***************************************/
850 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_rx_l_ch);
851 	if (ret) {
852 		dev_err(wcn->dev, "Error allocating descriptor\n");
853 		goto out_err_rxl_ch;
854 	}
855 
856 
857 	/* For RX we need to preallocated buffers */
858 	wcn36xx_dxe_ch_alloc_skb(wcn, &wcn->dxe_rx_l_ch);
859 
860 	/* Write channel head to a NEXT register */
861 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_RX_L,
862 		wcn->dxe_rx_l_ch.head_blk_ctl->desc_phy_addr);
863 
864 	/* Write DMA source address */
865 	wcn36xx_dxe_write_register(wcn,
866 		WCN36XX_DXE_CH_SRC_ADDR_RX_L,
867 		WCN36XX_DXE_WQ_RX_L);
868 
869 	/* Program preallocated destination address */
870 	wcn36xx_dxe_write_register(wcn,
871 		WCN36XX_DXE_CH_DEST_ADDR_RX_L,
872 		wcn->dxe_rx_l_ch.head_blk_ctl->desc->phy_next_l);
873 
874 	/* Enable default control registers */
875 	wcn36xx_dxe_write_register(wcn,
876 		WCN36XX_DXE_REG_CTL_RX_L,
877 		WCN36XX_DXE_CH_DEFAULT_CTL_RX_L);
878 
879 	/* Enable channel interrupts */
880 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_L);
881 
882 	/***************************************/
883 	/* Init descriptors for RX HIGH channel */
884 	/***************************************/
885 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_rx_h_ch);
886 	if (ret) {
887 		dev_err(wcn->dev, "Error allocating descriptor\n");
888 		goto out_err_rxh_ch;
889 	}
890 
891 	/* For RX we need to prealocat buffers */
892 	wcn36xx_dxe_ch_alloc_skb(wcn, &wcn->dxe_rx_h_ch);
893 
894 	/* Write chanel head to a NEXT register */
895 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_RX_H,
896 		wcn->dxe_rx_h_ch.head_blk_ctl->desc_phy_addr);
897 
898 	/* Write DMA source address */
899 	wcn36xx_dxe_write_register(wcn,
900 		WCN36XX_DXE_CH_SRC_ADDR_RX_H,
901 		WCN36XX_DXE_WQ_RX_H);
902 
903 	/* Program preallocated destination address */
904 	wcn36xx_dxe_write_register(wcn,
905 		WCN36XX_DXE_CH_DEST_ADDR_RX_H,
906 		 wcn->dxe_rx_h_ch.head_blk_ctl->desc->phy_next_l);
907 
908 	/* Enable default control registers */
909 	wcn36xx_dxe_write_register(wcn,
910 		WCN36XX_DXE_REG_CTL_RX_H,
911 		WCN36XX_DXE_CH_DEFAULT_CTL_RX_H);
912 
913 	/* Enable channel interrupts */
914 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_H);
915 
916 	ret = wcn36xx_dxe_request_irqs(wcn);
917 	if (ret < 0)
918 		goto out_err_irq;
919 
920 	return 0;
921 
922 out_err_irq:
923 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_rx_h_ch);
924 out_err_rxh_ch:
925 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_rx_l_ch);
926 out_err_rxl_ch:
927 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_tx_h_ch);
928 out_err_txh_ch:
929 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_tx_l_ch);
930 
931 	return ret;
932 }
933 
934 void wcn36xx_dxe_deinit(struct wcn36xx *wcn)
935 {
936 	free_irq(wcn->tx_irq, wcn);
937 	free_irq(wcn->rx_irq, wcn);
938 
939 	if (wcn->tx_ack_skb) {
940 		ieee80211_tx_status_irqsafe(wcn->hw, wcn->tx_ack_skb);
941 		wcn->tx_ack_skb = NULL;
942 	}
943 
944 	wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_l_ch);
945 	wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_h_ch);
946 }
947