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 	cur_dxe = (struct wcn36xx_dxe_desc *)wcn_ch->cpu_addr;
183 	cur_ctl = wcn_ch->head_blk_ctl;
184 
185 	for (i = 0; i < wcn_ch->desc_num; i++) {
186 		cur_ctl->desc = cur_dxe;
187 		cur_ctl->desc_phy_addr = wcn_ch->dma_addr +
188 			i * sizeof(struct wcn36xx_dxe_desc);
189 
190 		switch (wcn_ch->ch_type) {
191 		case WCN36XX_DXE_CH_TX_L:
192 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_TX_L;
193 			cur_dxe->dst_addr_l = WCN36XX_DXE_WQ_TX_L;
194 			break;
195 		case WCN36XX_DXE_CH_TX_H:
196 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_TX_H;
197 			cur_dxe->dst_addr_l = WCN36XX_DXE_WQ_TX_H;
198 			break;
199 		case WCN36XX_DXE_CH_RX_L:
200 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_RX_L;
201 			cur_dxe->src_addr_l = WCN36XX_DXE_WQ_RX_L;
202 			break;
203 		case WCN36XX_DXE_CH_RX_H:
204 			cur_dxe->ctrl = WCN36XX_DXE_CTRL_RX_H;
205 			cur_dxe->src_addr_l = WCN36XX_DXE_WQ_RX_H;
206 			break;
207 		}
208 		if (0 == i) {
209 			cur_dxe->phy_next_l = 0;
210 		} else if ((0 < i) && (i < wcn_ch->desc_num - 1)) {
211 			prev_dxe->phy_next_l =
212 				cur_ctl->desc_phy_addr;
213 		} else if (i == (wcn_ch->desc_num - 1)) {
214 			prev_dxe->phy_next_l =
215 				cur_ctl->desc_phy_addr;
216 			cur_dxe->phy_next_l =
217 				wcn_ch->head_blk_ctl->desc_phy_addr;
218 		}
219 		cur_ctl = cur_ctl->next;
220 		prev_dxe = cur_dxe;
221 		cur_dxe++;
222 	}
223 
224 	return 0;
225 }
226 
227 static void wcn36xx_dxe_deinit_descs(struct device *dev, struct wcn36xx_dxe_ch *wcn_ch)
228 {
229 	size_t size;
230 
231 	size = wcn_ch->desc_num * sizeof(struct wcn36xx_dxe_desc);
232 	dma_free_coherent(dev, size,wcn_ch->cpu_addr, wcn_ch->dma_addr);
233 }
234 
235 static void wcn36xx_dxe_init_tx_bd(struct wcn36xx_dxe_ch *ch,
236 				   struct wcn36xx_dxe_mem_pool *pool)
237 {
238 	int i, chunk_size = pool->chunk_size;
239 	dma_addr_t bd_phy_addr = pool->phy_addr;
240 	void *bd_cpu_addr = pool->virt_addr;
241 	struct wcn36xx_dxe_ctl *cur = ch->head_blk_ctl;
242 
243 	for (i = 0; i < ch->desc_num; i++) {
244 		/* Only every second dxe needs a bd pointer,
245 		   the other will point to the skb data */
246 		if (!(i & 1)) {
247 			cur->bd_phy_addr = bd_phy_addr;
248 			cur->bd_cpu_addr = bd_cpu_addr;
249 			bd_phy_addr += chunk_size;
250 			bd_cpu_addr += chunk_size;
251 		} else {
252 			cur->bd_phy_addr = 0;
253 			cur->bd_cpu_addr = NULL;
254 		}
255 		cur = cur->next;
256 	}
257 }
258 
259 static int wcn36xx_dxe_enable_ch_int(struct wcn36xx *wcn, u16 wcn_ch)
260 {
261 	int reg_data = 0;
262 
263 	wcn36xx_dxe_read_register(wcn,
264 				  WCN36XX_DXE_INT_MASK_REG,
265 				  &reg_data);
266 
267 	reg_data |= wcn_ch;
268 
269 	wcn36xx_dxe_write_register(wcn,
270 				   WCN36XX_DXE_INT_MASK_REG,
271 				   (int)reg_data);
272 	return 0;
273 }
274 
275 static int wcn36xx_dxe_fill_skb(struct device *dev,
276 				struct wcn36xx_dxe_ctl *ctl,
277 				gfp_t gfp)
278 {
279 	struct wcn36xx_dxe_desc *dxe = ctl->desc;
280 	struct sk_buff *skb;
281 
282 	skb = alloc_skb(WCN36XX_PKT_SIZE, gfp);
283 	if (skb == NULL)
284 		return -ENOMEM;
285 
286 	dxe->dst_addr_l = dma_map_single(dev,
287 					 skb_tail_pointer(skb),
288 					 WCN36XX_PKT_SIZE,
289 					 DMA_FROM_DEVICE);
290 	if (dma_mapping_error(dev, dxe->dst_addr_l)) {
291 		dev_err(dev, "unable to map skb\n");
292 		kfree_skb(skb);
293 		return -ENOMEM;
294 	}
295 	ctl->skb = skb;
296 
297 	return 0;
298 }
299 
300 static int wcn36xx_dxe_ch_alloc_skb(struct wcn36xx *wcn,
301 				    struct wcn36xx_dxe_ch *wcn_ch)
302 {
303 	int i;
304 	struct wcn36xx_dxe_ctl *cur_ctl = NULL;
305 
306 	cur_ctl = wcn_ch->head_blk_ctl;
307 
308 	for (i = 0; i < wcn_ch->desc_num; i++) {
309 		wcn36xx_dxe_fill_skb(wcn->dev, cur_ctl, GFP_KERNEL);
310 		cur_ctl = cur_ctl->next;
311 	}
312 
313 	return 0;
314 }
315 
316 static void wcn36xx_dxe_ch_free_skbs(struct wcn36xx *wcn,
317 				     struct wcn36xx_dxe_ch *wcn_ch)
318 {
319 	struct wcn36xx_dxe_ctl *cur = wcn_ch->head_blk_ctl;
320 	int i;
321 
322 	for (i = 0; i < wcn_ch->desc_num; i++) {
323 		kfree_skb(cur->skb);
324 		cur = cur->next;
325 	}
326 }
327 
328 void wcn36xx_dxe_tx_ack_ind(struct wcn36xx *wcn, u32 status)
329 {
330 	struct ieee80211_tx_info *info;
331 	struct sk_buff *skb;
332 	unsigned long flags;
333 
334 	spin_lock_irqsave(&wcn->dxe_lock, flags);
335 	skb = wcn->tx_ack_skb;
336 	wcn->tx_ack_skb = NULL;
337 	del_timer(&wcn->tx_ack_timer);
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 	else
350 		info->flags &= ~IEEE80211_TX_STAT_ACK;
351 
352 	wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ack status: %d\n", status);
353 
354 	ieee80211_tx_status_irqsafe(wcn->hw, skb);
355 	ieee80211_wake_queues(wcn->hw);
356 }
357 
358 static void wcn36xx_dxe_tx_timer(struct timer_list *t)
359 {
360 	struct wcn36xx *wcn = from_timer(wcn, t, tx_ack_timer);
361 	struct ieee80211_tx_info *info;
362 	unsigned long flags;
363 	struct sk_buff *skb;
364 
365 	/* TX Timeout */
366 	wcn36xx_dbg(WCN36XX_DBG_DXE, "TX timeout\n");
367 
368 	spin_lock_irqsave(&wcn->dxe_lock, flags);
369 	skb = wcn->tx_ack_skb;
370 	wcn->tx_ack_skb = NULL;
371 	spin_unlock_irqrestore(&wcn->dxe_lock, flags);
372 
373 	if (!skb)
374 		return;
375 
376 	info = IEEE80211_SKB_CB(skb);
377 	info->flags &= ~IEEE80211_TX_STAT_ACK;
378 	info->flags &= ~IEEE80211_TX_STAT_NOACK_TRANSMITTED;
379 
380 	ieee80211_tx_status_irqsafe(wcn->hw, skb);
381 	ieee80211_wake_queues(wcn->hw);
382 }
383 
384 static void reap_tx_dxes(struct wcn36xx *wcn, struct wcn36xx_dxe_ch *ch)
385 {
386 	struct wcn36xx_dxe_ctl *ctl;
387 	struct ieee80211_tx_info *info;
388 	unsigned long flags;
389 
390 	/*
391 	 * Make at least one loop of do-while because in case ring is
392 	 * completely full head and tail are pointing to the same element
393 	 * and while-do will not make any cycles.
394 	 */
395 	spin_lock_irqsave(&ch->lock, flags);
396 	ctl = ch->tail_blk_ctl;
397 	do {
398 		if (READ_ONCE(ctl->desc->ctrl) & WCN36xx_DXE_CTRL_VLD)
399 			break;
400 
401 		if (ctl->skb &&
402 		    READ_ONCE(ctl->desc->ctrl) & WCN36xx_DXE_CTRL_EOP) {
403 			dma_unmap_single(wcn->dev, ctl->desc->src_addr_l,
404 					 ctl->skb->len, DMA_TO_DEVICE);
405 			info = IEEE80211_SKB_CB(ctl->skb);
406 			if (info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS) {
407 				if (info->flags & IEEE80211_TX_CTL_NO_ACK) {
408 					info->flags |= IEEE80211_TX_STAT_NOACK_TRANSMITTED;
409 					ieee80211_tx_status_irqsafe(wcn->hw, ctl->skb);
410 				} else {
411 					/* Wait for the TX ack indication or timeout... */
412 					spin_lock(&wcn->dxe_lock);
413 					if (WARN_ON(wcn->tx_ack_skb))
414 						ieee80211_free_txskb(wcn->hw, wcn->tx_ack_skb);
415 					wcn->tx_ack_skb = ctl->skb; /* Tracking ref */
416 					mod_timer(&wcn->tx_ack_timer, jiffies + HZ / 10);
417 					spin_unlock(&wcn->dxe_lock);
418 				}
419 				/* do not free, ownership transferred to mac80211 status cb */
420 			} else {
421 				ieee80211_free_txskb(wcn->hw, ctl->skb);
422 			}
423 
424 			if (wcn->queues_stopped) {
425 				wcn->queues_stopped = false;
426 				ieee80211_wake_queues(wcn->hw);
427 			}
428 
429 			ctl->skb = NULL;
430 		}
431 		ctl = ctl->next;
432 	} while (ctl != ch->head_blk_ctl);
433 
434 	ch->tail_blk_ctl = ctl;
435 	spin_unlock_irqrestore(&ch->lock, flags);
436 }
437 
438 static irqreturn_t wcn36xx_irq_tx_complete(int irq, void *dev)
439 {
440 	struct wcn36xx *wcn = (struct wcn36xx *)dev;
441 	int int_src, int_reason;
442 
443 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_INT_SRC_RAW_REG, &int_src);
444 
445 	if (int_src & WCN36XX_INT_MASK_CHAN_TX_H) {
446 		wcn36xx_dxe_read_register(wcn,
447 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_TX_H,
448 					  &int_reason);
449 
450 		wcn36xx_dxe_write_register(wcn,
451 					   WCN36XX_DXE_0_INT_CLR,
452 					   WCN36XX_INT_MASK_CHAN_TX_H);
453 
454 		if (int_reason & WCN36XX_CH_STAT_INT_ERR_MASK ) {
455 			wcn36xx_dxe_write_register(wcn,
456 						   WCN36XX_DXE_0_INT_ERR_CLR,
457 						   WCN36XX_INT_MASK_CHAN_TX_H);
458 
459 			wcn36xx_err("DXE IRQ reported error: 0x%x in high TX channel\n",
460 					int_src);
461 		}
462 
463 		if (int_reason & WCN36XX_CH_STAT_INT_DONE_MASK) {
464 			wcn36xx_dxe_write_register(wcn,
465 						   WCN36XX_DXE_0_INT_DONE_CLR,
466 						   WCN36XX_INT_MASK_CHAN_TX_H);
467 		}
468 
469 		if (int_reason & WCN36XX_CH_STAT_INT_ED_MASK) {
470 			wcn36xx_dxe_write_register(wcn,
471 						   WCN36XX_DXE_0_INT_ED_CLR,
472 						   WCN36XX_INT_MASK_CHAN_TX_H);
473 		}
474 
475 		wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ready high, reason %08x\n",
476 			    int_reason);
477 
478 		if (int_reason & (WCN36XX_CH_STAT_INT_DONE_MASK |
479 				  WCN36XX_CH_STAT_INT_ED_MASK)) {
480 			reap_tx_dxes(wcn, &wcn->dxe_tx_h_ch);
481 		}
482 	}
483 
484 	if (int_src & WCN36XX_INT_MASK_CHAN_TX_L) {
485 		wcn36xx_dxe_read_register(wcn,
486 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_TX_L,
487 					  &int_reason);
488 
489 		wcn36xx_dxe_write_register(wcn,
490 					   WCN36XX_DXE_0_INT_CLR,
491 					   WCN36XX_INT_MASK_CHAN_TX_L);
492 
493 		if (int_reason & WCN36XX_CH_STAT_INT_ERR_MASK ) {
494 			wcn36xx_dxe_write_register(wcn,
495 						   WCN36XX_DXE_0_INT_ERR_CLR,
496 						   WCN36XX_INT_MASK_CHAN_TX_L);
497 
498 			wcn36xx_err("DXE IRQ reported error: 0x%x in low TX channel\n",
499 					int_src);
500 		}
501 
502 		if (int_reason & WCN36XX_CH_STAT_INT_DONE_MASK) {
503 			wcn36xx_dxe_write_register(wcn,
504 						   WCN36XX_DXE_0_INT_DONE_CLR,
505 						   WCN36XX_INT_MASK_CHAN_TX_L);
506 		}
507 
508 		if (int_reason & WCN36XX_CH_STAT_INT_ED_MASK) {
509 			wcn36xx_dxe_write_register(wcn,
510 						   WCN36XX_DXE_0_INT_ED_CLR,
511 						   WCN36XX_INT_MASK_CHAN_TX_L);
512 		}
513 
514 		wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ready low, reason %08x\n",
515 			    int_reason);
516 
517 		if (int_reason & (WCN36XX_CH_STAT_INT_DONE_MASK |
518 				  WCN36XX_CH_STAT_INT_ED_MASK)) {
519 			reap_tx_dxes(wcn, &wcn->dxe_tx_l_ch);
520 		}
521 	}
522 
523 	return IRQ_HANDLED;
524 }
525 
526 static irqreturn_t wcn36xx_irq_rx_ready(int irq, void *dev)
527 {
528 	struct wcn36xx *wcn = (struct wcn36xx *)dev;
529 
530 	wcn36xx_dxe_rx_frame(wcn);
531 
532 	return IRQ_HANDLED;
533 }
534 
535 static int wcn36xx_dxe_request_irqs(struct wcn36xx *wcn)
536 {
537 	int ret;
538 
539 	ret = request_irq(wcn->tx_irq, wcn36xx_irq_tx_complete,
540 			  IRQF_TRIGGER_HIGH, "wcn36xx_tx", wcn);
541 	if (ret) {
542 		wcn36xx_err("failed to alloc tx irq\n");
543 		goto out_err;
544 	}
545 
546 	ret = request_irq(wcn->rx_irq, wcn36xx_irq_rx_ready, IRQF_TRIGGER_HIGH,
547 			  "wcn36xx_rx", wcn);
548 	if (ret) {
549 		wcn36xx_err("failed to alloc rx irq\n");
550 		goto out_txirq;
551 	}
552 
553 	enable_irq_wake(wcn->rx_irq);
554 
555 	return 0;
556 
557 out_txirq:
558 	free_irq(wcn->tx_irq, wcn);
559 out_err:
560 	return ret;
561 
562 }
563 
564 static int wcn36xx_rx_handle_packets(struct wcn36xx *wcn,
565 				     struct wcn36xx_dxe_ch *ch,
566 				     u32 ctrl,
567 				     u32 en_mask,
568 				     u32 int_mask,
569 				     u32 status_reg)
570 {
571 	struct wcn36xx_dxe_desc *dxe;
572 	struct wcn36xx_dxe_ctl *ctl;
573 	dma_addr_t  dma_addr;
574 	struct sk_buff *skb;
575 	u32 int_reason;
576 	int ret;
577 
578 	wcn36xx_dxe_read_register(wcn, status_reg, &int_reason);
579 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_0_INT_CLR, int_mask);
580 
581 	if (int_reason & WCN36XX_CH_STAT_INT_ERR_MASK) {
582 		wcn36xx_dxe_write_register(wcn,
583 					   WCN36XX_DXE_0_INT_ERR_CLR,
584 					   int_mask);
585 
586 		wcn36xx_err("DXE IRQ reported error on RX channel\n");
587 	}
588 
589 	if (int_reason & WCN36XX_CH_STAT_INT_DONE_MASK)
590 		wcn36xx_dxe_write_register(wcn,
591 					   WCN36XX_DXE_0_INT_DONE_CLR,
592 					   int_mask);
593 
594 	if (int_reason & WCN36XX_CH_STAT_INT_ED_MASK)
595 		wcn36xx_dxe_write_register(wcn,
596 					   WCN36XX_DXE_0_INT_ED_CLR,
597 					   int_mask);
598 
599 	if (!(int_reason & (WCN36XX_CH_STAT_INT_DONE_MASK |
600 			    WCN36XX_CH_STAT_INT_ED_MASK)))
601 		return 0;
602 
603 	spin_lock(&ch->lock);
604 
605 	ctl = ch->head_blk_ctl;
606 	dxe = ctl->desc;
607 
608 	while (!(READ_ONCE(dxe->ctrl) & WCN36xx_DXE_CTRL_VLD)) {
609 		/* do not read until we own DMA descriptor */
610 		dma_rmb();
611 
612 		/* read/modify DMA descriptor */
613 		skb = ctl->skb;
614 		dma_addr = dxe->dst_addr_l;
615 		ret = wcn36xx_dxe_fill_skb(wcn->dev, ctl, GFP_ATOMIC);
616 		if (0 == ret) {
617 			/* new skb allocation ok. Use the new one and queue
618 			 * the old one to network system.
619 			 */
620 			dma_unmap_single(wcn->dev, dma_addr, WCN36XX_PKT_SIZE,
621 					DMA_FROM_DEVICE);
622 			wcn36xx_rx_skb(wcn, skb);
623 		}
624 		/* else keep old skb not submitted and reuse it for rx DMA
625 		 * (dropping the packet that it contained)
626 		 */
627 
628 		/* flush descriptor changes before re-marking as valid */
629 		dma_wmb();
630 		dxe->ctrl = ctrl;
631 
632 		ctl = ctl->next;
633 		dxe = ctl->desc;
634 	}
635 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_ENCH_ADDR, en_mask);
636 
637 	ch->head_blk_ctl = ctl;
638 
639 	spin_unlock(&ch->lock);
640 
641 	return 0;
642 }
643 
644 void wcn36xx_dxe_rx_frame(struct wcn36xx *wcn)
645 {
646 	int int_src;
647 
648 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_INT_SRC_RAW_REG, &int_src);
649 
650 	/* RX_LOW_PRI */
651 	if (int_src & WCN36XX_DXE_INT_CH1_MASK)
652 		wcn36xx_rx_handle_packets(wcn, &wcn->dxe_rx_l_ch,
653 					  WCN36XX_DXE_CTRL_RX_L,
654 					  WCN36XX_DXE_INT_CH1_MASK,
655 					  WCN36XX_INT_MASK_CHAN_RX_L,
656 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_RX_L);
657 
658 	/* RX_HIGH_PRI */
659 	if (int_src & WCN36XX_DXE_INT_CH3_MASK)
660 		wcn36xx_rx_handle_packets(wcn, &wcn->dxe_rx_h_ch,
661 					  WCN36XX_DXE_CTRL_RX_H,
662 					  WCN36XX_DXE_INT_CH3_MASK,
663 					  WCN36XX_INT_MASK_CHAN_RX_H,
664 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_RX_H);
665 
666 	if (!int_src)
667 		wcn36xx_warn("No DXE interrupt pending\n");
668 }
669 
670 int wcn36xx_dxe_allocate_mem_pools(struct wcn36xx *wcn)
671 {
672 	size_t s;
673 	void *cpu_addr;
674 
675 	/* Allocate BD headers for MGMT frames */
676 
677 	/* Where this come from ask QC */
678 	wcn->mgmt_mem_pool.chunk_size =	WCN36XX_BD_CHUNK_SIZE +
679 		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
680 
681 	s = wcn->mgmt_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_H;
682 	cpu_addr = dma_alloc_coherent(wcn->dev, s,
683 				      &wcn->mgmt_mem_pool.phy_addr,
684 				      GFP_KERNEL);
685 	if (!cpu_addr)
686 		goto out_err;
687 
688 	wcn->mgmt_mem_pool.virt_addr = cpu_addr;
689 
690 	/* Allocate BD headers for DATA frames */
691 
692 	/* Where this come from ask QC */
693 	wcn->data_mem_pool.chunk_size = WCN36XX_BD_CHUNK_SIZE +
694 		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
695 
696 	s = wcn->data_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_L;
697 	cpu_addr = dma_alloc_coherent(wcn->dev, s,
698 				      &wcn->data_mem_pool.phy_addr,
699 				      GFP_KERNEL);
700 	if (!cpu_addr)
701 		goto out_err;
702 
703 	wcn->data_mem_pool.virt_addr = cpu_addr;
704 
705 	return 0;
706 
707 out_err:
708 	wcn36xx_dxe_free_mem_pools(wcn);
709 	wcn36xx_err("Failed to allocate BD mempool\n");
710 	return -ENOMEM;
711 }
712 
713 void wcn36xx_dxe_free_mem_pools(struct wcn36xx *wcn)
714 {
715 	if (wcn->mgmt_mem_pool.virt_addr)
716 		dma_free_coherent(wcn->dev, wcn->mgmt_mem_pool.chunk_size *
717 				  WCN36XX_DXE_CH_DESC_NUMB_TX_H,
718 				  wcn->mgmt_mem_pool.virt_addr,
719 				  wcn->mgmt_mem_pool.phy_addr);
720 
721 	if (wcn->data_mem_pool.virt_addr) {
722 		dma_free_coherent(wcn->dev, wcn->data_mem_pool.chunk_size *
723 				  WCN36XX_DXE_CH_DESC_NUMB_TX_L,
724 				  wcn->data_mem_pool.virt_addr,
725 				  wcn->data_mem_pool.phy_addr);
726 	}
727 }
728 
729 int wcn36xx_dxe_tx_frame(struct wcn36xx *wcn,
730 			 struct wcn36xx_vif *vif_priv,
731 			 struct wcn36xx_tx_bd *bd,
732 			 struct sk_buff *skb,
733 			 bool is_low)
734 {
735 	struct wcn36xx_dxe_desc *desc_bd, *desc_skb;
736 	struct wcn36xx_dxe_ctl *ctl_bd, *ctl_skb;
737 	struct wcn36xx_dxe_ch *ch = NULL;
738 	unsigned long flags;
739 	int ret;
740 
741 	ch = is_low ? &wcn->dxe_tx_l_ch : &wcn->dxe_tx_h_ch;
742 
743 	spin_lock_irqsave(&ch->lock, flags);
744 	ctl_bd = ch->head_blk_ctl;
745 	ctl_skb = ctl_bd->next;
746 
747 	/*
748 	 * If skb is not null that means that we reached the tail of the ring
749 	 * hence ring is full. Stop queues to let mac80211 back off until ring
750 	 * has an empty slot again.
751 	 */
752 	if (NULL != ctl_skb->skb) {
753 		ieee80211_stop_queues(wcn->hw);
754 		wcn->queues_stopped = true;
755 		spin_unlock_irqrestore(&ch->lock, flags);
756 		return -EBUSY;
757 	}
758 
759 	if (unlikely(ctl_skb->bd_cpu_addr)) {
760 		wcn36xx_err("bd_cpu_addr cannot be NULL for skb DXE\n");
761 		ret = -EINVAL;
762 		goto unlock;
763 	}
764 
765 	desc_bd = ctl_bd->desc;
766 	desc_skb = ctl_skb->desc;
767 
768 	ctl_bd->skb = NULL;
769 
770 	/* write buffer descriptor */
771 	memcpy(ctl_bd->bd_cpu_addr, bd, sizeof(*bd));
772 
773 	/* Set source address of the BD we send */
774 	desc_bd->src_addr_l = ctl_bd->bd_phy_addr;
775 	desc_bd->dst_addr_l = ch->dxe_wq;
776 	desc_bd->fr_len = sizeof(struct wcn36xx_tx_bd);
777 
778 	wcn36xx_dbg(WCN36XX_DBG_DXE, "DXE TX\n");
779 
780 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "DESC1 >>> ",
781 			 (char *)desc_bd, sizeof(*desc_bd));
782 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP,
783 			 "BD   >>> ", (char *)ctl_bd->bd_cpu_addr,
784 			 sizeof(struct wcn36xx_tx_bd));
785 
786 	desc_skb->src_addr_l = dma_map_single(wcn->dev,
787 					      skb->data,
788 					      skb->len,
789 					      DMA_TO_DEVICE);
790 	if (dma_mapping_error(wcn->dev, desc_skb->src_addr_l)) {
791 		dev_err(wcn->dev, "unable to DMA map src_addr_l\n");
792 		ret = -ENOMEM;
793 		goto unlock;
794 	}
795 
796 	ctl_skb->skb = skb;
797 	desc_skb->dst_addr_l = ch->dxe_wq;
798 	desc_skb->fr_len = ctl_skb->skb->len;
799 
800 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "DESC2 >>> ",
801 			 (char *)desc_skb, sizeof(*desc_skb));
802 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "SKB   >>> ",
803 			 (char *)ctl_skb->skb->data, ctl_skb->skb->len);
804 
805 	/* Move the head of the ring to the next empty descriptor */
806 	ch->head_blk_ctl = ctl_skb->next;
807 
808 	/* Commit all previous writes and set descriptors to VALID */
809 	wmb();
810 	desc_skb->ctrl = ch->ctrl_skb;
811 	wmb();
812 	desc_bd->ctrl = ch->ctrl_bd;
813 
814 	/*
815 	 * When connected and trying to send data frame chip can be in sleep
816 	 * mode and writing to the register will not wake up the chip. Instead
817 	 * notify chip about new frame through SMSM bus.
818 	 */
819 	if (is_low &&  vif_priv->pw_state == WCN36XX_BMPS) {
820 		qcom_smem_state_update_bits(wcn->tx_rings_empty_state,
821 					    WCN36XX_SMSM_WLAN_TX_ENABLE,
822 					    WCN36XX_SMSM_WLAN_TX_ENABLE);
823 	} else {
824 		/* indicate End Of Packet and generate interrupt on descriptor
825 		 * done.
826 		 */
827 		wcn36xx_dxe_write_register(wcn,
828 			ch->reg_ctrl, ch->def_ctrl);
829 	}
830 
831 	ret = 0;
832 unlock:
833 	spin_unlock_irqrestore(&ch->lock, flags);
834 	return ret;
835 }
836 
837 int wcn36xx_dxe_init(struct wcn36xx *wcn)
838 {
839 	int reg_data = 0, ret;
840 
841 	reg_data = WCN36XX_DXE_REG_RESET;
842 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_REG_CSR_RESET, reg_data);
843 
844 	/* Select channels for rx avail and xfer done interrupts... */
845 	reg_data = (WCN36XX_DXE_INT_CH3_MASK | WCN36XX_DXE_INT_CH1_MASK) << 16 |
846 		    WCN36XX_DXE_INT_CH0_MASK | WCN36XX_DXE_INT_CH4_MASK;
847 	if (wcn->is_pronto)
848 		wcn36xx_ccu_write_register(wcn, WCN36XX_CCU_DXE_INT_SELECT_PRONTO, reg_data);
849 	else
850 		wcn36xx_ccu_write_register(wcn, WCN36XX_CCU_DXE_INT_SELECT_RIVA, reg_data);
851 
852 	/***************************************/
853 	/* Init descriptors for TX LOW channel */
854 	/***************************************/
855 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_tx_l_ch);
856 	if (ret) {
857 		dev_err(wcn->dev, "Error allocating descriptor\n");
858 		return ret;
859 	}
860 	wcn36xx_dxe_init_tx_bd(&wcn->dxe_tx_l_ch, &wcn->data_mem_pool);
861 
862 	/* Write channel head to a NEXT register */
863 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_TX_L,
864 		wcn->dxe_tx_l_ch.head_blk_ctl->desc_phy_addr);
865 
866 	/* Program DMA destination addr for TX LOW */
867 	wcn36xx_dxe_write_register(wcn,
868 		WCN36XX_DXE_CH_DEST_ADDR_TX_L,
869 		WCN36XX_DXE_WQ_TX_L);
870 
871 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_REG_CH_EN, &reg_data);
872 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_TX_L);
873 
874 	/***************************************/
875 	/* Init descriptors for TX HIGH channel */
876 	/***************************************/
877 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_tx_h_ch);
878 	if (ret) {
879 		dev_err(wcn->dev, "Error allocating descriptor\n");
880 		goto out_err_txh_ch;
881 	}
882 
883 	wcn36xx_dxe_init_tx_bd(&wcn->dxe_tx_h_ch, &wcn->mgmt_mem_pool);
884 
885 	/* Write channel head to a NEXT register */
886 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_TX_H,
887 		wcn->dxe_tx_h_ch.head_blk_ctl->desc_phy_addr);
888 
889 	/* Program DMA destination addr for TX HIGH */
890 	wcn36xx_dxe_write_register(wcn,
891 		WCN36XX_DXE_CH_DEST_ADDR_TX_H,
892 		WCN36XX_DXE_WQ_TX_H);
893 
894 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_REG_CH_EN, &reg_data);
895 
896 	/* Enable channel interrupts */
897 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_TX_H);
898 
899 	/***************************************/
900 	/* Init descriptors for RX LOW channel */
901 	/***************************************/
902 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_rx_l_ch);
903 	if (ret) {
904 		dev_err(wcn->dev, "Error allocating descriptor\n");
905 		goto out_err_rxl_ch;
906 	}
907 
908 
909 	/* For RX we need to preallocated buffers */
910 	wcn36xx_dxe_ch_alloc_skb(wcn, &wcn->dxe_rx_l_ch);
911 
912 	/* Write channel head to a NEXT register */
913 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_RX_L,
914 		wcn->dxe_rx_l_ch.head_blk_ctl->desc_phy_addr);
915 
916 	/* Write DMA source address */
917 	wcn36xx_dxe_write_register(wcn,
918 		WCN36XX_DXE_CH_SRC_ADDR_RX_L,
919 		WCN36XX_DXE_WQ_RX_L);
920 
921 	/* Program preallocated destination address */
922 	wcn36xx_dxe_write_register(wcn,
923 		WCN36XX_DXE_CH_DEST_ADDR_RX_L,
924 		wcn->dxe_rx_l_ch.head_blk_ctl->desc->phy_next_l);
925 
926 	/* Enable default control registers */
927 	wcn36xx_dxe_write_register(wcn,
928 		WCN36XX_DXE_REG_CTL_RX_L,
929 		WCN36XX_DXE_CH_DEFAULT_CTL_RX_L);
930 
931 	/* Enable channel interrupts */
932 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_L);
933 
934 	/***************************************/
935 	/* Init descriptors for RX HIGH channel */
936 	/***************************************/
937 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_rx_h_ch);
938 	if (ret) {
939 		dev_err(wcn->dev, "Error allocating descriptor\n");
940 		goto out_err_rxh_ch;
941 	}
942 
943 	/* For RX we need to prealocat buffers */
944 	wcn36xx_dxe_ch_alloc_skb(wcn, &wcn->dxe_rx_h_ch);
945 
946 	/* Write chanel head to a NEXT register */
947 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_RX_H,
948 		wcn->dxe_rx_h_ch.head_blk_ctl->desc_phy_addr);
949 
950 	/* Write DMA source address */
951 	wcn36xx_dxe_write_register(wcn,
952 		WCN36XX_DXE_CH_SRC_ADDR_RX_H,
953 		WCN36XX_DXE_WQ_RX_H);
954 
955 	/* Program preallocated destination address */
956 	wcn36xx_dxe_write_register(wcn,
957 		WCN36XX_DXE_CH_DEST_ADDR_RX_H,
958 		 wcn->dxe_rx_h_ch.head_blk_ctl->desc->phy_next_l);
959 
960 	/* Enable default control registers */
961 	wcn36xx_dxe_write_register(wcn,
962 		WCN36XX_DXE_REG_CTL_RX_H,
963 		WCN36XX_DXE_CH_DEFAULT_CTL_RX_H);
964 
965 	/* Enable channel interrupts */
966 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_H);
967 
968 	ret = wcn36xx_dxe_request_irqs(wcn);
969 	if (ret < 0)
970 		goto out_err_irq;
971 
972 	timer_setup(&wcn->tx_ack_timer, wcn36xx_dxe_tx_timer, 0);
973 
974 	return 0;
975 
976 out_err_irq:
977 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_rx_h_ch);
978 out_err_rxh_ch:
979 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_rx_l_ch);
980 out_err_rxl_ch:
981 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_tx_h_ch);
982 out_err_txh_ch:
983 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_tx_l_ch);
984 
985 	return ret;
986 }
987 
988 void wcn36xx_dxe_deinit(struct wcn36xx *wcn)
989 {
990 	free_irq(wcn->tx_irq, wcn);
991 	free_irq(wcn->rx_irq, wcn);
992 	del_timer(&wcn->tx_ack_timer);
993 
994 	if (wcn->tx_ack_skb) {
995 		ieee80211_tx_status_irqsafe(wcn->hw, wcn->tx_ack_skb);
996 		wcn->tx_ack_skb = NULL;
997 	}
998 
999 	wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_l_ch);
1000 	wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_h_ch);
1001 }
1002