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 				/* Keep frame until TX status comes */
408 				ieee80211_free_txskb(wcn->hw, ctl->skb);
409 			}
410 
411 			if (wcn->queues_stopped) {
412 				wcn->queues_stopped = false;
413 				ieee80211_wake_queues(wcn->hw);
414 			}
415 
416 			ctl->skb = NULL;
417 		}
418 		ctl = ctl->next;
419 	} while (ctl != ch->head_blk_ctl);
420 
421 	ch->tail_blk_ctl = ctl;
422 	spin_unlock_irqrestore(&ch->lock, flags);
423 }
424 
425 static irqreturn_t wcn36xx_irq_tx_complete(int irq, void *dev)
426 {
427 	struct wcn36xx *wcn = (struct wcn36xx *)dev;
428 	int int_src, int_reason;
429 	bool transmitted = false;
430 
431 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_INT_SRC_RAW_REG, &int_src);
432 
433 	if (int_src & WCN36XX_INT_MASK_CHAN_TX_H) {
434 		wcn36xx_dxe_read_register(wcn,
435 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_TX_H,
436 					  &int_reason);
437 
438 		wcn36xx_dxe_write_register(wcn,
439 					   WCN36XX_DXE_0_INT_CLR,
440 					   WCN36XX_INT_MASK_CHAN_TX_H);
441 
442 		if (int_reason & WCN36XX_CH_STAT_INT_ERR_MASK ) {
443 			wcn36xx_dxe_write_register(wcn,
444 						   WCN36XX_DXE_0_INT_ERR_CLR,
445 						   WCN36XX_INT_MASK_CHAN_TX_H);
446 
447 			wcn36xx_err("DXE IRQ reported error: 0x%x in high TX channel\n",
448 					int_src);
449 		}
450 
451 		if (int_reason & WCN36XX_CH_STAT_INT_DONE_MASK) {
452 			wcn36xx_dxe_write_register(wcn,
453 						   WCN36XX_DXE_0_INT_DONE_CLR,
454 						   WCN36XX_INT_MASK_CHAN_TX_H);
455 		}
456 
457 		if (int_reason & WCN36XX_CH_STAT_INT_ED_MASK) {
458 			wcn36xx_dxe_write_register(wcn,
459 						   WCN36XX_DXE_0_INT_ED_CLR,
460 						   WCN36XX_INT_MASK_CHAN_TX_H);
461 		}
462 
463 		wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ready high, reason %08x\n",
464 			    int_reason);
465 
466 		if (int_reason & (WCN36XX_CH_STAT_INT_DONE_MASK |
467 				  WCN36XX_CH_STAT_INT_ED_MASK)) {
468 			reap_tx_dxes(wcn, &wcn->dxe_tx_h_ch);
469 			transmitted = true;
470 		}
471 	}
472 
473 	if (int_src & WCN36XX_INT_MASK_CHAN_TX_L) {
474 		wcn36xx_dxe_read_register(wcn,
475 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_TX_L,
476 					  &int_reason);
477 
478 		wcn36xx_dxe_write_register(wcn,
479 					   WCN36XX_DXE_0_INT_CLR,
480 					   WCN36XX_INT_MASK_CHAN_TX_L);
481 
482 
483 		if (int_reason & WCN36XX_CH_STAT_INT_ERR_MASK ) {
484 			wcn36xx_dxe_write_register(wcn,
485 						   WCN36XX_DXE_0_INT_ERR_CLR,
486 						   WCN36XX_INT_MASK_CHAN_TX_L);
487 
488 			wcn36xx_err("DXE IRQ reported error: 0x%x in low TX channel\n",
489 					int_src);
490 		}
491 
492 		if (int_reason & WCN36XX_CH_STAT_INT_DONE_MASK) {
493 			wcn36xx_dxe_write_register(wcn,
494 						   WCN36XX_DXE_0_INT_DONE_CLR,
495 						   WCN36XX_INT_MASK_CHAN_TX_L);
496 		}
497 
498 		if (int_reason & WCN36XX_CH_STAT_INT_ED_MASK) {
499 			wcn36xx_dxe_write_register(wcn,
500 						   WCN36XX_DXE_0_INT_ED_CLR,
501 						   WCN36XX_INT_MASK_CHAN_TX_L);
502 		}
503 
504 		wcn36xx_dbg(WCN36XX_DBG_DXE, "dxe tx ready low, reason %08x\n",
505 			    int_reason);
506 
507 		if (int_reason & (WCN36XX_CH_STAT_INT_DONE_MASK |
508 				  WCN36XX_CH_STAT_INT_ED_MASK)) {
509 			reap_tx_dxes(wcn, &wcn->dxe_tx_l_ch);
510 			transmitted = true;
511 		}
512 	}
513 
514 	spin_lock(&wcn->dxe_lock);
515 	if (wcn->tx_ack_skb && transmitted) {
516 		struct ieee80211_tx_info *info = IEEE80211_SKB_CB(wcn->tx_ack_skb);
517 
518 		/* TX complete, no need to wait for 802.11 ack indication */
519 		if (info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS &&
520 		    info->flags & IEEE80211_TX_CTL_NO_ACK) {
521 			info->flags |= IEEE80211_TX_STAT_NOACK_TRANSMITTED;
522 			del_timer(&wcn->tx_ack_timer);
523 			ieee80211_tx_status_irqsafe(wcn->hw, wcn->tx_ack_skb);
524 			wcn->tx_ack_skb = NULL;
525 			ieee80211_wake_queues(wcn->hw);
526 		}
527 	}
528 	spin_unlock(&wcn->dxe_lock);
529 
530 	return IRQ_HANDLED;
531 }
532 
533 static irqreturn_t wcn36xx_irq_rx_ready(int irq, void *dev)
534 {
535 	struct wcn36xx *wcn = (struct wcn36xx *)dev;
536 
537 	wcn36xx_dxe_rx_frame(wcn);
538 
539 	return IRQ_HANDLED;
540 }
541 
542 static int wcn36xx_dxe_request_irqs(struct wcn36xx *wcn)
543 {
544 	int ret;
545 
546 	ret = request_irq(wcn->tx_irq, wcn36xx_irq_tx_complete,
547 			  IRQF_TRIGGER_HIGH, "wcn36xx_tx", wcn);
548 	if (ret) {
549 		wcn36xx_err("failed to alloc tx irq\n");
550 		goto out_err;
551 	}
552 
553 	ret = request_irq(wcn->rx_irq, wcn36xx_irq_rx_ready, IRQF_TRIGGER_HIGH,
554 			  "wcn36xx_rx", wcn);
555 	if (ret) {
556 		wcn36xx_err("failed to alloc rx irq\n");
557 		goto out_txirq;
558 	}
559 
560 	enable_irq_wake(wcn->rx_irq);
561 
562 	return 0;
563 
564 out_txirq:
565 	free_irq(wcn->tx_irq, wcn);
566 out_err:
567 	return ret;
568 
569 }
570 
571 static int wcn36xx_rx_handle_packets(struct wcn36xx *wcn,
572 				     struct wcn36xx_dxe_ch *ch,
573 				     u32 ctrl,
574 				     u32 en_mask,
575 				     u32 int_mask,
576 				     u32 status_reg)
577 {
578 	struct wcn36xx_dxe_desc *dxe;
579 	struct wcn36xx_dxe_ctl *ctl;
580 	dma_addr_t  dma_addr;
581 	struct sk_buff *skb;
582 	u32 int_reason;
583 	int ret;
584 
585 	wcn36xx_dxe_read_register(wcn, status_reg, &int_reason);
586 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_0_INT_CLR, int_mask);
587 
588 	if (int_reason & WCN36XX_CH_STAT_INT_ERR_MASK) {
589 		wcn36xx_dxe_write_register(wcn,
590 					   WCN36XX_DXE_0_INT_ERR_CLR,
591 					   int_mask);
592 
593 		wcn36xx_err("DXE IRQ reported error on RX channel\n");
594 	}
595 
596 	if (int_reason & WCN36XX_CH_STAT_INT_DONE_MASK)
597 		wcn36xx_dxe_write_register(wcn,
598 					   WCN36XX_DXE_0_INT_DONE_CLR,
599 					   int_mask);
600 
601 	if (int_reason & WCN36XX_CH_STAT_INT_ED_MASK)
602 		wcn36xx_dxe_write_register(wcn,
603 					   WCN36XX_DXE_0_INT_ED_CLR,
604 					   int_mask);
605 
606 	if (!(int_reason & (WCN36XX_CH_STAT_INT_DONE_MASK |
607 			    WCN36XX_CH_STAT_INT_ED_MASK)))
608 		return 0;
609 
610 	spin_lock(&ch->lock);
611 
612 	ctl = ch->head_blk_ctl;
613 	dxe = ctl->desc;
614 
615 	while (!(READ_ONCE(dxe->ctrl) & WCN36xx_DXE_CTRL_VLD)) {
616 		skb = ctl->skb;
617 		dma_addr = dxe->dst_addr_l;
618 		ret = wcn36xx_dxe_fill_skb(wcn->dev, ctl, GFP_ATOMIC);
619 		if (0 == ret) {
620 			/* new skb allocation ok. Use the new one and queue
621 			 * the old one to network system.
622 			 */
623 			dma_unmap_single(wcn->dev, dma_addr, WCN36XX_PKT_SIZE,
624 					DMA_FROM_DEVICE);
625 			wcn36xx_rx_skb(wcn, skb);
626 		} /* else keep old skb not submitted and use it for rx DMA */
627 
628 		dxe->ctrl = ctrl;
629 		ctl = ctl->next;
630 		dxe = ctl->desc;
631 	}
632 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_ENCH_ADDR, en_mask);
633 
634 	ch->head_blk_ctl = ctl;
635 
636 	spin_unlock(&ch->lock);
637 
638 	return 0;
639 }
640 
641 void wcn36xx_dxe_rx_frame(struct wcn36xx *wcn)
642 {
643 	int int_src;
644 
645 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_INT_SRC_RAW_REG, &int_src);
646 
647 	/* RX_LOW_PRI */
648 	if (int_src & WCN36XX_DXE_INT_CH1_MASK)
649 		wcn36xx_rx_handle_packets(wcn, &wcn->dxe_rx_l_ch,
650 					  WCN36XX_DXE_CTRL_RX_L,
651 					  WCN36XX_DXE_INT_CH1_MASK,
652 					  WCN36XX_INT_MASK_CHAN_RX_L,
653 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_RX_L);
654 
655 	/* RX_HIGH_PRI */
656 	if (int_src & WCN36XX_DXE_INT_CH3_MASK)
657 		wcn36xx_rx_handle_packets(wcn, &wcn->dxe_rx_h_ch,
658 					  WCN36XX_DXE_CTRL_RX_H,
659 					  WCN36XX_DXE_INT_CH3_MASK,
660 					  WCN36XX_INT_MASK_CHAN_RX_H,
661 					  WCN36XX_DXE_CH_STATUS_REG_ADDR_RX_H);
662 
663 	if (!int_src)
664 		wcn36xx_warn("No DXE interrupt pending\n");
665 }
666 
667 int wcn36xx_dxe_allocate_mem_pools(struct wcn36xx *wcn)
668 {
669 	size_t s;
670 	void *cpu_addr;
671 
672 	/* Allocate BD headers for MGMT frames */
673 
674 	/* Where this come from ask QC */
675 	wcn->mgmt_mem_pool.chunk_size =	WCN36XX_BD_CHUNK_SIZE +
676 		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
677 
678 	s = wcn->mgmt_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_H;
679 	cpu_addr = dma_alloc_coherent(wcn->dev, s,
680 				      &wcn->mgmt_mem_pool.phy_addr,
681 				      GFP_KERNEL);
682 	if (!cpu_addr)
683 		goto out_err;
684 
685 	wcn->mgmt_mem_pool.virt_addr = cpu_addr;
686 
687 	/* Allocate BD headers for DATA frames */
688 
689 	/* Where this come from ask QC */
690 	wcn->data_mem_pool.chunk_size = WCN36XX_BD_CHUNK_SIZE +
691 		16 - (WCN36XX_BD_CHUNK_SIZE % 8);
692 
693 	s = wcn->data_mem_pool.chunk_size * WCN36XX_DXE_CH_DESC_NUMB_TX_L;
694 	cpu_addr = dma_alloc_coherent(wcn->dev, s,
695 				      &wcn->data_mem_pool.phy_addr,
696 				      GFP_KERNEL);
697 	if (!cpu_addr)
698 		goto out_err;
699 
700 	wcn->data_mem_pool.virt_addr = cpu_addr;
701 
702 	return 0;
703 
704 out_err:
705 	wcn36xx_dxe_free_mem_pools(wcn);
706 	wcn36xx_err("Failed to allocate BD mempool\n");
707 	return -ENOMEM;
708 }
709 
710 void wcn36xx_dxe_free_mem_pools(struct wcn36xx *wcn)
711 {
712 	if (wcn->mgmt_mem_pool.virt_addr)
713 		dma_free_coherent(wcn->dev, wcn->mgmt_mem_pool.chunk_size *
714 				  WCN36XX_DXE_CH_DESC_NUMB_TX_H,
715 				  wcn->mgmt_mem_pool.virt_addr,
716 				  wcn->mgmt_mem_pool.phy_addr);
717 
718 	if (wcn->data_mem_pool.virt_addr) {
719 		dma_free_coherent(wcn->dev, wcn->data_mem_pool.chunk_size *
720 				  WCN36XX_DXE_CH_DESC_NUMB_TX_L,
721 				  wcn->data_mem_pool.virt_addr,
722 				  wcn->data_mem_pool.phy_addr);
723 	}
724 }
725 
726 int wcn36xx_dxe_tx_frame(struct wcn36xx *wcn,
727 			 struct wcn36xx_vif *vif_priv,
728 			 struct wcn36xx_tx_bd *bd,
729 			 struct sk_buff *skb,
730 			 bool is_low)
731 {
732 	struct wcn36xx_dxe_desc *desc_bd, *desc_skb;
733 	struct wcn36xx_dxe_ctl *ctl_bd, *ctl_skb;
734 	struct wcn36xx_dxe_ch *ch = NULL;
735 	unsigned long flags;
736 	int ret;
737 
738 	ch = is_low ? &wcn->dxe_tx_l_ch : &wcn->dxe_tx_h_ch;
739 
740 	spin_lock_irqsave(&ch->lock, flags);
741 	ctl_bd = ch->head_blk_ctl;
742 	ctl_skb = ctl_bd->next;
743 
744 	/*
745 	 * If skb is not null that means that we reached the tail of the ring
746 	 * hence ring is full. Stop queues to let mac80211 back off until ring
747 	 * has an empty slot again.
748 	 */
749 	if (NULL != ctl_skb->skb) {
750 		ieee80211_stop_queues(wcn->hw);
751 		wcn->queues_stopped = true;
752 		spin_unlock_irqrestore(&ch->lock, flags);
753 		return -EBUSY;
754 	}
755 
756 	if (unlikely(ctl_skb->bd_cpu_addr)) {
757 		wcn36xx_err("bd_cpu_addr cannot be NULL for skb DXE\n");
758 		ret = -EINVAL;
759 		goto unlock;
760 	}
761 
762 	desc_bd = ctl_bd->desc;
763 	desc_skb = ctl_skb->desc;
764 
765 	ctl_bd->skb = NULL;
766 
767 	/* write buffer descriptor */
768 	memcpy(ctl_bd->bd_cpu_addr, bd, sizeof(*bd));
769 
770 	/* Set source address of the BD we send */
771 	desc_bd->src_addr_l = ctl_bd->bd_phy_addr;
772 	desc_bd->dst_addr_l = ch->dxe_wq;
773 	desc_bd->fr_len = sizeof(struct wcn36xx_tx_bd);
774 
775 	wcn36xx_dbg(WCN36XX_DBG_DXE, "DXE TX\n");
776 
777 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "DESC1 >>> ",
778 			 (char *)desc_bd, sizeof(*desc_bd));
779 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP,
780 			 "BD   >>> ", (char *)ctl_bd->bd_cpu_addr,
781 			 sizeof(struct wcn36xx_tx_bd));
782 
783 	desc_skb->src_addr_l = dma_map_single(wcn->dev,
784 					      skb->data,
785 					      skb->len,
786 					      DMA_TO_DEVICE);
787 	if (dma_mapping_error(wcn->dev, desc_skb->src_addr_l)) {
788 		dev_err(wcn->dev, "unable to DMA map src_addr_l\n");
789 		ret = -ENOMEM;
790 		goto unlock;
791 	}
792 
793 	ctl_skb->skb = skb;
794 	desc_skb->dst_addr_l = ch->dxe_wq;
795 	desc_skb->fr_len = ctl_skb->skb->len;
796 
797 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "DESC2 >>> ",
798 			 (char *)desc_skb, sizeof(*desc_skb));
799 	wcn36xx_dbg_dump(WCN36XX_DBG_DXE_DUMP, "SKB   >>> ",
800 			 (char *)ctl_skb->skb->data, ctl_skb->skb->len);
801 
802 	/* Move the head of the ring to the next empty descriptor */
803 	ch->head_blk_ctl = ctl_skb->next;
804 
805 	/* Commit all previous writes and set descriptors to VALID */
806 	wmb();
807 	desc_skb->ctrl = ch->ctrl_skb;
808 	wmb();
809 	desc_bd->ctrl = ch->ctrl_bd;
810 
811 	/*
812 	 * When connected and trying to send data frame chip can be in sleep
813 	 * mode and writing to the register will not wake up the chip. Instead
814 	 * notify chip about new frame through SMSM bus.
815 	 */
816 	if (is_low &&  vif_priv->pw_state == WCN36XX_BMPS) {
817 		qcom_smem_state_update_bits(wcn->tx_rings_empty_state,
818 					    WCN36XX_SMSM_WLAN_TX_ENABLE,
819 					    WCN36XX_SMSM_WLAN_TX_ENABLE);
820 	} else {
821 		/* indicate End Of Packet and generate interrupt on descriptor
822 		 * done.
823 		 */
824 		wcn36xx_dxe_write_register(wcn,
825 			ch->reg_ctrl, ch->def_ctrl);
826 	}
827 
828 	ret = 0;
829 unlock:
830 	spin_unlock_irqrestore(&ch->lock, flags);
831 	return ret;
832 }
833 
834 int wcn36xx_dxe_init(struct wcn36xx *wcn)
835 {
836 	int reg_data = 0, ret;
837 
838 	reg_data = WCN36XX_DXE_REG_RESET;
839 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_REG_CSR_RESET, reg_data);
840 
841 	/* Select channels for rx avail and xfer done interrupts... */
842 	reg_data = (WCN36XX_DXE_INT_CH3_MASK | WCN36XX_DXE_INT_CH1_MASK) << 16 |
843 		    WCN36XX_DXE_INT_CH0_MASK | WCN36XX_DXE_INT_CH4_MASK;
844 	if (wcn->is_pronto)
845 		wcn36xx_ccu_write_register(wcn, WCN36XX_CCU_DXE_INT_SELECT_PRONTO, reg_data);
846 	else
847 		wcn36xx_ccu_write_register(wcn, WCN36XX_CCU_DXE_INT_SELECT_RIVA, reg_data);
848 
849 	/***************************************/
850 	/* Init descriptors for TX LOW channel */
851 	/***************************************/
852 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_tx_l_ch);
853 	if (ret) {
854 		dev_err(wcn->dev, "Error allocating descriptor\n");
855 		return ret;
856 	}
857 	wcn36xx_dxe_init_tx_bd(&wcn->dxe_tx_l_ch, &wcn->data_mem_pool);
858 
859 	/* Write channel head to a NEXT register */
860 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_TX_L,
861 		wcn->dxe_tx_l_ch.head_blk_ctl->desc_phy_addr);
862 
863 	/* Program DMA destination addr for TX LOW */
864 	wcn36xx_dxe_write_register(wcn,
865 		WCN36XX_DXE_CH_DEST_ADDR_TX_L,
866 		WCN36XX_DXE_WQ_TX_L);
867 
868 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_REG_CH_EN, &reg_data);
869 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_TX_L);
870 
871 	/***************************************/
872 	/* Init descriptors for TX HIGH channel */
873 	/***************************************/
874 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_tx_h_ch);
875 	if (ret) {
876 		dev_err(wcn->dev, "Error allocating descriptor\n");
877 		goto out_err_txh_ch;
878 	}
879 
880 	wcn36xx_dxe_init_tx_bd(&wcn->dxe_tx_h_ch, &wcn->mgmt_mem_pool);
881 
882 	/* Write channel head to a NEXT register */
883 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_TX_H,
884 		wcn->dxe_tx_h_ch.head_blk_ctl->desc_phy_addr);
885 
886 	/* Program DMA destination addr for TX HIGH */
887 	wcn36xx_dxe_write_register(wcn,
888 		WCN36XX_DXE_CH_DEST_ADDR_TX_H,
889 		WCN36XX_DXE_WQ_TX_H);
890 
891 	wcn36xx_dxe_read_register(wcn, WCN36XX_DXE_REG_CH_EN, &reg_data);
892 
893 	/* Enable channel interrupts */
894 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_TX_H);
895 
896 	/***************************************/
897 	/* Init descriptors for RX LOW channel */
898 	/***************************************/
899 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_rx_l_ch);
900 	if (ret) {
901 		dev_err(wcn->dev, "Error allocating descriptor\n");
902 		goto out_err_rxl_ch;
903 	}
904 
905 
906 	/* For RX we need to preallocated buffers */
907 	wcn36xx_dxe_ch_alloc_skb(wcn, &wcn->dxe_rx_l_ch);
908 
909 	/* Write channel head to a NEXT register */
910 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_RX_L,
911 		wcn->dxe_rx_l_ch.head_blk_ctl->desc_phy_addr);
912 
913 	/* Write DMA source address */
914 	wcn36xx_dxe_write_register(wcn,
915 		WCN36XX_DXE_CH_SRC_ADDR_RX_L,
916 		WCN36XX_DXE_WQ_RX_L);
917 
918 	/* Program preallocated destination address */
919 	wcn36xx_dxe_write_register(wcn,
920 		WCN36XX_DXE_CH_DEST_ADDR_RX_L,
921 		wcn->dxe_rx_l_ch.head_blk_ctl->desc->phy_next_l);
922 
923 	/* Enable default control registers */
924 	wcn36xx_dxe_write_register(wcn,
925 		WCN36XX_DXE_REG_CTL_RX_L,
926 		WCN36XX_DXE_CH_DEFAULT_CTL_RX_L);
927 
928 	/* Enable channel interrupts */
929 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_L);
930 
931 	/***************************************/
932 	/* Init descriptors for RX HIGH channel */
933 	/***************************************/
934 	ret = wcn36xx_dxe_init_descs(wcn->dev, &wcn->dxe_rx_h_ch);
935 	if (ret) {
936 		dev_err(wcn->dev, "Error allocating descriptor\n");
937 		goto out_err_rxh_ch;
938 	}
939 
940 	/* For RX we need to prealocat buffers */
941 	wcn36xx_dxe_ch_alloc_skb(wcn, &wcn->dxe_rx_h_ch);
942 
943 	/* Write chanel head to a NEXT register */
944 	wcn36xx_dxe_write_register(wcn, WCN36XX_DXE_CH_NEXT_DESC_ADDR_RX_H,
945 		wcn->dxe_rx_h_ch.head_blk_ctl->desc_phy_addr);
946 
947 	/* Write DMA source address */
948 	wcn36xx_dxe_write_register(wcn,
949 		WCN36XX_DXE_CH_SRC_ADDR_RX_H,
950 		WCN36XX_DXE_WQ_RX_H);
951 
952 	/* Program preallocated destination address */
953 	wcn36xx_dxe_write_register(wcn,
954 		WCN36XX_DXE_CH_DEST_ADDR_RX_H,
955 		 wcn->dxe_rx_h_ch.head_blk_ctl->desc->phy_next_l);
956 
957 	/* Enable default control registers */
958 	wcn36xx_dxe_write_register(wcn,
959 		WCN36XX_DXE_REG_CTL_RX_H,
960 		WCN36XX_DXE_CH_DEFAULT_CTL_RX_H);
961 
962 	/* Enable channel interrupts */
963 	wcn36xx_dxe_enable_ch_int(wcn, WCN36XX_INT_MASK_CHAN_RX_H);
964 
965 	ret = wcn36xx_dxe_request_irqs(wcn);
966 	if (ret < 0)
967 		goto out_err_irq;
968 
969 	timer_setup(&wcn->tx_ack_timer, wcn36xx_dxe_tx_timer, 0);
970 
971 	return 0;
972 
973 out_err_irq:
974 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_rx_h_ch);
975 out_err_rxh_ch:
976 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_rx_l_ch);
977 out_err_rxl_ch:
978 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_tx_h_ch);
979 out_err_txh_ch:
980 	wcn36xx_dxe_deinit_descs(wcn->dev, &wcn->dxe_tx_l_ch);
981 
982 	return ret;
983 }
984 
985 void wcn36xx_dxe_deinit(struct wcn36xx *wcn)
986 {
987 	free_irq(wcn->tx_irq, wcn);
988 	free_irq(wcn->rx_irq, wcn);
989 	del_timer(&wcn->tx_ack_timer);
990 
991 	if (wcn->tx_ack_skb) {
992 		ieee80211_tx_status_irqsafe(wcn->hw, wcn->tx_ack_skb);
993 		wcn->tx_ack_skb = NULL;
994 	}
995 
996 	wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_l_ch);
997 	wcn36xx_dxe_ch_free_skbs(wcn, &wcn->dxe_rx_h_ch);
998 }
999