xref: /linux/drivers/net/ethernet/mediatek/mtk_wed_wo.c (revision 4b660dbd9ee2059850fd30e0df420ca7a38a1856)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (C) 2022 MediaTek Inc.
3  *
4  * Author: Lorenzo Bianconi <lorenzo@kernel.org>
5  *	   Sujuan Chen <sujuan.chen@mediatek.com>
6  */
7 
8 #include <linux/kernel.h>
9 #include <linux/dma-mapping.h>
10 #include <linux/interrupt.h>
11 #include <linux/mfd/syscon.h>
12 #include <linux/of.h>
13 #include <linux/of_irq.h>
14 #include <linux/bitfield.h>
15 
16 #include "mtk_wed.h"
17 #include "mtk_wed_regs.h"
18 #include "mtk_wed_wo.h"
19 
20 static u32
21 mtk_wed_mmio_r32(struct mtk_wed_wo *wo, u32 reg)
22 {
23 	u32 val;
24 
25 	if (regmap_read(wo->mmio.regs, reg, &val))
26 		val = ~0;
27 
28 	return val;
29 }
30 
31 static void
32 mtk_wed_mmio_w32(struct mtk_wed_wo *wo, u32 reg, u32 val)
33 {
34 	regmap_write(wo->mmio.regs, reg, val);
35 }
36 
37 static u32
38 mtk_wed_wo_get_isr(struct mtk_wed_wo *wo)
39 {
40 	u32 val = mtk_wed_mmio_r32(wo, MTK_WED_WO_CCIF_RCHNUM);
41 
42 	return val & MTK_WED_WO_CCIF_RCHNUM_MASK;
43 }
44 
45 static void
46 mtk_wed_wo_set_isr(struct mtk_wed_wo *wo, u32 mask)
47 {
48 	mtk_wed_mmio_w32(wo, MTK_WED_WO_CCIF_IRQ0_MASK, mask);
49 }
50 
51 static void
52 mtk_wed_wo_set_ack(struct mtk_wed_wo *wo, u32 mask)
53 {
54 	mtk_wed_mmio_w32(wo, MTK_WED_WO_CCIF_ACK, mask);
55 }
56 
57 static void
58 mtk_wed_wo_set_isr_mask(struct mtk_wed_wo *wo, u32 mask, u32 val, bool set)
59 {
60 	unsigned long flags;
61 
62 	spin_lock_irqsave(&wo->mmio.lock, flags);
63 	wo->mmio.irq_mask &= ~mask;
64 	wo->mmio.irq_mask |= val;
65 	if (set)
66 		mtk_wed_wo_set_isr(wo, wo->mmio.irq_mask);
67 	spin_unlock_irqrestore(&wo->mmio.lock, flags);
68 }
69 
70 static void
71 mtk_wed_wo_irq_enable(struct mtk_wed_wo *wo, u32 mask)
72 {
73 	mtk_wed_wo_set_isr_mask(wo, 0, mask, false);
74 	tasklet_schedule(&wo->mmio.irq_tasklet);
75 }
76 
77 static void
78 mtk_wed_wo_irq_disable(struct mtk_wed_wo *wo, u32 mask)
79 {
80 	mtk_wed_wo_set_isr_mask(wo, mask, 0, true);
81 }
82 
83 static void
84 mtk_wed_wo_kickout(struct mtk_wed_wo *wo)
85 {
86 	mtk_wed_mmio_w32(wo, MTK_WED_WO_CCIF_BUSY, 1 << MTK_WED_WO_TXCH_NUM);
87 	mtk_wed_mmio_w32(wo, MTK_WED_WO_CCIF_TCHNUM, MTK_WED_WO_TXCH_NUM);
88 }
89 
90 static void
91 mtk_wed_wo_queue_kick(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q,
92 		      u32 val)
93 {
94 	wmb();
95 	mtk_wed_mmio_w32(wo, q->regs.cpu_idx, val);
96 }
97 
98 static void *
99 mtk_wed_wo_dequeue(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q, u32 *len,
100 		   bool flush)
101 {
102 	int buf_len = SKB_WITH_OVERHEAD(q->buf_size);
103 	int index = (q->tail + 1) % q->n_desc;
104 	struct mtk_wed_wo_queue_entry *entry;
105 	struct mtk_wed_wo_queue_desc *desc;
106 	void *buf;
107 
108 	if (!q->queued)
109 		return NULL;
110 
111 	if (flush)
112 		q->desc[index].ctrl |= cpu_to_le32(MTK_WED_WO_CTL_DMA_DONE);
113 	else if (!(q->desc[index].ctrl & cpu_to_le32(MTK_WED_WO_CTL_DMA_DONE)))
114 		return NULL;
115 
116 	q->tail = index;
117 	q->queued--;
118 
119 	desc = &q->desc[index];
120 	entry = &q->entry[index];
121 	buf = entry->buf;
122 	if (len)
123 		*len = FIELD_GET(MTK_WED_WO_CTL_SD_LEN0,
124 				 le32_to_cpu(READ_ONCE(desc->ctrl)));
125 	if (buf)
126 		dma_unmap_single(wo->hw->dev, entry->addr, buf_len,
127 				 DMA_FROM_DEVICE);
128 	entry->buf = NULL;
129 
130 	return buf;
131 }
132 
133 static int
134 mtk_wed_wo_queue_refill(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q,
135 			bool rx)
136 {
137 	enum dma_data_direction dir = rx ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
138 	int n_buf = 0;
139 
140 	while (q->queued < q->n_desc) {
141 		struct mtk_wed_wo_queue_entry *entry;
142 		dma_addr_t addr;
143 		void *buf;
144 
145 		buf = page_frag_alloc(&q->cache, q->buf_size,
146 				      GFP_ATOMIC | GFP_DMA32);
147 		if (!buf)
148 			break;
149 
150 		addr = dma_map_single(wo->hw->dev, buf, q->buf_size, dir);
151 		if (unlikely(dma_mapping_error(wo->hw->dev, addr))) {
152 			skb_free_frag(buf);
153 			break;
154 		}
155 
156 		q->head = (q->head + 1) % q->n_desc;
157 		entry = &q->entry[q->head];
158 		entry->addr = addr;
159 		entry->len = q->buf_size;
160 		q->entry[q->head].buf = buf;
161 
162 		if (rx) {
163 			struct mtk_wed_wo_queue_desc *desc = &q->desc[q->head];
164 			u32 ctrl = MTK_WED_WO_CTL_LAST_SEC0 |
165 				   FIELD_PREP(MTK_WED_WO_CTL_SD_LEN0,
166 					      entry->len);
167 
168 			WRITE_ONCE(desc->buf0, cpu_to_le32(addr));
169 			WRITE_ONCE(desc->ctrl, cpu_to_le32(ctrl));
170 		}
171 		q->queued++;
172 		n_buf++;
173 	}
174 
175 	return n_buf;
176 }
177 
178 static void
179 mtk_wed_wo_rx_complete(struct mtk_wed_wo *wo)
180 {
181 	mtk_wed_wo_set_ack(wo, MTK_WED_WO_RXCH_INT_MASK);
182 	mtk_wed_wo_irq_enable(wo, MTK_WED_WO_RXCH_INT_MASK);
183 }
184 
185 static void
186 mtk_wed_wo_rx_run_queue(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q)
187 {
188 	for (;;) {
189 		struct mtk_wed_mcu_hdr *hdr;
190 		struct sk_buff *skb;
191 		void *data;
192 		u32 len;
193 
194 		data = mtk_wed_wo_dequeue(wo, q, &len, false);
195 		if (!data)
196 			break;
197 
198 		skb = build_skb(data, q->buf_size);
199 		if (!skb) {
200 			skb_free_frag(data);
201 			continue;
202 		}
203 
204 		__skb_put(skb, len);
205 		if (mtk_wed_mcu_check_msg(wo, skb)) {
206 			dev_kfree_skb(skb);
207 			continue;
208 		}
209 
210 		hdr = (struct mtk_wed_mcu_hdr *)skb->data;
211 		if (hdr->flag & cpu_to_le16(MTK_WED_WARP_CMD_FLAG_RSP))
212 			mtk_wed_mcu_rx_event(wo, skb);
213 		else
214 			mtk_wed_mcu_rx_unsolicited_event(wo, skb);
215 	}
216 
217 	if (mtk_wed_wo_queue_refill(wo, q, true)) {
218 		u32 index = (q->head - 1) % q->n_desc;
219 
220 		mtk_wed_wo_queue_kick(wo, q, index);
221 	}
222 }
223 
224 static irqreturn_t
225 mtk_wed_wo_irq_handler(int irq, void *data)
226 {
227 	struct mtk_wed_wo *wo = data;
228 
229 	mtk_wed_wo_set_isr(wo, 0);
230 	tasklet_schedule(&wo->mmio.irq_tasklet);
231 
232 	return IRQ_HANDLED;
233 }
234 
235 static void mtk_wed_wo_irq_tasklet(struct tasklet_struct *t)
236 {
237 	struct mtk_wed_wo *wo = from_tasklet(wo, t, mmio.irq_tasklet);
238 	u32 intr, mask;
239 
240 	/* disable interrupts */
241 	mtk_wed_wo_set_isr(wo, 0);
242 
243 	intr = mtk_wed_wo_get_isr(wo);
244 	intr &= wo->mmio.irq_mask;
245 	mask = intr & (MTK_WED_WO_RXCH_INT_MASK | MTK_WED_WO_EXCEPTION_INT_MASK);
246 	mtk_wed_wo_irq_disable(wo, mask);
247 
248 	if (intr & MTK_WED_WO_RXCH_INT_MASK) {
249 		mtk_wed_wo_rx_run_queue(wo, &wo->q_rx);
250 		mtk_wed_wo_rx_complete(wo);
251 	}
252 }
253 
254 /* mtk wed wo hw queues */
255 
256 static int
257 mtk_wed_wo_queue_alloc(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q,
258 		       int n_desc, int buf_size, int index,
259 		       struct mtk_wed_wo_queue_regs *regs)
260 {
261 	q->regs = *regs;
262 	q->n_desc = n_desc;
263 	q->buf_size = buf_size;
264 
265 	q->desc = dmam_alloc_coherent(wo->hw->dev, n_desc * sizeof(*q->desc),
266 				      &q->desc_dma, GFP_KERNEL);
267 	if (!q->desc)
268 		return -ENOMEM;
269 
270 	q->entry = devm_kzalloc(wo->hw->dev, n_desc * sizeof(*q->entry),
271 				GFP_KERNEL);
272 	if (!q->entry)
273 		return -ENOMEM;
274 
275 	return 0;
276 }
277 
278 static void
279 mtk_wed_wo_queue_free(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q)
280 {
281 	mtk_wed_mmio_w32(wo, q->regs.cpu_idx, 0);
282 	dma_free_coherent(wo->hw->dev, q->n_desc * sizeof(*q->desc), q->desc,
283 			  q->desc_dma);
284 }
285 
286 static void
287 mtk_wed_wo_queue_tx_clean(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q)
288 {
289 	int i;
290 
291 	for (i = 0; i < q->n_desc; i++) {
292 		struct mtk_wed_wo_queue_entry *entry = &q->entry[i];
293 
294 		if (!entry->buf)
295 			continue;
296 
297 		dma_unmap_single(wo->hw->dev, entry->addr, entry->len,
298 				 DMA_TO_DEVICE);
299 		skb_free_frag(entry->buf);
300 		entry->buf = NULL;
301 	}
302 
303 	page_frag_cache_drain(&q->cache);
304 }
305 
306 static void
307 mtk_wed_wo_queue_rx_clean(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q)
308 {
309 	for (;;) {
310 		void *buf = mtk_wed_wo_dequeue(wo, q, NULL, true);
311 
312 		if (!buf)
313 			break;
314 
315 		skb_free_frag(buf);
316 	}
317 
318 	page_frag_cache_drain(&q->cache);
319 }
320 
321 static void
322 mtk_wed_wo_queue_reset(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q)
323 {
324 	mtk_wed_mmio_w32(wo, q->regs.cpu_idx, 0);
325 	mtk_wed_mmio_w32(wo, q->regs.desc_base, q->desc_dma);
326 	mtk_wed_mmio_w32(wo, q->regs.ring_size, q->n_desc);
327 }
328 
329 int mtk_wed_wo_queue_tx_skb(struct mtk_wed_wo *wo, struct mtk_wed_wo_queue *q,
330 			    struct sk_buff *skb)
331 {
332 	struct mtk_wed_wo_queue_entry *entry;
333 	struct mtk_wed_wo_queue_desc *desc;
334 	int ret = 0, index;
335 	u32 ctrl;
336 
337 	q->tail = mtk_wed_mmio_r32(wo, q->regs.dma_idx);
338 	index = (q->head + 1) % q->n_desc;
339 	if (q->tail == index) {
340 		ret = -ENOMEM;
341 		goto out;
342 	}
343 
344 	entry = &q->entry[index];
345 	if (skb->len > entry->len) {
346 		ret = -ENOMEM;
347 		goto out;
348 	}
349 
350 	desc = &q->desc[index];
351 	q->head = index;
352 
353 	dma_sync_single_for_cpu(wo->hw->dev, entry->addr, skb->len,
354 				DMA_TO_DEVICE);
355 	memcpy(entry->buf, skb->data, skb->len);
356 	dma_sync_single_for_device(wo->hw->dev, entry->addr, skb->len,
357 				   DMA_TO_DEVICE);
358 
359 	ctrl = FIELD_PREP(MTK_WED_WO_CTL_SD_LEN0, skb->len) |
360 	       MTK_WED_WO_CTL_LAST_SEC0 | MTK_WED_WO_CTL_DMA_DONE;
361 	WRITE_ONCE(desc->buf0, cpu_to_le32(entry->addr));
362 	WRITE_ONCE(desc->ctrl, cpu_to_le32(ctrl));
363 
364 	mtk_wed_wo_queue_kick(wo, q, q->head);
365 	mtk_wed_wo_kickout(wo);
366 out:
367 	dev_kfree_skb(skb);
368 
369 	return ret;
370 }
371 
372 static int
373 mtk_wed_wo_exception_init(struct mtk_wed_wo *wo)
374 {
375 	return 0;
376 }
377 
378 static int
379 mtk_wed_wo_hardware_init(struct mtk_wed_wo *wo)
380 {
381 	struct mtk_wed_wo_queue_regs regs;
382 	struct device_node *np;
383 	int ret;
384 
385 	np = of_parse_phandle(wo->hw->node, "mediatek,wo-ccif", 0);
386 	if (!np)
387 		return -ENODEV;
388 
389 	wo->mmio.regs = syscon_regmap_lookup_by_phandle(np, NULL);
390 	if (IS_ERR(wo->mmio.regs)) {
391 		ret = PTR_ERR(wo->mmio.regs);
392 		goto error_put;
393 	}
394 
395 	wo->mmio.irq = irq_of_parse_and_map(np, 0);
396 	wo->mmio.irq_mask = MTK_WED_WO_ALL_INT_MASK;
397 	spin_lock_init(&wo->mmio.lock);
398 	tasklet_setup(&wo->mmio.irq_tasklet, mtk_wed_wo_irq_tasklet);
399 
400 	ret = devm_request_irq(wo->hw->dev, wo->mmio.irq,
401 			       mtk_wed_wo_irq_handler, IRQF_TRIGGER_HIGH,
402 			       KBUILD_MODNAME, wo);
403 	if (ret)
404 		goto error;
405 
406 	regs.desc_base = MTK_WED_WO_CCIF_DUMMY1;
407 	regs.ring_size = MTK_WED_WO_CCIF_DUMMY2;
408 	regs.dma_idx = MTK_WED_WO_CCIF_SHADOW4;
409 	regs.cpu_idx = MTK_WED_WO_CCIF_DUMMY3;
410 
411 	ret = mtk_wed_wo_queue_alloc(wo, &wo->q_tx, MTK_WED_WO_RING_SIZE,
412 				     MTK_WED_WO_CMD_LEN, MTK_WED_WO_TXCH_NUM,
413 				     &regs);
414 	if (ret)
415 		goto error;
416 
417 	mtk_wed_wo_queue_refill(wo, &wo->q_tx, false);
418 	mtk_wed_wo_queue_reset(wo, &wo->q_tx);
419 
420 	regs.desc_base = MTK_WED_WO_CCIF_DUMMY5;
421 	regs.ring_size = MTK_WED_WO_CCIF_DUMMY6;
422 	regs.dma_idx = MTK_WED_WO_CCIF_SHADOW8;
423 	regs.cpu_idx = MTK_WED_WO_CCIF_DUMMY7;
424 
425 	ret = mtk_wed_wo_queue_alloc(wo, &wo->q_rx, MTK_WED_WO_RING_SIZE,
426 				     MTK_WED_WO_CMD_LEN, MTK_WED_WO_RXCH_NUM,
427 				     &regs);
428 	if (ret)
429 		goto error;
430 
431 	mtk_wed_wo_queue_refill(wo, &wo->q_rx, true);
432 	mtk_wed_wo_queue_reset(wo, &wo->q_rx);
433 
434 	/* rx queue irqmask */
435 	mtk_wed_wo_set_isr(wo, wo->mmio.irq_mask);
436 
437 	return 0;
438 
439 error:
440 	devm_free_irq(wo->hw->dev, wo->mmio.irq, wo);
441 error_put:
442 	of_node_put(np);
443 	return ret;
444 }
445 
446 static void
447 mtk_wed_wo_hw_deinit(struct mtk_wed_wo *wo)
448 {
449 	/* disable interrupts */
450 	mtk_wed_wo_set_isr(wo, 0);
451 
452 	tasklet_disable(&wo->mmio.irq_tasklet);
453 
454 	disable_irq(wo->mmio.irq);
455 	devm_free_irq(wo->hw->dev, wo->mmio.irq, wo);
456 
457 	mtk_wed_wo_queue_tx_clean(wo, &wo->q_tx);
458 	mtk_wed_wo_queue_rx_clean(wo, &wo->q_rx);
459 	mtk_wed_wo_queue_free(wo, &wo->q_tx);
460 	mtk_wed_wo_queue_free(wo, &wo->q_rx);
461 }
462 
463 int mtk_wed_wo_init(struct mtk_wed_hw *hw)
464 {
465 	struct mtk_wed_wo *wo;
466 	int ret;
467 
468 	wo = devm_kzalloc(hw->dev, sizeof(*wo), GFP_KERNEL);
469 	if (!wo)
470 		return -ENOMEM;
471 
472 	hw->wed_wo = wo;
473 	wo->hw = hw;
474 
475 	ret = mtk_wed_wo_hardware_init(wo);
476 	if (ret)
477 		return ret;
478 
479 	ret = mtk_wed_mcu_init(wo);
480 	if (ret)
481 		return ret;
482 
483 	return mtk_wed_wo_exception_init(wo);
484 }
485 
486 void mtk_wed_wo_deinit(struct mtk_wed_hw *hw)
487 {
488 	struct mtk_wed_wo *wo = hw->wed_wo;
489 
490 	mtk_wed_wo_hw_deinit(wo);
491 }
492