1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (C) 2021 Gerhard Engleder <gerhard@engleder-embedded.com> */
3 
4 /* TSN endpoint Ethernet MAC driver
5  *
6  * The TSN endpoint Ethernet MAC is a FPGA based network device for real-time
7  * communication. It is designed for endpoints within TSN (Time Sensitive
8  * Networking) networks; e.g., for PLCs in the industrial automation case.
9  *
10  * It supports multiple TX/RX queue pairs. The first TX/RX queue pair is used
11  * by the driver.
12  *
13  * More information can be found here:
14  * - www.embedded-experts.at/tsn
15  * - www.engleder-embedded.com
16  */
17 
18 #include "tsnep.h"
19 #include "tsnep_hw.h"
20 
21 #include <linux/module.h>
22 #include <linux/of.h>
23 #include <linux/of_net.h>
24 #include <linux/of_mdio.h>
25 #include <linux/interrupt.h>
26 #include <linux/etherdevice.h>
27 #include <linux/phy.h>
28 #include <linux/iopoll.h>
29 
30 #define TSNEP_SKB_PAD (NET_SKB_PAD + NET_IP_ALIGN)
31 #define TSNEP_HEADROOM ALIGN(TSNEP_SKB_PAD, 4)
32 #define TSNEP_MAX_RX_BUF_SIZE (PAGE_SIZE - TSNEP_HEADROOM - \
33 			       SKB_DATA_ALIGN(sizeof(struct skb_shared_info)))
34 
35 #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
36 #define DMA_ADDR_HIGH(dma_addr) ((u32)(((dma_addr) >> 32) & 0xFFFFFFFF))
37 #else
38 #define DMA_ADDR_HIGH(dma_addr) ((u32)(0))
39 #endif
40 #define DMA_ADDR_LOW(dma_addr) ((u32)((dma_addr) & 0xFFFFFFFF))
41 
42 #define TSNEP_COALESCE_USECS_DEFAULT 64
43 #define TSNEP_COALESCE_USECS_MAX     ((ECM_INT_DELAY_MASK >> ECM_INT_DELAY_SHIFT) * \
44 				      ECM_INT_DELAY_BASE_US + ECM_INT_DELAY_BASE_US - 1)
45 
46 static void tsnep_enable_irq(struct tsnep_adapter *adapter, u32 mask)
47 {
48 	iowrite32(mask, adapter->addr + ECM_INT_ENABLE);
49 }
50 
51 static void tsnep_disable_irq(struct tsnep_adapter *adapter, u32 mask)
52 {
53 	mask |= ECM_INT_DISABLE;
54 	iowrite32(mask, adapter->addr + ECM_INT_ENABLE);
55 }
56 
57 static irqreturn_t tsnep_irq(int irq, void *arg)
58 {
59 	struct tsnep_adapter *adapter = arg;
60 	u32 active = ioread32(adapter->addr + ECM_INT_ACTIVE);
61 
62 	/* acknowledge interrupt */
63 	if (active != 0)
64 		iowrite32(active, adapter->addr + ECM_INT_ACKNOWLEDGE);
65 
66 	/* handle link interrupt */
67 	if ((active & ECM_INT_LINK) != 0)
68 		phy_mac_interrupt(adapter->netdev->phydev);
69 
70 	/* handle TX/RX queue 0 interrupt */
71 	if ((active & adapter->queue[0].irq_mask) != 0) {
72 		tsnep_disable_irq(adapter, adapter->queue[0].irq_mask);
73 		napi_schedule(&adapter->queue[0].napi);
74 	}
75 
76 	return IRQ_HANDLED;
77 }
78 
79 static irqreturn_t tsnep_irq_txrx(int irq, void *arg)
80 {
81 	struct tsnep_queue *queue = arg;
82 
83 	/* handle TX/RX queue interrupt */
84 	tsnep_disable_irq(queue->adapter, queue->irq_mask);
85 	napi_schedule(&queue->napi);
86 
87 	return IRQ_HANDLED;
88 }
89 
90 int tsnep_set_irq_coalesce(struct tsnep_queue *queue, u32 usecs)
91 {
92 	if (usecs > TSNEP_COALESCE_USECS_MAX)
93 		return -ERANGE;
94 
95 	usecs /= ECM_INT_DELAY_BASE_US;
96 	usecs <<= ECM_INT_DELAY_SHIFT;
97 	usecs &= ECM_INT_DELAY_MASK;
98 
99 	queue->irq_delay &= ~ECM_INT_DELAY_MASK;
100 	queue->irq_delay |= usecs;
101 	iowrite8(queue->irq_delay, queue->irq_delay_addr);
102 
103 	return 0;
104 }
105 
106 u32 tsnep_get_irq_coalesce(struct tsnep_queue *queue)
107 {
108 	u32 usecs;
109 
110 	usecs = (queue->irq_delay & ECM_INT_DELAY_MASK);
111 	usecs >>= ECM_INT_DELAY_SHIFT;
112 	usecs *= ECM_INT_DELAY_BASE_US;
113 
114 	return usecs;
115 }
116 
117 static int tsnep_mdiobus_read(struct mii_bus *bus, int addr, int regnum)
118 {
119 	struct tsnep_adapter *adapter = bus->priv;
120 	u32 md;
121 	int retval;
122 
123 	if (regnum & MII_ADDR_C45)
124 		return -EOPNOTSUPP;
125 
126 	md = ECM_MD_READ;
127 	if (!adapter->suppress_preamble)
128 		md |= ECM_MD_PREAMBLE;
129 	md |= (regnum << ECM_MD_ADDR_SHIFT) & ECM_MD_ADDR_MASK;
130 	md |= (addr << ECM_MD_PHY_ADDR_SHIFT) & ECM_MD_PHY_ADDR_MASK;
131 	iowrite32(md, adapter->addr + ECM_MD_CONTROL);
132 	retval = readl_poll_timeout_atomic(adapter->addr + ECM_MD_STATUS, md,
133 					   !(md & ECM_MD_BUSY), 16, 1000);
134 	if (retval != 0)
135 		return retval;
136 
137 	return (md & ECM_MD_DATA_MASK) >> ECM_MD_DATA_SHIFT;
138 }
139 
140 static int tsnep_mdiobus_write(struct mii_bus *bus, int addr, int regnum,
141 			       u16 val)
142 {
143 	struct tsnep_adapter *adapter = bus->priv;
144 	u32 md;
145 	int retval;
146 
147 	if (regnum & MII_ADDR_C45)
148 		return -EOPNOTSUPP;
149 
150 	md = ECM_MD_WRITE;
151 	if (!adapter->suppress_preamble)
152 		md |= ECM_MD_PREAMBLE;
153 	md |= (regnum << ECM_MD_ADDR_SHIFT) & ECM_MD_ADDR_MASK;
154 	md |= (addr << ECM_MD_PHY_ADDR_SHIFT) & ECM_MD_PHY_ADDR_MASK;
155 	md |= ((u32)val << ECM_MD_DATA_SHIFT) & ECM_MD_DATA_MASK;
156 	iowrite32(md, adapter->addr + ECM_MD_CONTROL);
157 	retval = readl_poll_timeout_atomic(adapter->addr + ECM_MD_STATUS, md,
158 					   !(md & ECM_MD_BUSY), 16, 1000);
159 	if (retval != 0)
160 		return retval;
161 
162 	return 0;
163 }
164 
165 static void tsnep_set_link_mode(struct tsnep_adapter *adapter)
166 {
167 	u32 mode;
168 
169 	switch (adapter->phydev->speed) {
170 	case SPEED_100:
171 		mode = ECM_LINK_MODE_100;
172 		break;
173 	case SPEED_1000:
174 		mode = ECM_LINK_MODE_1000;
175 		break;
176 	default:
177 		mode = ECM_LINK_MODE_OFF;
178 		break;
179 	}
180 	iowrite32(mode, adapter->addr + ECM_STATUS);
181 }
182 
183 static void tsnep_phy_link_status_change(struct net_device *netdev)
184 {
185 	struct tsnep_adapter *adapter = netdev_priv(netdev);
186 	struct phy_device *phydev = netdev->phydev;
187 
188 	if (phydev->link)
189 		tsnep_set_link_mode(adapter);
190 
191 	phy_print_status(netdev->phydev);
192 }
193 
194 static int tsnep_phy_loopback(struct tsnep_adapter *adapter, bool enable)
195 {
196 	int retval;
197 
198 	retval = phy_loopback(adapter->phydev, enable);
199 
200 	/* PHY link state change is not signaled if loopback is enabled, it
201 	 * would delay a working loopback anyway, let's ensure that loopback
202 	 * is working immediately by setting link mode directly
203 	 */
204 	if (!retval && enable)
205 		tsnep_set_link_mode(adapter);
206 
207 	return retval;
208 }
209 
210 static int tsnep_phy_open(struct tsnep_adapter *adapter)
211 {
212 	struct phy_device *phydev;
213 	struct ethtool_eee ethtool_eee;
214 	int retval;
215 
216 	retval = phy_connect_direct(adapter->netdev, adapter->phydev,
217 				    tsnep_phy_link_status_change,
218 				    adapter->phy_mode);
219 	if (retval)
220 		return retval;
221 	phydev = adapter->netdev->phydev;
222 
223 	/* MAC supports only 100Mbps|1000Mbps full duplex
224 	 * SPE (Single Pair Ethernet) is also an option but not implemented yet
225 	 */
226 	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_10baseT_Half_BIT);
227 	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_10baseT_Full_BIT);
228 	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_100baseT_Half_BIT);
229 	phy_remove_link_mode(phydev, ETHTOOL_LINK_MODE_1000baseT_Half_BIT);
230 
231 	/* disable EEE autoneg, EEE not supported by TSNEP */
232 	memset(&ethtool_eee, 0, sizeof(ethtool_eee));
233 	phy_ethtool_set_eee(adapter->phydev, &ethtool_eee);
234 
235 	adapter->phydev->irq = PHY_MAC_INTERRUPT;
236 	phy_start(adapter->phydev);
237 
238 	return 0;
239 }
240 
241 static void tsnep_phy_close(struct tsnep_adapter *adapter)
242 {
243 	phy_stop(adapter->netdev->phydev);
244 	phy_disconnect(adapter->netdev->phydev);
245 	adapter->netdev->phydev = NULL;
246 }
247 
248 static void tsnep_tx_ring_cleanup(struct tsnep_tx *tx)
249 {
250 	struct device *dmadev = tx->adapter->dmadev;
251 	int i;
252 
253 	memset(tx->entry, 0, sizeof(tx->entry));
254 
255 	for (i = 0; i < TSNEP_RING_PAGE_COUNT; i++) {
256 		if (tx->page[i]) {
257 			dma_free_coherent(dmadev, PAGE_SIZE, tx->page[i],
258 					  tx->page_dma[i]);
259 			tx->page[i] = NULL;
260 			tx->page_dma[i] = 0;
261 		}
262 	}
263 }
264 
265 static int tsnep_tx_ring_init(struct tsnep_tx *tx)
266 {
267 	struct device *dmadev = tx->adapter->dmadev;
268 	struct tsnep_tx_entry *entry;
269 	struct tsnep_tx_entry *next_entry;
270 	int i, j;
271 	int retval;
272 
273 	for (i = 0; i < TSNEP_RING_PAGE_COUNT; i++) {
274 		tx->page[i] =
275 			dma_alloc_coherent(dmadev, PAGE_SIZE, &tx->page_dma[i],
276 					   GFP_KERNEL);
277 		if (!tx->page[i]) {
278 			retval = -ENOMEM;
279 			goto alloc_failed;
280 		}
281 		for (j = 0; j < TSNEP_RING_ENTRIES_PER_PAGE; j++) {
282 			entry = &tx->entry[TSNEP_RING_ENTRIES_PER_PAGE * i + j];
283 			entry->desc_wb = (struct tsnep_tx_desc_wb *)
284 				(((u8 *)tx->page[i]) + TSNEP_DESC_SIZE * j);
285 			entry->desc = (struct tsnep_tx_desc *)
286 				(((u8 *)entry->desc_wb) + TSNEP_DESC_OFFSET);
287 			entry->desc_dma = tx->page_dma[i] + TSNEP_DESC_SIZE * j;
288 		}
289 	}
290 	for (i = 0; i < TSNEP_RING_SIZE; i++) {
291 		entry = &tx->entry[i];
292 		next_entry = &tx->entry[(i + 1) % TSNEP_RING_SIZE];
293 		entry->desc->next = __cpu_to_le64(next_entry->desc_dma);
294 	}
295 
296 	return 0;
297 
298 alloc_failed:
299 	tsnep_tx_ring_cleanup(tx);
300 	return retval;
301 }
302 
303 static void tsnep_tx_activate(struct tsnep_tx *tx, int index, int length,
304 			      bool last)
305 {
306 	struct tsnep_tx_entry *entry = &tx->entry[index];
307 
308 	entry->properties = 0;
309 	if (entry->skb) {
310 		entry->properties = length & TSNEP_DESC_LENGTH_MASK;
311 		entry->properties |= TSNEP_DESC_INTERRUPT_FLAG;
312 		if (skb_shinfo(entry->skb)->tx_flags & SKBTX_IN_PROGRESS)
313 			entry->properties |= TSNEP_DESC_EXTENDED_WRITEBACK_FLAG;
314 
315 		/* toggle user flag to prevent false acknowledge
316 		 *
317 		 * Only the first fragment is acknowledged. For all other
318 		 * fragments no acknowledge is done and the last written owner
319 		 * counter stays in the writeback descriptor. Therefore, it is
320 		 * possible that the last written owner counter is identical to
321 		 * the new incremented owner counter and a false acknowledge is
322 		 * detected before the real acknowledge has been done by
323 		 * hardware.
324 		 *
325 		 * The user flag is used to prevent this situation. The user
326 		 * flag is copied to the writeback descriptor by the hardware
327 		 * and is used as additional acknowledge data. By toggeling the
328 		 * user flag only for the first fragment (which is
329 		 * acknowledged), it is guaranteed that the last acknowledge
330 		 * done for this descriptor has used a different user flag and
331 		 * cannot be detected as false acknowledge.
332 		 */
333 		entry->owner_user_flag = !entry->owner_user_flag;
334 	}
335 	if (last)
336 		entry->properties |= TSNEP_TX_DESC_LAST_FRAGMENT_FLAG;
337 	if (index == tx->increment_owner_counter) {
338 		tx->owner_counter++;
339 		if (tx->owner_counter == 4)
340 			tx->owner_counter = 1;
341 		tx->increment_owner_counter--;
342 		if (tx->increment_owner_counter < 0)
343 			tx->increment_owner_counter = TSNEP_RING_SIZE - 1;
344 	}
345 	entry->properties |=
346 		(tx->owner_counter << TSNEP_DESC_OWNER_COUNTER_SHIFT) &
347 		TSNEP_DESC_OWNER_COUNTER_MASK;
348 	if (entry->owner_user_flag)
349 		entry->properties |= TSNEP_TX_DESC_OWNER_USER_FLAG;
350 	entry->desc->more_properties =
351 		__cpu_to_le32(entry->len & TSNEP_DESC_LENGTH_MASK);
352 
353 	/* descriptor properties shall be written last, because valid data is
354 	 * signaled there
355 	 */
356 	dma_wmb();
357 
358 	entry->desc->properties = __cpu_to_le32(entry->properties);
359 }
360 
361 static int tsnep_tx_desc_available(struct tsnep_tx *tx)
362 {
363 	if (tx->read <= tx->write)
364 		return TSNEP_RING_SIZE - tx->write + tx->read - 1;
365 	else
366 		return tx->read - tx->write - 1;
367 }
368 
369 static int tsnep_tx_map(struct sk_buff *skb, struct tsnep_tx *tx, int count)
370 {
371 	struct device *dmadev = tx->adapter->dmadev;
372 	struct tsnep_tx_entry *entry;
373 	unsigned int len;
374 	dma_addr_t dma;
375 	int map_len = 0;
376 	int i;
377 
378 	for (i = 0; i < count; i++) {
379 		entry = &tx->entry[(tx->write + i) % TSNEP_RING_SIZE];
380 
381 		if (i == 0) {
382 			len = skb_headlen(skb);
383 			dma = dma_map_single(dmadev, skb->data, len,
384 					     DMA_TO_DEVICE);
385 		} else {
386 			len = skb_frag_size(&skb_shinfo(skb)->frags[i - 1]);
387 			dma = skb_frag_dma_map(dmadev,
388 					       &skb_shinfo(skb)->frags[i - 1],
389 					       0, len, DMA_TO_DEVICE);
390 		}
391 		if (dma_mapping_error(dmadev, dma))
392 			return -ENOMEM;
393 
394 		entry->len = len;
395 		dma_unmap_addr_set(entry, dma, dma);
396 
397 		entry->desc->tx = __cpu_to_le64(dma);
398 
399 		map_len += len;
400 	}
401 
402 	return map_len;
403 }
404 
405 static int tsnep_tx_unmap(struct tsnep_tx *tx, int index, int count)
406 {
407 	struct device *dmadev = tx->adapter->dmadev;
408 	struct tsnep_tx_entry *entry;
409 	int map_len = 0;
410 	int i;
411 
412 	for (i = 0; i < count; i++) {
413 		entry = &tx->entry[(index + i) % TSNEP_RING_SIZE];
414 
415 		if (entry->len) {
416 			if (i == 0)
417 				dma_unmap_single(dmadev,
418 						 dma_unmap_addr(entry, dma),
419 						 dma_unmap_len(entry, len),
420 						 DMA_TO_DEVICE);
421 			else
422 				dma_unmap_page(dmadev,
423 					       dma_unmap_addr(entry, dma),
424 					       dma_unmap_len(entry, len),
425 					       DMA_TO_DEVICE);
426 			map_len += entry->len;
427 			entry->len = 0;
428 		}
429 	}
430 
431 	return map_len;
432 }
433 
434 static netdev_tx_t tsnep_xmit_frame_ring(struct sk_buff *skb,
435 					 struct tsnep_tx *tx)
436 {
437 	unsigned long flags;
438 	int count = 1;
439 	struct tsnep_tx_entry *entry;
440 	int length;
441 	int i;
442 	int retval;
443 
444 	if (skb_shinfo(skb)->nr_frags > 0)
445 		count += skb_shinfo(skb)->nr_frags;
446 
447 	spin_lock_irqsave(&tx->lock, flags);
448 
449 	if (tsnep_tx_desc_available(tx) < count) {
450 		/* ring full, shall not happen because queue is stopped if full
451 		 * below
452 		 */
453 		netif_stop_subqueue(tx->adapter->netdev, tx->queue_index);
454 
455 		spin_unlock_irqrestore(&tx->lock, flags);
456 
457 		return NETDEV_TX_BUSY;
458 	}
459 
460 	entry = &tx->entry[tx->write];
461 	entry->skb = skb;
462 
463 	retval = tsnep_tx_map(skb, tx, count);
464 	if (retval < 0) {
465 		tsnep_tx_unmap(tx, tx->write, count);
466 		dev_kfree_skb_any(entry->skb);
467 		entry->skb = NULL;
468 
469 		tx->dropped++;
470 
471 		spin_unlock_irqrestore(&tx->lock, flags);
472 
473 		netdev_err(tx->adapter->netdev, "TX DMA map failed\n");
474 
475 		return NETDEV_TX_OK;
476 	}
477 	length = retval;
478 
479 	if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP)
480 		skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
481 
482 	for (i = 0; i < count; i++)
483 		tsnep_tx_activate(tx, (tx->write + i) % TSNEP_RING_SIZE, length,
484 				  i == (count - 1));
485 	tx->write = (tx->write + count) % TSNEP_RING_SIZE;
486 
487 	skb_tx_timestamp(skb);
488 
489 	/* descriptor properties shall be valid before hardware is notified */
490 	dma_wmb();
491 
492 	iowrite32(TSNEP_CONTROL_TX_ENABLE, tx->addr + TSNEP_CONTROL);
493 
494 	if (tsnep_tx_desc_available(tx) < (MAX_SKB_FRAGS + 1)) {
495 		/* ring can get full with next frame */
496 		netif_stop_subqueue(tx->adapter->netdev, tx->queue_index);
497 	}
498 
499 	spin_unlock_irqrestore(&tx->lock, flags);
500 
501 	return NETDEV_TX_OK;
502 }
503 
504 static bool tsnep_tx_poll(struct tsnep_tx *tx, int napi_budget)
505 {
506 	struct tsnep_tx_entry *entry;
507 	struct netdev_queue *nq;
508 	unsigned long flags;
509 	int budget = 128;
510 	int length;
511 	int count;
512 
513 	nq = netdev_get_tx_queue(tx->adapter->netdev, tx->queue_index);
514 
515 	spin_lock_irqsave(&tx->lock, flags);
516 
517 	do {
518 		if (tx->read == tx->write)
519 			break;
520 
521 		entry = &tx->entry[tx->read];
522 		if ((__le32_to_cpu(entry->desc_wb->properties) &
523 		     TSNEP_TX_DESC_OWNER_MASK) !=
524 		    (entry->properties & TSNEP_TX_DESC_OWNER_MASK))
525 			break;
526 
527 		/* descriptor properties shall be read first, because valid data
528 		 * is signaled there
529 		 */
530 		dma_rmb();
531 
532 		count = 1;
533 		if (skb_shinfo(entry->skb)->nr_frags > 0)
534 			count += skb_shinfo(entry->skb)->nr_frags;
535 
536 		length = tsnep_tx_unmap(tx, tx->read, count);
537 
538 		if ((skb_shinfo(entry->skb)->tx_flags & SKBTX_IN_PROGRESS) &&
539 		    (__le32_to_cpu(entry->desc_wb->properties) &
540 		     TSNEP_DESC_EXTENDED_WRITEBACK_FLAG)) {
541 			struct skb_shared_hwtstamps hwtstamps;
542 			u64 timestamp;
543 
544 			if (skb_shinfo(entry->skb)->tx_flags &
545 			    SKBTX_HW_TSTAMP_USE_CYCLES)
546 				timestamp =
547 					__le64_to_cpu(entry->desc_wb->counter);
548 			else
549 				timestamp =
550 					__le64_to_cpu(entry->desc_wb->timestamp);
551 
552 			memset(&hwtstamps, 0, sizeof(hwtstamps));
553 			hwtstamps.hwtstamp = ns_to_ktime(timestamp);
554 
555 			skb_tstamp_tx(entry->skb, &hwtstamps);
556 		}
557 
558 		napi_consume_skb(entry->skb, budget);
559 		entry->skb = NULL;
560 
561 		tx->read = (tx->read + count) % TSNEP_RING_SIZE;
562 
563 		tx->packets++;
564 		tx->bytes += length + ETH_FCS_LEN;
565 
566 		budget--;
567 	} while (likely(budget));
568 
569 	if ((tsnep_tx_desc_available(tx) >= ((MAX_SKB_FRAGS + 1) * 2)) &&
570 	    netif_tx_queue_stopped(nq)) {
571 		netif_tx_wake_queue(nq);
572 	}
573 
574 	spin_unlock_irqrestore(&tx->lock, flags);
575 
576 	return (budget != 0);
577 }
578 
579 static bool tsnep_tx_pending(struct tsnep_tx *tx)
580 {
581 	unsigned long flags;
582 	struct tsnep_tx_entry *entry;
583 	bool pending = false;
584 
585 	spin_lock_irqsave(&tx->lock, flags);
586 
587 	if (tx->read != tx->write) {
588 		entry = &tx->entry[tx->read];
589 		if ((__le32_to_cpu(entry->desc_wb->properties) &
590 		     TSNEP_TX_DESC_OWNER_MASK) ==
591 		    (entry->properties & TSNEP_TX_DESC_OWNER_MASK))
592 			pending = true;
593 	}
594 
595 	spin_unlock_irqrestore(&tx->lock, flags);
596 
597 	return pending;
598 }
599 
600 static int tsnep_tx_open(struct tsnep_adapter *adapter, void __iomem *addr,
601 			 int queue_index, struct tsnep_tx *tx)
602 {
603 	dma_addr_t dma;
604 	int retval;
605 
606 	memset(tx, 0, sizeof(*tx));
607 	tx->adapter = adapter;
608 	tx->addr = addr;
609 	tx->queue_index = queue_index;
610 
611 	retval = tsnep_tx_ring_init(tx);
612 	if (retval)
613 		return retval;
614 
615 	dma = tx->entry[0].desc_dma | TSNEP_RESET_OWNER_COUNTER;
616 	iowrite32(DMA_ADDR_LOW(dma), tx->addr + TSNEP_TX_DESC_ADDR_LOW);
617 	iowrite32(DMA_ADDR_HIGH(dma), tx->addr + TSNEP_TX_DESC_ADDR_HIGH);
618 	tx->owner_counter = 1;
619 	tx->increment_owner_counter = TSNEP_RING_SIZE - 1;
620 
621 	spin_lock_init(&tx->lock);
622 
623 	return 0;
624 }
625 
626 static void tsnep_tx_close(struct tsnep_tx *tx)
627 {
628 	u32 val;
629 
630 	readx_poll_timeout(ioread32, tx->addr + TSNEP_CONTROL, val,
631 			   ((val & TSNEP_CONTROL_TX_ENABLE) == 0), 10000,
632 			   1000000);
633 
634 	tsnep_tx_ring_cleanup(tx);
635 }
636 
637 static void tsnep_rx_ring_cleanup(struct tsnep_rx *rx)
638 {
639 	struct device *dmadev = rx->adapter->dmadev;
640 	struct tsnep_rx_entry *entry;
641 	int i;
642 
643 	for (i = 0; i < TSNEP_RING_SIZE; i++) {
644 		entry = &rx->entry[i];
645 		if (entry->page)
646 			page_pool_put_full_page(rx->page_pool, entry->page,
647 						false);
648 		entry->page = NULL;
649 	}
650 
651 	if (rx->page_pool)
652 		page_pool_destroy(rx->page_pool);
653 
654 	memset(rx->entry, 0, sizeof(rx->entry));
655 
656 	for (i = 0; i < TSNEP_RING_PAGE_COUNT; i++) {
657 		if (rx->page[i]) {
658 			dma_free_coherent(dmadev, PAGE_SIZE, rx->page[i],
659 					  rx->page_dma[i]);
660 			rx->page[i] = NULL;
661 			rx->page_dma[i] = 0;
662 		}
663 	}
664 }
665 
666 static int tsnep_rx_ring_init(struct tsnep_rx *rx)
667 {
668 	struct device *dmadev = rx->adapter->dmadev;
669 	struct tsnep_rx_entry *entry;
670 	struct page_pool_params pp_params = { 0 };
671 	struct tsnep_rx_entry *next_entry;
672 	int i, j;
673 	int retval;
674 
675 	for (i = 0; i < TSNEP_RING_PAGE_COUNT; i++) {
676 		rx->page[i] =
677 			dma_alloc_coherent(dmadev, PAGE_SIZE, &rx->page_dma[i],
678 					   GFP_KERNEL);
679 		if (!rx->page[i]) {
680 			retval = -ENOMEM;
681 			goto failed;
682 		}
683 		for (j = 0; j < TSNEP_RING_ENTRIES_PER_PAGE; j++) {
684 			entry = &rx->entry[TSNEP_RING_ENTRIES_PER_PAGE * i + j];
685 			entry->desc_wb = (struct tsnep_rx_desc_wb *)
686 				(((u8 *)rx->page[i]) + TSNEP_DESC_SIZE * j);
687 			entry->desc = (struct tsnep_rx_desc *)
688 				(((u8 *)entry->desc_wb) + TSNEP_DESC_OFFSET);
689 			entry->desc_dma = rx->page_dma[i] + TSNEP_DESC_SIZE * j;
690 		}
691 	}
692 
693 	pp_params.flags = PP_FLAG_DMA_MAP | PP_FLAG_DMA_SYNC_DEV;
694 	pp_params.order = 0;
695 	pp_params.pool_size = TSNEP_RING_SIZE;
696 	pp_params.nid = dev_to_node(dmadev);
697 	pp_params.dev = dmadev;
698 	pp_params.dma_dir = DMA_FROM_DEVICE;
699 	pp_params.max_len = TSNEP_MAX_RX_BUF_SIZE;
700 	pp_params.offset = TSNEP_SKB_PAD;
701 	rx->page_pool = page_pool_create(&pp_params);
702 	if (IS_ERR(rx->page_pool)) {
703 		retval = PTR_ERR(rx->page_pool);
704 		rx->page_pool = NULL;
705 		goto failed;
706 	}
707 
708 	for (i = 0; i < TSNEP_RING_SIZE; i++) {
709 		entry = &rx->entry[i];
710 		next_entry = &rx->entry[(i + 1) % TSNEP_RING_SIZE];
711 		entry->desc->next = __cpu_to_le64(next_entry->desc_dma);
712 	}
713 
714 	return 0;
715 
716 failed:
717 	tsnep_rx_ring_cleanup(rx);
718 	return retval;
719 }
720 
721 static int tsnep_rx_desc_available(struct tsnep_rx *rx)
722 {
723 	if (rx->read <= rx->write)
724 		return TSNEP_RING_SIZE - rx->write + rx->read - 1;
725 	else
726 		return rx->read - rx->write - 1;
727 }
728 
729 static void tsnep_rx_set_page(struct tsnep_rx *rx, struct tsnep_rx_entry *entry,
730 			      struct page *page)
731 {
732 	entry->page = page;
733 	entry->len = TSNEP_MAX_RX_BUF_SIZE;
734 	entry->dma = page_pool_get_dma_addr(entry->page);
735 	entry->desc->rx = __cpu_to_le64(entry->dma + TSNEP_SKB_PAD);
736 }
737 
738 static int tsnep_rx_alloc_buffer(struct tsnep_rx *rx, int index)
739 {
740 	struct tsnep_rx_entry *entry = &rx->entry[index];
741 	struct page *page;
742 
743 	page = page_pool_dev_alloc_pages(rx->page_pool);
744 	if (unlikely(!page))
745 		return -ENOMEM;
746 	tsnep_rx_set_page(rx, entry, page);
747 
748 	return 0;
749 }
750 
751 static void tsnep_rx_reuse_buffer(struct tsnep_rx *rx, int index)
752 {
753 	struct tsnep_rx_entry *entry = &rx->entry[index];
754 	struct tsnep_rx_entry *read = &rx->entry[rx->read];
755 
756 	tsnep_rx_set_page(rx, entry, read->page);
757 	read->page = NULL;
758 }
759 
760 static void tsnep_rx_activate(struct tsnep_rx *rx, int index)
761 {
762 	struct tsnep_rx_entry *entry = &rx->entry[index];
763 
764 	/* TSNEP_MAX_RX_BUF_SIZE is a multiple of 4 */
765 	entry->properties = entry->len & TSNEP_DESC_LENGTH_MASK;
766 	entry->properties |= TSNEP_DESC_INTERRUPT_FLAG;
767 	if (index == rx->increment_owner_counter) {
768 		rx->owner_counter++;
769 		if (rx->owner_counter == 4)
770 			rx->owner_counter = 1;
771 		rx->increment_owner_counter--;
772 		if (rx->increment_owner_counter < 0)
773 			rx->increment_owner_counter = TSNEP_RING_SIZE - 1;
774 	}
775 	entry->properties |=
776 		(rx->owner_counter << TSNEP_DESC_OWNER_COUNTER_SHIFT) &
777 		TSNEP_DESC_OWNER_COUNTER_MASK;
778 
779 	/* descriptor properties shall be written last, because valid data is
780 	 * signaled there
781 	 */
782 	dma_wmb();
783 
784 	entry->desc->properties = __cpu_to_le32(entry->properties);
785 }
786 
787 static int tsnep_rx_refill(struct tsnep_rx *rx, int count, bool reuse)
788 {
789 	int index;
790 	bool alloc_failed = false;
791 	bool enable = false;
792 	int i;
793 	int retval;
794 
795 	for (i = 0; i < count && !alloc_failed; i++) {
796 		index = (rx->write + i) % TSNEP_RING_SIZE;
797 
798 		retval = tsnep_rx_alloc_buffer(rx, index);
799 		if (unlikely(retval)) {
800 			rx->alloc_failed++;
801 			alloc_failed = true;
802 
803 			/* reuse only if no other allocation was successful */
804 			if (i == 0 && reuse)
805 				tsnep_rx_reuse_buffer(rx, index);
806 			else
807 				break;
808 		}
809 
810 		tsnep_rx_activate(rx, index);
811 
812 		enable = true;
813 	}
814 
815 	if (enable) {
816 		rx->write = (rx->write + i) % TSNEP_RING_SIZE;
817 
818 		/* descriptor properties shall be valid before hardware is
819 		 * notified
820 		 */
821 		dma_wmb();
822 
823 		iowrite32(TSNEP_CONTROL_RX_ENABLE, rx->addr + TSNEP_CONTROL);
824 	}
825 
826 	return i;
827 }
828 
829 static struct sk_buff *tsnep_build_skb(struct tsnep_rx *rx, struct page *page,
830 				       int length)
831 {
832 	struct sk_buff *skb;
833 
834 	skb = napi_build_skb(page_address(page), PAGE_SIZE);
835 	if (unlikely(!skb))
836 		return NULL;
837 
838 	/* update pointers within the skb to store the data */
839 	skb_reserve(skb, TSNEP_SKB_PAD + TSNEP_RX_INLINE_METADATA_SIZE);
840 	__skb_put(skb, length - TSNEP_RX_INLINE_METADATA_SIZE - ETH_FCS_LEN);
841 
842 	if (rx->adapter->hwtstamp_config.rx_filter == HWTSTAMP_FILTER_ALL) {
843 		struct skb_shared_hwtstamps *hwtstamps = skb_hwtstamps(skb);
844 		struct tsnep_rx_inline *rx_inline =
845 			(struct tsnep_rx_inline *)(page_address(page) +
846 						   TSNEP_SKB_PAD);
847 
848 		skb_shinfo(skb)->tx_flags |=
849 			SKBTX_HW_TSTAMP_NETDEV;
850 		memset(hwtstamps, 0, sizeof(*hwtstamps));
851 		hwtstamps->netdev_data = rx_inline;
852 	}
853 
854 	skb_record_rx_queue(skb, rx->queue_index);
855 	skb->protocol = eth_type_trans(skb, rx->adapter->netdev);
856 
857 	return skb;
858 }
859 
860 static int tsnep_rx_poll(struct tsnep_rx *rx, struct napi_struct *napi,
861 			 int budget)
862 {
863 	struct device *dmadev = rx->adapter->dmadev;
864 	int desc_available;
865 	int done = 0;
866 	enum dma_data_direction dma_dir;
867 	struct tsnep_rx_entry *entry;
868 	struct sk_buff *skb;
869 	int length;
870 
871 	desc_available = tsnep_rx_desc_available(rx);
872 	dma_dir = page_pool_get_dma_dir(rx->page_pool);
873 
874 	while (likely(done < budget) && (rx->read != rx->write)) {
875 		entry = &rx->entry[rx->read];
876 		if ((__le32_to_cpu(entry->desc_wb->properties) &
877 		     TSNEP_DESC_OWNER_COUNTER_MASK) !=
878 		    (entry->properties & TSNEP_DESC_OWNER_COUNTER_MASK))
879 			break;
880 		done++;
881 
882 		if (desc_available >= TSNEP_RING_RX_REFILL) {
883 			bool reuse = desc_available >= TSNEP_RING_RX_REUSE;
884 
885 			desc_available -= tsnep_rx_refill(rx, desc_available,
886 							  reuse);
887 			if (!entry->page) {
888 				/* buffer has been reused for refill to prevent
889 				 * empty RX ring, thus buffer cannot be used for
890 				 * RX processing
891 				 */
892 				rx->read = (rx->read + 1) % TSNEP_RING_SIZE;
893 				desc_available++;
894 
895 				rx->dropped++;
896 
897 				continue;
898 			}
899 		}
900 
901 		/* descriptor properties shall be read first, because valid data
902 		 * is signaled there
903 		 */
904 		dma_rmb();
905 
906 		prefetch(page_address(entry->page) + TSNEP_SKB_PAD);
907 		length = __le32_to_cpu(entry->desc_wb->properties) &
908 			 TSNEP_DESC_LENGTH_MASK;
909 		dma_sync_single_range_for_cpu(dmadev, entry->dma, TSNEP_SKB_PAD,
910 					      length, dma_dir);
911 
912 		rx->read = (rx->read + 1) % TSNEP_RING_SIZE;
913 		desc_available++;
914 
915 		skb = tsnep_build_skb(rx, entry->page, length);
916 		if (skb) {
917 			page_pool_release_page(rx->page_pool, entry->page);
918 
919 			rx->packets++;
920 			rx->bytes += length - TSNEP_RX_INLINE_METADATA_SIZE;
921 			if (skb->pkt_type == PACKET_MULTICAST)
922 				rx->multicast++;
923 
924 			napi_gro_receive(napi, skb);
925 		} else {
926 			page_pool_recycle_direct(rx->page_pool, entry->page);
927 
928 			rx->dropped++;
929 		}
930 		entry->page = NULL;
931 	}
932 
933 	if (desc_available)
934 		tsnep_rx_refill(rx, desc_available, false);
935 
936 	return done;
937 }
938 
939 static bool tsnep_rx_pending(struct tsnep_rx *rx)
940 {
941 	struct tsnep_rx_entry *entry;
942 
943 	if (rx->read != rx->write) {
944 		entry = &rx->entry[rx->read];
945 		if ((__le32_to_cpu(entry->desc_wb->properties) &
946 		     TSNEP_DESC_OWNER_COUNTER_MASK) ==
947 		    (entry->properties & TSNEP_DESC_OWNER_COUNTER_MASK))
948 			return true;
949 	}
950 
951 	return false;
952 }
953 
954 static int tsnep_rx_open(struct tsnep_adapter *adapter, void __iomem *addr,
955 			 int queue_index, struct tsnep_rx *rx)
956 {
957 	dma_addr_t dma;
958 	int retval;
959 
960 	memset(rx, 0, sizeof(*rx));
961 	rx->adapter = adapter;
962 	rx->addr = addr;
963 	rx->queue_index = queue_index;
964 
965 	retval = tsnep_rx_ring_init(rx);
966 	if (retval)
967 		return retval;
968 
969 	dma = rx->entry[0].desc_dma | TSNEP_RESET_OWNER_COUNTER;
970 	iowrite32(DMA_ADDR_LOW(dma), rx->addr + TSNEP_RX_DESC_ADDR_LOW);
971 	iowrite32(DMA_ADDR_HIGH(dma), rx->addr + TSNEP_RX_DESC_ADDR_HIGH);
972 	rx->owner_counter = 1;
973 	rx->increment_owner_counter = TSNEP_RING_SIZE - 1;
974 
975 	tsnep_rx_refill(rx, tsnep_rx_desc_available(rx), false);
976 
977 	return 0;
978 }
979 
980 static void tsnep_rx_close(struct tsnep_rx *rx)
981 {
982 	u32 val;
983 
984 	iowrite32(TSNEP_CONTROL_RX_DISABLE, rx->addr + TSNEP_CONTROL);
985 	readx_poll_timeout(ioread32, rx->addr + TSNEP_CONTROL, val,
986 			   ((val & TSNEP_CONTROL_RX_ENABLE) == 0), 10000,
987 			   1000000);
988 
989 	tsnep_rx_ring_cleanup(rx);
990 }
991 
992 static bool tsnep_pending(struct tsnep_queue *queue)
993 {
994 	if (queue->tx && tsnep_tx_pending(queue->tx))
995 		return true;
996 
997 	if (queue->rx && tsnep_rx_pending(queue->rx))
998 		return true;
999 
1000 	return false;
1001 }
1002 
1003 static int tsnep_poll(struct napi_struct *napi, int budget)
1004 {
1005 	struct tsnep_queue *queue = container_of(napi, struct tsnep_queue,
1006 						 napi);
1007 	bool complete = true;
1008 	int done = 0;
1009 
1010 	if (queue->tx)
1011 		complete = tsnep_tx_poll(queue->tx, budget);
1012 
1013 	if (queue->rx) {
1014 		done = tsnep_rx_poll(queue->rx, napi, budget);
1015 		if (done >= budget)
1016 			complete = false;
1017 	}
1018 
1019 	/* if all work not completed, return budget and keep polling */
1020 	if (!complete)
1021 		return budget;
1022 
1023 	if (likely(napi_complete_done(napi, done))) {
1024 		tsnep_enable_irq(queue->adapter, queue->irq_mask);
1025 
1026 		/* reschedule if work is already pending, prevent rotten packets
1027 		 * which are transmitted or received after polling but before
1028 		 * interrupt enable
1029 		 */
1030 		if (tsnep_pending(queue)) {
1031 			tsnep_disable_irq(queue->adapter, queue->irq_mask);
1032 			napi_schedule(napi);
1033 		}
1034 	}
1035 
1036 	return min(done, budget - 1);
1037 }
1038 
1039 static int tsnep_request_irq(struct tsnep_queue *queue, bool first)
1040 {
1041 	const char *name = netdev_name(queue->adapter->netdev);
1042 	irq_handler_t handler;
1043 	void *dev;
1044 	int retval;
1045 
1046 	if (first) {
1047 		sprintf(queue->name, "%s-mac", name);
1048 		handler = tsnep_irq;
1049 		dev = queue->adapter;
1050 	} else {
1051 		if (queue->tx && queue->rx)
1052 			sprintf(queue->name, "%s-txrx-%d", name,
1053 				queue->rx->queue_index);
1054 		else if (queue->tx)
1055 			sprintf(queue->name, "%s-tx-%d", name,
1056 				queue->tx->queue_index);
1057 		else
1058 			sprintf(queue->name, "%s-rx-%d", name,
1059 				queue->rx->queue_index);
1060 		handler = tsnep_irq_txrx;
1061 		dev = queue;
1062 	}
1063 
1064 	retval = request_irq(queue->irq, handler, 0, queue->name, dev);
1065 	if (retval) {
1066 		/* if name is empty, then interrupt won't be freed */
1067 		memset(queue->name, 0, sizeof(queue->name));
1068 	}
1069 
1070 	return retval;
1071 }
1072 
1073 static void tsnep_free_irq(struct tsnep_queue *queue, bool first)
1074 {
1075 	void *dev;
1076 
1077 	if (!strlen(queue->name))
1078 		return;
1079 
1080 	if (first)
1081 		dev = queue->adapter;
1082 	else
1083 		dev = queue;
1084 
1085 	free_irq(queue->irq, dev);
1086 	memset(queue->name, 0, sizeof(queue->name));
1087 }
1088 
1089 static int tsnep_netdev_open(struct net_device *netdev)
1090 {
1091 	struct tsnep_adapter *adapter = netdev_priv(netdev);
1092 	int i;
1093 	void __iomem *addr;
1094 	int tx_queue_index = 0;
1095 	int rx_queue_index = 0;
1096 	int retval;
1097 
1098 	for (i = 0; i < adapter->num_queues; i++) {
1099 		adapter->queue[i].adapter = adapter;
1100 		if (adapter->queue[i].tx) {
1101 			addr = adapter->addr + TSNEP_QUEUE(tx_queue_index);
1102 			retval = tsnep_tx_open(adapter, addr, tx_queue_index,
1103 					       adapter->queue[i].tx);
1104 			if (retval)
1105 				goto failed;
1106 			tx_queue_index++;
1107 		}
1108 		if (adapter->queue[i].rx) {
1109 			addr = adapter->addr + TSNEP_QUEUE(rx_queue_index);
1110 			retval = tsnep_rx_open(adapter, addr,
1111 					       rx_queue_index,
1112 					       adapter->queue[i].rx);
1113 			if (retval)
1114 				goto failed;
1115 			rx_queue_index++;
1116 		}
1117 
1118 		retval = tsnep_request_irq(&adapter->queue[i], i == 0);
1119 		if (retval) {
1120 			netif_err(adapter, drv, adapter->netdev,
1121 				  "can't get assigned irq %d.\n",
1122 				  adapter->queue[i].irq);
1123 			goto failed;
1124 		}
1125 	}
1126 
1127 	retval = netif_set_real_num_tx_queues(adapter->netdev,
1128 					      adapter->num_tx_queues);
1129 	if (retval)
1130 		goto failed;
1131 	retval = netif_set_real_num_rx_queues(adapter->netdev,
1132 					      adapter->num_rx_queues);
1133 	if (retval)
1134 		goto failed;
1135 
1136 	tsnep_enable_irq(adapter, ECM_INT_LINK);
1137 	retval = tsnep_phy_open(adapter);
1138 	if (retval)
1139 		goto phy_failed;
1140 
1141 	for (i = 0; i < adapter->num_queues; i++) {
1142 		netif_napi_add(adapter->netdev, &adapter->queue[i].napi,
1143 			       tsnep_poll);
1144 		napi_enable(&adapter->queue[i].napi);
1145 
1146 		tsnep_enable_irq(adapter, adapter->queue[i].irq_mask);
1147 	}
1148 
1149 	return 0;
1150 
1151 phy_failed:
1152 	tsnep_disable_irq(adapter, ECM_INT_LINK);
1153 	tsnep_phy_close(adapter);
1154 failed:
1155 	for (i = 0; i < adapter->num_queues; i++) {
1156 		tsnep_free_irq(&adapter->queue[i], i == 0);
1157 
1158 		if (adapter->queue[i].rx)
1159 			tsnep_rx_close(adapter->queue[i].rx);
1160 		if (adapter->queue[i].tx)
1161 			tsnep_tx_close(adapter->queue[i].tx);
1162 	}
1163 	return retval;
1164 }
1165 
1166 static int tsnep_netdev_close(struct net_device *netdev)
1167 {
1168 	struct tsnep_adapter *adapter = netdev_priv(netdev);
1169 	int i;
1170 
1171 	tsnep_disable_irq(adapter, ECM_INT_LINK);
1172 	tsnep_phy_close(adapter);
1173 
1174 	for (i = 0; i < adapter->num_queues; i++) {
1175 		tsnep_disable_irq(adapter, adapter->queue[i].irq_mask);
1176 
1177 		napi_disable(&adapter->queue[i].napi);
1178 		netif_napi_del(&adapter->queue[i].napi);
1179 
1180 		tsnep_free_irq(&adapter->queue[i], i == 0);
1181 
1182 		if (adapter->queue[i].rx)
1183 			tsnep_rx_close(adapter->queue[i].rx);
1184 		if (adapter->queue[i].tx)
1185 			tsnep_tx_close(adapter->queue[i].tx);
1186 	}
1187 
1188 	return 0;
1189 }
1190 
1191 static netdev_tx_t tsnep_netdev_xmit_frame(struct sk_buff *skb,
1192 					   struct net_device *netdev)
1193 {
1194 	struct tsnep_adapter *adapter = netdev_priv(netdev);
1195 	u16 queue_mapping = skb_get_queue_mapping(skb);
1196 
1197 	if (queue_mapping >= adapter->num_tx_queues)
1198 		queue_mapping = 0;
1199 
1200 	return tsnep_xmit_frame_ring(skb, &adapter->tx[queue_mapping]);
1201 }
1202 
1203 static int tsnep_netdev_ioctl(struct net_device *netdev, struct ifreq *ifr,
1204 			      int cmd)
1205 {
1206 	if (!netif_running(netdev))
1207 		return -EINVAL;
1208 	if (cmd == SIOCSHWTSTAMP || cmd == SIOCGHWTSTAMP)
1209 		return tsnep_ptp_ioctl(netdev, ifr, cmd);
1210 	return phy_mii_ioctl(netdev->phydev, ifr, cmd);
1211 }
1212 
1213 static void tsnep_netdev_set_multicast(struct net_device *netdev)
1214 {
1215 	struct tsnep_adapter *adapter = netdev_priv(netdev);
1216 
1217 	u16 rx_filter = 0;
1218 
1219 	/* configured MAC address and broadcasts are never filtered */
1220 	if (netdev->flags & IFF_PROMISC) {
1221 		rx_filter |= TSNEP_RX_FILTER_ACCEPT_ALL_MULTICASTS;
1222 		rx_filter |= TSNEP_RX_FILTER_ACCEPT_ALL_UNICASTS;
1223 	} else if (!netdev_mc_empty(netdev) || (netdev->flags & IFF_ALLMULTI)) {
1224 		rx_filter |= TSNEP_RX_FILTER_ACCEPT_ALL_MULTICASTS;
1225 	}
1226 	iowrite16(rx_filter, adapter->addr + TSNEP_RX_FILTER);
1227 }
1228 
1229 static void tsnep_netdev_get_stats64(struct net_device *netdev,
1230 				     struct rtnl_link_stats64 *stats)
1231 {
1232 	struct tsnep_adapter *adapter = netdev_priv(netdev);
1233 	u32 reg;
1234 	u32 val;
1235 	int i;
1236 
1237 	for (i = 0; i < adapter->num_tx_queues; i++) {
1238 		stats->tx_packets += adapter->tx[i].packets;
1239 		stats->tx_bytes += adapter->tx[i].bytes;
1240 		stats->tx_dropped += adapter->tx[i].dropped;
1241 	}
1242 	for (i = 0; i < adapter->num_rx_queues; i++) {
1243 		stats->rx_packets += adapter->rx[i].packets;
1244 		stats->rx_bytes += adapter->rx[i].bytes;
1245 		stats->rx_dropped += adapter->rx[i].dropped;
1246 		stats->multicast += adapter->rx[i].multicast;
1247 
1248 		reg = ioread32(adapter->addr + TSNEP_QUEUE(i) +
1249 			       TSNEP_RX_STATISTIC);
1250 		val = (reg & TSNEP_RX_STATISTIC_NO_DESC_MASK) >>
1251 		      TSNEP_RX_STATISTIC_NO_DESC_SHIFT;
1252 		stats->rx_dropped += val;
1253 		val = (reg & TSNEP_RX_STATISTIC_BUFFER_TOO_SMALL_MASK) >>
1254 		      TSNEP_RX_STATISTIC_BUFFER_TOO_SMALL_SHIFT;
1255 		stats->rx_dropped += val;
1256 		val = (reg & TSNEP_RX_STATISTIC_FIFO_OVERFLOW_MASK) >>
1257 		      TSNEP_RX_STATISTIC_FIFO_OVERFLOW_SHIFT;
1258 		stats->rx_errors += val;
1259 		stats->rx_fifo_errors += val;
1260 		val = (reg & TSNEP_RX_STATISTIC_INVALID_FRAME_MASK) >>
1261 		      TSNEP_RX_STATISTIC_INVALID_FRAME_SHIFT;
1262 		stats->rx_errors += val;
1263 		stats->rx_frame_errors += val;
1264 	}
1265 
1266 	reg = ioread32(adapter->addr + ECM_STAT);
1267 	val = (reg & ECM_STAT_RX_ERR_MASK) >> ECM_STAT_RX_ERR_SHIFT;
1268 	stats->rx_errors += val;
1269 	val = (reg & ECM_STAT_INV_FRM_MASK) >> ECM_STAT_INV_FRM_SHIFT;
1270 	stats->rx_errors += val;
1271 	stats->rx_crc_errors += val;
1272 	val = (reg & ECM_STAT_FWD_RX_ERR_MASK) >> ECM_STAT_FWD_RX_ERR_SHIFT;
1273 	stats->rx_errors += val;
1274 }
1275 
1276 static void tsnep_mac_set_address(struct tsnep_adapter *adapter, u8 *addr)
1277 {
1278 	iowrite32(*(u32 *)addr, adapter->addr + TSNEP_MAC_ADDRESS_LOW);
1279 	iowrite16(*(u16 *)(addr + sizeof(u32)),
1280 		  adapter->addr + TSNEP_MAC_ADDRESS_HIGH);
1281 
1282 	ether_addr_copy(adapter->mac_address, addr);
1283 	netif_info(adapter, drv, adapter->netdev, "MAC address set to %pM\n",
1284 		   addr);
1285 }
1286 
1287 static int tsnep_netdev_set_mac_address(struct net_device *netdev, void *addr)
1288 {
1289 	struct tsnep_adapter *adapter = netdev_priv(netdev);
1290 	struct sockaddr *sock_addr = addr;
1291 	int retval;
1292 
1293 	retval = eth_prepare_mac_addr_change(netdev, sock_addr);
1294 	if (retval)
1295 		return retval;
1296 	eth_hw_addr_set(netdev, sock_addr->sa_data);
1297 	tsnep_mac_set_address(adapter, sock_addr->sa_data);
1298 
1299 	return 0;
1300 }
1301 
1302 static int tsnep_netdev_set_features(struct net_device *netdev,
1303 				     netdev_features_t features)
1304 {
1305 	struct tsnep_adapter *adapter = netdev_priv(netdev);
1306 	netdev_features_t changed = netdev->features ^ features;
1307 	bool enable;
1308 	int retval = 0;
1309 
1310 	if (changed & NETIF_F_LOOPBACK) {
1311 		enable = !!(features & NETIF_F_LOOPBACK);
1312 		retval = tsnep_phy_loopback(adapter, enable);
1313 	}
1314 
1315 	return retval;
1316 }
1317 
1318 static ktime_t tsnep_netdev_get_tstamp(struct net_device *netdev,
1319 				       const struct skb_shared_hwtstamps *hwtstamps,
1320 				       bool cycles)
1321 {
1322 	struct tsnep_rx_inline *rx_inline = hwtstamps->netdev_data;
1323 	u64 timestamp;
1324 
1325 	if (cycles)
1326 		timestamp = __le64_to_cpu(rx_inline->counter);
1327 	else
1328 		timestamp = __le64_to_cpu(rx_inline->timestamp);
1329 
1330 	return ns_to_ktime(timestamp);
1331 }
1332 
1333 static const struct net_device_ops tsnep_netdev_ops = {
1334 	.ndo_open = tsnep_netdev_open,
1335 	.ndo_stop = tsnep_netdev_close,
1336 	.ndo_start_xmit = tsnep_netdev_xmit_frame,
1337 	.ndo_eth_ioctl = tsnep_netdev_ioctl,
1338 	.ndo_set_rx_mode = tsnep_netdev_set_multicast,
1339 	.ndo_get_stats64 = tsnep_netdev_get_stats64,
1340 	.ndo_set_mac_address = tsnep_netdev_set_mac_address,
1341 	.ndo_set_features = tsnep_netdev_set_features,
1342 	.ndo_get_tstamp = tsnep_netdev_get_tstamp,
1343 	.ndo_setup_tc = tsnep_tc_setup,
1344 };
1345 
1346 static int tsnep_mac_init(struct tsnep_adapter *adapter)
1347 {
1348 	int retval;
1349 
1350 	/* initialize RX filtering, at least configured MAC address and
1351 	 * broadcast are not filtered
1352 	 */
1353 	iowrite16(0, adapter->addr + TSNEP_RX_FILTER);
1354 
1355 	/* try to get MAC address in the following order:
1356 	 * - device tree
1357 	 * - valid MAC address already set
1358 	 * - MAC address register if valid
1359 	 * - random MAC address
1360 	 */
1361 	retval = of_get_mac_address(adapter->pdev->dev.of_node,
1362 				    adapter->mac_address);
1363 	if (retval == -EPROBE_DEFER)
1364 		return retval;
1365 	if (retval && !is_valid_ether_addr(adapter->mac_address)) {
1366 		*(u32 *)adapter->mac_address =
1367 			ioread32(adapter->addr + TSNEP_MAC_ADDRESS_LOW);
1368 		*(u16 *)(adapter->mac_address + sizeof(u32)) =
1369 			ioread16(adapter->addr + TSNEP_MAC_ADDRESS_HIGH);
1370 		if (!is_valid_ether_addr(adapter->mac_address))
1371 			eth_random_addr(adapter->mac_address);
1372 	}
1373 
1374 	tsnep_mac_set_address(adapter, adapter->mac_address);
1375 	eth_hw_addr_set(adapter->netdev, adapter->mac_address);
1376 
1377 	return 0;
1378 }
1379 
1380 static int tsnep_mdio_init(struct tsnep_adapter *adapter)
1381 {
1382 	struct device_node *np = adapter->pdev->dev.of_node;
1383 	int retval;
1384 
1385 	if (np) {
1386 		np = of_get_child_by_name(np, "mdio");
1387 		if (!np)
1388 			return 0;
1389 
1390 		adapter->suppress_preamble =
1391 			of_property_read_bool(np, "suppress-preamble");
1392 	}
1393 
1394 	adapter->mdiobus = devm_mdiobus_alloc(&adapter->pdev->dev);
1395 	if (!adapter->mdiobus) {
1396 		retval = -ENOMEM;
1397 
1398 		goto out;
1399 	}
1400 
1401 	adapter->mdiobus->priv = (void *)adapter;
1402 	adapter->mdiobus->parent = &adapter->pdev->dev;
1403 	adapter->mdiobus->read = tsnep_mdiobus_read;
1404 	adapter->mdiobus->write = tsnep_mdiobus_write;
1405 	adapter->mdiobus->name = TSNEP "-mdiobus";
1406 	snprintf(adapter->mdiobus->id, MII_BUS_ID_SIZE, "%s",
1407 		 adapter->pdev->name);
1408 
1409 	/* do not scan broadcast address */
1410 	adapter->mdiobus->phy_mask = 0x0000001;
1411 
1412 	retval = of_mdiobus_register(adapter->mdiobus, np);
1413 
1414 out:
1415 	of_node_put(np);
1416 
1417 	return retval;
1418 }
1419 
1420 static int tsnep_phy_init(struct tsnep_adapter *adapter)
1421 {
1422 	struct device_node *phy_node;
1423 	int retval;
1424 
1425 	retval = of_get_phy_mode(adapter->pdev->dev.of_node,
1426 				 &adapter->phy_mode);
1427 	if (retval)
1428 		adapter->phy_mode = PHY_INTERFACE_MODE_GMII;
1429 
1430 	phy_node = of_parse_phandle(adapter->pdev->dev.of_node, "phy-handle",
1431 				    0);
1432 	adapter->phydev = of_phy_find_device(phy_node);
1433 	of_node_put(phy_node);
1434 	if (!adapter->phydev && adapter->mdiobus)
1435 		adapter->phydev = phy_find_first(adapter->mdiobus);
1436 	if (!adapter->phydev)
1437 		return -EIO;
1438 
1439 	return 0;
1440 }
1441 
1442 static int tsnep_queue_init(struct tsnep_adapter *adapter, int queue_count)
1443 {
1444 	u32 irq_mask = ECM_INT_TX_0 | ECM_INT_RX_0;
1445 	char name[8];
1446 	int i;
1447 	int retval;
1448 
1449 	/* one TX/RX queue pair for netdev is mandatory */
1450 	if (platform_irq_count(adapter->pdev) == 1)
1451 		retval = platform_get_irq(adapter->pdev, 0);
1452 	else
1453 		retval = platform_get_irq_byname(adapter->pdev, "mac");
1454 	if (retval < 0)
1455 		return retval;
1456 	adapter->num_tx_queues = 1;
1457 	adapter->num_rx_queues = 1;
1458 	adapter->num_queues = 1;
1459 	adapter->queue[0].irq = retval;
1460 	adapter->queue[0].tx = &adapter->tx[0];
1461 	adapter->queue[0].rx = &adapter->rx[0];
1462 	adapter->queue[0].irq_mask = irq_mask;
1463 	adapter->queue[0].irq_delay_addr = adapter->addr + ECM_INT_DELAY;
1464 	retval = tsnep_set_irq_coalesce(&adapter->queue[0],
1465 					TSNEP_COALESCE_USECS_DEFAULT);
1466 	if (retval < 0)
1467 		return retval;
1468 
1469 	adapter->netdev->irq = adapter->queue[0].irq;
1470 
1471 	/* add additional TX/RX queue pairs only if dedicated interrupt is
1472 	 * available
1473 	 */
1474 	for (i = 1; i < queue_count; i++) {
1475 		sprintf(name, "txrx-%d", i);
1476 		retval = platform_get_irq_byname_optional(adapter->pdev, name);
1477 		if (retval < 0)
1478 			break;
1479 
1480 		adapter->num_tx_queues++;
1481 		adapter->num_rx_queues++;
1482 		adapter->num_queues++;
1483 		adapter->queue[i].irq = retval;
1484 		adapter->queue[i].tx = &adapter->tx[i];
1485 		adapter->queue[i].rx = &adapter->rx[i];
1486 		adapter->queue[i].irq_mask =
1487 			irq_mask << (ECM_INT_TXRX_SHIFT * i);
1488 		adapter->queue[i].irq_delay_addr =
1489 			adapter->addr + ECM_INT_DELAY + ECM_INT_DELAY_OFFSET * i;
1490 		retval = tsnep_set_irq_coalesce(&adapter->queue[i],
1491 						TSNEP_COALESCE_USECS_DEFAULT);
1492 		if (retval < 0)
1493 			return retval;
1494 	}
1495 
1496 	return 0;
1497 }
1498 
1499 static int tsnep_probe(struct platform_device *pdev)
1500 {
1501 	struct tsnep_adapter *adapter;
1502 	struct net_device *netdev;
1503 	struct resource *io;
1504 	u32 type;
1505 	int revision;
1506 	int version;
1507 	int queue_count;
1508 	int retval;
1509 
1510 	netdev = devm_alloc_etherdev_mqs(&pdev->dev,
1511 					 sizeof(struct tsnep_adapter),
1512 					 TSNEP_MAX_QUEUES, TSNEP_MAX_QUEUES);
1513 	if (!netdev)
1514 		return -ENODEV;
1515 	SET_NETDEV_DEV(netdev, &pdev->dev);
1516 	adapter = netdev_priv(netdev);
1517 	platform_set_drvdata(pdev, adapter);
1518 	adapter->pdev = pdev;
1519 	adapter->dmadev = &pdev->dev;
1520 	adapter->netdev = netdev;
1521 	adapter->msg_enable = NETIF_MSG_DRV | NETIF_MSG_PROBE |
1522 			      NETIF_MSG_LINK | NETIF_MSG_IFUP |
1523 			      NETIF_MSG_IFDOWN | NETIF_MSG_TX_QUEUED;
1524 
1525 	netdev->min_mtu = ETH_MIN_MTU;
1526 	netdev->max_mtu = TSNEP_MAX_FRAME_SIZE;
1527 
1528 	mutex_init(&adapter->gate_control_lock);
1529 	mutex_init(&adapter->rxnfc_lock);
1530 	INIT_LIST_HEAD(&adapter->rxnfc_rules);
1531 
1532 	io = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1533 	adapter->addr = devm_ioremap_resource(&pdev->dev, io);
1534 	if (IS_ERR(adapter->addr))
1535 		return PTR_ERR(adapter->addr);
1536 	netdev->mem_start = io->start;
1537 	netdev->mem_end = io->end;
1538 
1539 	type = ioread32(adapter->addr + ECM_TYPE);
1540 	revision = (type & ECM_REVISION_MASK) >> ECM_REVISION_SHIFT;
1541 	version = (type & ECM_VERSION_MASK) >> ECM_VERSION_SHIFT;
1542 	queue_count = (type & ECM_QUEUE_COUNT_MASK) >> ECM_QUEUE_COUNT_SHIFT;
1543 	adapter->gate_control = type & ECM_GATE_CONTROL;
1544 	adapter->rxnfc_max = TSNEP_RX_ASSIGN_ETHER_TYPE_COUNT;
1545 
1546 	tsnep_disable_irq(adapter, ECM_INT_ALL);
1547 
1548 	retval = tsnep_queue_init(adapter, queue_count);
1549 	if (retval)
1550 		return retval;
1551 
1552 	retval = dma_set_mask_and_coherent(&adapter->pdev->dev,
1553 					   DMA_BIT_MASK(64));
1554 	if (retval) {
1555 		dev_err(&adapter->pdev->dev, "no usable DMA configuration.\n");
1556 		return retval;
1557 	}
1558 
1559 	retval = tsnep_mac_init(adapter);
1560 	if (retval)
1561 		return retval;
1562 
1563 	retval = tsnep_mdio_init(adapter);
1564 	if (retval)
1565 		goto mdio_init_failed;
1566 
1567 	retval = tsnep_phy_init(adapter);
1568 	if (retval)
1569 		goto phy_init_failed;
1570 
1571 	retval = tsnep_ptp_init(adapter);
1572 	if (retval)
1573 		goto ptp_init_failed;
1574 
1575 	retval = tsnep_tc_init(adapter);
1576 	if (retval)
1577 		goto tc_init_failed;
1578 
1579 	retval = tsnep_rxnfc_init(adapter);
1580 	if (retval)
1581 		goto rxnfc_init_failed;
1582 
1583 	netdev->netdev_ops = &tsnep_netdev_ops;
1584 	netdev->ethtool_ops = &tsnep_ethtool_ops;
1585 	netdev->features = NETIF_F_SG;
1586 	netdev->hw_features = netdev->features | NETIF_F_LOOPBACK;
1587 
1588 	/* carrier off reporting is important to ethtool even BEFORE open */
1589 	netif_carrier_off(netdev);
1590 
1591 	retval = register_netdev(netdev);
1592 	if (retval)
1593 		goto register_failed;
1594 
1595 	dev_info(&adapter->pdev->dev, "device version %d.%02d\n", version,
1596 		 revision);
1597 	if (adapter->gate_control)
1598 		dev_info(&adapter->pdev->dev, "gate control detected\n");
1599 
1600 	return 0;
1601 
1602 register_failed:
1603 	tsnep_rxnfc_cleanup(adapter);
1604 rxnfc_init_failed:
1605 	tsnep_tc_cleanup(adapter);
1606 tc_init_failed:
1607 	tsnep_ptp_cleanup(adapter);
1608 ptp_init_failed:
1609 phy_init_failed:
1610 	if (adapter->mdiobus)
1611 		mdiobus_unregister(adapter->mdiobus);
1612 mdio_init_failed:
1613 	return retval;
1614 }
1615 
1616 static int tsnep_remove(struct platform_device *pdev)
1617 {
1618 	struct tsnep_adapter *adapter = platform_get_drvdata(pdev);
1619 
1620 	unregister_netdev(adapter->netdev);
1621 
1622 	tsnep_rxnfc_cleanup(adapter);
1623 
1624 	tsnep_tc_cleanup(adapter);
1625 
1626 	tsnep_ptp_cleanup(adapter);
1627 
1628 	if (adapter->mdiobus)
1629 		mdiobus_unregister(adapter->mdiobus);
1630 
1631 	tsnep_disable_irq(adapter, ECM_INT_ALL);
1632 
1633 	return 0;
1634 }
1635 
1636 static const struct of_device_id tsnep_of_match[] = {
1637 	{ .compatible = "engleder,tsnep", },
1638 { },
1639 };
1640 MODULE_DEVICE_TABLE(of, tsnep_of_match);
1641 
1642 static struct platform_driver tsnep_driver = {
1643 	.driver = {
1644 		.name = TSNEP,
1645 		.of_match_table = tsnep_of_match,
1646 	},
1647 	.probe = tsnep_probe,
1648 	.remove = tsnep_remove,
1649 };
1650 module_platform_driver(tsnep_driver);
1651 
1652 MODULE_AUTHOR("Gerhard Engleder <gerhard@engleder-embedded.com>");
1653 MODULE_DESCRIPTION("TSN endpoint Ethernet MAC driver");
1654 MODULE_LICENSE("GPL");
1655