xref: /linux/drivers/net/ethernet/apm/xgene-v2/main.c (revision 52338415)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Applied Micro X-Gene SoC Ethernet v2 Driver
4  *
5  * Copyright (c) 2017, Applied Micro Circuits Corporation
6  * Author(s): Iyappan Subramanian <isubramanian@apm.com>
7  *	      Keyur Chudgar <kchudgar@apm.com>
8  */
9 
10 #include "main.h"
11 
12 static const struct acpi_device_id xge_acpi_match[];
13 
14 static int xge_get_resources(struct xge_pdata *pdata)
15 {
16 	struct platform_device *pdev;
17 	struct net_device *ndev;
18 	int phy_mode, ret = 0;
19 	struct resource *res;
20 	struct device *dev;
21 
22 	pdev = pdata->pdev;
23 	dev = &pdev->dev;
24 	ndev = pdata->ndev;
25 
26 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
27 	if (!res) {
28 		dev_err(dev, "Resource enet_csr not defined\n");
29 		return -ENODEV;
30 	}
31 
32 	pdata->resources.base_addr = devm_ioremap(dev, res->start,
33 						  resource_size(res));
34 	if (!pdata->resources.base_addr) {
35 		dev_err(dev, "Unable to retrieve ENET Port CSR region\n");
36 		return -ENOMEM;
37 	}
38 
39 	if (!device_get_mac_address(dev, ndev->dev_addr, ETH_ALEN))
40 		eth_hw_addr_random(ndev);
41 
42 	memcpy(ndev->perm_addr, ndev->dev_addr, ndev->addr_len);
43 
44 	phy_mode = device_get_phy_mode(dev);
45 	if (phy_mode < 0) {
46 		dev_err(dev, "Unable to get phy-connection-type\n");
47 		return phy_mode;
48 	}
49 	pdata->resources.phy_mode = phy_mode;
50 
51 	if (pdata->resources.phy_mode != PHY_INTERFACE_MODE_RGMII) {
52 		dev_err(dev, "Incorrect phy-connection-type specified\n");
53 		return -ENODEV;
54 	}
55 
56 	ret = platform_get_irq(pdev, 0);
57 	if (ret < 0)
58 		return ret;
59 	pdata->resources.irq = ret;
60 
61 	return 0;
62 }
63 
64 static int xge_refill_buffers(struct net_device *ndev, u32 nbuf)
65 {
66 	struct xge_pdata *pdata = netdev_priv(ndev);
67 	struct xge_desc_ring *ring = pdata->rx_ring;
68 	const u8 slots = XGENE_ENET_NUM_DESC - 1;
69 	struct device *dev = &pdata->pdev->dev;
70 	struct xge_raw_desc *raw_desc;
71 	u64 addr_lo, addr_hi;
72 	u8 tail = ring->tail;
73 	struct sk_buff *skb;
74 	dma_addr_t dma_addr;
75 	u16 len;
76 	int i;
77 
78 	for (i = 0; i < nbuf; i++) {
79 		raw_desc = &ring->raw_desc[tail];
80 
81 		len = XGENE_ENET_STD_MTU;
82 		skb = netdev_alloc_skb(ndev, len);
83 		if (unlikely(!skb))
84 			return -ENOMEM;
85 
86 		dma_addr = dma_map_single(dev, skb->data, len, DMA_FROM_DEVICE);
87 		if (dma_mapping_error(dev, dma_addr)) {
88 			netdev_err(ndev, "DMA mapping error\n");
89 			dev_kfree_skb_any(skb);
90 			return -EINVAL;
91 		}
92 
93 		ring->pkt_info[tail].skb = skb;
94 		ring->pkt_info[tail].dma_addr = dma_addr;
95 
96 		addr_hi = GET_BITS(NEXT_DESC_ADDRH, le64_to_cpu(raw_desc->m1));
97 		addr_lo = GET_BITS(NEXT_DESC_ADDRL, le64_to_cpu(raw_desc->m1));
98 		raw_desc->m1 = cpu_to_le64(SET_BITS(NEXT_DESC_ADDRL, addr_lo) |
99 					   SET_BITS(NEXT_DESC_ADDRH, addr_hi) |
100 					   SET_BITS(PKT_ADDRH,
101 						    upper_32_bits(dma_addr)));
102 
103 		dma_wmb();
104 		raw_desc->m0 = cpu_to_le64(SET_BITS(PKT_ADDRL, dma_addr) |
105 					   SET_BITS(E, 1));
106 		tail = (tail + 1) & slots;
107 	}
108 
109 	ring->tail = tail;
110 
111 	return 0;
112 }
113 
114 static int xge_init_hw(struct net_device *ndev)
115 {
116 	struct xge_pdata *pdata = netdev_priv(ndev);
117 	int ret;
118 
119 	ret = xge_port_reset(ndev);
120 	if (ret)
121 		return ret;
122 
123 	xge_port_init(ndev);
124 	pdata->nbufs = NUM_BUFS;
125 
126 	return 0;
127 }
128 
129 static irqreturn_t xge_irq(const int irq, void *data)
130 {
131 	struct xge_pdata *pdata = data;
132 
133 	if (napi_schedule_prep(&pdata->napi)) {
134 		xge_intr_disable(pdata);
135 		__napi_schedule(&pdata->napi);
136 	}
137 
138 	return IRQ_HANDLED;
139 }
140 
141 static int xge_request_irq(struct net_device *ndev)
142 {
143 	struct xge_pdata *pdata = netdev_priv(ndev);
144 	int ret;
145 
146 	snprintf(pdata->irq_name, IRQ_ID_SIZE, "%s", ndev->name);
147 
148 	ret = request_irq(pdata->resources.irq, xge_irq, 0, pdata->irq_name,
149 			  pdata);
150 	if (ret)
151 		netdev_err(ndev, "Failed to request irq %s\n", pdata->irq_name);
152 
153 	return ret;
154 }
155 
156 static void xge_free_irq(struct net_device *ndev)
157 {
158 	struct xge_pdata *pdata = netdev_priv(ndev);
159 
160 	free_irq(pdata->resources.irq, pdata);
161 }
162 
163 static bool is_tx_slot_available(struct xge_raw_desc *raw_desc)
164 {
165 	if (GET_BITS(E, le64_to_cpu(raw_desc->m0)) &&
166 	    (GET_BITS(PKT_SIZE, le64_to_cpu(raw_desc->m0)) == SLOT_EMPTY))
167 		return true;
168 
169 	return false;
170 }
171 
172 static netdev_tx_t xge_start_xmit(struct sk_buff *skb, struct net_device *ndev)
173 {
174 	struct xge_pdata *pdata = netdev_priv(ndev);
175 	struct device *dev = &pdata->pdev->dev;
176 	struct xge_desc_ring *tx_ring;
177 	struct xge_raw_desc *raw_desc;
178 	static dma_addr_t dma_addr;
179 	u64 addr_lo, addr_hi;
180 	void *pkt_buf;
181 	u8 tail;
182 	u16 len;
183 
184 	tx_ring = pdata->tx_ring;
185 	tail = tx_ring->tail;
186 	len = skb_headlen(skb);
187 	raw_desc = &tx_ring->raw_desc[tail];
188 
189 	if (!is_tx_slot_available(raw_desc)) {
190 		netif_stop_queue(ndev);
191 		return NETDEV_TX_BUSY;
192 	}
193 
194 	/* Packet buffers should be 64B aligned */
195 	pkt_buf = dma_alloc_coherent(dev, XGENE_ENET_STD_MTU, &dma_addr,
196 				     GFP_ATOMIC);
197 	if (unlikely(!pkt_buf)) {
198 		dev_kfree_skb_any(skb);
199 		return NETDEV_TX_OK;
200 	}
201 	memcpy(pkt_buf, skb->data, len);
202 
203 	addr_hi = GET_BITS(NEXT_DESC_ADDRH, le64_to_cpu(raw_desc->m1));
204 	addr_lo = GET_BITS(NEXT_DESC_ADDRL, le64_to_cpu(raw_desc->m1));
205 	raw_desc->m1 = cpu_to_le64(SET_BITS(NEXT_DESC_ADDRL, addr_lo) |
206 				   SET_BITS(NEXT_DESC_ADDRH, addr_hi) |
207 				   SET_BITS(PKT_ADDRH,
208 					    upper_32_bits(dma_addr)));
209 
210 	tx_ring->pkt_info[tail].skb = skb;
211 	tx_ring->pkt_info[tail].dma_addr = dma_addr;
212 	tx_ring->pkt_info[tail].pkt_buf = pkt_buf;
213 
214 	dma_wmb();
215 
216 	raw_desc->m0 = cpu_to_le64(SET_BITS(PKT_ADDRL, dma_addr) |
217 				   SET_BITS(PKT_SIZE, len) |
218 				   SET_BITS(E, 0));
219 	skb_tx_timestamp(skb);
220 	xge_wr_csr(pdata, DMATXCTRL, 1);
221 
222 	tx_ring->tail = (tail + 1) & (XGENE_ENET_NUM_DESC - 1);
223 
224 	return NETDEV_TX_OK;
225 }
226 
227 static bool is_tx_hw_done(struct xge_raw_desc *raw_desc)
228 {
229 	if (GET_BITS(E, le64_to_cpu(raw_desc->m0)) &&
230 	    !GET_BITS(PKT_SIZE, le64_to_cpu(raw_desc->m0)))
231 		return true;
232 
233 	return false;
234 }
235 
236 static void xge_txc_poll(struct net_device *ndev)
237 {
238 	struct xge_pdata *pdata = netdev_priv(ndev);
239 	struct device *dev = &pdata->pdev->dev;
240 	struct xge_desc_ring *tx_ring;
241 	struct xge_raw_desc *raw_desc;
242 	dma_addr_t dma_addr;
243 	struct sk_buff *skb;
244 	void *pkt_buf;
245 	u32 data;
246 	u8 head;
247 
248 	tx_ring = pdata->tx_ring;
249 	head = tx_ring->head;
250 
251 	data = xge_rd_csr(pdata, DMATXSTATUS);
252 	if (!GET_BITS(TXPKTCOUNT, data))
253 		return;
254 
255 	while (1) {
256 		raw_desc = &tx_ring->raw_desc[head];
257 
258 		if (!is_tx_hw_done(raw_desc))
259 			break;
260 
261 		dma_rmb();
262 
263 		skb = tx_ring->pkt_info[head].skb;
264 		dma_addr = tx_ring->pkt_info[head].dma_addr;
265 		pkt_buf = tx_ring->pkt_info[head].pkt_buf;
266 		pdata->stats.tx_packets++;
267 		pdata->stats.tx_bytes += skb->len;
268 		dma_free_coherent(dev, XGENE_ENET_STD_MTU, pkt_buf, dma_addr);
269 		dev_kfree_skb_any(skb);
270 
271 		/* clear pktstart address and pktsize */
272 		raw_desc->m0 = cpu_to_le64(SET_BITS(E, 1) |
273 					   SET_BITS(PKT_SIZE, SLOT_EMPTY));
274 		xge_wr_csr(pdata, DMATXSTATUS, 1);
275 
276 		head = (head + 1) & (XGENE_ENET_NUM_DESC - 1);
277 	}
278 
279 	if (netif_queue_stopped(ndev))
280 		netif_wake_queue(ndev);
281 
282 	tx_ring->head = head;
283 }
284 
285 static int xge_rx_poll(struct net_device *ndev, unsigned int budget)
286 {
287 	struct xge_pdata *pdata = netdev_priv(ndev);
288 	struct device *dev = &pdata->pdev->dev;
289 	struct xge_desc_ring *rx_ring;
290 	struct xge_raw_desc *raw_desc;
291 	struct sk_buff *skb;
292 	dma_addr_t dma_addr;
293 	int processed = 0;
294 	u8 head, rx_error;
295 	int i, ret;
296 	u32 data;
297 	u16 len;
298 
299 	rx_ring = pdata->rx_ring;
300 	head = rx_ring->head;
301 
302 	data = xge_rd_csr(pdata, DMARXSTATUS);
303 	if (!GET_BITS(RXPKTCOUNT, data))
304 		return 0;
305 
306 	for (i = 0; i < budget; i++) {
307 		raw_desc = &rx_ring->raw_desc[head];
308 
309 		if (GET_BITS(E, le64_to_cpu(raw_desc->m0)))
310 			break;
311 
312 		dma_rmb();
313 
314 		skb = rx_ring->pkt_info[head].skb;
315 		rx_ring->pkt_info[head].skb = NULL;
316 		dma_addr = rx_ring->pkt_info[head].dma_addr;
317 		len = GET_BITS(PKT_SIZE, le64_to_cpu(raw_desc->m0));
318 		dma_unmap_single(dev, dma_addr, XGENE_ENET_STD_MTU,
319 				 DMA_FROM_DEVICE);
320 
321 		rx_error = GET_BITS(D, le64_to_cpu(raw_desc->m2));
322 		if (unlikely(rx_error)) {
323 			pdata->stats.rx_errors++;
324 			dev_kfree_skb_any(skb);
325 			goto out;
326 		}
327 
328 		skb_put(skb, len);
329 		skb->protocol = eth_type_trans(skb, ndev);
330 
331 		pdata->stats.rx_packets++;
332 		pdata->stats.rx_bytes += len;
333 		napi_gro_receive(&pdata->napi, skb);
334 out:
335 		ret = xge_refill_buffers(ndev, 1);
336 		xge_wr_csr(pdata, DMARXSTATUS, 1);
337 		xge_wr_csr(pdata, DMARXCTRL, 1);
338 
339 		if (ret)
340 			break;
341 
342 		head = (head + 1) & (XGENE_ENET_NUM_DESC - 1);
343 		processed++;
344 	}
345 
346 	rx_ring->head = head;
347 
348 	return processed;
349 }
350 
351 static void xge_delete_desc_ring(struct net_device *ndev,
352 				 struct xge_desc_ring *ring)
353 {
354 	struct xge_pdata *pdata = netdev_priv(ndev);
355 	struct device *dev = &pdata->pdev->dev;
356 	u16 size;
357 
358 	if (!ring)
359 		return;
360 
361 	size = XGENE_ENET_DESC_SIZE * XGENE_ENET_NUM_DESC;
362 	if (ring->desc_addr)
363 		dma_free_coherent(dev, size, ring->desc_addr, ring->dma_addr);
364 
365 	kfree(ring->pkt_info);
366 	kfree(ring);
367 }
368 
369 static void xge_free_buffers(struct net_device *ndev)
370 {
371 	struct xge_pdata *pdata = netdev_priv(ndev);
372 	struct xge_desc_ring *ring = pdata->rx_ring;
373 	struct device *dev = &pdata->pdev->dev;
374 	struct sk_buff *skb;
375 	dma_addr_t dma_addr;
376 	int i;
377 
378 	for (i = 0; i < XGENE_ENET_NUM_DESC; i++) {
379 		skb = ring->pkt_info[i].skb;
380 		dma_addr = ring->pkt_info[i].dma_addr;
381 
382 		if (!skb)
383 			continue;
384 
385 		dma_unmap_single(dev, dma_addr, XGENE_ENET_STD_MTU,
386 				 DMA_FROM_DEVICE);
387 		dev_kfree_skb_any(skb);
388 	}
389 }
390 
391 static void xge_delete_desc_rings(struct net_device *ndev)
392 {
393 	struct xge_pdata *pdata = netdev_priv(ndev);
394 
395 	xge_txc_poll(ndev);
396 	xge_delete_desc_ring(ndev, pdata->tx_ring);
397 
398 	xge_rx_poll(ndev, 64);
399 	xge_free_buffers(ndev);
400 	xge_delete_desc_ring(ndev, pdata->rx_ring);
401 }
402 
403 static struct xge_desc_ring *xge_create_desc_ring(struct net_device *ndev)
404 {
405 	struct xge_pdata *pdata = netdev_priv(ndev);
406 	struct device *dev = &pdata->pdev->dev;
407 	struct xge_desc_ring *ring;
408 	u16 size;
409 
410 	ring = kzalloc(sizeof(*ring), GFP_KERNEL);
411 	if (!ring)
412 		return NULL;
413 
414 	ring->ndev = ndev;
415 
416 	size = XGENE_ENET_DESC_SIZE * XGENE_ENET_NUM_DESC;
417 	ring->desc_addr = dma_alloc_coherent(dev, size, &ring->dma_addr,
418 					     GFP_KERNEL);
419 	if (!ring->desc_addr)
420 		goto err;
421 
422 	ring->pkt_info = kcalloc(XGENE_ENET_NUM_DESC, sizeof(*ring->pkt_info),
423 				 GFP_KERNEL);
424 	if (!ring->pkt_info)
425 		goto err;
426 
427 	xge_setup_desc(ring);
428 
429 	return ring;
430 
431 err:
432 	xge_delete_desc_ring(ndev, ring);
433 
434 	return NULL;
435 }
436 
437 static int xge_create_desc_rings(struct net_device *ndev)
438 {
439 	struct xge_pdata *pdata = netdev_priv(ndev);
440 	struct xge_desc_ring *ring;
441 	int ret;
442 
443 	/* create tx ring */
444 	ring = xge_create_desc_ring(ndev);
445 	if (!ring)
446 		goto err;
447 
448 	pdata->tx_ring = ring;
449 	xge_update_tx_desc_addr(pdata);
450 
451 	/* create rx ring */
452 	ring = xge_create_desc_ring(ndev);
453 	if (!ring)
454 		goto err;
455 
456 	pdata->rx_ring = ring;
457 	xge_update_rx_desc_addr(pdata);
458 
459 	ret = xge_refill_buffers(ndev, XGENE_ENET_NUM_DESC);
460 	if (ret)
461 		goto err;
462 
463 	return 0;
464 err:
465 	xge_delete_desc_rings(ndev);
466 
467 	return -ENOMEM;
468 }
469 
470 static int xge_open(struct net_device *ndev)
471 {
472 	struct xge_pdata *pdata = netdev_priv(ndev);
473 	int ret;
474 
475 	ret = xge_create_desc_rings(ndev);
476 	if (ret)
477 		return ret;
478 
479 	napi_enable(&pdata->napi);
480 	ret = xge_request_irq(ndev);
481 	if (ret)
482 		return ret;
483 
484 	xge_intr_enable(pdata);
485 	xge_wr_csr(pdata, DMARXCTRL, 1);
486 
487 	phy_start(ndev->phydev);
488 	xge_mac_enable(pdata);
489 	netif_start_queue(ndev);
490 
491 	return 0;
492 }
493 
494 static int xge_close(struct net_device *ndev)
495 {
496 	struct xge_pdata *pdata = netdev_priv(ndev);
497 
498 	netif_stop_queue(ndev);
499 	xge_mac_disable(pdata);
500 	phy_stop(ndev->phydev);
501 
502 	xge_intr_disable(pdata);
503 	xge_free_irq(ndev);
504 	napi_disable(&pdata->napi);
505 	xge_delete_desc_rings(ndev);
506 
507 	return 0;
508 }
509 
510 static int xge_napi(struct napi_struct *napi, const int budget)
511 {
512 	struct net_device *ndev = napi->dev;
513 	struct xge_pdata *pdata;
514 	int processed;
515 
516 	pdata = netdev_priv(ndev);
517 
518 	xge_txc_poll(ndev);
519 	processed = xge_rx_poll(ndev, budget);
520 
521 	if (processed < budget) {
522 		napi_complete_done(napi, processed);
523 		xge_intr_enable(pdata);
524 	}
525 
526 	return processed;
527 }
528 
529 static int xge_set_mac_addr(struct net_device *ndev, void *addr)
530 {
531 	struct xge_pdata *pdata = netdev_priv(ndev);
532 	int ret;
533 
534 	ret = eth_mac_addr(ndev, addr);
535 	if (ret)
536 		return ret;
537 
538 	xge_mac_set_station_addr(pdata);
539 
540 	return 0;
541 }
542 
543 static bool is_tx_pending(struct xge_raw_desc *raw_desc)
544 {
545 	if (!GET_BITS(E, le64_to_cpu(raw_desc->m0)))
546 		return true;
547 
548 	return false;
549 }
550 
551 static void xge_free_pending_skb(struct net_device *ndev)
552 {
553 	struct xge_pdata *pdata = netdev_priv(ndev);
554 	struct device *dev = &pdata->pdev->dev;
555 	struct xge_desc_ring *tx_ring;
556 	struct xge_raw_desc *raw_desc;
557 	dma_addr_t dma_addr;
558 	struct sk_buff *skb;
559 	void *pkt_buf;
560 	int i;
561 
562 	tx_ring = pdata->tx_ring;
563 
564 	for (i = 0; i < XGENE_ENET_NUM_DESC; i++) {
565 		raw_desc = &tx_ring->raw_desc[i];
566 
567 		if (!is_tx_pending(raw_desc))
568 			continue;
569 
570 		skb = tx_ring->pkt_info[i].skb;
571 		dma_addr = tx_ring->pkt_info[i].dma_addr;
572 		pkt_buf = tx_ring->pkt_info[i].pkt_buf;
573 		dma_free_coherent(dev, XGENE_ENET_STD_MTU, pkt_buf, dma_addr);
574 		dev_kfree_skb_any(skb);
575 	}
576 }
577 
578 static void xge_timeout(struct net_device *ndev)
579 {
580 	struct xge_pdata *pdata = netdev_priv(ndev);
581 
582 	rtnl_lock();
583 
584 	if (!netif_running(ndev))
585 		goto out;
586 
587 	netif_stop_queue(ndev);
588 	xge_intr_disable(pdata);
589 	napi_disable(&pdata->napi);
590 
591 	xge_wr_csr(pdata, DMATXCTRL, 0);
592 	xge_txc_poll(ndev);
593 	xge_free_pending_skb(ndev);
594 	xge_wr_csr(pdata, DMATXSTATUS, ~0U);
595 
596 	xge_setup_desc(pdata->tx_ring);
597 	xge_update_tx_desc_addr(pdata);
598 	xge_mac_init(pdata);
599 
600 	napi_enable(&pdata->napi);
601 	xge_intr_enable(pdata);
602 	xge_mac_enable(pdata);
603 	netif_start_queue(ndev);
604 
605 out:
606 	rtnl_unlock();
607 }
608 
609 static void xge_get_stats64(struct net_device *ndev,
610 			    struct rtnl_link_stats64 *storage)
611 {
612 	struct xge_pdata *pdata = netdev_priv(ndev);
613 	struct xge_stats *stats = &pdata->stats;
614 
615 	storage->tx_packets += stats->tx_packets;
616 	storage->tx_bytes += stats->tx_bytes;
617 
618 	storage->rx_packets += stats->rx_packets;
619 	storage->rx_bytes += stats->rx_bytes;
620 	storage->rx_errors += stats->rx_errors;
621 }
622 
623 static const struct net_device_ops xgene_ndev_ops = {
624 	.ndo_open = xge_open,
625 	.ndo_stop = xge_close,
626 	.ndo_start_xmit = xge_start_xmit,
627 	.ndo_set_mac_address = xge_set_mac_addr,
628 	.ndo_tx_timeout = xge_timeout,
629 	.ndo_get_stats64 = xge_get_stats64,
630 };
631 
632 static int xge_probe(struct platform_device *pdev)
633 {
634 	struct device *dev = &pdev->dev;
635 	struct net_device *ndev;
636 	struct xge_pdata *pdata;
637 	int ret;
638 
639 	ndev = alloc_etherdev(sizeof(*pdata));
640 	if (!ndev)
641 		return -ENOMEM;
642 
643 	pdata = netdev_priv(ndev);
644 
645 	pdata->pdev = pdev;
646 	pdata->ndev = ndev;
647 	SET_NETDEV_DEV(ndev, dev);
648 	platform_set_drvdata(pdev, pdata);
649 	ndev->netdev_ops = &xgene_ndev_ops;
650 
651 	ndev->features |= NETIF_F_GSO |
652 			  NETIF_F_GRO;
653 
654 	ret = xge_get_resources(pdata);
655 	if (ret)
656 		goto err;
657 
658 	ndev->hw_features = ndev->features;
659 	xge_set_ethtool_ops(ndev);
660 
661 	ret = dma_coerce_mask_and_coherent(dev, DMA_BIT_MASK(64));
662 	if (ret) {
663 		netdev_err(ndev, "No usable DMA configuration\n");
664 		goto err;
665 	}
666 
667 	ret = xge_init_hw(ndev);
668 	if (ret)
669 		goto err;
670 
671 	ret = xge_mdio_config(ndev);
672 	if (ret)
673 		goto err;
674 
675 	netif_napi_add(ndev, &pdata->napi, xge_napi, NAPI_POLL_WEIGHT);
676 
677 	ret = register_netdev(ndev);
678 	if (ret) {
679 		netdev_err(ndev, "Failed to register netdev\n");
680 		goto err;
681 	}
682 
683 	return 0;
684 
685 err:
686 	free_netdev(ndev);
687 
688 	return ret;
689 }
690 
691 static int xge_remove(struct platform_device *pdev)
692 {
693 	struct xge_pdata *pdata;
694 	struct net_device *ndev;
695 
696 	pdata = platform_get_drvdata(pdev);
697 	ndev = pdata->ndev;
698 
699 	rtnl_lock();
700 	if (netif_running(ndev))
701 		dev_close(ndev);
702 	rtnl_unlock();
703 
704 	xge_mdio_remove(ndev);
705 	unregister_netdev(ndev);
706 	free_netdev(ndev);
707 
708 	return 0;
709 }
710 
711 static void xge_shutdown(struct platform_device *pdev)
712 {
713 	struct xge_pdata *pdata;
714 
715 	pdata = platform_get_drvdata(pdev);
716 	if (!pdata)
717 		return;
718 
719 	if (!pdata->ndev)
720 		return;
721 
722 	xge_remove(pdev);
723 }
724 
725 static const struct acpi_device_id xge_acpi_match[] = {
726 	{ "APMC0D80" },
727 	{ }
728 };
729 MODULE_DEVICE_TABLE(acpi, xge_acpi_match);
730 
731 static struct platform_driver xge_driver = {
732 	.driver = {
733 		   .name = "xgene-enet-v2",
734 		   .acpi_match_table = ACPI_PTR(xge_acpi_match),
735 	},
736 	.probe = xge_probe,
737 	.remove = xge_remove,
738 	.shutdown = xge_shutdown,
739 };
740 module_platform_driver(xge_driver);
741 
742 MODULE_DESCRIPTION("APM X-Gene SoC Ethernet v2 driver");
743 MODULE_AUTHOR("Iyappan Subramanian <isubramanian@apm.com>");
744 MODULE_VERSION(XGENE_ENET_V2_VERSION);
745 MODULE_LICENSE("GPL");
746