xref: /linux/drivers/net/ethernet/ethoc.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * linux/drivers/net/ethernet/ethoc.c
4  *
5  * Copyright (C) 2007-2008 Avionic Design Development GmbH
6  * Copyright (C) 2008-2009 Avionic Design GmbH
7  *
8  * Written by Thierry Reding <thierry.reding@avionic-design.de>
9  */
10 
11 #include <linux/dma-mapping.h>
12 #include <linux/etherdevice.h>
13 #include <linux/clk.h>
14 #include <linux/crc32.h>
15 #include <linux/interrupt.h>
16 #include <linux/io.h>
17 #include <linux/mii.h>
18 #include <linux/phy.h>
19 #include <linux/platform_device.h>
20 #include <linux/sched.h>
21 #include <linux/slab.h>
22 #include <linux/of.h>
23 #include <linux/of_net.h>
24 #include <linux/module.h>
25 #include <net/ethoc.h>
26 
27 static int buffer_size = 0x8000; /* 32 KBytes */
28 module_param(buffer_size, int, 0);
29 MODULE_PARM_DESC(buffer_size, "DMA buffer allocation size");
30 
31 /* register offsets */
32 #define	MODER		0x00
33 #define	INT_SOURCE	0x04
34 #define	INT_MASK	0x08
35 #define	IPGT		0x0c
36 #define	IPGR1		0x10
37 #define	IPGR2		0x14
38 #define	PACKETLEN	0x18
39 #define	COLLCONF	0x1c
40 #define	TX_BD_NUM	0x20
41 #define	CTRLMODER	0x24
42 #define	MIIMODER	0x28
43 #define	MIICOMMAND	0x2c
44 #define	MIIADDRESS	0x30
45 #define	MIITX_DATA	0x34
46 #define	MIIRX_DATA	0x38
47 #define	MIISTATUS	0x3c
48 #define	MAC_ADDR0	0x40
49 #define	MAC_ADDR1	0x44
50 #define	ETH_HASH0	0x48
51 #define	ETH_HASH1	0x4c
52 #define	ETH_TXCTRL	0x50
53 #define	ETH_END		0x54
54 
55 /* mode register */
56 #define	MODER_RXEN	(1 <<  0) /* receive enable */
57 #define	MODER_TXEN	(1 <<  1) /* transmit enable */
58 #define	MODER_NOPRE	(1 <<  2) /* no preamble */
59 #define	MODER_BRO	(1 <<  3) /* broadcast address */
60 #define	MODER_IAM	(1 <<  4) /* individual address mode */
61 #define	MODER_PRO	(1 <<  5) /* promiscuous mode */
62 #define	MODER_IFG	(1 <<  6) /* interframe gap for incoming frames */
63 #define	MODER_LOOP	(1 <<  7) /* loopback */
64 #define	MODER_NBO	(1 <<  8) /* no back-off */
65 #define	MODER_EDE	(1 <<  9) /* excess defer enable */
66 #define	MODER_FULLD	(1 << 10) /* full duplex */
67 #define	MODER_RESET	(1 << 11) /* FIXME: reset (undocumented) */
68 #define	MODER_DCRC	(1 << 12) /* delayed CRC enable */
69 #define	MODER_CRC	(1 << 13) /* CRC enable */
70 #define	MODER_HUGE	(1 << 14) /* huge packets enable */
71 #define	MODER_PAD	(1 << 15) /* padding enabled */
72 #define	MODER_RSM	(1 << 16) /* receive small packets */
73 
74 /* interrupt source and mask registers */
75 #define	INT_MASK_TXF	(1 << 0) /* transmit frame */
76 #define	INT_MASK_TXE	(1 << 1) /* transmit error */
77 #define	INT_MASK_RXF	(1 << 2) /* receive frame */
78 #define	INT_MASK_RXE	(1 << 3) /* receive error */
79 #define	INT_MASK_BUSY	(1 << 4)
80 #define	INT_MASK_TXC	(1 << 5) /* transmit control frame */
81 #define	INT_MASK_RXC	(1 << 6) /* receive control frame */
82 
83 #define	INT_MASK_TX	(INT_MASK_TXF | INT_MASK_TXE)
84 #define	INT_MASK_RX	(INT_MASK_RXF | INT_MASK_RXE)
85 
86 #define	INT_MASK_ALL ( \
87 		INT_MASK_TXF | INT_MASK_TXE | \
88 		INT_MASK_RXF | INT_MASK_RXE | \
89 		INT_MASK_TXC | INT_MASK_RXC | \
90 		INT_MASK_BUSY \
91 	)
92 
93 /* packet length register */
94 #define	PACKETLEN_MIN(min)		(((min) & 0xffff) << 16)
95 #define	PACKETLEN_MAX(max)		(((max) & 0xffff) <<  0)
96 #define	PACKETLEN_MIN_MAX(min, max)	(PACKETLEN_MIN(min) | \
97 					PACKETLEN_MAX(max))
98 
99 /* transmit buffer number register */
100 #define	TX_BD_NUM_VAL(x)	(((x) <= 0x80) ? (x) : 0x80)
101 
102 /* control module mode register */
103 #define	CTRLMODER_PASSALL	(1 << 0) /* pass all receive frames */
104 #define	CTRLMODER_RXFLOW	(1 << 1) /* receive control flow */
105 #define	CTRLMODER_TXFLOW	(1 << 2) /* transmit control flow */
106 
107 /* MII mode register */
108 #define	MIIMODER_CLKDIV(x)	((x) & 0xfe) /* needs to be an even number */
109 #define	MIIMODER_NOPRE		(1 << 8) /* no preamble */
110 
111 /* MII command register */
112 #define	MIICOMMAND_SCAN		(1 << 0) /* scan status */
113 #define	MIICOMMAND_READ		(1 << 1) /* read status */
114 #define	MIICOMMAND_WRITE	(1 << 2) /* write control data */
115 
116 /* MII address register */
117 #define	MIIADDRESS_FIAD(x)		(((x) & 0x1f) << 0)
118 #define	MIIADDRESS_RGAD(x)		(((x) & 0x1f) << 8)
119 #define	MIIADDRESS_ADDR(phy, reg)	(MIIADDRESS_FIAD(phy) | \
120 					MIIADDRESS_RGAD(reg))
121 
122 /* MII transmit data register */
123 #define	MIITX_DATA_VAL(x)	((x) & 0xffff)
124 
125 /* MII receive data register */
126 #define	MIIRX_DATA_VAL(x)	((x) & 0xffff)
127 
128 /* MII status register */
129 #define	MIISTATUS_LINKFAIL	(1 << 0)
130 #define	MIISTATUS_BUSY		(1 << 1)
131 #define	MIISTATUS_INVALID	(1 << 2)
132 
133 /* TX buffer descriptor */
134 #define	TX_BD_CS		(1 <<  0) /* carrier sense lost */
135 #define	TX_BD_DF		(1 <<  1) /* defer indication */
136 #define	TX_BD_LC		(1 <<  2) /* late collision */
137 #define	TX_BD_RL		(1 <<  3) /* retransmission limit */
138 #define	TX_BD_RETRY_MASK	(0x00f0)
139 #define	TX_BD_RETRY(x)		(((x) & 0x00f0) >>  4)
140 #define	TX_BD_UR		(1 <<  8) /* transmitter underrun */
141 #define	TX_BD_CRC		(1 << 11) /* TX CRC enable */
142 #define	TX_BD_PAD		(1 << 12) /* pad enable for short packets */
143 #define	TX_BD_WRAP		(1 << 13)
144 #define	TX_BD_IRQ		(1 << 14) /* interrupt request enable */
145 #define	TX_BD_READY		(1 << 15) /* TX buffer ready */
146 #define	TX_BD_LEN(x)		(((x) & 0xffff) << 16)
147 #define	TX_BD_LEN_MASK		(0xffff << 16)
148 
149 #define	TX_BD_STATS		(TX_BD_CS | TX_BD_DF | TX_BD_LC | \
150 				TX_BD_RL | TX_BD_RETRY_MASK | TX_BD_UR)
151 
152 /* RX buffer descriptor */
153 #define	RX_BD_LC	(1 <<  0) /* late collision */
154 #define	RX_BD_CRC	(1 <<  1) /* RX CRC error */
155 #define	RX_BD_SF	(1 <<  2) /* short frame */
156 #define	RX_BD_TL	(1 <<  3) /* too long */
157 #define	RX_BD_DN	(1 <<  4) /* dribble nibble */
158 #define	RX_BD_IS	(1 <<  5) /* invalid symbol */
159 #define	RX_BD_OR	(1 <<  6) /* receiver overrun */
160 #define	RX_BD_MISS	(1 <<  7)
161 #define	RX_BD_CF	(1 <<  8) /* control frame */
162 #define	RX_BD_WRAP	(1 << 13)
163 #define	RX_BD_IRQ	(1 << 14) /* interrupt request enable */
164 #define	RX_BD_EMPTY	(1 << 15)
165 #define	RX_BD_LEN(x)	(((x) & 0xffff) << 16)
166 
167 #define	RX_BD_STATS	(RX_BD_LC | RX_BD_CRC | RX_BD_SF | RX_BD_TL | \
168 			RX_BD_DN | RX_BD_IS | RX_BD_OR | RX_BD_MISS)
169 
170 #define	ETHOC_BUFSIZ		1536
171 #define	ETHOC_ZLEN		64
172 #define	ETHOC_BD_BASE		0x400
173 #define	ETHOC_TIMEOUT		(HZ / 2)
174 #define	ETHOC_MII_TIMEOUT	(1 + (HZ / 5))
175 
176 /**
177  * struct ethoc - driver-private device structure
178  * @iobase:	pointer to I/O memory region
179  * @membase:	pointer to buffer memory region
180  * @big_endian: just big or little (endian)
181  * @num_bd:	number of buffer descriptors
182  * @num_tx:	number of send buffers
183  * @cur_tx:	last send buffer written
184  * @dty_tx:	last buffer actually sent
185  * @num_rx:	number of receive buffers
186  * @cur_rx:	current receive buffer
187  * @vma:        pointer to array of virtual memory addresses for buffers
188  * @netdev:	pointer to network device structure
189  * @napi:	NAPI structure
190  * @msg_enable:	device state flags
191  * @lock:	device lock
192  * @mdio:	MDIO bus for PHY access
193  * @clk:	clock
194  * @phy_id:	address of attached PHY
195  * @old_link:	previous link info
196  * @old_duplex: previous duplex info
197  */
198 struct ethoc {
199 	void __iomem *iobase;
200 	void __iomem *membase;
201 	bool big_endian;
202 
203 	unsigned int num_bd;
204 	unsigned int num_tx;
205 	unsigned int cur_tx;
206 	unsigned int dty_tx;
207 
208 	unsigned int num_rx;
209 	unsigned int cur_rx;
210 
211 	void **vma;
212 
213 	struct net_device *netdev;
214 	struct napi_struct napi;
215 	u32 msg_enable;
216 
217 	spinlock_t lock;
218 
219 	struct mii_bus *mdio;
220 	struct clk *clk;
221 	s8 phy_id;
222 
223 	int old_link;
224 	int old_duplex;
225 };
226 
227 /**
228  * struct ethoc_bd - buffer descriptor
229  * @stat:	buffer statistics
230  * @addr:	physical memory address
231  */
232 struct ethoc_bd {
233 	u32 stat;
234 	u32 addr;
235 };
236 
237 static inline u32 ethoc_read(struct ethoc *dev, loff_t offset)
238 {
239 	if (dev->big_endian)
240 		return ioread32be(dev->iobase + offset);
241 	else
242 		return ioread32(dev->iobase + offset);
243 }
244 
245 static inline void ethoc_write(struct ethoc *dev, loff_t offset, u32 data)
246 {
247 	if (dev->big_endian)
248 		iowrite32be(data, dev->iobase + offset);
249 	else
250 		iowrite32(data, dev->iobase + offset);
251 }
252 
253 static inline void ethoc_read_bd(struct ethoc *dev, int index,
254 		struct ethoc_bd *bd)
255 {
256 	loff_t offset = ETHOC_BD_BASE + (index * sizeof(struct ethoc_bd));
257 	bd->stat = ethoc_read(dev, offset + 0);
258 	bd->addr = ethoc_read(dev, offset + 4);
259 }
260 
261 static inline void ethoc_write_bd(struct ethoc *dev, int index,
262 		const struct ethoc_bd *bd)
263 {
264 	loff_t offset = ETHOC_BD_BASE + (index * sizeof(struct ethoc_bd));
265 	ethoc_write(dev, offset + 0, bd->stat);
266 	ethoc_write(dev, offset + 4, bd->addr);
267 }
268 
269 static inline void ethoc_enable_irq(struct ethoc *dev, u32 mask)
270 {
271 	u32 imask = ethoc_read(dev, INT_MASK);
272 	imask |= mask;
273 	ethoc_write(dev, INT_MASK, imask);
274 }
275 
276 static inline void ethoc_disable_irq(struct ethoc *dev, u32 mask)
277 {
278 	u32 imask = ethoc_read(dev, INT_MASK);
279 	imask &= ~mask;
280 	ethoc_write(dev, INT_MASK, imask);
281 }
282 
283 static inline void ethoc_ack_irq(struct ethoc *dev, u32 mask)
284 {
285 	ethoc_write(dev, INT_SOURCE, mask);
286 }
287 
288 static inline void ethoc_enable_rx_and_tx(struct ethoc *dev)
289 {
290 	u32 mode = ethoc_read(dev, MODER);
291 	mode |= MODER_RXEN | MODER_TXEN;
292 	ethoc_write(dev, MODER, mode);
293 }
294 
295 static inline void ethoc_disable_rx_and_tx(struct ethoc *dev)
296 {
297 	u32 mode = ethoc_read(dev, MODER);
298 	mode &= ~(MODER_RXEN | MODER_TXEN);
299 	ethoc_write(dev, MODER, mode);
300 }
301 
302 static int ethoc_init_ring(struct ethoc *dev, unsigned long mem_start)
303 {
304 	struct ethoc_bd bd;
305 	int i;
306 	void *vma;
307 
308 	dev->cur_tx = 0;
309 	dev->dty_tx = 0;
310 	dev->cur_rx = 0;
311 
312 	ethoc_write(dev, TX_BD_NUM, dev->num_tx);
313 
314 	/* setup transmission buffers */
315 	bd.addr = mem_start;
316 	bd.stat = TX_BD_IRQ | TX_BD_CRC;
317 	vma = dev->membase;
318 
319 	for (i = 0; i < dev->num_tx; i++) {
320 		if (i == dev->num_tx - 1)
321 			bd.stat |= TX_BD_WRAP;
322 
323 		ethoc_write_bd(dev, i, &bd);
324 		bd.addr += ETHOC_BUFSIZ;
325 
326 		dev->vma[i] = vma;
327 		vma += ETHOC_BUFSIZ;
328 	}
329 
330 	bd.stat = RX_BD_EMPTY | RX_BD_IRQ;
331 
332 	for (i = 0; i < dev->num_rx; i++) {
333 		if (i == dev->num_rx - 1)
334 			bd.stat |= RX_BD_WRAP;
335 
336 		ethoc_write_bd(dev, dev->num_tx + i, &bd);
337 		bd.addr += ETHOC_BUFSIZ;
338 
339 		dev->vma[dev->num_tx + i] = vma;
340 		vma += ETHOC_BUFSIZ;
341 	}
342 
343 	return 0;
344 }
345 
346 static int ethoc_reset(struct ethoc *dev)
347 {
348 	u32 mode;
349 
350 	/* TODO: reset controller? */
351 
352 	ethoc_disable_rx_and_tx(dev);
353 
354 	/* TODO: setup registers */
355 
356 	/* enable FCS generation and automatic padding */
357 	mode = ethoc_read(dev, MODER);
358 	mode |= MODER_CRC | MODER_PAD;
359 	ethoc_write(dev, MODER, mode);
360 
361 	/* set full-duplex mode */
362 	mode = ethoc_read(dev, MODER);
363 	mode |= MODER_FULLD;
364 	ethoc_write(dev, MODER, mode);
365 	ethoc_write(dev, IPGT, 0x15);
366 
367 	ethoc_ack_irq(dev, INT_MASK_ALL);
368 	ethoc_enable_irq(dev, INT_MASK_ALL);
369 	ethoc_enable_rx_and_tx(dev);
370 	return 0;
371 }
372 
373 static unsigned int ethoc_update_rx_stats(struct ethoc *dev,
374 		struct ethoc_bd *bd)
375 {
376 	struct net_device *netdev = dev->netdev;
377 	unsigned int ret = 0;
378 
379 	if (bd->stat & RX_BD_TL) {
380 		dev_err(&netdev->dev, "RX: frame too long\n");
381 		netdev->stats.rx_length_errors++;
382 		ret++;
383 	}
384 
385 	if (bd->stat & RX_BD_SF) {
386 		dev_err(&netdev->dev, "RX: frame too short\n");
387 		netdev->stats.rx_length_errors++;
388 		ret++;
389 	}
390 
391 	if (bd->stat & RX_BD_DN) {
392 		dev_err(&netdev->dev, "RX: dribble nibble\n");
393 		netdev->stats.rx_frame_errors++;
394 	}
395 
396 	if (bd->stat & RX_BD_CRC) {
397 		dev_err(&netdev->dev, "RX: wrong CRC\n");
398 		netdev->stats.rx_crc_errors++;
399 		ret++;
400 	}
401 
402 	if (bd->stat & RX_BD_OR) {
403 		dev_err(&netdev->dev, "RX: overrun\n");
404 		netdev->stats.rx_over_errors++;
405 		ret++;
406 	}
407 
408 	if (bd->stat & RX_BD_MISS)
409 		netdev->stats.rx_missed_errors++;
410 
411 	if (bd->stat & RX_BD_LC) {
412 		dev_err(&netdev->dev, "RX: late collision\n");
413 		netdev->stats.collisions++;
414 		ret++;
415 	}
416 
417 	return ret;
418 }
419 
420 static int ethoc_rx(struct net_device *dev, int limit)
421 {
422 	struct ethoc *priv = netdev_priv(dev);
423 	int count;
424 
425 	for (count = 0; count < limit; ++count) {
426 		unsigned int entry;
427 		struct ethoc_bd bd;
428 
429 		entry = priv->num_tx + priv->cur_rx;
430 		ethoc_read_bd(priv, entry, &bd);
431 		if (bd.stat & RX_BD_EMPTY) {
432 			ethoc_ack_irq(priv, INT_MASK_RX);
433 			/* If packet (interrupt) came in between checking
434 			 * BD_EMTPY and clearing the interrupt source, then we
435 			 * risk missing the packet as the RX interrupt won't
436 			 * trigger right away when we reenable it; hence, check
437 			 * BD_EMTPY here again to make sure there isn't such a
438 			 * packet waiting for us...
439 			 */
440 			ethoc_read_bd(priv, entry, &bd);
441 			if (bd.stat & RX_BD_EMPTY)
442 				break;
443 		}
444 
445 		if (ethoc_update_rx_stats(priv, &bd) == 0) {
446 			int size = bd.stat >> 16;
447 			struct sk_buff *skb;
448 
449 			size -= 4; /* strip the CRC */
450 			skb = netdev_alloc_skb_ip_align(dev, size);
451 
452 			if (likely(skb)) {
453 				void *src = priv->vma[entry];
454 				memcpy_fromio(skb_put(skb, size), src, size);
455 				skb->protocol = eth_type_trans(skb, dev);
456 				dev->stats.rx_packets++;
457 				dev->stats.rx_bytes += size;
458 				netif_receive_skb(skb);
459 			} else {
460 				if (net_ratelimit())
461 					dev_warn(&dev->dev,
462 					    "low on memory - packet dropped\n");
463 
464 				dev->stats.rx_dropped++;
465 				break;
466 			}
467 		}
468 
469 		/* clear the buffer descriptor so it can be reused */
470 		bd.stat &= ~RX_BD_STATS;
471 		bd.stat |=  RX_BD_EMPTY;
472 		ethoc_write_bd(priv, entry, &bd);
473 		if (++priv->cur_rx == priv->num_rx)
474 			priv->cur_rx = 0;
475 	}
476 
477 	return count;
478 }
479 
480 static void ethoc_update_tx_stats(struct ethoc *dev, struct ethoc_bd *bd)
481 {
482 	struct net_device *netdev = dev->netdev;
483 
484 	if (bd->stat & TX_BD_LC) {
485 		dev_err(&netdev->dev, "TX: late collision\n");
486 		netdev->stats.tx_window_errors++;
487 	}
488 
489 	if (bd->stat & TX_BD_RL) {
490 		dev_err(&netdev->dev, "TX: retransmit limit\n");
491 		netdev->stats.tx_aborted_errors++;
492 	}
493 
494 	if (bd->stat & TX_BD_UR) {
495 		dev_err(&netdev->dev, "TX: underrun\n");
496 		netdev->stats.tx_fifo_errors++;
497 	}
498 
499 	if (bd->stat & TX_BD_CS) {
500 		dev_err(&netdev->dev, "TX: carrier sense lost\n");
501 		netdev->stats.tx_carrier_errors++;
502 	}
503 
504 	if (bd->stat & TX_BD_STATS)
505 		netdev->stats.tx_errors++;
506 
507 	netdev->stats.collisions += (bd->stat >> 4) & 0xf;
508 	netdev->stats.tx_bytes += bd->stat >> 16;
509 	netdev->stats.tx_packets++;
510 }
511 
512 static int ethoc_tx(struct net_device *dev, int limit)
513 {
514 	struct ethoc *priv = netdev_priv(dev);
515 	int count;
516 	struct ethoc_bd bd;
517 
518 	for (count = 0; count < limit; ++count) {
519 		unsigned int entry;
520 
521 		entry = priv->dty_tx & (priv->num_tx-1);
522 
523 		ethoc_read_bd(priv, entry, &bd);
524 
525 		if (bd.stat & TX_BD_READY || (priv->dty_tx == priv->cur_tx)) {
526 			ethoc_ack_irq(priv, INT_MASK_TX);
527 			/* If interrupt came in between reading in the BD
528 			 * and clearing the interrupt source, then we risk
529 			 * missing the event as the TX interrupt won't trigger
530 			 * right away when we reenable it; hence, check
531 			 * BD_EMPTY here again to make sure there isn't such an
532 			 * event pending...
533 			 */
534 			ethoc_read_bd(priv, entry, &bd);
535 			if (bd.stat & TX_BD_READY ||
536 			    (priv->dty_tx == priv->cur_tx))
537 				break;
538 		}
539 
540 		ethoc_update_tx_stats(priv, &bd);
541 		priv->dty_tx++;
542 	}
543 
544 	if ((priv->cur_tx - priv->dty_tx) <= (priv->num_tx / 2))
545 		netif_wake_queue(dev);
546 
547 	return count;
548 }
549 
550 static irqreturn_t ethoc_interrupt(int irq, void *dev_id)
551 {
552 	struct net_device *dev = dev_id;
553 	struct ethoc *priv = netdev_priv(dev);
554 	u32 pending;
555 	u32 mask;
556 
557 	/* Figure out what triggered the interrupt...
558 	 * The tricky bit here is that the interrupt source bits get
559 	 * set in INT_SOURCE for an event regardless of whether that
560 	 * event is masked or not.  Thus, in order to figure out what
561 	 * triggered the interrupt, we need to remove the sources
562 	 * for all events that are currently masked.  This behaviour
563 	 * is not particularly well documented but reasonable...
564 	 */
565 	mask = ethoc_read(priv, INT_MASK);
566 	pending = ethoc_read(priv, INT_SOURCE);
567 	pending &= mask;
568 
569 	if (unlikely(pending == 0))
570 		return IRQ_NONE;
571 
572 	ethoc_ack_irq(priv, pending);
573 
574 	/* We always handle the dropped packet interrupt */
575 	if (pending & INT_MASK_BUSY) {
576 		dev_dbg(&dev->dev, "packet dropped\n");
577 		dev->stats.rx_dropped++;
578 	}
579 
580 	/* Handle receive/transmit event by switching to polling */
581 	if (pending & (INT_MASK_TX | INT_MASK_RX)) {
582 		ethoc_disable_irq(priv, INT_MASK_TX | INT_MASK_RX);
583 		napi_schedule(&priv->napi);
584 	}
585 
586 	return IRQ_HANDLED;
587 }
588 
589 static int ethoc_get_mac_address(struct net_device *dev, void *addr)
590 {
591 	struct ethoc *priv = netdev_priv(dev);
592 	u8 *mac = (u8 *)addr;
593 	u32 reg;
594 
595 	reg = ethoc_read(priv, MAC_ADDR0);
596 	mac[2] = (reg >> 24) & 0xff;
597 	mac[3] = (reg >> 16) & 0xff;
598 	mac[4] = (reg >>  8) & 0xff;
599 	mac[5] = (reg >>  0) & 0xff;
600 
601 	reg = ethoc_read(priv, MAC_ADDR1);
602 	mac[0] = (reg >>  8) & 0xff;
603 	mac[1] = (reg >>  0) & 0xff;
604 
605 	return 0;
606 }
607 
608 static int ethoc_poll(struct napi_struct *napi, int budget)
609 {
610 	struct ethoc *priv = container_of(napi, struct ethoc, napi);
611 	int rx_work_done = 0;
612 	int tx_work_done = 0;
613 
614 	rx_work_done = ethoc_rx(priv->netdev, budget);
615 	tx_work_done = ethoc_tx(priv->netdev, budget);
616 
617 	if (rx_work_done < budget && tx_work_done < budget) {
618 		napi_complete_done(napi, rx_work_done);
619 		ethoc_enable_irq(priv, INT_MASK_TX | INT_MASK_RX);
620 	}
621 
622 	return rx_work_done;
623 }
624 
625 static int ethoc_mdio_read(struct mii_bus *bus, int phy, int reg)
626 {
627 	struct ethoc *priv = bus->priv;
628 	int i;
629 
630 	ethoc_write(priv, MIIADDRESS, MIIADDRESS_ADDR(phy, reg));
631 	ethoc_write(priv, MIICOMMAND, MIICOMMAND_READ);
632 
633 	for (i = 0; i < 5; i++) {
634 		u32 status = ethoc_read(priv, MIISTATUS);
635 		if (!(status & MIISTATUS_BUSY)) {
636 			u32 data = ethoc_read(priv, MIIRX_DATA);
637 			/* reset MII command register */
638 			ethoc_write(priv, MIICOMMAND, 0);
639 			return data;
640 		}
641 		usleep_range(100, 200);
642 	}
643 
644 	return -EBUSY;
645 }
646 
647 static int ethoc_mdio_write(struct mii_bus *bus, int phy, int reg, u16 val)
648 {
649 	struct ethoc *priv = bus->priv;
650 	int i;
651 
652 	ethoc_write(priv, MIIADDRESS, MIIADDRESS_ADDR(phy, reg));
653 	ethoc_write(priv, MIITX_DATA, val);
654 	ethoc_write(priv, MIICOMMAND, MIICOMMAND_WRITE);
655 
656 	for (i = 0; i < 5; i++) {
657 		u32 stat = ethoc_read(priv, MIISTATUS);
658 		if (!(stat & MIISTATUS_BUSY)) {
659 			/* reset MII command register */
660 			ethoc_write(priv, MIICOMMAND, 0);
661 			return 0;
662 		}
663 		usleep_range(100, 200);
664 	}
665 
666 	return -EBUSY;
667 }
668 
669 static void ethoc_mdio_poll(struct net_device *dev)
670 {
671 	struct ethoc *priv = netdev_priv(dev);
672 	struct phy_device *phydev = dev->phydev;
673 	bool changed = false;
674 	u32 mode;
675 
676 	if (priv->old_link != phydev->link) {
677 		changed = true;
678 		priv->old_link = phydev->link;
679 	}
680 
681 	if (priv->old_duplex != phydev->duplex) {
682 		changed = true;
683 		priv->old_duplex = phydev->duplex;
684 	}
685 
686 	if (!changed)
687 		return;
688 
689 	mode = ethoc_read(priv, MODER);
690 	if (phydev->duplex == DUPLEX_FULL)
691 		mode |= MODER_FULLD;
692 	else
693 		mode &= ~MODER_FULLD;
694 	ethoc_write(priv, MODER, mode);
695 
696 	phy_print_status(phydev);
697 }
698 
699 static int ethoc_mdio_probe(struct net_device *dev)
700 {
701 	struct ethoc *priv = netdev_priv(dev);
702 	struct phy_device *phy;
703 	int err;
704 
705 	if (priv->phy_id != -1)
706 		phy = mdiobus_get_phy(priv->mdio, priv->phy_id);
707 	else
708 		phy = phy_find_first(priv->mdio);
709 
710 	if (!phy)
711 		return dev_err_probe(&dev->dev, -ENXIO, "no PHY found\n");
712 
713 	priv->old_duplex = -1;
714 	priv->old_link = -1;
715 
716 	err = phy_connect_direct(dev, phy, ethoc_mdio_poll,
717 				 PHY_INTERFACE_MODE_GMII);
718 	if (err)
719 		return dev_err_probe(&dev->dev, err, "could not attach to PHY\n");
720 
721 	phy_set_max_speed(phy, SPEED_100);
722 
723 	return 0;
724 }
725 
726 static int ethoc_open(struct net_device *dev)
727 {
728 	struct ethoc *priv = netdev_priv(dev);
729 	int ret;
730 
731 	ret = request_irq(dev->irq, ethoc_interrupt, IRQF_SHARED,
732 			dev->name, dev);
733 	if (ret)
734 		return ret;
735 
736 	napi_enable(&priv->napi);
737 
738 	ethoc_init_ring(priv, dev->mem_start);
739 	ethoc_reset(priv);
740 
741 	if (netif_queue_stopped(dev)) {
742 		dev_dbg(&dev->dev, " resuming queue\n");
743 		netif_wake_queue(dev);
744 	} else {
745 		dev_dbg(&dev->dev, " starting queue\n");
746 		netif_start_queue(dev);
747 	}
748 
749 	priv->old_link = -1;
750 	priv->old_duplex = -1;
751 
752 	phy_start(dev->phydev);
753 
754 	if (netif_msg_ifup(priv)) {
755 		dev_info(&dev->dev, "I/O: %08lx Memory: %08lx-%08lx\n",
756 				dev->base_addr, dev->mem_start, dev->mem_end);
757 	}
758 
759 	return 0;
760 }
761 
762 static int ethoc_stop(struct net_device *dev)
763 {
764 	struct ethoc *priv = netdev_priv(dev);
765 
766 	napi_disable(&priv->napi);
767 
768 	if (dev->phydev)
769 		phy_stop(dev->phydev);
770 
771 	ethoc_disable_rx_and_tx(priv);
772 	free_irq(dev->irq, dev);
773 
774 	if (!netif_queue_stopped(dev))
775 		netif_stop_queue(dev);
776 
777 	return 0;
778 }
779 
780 static int ethoc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
781 {
782 	struct ethoc *priv = netdev_priv(dev);
783 	struct mii_ioctl_data *mdio = if_mii(ifr);
784 	struct phy_device *phy = NULL;
785 
786 	if (!netif_running(dev))
787 		return -EINVAL;
788 
789 	if (cmd != SIOCGMIIPHY) {
790 		if (mdio->phy_id >= PHY_MAX_ADDR)
791 			return -ERANGE;
792 
793 		phy = mdiobus_get_phy(priv->mdio, mdio->phy_id);
794 		if (!phy)
795 			return -ENODEV;
796 	} else {
797 		phy = dev->phydev;
798 	}
799 
800 	return phy_mii_ioctl(phy, ifr, cmd);
801 }
802 
803 static void ethoc_do_set_mac_address(struct net_device *dev)
804 {
805 	const unsigned char *mac = dev->dev_addr;
806 	struct ethoc *priv = netdev_priv(dev);
807 
808 	ethoc_write(priv, MAC_ADDR0, (mac[2] << 24) | (mac[3] << 16) |
809 				     (mac[4] <<  8) | (mac[5] <<  0));
810 	ethoc_write(priv, MAC_ADDR1, (mac[0] <<  8) | (mac[1] <<  0));
811 }
812 
813 static int ethoc_set_mac_address(struct net_device *dev, void *p)
814 {
815 	const struct sockaddr *addr = p;
816 
817 	if (!is_valid_ether_addr(addr->sa_data))
818 		return -EADDRNOTAVAIL;
819 	eth_hw_addr_set(dev, addr->sa_data);
820 	ethoc_do_set_mac_address(dev);
821 	return 0;
822 }
823 
824 static void ethoc_set_multicast_list(struct net_device *dev)
825 {
826 	struct ethoc *priv = netdev_priv(dev);
827 	u32 mode = ethoc_read(priv, MODER);
828 	struct netdev_hw_addr *ha;
829 	u32 hash[2] = { 0, 0 };
830 
831 	/* set loopback mode if requested */
832 	if (dev->flags & IFF_LOOPBACK)
833 		mode |=  MODER_LOOP;
834 	else
835 		mode &= ~MODER_LOOP;
836 
837 	/* receive broadcast frames if requested */
838 	if (dev->flags & IFF_BROADCAST)
839 		mode &= ~MODER_BRO;
840 	else
841 		mode |=  MODER_BRO;
842 
843 	/* enable promiscuous mode if requested */
844 	if (dev->flags & IFF_PROMISC)
845 		mode |=  MODER_PRO;
846 	else
847 		mode &= ~MODER_PRO;
848 
849 	ethoc_write(priv, MODER, mode);
850 
851 	/* receive multicast frames */
852 	if (dev->flags & IFF_ALLMULTI) {
853 		hash[0] = 0xffffffff;
854 		hash[1] = 0xffffffff;
855 	} else {
856 		netdev_for_each_mc_addr(ha, dev) {
857 			u32 crc = ether_crc(ETH_ALEN, ha->addr);
858 			int bit = (crc >> 26) & 0x3f;
859 			hash[bit >> 5] |= 1 << (bit & 0x1f);
860 		}
861 	}
862 
863 	ethoc_write(priv, ETH_HASH0, hash[0]);
864 	ethoc_write(priv, ETH_HASH1, hash[1]);
865 }
866 
867 static int ethoc_change_mtu(struct net_device *dev, int new_mtu)
868 {
869 	return -ENOSYS;
870 }
871 
872 static void ethoc_tx_timeout(struct net_device *dev, unsigned int txqueue)
873 {
874 	struct ethoc *priv = netdev_priv(dev);
875 	u32 pending = ethoc_read(priv, INT_SOURCE);
876 	if (likely(pending))
877 		ethoc_interrupt(dev->irq, dev);
878 }
879 
880 static netdev_tx_t ethoc_start_xmit(struct sk_buff *skb, struct net_device *dev)
881 {
882 	struct ethoc *priv = netdev_priv(dev);
883 	struct ethoc_bd bd;
884 	unsigned int entry;
885 	void *dest;
886 
887 	if (skb_put_padto(skb, ETHOC_ZLEN)) {
888 		dev->stats.tx_errors++;
889 		goto out_no_free;
890 	}
891 
892 	if (unlikely(skb->len > ETHOC_BUFSIZ)) {
893 		dev->stats.tx_errors++;
894 		goto out;
895 	}
896 
897 	entry = priv->cur_tx % priv->num_tx;
898 	spin_lock_irq(&priv->lock);
899 	priv->cur_tx++;
900 
901 	ethoc_read_bd(priv, entry, &bd);
902 	if (unlikely(skb->len < ETHOC_ZLEN))
903 		bd.stat |=  TX_BD_PAD;
904 	else
905 		bd.stat &= ~TX_BD_PAD;
906 
907 	dest = priv->vma[entry];
908 	memcpy_toio(dest, skb->data, skb->len);
909 
910 	bd.stat &= ~(TX_BD_STATS | TX_BD_LEN_MASK);
911 	bd.stat |= TX_BD_LEN(skb->len);
912 	ethoc_write_bd(priv, entry, &bd);
913 
914 	bd.stat |= TX_BD_READY;
915 	ethoc_write_bd(priv, entry, &bd);
916 
917 	if (priv->cur_tx == (priv->dty_tx + priv->num_tx)) {
918 		dev_dbg(&dev->dev, "stopping queue\n");
919 		netif_stop_queue(dev);
920 	}
921 
922 	spin_unlock_irq(&priv->lock);
923 	skb_tx_timestamp(skb);
924 out:
925 	dev_kfree_skb(skb);
926 out_no_free:
927 	return NETDEV_TX_OK;
928 }
929 
930 static int ethoc_get_regs_len(struct net_device *netdev)
931 {
932 	return ETH_END;
933 }
934 
935 static void ethoc_get_regs(struct net_device *dev, struct ethtool_regs *regs,
936 			   void *p)
937 {
938 	struct ethoc *priv = netdev_priv(dev);
939 	u32 *regs_buff = p;
940 	unsigned i;
941 
942 	regs->version = 0;
943 	for (i = 0; i < ETH_END / sizeof(u32); ++i)
944 		regs_buff[i] = ethoc_read(priv, i * sizeof(u32));
945 }
946 
947 static void ethoc_get_ringparam(struct net_device *dev,
948 				struct ethtool_ringparam *ring,
949 				struct kernel_ethtool_ringparam *kernel_ring,
950 				struct netlink_ext_ack *extack)
951 {
952 	struct ethoc *priv = netdev_priv(dev);
953 
954 	ring->rx_max_pending = priv->num_bd - 1;
955 	ring->rx_mini_max_pending = 0;
956 	ring->rx_jumbo_max_pending = 0;
957 	ring->tx_max_pending = priv->num_bd - 1;
958 
959 	ring->rx_pending = priv->num_rx;
960 	ring->rx_mini_pending = 0;
961 	ring->rx_jumbo_pending = 0;
962 	ring->tx_pending = priv->num_tx;
963 }
964 
965 static int ethoc_set_ringparam(struct net_device *dev,
966 			       struct ethtool_ringparam *ring,
967 			       struct kernel_ethtool_ringparam *kernel_ring,
968 			       struct netlink_ext_ack *extack)
969 {
970 	struct ethoc *priv = netdev_priv(dev);
971 
972 	if (ring->tx_pending < 1 || ring->rx_pending < 1 ||
973 	    ring->tx_pending + ring->rx_pending > priv->num_bd)
974 		return -EINVAL;
975 	if (ring->rx_mini_pending || ring->rx_jumbo_pending)
976 		return -EINVAL;
977 
978 	if (netif_running(dev)) {
979 		netif_tx_disable(dev);
980 		ethoc_disable_rx_and_tx(priv);
981 		ethoc_disable_irq(priv, INT_MASK_TX | INT_MASK_RX);
982 		synchronize_irq(dev->irq);
983 	}
984 
985 	priv->num_tx = rounddown_pow_of_two(ring->tx_pending);
986 	priv->num_rx = ring->rx_pending;
987 	ethoc_init_ring(priv, dev->mem_start);
988 
989 	if (netif_running(dev)) {
990 		ethoc_enable_irq(priv, INT_MASK_TX | INT_MASK_RX);
991 		ethoc_enable_rx_and_tx(priv);
992 		netif_wake_queue(dev);
993 	}
994 	return 0;
995 }
996 
997 static const struct ethtool_ops ethoc_ethtool_ops = {
998 	.get_regs_len = ethoc_get_regs_len,
999 	.get_regs = ethoc_get_regs,
1000 	.nway_reset = phy_ethtool_nway_reset,
1001 	.get_link = ethtool_op_get_link,
1002 	.get_ringparam = ethoc_get_ringparam,
1003 	.set_ringparam = ethoc_set_ringparam,
1004 	.get_ts_info = ethtool_op_get_ts_info,
1005 	.get_link_ksettings = phy_ethtool_get_link_ksettings,
1006 	.set_link_ksettings = phy_ethtool_set_link_ksettings,
1007 };
1008 
1009 static const struct net_device_ops ethoc_netdev_ops = {
1010 	.ndo_open = ethoc_open,
1011 	.ndo_stop = ethoc_stop,
1012 	.ndo_eth_ioctl = ethoc_ioctl,
1013 	.ndo_set_mac_address = ethoc_set_mac_address,
1014 	.ndo_set_rx_mode = ethoc_set_multicast_list,
1015 	.ndo_change_mtu = ethoc_change_mtu,
1016 	.ndo_tx_timeout = ethoc_tx_timeout,
1017 	.ndo_start_xmit = ethoc_start_xmit,
1018 };
1019 
1020 /**
1021  * ethoc_probe - initialize OpenCores ethernet MAC
1022  * @pdev:	platform device
1023  */
1024 static int ethoc_probe(struct platform_device *pdev)
1025 {
1026 	struct net_device *netdev = NULL;
1027 	struct resource *res = NULL;
1028 	struct resource *mmio = NULL;
1029 	struct resource *mem = NULL;
1030 	struct ethoc *priv = NULL;
1031 	int num_bd;
1032 	int ret = 0;
1033 	struct ethoc_platform_data *pdata = dev_get_platdata(&pdev->dev);
1034 	u32 eth_clkfreq = pdata ? pdata->eth_clkfreq : 0;
1035 
1036 	/* allocate networking device */
1037 	netdev = alloc_etherdev(sizeof(struct ethoc));
1038 	if (!netdev) {
1039 		ret = -ENOMEM;
1040 		goto out;
1041 	}
1042 
1043 	SET_NETDEV_DEV(netdev, &pdev->dev);
1044 	platform_set_drvdata(pdev, netdev);
1045 
1046 	/* obtain I/O memory space */
1047 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1048 	if (!res) {
1049 		dev_err(&pdev->dev, "cannot obtain I/O memory space\n");
1050 		ret = -ENXIO;
1051 		goto free;
1052 	}
1053 
1054 	mmio = devm_request_mem_region(&pdev->dev, res->start,
1055 			resource_size(res), res->name);
1056 	if (!mmio) {
1057 		dev_err(&pdev->dev, "cannot request I/O memory space\n");
1058 		ret = -ENXIO;
1059 		goto free;
1060 	}
1061 
1062 	netdev->base_addr = mmio->start;
1063 
1064 	/* obtain buffer memory space */
1065 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1066 	if (res) {
1067 		mem = devm_request_mem_region(&pdev->dev, res->start,
1068 			resource_size(res), res->name);
1069 		if (!mem) {
1070 			dev_err(&pdev->dev, "cannot request memory space\n");
1071 			ret = -ENXIO;
1072 			goto free;
1073 		}
1074 
1075 		netdev->mem_start = mem->start;
1076 		netdev->mem_end   = mem->end;
1077 	}
1078 
1079 
1080 	/* obtain device IRQ number */
1081 	ret = platform_get_irq(pdev, 0);
1082 	if (ret < 0)
1083 		goto free;
1084 
1085 	netdev->irq = ret;
1086 
1087 	/* setup driver-private data */
1088 	priv = netdev_priv(netdev);
1089 	priv->netdev = netdev;
1090 
1091 	priv->iobase = devm_ioremap(&pdev->dev, netdev->base_addr,
1092 			resource_size(mmio));
1093 	if (!priv->iobase) {
1094 		dev_err(&pdev->dev, "cannot remap I/O memory space\n");
1095 		ret = -ENXIO;
1096 		goto free;
1097 	}
1098 
1099 	if (netdev->mem_end) {
1100 		priv->membase = devm_ioremap(&pdev->dev,
1101 			netdev->mem_start, resource_size(mem));
1102 		if (!priv->membase) {
1103 			dev_err(&pdev->dev, "cannot remap memory space\n");
1104 			ret = -ENXIO;
1105 			goto free;
1106 		}
1107 	} else {
1108 		/* Allocate buffer memory */
1109 		priv->membase = dmam_alloc_coherent(&pdev->dev,
1110 			buffer_size, (void *)&netdev->mem_start,
1111 			GFP_KERNEL);
1112 		if (!priv->membase) {
1113 			dev_err(&pdev->dev, "cannot allocate %dB buffer\n",
1114 				buffer_size);
1115 			ret = -ENOMEM;
1116 			goto free;
1117 		}
1118 		netdev->mem_end = netdev->mem_start + buffer_size;
1119 	}
1120 
1121 	priv->big_endian = pdata ? pdata->big_endian :
1122 		of_device_is_big_endian(pdev->dev.of_node);
1123 
1124 	/* calculate the number of TX/RX buffers, maximum 128 supported */
1125 	num_bd = min_t(unsigned int,
1126 		128, (netdev->mem_end - netdev->mem_start + 1) / ETHOC_BUFSIZ);
1127 	if (num_bd < 4) {
1128 		ret = -ENODEV;
1129 		goto free;
1130 	}
1131 	priv->num_bd = num_bd;
1132 	/* num_tx must be a power of two */
1133 	priv->num_tx = rounddown_pow_of_two(num_bd >> 1);
1134 	priv->num_rx = num_bd - priv->num_tx;
1135 
1136 	dev_dbg(&pdev->dev, "ethoc: num_tx: %d num_rx: %d\n",
1137 		priv->num_tx, priv->num_rx);
1138 
1139 	priv->vma = devm_kcalloc(&pdev->dev, num_bd, sizeof(void *),
1140 				 GFP_KERNEL);
1141 	if (!priv->vma) {
1142 		ret = -ENOMEM;
1143 		goto free;
1144 	}
1145 
1146 	/* Allow the platform setup code to pass in a MAC address. */
1147 	if (pdata) {
1148 		eth_hw_addr_set(netdev, pdata->hwaddr);
1149 		priv->phy_id = pdata->phy_id;
1150 	} else {
1151 		of_get_ethdev_address(pdev->dev.of_node, netdev);
1152 		priv->phy_id = -1;
1153 	}
1154 
1155 	/* Check that the given MAC address is valid. If it isn't, read the
1156 	 * current MAC from the controller.
1157 	 */
1158 	if (!is_valid_ether_addr(netdev->dev_addr)) {
1159 		u8 addr[ETH_ALEN];
1160 
1161 		ethoc_get_mac_address(netdev, addr);
1162 		eth_hw_addr_set(netdev, addr);
1163 	}
1164 
1165 	/* Check the MAC again for validity, if it still isn't choose and
1166 	 * program a random one.
1167 	 */
1168 	if (!is_valid_ether_addr(netdev->dev_addr))
1169 		eth_hw_addr_random(netdev);
1170 
1171 	ethoc_do_set_mac_address(netdev);
1172 
1173 	/* Allow the platform setup code to adjust MII management bus clock. */
1174 	if (!eth_clkfreq) {
1175 		struct clk *clk = devm_clk_get(&pdev->dev, NULL);
1176 
1177 		if (!IS_ERR(clk)) {
1178 			priv->clk = clk;
1179 			clk_prepare_enable(clk);
1180 			eth_clkfreq = clk_get_rate(clk);
1181 		}
1182 	}
1183 	if (eth_clkfreq) {
1184 		u32 clkdiv = MIIMODER_CLKDIV(eth_clkfreq / 2500000 + 1);
1185 
1186 		if (!clkdiv)
1187 			clkdiv = 2;
1188 		dev_dbg(&pdev->dev, "setting MII clkdiv to %u\n", clkdiv);
1189 		ethoc_write(priv, MIIMODER,
1190 			    (ethoc_read(priv, MIIMODER) & MIIMODER_NOPRE) |
1191 			    clkdiv);
1192 	}
1193 
1194 	/* register MII bus */
1195 	priv->mdio = mdiobus_alloc();
1196 	if (!priv->mdio) {
1197 		ret = -ENOMEM;
1198 		goto free2;
1199 	}
1200 
1201 	priv->mdio->name = "ethoc-mdio";
1202 	snprintf(priv->mdio->id, MII_BUS_ID_SIZE, "%s-%d",
1203 			priv->mdio->name, pdev->id);
1204 	priv->mdio->read = ethoc_mdio_read;
1205 	priv->mdio->write = ethoc_mdio_write;
1206 	priv->mdio->priv = priv;
1207 
1208 	ret = mdiobus_register(priv->mdio);
1209 	if (ret) {
1210 		dev_err(&netdev->dev, "failed to register MDIO bus\n");
1211 		goto free3;
1212 	}
1213 
1214 	ret = ethoc_mdio_probe(netdev);
1215 	if (ret) {
1216 		dev_err(&netdev->dev, "failed to probe MDIO bus\n");
1217 		goto error;
1218 	}
1219 
1220 	/* setup the net_device structure */
1221 	netdev->netdev_ops = &ethoc_netdev_ops;
1222 	netdev->watchdog_timeo = ETHOC_TIMEOUT;
1223 	netdev->features |= 0;
1224 	netdev->ethtool_ops = &ethoc_ethtool_ops;
1225 
1226 	/* setup NAPI */
1227 	netif_napi_add(netdev, &priv->napi, ethoc_poll);
1228 
1229 	spin_lock_init(&priv->lock);
1230 
1231 	ret = register_netdev(netdev);
1232 	if (ret < 0) {
1233 		dev_err(&netdev->dev, "failed to register interface\n");
1234 		goto error2;
1235 	}
1236 
1237 	goto out;
1238 
1239 error2:
1240 	netif_napi_del(&priv->napi);
1241 error:
1242 	mdiobus_unregister(priv->mdio);
1243 free3:
1244 	mdiobus_free(priv->mdio);
1245 free2:
1246 	clk_disable_unprepare(priv->clk);
1247 free:
1248 	free_netdev(netdev);
1249 out:
1250 	return ret;
1251 }
1252 
1253 /**
1254  * ethoc_remove - shutdown OpenCores ethernet MAC
1255  * @pdev:	platform device
1256  */
1257 static void ethoc_remove(struct platform_device *pdev)
1258 {
1259 	struct net_device *netdev = platform_get_drvdata(pdev);
1260 	struct ethoc *priv = netdev_priv(netdev);
1261 
1262 	if (netdev) {
1263 		netif_napi_del(&priv->napi);
1264 		phy_disconnect(netdev->phydev);
1265 
1266 		if (priv->mdio) {
1267 			mdiobus_unregister(priv->mdio);
1268 			mdiobus_free(priv->mdio);
1269 		}
1270 		clk_disable_unprepare(priv->clk);
1271 		unregister_netdev(netdev);
1272 		free_netdev(netdev);
1273 	}
1274 }
1275 
1276 #ifdef CONFIG_PM
1277 static int ethoc_suspend(struct platform_device *pdev, pm_message_t state)
1278 {
1279 	return -ENOSYS;
1280 }
1281 
1282 static int ethoc_resume(struct platform_device *pdev)
1283 {
1284 	return -ENOSYS;
1285 }
1286 #else
1287 # define ethoc_suspend NULL
1288 # define ethoc_resume  NULL
1289 #endif
1290 
1291 static const struct of_device_id ethoc_match[] = {
1292 	{ .compatible = "opencores,ethoc", },
1293 	{},
1294 };
1295 MODULE_DEVICE_TABLE(of, ethoc_match);
1296 
1297 static struct platform_driver ethoc_driver = {
1298 	.probe   = ethoc_probe,
1299 	.remove = ethoc_remove,
1300 	.suspend = ethoc_suspend,
1301 	.resume  = ethoc_resume,
1302 	.driver  = {
1303 		.name = "ethoc",
1304 		.of_match_table = ethoc_match,
1305 	},
1306 };
1307 
1308 module_platform_driver(ethoc_driver);
1309 
1310 MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
1311 MODULE_DESCRIPTION("OpenCores Ethernet MAC driver");
1312 MODULE_LICENSE("GPL v2");
1313 
1314