xref: /openbmc/linux/drivers/net/ethernet/ethoc.c (revision 3a83e4e6)
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  * @num_bd:	number of buffer descriptors
181  * @num_tx:	number of send buffers
182  * @cur_tx:	last send buffer written
183  * @dty_tx:	last buffer actually sent
184  * @num_rx:	number of receive buffers
185  * @cur_rx:	current receive buffer
186  * @vma:        pointer to array of virtual memory addresses for buffers
187  * @netdev:	pointer to network device structure
188  * @napi:	NAPI structure
189  * @msg_enable:	device state flags
190  * @lock:	device lock
191  * @mdio:	MDIO bus for PHY access
192  * @phy_id:	address of attached PHY
193  */
194 struct ethoc {
195 	void __iomem *iobase;
196 	void __iomem *membase;
197 	bool big_endian;
198 
199 	unsigned int num_bd;
200 	unsigned int num_tx;
201 	unsigned int cur_tx;
202 	unsigned int dty_tx;
203 
204 	unsigned int num_rx;
205 	unsigned int cur_rx;
206 
207 	void **vma;
208 
209 	struct net_device *netdev;
210 	struct napi_struct napi;
211 	u32 msg_enable;
212 
213 	spinlock_t lock;
214 
215 	struct mii_bus *mdio;
216 	struct clk *clk;
217 	s8 phy_id;
218 
219 	int old_link;
220 	int old_duplex;
221 };
222 
223 /**
224  * struct ethoc_bd - buffer descriptor
225  * @stat:	buffer statistics
226  * @addr:	physical memory address
227  */
228 struct ethoc_bd {
229 	u32 stat;
230 	u32 addr;
231 };
232 
233 static inline u32 ethoc_read(struct ethoc *dev, loff_t offset)
234 {
235 	if (dev->big_endian)
236 		return ioread32be(dev->iobase + offset);
237 	else
238 		return ioread32(dev->iobase + offset);
239 }
240 
241 static inline void ethoc_write(struct ethoc *dev, loff_t offset, u32 data)
242 {
243 	if (dev->big_endian)
244 		iowrite32be(data, dev->iobase + offset);
245 	else
246 		iowrite32(data, dev->iobase + offset);
247 }
248 
249 static inline void ethoc_read_bd(struct ethoc *dev, int index,
250 		struct ethoc_bd *bd)
251 {
252 	loff_t offset = ETHOC_BD_BASE + (index * sizeof(struct ethoc_bd));
253 	bd->stat = ethoc_read(dev, offset + 0);
254 	bd->addr = ethoc_read(dev, offset + 4);
255 }
256 
257 static inline void ethoc_write_bd(struct ethoc *dev, int index,
258 		const struct ethoc_bd *bd)
259 {
260 	loff_t offset = ETHOC_BD_BASE + (index * sizeof(struct ethoc_bd));
261 	ethoc_write(dev, offset + 0, bd->stat);
262 	ethoc_write(dev, offset + 4, bd->addr);
263 }
264 
265 static inline void ethoc_enable_irq(struct ethoc *dev, u32 mask)
266 {
267 	u32 imask = ethoc_read(dev, INT_MASK);
268 	imask |= mask;
269 	ethoc_write(dev, INT_MASK, imask);
270 }
271 
272 static inline void ethoc_disable_irq(struct ethoc *dev, u32 mask)
273 {
274 	u32 imask = ethoc_read(dev, INT_MASK);
275 	imask &= ~mask;
276 	ethoc_write(dev, INT_MASK, imask);
277 }
278 
279 static inline void ethoc_ack_irq(struct ethoc *dev, u32 mask)
280 {
281 	ethoc_write(dev, INT_SOURCE, mask);
282 }
283 
284 static inline void ethoc_enable_rx_and_tx(struct ethoc *dev)
285 {
286 	u32 mode = ethoc_read(dev, MODER);
287 	mode |= MODER_RXEN | MODER_TXEN;
288 	ethoc_write(dev, MODER, mode);
289 }
290 
291 static inline void ethoc_disable_rx_and_tx(struct ethoc *dev)
292 {
293 	u32 mode = ethoc_read(dev, MODER);
294 	mode &= ~(MODER_RXEN | MODER_TXEN);
295 	ethoc_write(dev, MODER, mode);
296 }
297 
298 static int ethoc_init_ring(struct ethoc *dev, unsigned long mem_start)
299 {
300 	struct ethoc_bd bd;
301 	int i;
302 	void *vma;
303 
304 	dev->cur_tx = 0;
305 	dev->dty_tx = 0;
306 	dev->cur_rx = 0;
307 
308 	ethoc_write(dev, TX_BD_NUM, dev->num_tx);
309 
310 	/* setup transmission buffers */
311 	bd.addr = mem_start;
312 	bd.stat = TX_BD_IRQ | TX_BD_CRC;
313 	vma = dev->membase;
314 
315 	for (i = 0; i < dev->num_tx; i++) {
316 		if (i == dev->num_tx - 1)
317 			bd.stat |= TX_BD_WRAP;
318 
319 		ethoc_write_bd(dev, i, &bd);
320 		bd.addr += ETHOC_BUFSIZ;
321 
322 		dev->vma[i] = vma;
323 		vma += ETHOC_BUFSIZ;
324 	}
325 
326 	bd.stat = RX_BD_EMPTY | RX_BD_IRQ;
327 
328 	for (i = 0; i < dev->num_rx; i++) {
329 		if (i == dev->num_rx - 1)
330 			bd.stat |= RX_BD_WRAP;
331 
332 		ethoc_write_bd(dev, dev->num_tx + i, &bd);
333 		bd.addr += ETHOC_BUFSIZ;
334 
335 		dev->vma[dev->num_tx + i] = vma;
336 		vma += ETHOC_BUFSIZ;
337 	}
338 
339 	return 0;
340 }
341 
342 static int ethoc_reset(struct ethoc *dev)
343 {
344 	u32 mode;
345 
346 	/* TODO: reset controller? */
347 
348 	ethoc_disable_rx_and_tx(dev);
349 
350 	/* TODO: setup registers */
351 
352 	/* enable FCS generation and automatic padding */
353 	mode = ethoc_read(dev, MODER);
354 	mode |= MODER_CRC | MODER_PAD;
355 	ethoc_write(dev, MODER, mode);
356 
357 	/* set full-duplex mode */
358 	mode = ethoc_read(dev, MODER);
359 	mode |= MODER_FULLD;
360 	ethoc_write(dev, MODER, mode);
361 	ethoc_write(dev, IPGT, 0x15);
362 
363 	ethoc_ack_irq(dev, INT_MASK_ALL);
364 	ethoc_enable_irq(dev, INT_MASK_ALL);
365 	ethoc_enable_rx_and_tx(dev);
366 	return 0;
367 }
368 
369 static unsigned int ethoc_update_rx_stats(struct ethoc *dev,
370 		struct ethoc_bd *bd)
371 {
372 	struct net_device *netdev = dev->netdev;
373 	unsigned int ret = 0;
374 
375 	if (bd->stat & RX_BD_TL) {
376 		dev_err(&netdev->dev, "RX: frame too long\n");
377 		netdev->stats.rx_length_errors++;
378 		ret++;
379 	}
380 
381 	if (bd->stat & RX_BD_SF) {
382 		dev_err(&netdev->dev, "RX: frame too short\n");
383 		netdev->stats.rx_length_errors++;
384 		ret++;
385 	}
386 
387 	if (bd->stat & RX_BD_DN) {
388 		dev_err(&netdev->dev, "RX: dribble nibble\n");
389 		netdev->stats.rx_frame_errors++;
390 	}
391 
392 	if (bd->stat & RX_BD_CRC) {
393 		dev_err(&netdev->dev, "RX: wrong CRC\n");
394 		netdev->stats.rx_crc_errors++;
395 		ret++;
396 	}
397 
398 	if (bd->stat & RX_BD_OR) {
399 		dev_err(&netdev->dev, "RX: overrun\n");
400 		netdev->stats.rx_over_errors++;
401 		ret++;
402 	}
403 
404 	if (bd->stat & RX_BD_MISS)
405 		netdev->stats.rx_missed_errors++;
406 
407 	if (bd->stat & RX_BD_LC) {
408 		dev_err(&netdev->dev, "RX: late collision\n");
409 		netdev->stats.collisions++;
410 		ret++;
411 	}
412 
413 	return ret;
414 }
415 
416 static int ethoc_rx(struct net_device *dev, int limit)
417 {
418 	struct ethoc *priv = netdev_priv(dev);
419 	int count;
420 
421 	for (count = 0; count < limit; ++count) {
422 		unsigned int entry;
423 		struct ethoc_bd bd;
424 
425 		entry = priv->num_tx + priv->cur_rx;
426 		ethoc_read_bd(priv, entry, &bd);
427 		if (bd.stat & RX_BD_EMPTY) {
428 			ethoc_ack_irq(priv, INT_MASK_RX);
429 			/* If packet (interrupt) came in between checking
430 			 * BD_EMTPY and clearing the interrupt source, then we
431 			 * risk missing the packet as the RX interrupt won't
432 			 * trigger right away when we reenable it; hence, check
433 			 * BD_EMTPY here again to make sure there isn't such a
434 			 * packet waiting for us...
435 			 */
436 			ethoc_read_bd(priv, entry, &bd);
437 			if (bd.stat & RX_BD_EMPTY)
438 				break;
439 		}
440 
441 		if (ethoc_update_rx_stats(priv, &bd) == 0) {
442 			int size = bd.stat >> 16;
443 			struct sk_buff *skb;
444 
445 			size -= 4; /* strip the CRC */
446 			skb = netdev_alloc_skb_ip_align(dev, size);
447 
448 			if (likely(skb)) {
449 				void *src = priv->vma[entry];
450 				memcpy_fromio(skb_put(skb, size), src, size);
451 				skb->protocol = eth_type_trans(skb, dev);
452 				dev->stats.rx_packets++;
453 				dev->stats.rx_bytes += size;
454 				netif_receive_skb(skb);
455 			} else {
456 				if (net_ratelimit())
457 					dev_warn(&dev->dev,
458 					    "low on memory - packet dropped\n");
459 
460 				dev->stats.rx_dropped++;
461 				break;
462 			}
463 		}
464 
465 		/* clear the buffer descriptor so it can be reused */
466 		bd.stat &= ~RX_BD_STATS;
467 		bd.stat |=  RX_BD_EMPTY;
468 		ethoc_write_bd(priv, entry, &bd);
469 		if (++priv->cur_rx == priv->num_rx)
470 			priv->cur_rx = 0;
471 	}
472 
473 	return count;
474 }
475 
476 static void ethoc_update_tx_stats(struct ethoc *dev, struct ethoc_bd *bd)
477 {
478 	struct net_device *netdev = dev->netdev;
479 
480 	if (bd->stat & TX_BD_LC) {
481 		dev_err(&netdev->dev, "TX: late collision\n");
482 		netdev->stats.tx_window_errors++;
483 	}
484 
485 	if (bd->stat & TX_BD_RL) {
486 		dev_err(&netdev->dev, "TX: retransmit limit\n");
487 		netdev->stats.tx_aborted_errors++;
488 	}
489 
490 	if (bd->stat & TX_BD_UR) {
491 		dev_err(&netdev->dev, "TX: underrun\n");
492 		netdev->stats.tx_fifo_errors++;
493 	}
494 
495 	if (bd->stat & TX_BD_CS) {
496 		dev_err(&netdev->dev, "TX: carrier sense lost\n");
497 		netdev->stats.tx_carrier_errors++;
498 	}
499 
500 	if (bd->stat & TX_BD_STATS)
501 		netdev->stats.tx_errors++;
502 
503 	netdev->stats.collisions += (bd->stat >> 4) & 0xf;
504 	netdev->stats.tx_bytes += bd->stat >> 16;
505 	netdev->stats.tx_packets++;
506 }
507 
508 static int ethoc_tx(struct net_device *dev, int limit)
509 {
510 	struct ethoc *priv = netdev_priv(dev);
511 	int count;
512 	struct ethoc_bd bd;
513 
514 	for (count = 0; count < limit; ++count) {
515 		unsigned int entry;
516 
517 		entry = priv->dty_tx & (priv->num_tx-1);
518 
519 		ethoc_read_bd(priv, entry, &bd);
520 
521 		if (bd.stat & TX_BD_READY || (priv->dty_tx == priv->cur_tx)) {
522 			ethoc_ack_irq(priv, INT_MASK_TX);
523 			/* If interrupt came in between reading in the BD
524 			 * and clearing the interrupt source, then we risk
525 			 * missing the event as the TX interrupt won't trigger
526 			 * right away when we reenable it; hence, check
527 			 * BD_EMPTY here again to make sure there isn't such an
528 			 * event pending...
529 			 */
530 			ethoc_read_bd(priv, entry, &bd);
531 			if (bd.stat & TX_BD_READY ||
532 			    (priv->dty_tx == priv->cur_tx))
533 				break;
534 		}
535 
536 		ethoc_update_tx_stats(priv, &bd);
537 		priv->dty_tx++;
538 	}
539 
540 	if ((priv->cur_tx - priv->dty_tx) <= (priv->num_tx / 2))
541 		netif_wake_queue(dev);
542 
543 	return count;
544 }
545 
546 static irqreturn_t ethoc_interrupt(int irq, void *dev_id)
547 {
548 	struct net_device *dev = dev_id;
549 	struct ethoc *priv = netdev_priv(dev);
550 	u32 pending;
551 	u32 mask;
552 
553 	/* Figure out what triggered the interrupt...
554 	 * The tricky bit here is that the interrupt source bits get
555 	 * set in INT_SOURCE for an event regardless of whether that
556 	 * event is masked or not.  Thus, in order to figure out what
557 	 * triggered the interrupt, we need to remove the sources
558 	 * for all events that are currently masked.  This behaviour
559 	 * is not particularly well documented but reasonable...
560 	 */
561 	mask = ethoc_read(priv, INT_MASK);
562 	pending = ethoc_read(priv, INT_SOURCE);
563 	pending &= mask;
564 
565 	if (unlikely(pending == 0))
566 		return IRQ_NONE;
567 
568 	ethoc_ack_irq(priv, pending);
569 
570 	/* We always handle the dropped packet interrupt */
571 	if (pending & INT_MASK_BUSY) {
572 		dev_dbg(&dev->dev, "packet dropped\n");
573 		dev->stats.rx_dropped++;
574 	}
575 
576 	/* Handle receive/transmit event by switching to polling */
577 	if (pending & (INT_MASK_TX | INT_MASK_RX)) {
578 		ethoc_disable_irq(priv, INT_MASK_TX | INT_MASK_RX);
579 		napi_schedule(&priv->napi);
580 	}
581 
582 	return IRQ_HANDLED;
583 }
584 
585 static int ethoc_get_mac_address(struct net_device *dev, void *addr)
586 {
587 	struct ethoc *priv = netdev_priv(dev);
588 	u8 *mac = (u8 *)addr;
589 	u32 reg;
590 
591 	reg = ethoc_read(priv, MAC_ADDR0);
592 	mac[2] = (reg >> 24) & 0xff;
593 	mac[3] = (reg >> 16) & 0xff;
594 	mac[4] = (reg >>  8) & 0xff;
595 	mac[5] = (reg >>  0) & 0xff;
596 
597 	reg = ethoc_read(priv, MAC_ADDR1);
598 	mac[0] = (reg >>  8) & 0xff;
599 	mac[1] = (reg >>  0) & 0xff;
600 
601 	return 0;
602 }
603 
604 static int ethoc_poll(struct napi_struct *napi, int budget)
605 {
606 	struct ethoc *priv = container_of(napi, struct ethoc, napi);
607 	int rx_work_done = 0;
608 	int tx_work_done = 0;
609 
610 	rx_work_done = ethoc_rx(priv->netdev, budget);
611 	tx_work_done = ethoc_tx(priv->netdev, budget);
612 
613 	if (rx_work_done < budget && tx_work_done < budget) {
614 		napi_complete_done(napi, rx_work_done);
615 		ethoc_enable_irq(priv, INT_MASK_TX | INT_MASK_RX);
616 	}
617 
618 	return rx_work_done;
619 }
620 
621 static int ethoc_mdio_read(struct mii_bus *bus, int phy, int reg)
622 {
623 	struct ethoc *priv = bus->priv;
624 	int i;
625 
626 	ethoc_write(priv, MIIADDRESS, MIIADDRESS_ADDR(phy, reg));
627 	ethoc_write(priv, MIICOMMAND, MIICOMMAND_READ);
628 
629 	for (i = 0; i < 5; i++) {
630 		u32 status = ethoc_read(priv, MIISTATUS);
631 		if (!(status & MIISTATUS_BUSY)) {
632 			u32 data = ethoc_read(priv, MIIRX_DATA);
633 			/* reset MII command register */
634 			ethoc_write(priv, MIICOMMAND, 0);
635 			return data;
636 		}
637 		usleep_range(100, 200);
638 	}
639 
640 	return -EBUSY;
641 }
642 
643 static int ethoc_mdio_write(struct mii_bus *bus, int phy, int reg, u16 val)
644 {
645 	struct ethoc *priv = bus->priv;
646 	int i;
647 
648 	ethoc_write(priv, MIIADDRESS, MIIADDRESS_ADDR(phy, reg));
649 	ethoc_write(priv, MIITX_DATA, val);
650 	ethoc_write(priv, MIICOMMAND, MIICOMMAND_WRITE);
651 
652 	for (i = 0; i < 5; i++) {
653 		u32 stat = ethoc_read(priv, MIISTATUS);
654 		if (!(stat & MIISTATUS_BUSY)) {
655 			/* reset MII command register */
656 			ethoc_write(priv, MIICOMMAND, 0);
657 			return 0;
658 		}
659 		usleep_range(100, 200);
660 	}
661 
662 	return -EBUSY;
663 }
664 
665 static void ethoc_mdio_poll(struct net_device *dev)
666 {
667 	struct ethoc *priv = netdev_priv(dev);
668 	struct phy_device *phydev = dev->phydev;
669 	bool changed = false;
670 	u32 mode;
671 
672 	if (priv->old_link != phydev->link) {
673 		changed = true;
674 		priv->old_link = phydev->link;
675 	}
676 
677 	if (priv->old_duplex != phydev->duplex) {
678 		changed = true;
679 		priv->old_duplex = phydev->duplex;
680 	}
681 
682 	if (!changed)
683 		return;
684 
685 	mode = ethoc_read(priv, MODER);
686 	if (phydev->duplex == DUPLEX_FULL)
687 		mode |= MODER_FULLD;
688 	else
689 		mode &= ~MODER_FULLD;
690 	ethoc_write(priv, MODER, mode);
691 
692 	phy_print_status(phydev);
693 }
694 
695 static int ethoc_mdio_probe(struct net_device *dev)
696 {
697 	struct ethoc *priv = netdev_priv(dev);
698 	struct phy_device *phy;
699 	int err;
700 
701 	if (priv->phy_id != -1)
702 		phy = mdiobus_get_phy(priv->mdio, priv->phy_id);
703 	else
704 		phy = phy_find_first(priv->mdio);
705 
706 	if (!phy) {
707 		dev_err(&dev->dev, "no PHY found\n");
708 		return -ENXIO;
709 	}
710 
711 	priv->old_duplex = -1;
712 	priv->old_link = -1;
713 
714 	err = phy_connect_direct(dev, phy, ethoc_mdio_poll,
715 				 PHY_INTERFACE_MODE_GMII);
716 	if (err) {
717 		dev_err(&dev->dev, "could not attach to PHY\n");
718 		return err;
719 	}
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 	struct ethoc *priv = netdev_priv(dev);
806 	unsigned char *mac = dev->dev_addr;
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 	memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
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 {
950 	struct ethoc *priv = netdev_priv(dev);
951 
952 	ring->rx_max_pending = priv->num_bd - 1;
953 	ring->rx_mini_max_pending = 0;
954 	ring->rx_jumbo_max_pending = 0;
955 	ring->tx_max_pending = priv->num_bd - 1;
956 
957 	ring->rx_pending = priv->num_rx;
958 	ring->rx_mini_pending = 0;
959 	ring->rx_jumbo_pending = 0;
960 	ring->tx_pending = priv->num_tx;
961 }
962 
963 static int ethoc_set_ringparam(struct net_device *dev,
964 			       struct ethtool_ringparam *ring)
965 {
966 	struct ethoc *priv = netdev_priv(dev);
967 
968 	if (ring->tx_pending < 1 || ring->rx_pending < 1 ||
969 	    ring->tx_pending + ring->rx_pending > priv->num_bd)
970 		return -EINVAL;
971 	if (ring->rx_mini_pending || ring->rx_jumbo_pending)
972 		return -EINVAL;
973 
974 	if (netif_running(dev)) {
975 		netif_tx_disable(dev);
976 		ethoc_disable_rx_and_tx(priv);
977 		ethoc_disable_irq(priv, INT_MASK_TX | INT_MASK_RX);
978 		synchronize_irq(dev->irq);
979 	}
980 
981 	priv->num_tx = rounddown_pow_of_two(ring->tx_pending);
982 	priv->num_rx = ring->rx_pending;
983 	ethoc_init_ring(priv, dev->mem_start);
984 
985 	if (netif_running(dev)) {
986 		ethoc_enable_irq(priv, INT_MASK_TX | INT_MASK_RX);
987 		ethoc_enable_rx_and_tx(priv);
988 		netif_wake_queue(dev);
989 	}
990 	return 0;
991 }
992 
993 static const struct ethtool_ops ethoc_ethtool_ops = {
994 	.get_regs_len = ethoc_get_regs_len,
995 	.get_regs = ethoc_get_regs,
996 	.nway_reset = phy_ethtool_nway_reset,
997 	.get_link = ethtool_op_get_link,
998 	.get_ringparam = ethoc_get_ringparam,
999 	.set_ringparam = ethoc_set_ringparam,
1000 	.get_ts_info = ethtool_op_get_ts_info,
1001 	.get_link_ksettings = phy_ethtool_get_link_ksettings,
1002 	.set_link_ksettings = phy_ethtool_set_link_ksettings,
1003 };
1004 
1005 static const struct net_device_ops ethoc_netdev_ops = {
1006 	.ndo_open = ethoc_open,
1007 	.ndo_stop = ethoc_stop,
1008 	.ndo_do_ioctl = ethoc_ioctl,
1009 	.ndo_set_mac_address = ethoc_set_mac_address,
1010 	.ndo_set_rx_mode = ethoc_set_multicast_list,
1011 	.ndo_change_mtu = ethoc_change_mtu,
1012 	.ndo_tx_timeout = ethoc_tx_timeout,
1013 	.ndo_start_xmit = ethoc_start_xmit,
1014 };
1015 
1016 /**
1017  * ethoc_probe - initialize OpenCores ethernet MAC
1018  * pdev:	platform device
1019  */
1020 static int ethoc_probe(struct platform_device *pdev)
1021 {
1022 	struct net_device *netdev = NULL;
1023 	struct resource *res = NULL;
1024 	struct resource *mmio = NULL;
1025 	struct resource *mem = NULL;
1026 	struct ethoc *priv = NULL;
1027 	int num_bd;
1028 	int ret = 0;
1029 	struct ethoc_platform_data *pdata = dev_get_platdata(&pdev->dev);
1030 	u32 eth_clkfreq = pdata ? pdata->eth_clkfreq : 0;
1031 
1032 	/* allocate networking device */
1033 	netdev = alloc_etherdev(sizeof(struct ethoc));
1034 	if (!netdev) {
1035 		ret = -ENOMEM;
1036 		goto out;
1037 	}
1038 
1039 	SET_NETDEV_DEV(netdev, &pdev->dev);
1040 	platform_set_drvdata(pdev, netdev);
1041 
1042 	/* obtain I/O memory space */
1043 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1044 	if (!res) {
1045 		dev_err(&pdev->dev, "cannot obtain I/O memory space\n");
1046 		ret = -ENXIO;
1047 		goto free;
1048 	}
1049 
1050 	mmio = devm_request_mem_region(&pdev->dev, res->start,
1051 			resource_size(res), res->name);
1052 	if (!mmio) {
1053 		dev_err(&pdev->dev, "cannot request I/O memory space\n");
1054 		ret = -ENXIO;
1055 		goto free;
1056 	}
1057 
1058 	netdev->base_addr = mmio->start;
1059 
1060 	/* obtain buffer memory space */
1061 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1062 	if (res) {
1063 		mem = devm_request_mem_region(&pdev->dev, res->start,
1064 			resource_size(res), res->name);
1065 		if (!mem) {
1066 			dev_err(&pdev->dev, "cannot request memory space\n");
1067 			ret = -ENXIO;
1068 			goto free;
1069 		}
1070 
1071 		netdev->mem_start = mem->start;
1072 		netdev->mem_end   = mem->end;
1073 	}
1074 
1075 
1076 	/* obtain device IRQ number */
1077 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1078 	if (!res) {
1079 		dev_err(&pdev->dev, "cannot obtain IRQ\n");
1080 		ret = -ENXIO;
1081 		goto free;
1082 	}
1083 
1084 	netdev->irq = res->start;
1085 
1086 	/* setup driver-private data */
1087 	priv = netdev_priv(netdev);
1088 	priv->netdev = netdev;
1089 
1090 	priv->iobase = devm_ioremap(&pdev->dev, netdev->base_addr,
1091 			resource_size(mmio));
1092 	if (!priv->iobase) {
1093 		dev_err(&pdev->dev, "cannot remap I/O memory space\n");
1094 		ret = -ENXIO;
1095 		goto free;
1096 	}
1097 
1098 	if (netdev->mem_end) {
1099 		priv->membase = devm_ioremap(&pdev->dev,
1100 			netdev->mem_start, resource_size(mem));
1101 		if (!priv->membase) {
1102 			dev_err(&pdev->dev, "cannot remap memory space\n");
1103 			ret = -ENXIO;
1104 			goto free;
1105 		}
1106 	} else {
1107 		/* Allocate buffer memory */
1108 		priv->membase = dmam_alloc_coherent(&pdev->dev,
1109 			buffer_size, (void *)&netdev->mem_start,
1110 			GFP_KERNEL);
1111 		if (!priv->membase) {
1112 			dev_err(&pdev->dev, "cannot allocate %dB buffer\n",
1113 				buffer_size);
1114 			ret = -ENOMEM;
1115 			goto free;
1116 		}
1117 		netdev->mem_end = netdev->mem_start + buffer_size;
1118 	}
1119 
1120 	priv->big_endian = pdata ? pdata->big_endian :
1121 		of_device_is_big_endian(pdev->dev.of_node);
1122 
1123 	/* calculate the number of TX/RX buffers, maximum 128 supported */
1124 	num_bd = min_t(unsigned int,
1125 		128, (netdev->mem_end - netdev->mem_start + 1) / ETHOC_BUFSIZ);
1126 	if (num_bd < 4) {
1127 		ret = -ENODEV;
1128 		goto free;
1129 	}
1130 	priv->num_bd = num_bd;
1131 	/* num_tx must be a power of two */
1132 	priv->num_tx = rounddown_pow_of_two(num_bd >> 1);
1133 	priv->num_rx = num_bd - priv->num_tx;
1134 
1135 	dev_dbg(&pdev->dev, "ethoc: num_tx: %d num_rx: %d\n",
1136 		priv->num_tx, priv->num_rx);
1137 
1138 	priv->vma = devm_kcalloc(&pdev->dev, num_bd, sizeof(void *),
1139 				 GFP_KERNEL);
1140 	if (!priv->vma) {
1141 		ret = -ENOMEM;
1142 		goto free;
1143 	}
1144 
1145 	/* Allow the platform setup code to pass in a MAC address. */
1146 	if (pdata) {
1147 		ether_addr_copy(netdev->dev_addr, pdata->hwaddr);
1148 		priv->phy_id = pdata->phy_id;
1149 	} else {
1150 		const void *mac;
1151 
1152 		mac = of_get_mac_address(pdev->dev.of_node);
1153 		if (!IS_ERR(mac))
1154 			ether_addr_copy(netdev->dev_addr, mac);
1155 		priv->phy_id = -1;
1156 	}
1157 
1158 	/* Check that the given MAC address is valid. If it isn't, read the
1159 	 * current MAC from the controller.
1160 	 */
1161 	if (!is_valid_ether_addr(netdev->dev_addr))
1162 		ethoc_get_mac_address(netdev, netdev->dev_addr);
1163 
1164 	/* Check the MAC again for validity, if it still isn't choose and
1165 	 * program a random one.
1166 	 */
1167 	if (!is_valid_ether_addr(netdev->dev_addr))
1168 		eth_hw_addr_random(netdev);
1169 
1170 	ethoc_do_set_mac_address(netdev);
1171 
1172 	/* Allow the platform setup code to adjust MII management bus clock. */
1173 	if (!eth_clkfreq) {
1174 		struct clk *clk = devm_clk_get(&pdev->dev, NULL);
1175 
1176 		if (!IS_ERR(clk)) {
1177 			priv->clk = clk;
1178 			clk_prepare_enable(clk);
1179 			eth_clkfreq = clk_get_rate(clk);
1180 		}
1181 	}
1182 	if (eth_clkfreq) {
1183 		u32 clkdiv = MIIMODER_CLKDIV(eth_clkfreq / 2500000 + 1);
1184 
1185 		if (!clkdiv)
1186 			clkdiv = 2;
1187 		dev_dbg(&pdev->dev, "setting MII clkdiv to %u\n", clkdiv);
1188 		ethoc_write(priv, MIIMODER,
1189 			    (ethoc_read(priv, MIIMODER) & MIIMODER_NOPRE) |
1190 			    clkdiv);
1191 	}
1192 
1193 	/* register MII bus */
1194 	priv->mdio = mdiobus_alloc();
1195 	if (!priv->mdio) {
1196 		ret = -ENOMEM;
1197 		goto free2;
1198 	}
1199 
1200 	priv->mdio->name = "ethoc-mdio";
1201 	snprintf(priv->mdio->id, MII_BUS_ID_SIZE, "%s-%d",
1202 			priv->mdio->name, pdev->id);
1203 	priv->mdio->read = ethoc_mdio_read;
1204 	priv->mdio->write = ethoc_mdio_write;
1205 	priv->mdio->priv = priv;
1206 
1207 	ret = mdiobus_register(priv->mdio);
1208 	if (ret) {
1209 		dev_err(&netdev->dev, "failed to register MDIO bus\n");
1210 		goto free2;
1211 	}
1212 
1213 	ret = ethoc_mdio_probe(netdev);
1214 	if (ret) {
1215 		dev_err(&netdev->dev, "failed to probe MDIO bus\n");
1216 		goto error;
1217 	}
1218 
1219 	/* setup the net_device structure */
1220 	netdev->netdev_ops = &ethoc_netdev_ops;
1221 	netdev->watchdog_timeo = ETHOC_TIMEOUT;
1222 	netdev->features |= 0;
1223 	netdev->ethtool_ops = &ethoc_ethtool_ops;
1224 
1225 	/* setup NAPI */
1226 	netif_napi_add(netdev, &priv->napi, ethoc_poll, 64);
1227 
1228 	spin_lock_init(&priv->lock);
1229 
1230 	ret = register_netdev(netdev);
1231 	if (ret < 0) {
1232 		dev_err(&netdev->dev, "failed to register interface\n");
1233 		goto error2;
1234 	}
1235 
1236 	goto out;
1237 
1238 error2:
1239 	netif_napi_del(&priv->napi);
1240 error:
1241 	mdiobus_unregister(priv->mdio);
1242 	mdiobus_free(priv->mdio);
1243 free2:
1244 	clk_disable_unprepare(priv->clk);
1245 free:
1246 	free_netdev(netdev);
1247 out:
1248 	return ret;
1249 }
1250 
1251 /**
1252  * ethoc_remove - shutdown OpenCores ethernet MAC
1253  * @pdev:	platform device
1254  */
1255 static int ethoc_remove(struct platform_device *pdev)
1256 {
1257 	struct net_device *netdev = platform_get_drvdata(pdev);
1258 	struct ethoc *priv = netdev_priv(netdev);
1259 
1260 	if (netdev) {
1261 		netif_napi_del(&priv->napi);
1262 		phy_disconnect(netdev->phydev);
1263 
1264 		if (priv->mdio) {
1265 			mdiobus_unregister(priv->mdio);
1266 			mdiobus_free(priv->mdio);
1267 		}
1268 		clk_disable_unprepare(priv->clk);
1269 		unregister_netdev(netdev);
1270 		free_netdev(netdev);
1271 	}
1272 
1273 	return 0;
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