xref: /openbmc/linux/drivers/net/ethernet/ethoc.c (revision bc5aa3a0)
1 /*
2  * linux/drivers/net/ethernet/ethoc.c
3  *
4  * Copyright (C) 2007-2008 Avionic Design Development GmbH
5  * Copyright (C) 2008-2009 Avionic Design GmbH
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License version 2 as
9  * published by the Free Software Foundation.
10  *
11  * Written by Thierry Reding <thierry.reding@avionic-design.de>
12  */
13 
14 #include <linux/dma-mapping.h>
15 #include <linux/etherdevice.h>
16 #include <linux/clk.h>
17 #include <linux/crc32.h>
18 #include <linux/interrupt.h>
19 #include <linux/io.h>
20 #include <linux/mii.h>
21 #include <linux/phy.h>
22 #include <linux/platform_device.h>
23 #include <linux/sched.h>
24 #include <linux/slab.h>
25 #include <linux/of.h>
26 #include <linux/module.h>
27 #include <net/ethoc.h>
28 
29 static int buffer_size = 0x8000; /* 32 KBytes */
30 module_param(buffer_size, int, 0);
31 MODULE_PARM_DESC(buffer_size, "DMA buffer allocation size");
32 
33 /* register offsets */
34 #define	MODER		0x00
35 #define	INT_SOURCE	0x04
36 #define	INT_MASK	0x08
37 #define	IPGT		0x0c
38 #define	IPGR1		0x10
39 #define	IPGR2		0x14
40 #define	PACKETLEN	0x18
41 #define	COLLCONF	0x1c
42 #define	TX_BD_NUM	0x20
43 #define	CTRLMODER	0x24
44 #define	MIIMODER	0x28
45 #define	MIICOMMAND	0x2c
46 #define	MIIADDRESS	0x30
47 #define	MIITX_DATA	0x34
48 #define	MIIRX_DATA	0x38
49 #define	MIISTATUS	0x3c
50 #define	MAC_ADDR0	0x40
51 #define	MAC_ADDR1	0x44
52 #define	ETH_HASH0	0x48
53 #define	ETH_HASH1	0x4c
54 #define	ETH_TXCTRL	0x50
55 #define	ETH_END		0x54
56 
57 /* mode register */
58 #define	MODER_RXEN	(1 <<  0) /* receive enable */
59 #define	MODER_TXEN	(1 <<  1) /* transmit enable */
60 #define	MODER_NOPRE	(1 <<  2) /* no preamble */
61 #define	MODER_BRO	(1 <<  3) /* broadcast address */
62 #define	MODER_IAM	(1 <<  4) /* individual address mode */
63 #define	MODER_PRO	(1 <<  5) /* promiscuous mode */
64 #define	MODER_IFG	(1 <<  6) /* interframe gap for incoming frames */
65 #define	MODER_LOOP	(1 <<  7) /* loopback */
66 #define	MODER_NBO	(1 <<  8) /* no back-off */
67 #define	MODER_EDE	(1 <<  9) /* excess defer enable */
68 #define	MODER_FULLD	(1 << 10) /* full duplex */
69 #define	MODER_RESET	(1 << 11) /* FIXME: reset (undocumented) */
70 #define	MODER_DCRC	(1 << 12) /* delayed CRC enable */
71 #define	MODER_CRC	(1 << 13) /* CRC enable */
72 #define	MODER_HUGE	(1 << 14) /* huge packets enable */
73 #define	MODER_PAD	(1 << 15) /* padding enabled */
74 #define	MODER_RSM	(1 << 16) /* receive small packets */
75 
76 /* interrupt source and mask registers */
77 #define	INT_MASK_TXF	(1 << 0) /* transmit frame */
78 #define	INT_MASK_TXE	(1 << 1) /* transmit error */
79 #define	INT_MASK_RXF	(1 << 2) /* receive frame */
80 #define	INT_MASK_RXE	(1 << 3) /* receive error */
81 #define	INT_MASK_BUSY	(1 << 4)
82 #define	INT_MASK_TXC	(1 << 5) /* transmit control frame */
83 #define	INT_MASK_RXC	(1 << 6) /* receive control frame */
84 
85 #define	INT_MASK_TX	(INT_MASK_TXF | INT_MASK_TXE)
86 #define	INT_MASK_RX	(INT_MASK_RXF | INT_MASK_RXE)
87 
88 #define	INT_MASK_ALL ( \
89 		INT_MASK_TXF | INT_MASK_TXE | \
90 		INT_MASK_RXF | INT_MASK_RXE | \
91 		INT_MASK_TXC | INT_MASK_RXC | \
92 		INT_MASK_BUSY \
93 	)
94 
95 /* packet length register */
96 #define	PACKETLEN_MIN(min)		(((min) & 0xffff) << 16)
97 #define	PACKETLEN_MAX(max)		(((max) & 0xffff) <<  0)
98 #define	PACKETLEN_MIN_MAX(min, max)	(PACKETLEN_MIN(min) | \
99 					PACKETLEN_MAX(max))
100 
101 /* transmit buffer number register */
102 #define	TX_BD_NUM_VAL(x)	(((x) <= 0x80) ? (x) : 0x80)
103 
104 /* control module mode register */
105 #define	CTRLMODER_PASSALL	(1 << 0) /* pass all receive frames */
106 #define	CTRLMODER_RXFLOW	(1 << 1) /* receive control flow */
107 #define	CTRLMODER_TXFLOW	(1 << 2) /* transmit control flow */
108 
109 /* MII mode register */
110 #define	MIIMODER_CLKDIV(x)	((x) & 0xfe) /* needs to be an even number */
111 #define	MIIMODER_NOPRE		(1 << 8) /* no preamble */
112 
113 /* MII command register */
114 #define	MIICOMMAND_SCAN		(1 << 0) /* scan status */
115 #define	MIICOMMAND_READ		(1 << 1) /* read status */
116 #define	MIICOMMAND_WRITE	(1 << 2) /* write control data */
117 
118 /* MII address register */
119 #define	MIIADDRESS_FIAD(x)		(((x) & 0x1f) << 0)
120 #define	MIIADDRESS_RGAD(x)		(((x) & 0x1f) << 8)
121 #define	MIIADDRESS_ADDR(phy, reg)	(MIIADDRESS_FIAD(phy) | \
122 					MIIADDRESS_RGAD(reg))
123 
124 /* MII transmit data register */
125 #define	MIITX_DATA_VAL(x)	((x) & 0xffff)
126 
127 /* MII receive data register */
128 #define	MIIRX_DATA_VAL(x)	((x) & 0xffff)
129 
130 /* MII status register */
131 #define	MIISTATUS_LINKFAIL	(1 << 0)
132 #define	MIISTATUS_BUSY		(1 << 1)
133 #define	MIISTATUS_INVALID	(1 << 2)
134 
135 /* TX buffer descriptor */
136 #define	TX_BD_CS		(1 <<  0) /* carrier sense lost */
137 #define	TX_BD_DF		(1 <<  1) /* defer indication */
138 #define	TX_BD_LC		(1 <<  2) /* late collision */
139 #define	TX_BD_RL		(1 <<  3) /* retransmission limit */
140 #define	TX_BD_RETRY_MASK	(0x00f0)
141 #define	TX_BD_RETRY(x)		(((x) & 0x00f0) >>  4)
142 #define	TX_BD_UR		(1 <<  8) /* transmitter underrun */
143 #define	TX_BD_CRC		(1 << 11) /* TX CRC enable */
144 #define	TX_BD_PAD		(1 << 12) /* pad enable for short packets */
145 #define	TX_BD_WRAP		(1 << 13)
146 #define	TX_BD_IRQ		(1 << 14) /* interrupt request enable */
147 #define	TX_BD_READY		(1 << 15) /* TX buffer ready */
148 #define	TX_BD_LEN(x)		(((x) & 0xffff) << 16)
149 #define	TX_BD_LEN_MASK		(0xffff << 16)
150 
151 #define	TX_BD_STATS		(TX_BD_CS | TX_BD_DF | TX_BD_LC | \
152 				TX_BD_RL | TX_BD_RETRY_MASK | TX_BD_UR)
153 
154 /* RX buffer descriptor */
155 #define	RX_BD_LC	(1 <<  0) /* late collision */
156 #define	RX_BD_CRC	(1 <<  1) /* RX CRC error */
157 #define	RX_BD_SF	(1 <<  2) /* short frame */
158 #define	RX_BD_TL	(1 <<  3) /* too long */
159 #define	RX_BD_DN	(1 <<  4) /* dribble nibble */
160 #define	RX_BD_IS	(1 <<  5) /* invalid symbol */
161 #define	RX_BD_OR	(1 <<  6) /* receiver overrun */
162 #define	RX_BD_MISS	(1 <<  7)
163 #define	RX_BD_CF	(1 <<  8) /* control frame */
164 #define	RX_BD_WRAP	(1 << 13)
165 #define	RX_BD_IRQ	(1 << 14) /* interrupt request enable */
166 #define	RX_BD_EMPTY	(1 << 15)
167 #define	RX_BD_LEN(x)	(((x) & 0xffff) << 16)
168 
169 #define	RX_BD_STATS	(RX_BD_LC | RX_BD_CRC | RX_BD_SF | RX_BD_TL | \
170 			RX_BD_DN | RX_BD_IS | RX_BD_OR | RX_BD_MISS)
171 
172 #define	ETHOC_BUFSIZ		1536
173 #define	ETHOC_ZLEN		64
174 #define	ETHOC_BD_BASE		0x400
175 #define	ETHOC_TIMEOUT		(HZ / 2)
176 #define	ETHOC_MII_TIMEOUT	(1 + (HZ / 5))
177 
178 /**
179  * struct ethoc - driver-private device structure
180  * @iobase:	pointer to I/O memory region
181  * @membase:	pointer to buffer memory region
182  * @dma_alloc:	dma allocated buffer size
183  * @io_region_size:	I/O memory region size
184  * @num_bd:	number of buffer descriptors
185  * @num_tx:	number of send buffers
186  * @cur_tx:	last send buffer written
187  * @dty_tx:	last buffer actually sent
188  * @num_rx:	number of receive buffers
189  * @cur_rx:	current receive buffer
190  * @vma:        pointer to array of virtual memory addresses for buffers
191  * @netdev:	pointer to network device structure
192  * @napi:	NAPI structure
193  * @msg_enable:	device state flags
194  * @lock:	device lock
195  * @mdio:	MDIO bus for PHY access
196  * @phy_id:	address of attached PHY
197  */
198 struct ethoc {
199 	void __iomem *iobase;
200 	void __iomem *membase;
201 	int dma_alloc;
202 	resource_size_t io_region_size;
203 	bool big_endian;
204 
205 	unsigned int num_bd;
206 	unsigned int num_tx;
207 	unsigned int cur_tx;
208 	unsigned int dty_tx;
209 
210 	unsigned int num_rx;
211 	unsigned int cur_rx;
212 
213 	void **vma;
214 
215 	struct net_device *netdev;
216 	struct napi_struct napi;
217 	u32 msg_enable;
218 
219 	spinlock_t lock;
220 
221 	struct mii_bus *mdio;
222 	struct clk *clk;
223 	s8 phy_id;
224 };
225 
226 /**
227  * struct ethoc_bd - buffer descriptor
228  * @stat:	buffer statistics
229  * @addr:	physical memory address
230  */
231 struct ethoc_bd {
232 	u32 stat;
233 	u32 addr;
234 };
235 
236 static inline u32 ethoc_read(struct ethoc *dev, loff_t offset)
237 {
238 	if (dev->big_endian)
239 		return ioread32be(dev->iobase + offset);
240 	else
241 		return ioread32(dev->iobase + offset);
242 }
243 
244 static inline void ethoc_write(struct ethoc *dev, loff_t offset, u32 data)
245 {
246 	if (dev->big_endian)
247 		iowrite32be(data, dev->iobase + offset);
248 	else
249 		iowrite32(data, dev->iobase + offset);
250 }
251 
252 static inline void ethoc_read_bd(struct ethoc *dev, int index,
253 		struct ethoc_bd *bd)
254 {
255 	loff_t offset = ETHOC_BD_BASE + (index * sizeof(struct ethoc_bd));
256 	bd->stat = ethoc_read(dev, offset + 0);
257 	bd->addr = ethoc_read(dev, offset + 4);
258 }
259 
260 static inline void ethoc_write_bd(struct ethoc *dev, int index,
261 		const struct ethoc_bd *bd)
262 {
263 	loff_t offset = ETHOC_BD_BASE + (index * sizeof(struct ethoc_bd));
264 	ethoc_write(dev, offset + 0, bd->stat);
265 	ethoc_write(dev, offset + 4, bd->addr);
266 }
267 
268 static inline void ethoc_enable_irq(struct ethoc *dev, u32 mask)
269 {
270 	u32 imask = ethoc_read(dev, INT_MASK);
271 	imask |= mask;
272 	ethoc_write(dev, INT_MASK, imask);
273 }
274 
275 static inline void ethoc_disable_irq(struct ethoc *dev, u32 mask)
276 {
277 	u32 imask = ethoc_read(dev, INT_MASK);
278 	imask &= ~mask;
279 	ethoc_write(dev, INT_MASK, imask);
280 }
281 
282 static inline void ethoc_ack_irq(struct ethoc *dev, u32 mask)
283 {
284 	ethoc_write(dev, INT_SOURCE, mask);
285 }
286 
287 static inline void ethoc_enable_rx_and_tx(struct ethoc *dev)
288 {
289 	u32 mode = ethoc_read(dev, MODER);
290 	mode |= MODER_RXEN | MODER_TXEN;
291 	ethoc_write(dev, MODER, mode);
292 }
293 
294 static inline void ethoc_disable_rx_and_tx(struct ethoc *dev)
295 {
296 	u32 mode = ethoc_read(dev, MODER);
297 	mode &= ~(MODER_RXEN | MODER_TXEN);
298 	ethoc_write(dev, MODER, mode);
299 }
300 
301 static int ethoc_init_ring(struct ethoc *dev, unsigned long mem_start)
302 {
303 	struct ethoc_bd bd;
304 	int i;
305 	void *vma;
306 
307 	dev->cur_tx = 0;
308 	dev->dty_tx = 0;
309 	dev->cur_rx = 0;
310 
311 	ethoc_write(dev, TX_BD_NUM, dev->num_tx);
312 
313 	/* setup transmission buffers */
314 	bd.addr = mem_start;
315 	bd.stat = TX_BD_IRQ | TX_BD_CRC;
316 	vma = dev->membase;
317 
318 	for (i = 0; i < dev->num_tx; i++) {
319 		if (i == dev->num_tx - 1)
320 			bd.stat |= TX_BD_WRAP;
321 
322 		ethoc_write_bd(dev, i, &bd);
323 		bd.addr += ETHOC_BUFSIZ;
324 
325 		dev->vma[i] = vma;
326 		vma += ETHOC_BUFSIZ;
327 	}
328 
329 	bd.stat = RX_BD_EMPTY | RX_BD_IRQ;
330 
331 	for (i = 0; i < dev->num_rx; i++) {
332 		if (i == dev->num_rx - 1)
333 			bd.stat |= RX_BD_WRAP;
334 
335 		ethoc_write_bd(dev, dev->num_tx + i, &bd);
336 		bd.addr += ETHOC_BUFSIZ;
337 
338 		dev->vma[dev->num_tx + i] = vma;
339 		vma += ETHOC_BUFSIZ;
340 	}
341 
342 	return 0;
343 }
344 
345 static int ethoc_reset(struct ethoc *dev)
346 {
347 	u32 mode;
348 
349 	/* TODO: reset controller? */
350 
351 	ethoc_disable_rx_and_tx(dev);
352 
353 	/* TODO: setup registers */
354 
355 	/* enable FCS generation and automatic padding */
356 	mode = ethoc_read(dev, MODER);
357 	mode |= MODER_CRC | MODER_PAD;
358 	ethoc_write(dev, MODER, mode);
359 
360 	/* set full-duplex mode */
361 	mode = ethoc_read(dev, MODER);
362 	mode |= MODER_FULLD;
363 	ethoc_write(dev, MODER, mode);
364 	ethoc_write(dev, IPGT, 0x15);
365 
366 	ethoc_ack_irq(dev, INT_MASK_ALL);
367 	ethoc_enable_irq(dev, INT_MASK_ALL);
368 	ethoc_enable_rx_and_tx(dev);
369 	return 0;
370 }
371 
372 static unsigned int ethoc_update_rx_stats(struct ethoc *dev,
373 		struct ethoc_bd *bd)
374 {
375 	struct net_device *netdev = dev->netdev;
376 	unsigned int ret = 0;
377 
378 	if (bd->stat & RX_BD_TL) {
379 		dev_err(&netdev->dev, "RX: frame too long\n");
380 		netdev->stats.rx_length_errors++;
381 		ret++;
382 	}
383 
384 	if (bd->stat & RX_BD_SF) {
385 		dev_err(&netdev->dev, "RX: frame too short\n");
386 		netdev->stats.rx_length_errors++;
387 		ret++;
388 	}
389 
390 	if (bd->stat & RX_BD_DN) {
391 		dev_err(&netdev->dev, "RX: dribble nibble\n");
392 		netdev->stats.rx_frame_errors++;
393 	}
394 
395 	if (bd->stat & RX_BD_CRC) {
396 		dev_err(&netdev->dev, "RX: wrong CRC\n");
397 		netdev->stats.rx_crc_errors++;
398 		ret++;
399 	}
400 
401 	if (bd->stat & RX_BD_OR) {
402 		dev_err(&netdev->dev, "RX: overrun\n");
403 		netdev->stats.rx_over_errors++;
404 		ret++;
405 	}
406 
407 	if (bd->stat & RX_BD_MISS)
408 		netdev->stats.rx_missed_errors++;
409 
410 	if (bd->stat & RX_BD_LC) {
411 		dev_err(&netdev->dev, "RX: late collision\n");
412 		netdev->stats.collisions++;
413 		ret++;
414 	}
415 
416 	return ret;
417 }
418 
419 static int ethoc_rx(struct net_device *dev, int limit)
420 {
421 	struct ethoc *priv = netdev_priv(dev);
422 	int count;
423 
424 	for (count = 0; count < limit; ++count) {
425 		unsigned int entry;
426 		struct ethoc_bd bd;
427 
428 		entry = priv->num_tx + priv->cur_rx;
429 		ethoc_read_bd(priv, entry, &bd);
430 		if (bd.stat & RX_BD_EMPTY) {
431 			ethoc_ack_irq(priv, INT_MASK_RX);
432 			/* If packet (interrupt) came in between checking
433 			 * BD_EMTPY and clearing the interrupt source, then we
434 			 * risk missing the packet as the RX interrupt won't
435 			 * trigger right away when we reenable it; hence, check
436 			 * BD_EMTPY here again to make sure there isn't such a
437 			 * packet waiting for us...
438 			 */
439 			ethoc_read_bd(priv, entry, &bd);
440 			if (bd.stat & RX_BD_EMPTY)
441 				break;
442 		}
443 
444 		if (ethoc_update_rx_stats(priv, &bd) == 0) {
445 			int size = bd.stat >> 16;
446 			struct sk_buff *skb;
447 
448 			size -= 4; /* strip the CRC */
449 			skb = netdev_alloc_skb_ip_align(dev, size);
450 
451 			if (likely(skb)) {
452 				void *src = priv->vma[entry];
453 				memcpy_fromio(skb_put(skb, size), src, size);
454 				skb->protocol = eth_type_trans(skb, dev);
455 				dev->stats.rx_packets++;
456 				dev->stats.rx_bytes += size;
457 				netif_receive_skb(skb);
458 			} else {
459 				if (net_ratelimit())
460 					dev_warn(&dev->dev,
461 					    "low on memory - packet dropped\n");
462 
463 				dev->stats.rx_dropped++;
464 				break;
465 			}
466 		}
467 
468 		/* clear the buffer descriptor so it can be reused */
469 		bd.stat &= ~RX_BD_STATS;
470 		bd.stat |=  RX_BD_EMPTY;
471 		ethoc_write_bd(priv, entry, &bd);
472 		if (++priv->cur_rx == priv->num_rx)
473 			priv->cur_rx = 0;
474 	}
475 
476 	return count;
477 }
478 
479 static void ethoc_update_tx_stats(struct ethoc *dev, struct ethoc_bd *bd)
480 {
481 	struct net_device *netdev = dev->netdev;
482 
483 	if (bd->stat & TX_BD_LC) {
484 		dev_err(&netdev->dev, "TX: late collision\n");
485 		netdev->stats.tx_window_errors++;
486 	}
487 
488 	if (bd->stat & TX_BD_RL) {
489 		dev_err(&netdev->dev, "TX: retransmit limit\n");
490 		netdev->stats.tx_aborted_errors++;
491 	}
492 
493 	if (bd->stat & TX_BD_UR) {
494 		dev_err(&netdev->dev, "TX: underrun\n");
495 		netdev->stats.tx_fifo_errors++;
496 	}
497 
498 	if (bd->stat & TX_BD_CS) {
499 		dev_err(&netdev->dev, "TX: carrier sense lost\n");
500 		netdev->stats.tx_carrier_errors++;
501 	}
502 
503 	if (bd->stat & TX_BD_STATS)
504 		netdev->stats.tx_errors++;
505 
506 	netdev->stats.collisions += (bd->stat >> 4) & 0xf;
507 	netdev->stats.tx_bytes += bd->stat >> 16;
508 	netdev->stats.tx_packets++;
509 }
510 
511 static int ethoc_tx(struct net_device *dev, int limit)
512 {
513 	struct ethoc *priv = netdev_priv(dev);
514 	int count;
515 	struct ethoc_bd bd;
516 
517 	for (count = 0; count < limit; ++count) {
518 		unsigned int entry;
519 
520 		entry = priv->dty_tx & (priv->num_tx-1);
521 
522 		ethoc_read_bd(priv, entry, &bd);
523 
524 		if (bd.stat & TX_BD_READY || (priv->dty_tx == priv->cur_tx)) {
525 			ethoc_ack_irq(priv, INT_MASK_TX);
526 			/* If interrupt came in between reading in the BD
527 			 * and clearing the interrupt source, then we risk
528 			 * missing the event as the TX interrupt won't trigger
529 			 * right away when we reenable it; hence, check
530 			 * BD_EMPTY here again to make sure there isn't such an
531 			 * event pending...
532 			 */
533 			ethoc_read_bd(priv, entry, &bd);
534 			if (bd.stat & TX_BD_READY ||
535 			    (priv->dty_tx == priv->cur_tx))
536 				break;
537 		}
538 
539 		ethoc_update_tx_stats(priv, &bd);
540 		priv->dty_tx++;
541 	}
542 
543 	if ((priv->cur_tx - priv->dty_tx) <= (priv->num_tx / 2))
544 		netif_wake_queue(dev);
545 
546 	return count;
547 }
548 
549 static irqreturn_t ethoc_interrupt(int irq, void *dev_id)
550 {
551 	struct net_device *dev = dev_id;
552 	struct ethoc *priv = netdev_priv(dev);
553 	u32 pending;
554 	u32 mask;
555 
556 	/* Figure out what triggered the interrupt...
557 	 * The tricky bit here is that the interrupt source bits get
558 	 * set in INT_SOURCE for an event regardless of whether that
559 	 * event is masked or not.  Thus, in order to figure out what
560 	 * triggered the interrupt, we need to remove the sources
561 	 * for all events that are currently masked.  This behaviour
562 	 * is not particularly well documented but reasonable...
563 	 */
564 	mask = ethoc_read(priv, INT_MASK);
565 	pending = ethoc_read(priv, INT_SOURCE);
566 	pending &= mask;
567 
568 	if (unlikely(pending == 0))
569 		return IRQ_NONE;
570 
571 	ethoc_ack_irq(priv, pending);
572 
573 	/* We always handle the dropped packet interrupt */
574 	if (pending & INT_MASK_BUSY) {
575 		dev_err(&dev->dev, "packet dropped\n");
576 		dev->stats.rx_dropped++;
577 	}
578 
579 	/* Handle receive/transmit event by switching to polling */
580 	if (pending & (INT_MASK_TX | INT_MASK_RX)) {
581 		ethoc_disable_irq(priv, INT_MASK_TX | INT_MASK_RX);
582 		napi_schedule(&priv->napi);
583 	}
584 
585 	return IRQ_HANDLED;
586 }
587 
588 static int ethoc_get_mac_address(struct net_device *dev, void *addr)
589 {
590 	struct ethoc *priv = netdev_priv(dev);
591 	u8 *mac = (u8 *)addr;
592 	u32 reg;
593 
594 	reg = ethoc_read(priv, MAC_ADDR0);
595 	mac[2] = (reg >> 24) & 0xff;
596 	mac[3] = (reg >> 16) & 0xff;
597 	mac[4] = (reg >>  8) & 0xff;
598 	mac[5] = (reg >>  0) & 0xff;
599 
600 	reg = ethoc_read(priv, MAC_ADDR1);
601 	mac[0] = (reg >>  8) & 0xff;
602 	mac[1] = (reg >>  0) & 0xff;
603 
604 	return 0;
605 }
606 
607 static int ethoc_poll(struct napi_struct *napi, int budget)
608 {
609 	struct ethoc *priv = container_of(napi, struct ethoc, napi);
610 	int rx_work_done = 0;
611 	int tx_work_done = 0;
612 
613 	rx_work_done = ethoc_rx(priv->netdev, budget);
614 	tx_work_done = ethoc_tx(priv->netdev, budget);
615 
616 	if (rx_work_done < budget && tx_work_done < budget) {
617 		napi_complete(napi);
618 		ethoc_enable_irq(priv, INT_MASK_TX | INT_MASK_RX);
619 	}
620 
621 	return rx_work_done;
622 }
623 
624 static int ethoc_mdio_read(struct mii_bus *bus, int phy, int reg)
625 {
626 	struct ethoc *priv = bus->priv;
627 	int i;
628 
629 	ethoc_write(priv, MIIADDRESS, MIIADDRESS_ADDR(phy, reg));
630 	ethoc_write(priv, MIICOMMAND, MIICOMMAND_READ);
631 
632 	for (i = 0; i < 5; i++) {
633 		u32 status = ethoc_read(priv, MIISTATUS);
634 		if (!(status & MIISTATUS_BUSY)) {
635 			u32 data = ethoc_read(priv, MIIRX_DATA);
636 			/* reset MII command register */
637 			ethoc_write(priv, MIICOMMAND, 0);
638 			return data;
639 		}
640 		usleep_range(100, 200);
641 	}
642 
643 	return -EBUSY;
644 }
645 
646 static int ethoc_mdio_write(struct mii_bus *bus, int phy, int reg, u16 val)
647 {
648 	struct ethoc *priv = bus->priv;
649 	int i;
650 
651 	ethoc_write(priv, MIIADDRESS, MIIADDRESS_ADDR(phy, reg));
652 	ethoc_write(priv, MIITX_DATA, val);
653 	ethoc_write(priv, MIICOMMAND, MIICOMMAND_WRITE);
654 
655 	for (i = 0; i < 5; i++) {
656 		u32 stat = ethoc_read(priv, MIISTATUS);
657 		if (!(stat & MIISTATUS_BUSY)) {
658 			/* reset MII command register */
659 			ethoc_write(priv, MIICOMMAND, 0);
660 			return 0;
661 		}
662 		usleep_range(100, 200);
663 	}
664 
665 	return -EBUSY;
666 }
667 
668 static void ethoc_mdio_poll(struct net_device *dev)
669 {
670 }
671 
672 static int ethoc_mdio_probe(struct net_device *dev)
673 {
674 	struct ethoc *priv = netdev_priv(dev);
675 	struct phy_device *phy;
676 	int err;
677 
678 	if (priv->phy_id != -1)
679 		phy = mdiobus_get_phy(priv->mdio, priv->phy_id);
680 	else
681 		phy = phy_find_first(priv->mdio);
682 
683 	if (!phy) {
684 		dev_err(&dev->dev, "no PHY found\n");
685 		return -ENXIO;
686 	}
687 
688 	err = phy_connect_direct(dev, phy, ethoc_mdio_poll,
689 				 PHY_INTERFACE_MODE_GMII);
690 	if (err) {
691 		dev_err(&dev->dev, "could not attach to PHY\n");
692 		return err;
693 	}
694 
695 	phy->advertising &= ~(ADVERTISED_1000baseT_Full |
696 			      ADVERTISED_1000baseT_Half);
697 	phy->supported &= ~(SUPPORTED_1000baseT_Full |
698 			    SUPPORTED_1000baseT_Half);
699 
700 	return 0;
701 }
702 
703 static int ethoc_open(struct net_device *dev)
704 {
705 	struct ethoc *priv = netdev_priv(dev);
706 	int ret;
707 
708 	ret = request_irq(dev->irq, ethoc_interrupt, IRQF_SHARED,
709 			dev->name, dev);
710 	if (ret)
711 		return ret;
712 
713 	ethoc_init_ring(priv, dev->mem_start);
714 	ethoc_reset(priv);
715 
716 	if (netif_queue_stopped(dev)) {
717 		dev_dbg(&dev->dev, " resuming queue\n");
718 		netif_wake_queue(dev);
719 	} else {
720 		dev_dbg(&dev->dev, " starting queue\n");
721 		netif_start_queue(dev);
722 	}
723 
724 	phy_start(dev->phydev);
725 	napi_enable(&priv->napi);
726 
727 	if (netif_msg_ifup(priv)) {
728 		dev_info(&dev->dev, "I/O: %08lx Memory: %08lx-%08lx\n",
729 				dev->base_addr, dev->mem_start, dev->mem_end);
730 	}
731 
732 	return 0;
733 }
734 
735 static int ethoc_stop(struct net_device *dev)
736 {
737 	struct ethoc *priv = netdev_priv(dev);
738 
739 	napi_disable(&priv->napi);
740 
741 	if (dev->phydev)
742 		phy_stop(dev->phydev);
743 
744 	ethoc_disable_rx_and_tx(priv);
745 	free_irq(dev->irq, dev);
746 
747 	if (!netif_queue_stopped(dev))
748 		netif_stop_queue(dev);
749 
750 	return 0;
751 }
752 
753 static int ethoc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
754 {
755 	struct ethoc *priv = netdev_priv(dev);
756 	struct mii_ioctl_data *mdio = if_mii(ifr);
757 	struct phy_device *phy = NULL;
758 
759 	if (!netif_running(dev))
760 		return -EINVAL;
761 
762 	if (cmd != SIOCGMIIPHY) {
763 		if (mdio->phy_id >= PHY_MAX_ADDR)
764 			return -ERANGE;
765 
766 		phy = mdiobus_get_phy(priv->mdio, mdio->phy_id);
767 		if (!phy)
768 			return -ENODEV;
769 	} else {
770 		phy = dev->phydev;
771 	}
772 
773 	return phy_mii_ioctl(phy, ifr, cmd);
774 }
775 
776 static void ethoc_do_set_mac_address(struct net_device *dev)
777 {
778 	struct ethoc *priv = netdev_priv(dev);
779 	unsigned char *mac = dev->dev_addr;
780 
781 	ethoc_write(priv, MAC_ADDR0, (mac[2] << 24) | (mac[3] << 16) |
782 				     (mac[4] <<  8) | (mac[5] <<  0));
783 	ethoc_write(priv, MAC_ADDR1, (mac[0] <<  8) | (mac[1] <<  0));
784 }
785 
786 static int ethoc_set_mac_address(struct net_device *dev, void *p)
787 {
788 	const struct sockaddr *addr = p;
789 
790 	if (!is_valid_ether_addr(addr->sa_data))
791 		return -EADDRNOTAVAIL;
792 	memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
793 	ethoc_do_set_mac_address(dev);
794 	return 0;
795 }
796 
797 static void ethoc_set_multicast_list(struct net_device *dev)
798 {
799 	struct ethoc *priv = netdev_priv(dev);
800 	u32 mode = ethoc_read(priv, MODER);
801 	struct netdev_hw_addr *ha;
802 	u32 hash[2] = { 0, 0 };
803 
804 	/* set loopback mode if requested */
805 	if (dev->flags & IFF_LOOPBACK)
806 		mode |=  MODER_LOOP;
807 	else
808 		mode &= ~MODER_LOOP;
809 
810 	/* receive broadcast frames if requested */
811 	if (dev->flags & IFF_BROADCAST)
812 		mode &= ~MODER_BRO;
813 	else
814 		mode |=  MODER_BRO;
815 
816 	/* enable promiscuous mode if requested */
817 	if (dev->flags & IFF_PROMISC)
818 		mode |=  MODER_PRO;
819 	else
820 		mode &= ~MODER_PRO;
821 
822 	ethoc_write(priv, MODER, mode);
823 
824 	/* receive multicast frames */
825 	if (dev->flags & IFF_ALLMULTI) {
826 		hash[0] = 0xffffffff;
827 		hash[1] = 0xffffffff;
828 	} else {
829 		netdev_for_each_mc_addr(ha, dev) {
830 			u32 crc = ether_crc(ETH_ALEN, ha->addr);
831 			int bit = (crc >> 26) & 0x3f;
832 			hash[bit >> 5] |= 1 << (bit & 0x1f);
833 		}
834 	}
835 
836 	ethoc_write(priv, ETH_HASH0, hash[0]);
837 	ethoc_write(priv, ETH_HASH1, hash[1]);
838 }
839 
840 static int ethoc_change_mtu(struct net_device *dev, int new_mtu)
841 {
842 	return -ENOSYS;
843 }
844 
845 static void ethoc_tx_timeout(struct net_device *dev)
846 {
847 	struct ethoc *priv = netdev_priv(dev);
848 	u32 pending = ethoc_read(priv, INT_SOURCE);
849 	if (likely(pending))
850 		ethoc_interrupt(dev->irq, dev);
851 }
852 
853 static netdev_tx_t ethoc_start_xmit(struct sk_buff *skb, struct net_device *dev)
854 {
855 	struct ethoc *priv = netdev_priv(dev);
856 	struct ethoc_bd bd;
857 	unsigned int entry;
858 	void *dest;
859 
860 	if (skb_put_padto(skb, ETHOC_ZLEN)) {
861 		dev->stats.tx_errors++;
862 		goto out_no_free;
863 	}
864 
865 	if (unlikely(skb->len > ETHOC_BUFSIZ)) {
866 		dev->stats.tx_errors++;
867 		goto out;
868 	}
869 
870 	entry = priv->cur_tx % priv->num_tx;
871 	spin_lock_irq(&priv->lock);
872 	priv->cur_tx++;
873 
874 	ethoc_read_bd(priv, entry, &bd);
875 	if (unlikely(skb->len < ETHOC_ZLEN))
876 		bd.stat |=  TX_BD_PAD;
877 	else
878 		bd.stat &= ~TX_BD_PAD;
879 
880 	dest = priv->vma[entry];
881 	memcpy_toio(dest, skb->data, skb->len);
882 
883 	bd.stat &= ~(TX_BD_STATS | TX_BD_LEN_MASK);
884 	bd.stat |= TX_BD_LEN(skb->len);
885 	ethoc_write_bd(priv, entry, &bd);
886 
887 	bd.stat |= TX_BD_READY;
888 	ethoc_write_bd(priv, entry, &bd);
889 
890 	if (priv->cur_tx == (priv->dty_tx + priv->num_tx)) {
891 		dev_dbg(&dev->dev, "stopping queue\n");
892 		netif_stop_queue(dev);
893 	}
894 
895 	spin_unlock_irq(&priv->lock);
896 	skb_tx_timestamp(skb);
897 out:
898 	dev_kfree_skb(skb);
899 out_no_free:
900 	return NETDEV_TX_OK;
901 }
902 
903 static int ethoc_get_regs_len(struct net_device *netdev)
904 {
905 	return ETH_END;
906 }
907 
908 static void ethoc_get_regs(struct net_device *dev, struct ethtool_regs *regs,
909 			   void *p)
910 {
911 	struct ethoc *priv = netdev_priv(dev);
912 	u32 *regs_buff = p;
913 	unsigned i;
914 
915 	regs->version = 0;
916 	for (i = 0; i < ETH_END / sizeof(u32); ++i)
917 		regs_buff[i] = ethoc_read(priv, i * sizeof(u32));
918 }
919 
920 static void ethoc_get_ringparam(struct net_device *dev,
921 				struct ethtool_ringparam *ring)
922 {
923 	struct ethoc *priv = netdev_priv(dev);
924 
925 	ring->rx_max_pending = priv->num_bd - 1;
926 	ring->rx_mini_max_pending = 0;
927 	ring->rx_jumbo_max_pending = 0;
928 	ring->tx_max_pending = priv->num_bd - 1;
929 
930 	ring->rx_pending = priv->num_rx;
931 	ring->rx_mini_pending = 0;
932 	ring->rx_jumbo_pending = 0;
933 	ring->tx_pending = priv->num_tx;
934 }
935 
936 static int ethoc_set_ringparam(struct net_device *dev,
937 			       struct ethtool_ringparam *ring)
938 {
939 	struct ethoc *priv = netdev_priv(dev);
940 
941 	if (ring->tx_pending < 1 || ring->rx_pending < 1 ||
942 	    ring->tx_pending + ring->rx_pending > priv->num_bd)
943 		return -EINVAL;
944 	if (ring->rx_mini_pending || ring->rx_jumbo_pending)
945 		return -EINVAL;
946 
947 	if (netif_running(dev)) {
948 		netif_tx_disable(dev);
949 		ethoc_disable_rx_and_tx(priv);
950 		ethoc_disable_irq(priv, INT_MASK_TX | INT_MASK_RX);
951 		synchronize_irq(dev->irq);
952 	}
953 
954 	priv->num_tx = rounddown_pow_of_two(ring->tx_pending);
955 	priv->num_rx = ring->rx_pending;
956 	ethoc_init_ring(priv, dev->mem_start);
957 
958 	if (netif_running(dev)) {
959 		ethoc_enable_irq(priv, INT_MASK_TX | INT_MASK_RX);
960 		ethoc_enable_rx_and_tx(priv);
961 		netif_wake_queue(dev);
962 	}
963 	return 0;
964 }
965 
966 const struct ethtool_ops ethoc_ethtool_ops = {
967 	.get_regs_len = ethoc_get_regs_len,
968 	.get_regs = ethoc_get_regs,
969 	.get_link = ethtool_op_get_link,
970 	.get_ringparam = ethoc_get_ringparam,
971 	.set_ringparam = ethoc_set_ringparam,
972 	.get_ts_info = ethtool_op_get_ts_info,
973 	.get_link_ksettings = phy_ethtool_get_link_ksettings,
974 	.set_link_ksettings = phy_ethtool_set_link_ksettings,
975 };
976 
977 static const struct net_device_ops ethoc_netdev_ops = {
978 	.ndo_open = ethoc_open,
979 	.ndo_stop = ethoc_stop,
980 	.ndo_do_ioctl = ethoc_ioctl,
981 	.ndo_set_mac_address = ethoc_set_mac_address,
982 	.ndo_set_rx_mode = ethoc_set_multicast_list,
983 	.ndo_change_mtu = ethoc_change_mtu,
984 	.ndo_tx_timeout = ethoc_tx_timeout,
985 	.ndo_start_xmit = ethoc_start_xmit,
986 };
987 
988 /**
989  * ethoc_probe - initialize OpenCores ethernet MAC
990  * pdev:	platform device
991  */
992 static int ethoc_probe(struct platform_device *pdev)
993 {
994 	struct net_device *netdev = NULL;
995 	struct resource *res = NULL;
996 	struct resource *mmio = NULL;
997 	struct resource *mem = NULL;
998 	struct ethoc *priv = NULL;
999 	int num_bd;
1000 	int ret = 0;
1001 	bool random_mac = false;
1002 	struct ethoc_platform_data *pdata = dev_get_platdata(&pdev->dev);
1003 	u32 eth_clkfreq = pdata ? pdata->eth_clkfreq : 0;
1004 
1005 	/* allocate networking device */
1006 	netdev = alloc_etherdev(sizeof(struct ethoc));
1007 	if (!netdev) {
1008 		ret = -ENOMEM;
1009 		goto out;
1010 	}
1011 
1012 	SET_NETDEV_DEV(netdev, &pdev->dev);
1013 	platform_set_drvdata(pdev, netdev);
1014 
1015 	/* obtain I/O memory space */
1016 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1017 	if (!res) {
1018 		dev_err(&pdev->dev, "cannot obtain I/O memory space\n");
1019 		ret = -ENXIO;
1020 		goto free;
1021 	}
1022 
1023 	mmio = devm_request_mem_region(&pdev->dev, res->start,
1024 			resource_size(res), res->name);
1025 	if (!mmio) {
1026 		dev_err(&pdev->dev, "cannot request I/O memory space\n");
1027 		ret = -ENXIO;
1028 		goto free;
1029 	}
1030 
1031 	netdev->base_addr = mmio->start;
1032 
1033 	/* obtain buffer memory space */
1034 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1035 	if (res) {
1036 		mem = devm_request_mem_region(&pdev->dev, res->start,
1037 			resource_size(res), res->name);
1038 		if (!mem) {
1039 			dev_err(&pdev->dev, "cannot request memory space\n");
1040 			ret = -ENXIO;
1041 			goto free;
1042 		}
1043 
1044 		netdev->mem_start = mem->start;
1045 		netdev->mem_end   = mem->end;
1046 	}
1047 
1048 
1049 	/* obtain device IRQ number */
1050 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1051 	if (!res) {
1052 		dev_err(&pdev->dev, "cannot obtain IRQ\n");
1053 		ret = -ENXIO;
1054 		goto free;
1055 	}
1056 
1057 	netdev->irq = res->start;
1058 
1059 	/* setup driver-private data */
1060 	priv = netdev_priv(netdev);
1061 	priv->netdev = netdev;
1062 	priv->dma_alloc = 0;
1063 	priv->io_region_size = resource_size(mmio);
1064 
1065 	priv->iobase = devm_ioremap_nocache(&pdev->dev, netdev->base_addr,
1066 			resource_size(mmio));
1067 	if (!priv->iobase) {
1068 		dev_err(&pdev->dev, "cannot remap I/O memory space\n");
1069 		ret = -ENXIO;
1070 		goto free;
1071 	}
1072 
1073 	if (netdev->mem_end) {
1074 		priv->membase = devm_ioremap_nocache(&pdev->dev,
1075 			netdev->mem_start, resource_size(mem));
1076 		if (!priv->membase) {
1077 			dev_err(&pdev->dev, "cannot remap memory space\n");
1078 			ret = -ENXIO;
1079 			goto free;
1080 		}
1081 	} else {
1082 		/* Allocate buffer memory */
1083 		priv->membase = dmam_alloc_coherent(&pdev->dev,
1084 			buffer_size, (void *)&netdev->mem_start,
1085 			GFP_KERNEL);
1086 		if (!priv->membase) {
1087 			dev_err(&pdev->dev, "cannot allocate %dB buffer\n",
1088 				buffer_size);
1089 			ret = -ENOMEM;
1090 			goto free;
1091 		}
1092 		netdev->mem_end = netdev->mem_start + buffer_size;
1093 		priv->dma_alloc = buffer_size;
1094 	}
1095 
1096 	priv->big_endian = pdata ? pdata->big_endian :
1097 		of_device_is_big_endian(pdev->dev.of_node);
1098 
1099 	/* calculate the number of TX/RX buffers, maximum 128 supported */
1100 	num_bd = min_t(unsigned int,
1101 		128, (netdev->mem_end - netdev->mem_start + 1) / ETHOC_BUFSIZ);
1102 	if (num_bd < 4) {
1103 		ret = -ENODEV;
1104 		goto free;
1105 	}
1106 	priv->num_bd = num_bd;
1107 	/* num_tx must be a power of two */
1108 	priv->num_tx = rounddown_pow_of_two(num_bd >> 1);
1109 	priv->num_rx = num_bd - priv->num_tx;
1110 
1111 	dev_dbg(&pdev->dev, "ethoc: num_tx: %d num_rx: %d\n",
1112 		priv->num_tx, priv->num_rx);
1113 
1114 	priv->vma = devm_kzalloc(&pdev->dev, num_bd*sizeof(void *), GFP_KERNEL);
1115 	if (!priv->vma) {
1116 		ret = -ENOMEM;
1117 		goto free;
1118 	}
1119 
1120 	/* Allow the platform setup code to pass in a MAC address. */
1121 	if (pdata) {
1122 		memcpy(netdev->dev_addr, pdata->hwaddr, IFHWADDRLEN);
1123 		priv->phy_id = pdata->phy_id;
1124 	} else {
1125 		const uint8_t *mac;
1126 
1127 		mac = of_get_property(pdev->dev.of_node,
1128 				      "local-mac-address",
1129 				      NULL);
1130 		if (mac)
1131 			memcpy(netdev->dev_addr, mac, IFHWADDRLEN);
1132 		priv->phy_id = -1;
1133 	}
1134 
1135 	/* Check that the given MAC address is valid. If it isn't, read the
1136 	 * current MAC from the controller.
1137 	 */
1138 	if (!is_valid_ether_addr(netdev->dev_addr))
1139 		ethoc_get_mac_address(netdev, netdev->dev_addr);
1140 
1141 	/* Check the MAC again for validity, if it still isn't choose and
1142 	 * program a random one.
1143 	 */
1144 	if (!is_valid_ether_addr(netdev->dev_addr)) {
1145 		eth_random_addr(netdev->dev_addr);
1146 		random_mac = true;
1147 	}
1148 
1149 	ethoc_do_set_mac_address(netdev);
1150 
1151 	if (random_mac)
1152 		netdev->addr_assign_type = NET_ADDR_RANDOM;
1153 
1154 	/* Allow the platform setup code to adjust MII management bus clock. */
1155 	if (!eth_clkfreq) {
1156 		struct clk *clk = devm_clk_get(&pdev->dev, NULL);
1157 
1158 		if (!IS_ERR(clk)) {
1159 			priv->clk = clk;
1160 			clk_prepare_enable(clk);
1161 			eth_clkfreq = clk_get_rate(clk);
1162 		}
1163 	}
1164 	if (eth_clkfreq) {
1165 		u32 clkdiv = MIIMODER_CLKDIV(eth_clkfreq / 2500000 + 1);
1166 
1167 		if (!clkdiv)
1168 			clkdiv = 2;
1169 		dev_dbg(&pdev->dev, "setting MII clkdiv to %u\n", clkdiv);
1170 		ethoc_write(priv, MIIMODER,
1171 			    (ethoc_read(priv, MIIMODER) & MIIMODER_NOPRE) |
1172 			    clkdiv);
1173 	}
1174 
1175 	/* register MII bus */
1176 	priv->mdio = mdiobus_alloc();
1177 	if (!priv->mdio) {
1178 		ret = -ENOMEM;
1179 		goto free2;
1180 	}
1181 
1182 	priv->mdio->name = "ethoc-mdio";
1183 	snprintf(priv->mdio->id, MII_BUS_ID_SIZE, "%s-%d",
1184 			priv->mdio->name, pdev->id);
1185 	priv->mdio->read = ethoc_mdio_read;
1186 	priv->mdio->write = ethoc_mdio_write;
1187 	priv->mdio->priv = priv;
1188 
1189 	ret = mdiobus_register(priv->mdio);
1190 	if (ret) {
1191 		dev_err(&netdev->dev, "failed to register MDIO bus\n");
1192 		goto free2;
1193 	}
1194 
1195 	ret = ethoc_mdio_probe(netdev);
1196 	if (ret) {
1197 		dev_err(&netdev->dev, "failed to probe MDIO bus\n");
1198 		goto error;
1199 	}
1200 
1201 	/* setup the net_device structure */
1202 	netdev->netdev_ops = &ethoc_netdev_ops;
1203 	netdev->watchdog_timeo = ETHOC_TIMEOUT;
1204 	netdev->features |= 0;
1205 	netdev->ethtool_ops = &ethoc_ethtool_ops;
1206 
1207 	/* setup NAPI */
1208 	netif_napi_add(netdev, &priv->napi, ethoc_poll, 64);
1209 
1210 	spin_lock_init(&priv->lock);
1211 
1212 	ret = register_netdev(netdev);
1213 	if (ret < 0) {
1214 		dev_err(&netdev->dev, "failed to register interface\n");
1215 		goto error2;
1216 	}
1217 
1218 	goto out;
1219 
1220 error2:
1221 	netif_napi_del(&priv->napi);
1222 error:
1223 	mdiobus_unregister(priv->mdio);
1224 	mdiobus_free(priv->mdio);
1225 free2:
1226 	if (priv->clk)
1227 		clk_disable_unprepare(priv->clk);
1228 free:
1229 	free_netdev(netdev);
1230 out:
1231 	return ret;
1232 }
1233 
1234 /**
1235  * ethoc_remove - shutdown OpenCores ethernet MAC
1236  * @pdev:	platform device
1237  */
1238 static int ethoc_remove(struct platform_device *pdev)
1239 {
1240 	struct net_device *netdev = platform_get_drvdata(pdev);
1241 	struct ethoc *priv = netdev_priv(netdev);
1242 
1243 	if (netdev) {
1244 		netif_napi_del(&priv->napi);
1245 		phy_disconnect(netdev->phydev);
1246 
1247 		if (priv->mdio) {
1248 			mdiobus_unregister(priv->mdio);
1249 			mdiobus_free(priv->mdio);
1250 		}
1251 		if (priv->clk)
1252 			clk_disable_unprepare(priv->clk);
1253 		unregister_netdev(netdev);
1254 		free_netdev(netdev);
1255 	}
1256 
1257 	return 0;
1258 }
1259 
1260 #ifdef CONFIG_PM
1261 static int ethoc_suspend(struct platform_device *pdev, pm_message_t state)
1262 {
1263 	return -ENOSYS;
1264 }
1265 
1266 static int ethoc_resume(struct platform_device *pdev)
1267 {
1268 	return -ENOSYS;
1269 }
1270 #else
1271 # define ethoc_suspend NULL
1272 # define ethoc_resume  NULL
1273 #endif
1274 
1275 static const struct of_device_id ethoc_match[] = {
1276 	{ .compatible = "opencores,ethoc", },
1277 	{},
1278 };
1279 MODULE_DEVICE_TABLE(of, ethoc_match);
1280 
1281 static struct platform_driver ethoc_driver = {
1282 	.probe   = ethoc_probe,
1283 	.remove  = ethoc_remove,
1284 	.suspend = ethoc_suspend,
1285 	.resume  = ethoc_resume,
1286 	.driver  = {
1287 		.name = "ethoc",
1288 		.of_match_table = ethoc_match,
1289 	},
1290 };
1291 
1292 module_platform_driver(ethoc_driver);
1293 
1294 MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
1295 MODULE_DESCRIPTION("OpenCores Ethernet MAC driver");
1296 MODULE_LICENSE("GPL v2");
1297 
1298