xref: /openbmc/linux/drivers/net/ethernet/ethoc.c (revision 9cfc5c90)
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  * @phy:	attached PHY
196  * @mdio:	MDIO bus for PHY access
197  * @phy_id:	address of attached PHY
198  */
199 struct ethoc {
200 	void __iomem *iobase;
201 	void __iomem *membase;
202 	int dma_alloc;
203 	resource_size_t io_region_size;
204 	bool big_endian;
205 
206 	unsigned int num_bd;
207 	unsigned int num_tx;
208 	unsigned int cur_tx;
209 	unsigned int dty_tx;
210 
211 	unsigned int num_rx;
212 	unsigned int cur_rx;
213 
214 	void **vma;
215 
216 	struct net_device *netdev;
217 	struct napi_struct napi;
218 	u32 msg_enable;
219 
220 	spinlock_t lock;
221 
222 	struct phy_device *phy;
223 	struct mii_bus *mdio;
224 	struct clk *clk;
225 	s8 phy_id;
226 };
227 
228 /**
229  * struct ethoc_bd - buffer descriptor
230  * @stat:	buffer statistics
231  * @addr:	physical memory address
232  */
233 struct ethoc_bd {
234 	u32 stat;
235 	u32 addr;
236 };
237 
238 static inline u32 ethoc_read(struct ethoc *dev, loff_t offset)
239 {
240 	if (dev->big_endian)
241 		return ioread32be(dev->iobase + offset);
242 	else
243 		return ioread32(dev->iobase + offset);
244 }
245 
246 static inline void ethoc_write(struct ethoc *dev, loff_t offset, u32 data)
247 {
248 	if (dev->big_endian)
249 		iowrite32be(data, dev->iobase + offset);
250 	else
251 		iowrite32(data, dev->iobase + offset);
252 }
253 
254 static inline void ethoc_read_bd(struct ethoc *dev, int index,
255 		struct ethoc_bd *bd)
256 {
257 	loff_t offset = ETHOC_BD_BASE + (index * sizeof(struct ethoc_bd));
258 	bd->stat = ethoc_read(dev, offset + 0);
259 	bd->addr = ethoc_read(dev, offset + 4);
260 }
261 
262 static inline void ethoc_write_bd(struct ethoc *dev, int index,
263 		const struct ethoc_bd *bd)
264 {
265 	loff_t offset = ETHOC_BD_BASE + (index * sizeof(struct ethoc_bd));
266 	ethoc_write(dev, offset + 0, bd->stat);
267 	ethoc_write(dev, offset + 4, bd->addr);
268 }
269 
270 static inline void ethoc_enable_irq(struct ethoc *dev, u32 mask)
271 {
272 	u32 imask = ethoc_read(dev, INT_MASK);
273 	imask |= mask;
274 	ethoc_write(dev, INT_MASK, imask);
275 }
276 
277 static inline void ethoc_disable_irq(struct ethoc *dev, u32 mask)
278 {
279 	u32 imask = ethoc_read(dev, INT_MASK);
280 	imask &= ~mask;
281 	ethoc_write(dev, INT_MASK, imask);
282 }
283 
284 static inline void ethoc_ack_irq(struct ethoc *dev, u32 mask)
285 {
286 	ethoc_write(dev, INT_SOURCE, mask);
287 }
288 
289 static inline void ethoc_enable_rx_and_tx(struct ethoc *dev)
290 {
291 	u32 mode = ethoc_read(dev, MODER);
292 	mode |= MODER_RXEN | MODER_TXEN;
293 	ethoc_write(dev, MODER, mode);
294 }
295 
296 static inline void ethoc_disable_rx_and_tx(struct ethoc *dev)
297 {
298 	u32 mode = ethoc_read(dev, MODER);
299 	mode &= ~(MODER_RXEN | MODER_TXEN);
300 	ethoc_write(dev, MODER, mode);
301 }
302 
303 static int ethoc_init_ring(struct ethoc *dev, unsigned long mem_start)
304 {
305 	struct ethoc_bd bd;
306 	int i;
307 	void *vma;
308 
309 	dev->cur_tx = 0;
310 	dev->dty_tx = 0;
311 	dev->cur_rx = 0;
312 
313 	ethoc_write(dev, TX_BD_NUM, dev->num_tx);
314 
315 	/* setup transmission buffers */
316 	bd.addr = mem_start;
317 	bd.stat = TX_BD_IRQ | TX_BD_CRC;
318 	vma = dev->membase;
319 
320 	for (i = 0; i < dev->num_tx; i++) {
321 		if (i == dev->num_tx - 1)
322 			bd.stat |= TX_BD_WRAP;
323 
324 		ethoc_write_bd(dev, i, &bd);
325 		bd.addr += ETHOC_BUFSIZ;
326 
327 		dev->vma[i] = vma;
328 		vma += ETHOC_BUFSIZ;
329 	}
330 
331 	bd.stat = RX_BD_EMPTY | RX_BD_IRQ;
332 
333 	for (i = 0; i < dev->num_rx; i++) {
334 		if (i == dev->num_rx - 1)
335 			bd.stat |= RX_BD_WRAP;
336 
337 		ethoc_write_bd(dev, dev->num_tx + i, &bd);
338 		bd.addr += ETHOC_BUFSIZ;
339 
340 		dev->vma[dev->num_tx + i] = vma;
341 		vma += ETHOC_BUFSIZ;
342 	}
343 
344 	return 0;
345 }
346 
347 static int ethoc_reset(struct ethoc *dev)
348 {
349 	u32 mode;
350 
351 	/* TODO: reset controller? */
352 
353 	ethoc_disable_rx_and_tx(dev);
354 
355 	/* TODO: setup registers */
356 
357 	/* enable FCS generation and automatic padding */
358 	mode = ethoc_read(dev, MODER);
359 	mode |= MODER_CRC | MODER_PAD;
360 	ethoc_write(dev, MODER, mode);
361 
362 	/* set full-duplex mode */
363 	mode = ethoc_read(dev, MODER);
364 	mode |= MODER_FULLD;
365 	ethoc_write(dev, MODER, mode);
366 	ethoc_write(dev, IPGT, 0x15);
367 
368 	ethoc_ack_irq(dev, INT_MASK_ALL);
369 	ethoc_enable_irq(dev, INT_MASK_ALL);
370 	ethoc_enable_rx_and_tx(dev);
371 	return 0;
372 }
373 
374 static unsigned int ethoc_update_rx_stats(struct ethoc *dev,
375 		struct ethoc_bd *bd)
376 {
377 	struct net_device *netdev = dev->netdev;
378 	unsigned int ret = 0;
379 
380 	if (bd->stat & RX_BD_TL) {
381 		dev_err(&netdev->dev, "RX: frame too long\n");
382 		netdev->stats.rx_length_errors++;
383 		ret++;
384 	}
385 
386 	if (bd->stat & RX_BD_SF) {
387 		dev_err(&netdev->dev, "RX: frame too short\n");
388 		netdev->stats.rx_length_errors++;
389 		ret++;
390 	}
391 
392 	if (bd->stat & RX_BD_DN) {
393 		dev_err(&netdev->dev, "RX: dribble nibble\n");
394 		netdev->stats.rx_frame_errors++;
395 	}
396 
397 	if (bd->stat & RX_BD_CRC) {
398 		dev_err(&netdev->dev, "RX: wrong CRC\n");
399 		netdev->stats.rx_crc_errors++;
400 		ret++;
401 	}
402 
403 	if (bd->stat & RX_BD_OR) {
404 		dev_err(&netdev->dev, "RX: overrun\n");
405 		netdev->stats.rx_over_errors++;
406 		ret++;
407 	}
408 
409 	if (bd->stat & RX_BD_MISS)
410 		netdev->stats.rx_missed_errors++;
411 
412 	if (bd->stat & RX_BD_LC) {
413 		dev_err(&netdev->dev, "RX: late collision\n");
414 		netdev->stats.collisions++;
415 		ret++;
416 	}
417 
418 	return ret;
419 }
420 
421 static int ethoc_rx(struct net_device *dev, int limit)
422 {
423 	struct ethoc *priv = netdev_priv(dev);
424 	int count;
425 
426 	for (count = 0; count < limit; ++count) {
427 		unsigned int entry;
428 		struct ethoc_bd bd;
429 
430 		entry = priv->num_tx + priv->cur_rx;
431 		ethoc_read_bd(priv, entry, &bd);
432 		if (bd.stat & RX_BD_EMPTY) {
433 			ethoc_ack_irq(priv, INT_MASK_RX);
434 			/* If packet (interrupt) came in between checking
435 			 * BD_EMTPY and clearing the interrupt source, then we
436 			 * risk missing the packet as the RX interrupt won't
437 			 * trigger right away when we reenable it; hence, check
438 			 * BD_EMTPY here again to make sure there isn't such a
439 			 * packet waiting for us...
440 			 */
441 			ethoc_read_bd(priv, entry, &bd);
442 			if (bd.stat & RX_BD_EMPTY)
443 				break;
444 		}
445 
446 		if (ethoc_update_rx_stats(priv, &bd) == 0) {
447 			int size = bd.stat >> 16;
448 			struct sk_buff *skb;
449 
450 			size -= 4; /* strip the CRC */
451 			skb = netdev_alloc_skb_ip_align(dev, size);
452 
453 			if (likely(skb)) {
454 				void *src = priv->vma[entry];
455 				memcpy_fromio(skb_put(skb, size), src, size);
456 				skb->protocol = eth_type_trans(skb, dev);
457 				dev->stats.rx_packets++;
458 				dev->stats.rx_bytes += size;
459 				netif_receive_skb(skb);
460 			} else {
461 				if (net_ratelimit())
462 					dev_warn(&dev->dev,
463 					    "low on memory - packet dropped\n");
464 
465 				dev->stats.rx_dropped++;
466 				break;
467 			}
468 		}
469 
470 		/* clear the buffer descriptor so it can be reused */
471 		bd.stat &= ~RX_BD_STATS;
472 		bd.stat |=  RX_BD_EMPTY;
473 		ethoc_write_bd(priv, entry, &bd);
474 		if (++priv->cur_rx == priv->num_rx)
475 			priv->cur_rx = 0;
476 	}
477 
478 	return count;
479 }
480 
481 static void ethoc_update_tx_stats(struct ethoc *dev, struct ethoc_bd *bd)
482 {
483 	struct net_device *netdev = dev->netdev;
484 
485 	if (bd->stat & TX_BD_LC) {
486 		dev_err(&netdev->dev, "TX: late collision\n");
487 		netdev->stats.tx_window_errors++;
488 	}
489 
490 	if (bd->stat & TX_BD_RL) {
491 		dev_err(&netdev->dev, "TX: retransmit limit\n");
492 		netdev->stats.tx_aborted_errors++;
493 	}
494 
495 	if (bd->stat & TX_BD_UR) {
496 		dev_err(&netdev->dev, "TX: underrun\n");
497 		netdev->stats.tx_fifo_errors++;
498 	}
499 
500 	if (bd->stat & TX_BD_CS) {
501 		dev_err(&netdev->dev, "TX: carrier sense lost\n");
502 		netdev->stats.tx_carrier_errors++;
503 	}
504 
505 	if (bd->stat & TX_BD_STATS)
506 		netdev->stats.tx_errors++;
507 
508 	netdev->stats.collisions += (bd->stat >> 4) & 0xf;
509 	netdev->stats.tx_bytes += bd->stat >> 16;
510 	netdev->stats.tx_packets++;
511 }
512 
513 static int ethoc_tx(struct net_device *dev, int limit)
514 {
515 	struct ethoc *priv = netdev_priv(dev);
516 	int count;
517 	struct ethoc_bd bd;
518 
519 	for (count = 0; count < limit; ++count) {
520 		unsigned int entry;
521 
522 		entry = priv->dty_tx & (priv->num_tx-1);
523 
524 		ethoc_read_bd(priv, entry, &bd);
525 
526 		if (bd.stat & TX_BD_READY || (priv->dty_tx == priv->cur_tx)) {
527 			ethoc_ack_irq(priv, INT_MASK_TX);
528 			/* If interrupt came in between reading in the BD
529 			 * and clearing the interrupt source, then we risk
530 			 * missing the event as the TX interrupt won't trigger
531 			 * right away when we reenable it; hence, check
532 			 * BD_EMPTY here again to make sure there isn't such an
533 			 * event pending...
534 			 */
535 			ethoc_read_bd(priv, entry, &bd);
536 			if (bd.stat & TX_BD_READY ||
537 			    (priv->dty_tx == priv->cur_tx))
538 				break;
539 		}
540 
541 		ethoc_update_tx_stats(priv, &bd);
542 		priv->dty_tx++;
543 	}
544 
545 	if ((priv->cur_tx - priv->dty_tx) <= (priv->num_tx / 2))
546 		netif_wake_queue(dev);
547 
548 	return count;
549 }
550 
551 static irqreturn_t ethoc_interrupt(int irq, void *dev_id)
552 {
553 	struct net_device *dev = dev_id;
554 	struct ethoc *priv = netdev_priv(dev);
555 	u32 pending;
556 	u32 mask;
557 
558 	/* Figure out what triggered the interrupt...
559 	 * The tricky bit here is that the interrupt source bits get
560 	 * set in INT_SOURCE for an event regardless of whether that
561 	 * event is masked or not.  Thus, in order to figure out what
562 	 * triggered the interrupt, we need to remove the sources
563 	 * for all events that are currently masked.  This behaviour
564 	 * is not particularly well documented but reasonable...
565 	 */
566 	mask = ethoc_read(priv, INT_MASK);
567 	pending = ethoc_read(priv, INT_SOURCE);
568 	pending &= mask;
569 
570 	if (unlikely(pending == 0))
571 		return IRQ_NONE;
572 
573 	ethoc_ack_irq(priv, pending);
574 
575 	/* We always handle the dropped packet interrupt */
576 	if (pending & INT_MASK_BUSY) {
577 		dev_err(&dev->dev, "packet dropped\n");
578 		dev->stats.rx_dropped++;
579 	}
580 
581 	/* Handle receive/transmit event by switching to polling */
582 	if (pending & (INT_MASK_TX | INT_MASK_RX)) {
583 		ethoc_disable_irq(priv, INT_MASK_TX | INT_MASK_RX);
584 		napi_schedule(&priv->napi);
585 	}
586 
587 	return IRQ_HANDLED;
588 }
589 
590 static int ethoc_get_mac_address(struct net_device *dev, void *addr)
591 {
592 	struct ethoc *priv = netdev_priv(dev);
593 	u8 *mac = (u8 *)addr;
594 	u32 reg;
595 
596 	reg = ethoc_read(priv, MAC_ADDR0);
597 	mac[2] = (reg >> 24) & 0xff;
598 	mac[3] = (reg >> 16) & 0xff;
599 	mac[4] = (reg >>  8) & 0xff;
600 	mac[5] = (reg >>  0) & 0xff;
601 
602 	reg = ethoc_read(priv, MAC_ADDR1);
603 	mac[0] = (reg >>  8) & 0xff;
604 	mac[1] = (reg >>  0) & 0xff;
605 
606 	return 0;
607 }
608 
609 static int ethoc_poll(struct napi_struct *napi, int budget)
610 {
611 	struct ethoc *priv = container_of(napi, struct ethoc, napi);
612 	int rx_work_done = 0;
613 	int tx_work_done = 0;
614 
615 	rx_work_done = ethoc_rx(priv->netdev, budget);
616 	tx_work_done = ethoc_tx(priv->netdev, budget);
617 
618 	if (rx_work_done < budget && tx_work_done < budget) {
619 		napi_complete(napi);
620 		ethoc_enable_irq(priv, INT_MASK_TX | INT_MASK_RX);
621 	}
622 
623 	return rx_work_done;
624 }
625 
626 static int ethoc_mdio_read(struct mii_bus *bus, int phy, int reg)
627 {
628 	struct ethoc *priv = bus->priv;
629 	int i;
630 
631 	ethoc_write(priv, MIIADDRESS, MIIADDRESS_ADDR(phy, reg));
632 	ethoc_write(priv, MIICOMMAND, MIICOMMAND_READ);
633 
634 	for (i = 0; i < 5; i++) {
635 		u32 status = ethoc_read(priv, MIISTATUS);
636 		if (!(status & MIISTATUS_BUSY)) {
637 			u32 data = ethoc_read(priv, MIIRX_DATA);
638 			/* reset MII command register */
639 			ethoc_write(priv, MIICOMMAND, 0);
640 			return data;
641 		}
642 		usleep_range(100, 200);
643 	}
644 
645 	return -EBUSY;
646 }
647 
648 static int ethoc_mdio_write(struct mii_bus *bus, int phy, int reg, u16 val)
649 {
650 	struct ethoc *priv = bus->priv;
651 	int i;
652 
653 	ethoc_write(priv, MIIADDRESS, MIIADDRESS_ADDR(phy, reg));
654 	ethoc_write(priv, MIITX_DATA, val);
655 	ethoc_write(priv, MIICOMMAND, MIICOMMAND_WRITE);
656 
657 	for (i = 0; i < 5; i++) {
658 		u32 stat = ethoc_read(priv, MIISTATUS);
659 		if (!(stat & MIISTATUS_BUSY)) {
660 			/* reset MII command register */
661 			ethoc_write(priv, MIICOMMAND, 0);
662 			return 0;
663 		}
664 		usleep_range(100, 200);
665 	}
666 
667 	return -EBUSY;
668 }
669 
670 static void ethoc_mdio_poll(struct net_device *dev)
671 {
672 }
673 
674 static int ethoc_mdio_probe(struct net_device *dev)
675 {
676 	struct ethoc *priv = netdev_priv(dev);
677 	struct phy_device *phy;
678 	int err;
679 
680 	if (priv->phy_id != -1)
681 		phy = priv->mdio->phy_map[priv->phy_id];
682 	else
683 		phy = phy_find_first(priv->mdio);
684 
685 	if (!phy) {
686 		dev_err(&dev->dev, "no PHY found\n");
687 		return -ENXIO;
688 	}
689 
690 	err = phy_connect_direct(dev, phy, ethoc_mdio_poll,
691 				 PHY_INTERFACE_MODE_GMII);
692 	if (err) {
693 		dev_err(&dev->dev, "could not attach to PHY\n");
694 		return err;
695 	}
696 
697 	priv->phy = phy;
698 	phy->advertising &= ~(ADVERTISED_1000baseT_Full |
699 			      ADVERTISED_1000baseT_Half);
700 	phy->supported &= ~(SUPPORTED_1000baseT_Full |
701 			    SUPPORTED_1000baseT_Half);
702 
703 	return 0;
704 }
705 
706 static int ethoc_open(struct net_device *dev)
707 {
708 	struct ethoc *priv = netdev_priv(dev);
709 	int ret;
710 
711 	ret = request_irq(dev->irq, ethoc_interrupt, IRQF_SHARED,
712 			dev->name, dev);
713 	if (ret)
714 		return ret;
715 
716 	ethoc_init_ring(priv, dev->mem_start);
717 	ethoc_reset(priv);
718 
719 	if (netif_queue_stopped(dev)) {
720 		dev_dbg(&dev->dev, " resuming queue\n");
721 		netif_wake_queue(dev);
722 	} else {
723 		dev_dbg(&dev->dev, " starting queue\n");
724 		netif_start_queue(dev);
725 	}
726 
727 	phy_start(priv->phy);
728 	napi_enable(&priv->napi);
729 
730 	if (netif_msg_ifup(priv)) {
731 		dev_info(&dev->dev, "I/O: %08lx Memory: %08lx-%08lx\n",
732 				dev->base_addr, dev->mem_start, dev->mem_end);
733 	}
734 
735 	return 0;
736 }
737 
738 static int ethoc_stop(struct net_device *dev)
739 {
740 	struct ethoc *priv = netdev_priv(dev);
741 
742 	napi_disable(&priv->napi);
743 
744 	if (priv->phy)
745 		phy_stop(priv->phy);
746 
747 	ethoc_disable_rx_and_tx(priv);
748 	free_irq(dev->irq, dev);
749 
750 	if (!netif_queue_stopped(dev))
751 		netif_stop_queue(dev);
752 
753 	return 0;
754 }
755 
756 static int ethoc_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
757 {
758 	struct ethoc *priv = netdev_priv(dev);
759 	struct mii_ioctl_data *mdio = if_mii(ifr);
760 	struct phy_device *phy = NULL;
761 
762 	if (!netif_running(dev))
763 		return -EINVAL;
764 
765 	if (cmd != SIOCGMIIPHY) {
766 		if (mdio->phy_id >= PHY_MAX_ADDR)
767 			return -ERANGE;
768 
769 		phy = priv->mdio->phy_map[mdio->phy_id];
770 		if (!phy)
771 			return -ENODEV;
772 	} else {
773 		phy = priv->phy;
774 	}
775 
776 	return phy_mii_ioctl(phy, ifr, cmd);
777 }
778 
779 static void ethoc_do_set_mac_address(struct net_device *dev)
780 {
781 	struct ethoc *priv = netdev_priv(dev);
782 	unsigned char *mac = dev->dev_addr;
783 
784 	ethoc_write(priv, MAC_ADDR0, (mac[2] << 24) | (mac[3] << 16) |
785 				     (mac[4] <<  8) | (mac[5] <<  0));
786 	ethoc_write(priv, MAC_ADDR1, (mac[0] <<  8) | (mac[1] <<  0));
787 }
788 
789 static int ethoc_set_mac_address(struct net_device *dev, void *p)
790 {
791 	const struct sockaddr *addr = p;
792 
793 	if (!is_valid_ether_addr(addr->sa_data))
794 		return -EADDRNOTAVAIL;
795 	memcpy(dev->dev_addr, addr->sa_data, ETH_ALEN);
796 	ethoc_do_set_mac_address(dev);
797 	return 0;
798 }
799 
800 static void ethoc_set_multicast_list(struct net_device *dev)
801 {
802 	struct ethoc *priv = netdev_priv(dev);
803 	u32 mode = ethoc_read(priv, MODER);
804 	struct netdev_hw_addr *ha;
805 	u32 hash[2] = { 0, 0 };
806 
807 	/* set loopback mode if requested */
808 	if (dev->flags & IFF_LOOPBACK)
809 		mode |=  MODER_LOOP;
810 	else
811 		mode &= ~MODER_LOOP;
812 
813 	/* receive broadcast frames if requested */
814 	if (dev->flags & IFF_BROADCAST)
815 		mode &= ~MODER_BRO;
816 	else
817 		mode |=  MODER_BRO;
818 
819 	/* enable promiscuous mode if requested */
820 	if (dev->flags & IFF_PROMISC)
821 		mode |=  MODER_PRO;
822 	else
823 		mode &= ~MODER_PRO;
824 
825 	ethoc_write(priv, MODER, mode);
826 
827 	/* receive multicast frames */
828 	if (dev->flags & IFF_ALLMULTI) {
829 		hash[0] = 0xffffffff;
830 		hash[1] = 0xffffffff;
831 	} else {
832 		netdev_for_each_mc_addr(ha, dev) {
833 			u32 crc = ether_crc(ETH_ALEN, ha->addr);
834 			int bit = (crc >> 26) & 0x3f;
835 			hash[bit >> 5] |= 1 << (bit & 0x1f);
836 		}
837 	}
838 
839 	ethoc_write(priv, ETH_HASH0, hash[0]);
840 	ethoc_write(priv, ETH_HASH1, hash[1]);
841 }
842 
843 static int ethoc_change_mtu(struct net_device *dev, int new_mtu)
844 {
845 	return -ENOSYS;
846 }
847 
848 static void ethoc_tx_timeout(struct net_device *dev)
849 {
850 	struct ethoc *priv = netdev_priv(dev);
851 	u32 pending = ethoc_read(priv, INT_SOURCE);
852 	if (likely(pending))
853 		ethoc_interrupt(dev->irq, dev);
854 }
855 
856 static netdev_tx_t ethoc_start_xmit(struct sk_buff *skb, struct net_device *dev)
857 {
858 	struct ethoc *priv = netdev_priv(dev);
859 	struct ethoc_bd bd;
860 	unsigned int entry;
861 	void *dest;
862 
863 	if (unlikely(skb->len > ETHOC_BUFSIZ)) {
864 		dev->stats.tx_errors++;
865 		goto out;
866 	}
867 
868 	entry = priv->cur_tx % priv->num_tx;
869 	spin_lock_irq(&priv->lock);
870 	priv->cur_tx++;
871 
872 	ethoc_read_bd(priv, entry, &bd);
873 	if (unlikely(skb->len < ETHOC_ZLEN))
874 		bd.stat |=  TX_BD_PAD;
875 	else
876 		bd.stat &= ~TX_BD_PAD;
877 
878 	dest = priv->vma[entry];
879 	memcpy_toio(dest, skb->data, skb->len);
880 
881 	bd.stat &= ~(TX_BD_STATS | TX_BD_LEN_MASK);
882 	bd.stat |= TX_BD_LEN(skb->len);
883 	ethoc_write_bd(priv, entry, &bd);
884 
885 	bd.stat |= TX_BD_READY;
886 	ethoc_write_bd(priv, entry, &bd);
887 
888 	if (priv->cur_tx == (priv->dty_tx + priv->num_tx)) {
889 		dev_dbg(&dev->dev, "stopping queue\n");
890 		netif_stop_queue(dev);
891 	}
892 
893 	spin_unlock_irq(&priv->lock);
894 	skb_tx_timestamp(skb);
895 out:
896 	dev_kfree_skb(skb);
897 	return NETDEV_TX_OK;
898 }
899 
900 static int ethoc_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
901 {
902 	struct ethoc *priv = netdev_priv(dev);
903 	struct phy_device *phydev = priv->phy;
904 
905 	if (!phydev)
906 		return -EOPNOTSUPP;
907 
908 	return phy_ethtool_gset(phydev, cmd);
909 }
910 
911 static int ethoc_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
912 {
913 	struct ethoc *priv = netdev_priv(dev);
914 	struct phy_device *phydev = priv->phy;
915 
916 	if (!phydev)
917 		return -EOPNOTSUPP;
918 
919 	return phy_ethtool_sset(phydev, cmd);
920 }
921 
922 static int ethoc_get_regs_len(struct net_device *netdev)
923 {
924 	return ETH_END;
925 }
926 
927 static void ethoc_get_regs(struct net_device *dev, struct ethtool_regs *regs,
928 			   void *p)
929 {
930 	struct ethoc *priv = netdev_priv(dev);
931 	u32 *regs_buff = p;
932 	unsigned i;
933 
934 	regs->version = 0;
935 	for (i = 0; i < ETH_END / sizeof(u32); ++i)
936 		regs_buff[i] = ethoc_read(priv, i * sizeof(u32));
937 }
938 
939 static void ethoc_get_ringparam(struct net_device *dev,
940 				struct ethtool_ringparam *ring)
941 {
942 	struct ethoc *priv = netdev_priv(dev);
943 
944 	ring->rx_max_pending = priv->num_bd - 1;
945 	ring->rx_mini_max_pending = 0;
946 	ring->rx_jumbo_max_pending = 0;
947 	ring->tx_max_pending = priv->num_bd - 1;
948 
949 	ring->rx_pending = priv->num_rx;
950 	ring->rx_mini_pending = 0;
951 	ring->rx_jumbo_pending = 0;
952 	ring->tx_pending = priv->num_tx;
953 }
954 
955 static int ethoc_set_ringparam(struct net_device *dev,
956 			       struct ethtool_ringparam *ring)
957 {
958 	struct ethoc *priv = netdev_priv(dev);
959 
960 	if (ring->tx_pending < 1 || ring->rx_pending < 1 ||
961 	    ring->tx_pending + ring->rx_pending > priv->num_bd)
962 		return -EINVAL;
963 	if (ring->rx_mini_pending || ring->rx_jumbo_pending)
964 		return -EINVAL;
965 
966 	if (netif_running(dev)) {
967 		netif_tx_disable(dev);
968 		ethoc_disable_rx_and_tx(priv);
969 		ethoc_disable_irq(priv, INT_MASK_TX | INT_MASK_RX);
970 		synchronize_irq(dev->irq);
971 	}
972 
973 	priv->num_tx = rounddown_pow_of_two(ring->tx_pending);
974 	priv->num_rx = ring->rx_pending;
975 	ethoc_init_ring(priv, dev->mem_start);
976 
977 	if (netif_running(dev)) {
978 		ethoc_enable_irq(priv, INT_MASK_TX | INT_MASK_RX);
979 		ethoc_enable_rx_and_tx(priv);
980 		netif_wake_queue(dev);
981 	}
982 	return 0;
983 }
984 
985 const struct ethtool_ops ethoc_ethtool_ops = {
986 	.get_settings = ethoc_get_settings,
987 	.set_settings = ethoc_set_settings,
988 	.get_regs_len = ethoc_get_regs_len,
989 	.get_regs = ethoc_get_regs,
990 	.get_link = ethtool_op_get_link,
991 	.get_ringparam = ethoc_get_ringparam,
992 	.set_ringparam = ethoc_set_ringparam,
993 	.get_ts_info = ethtool_op_get_ts_info,
994 };
995 
996 static const struct net_device_ops ethoc_netdev_ops = {
997 	.ndo_open = ethoc_open,
998 	.ndo_stop = ethoc_stop,
999 	.ndo_do_ioctl = ethoc_ioctl,
1000 	.ndo_set_mac_address = ethoc_set_mac_address,
1001 	.ndo_set_rx_mode = ethoc_set_multicast_list,
1002 	.ndo_change_mtu = ethoc_change_mtu,
1003 	.ndo_tx_timeout = ethoc_tx_timeout,
1004 	.ndo_start_xmit = ethoc_start_xmit,
1005 };
1006 
1007 /**
1008  * ethoc_probe - initialize OpenCores ethernet MAC
1009  * pdev:	platform device
1010  */
1011 static int ethoc_probe(struct platform_device *pdev)
1012 {
1013 	struct net_device *netdev = NULL;
1014 	struct resource *res = NULL;
1015 	struct resource *mmio = NULL;
1016 	struct resource *mem = NULL;
1017 	struct ethoc *priv = NULL;
1018 	unsigned int phy;
1019 	int num_bd;
1020 	int ret = 0;
1021 	bool random_mac = false;
1022 	struct ethoc_platform_data *pdata = dev_get_platdata(&pdev->dev);
1023 	u32 eth_clkfreq = pdata ? pdata->eth_clkfreq : 0;
1024 
1025 	/* allocate networking device */
1026 	netdev = alloc_etherdev(sizeof(struct ethoc));
1027 	if (!netdev) {
1028 		ret = -ENOMEM;
1029 		goto out;
1030 	}
1031 
1032 	SET_NETDEV_DEV(netdev, &pdev->dev);
1033 	platform_set_drvdata(pdev, netdev);
1034 
1035 	/* obtain I/O memory space */
1036 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1037 	if (!res) {
1038 		dev_err(&pdev->dev, "cannot obtain I/O memory space\n");
1039 		ret = -ENXIO;
1040 		goto free;
1041 	}
1042 
1043 	mmio = devm_request_mem_region(&pdev->dev, res->start,
1044 			resource_size(res), res->name);
1045 	if (!mmio) {
1046 		dev_err(&pdev->dev, "cannot request I/O memory space\n");
1047 		ret = -ENXIO;
1048 		goto free;
1049 	}
1050 
1051 	netdev->base_addr = mmio->start;
1052 
1053 	/* obtain buffer memory space */
1054 	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1055 	if (res) {
1056 		mem = devm_request_mem_region(&pdev->dev, res->start,
1057 			resource_size(res), res->name);
1058 		if (!mem) {
1059 			dev_err(&pdev->dev, "cannot request memory space\n");
1060 			ret = -ENXIO;
1061 			goto free;
1062 		}
1063 
1064 		netdev->mem_start = mem->start;
1065 		netdev->mem_end   = mem->end;
1066 	}
1067 
1068 
1069 	/* obtain device IRQ number */
1070 	res = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1071 	if (!res) {
1072 		dev_err(&pdev->dev, "cannot obtain IRQ\n");
1073 		ret = -ENXIO;
1074 		goto free;
1075 	}
1076 
1077 	netdev->irq = res->start;
1078 
1079 	/* setup driver-private data */
1080 	priv = netdev_priv(netdev);
1081 	priv->netdev = netdev;
1082 	priv->dma_alloc = 0;
1083 	priv->io_region_size = resource_size(mmio);
1084 
1085 	priv->iobase = devm_ioremap_nocache(&pdev->dev, netdev->base_addr,
1086 			resource_size(mmio));
1087 	if (!priv->iobase) {
1088 		dev_err(&pdev->dev, "cannot remap I/O memory space\n");
1089 		ret = -ENXIO;
1090 		goto error;
1091 	}
1092 
1093 	if (netdev->mem_end) {
1094 		priv->membase = devm_ioremap_nocache(&pdev->dev,
1095 			netdev->mem_start, resource_size(mem));
1096 		if (!priv->membase) {
1097 			dev_err(&pdev->dev, "cannot remap memory space\n");
1098 			ret = -ENXIO;
1099 			goto error;
1100 		}
1101 	} else {
1102 		/* Allocate buffer memory */
1103 		priv->membase = dmam_alloc_coherent(&pdev->dev,
1104 			buffer_size, (void *)&netdev->mem_start,
1105 			GFP_KERNEL);
1106 		if (!priv->membase) {
1107 			dev_err(&pdev->dev, "cannot allocate %dB buffer\n",
1108 				buffer_size);
1109 			ret = -ENOMEM;
1110 			goto error;
1111 		}
1112 		netdev->mem_end = netdev->mem_start + buffer_size;
1113 		priv->dma_alloc = buffer_size;
1114 	}
1115 
1116 	priv->big_endian = pdata ? pdata->big_endian :
1117 		of_device_is_big_endian(pdev->dev.of_node);
1118 
1119 	/* calculate the number of TX/RX buffers, maximum 128 supported */
1120 	num_bd = min_t(unsigned int,
1121 		128, (netdev->mem_end - netdev->mem_start + 1) / ETHOC_BUFSIZ);
1122 	if (num_bd < 4) {
1123 		ret = -ENODEV;
1124 		goto error;
1125 	}
1126 	priv->num_bd = num_bd;
1127 	/* num_tx must be a power of two */
1128 	priv->num_tx = rounddown_pow_of_two(num_bd >> 1);
1129 	priv->num_rx = num_bd - priv->num_tx;
1130 
1131 	dev_dbg(&pdev->dev, "ethoc: num_tx: %d num_rx: %d\n",
1132 		priv->num_tx, priv->num_rx);
1133 
1134 	priv->vma = devm_kzalloc(&pdev->dev, num_bd*sizeof(void *), GFP_KERNEL);
1135 	if (!priv->vma) {
1136 		ret = -ENOMEM;
1137 		goto error;
1138 	}
1139 
1140 	/* Allow the platform setup code to pass in a MAC address. */
1141 	if (pdata) {
1142 		memcpy(netdev->dev_addr, pdata->hwaddr, IFHWADDRLEN);
1143 		priv->phy_id = pdata->phy_id;
1144 	} else {
1145 		const uint8_t *mac;
1146 
1147 		mac = of_get_property(pdev->dev.of_node,
1148 				      "local-mac-address",
1149 				      NULL);
1150 		if (mac)
1151 			memcpy(netdev->dev_addr, mac, IFHWADDRLEN);
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 		ethoc_get_mac_address(netdev, netdev->dev_addr);
1160 
1161 	/* Check the MAC again for validity, if it still isn't choose and
1162 	 * program a random one.
1163 	 */
1164 	if (!is_valid_ether_addr(netdev->dev_addr)) {
1165 		eth_random_addr(netdev->dev_addr);
1166 		random_mac = true;
1167 	}
1168 
1169 	ethoc_do_set_mac_address(netdev);
1170 
1171 	if (random_mac)
1172 		netdev->addr_assign_type = NET_ADDR_RANDOM;
1173 
1174 	/* Allow the platform setup code to adjust MII management bus clock. */
1175 	if (!eth_clkfreq) {
1176 		struct clk *clk = devm_clk_get(&pdev->dev, NULL);
1177 
1178 		if (!IS_ERR(clk)) {
1179 			priv->clk = clk;
1180 			clk_prepare_enable(clk);
1181 			eth_clkfreq = clk_get_rate(clk);
1182 		}
1183 	}
1184 	if (eth_clkfreq) {
1185 		u32 clkdiv = MIIMODER_CLKDIV(eth_clkfreq / 2500000 + 1);
1186 
1187 		if (!clkdiv)
1188 			clkdiv = 2;
1189 		dev_dbg(&pdev->dev, "setting MII clkdiv to %u\n", clkdiv);
1190 		ethoc_write(priv, MIIMODER,
1191 			    (ethoc_read(priv, MIIMODER) & MIIMODER_NOPRE) |
1192 			    clkdiv);
1193 	}
1194 
1195 	/* register MII bus */
1196 	priv->mdio = mdiobus_alloc();
1197 	if (!priv->mdio) {
1198 		ret = -ENOMEM;
1199 		goto free;
1200 	}
1201 
1202 	priv->mdio->name = "ethoc-mdio";
1203 	snprintf(priv->mdio->id, MII_BUS_ID_SIZE, "%s-%d",
1204 			priv->mdio->name, pdev->id);
1205 	priv->mdio->read = ethoc_mdio_read;
1206 	priv->mdio->write = ethoc_mdio_write;
1207 	priv->mdio->priv = priv;
1208 
1209 	priv->mdio->irq = kmalloc(sizeof(int) * PHY_MAX_ADDR, GFP_KERNEL);
1210 	if (!priv->mdio->irq) {
1211 		ret = -ENOMEM;
1212 		goto free_mdio;
1213 	}
1214 
1215 	for (phy = 0; phy < PHY_MAX_ADDR; phy++)
1216 		priv->mdio->irq[phy] = PHY_POLL;
1217 
1218 	ret = mdiobus_register(priv->mdio);
1219 	if (ret) {
1220 		dev_err(&netdev->dev, "failed to register MDIO bus\n");
1221 		goto free_mdio;
1222 	}
1223 
1224 	ret = ethoc_mdio_probe(netdev);
1225 	if (ret) {
1226 		dev_err(&netdev->dev, "failed to probe MDIO bus\n");
1227 		goto error;
1228 	}
1229 
1230 	/* setup the net_device structure */
1231 	netdev->netdev_ops = &ethoc_netdev_ops;
1232 	netdev->watchdog_timeo = ETHOC_TIMEOUT;
1233 	netdev->features |= 0;
1234 	netdev->ethtool_ops = &ethoc_ethtool_ops;
1235 
1236 	/* setup NAPI */
1237 	netif_napi_add(netdev, &priv->napi, ethoc_poll, 64);
1238 
1239 	spin_lock_init(&priv->lock);
1240 
1241 	ret = register_netdev(netdev);
1242 	if (ret < 0) {
1243 		dev_err(&netdev->dev, "failed to register interface\n");
1244 		goto error2;
1245 	}
1246 
1247 	goto out;
1248 
1249 error2:
1250 	netif_napi_del(&priv->napi);
1251 error:
1252 	mdiobus_unregister(priv->mdio);
1253 free_mdio:
1254 	kfree(priv->mdio->irq);
1255 	mdiobus_free(priv->mdio);
1256 free:
1257 	if (priv->clk)
1258 		clk_disable_unprepare(priv->clk);
1259 	free_netdev(netdev);
1260 out:
1261 	return ret;
1262 }
1263 
1264 /**
1265  * ethoc_remove - shutdown OpenCores ethernet MAC
1266  * @pdev:	platform device
1267  */
1268 static int ethoc_remove(struct platform_device *pdev)
1269 {
1270 	struct net_device *netdev = platform_get_drvdata(pdev);
1271 	struct ethoc *priv = netdev_priv(netdev);
1272 
1273 	if (netdev) {
1274 		netif_napi_del(&priv->napi);
1275 		phy_disconnect(priv->phy);
1276 		priv->phy = NULL;
1277 
1278 		if (priv->mdio) {
1279 			mdiobus_unregister(priv->mdio);
1280 			kfree(priv->mdio->irq);
1281 			mdiobus_free(priv->mdio);
1282 		}
1283 		if (priv->clk)
1284 			clk_disable_unprepare(priv->clk);
1285 		unregister_netdev(netdev);
1286 		free_netdev(netdev);
1287 	}
1288 
1289 	return 0;
1290 }
1291 
1292 #ifdef CONFIG_PM
1293 static int ethoc_suspend(struct platform_device *pdev, pm_message_t state)
1294 {
1295 	return -ENOSYS;
1296 }
1297 
1298 static int ethoc_resume(struct platform_device *pdev)
1299 {
1300 	return -ENOSYS;
1301 }
1302 #else
1303 # define ethoc_suspend NULL
1304 # define ethoc_resume  NULL
1305 #endif
1306 
1307 static const struct of_device_id ethoc_match[] = {
1308 	{ .compatible = "opencores,ethoc", },
1309 	{},
1310 };
1311 MODULE_DEVICE_TABLE(of, ethoc_match);
1312 
1313 static struct platform_driver ethoc_driver = {
1314 	.probe   = ethoc_probe,
1315 	.remove  = ethoc_remove,
1316 	.suspend = ethoc_suspend,
1317 	.resume  = ethoc_resume,
1318 	.driver  = {
1319 		.name = "ethoc",
1320 		.of_match_table = ethoc_match,
1321 	},
1322 };
1323 
1324 module_platform_driver(ethoc_driver);
1325 
1326 MODULE_AUTHOR("Thierry Reding <thierry.reding@avionic-design.de>");
1327 MODULE_DESCRIPTION("OpenCores Ethernet MAC driver");
1328 MODULE_LICENSE("GPL v2");
1329 
1330