1 /*
2  * Xilinx EmacLite Linux driver for the Xilinx Ethernet MAC Lite device.
3  *
4  * This is a new flat driver which is based on the original emac_lite
5  * driver from John Williams <john.williams@xilinx.com>.
6  *
7  * 2007 - 2013 (c) Xilinx, Inc.
8  *
9  * This program is free software; you can redistribute it and/or modify it
10  * under the terms of the GNU General Public License as published by the
11  * Free Software Foundation; either version 2 of the License, or (at your
12  * option) any later version.
13  */
14 
15 #include <linux/module.h>
16 #include <linux/uaccess.h>
17 #include <linux/netdevice.h>
18 #include <linux/etherdevice.h>
19 #include <linux/skbuff.h>
20 #include <linux/io.h>
21 #include <linux/slab.h>
22 #include <linux/of_address.h>
23 #include <linux/of_device.h>
24 #include <linux/of_platform.h>
25 #include <linux/of_mdio.h>
26 #include <linux/of_net.h>
27 #include <linux/phy.h>
28 #include <linux/interrupt.h>
29 
30 #define DRIVER_NAME "xilinx_emaclite"
31 
32 /* Register offsets for the EmacLite Core */
33 #define XEL_TXBUFF_OFFSET	0x0		/* Transmit Buffer */
34 #define XEL_MDIOADDR_OFFSET	0x07E4		/* MDIO Address Register */
35 #define XEL_MDIOWR_OFFSET	0x07E8		/* MDIO Write Data Register */
36 #define XEL_MDIORD_OFFSET	0x07EC		/* MDIO Read Data Register */
37 #define XEL_MDIOCTRL_OFFSET	0x07F0		/* MDIO Control Register */
38 #define XEL_GIER_OFFSET		0x07F8		/* GIE Register */
39 #define XEL_TSR_OFFSET		0x07FC		/* Tx status */
40 #define XEL_TPLR_OFFSET		0x07F4		/* Tx packet length */
41 
42 #define XEL_RXBUFF_OFFSET	0x1000		/* Receive Buffer */
43 #define XEL_RPLR_OFFSET		0x100C		/* Rx packet length */
44 #define XEL_RSR_OFFSET		0x17FC		/* Rx status */
45 
46 #define XEL_BUFFER_OFFSET	0x0800		/* Next Tx/Rx buffer's offset */
47 
48 /* MDIO Address Register Bit Masks */
49 #define XEL_MDIOADDR_REGADR_MASK  0x0000001F	/* Register Address */
50 #define XEL_MDIOADDR_PHYADR_MASK  0x000003E0	/* PHY Address */
51 #define XEL_MDIOADDR_PHYADR_SHIFT 5
52 #define XEL_MDIOADDR_OP_MASK	  0x00000400	/* RD/WR Operation */
53 
54 /* MDIO Write Data Register Bit Masks */
55 #define XEL_MDIOWR_WRDATA_MASK	  0x0000FFFF	/* Data to be Written */
56 
57 /* MDIO Read Data Register Bit Masks */
58 #define XEL_MDIORD_RDDATA_MASK	  0x0000FFFF	/* Data to be Read */
59 
60 /* MDIO Control Register Bit Masks */
61 #define XEL_MDIOCTRL_MDIOSTS_MASK 0x00000001	/* MDIO Status Mask */
62 #define XEL_MDIOCTRL_MDIOEN_MASK  0x00000008	/* MDIO Enable */
63 
64 /* Global Interrupt Enable Register (GIER) Bit Masks */
65 #define XEL_GIER_GIE_MASK	0x80000000	/* Global Enable */
66 
67 /* Transmit Status Register (TSR) Bit Masks */
68 #define XEL_TSR_XMIT_BUSY_MASK	 0x00000001	/* Tx complete */
69 #define XEL_TSR_PROGRAM_MASK	 0x00000002	/* Program the MAC address */
70 #define XEL_TSR_XMIT_IE_MASK	 0x00000008	/* Tx interrupt enable bit */
71 #define XEL_TSR_XMIT_ACTIVE_MASK 0x80000000	/* Buffer is active, SW bit
72 						 * only. This is not documented
73 						 * in the HW spec */
74 
75 /* Define for programming the MAC address into the EmacLite */
76 #define XEL_TSR_PROG_MAC_ADDR	(XEL_TSR_XMIT_BUSY_MASK | XEL_TSR_PROGRAM_MASK)
77 
78 /* Receive Status Register (RSR) */
79 #define XEL_RSR_RECV_DONE_MASK	0x00000001	/* Rx complete */
80 #define XEL_RSR_RECV_IE_MASK	0x00000008	/* Rx interrupt enable bit */
81 
82 /* Transmit Packet Length Register (TPLR) */
83 #define XEL_TPLR_LENGTH_MASK	0x0000FFFF	/* Tx packet length */
84 
85 /* Receive Packet Length Register (RPLR) */
86 #define XEL_RPLR_LENGTH_MASK	0x0000FFFF	/* Rx packet length */
87 
88 #define XEL_HEADER_OFFSET	12		/* Offset to length field */
89 #define XEL_HEADER_SHIFT	16		/* Shift value for length */
90 
91 /* General Ethernet Definitions */
92 #define XEL_ARP_PACKET_SIZE		28	/* Max ARP packet size */
93 #define XEL_HEADER_IP_LENGTH_OFFSET	16	/* IP Length Offset */
94 
95 
96 
97 #define TX_TIMEOUT		(60*HZ)		/* Tx timeout is 60 seconds. */
98 #define ALIGNMENT		4
99 
100 /* BUFFER_ALIGN(adr) calculates the number of bytes to the next alignment. */
101 #define BUFFER_ALIGN(adr) ((ALIGNMENT - ((u32) adr)) % ALIGNMENT)
102 
103 /**
104  * struct net_local - Our private per device data
105  * @ndev:		instance of the network device
106  * @tx_ping_pong:	indicates whether Tx Pong buffer is configured in HW
107  * @rx_ping_pong:	indicates whether Rx Pong buffer is configured in HW
108  * @next_tx_buf_to_use:	next Tx buffer to write to
109  * @next_rx_buf_to_use:	next Rx buffer to read from
110  * @base_addr:		base address of the Emaclite device
111  * @reset_lock:		lock used for synchronization
112  * @deferred_skb:	holds an skb (for transmission at a later time) when the
113  *			Tx buffer is not free
114  * @phy_dev:		pointer to the PHY device
115  * @phy_node:		pointer to the PHY device node
116  * @mii_bus:		pointer to the MII bus
117  * @mdio_irqs:		IRQs table for MDIO bus
118  * @last_link:		last link status
119  * @has_mdio:		indicates whether MDIO is included in the HW
120  */
121 struct net_local {
122 
123 	struct net_device *ndev;
124 
125 	bool tx_ping_pong;
126 	bool rx_ping_pong;
127 	u32 next_tx_buf_to_use;
128 	u32 next_rx_buf_to_use;
129 	void __iomem *base_addr;
130 
131 	spinlock_t reset_lock;
132 	struct sk_buff *deferred_skb;
133 
134 	struct phy_device *phy_dev;
135 	struct device_node *phy_node;
136 
137 	struct mii_bus *mii_bus;
138 	int mdio_irqs[PHY_MAX_ADDR];
139 
140 	int last_link;
141 	bool has_mdio;
142 };
143 
144 
145 /*************************/
146 /* EmacLite driver calls */
147 /*************************/
148 
149 /**
150  * xemaclite_enable_interrupts - Enable the interrupts for the EmacLite device
151  * @drvdata:	Pointer to the Emaclite device private data
152  *
153  * This function enables the Tx and Rx interrupts for the Emaclite device along
154  * with the Global Interrupt Enable.
155  */
156 static void xemaclite_enable_interrupts(struct net_local *drvdata)
157 {
158 	u32 reg_data;
159 
160 	/* Enable the Tx interrupts for the first Buffer */
161 	reg_data = __raw_readl(drvdata->base_addr + XEL_TSR_OFFSET);
162 	__raw_writel(reg_data | XEL_TSR_XMIT_IE_MASK,
163 		     drvdata->base_addr + XEL_TSR_OFFSET);
164 
165 	/* Enable the Rx interrupts for the first buffer */
166 	__raw_writel(XEL_RSR_RECV_IE_MASK, drvdata->base_addr + XEL_RSR_OFFSET);
167 
168 	/* Enable the Global Interrupt Enable */
169 	__raw_writel(XEL_GIER_GIE_MASK, drvdata->base_addr + XEL_GIER_OFFSET);
170 }
171 
172 /**
173  * xemaclite_disable_interrupts - Disable the interrupts for the EmacLite device
174  * @drvdata:	Pointer to the Emaclite device private data
175  *
176  * This function disables the Tx and Rx interrupts for the Emaclite device,
177  * along with the Global Interrupt Enable.
178  */
179 static void xemaclite_disable_interrupts(struct net_local *drvdata)
180 {
181 	u32 reg_data;
182 
183 	/* Disable the Global Interrupt Enable */
184 	__raw_writel(XEL_GIER_GIE_MASK, drvdata->base_addr + XEL_GIER_OFFSET);
185 
186 	/* Disable the Tx interrupts for the first buffer */
187 	reg_data = __raw_readl(drvdata->base_addr + XEL_TSR_OFFSET);
188 	__raw_writel(reg_data & (~XEL_TSR_XMIT_IE_MASK),
189 		     drvdata->base_addr + XEL_TSR_OFFSET);
190 
191 	/* Disable the Rx interrupts for the first buffer */
192 	reg_data = __raw_readl(drvdata->base_addr + XEL_RSR_OFFSET);
193 	__raw_writel(reg_data & (~XEL_RSR_RECV_IE_MASK),
194 		     drvdata->base_addr + XEL_RSR_OFFSET);
195 }
196 
197 /**
198  * xemaclite_aligned_write - Write from 16-bit aligned to 32-bit aligned address
199  * @src_ptr:	Void pointer to the 16-bit aligned source address
200  * @dest_ptr:	Pointer to the 32-bit aligned destination address
201  * @length:	Number bytes to write from source to destination
202  *
203  * This function writes data from a 16-bit aligned buffer to a 32-bit aligned
204  * address in the EmacLite device.
205  */
206 static void xemaclite_aligned_write(void *src_ptr, u32 *dest_ptr,
207 				    unsigned length)
208 {
209 	u32 align_buffer;
210 	u32 *to_u32_ptr;
211 	u16 *from_u16_ptr, *to_u16_ptr;
212 
213 	to_u32_ptr = dest_ptr;
214 	from_u16_ptr = src_ptr;
215 	align_buffer = 0;
216 
217 	for (; length > 3; length -= 4) {
218 		to_u16_ptr = (u16 *)&align_buffer;
219 		*to_u16_ptr++ = *from_u16_ptr++;
220 		*to_u16_ptr++ = *from_u16_ptr++;
221 
222 		/* This barrier resolves occasional issues seen around
223 		 * cases where the data is not properly flushed out
224 		 * from the processor store buffers to the destination
225 		 * memory locations.
226 		 */
227 		wmb();
228 
229 		/* Output a word */
230 		*to_u32_ptr++ = align_buffer;
231 	}
232 	if (length) {
233 		u8 *from_u8_ptr, *to_u8_ptr;
234 
235 		/* Set up to output the remaining data */
236 		align_buffer = 0;
237 		to_u8_ptr = (u8 *) &align_buffer;
238 		from_u8_ptr = (u8 *) from_u16_ptr;
239 
240 		/* Output the remaining data */
241 		for (; length > 0; length--)
242 			*to_u8_ptr++ = *from_u8_ptr++;
243 
244 		/* This barrier resolves occasional issues seen around
245 		 * cases where the data is not properly flushed out
246 		 * from the processor store buffers to the destination
247 		 * memory locations.
248 		 */
249 		wmb();
250 		*to_u32_ptr = align_buffer;
251 	}
252 }
253 
254 /**
255  * xemaclite_aligned_read - Read from 32-bit aligned to 16-bit aligned buffer
256  * @src_ptr:	Pointer to the 32-bit aligned source address
257  * @dest_ptr:	Pointer to the 16-bit aligned destination address
258  * @length:	Number bytes to read from source to destination
259  *
260  * This function reads data from a 32-bit aligned address in the EmacLite device
261  * to a 16-bit aligned buffer.
262  */
263 static void xemaclite_aligned_read(u32 *src_ptr, u8 *dest_ptr,
264 				   unsigned length)
265 {
266 	u16 *to_u16_ptr, *from_u16_ptr;
267 	u32 *from_u32_ptr;
268 	u32 align_buffer;
269 
270 	from_u32_ptr = src_ptr;
271 	to_u16_ptr = (u16 *) dest_ptr;
272 
273 	for (; length > 3; length -= 4) {
274 		/* Copy each word into the temporary buffer */
275 		align_buffer = *from_u32_ptr++;
276 		from_u16_ptr = (u16 *)&align_buffer;
277 
278 		/* Read data from source */
279 		*to_u16_ptr++ = *from_u16_ptr++;
280 		*to_u16_ptr++ = *from_u16_ptr++;
281 	}
282 
283 	if (length) {
284 		u8 *to_u8_ptr, *from_u8_ptr;
285 
286 		/* Set up to read the remaining data */
287 		to_u8_ptr = (u8 *) to_u16_ptr;
288 		align_buffer = *from_u32_ptr++;
289 		from_u8_ptr = (u8 *) &align_buffer;
290 
291 		/* Read the remaining data */
292 		for (; length > 0; length--)
293 			*to_u8_ptr = *from_u8_ptr;
294 	}
295 }
296 
297 /**
298  * xemaclite_send_data - Send an Ethernet frame
299  * @drvdata:	Pointer to the Emaclite device private data
300  * @data:	Pointer to the data to be sent
301  * @byte_count:	Total frame size, including header
302  *
303  * This function checks if the Tx buffer of the Emaclite device is free to send
304  * data. If so, it fills the Tx buffer with data for transmission. Otherwise, it
305  * returns an error.
306  *
307  * Return:	0 upon success or -1 if the buffer(s) are full.
308  *
309  * Note:	The maximum Tx packet size can not be more than Ethernet header
310  *		(14 Bytes) + Maximum MTU (1500 bytes). This is excluding FCS.
311  */
312 static int xemaclite_send_data(struct net_local *drvdata, u8 *data,
313 			       unsigned int byte_count)
314 {
315 	u32 reg_data;
316 	void __iomem *addr;
317 
318 	/* Determine the expected Tx buffer address */
319 	addr = drvdata->base_addr + drvdata->next_tx_buf_to_use;
320 
321 	/* If the length is too large, truncate it */
322 	if (byte_count > ETH_FRAME_LEN)
323 		byte_count = ETH_FRAME_LEN;
324 
325 	/* Check if the expected buffer is available */
326 	reg_data = __raw_readl(addr + XEL_TSR_OFFSET);
327 	if ((reg_data & (XEL_TSR_XMIT_BUSY_MASK |
328 	     XEL_TSR_XMIT_ACTIVE_MASK)) == 0) {
329 
330 		/* Switch to next buffer if configured */
331 		if (drvdata->tx_ping_pong != 0)
332 			drvdata->next_tx_buf_to_use ^= XEL_BUFFER_OFFSET;
333 	} else if (drvdata->tx_ping_pong != 0) {
334 		/* If the expected buffer is full, try the other buffer,
335 		 * if it is configured in HW */
336 
337 		addr = (void __iomem __force *)((u32 __force)addr ^
338 						 XEL_BUFFER_OFFSET);
339 		reg_data = __raw_readl(addr + XEL_TSR_OFFSET);
340 
341 		if ((reg_data & (XEL_TSR_XMIT_BUSY_MASK |
342 		     XEL_TSR_XMIT_ACTIVE_MASK)) != 0)
343 			return -1; /* Buffers were full, return failure */
344 	} else
345 		return -1; /* Buffer was full, return failure */
346 
347 	/* Write the frame to the buffer */
348 	xemaclite_aligned_write(data, (u32 __force *) addr, byte_count);
349 
350 	__raw_writel((byte_count & XEL_TPLR_LENGTH_MASK),
351 		     addr + XEL_TPLR_OFFSET);
352 
353 	/* Update the Tx Status Register to indicate that there is a
354 	 * frame to send. Set the XEL_TSR_XMIT_ACTIVE_MASK flag which
355 	 * is used by the interrupt handler to check whether a frame
356 	 * has been transmitted */
357 	reg_data = __raw_readl(addr + XEL_TSR_OFFSET);
358 	reg_data |= (XEL_TSR_XMIT_BUSY_MASK | XEL_TSR_XMIT_ACTIVE_MASK);
359 	__raw_writel(reg_data, addr + XEL_TSR_OFFSET);
360 
361 	return 0;
362 }
363 
364 /**
365  * xemaclite_recv_data - Receive a frame
366  * @drvdata:	Pointer to the Emaclite device private data
367  * @data:	Address where the data is to be received
368  *
369  * This function is intended to be called from the interrupt context or
370  * with a wrapper which waits for the receive frame to be available.
371  *
372  * Return:	Total number of bytes received
373  */
374 static u16 xemaclite_recv_data(struct net_local *drvdata, u8 *data)
375 {
376 	void __iomem *addr;
377 	u16 length, proto_type;
378 	u32 reg_data;
379 
380 	/* Determine the expected buffer address */
381 	addr = (drvdata->base_addr + drvdata->next_rx_buf_to_use);
382 
383 	/* Verify which buffer has valid data */
384 	reg_data = __raw_readl(addr + XEL_RSR_OFFSET);
385 
386 	if ((reg_data & XEL_RSR_RECV_DONE_MASK) == XEL_RSR_RECV_DONE_MASK) {
387 		if (drvdata->rx_ping_pong != 0)
388 			drvdata->next_rx_buf_to_use ^= XEL_BUFFER_OFFSET;
389 	} else {
390 		/* The instance is out of sync, try other buffer if other
391 		 * buffer is configured, return 0 otherwise. If the instance is
392 		 * out of sync, do not update the 'next_rx_buf_to_use' since it
393 		 * will correct on subsequent calls */
394 		if (drvdata->rx_ping_pong != 0)
395 			addr = (void __iomem __force *)((u32 __force)addr ^
396 							 XEL_BUFFER_OFFSET);
397 		else
398 			return 0;	/* No data was available */
399 
400 		/* Verify that buffer has valid data */
401 		reg_data = __raw_readl(addr + XEL_RSR_OFFSET);
402 		if ((reg_data & XEL_RSR_RECV_DONE_MASK) !=
403 		     XEL_RSR_RECV_DONE_MASK)
404 			return 0;	/* No data was available */
405 	}
406 
407 	/* Get the protocol type of the ethernet frame that arrived */
408 	proto_type = ((ntohl(__raw_readl(addr + XEL_HEADER_OFFSET +
409 			XEL_RXBUFF_OFFSET)) >> XEL_HEADER_SHIFT) &
410 			XEL_RPLR_LENGTH_MASK);
411 
412 	/* Check if received ethernet frame is a raw ethernet frame
413 	 * or an IP packet or an ARP packet */
414 	if (proto_type > (ETH_FRAME_LEN + ETH_FCS_LEN)) {
415 
416 		if (proto_type == ETH_P_IP) {
417 			length = ((ntohl(__raw_readl(addr +
418 					XEL_HEADER_IP_LENGTH_OFFSET +
419 					XEL_RXBUFF_OFFSET)) >>
420 					XEL_HEADER_SHIFT) &
421 					XEL_RPLR_LENGTH_MASK);
422 			length += ETH_HLEN + ETH_FCS_LEN;
423 
424 		} else if (proto_type == ETH_P_ARP)
425 			length = XEL_ARP_PACKET_SIZE + ETH_HLEN + ETH_FCS_LEN;
426 		else
427 			/* Field contains type other than IP or ARP, use max
428 			 * frame size and let user parse it */
429 			length = ETH_FRAME_LEN + ETH_FCS_LEN;
430 	} else
431 		/* Use the length in the frame, plus the header and trailer */
432 		length = proto_type + ETH_HLEN + ETH_FCS_LEN;
433 
434 	/* Read from the EmacLite device */
435 	xemaclite_aligned_read((u32 __force *) (addr + XEL_RXBUFF_OFFSET),
436 				data, length);
437 
438 	/* Acknowledge the frame */
439 	reg_data = __raw_readl(addr + XEL_RSR_OFFSET);
440 	reg_data &= ~XEL_RSR_RECV_DONE_MASK;
441 	__raw_writel(reg_data, addr + XEL_RSR_OFFSET);
442 
443 	return length;
444 }
445 
446 /**
447  * xemaclite_update_address - Update the MAC address in the device
448  * @drvdata:	Pointer to the Emaclite device private data
449  * @address_ptr:Pointer to the MAC address (MAC address is a 48-bit value)
450  *
451  * Tx must be idle and Rx should be idle for deterministic results.
452  * It is recommended that this function should be called after the
453  * initialization and before transmission of any packets from the device.
454  * The MAC address can be programmed using any of the two transmit
455  * buffers (if configured).
456  */
457 static void xemaclite_update_address(struct net_local *drvdata,
458 				     u8 *address_ptr)
459 {
460 	void __iomem *addr;
461 	u32 reg_data;
462 
463 	/* Determine the expected Tx buffer address */
464 	addr = drvdata->base_addr + drvdata->next_tx_buf_to_use;
465 
466 	xemaclite_aligned_write(address_ptr, (u32 __force *) addr, ETH_ALEN);
467 
468 	__raw_writel(ETH_ALEN, addr + XEL_TPLR_OFFSET);
469 
470 	/* Update the MAC address in the EmacLite */
471 	reg_data = __raw_readl(addr + XEL_TSR_OFFSET);
472 	__raw_writel(reg_data | XEL_TSR_PROG_MAC_ADDR, addr + XEL_TSR_OFFSET);
473 
474 	/* Wait for EmacLite to finish with the MAC address update */
475 	while ((__raw_readl(addr + XEL_TSR_OFFSET) &
476 		XEL_TSR_PROG_MAC_ADDR) != 0)
477 		;
478 }
479 
480 /**
481  * xemaclite_set_mac_address - Set the MAC address for this device
482  * @dev:	Pointer to the network device instance
483  * @addr:	Void pointer to the sockaddr structure
484  *
485  * This function copies the HW address from the sockaddr strucutre to the
486  * net_device structure and updates the address in HW.
487  *
488  * Return:	Error if the net device is busy or 0 if the addr is set
489  *		successfully
490  */
491 static int xemaclite_set_mac_address(struct net_device *dev, void *address)
492 {
493 	struct net_local *lp = netdev_priv(dev);
494 	struct sockaddr *addr = address;
495 
496 	if (netif_running(dev))
497 		return -EBUSY;
498 
499 	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
500 	xemaclite_update_address(lp, dev->dev_addr);
501 	return 0;
502 }
503 
504 /**
505  * xemaclite_tx_timeout - Callback for Tx Timeout
506  * @dev:	Pointer to the network device
507  *
508  * This function is called when Tx time out occurs for Emaclite device.
509  */
510 static void xemaclite_tx_timeout(struct net_device *dev)
511 {
512 	struct net_local *lp = netdev_priv(dev);
513 	unsigned long flags;
514 
515 	dev_err(&lp->ndev->dev, "Exceeded transmit timeout of %lu ms\n",
516 		TX_TIMEOUT * 1000UL / HZ);
517 
518 	dev->stats.tx_errors++;
519 
520 	/* Reset the device */
521 	spin_lock_irqsave(&lp->reset_lock, flags);
522 
523 	/* Shouldn't really be necessary, but shouldn't hurt */
524 	netif_stop_queue(dev);
525 
526 	xemaclite_disable_interrupts(lp);
527 	xemaclite_enable_interrupts(lp);
528 
529 	if (lp->deferred_skb) {
530 		dev_kfree_skb(lp->deferred_skb);
531 		lp->deferred_skb = NULL;
532 		dev->stats.tx_errors++;
533 	}
534 
535 	/* To exclude tx timeout */
536 	dev->trans_start = jiffies; /* prevent tx timeout */
537 
538 	/* We're all ready to go. Start the queue */
539 	netif_wake_queue(dev);
540 	spin_unlock_irqrestore(&lp->reset_lock, flags);
541 }
542 
543 /**********************/
544 /* Interrupt Handlers */
545 /**********************/
546 
547 /**
548  * xemaclite_tx_handler - Interrupt handler for frames sent
549  * @dev:	Pointer to the network device
550  *
551  * This function updates the number of packets transmitted and handles the
552  * deferred skb, if there is one.
553  */
554 static void xemaclite_tx_handler(struct net_device *dev)
555 {
556 	struct net_local *lp = netdev_priv(dev);
557 
558 	dev->stats.tx_packets++;
559 	if (lp->deferred_skb) {
560 		if (xemaclite_send_data(lp,
561 					(u8 *) lp->deferred_skb->data,
562 					lp->deferred_skb->len) != 0)
563 			return;
564 		else {
565 			dev->stats.tx_bytes += lp->deferred_skb->len;
566 			dev_kfree_skb_irq(lp->deferred_skb);
567 			lp->deferred_skb = NULL;
568 			dev->trans_start = jiffies; /* prevent tx timeout */
569 			netif_wake_queue(dev);
570 		}
571 	}
572 }
573 
574 /**
575  * xemaclite_rx_handler- Interrupt handler for frames received
576  * @dev:	Pointer to the network device
577  *
578  * This function allocates memory for a socket buffer, fills it with data
579  * received and hands it over to the TCP/IP stack.
580  */
581 static void xemaclite_rx_handler(struct net_device *dev)
582 {
583 	struct net_local *lp = netdev_priv(dev);
584 	struct sk_buff *skb;
585 	unsigned int align;
586 	u32 len;
587 
588 	len = ETH_FRAME_LEN + ETH_FCS_LEN;
589 	skb = netdev_alloc_skb(dev, len + ALIGNMENT);
590 	if (!skb) {
591 		/* Couldn't get memory. */
592 		dev->stats.rx_dropped++;
593 		dev_err(&lp->ndev->dev, "Could not allocate receive buffer\n");
594 		return;
595 	}
596 
597 	/*
598 	 * A new skb should have the data halfword aligned, but this code is
599 	 * here just in case that isn't true. Calculate how many
600 	 * bytes we should reserve to get the data to start on a word
601 	 * boundary */
602 	align = BUFFER_ALIGN(skb->data);
603 	if (align)
604 		skb_reserve(skb, align);
605 
606 	skb_reserve(skb, 2);
607 
608 	len = xemaclite_recv_data(lp, (u8 *) skb->data);
609 
610 	if (!len) {
611 		dev->stats.rx_errors++;
612 		dev_kfree_skb_irq(skb);
613 		return;
614 	}
615 
616 	skb_put(skb, len);	/* Tell the skb how much data we got */
617 
618 	skb->protocol = eth_type_trans(skb, dev);
619 	skb_checksum_none_assert(skb);
620 
621 	dev->stats.rx_packets++;
622 	dev->stats.rx_bytes += len;
623 
624 	if (!skb_defer_rx_timestamp(skb))
625 		netif_rx(skb);	/* Send the packet upstream */
626 }
627 
628 /**
629  * xemaclite_interrupt - Interrupt handler for this driver
630  * @irq:	Irq of the Emaclite device
631  * @dev_id:	Void pointer to the network device instance used as callback
632  *		reference
633  *
634  * This function handles the Tx and Rx interrupts of the EmacLite device.
635  */
636 static irqreturn_t xemaclite_interrupt(int irq, void *dev_id)
637 {
638 	bool tx_complete = false;
639 	struct net_device *dev = dev_id;
640 	struct net_local *lp = netdev_priv(dev);
641 	void __iomem *base_addr = lp->base_addr;
642 	u32 tx_status;
643 
644 	/* Check if there is Rx Data available */
645 	if ((__raw_readl(base_addr + XEL_RSR_OFFSET) &
646 			 XEL_RSR_RECV_DONE_MASK) ||
647 	    (__raw_readl(base_addr + XEL_BUFFER_OFFSET + XEL_RSR_OFFSET)
648 			 & XEL_RSR_RECV_DONE_MASK))
649 
650 		xemaclite_rx_handler(dev);
651 
652 	/* Check if the Transmission for the first buffer is completed */
653 	tx_status = __raw_readl(base_addr + XEL_TSR_OFFSET);
654 	if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
655 		(tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {
656 
657 		tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
658 		__raw_writel(tx_status, base_addr + XEL_TSR_OFFSET);
659 
660 		tx_complete = true;
661 	}
662 
663 	/* Check if the Transmission for the second buffer is completed */
664 	tx_status = __raw_readl(base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);
665 	if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
666 		(tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {
667 
668 		tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
669 		__raw_writel(tx_status, base_addr + XEL_BUFFER_OFFSET +
670 			     XEL_TSR_OFFSET);
671 
672 		tx_complete = true;
673 	}
674 
675 	/* If there was a Tx interrupt, call the Tx Handler */
676 	if (tx_complete != 0)
677 		xemaclite_tx_handler(dev);
678 
679 	return IRQ_HANDLED;
680 }
681 
682 /**********************/
683 /* MDIO Bus functions */
684 /**********************/
685 
686 /**
687  * xemaclite_mdio_wait - Wait for the MDIO to be ready to use
688  * @lp:		Pointer to the Emaclite device private data
689  *
690  * This function waits till the device is ready to accept a new MDIO
691  * request.
692  *
693  * Return:	0 for success or ETIMEDOUT for a timeout
694  */
695 
696 static int xemaclite_mdio_wait(struct net_local *lp)
697 {
698 	unsigned long end = jiffies + 2;
699 
700 	/* wait for the MDIO interface to not be busy or timeout
701 	   after some time.
702 	*/
703 	while (__raw_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET) &
704 			XEL_MDIOCTRL_MDIOSTS_MASK) {
705 		if (time_before_eq(end, jiffies)) {
706 			WARN_ON(1);
707 			return -ETIMEDOUT;
708 		}
709 		msleep(1);
710 	}
711 	return 0;
712 }
713 
714 /**
715  * xemaclite_mdio_read - Read from a given MII management register
716  * @bus:	the mii_bus struct
717  * @phy_id:	the phy address
718  * @reg:	register number to read from
719  *
720  * This function waits till the device is ready to accept a new MDIO
721  * request and then writes the phy address to the MDIO Address register
722  * and reads data from MDIO Read Data register, when its available.
723  *
724  * Return:	Value read from the MII management register
725  */
726 static int xemaclite_mdio_read(struct mii_bus *bus, int phy_id, int reg)
727 {
728 	struct net_local *lp = bus->priv;
729 	u32 ctrl_reg;
730 	u32 rc;
731 
732 	if (xemaclite_mdio_wait(lp))
733 		return -ETIMEDOUT;
734 
735 	/* Write the PHY address, register number and set the OP bit in the
736 	 * MDIO Address register. Set the Status bit in the MDIO Control
737 	 * register to start a MDIO read transaction.
738 	 */
739 	ctrl_reg = __raw_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
740 	__raw_writel(XEL_MDIOADDR_OP_MASK |
741 		     ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
742 		     lp->base_addr + XEL_MDIOADDR_OFFSET);
743 	__raw_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
744 		     lp->base_addr + XEL_MDIOCTRL_OFFSET);
745 
746 	if (xemaclite_mdio_wait(lp))
747 		return -ETIMEDOUT;
748 
749 	rc = __raw_readl(lp->base_addr + XEL_MDIORD_OFFSET);
750 
751 	dev_dbg(&lp->ndev->dev,
752 		"xemaclite_mdio_read(phy_id=%i, reg=%x) == %x\n",
753 		phy_id, reg, rc);
754 
755 	return rc;
756 }
757 
758 /**
759  * xemaclite_mdio_write - Write to a given MII management register
760  * @bus:	the mii_bus struct
761  * @phy_id:	the phy address
762  * @reg:	register number to write to
763  * @val:	value to write to the register number specified by reg
764  *
765  * This function waits till the device is ready to accept a new MDIO
766  * request and then writes the val to the MDIO Write Data register.
767  */
768 static int xemaclite_mdio_write(struct mii_bus *bus, int phy_id, int reg,
769 				u16 val)
770 {
771 	struct net_local *lp = bus->priv;
772 	u32 ctrl_reg;
773 
774 	dev_dbg(&lp->ndev->dev,
775 		"xemaclite_mdio_write(phy_id=%i, reg=%x, val=%x)\n",
776 		phy_id, reg, val);
777 
778 	if (xemaclite_mdio_wait(lp))
779 		return -ETIMEDOUT;
780 
781 	/* Write the PHY address, register number and clear the OP bit in the
782 	 * MDIO Address register and then write the value into the MDIO Write
783 	 * Data register. Finally, set the Status bit in the MDIO Control
784 	 * register to start a MDIO write transaction.
785 	 */
786 	ctrl_reg = __raw_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
787 	__raw_writel(~XEL_MDIOADDR_OP_MASK &
788 		     ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
789 		     lp->base_addr + XEL_MDIOADDR_OFFSET);
790 	__raw_writel(val, lp->base_addr + XEL_MDIOWR_OFFSET);
791 	__raw_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
792 		     lp->base_addr + XEL_MDIOCTRL_OFFSET);
793 
794 	return 0;
795 }
796 
797 /**
798  * xemaclite_mdio_setup - Register mii_bus for the Emaclite device
799  * @lp:		Pointer to the Emaclite device private data
800  * @ofdev:	Pointer to OF device structure
801  *
802  * This function enables MDIO bus in the Emaclite device and registers a
803  * mii_bus.
804  *
805  * Return:	0 upon success or a negative error upon failure
806  */
807 static int xemaclite_mdio_setup(struct net_local *lp, struct device *dev)
808 {
809 	struct mii_bus *bus;
810 	int rc;
811 	struct resource res;
812 	struct device_node *np = of_get_parent(lp->phy_node);
813 	struct device_node *npp;
814 
815 	/* Don't register the MDIO bus if the phy_node or its parent node
816 	 * can't be found.
817 	 */
818 	if (!np) {
819 		dev_err(dev, "Failed to register mdio bus.\n");
820 		return -ENODEV;
821 	}
822 	npp = of_get_parent(np);
823 
824 	of_address_to_resource(npp, 0, &res);
825 	if (lp->ndev->mem_start != res.start) {
826 		struct phy_device *phydev;
827 		phydev = of_phy_find_device(lp->phy_node);
828 		if (!phydev)
829 			dev_info(dev,
830 				 "MDIO of the phy is not registered yet\n");
831 		return 0;
832 	}
833 
834 	/* Enable the MDIO bus by asserting the enable bit in MDIO Control
835 	 * register.
836 	 */
837 	__raw_writel(XEL_MDIOCTRL_MDIOEN_MASK,
838 		     lp->base_addr + XEL_MDIOCTRL_OFFSET);
839 
840 	bus = mdiobus_alloc();
841 	if (!bus) {
842 		dev_err(dev, "Failed to allocate mdiobus\n");
843 		return -ENOMEM;
844 	}
845 
846 	snprintf(bus->id, MII_BUS_ID_SIZE, "%.8llx",
847 		 (unsigned long long)res.start);
848 	bus->priv = lp;
849 	bus->name = "Xilinx Emaclite MDIO";
850 	bus->read = xemaclite_mdio_read;
851 	bus->write = xemaclite_mdio_write;
852 	bus->parent = dev;
853 	bus->irq = lp->mdio_irqs; /* preallocated IRQ table */
854 
855 	lp->mii_bus = bus;
856 
857 	rc = of_mdiobus_register(bus, np);
858 	if (rc) {
859 		dev_err(dev, "Failed to register mdio bus.\n");
860 		goto err_register;
861 	}
862 
863 	return 0;
864 
865 err_register:
866 	mdiobus_free(bus);
867 	return rc;
868 }
869 
870 /**
871  * xemaclite_adjust_link - Link state callback for the Emaclite device
872  * @ndev: pointer to net_device struct
873  *
874  * There's nothing in the Emaclite device to be configured when the link
875  * state changes. We just print the status.
876  */
877 static void xemaclite_adjust_link(struct net_device *ndev)
878 {
879 	struct net_local *lp = netdev_priv(ndev);
880 	struct phy_device *phy = lp->phy_dev;
881 	int link_state;
882 
883 	/* hash together the state values to decide if something has changed */
884 	link_state = phy->speed | (phy->duplex << 1) | phy->link;
885 
886 	if (lp->last_link != link_state) {
887 		lp->last_link = link_state;
888 		phy_print_status(phy);
889 	}
890 }
891 
892 /**
893  * xemaclite_open - Open the network device
894  * @dev:	Pointer to the network device
895  *
896  * This function sets the MAC address, requests an IRQ and enables interrupts
897  * for the Emaclite device and starts the Tx queue.
898  * It also connects to the phy device, if MDIO is included in Emaclite device.
899  */
900 static int xemaclite_open(struct net_device *dev)
901 {
902 	struct net_local *lp = netdev_priv(dev);
903 	int retval;
904 
905 	/* Just to be safe, stop the device first */
906 	xemaclite_disable_interrupts(lp);
907 
908 	if (lp->phy_node) {
909 		u32 bmcr;
910 
911 		lp->phy_dev = of_phy_connect(lp->ndev, lp->phy_node,
912 					     xemaclite_adjust_link, 0,
913 					     PHY_INTERFACE_MODE_MII);
914 		if (!lp->phy_dev) {
915 			dev_err(&lp->ndev->dev, "of_phy_connect() failed\n");
916 			return -ENODEV;
917 		}
918 
919 		/* EmacLite doesn't support giga-bit speeds */
920 		lp->phy_dev->supported &= (PHY_BASIC_FEATURES);
921 		lp->phy_dev->advertising = lp->phy_dev->supported;
922 
923 		/* Don't advertise 1000BASE-T Full/Half duplex speeds */
924 		phy_write(lp->phy_dev, MII_CTRL1000, 0);
925 
926 		/* Advertise only 10 and 100mbps full/half duplex speeds */
927 		phy_write(lp->phy_dev, MII_ADVERTISE, ADVERTISE_ALL |
928 			  ADVERTISE_CSMA);
929 
930 		/* Restart auto negotiation */
931 		bmcr = phy_read(lp->phy_dev, MII_BMCR);
932 		bmcr |= (BMCR_ANENABLE | BMCR_ANRESTART);
933 		phy_write(lp->phy_dev, MII_BMCR, bmcr);
934 
935 		phy_start(lp->phy_dev);
936 	}
937 
938 	/* Set the MAC address each time opened */
939 	xemaclite_update_address(lp, dev->dev_addr);
940 
941 	/* Grab the IRQ */
942 	retval = request_irq(dev->irq, xemaclite_interrupt, 0, dev->name, dev);
943 	if (retval) {
944 		dev_err(&lp->ndev->dev, "Could not allocate interrupt %d\n",
945 			dev->irq);
946 		if (lp->phy_dev)
947 			phy_disconnect(lp->phy_dev);
948 		lp->phy_dev = NULL;
949 
950 		return retval;
951 	}
952 
953 	/* Enable Interrupts */
954 	xemaclite_enable_interrupts(lp);
955 
956 	/* We're ready to go */
957 	netif_start_queue(dev);
958 
959 	return 0;
960 }
961 
962 /**
963  * xemaclite_close - Close the network device
964  * @dev:	Pointer to the network device
965  *
966  * This function stops the Tx queue, disables interrupts and frees the IRQ for
967  * the Emaclite device.
968  * It also disconnects the phy device associated with the Emaclite device.
969  */
970 static int xemaclite_close(struct net_device *dev)
971 {
972 	struct net_local *lp = netdev_priv(dev);
973 
974 	netif_stop_queue(dev);
975 	xemaclite_disable_interrupts(lp);
976 	free_irq(dev->irq, dev);
977 
978 	if (lp->phy_dev)
979 		phy_disconnect(lp->phy_dev);
980 	lp->phy_dev = NULL;
981 
982 	return 0;
983 }
984 
985 /**
986  * xemaclite_send - Transmit a frame
987  * @orig_skb:	Pointer to the socket buffer to be transmitted
988  * @dev:	Pointer to the network device
989  *
990  * This function checks if the Tx buffer of the Emaclite device is free to send
991  * data. If so, it fills the Tx buffer with data from socket buffer data,
992  * updates the stats and frees the socket buffer. The Tx completion is signaled
993  * by an interrupt. If the Tx buffer isn't free, then the socket buffer is
994  * deferred and the Tx queue is stopped so that the deferred socket buffer can
995  * be transmitted when the Emaclite device is free to transmit data.
996  *
997  * Return:	0, always.
998  */
999 static int xemaclite_send(struct sk_buff *orig_skb, struct net_device *dev)
1000 {
1001 	struct net_local *lp = netdev_priv(dev);
1002 	struct sk_buff *new_skb;
1003 	unsigned int len;
1004 	unsigned long flags;
1005 
1006 	len = orig_skb->len;
1007 
1008 	new_skb = orig_skb;
1009 
1010 	spin_lock_irqsave(&lp->reset_lock, flags);
1011 	if (xemaclite_send_data(lp, (u8 *) new_skb->data, len) != 0) {
1012 		/* If the Emaclite Tx buffer is busy, stop the Tx queue and
1013 		 * defer the skb for transmission during the ISR, after the
1014 		 * current transmission is complete */
1015 		netif_stop_queue(dev);
1016 		lp->deferred_skb = new_skb;
1017 		/* Take the time stamp now, since we can't do this in an ISR. */
1018 		skb_tx_timestamp(new_skb);
1019 		spin_unlock_irqrestore(&lp->reset_lock, flags);
1020 		return 0;
1021 	}
1022 	spin_unlock_irqrestore(&lp->reset_lock, flags);
1023 
1024 	skb_tx_timestamp(new_skb);
1025 
1026 	dev->stats.tx_bytes += len;
1027 	dev_consume_skb_any(new_skb);
1028 
1029 	return 0;
1030 }
1031 
1032 /**
1033  * xemaclite_remove_ndev - Free the network device
1034  * @ndev:	Pointer to the network device to be freed
1035  *
1036  * This function un maps the IO region of the Emaclite device and frees the net
1037  * device.
1038  */
1039 static void xemaclite_remove_ndev(struct net_device *ndev)
1040 {
1041 	if (ndev) {
1042 		free_netdev(ndev);
1043 	}
1044 }
1045 
1046 /**
1047  * get_bool - Get a parameter from the OF device
1048  * @ofdev:	Pointer to OF device structure
1049  * @s:		Property to be retrieved
1050  *
1051  * This function looks for a property in the device node and returns the value
1052  * of the property if its found or 0 if the property is not found.
1053  *
1054  * Return:	Value of the parameter if the parameter is found, or 0 otherwise
1055  */
1056 static bool get_bool(struct platform_device *ofdev, const char *s)
1057 {
1058 	u32 *p = (u32 *)of_get_property(ofdev->dev.of_node, s, NULL);
1059 
1060 	if (p) {
1061 		return (bool)*p;
1062 	} else {
1063 		dev_warn(&ofdev->dev, "Parameter %s not found,"
1064 			"defaulting to false\n", s);
1065 		return false;
1066 	}
1067 }
1068 
1069 static struct net_device_ops xemaclite_netdev_ops;
1070 
1071 /**
1072  * xemaclite_of_probe - Probe method for the Emaclite device.
1073  * @ofdev:	Pointer to OF device structure
1074  * @match:	Pointer to the structure used for matching a device
1075  *
1076  * This function probes for the Emaclite device in the device tree.
1077  * It initializes the driver data structure and the hardware, sets the MAC
1078  * address and registers the network device.
1079  * It also registers a mii_bus for the Emaclite device, if MDIO is included
1080  * in the device.
1081  *
1082  * Return:	0, if the driver is bound to the Emaclite device, or
1083  *		a negative error if there is failure.
1084  */
1085 static int xemaclite_of_probe(struct platform_device *ofdev)
1086 {
1087 	struct resource *res;
1088 	struct net_device *ndev = NULL;
1089 	struct net_local *lp = NULL;
1090 	struct device *dev = &ofdev->dev;
1091 	const void *mac_address;
1092 
1093 	int rc = 0;
1094 
1095 	dev_info(dev, "Device Tree Probing\n");
1096 
1097 	/* Create an ethernet device instance */
1098 	ndev = alloc_etherdev(sizeof(struct net_local));
1099 	if (!ndev)
1100 		return -ENOMEM;
1101 
1102 	dev_set_drvdata(dev, ndev);
1103 	SET_NETDEV_DEV(ndev, &ofdev->dev);
1104 
1105 	lp = netdev_priv(ndev);
1106 	lp->ndev = ndev;
1107 
1108 	/* Get IRQ for the device */
1109 	res = platform_get_resource(ofdev, IORESOURCE_IRQ, 0);
1110 	if (!res) {
1111 		dev_err(dev, "no IRQ found\n");
1112 		rc = -ENXIO;
1113 		goto error;
1114 	}
1115 
1116 	ndev->irq = res->start;
1117 
1118 	res = platform_get_resource(ofdev, IORESOURCE_MEM, 0);
1119 	lp->base_addr = devm_ioremap_resource(&ofdev->dev, res);
1120 	if (IS_ERR(lp->base_addr)) {
1121 		rc = PTR_ERR(lp->base_addr);
1122 		goto error;
1123 	}
1124 
1125 	ndev->mem_start = res->start;
1126 	ndev->mem_end = res->end;
1127 
1128 	spin_lock_init(&lp->reset_lock);
1129 	lp->next_tx_buf_to_use = 0x0;
1130 	lp->next_rx_buf_to_use = 0x0;
1131 	lp->tx_ping_pong = get_bool(ofdev, "xlnx,tx-ping-pong");
1132 	lp->rx_ping_pong = get_bool(ofdev, "xlnx,rx-ping-pong");
1133 	mac_address = of_get_mac_address(ofdev->dev.of_node);
1134 
1135 	if (mac_address)
1136 		/* Set the MAC address. */
1137 		memcpy(ndev->dev_addr, mac_address, ETH_ALEN);
1138 	else
1139 		dev_warn(dev, "No MAC address found\n");
1140 
1141 	/* Clear the Tx CSR's in case this is a restart */
1142 	__raw_writel(0, lp->base_addr + XEL_TSR_OFFSET);
1143 	__raw_writel(0, lp->base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);
1144 
1145 	/* Set the MAC address in the EmacLite device */
1146 	xemaclite_update_address(lp, ndev->dev_addr);
1147 
1148 	lp->phy_node = of_parse_phandle(ofdev->dev.of_node, "phy-handle", 0);
1149 	rc = xemaclite_mdio_setup(lp, &ofdev->dev);
1150 	if (rc)
1151 		dev_warn(&ofdev->dev, "error registering MDIO bus\n");
1152 
1153 	dev_info(dev, "MAC address is now %pM\n", ndev->dev_addr);
1154 
1155 	ndev->netdev_ops = &xemaclite_netdev_ops;
1156 	ndev->flags &= ~IFF_MULTICAST;
1157 	ndev->watchdog_timeo = TX_TIMEOUT;
1158 
1159 	/* Finally, register the device */
1160 	rc = register_netdev(ndev);
1161 	if (rc) {
1162 		dev_err(dev,
1163 			"Cannot register network device, aborting\n");
1164 		goto error;
1165 	}
1166 
1167 	dev_info(dev,
1168 		 "Xilinx EmacLite at 0x%08X mapped to 0x%08X, irq=%d\n",
1169 		 (unsigned int __force)ndev->mem_start,
1170 		 (unsigned int __force)lp->base_addr, ndev->irq);
1171 	return 0;
1172 
1173 error:
1174 	xemaclite_remove_ndev(ndev);
1175 	return rc;
1176 }
1177 
1178 /**
1179  * xemaclite_of_remove - Unbind the driver from the Emaclite device.
1180  * @of_dev:	Pointer to OF device structure
1181  *
1182  * This function is called if a device is physically removed from the system or
1183  * if the driver module is being unloaded. It frees any resources allocated to
1184  * the device.
1185  *
1186  * Return:	0, always.
1187  */
1188 static int xemaclite_of_remove(struct platform_device *of_dev)
1189 {
1190 	struct net_device *ndev = platform_get_drvdata(of_dev);
1191 
1192 	struct net_local *lp = netdev_priv(ndev);
1193 
1194 	/* Un-register the mii_bus, if configured */
1195 	if (lp->has_mdio) {
1196 		mdiobus_unregister(lp->mii_bus);
1197 		kfree(lp->mii_bus->irq);
1198 		mdiobus_free(lp->mii_bus);
1199 		lp->mii_bus = NULL;
1200 	}
1201 
1202 	unregister_netdev(ndev);
1203 
1204 	of_node_put(lp->phy_node);
1205 	lp->phy_node = NULL;
1206 
1207 	xemaclite_remove_ndev(ndev);
1208 
1209 	return 0;
1210 }
1211 
1212 #ifdef CONFIG_NET_POLL_CONTROLLER
1213 static void
1214 xemaclite_poll_controller(struct net_device *ndev)
1215 {
1216 	disable_irq(ndev->irq);
1217 	xemaclite_interrupt(ndev->irq, ndev);
1218 	enable_irq(ndev->irq);
1219 }
1220 #endif
1221 
1222 static struct net_device_ops xemaclite_netdev_ops = {
1223 	.ndo_open		= xemaclite_open,
1224 	.ndo_stop		= xemaclite_close,
1225 	.ndo_start_xmit		= xemaclite_send,
1226 	.ndo_set_mac_address	= xemaclite_set_mac_address,
1227 	.ndo_tx_timeout		= xemaclite_tx_timeout,
1228 #ifdef CONFIG_NET_POLL_CONTROLLER
1229 	.ndo_poll_controller = xemaclite_poll_controller,
1230 #endif
1231 };
1232 
1233 /* Match table for OF platform binding */
1234 static const struct of_device_id xemaclite_of_match[] = {
1235 	{ .compatible = "xlnx,opb-ethernetlite-1.01.a", },
1236 	{ .compatible = "xlnx,opb-ethernetlite-1.01.b", },
1237 	{ .compatible = "xlnx,xps-ethernetlite-1.00.a", },
1238 	{ .compatible = "xlnx,xps-ethernetlite-2.00.a", },
1239 	{ .compatible = "xlnx,xps-ethernetlite-2.01.a", },
1240 	{ .compatible = "xlnx,xps-ethernetlite-3.00.a", },
1241 	{ /* end of list */ },
1242 };
1243 MODULE_DEVICE_TABLE(of, xemaclite_of_match);
1244 
1245 static struct platform_driver xemaclite_of_driver = {
1246 	.driver = {
1247 		.name = DRIVER_NAME,
1248 		.of_match_table = xemaclite_of_match,
1249 	},
1250 	.probe		= xemaclite_of_probe,
1251 	.remove		= xemaclite_of_remove,
1252 };
1253 
1254 module_platform_driver(xemaclite_of_driver);
1255 
1256 MODULE_AUTHOR("Xilinx, Inc.");
1257 MODULE_DESCRIPTION("Xilinx Ethernet MAC Lite driver");
1258 MODULE_LICENSE("GPL");
1259