xref: /linux/drivers/net/ethernet/xilinx/xilinx_emaclite.c (revision fcc79e1714e8c2b8e216dc3149812edd37884eef)
1 // SPDX-License-Identifier: GPL-2.0-or-later
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  * Copyright (c) 2007 - 2013 Xilinx, Inc.
8  */
9 
10 #include <linux/clk.h>
11 #include <linux/module.h>
12 #include <linux/platform_device.h>
13 #include <linux/uaccess.h>
14 #include <linux/netdevice.h>
15 #include <linux/etherdevice.h>
16 #include <linux/skbuff.h>
17 #include <linux/ethtool.h>
18 #include <linux/io.h>
19 #include <linux/slab.h>
20 #include <linux/of.h>
21 #include <linux/of_address.h>
22 #include <linux/of_mdio.h>
23 #include <linux/of_net.h>
24 #include <linux/phy.h>
25 #include <linux/interrupt.h>
26 #include <linux/iopoll.h>
27 
28 #define DRIVER_NAME "xilinx_emaclite"
29 
30 /* Register offsets for the EmacLite Core */
31 #define XEL_TXBUFF_OFFSET	0x0		/* Transmit Buffer */
32 #define XEL_MDIOADDR_OFFSET	0x07E4		/* MDIO Address Register */
33 #define XEL_MDIOWR_OFFSET	0x07E8		/* MDIO Write Data Register */
34 #define XEL_MDIORD_OFFSET	0x07EC		/* MDIO Read Data Register */
35 #define XEL_MDIOCTRL_OFFSET	0x07F0		/* MDIO Control Register */
36 #define XEL_GIER_OFFSET		0x07F8		/* GIE Register */
37 #define XEL_TSR_OFFSET		0x07FC		/* Tx status */
38 #define XEL_TPLR_OFFSET		0x07F4		/* Tx packet length */
39 
40 #define XEL_RXBUFF_OFFSET	0x1000		/* Receive Buffer */
41 #define XEL_RPLR_OFFSET		0x100C		/* Rx packet length */
42 #define XEL_RSR_OFFSET		0x17FC		/* Rx status */
43 
44 #define XEL_BUFFER_OFFSET	0x0800		/* Next Tx/Rx buffer's offset */
45 
46 /* MDIO Address Register Bit Masks */
47 #define XEL_MDIOADDR_REGADR_MASK  0x0000001F	/* Register Address */
48 #define XEL_MDIOADDR_PHYADR_MASK  0x000003E0	/* PHY Address */
49 #define XEL_MDIOADDR_PHYADR_SHIFT 5
50 #define XEL_MDIOADDR_OP_MASK	  0x00000400	/* RD/WR Operation */
51 
52 /* MDIO Write Data Register Bit Masks */
53 #define XEL_MDIOWR_WRDATA_MASK	  0x0000FFFF	/* Data to be Written */
54 
55 /* MDIO Read Data Register Bit Masks */
56 #define XEL_MDIORD_RDDATA_MASK	  0x0000FFFF	/* Data to be Read */
57 
58 /* MDIO Control Register Bit Masks */
59 #define XEL_MDIOCTRL_MDIOSTS_MASK 0x00000001	/* MDIO Status Mask */
60 #define XEL_MDIOCTRL_MDIOEN_MASK  0x00000008	/* MDIO Enable */
61 
62 /* Global Interrupt Enable Register (GIER) Bit Masks */
63 #define XEL_GIER_GIE_MASK	0x80000000	/* Global Enable */
64 
65 /* Transmit Status Register (TSR) Bit Masks */
66 #define XEL_TSR_XMIT_BUSY_MASK	 0x00000001	/* Tx complete */
67 #define XEL_TSR_PROGRAM_MASK	 0x00000002	/* Program the MAC address */
68 #define XEL_TSR_XMIT_IE_MASK	 0x00000008	/* Tx interrupt enable bit */
69 #define XEL_TSR_XMIT_ACTIVE_MASK 0x80000000	/* Buffer is active, SW bit
70 						 * only. This is not documented
71 						 * in the HW spec
72 						 */
73 
74 /* Define for programming the MAC address into the EmacLite */
75 #define XEL_TSR_PROG_MAC_ADDR	(XEL_TSR_XMIT_BUSY_MASK | XEL_TSR_PROGRAM_MASK)
76 
77 /* Receive Status Register (RSR) */
78 #define XEL_RSR_RECV_DONE_MASK	0x00000001	/* Rx complete */
79 #define XEL_RSR_RECV_IE_MASK	0x00000008	/* Rx interrupt enable bit */
80 
81 /* Transmit Packet Length Register (TPLR) */
82 #define XEL_TPLR_LENGTH_MASK	0x0000FFFF	/* Tx packet length */
83 
84 /* Receive Packet Length Register (RPLR) */
85 #define XEL_RPLR_LENGTH_MASK	0x0000FFFF	/* Rx packet length */
86 
87 #define XEL_HEADER_OFFSET	12		/* Offset to length field */
88 #define XEL_HEADER_SHIFT	16		/* Shift value for length */
89 
90 /* General Ethernet Definitions */
91 #define XEL_ARP_PACKET_SIZE		28	/* Max ARP packet size */
92 #define XEL_HEADER_IP_LENGTH_OFFSET	16	/* IP Length Offset */
93 
94 #define TX_TIMEOUT		(60 * HZ)	/* Tx timeout is 60 seconds. */
95 
96 #ifdef __BIG_ENDIAN
97 #define xemaclite_readl		ioread32be
98 #define xemaclite_writel	iowrite32be
99 #else
100 #define xemaclite_readl		ioread32
101 #define xemaclite_writel	iowrite32
102 #endif
103 
104 /**
105  * struct net_local - Our private per device data
106  * @ndev:		instance of the network device
107  * @tx_ping_pong:	indicates whether Tx Pong buffer is configured in HW
108  * @rx_ping_pong:	indicates whether Rx Pong buffer is configured in HW
109  * @next_tx_buf_to_use:	next Tx buffer to write to
110  * @next_rx_buf_to_use:	next Rx buffer to read from
111  * @base_addr:		base address of the Emaclite device
112  * @reset_lock:		lock to serialize xmit and tx_timeout execution
113  * @deferred_skb:	holds an skb (for transmission at a later time) when the
114  *			Tx buffer is not free
115  * @phy_dev:		pointer to the PHY device
116  * @phy_node:		pointer to the PHY device node
117  * @mii_bus:		pointer to the MII bus
118  * @last_link:		last link status
119  */
120 struct net_local {
121 	struct net_device *ndev;
122 
123 	bool tx_ping_pong;
124 	bool rx_ping_pong;
125 	u32 next_tx_buf_to_use;
126 	u32 next_rx_buf_to_use;
127 	void __iomem *base_addr;
128 
129 	spinlock_t reset_lock; /* serialize xmit and tx_timeout execution */
130 	struct sk_buff *deferred_skb;
131 
132 	struct phy_device *phy_dev;
133 	struct device_node *phy_node;
134 
135 	struct mii_bus *mii_bus;
136 
137 	int last_link;
138 };
139 
140 /*************************/
141 /* EmacLite driver calls */
142 /*************************/
143 
144 /**
145  * xemaclite_enable_interrupts - Enable the interrupts for the EmacLite device
146  * @drvdata:	Pointer to the Emaclite device private data
147  *
148  * This function enables the Tx and Rx interrupts for the Emaclite device along
149  * with the Global Interrupt Enable.
150  */
151 static void xemaclite_enable_interrupts(struct net_local *drvdata)
152 {
153 	u32 reg_data;
154 
155 	/* Enable the Tx interrupts for the first Buffer */
156 	reg_data = xemaclite_readl(drvdata->base_addr + XEL_TSR_OFFSET);
157 	xemaclite_writel(reg_data | XEL_TSR_XMIT_IE_MASK,
158 			 drvdata->base_addr + XEL_TSR_OFFSET);
159 
160 	/* Enable the Rx interrupts for the first buffer */
161 	xemaclite_writel(XEL_RSR_RECV_IE_MASK, drvdata->base_addr + XEL_RSR_OFFSET);
162 
163 	/* Enable the Global Interrupt Enable */
164 	xemaclite_writel(XEL_GIER_GIE_MASK, drvdata->base_addr + XEL_GIER_OFFSET);
165 }
166 
167 /**
168  * xemaclite_disable_interrupts - Disable the interrupts for the EmacLite device
169  * @drvdata:	Pointer to the Emaclite device private data
170  *
171  * This function disables the Tx and Rx interrupts for the Emaclite device,
172  * along with the Global Interrupt Enable.
173  */
174 static void xemaclite_disable_interrupts(struct net_local *drvdata)
175 {
176 	u32 reg_data;
177 
178 	/* Disable the Global Interrupt Enable */
179 	xemaclite_writel(XEL_GIER_GIE_MASK, drvdata->base_addr + XEL_GIER_OFFSET);
180 
181 	/* Disable the Tx interrupts for the first buffer */
182 	reg_data = xemaclite_readl(drvdata->base_addr + XEL_TSR_OFFSET);
183 	xemaclite_writel(reg_data & (~XEL_TSR_XMIT_IE_MASK),
184 			 drvdata->base_addr + XEL_TSR_OFFSET);
185 
186 	/* Disable the Rx interrupts for the first buffer */
187 	reg_data = xemaclite_readl(drvdata->base_addr + XEL_RSR_OFFSET);
188 	xemaclite_writel(reg_data & (~XEL_RSR_RECV_IE_MASK),
189 			 drvdata->base_addr + XEL_RSR_OFFSET);
190 }
191 
192 /**
193  * xemaclite_aligned_write - Write from 16-bit aligned to 32-bit aligned address
194  * @src_ptr:	Void pointer to the 16-bit aligned source address
195  * @dest_ptr:	Pointer to the 32-bit aligned destination address
196  * @length:	Number bytes to write from source to destination
197  *
198  * This function writes data from a 16-bit aligned buffer to a 32-bit aligned
199  * address in the EmacLite device.
200  */
201 static void xemaclite_aligned_write(const void *src_ptr, u32 *dest_ptr,
202 				    unsigned int length)
203 {
204 	const u16 *from_u16_ptr;
205 	u32 align_buffer;
206 	u32 *to_u32_ptr;
207 	u16 *to_u16_ptr;
208 
209 	to_u32_ptr = dest_ptr;
210 	from_u16_ptr = src_ptr;
211 	align_buffer = 0;
212 
213 	for (; length > 3; length -= 4) {
214 		to_u16_ptr = (u16 *)&align_buffer;
215 		*to_u16_ptr++ = *from_u16_ptr++;
216 		*to_u16_ptr++ = *from_u16_ptr++;
217 
218 		/* This barrier resolves occasional issues seen around
219 		 * cases where the data is not properly flushed out
220 		 * from the processor store buffers to the destination
221 		 * memory locations.
222 		 */
223 		wmb();
224 
225 		/* Output a word */
226 		*to_u32_ptr++ = align_buffer;
227 	}
228 	if (length) {
229 		u8 *from_u8_ptr, *to_u8_ptr;
230 
231 		/* Set up to output the remaining data */
232 		align_buffer = 0;
233 		to_u8_ptr = (u8 *)&align_buffer;
234 		from_u8_ptr = (u8 *)from_u16_ptr;
235 
236 		/* Output the remaining data */
237 		for (; length > 0; length--)
238 			*to_u8_ptr++ = *from_u8_ptr++;
239 
240 		/* This barrier resolves occasional issues seen around
241 		 * cases where the data is not properly flushed out
242 		 * from the processor store buffers to the destination
243 		 * memory locations.
244 		 */
245 		wmb();
246 		*to_u32_ptr = align_buffer;
247 	}
248 }
249 
250 /**
251  * xemaclite_aligned_read - Read from 32-bit aligned to 16-bit aligned buffer
252  * @src_ptr:	Pointer to the 32-bit aligned source address
253  * @dest_ptr:	Pointer to the 16-bit aligned destination address
254  * @length:	Number bytes to read from source to destination
255  *
256  * This function reads data from a 32-bit aligned address in the EmacLite device
257  * to a 16-bit aligned buffer.
258  */
259 static void xemaclite_aligned_read(u32 *src_ptr, u8 *dest_ptr,
260 				   unsigned int length)
261 {
262 	u16 *to_u16_ptr, *from_u16_ptr;
263 	u32 *from_u32_ptr;
264 	u32 align_buffer;
265 
266 	from_u32_ptr = src_ptr;
267 	to_u16_ptr = (u16 *)dest_ptr;
268 
269 	for (; length > 3; length -= 4) {
270 		/* Copy each word into the temporary buffer */
271 		align_buffer = *from_u32_ptr++;
272 		from_u16_ptr = (u16 *)&align_buffer;
273 
274 		/* Read data from source */
275 		*to_u16_ptr++ = *from_u16_ptr++;
276 		*to_u16_ptr++ = *from_u16_ptr++;
277 	}
278 
279 	if (length) {
280 		u8 *to_u8_ptr, *from_u8_ptr;
281 
282 		/* Set up to read the remaining data */
283 		to_u8_ptr = (u8 *)to_u16_ptr;
284 		align_buffer = *from_u32_ptr++;
285 		from_u8_ptr = (u8 *)&align_buffer;
286 
287 		/* Read the remaining data */
288 		for (; length > 0; length--)
289 			*to_u8_ptr = *from_u8_ptr;
290 	}
291 }
292 
293 /**
294  * xemaclite_send_data - Send an Ethernet frame
295  * @drvdata:	Pointer to the Emaclite device private data
296  * @data:	Pointer to the data to be sent
297  * @byte_count:	Total frame size, including header
298  *
299  * This function checks if the Tx buffer of the Emaclite device is free to send
300  * data. If so, it fills the Tx buffer with data for transmission. Otherwise, it
301  * returns an error.
302  *
303  * Return:	0 upon success or -1 if the buffer(s) are full.
304  *
305  * Note:	The maximum Tx packet size can not be more than Ethernet header
306  *		(14 Bytes) + Maximum MTU (1500 bytes). This is excluding FCS.
307  */
308 static int xemaclite_send_data(struct net_local *drvdata, u8 *data,
309 			       unsigned int byte_count)
310 {
311 	u32 reg_data;
312 	void __iomem *addr;
313 
314 	/* Determine the expected Tx buffer address */
315 	addr = drvdata->base_addr + drvdata->next_tx_buf_to_use;
316 
317 	/* If the length is too large, truncate it */
318 	if (byte_count > ETH_FRAME_LEN)
319 		byte_count = ETH_FRAME_LEN;
320 
321 	/* Check if the expected buffer is available */
322 	reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET);
323 	if ((reg_data & (XEL_TSR_XMIT_BUSY_MASK |
324 	     XEL_TSR_XMIT_ACTIVE_MASK)) == 0) {
325 		/* Switch to next buffer if configured */
326 		if (drvdata->tx_ping_pong != 0)
327 			drvdata->next_tx_buf_to_use ^= XEL_BUFFER_OFFSET;
328 	} else if (drvdata->tx_ping_pong != 0) {
329 		/* If the expected buffer is full, try the other buffer,
330 		 * if it is configured in HW
331 		 */
332 
333 		addr = (void __iomem __force *)((uintptr_t __force)addr ^
334 						 XEL_BUFFER_OFFSET);
335 		reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET);
336 
337 		if ((reg_data & (XEL_TSR_XMIT_BUSY_MASK |
338 		     XEL_TSR_XMIT_ACTIVE_MASK)) != 0)
339 			return -1; /* Buffers were full, return failure */
340 	} else {
341 		return -1; /* Buffer was full, return failure */
342 	}
343 
344 	/* Write the frame to the buffer */
345 	xemaclite_aligned_write(data, (u32 __force *)addr, byte_count);
346 
347 	xemaclite_writel((byte_count & XEL_TPLR_LENGTH_MASK),
348 			 addr + XEL_TPLR_OFFSET);
349 
350 	/* Update the Tx Status Register to indicate that there is a
351 	 * frame to send. Set the XEL_TSR_XMIT_ACTIVE_MASK flag which
352 	 * is used by the interrupt handler to check whether a frame
353 	 * has been transmitted
354 	 */
355 	reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET);
356 	reg_data |= (XEL_TSR_XMIT_BUSY_MASK | XEL_TSR_XMIT_ACTIVE_MASK);
357 	xemaclite_writel(reg_data, addr + XEL_TSR_OFFSET);
358 
359 	return 0;
360 }
361 
362 /**
363  * xemaclite_recv_data - Receive a frame
364  * @drvdata:	Pointer to the Emaclite device private data
365  * @data:	Address where the data is to be received
366  * @maxlen:    Maximum supported ethernet packet length
367  *
368  * This function is intended to be called from the interrupt context or
369  * with a wrapper which waits for the receive frame to be available.
370  *
371  * Return:	Total number of bytes received
372  */
373 static u16 xemaclite_recv_data(struct net_local *drvdata, u8 *data, int maxlen)
374 {
375 	void __iomem *addr;
376 	u16 length, proto_type;
377 	u32 reg_data;
378 
379 	/* Determine the expected buffer address */
380 	addr = (drvdata->base_addr + drvdata->next_rx_buf_to_use);
381 
382 	/* Verify which buffer has valid data */
383 	reg_data = xemaclite_readl(addr + XEL_RSR_OFFSET);
384 
385 	if ((reg_data & XEL_RSR_RECV_DONE_MASK) == XEL_RSR_RECV_DONE_MASK) {
386 		if (drvdata->rx_ping_pong != 0)
387 			drvdata->next_rx_buf_to_use ^= XEL_BUFFER_OFFSET;
388 	} else {
389 		/* The instance is out of sync, try other buffer if other
390 		 * buffer is configured, return 0 otherwise. If the instance is
391 		 * out of sync, do not update the 'next_rx_buf_to_use' since it
392 		 * will correct on subsequent calls
393 		 */
394 		if (drvdata->rx_ping_pong != 0)
395 			addr = (void __iomem __force *)
396 				((uintptr_t __force)addr ^
397 				 XEL_BUFFER_OFFSET);
398 		else
399 			return 0;	/* No data was available */
400 
401 		/* Verify that buffer has valid data */
402 		reg_data = xemaclite_readl(addr + XEL_RSR_OFFSET);
403 		if ((reg_data & XEL_RSR_RECV_DONE_MASK) !=
404 		     XEL_RSR_RECV_DONE_MASK)
405 			return 0;	/* No data was available */
406 	}
407 
408 	/* Get the protocol type of the ethernet frame that arrived
409 	 */
410 	proto_type = ((ntohl(xemaclite_readl(addr + XEL_HEADER_OFFSET +
411 			XEL_RXBUFF_OFFSET)) >> XEL_HEADER_SHIFT) &
412 			XEL_RPLR_LENGTH_MASK);
413 
414 	/* Check if received ethernet frame is a raw ethernet frame
415 	 * or an IP packet or an ARP packet
416 	 */
417 	if (proto_type > ETH_DATA_LEN) {
418 		if (proto_type == ETH_P_IP) {
419 			length = ((ntohl(xemaclite_readl(addr +
420 					XEL_HEADER_IP_LENGTH_OFFSET +
421 					XEL_RXBUFF_OFFSET)) >>
422 					XEL_HEADER_SHIFT) &
423 					XEL_RPLR_LENGTH_MASK);
424 			length = min_t(u16, length, ETH_DATA_LEN);
425 			length += ETH_HLEN + ETH_FCS_LEN;
426 
427 		} else if (proto_type == ETH_P_ARP) {
428 			length = XEL_ARP_PACKET_SIZE + ETH_HLEN + ETH_FCS_LEN;
429 		} else {
430 			/* Field contains type other than IP or ARP, use max
431 			 * frame size and let user parse it
432 			 */
433 			length = ETH_FRAME_LEN + ETH_FCS_LEN;
434 		}
435 	} else {
436 		/* Use the length in the frame, plus the header and trailer */
437 		length = proto_type + ETH_HLEN + ETH_FCS_LEN;
438 	}
439 
440 	if (WARN_ON(length > maxlen))
441 		length = maxlen;
442 
443 	/* Read from the EmacLite device */
444 	xemaclite_aligned_read((u32 __force *)(addr + XEL_RXBUFF_OFFSET),
445 			       data, length);
446 
447 	/* Acknowledge the frame */
448 	reg_data = xemaclite_readl(addr + XEL_RSR_OFFSET);
449 	reg_data &= ~XEL_RSR_RECV_DONE_MASK;
450 	xemaclite_writel(reg_data, addr + XEL_RSR_OFFSET);
451 
452 	return length;
453 }
454 
455 /**
456  * xemaclite_update_address - Update the MAC address in the device
457  * @drvdata:	Pointer to the Emaclite device private data
458  * @address_ptr:Pointer to the MAC address (MAC address is a 48-bit value)
459  *
460  * Tx must be idle and Rx should be idle for deterministic results.
461  * It is recommended that this function should be called after the
462  * initialization and before transmission of any packets from the device.
463  * The MAC address can be programmed using any of the two transmit
464  * buffers (if configured).
465  */
466 static void xemaclite_update_address(struct net_local *drvdata,
467 				     const u8 *address_ptr)
468 {
469 	void __iomem *addr;
470 	u32 reg_data;
471 
472 	/* Determine the expected Tx buffer address */
473 	addr = drvdata->base_addr + drvdata->next_tx_buf_to_use;
474 
475 	xemaclite_aligned_write(address_ptr, (u32 __force *)addr, ETH_ALEN);
476 
477 	xemaclite_writel(ETH_ALEN, addr + XEL_TPLR_OFFSET);
478 
479 	/* Update the MAC address in the EmacLite */
480 	reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET);
481 	xemaclite_writel(reg_data | XEL_TSR_PROG_MAC_ADDR, addr + XEL_TSR_OFFSET);
482 
483 	/* Wait for EmacLite to finish with the MAC address update */
484 	while ((xemaclite_readl(addr + XEL_TSR_OFFSET) &
485 		XEL_TSR_PROG_MAC_ADDR) != 0)
486 		;
487 }
488 
489 /**
490  * xemaclite_set_mac_address - Set the MAC address for this device
491  * @dev:	Pointer to the network device instance
492  * @address:	Void pointer to the sockaddr structure
493  *
494  * This function copies the HW address from the sockaddr structure to the
495  * net_device structure and updates the address in HW.
496  *
497  * Return:	Error if the net device is busy or 0 if the addr is set
498  *		successfully
499  */
500 static int xemaclite_set_mac_address(struct net_device *dev, void *address)
501 {
502 	struct net_local *lp = netdev_priv(dev);
503 	struct sockaddr *addr = address;
504 
505 	if (netif_running(dev))
506 		return -EBUSY;
507 
508 	eth_hw_addr_set(dev, addr->sa_data);
509 	xemaclite_update_address(lp, dev->dev_addr);
510 	return 0;
511 }
512 
513 /**
514  * xemaclite_tx_timeout - Callback for Tx Timeout
515  * @dev:	Pointer to the network device
516  * @txqueue:	Unused
517  *
518  * This function is called when Tx time out occurs for Emaclite device.
519  */
520 static void xemaclite_tx_timeout(struct net_device *dev, unsigned int txqueue)
521 {
522 	struct net_local *lp = netdev_priv(dev);
523 	unsigned long flags;
524 
525 	dev_err(&lp->ndev->dev, "Exceeded transmit timeout of %lu ms\n",
526 		TX_TIMEOUT * 1000UL / HZ);
527 
528 	dev->stats.tx_errors++;
529 
530 	/* Reset the device */
531 	spin_lock_irqsave(&lp->reset_lock, flags);
532 
533 	/* Shouldn't really be necessary, but shouldn't hurt */
534 	netif_stop_queue(dev);
535 
536 	xemaclite_disable_interrupts(lp);
537 	xemaclite_enable_interrupts(lp);
538 
539 	if (lp->deferred_skb) {
540 		dev_kfree_skb_irq(lp->deferred_skb);
541 		lp->deferred_skb = NULL;
542 		dev->stats.tx_errors++;
543 	}
544 
545 	/* To exclude tx timeout */
546 	netif_trans_update(dev); /* prevent tx timeout */
547 
548 	/* We're all ready to go. Start the queue */
549 	netif_wake_queue(dev);
550 	spin_unlock_irqrestore(&lp->reset_lock, flags);
551 }
552 
553 /**********************/
554 /* Interrupt Handlers */
555 /**********************/
556 
557 /**
558  * xemaclite_tx_handler - Interrupt handler for frames sent
559  * @dev:	Pointer to the network device
560  *
561  * This function updates the number of packets transmitted and handles the
562  * deferred skb, if there is one.
563  */
564 static void xemaclite_tx_handler(struct net_device *dev)
565 {
566 	struct net_local *lp = netdev_priv(dev);
567 
568 	dev->stats.tx_packets++;
569 
570 	if (!lp->deferred_skb)
571 		return;
572 
573 	if (xemaclite_send_data(lp, (u8 *)lp->deferred_skb->data,
574 				lp->deferred_skb->len))
575 		return;
576 
577 	dev->stats.tx_bytes += lp->deferred_skb->len;
578 	dev_consume_skb_irq(lp->deferred_skb);
579 	lp->deferred_skb = NULL;
580 	netif_trans_update(dev); /* prevent tx timeout */
581 	netif_wake_queue(dev);
582 }
583 
584 /**
585  * xemaclite_rx_handler- Interrupt handler for frames received
586  * @dev:	Pointer to the network device
587  *
588  * This function allocates memory for a socket buffer, fills it with data
589  * received and hands it over to the TCP/IP stack.
590  */
591 static void xemaclite_rx_handler(struct net_device *dev)
592 {
593 	struct net_local *lp = netdev_priv(dev);
594 	struct sk_buff *skb;
595 	u32 len;
596 
597 	len = ETH_FRAME_LEN + ETH_FCS_LEN;
598 	skb = netdev_alloc_skb(dev, len + NET_IP_ALIGN);
599 	if (!skb) {
600 		/* Couldn't get memory. */
601 		dev->stats.rx_dropped++;
602 		dev_err(&lp->ndev->dev, "Could not allocate receive buffer\n");
603 		return;
604 	}
605 
606 	skb_reserve(skb, NET_IP_ALIGN);
607 
608 	len = xemaclite_recv_data(lp, (u8 *)skb->data, len);
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  * Return:	IRQ_HANDLED
635  *
636  * This function handles the Tx and Rx interrupts of the EmacLite device.
637  */
638 static irqreturn_t xemaclite_interrupt(int irq, void *dev_id)
639 {
640 	bool tx_complete = false;
641 	struct net_device *dev = dev_id;
642 	struct net_local *lp = netdev_priv(dev);
643 	void __iomem *base_addr = lp->base_addr;
644 	u32 tx_status;
645 
646 	/* Check if there is Rx Data available */
647 	if ((xemaclite_readl(base_addr + XEL_RSR_OFFSET) &
648 			 XEL_RSR_RECV_DONE_MASK) ||
649 	    (xemaclite_readl(base_addr + XEL_BUFFER_OFFSET + XEL_RSR_OFFSET)
650 			 & XEL_RSR_RECV_DONE_MASK))
651 
652 		xemaclite_rx_handler(dev);
653 
654 	/* Check if the Transmission for the first buffer is completed */
655 	tx_status = xemaclite_readl(base_addr + XEL_TSR_OFFSET);
656 	if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
657 	    (tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {
658 		tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
659 		xemaclite_writel(tx_status, base_addr + XEL_TSR_OFFSET);
660 
661 		tx_complete = true;
662 	}
663 
664 	/* Check if the Transmission for the second buffer is completed */
665 	tx_status = xemaclite_readl(base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);
666 	if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
667 	    (tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {
668 		tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
669 		xemaclite_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 	u32 val;
699 
700 	/* wait for the MDIO interface to not be busy or timeout
701 	 * after some time.
702 	 */
703 	return readx_poll_timeout(xemaclite_readl,
704 				  lp->base_addr + XEL_MDIOCTRL_OFFSET,
705 				  val, !(val & XEL_MDIOCTRL_MDIOSTS_MASK),
706 				  1000, 20000);
707 }
708 
709 /**
710  * xemaclite_mdio_read - Read from a given MII management register
711  * @bus:	the mii_bus struct
712  * @phy_id:	the phy address
713  * @reg:	register number to read from
714  *
715  * This function waits till the device is ready to accept a new MDIO
716  * request and then writes the phy address to the MDIO Address register
717  * and reads data from MDIO Read Data register, when its available.
718  *
719  * Return:	Value read from the MII management register
720  */
721 static int xemaclite_mdio_read(struct mii_bus *bus, int phy_id, int reg)
722 {
723 	struct net_local *lp = bus->priv;
724 	u32 ctrl_reg;
725 	u32 rc;
726 
727 	if (xemaclite_mdio_wait(lp))
728 		return -ETIMEDOUT;
729 
730 	/* Write the PHY address, register number and set the OP bit in the
731 	 * MDIO Address register. Set the Status bit in the MDIO Control
732 	 * register to start a MDIO read transaction.
733 	 */
734 	ctrl_reg = xemaclite_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
735 	xemaclite_writel(XEL_MDIOADDR_OP_MASK |
736 			 ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
737 			 lp->base_addr + XEL_MDIOADDR_OFFSET);
738 	xemaclite_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
739 			 lp->base_addr + XEL_MDIOCTRL_OFFSET);
740 
741 	if (xemaclite_mdio_wait(lp))
742 		return -ETIMEDOUT;
743 
744 	rc = xemaclite_readl(lp->base_addr + XEL_MDIORD_OFFSET);
745 
746 	dev_dbg(&lp->ndev->dev,
747 		"%s(phy_id=%i, reg=%x) == %x\n", __func__,
748 		phy_id, reg, rc);
749 
750 	return rc;
751 }
752 
753 /**
754  * xemaclite_mdio_write - Write to a given MII management register
755  * @bus:	the mii_bus struct
756  * @phy_id:	the phy address
757  * @reg:	register number to write to
758  * @val:	value to write to the register number specified by reg
759  *
760  * This function waits till the device is ready to accept a new MDIO
761  * request and then writes the val to the MDIO Write Data register.
762  *
763  * Return:      0 upon success or a negative error upon failure
764  */
765 static int xemaclite_mdio_write(struct mii_bus *bus, int phy_id, int reg,
766 				u16 val)
767 {
768 	struct net_local *lp = bus->priv;
769 	u32 ctrl_reg;
770 
771 	dev_dbg(&lp->ndev->dev,
772 		"%s(phy_id=%i, reg=%x, val=%x)\n", __func__,
773 		phy_id, reg, val);
774 
775 	if (xemaclite_mdio_wait(lp))
776 		return -ETIMEDOUT;
777 
778 	/* Write the PHY address, register number and clear the OP bit in the
779 	 * MDIO Address register and then write the value into the MDIO Write
780 	 * Data register. Finally, set the Status bit in the MDIO Control
781 	 * register to start a MDIO write transaction.
782 	 */
783 	ctrl_reg = xemaclite_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
784 	xemaclite_writel(~XEL_MDIOADDR_OP_MASK &
785 			 ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
786 			 lp->base_addr + XEL_MDIOADDR_OFFSET);
787 	xemaclite_writel(val, lp->base_addr + XEL_MDIOWR_OFFSET);
788 	xemaclite_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
789 			 lp->base_addr + XEL_MDIOCTRL_OFFSET);
790 
791 	return 0;
792 }
793 
794 /**
795  * xemaclite_mdio_setup - Register mii_bus for the Emaclite device
796  * @lp:		Pointer to the Emaclite device private data
797  * @dev:	Pointer to OF device structure
798  *
799  * This function enables MDIO bus in the Emaclite device and registers a
800  * mii_bus.
801  *
802  * Return:	0 upon success or a negative error upon failure
803  */
804 static int xemaclite_mdio_setup(struct net_local *lp, struct device *dev)
805 {
806 	struct mii_bus *bus;
807 	struct resource res;
808 	struct device_node *np = of_get_parent(lp->phy_node);
809 	struct device_node *npp;
810 	int rc, ret;
811 
812 	/* Don't register the MDIO bus if the phy_node or its parent node
813 	 * can't be found.
814 	 */
815 	if (!np) {
816 		dev_err(dev, "Failed to register mdio bus.\n");
817 		return -ENODEV;
818 	}
819 	npp = of_get_parent(np);
820 	ret = of_address_to_resource(npp, 0, &res);
821 	of_node_put(npp);
822 	if (ret) {
823 		dev_err(dev, "%s resource error!\n",
824 			dev->of_node->full_name);
825 		of_node_put(np);
826 		return ret;
827 	}
828 	if (lp->ndev->mem_start != res.start) {
829 		struct phy_device *phydev;
830 
831 		phydev = of_phy_find_device(lp->phy_node);
832 		if (!phydev)
833 			dev_info(dev,
834 				 "MDIO of the phy is not registered yet\n");
835 		else
836 			put_device(&phydev->mdio.dev);
837 		of_node_put(np);
838 		return 0;
839 	}
840 
841 	/* Enable the MDIO bus by asserting the enable bit in MDIO Control
842 	 * register.
843 	 */
844 	xemaclite_writel(XEL_MDIOCTRL_MDIOEN_MASK,
845 			 lp->base_addr + XEL_MDIOCTRL_OFFSET);
846 
847 	bus = mdiobus_alloc();
848 	if (!bus) {
849 		dev_err(dev, "Failed to allocate mdiobus\n");
850 		of_node_put(np);
851 		return -ENOMEM;
852 	}
853 
854 	snprintf(bus->id, MII_BUS_ID_SIZE, "%.8llx",
855 		 (unsigned long long)res.start);
856 	bus->priv = lp;
857 	bus->name = "Xilinx Emaclite MDIO";
858 	bus->read = xemaclite_mdio_read;
859 	bus->write = xemaclite_mdio_write;
860 	bus->parent = dev;
861 
862 	rc = of_mdiobus_register(bus, np);
863 	of_node_put(np);
864 	if (rc) {
865 		dev_err(dev, "Failed to register mdio bus.\n");
866 		goto err_register;
867 	}
868 
869 	lp->mii_bus = bus;
870 
871 	return 0;
872 
873 err_register:
874 	mdiobus_free(bus);
875 	return rc;
876 }
877 
878 /**
879  * xemaclite_adjust_link - Link state callback for the Emaclite device
880  * @ndev: pointer to net_device struct
881  *
882  * There's nothing in the Emaclite device to be configured when the link
883  * state changes. We just print the status.
884  */
885 static void xemaclite_adjust_link(struct net_device *ndev)
886 {
887 	struct net_local *lp = netdev_priv(ndev);
888 	struct phy_device *phy = lp->phy_dev;
889 	int link_state;
890 
891 	/* hash together the state values to decide if something has changed */
892 	link_state = phy->speed | (phy->duplex << 1) | phy->link;
893 
894 	if (lp->last_link != link_state) {
895 		lp->last_link = link_state;
896 		phy_print_status(phy);
897 	}
898 }
899 
900 /**
901  * xemaclite_open - Open the network device
902  * @dev:	Pointer to the network device
903  *
904  * This function sets the MAC address, requests an IRQ and enables interrupts
905  * for the Emaclite device and starts the Tx queue.
906  * It also connects to the phy device, if MDIO is included in Emaclite device.
907  *
908  * Return:	0 on success. -ENODEV, if PHY cannot be connected.
909  *		Non-zero error value on failure.
910  */
911 static int xemaclite_open(struct net_device *dev)
912 {
913 	struct net_local *lp = netdev_priv(dev);
914 	int retval;
915 
916 	/* Just to be safe, stop the device first */
917 	xemaclite_disable_interrupts(lp);
918 
919 	if (lp->phy_node) {
920 		lp->phy_dev = of_phy_connect(lp->ndev, lp->phy_node,
921 					     xemaclite_adjust_link, 0,
922 					     PHY_INTERFACE_MODE_MII);
923 		if (!lp->phy_dev) {
924 			dev_err(&lp->ndev->dev, "of_phy_connect() failed\n");
925 			return -ENODEV;
926 		}
927 
928 		/* EmacLite doesn't support giga-bit speeds */
929 		phy_set_max_speed(lp->phy_dev, SPEED_100);
930 		phy_start(lp->phy_dev);
931 	}
932 
933 	/* Set the MAC address each time opened */
934 	xemaclite_update_address(lp, dev->dev_addr);
935 
936 	/* Grab the IRQ */
937 	retval = request_irq(dev->irq, xemaclite_interrupt, 0, dev->name, dev);
938 	if (retval) {
939 		dev_err(&lp->ndev->dev, "Could not allocate interrupt %d\n",
940 			dev->irq);
941 		if (lp->phy_dev)
942 			phy_disconnect(lp->phy_dev);
943 		lp->phy_dev = NULL;
944 
945 		return retval;
946 	}
947 
948 	/* Enable Interrupts */
949 	xemaclite_enable_interrupts(lp);
950 
951 	/* We're ready to go */
952 	netif_start_queue(dev);
953 
954 	return 0;
955 }
956 
957 /**
958  * xemaclite_close - Close the network device
959  * @dev:	Pointer to the network device
960  *
961  * This function stops the Tx queue, disables interrupts and frees the IRQ for
962  * the Emaclite device.
963  * It also disconnects the phy device associated with the Emaclite device.
964  *
965  * Return:	0, always.
966  */
967 static int xemaclite_close(struct net_device *dev)
968 {
969 	struct net_local *lp = netdev_priv(dev);
970 
971 	netif_stop_queue(dev);
972 	xemaclite_disable_interrupts(lp);
973 	free_irq(dev->irq, dev);
974 
975 	if (lp->phy_dev)
976 		phy_disconnect(lp->phy_dev);
977 	lp->phy_dev = NULL;
978 
979 	return 0;
980 }
981 
982 /**
983  * xemaclite_send - Transmit a frame
984  * @orig_skb:	Pointer to the socket buffer to be transmitted
985  * @dev:	Pointer to the network device
986  *
987  * This function checks if the Tx buffer of the Emaclite device is free to send
988  * data. If so, it fills the Tx buffer with data from socket buffer data,
989  * updates the stats and frees the socket buffer. The Tx completion is signaled
990  * by an interrupt. If the Tx buffer isn't free, then the socket buffer is
991  * deferred and the Tx queue is stopped so that the deferred socket buffer can
992  * be transmitted when the Emaclite device is free to transmit data.
993  *
994  * Return:	NETDEV_TX_OK, always.
995  */
996 static netdev_tx_t
997 xemaclite_send(struct sk_buff *orig_skb, struct net_device *dev)
998 {
999 	struct net_local *lp = netdev_priv(dev);
1000 	struct sk_buff *new_skb;
1001 	unsigned int len;
1002 	unsigned long flags;
1003 
1004 	len = orig_skb->len;
1005 
1006 	new_skb = orig_skb;
1007 
1008 	spin_lock_irqsave(&lp->reset_lock, flags);
1009 	if (xemaclite_send_data(lp, (u8 *)new_skb->data, len) != 0) {
1010 		/* If the Emaclite Tx buffer is busy, stop the Tx queue and
1011 		 * defer the skb for transmission during the ISR, after the
1012 		 * current transmission is complete
1013 		 */
1014 		netif_stop_queue(dev);
1015 		lp->deferred_skb = new_skb;
1016 		/* Take the time stamp now, since we can't do this in an ISR. */
1017 		skb_tx_timestamp(new_skb);
1018 		spin_unlock_irqrestore(&lp->reset_lock, flags);
1019 		return NETDEV_TX_OK;
1020 	}
1021 	spin_unlock_irqrestore(&lp->reset_lock, flags);
1022 
1023 	skb_tx_timestamp(new_skb);
1024 
1025 	dev->stats.tx_bytes += len;
1026 	dev_consume_skb_any(new_skb);
1027 
1028 	return NETDEV_TX_OK;
1029 }
1030 
1031 /**
1032  * get_bool - Get a parameter from the OF device
1033  * @ofdev:	Pointer to OF device structure
1034  * @s:		Property to be retrieved
1035  *
1036  * This function looks for a property in the device node and returns the value
1037  * of the property if its found or 0 if the property is not found.
1038  *
1039  * Return:	Value of the parameter if the parameter is found, or 0 otherwise
1040  */
1041 static bool get_bool(struct platform_device *ofdev, const char *s)
1042 {
1043 	u32 *p = (u32 *)of_get_property(ofdev->dev.of_node, s, NULL);
1044 
1045 	if (!p) {
1046 		dev_warn(&ofdev->dev, "Parameter %s not found, defaulting to false\n", s);
1047 		return false;
1048 	}
1049 
1050 	return (bool)*p;
1051 }
1052 
1053 /**
1054  * xemaclite_ethtools_get_drvinfo - Get various Axi Emac Lite driver info
1055  * @ndev:       Pointer to net_device structure
1056  * @ed:         Pointer to ethtool_drvinfo structure
1057  *
1058  * This implements ethtool command for getting the driver information.
1059  * Issue "ethtool -i ethX" under linux prompt to execute this function.
1060  */
1061 static void xemaclite_ethtools_get_drvinfo(struct net_device *ndev,
1062 					   struct ethtool_drvinfo *ed)
1063 {
1064 	strscpy(ed->driver, DRIVER_NAME, sizeof(ed->driver));
1065 }
1066 
1067 static const struct ethtool_ops xemaclite_ethtool_ops = {
1068 	.get_drvinfo    = xemaclite_ethtools_get_drvinfo,
1069 	.get_link       = ethtool_op_get_link,
1070 	.get_link_ksettings = phy_ethtool_get_link_ksettings,
1071 	.set_link_ksettings = phy_ethtool_set_link_ksettings,
1072 };
1073 
1074 static const struct net_device_ops xemaclite_netdev_ops;
1075 
1076 /**
1077  * xemaclite_of_probe - Probe method for the Emaclite device.
1078  * @ofdev:	Pointer to OF device structure
1079  *
1080  * This function probes for the Emaclite device in the device tree.
1081  * It initializes the driver data structure and the hardware, sets the MAC
1082  * address and registers the network device.
1083  * It also registers a mii_bus for the Emaclite device, if MDIO is included
1084  * in the device.
1085  *
1086  * Return:	0, if the driver is bound to the Emaclite device, or
1087  *		a negative error if there is failure.
1088  */
1089 static int xemaclite_of_probe(struct platform_device *ofdev)
1090 {
1091 	struct resource *res;
1092 	struct net_device *ndev = NULL;
1093 	struct net_local *lp = NULL;
1094 	struct device *dev = &ofdev->dev;
1095 	struct clk *clkin;
1096 
1097 	int rc = 0;
1098 
1099 	dev_info(dev, "Device Tree Probing\n");
1100 
1101 	/* Create an ethernet device instance */
1102 	ndev = devm_alloc_etherdev(dev, sizeof(struct net_local));
1103 	if (!ndev)
1104 		return -ENOMEM;
1105 
1106 	dev_set_drvdata(dev, ndev);
1107 	SET_NETDEV_DEV(ndev, &ofdev->dev);
1108 
1109 	lp = netdev_priv(ndev);
1110 	lp->ndev = ndev;
1111 
1112 	/* Get IRQ for the device */
1113 	rc = platform_get_irq(ofdev, 0);
1114 	if (rc < 0)
1115 		return rc;
1116 
1117 	ndev->irq = rc;
1118 
1119 	lp->base_addr = devm_platform_get_and_ioremap_resource(ofdev, 0, &res);
1120 	if (IS_ERR(lp->base_addr))
1121 		return PTR_ERR(lp->base_addr);
1122 
1123 	ndev->mem_start = res->start;
1124 	ndev->mem_end = res->end;
1125 
1126 	spin_lock_init(&lp->reset_lock);
1127 	lp->next_tx_buf_to_use = 0x0;
1128 	lp->next_rx_buf_to_use = 0x0;
1129 	lp->tx_ping_pong = get_bool(ofdev, "xlnx,tx-ping-pong");
1130 	lp->rx_ping_pong = get_bool(ofdev, "xlnx,rx-ping-pong");
1131 
1132 	clkin = devm_clk_get_optional_enabled(&ofdev->dev, NULL);
1133 	if (IS_ERR(clkin))
1134 		return dev_err_probe(&ofdev->dev, PTR_ERR(clkin),
1135 				"Failed to get and enable clock from Device Tree\n");
1136 
1137 	rc = of_get_ethdev_address(ofdev->dev.of_node, ndev);
1138 	if (rc) {
1139 		dev_warn(dev, "No MAC address found, using random\n");
1140 		eth_hw_addr_random(ndev);
1141 	}
1142 
1143 	/* Clear the Tx CSR's in case this is a restart */
1144 	xemaclite_writel(0, lp->base_addr + XEL_TSR_OFFSET);
1145 	xemaclite_writel(0, lp->base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);
1146 
1147 	/* Set the MAC address in the EmacLite device */
1148 	xemaclite_update_address(lp, ndev->dev_addr);
1149 
1150 	lp->phy_node = of_parse_phandle(ofdev->dev.of_node, "phy-handle", 0);
1151 	xemaclite_mdio_setup(lp, &ofdev->dev);
1152 
1153 	dev_info(dev, "MAC address is now %pM\n", ndev->dev_addr);
1154 
1155 	ndev->netdev_ops = &xemaclite_netdev_ops;
1156 	ndev->ethtool_ops = &xemaclite_ethtool_ops;
1157 	ndev->flags &= ~IFF_MULTICAST;
1158 	ndev->watchdog_timeo = TX_TIMEOUT;
1159 
1160 	/* Finally, register the device */
1161 	rc = register_netdev(ndev);
1162 	if (rc) {
1163 		dev_err(dev,
1164 			"Cannot register network device, aborting\n");
1165 		goto put_node;
1166 	}
1167 
1168 	dev_info(dev,
1169 		 "Xilinx EmacLite at 0x%08lX mapped to 0x%p, irq=%d\n",
1170 		 (unsigned long __force)ndev->mem_start, lp->base_addr, ndev->irq);
1171 	return 0;
1172 
1173 put_node:
1174 	of_node_put(lp->phy_node);
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 static void xemaclite_of_remove(struct platform_device *of_dev)
1187 {
1188 	struct net_device *ndev = platform_get_drvdata(of_dev);
1189 
1190 	struct net_local *lp = netdev_priv(ndev);
1191 
1192 	/* Un-register the mii_bus, if configured */
1193 	if (lp->mii_bus) {
1194 		mdiobus_unregister(lp->mii_bus);
1195 		mdiobus_free(lp->mii_bus);
1196 		lp->mii_bus = NULL;
1197 	}
1198 
1199 	unregister_netdev(ndev);
1200 
1201 	of_node_put(lp->phy_node);
1202 	lp->phy_node = NULL;
1203 }
1204 
1205 #ifdef CONFIG_NET_POLL_CONTROLLER
1206 static void
1207 xemaclite_poll_controller(struct net_device *ndev)
1208 {
1209 	disable_irq(ndev->irq);
1210 	xemaclite_interrupt(ndev->irq, ndev);
1211 	enable_irq(ndev->irq);
1212 }
1213 #endif
1214 
1215 /* Ioctl MII Interface */
1216 static int xemaclite_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1217 {
1218 	if (!dev->phydev || !netif_running(dev))
1219 		return -EINVAL;
1220 
1221 	switch (cmd) {
1222 	case SIOCGMIIPHY:
1223 	case SIOCGMIIREG:
1224 	case SIOCSMIIREG:
1225 		return phy_mii_ioctl(dev->phydev, rq, cmd);
1226 	default:
1227 		return -EOPNOTSUPP;
1228 	}
1229 }
1230 
1231 static const struct net_device_ops xemaclite_netdev_ops = {
1232 	.ndo_open		= xemaclite_open,
1233 	.ndo_stop		= xemaclite_close,
1234 	.ndo_start_xmit		= xemaclite_send,
1235 	.ndo_set_mac_address	= xemaclite_set_mac_address,
1236 	.ndo_tx_timeout		= xemaclite_tx_timeout,
1237 	.ndo_eth_ioctl		= xemaclite_ioctl,
1238 #ifdef CONFIG_NET_POLL_CONTROLLER
1239 	.ndo_poll_controller = xemaclite_poll_controller,
1240 #endif
1241 };
1242 
1243 /* Match table for OF platform binding */
1244 static const struct of_device_id xemaclite_of_match[] = {
1245 	{ .compatible = "xlnx,opb-ethernetlite-1.01.a", },
1246 	{ .compatible = "xlnx,opb-ethernetlite-1.01.b", },
1247 	{ .compatible = "xlnx,xps-ethernetlite-1.00.a", },
1248 	{ .compatible = "xlnx,xps-ethernetlite-2.00.a", },
1249 	{ .compatible = "xlnx,xps-ethernetlite-2.01.a", },
1250 	{ .compatible = "xlnx,xps-ethernetlite-3.00.a", },
1251 	{ /* end of list */ },
1252 };
1253 MODULE_DEVICE_TABLE(of, xemaclite_of_match);
1254 
1255 static struct platform_driver xemaclite_of_driver = {
1256 	.driver = {
1257 		.name = DRIVER_NAME,
1258 		.of_match_table = xemaclite_of_match,
1259 	},
1260 	.probe		= xemaclite_of_probe,
1261 	.remove		= xemaclite_of_remove,
1262 };
1263 
1264 module_platform_driver(xemaclite_of_driver);
1265 
1266 MODULE_AUTHOR("Xilinx, Inc.");
1267 MODULE_DESCRIPTION("Xilinx Ethernet MAC Lite driver");
1268 MODULE_LICENSE("GPL");
1269