xref: /linux/drivers/net/ethernet/xilinx/xilinx_emaclite.c (revision 27b42557988d40340c9eb219f8f756f821f3649c)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Xilinx EmacLite Linux driver for the Xilinx Ethernet MAC Lite device.
4  *
5  * This is a new flat driver which is based on the original emac_lite
6  * driver from John Williams <john.williams@xilinx.com>.
7  *
8  * 2007 - 2013 (c) Xilinx, Inc.
9  */
10 
11 #include <linux/module.h>
12 #include <linux/uaccess.h>
13 #include <linux/netdevice.h>
14 #include <linux/etherdevice.h>
15 #include <linux/skbuff.h>
16 #include <linux/ethtool.h>
17 #include <linux/io.h>
18 #include <linux/slab.h>
19 #include <linux/of_address.h>
20 #include <linux/of_device.h>
21 #include <linux/of_platform.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 
95 
96 #define TX_TIMEOUT		(60 * HZ)	/* Tx timeout is 60 seconds. */
97 #define ALIGNMENT		4
98 
99 /* BUFFER_ALIGN(adr) calculates the number of bytes to the next alignment. */
100 #define BUFFER_ALIGN(adr) ((ALIGNMENT - ((u32)adr)) % ALIGNMENT)
101 
102 #ifdef __BIG_ENDIAN
103 #define xemaclite_readl		ioread32be
104 #define xemaclite_writel	iowrite32be
105 #else
106 #define xemaclite_readl		ioread32
107 #define xemaclite_writel	iowrite32
108 #endif
109 
110 /**
111  * struct net_local - Our private per device data
112  * @ndev:		instance of the network device
113  * @tx_ping_pong:	indicates whether Tx Pong buffer is configured in HW
114  * @rx_ping_pong:	indicates whether Rx Pong buffer is configured in HW
115  * @next_tx_buf_to_use:	next Tx buffer to write to
116  * @next_rx_buf_to_use:	next Rx buffer to read from
117  * @base_addr:		base address of the Emaclite device
118  * @reset_lock:		lock used for synchronization
119  * @deferred_skb:	holds an skb (for transmission at a later time) when the
120  *			Tx buffer is not free
121  * @phy_dev:		pointer to the PHY device
122  * @phy_node:		pointer to the PHY device node
123  * @mii_bus:		pointer to the MII bus
124  * @last_link:		last link status
125  */
126 struct net_local {
127 
128 	struct net_device *ndev;
129 
130 	bool tx_ping_pong;
131 	bool rx_ping_pong;
132 	u32 next_tx_buf_to_use;
133 	u32 next_rx_buf_to_use;
134 	void __iomem *base_addr;
135 
136 	spinlock_t reset_lock;
137 	struct sk_buff *deferred_skb;
138 
139 	struct phy_device *phy_dev;
140 	struct device_node *phy_node;
141 
142 	struct mii_bus *mii_bus;
143 
144 	int last_link;
145 };
146 
147 
148 /*************************/
149 /* EmacLite driver calls */
150 /*************************/
151 
152 /**
153  * xemaclite_enable_interrupts - Enable the interrupts for the EmacLite device
154  * @drvdata:	Pointer to the Emaclite device private data
155  *
156  * This function enables the Tx and Rx interrupts for the Emaclite device along
157  * with the Global Interrupt Enable.
158  */
159 static void xemaclite_enable_interrupts(struct net_local *drvdata)
160 {
161 	u32 reg_data;
162 
163 	/* Enable the Tx interrupts for the first Buffer */
164 	reg_data = xemaclite_readl(drvdata->base_addr + XEL_TSR_OFFSET);
165 	xemaclite_writel(reg_data | XEL_TSR_XMIT_IE_MASK,
166 			 drvdata->base_addr + XEL_TSR_OFFSET);
167 
168 	/* Enable the Rx interrupts for the first buffer */
169 	xemaclite_writel(XEL_RSR_RECV_IE_MASK, drvdata->base_addr + XEL_RSR_OFFSET);
170 
171 	/* Enable the Global Interrupt Enable */
172 	xemaclite_writel(XEL_GIER_GIE_MASK, drvdata->base_addr + XEL_GIER_OFFSET);
173 }
174 
175 /**
176  * xemaclite_disable_interrupts - Disable the interrupts for the EmacLite device
177  * @drvdata:	Pointer to the Emaclite device private data
178  *
179  * This function disables the Tx and Rx interrupts for the Emaclite device,
180  * along with the Global Interrupt Enable.
181  */
182 static void xemaclite_disable_interrupts(struct net_local *drvdata)
183 {
184 	u32 reg_data;
185 
186 	/* Disable the Global Interrupt Enable */
187 	xemaclite_writel(XEL_GIER_GIE_MASK, drvdata->base_addr + XEL_GIER_OFFSET);
188 
189 	/* Disable the Tx interrupts for the first buffer */
190 	reg_data = xemaclite_readl(drvdata->base_addr + XEL_TSR_OFFSET);
191 	xemaclite_writel(reg_data & (~XEL_TSR_XMIT_IE_MASK),
192 			 drvdata->base_addr + XEL_TSR_OFFSET);
193 
194 	/* Disable the Rx interrupts for the first buffer */
195 	reg_data = xemaclite_readl(drvdata->base_addr + XEL_RSR_OFFSET);
196 	xemaclite_writel(reg_data & (~XEL_RSR_RECV_IE_MASK),
197 			 drvdata->base_addr + XEL_RSR_OFFSET);
198 }
199 
200 /**
201  * xemaclite_aligned_write - Write from 16-bit aligned to 32-bit aligned address
202  * @src_ptr:	Void pointer to the 16-bit aligned source address
203  * @dest_ptr:	Pointer to the 32-bit aligned destination address
204  * @length:	Number bytes to write from source to destination
205  *
206  * This function writes data from a 16-bit aligned buffer to a 32-bit aligned
207  * address in the EmacLite device.
208  */
209 static void xemaclite_aligned_write(void *src_ptr, u32 *dest_ptr,
210 				    unsigned length)
211 {
212 	u32 align_buffer;
213 	u32 *to_u32_ptr;
214 	u16 *from_u16_ptr, *to_u16_ptr;
215 
216 	to_u32_ptr = dest_ptr;
217 	from_u16_ptr = src_ptr;
218 	align_buffer = 0;
219 
220 	for (; length > 3; length -= 4) {
221 		to_u16_ptr = (u16 *)&align_buffer;
222 		*to_u16_ptr++ = *from_u16_ptr++;
223 		*to_u16_ptr++ = *from_u16_ptr++;
224 
225 		/* This barrier resolves occasional issues seen around
226 		 * cases where the data is not properly flushed out
227 		 * from the processor store buffers to the destination
228 		 * memory locations.
229 		 */
230 		wmb();
231 
232 		/* Output a word */
233 		*to_u32_ptr++ = align_buffer;
234 	}
235 	if (length) {
236 		u8 *from_u8_ptr, *to_u8_ptr;
237 
238 		/* Set up to output the remaining data */
239 		align_buffer = 0;
240 		to_u8_ptr = (u8 *)&align_buffer;
241 		from_u8_ptr = (u8 *)from_u16_ptr;
242 
243 		/* Output the remaining data */
244 		for (; length > 0; length--)
245 			*to_u8_ptr++ = *from_u8_ptr++;
246 
247 		/* This barrier resolves occasional issues seen around
248 		 * cases where the data is not properly flushed out
249 		 * from the processor store buffers to the destination
250 		 * memory locations.
251 		 */
252 		wmb();
253 		*to_u32_ptr = align_buffer;
254 	}
255 }
256 
257 /**
258  * xemaclite_aligned_read - Read from 32-bit aligned to 16-bit aligned buffer
259  * @src_ptr:	Pointer to the 32-bit aligned source address
260  * @dest_ptr:	Pointer to the 16-bit aligned destination address
261  * @length:	Number bytes to read from source to destination
262  *
263  * This function reads data from a 32-bit aligned address in the EmacLite device
264  * to a 16-bit aligned buffer.
265  */
266 static void xemaclite_aligned_read(u32 *src_ptr, u8 *dest_ptr,
267 				   unsigned length)
268 {
269 	u16 *to_u16_ptr, *from_u16_ptr;
270 	u32 *from_u32_ptr;
271 	u32 align_buffer;
272 
273 	from_u32_ptr = src_ptr;
274 	to_u16_ptr = (u16 *)dest_ptr;
275 
276 	for (; length > 3; length -= 4) {
277 		/* Copy each word into the temporary buffer */
278 		align_buffer = *from_u32_ptr++;
279 		from_u16_ptr = (u16 *)&align_buffer;
280 
281 		/* Read data from source */
282 		*to_u16_ptr++ = *from_u16_ptr++;
283 		*to_u16_ptr++ = *from_u16_ptr++;
284 	}
285 
286 	if (length) {
287 		u8 *to_u8_ptr, *from_u8_ptr;
288 
289 		/* Set up to read the remaining data */
290 		to_u8_ptr = (u8 *)to_u16_ptr;
291 		align_buffer = *from_u32_ptr++;
292 		from_u8_ptr = (u8 *)&align_buffer;
293 
294 		/* Read the remaining data */
295 		for (; length > 0; length--)
296 			*to_u8_ptr = *from_u8_ptr;
297 	}
298 }
299 
300 /**
301  * xemaclite_send_data - Send an Ethernet frame
302  * @drvdata:	Pointer to the Emaclite device private data
303  * @data:	Pointer to the data to be sent
304  * @byte_count:	Total frame size, including header
305  *
306  * This function checks if the Tx buffer of the Emaclite device is free to send
307  * data. If so, it fills the Tx buffer with data for transmission. Otherwise, it
308  * returns an error.
309  *
310  * Return:	0 upon success or -1 if the buffer(s) are full.
311  *
312  * Note:	The maximum Tx packet size can not be more than Ethernet header
313  *		(14 Bytes) + Maximum MTU (1500 bytes). This is excluding FCS.
314  */
315 static int xemaclite_send_data(struct net_local *drvdata, u8 *data,
316 			       unsigned int byte_count)
317 {
318 	u32 reg_data;
319 	void __iomem *addr;
320 
321 	/* Determine the expected Tx buffer address */
322 	addr = drvdata->base_addr + drvdata->next_tx_buf_to_use;
323 
324 	/* If the length is too large, truncate it */
325 	if (byte_count > ETH_FRAME_LEN)
326 		byte_count = ETH_FRAME_LEN;
327 
328 	/* Check if the expected buffer is available */
329 	reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET);
330 	if ((reg_data & (XEL_TSR_XMIT_BUSY_MASK |
331 	     XEL_TSR_XMIT_ACTIVE_MASK)) == 0) {
332 
333 		/* Switch to next buffer if configured */
334 		if (drvdata->tx_ping_pong != 0)
335 			drvdata->next_tx_buf_to_use ^= XEL_BUFFER_OFFSET;
336 	} else if (drvdata->tx_ping_pong != 0) {
337 		/* If the expected buffer is full, try the other buffer,
338 		 * if it is configured in HW
339 		 */
340 
341 		addr = (void __iomem __force *)((u32 __force)addr ^
342 						 XEL_BUFFER_OFFSET);
343 		reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET);
344 
345 		if ((reg_data & (XEL_TSR_XMIT_BUSY_MASK |
346 		     XEL_TSR_XMIT_ACTIVE_MASK)) != 0)
347 			return -1; /* Buffers were full, return failure */
348 	} else
349 		return -1; /* Buffer was full, return failure */
350 
351 	/* Write the frame to the buffer */
352 	xemaclite_aligned_write(data, (u32 __force *)addr, byte_count);
353 
354 	xemaclite_writel((byte_count & XEL_TPLR_LENGTH_MASK),
355 			 addr + XEL_TPLR_OFFSET);
356 
357 	/* Update the Tx Status Register to indicate that there is a
358 	 * frame to send. Set the XEL_TSR_XMIT_ACTIVE_MASK flag which
359 	 * is used by the interrupt handler to check whether a frame
360 	 * has been transmitted
361 	 */
362 	reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET);
363 	reg_data |= (XEL_TSR_XMIT_BUSY_MASK | XEL_TSR_XMIT_ACTIVE_MASK);
364 	xemaclite_writel(reg_data, addr + XEL_TSR_OFFSET);
365 
366 	return 0;
367 }
368 
369 /**
370  * xemaclite_recv_data - Receive a frame
371  * @drvdata:	Pointer to the Emaclite device private data
372  * @data:	Address where the data is to be received
373  * @maxlen:    Maximum supported ethernet packet length
374  *
375  * This function is intended to be called from the interrupt context or
376  * with a wrapper which waits for the receive frame to be available.
377  *
378  * Return:	Total number of bytes received
379  */
380 static u16 xemaclite_recv_data(struct net_local *drvdata, u8 *data, int maxlen)
381 {
382 	void __iomem *addr;
383 	u16 length, proto_type;
384 	u32 reg_data;
385 
386 	/* Determine the expected buffer address */
387 	addr = (drvdata->base_addr + drvdata->next_rx_buf_to_use);
388 
389 	/* Verify which buffer has valid data */
390 	reg_data = xemaclite_readl(addr + XEL_RSR_OFFSET);
391 
392 	if ((reg_data & XEL_RSR_RECV_DONE_MASK) == XEL_RSR_RECV_DONE_MASK) {
393 		if (drvdata->rx_ping_pong != 0)
394 			drvdata->next_rx_buf_to_use ^= XEL_BUFFER_OFFSET;
395 	} else {
396 		/* The instance is out of sync, try other buffer if other
397 		 * buffer is configured, return 0 otherwise. If the instance is
398 		 * out of sync, do not update the 'next_rx_buf_to_use' since it
399 		 * will correct on subsequent calls
400 		 */
401 		if (drvdata->rx_ping_pong != 0)
402 			addr = (void __iomem __force *)((u32 __force)addr ^
403 							 XEL_BUFFER_OFFSET);
404 		else
405 			return 0;	/* No data was available */
406 
407 		/* Verify that buffer has valid data */
408 		reg_data = xemaclite_readl(addr + XEL_RSR_OFFSET);
409 		if ((reg_data & XEL_RSR_RECV_DONE_MASK) !=
410 		     XEL_RSR_RECV_DONE_MASK)
411 			return 0;	/* No data was available */
412 	}
413 
414 	/* Get the protocol type of the ethernet frame that arrived
415 	 */
416 	proto_type = ((ntohl(xemaclite_readl(addr + XEL_HEADER_OFFSET +
417 			XEL_RXBUFF_OFFSET)) >> XEL_HEADER_SHIFT) &
418 			XEL_RPLR_LENGTH_MASK);
419 
420 	/* Check if received ethernet frame is a raw ethernet frame
421 	 * or an IP packet or an ARP packet
422 	 */
423 	if (proto_type > ETH_DATA_LEN) {
424 
425 		if (proto_type == ETH_P_IP) {
426 			length = ((ntohl(xemaclite_readl(addr +
427 					XEL_HEADER_IP_LENGTH_OFFSET +
428 					XEL_RXBUFF_OFFSET)) >>
429 					XEL_HEADER_SHIFT) &
430 					XEL_RPLR_LENGTH_MASK);
431 			length = min_t(u16, length, ETH_DATA_LEN);
432 			length += ETH_HLEN + ETH_FCS_LEN;
433 
434 		} else if (proto_type == ETH_P_ARP)
435 			length = XEL_ARP_PACKET_SIZE + ETH_HLEN + ETH_FCS_LEN;
436 		else
437 			/* Field contains type other than IP or ARP, use max
438 			 * frame size and let user parse it
439 			 */
440 			length = ETH_FRAME_LEN + ETH_FCS_LEN;
441 	} else
442 		/* Use the length in the frame, plus the header and trailer */
443 		length = proto_type + ETH_HLEN + ETH_FCS_LEN;
444 
445 	if (WARN_ON(length > maxlen))
446 		length = maxlen;
447 
448 	/* Read from the EmacLite device */
449 	xemaclite_aligned_read((u32 __force *)(addr + XEL_RXBUFF_OFFSET),
450 				data, length);
451 
452 	/* Acknowledge the frame */
453 	reg_data = xemaclite_readl(addr + XEL_RSR_OFFSET);
454 	reg_data &= ~XEL_RSR_RECV_DONE_MASK;
455 	xemaclite_writel(reg_data, addr + XEL_RSR_OFFSET);
456 
457 	return length;
458 }
459 
460 /**
461  * xemaclite_update_address - Update the MAC address in the device
462  * @drvdata:	Pointer to the Emaclite device private data
463  * @address_ptr:Pointer to the MAC address (MAC address is a 48-bit value)
464  *
465  * Tx must be idle and Rx should be idle for deterministic results.
466  * It is recommended that this function should be called after the
467  * initialization and before transmission of any packets from the device.
468  * The MAC address can be programmed using any of the two transmit
469  * buffers (if configured).
470  */
471 static void xemaclite_update_address(struct net_local *drvdata,
472 				     u8 *address_ptr)
473 {
474 	void __iomem *addr;
475 	u32 reg_data;
476 
477 	/* Determine the expected Tx buffer address */
478 	addr = drvdata->base_addr + drvdata->next_tx_buf_to_use;
479 
480 	xemaclite_aligned_write(address_ptr, (u32 __force *)addr, ETH_ALEN);
481 
482 	xemaclite_writel(ETH_ALEN, addr + XEL_TPLR_OFFSET);
483 
484 	/* Update the MAC address in the EmacLite */
485 	reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET);
486 	xemaclite_writel(reg_data | XEL_TSR_PROG_MAC_ADDR, addr + XEL_TSR_OFFSET);
487 
488 	/* Wait for EmacLite to finish with the MAC address update */
489 	while ((xemaclite_readl(addr + XEL_TSR_OFFSET) &
490 		XEL_TSR_PROG_MAC_ADDR) != 0)
491 		;
492 }
493 
494 /**
495  * xemaclite_set_mac_address - Set the MAC address for this device
496  * @dev:	Pointer to the network device instance
497  * @address:	Void pointer to the sockaddr structure
498  *
499  * This function copies the HW address from the sockaddr strucutre to the
500  * net_device structure and updates the address in HW.
501  *
502  * Return:	Error if the net device is busy or 0 if the addr is set
503  *		successfully
504  */
505 static int xemaclite_set_mac_address(struct net_device *dev, void *address)
506 {
507 	struct net_local *lp = netdev_priv(dev);
508 	struct sockaddr *addr = address;
509 
510 	if (netif_running(dev))
511 		return -EBUSY;
512 
513 	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
514 	xemaclite_update_address(lp, dev->dev_addr);
515 	return 0;
516 }
517 
518 /**
519  * xemaclite_tx_timeout - Callback for Tx Timeout
520  * @dev:	Pointer to the network device
521  * @txqueue:	Unused
522  *
523  * This function is called when Tx time out occurs for Emaclite device.
524  */
525 static void xemaclite_tx_timeout(struct net_device *dev, unsigned int txqueue)
526 {
527 	struct net_local *lp = netdev_priv(dev);
528 	unsigned long flags;
529 
530 	dev_err(&lp->ndev->dev, "Exceeded transmit timeout of %lu ms\n",
531 		TX_TIMEOUT * 1000UL / HZ);
532 
533 	dev->stats.tx_errors++;
534 
535 	/* Reset the device */
536 	spin_lock_irqsave(&lp->reset_lock, flags);
537 
538 	/* Shouldn't really be necessary, but shouldn't hurt */
539 	netif_stop_queue(dev);
540 
541 	xemaclite_disable_interrupts(lp);
542 	xemaclite_enable_interrupts(lp);
543 
544 	if (lp->deferred_skb) {
545 		dev_kfree_skb(lp->deferred_skb);
546 		lp->deferred_skb = NULL;
547 		dev->stats.tx_errors++;
548 	}
549 
550 	/* To exclude tx timeout */
551 	netif_trans_update(dev); /* prevent tx timeout */
552 
553 	/* We're all ready to go. Start the queue */
554 	netif_wake_queue(dev);
555 	spin_unlock_irqrestore(&lp->reset_lock, flags);
556 }
557 
558 /**********************/
559 /* Interrupt Handlers */
560 /**********************/
561 
562 /**
563  * xemaclite_tx_handler - Interrupt handler for frames sent
564  * @dev:	Pointer to the network device
565  *
566  * This function updates the number of packets transmitted and handles the
567  * deferred skb, if there is one.
568  */
569 static void xemaclite_tx_handler(struct net_device *dev)
570 {
571 	struct net_local *lp = netdev_priv(dev);
572 
573 	dev->stats.tx_packets++;
574 
575 	if (!lp->deferred_skb)
576 		return;
577 
578 	if (xemaclite_send_data(lp, (u8 *)lp->deferred_skb->data,
579 				lp->deferred_skb->len))
580 		return;
581 
582 	dev->stats.tx_bytes += lp->deferred_skb->len;
583 	dev_consume_skb_irq(lp->deferred_skb);
584 	lp->deferred_skb = NULL;
585 	netif_trans_update(dev); /* prevent tx timeout */
586 	netif_wake_queue(dev);
587 }
588 
589 /**
590  * xemaclite_rx_handler- Interrupt handler for frames received
591  * @dev:	Pointer to the network device
592  *
593  * This function allocates memory for a socket buffer, fills it with data
594  * received and hands it over to the TCP/IP stack.
595  */
596 static void xemaclite_rx_handler(struct net_device *dev)
597 {
598 	struct net_local *lp = netdev_priv(dev);
599 	struct sk_buff *skb;
600 	unsigned int align;
601 	u32 len;
602 
603 	len = ETH_FRAME_LEN + ETH_FCS_LEN;
604 	skb = netdev_alloc_skb(dev, len + ALIGNMENT);
605 	if (!skb) {
606 		/* Couldn't get memory. */
607 		dev->stats.rx_dropped++;
608 		dev_err(&lp->ndev->dev, "Could not allocate receive buffer\n");
609 		return;
610 	}
611 
612 	/* A new skb should have the data halfword aligned, but this code is
613 	 * here just in case that isn't true. Calculate how many
614 	 * bytes we should reserve to get the data to start on a word
615 	 * boundary
616 	 */
617 	align = BUFFER_ALIGN(skb->data);
618 	if (align)
619 		skb_reserve(skb, align);
620 
621 	skb_reserve(skb, 2);
622 
623 	len = xemaclite_recv_data(lp, (u8 *)skb->data, len);
624 
625 	if (!len) {
626 		dev->stats.rx_errors++;
627 		dev_kfree_skb_irq(skb);
628 		return;
629 	}
630 
631 	skb_put(skb, len);	/* Tell the skb how much data we got */
632 
633 	skb->protocol = eth_type_trans(skb, dev);
634 	skb_checksum_none_assert(skb);
635 
636 	dev->stats.rx_packets++;
637 	dev->stats.rx_bytes += len;
638 
639 	if (!skb_defer_rx_timestamp(skb))
640 		netif_rx(skb);	/* Send the packet upstream */
641 }
642 
643 /**
644  * xemaclite_interrupt - Interrupt handler for this driver
645  * @irq:	Irq of the Emaclite device
646  * @dev_id:	Void pointer to the network device instance used as callback
647  *		reference
648  *
649  * Return:	IRQ_HANDLED
650  *
651  * This function handles the Tx and Rx interrupts of the EmacLite device.
652  */
653 static irqreturn_t xemaclite_interrupt(int irq, void *dev_id)
654 {
655 	bool tx_complete = false;
656 	struct net_device *dev = dev_id;
657 	struct net_local *lp = netdev_priv(dev);
658 	void __iomem *base_addr = lp->base_addr;
659 	u32 tx_status;
660 
661 	/* Check if there is Rx Data available */
662 	if ((xemaclite_readl(base_addr + XEL_RSR_OFFSET) &
663 			 XEL_RSR_RECV_DONE_MASK) ||
664 	    (xemaclite_readl(base_addr + XEL_BUFFER_OFFSET + XEL_RSR_OFFSET)
665 			 & XEL_RSR_RECV_DONE_MASK))
666 
667 		xemaclite_rx_handler(dev);
668 
669 	/* Check if the Transmission for the first buffer is completed */
670 	tx_status = xemaclite_readl(base_addr + XEL_TSR_OFFSET);
671 	if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
672 		(tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {
673 
674 		tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
675 		xemaclite_writel(tx_status, base_addr + XEL_TSR_OFFSET);
676 
677 		tx_complete = true;
678 	}
679 
680 	/* Check if the Transmission for the second buffer is completed */
681 	tx_status = xemaclite_readl(base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);
682 	if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
683 		(tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {
684 
685 		tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
686 		xemaclite_writel(tx_status, base_addr + XEL_BUFFER_OFFSET +
687 				 XEL_TSR_OFFSET);
688 
689 		tx_complete = true;
690 	}
691 
692 	/* If there was a Tx interrupt, call the Tx Handler */
693 	if (tx_complete != 0)
694 		xemaclite_tx_handler(dev);
695 
696 	return IRQ_HANDLED;
697 }
698 
699 /**********************/
700 /* MDIO Bus functions */
701 /**********************/
702 
703 /**
704  * xemaclite_mdio_wait - Wait for the MDIO to be ready to use
705  * @lp:		Pointer to the Emaclite device private data
706  *
707  * This function waits till the device is ready to accept a new MDIO
708  * request.
709  *
710  * Return:	0 for success or ETIMEDOUT for a timeout
711  */
712 
713 static int xemaclite_mdio_wait(struct net_local *lp)
714 {
715 	u32 val;
716 
717 	/* wait for the MDIO interface to not be busy or timeout
718 	 * after some time.
719 	 */
720 	return readx_poll_timeout(xemaclite_readl,
721 				  lp->base_addr + XEL_MDIOCTRL_OFFSET,
722 				  val, !(val & XEL_MDIOCTRL_MDIOSTS_MASK),
723 				  1000, 20000);
724 }
725 
726 /**
727  * xemaclite_mdio_read - Read from a given MII management register
728  * @bus:	the mii_bus struct
729  * @phy_id:	the phy address
730  * @reg:	register number to read from
731  *
732  * This function waits till the device is ready to accept a new MDIO
733  * request and then writes the phy address to the MDIO Address register
734  * and reads data from MDIO Read Data register, when its available.
735  *
736  * Return:	Value read from the MII management register
737  */
738 static int xemaclite_mdio_read(struct mii_bus *bus, int phy_id, int reg)
739 {
740 	struct net_local *lp = bus->priv;
741 	u32 ctrl_reg;
742 	u32 rc;
743 
744 	if (xemaclite_mdio_wait(lp))
745 		return -ETIMEDOUT;
746 
747 	/* Write the PHY address, register number and set the OP bit in the
748 	 * MDIO Address register. Set the Status bit in the MDIO Control
749 	 * register to start a MDIO read transaction.
750 	 */
751 	ctrl_reg = xemaclite_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
752 	xemaclite_writel(XEL_MDIOADDR_OP_MASK |
753 			 ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
754 			 lp->base_addr + XEL_MDIOADDR_OFFSET);
755 	xemaclite_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
756 			 lp->base_addr + XEL_MDIOCTRL_OFFSET);
757 
758 	if (xemaclite_mdio_wait(lp))
759 		return -ETIMEDOUT;
760 
761 	rc = xemaclite_readl(lp->base_addr + XEL_MDIORD_OFFSET);
762 
763 	dev_dbg(&lp->ndev->dev,
764 		"%s(phy_id=%i, reg=%x) == %x\n", __func__,
765 		phy_id, reg, rc);
766 
767 	return rc;
768 }
769 
770 /**
771  * xemaclite_mdio_write - Write to a given MII management register
772  * @bus:	the mii_bus struct
773  * @phy_id:	the phy address
774  * @reg:	register number to write to
775  * @val:	value to write to the register number specified by reg
776  *
777  * This function waits till the device is ready to accept a new MDIO
778  * request and then writes the val to the MDIO Write Data register.
779  *
780  * Return:      0 upon success or a negative error upon failure
781  */
782 static int xemaclite_mdio_write(struct mii_bus *bus, int phy_id, int reg,
783 				u16 val)
784 {
785 	struct net_local *lp = bus->priv;
786 	u32 ctrl_reg;
787 
788 	dev_dbg(&lp->ndev->dev,
789 		"%s(phy_id=%i, reg=%x, val=%x)\n", __func__,
790 		phy_id, reg, val);
791 
792 	if (xemaclite_mdio_wait(lp))
793 		return -ETIMEDOUT;
794 
795 	/* Write the PHY address, register number and clear the OP bit in the
796 	 * MDIO Address register and then write the value into the MDIO Write
797 	 * Data register. Finally, set the Status bit in the MDIO Control
798 	 * register to start a MDIO write transaction.
799 	 */
800 	ctrl_reg = xemaclite_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
801 	xemaclite_writel(~XEL_MDIOADDR_OP_MASK &
802 			 ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
803 			 lp->base_addr + XEL_MDIOADDR_OFFSET);
804 	xemaclite_writel(val, lp->base_addr + XEL_MDIOWR_OFFSET);
805 	xemaclite_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
806 			 lp->base_addr + XEL_MDIOCTRL_OFFSET);
807 
808 	return 0;
809 }
810 
811 /**
812  * xemaclite_mdio_setup - Register mii_bus for the Emaclite device
813  * @lp:		Pointer to the Emaclite device private data
814  * @dev:	Pointer to OF device structure
815  *
816  * This function enables MDIO bus in the Emaclite device and registers a
817  * mii_bus.
818  *
819  * Return:	0 upon success or a negative error upon failure
820  */
821 static int xemaclite_mdio_setup(struct net_local *lp, struct device *dev)
822 {
823 	struct mii_bus *bus;
824 	int rc;
825 	struct resource res;
826 	struct device_node *np = of_get_parent(lp->phy_node);
827 	struct device_node *npp;
828 
829 	/* Don't register the MDIO bus if the phy_node or its parent node
830 	 * can't be found.
831 	 */
832 	if (!np) {
833 		dev_err(dev, "Failed to register mdio bus.\n");
834 		return -ENODEV;
835 	}
836 	npp = of_get_parent(np);
837 
838 	of_address_to_resource(npp, 0, &res);
839 	if (lp->ndev->mem_start != res.start) {
840 		struct phy_device *phydev;
841 		phydev = of_phy_find_device(lp->phy_node);
842 		if (!phydev)
843 			dev_info(dev,
844 				 "MDIO of the phy is not registered yet\n");
845 		else
846 			put_device(&phydev->mdio.dev);
847 		return 0;
848 	}
849 
850 	/* Enable the MDIO bus by asserting the enable bit in MDIO Control
851 	 * register.
852 	 */
853 	xemaclite_writel(XEL_MDIOCTRL_MDIOEN_MASK,
854 			 lp->base_addr + XEL_MDIOCTRL_OFFSET);
855 
856 	bus = mdiobus_alloc();
857 	if (!bus) {
858 		dev_err(dev, "Failed to allocate mdiobus\n");
859 		return -ENOMEM;
860 	}
861 
862 	snprintf(bus->id, MII_BUS_ID_SIZE, "%.8llx",
863 		 (unsigned long long)res.start);
864 	bus->priv = lp;
865 	bus->name = "Xilinx Emaclite MDIO";
866 	bus->read = xemaclite_mdio_read;
867 	bus->write = xemaclite_mdio_write;
868 	bus->parent = dev;
869 
870 	rc = of_mdiobus_register(bus, np);
871 	if (rc) {
872 		dev_err(dev, "Failed to register mdio bus.\n");
873 		goto err_register;
874 	}
875 
876 	lp->mii_bus = bus;
877 
878 	return 0;
879 
880 err_register:
881 	mdiobus_free(bus);
882 	return rc;
883 }
884 
885 /**
886  * xemaclite_adjust_link - Link state callback for the Emaclite device
887  * @ndev: pointer to net_device struct
888  *
889  * There's nothing in the Emaclite device to be configured when the link
890  * state changes. We just print the status.
891  */
892 static void xemaclite_adjust_link(struct net_device *ndev)
893 {
894 	struct net_local *lp = netdev_priv(ndev);
895 	struct phy_device *phy = lp->phy_dev;
896 	int link_state;
897 
898 	/* hash together the state values to decide if something has changed */
899 	link_state = phy->speed | (phy->duplex << 1) | phy->link;
900 
901 	if (lp->last_link != link_state) {
902 		lp->last_link = link_state;
903 		phy_print_status(phy);
904 	}
905 }
906 
907 /**
908  * xemaclite_open - Open the network device
909  * @dev:	Pointer to the network device
910  *
911  * This function sets the MAC address, requests an IRQ and enables interrupts
912  * for the Emaclite device and starts the Tx queue.
913  * It also connects to the phy device, if MDIO is included in Emaclite device.
914  *
915  * Return:	0 on success. -ENODEV, if PHY cannot be connected.
916  *		Non-zero error value on failure.
917  */
918 static int xemaclite_open(struct net_device *dev)
919 {
920 	struct net_local *lp = netdev_priv(dev);
921 	int retval;
922 
923 	/* Just to be safe, stop the device first */
924 	xemaclite_disable_interrupts(lp);
925 
926 	if (lp->phy_node) {
927 		u32 bmcr;
928 
929 		lp->phy_dev = of_phy_connect(lp->ndev, lp->phy_node,
930 					     xemaclite_adjust_link, 0,
931 					     PHY_INTERFACE_MODE_MII);
932 		if (!lp->phy_dev) {
933 			dev_err(&lp->ndev->dev, "of_phy_connect() failed\n");
934 			return -ENODEV;
935 		}
936 
937 		/* EmacLite doesn't support giga-bit speeds */
938 		phy_set_max_speed(lp->phy_dev, SPEED_100);
939 
940 		/* Don't advertise 1000BASE-T Full/Half duplex speeds */
941 		phy_write(lp->phy_dev, MII_CTRL1000, 0);
942 
943 		/* Advertise only 10 and 100mbps full/half duplex speeds */
944 		phy_write(lp->phy_dev, MII_ADVERTISE, ADVERTISE_ALL |
945 			  ADVERTISE_CSMA);
946 
947 		/* Restart auto negotiation */
948 		bmcr = phy_read(lp->phy_dev, MII_BMCR);
949 		bmcr |= (BMCR_ANENABLE | BMCR_ANRESTART);
950 		phy_write(lp->phy_dev, MII_BMCR, bmcr);
951 
952 		phy_start(lp->phy_dev);
953 	}
954 
955 	/* Set the MAC address each time opened */
956 	xemaclite_update_address(lp, dev->dev_addr);
957 
958 	/* Grab the IRQ */
959 	retval = request_irq(dev->irq, xemaclite_interrupt, 0, dev->name, dev);
960 	if (retval) {
961 		dev_err(&lp->ndev->dev, "Could not allocate interrupt %d\n",
962 			dev->irq);
963 		if (lp->phy_dev)
964 			phy_disconnect(lp->phy_dev);
965 		lp->phy_dev = NULL;
966 
967 		return retval;
968 	}
969 
970 	/* Enable Interrupts */
971 	xemaclite_enable_interrupts(lp);
972 
973 	/* We're ready to go */
974 	netif_start_queue(dev);
975 
976 	return 0;
977 }
978 
979 /**
980  * xemaclite_close - Close the network device
981  * @dev:	Pointer to the network device
982  *
983  * This function stops the Tx queue, disables interrupts and frees the IRQ for
984  * the Emaclite device.
985  * It also disconnects the phy device associated with the Emaclite device.
986  *
987  * Return:	0, always.
988  */
989 static int xemaclite_close(struct net_device *dev)
990 {
991 	struct net_local *lp = netdev_priv(dev);
992 
993 	netif_stop_queue(dev);
994 	xemaclite_disable_interrupts(lp);
995 	free_irq(dev->irq, dev);
996 
997 	if (lp->phy_dev)
998 		phy_disconnect(lp->phy_dev);
999 	lp->phy_dev = NULL;
1000 
1001 	return 0;
1002 }
1003 
1004 /**
1005  * xemaclite_send - Transmit a frame
1006  * @orig_skb:	Pointer to the socket buffer to be transmitted
1007  * @dev:	Pointer to the network device
1008  *
1009  * This function checks if the Tx buffer of the Emaclite device is free to send
1010  * data. If so, it fills the Tx buffer with data from socket buffer data,
1011  * updates the stats and frees the socket buffer. The Tx completion is signaled
1012  * by an interrupt. If the Tx buffer isn't free, then the socket buffer is
1013  * deferred and the Tx queue is stopped so that the deferred socket buffer can
1014  * be transmitted when the Emaclite device is free to transmit data.
1015  *
1016  * Return:	NETDEV_TX_OK, always.
1017  */
1018 static netdev_tx_t
1019 xemaclite_send(struct sk_buff *orig_skb, struct net_device *dev)
1020 {
1021 	struct net_local *lp = netdev_priv(dev);
1022 	struct sk_buff *new_skb;
1023 	unsigned int len;
1024 	unsigned long flags;
1025 
1026 	len = orig_skb->len;
1027 
1028 	new_skb = orig_skb;
1029 
1030 	spin_lock_irqsave(&lp->reset_lock, flags);
1031 	if (xemaclite_send_data(lp, (u8 *)new_skb->data, len) != 0) {
1032 		/* If the Emaclite Tx buffer is busy, stop the Tx queue and
1033 		 * defer the skb for transmission during the ISR, after the
1034 		 * current transmission is complete
1035 		 */
1036 		netif_stop_queue(dev);
1037 		lp->deferred_skb = new_skb;
1038 		/* Take the time stamp now, since we can't do this in an ISR. */
1039 		skb_tx_timestamp(new_skb);
1040 		spin_unlock_irqrestore(&lp->reset_lock, flags);
1041 		return NETDEV_TX_OK;
1042 	}
1043 	spin_unlock_irqrestore(&lp->reset_lock, flags);
1044 
1045 	skb_tx_timestamp(new_skb);
1046 
1047 	dev->stats.tx_bytes += len;
1048 	dev_consume_skb_any(new_skb);
1049 
1050 	return NETDEV_TX_OK;
1051 }
1052 
1053 /**
1054  * get_bool - Get a parameter from the OF device
1055  * @ofdev:	Pointer to OF device structure
1056  * @s:		Property to be retrieved
1057  *
1058  * This function looks for a property in the device node and returns the value
1059  * of the property if its found or 0 if the property is not found.
1060  *
1061  * Return:	Value of the parameter if the parameter is found, or 0 otherwise
1062  */
1063 static bool get_bool(struct platform_device *ofdev, const char *s)
1064 {
1065 	u32 *p = (u32 *)of_get_property(ofdev->dev.of_node, s, NULL);
1066 
1067 	if (!p) {
1068 		dev_warn(&ofdev->dev, "Parameter %s not found, defaulting to false\n", s);
1069 		return false;
1070 	}
1071 
1072 	return (bool)*p;
1073 }
1074 
1075 /**
1076  * xemaclite_ethtools_get_drvinfo - Get various Axi Emac Lite driver info
1077  * @ndev:       Pointer to net_device structure
1078  * @ed:         Pointer to ethtool_drvinfo structure
1079  *
1080  * This implements ethtool command for getting the driver information.
1081  * Issue "ethtool -i ethX" under linux prompt to execute this function.
1082  */
1083 static void xemaclite_ethtools_get_drvinfo(struct net_device *ndev,
1084 					   struct ethtool_drvinfo *ed)
1085 {
1086 	strlcpy(ed->driver, DRIVER_NAME, sizeof(ed->driver));
1087 }
1088 
1089 static const struct ethtool_ops xemaclite_ethtool_ops = {
1090 	.get_drvinfo    = xemaclite_ethtools_get_drvinfo,
1091 	.get_link       = ethtool_op_get_link,
1092 	.get_link_ksettings = phy_ethtool_get_link_ksettings,
1093 	.set_link_ksettings = phy_ethtool_set_link_ksettings,
1094 };
1095 
1096 static const struct net_device_ops xemaclite_netdev_ops;
1097 
1098 /**
1099  * xemaclite_of_probe - Probe method for the Emaclite device.
1100  * @ofdev:	Pointer to OF device structure
1101  *
1102  * This function probes for the Emaclite device in the device tree.
1103  * It initializes the driver data structure and the hardware, sets the MAC
1104  * address and registers the network device.
1105  * It also registers a mii_bus for the Emaclite device, if MDIO is included
1106  * in the device.
1107  *
1108  * Return:	0, if the driver is bound to the Emaclite device, or
1109  *		a negative error if there is failure.
1110  */
1111 static int xemaclite_of_probe(struct platform_device *ofdev)
1112 {
1113 	struct resource *res;
1114 	struct net_device *ndev = NULL;
1115 	struct net_local *lp = NULL;
1116 	struct device *dev = &ofdev->dev;
1117 	const void *mac_address;
1118 
1119 	int rc = 0;
1120 
1121 	dev_info(dev, "Device Tree Probing\n");
1122 
1123 	/* Create an ethernet device instance */
1124 	ndev = alloc_etherdev(sizeof(struct net_local));
1125 	if (!ndev)
1126 		return -ENOMEM;
1127 
1128 	dev_set_drvdata(dev, ndev);
1129 	SET_NETDEV_DEV(ndev, &ofdev->dev);
1130 
1131 	lp = netdev_priv(ndev);
1132 	lp->ndev = ndev;
1133 
1134 	/* Get IRQ for the device */
1135 	res = platform_get_resource(ofdev, IORESOURCE_IRQ, 0);
1136 	if (!res) {
1137 		dev_err(dev, "no IRQ found\n");
1138 		rc = -ENXIO;
1139 		goto error;
1140 	}
1141 
1142 	ndev->irq = res->start;
1143 
1144 	res = platform_get_resource(ofdev, IORESOURCE_MEM, 0);
1145 	lp->base_addr = devm_ioremap_resource(&ofdev->dev, res);
1146 	if (IS_ERR(lp->base_addr)) {
1147 		rc = PTR_ERR(lp->base_addr);
1148 		goto error;
1149 	}
1150 
1151 	ndev->mem_start = res->start;
1152 	ndev->mem_end = res->end;
1153 
1154 	spin_lock_init(&lp->reset_lock);
1155 	lp->next_tx_buf_to_use = 0x0;
1156 	lp->next_rx_buf_to_use = 0x0;
1157 	lp->tx_ping_pong = get_bool(ofdev, "xlnx,tx-ping-pong");
1158 	lp->rx_ping_pong = get_bool(ofdev, "xlnx,rx-ping-pong");
1159 	mac_address = of_get_mac_address(ofdev->dev.of_node);
1160 
1161 	if (!IS_ERR(mac_address)) {
1162 		/* Set the MAC address. */
1163 		ether_addr_copy(ndev->dev_addr, mac_address);
1164 	} else {
1165 		dev_warn(dev, "No MAC address found, using random\n");
1166 		eth_hw_addr_random(ndev);
1167 	}
1168 
1169 	/* Clear the Tx CSR's in case this is a restart */
1170 	xemaclite_writel(0, lp->base_addr + XEL_TSR_OFFSET);
1171 	xemaclite_writel(0, lp->base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);
1172 
1173 	/* Set the MAC address in the EmacLite device */
1174 	xemaclite_update_address(lp, ndev->dev_addr);
1175 
1176 	lp->phy_node = of_parse_phandle(ofdev->dev.of_node, "phy-handle", 0);
1177 	xemaclite_mdio_setup(lp, &ofdev->dev);
1178 
1179 	dev_info(dev, "MAC address is now %pM\n", ndev->dev_addr);
1180 
1181 	ndev->netdev_ops = &xemaclite_netdev_ops;
1182 	ndev->ethtool_ops = &xemaclite_ethtool_ops;
1183 	ndev->flags &= ~IFF_MULTICAST;
1184 	ndev->watchdog_timeo = TX_TIMEOUT;
1185 
1186 	/* Finally, register the device */
1187 	rc = register_netdev(ndev);
1188 	if (rc) {
1189 		dev_err(dev,
1190 			"Cannot register network device, aborting\n");
1191 		goto error;
1192 	}
1193 
1194 	dev_info(dev,
1195 		 "Xilinx EmacLite at 0x%08X mapped to 0x%08X, irq=%d\n",
1196 		 (unsigned int __force)ndev->mem_start,
1197 		 (unsigned int __force)lp->base_addr, ndev->irq);
1198 	return 0;
1199 
1200 error:
1201 	free_netdev(ndev);
1202 	return rc;
1203 }
1204 
1205 /**
1206  * xemaclite_of_remove - Unbind the driver from the Emaclite device.
1207  * @of_dev:	Pointer to OF device structure
1208  *
1209  * This function is called if a device is physically removed from the system or
1210  * if the driver module is being unloaded. It frees any resources allocated to
1211  * the device.
1212  *
1213  * Return:	0, always.
1214  */
1215 static int xemaclite_of_remove(struct platform_device *of_dev)
1216 {
1217 	struct net_device *ndev = platform_get_drvdata(of_dev);
1218 
1219 	struct net_local *lp = netdev_priv(ndev);
1220 
1221 	/* Un-register the mii_bus, if configured */
1222 	if (lp->mii_bus) {
1223 		mdiobus_unregister(lp->mii_bus);
1224 		mdiobus_free(lp->mii_bus);
1225 		lp->mii_bus = NULL;
1226 	}
1227 
1228 	unregister_netdev(ndev);
1229 
1230 	of_node_put(lp->phy_node);
1231 	lp->phy_node = NULL;
1232 
1233 	free_netdev(ndev);
1234 
1235 	return 0;
1236 }
1237 
1238 #ifdef CONFIG_NET_POLL_CONTROLLER
1239 static void
1240 xemaclite_poll_controller(struct net_device *ndev)
1241 {
1242 	disable_irq(ndev->irq);
1243 	xemaclite_interrupt(ndev->irq, ndev);
1244 	enable_irq(ndev->irq);
1245 }
1246 #endif
1247 
1248 /* Ioctl MII Interface */
1249 static int xemaclite_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1250 {
1251 	if (!dev->phydev || !netif_running(dev))
1252 		return -EINVAL;
1253 
1254 	switch (cmd) {
1255 	case SIOCGMIIPHY:
1256 	case SIOCGMIIREG:
1257 	case SIOCSMIIREG:
1258 		return phy_mii_ioctl(dev->phydev, rq, cmd);
1259 	default:
1260 		return -EOPNOTSUPP;
1261 	}
1262 }
1263 
1264 static const struct net_device_ops xemaclite_netdev_ops = {
1265 	.ndo_open		= xemaclite_open,
1266 	.ndo_stop		= xemaclite_close,
1267 	.ndo_start_xmit		= xemaclite_send,
1268 	.ndo_set_mac_address	= xemaclite_set_mac_address,
1269 	.ndo_tx_timeout		= xemaclite_tx_timeout,
1270 	.ndo_do_ioctl		= xemaclite_ioctl,
1271 #ifdef CONFIG_NET_POLL_CONTROLLER
1272 	.ndo_poll_controller = xemaclite_poll_controller,
1273 #endif
1274 };
1275 
1276 /* Match table for OF platform binding */
1277 static const struct of_device_id xemaclite_of_match[] = {
1278 	{ .compatible = "xlnx,opb-ethernetlite-1.01.a", },
1279 	{ .compatible = "xlnx,opb-ethernetlite-1.01.b", },
1280 	{ .compatible = "xlnx,xps-ethernetlite-1.00.a", },
1281 	{ .compatible = "xlnx,xps-ethernetlite-2.00.a", },
1282 	{ .compatible = "xlnx,xps-ethernetlite-2.01.a", },
1283 	{ .compatible = "xlnx,xps-ethernetlite-3.00.a", },
1284 	{ /* end of list */ },
1285 };
1286 MODULE_DEVICE_TABLE(of, xemaclite_of_match);
1287 
1288 static struct platform_driver xemaclite_of_driver = {
1289 	.driver = {
1290 		.name = DRIVER_NAME,
1291 		.of_match_table = xemaclite_of_match,
1292 	},
1293 	.probe		= xemaclite_of_probe,
1294 	.remove		= xemaclite_of_remove,
1295 };
1296 
1297 module_platform_driver(xemaclite_of_driver);
1298 
1299 MODULE_AUTHOR("Xilinx, Inc.");
1300 MODULE_DESCRIPTION("Xilinx Ethernet MAC Lite driver");
1301 MODULE_LICENSE("GPL");
1302