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 - ((uintptr_t)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 *)((uintptr_t __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 *)
403 				((uintptr_t __force)addr ^
404 				 XEL_BUFFER_OFFSET);
405 		else
406 			return 0;	/* No data was available */
407 
408 		/* Verify that buffer has valid data */
409 		reg_data = xemaclite_readl(addr + XEL_RSR_OFFSET);
410 		if ((reg_data & XEL_RSR_RECV_DONE_MASK) !=
411 		     XEL_RSR_RECV_DONE_MASK)
412 			return 0;	/* No data was available */
413 	}
414 
415 	/* Get the protocol type of the ethernet frame that arrived
416 	 */
417 	proto_type = ((ntohl(xemaclite_readl(addr + XEL_HEADER_OFFSET +
418 			XEL_RXBUFF_OFFSET)) >> XEL_HEADER_SHIFT) &
419 			XEL_RPLR_LENGTH_MASK);
420 
421 	/* Check if received ethernet frame is a raw ethernet frame
422 	 * or an IP packet or an ARP packet
423 	 */
424 	if (proto_type > ETH_DATA_LEN) {
425 
426 		if (proto_type == ETH_P_IP) {
427 			length = ((ntohl(xemaclite_readl(addr +
428 					XEL_HEADER_IP_LENGTH_OFFSET +
429 					XEL_RXBUFF_OFFSET)) >>
430 					XEL_HEADER_SHIFT) &
431 					XEL_RPLR_LENGTH_MASK);
432 			length = min_t(u16, length, ETH_DATA_LEN);
433 			length += ETH_HLEN + ETH_FCS_LEN;
434 
435 		} else if (proto_type == ETH_P_ARP)
436 			length = XEL_ARP_PACKET_SIZE + ETH_HLEN + ETH_FCS_LEN;
437 		else
438 			/* Field contains type other than IP or ARP, use max
439 			 * frame size and let user parse it
440 			 */
441 			length = ETH_FRAME_LEN + ETH_FCS_LEN;
442 	} else
443 		/* Use the length in the frame, plus the header and trailer */
444 		length = proto_type + ETH_HLEN + ETH_FCS_LEN;
445 
446 	if (WARN_ON(length > maxlen))
447 		length = maxlen;
448 
449 	/* Read from the EmacLite device */
450 	xemaclite_aligned_read((u32 __force *)(addr + XEL_RXBUFF_OFFSET),
451 				data, length);
452 
453 	/* Acknowledge the frame */
454 	reg_data = xemaclite_readl(addr + XEL_RSR_OFFSET);
455 	reg_data &= ~XEL_RSR_RECV_DONE_MASK;
456 	xemaclite_writel(reg_data, addr + XEL_RSR_OFFSET);
457 
458 	return length;
459 }
460 
461 /**
462  * xemaclite_update_address - Update the MAC address in the device
463  * @drvdata:	Pointer to the Emaclite device private data
464  * @address_ptr:Pointer to the MAC address (MAC address is a 48-bit value)
465  *
466  * Tx must be idle and Rx should be idle for deterministic results.
467  * It is recommended that this function should be called after the
468  * initialization and before transmission of any packets from the device.
469  * The MAC address can be programmed using any of the two transmit
470  * buffers (if configured).
471  */
472 static void xemaclite_update_address(struct net_local *drvdata,
473 				     u8 *address_ptr)
474 {
475 	void __iomem *addr;
476 	u32 reg_data;
477 
478 	/* Determine the expected Tx buffer address */
479 	addr = drvdata->base_addr + drvdata->next_tx_buf_to_use;
480 
481 	xemaclite_aligned_write(address_ptr, (u32 __force *)addr, ETH_ALEN);
482 
483 	xemaclite_writel(ETH_ALEN, addr + XEL_TPLR_OFFSET);
484 
485 	/* Update the MAC address in the EmacLite */
486 	reg_data = xemaclite_readl(addr + XEL_TSR_OFFSET);
487 	xemaclite_writel(reg_data | XEL_TSR_PROG_MAC_ADDR, addr + XEL_TSR_OFFSET);
488 
489 	/* Wait for EmacLite to finish with the MAC address update */
490 	while ((xemaclite_readl(addr + XEL_TSR_OFFSET) &
491 		XEL_TSR_PROG_MAC_ADDR) != 0)
492 		;
493 }
494 
495 /**
496  * xemaclite_set_mac_address - Set the MAC address for this device
497  * @dev:	Pointer to the network device instance
498  * @address:	Void pointer to the sockaddr structure
499  *
500  * This function copies the HW address from the sockaddr strucutre to the
501  * net_device structure and updates the address in HW.
502  *
503  * Return:	Error if the net device is busy or 0 if the addr is set
504  *		successfully
505  */
506 static int xemaclite_set_mac_address(struct net_device *dev, void *address)
507 {
508 	struct net_local *lp = netdev_priv(dev);
509 	struct sockaddr *addr = address;
510 
511 	if (netif_running(dev))
512 		return -EBUSY;
513 
514 	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
515 	xemaclite_update_address(lp, dev->dev_addr);
516 	return 0;
517 }
518 
519 /**
520  * xemaclite_tx_timeout - Callback for Tx Timeout
521  * @dev:	Pointer to the network device
522  * @txqueue:	Unused
523  *
524  * This function is called when Tx time out occurs for Emaclite device.
525  */
526 static void xemaclite_tx_timeout(struct net_device *dev, unsigned int txqueue)
527 {
528 	struct net_local *lp = netdev_priv(dev);
529 	unsigned long flags;
530 
531 	dev_err(&lp->ndev->dev, "Exceeded transmit timeout of %lu ms\n",
532 		TX_TIMEOUT * 1000UL / HZ);
533 
534 	dev->stats.tx_errors++;
535 
536 	/* Reset the device */
537 	spin_lock_irqsave(&lp->reset_lock, flags);
538 
539 	/* Shouldn't really be necessary, but shouldn't hurt */
540 	netif_stop_queue(dev);
541 
542 	xemaclite_disable_interrupts(lp);
543 	xemaclite_enable_interrupts(lp);
544 
545 	if (lp->deferred_skb) {
546 		dev_kfree_skb(lp->deferred_skb);
547 		lp->deferred_skb = NULL;
548 		dev->stats.tx_errors++;
549 	}
550 
551 	/* To exclude tx timeout */
552 	netif_trans_update(dev); /* prevent tx timeout */
553 
554 	/* We're all ready to go. Start the queue */
555 	netif_wake_queue(dev);
556 	spin_unlock_irqrestore(&lp->reset_lock, flags);
557 }
558 
559 /**********************/
560 /* Interrupt Handlers */
561 /**********************/
562 
563 /**
564  * xemaclite_tx_handler - Interrupt handler for frames sent
565  * @dev:	Pointer to the network device
566  *
567  * This function updates the number of packets transmitted and handles the
568  * deferred skb, if there is one.
569  */
570 static void xemaclite_tx_handler(struct net_device *dev)
571 {
572 	struct net_local *lp = netdev_priv(dev);
573 
574 	dev->stats.tx_packets++;
575 
576 	if (!lp->deferred_skb)
577 		return;
578 
579 	if (xemaclite_send_data(lp, (u8 *)lp->deferred_skb->data,
580 				lp->deferred_skb->len))
581 		return;
582 
583 	dev->stats.tx_bytes += lp->deferred_skb->len;
584 	dev_consume_skb_irq(lp->deferred_skb);
585 	lp->deferred_skb = NULL;
586 	netif_trans_update(dev); /* prevent tx timeout */
587 	netif_wake_queue(dev);
588 }
589 
590 /**
591  * xemaclite_rx_handler- Interrupt handler for frames received
592  * @dev:	Pointer to the network device
593  *
594  * This function allocates memory for a socket buffer, fills it with data
595  * received and hands it over to the TCP/IP stack.
596  */
597 static void xemaclite_rx_handler(struct net_device *dev)
598 {
599 	struct net_local *lp = netdev_priv(dev);
600 	struct sk_buff *skb;
601 	unsigned int align;
602 	u32 len;
603 
604 	len = ETH_FRAME_LEN + ETH_FCS_LEN;
605 	skb = netdev_alloc_skb(dev, len + ALIGNMENT);
606 	if (!skb) {
607 		/* Couldn't get memory. */
608 		dev->stats.rx_dropped++;
609 		dev_err(&lp->ndev->dev, "Could not allocate receive buffer\n");
610 		return;
611 	}
612 
613 	/* A new skb should have the data halfword aligned, but this code is
614 	 * here just in case that isn't true. Calculate how many
615 	 * bytes we should reserve to get the data to start on a word
616 	 * boundary
617 	 */
618 	align = BUFFER_ALIGN(skb->data);
619 	if (align)
620 		skb_reserve(skb, align);
621 
622 	skb_reserve(skb, 2);
623 
624 	len = xemaclite_recv_data(lp, (u8 *)skb->data, len);
625 
626 	if (!len) {
627 		dev->stats.rx_errors++;
628 		dev_kfree_skb_irq(skb);
629 		return;
630 	}
631 
632 	skb_put(skb, len);	/* Tell the skb how much data we got */
633 
634 	skb->protocol = eth_type_trans(skb, dev);
635 	skb_checksum_none_assert(skb);
636 
637 	dev->stats.rx_packets++;
638 	dev->stats.rx_bytes += len;
639 
640 	if (!skb_defer_rx_timestamp(skb))
641 		netif_rx(skb);	/* Send the packet upstream */
642 }
643 
644 /**
645  * xemaclite_interrupt - Interrupt handler for this driver
646  * @irq:	Irq of the Emaclite device
647  * @dev_id:	Void pointer to the network device instance used as callback
648  *		reference
649  *
650  * Return:	IRQ_HANDLED
651  *
652  * This function handles the Tx and Rx interrupts of the EmacLite device.
653  */
654 static irqreturn_t xemaclite_interrupt(int irq, void *dev_id)
655 {
656 	bool tx_complete = false;
657 	struct net_device *dev = dev_id;
658 	struct net_local *lp = netdev_priv(dev);
659 	void __iomem *base_addr = lp->base_addr;
660 	u32 tx_status;
661 
662 	/* Check if there is Rx Data available */
663 	if ((xemaclite_readl(base_addr + XEL_RSR_OFFSET) &
664 			 XEL_RSR_RECV_DONE_MASK) ||
665 	    (xemaclite_readl(base_addr + XEL_BUFFER_OFFSET + XEL_RSR_OFFSET)
666 			 & XEL_RSR_RECV_DONE_MASK))
667 
668 		xemaclite_rx_handler(dev);
669 
670 	/* Check if the Transmission for the first buffer is completed */
671 	tx_status = xemaclite_readl(base_addr + XEL_TSR_OFFSET);
672 	if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
673 		(tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {
674 
675 		tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
676 		xemaclite_writel(tx_status, base_addr + XEL_TSR_OFFSET);
677 
678 		tx_complete = true;
679 	}
680 
681 	/* Check if the Transmission for the second buffer is completed */
682 	tx_status = xemaclite_readl(base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);
683 	if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
684 		(tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {
685 
686 		tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
687 		xemaclite_writel(tx_status, base_addr + XEL_BUFFER_OFFSET +
688 				 XEL_TSR_OFFSET);
689 
690 		tx_complete = true;
691 	}
692 
693 	/* If there was a Tx interrupt, call the Tx Handler */
694 	if (tx_complete != 0)
695 		xemaclite_tx_handler(dev);
696 
697 	return IRQ_HANDLED;
698 }
699 
700 /**********************/
701 /* MDIO Bus functions */
702 /**********************/
703 
704 /**
705  * xemaclite_mdio_wait - Wait for the MDIO to be ready to use
706  * @lp:		Pointer to the Emaclite device private data
707  *
708  * This function waits till the device is ready to accept a new MDIO
709  * request.
710  *
711  * Return:	0 for success or ETIMEDOUT for a timeout
712  */
713 
714 static int xemaclite_mdio_wait(struct net_local *lp)
715 {
716 	u32 val;
717 
718 	/* wait for the MDIO interface to not be busy or timeout
719 	 * after some time.
720 	 */
721 	return readx_poll_timeout(xemaclite_readl,
722 				  lp->base_addr + XEL_MDIOCTRL_OFFSET,
723 				  val, !(val & XEL_MDIOCTRL_MDIOSTS_MASK),
724 				  1000, 20000);
725 }
726 
727 /**
728  * xemaclite_mdio_read - Read from a given MII management register
729  * @bus:	the mii_bus struct
730  * @phy_id:	the phy address
731  * @reg:	register number to read from
732  *
733  * This function waits till the device is ready to accept a new MDIO
734  * request and then writes the phy address to the MDIO Address register
735  * and reads data from MDIO Read Data register, when its available.
736  *
737  * Return:	Value read from the MII management register
738  */
739 static int xemaclite_mdio_read(struct mii_bus *bus, int phy_id, int reg)
740 {
741 	struct net_local *lp = bus->priv;
742 	u32 ctrl_reg;
743 	u32 rc;
744 
745 	if (xemaclite_mdio_wait(lp))
746 		return -ETIMEDOUT;
747 
748 	/* Write the PHY address, register number and set the OP bit in the
749 	 * MDIO Address register. Set the Status bit in the MDIO Control
750 	 * register to start a MDIO read transaction.
751 	 */
752 	ctrl_reg = xemaclite_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
753 	xemaclite_writel(XEL_MDIOADDR_OP_MASK |
754 			 ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
755 			 lp->base_addr + XEL_MDIOADDR_OFFSET);
756 	xemaclite_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
757 			 lp->base_addr + XEL_MDIOCTRL_OFFSET);
758 
759 	if (xemaclite_mdio_wait(lp))
760 		return -ETIMEDOUT;
761 
762 	rc = xemaclite_readl(lp->base_addr + XEL_MDIORD_OFFSET);
763 
764 	dev_dbg(&lp->ndev->dev,
765 		"%s(phy_id=%i, reg=%x) == %x\n", __func__,
766 		phy_id, reg, rc);
767 
768 	return rc;
769 }
770 
771 /**
772  * xemaclite_mdio_write - Write to a given MII management register
773  * @bus:	the mii_bus struct
774  * @phy_id:	the phy address
775  * @reg:	register number to write to
776  * @val:	value to write to the register number specified by reg
777  *
778  * This function waits till the device is ready to accept a new MDIO
779  * request and then writes the val to the MDIO Write Data register.
780  *
781  * Return:      0 upon success or a negative error upon failure
782  */
783 static int xemaclite_mdio_write(struct mii_bus *bus, int phy_id, int reg,
784 				u16 val)
785 {
786 	struct net_local *lp = bus->priv;
787 	u32 ctrl_reg;
788 
789 	dev_dbg(&lp->ndev->dev,
790 		"%s(phy_id=%i, reg=%x, val=%x)\n", __func__,
791 		phy_id, reg, val);
792 
793 	if (xemaclite_mdio_wait(lp))
794 		return -ETIMEDOUT;
795 
796 	/* Write the PHY address, register number and clear the OP bit in the
797 	 * MDIO Address register and then write the value into the MDIO Write
798 	 * Data register. Finally, set the Status bit in the MDIO Control
799 	 * register to start a MDIO write transaction.
800 	 */
801 	ctrl_reg = xemaclite_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
802 	xemaclite_writel(~XEL_MDIOADDR_OP_MASK &
803 			 ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
804 			 lp->base_addr + XEL_MDIOADDR_OFFSET);
805 	xemaclite_writel(val, lp->base_addr + XEL_MDIOWR_OFFSET);
806 	xemaclite_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
807 			 lp->base_addr + XEL_MDIOCTRL_OFFSET);
808 
809 	return 0;
810 }
811 
812 /**
813  * xemaclite_mdio_setup - Register mii_bus for the Emaclite device
814  * @lp:		Pointer to the Emaclite device private data
815  * @dev:	Pointer to OF device structure
816  *
817  * This function enables MDIO bus in the Emaclite device and registers a
818  * mii_bus.
819  *
820  * Return:	0 upon success or a negative error upon failure
821  */
822 static int xemaclite_mdio_setup(struct net_local *lp, struct device *dev)
823 {
824 	struct mii_bus *bus;
825 	int rc;
826 	struct resource res;
827 	struct device_node *np = of_get_parent(lp->phy_node);
828 	struct device_node *npp;
829 
830 	/* Don't register the MDIO bus if the phy_node or its parent node
831 	 * can't be found.
832 	 */
833 	if (!np) {
834 		dev_err(dev, "Failed to register mdio bus.\n");
835 		return -ENODEV;
836 	}
837 	npp = of_get_parent(np);
838 
839 	of_address_to_resource(npp, 0, &res);
840 	if (lp->ndev->mem_start != res.start) {
841 		struct phy_device *phydev;
842 		phydev = of_phy_find_device(lp->phy_node);
843 		if (!phydev)
844 			dev_info(dev,
845 				 "MDIO of the phy is not registered yet\n");
846 		else
847 			put_device(&phydev->mdio.dev);
848 		return 0;
849 	}
850 
851 	/* Enable the MDIO bus by asserting the enable bit in MDIO Control
852 	 * register.
853 	 */
854 	xemaclite_writel(XEL_MDIOCTRL_MDIOEN_MASK,
855 			 lp->base_addr + XEL_MDIOCTRL_OFFSET);
856 
857 	bus = mdiobus_alloc();
858 	if (!bus) {
859 		dev_err(dev, "Failed to allocate mdiobus\n");
860 		return -ENOMEM;
861 	}
862 
863 	snprintf(bus->id, MII_BUS_ID_SIZE, "%.8llx",
864 		 (unsigned long long)res.start);
865 	bus->priv = lp;
866 	bus->name = "Xilinx Emaclite MDIO";
867 	bus->read = xemaclite_mdio_read;
868 	bus->write = xemaclite_mdio_write;
869 	bus->parent = dev;
870 
871 	rc = of_mdiobus_register(bus, np);
872 	if (rc) {
873 		dev_err(dev, "Failed to register mdio bus.\n");
874 		goto err_register;
875 	}
876 
877 	lp->mii_bus = bus;
878 
879 	return 0;
880 
881 err_register:
882 	mdiobus_free(bus);
883 	return rc;
884 }
885 
886 /**
887  * xemaclite_adjust_link - Link state callback for the Emaclite device
888  * @ndev: pointer to net_device struct
889  *
890  * There's nothing in the Emaclite device to be configured when the link
891  * state changes. We just print the status.
892  */
893 static void xemaclite_adjust_link(struct net_device *ndev)
894 {
895 	struct net_local *lp = netdev_priv(ndev);
896 	struct phy_device *phy = lp->phy_dev;
897 	int link_state;
898 
899 	/* hash together the state values to decide if something has changed */
900 	link_state = phy->speed | (phy->duplex << 1) | phy->link;
901 
902 	if (lp->last_link != link_state) {
903 		lp->last_link = link_state;
904 		phy_print_status(phy);
905 	}
906 }
907 
908 /**
909  * xemaclite_open - Open the network device
910  * @dev:	Pointer to the network device
911  *
912  * This function sets the MAC address, requests an IRQ and enables interrupts
913  * for the Emaclite device and starts the Tx queue.
914  * It also connects to the phy device, if MDIO is included in Emaclite device.
915  *
916  * Return:	0 on success. -ENODEV, if PHY cannot be connected.
917  *		Non-zero error value on failure.
918  */
919 static int xemaclite_open(struct net_device *dev)
920 {
921 	struct net_local *lp = netdev_priv(dev);
922 	int retval;
923 
924 	/* Just to be safe, stop the device first */
925 	xemaclite_disable_interrupts(lp);
926 
927 	if (lp->phy_node) {
928 		u32 bmcr;
929 
930 		lp->phy_dev = of_phy_connect(lp->ndev, lp->phy_node,
931 					     xemaclite_adjust_link, 0,
932 					     PHY_INTERFACE_MODE_MII);
933 		if (!lp->phy_dev) {
934 			dev_err(&lp->ndev->dev, "of_phy_connect() failed\n");
935 			return -ENODEV;
936 		}
937 
938 		/* EmacLite doesn't support giga-bit speeds */
939 		phy_set_max_speed(lp->phy_dev, SPEED_100);
940 
941 		/* Don't advertise 1000BASE-T Full/Half duplex speeds */
942 		phy_write(lp->phy_dev, MII_CTRL1000, 0);
943 
944 		/* Advertise only 10 and 100mbps full/half duplex speeds */
945 		phy_write(lp->phy_dev, MII_ADVERTISE, ADVERTISE_ALL |
946 			  ADVERTISE_CSMA);
947 
948 		/* Restart auto negotiation */
949 		bmcr = phy_read(lp->phy_dev, MII_BMCR);
950 		bmcr |= (BMCR_ANENABLE | BMCR_ANRESTART);
951 		phy_write(lp->phy_dev, MII_BMCR, bmcr);
952 
953 		phy_start(lp->phy_dev);
954 	}
955 
956 	/* Set the MAC address each time opened */
957 	xemaclite_update_address(lp, dev->dev_addr);
958 
959 	/* Grab the IRQ */
960 	retval = request_irq(dev->irq, xemaclite_interrupt, 0, dev->name, dev);
961 	if (retval) {
962 		dev_err(&lp->ndev->dev, "Could not allocate interrupt %d\n",
963 			dev->irq);
964 		if (lp->phy_dev)
965 			phy_disconnect(lp->phy_dev);
966 		lp->phy_dev = NULL;
967 
968 		return retval;
969 	}
970 
971 	/* Enable Interrupts */
972 	xemaclite_enable_interrupts(lp);
973 
974 	/* We're ready to go */
975 	netif_start_queue(dev);
976 
977 	return 0;
978 }
979 
980 /**
981  * xemaclite_close - Close the network device
982  * @dev:	Pointer to the network device
983  *
984  * This function stops the Tx queue, disables interrupts and frees the IRQ for
985  * the Emaclite device.
986  * It also disconnects the phy device associated with the Emaclite device.
987  *
988  * Return:	0, always.
989  */
990 static int xemaclite_close(struct net_device *dev)
991 {
992 	struct net_local *lp = netdev_priv(dev);
993 
994 	netif_stop_queue(dev);
995 	xemaclite_disable_interrupts(lp);
996 	free_irq(dev->irq, dev);
997 
998 	if (lp->phy_dev)
999 		phy_disconnect(lp->phy_dev);
1000 	lp->phy_dev = NULL;
1001 
1002 	return 0;
1003 }
1004 
1005 /**
1006  * xemaclite_send - Transmit a frame
1007  * @orig_skb:	Pointer to the socket buffer to be transmitted
1008  * @dev:	Pointer to the network device
1009  *
1010  * This function checks if the Tx buffer of the Emaclite device is free to send
1011  * data. If so, it fills the Tx buffer with data from socket buffer data,
1012  * updates the stats and frees the socket buffer. The Tx completion is signaled
1013  * by an interrupt. If the Tx buffer isn't free, then the socket buffer is
1014  * deferred and the Tx queue is stopped so that the deferred socket buffer can
1015  * be transmitted when the Emaclite device is free to transmit data.
1016  *
1017  * Return:	NETDEV_TX_OK, always.
1018  */
1019 static netdev_tx_t
1020 xemaclite_send(struct sk_buff *orig_skb, struct net_device *dev)
1021 {
1022 	struct net_local *lp = netdev_priv(dev);
1023 	struct sk_buff *new_skb;
1024 	unsigned int len;
1025 	unsigned long flags;
1026 
1027 	len = orig_skb->len;
1028 
1029 	new_skb = orig_skb;
1030 
1031 	spin_lock_irqsave(&lp->reset_lock, flags);
1032 	if (xemaclite_send_data(lp, (u8 *)new_skb->data, len) != 0) {
1033 		/* If the Emaclite Tx buffer is busy, stop the Tx queue and
1034 		 * defer the skb for transmission during the ISR, after the
1035 		 * current transmission is complete
1036 		 */
1037 		netif_stop_queue(dev);
1038 		lp->deferred_skb = new_skb;
1039 		/* Take the time stamp now, since we can't do this in an ISR. */
1040 		skb_tx_timestamp(new_skb);
1041 		spin_unlock_irqrestore(&lp->reset_lock, flags);
1042 		return NETDEV_TX_OK;
1043 	}
1044 	spin_unlock_irqrestore(&lp->reset_lock, flags);
1045 
1046 	skb_tx_timestamp(new_skb);
1047 
1048 	dev->stats.tx_bytes += len;
1049 	dev_consume_skb_any(new_skb);
1050 
1051 	return NETDEV_TX_OK;
1052 }
1053 
1054 /**
1055  * get_bool - Get a parameter from the OF device
1056  * @ofdev:	Pointer to OF device structure
1057  * @s:		Property to be retrieved
1058  *
1059  * This function looks for a property in the device node and returns the value
1060  * of the property if its found or 0 if the property is not found.
1061  *
1062  * Return:	Value of the parameter if the parameter is found, or 0 otherwise
1063  */
1064 static bool get_bool(struct platform_device *ofdev, const char *s)
1065 {
1066 	u32 *p = (u32 *)of_get_property(ofdev->dev.of_node, s, NULL);
1067 
1068 	if (!p) {
1069 		dev_warn(&ofdev->dev, "Parameter %s not found, defaulting to false\n", s);
1070 		return false;
1071 	}
1072 
1073 	return (bool)*p;
1074 }
1075 
1076 /**
1077  * xemaclite_ethtools_get_drvinfo - Get various Axi Emac Lite driver info
1078  * @ndev:       Pointer to net_device structure
1079  * @ed:         Pointer to ethtool_drvinfo structure
1080  *
1081  * This implements ethtool command for getting the driver information.
1082  * Issue "ethtool -i ethX" under linux prompt to execute this function.
1083  */
1084 static void xemaclite_ethtools_get_drvinfo(struct net_device *ndev,
1085 					   struct ethtool_drvinfo *ed)
1086 {
1087 	strlcpy(ed->driver, DRIVER_NAME, sizeof(ed->driver));
1088 }
1089 
1090 static const struct ethtool_ops xemaclite_ethtool_ops = {
1091 	.get_drvinfo    = xemaclite_ethtools_get_drvinfo,
1092 	.get_link       = ethtool_op_get_link,
1093 	.get_link_ksettings = phy_ethtool_get_link_ksettings,
1094 	.set_link_ksettings = phy_ethtool_set_link_ksettings,
1095 };
1096 
1097 static const struct net_device_ops xemaclite_netdev_ops;
1098 
1099 /**
1100  * xemaclite_of_probe - Probe method for the Emaclite device.
1101  * @ofdev:	Pointer to OF device structure
1102  *
1103  * This function probes for the Emaclite device in the device tree.
1104  * It initializes the driver data structure and the hardware, sets the MAC
1105  * address and registers the network device.
1106  * It also registers a mii_bus for the Emaclite device, if MDIO is included
1107  * in the device.
1108  *
1109  * Return:	0, if the driver is bound to the Emaclite device, or
1110  *		a negative error if there is failure.
1111  */
1112 static int xemaclite_of_probe(struct platform_device *ofdev)
1113 {
1114 	struct resource *res;
1115 	struct net_device *ndev = NULL;
1116 	struct net_local *lp = NULL;
1117 	struct device *dev = &ofdev->dev;
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 
1160 	rc = of_get_mac_address(ofdev->dev.of_node, ndev->dev_addr);
1161 	if (rc) {
1162 		dev_warn(dev, "No MAC address found, using random\n");
1163 		eth_hw_addr_random(ndev);
1164 	}
1165 
1166 	/* Clear the Tx CSR's in case this is a restart */
1167 	xemaclite_writel(0, lp->base_addr + XEL_TSR_OFFSET);
1168 	xemaclite_writel(0, lp->base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);
1169 
1170 	/* Set the MAC address in the EmacLite device */
1171 	xemaclite_update_address(lp, ndev->dev_addr);
1172 
1173 	lp->phy_node = of_parse_phandle(ofdev->dev.of_node, "phy-handle", 0);
1174 	xemaclite_mdio_setup(lp, &ofdev->dev);
1175 
1176 	dev_info(dev, "MAC address is now %pM\n", ndev->dev_addr);
1177 
1178 	ndev->netdev_ops = &xemaclite_netdev_ops;
1179 	ndev->ethtool_ops = &xemaclite_ethtool_ops;
1180 	ndev->flags &= ~IFF_MULTICAST;
1181 	ndev->watchdog_timeo = TX_TIMEOUT;
1182 
1183 	/* Finally, register the device */
1184 	rc = register_netdev(ndev);
1185 	if (rc) {
1186 		dev_err(dev,
1187 			"Cannot register network device, aborting\n");
1188 		goto error;
1189 	}
1190 
1191 	dev_info(dev,
1192 		 "Xilinx EmacLite at 0x%08lX mapped to 0x%08lX, irq=%d\n",
1193 		 (unsigned long __force)ndev->mem_start,
1194 		 (unsigned long __force)lp->base_addr, ndev->irq);
1195 	return 0;
1196 
1197 error:
1198 	free_netdev(ndev);
1199 	return rc;
1200 }
1201 
1202 /**
1203  * xemaclite_of_remove - Unbind the driver from the Emaclite device.
1204  * @of_dev:	Pointer to OF device structure
1205  *
1206  * This function is called if a device is physically removed from the system or
1207  * if the driver module is being unloaded. It frees any resources allocated to
1208  * the device.
1209  *
1210  * Return:	0, always.
1211  */
1212 static int xemaclite_of_remove(struct platform_device *of_dev)
1213 {
1214 	struct net_device *ndev = platform_get_drvdata(of_dev);
1215 
1216 	struct net_local *lp = netdev_priv(ndev);
1217 
1218 	/* Un-register the mii_bus, if configured */
1219 	if (lp->mii_bus) {
1220 		mdiobus_unregister(lp->mii_bus);
1221 		mdiobus_free(lp->mii_bus);
1222 		lp->mii_bus = NULL;
1223 	}
1224 
1225 	unregister_netdev(ndev);
1226 
1227 	of_node_put(lp->phy_node);
1228 	lp->phy_node = NULL;
1229 
1230 	free_netdev(ndev);
1231 
1232 	return 0;
1233 }
1234 
1235 #ifdef CONFIG_NET_POLL_CONTROLLER
1236 static void
1237 xemaclite_poll_controller(struct net_device *ndev)
1238 {
1239 	disable_irq(ndev->irq);
1240 	xemaclite_interrupt(ndev->irq, ndev);
1241 	enable_irq(ndev->irq);
1242 }
1243 #endif
1244 
1245 /* Ioctl MII Interface */
1246 static int xemaclite_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1247 {
1248 	if (!dev->phydev || !netif_running(dev))
1249 		return -EINVAL;
1250 
1251 	switch (cmd) {
1252 	case SIOCGMIIPHY:
1253 	case SIOCGMIIREG:
1254 	case SIOCSMIIREG:
1255 		return phy_mii_ioctl(dev->phydev, rq, cmd);
1256 	default:
1257 		return -EOPNOTSUPP;
1258 	}
1259 }
1260 
1261 static const struct net_device_ops xemaclite_netdev_ops = {
1262 	.ndo_open		= xemaclite_open,
1263 	.ndo_stop		= xemaclite_close,
1264 	.ndo_start_xmit		= xemaclite_send,
1265 	.ndo_set_mac_address	= xemaclite_set_mac_address,
1266 	.ndo_tx_timeout		= xemaclite_tx_timeout,
1267 	.ndo_do_ioctl		= xemaclite_ioctl,
1268 #ifdef CONFIG_NET_POLL_CONTROLLER
1269 	.ndo_poll_controller = xemaclite_poll_controller,
1270 #endif
1271 };
1272 
1273 /* Match table for OF platform binding */
1274 static const struct of_device_id xemaclite_of_match[] = {
1275 	{ .compatible = "xlnx,opb-ethernetlite-1.01.a", },
1276 	{ .compatible = "xlnx,opb-ethernetlite-1.01.b", },
1277 	{ .compatible = "xlnx,xps-ethernetlite-1.00.a", },
1278 	{ .compatible = "xlnx,xps-ethernetlite-2.00.a", },
1279 	{ .compatible = "xlnx,xps-ethernetlite-2.01.a", },
1280 	{ .compatible = "xlnx,xps-ethernetlite-3.00.a", },
1281 	{ /* end of list */ },
1282 };
1283 MODULE_DEVICE_TABLE(of, xemaclite_of_match);
1284 
1285 static struct platform_driver xemaclite_of_driver = {
1286 	.driver = {
1287 		.name = DRIVER_NAME,
1288 		.of_match_table = xemaclite_of_match,
1289 	},
1290 	.probe		= xemaclite_of_probe,
1291 	.remove		= xemaclite_of_remove,
1292 };
1293 
1294 module_platform_driver(xemaclite_of_driver);
1295 
1296 MODULE_AUTHOR("Xilinx, Inc.");
1297 MODULE_DESCRIPTION("Xilinx Ethernet MAC Lite driver");
1298 MODULE_LICENSE("GPL");
1299