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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  */
xemaclite_enable_interrupts(struct net_local * drvdata)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  */
xemaclite_disable_interrupts(struct net_local * drvdata)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  */
xemaclite_aligned_write(void * src_ptr,u32 * dest_ptr,unsigned length)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  */
xemaclite_aligned_read(u32 * src_ptr,u8 * dest_ptr,unsigned length)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  */
xemaclite_send_data(struct net_local * drvdata,u8 * data,unsigned int byte_count)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  */
xemaclite_recv_data(struct net_local * drvdata,u8 * data,int maxlen)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  */
xemaclite_update_address(struct net_local * drvdata,u8 * address_ptr)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  */
xemaclite_set_mac_address(struct net_device * dev,void * address)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  *
522  * This function is called when Tx time out occurs for Emaclite device.
523  */
xemaclite_tx_timeout(struct net_device * dev,unsigned int txqueue)524 static void xemaclite_tx_timeout(struct net_device *dev, unsigned int txqueue)
525 {
526 	struct net_local *lp = netdev_priv(dev);
527 	unsigned long flags;
528 
529 	dev_err(&lp->ndev->dev, "Exceeded transmit timeout of %lu ms\n",
530 		TX_TIMEOUT * 1000UL / HZ);
531 
532 	dev->stats.tx_errors++;
533 
534 	/* Reset the device */
535 	spin_lock_irqsave(&lp->reset_lock, flags);
536 
537 	/* Shouldn't really be necessary, but shouldn't hurt */
538 	netif_stop_queue(dev);
539 
540 	xemaclite_disable_interrupts(lp);
541 	xemaclite_enable_interrupts(lp);
542 
543 	if (lp->deferred_skb) {
544 		dev_kfree_skb(lp->deferred_skb);
545 		lp->deferred_skb = NULL;
546 		dev->stats.tx_errors++;
547 	}
548 
549 	/* To exclude tx timeout */
550 	netif_trans_update(dev); /* prevent tx timeout */
551 
552 	/* We're all ready to go. Start the queue */
553 	netif_wake_queue(dev);
554 	spin_unlock_irqrestore(&lp->reset_lock, flags);
555 }
556 
557 /**********************/
558 /* Interrupt Handlers */
559 /**********************/
560 
561 /**
562  * xemaclite_tx_handler - Interrupt handler for frames sent
563  * @dev:	Pointer to the network device
564  *
565  * This function updates the number of packets transmitted and handles the
566  * deferred skb, if there is one.
567  */
xemaclite_tx_handler(struct net_device * dev)568 static void xemaclite_tx_handler(struct net_device *dev)
569 {
570 	struct net_local *lp = netdev_priv(dev);
571 
572 	dev->stats.tx_packets++;
573 
574 	if (!lp->deferred_skb)
575 		return;
576 
577 	if (xemaclite_send_data(lp, (u8 *)lp->deferred_skb->data,
578 				lp->deferred_skb->len))
579 		return;
580 
581 	dev->stats.tx_bytes += lp->deferred_skb->len;
582 	dev_consume_skb_irq(lp->deferred_skb);
583 	lp->deferred_skb = NULL;
584 	netif_trans_update(dev); /* prevent tx timeout */
585 	netif_wake_queue(dev);
586 }
587 
588 /**
589  * xemaclite_rx_handler- Interrupt handler for frames received
590  * @dev:	Pointer to the network device
591  *
592  * This function allocates memory for a socket buffer, fills it with data
593  * received and hands it over to the TCP/IP stack.
594  */
xemaclite_rx_handler(struct net_device * dev)595 static void xemaclite_rx_handler(struct net_device *dev)
596 {
597 	struct net_local *lp = netdev_priv(dev);
598 	struct sk_buff *skb;
599 	unsigned int align;
600 	u32 len;
601 
602 	len = ETH_FRAME_LEN + ETH_FCS_LEN;
603 	skb = netdev_alloc_skb(dev, len + ALIGNMENT);
604 	if (!skb) {
605 		/* Couldn't get memory. */
606 		dev->stats.rx_dropped++;
607 		dev_err(&lp->ndev->dev, "Could not allocate receive buffer\n");
608 		return;
609 	}
610 
611 	/* A new skb should have the data halfword aligned, but this code is
612 	 * here just in case that isn't true. Calculate how many
613 	 * bytes we should reserve to get the data to start on a word
614 	 * boundary
615 	 */
616 	align = BUFFER_ALIGN(skb->data);
617 	if (align)
618 		skb_reserve(skb, align);
619 
620 	skb_reserve(skb, 2);
621 
622 	len = xemaclite_recv_data(lp, (u8 *)skb->data, len);
623 
624 	if (!len) {
625 		dev->stats.rx_errors++;
626 		dev_kfree_skb_irq(skb);
627 		return;
628 	}
629 
630 	skb_put(skb, len);	/* Tell the skb how much data we got */
631 
632 	skb->protocol = eth_type_trans(skb, dev);
633 	skb_checksum_none_assert(skb);
634 
635 	dev->stats.rx_packets++;
636 	dev->stats.rx_bytes += len;
637 
638 	if (!skb_defer_rx_timestamp(skb))
639 		netif_rx(skb);	/* Send the packet upstream */
640 }
641 
642 /**
643  * xemaclite_interrupt - Interrupt handler for this driver
644  * @irq:	Irq of the Emaclite device
645  * @dev_id:	Void pointer to the network device instance used as callback
646  *		reference
647  *
648  * Return:	IRQ_HANDLED
649  *
650  * This function handles the Tx and Rx interrupts of the EmacLite device.
651  */
xemaclite_interrupt(int irq,void * dev_id)652 static irqreturn_t xemaclite_interrupt(int irq, void *dev_id)
653 {
654 	bool tx_complete = false;
655 	struct net_device *dev = dev_id;
656 	struct net_local *lp = netdev_priv(dev);
657 	void __iomem *base_addr = lp->base_addr;
658 	u32 tx_status;
659 
660 	/* Check if there is Rx Data available */
661 	if ((xemaclite_readl(base_addr + XEL_RSR_OFFSET) &
662 			 XEL_RSR_RECV_DONE_MASK) ||
663 	    (xemaclite_readl(base_addr + XEL_BUFFER_OFFSET + XEL_RSR_OFFSET)
664 			 & XEL_RSR_RECV_DONE_MASK))
665 
666 		xemaclite_rx_handler(dev);
667 
668 	/* Check if the Transmission for the first buffer is completed */
669 	tx_status = xemaclite_readl(base_addr + XEL_TSR_OFFSET);
670 	if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
671 		(tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {
672 
673 		tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
674 		xemaclite_writel(tx_status, base_addr + XEL_TSR_OFFSET);
675 
676 		tx_complete = true;
677 	}
678 
679 	/* Check if the Transmission for the second buffer is completed */
680 	tx_status = xemaclite_readl(base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);
681 	if (((tx_status & XEL_TSR_XMIT_BUSY_MASK) == 0) &&
682 		(tx_status & XEL_TSR_XMIT_ACTIVE_MASK) != 0) {
683 
684 		tx_status &= ~XEL_TSR_XMIT_ACTIVE_MASK;
685 		xemaclite_writel(tx_status, base_addr + XEL_BUFFER_OFFSET +
686 				 XEL_TSR_OFFSET);
687 
688 		tx_complete = true;
689 	}
690 
691 	/* If there was a Tx interrupt, call the Tx Handler */
692 	if (tx_complete != 0)
693 		xemaclite_tx_handler(dev);
694 
695 	return IRQ_HANDLED;
696 }
697 
698 /**********************/
699 /* MDIO Bus functions */
700 /**********************/
701 
702 /**
703  * xemaclite_mdio_wait - Wait for the MDIO to be ready to use
704  * @lp:		Pointer to the Emaclite device private data
705  *
706  * This function waits till the device is ready to accept a new MDIO
707  * request.
708  *
709  * Return:	0 for success or ETIMEDOUT for a timeout
710  */
711 
xemaclite_mdio_wait(struct net_local * lp)712 static int xemaclite_mdio_wait(struct net_local *lp)
713 {
714 	u32 val;
715 
716 	/* wait for the MDIO interface to not be busy or timeout
717 	 * after some time.
718 	 */
719 	return readx_poll_timeout(xemaclite_readl,
720 				  lp->base_addr + XEL_MDIOCTRL_OFFSET,
721 				  val, !(val & XEL_MDIOCTRL_MDIOSTS_MASK),
722 				  1000, 20000);
723 }
724 
725 /**
726  * xemaclite_mdio_read - Read from a given MII management register
727  * @bus:	the mii_bus struct
728  * @phy_id:	the phy address
729  * @reg:	register number to read from
730  *
731  * This function waits till the device is ready to accept a new MDIO
732  * request and then writes the phy address to the MDIO Address register
733  * and reads data from MDIO Read Data register, when its available.
734  *
735  * Return:	Value read from the MII management register
736  */
xemaclite_mdio_read(struct mii_bus * bus,int phy_id,int reg)737 static int xemaclite_mdio_read(struct mii_bus *bus, int phy_id, int reg)
738 {
739 	struct net_local *lp = bus->priv;
740 	u32 ctrl_reg;
741 	u32 rc;
742 
743 	if (xemaclite_mdio_wait(lp))
744 		return -ETIMEDOUT;
745 
746 	/* Write the PHY address, register number and set the OP bit in the
747 	 * MDIO Address register. Set the Status bit in the MDIO Control
748 	 * register to start a MDIO read transaction.
749 	 */
750 	ctrl_reg = xemaclite_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
751 	xemaclite_writel(XEL_MDIOADDR_OP_MASK |
752 			 ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
753 			 lp->base_addr + XEL_MDIOADDR_OFFSET);
754 	xemaclite_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
755 			 lp->base_addr + XEL_MDIOCTRL_OFFSET);
756 
757 	if (xemaclite_mdio_wait(lp))
758 		return -ETIMEDOUT;
759 
760 	rc = xemaclite_readl(lp->base_addr + XEL_MDIORD_OFFSET);
761 
762 	dev_dbg(&lp->ndev->dev,
763 		"%s(phy_id=%i, reg=%x) == %x\n", __func__,
764 		phy_id, reg, rc);
765 
766 	return rc;
767 }
768 
769 /**
770  * xemaclite_mdio_write - Write to a given MII management register
771  * @bus:	the mii_bus struct
772  * @phy_id:	the phy address
773  * @reg:	register number to write to
774  * @val:	value to write to the register number specified by reg
775  *
776  * This function waits till the device is ready to accept a new MDIO
777  * request and then writes the val to the MDIO Write Data register.
778  *
779  * Return:      0 upon success or a negative error upon failure
780  */
xemaclite_mdio_write(struct mii_bus * bus,int phy_id,int reg,u16 val)781 static int xemaclite_mdio_write(struct mii_bus *bus, int phy_id, int reg,
782 				u16 val)
783 {
784 	struct net_local *lp = bus->priv;
785 	u32 ctrl_reg;
786 
787 	dev_dbg(&lp->ndev->dev,
788 		"%s(phy_id=%i, reg=%x, val=%x)\n", __func__,
789 		phy_id, reg, val);
790 
791 	if (xemaclite_mdio_wait(lp))
792 		return -ETIMEDOUT;
793 
794 	/* Write the PHY address, register number and clear the OP bit in the
795 	 * MDIO Address register and then write the value into the MDIO Write
796 	 * Data register. Finally, set the Status bit in the MDIO Control
797 	 * register to start a MDIO write transaction.
798 	 */
799 	ctrl_reg = xemaclite_readl(lp->base_addr + XEL_MDIOCTRL_OFFSET);
800 	xemaclite_writel(~XEL_MDIOADDR_OP_MASK &
801 			 ((phy_id << XEL_MDIOADDR_PHYADR_SHIFT) | reg),
802 			 lp->base_addr + XEL_MDIOADDR_OFFSET);
803 	xemaclite_writel(val, lp->base_addr + XEL_MDIOWR_OFFSET);
804 	xemaclite_writel(ctrl_reg | XEL_MDIOCTRL_MDIOSTS_MASK,
805 			 lp->base_addr + XEL_MDIOCTRL_OFFSET);
806 
807 	return 0;
808 }
809 
810 /**
811  * xemaclite_mdio_setup - Register mii_bus for the Emaclite device
812  * @lp:		Pointer to the Emaclite device private data
813  * @dev:	Pointer to OF device structure
814  *
815  * This function enables MDIO bus in the Emaclite device and registers a
816  * mii_bus.
817  *
818  * Return:	0 upon success or a negative error upon failure
819  */
xemaclite_mdio_setup(struct net_local * lp,struct device * dev)820 static int xemaclite_mdio_setup(struct net_local *lp, struct device *dev)
821 {
822 	struct mii_bus *bus;
823 	int rc;
824 	struct resource res;
825 	struct device_node *np = of_get_parent(lp->phy_node);
826 	struct device_node *npp;
827 
828 	/* Don't register the MDIO bus if the phy_node or its parent node
829 	 * can't be found.
830 	 */
831 	if (!np) {
832 		dev_err(dev, "Failed to register mdio bus.\n");
833 		return -ENODEV;
834 	}
835 	npp = of_get_parent(np);
836 
837 	of_address_to_resource(npp, 0, &res);
838 	if (lp->ndev->mem_start != res.start) {
839 		struct phy_device *phydev;
840 		phydev = of_phy_find_device(lp->phy_node);
841 		if (!phydev)
842 			dev_info(dev,
843 				 "MDIO of the phy is not registered yet\n");
844 		else
845 			put_device(&phydev->mdio.dev);
846 		return 0;
847 	}
848 
849 	/* Enable the MDIO bus by asserting the enable bit in MDIO Control
850 	 * register.
851 	 */
852 	xemaclite_writel(XEL_MDIOCTRL_MDIOEN_MASK,
853 			 lp->base_addr + XEL_MDIOCTRL_OFFSET);
854 
855 	bus = mdiobus_alloc();
856 	if (!bus) {
857 		dev_err(dev, "Failed to allocate mdiobus\n");
858 		return -ENOMEM;
859 	}
860 
861 	snprintf(bus->id, MII_BUS_ID_SIZE, "%.8llx",
862 		 (unsigned long long)res.start);
863 	bus->priv = lp;
864 	bus->name = "Xilinx Emaclite MDIO";
865 	bus->read = xemaclite_mdio_read;
866 	bus->write = xemaclite_mdio_write;
867 	bus->parent = dev;
868 
869 	rc = of_mdiobus_register(bus, np);
870 	if (rc) {
871 		dev_err(dev, "Failed to register mdio bus.\n");
872 		goto err_register;
873 	}
874 
875 	lp->mii_bus = bus;
876 
877 	return 0;
878 
879 err_register:
880 	mdiobus_free(bus);
881 	return rc;
882 }
883 
884 /**
885  * xemaclite_adjust_link - Link state callback for the Emaclite device
886  * @ndev: pointer to net_device struct
887  *
888  * There's nothing in the Emaclite device to be configured when the link
889  * state changes. We just print the status.
890  */
xemaclite_adjust_link(struct net_device * ndev)891 static void xemaclite_adjust_link(struct net_device *ndev)
892 {
893 	struct net_local *lp = netdev_priv(ndev);
894 	struct phy_device *phy = lp->phy_dev;
895 	int link_state;
896 
897 	/* hash together the state values to decide if something has changed */
898 	link_state = phy->speed | (phy->duplex << 1) | phy->link;
899 
900 	if (lp->last_link != link_state) {
901 		lp->last_link = link_state;
902 		phy_print_status(phy);
903 	}
904 }
905 
906 /**
907  * xemaclite_open - Open the network device
908  * @dev:	Pointer to the network device
909  *
910  * This function sets the MAC address, requests an IRQ and enables interrupts
911  * for the Emaclite device and starts the Tx queue.
912  * It also connects to the phy device, if MDIO is included in Emaclite device.
913  *
914  * Return:	0 on success. -ENODEV, if PHY cannot be connected.
915  *		Non-zero error value on failure.
916  */
xemaclite_open(struct net_device * dev)917 static int xemaclite_open(struct net_device *dev)
918 {
919 	struct net_local *lp = netdev_priv(dev);
920 	int retval;
921 
922 	/* Just to be safe, stop the device first */
923 	xemaclite_disable_interrupts(lp);
924 
925 	if (lp->phy_node) {
926 		u32 bmcr;
927 
928 		lp->phy_dev = of_phy_connect(lp->ndev, lp->phy_node,
929 					     xemaclite_adjust_link, 0,
930 					     PHY_INTERFACE_MODE_MII);
931 		if (!lp->phy_dev) {
932 			dev_err(&lp->ndev->dev, "of_phy_connect() failed\n");
933 			return -ENODEV;
934 		}
935 
936 		/* EmacLite doesn't support giga-bit speeds */
937 		phy_set_max_speed(lp->phy_dev, SPEED_100);
938 
939 		/* Don't advertise 1000BASE-T Full/Half duplex speeds */
940 		phy_write(lp->phy_dev, MII_CTRL1000, 0);
941 
942 		/* Advertise only 10 and 100mbps full/half duplex speeds */
943 		phy_write(lp->phy_dev, MII_ADVERTISE, ADVERTISE_ALL |
944 			  ADVERTISE_CSMA);
945 
946 		/* Restart auto negotiation */
947 		bmcr = phy_read(lp->phy_dev, MII_BMCR);
948 		bmcr |= (BMCR_ANENABLE | BMCR_ANRESTART);
949 		phy_write(lp->phy_dev, MII_BMCR, bmcr);
950 
951 		phy_start(lp->phy_dev);
952 	}
953 
954 	/* Set the MAC address each time opened */
955 	xemaclite_update_address(lp, dev->dev_addr);
956 
957 	/* Grab the IRQ */
958 	retval = request_irq(dev->irq, xemaclite_interrupt, 0, dev->name, dev);
959 	if (retval) {
960 		dev_err(&lp->ndev->dev, "Could not allocate interrupt %d\n",
961 			dev->irq);
962 		if (lp->phy_dev)
963 			phy_disconnect(lp->phy_dev);
964 		lp->phy_dev = NULL;
965 
966 		return retval;
967 	}
968 
969 	/* Enable Interrupts */
970 	xemaclite_enable_interrupts(lp);
971 
972 	/* We're ready to go */
973 	netif_start_queue(dev);
974 
975 	return 0;
976 }
977 
978 /**
979  * xemaclite_close - Close the network device
980  * @dev:	Pointer to the network device
981  *
982  * This function stops the Tx queue, disables interrupts and frees the IRQ for
983  * the Emaclite device.
984  * It also disconnects the phy device associated with the Emaclite device.
985  *
986  * Return:	0, always.
987  */
xemaclite_close(struct net_device * dev)988 static int xemaclite_close(struct net_device *dev)
989 {
990 	struct net_local *lp = netdev_priv(dev);
991 
992 	netif_stop_queue(dev);
993 	xemaclite_disable_interrupts(lp);
994 	free_irq(dev->irq, dev);
995 
996 	if (lp->phy_dev)
997 		phy_disconnect(lp->phy_dev);
998 	lp->phy_dev = NULL;
999 
1000 	return 0;
1001 }
1002 
1003 /**
1004  * xemaclite_send - Transmit a frame
1005  * @orig_skb:	Pointer to the socket buffer to be transmitted
1006  * @dev:	Pointer to the network device
1007  *
1008  * This function checks if the Tx buffer of the Emaclite device is free to send
1009  * data. If so, it fills the Tx buffer with data from socket buffer data,
1010  * updates the stats and frees the socket buffer. The Tx completion is signaled
1011  * by an interrupt. If the Tx buffer isn't free, then the socket buffer is
1012  * deferred and the Tx queue is stopped so that the deferred socket buffer can
1013  * be transmitted when the Emaclite device is free to transmit data.
1014  *
1015  * Return:	NETDEV_TX_OK, always.
1016  */
1017 static netdev_tx_t
xemaclite_send(struct sk_buff * orig_skb,struct net_device * dev)1018 xemaclite_send(struct sk_buff *orig_skb, struct net_device *dev)
1019 {
1020 	struct net_local *lp = netdev_priv(dev);
1021 	struct sk_buff *new_skb;
1022 	unsigned int len;
1023 	unsigned long flags;
1024 
1025 	len = orig_skb->len;
1026 
1027 	new_skb = orig_skb;
1028 
1029 	spin_lock_irqsave(&lp->reset_lock, flags);
1030 	if (xemaclite_send_data(lp, (u8 *)new_skb->data, len) != 0) {
1031 		/* If the Emaclite Tx buffer is busy, stop the Tx queue and
1032 		 * defer the skb for transmission during the ISR, after the
1033 		 * current transmission is complete
1034 		 */
1035 		netif_stop_queue(dev);
1036 		lp->deferred_skb = new_skb;
1037 		/* Take the time stamp now, since we can't do this in an ISR. */
1038 		skb_tx_timestamp(new_skb);
1039 		spin_unlock_irqrestore(&lp->reset_lock, flags);
1040 		return NETDEV_TX_OK;
1041 	}
1042 	spin_unlock_irqrestore(&lp->reset_lock, flags);
1043 
1044 	skb_tx_timestamp(new_skb);
1045 
1046 	dev->stats.tx_bytes += len;
1047 	dev_consume_skb_any(new_skb);
1048 
1049 	return NETDEV_TX_OK;
1050 }
1051 
1052 /**
1053  * get_bool - Get a parameter from the OF device
1054  * @ofdev:	Pointer to OF device structure
1055  * @s:		Property to be retrieved
1056  *
1057  * This function looks for a property in the device node and returns the value
1058  * of the property if its found or 0 if the property is not found.
1059  *
1060  * Return:	Value of the parameter if the parameter is found, or 0 otherwise
1061  */
get_bool(struct platform_device * ofdev,const char * s)1062 static bool get_bool(struct platform_device *ofdev, const char *s)
1063 {
1064 	u32 *p = (u32 *)of_get_property(ofdev->dev.of_node, s, NULL);
1065 
1066 	if (!p) {
1067 		dev_warn(&ofdev->dev, "Parameter %s not found, defaulting to false\n", s);
1068 		return false;
1069 	}
1070 
1071 	return (bool)*p;
1072 }
1073 
1074 /**
1075  * xemaclite_ethtools_get_drvinfo - Get various Axi Emac Lite driver info
1076  * @ndev:       Pointer to net_device structure
1077  * @ed:         Pointer to ethtool_drvinfo structure
1078  *
1079  * This implements ethtool command for getting the driver information.
1080  * Issue "ethtool -i ethX" under linux prompt to execute this function.
1081  */
xemaclite_ethtools_get_drvinfo(struct net_device * ndev,struct ethtool_drvinfo * ed)1082 static void xemaclite_ethtools_get_drvinfo(struct net_device *ndev,
1083 					   struct ethtool_drvinfo *ed)
1084 {
1085 	strlcpy(ed->driver, DRIVER_NAME, sizeof(ed->driver));
1086 }
1087 
1088 static const struct ethtool_ops xemaclite_ethtool_ops = {
1089 	.get_drvinfo    = xemaclite_ethtools_get_drvinfo,
1090 	.get_link       = ethtool_op_get_link,
1091 	.get_link_ksettings = phy_ethtool_get_link_ksettings,
1092 	.set_link_ksettings = phy_ethtool_set_link_ksettings,
1093 };
1094 
1095 static const struct net_device_ops xemaclite_netdev_ops;
1096 
1097 /**
1098  * xemaclite_of_probe - Probe method for the Emaclite device.
1099  * @ofdev:	Pointer to OF device structure
1100  *
1101  * This function probes for the Emaclite device in the device tree.
1102  * It initializes the driver data structure and the hardware, sets the MAC
1103  * address and registers the network device.
1104  * It also registers a mii_bus for the Emaclite device, if MDIO is included
1105  * in the device.
1106  *
1107  * Return:	0, if the driver is bound to the Emaclite device, or
1108  *		a negative error if there is failure.
1109  */
xemaclite_of_probe(struct platform_device * ofdev)1110 static int xemaclite_of_probe(struct platform_device *ofdev)
1111 {
1112 	struct resource *res;
1113 	struct net_device *ndev = NULL;
1114 	struct net_local *lp = NULL;
1115 	struct device *dev = &ofdev->dev;
1116 	const void *mac_address;
1117 
1118 	int rc = 0;
1119 
1120 	dev_info(dev, "Device Tree Probing\n");
1121 
1122 	/* Create an ethernet device instance */
1123 	ndev = alloc_etherdev(sizeof(struct net_local));
1124 	if (!ndev)
1125 		return -ENOMEM;
1126 
1127 	dev_set_drvdata(dev, ndev);
1128 	SET_NETDEV_DEV(ndev, &ofdev->dev);
1129 
1130 	lp = netdev_priv(ndev);
1131 	lp->ndev = ndev;
1132 
1133 	/* Get IRQ for the device */
1134 	res = platform_get_resource(ofdev, IORESOURCE_IRQ, 0);
1135 	if (!res) {
1136 		dev_err(dev, "no IRQ found\n");
1137 		rc = -ENXIO;
1138 		goto error;
1139 	}
1140 
1141 	ndev->irq = res->start;
1142 
1143 	res = platform_get_resource(ofdev, IORESOURCE_MEM, 0);
1144 	lp->base_addr = devm_ioremap_resource(&ofdev->dev, res);
1145 	if (IS_ERR(lp->base_addr)) {
1146 		rc = PTR_ERR(lp->base_addr);
1147 		goto error;
1148 	}
1149 
1150 	ndev->mem_start = res->start;
1151 	ndev->mem_end = res->end;
1152 
1153 	spin_lock_init(&lp->reset_lock);
1154 	lp->next_tx_buf_to_use = 0x0;
1155 	lp->next_rx_buf_to_use = 0x0;
1156 	lp->tx_ping_pong = get_bool(ofdev, "xlnx,tx-ping-pong");
1157 	lp->rx_ping_pong = get_bool(ofdev, "xlnx,rx-ping-pong");
1158 	mac_address = of_get_mac_address(ofdev->dev.of_node);
1159 
1160 	if (!IS_ERR(mac_address)) {
1161 		/* Set the MAC address. */
1162 		ether_addr_copy(ndev->dev_addr, mac_address);
1163 	} else {
1164 		dev_warn(dev, "No MAC address found, using random\n");
1165 		eth_hw_addr_random(ndev);
1166 	}
1167 
1168 	/* Clear the Tx CSR's in case this is a restart */
1169 	xemaclite_writel(0, lp->base_addr + XEL_TSR_OFFSET);
1170 	xemaclite_writel(0, lp->base_addr + XEL_BUFFER_OFFSET + XEL_TSR_OFFSET);
1171 
1172 	/* Set the MAC address in the EmacLite device */
1173 	xemaclite_update_address(lp, ndev->dev_addr);
1174 
1175 	lp->phy_node = of_parse_phandle(ofdev->dev.of_node, "phy-handle", 0);
1176 	xemaclite_mdio_setup(lp, &ofdev->dev);
1177 
1178 	dev_info(dev, "MAC address is now %pM\n", ndev->dev_addr);
1179 
1180 	ndev->netdev_ops = &xemaclite_netdev_ops;
1181 	ndev->ethtool_ops = &xemaclite_ethtool_ops;
1182 	ndev->flags &= ~IFF_MULTICAST;
1183 	ndev->watchdog_timeo = TX_TIMEOUT;
1184 
1185 	/* Finally, register the device */
1186 	rc = register_netdev(ndev);
1187 	if (rc) {
1188 		dev_err(dev,
1189 			"Cannot register network device, aborting\n");
1190 		goto error;
1191 	}
1192 
1193 	dev_info(dev,
1194 		 "Xilinx EmacLite at 0x%08X mapped to 0x%p, irq=%d\n",
1195 		 (unsigned int __force)ndev->mem_start, lp->base_addr, ndev->irq);
1196 	return 0;
1197 
1198 error:
1199 	free_netdev(ndev);
1200 	return rc;
1201 }
1202 
1203 /**
1204  * xemaclite_of_remove - Unbind the driver from the Emaclite device.
1205  * @of_dev:	Pointer to OF device structure
1206  *
1207  * This function is called if a device is physically removed from the system or
1208  * if the driver module is being unloaded. It frees any resources allocated to
1209  * the device.
1210  *
1211  * Return:	0, always.
1212  */
xemaclite_of_remove(struct platform_device * of_dev)1213 static int xemaclite_of_remove(struct platform_device *of_dev)
1214 {
1215 	struct net_device *ndev = platform_get_drvdata(of_dev);
1216 
1217 	struct net_local *lp = netdev_priv(ndev);
1218 
1219 	/* Un-register the mii_bus, if configured */
1220 	if (lp->mii_bus) {
1221 		mdiobus_unregister(lp->mii_bus);
1222 		mdiobus_free(lp->mii_bus);
1223 		lp->mii_bus = NULL;
1224 	}
1225 
1226 	unregister_netdev(ndev);
1227 
1228 	of_node_put(lp->phy_node);
1229 	lp->phy_node = NULL;
1230 
1231 	free_netdev(ndev);
1232 
1233 	return 0;
1234 }
1235 
1236 #ifdef CONFIG_NET_POLL_CONTROLLER
1237 static void
xemaclite_poll_controller(struct net_device * ndev)1238 xemaclite_poll_controller(struct net_device *ndev)
1239 {
1240 	disable_irq(ndev->irq);
1241 	xemaclite_interrupt(ndev->irq, ndev);
1242 	enable_irq(ndev->irq);
1243 }
1244 #endif
1245 
1246 /* Ioctl MII Interface */
xemaclite_ioctl(struct net_device * dev,struct ifreq * rq,int cmd)1247 static int xemaclite_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
1248 {
1249 	if (!dev->phydev || !netif_running(dev))
1250 		return -EINVAL;
1251 
1252 	switch (cmd) {
1253 	case SIOCGMIIPHY:
1254 	case SIOCGMIIREG:
1255 	case SIOCSMIIREG:
1256 		return phy_mii_ioctl(dev->phydev, rq, cmd);
1257 	default:
1258 		return -EOPNOTSUPP;
1259 	}
1260 }
1261 
1262 static const struct net_device_ops xemaclite_netdev_ops = {
1263 	.ndo_open		= xemaclite_open,
1264 	.ndo_stop		= xemaclite_close,
1265 	.ndo_start_xmit		= xemaclite_send,
1266 	.ndo_set_mac_address	= xemaclite_set_mac_address,
1267 	.ndo_tx_timeout		= xemaclite_tx_timeout,
1268 	.ndo_do_ioctl		= xemaclite_ioctl,
1269 #ifdef CONFIG_NET_POLL_CONTROLLER
1270 	.ndo_poll_controller = xemaclite_poll_controller,
1271 #endif
1272 };
1273 
1274 /* Match table for OF platform binding */
1275 static const struct of_device_id xemaclite_of_match[] = {
1276 	{ .compatible = "xlnx,opb-ethernetlite-1.01.a", },
1277 	{ .compatible = "xlnx,opb-ethernetlite-1.01.b", },
1278 	{ .compatible = "xlnx,xps-ethernetlite-1.00.a", },
1279 	{ .compatible = "xlnx,xps-ethernetlite-2.00.a", },
1280 	{ .compatible = "xlnx,xps-ethernetlite-2.01.a", },
1281 	{ .compatible = "xlnx,xps-ethernetlite-3.00.a", },
1282 	{ /* end of list */ },
1283 };
1284 MODULE_DEVICE_TABLE(of, xemaclite_of_match);
1285 
1286 static struct platform_driver xemaclite_of_driver = {
1287 	.driver = {
1288 		.name = DRIVER_NAME,
1289 		.of_match_table = xemaclite_of_match,
1290 	},
1291 	.probe		= xemaclite_of_probe,
1292 	.remove		= xemaclite_of_remove,
1293 };
1294 
1295 module_platform_driver(xemaclite_of_driver);
1296 
1297 MODULE_AUTHOR("Xilinx, Inc.");
1298 MODULE_DESCRIPTION("Xilinx Ethernet MAC Lite driver");
1299 MODULE_LICENSE("GPL");
1300