1 /*
2  * Aeroflex Gaisler GRETH 10/100/1G Ethernet MAC.
3  *
4  * 2005-2010 (c) Aeroflex Gaisler AB
5  *
6  * This driver supports GRETH 10/100 and GRETH 10/100/1G Ethernet MACs
7  * available in the GRLIB VHDL IP core library.
8  *
9  * Full documentation of both cores can be found here:
10  * http://www.gaisler.com/products/grlib/grip.pdf
11  *
12  * The Gigabit version supports scatter/gather DMA, any alignment of
13  * buffers and checksum offloading.
14  *
15  * This program is free software; you can redistribute it and/or modify it
16  * under the terms of the GNU General Public License as published by the
17  * Free Software Foundation; either version 2 of the License, or (at your
18  * option) any later version.
19  *
20  * Contributors: Kristoffer Glembo
21  *               Daniel Hellstrom
22  *               Marko Isomaki
23  */
24 
25 #include <linux/dma-mapping.h>
26 #include <linux/module.h>
27 #include <linux/uaccess.h>
28 #include <linux/interrupt.h>
29 #include <linux/netdevice.h>
30 #include <linux/etherdevice.h>
31 #include <linux/ethtool.h>
32 #include <linux/skbuff.h>
33 #include <linux/io.h>
34 #include <linux/crc32.h>
35 #include <linux/mii.h>
36 #include <linux/of_device.h>
37 #include <linux/of_net.h>
38 #include <linux/of_platform.h>
39 #include <linux/slab.h>
40 #include <asm/cacheflush.h>
41 #include <asm/byteorder.h>
42 
43 #ifdef CONFIG_SPARC
44 #include <asm/idprom.h>
45 #endif
46 
47 #include "greth.h"
48 
49 #define GRETH_DEF_MSG_ENABLE	  \
50 	(NETIF_MSG_DRV		| \
51 	 NETIF_MSG_PROBE	| \
52 	 NETIF_MSG_LINK		| \
53 	 NETIF_MSG_IFDOWN	| \
54 	 NETIF_MSG_IFUP		| \
55 	 NETIF_MSG_RX_ERR	| \
56 	 NETIF_MSG_TX_ERR)
57 
58 static int greth_debug = -1;	/* -1 == use GRETH_DEF_MSG_ENABLE as value */
59 module_param(greth_debug, int, 0);
60 MODULE_PARM_DESC(greth_debug, "GRETH bitmapped debugging message enable value");
61 
62 /* Accept MAC address of the form macaddr=0x08,0x00,0x20,0x30,0x40,0x50 */
63 static int macaddr[6];
64 module_param_array(macaddr, int, NULL, 0);
65 MODULE_PARM_DESC(macaddr, "GRETH Ethernet MAC address");
66 
67 static int greth_edcl = 1;
68 module_param(greth_edcl, int, 0);
69 MODULE_PARM_DESC(greth_edcl, "GRETH EDCL usage indicator. Set to 1 if EDCL is used.");
70 
71 static int greth_open(struct net_device *dev);
72 static netdev_tx_t greth_start_xmit(struct sk_buff *skb,
73 	   struct net_device *dev);
74 static netdev_tx_t greth_start_xmit_gbit(struct sk_buff *skb,
75 	   struct net_device *dev);
76 static int greth_rx(struct net_device *dev, int limit);
77 static int greth_rx_gbit(struct net_device *dev, int limit);
78 static void greth_clean_tx(struct net_device *dev);
79 static void greth_clean_tx_gbit(struct net_device *dev);
80 static irqreturn_t greth_interrupt(int irq, void *dev_id);
81 static int greth_close(struct net_device *dev);
82 static int greth_set_mac_add(struct net_device *dev, void *p);
83 static void greth_set_multicast_list(struct net_device *dev);
84 
85 #define GRETH_REGLOAD(a)	    (be32_to_cpu(__raw_readl(&(a))))
86 #define GRETH_REGSAVE(a, v)         (__raw_writel(cpu_to_be32(v), &(a)))
87 #define GRETH_REGORIN(a, v)         (GRETH_REGSAVE(a, (GRETH_REGLOAD(a) | (v))))
88 #define GRETH_REGANDIN(a, v)        (GRETH_REGSAVE(a, (GRETH_REGLOAD(a) & (v))))
89 
90 #define NEXT_TX(N)      (((N) + 1) & GRETH_TXBD_NUM_MASK)
91 #define SKIP_TX(N, C)   (((N) + C) & GRETH_TXBD_NUM_MASK)
92 #define NEXT_RX(N)      (((N) + 1) & GRETH_RXBD_NUM_MASK)
93 
94 static void greth_print_rx_packet(void *addr, int len)
95 {
96 	print_hex_dump(KERN_DEBUG, "RX: ", DUMP_PREFIX_OFFSET, 16, 1,
97 			addr, len, true);
98 }
99 
100 static void greth_print_tx_packet(struct sk_buff *skb)
101 {
102 	int i;
103 	int length;
104 
105 	if (skb_shinfo(skb)->nr_frags == 0)
106 		length = skb->len;
107 	else
108 		length = skb_headlen(skb);
109 
110 	print_hex_dump(KERN_DEBUG, "TX: ", DUMP_PREFIX_OFFSET, 16, 1,
111 			skb->data, length, true);
112 
113 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
114 
115 		print_hex_dump(KERN_DEBUG, "TX: ", DUMP_PREFIX_OFFSET, 16, 1,
116 			       skb_frag_address(&skb_shinfo(skb)->frags[i]),
117 			       skb_shinfo(skb)->frags[i].size, true);
118 	}
119 }
120 
121 static inline void greth_enable_tx(struct greth_private *greth)
122 {
123 	wmb();
124 	GRETH_REGORIN(greth->regs->control, GRETH_TXEN);
125 }
126 
127 static inline void greth_enable_tx_and_irq(struct greth_private *greth)
128 {
129 	wmb(); /* BDs must been written to memory before enabling TX */
130 	GRETH_REGORIN(greth->regs->control, GRETH_TXEN | GRETH_TXI);
131 }
132 
133 static inline void greth_disable_tx(struct greth_private *greth)
134 {
135 	GRETH_REGANDIN(greth->regs->control, ~GRETH_TXEN);
136 }
137 
138 static inline void greth_enable_rx(struct greth_private *greth)
139 {
140 	wmb();
141 	GRETH_REGORIN(greth->regs->control, GRETH_RXEN);
142 }
143 
144 static inline void greth_disable_rx(struct greth_private *greth)
145 {
146 	GRETH_REGANDIN(greth->regs->control, ~GRETH_RXEN);
147 }
148 
149 static inline void greth_enable_irqs(struct greth_private *greth)
150 {
151 	GRETH_REGORIN(greth->regs->control, GRETH_RXI | GRETH_TXI);
152 }
153 
154 static inline void greth_disable_irqs(struct greth_private *greth)
155 {
156 	GRETH_REGANDIN(greth->regs->control, ~(GRETH_RXI|GRETH_TXI));
157 }
158 
159 static inline void greth_write_bd(u32 *bd, u32 val)
160 {
161 	__raw_writel(cpu_to_be32(val), bd);
162 }
163 
164 static inline u32 greth_read_bd(u32 *bd)
165 {
166 	return be32_to_cpu(__raw_readl(bd));
167 }
168 
169 static void greth_clean_rings(struct greth_private *greth)
170 {
171 	int i;
172 	struct greth_bd *rx_bdp = greth->rx_bd_base;
173 	struct greth_bd *tx_bdp = greth->tx_bd_base;
174 
175 	if (greth->gbit_mac) {
176 
177 		/* Free and unmap RX buffers */
178 		for (i = 0; i < GRETH_RXBD_NUM; i++, rx_bdp++) {
179 			if (greth->rx_skbuff[i] != NULL) {
180 				dev_kfree_skb(greth->rx_skbuff[i]);
181 				dma_unmap_single(greth->dev,
182 						 greth_read_bd(&rx_bdp->addr),
183 						 MAX_FRAME_SIZE+NET_IP_ALIGN,
184 						 DMA_FROM_DEVICE);
185 			}
186 		}
187 
188 		/* TX buffers */
189 		while (greth->tx_free < GRETH_TXBD_NUM) {
190 
191 			struct sk_buff *skb = greth->tx_skbuff[greth->tx_last];
192 			int nr_frags = skb_shinfo(skb)->nr_frags;
193 			tx_bdp = greth->tx_bd_base + greth->tx_last;
194 			greth->tx_last = NEXT_TX(greth->tx_last);
195 
196 			dma_unmap_single(greth->dev,
197 					 greth_read_bd(&tx_bdp->addr),
198 					 skb_headlen(skb),
199 					 DMA_TO_DEVICE);
200 
201 			for (i = 0; i < nr_frags; i++) {
202 				skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
203 				tx_bdp = greth->tx_bd_base + greth->tx_last;
204 
205 				dma_unmap_page(greth->dev,
206 					       greth_read_bd(&tx_bdp->addr),
207 					       skb_frag_size(frag),
208 					       DMA_TO_DEVICE);
209 
210 				greth->tx_last = NEXT_TX(greth->tx_last);
211 			}
212 			greth->tx_free += nr_frags+1;
213 			dev_kfree_skb(skb);
214 		}
215 
216 
217 	} else { /* 10/100 Mbps MAC */
218 
219 		for (i = 0; i < GRETH_RXBD_NUM; i++, rx_bdp++) {
220 			kfree(greth->rx_bufs[i]);
221 			dma_unmap_single(greth->dev,
222 					 greth_read_bd(&rx_bdp->addr),
223 					 MAX_FRAME_SIZE,
224 					 DMA_FROM_DEVICE);
225 		}
226 		for (i = 0; i < GRETH_TXBD_NUM; i++, tx_bdp++) {
227 			kfree(greth->tx_bufs[i]);
228 			dma_unmap_single(greth->dev,
229 					 greth_read_bd(&tx_bdp->addr),
230 					 MAX_FRAME_SIZE,
231 					 DMA_TO_DEVICE);
232 		}
233 	}
234 }
235 
236 static int greth_init_rings(struct greth_private *greth)
237 {
238 	struct sk_buff *skb;
239 	struct greth_bd *rx_bd, *tx_bd;
240 	u32 dma_addr;
241 	int i;
242 
243 	rx_bd = greth->rx_bd_base;
244 	tx_bd = greth->tx_bd_base;
245 
246 	/* Initialize descriptor rings and buffers */
247 	if (greth->gbit_mac) {
248 
249 		for (i = 0; i < GRETH_RXBD_NUM; i++) {
250 			skb = netdev_alloc_skb(greth->netdev, MAX_FRAME_SIZE+NET_IP_ALIGN);
251 			if (skb == NULL) {
252 				if (netif_msg_ifup(greth))
253 					dev_err(greth->dev, "Error allocating DMA ring.\n");
254 				goto cleanup;
255 			}
256 			skb_reserve(skb, NET_IP_ALIGN);
257 			dma_addr = dma_map_single(greth->dev,
258 						  skb->data,
259 						  MAX_FRAME_SIZE+NET_IP_ALIGN,
260 						  DMA_FROM_DEVICE);
261 
262 			if (dma_mapping_error(greth->dev, dma_addr)) {
263 				if (netif_msg_ifup(greth))
264 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
265 				goto cleanup;
266 			}
267 			greth->rx_skbuff[i] = skb;
268 			greth_write_bd(&rx_bd[i].addr, dma_addr);
269 			greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
270 		}
271 
272 	} else {
273 
274 		/* 10/100 MAC uses a fixed set of buffers and copy to/from SKBs */
275 		for (i = 0; i < GRETH_RXBD_NUM; i++) {
276 
277 			greth->rx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);
278 
279 			if (greth->rx_bufs[i] == NULL) {
280 				if (netif_msg_ifup(greth))
281 					dev_err(greth->dev, "Error allocating DMA ring.\n");
282 				goto cleanup;
283 			}
284 
285 			dma_addr = dma_map_single(greth->dev,
286 						  greth->rx_bufs[i],
287 						  MAX_FRAME_SIZE,
288 						  DMA_FROM_DEVICE);
289 
290 			if (dma_mapping_error(greth->dev, dma_addr)) {
291 				if (netif_msg_ifup(greth))
292 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
293 				goto cleanup;
294 			}
295 			greth_write_bd(&rx_bd[i].addr, dma_addr);
296 			greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
297 		}
298 		for (i = 0; i < GRETH_TXBD_NUM; i++) {
299 
300 			greth->tx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);
301 
302 			if (greth->tx_bufs[i] == NULL) {
303 				if (netif_msg_ifup(greth))
304 					dev_err(greth->dev, "Error allocating DMA ring.\n");
305 				goto cleanup;
306 			}
307 
308 			dma_addr = dma_map_single(greth->dev,
309 						  greth->tx_bufs[i],
310 						  MAX_FRAME_SIZE,
311 						  DMA_TO_DEVICE);
312 
313 			if (dma_mapping_error(greth->dev, dma_addr)) {
314 				if (netif_msg_ifup(greth))
315 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
316 				goto cleanup;
317 			}
318 			greth_write_bd(&tx_bd[i].addr, dma_addr);
319 			greth_write_bd(&tx_bd[i].stat, 0);
320 		}
321 	}
322 	greth_write_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat,
323 		       greth_read_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat) | GRETH_BD_WR);
324 
325 	/* Initialize pointers. */
326 	greth->rx_cur = 0;
327 	greth->tx_next = 0;
328 	greth->tx_last = 0;
329 	greth->tx_free = GRETH_TXBD_NUM;
330 
331 	/* Initialize descriptor base address */
332 	GRETH_REGSAVE(greth->regs->tx_desc_p, greth->tx_bd_base_phys);
333 	GRETH_REGSAVE(greth->regs->rx_desc_p, greth->rx_bd_base_phys);
334 
335 	return 0;
336 
337 cleanup:
338 	greth_clean_rings(greth);
339 	return -ENOMEM;
340 }
341 
342 static int greth_open(struct net_device *dev)
343 {
344 	struct greth_private *greth = netdev_priv(dev);
345 	int err;
346 
347 	err = greth_init_rings(greth);
348 	if (err) {
349 		if (netif_msg_ifup(greth))
350 			dev_err(&dev->dev, "Could not allocate memory for DMA rings\n");
351 		return err;
352 	}
353 
354 	err = request_irq(greth->irq, greth_interrupt, 0, "eth", (void *) dev);
355 	if (err) {
356 		if (netif_msg_ifup(greth))
357 			dev_err(&dev->dev, "Could not allocate interrupt %d\n", dev->irq);
358 		greth_clean_rings(greth);
359 		return err;
360 	}
361 
362 	if (netif_msg_ifup(greth))
363 		dev_dbg(&dev->dev, " starting queue\n");
364 	netif_start_queue(dev);
365 
366 	GRETH_REGSAVE(greth->regs->status, 0xFF);
367 
368 	napi_enable(&greth->napi);
369 
370 	greth_enable_irqs(greth);
371 	greth_enable_tx(greth);
372 	greth_enable_rx(greth);
373 	return 0;
374 
375 }
376 
377 static int greth_close(struct net_device *dev)
378 {
379 	struct greth_private *greth = netdev_priv(dev);
380 
381 	napi_disable(&greth->napi);
382 
383 	greth_disable_irqs(greth);
384 	greth_disable_tx(greth);
385 	greth_disable_rx(greth);
386 
387 	netif_stop_queue(dev);
388 
389 	free_irq(greth->irq, (void *) dev);
390 
391 	greth_clean_rings(greth);
392 
393 	return 0;
394 }
395 
396 static netdev_tx_t
397 greth_start_xmit(struct sk_buff *skb, struct net_device *dev)
398 {
399 	struct greth_private *greth = netdev_priv(dev);
400 	struct greth_bd *bdp;
401 	int err = NETDEV_TX_OK;
402 	u32 status, dma_addr, ctrl;
403 	unsigned long flags;
404 
405 	/* Clean TX Ring */
406 	greth_clean_tx(greth->netdev);
407 
408 	if (unlikely(greth->tx_free <= 0)) {
409 		spin_lock_irqsave(&greth->devlock, flags);/*save from poll/irq*/
410 		ctrl = GRETH_REGLOAD(greth->regs->control);
411 		/* Enable TX IRQ only if not already in poll() routine */
412 		if (ctrl & GRETH_RXI)
413 			GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_TXI);
414 		netif_stop_queue(dev);
415 		spin_unlock_irqrestore(&greth->devlock, flags);
416 		return NETDEV_TX_BUSY;
417 	}
418 
419 	if (netif_msg_pktdata(greth))
420 		greth_print_tx_packet(skb);
421 
422 
423 	if (unlikely(skb->len > MAX_FRAME_SIZE)) {
424 		dev->stats.tx_errors++;
425 		goto out;
426 	}
427 
428 	bdp = greth->tx_bd_base + greth->tx_next;
429 	dma_addr = greth_read_bd(&bdp->addr);
430 
431 	memcpy((unsigned char *) phys_to_virt(dma_addr), skb->data, skb->len);
432 
433 	dma_sync_single_for_device(greth->dev, dma_addr, skb->len, DMA_TO_DEVICE);
434 
435 	status = GRETH_BD_EN | GRETH_BD_IE | (skb->len & GRETH_BD_LEN);
436 	greth->tx_bufs_length[greth->tx_next] = skb->len & GRETH_BD_LEN;
437 
438 	/* Wrap around descriptor ring */
439 	if (greth->tx_next == GRETH_TXBD_NUM_MASK) {
440 		status |= GRETH_BD_WR;
441 	}
442 
443 	greth->tx_next = NEXT_TX(greth->tx_next);
444 	greth->tx_free--;
445 
446 	/* Write descriptor control word and enable transmission */
447 	greth_write_bd(&bdp->stat, status);
448 	spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
449 	greth_enable_tx(greth);
450 	spin_unlock_irqrestore(&greth->devlock, flags);
451 
452 out:
453 	dev_kfree_skb(skb);
454 	return err;
455 }
456 
457 static inline u16 greth_num_free_bds(u16 tx_last, u16 tx_next)
458 {
459 	if (tx_next < tx_last)
460 		return (tx_last - tx_next) - 1;
461 	else
462 		return GRETH_TXBD_NUM - (tx_next - tx_last) - 1;
463 }
464 
465 static netdev_tx_t
466 greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
467 {
468 	struct greth_private *greth = netdev_priv(dev);
469 	struct greth_bd *bdp;
470 	u32 status, dma_addr;
471 	int curr_tx, nr_frags, i, err = NETDEV_TX_OK;
472 	unsigned long flags;
473 	u16 tx_last;
474 
475 	nr_frags = skb_shinfo(skb)->nr_frags;
476 	tx_last = greth->tx_last;
477 	rmb(); /* tx_last is updated by the poll task */
478 
479 	if (greth_num_free_bds(tx_last, greth->tx_next) < nr_frags + 1) {
480 		netif_stop_queue(dev);
481 		err = NETDEV_TX_BUSY;
482 		goto out;
483 	}
484 
485 	if (netif_msg_pktdata(greth))
486 		greth_print_tx_packet(skb);
487 
488 	if (unlikely(skb->len > MAX_FRAME_SIZE)) {
489 		dev->stats.tx_errors++;
490 		goto out;
491 	}
492 
493 	/* Save skb pointer. */
494 	greth->tx_skbuff[greth->tx_next] = skb;
495 
496 	/* Linear buf */
497 	if (nr_frags != 0)
498 		status = GRETH_TXBD_MORE;
499 	else
500 		status = GRETH_BD_IE;
501 
502 	if (skb->ip_summed == CHECKSUM_PARTIAL)
503 		status |= GRETH_TXBD_CSALL;
504 	status |= skb_headlen(skb) & GRETH_BD_LEN;
505 	if (greth->tx_next == GRETH_TXBD_NUM_MASK)
506 		status |= GRETH_BD_WR;
507 
508 
509 	bdp = greth->tx_bd_base + greth->tx_next;
510 	greth_write_bd(&bdp->stat, status);
511 	dma_addr = dma_map_single(greth->dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
512 
513 	if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
514 		goto map_error;
515 
516 	greth_write_bd(&bdp->addr, dma_addr);
517 
518 	curr_tx = NEXT_TX(greth->tx_next);
519 
520 	/* Frags */
521 	for (i = 0; i < nr_frags; i++) {
522 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
523 		greth->tx_skbuff[curr_tx] = NULL;
524 		bdp = greth->tx_bd_base + curr_tx;
525 
526 		status = GRETH_BD_EN;
527 		if (skb->ip_summed == CHECKSUM_PARTIAL)
528 			status |= GRETH_TXBD_CSALL;
529 		status |= skb_frag_size(frag) & GRETH_BD_LEN;
530 
531 		/* Wrap around descriptor ring */
532 		if (curr_tx == GRETH_TXBD_NUM_MASK)
533 			status |= GRETH_BD_WR;
534 
535 		/* More fragments left */
536 		if (i < nr_frags - 1)
537 			status |= GRETH_TXBD_MORE;
538 		else
539 			status |= GRETH_BD_IE; /* enable IRQ on last fragment */
540 
541 		greth_write_bd(&bdp->stat, status);
542 
543 		dma_addr = skb_frag_dma_map(greth->dev, frag, 0, skb_frag_size(frag),
544 					    DMA_TO_DEVICE);
545 
546 		if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
547 			goto frag_map_error;
548 
549 		greth_write_bd(&bdp->addr, dma_addr);
550 
551 		curr_tx = NEXT_TX(curr_tx);
552 	}
553 
554 	wmb();
555 
556 	/* Enable the descriptor chain by enabling the first descriptor */
557 	bdp = greth->tx_bd_base + greth->tx_next;
558 	greth_write_bd(&bdp->stat,
559 		       greth_read_bd(&bdp->stat) | GRETH_BD_EN);
560 
561 	spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
562 	greth->tx_next = curr_tx;
563 	greth_enable_tx_and_irq(greth);
564 	spin_unlock_irqrestore(&greth->devlock, flags);
565 
566 	return NETDEV_TX_OK;
567 
568 frag_map_error:
569 	/* Unmap SKB mappings that succeeded and disable descriptor */
570 	for (i = 0; greth->tx_next + i != curr_tx; i++) {
571 		bdp = greth->tx_bd_base + greth->tx_next + i;
572 		dma_unmap_single(greth->dev,
573 				 greth_read_bd(&bdp->addr),
574 				 greth_read_bd(&bdp->stat) & GRETH_BD_LEN,
575 				 DMA_TO_DEVICE);
576 		greth_write_bd(&bdp->stat, 0);
577 	}
578 map_error:
579 	if (net_ratelimit())
580 		dev_warn(greth->dev, "Could not create TX DMA mapping\n");
581 	dev_kfree_skb(skb);
582 out:
583 	return err;
584 }
585 
586 static irqreturn_t greth_interrupt(int irq, void *dev_id)
587 {
588 	struct net_device *dev = dev_id;
589 	struct greth_private *greth;
590 	u32 status, ctrl;
591 	irqreturn_t retval = IRQ_NONE;
592 
593 	greth = netdev_priv(dev);
594 
595 	spin_lock(&greth->devlock);
596 
597 	/* Get the interrupt events that caused us to be here. */
598 	status = GRETH_REGLOAD(greth->regs->status);
599 
600 	/* Must see if interrupts are enabled also, INT_TX|INT_RX flags may be
601 	 * set regardless of whether IRQ is enabled or not. Especially
602 	 * important when shared IRQ.
603 	 */
604 	ctrl = GRETH_REGLOAD(greth->regs->control);
605 
606 	/* Handle rx and tx interrupts through poll */
607 	if (((status & (GRETH_INT_RE | GRETH_INT_RX)) && (ctrl & GRETH_RXI)) ||
608 	    ((status & (GRETH_INT_TE | GRETH_INT_TX)) && (ctrl & GRETH_TXI))) {
609 		retval = IRQ_HANDLED;
610 
611 		/* Disable interrupts and schedule poll() */
612 		greth_disable_irqs(greth);
613 		napi_schedule(&greth->napi);
614 	}
615 
616 	spin_unlock(&greth->devlock);
617 
618 	return retval;
619 }
620 
621 static void greth_clean_tx(struct net_device *dev)
622 {
623 	struct greth_private *greth;
624 	struct greth_bd *bdp;
625 	u32 stat;
626 
627 	greth = netdev_priv(dev);
628 
629 	while (1) {
630 		bdp = greth->tx_bd_base + greth->tx_last;
631 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
632 		mb();
633 		stat = greth_read_bd(&bdp->stat);
634 
635 		if (unlikely(stat & GRETH_BD_EN))
636 			break;
637 
638 		if (greth->tx_free == GRETH_TXBD_NUM)
639 			break;
640 
641 		/* Check status for errors */
642 		if (unlikely(stat & GRETH_TXBD_STATUS)) {
643 			dev->stats.tx_errors++;
644 			if (stat & GRETH_TXBD_ERR_AL)
645 				dev->stats.tx_aborted_errors++;
646 			if (stat & GRETH_TXBD_ERR_UE)
647 				dev->stats.tx_fifo_errors++;
648 		}
649 		dev->stats.tx_packets++;
650 		dev->stats.tx_bytes += greth->tx_bufs_length[greth->tx_last];
651 		greth->tx_last = NEXT_TX(greth->tx_last);
652 		greth->tx_free++;
653 	}
654 
655 	if (greth->tx_free > 0) {
656 		netif_wake_queue(dev);
657 	}
658 }
659 
660 static inline void greth_update_tx_stats(struct net_device *dev, u32 stat)
661 {
662 	/* Check status for errors */
663 	if (unlikely(stat & GRETH_TXBD_STATUS)) {
664 		dev->stats.tx_errors++;
665 		if (stat & GRETH_TXBD_ERR_AL)
666 			dev->stats.tx_aborted_errors++;
667 		if (stat & GRETH_TXBD_ERR_UE)
668 			dev->stats.tx_fifo_errors++;
669 		if (stat & GRETH_TXBD_ERR_LC)
670 			dev->stats.tx_aborted_errors++;
671 	}
672 	dev->stats.tx_packets++;
673 }
674 
675 static void greth_clean_tx_gbit(struct net_device *dev)
676 {
677 	struct greth_private *greth;
678 	struct greth_bd *bdp, *bdp_last_frag;
679 	struct sk_buff *skb = NULL;
680 	u32 stat;
681 	int nr_frags, i;
682 	u16 tx_last;
683 
684 	greth = netdev_priv(dev);
685 	tx_last = greth->tx_last;
686 
687 	while (tx_last != greth->tx_next) {
688 
689 		skb = greth->tx_skbuff[tx_last];
690 
691 		nr_frags = skb_shinfo(skb)->nr_frags;
692 
693 		/* We only clean fully completed SKBs */
694 		bdp_last_frag = greth->tx_bd_base + SKIP_TX(tx_last, nr_frags);
695 
696 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
697 		mb();
698 		stat = greth_read_bd(&bdp_last_frag->stat);
699 
700 		if (stat & GRETH_BD_EN)
701 			break;
702 
703 		greth->tx_skbuff[tx_last] = NULL;
704 
705 		greth_update_tx_stats(dev, stat);
706 		dev->stats.tx_bytes += skb->len;
707 
708 		bdp = greth->tx_bd_base + tx_last;
709 
710 		tx_last = NEXT_TX(tx_last);
711 
712 		dma_unmap_single(greth->dev,
713 				 greth_read_bd(&bdp->addr),
714 				 skb_headlen(skb),
715 				 DMA_TO_DEVICE);
716 
717 		for (i = 0; i < nr_frags; i++) {
718 			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
719 			bdp = greth->tx_bd_base + tx_last;
720 
721 			dma_unmap_page(greth->dev,
722 				       greth_read_bd(&bdp->addr),
723 				       skb_frag_size(frag),
724 				       DMA_TO_DEVICE);
725 
726 			tx_last = NEXT_TX(tx_last);
727 		}
728 		dev_kfree_skb(skb);
729 	}
730 	if (skb) { /* skb is set only if the above while loop was entered */
731 		wmb();
732 		greth->tx_last = tx_last;
733 
734 		if (netif_queue_stopped(dev) &&
735 		    (greth_num_free_bds(tx_last, greth->tx_next) >
736 		    (MAX_SKB_FRAGS+1)))
737 			netif_wake_queue(dev);
738 	}
739 }
740 
741 static int greth_rx(struct net_device *dev, int limit)
742 {
743 	struct greth_private *greth;
744 	struct greth_bd *bdp;
745 	struct sk_buff *skb;
746 	int pkt_len;
747 	int bad, count;
748 	u32 status, dma_addr;
749 	unsigned long flags;
750 
751 	greth = netdev_priv(dev);
752 
753 	for (count = 0; count < limit; ++count) {
754 
755 		bdp = greth->rx_bd_base + greth->rx_cur;
756 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
757 		mb();
758 		status = greth_read_bd(&bdp->stat);
759 
760 		if (unlikely(status & GRETH_BD_EN)) {
761 			break;
762 		}
763 
764 		dma_addr = greth_read_bd(&bdp->addr);
765 		bad = 0;
766 
767 		/* Check status for errors. */
768 		if (unlikely(status & GRETH_RXBD_STATUS)) {
769 			if (status & GRETH_RXBD_ERR_FT) {
770 				dev->stats.rx_length_errors++;
771 				bad = 1;
772 			}
773 			if (status & (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE)) {
774 				dev->stats.rx_frame_errors++;
775 				bad = 1;
776 			}
777 			if (status & GRETH_RXBD_ERR_CRC) {
778 				dev->stats.rx_crc_errors++;
779 				bad = 1;
780 			}
781 		}
782 		if (unlikely(bad)) {
783 			dev->stats.rx_errors++;
784 
785 		} else {
786 
787 			pkt_len = status & GRETH_BD_LEN;
788 
789 			skb = netdev_alloc_skb(dev, pkt_len + NET_IP_ALIGN);
790 
791 			if (unlikely(skb == NULL)) {
792 
793 				if (net_ratelimit())
794 					dev_warn(&dev->dev, "low on memory - " "packet dropped\n");
795 
796 				dev->stats.rx_dropped++;
797 
798 			} else {
799 				skb_reserve(skb, NET_IP_ALIGN);
800 
801 				dma_sync_single_for_cpu(greth->dev,
802 							dma_addr,
803 							pkt_len,
804 							DMA_FROM_DEVICE);
805 
806 				if (netif_msg_pktdata(greth))
807 					greth_print_rx_packet(phys_to_virt(dma_addr), pkt_len);
808 
809 				skb_put_data(skb, phys_to_virt(dma_addr),
810 					     pkt_len);
811 
812 				skb->protocol = eth_type_trans(skb, dev);
813 				dev->stats.rx_bytes += pkt_len;
814 				dev->stats.rx_packets++;
815 				netif_receive_skb(skb);
816 			}
817 		}
818 
819 		status = GRETH_BD_EN | GRETH_BD_IE;
820 		if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
821 			status |= GRETH_BD_WR;
822 		}
823 
824 		wmb();
825 		greth_write_bd(&bdp->stat, status);
826 
827 		dma_sync_single_for_device(greth->dev, dma_addr, MAX_FRAME_SIZE, DMA_FROM_DEVICE);
828 
829 		spin_lock_irqsave(&greth->devlock, flags); /* save from XMIT */
830 		greth_enable_rx(greth);
831 		spin_unlock_irqrestore(&greth->devlock, flags);
832 
833 		greth->rx_cur = NEXT_RX(greth->rx_cur);
834 	}
835 
836 	return count;
837 }
838 
839 static inline int hw_checksummed(u32 status)
840 {
841 
842 	if (status & GRETH_RXBD_IP_FRAG)
843 		return 0;
844 
845 	if (status & GRETH_RXBD_IP && status & GRETH_RXBD_IP_CSERR)
846 		return 0;
847 
848 	if (status & GRETH_RXBD_UDP && status & GRETH_RXBD_UDP_CSERR)
849 		return 0;
850 
851 	if (status & GRETH_RXBD_TCP && status & GRETH_RXBD_TCP_CSERR)
852 		return 0;
853 
854 	return 1;
855 }
856 
857 static int greth_rx_gbit(struct net_device *dev, int limit)
858 {
859 	struct greth_private *greth;
860 	struct greth_bd *bdp;
861 	struct sk_buff *skb, *newskb;
862 	int pkt_len;
863 	int bad, count = 0;
864 	u32 status, dma_addr;
865 	unsigned long flags;
866 
867 	greth = netdev_priv(dev);
868 
869 	for (count = 0; count < limit; ++count) {
870 
871 		bdp = greth->rx_bd_base + greth->rx_cur;
872 		skb = greth->rx_skbuff[greth->rx_cur];
873 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
874 		mb();
875 		status = greth_read_bd(&bdp->stat);
876 		bad = 0;
877 
878 		if (status & GRETH_BD_EN)
879 			break;
880 
881 		/* Check status for errors. */
882 		if (unlikely(status & GRETH_RXBD_STATUS)) {
883 
884 			if (status & GRETH_RXBD_ERR_FT) {
885 				dev->stats.rx_length_errors++;
886 				bad = 1;
887 			} else if (status &
888 				   (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE | GRETH_RXBD_ERR_LE)) {
889 				dev->stats.rx_frame_errors++;
890 				bad = 1;
891 			} else if (status & GRETH_RXBD_ERR_CRC) {
892 				dev->stats.rx_crc_errors++;
893 				bad = 1;
894 			}
895 		}
896 
897 		/* Allocate new skb to replace current, not needed if the
898 		 * current skb can be reused */
899 		if (!bad && (newskb=netdev_alloc_skb(dev, MAX_FRAME_SIZE + NET_IP_ALIGN))) {
900 			skb_reserve(newskb, NET_IP_ALIGN);
901 
902 			dma_addr = dma_map_single(greth->dev,
903 						      newskb->data,
904 						      MAX_FRAME_SIZE + NET_IP_ALIGN,
905 						      DMA_FROM_DEVICE);
906 
907 			if (!dma_mapping_error(greth->dev, dma_addr)) {
908 				/* Process the incoming frame. */
909 				pkt_len = status & GRETH_BD_LEN;
910 
911 				dma_unmap_single(greth->dev,
912 						 greth_read_bd(&bdp->addr),
913 						 MAX_FRAME_SIZE + NET_IP_ALIGN,
914 						 DMA_FROM_DEVICE);
915 
916 				if (netif_msg_pktdata(greth))
917 					greth_print_rx_packet(phys_to_virt(greth_read_bd(&bdp->addr)), pkt_len);
918 
919 				skb_put(skb, pkt_len);
920 
921 				if (dev->features & NETIF_F_RXCSUM && hw_checksummed(status))
922 					skb->ip_summed = CHECKSUM_UNNECESSARY;
923 				else
924 					skb_checksum_none_assert(skb);
925 
926 				skb->protocol = eth_type_trans(skb, dev);
927 				dev->stats.rx_packets++;
928 				dev->stats.rx_bytes += pkt_len;
929 				netif_receive_skb(skb);
930 
931 				greth->rx_skbuff[greth->rx_cur] = newskb;
932 				greth_write_bd(&bdp->addr, dma_addr);
933 			} else {
934 				if (net_ratelimit())
935 					dev_warn(greth->dev, "Could not create DMA mapping, dropping packet\n");
936 				dev_kfree_skb(newskb);
937 				/* reusing current skb, so it is a drop */
938 				dev->stats.rx_dropped++;
939 			}
940 		} else if (bad) {
941 			/* Bad Frame transfer, the skb is reused */
942 			dev->stats.rx_dropped++;
943 		} else {
944 			/* Failed Allocating a new skb. This is rather stupid
945 			 * but the current "filled" skb is reused, as if
946 			 * transfer failure. One could argue that RX descriptor
947 			 * table handling should be divided into cleaning and
948 			 * filling as the TX part of the driver
949 			 */
950 			if (net_ratelimit())
951 				dev_warn(greth->dev, "Could not allocate SKB, dropping packet\n");
952 			/* reusing current skb, so it is a drop */
953 			dev->stats.rx_dropped++;
954 		}
955 
956 		status = GRETH_BD_EN | GRETH_BD_IE;
957 		if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
958 			status |= GRETH_BD_WR;
959 		}
960 
961 		wmb();
962 		greth_write_bd(&bdp->stat, status);
963 		spin_lock_irqsave(&greth->devlock, flags);
964 		greth_enable_rx(greth);
965 		spin_unlock_irqrestore(&greth->devlock, flags);
966 		greth->rx_cur = NEXT_RX(greth->rx_cur);
967 	}
968 
969 	return count;
970 
971 }
972 
973 static int greth_poll(struct napi_struct *napi, int budget)
974 {
975 	struct greth_private *greth;
976 	int work_done = 0;
977 	unsigned long flags;
978 	u32 mask, ctrl;
979 	greth = container_of(napi, struct greth_private, napi);
980 
981 restart_txrx_poll:
982 	if (greth->gbit_mac) {
983 		greth_clean_tx_gbit(greth->netdev);
984 		work_done += greth_rx_gbit(greth->netdev, budget - work_done);
985 	} else {
986 		if (netif_queue_stopped(greth->netdev))
987 			greth_clean_tx(greth->netdev);
988 		work_done += greth_rx(greth->netdev, budget - work_done);
989 	}
990 
991 	if (work_done < budget) {
992 
993 		spin_lock_irqsave(&greth->devlock, flags);
994 
995 		ctrl = GRETH_REGLOAD(greth->regs->control);
996 		if ((greth->gbit_mac && (greth->tx_last != greth->tx_next)) ||
997 		    (!greth->gbit_mac && netif_queue_stopped(greth->netdev))) {
998 			GRETH_REGSAVE(greth->regs->control,
999 					ctrl | GRETH_TXI | GRETH_RXI);
1000 			mask = GRETH_INT_RX | GRETH_INT_RE |
1001 			       GRETH_INT_TX | GRETH_INT_TE;
1002 		} else {
1003 			GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_RXI);
1004 			mask = GRETH_INT_RX | GRETH_INT_RE;
1005 		}
1006 
1007 		if (GRETH_REGLOAD(greth->regs->status) & mask) {
1008 			GRETH_REGSAVE(greth->regs->control, ctrl);
1009 			spin_unlock_irqrestore(&greth->devlock, flags);
1010 			goto restart_txrx_poll;
1011 		} else {
1012 			napi_complete_done(napi, work_done);
1013 			spin_unlock_irqrestore(&greth->devlock, flags);
1014 		}
1015 	}
1016 
1017 	return work_done;
1018 }
1019 
1020 static int greth_set_mac_add(struct net_device *dev, void *p)
1021 {
1022 	struct sockaddr *addr = p;
1023 	struct greth_private *greth;
1024 	struct greth_regs *regs;
1025 
1026 	greth = netdev_priv(dev);
1027 	regs = greth->regs;
1028 
1029 	if (!is_valid_ether_addr(addr->sa_data))
1030 		return -EADDRNOTAVAIL;
1031 
1032 	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
1033 	GRETH_REGSAVE(regs->esa_msb, dev->dev_addr[0] << 8 | dev->dev_addr[1]);
1034 	GRETH_REGSAVE(regs->esa_lsb, dev->dev_addr[2] << 24 | dev->dev_addr[3] << 16 |
1035 		      dev->dev_addr[4] << 8 | dev->dev_addr[5]);
1036 
1037 	return 0;
1038 }
1039 
1040 static u32 greth_hash_get_index(__u8 *addr)
1041 {
1042 	return (ether_crc(6, addr)) & 0x3F;
1043 }
1044 
1045 static void greth_set_hash_filter(struct net_device *dev)
1046 {
1047 	struct netdev_hw_addr *ha;
1048 	struct greth_private *greth = netdev_priv(dev);
1049 	struct greth_regs *regs = greth->regs;
1050 	u32 mc_filter[2];
1051 	unsigned int bitnr;
1052 
1053 	mc_filter[0] = mc_filter[1] = 0;
1054 
1055 	netdev_for_each_mc_addr(ha, dev) {
1056 		bitnr = greth_hash_get_index(ha->addr);
1057 		mc_filter[bitnr >> 5] |= 1 << (bitnr & 31);
1058 	}
1059 
1060 	GRETH_REGSAVE(regs->hash_msb, mc_filter[1]);
1061 	GRETH_REGSAVE(regs->hash_lsb, mc_filter[0]);
1062 }
1063 
1064 static void greth_set_multicast_list(struct net_device *dev)
1065 {
1066 	int cfg;
1067 	struct greth_private *greth = netdev_priv(dev);
1068 	struct greth_regs *regs = greth->regs;
1069 
1070 	cfg = GRETH_REGLOAD(regs->control);
1071 	if (dev->flags & IFF_PROMISC)
1072 		cfg |= GRETH_CTRL_PR;
1073 	else
1074 		cfg &= ~GRETH_CTRL_PR;
1075 
1076 	if (greth->multicast) {
1077 		if (dev->flags & IFF_ALLMULTI) {
1078 			GRETH_REGSAVE(regs->hash_msb, -1);
1079 			GRETH_REGSAVE(regs->hash_lsb, -1);
1080 			cfg |= GRETH_CTRL_MCEN;
1081 			GRETH_REGSAVE(regs->control, cfg);
1082 			return;
1083 		}
1084 
1085 		if (netdev_mc_empty(dev)) {
1086 			cfg &= ~GRETH_CTRL_MCEN;
1087 			GRETH_REGSAVE(regs->control, cfg);
1088 			return;
1089 		}
1090 
1091 		/* Setup multicast filter */
1092 		greth_set_hash_filter(dev);
1093 		cfg |= GRETH_CTRL_MCEN;
1094 	}
1095 	GRETH_REGSAVE(regs->control, cfg);
1096 }
1097 
1098 static u32 greth_get_msglevel(struct net_device *dev)
1099 {
1100 	struct greth_private *greth = netdev_priv(dev);
1101 	return greth->msg_enable;
1102 }
1103 
1104 static void greth_set_msglevel(struct net_device *dev, u32 value)
1105 {
1106 	struct greth_private *greth = netdev_priv(dev);
1107 	greth->msg_enable = value;
1108 }
1109 
1110 static int greth_get_regs_len(struct net_device *dev)
1111 {
1112 	return sizeof(struct greth_regs);
1113 }
1114 
1115 static void greth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1116 {
1117 	struct greth_private *greth = netdev_priv(dev);
1118 
1119 	strlcpy(info->driver, dev_driver_string(greth->dev),
1120 		sizeof(info->driver));
1121 	strlcpy(info->version, "revision: 1.0", sizeof(info->version));
1122 	strlcpy(info->bus_info, greth->dev->bus->name, sizeof(info->bus_info));
1123 	strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
1124 }
1125 
1126 static void greth_get_regs(struct net_device *dev, struct ethtool_regs *regs, void *p)
1127 {
1128 	int i;
1129 	struct greth_private *greth = netdev_priv(dev);
1130 	u32 __iomem *greth_regs = (u32 __iomem *) greth->regs;
1131 	u32 *buff = p;
1132 
1133 	for (i = 0; i < sizeof(struct greth_regs) / sizeof(u32); i++)
1134 		buff[i] = greth_read_bd(&greth_regs[i]);
1135 }
1136 
1137 static const struct ethtool_ops greth_ethtool_ops = {
1138 	.get_msglevel		= greth_get_msglevel,
1139 	.set_msglevel		= greth_set_msglevel,
1140 	.get_drvinfo		= greth_get_drvinfo,
1141 	.get_regs_len           = greth_get_regs_len,
1142 	.get_regs               = greth_get_regs,
1143 	.get_link		= ethtool_op_get_link,
1144 	.get_link_ksettings	= phy_ethtool_get_link_ksettings,
1145 	.set_link_ksettings	= phy_ethtool_set_link_ksettings,
1146 };
1147 
1148 static struct net_device_ops greth_netdev_ops = {
1149 	.ndo_open		= greth_open,
1150 	.ndo_stop		= greth_close,
1151 	.ndo_start_xmit		= greth_start_xmit,
1152 	.ndo_set_mac_address	= greth_set_mac_add,
1153 	.ndo_validate_addr	= eth_validate_addr,
1154 };
1155 
1156 static inline int wait_for_mdio(struct greth_private *greth)
1157 {
1158 	unsigned long timeout = jiffies + 4*HZ/100;
1159 	while (GRETH_REGLOAD(greth->regs->mdio) & GRETH_MII_BUSY) {
1160 		if (time_after(jiffies, timeout))
1161 			return 0;
1162 	}
1163 	return 1;
1164 }
1165 
1166 static int greth_mdio_read(struct mii_bus *bus, int phy, int reg)
1167 {
1168 	struct greth_private *greth = bus->priv;
1169 	int data;
1170 
1171 	if (!wait_for_mdio(greth))
1172 		return -EBUSY;
1173 
1174 	GRETH_REGSAVE(greth->regs->mdio, ((phy & 0x1F) << 11) | ((reg & 0x1F) << 6) | 2);
1175 
1176 	if (!wait_for_mdio(greth))
1177 		return -EBUSY;
1178 
1179 	if (!(GRETH_REGLOAD(greth->regs->mdio) & GRETH_MII_NVALID)) {
1180 		data = (GRETH_REGLOAD(greth->regs->mdio) >> 16) & 0xFFFF;
1181 		return data;
1182 
1183 	} else {
1184 		return -1;
1185 	}
1186 }
1187 
1188 static int greth_mdio_write(struct mii_bus *bus, int phy, int reg, u16 val)
1189 {
1190 	struct greth_private *greth = bus->priv;
1191 
1192 	if (!wait_for_mdio(greth))
1193 		return -EBUSY;
1194 
1195 	GRETH_REGSAVE(greth->regs->mdio,
1196 		      ((val & 0xFFFF) << 16) | ((phy & 0x1F) << 11) | ((reg & 0x1F) << 6) | 1);
1197 
1198 	if (!wait_for_mdio(greth))
1199 		return -EBUSY;
1200 
1201 	return 0;
1202 }
1203 
1204 static void greth_link_change(struct net_device *dev)
1205 {
1206 	struct greth_private *greth = netdev_priv(dev);
1207 	struct phy_device *phydev = dev->phydev;
1208 	unsigned long flags;
1209 	int status_change = 0;
1210 	u32 ctrl;
1211 
1212 	spin_lock_irqsave(&greth->devlock, flags);
1213 
1214 	if (phydev->link) {
1215 
1216 		if ((greth->speed != phydev->speed) || (greth->duplex != phydev->duplex)) {
1217 			ctrl = GRETH_REGLOAD(greth->regs->control) &
1218 			       ~(GRETH_CTRL_FD | GRETH_CTRL_SP | GRETH_CTRL_GB);
1219 
1220 			if (phydev->duplex)
1221 				ctrl |= GRETH_CTRL_FD;
1222 
1223 			if (phydev->speed == SPEED_100)
1224 				ctrl |= GRETH_CTRL_SP;
1225 			else if (phydev->speed == SPEED_1000)
1226 				ctrl |= GRETH_CTRL_GB;
1227 
1228 			GRETH_REGSAVE(greth->regs->control, ctrl);
1229 			greth->speed = phydev->speed;
1230 			greth->duplex = phydev->duplex;
1231 			status_change = 1;
1232 		}
1233 	}
1234 
1235 	if (phydev->link != greth->link) {
1236 		if (!phydev->link) {
1237 			greth->speed = 0;
1238 			greth->duplex = -1;
1239 		}
1240 		greth->link = phydev->link;
1241 
1242 		status_change = 1;
1243 	}
1244 
1245 	spin_unlock_irqrestore(&greth->devlock, flags);
1246 
1247 	if (status_change) {
1248 		if (phydev->link)
1249 			pr_debug("%s: link up (%d/%s)\n",
1250 				dev->name, phydev->speed,
1251 				DUPLEX_FULL == phydev->duplex ? "Full" : "Half");
1252 		else
1253 			pr_debug("%s: link down\n", dev->name);
1254 	}
1255 }
1256 
1257 static int greth_mdio_probe(struct net_device *dev)
1258 {
1259 	struct greth_private *greth = netdev_priv(dev);
1260 	struct phy_device *phy = NULL;
1261 	int ret;
1262 
1263 	/* Find the first PHY */
1264 	phy = phy_find_first(greth->mdio);
1265 
1266 	if (!phy) {
1267 		if (netif_msg_probe(greth))
1268 			dev_err(&dev->dev, "no PHY found\n");
1269 		return -ENXIO;
1270 	}
1271 
1272 	ret = phy_connect_direct(dev, phy, &greth_link_change,
1273 				 greth->gbit_mac ? PHY_INTERFACE_MODE_GMII : PHY_INTERFACE_MODE_MII);
1274 	if (ret) {
1275 		if (netif_msg_ifup(greth))
1276 			dev_err(&dev->dev, "could not attach to PHY\n");
1277 		return ret;
1278 	}
1279 
1280 	if (greth->gbit_mac)
1281 		phy_set_max_speed(phy, SPEED_1000);
1282 	else
1283 		phy_set_max_speed(phy, SPEED_100);
1284 
1285 	linkmode_copy(phy->advertising, phy->supported);
1286 
1287 	greth->link = 0;
1288 	greth->speed = 0;
1289 	greth->duplex = -1;
1290 
1291 	return 0;
1292 }
1293 
1294 static int greth_mdio_init(struct greth_private *greth)
1295 {
1296 	int ret;
1297 	unsigned long timeout;
1298 	struct net_device *ndev = greth->netdev;
1299 
1300 	greth->mdio = mdiobus_alloc();
1301 	if (!greth->mdio) {
1302 		return -ENOMEM;
1303 	}
1304 
1305 	greth->mdio->name = "greth-mdio";
1306 	snprintf(greth->mdio->id, MII_BUS_ID_SIZE, "%s-%d", greth->mdio->name, greth->irq);
1307 	greth->mdio->read = greth_mdio_read;
1308 	greth->mdio->write = greth_mdio_write;
1309 	greth->mdio->priv = greth;
1310 
1311 	ret = mdiobus_register(greth->mdio);
1312 	if (ret) {
1313 		goto error;
1314 	}
1315 
1316 	ret = greth_mdio_probe(greth->netdev);
1317 	if (ret) {
1318 		if (netif_msg_probe(greth))
1319 			dev_err(&greth->netdev->dev, "failed to probe MDIO bus\n");
1320 		goto unreg_mdio;
1321 	}
1322 
1323 	phy_start(ndev->phydev);
1324 
1325 	/* If Ethernet debug link is used make autoneg happen right away */
1326 	if (greth->edcl && greth_edcl == 1) {
1327 		phy_start_aneg(ndev->phydev);
1328 		timeout = jiffies + 6*HZ;
1329 		while (!phy_aneg_done(ndev->phydev) &&
1330 		       time_before(jiffies, timeout)) {
1331 		}
1332 		phy_read_status(ndev->phydev);
1333 		greth_link_change(greth->netdev);
1334 	}
1335 
1336 	return 0;
1337 
1338 unreg_mdio:
1339 	mdiobus_unregister(greth->mdio);
1340 error:
1341 	mdiobus_free(greth->mdio);
1342 	return ret;
1343 }
1344 
1345 /* Initialize the GRETH MAC */
1346 static int greth_of_probe(struct platform_device *ofdev)
1347 {
1348 	struct net_device *dev;
1349 	struct greth_private *greth;
1350 	struct greth_regs *regs;
1351 
1352 	int i;
1353 	int err;
1354 	int tmp;
1355 	unsigned long timeout;
1356 
1357 	dev = alloc_etherdev(sizeof(struct greth_private));
1358 
1359 	if (dev == NULL)
1360 		return -ENOMEM;
1361 
1362 	greth = netdev_priv(dev);
1363 	greth->netdev = dev;
1364 	greth->dev = &ofdev->dev;
1365 
1366 	if (greth_debug > 0)
1367 		greth->msg_enable = greth_debug;
1368 	else
1369 		greth->msg_enable = GRETH_DEF_MSG_ENABLE;
1370 
1371 	spin_lock_init(&greth->devlock);
1372 
1373 	greth->regs = of_ioremap(&ofdev->resource[0], 0,
1374 				 resource_size(&ofdev->resource[0]),
1375 				 "grlib-greth regs");
1376 
1377 	if (greth->regs == NULL) {
1378 		if (netif_msg_probe(greth))
1379 			dev_err(greth->dev, "ioremap failure.\n");
1380 		err = -EIO;
1381 		goto error1;
1382 	}
1383 
1384 	regs = greth->regs;
1385 	greth->irq = ofdev->archdata.irqs[0];
1386 
1387 	dev_set_drvdata(greth->dev, dev);
1388 	SET_NETDEV_DEV(dev, greth->dev);
1389 
1390 	if (netif_msg_probe(greth))
1391 		dev_dbg(greth->dev, "resetting controller.\n");
1392 
1393 	/* Reset the controller. */
1394 	GRETH_REGSAVE(regs->control, GRETH_RESET);
1395 
1396 	/* Wait for MAC to reset itself */
1397 	timeout = jiffies + HZ/100;
1398 	while (GRETH_REGLOAD(regs->control) & GRETH_RESET) {
1399 		if (time_after(jiffies, timeout)) {
1400 			err = -EIO;
1401 			if (netif_msg_probe(greth))
1402 				dev_err(greth->dev, "timeout when waiting for reset.\n");
1403 			goto error2;
1404 		}
1405 	}
1406 
1407 	/* Get default PHY address  */
1408 	greth->phyaddr = (GRETH_REGLOAD(regs->mdio) >> 11) & 0x1F;
1409 
1410 	/* Check if we have GBIT capable MAC */
1411 	tmp = GRETH_REGLOAD(regs->control);
1412 	greth->gbit_mac = (tmp >> 27) & 1;
1413 
1414 	/* Check for multicast capability */
1415 	greth->multicast = (tmp >> 25) & 1;
1416 
1417 	greth->edcl = (tmp >> 31) & 1;
1418 
1419 	/* If we have EDCL we disable the EDCL speed-duplex FSM so
1420 	 * it doesn't interfere with the software */
1421 	if (greth->edcl != 0)
1422 		GRETH_REGORIN(regs->control, GRETH_CTRL_DISDUPLEX);
1423 
1424 	/* Check if MAC can handle MDIO interrupts */
1425 	greth->mdio_int_en = (tmp >> 26) & 1;
1426 
1427 	err = greth_mdio_init(greth);
1428 	if (err) {
1429 		if (netif_msg_probe(greth))
1430 			dev_err(greth->dev, "failed to register MDIO bus\n");
1431 		goto error2;
1432 	}
1433 
1434 	/* Allocate TX descriptor ring in coherent memory */
1435 	greth->tx_bd_base = dma_alloc_coherent(greth->dev, 1024,
1436 					       &greth->tx_bd_base_phys,
1437 					       GFP_KERNEL);
1438 	if (!greth->tx_bd_base) {
1439 		err = -ENOMEM;
1440 		goto error3;
1441 	}
1442 
1443 	/* Allocate RX descriptor ring in coherent memory */
1444 	greth->rx_bd_base = dma_alloc_coherent(greth->dev, 1024,
1445 					       &greth->rx_bd_base_phys,
1446 					       GFP_KERNEL);
1447 	if (!greth->rx_bd_base) {
1448 		err = -ENOMEM;
1449 		goto error4;
1450 	}
1451 
1452 	/* Get MAC address from: module param, OF property or ID prom */
1453 	for (i = 0; i < 6; i++) {
1454 		if (macaddr[i] != 0)
1455 			break;
1456 	}
1457 	if (i == 6) {
1458 		const u8 *addr;
1459 
1460 		addr = of_get_mac_address(ofdev->dev.of_node);
1461 		if (!IS_ERR(addr)) {
1462 			for (i = 0; i < 6; i++)
1463 				macaddr[i] = (unsigned int) addr[i];
1464 		} else {
1465 #ifdef CONFIG_SPARC
1466 			for (i = 0; i < 6; i++)
1467 				macaddr[i] = (unsigned int) idprom->id_ethaddr[i];
1468 #endif
1469 		}
1470 	}
1471 
1472 	for (i = 0; i < 6; i++)
1473 		dev->dev_addr[i] = macaddr[i];
1474 
1475 	macaddr[5]++;
1476 
1477 	if (!is_valid_ether_addr(&dev->dev_addr[0])) {
1478 		if (netif_msg_probe(greth))
1479 			dev_err(greth->dev, "no valid ethernet address, aborting.\n");
1480 		err = -EINVAL;
1481 		goto error5;
1482 	}
1483 
1484 	GRETH_REGSAVE(regs->esa_msb, dev->dev_addr[0] << 8 | dev->dev_addr[1]);
1485 	GRETH_REGSAVE(regs->esa_lsb, dev->dev_addr[2] << 24 | dev->dev_addr[3] << 16 |
1486 		      dev->dev_addr[4] << 8 | dev->dev_addr[5]);
1487 
1488 	/* Clear all pending interrupts except PHY irq */
1489 	GRETH_REGSAVE(regs->status, 0xFF);
1490 
1491 	if (greth->gbit_mac) {
1492 		dev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM |
1493 			NETIF_F_RXCSUM;
1494 		dev->features = dev->hw_features | NETIF_F_HIGHDMA;
1495 		greth_netdev_ops.ndo_start_xmit = greth_start_xmit_gbit;
1496 	}
1497 
1498 	if (greth->multicast) {
1499 		greth_netdev_ops.ndo_set_rx_mode = greth_set_multicast_list;
1500 		dev->flags |= IFF_MULTICAST;
1501 	} else {
1502 		dev->flags &= ~IFF_MULTICAST;
1503 	}
1504 
1505 	dev->netdev_ops = &greth_netdev_ops;
1506 	dev->ethtool_ops = &greth_ethtool_ops;
1507 
1508 	err = register_netdev(dev);
1509 	if (err) {
1510 		if (netif_msg_probe(greth))
1511 			dev_err(greth->dev, "netdevice registration failed.\n");
1512 		goto error5;
1513 	}
1514 
1515 	/* setup NAPI */
1516 	netif_napi_add(dev, &greth->napi, greth_poll, 64);
1517 
1518 	return 0;
1519 
1520 error5:
1521 	dma_free_coherent(greth->dev, 1024, greth->rx_bd_base, greth->rx_bd_base_phys);
1522 error4:
1523 	dma_free_coherent(greth->dev, 1024, greth->tx_bd_base, greth->tx_bd_base_phys);
1524 error3:
1525 	mdiobus_unregister(greth->mdio);
1526 error2:
1527 	of_iounmap(&ofdev->resource[0], greth->regs, resource_size(&ofdev->resource[0]));
1528 error1:
1529 	free_netdev(dev);
1530 	return err;
1531 }
1532 
1533 static int greth_of_remove(struct platform_device *of_dev)
1534 {
1535 	struct net_device *ndev = platform_get_drvdata(of_dev);
1536 	struct greth_private *greth = netdev_priv(ndev);
1537 
1538 	/* Free descriptor areas */
1539 	dma_free_coherent(&of_dev->dev, 1024, greth->rx_bd_base, greth->rx_bd_base_phys);
1540 
1541 	dma_free_coherent(&of_dev->dev, 1024, greth->tx_bd_base, greth->tx_bd_base_phys);
1542 
1543 	if (ndev->phydev)
1544 		phy_stop(ndev->phydev);
1545 	mdiobus_unregister(greth->mdio);
1546 
1547 	unregister_netdev(ndev);
1548 	free_netdev(ndev);
1549 
1550 	of_iounmap(&of_dev->resource[0], greth->regs, resource_size(&of_dev->resource[0]));
1551 
1552 	return 0;
1553 }
1554 
1555 static const struct of_device_id greth_of_match[] = {
1556 	{
1557 	 .name = "GAISLER_ETHMAC",
1558 	 },
1559 	{
1560 	 .name = "01_01d",
1561 	 },
1562 	{},
1563 };
1564 
1565 MODULE_DEVICE_TABLE(of, greth_of_match);
1566 
1567 static struct platform_driver greth_of_driver = {
1568 	.driver = {
1569 		.name = "grlib-greth",
1570 		.of_match_table = greth_of_match,
1571 	},
1572 	.probe = greth_of_probe,
1573 	.remove = greth_of_remove,
1574 };
1575 
1576 module_platform_driver(greth_of_driver);
1577 
1578 MODULE_AUTHOR("Aeroflex Gaisler AB.");
1579 MODULE_DESCRIPTION("Aeroflex Gaisler Ethernet MAC driver");
1580 MODULE_LICENSE("GPL");
1581