1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Aeroflex Gaisler GRETH 10/100/1G Ethernet MAC.
4  *
5  * 2005-2010 (c) Aeroflex Gaisler AB
6  *
7  * This driver supports GRETH 10/100 and GRETH 10/100/1G Ethernet MACs
8  * available in the GRLIB VHDL IP core library.
9  *
10  * Full documentation of both cores can be found here:
11  * http://www.gaisler.com/products/grlib/grip.pdf
12  *
13  * The Gigabit version supports scatter/gather DMA, any alignment of
14  * buffers and checksum offloading.
15  *
16  * Contributors: Kristoffer Glembo
17  *               Daniel Hellstrom
18  *               Marko Isomaki
19  */
20 
21 #include <linux/dma-mapping.h>
22 #include <linux/module.h>
23 #include <linux/uaccess.h>
24 #include <linux/interrupt.h>
25 #include <linux/netdevice.h>
26 #include <linux/etherdevice.h>
27 #include <linux/ethtool.h>
28 #include <linux/skbuff.h>
29 #include <linux/io.h>
30 #include <linux/crc32.h>
31 #include <linux/mii.h>
32 #include <linux/of_device.h>
33 #include <linux/of_net.h>
34 #include <linux/of_platform.h>
35 #include <linux/slab.h>
36 #include <asm/cacheflush.h>
37 #include <asm/byteorder.h>
38 
39 #ifdef CONFIG_SPARC
40 #include <asm/idprom.h>
41 #endif
42 
43 #include "greth.h"
44 
45 #define GRETH_DEF_MSG_ENABLE	  \
46 	(NETIF_MSG_DRV		| \
47 	 NETIF_MSG_PROBE	| \
48 	 NETIF_MSG_LINK		| \
49 	 NETIF_MSG_IFDOWN	| \
50 	 NETIF_MSG_IFUP		| \
51 	 NETIF_MSG_RX_ERR	| \
52 	 NETIF_MSG_TX_ERR)
53 
54 static int greth_debug = -1;	/* -1 == use GRETH_DEF_MSG_ENABLE as value */
55 module_param(greth_debug, int, 0);
56 MODULE_PARM_DESC(greth_debug, "GRETH bitmapped debugging message enable value");
57 
58 /* Accept MAC address of the form macaddr=0x08,0x00,0x20,0x30,0x40,0x50 */
59 static int macaddr[6];
60 module_param_array(macaddr, int, NULL, 0);
61 MODULE_PARM_DESC(macaddr, "GRETH Ethernet MAC address");
62 
63 static int greth_edcl = 1;
64 module_param(greth_edcl, int, 0);
65 MODULE_PARM_DESC(greth_edcl, "GRETH EDCL usage indicator. Set to 1 if EDCL is used.");
66 
67 static int greth_open(struct net_device *dev);
68 static netdev_tx_t greth_start_xmit(struct sk_buff *skb,
69 	   struct net_device *dev);
70 static netdev_tx_t greth_start_xmit_gbit(struct sk_buff *skb,
71 	   struct net_device *dev);
72 static int greth_rx(struct net_device *dev, int limit);
73 static int greth_rx_gbit(struct net_device *dev, int limit);
74 static void greth_clean_tx(struct net_device *dev);
75 static void greth_clean_tx_gbit(struct net_device *dev);
76 static irqreturn_t greth_interrupt(int irq, void *dev_id);
77 static int greth_close(struct net_device *dev);
78 static int greth_set_mac_add(struct net_device *dev, void *p);
79 static void greth_set_multicast_list(struct net_device *dev);
80 
81 #define GRETH_REGLOAD(a)	    (be32_to_cpu(__raw_readl(&(a))))
82 #define GRETH_REGSAVE(a, v)         (__raw_writel(cpu_to_be32(v), &(a)))
83 #define GRETH_REGORIN(a, v)         (GRETH_REGSAVE(a, (GRETH_REGLOAD(a) | (v))))
84 #define GRETH_REGANDIN(a, v)        (GRETH_REGSAVE(a, (GRETH_REGLOAD(a) & (v))))
85 
86 #define NEXT_TX(N)      (((N) + 1) & GRETH_TXBD_NUM_MASK)
87 #define SKIP_TX(N, C)   (((N) + C) & GRETH_TXBD_NUM_MASK)
88 #define NEXT_RX(N)      (((N) + 1) & GRETH_RXBD_NUM_MASK)
89 
90 static void greth_print_rx_packet(void *addr, int len)
91 {
92 	print_hex_dump(KERN_DEBUG, "RX: ", DUMP_PREFIX_OFFSET, 16, 1,
93 			addr, len, true);
94 }
95 
96 static void greth_print_tx_packet(struct sk_buff *skb)
97 {
98 	int i;
99 	int length;
100 
101 	if (skb_shinfo(skb)->nr_frags == 0)
102 		length = skb->len;
103 	else
104 		length = skb_headlen(skb);
105 
106 	print_hex_dump(KERN_DEBUG, "TX: ", DUMP_PREFIX_OFFSET, 16, 1,
107 			skb->data, length, true);
108 
109 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
110 
111 		print_hex_dump(KERN_DEBUG, "TX: ", DUMP_PREFIX_OFFSET, 16, 1,
112 			       skb_frag_address(&skb_shinfo(skb)->frags[i]),
113 			       skb_frag_size(&skb_shinfo(skb)->frags[i]), true);
114 	}
115 }
116 
117 static inline void greth_enable_tx(struct greth_private *greth)
118 {
119 	wmb();
120 	GRETH_REGORIN(greth->regs->control, GRETH_TXEN);
121 }
122 
123 static inline void greth_enable_tx_and_irq(struct greth_private *greth)
124 {
125 	wmb(); /* BDs must been written to memory before enabling TX */
126 	GRETH_REGORIN(greth->regs->control, GRETH_TXEN | GRETH_TXI);
127 }
128 
129 static inline void greth_disable_tx(struct greth_private *greth)
130 {
131 	GRETH_REGANDIN(greth->regs->control, ~GRETH_TXEN);
132 }
133 
134 static inline void greth_enable_rx(struct greth_private *greth)
135 {
136 	wmb();
137 	GRETH_REGORIN(greth->regs->control, GRETH_RXEN);
138 }
139 
140 static inline void greth_disable_rx(struct greth_private *greth)
141 {
142 	GRETH_REGANDIN(greth->regs->control, ~GRETH_RXEN);
143 }
144 
145 static inline void greth_enable_irqs(struct greth_private *greth)
146 {
147 	GRETH_REGORIN(greth->regs->control, GRETH_RXI | GRETH_TXI);
148 }
149 
150 static inline void greth_disable_irqs(struct greth_private *greth)
151 {
152 	GRETH_REGANDIN(greth->regs->control, ~(GRETH_RXI|GRETH_TXI));
153 }
154 
155 static inline void greth_write_bd(u32 *bd, u32 val)
156 {
157 	__raw_writel(cpu_to_be32(val), bd);
158 }
159 
160 static inline u32 greth_read_bd(u32 *bd)
161 {
162 	return be32_to_cpu(__raw_readl(bd));
163 }
164 
165 static void greth_clean_rings(struct greth_private *greth)
166 {
167 	int i;
168 	struct greth_bd *rx_bdp = greth->rx_bd_base;
169 	struct greth_bd *tx_bdp = greth->tx_bd_base;
170 
171 	if (greth->gbit_mac) {
172 
173 		/* Free and unmap RX buffers */
174 		for (i = 0; i < GRETH_RXBD_NUM; i++, rx_bdp++) {
175 			if (greth->rx_skbuff[i] != NULL) {
176 				dev_kfree_skb(greth->rx_skbuff[i]);
177 				dma_unmap_single(greth->dev,
178 						 greth_read_bd(&rx_bdp->addr),
179 						 MAX_FRAME_SIZE+NET_IP_ALIGN,
180 						 DMA_FROM_DEVICE);
181 			}
182 		}
183 
184 		/* TX buffers */
185 		while (greth->tx_free < GRETH_TXBD_NUM) {
186 
187 			struct sk_buff *skb = greth->tx_skbuff[greth->tx_last];
188 			int nr_frags = skb_shinfo(skb)->nr_frags;
189 			tx_bdp = greth->tx_bd_base + greth->tx_last;
190 			greth->tx_last = NEXT_TX(greth->tx_last);
191 
192 			dma_unmap_single(greth->dev,
193 					 greth_read_bd(&tx_bdp->addr),
194 					 skb_headlen(skb),
195 					 DMA_TO_DEVICE);
196 
197 			for (i = 0; i < nr_frags; i++) {
198 				skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
199 				tx_bdp = greth->tx_bd_base + greth->tx_last;
200 
201 				dma_unmap_page(greth->dev,
202 					       greth_read_bd(&tx_bdp->addr),
203 					       skb_frag_size(frag),
204 					       DMA_TO_DEVICE);
205 
206 				greth->tx_last = NEXT_TX(greth->tx_last);
207 			}
208 			greth->tx_free += nr_frags+1;
209 			dev_kfree_skb(skb);
210 		}
211 
212 
213 	} else { /* 10/100 Mbps MAC */
214 
215 		for (i = 0; i < GRETH_RXBD_NUM; i++, rx_bdp++) {
216 			kfree(greth->rx_bufs[i]);
217 			dma_unmap_single(greth->dev,
218 					 greth_read_bd(&rx_bdp->addr),
219 					 MAX_FRAME_SIZE,
220 					 DMA_FROM_DEVICE);
221 		}
222 		for (i = 0; i < GRETH_TXBD_NUM; i++, tx_bdp++) {
223 			kfree(greth->tx_bufs[i]);
224 			dma_unmap_single(greth->dev,
225 					 greth_read_bd(&tx_bdp->addr),
226 					 MAX_FRAME_SIZE,
227 					 DMA_TO_DEVICE);
228 		}
229 	}
230 }
231 
232 static int greth_init_rings(struct greth_private *greth)
233 {
234 	struct sk_buff *skb;
235 	struct greth_bd *rx_bd, *tx_bd;
236 	u32 dma_addr;
237 	int i;
238 
239 	rx_bd = greth->rx_bd_base;
240 	tx_bd = greth->tx_bd_base;
241 
242 	/* Initialize descriptor rings and buffers */
243 	if (greth->gbit_mac) {
244 
245 		for (i = 0; i < GRETH_RXBD_NUM; i++) {
246 			skb = netdev_alloc_skb(greth->netdev, MAX_FRAME_SIZE+NET_IP_ALIGN);
247 			if (skb == NULL) {
248 				if (netif_msg_ifup(greth))
249 					dev_err(greth->dev, "Error allocating DMA ring.\n");
250 				goto cleanup;
251 			}
252 			skb_reserve(skb, NET_IP_ALIGN);
253 			dma_addr = dma_map_single(greth->dev,
254 						  skb->data,
255 						  MAX_FRAME_SIZE+NET_IP_ALIGN,
256 						  DMA_FROM_DEVICE);
257 
258 			if (dma_mapping_error(greth->dev, dma_addr)) {
259 				if (netif_msg_ifup(greth))
260 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
261 				goto cleanup;
262 			}
263 			greth->rx_skbuff[i] = skb;
264 			greth_write_bd(&rx_bd[i].addr, dma_addr);
265 			greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
266 		}
267 
268 	} else {
269 
270 		/* 10/100 MAC uses a fixed set of buffers and copy to/from SKBs */
271 		for (i = 0; i < GRETH_RXBD_NUM; i++) {
272 
273 			greth->rx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);
274 
275 			if (greth->rx_bufs[i] == NULL) {
276 				if (netif_msg_ifup(greth))
277 					dev_err(greth->dev, "Error allocating DMA ring.\n");
278 				goto cleanup;
279 			}
280 
281 			dma_addr = dma_map_single(greth->dev,
282 						  greth->rx_bufs[i],
283 						  MAX_FRAME_SIZE,
284 						  DMA_FROM_DEVICE);
285 
286 			if (dma_mapping_error(greth->dev, dma_addr)) {
287 				if (netif_msg_ifup(greth))
288 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
289 				goto cleanup;
290 			}
291 			greth_write_bd(&rx_bd[i].addr, dma_addr);
292 			greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
293 		}
294 		for (i = 0; i < GRETH_TXBD_NUM; i++) {
295 
296 			greth->tx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);
297 
298 			if (greth->tx_bufs[i] == NULL) {
299 				if (netif_msg_ifup(greth))
300 					dev_err(greth->dev, "Error allocating DMA ring.\n");
301 				goto cleanup;
302 			}
303 
304 			dma_addr = dma_map_single(greth->dev,
305 						  greth->tx_bufs[i],
306 						  MAX_FRAME_SIZE,
307 						  DMA_TO_DEVICE);
308 
309 			if (dma_mapping_error(greth->dev, dma_addr)) {
310 				if (netif_msg_ifup(greth))
311 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
312 				goto cleanup;
313 			}
314 			greth_write_bd(&tx_bd[i].addr, dma_addr);
315 			greth_write_bd(&tx_bd[i].stat, 0);
316 		}
317 	}
318 	greth_write_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat,
319 		       greth_read_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat) | GRETH_BD_WR);
320 
321 	/* Initialize pointers. */
322 	greth->rx_cur = 0;
323 	greth->tx_next = 0;
324 	greth->tx_last = 0;
325 	greth->tx_free = GRETH_TXBD_NUM;
326 
327 	/* Initialize descriptor base address */
328 	GRETH_REGSAVE(greth->regs->tx_desc_p, greth->tx_bd_base_phys);
329 	GRETH_REGSAVE(greth->regs->rx_desc_p, greth->rx_bd_base_phys);
330 
331 	return 0;
332 
333 cleanup:
334 	greth_clean_rings(greth);
335 	return -ENOMEM;
336 }
337 
338 static int greth_open(struct net_device *dev)
339 {
340 	struct greth_private *greth = netdev_priv(dev);
341 	int err;
342 
343 	err = greth_init_rings(greth);
344 	if (err) {
345 		if (netif_msg_ifup(greth))
346 			dev_err(&dev->dev, "Could not allocate memory for DMA rings\n");
347 		return err;
348 	}
349 
350 	err = request_irq(greth->irq, greth_interrupt, 0, "eth", (void *) dev);
351 	if (err) {
352 		if (netif_msg_ifup(greth))
353 			dev_err(&dev->dev, "Could not allocate interrupt %d\n", dev->irq);
354 		greth_clean_rings(greth);
355 		return err;
356 	}
357 
358 	if (netif_msg_ifup(greth))
359 		dev_dbg(&dev->dev, " starting queue\n");
360 	netif_start_queue(dev);
361 
362 	GRETH_REGSAVE(greth->regs->status, 0xFF);
363 
364 	napi_enable(&greth->napi);
365 
366 	greth_enable_irqs(greth);
367 	greth_enable_tx(greth);
368 	greth_enable_rx(greth);
369 	return 0;
370 
371 }
372 
373 static int greth_close(struct net_device *dev)
374 {
375 	struct greth_private *greth = netdev_priv(dev);
376 
377 	napi_disable(&greth->napi);
378 
379 	greth_disable_irqs(greth);
380 	greth_disable_tx(greth);
381 	greth_disable_rx(greth);
382 
383 	netif_stop_queue(dev);
384 
385 	free_irq(greth->irq, (void *) dev);
386 
387 	greth_clean_rings(greth);
388 
389 	return 0;
390 }
391 
392 static netdev_tx_t
393 greth_start_xmit(struct sk_buff *skb, struct net_device *dev)
394 {
395 	struct greth_private *greth = netdev_priv(dev);
396 	struct greth_bd *bdp;
397 	int err = NETDEV_TX_OK;
398 	u32 status, dma_addr, ctrl;
399 	unsigned long flags;
400 
401 	/* Clean TX Ring */
402 	greth_clean_tx(greth->netdev);
403 
404 	if (unlikely(greth->tx_free <= 0)) {
405 		spin_lock_irqsave(&greth->devlock, flags);/*save from poll/irq*/
406 		ctrl = GRETH_REGLOAD(greth->regs->control);
407 		/* Enable TX IRQ only if not already in poll() routine */
408 		if (ctrl & GRETH_RXI)
409 			GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_TXI);
410 		netif_stop_queue(dev);
411 		spin_unlock_irqrestore(&greth->devlock, flags);
412 		return NETDEV_TX_BUSY;
413 	}
414 
415 	if (netif_msg_pktdata(greth))
416 		greth_print_tx_packet(skb);
417 
418 
419 	if (unlikely(skb->len > MAX_FRAME_SIZE)) {
420 		dev->stats.tx_errors++;
421 		goto out;
422 	}
423 
424 	bdp = greth->tx_bd_base + greth->tx_next;
425 	dma_addr = greth_read_bd(&bdp->addr);
426 
427 	memcpy((unsigned char *) phys_to_virt(dma_addr), skb->data, skb->len);
428 
429 	dma_sync_single_for_device(greth->dev, dma_addr, skb->len, DMA_TO_DEVICE);
430 
431 	status = GRETH_BD_EN | GRETH_BD_IE | (skb->len & GRETH_BD_LEN);
432 	greth->tx_bufs_length[greth->tx_next] = skb->len & GRETH_BD_LEN;
433 
434 	/* Wrap around descriptor ring */
435 	if (greth->tx_next == GRETH_TXBD_NUM_MASK) {
436 		status |= GRETH_BD_WR;
437 	}
438 
439 	greth->tx_next = NEXT_TX(greth->tx_next);
440 	greth->tx_free--;
441 
442 	/* Write descriptor control word and enable transmission */
443 	greth_write_bd(&bdp->stat, status);
444 	spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
445 	greth_enable_tx(greth);
446 	spin_unlock_irqrestore(&greth->devlock, flags);
447 
448 out:
449 	dev_kfree_skb(skb);
450 	return err;
451 }
452 
453 static inline u16 greth_num_free_bds(u16 tx_last, u16 tx_next)
454 {
455 	if (tx_next < tx_last)
456 		return (tx_last - tx_next) - 1;
457 	else
458 		return GRETH_TXBD_NUM - (tx_next - tx_last) - 1;
459 }
460 
461 static netdev_tx_t
462 greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
463 {
464 	struct greth_private *greth = netdev_priv(dev);
465 	struct greth_bd *bdp;
466 	u32 status, dma_addr;
467 	int curr_tx, nr_frags, i, err = NETDEV_TX_OK;
468 	unsigned long flags;
469 	u16 tx_last;
470 
471 	nr_frags = skb_shinfo(skb)->nr_frags;
472 	tx_last = greth->tx_last;
473 	rmb(); /* tx_last is updated by the poll task */
474 
475 	if (greth_num_free_bds(tx_last, greth->tx_next) < nr_frags + 1) {
476 		netif_stop_queue(dev);
477 		err = NETDEV_TX_BUSY;
478 		goto out;
479 	}
480 
481 	if (netif_msg_pktdata(greth))
482 		greth_print_tx_packet(skb);
483 
484 	if (unlikely(skb->len > MAX_FRAME_SIZE)) {
485 		dev->stats.tx_errors++;
486 		goto out;
487 	}
488 
489 	/* Save skb pointer. */
490 	greth->tx_skbuff[greth->tx_next] = skb;
491 
492 	/* Linear buf */
493 	if (nr_frags != 0)
494 		status = GRETH_TXBD_MORE;
495 	else
496 		status = GRETH_BD_IE;
497 
498 	if (skb->ip_summed == CHECKSUM_PARTIAL)
499 		status |= GRETH_TXBD_CSALL;
500 	status |= skb_headlen(skb) & GRETH_BD_LEN;
501 	if (greth->tx_next == GRETH_TXBD_NUM_MASK)
502 		status |= GRETH_BD_WR;
503 
504 
505 	bdp = greth->tx_bd_base + greth->tx_next;
506 	greth_write_bd(&bdp->stat, status);
507 	dma_addr = dma_map_single(greth->dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
508 
509 	if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
510 		goto map_error;
511 
512 	greth_write_bd(&bdp->addr, dma_addr);
513 
514 	curr_tx = NEXT_TX(greth->tx_next);
515 
516 	/* Frags */
517 	for (i = 0; i < nr_frags; i++) {
518 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
519 		greth->tx_skbuff[curr_tx] = NULL;
520 		bdp = greth->tx_bd_base + curr_tx;
521 
522 		status = GRETH_BD_EN;
523 		if (skb->ip_summed == CHECKSUM_PARTIAL)
524 			status |= GRETH_TXBD_CSALL;
525 		status |= skb_frag_size(frag) & GRETH_BD_LEN;
526 
527 		/* Wrap around descriptor ring */
528 		if (curr_tx == GRETH_TXBD_NUM_MASK)
529 			status |= GRETH_BD_WR;
530 
531 		/* More fragments left */
532 		if (i < nr_frags - 1)
533 			status |= GRETH_TXBD_MORE;
534 		else
535 			status |= GRETH_BD_IE; /* enable IRQ on last fragment */
536 
537 		greth_write_bd(&bdp->stat, status);
538 
539 		dma_addr = skb_frag_dma_map(greth->dev, frag, 0, skb_frag_size(frag),
540 					    DMA_TO_DEVICE);
541 
542 		if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
543 			goto frag_map_error;
544 
545 		greth_write_bd(&bdp->addr, dma_addr);
546 
547 		curr_tx = NEXT_TX(curr_tx);
548 	}
549 
550 	wmb();
551 
552 	/* Enable the descriptor chain by enabling the first descriptor */
553 	bdp = greth->tx_bd_base + greth->tx_next;
554 	greth_write_bd(&bdp->stat,
555 		       greth_read_bd(&bdp->stat) | GRETH_BD_EN);
556 
557 	spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
558 	greth->tx_next = curr_tx;
559 	greth_enable_tx_and_irq(greth);
560 	spin_unlock_irqrestore(&greth->devlock, flags);
561 
562 	return NETDEV_TX_OK;
563 
564 frag_map_error:
565 	/* Unmap SKB mappings that succeeded and disable descriptor */
566 	for (i = 0; greth->tx_next + i != curr_tx; i++) {
567 		bdp = greth->tx_bd_base + greth->tx_next + i;
568 		dma_unmap_single(greth->dev,
569 				 greth_read_bd(&bdp->addr),
570 				 greth_read_bd(&bdp->stat) & GRETH_BD_LEN,
571 				 DMA_TO_DEVICE);
572 		greth_write_bd(&bdp->stat, 0);
573 	}
574 map_error:
575 	if (net_ratelimit())
576 		dev_warn(greth->dev, "Could not create TX DMA mapping\n");
577 	dev_kfree_skb(skb);
578 out:
579 	return err;
580 }
581 
582 static irqreturn_t greth_interrupt(int irq, void *dev_id)
583 {
584 	struct net_device *dev = dev_id;
585 	struct greth_private *greth;
586 	u32 status, ctrl;
587 	irqreturn_t retval = IRQ_NONE;
588 
589 	greth = netdev_priv(dev);
590 
591 	spin_lock(&greth->devlock);
592 
593 	/* Get the interrupt events that caused us to be here. */
594 	status = GRETH_REGLOAD(greth->regs->status);
595 
596 	/* Must see if interrupts are enabled also, INT_TX|INT_RX flags may be
597 	 * set regardless of whether IRQ is enabled or not. Especially
598 	 * important when shared IRQ.
599 	 */
600 	ctrl = GRETH_REGLOAD(greth->regs->control);
601 
602 	/* Handle rx and tx interrupts through poll */
603 	if (((status & (GRETH_INT_RE | GRETH_INT_RX)) && (ctrl & GRETH_RXI)) ||
604 	    ((status & (GRETH_INT_TE | GRETH_INT_TX)) && (ctrl & GRETH_TXI))) {
605 		retval = IRQ_HANDLED;
606 
607 		/* Disable interrupts and schedule poll() */
608 		greth_disable_irqs(greth);
609 		napi_schedule(&greth->napi);
610 	}
611 
612 	spin_unlock(&greth->devlock);
613 
614 	return retval;
615 }
616 
617 static void greth_clean_tx(struct net_device *dev)
618 {
619 	struct greth_private *greth;
620 	struct greth_bd *bdp;
621 	u32 stat;
622 
623 	greth = netdev_priv(dev);
624 
625 	while (1) {
626 		bdp = greth->tx_bd_base + greth->tx_last;
627 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
628 		mb();
629 		stat = greth_read_bd(&bdp->stat);
630 
631 		if (unlikely(stat & GRETH_BD_EN))
632 			break;
633 
634 		if (greth->tx_free == GRETH_TXBD_NUM)
635 			break;
636 
637 		/* Check status for errors */
638 		if (unlikely(stat & GRETH_TXBD_STATUS)) {
639 			dev->stats.tx_errors++;
640 			if (stat & GRETH_TXBD_ERR_AL)
641 				dev->stats.tx_aborted_errors++;
642 			if (stat & GRETH_TXBD_ERR_UE)
643 				dev->stats.tx_fifo_errors++;
644 		}
645 		dev->stats.tx_packets++;
646 		dev->stats.tx_bytes += greth->tx_bufs_length[greth->tx_last];
647 		greth->tx_last = NEXT_TX(greth->tx_last);
648 		greth->tx_free++;
649 	}
650 
651 	if (greth->tx_free > 0) {
652 		netif_wake_queue(dev);
653 	}
654 }
655 
656 static inline void greth_update_tx_stats(struct net_device *dev, u32 stat)
657 {
658 	/* Check status for errors */
659 	if (unlikely(stat & GRETH_TXBD_STATUS)) {
660 		dev->stats.tx_errors++;
661 		if (stat & GRETH_TXBD_ERR_AL)
662 			dev->stats.tx_aborted_errors++;
663 		if (stat & GRETH_TXBD_ERR_UE)
664 			dev->stats.tx_fifo_errors++;
665 		if (stat & GRETH_TXBD_ERR_LC)
666 			dev->stats.tx_aborted_errors++;
667 	}
668 	dev->stats.tx_packets++;
669 }
670 
671 static void greth_clean_tx_gbit(struct net_device *dev)
672 {
673 	struct greth_private *greth;
674 	struct greth_bd *bdp, *bdp_last_frag;
675 	struct sk_buff *skb = NULL;
676 	u32 stat;
677 	int nr_frags, i;
678 	u16 tx_last;
679 
680 	greth = netdev_priv(dev);
681 	tx_last = greth->tx_last;
682 
683 	while (tx_last != greth->tx_next) {
684 
685 		skb = greth->tx_skbuff[tx_last];
686 
687 		nr_frags = skb_shinfo(skb)->nr_frags;
688 
689 		/* We only clean fully completed SKBs */
690 		bdp_last_frag = greth->tx_bd_base + SKIP_TX(tx_last, nr_frags);
691 
692 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
693 		mb();
694 		stat = greth_read_bd(&bdp_last_frag->stat);
695 
696 		if (stat & GRETH_BD_EN)
697 			break;
698 
699 		greth->tx_skbuff[tx_last] = NULL;
700 
701 		greth_update_tx_stats(dev, stat);
702 		dev->stats.tx_bytes += skb->len;
703 
704 		bdp = greth->tx_bd_base + tx_last;
705 
706 		tx_last = NEXT_TX(tx_last);
707 
708 		dma_unmap_single(greth->dev,
709 				 greth_read_bd(&bdp->addr),
710 				 skb_headlen(skb),
711 				 DMA_TO_DEVICE);
712 
713 		for (i = 0; i < nr_frags; i++) {
714 			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
715 			bdp = greth->tx_bd_base + tx_last;
716 
717 			dma_unmap_page(greth->dev,
718 				       greth_read_bd(&bdp->addr),
719 				       skb_frag_size(frag),
720 				       DMA_TO_DEVICE);
721 
722 			tx_last = NEXT_TX(tx_last);
723 		}
724 		dev_kfree_skb(skb);
725 	}
726 	if (skb) { /* skb is set only if the above while loop was entered */
727 		wmb();
728 		greth->tx_last = tx_last;
729 
730 		if (netif_queue_stopped(dev) &&
731 		    (greth_num_free_bds(tx_last, greth->tx_next) >
732 		    (MAX_SKB_FRAGS+1)))
733 			netif_wake_queue(dev);
734 	}
735 }
736 
737 static int greth_rx(struct net_device *dev, int limit)
738 {
739 	struct greth_private *greth;
740 	struct greth_bd *bdp;
741 	struct sk_buff *skb;
742 	int pkt_len;
743 	int bad, count;
744 	u32 status, dma_addr;
745 	unsigned long flags;
746 
747 	greth = netdev_priv(dev);
748 
749 	for (count = 0; count < limit; ++count) {
750 
751 		bdp = greth->rx_bd_base + greth->rx_cur;
752 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
753 		mb();
754 		status = greth_read_bd(&bdp->stat);
755 
756 		if (unlikely(status & GRETH_BD_EN)) {
757 			break;
758 		}
759 
760 		dma_addr = greth_read_bd(&bdp->addr);
761 		bad = 0;
762 
763 		/* Check status for errors. */
764 		if (unlikely(status & GRETH_RXBD_STATUS)) {
765 			if (status & GRETH_RXBD_ERR_FT) {
766 				dev->stats.rx_length_errors++;
767 				bad = 1;
768 			}
769 			if (status & (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE)) {
770 				dev->stats.rx_frame_errors++;
771 				bad = 1;
772 			}
773 			if (status & GRETH_RXBD_ERR_CRC) {
774 				dev->stats.rx_crc_errors++;
775 				bad = 1;
776 			}
777 		}
778 		if (unlikely(bad)) {
779 			dev->stats.rx_errors++;
780 
781 		} else {
782 
783 			pkt_len = status & GRETH_BD_LEN;
784 
785 			skb = netdev_alloc_skb(dev, pkt_len + NET_IP_ALIGN);
786 
787 			if (unlikely(skb == NULL)) {
788 
789 				if (net_ratelimit())
790 					dev_warn(&dev->dev, "low on memory - " "packet dropped\n");
791 
792 				dev->stats.rx_dropped++;
793 
794 			} else {
795 				skb_reserve(skb, NET_IP_ALIGN);
796 
797 				dma_sync_single_for_cpu(greth->dev,
798 							dma_addr,
799 							pkt_len,
800 							DMA_FROM_DEVICE);
801 
802 				if (netif_msg_pktdata(greth))
803 					greth_print_rx_packet(phys_to_virt(dma_addr), pkt_len);
804 
805 				skb_put_data(skb, phys_to_virt(dma_addr),
806 					     pkt_len);
807 
808 				skb->protocol = eth_type_trans(skb, dev);
809 				dev->stats.rx_bytes += pkt_len;
810 				dev->stats.rx_packets++;
811 				netif_receive_skb(skb);
812 			}
813 		}
814 
815 		status = GRETH_BD_EN | GRETH_BD_IE;
816 		if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
817 			status |= GRETH_BD_WR;
818 		}
819 
820 		wmb();
821 		greth_write_bd(&bdp->stat, status);
822 
823 		dma_sync_single_for_device(greth->dev, dma_addr, MAX_FRAME_SIZE, DMA_FROM_DEVICE);
824 
825 		spin_lock_irqsave(&greth->devlock, flags); /* save from XMIT */
826 		greth_enable_rx(greth);
827 		spin_unlock_irqrestore(&greth->devlock, flags);
828 
829 		greth->rx_cur = NEXT_RX(greth->rx_cur);
830 	}
831 
832 	return count;
833 }
834 
835 static inline int hw_checksummed(u32 status)
836 {
837 
838 	if (status & GRETH_RXBD_IP_FRAG)
839 		return 0;
840 
841 	if (status & GRETH_RXBD_IP && status & GRETH_RXBD_IP_CSERR)
842 		return 0;
843 
844 	if (status & GRETH_RXBD_UDP && status & GRETH_RXBD_UDP_CSERR)
845 		return 0;
846 
847 	if (status & GRETH_RXBD_TCP && status & GRETH_RXBD_TCP_CSERR)
848 		return 0;
849 
850 	return 1;
851 }
852 
853 static int greth_rx_gbit(struct net_device *dev, int limit)
854 {
855 	struct greth_private *greth;
856 	struct greth_bd *bdp;
857 	struct sk_buff *skb, *newskb;
858 	int pkt_len;
859 	int bad, count = 0;
860 	u32 status, dma_addr;
861 	unsigned long flags;
862 
863 	greth = netdev_priv(dev);
864 
865 	for (count = 0; count < limit; ++count) {
866 
867 		bdp = greth->rx_bd_base + greth->rx_cur;
868 		skb = greth->rx_skbuff[greth->rx_cur];
869 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
870 		mb();
871 		status = greth_read_bd(&bdp->stat);
872 		bad = 0;
873 
874 		if (status & GRETH_BD_EN)
875 			break;
876 
877 		/* Check status for errors. */
878 		if (unlikely(status & GRETH_RXBD_STATUS)) {
879 
880 			if (status & GRETH_RXBD_ERR_FT) {
881 				dev->stats.rx_length_errors++;
882 				bad = 1;
883 			} else if (status &
884 				   (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE | GRETH_RXBD_ERR_LE)) {
885 				dev->stats.rx_frame_errors++;
886 				bad = 1;
887 			} else if (status & GRETH_RXBD_ERR_CRC) {
888 				dev->stats.rx_crc_errors++;
889 				bad = 1;
890 			}
891 		}
892 
893 		/* Allocate new skb to replace current, not needed if the
894 		 * current skb can be reused */
895 		if (!bad && (newskb=netdev_alloc_skb(dev, MAX_FRAME_SIZE + NET_IP_ALIGN))) {
896 			skb_reserve(newskb, NET_IP_ALIGN);
897 
898 			dma_addr = dma_map_single(greth->dev,
899 						      newskb->data,
900 						      MAX_FRAME_SIZE + NET_IP_ALIGN,
901 						      DMA_FROM_DEVICE);
902 
903 			if (!dma_mapping_error(greth->dev, dma_addr)) {
904 				/* Process the incoming frame. */
905 				pkt_len = status & GRETH_BD_LEN;
906 
907 				dma_unmap_single(greth->dev,
908 						 greth_read_bd(&bdp->addr),
909 						 MAX_FRAME_SIZE + NET_IP_ALIGN,
910 						 DMA_FROM_DEVICE);
911 
912 				if (netif_msg_pktdata(greth))
913 					greth_print_rx_packet(phys_to_virt(greth_read_bd(&bdp->addr)), pkt_len);
914 
915 				skb_put(skb, pkt_len);
916 
917 				if (dev->features & NETIF_F_RXCSUM && hw_checksummed(status))
918 					skb->ip_summed = CHECKSUM_UNNECESSARY;
919 				else
920 					skb_checksum_none_assert(skb);
921 
922 				skb->protocol = eth_type_trans(skb, dev);
923 				dev->stats.rx_packets++;
924 				dev->stats.rx_bytes += pkt_len;
925 				netif_receive_skb(skb);
926 
927 				greth->rx_skbuff[greth->rx_cur] = newskb;
928 				greth_write_bd(&bdp->addr, dma_addr);
929 			} else {
930 				if (net_ratelimit())
931 					dev_warn(greth->dev, "Could not create DMA mapping, dropping packet\n");
932 				dev_kfree_skb(newskb);
933 				/* reusing current skb, so it is a drop */
934 				dev->stats.rx_dropped++;
935 			}
936 		} else if (bad) {
937 			/* Bad Frame transfer, the skb is reused */
938 			dev->stats.rx_dropped++;
939 		} else {
940 			/* Failed Allocating a new skb. This is rather stupid
941 			 * but the current "filled" skb is reused, as if
942 			 * transfer failure. One could argue that RX descriptor
943 			 * table handling should be divided into cleaning and
944 			 * filling as the TX part of the driver
945 			 */
946 			if (net_ratelimit())
947 				dev_warn(greth->dev, "Could not allocate SKB, dropping packet\n");
948 			/* reusing current skb, so it is a drop */
949 			dev->stats.rx_dropped++;
950 		}
951 
952 		status = GRETH_BD_EN | GRETH_BD_IE;
953 		if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
954 			status |= GRETH_BD_WR;
955 		}
956 
957 		wmb();
958 		greth_write_bd(&bdp->stat, status);
959 		spin_lock_irqsave(&greth->devlock, flags);
960 		greth_enable_rx(greth);
961 		spin_unlock_irqrestore(&greth->devlock, flags);
962 		greth->rx_cur = NEXT_RX(greth->rx_cur);
963 	}
964 
965 	return count;
966 
967 }
968 
969 static int greth_poll(struct napi_struct *napi, int budget)
970 {
971 	struct greth_private *greth;
972 	int work_done = 0;
973 	unsigned long flags;
974 	u32 mask, ctrl;
975 	greth = container_of(napi, struct greth_private, napi);
976 
977 restart_txrx_poll:
978 	if (greth->gbit_mac) {
979 		greth_clean_tx_gbit(greth->netdev);
980 		work_done += greth_rx_gbit(greth->netdev, budget - work_done);
981 	} else {
982 		if (netif_queue_stopped(greth->netdev))
983 			greth_clean_tx(greth->netdev);
984 		work_done += greth_rx(greth->netdev, budget - work_done);
985 	}
986 
987 	if (work_done < budget) {
988 
989 		spin_lock_irqsave(&greth->devlock, flags);
990 
991 		ctrl = GRETH_REGLOAD(greth->regs->control);
992 		if ((greth->gbit_mac && (greth->tx_last != greth->tx_next)) ||
993 		    (!greth->gbit_mac && netif_queue_stopped(greth->netdev))) {
994 			GRETH_REGSAVE(greth->regs->control,
995 					ctrl | GRETH_TXI | GRETH_RXI);
996 			mask = GRETH_INT_RX | GRETH_INT_RE |
997 			       GRETH_INT_TX | GRETH_INT_TE;
998 		} else {
999 			GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_RXI);
1000 			mask = GRETH_INT_RX | GRETH_INT_RE;
1001 		}
1002 
1003 		if (GRETH_REGLOAD(greth->regs->status) & mask) {
1004 			GRETH_REGSAVE(greth->regs->control, ctrl);
1005 			spin_unlock_irqrestore(&greth->devlock, flags);
1006 			goto restart_txrx_poll;
1007 		} else {
1008 			napi_complete_done(napi, work_done);
1009 			spin_unlock_irqrestore(&greth->devlock, flags);
1010 		}
1011 	}
1012 
1013 	return work_done;
1014 }
1015 
1016 static int greth_set_mac_add(struct net_device *dev, void *p)
1017 {
1018 	struct sockaddr *addr = p;
1019 	struct greth_private *greth;
1020 	struct greth_regs *regs;
1021 
1022 	greth = netdev_priv(dev);
1023 	regs = greth->regs;
1024 
1025 	if (!is_valid_ether_addr(addr->sa_data))
1026 		return -EADDRNOTAVAIL;
1027 
1028 	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
1029 	GRETH_REGSAVE(regs->esa_msb, dev->dev_addr[0] << 8 | dev->dev_addr[1]);
1030 	GRETH_REGSAVE(regs->esa_lsb, dev->dev_addr[2] << 24 | dev->dev_addr[3] << 16 |
1031 		      dev->dev_addr[4] << 8 | dev->dev_addr[5]);
1032 
1033 	return 0;
1034 }
1035 
1036 static u32 greth_hash_get_index(__u8 *addr)
1037 {
1038 	return (ether_crc(6, addr)) & 0x3F;
1039 }
1040 
1041 static void greth_set_hash_filter(struct net_device *dev)
1042 {
1043 	struct netdev_hw_addr *ha;
1044 	struct greth_private *greth = netdev_priv(dev);
1045 	struct greth_regs *regs = greth->regs;
1046 	u32 mc_filter[2];
1047 	unsigned int bitnr;
1048 
1049 	mc_filter[0] = mc_filter[1] = 0;
1050 
1051 	netdev_for_each_mc_addr(ha, dev) {
1052 		bitnr = greth_hash_get_index(ha->addr);
1053 		mc_filter[bitnr >> 5] |= 1 << (bitnr & 31);
1054 	}
1055 
1056 	GRETH_REGSAVE(regs->hash_msb, mc_filter[1]);
1057 	GRETH_REGSAVE(regs->hash_lsb, mc_filter[0]);
1058 }
1059 
1060 static void greth_set_multicast_list(struct net_device *dev)
1061 {
1062 	int cfg;
1063 	struct greth_private *greth = netdev_priv(dev);
1064 	struct greth_regs *regs = greth->regs;
1065 
1066 	cfg = GRETH_REGLOAD(regs->control);
1067 	if (dev->flags & IFF_PROMISC)
1068 		cfg |= GRETH_CTRL_PR;
1069 	else
1070 		cfg &= ~GRETH_CTRL_PR;
1071 
1072 	if (greth->multicast) {
1073 		if (dev->flags & IFF_ALLMULTI) {
1074 			GRETH_REGSAVE(regs->hash_msb, -1);
1075 			GRETH_REGSAVE(regs->hash_lsb, -1);
1076 			cfg |= GRETH_CTRL_MCEN;
1077 			GRETH_REGSAVE(regs->control, cfg);
1078 			return;
1079 		}
1080 
1081 		if (netdev_mc_empty(dev)) {
1082 			cfg &= ~GRETH_CTRL_MCEN;
1083 			GRETH_REGSAVE(regs->control, cfg);
1084 			return;
1085 		}
1086 
1087 		/* Setup multicast filter */
1088 		greth_set_hash_filter(dev);
1089 		cfg |= GRETH_CTRL_MCEN;
1090 	}
1091 	GRETH_REGSAVE(regs->control, cfg);
1092 }
1093 
1094 static u32 greth_get_msglevel(struct net_device *dev)
1095 {
1096 	struct greth_private *greth = netdev_priv(dev);
1097 	return greth->msg_enable;
1098 }
1099 
1100 static void greth_set_msglevel(struct net_device *dev, u32 value)
1101 {
1102 	struct greth_private *greth = netdev_priv(dev);
1103 	greth->msg_enable = value;
1104 }
1105 
1106 static int greth_get_regs_len(struct net_device *dev)
1107 {
1108 	return sizeof(struct greth_regs);
1109 }
1110 
1111 static void greth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1112 {
1113 	struct greth_private *greth = netdev_priv(dev);
1114 
1115 	strlcpy(info->driver, dev_driver_string(greth->dev),
1116 		sizeof(info->driver));
1117 	strlcpy(info->version, "revision: 1.0", sizeof(info->version));
1118 	strlcpy(info->bus_info, greth->dev->bus->name, sizeof(info->bus_info));
1119 	strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
1120 }
1121 
1122 static void greth_get_regs(struct net_device *dev, struct ethtool_regs *regs, void *p)
1123 {
1124 	int i;
1125 	struct greth_private *greth = netdev_priv(dev);
1126 	u32 __iomem *greth_regs = (u32 __iomem *) greth->regs;
1127 	u32 *buff = p;
1128 
1129 	for (i = 0; i < sizeof(struct greth_regs) / sizeof(u32); i++)
1130 		buff[i] = greth_read_bd(&greth_regs[i]);
1131 }
1132 
1133 static const struct ethtool_ops greth_ethtool_ops = {
1134 	.get_msglevel		= greth_get_msglevel,
1135 	.set_msglevel		= greth_set_msglevel,
1136 	.get_drvinfo		= greth_get_drvinfo,
1137 	.get_regs_len           = greth_get_regs_len,
1138 	.get_regs               = greth_get_regs,
1139 	.get_link		= ethtool_op_get_link,
1140 	.get_link_ksettings	= phy_ethtool_get_link_ksettings,
1141 	.set_link_ksettings	= phy_ethtool_set_link_ksettings,
1142 };
1143 
1144 static struct net_device_ops greth_netdev_ops = {
1145 	.ndo_open		= greth_open,
1146 	.ndo_stop		= greth_close,
1147 	.ndo_start_xmit		= greth_start_xmit,
1148 	.ndo_set_mac_address	= greth_set_mac_add,
1149 	.ndo_validate_addr	= eth_validate_addr,
1150 };
1151 
1152 static inline int wait_for_mdio(struct greth_private *greth)
1153 {
1154 	unsigned long timeout = jiffies + 4*HZ/100;
1155 	while (GRETH_REGLOAD(greth->regs->mdio) & GRETH_MII_BUSY) {
1156 		if (time_after(jiffies, timeout))
1157 			return 0;
1158 	}
1159 	return 1;
1160 }
1161 
1162 static int greth_mdio_read(struct mii_bus *bus, int phy, int reg)
1163 {
1164 	struct greth_private *greth = bus->priv;
1165 	int data;
1166 
1167 	if (!wait_for_mdio(greth))
1168 		return -EBUSY;
1169 
1170 	GRETH_REGSAVE(greth->regs->mdio, ((phy & 0x1F) << 11) | ((reg & 0x1F) << 6) | 2);
1171 
1172 	if (!wait_for_mdio(greth))
1173 		return -EBUSY;
1174 
1175 	if (!(GRETH_REGLOAD(greth->regs->mdio) & GRETH_MII_NVALID)) {
1176 		data = (GRETH_REGLOAD(greth->regs->mdio) >> 16) & 0xFFFF;
1177 		return data;
1178 
1179 	} else {
1180 		return -1;
1181 	}
1182 }
1183 
1184 static int greth_mdio_write(struct mii_bus *bus, int phy, int reg, u16 val)
1185 {
1186 	struct greth_private *greth = bus->priv;
1187 
1188 	if (!wait_for_mdio(greth))
1189 		return -EBUSY;
1190 
1191 	GRETH_REGSAVE(greth->regs->mdio,
1192 		      ((val & 0xFFFF) << 16) | ((phy & 0x1F) << 11) | ((reg & 0x1F) << 6) | 1);
1193 
1194 	if (!wait_for_mdio(greth))
1195 		return -EBUSY;
1196 
1197 	return 0;
1198 }
1199 
1200 static void greth_link_change(struct net_device *dev)
1201 {
1202 	struct greth_private *greth = netdev_priv(dev);
1203 	struct phy_device *phydev = dev->phydev;
1204 	unsigned long flags;
1205 	int status_change = 0;
1206 	u32 ctrl;
1207 
1208 	spin_lock_irqsave(&greth->devlock, flags);
1209 
1210 	if (phydev->link) {
1211 
1212 		if ((greth->speed != phydev->speed) || (greth->duplex != phydev->duplex)) {
1213 			ctrl = GRETH_REGLOAD(greth->regs->control) &
1214 			       ~(GRETH_CTRL_FD | GRETH_CTRL_SP | GRETH_CTRL_GB);
1215 
1216 			if (phydev->duplex)
1217 				ctrl |= GRETH_CTRL_FD;
1218 
1219 			if (phydev->speed == SPEED_100)
1220 				ctrl |= GRETH_CTRL_SP;
1221 			else if (phydev->speed == SPEED_1000)
1222 				ctrl |= GRETH_CTRL_GB;
1223 
1224 			GRETH_REGSAVE(greth->regs->control, ctrl);
1225 			greth->speed = phydev->speed;
1226 			greth->duplex = phydev->duplex;
1227 			status_change = 1;
1228 		}
1229 	}
1230 
1231 	if (phydev->link != greth->link) {
1232 		if (!phydev->link) {
1233 			greth->speed = 0;
1234 			greth->duplex = -1;
1235 		}
1236 		greth->link = phydev->link;
1237 
1238 		status_change = 1;
1239 	}
1240 
1241 	spin_unlock_irqrestore(&greth->devlock, flags);
1242 
1243 	if (status_change) {
1244 		if (phydev->link)
1245 			pr_debug("%s: link up (%d/%s)\n",
1246 				dev->name, phydev->speed,
1247 				DUPLEX_FULL == phydev->duplex ? "Full" : "Half");
1248 		else
1249 			pr_debug("%s: link down\n", dev->name);
1250 	}
1251 }
1252 
1253 static int greth_mdio_probe(struct net_device *dev)
1254 {
1255 	struct greth_private *greth = netdev_priv(dev);
1256 	struct phy_device *phy = NULL;
1257 	int ret;
1258 
1259 	/* Find the first PHY */
1260 	phy = phy_find_first(greth->mdio);
1261 
1262 	if (!phy) {
1263 		if (netif_msg_probe(greth))
1264 			dev_err(&dev->dev, "no PHY found\n");
1265 		return -ENXIO;
1266 	}
1267 
1268 	ret = phy_connect_direct(dev, phy, &greth_link_change,
1269 				 greth->gbit_mac ? PHY_INTERFACE_MODE_GMII : PHY_INTERFACE_MODE_MII);
1270 	if (ret) {
1271 		if (netif_msg_ifup(greth))
1272 			dev_err(&dev->dev, "could not attach to PHY\n");
1273 		return ret;
1274 	}
1275 
1276 	if (greth->gbit_mac)
1277 		phy_set_max_speed(phy, SPEED_1000);
1278 	else
1279 		phy_set_max_speed(phy, SPEED_100);
1280 
1281 	linkmode_copy(phy->advertising, phy->supported);
1282 
1283 	greth->link = 0;
1284 	greth->speed = 0;
1285 	greth->duplex = -1;
1286 
1287 	return 0;
1288 }
1289 
1290 static int greth_mdio_init(struct greth_private *greth)
1291 {
1292 	int ret;
1293 	unsigned long timeout;
1294 	struct net_device *ndev = greth->netdev;
1295 
1296 	greth->mdio = mdiobus_alloc();
1297 	if (!greth->mdio) {
1298 		return -ENOMEM;
1299 	}
1300 
1301 	greth->mdio->name = "greth-mdio";
1302 	snprintf(greth->mdio->id, MII_BUS_ID_SIZE, "%s-%d", greth->mdio->name, greth->irq);
1303 	greth->mdio->read = greth_mdio_read;
1304 	greth->mdio->write = greth_mdio_write;
1305 	greth->mdio->priv = greth;
1306 
1307 	ret = mdiobus_register(greth->mdio);
1308 	if (ret) {
1309 		goto error;
1310 	}
1311 
1312 	ret = greth_mdio_probe(greth->netdev);
1313 	if (ret) {
1314 		if (netif_msg_probe(greth))
1315 			dev_err(&greth->netdev->dev, "failed to probe MDIO bus\n");
1316 		goto unreg_mdio;
1317 	}
1318 
1319 	phy_start(ndev->phydev);
1320 
1321 	/* If Ethernet debug link is used make autoneg happen right away */
1322 	if (greth->edcl && greth_edcl == 1) {
1323 		phy_start_aneg(ndev->phydev);
1324 		timeout = jiffies + 6*HZ;
1325 		while (!phy_aneg_done(ndev->phydev) &&
1326 		       time_before(jiffies, timeout)) {
1327 		}
1328 		phy_read_status(ndev->phydev);
1329 		greth_link_change(greth->netdev);
1330 	}
1331 
1332 	return 0;
1333 
1334 unreg_mdio:
1335 	mdiobus_unregister(greth->mdio);
1336 error:
1337 	mdiobus_free(greth->mdio);
1338 	return ret;
1339 }
1340 
1341 /* Initialize the GRETH MAC */
1342 static int greth_of_probe(struct platform_device *ofdev)
1343 {
1344 	struct net_device *dev;
1345 	struct greth_private *greth;
1346 	struct greth_regs *regs;
1347 
1348 	int i;
1349 	int err;
1350 	int tmp;
1351 	unsigned long timeout;
1352 
1353 	dev = alloc_etherdev(sizeof(struct greth_private));
1354 
1355 	if (dev == NULL)
1356 		return -ENOMEM;
1357 
1358 	greth = netdev_priv(dev);
1359 	greth->netdev = dev;
1360 	greth->dev = &ofdev->dev;
1361 
1362 	if (greth_debug > 0)
1363 		greth->msg_enable = greth_debug;
1364 	else
1365 		greth->msg_enable = GRETH_DEF_MSG_ENABLE;
1366 
1367 	spin_lock_init(&greth->devlock);
1368 
1369 	greth->regs = of_ioremap(&ofdev->resource[0], 0,
1370 				 resource_size(&ofdev->resource[0]),
1371 				 "grlib-greth regs");
1372 
1373 	if (greth->regs == NULL) {
1374 		if (netif_msg_probe(greth))
1375 			dev_err(greth->dev, "ioremap failure.\n");
1376 		err = -EIO;
1377 		goto error1;
1378 	}
1379 
1380 	regs = greth->regs;
1381 	greth->irq = ofdev->archdata.irqs[0];
1382 
1383 	dev_set_drvdata(greth->dev, dev);
1384 	SET_NETDEV_DEV(dev, greth->dev);
1385 
1386 	if (netif_msg_probe(greth))
1387 		dev_dbg(greth->dev, "resetting controller.\n");
1388 
1389 	/* Reset the controller. */
1390 	GRETH_REGSAVE(regs->control, GRETH_RESET);
1391 
1392 	/* Wait for MAC to reset itself */
1393 	timeout = jiffies + HZ/100;
1394 	while (GRETH_REGLOAD(regs->control) & GRETH_RESET) {
1395 		if (time_after(jiffies, timeout)) {
1396 			err = -EIO;
1397 			if (netif_msg_probe(greth))
1398 				dev_err(greth->dev, "timeout when waiting for reset.\n");
1399 			goto error2;
1400 		}
1401 	}
1402 
1403 	/* Get default PHY address  */
1404 	greth->phyaddr = (GRETH_REGLOAD(regs->mdio) >> 11) & 0x1F;
1405 
1406 	/* Check if we have GBIT capable MAC */
1407 	tmp = GRETH_REGLOAD(regs->control);
1408 	greth->gbit_mac = (tmp >> 27) & 1;
1409 
1410 	/* Check for multicast capability */
1411 	greth->multicast = (tmp >> 25) & 1;
1412 
1413 	greth->edcl = (tmp >> 31) & 1;
1414 
1415 	/* If we have EDCL we disable the EDCL speed-duplex FSM so
1416 	 * it doesn't interfere with the software */
1417 	if (greth->edcl != 0)
1418 		GRETH_REGORIN(regs->control, GRETH_CTRL_DISDUPLEX);
1419 
1420 	/* Check if MAC can handle MDIO interrupts */
1421 	greth->mdio_int_en = (tmp >> 26) & 1;
1422 
1423 	err = greth_mdio_init(greth);
1424 	if (err) {
1425 		if (netif_msg_probe(greth))
1426 			dev_err(greth->dev, "failed to register MDIO bus\n");
1427 		goto error2;
1428 	}
1429 
1430 	/* Allocate TX descriptor ring in coherent memory */
1431 	greth->tx_bd_base = dma_alloc_coherent(greth->dev, 1024,
1432 					       &greth->tx_bd_base_phys,
1433 					       GFP_KERNEL);
1434 	if (!greth->tx_bd_base) {
1435 		err = -ENOMEM;
1436 		goto error3;
1437 	}
1438 
1439 	/* Allocate RX descriptor ring in coherent memory */
1440 	greth->rx_bd_base = dma_alloc_coherent(greth->dev, 1024,
1441 					       &greth->rx_bd_base_phys,
1442 					       GFP_KERNEL);
1443 	if (!greth->rx_bd_base) {
1444 		err = -ENOMEM;
1445 		goto error4;
1446 	}
1447 
1448 	/* Get MAC address from: module param, OF property or ID prom */
1449 	for (i = 0; i < 6; i++) {
1450 		if (macaddr[i] != 0)
1451 			break;
1452 	}
1453 	if (i == 6) {
1454 		const u8 *addr;
1455 
1456 		addr = of_get_mac_address(ofdev->dev.of_node);
1457 		if (!IS_ERR(addr)) {
1458 			for (i = 0; i < 6; i++)
1459 				macaddr[i] = (unsigned int) addr[i];
1460 		} else {
1461 #ifdef CONFIG_SPARC
1462 			for (i = 0; i < 6; i++)
1463 				macaddr[i] = (unsigned int) idprom->id_ethaddr[i];
1464 #endif
1465 		}
1466 	}
1467 
1468 	for (i = 0; i < 6; i++)
1469 		dev->dev_addr[i] = macaddr[i];
1470 
1471 	macaddr[5]++;
1472 
1473 	if (!is_valid_ether_addr(&dev->dev_addr[0])) {
1474 		if (netif_msg_probe(greth))
1475 			dev_err(greth->dev, "no valid ethernet address, aborting.\n");
1476 		err = -EINVAL;
1477 		goto error5;
1478 	}
1479 
1480 	GRETH_REGSAVE(regs->esa_msb, dev->dev_addr[0] << 8 | dev->dev_addr[1]);
1481 	GRETH_REGSAVE(regs->esa_lsb, dev->dev_addr[2] << 24 | dev->dev_addr[3] << 16 |
1482 		      dev->dev_addr[4] << 8 | dev->dev_addr[5]);
1483 
1484 	/* Clear all pending interrupts except PHY irq */
1485 	GRETH_REGSAVE(regs->status, 0xFF);
1486 
1487 	if (greth->gbit_mac) {
1488 		dev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM |
1489 			NETIF_F_RXCSUM;
1490 		dev->features = dev->hw_features | NETIF_F_HIGHDMA;
1491 		greth_netdev_ops.ndo_start_xmit = greth_start_xmit_gbit;
1492 	}
1493 
1494 	if (greth->multicast) {
1495 		greth_netdev_ops.ndo_set_rx_mode = greth_set_multicast_list;
1496 		dev->flags |= IFF_MULTICAST;
1497 	} else {
1498 		dev->flags &= ~IFF_MULTICAST;
1499 	}
1500 
1501 	dev->netdev_ops = &greth_netdev_ops;
1502 	dev->ethtool_ops = &greth_ethtool_ops;
1503 
1504 	err = register_netdev(dev);
1505 	if (err) {
1506 		if (netif_msg_probe(greth))
1507 			dev_err(greth->dev, "netdevice registration failed.\n");
1508 		goto error5;
1509 	}
1510 
1511 	/* setup NAPI */
1512 	netif_napi_add(dev, &greth->napi, greth_poll, 64);
1513 
1514 	return 0;
1515 
1516 error5:
1517 	dma_free_coherent(greth->dev, 1024, greth->rx_bd_base, greth->rx_bd_base_phys);
1518 error4:
1519 	dma_free_coherent(greth->dev, 1024, greth->tx_bd_base, greth->tx_bd_base_phys);
1520 error3:
1521 	mdiobus_unregister(greth->mdio);
1522 error2:
1523 	of_iounmap(&ofdev->resource[0], greth->regs, resource_size(&ofdev->resource[0]));
1524 error1:
1525 	free_netdev(dev);
1526 	return err;
1527 }
1528 
1529 static int greth_of_remove(struct platform_device *of_dev)
1530 {
1531 	struct net_device *ndev = platform_get_drvdata(of_dev);
1532 	struct greth_private *greth = netdev_priv(ndev);
1533 
1534 	/* Free descriptor areas */
1535 	dma_free_coherent(&of_dev->dev, 1024, greth->rx_bd_base, greth->rx_bd_base_phys);
1536 
1537 	dma_free_coherent(&of_dev->dev, 1024, greth->tx_bd_base, greth->tx_bd_base_phys);
1538 
1539 	if (ndev->phydev)
1540 		phy_stop(ndev->phydev);
1541 	mdiobus_unregister(greth->mdio);
1542 
1543 	unregister_netdev(ndev);
1544 	free_netdev(ndev);
1545 
1546 	of_iounmap(&of_dev->resource[0], greth->regs, resource_size(&of_dev->resource[0]));
1547 
1548 	return 0;
1549 }
1550 
1551 static const struct of_device_id greth_of_match[] = {
1552 	{
1553 	 .name = "GAISLER_ETHMAC",
1554 	 },
1555 	{
1556 	 .name = "01_01d",
1557 	 },
1558 	{},
1559 };
1560 
1561 MODULE_DEVICE_TABLE(of, greth_of_match);
1562 
1563 static struct platform_driver greth_of_driver = {
1564 	.driver = {
1565 		.name = "grlib-greth",
1566 		.of_match_table = greth_of_match,
1567 	},
1568 	.probe = greth_of_probe,
1569 	.remove = greth_of_remove,
1570 };
1571 
1572 module_platform_driver(greth_of_driver);
1573 
1574 MODULE_AUTHOR("Aeroflex Gaisler AB.");
1575 MODULE_DESCRIPTION("Aeroflex Gaisler Ethernet MAC driver");
1576 MODULE_LICENSE("GPL");
1577