xref: /linux/drivers/net/ethernet/aeroflex/greth.c (revision 561add0da6d3d07c9bccb0832fb6ed5619167d26)
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  * https://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.h>
33 #include <linux/of_net.h>
34 #include <linux/platform_device.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 				dev_kfree_skb(skb);
262 				goto cleanup;
263 			}
264 			greth->rx_skbuff[i] = skb;
265 			greth_write_bd(&rx_bd[i].addr, dma_addr);
266 			greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
267 		}
268 
269 	} else {
270 
271 		/* 10/100 MAC uses a fixed set of buffers and copy to/from SKBs */
272 		for (i = 0; i < GRETH_RXBD_NUM; i++) {
273 
274 			greth->rx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);
275 
276 			if (greth->rx_bufs[i] == NULL) {
277 				if (netif_msg_ifup(greth))
278 					dev_err(greth->dev, "Error allocating DMA ring.\n");
279 				goto cleanup;
280 			}
281 
282 			dma_addr = dma_map_single(greth->dev,
283 						  greth->rx_bufs[i],
284 						  MAX_FRAME_SIZE,
285 						  DMA_FROM_DEVICE);
286 
287 			if (dma_mapping_error(greth->dev, dma_addr)) {
288 				if (netif_msg_ifup(greth))
289 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
290 				goto cleanup;
291 			}
292 			greth_write_bd(&rx_bd[i].addr, dma_addr);
293 			greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
294 		}
295 		for (i = 0; i < GRETH_TXBD_NUM; i++) {
296 
297 			greth->tx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);
298 
299 			if (greth->tx_bufs[i] == NULL) {
300 				if (netif_msg_ifup(greth))
301 					dev_err(greth->dev, "Error allocating DMA ring.\n");
302 				goto cleanup;
303 			}
304 
305 			dma_addr = dma_map_single(greth->dev,
306 						  greth->tx_bufs[i],
307 						  MAX_FRAME_SIZE,
308 						  DMA_TO_DEVICE);
309 
310 			if (dma_mapping_error(greth->dev, dma_addr)) {
311 				if (netif_msg_ifup(greth))
312 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
313 				goto cleanup;
314 			}
315 			greth_write_bd(&tx_bd[i].addr, dma_addr);
316 			greth_write_bd(&tx_bd[i].stat, 0);
317 		}
318 	}
319 	greth_write_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat,
320 		       greth_read_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat) | GRETH_BD_WR);
321 
322 	/* Initialize pointers. */
323 	greth->rx_cur = 0;
324 	greth->tx_next = 0;
325 	greth->tx_last = 0;
326 	greth->tx_free = GRETH_TXBD_NUM;
327 
328 	/* Initialize descriptor base address */
329 	GRETH_REGSAVE(greth->regs->tx_desc_p, greth->tx_bd_base_phys);
330 	GRETH_REGSAVE(greth->regs->rx_desc_p, greth->rx_bd_base_phys);
331 
332 	return 0;
333 
334 cleanup:
335 	greth_clean_rings(greth);
336 	return -ENOMEM;
337 }
338 
339 static int greth_open(struct net_device *dev)
340 {
341 	struct greth_private *greth = netdev_priv(dev);
342 	int err;
343 
344 	err = greth_init_rings(greth);
345 	if (err) {
346 		if (netif_msg_ifup(greth))
347 			dev_err(&dev->dev, "Could not allocate memory for DMA rings\n");
348 		return err;
349 	}
350 
351 	err = request_irq(greth->irq, greth_interrupt, 0, "eth", (void *) dev);
352 	if (err) {
353 		if (netif_msg_ifup(greth))
354 			dev_err(&dev->dev, "Could not allocate interrupt %d\n", dev->irq);
355 		greth_clean_rings(greth);
356 		return err;
357 	}
358 
359 	if (netif_msg_ifup(greth))
360 		dev_dbg(&dev->dev, " starting queue\n");
361 	netif_start_queue(dev);
362 
363 	GRETH_REGSAVE(greth->regs->status, 0xFF);
364 
365 	napi_enable(&greth->napi);
366 
367 	greth_enable_irqs(greth);
368 	greth_enable_tx(greth);
369 	greth_enable_rx(greth);
370 	return 0;
371 
372 }
373 
374 static int greth_close(struct net_device *dev)
375 {
376 	struct greth_private *greth = netdev_priv(dev);
377 
378 	napi_disable(&greth->napi);
379 
380 	greth_disable_irqs(greth);
381 	greth_disable_tx(greth);
382 	greth_disable_rx(greth);
383 
384 	netif_stop_queue(dev);
385 
386 	free_irq(greth->irq, (void *) dev);
387 
388 	greth_clean_rings(greth);
389 
390 	return 0;
391 }
392 
393 static netdev_tx_t
394 greth_start_xmit(struct sk_buff *skb, struct net_device *dev)
395 {
396 	struct greth_private *greth = netdev_priv(dev);
397 	struct greth_bd *bdp;
398 	int err = NETDEV_TX_OK;
399 	u32 status, dma_addr, ctrl;
400 	unsigned long flags;
401 
402 	/* Clean TX Ring */
403 	greth_clean_tx(greth->netdev);
404 
405 	if (unlikely(greth->tx_free <= 0)) {
406 		spin_lock_irqsave(&greth->devlock, flags);/*save from poll/irq*/
407 		ctrl = GRETH_REGLOAD(greth->regs->control);
408 		/* Enable TX IRQ only if not already in poll() routine */
409 		if (ctrl & GRETH_RXI)
410 			GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_TXI);
411 		netif_stop_queue(dev);
412 		spin_unlock_irqrestore(&greth->devlock, flags);
413 		return NETDEV_TX_BUSY;
414 	}
415 
416 	if (netif_msg_pktdata(greth))
417 		greth_print_tx_packet(skb);
418 
419 
420 	if (unlikely(skb->len > MAX_FRAME_SIZE)) {
421 		dev->stats.tx_errors++;
422 		goto out;
423 	}
424 
425 	bdp = greth->tx_bd_base + greth->tx_next;
426 	dma_addr = greth_read_bd(&bdp->addr);
427 
428 	memcpy((unsigned char *) phys_to_virt(dma_addr), skb->data, skb->len);
429 
430 	dma_sync_single_for_device(greth->dev, dma_addr, skb->len, DMA_TO_DEVICE);
431 
432 	status = GRETH_BD_EN | GRETH_BD_IE | (skb->len & GRETH_BD_LEN);
433 	greth->tx_bufs_length[greth->tx_next] = skb->len & GRETH_BD_LEN;
434 
435 	/* Wrap around descriptor ring */
436 	if (greth->tx_next == GRETH_TXBD_NUM_MASK) {
437 		status |= GRETH_BD_WR;
438 	}
439 
440 	greth->tx_next = NEXT_TX(greth->tx_next);
441 	greth->tx_free--;
442 
443 	/* Write descriptor control word and enable transmission */
444 	greth_write_bd(&bdp->stat, status);
445 	spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
446 	greth_enable_tx(greth);
447 	spin_unlock_irqrestore(&greth->devlock, flags);
448 
449 out:
450 	dev_kfree_skb(skb);
451 	return err;
452 }
453 
454 static inline u16 greth_num_free_bds(u16 tx_last, u16 tx_next)
455 {
456 	if (tx_next < tx_last)
457 		return (tx_last - tx_next) - 1;
458 	else
459 		return GRETH_TXBD_NUM - (tx_next - tx_last) - 1;
460 }
461 
462 static netdev_tx_t
463 greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
464 {
465 	struct greth_private *greth = netdev_priv(dev);
466 	struct greth_bd *bdp;
467 	u32 status, dma_addr;
468 	int curr_tx, nr_frags, i, err = NETDEV_TX_OK;
469 	unsigned long flags;
470 	u16 tx_last;
471 
472 	nr_frags = skb_shinfo(skb)->nr_frags;
473 	tx_last = greth->tx_last;
474 	rmb(); /* tx_last is updated by the poll task */
475 
476 	if (greth_num_free_bds(tx_last, greth->tx_next) < nr_frags + 1) {
477 		netif_stop_queue(dev);
478 		err = NETDEV_TX_BUSY;
479 		goto out;
480 	}
481 
482 	if (netif_msg_pktdata(greth))
483 		greth_print_tx_packet(skb);
484 
485 	if (unlikely(skb->len > MAX_FRAME_SIZE)) {
486 		dev->stats.tx_errors++;
487 		goto out;
488 	}
489 
490 	/* Save skb pointer. */
491 	greth->tx_skbuff[greth->tx_next] = skb;
492 
493 	/* Linear buf */
494 	if (nr_frags != 0)
495 		status = GRETH_TXBD_MORE;
496 	else
497 		status = GRETH_BD_IE;
498 
499 	if (skb->ip_summed == CHECKSUM_PARTIAL)
500 		status |= GRETH_TXBD_CSALL;
501 	status |= skb_headlen(skb) & GRETH_BD_LEN;
502 	if (greth->tx_next == GRETH_TXBD_NUM_MASK)
503 		status |= GRETH_BD_WR;
504 
505 
506 	bdp = greth->tx_bd_base + greth->tx_next;
507 	greth_write_bd(&bdp->stat, status);
508 	dma_addr = dma_map_single(greth->dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
509 
510 	if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
511 		goto map_error;
512 
513 	greth_write_bd(&bdp->addr, dma_addr);
514 
515 	curr_tx = NEXT_TX(greth->tx_next);
516 
517 	/* Frags */
518 	for (i = 0; i < nr_frags; i++) {
519 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
520 		greth->tx_skbuff[curr_tx] = NULL;
521 		bdp = greth->tx_bd_base + curr_tx;
522 
523 		status = GRETH_BD_EN;
524 		if (skb->ip_summed == CHECKSUM_PARTIAL)
525 			status |= GRETH_TXBD_CSALL;
526 		status |= skb_frag_size(frag) & GRETH_BD_LEN;
527 
528 		/* Wrap around descriptor ring */
529 		if (curr_tx == GRETH_TXBD_NUM_MASK)
530 			status |= GRETH_BD_WR;
531 
532 		/* More fragments left */
533 		if (i < nr_frags - 1)
534 			status |= GRETH_TXBD_MORE;
535 		else
536 			status |= GRETH_BD_IE; /* enable IRQ on last fragment */
537 
538 		greth_write_bd(&bdp->stat, status);
539 
540 		dma_addr = skb_frag_dma_map(greth->dev, frag, 0, skb_frag_size(frag),
541 					    DMA_TO_DEVICE);
542 
543 		if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
544 			goto frag_map_error;
545 
546 		greth_write_bd(&bdp->addr, dma_addr);
547 
548 		curr_tx = NEXT_TX(curr_tx);
549 	}
550 
551 	wmb();
552 
553 	/* Enable the descriptor chain by enabling the first descriptor */
554 	bdp = greth->tx_bd_base + greth->tx_next;
555 	greth_write_bd(&bdp->stat,
556 		       greth_read_bd(&bdp->stat) | GRETH_BD_EN);
557 
558 	spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
559 	greth->tx_next = curr_tx;
560 	greth_enable_tx_and_irq(greth);
561 	spin_unlock_irqrestore(&greth->devlock, flags);
562 
563 	return NETDEV_TX_OK;
564 
565 frag_map_error:
566 	/* Unmap SKB mappings that succeeded and disable descriptor */
567 	for (i = 0; greth->tx_next + i != curr_tx; i++) {
568 		bdp = greth->tx_bd_base + greth->tx_next + i;
569 		dma_unmap_single(greth->dev,
570 				 greth_read_bd(&bdp->addr),
571 				 greth_read_bd(&bdp->stat) & GRETH_BD_LEN,
572 				 DMA_TO_DEVICE);
573 		greth_write_bd(&bdp->stat, 0);
574 	}
575 map_error:
576 	if (net_ratelimit())
577 		dev_warn(greth->dev, "Could not create TX DMA mapping\n");
578 	dev_kfree_skb(skb);
579 out:
580 	return err;
581 }
582 
583 static irqreturn_t greth_interrupt(int irq, void *dev_id)
584 {
585 	struct net_device *dev = dev_id;
586 	struct greth_private *greth;
587 	u32 status, ctrl;
588 	irqreturn_t retval = IRQ_NONE;
589 
590 	greth = netdev_priv(dev);
591 
592 	spin_lock(&greth->devlock);
593 
594 	/* Get the interrupt events that caused us to be here. */
595 	status = GRETH_REGLOAD(greth->regs->status);
596 
597 	/* Must see if interrupts are enabled also, INT_TX|INT_RX flags may be
598 	 * set regardless of whether IRQ is enabled or not. Especially
599 	 * important when shared IRQ.
600 	 */
601 	ctrl = GRETH_REGLOAD(greth->regs->control);
602 
603 	/* Handle rx and tx interrupts through poll */
604 	if (((status & (GRETH_INT_RE | GRETH_INT_RX)) && (ctrl & GRETH_RXI)) ||
605 	    ((status & (GRETH_INT_TE | GRETH_INT_TX)) && (ctrl & GRETH_TXI))) {
606 		retval = IRQ_HANDLED;
607 
608 		/* Disable interrupts and schedule poll() */
609 		greth_disable_irqs(greth);
610 		napi_schedule(&greth->napi);
611 	}
612 
613 	spin_unlock(&greth->devlock);
614 
615 	return retval;
616 }
617 
618 static void greth_clean_tx(struct net_device *dev)
619 {
620 	struct greth_private *greth;
621 	struct greth_bd *bdp;
622 	u32 stat;
623 
624 	greth = netdev_priv(dev);
625 
626 	while (1) {
627 		bdp = greth->tx_bd_base + greth->tx_last;
628 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
629 		mb();
630 		stat = greth_read_bd(&bdp->stat);
631 
632 		if (unlikely(stat & GRETH_BD_EN))
633 			break;
634 
635 		if (greth->tx_free == GRETH_TXBD_NUM)
636 			break;
637 
638 		/* Check status for errors */
639 		if (unlikely(stat & GRETH_TXBD_STATUS)) {
640 			dev->stats.tx_errors++;
641 			if (stat & GRETH_TXBD_ERR_AL)
642 				dev->stats.tx_aborted_errors++;
643 			if (stat & GRETH_TXBD_ERR_UE)
644 				dev->stats.tx_fifo_errors++;
645 		}
646 		dev->stats.tx_packets++;
647 		dev->stats.tx_bytes += greth->tx_bufs_length[greth->tx_last];
648 		greth->tx_last = NEXT_TX(greth->tx_last);
649 		greth->tx_free++;
650 	}
651 
652 	if (greth->tx_free > 0) {
653 		netif_wake_queue(dev);
654 	}
655 }
656 
657 static inline void greth_update_tx_stats(struct net_device *dev, u32 stat)
658 {
659 	/* Check status for errors */
660 	if (unlikely(stat & GRETH_TXBD_STATUS)) {
661 		dev->stats.tx_errors++;
662 		if (stat & GRETH_TXBD_ERR_AL)
663 			dev->stats.tx_aborted_errors++;
664 		if (stat & GRETH_TXBD_ERR_UE)
665 			dev->stats.tx_fifo_errors++;
666 		if (stat & GRETH_TXBD_ERR_LC)
667 			dev->stats.tx_aborted_errors++;
668 	}
669 	dev->stats.tx_packets++;
670 }
671 
672 static void greth_clean_tx_gbit(struct net_device *dev)
673 {
674 	struct greth_private *greth;
675 	struct greth_bd *bdp, *bdp_last_frag;
676 	struct sk_buff *skb = NULL;
677 	u32 stat;
678 	int nr_frags, i;
679 	u16 tx_last;
680 
681 	greth = netdev_priv(dev);
682 	tx_last = greth->tx_last;
683 
684 	while (tx_last != greth->tx_next) {
685 
686 		skb = greth->tx_skbuff[tx_last];
687 
688 		nr_frags = skb_shinfo(skb)->nr_frags;
689 
690 		/* We only clean fully completed SKBs */
691 		bdp_last_frag = greth->tx_bd_base + SKIP_TX(tx_last, nr_frags);
692 
693 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
694 		mb();
695 		stat = greth_read_bd(&bdp_last_frag->stat);
696 
697 		if (stat & GRETH_BD_EN)
698 			break;
699 
700 		greth->tx_skbuff[tx_last] = NULL;
701 
702 		greth_update_tx_stats(dev, stat);
703 		dev->stats.tx_bytes += skb->len;
704 
705 		bdp = greth->tx_bd_base + tx_last;
706 
707 		tx_last = NEXT_TX(tx_last);
708 
709 		dma_unmap_single(greth->dev,
710 				 greth_read_bd(&bdp->addr),
711 				 skb_headlen(skb),
712 				 DMA_TO_DEVICE);
713 
714 		for (i = 0; i < nr_frags; i++) {
715 			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
716 			bdp = greth->tx_bd_base + tx_last;
717 
718 			dma_unmap_page(greth->dev,
719 				       greth_read_bd(&bdp->addr),
720 				       skb_frag_size(frag),
721 				       DMA_TO_DEVICE);
722 
723 			tx_last = NEXT_TX(tx_last);
724 		}
725 		dev_kfree_skb(skb);
726 	}
727 	if (skb) { /* skb is set only if the above while loop was entered */
728 		wmb();
729 		greth->tx_last = tx_last;
730 
731 		if (netif_queue_stopped(dev) &&
732 		    (greth_num_free_bds(tx_last, greth->tx_next) >
733 		    (MAX_SKB_FRAGS+1)))
734 			netif_wake_queue(dev);
735 	}
736 }
737 
738 static int greth_rx(struct net_device *dev, int limit)
739 {
740 	struct greth_private *greth;
741 	struct greth_bd *bdp;
742 	struct sk_buff *skb;
743 	int pkt_len;
744 	int bad, count;
745 	u32 status, dma_addr;
746 	unsigned long flags;
747 
748 	greth = netdev_priv(dev);
749 
750 	for (count = 0; count < limit; ++count) {
751 
752 		bdp = greth->rx_bd_base + greth->rx_cur;
753 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
754 		mb();
755 		status = greth_read_bd(&bdp->stat);
756 
757 		if (unlikely(status & GRETH_BD_EN)) {
758 			break;
759 		}
760 
761 		dma_addr = greth_read_bd(&bdp->addr);
762 		bad = 0;
763 
764 		/* Check status for errors. */
765 		if (unlikely(status & GRETH_RXBD_STATUS)) {
766 			if (status & GRETH_RXBD_ERR_FT) {
767 				dev->stats.rx_length_errors++;
768 				bad = 1;
769 			}
770 			if (status & (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE)) {
771 				dev->stats.rx_frame_errors++;
772 				bad = 1;
773 			}
774 			if (status & GRETH_RXBD_ERR_CRC) {
775 				dev->stats.rx_crc_errors++;
776 				bad = 1;
777 			}
778 		}
779 		if (unlikely(bad)) {
780 			dev->stats.rx_errors++;
781 
782 		} else {
783 
784 			pkt_len = status & GRETH_BD_LEN;
785 
786 			skb = netdev_alloc_skb(dev, pkt_len + NET_IP_ALIGN);
787 
788 			if (unlikely(skb == NULL)) {
789 
790 				if (net_ratelimit())
791 					dev_warn(&dev->dev, "low on memory - " "packet dropped\n");
792 
793 				dev->stats.rx_dropped++;
794 
795 			} else {
796 				skb_reserve(skb, NET_IP_ALIGN);
797 
798 				dma_sync_single_for_cpu(greth->dev,
799 							dma_addr,
800 							pkt_len,
801 							DMA_FROM_DEVICE);
802 
803 				if (netif_msg_pktdata(greth))
804 					greth_print_rx_packet(phys_to_virt(dma_addr), pkt_len);
805 
806 				skb_put_data(skb, phys_to_virt(dma_addr),
807 					     pkt_len);
808 
809 				skb->protocol = eth_type_trans(skb, dev);
810 				dev->stats.rx_bytes += pkt_len;
811 				dev->stats.rx_packets++;
812 				netif_receive_skb(skb);
813 			}
814 		}
815 
816 		status = GRETH_BD_EN | GRETH_BD_IE;
817 		if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
818 			status |= GRETH_BD_WR;
819 		}
820 
821 		wmb();
822 		greth_write_bd(&bdp->stat, status);
823 
824 		dma_sync_single_for_device(greth->dev, dma_addr, MAX_FRAME_SIZE, DMA_FROM_DEVICE);
825 
826 		spin_lock_irqsave(&greth->devlock, flags); /* save from XMIT */
827 		greth_enable_rx(greth);
828 		spin_unlock_irqrestore(&greth->devlock, flags);
829 
830 		greth->rx_cur = NEXT_RX(greth->rx_cur);
831 	}
832 
833 	return count;
834 }
835 
836 static inline int hw_checksummed(u32 status)
837 {
838 
839 	if (status & GRETH_RXBD_IP_FRAG)
840 		return 0;
841 
842 	if (status & GRETH_RXBD_IP && status & GRETH_RXBD_IP_CSERR)
843 		return 0;
844 
845 	if (status & GRETH_RXBD_UDP && status & GRETH_RXBD_UDP_CSERR)
846 		return 0;
847 
848 	if (status & GRETH_RXBD_TCP && status & GRETH_RXBD_TCP_CSERR)
849 		return 0;
850 
851 	return 1;
852 }
853 
854 static int greth_rx_gbit(struct net_device *dev, int limit)
855 {
856 	struct greth_private *greth;
857 	struct greth_bd *bdp;
858 	struct sk_buff *skb, *newskb;
859 	int pkt_len;
860 	int bad, count = 0;
861 	u32 status, dma_addr;
862 	unsigned long flags;
863 
864 	greth = netdev_priv(dev);
865 
866 	for (count = 0; count < limit; ++count) {
867 
868 		bdp = greth->rx_bd_base + greth->rx_cur;
869 		skb = greth->rx_skbuff[greth->rx_cur];
870 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
871 		mb();
872 		status = greth_read_bd(&bdp->stat);
873 		bad = 0;
874 
875 		if (status & GRETH_BD_EN)
876 			break;
877 
878 		/* Check status for errors. */
879 		if (unlikely(status & GRETH_RXBD_STATUS)) {
880 
881 			if (status & GRETH_RXBD_ERR_FT) {
882 				dev->stats.rx_length_errors++;
883 				bad = 1;
884 			} else if (status &
885 				   (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE | GRETH_RXBD_ERR_LE)) {
886 				dev->stats.rx_frame_errors++;
887 				bad = 1;
888 			} else if (status & GRETH_RXBD_ERR_CRC) {
889 				dev->stats.rx_crc_errors++;
890 				bad = 1;
891 			}
892 		}
893 
894 		/* Allocate new skb to replace current, not needed if the
895 		 * current skb can be reused */
896 		if (!bad && (newskb=netdev_alloc_skb(dev, MAX_FRAME_SIZE + NET_IP_ALIGN))) {
897 			skb_reserve(newskb, NET_IP_ALIGN);
898 
899 			dma_addr = dma_map_single(greth->dev,
900 						      newskb->data,
901 						      MAX_FRAME_SIZE + NET_IP_ALIGN,
902 						      DMA_FROM_DEVICE);
903 
904 			if (!dma_mapping_error(greth->dev, dma_addr)) {
905 				/* Process the incoming frame. */
906 				pkt_len = status & GRETH_BD_LEN;
907 
908 				dma_unmap_single(greth->dev,
909 						 greth_read_bd(&bdp->addr),
910 						 MAX_FRAME_SIZE + NET_IP_ALIGN,
911 						 DMA_FROM_DEVICE);
912 
913 				if (netif_msg_pktdata(greth))
914 					greth_print_rx_packet(phys_to_virt(greth_read_bd(&bdp->addr)), pkt_len);
915 
916 				skb_put(skb, pkt_len);
917 
918 				if (dev->features & NETIF_F_RXCSUM && hw_checksummed(status))
919 					skb->ip_summed = CHECKSUM_UNNECESSARY;
920 				else
921 					skb_checksum_none_assert(skb);
922 
923 				skb->protocol = eth_type_trans(skb, dev);
924 				dev->stats.rx_packets++;
925 				dev->stats.rx_bytes += pkt_len;
926 				netif_receive_skb(skb);
927 
928 				greth->rx_skbuff[greth->rx_cur] = newskb;
929 				greth_write_bd(&bdp->addr, dma_addr);
930 			} else {
931 				if (net_ratelimit())
932 					dev_warn(greth->dev, "Could not create DMA mapping, dropping packet\n");
933 				dev_kfree_skb(newskb);
934 				/* reusing current skb, so it is a drop */
935 				dev->stats.rx_dropped++;
936 			}
937 		} else if (bad) {
938 			/* Bad Frame transfer, the skb is reused */
939 			dev->stats.rx_dropped++;
940 		} else {
941 			/* Failed Allocating a new skb. This is rather stupid
942 			 * but the current "filled" skb is reused, as if
943 			 * transfer failure. One could argue that RX descriptor
944 			 * table handling should be divided into cleaning and
945 			 * filling as the TX part of the driver
946 			 */
947 			if (net_ratelimit())
948 				dev_warn(greth->dev, "Could not allocate SKB, dropping packet\n");
949 			/* reusing current skb, so it is a drop */
950 			dev->stats.rx_dropped++;
951 		}
952 
953 		status = GRETH_BD_EN | GRETH_BD_IE;
954 		if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
955 			status |= GRETH_BD_WR;
956 		}
957 
958 		wmb();
959 		greth_write_bd(&bdp->stat, status);
960 		spin_lock_irqsave(&greth->devlock, flags);
961 		greth_enable_rx(greth);
962 		spin_unlock_irqrestore(&greth->devlock, flags);
963 		greth->rx_cur = NEXT_RX(greth->rx_cur);
964 	}
965 
966 	return count;
967 
968 }
969 
970 static int greth_poll(struct napi_struct *napi, int budget)
971 {
972 	struct greth_private *greth;
973 	int work_done = 0;
974 	unsigned long flags;
975 	u32 mask, ctrl;
976 	greth = container_of(napi, struct greth_private, napi);
977 
978 restart_txrx_poll:
979 	if (greth->gbit_mac) {
980 		greth_clean_tx_gbit(greth->netdev);
981 		work_done += greth_rx_gbit(greth->netdev, budget - work_done);
982 	} else {
983 		if (netif_queue_stopped(greth->netdev))
984 			greth_clean_tx(greth->netdev);
985 		work_done += greth_rx(greth->netdev, budget - work_done);
986 	}
987 
988 	if (work_done < budget) {
989 
990 		spin_lock_irqsave(&greth->devlock, flags);
991 
992 		ctrl = GRETH_REGLOAD(greth->regs->control);
993 		if ((greth->gbit_mac && (greth->tx_last != greth->tx_next)) ||
994 		    (!greth->gbit_mac && netif_queue_stopped(greth->netdev))) {
995 			GRETH_REGSAVE(greth->regs->control,
996 					ctrl | GRETH_TXI | GRETH_RXI);
997 			mask = GRETH_INT_RX | GRETH_INT_RE |
998 			       GRETH_INT_TX | GRETH_INT_TE;
999 		} else {
1000 			GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_RXI);
1001 			mask = GRETH_INT_RX | GRETH_INT_RE;
1002 		}
1003 
1004 		if (GRETH_REGLOAD(greth->regs->status) & mask) {
1005 			GRETH_REGSAVE(greth->regs->control, ctrl);
1006 			spin_unlock_irqrestore(&greth->devlock, flags);
1007 			goto restart_txrx_poll;
1008 		} else {
1009 			napi_complete_done(napi, work_done);
1010 			spin_unlock_irqrestore(&greth->devlock, flags);
1011 		}
1012 	}
1013 
1014 	return work_done;
1015 }
1016 
1017 static int greth_set_mac_add(struct net_device *dev, void *p)
1018 {
1019 	struct sockaddr *addr = p;
1020 	struct greth_private *greth;
1021 	struct greth_regs *regs;
1022 
1023 	greth = netdev_priv(dev);
1024 	regs = greth->regs;
1025 
1026 	if (!is_valid_ether_addr(addr->sa_data))
1027 		return -EADDRNOTAVAIL;
1028 
1029 	eth_hw_addr_set(dev, addr->sa_data);
1030 	GRETH_REGSAVE(regs->esa_msb, dev->dev_addr[0] << 8 | dev->dev_addr[1]);
1031 	GRETH_REGSAVE(regs->esa_lsb, dev->dev_addr[2] << 24 | dev->dev_addr[3] << 16 |
1032 		      dev->dev_addr[4] << 8 | dev->dev_addr[5]);
1033 
1034 	return 0;
1035 }
1036 
1037 static u32 greth_hash_get_index(__u8 *addr)
1038 {
1039 	return (ether_crc(6, addr)) & 0x3F;
1040 }
1041 
1042 static void greth_set_hash_filter(struct net_device *dev)
1043 {
1044 	struct netdev_hw_addr *ha;
1045 	struct greth_private *greth = netdev_priv(dev);
1046 	struct greth_regs *regs = greth->regs;
1047 	u32 mc_filter[2];
1048 	unsigned int bitnr;
1049 
1050 	mc_filter[0] = mc_filter[1] = 0;
1051 
1052 	netdev_for_each_mc_addr(ha, dev) {
1053 		bitnr = greth_hash_get_index(ha->addr);
1054 		mc_filter[bitnr >> 5] |= 1 << (bitnr & 31);
1055 	}
1056 
1057 	GRETH_REGSAVE(regs->hash_msb, mc_filter[1]);
1058 	GRETH_REGSAVE(regs->hash_lsb, mc_filter[0]);
1059 }
1060 
1061 static void greth_set_multicast_list(struct net_device *dev)
1062 {
1063 	int cfg;
1064 	struct greth_private *greth = netdev_priv(dev);
1065 	struct greth_regs *regs = greth->regs;
1066 
1067 	cfg = GRETH_REGLOAD(regs->control);
1068 	if (dev->flags & IFF_PROMISC)
1069 		cfg |= GRETH_CTRL_PR;
1070 	else
1071 		cfg &= ~GRETH_CTRL_PR;
1072 
1073 	if (greth->multicast) {
1074 		if (dev->flags & IFF_ALLMULTI) {
1075 			GRETH_REGSAVE(regs->hash_msb, -1);
1076 			GRETH_REGSAVE(regs->hash_lsb, -1);
1077 			cfg |= GRETH_CTRL_MCEN;
1078 			GRETH_REGSAVE(regs->control, cfg);
1079 			return;
1080 		}
1081 
1082 		if (netdev_mc_empty(dev)) {
1083 			cfg &= ~GRETH_CTRL_MCEN;
1084 			GRETH_REGSAVE(regs->control, cfg);
1085 			return;
1086 		}
1087 
1088 		/* Setup multicast filter */
1089 		greth_set_hash_filter(dev);
1090 		cfg |= GRETH_CTRL_MCEN;
1091 	}
1092 	GRETH_REGSAVE(regs->control, cfg);
1093 }
1094 
1095 static u32 greth_get_msglevel(struct net_device *dev)
1096 {
1097 	struct greth_private *greth = netdev_priv(dev);
1098 	return greth->msg_enable;
1099 }
1100 
1101 static void greth_set_msglevel(struct net_device *dev, u32 value)
1102 {
1103 	struct greth_private *greth = netdev_priv(dev);
1104 	greth->msg_enable = value;
1105 }
1106 
1107 static int greth_get_regs_len(struct net_device *dev)
1108 {
1109 	return sizeof(struct greth_regs);
1110 }
1111 
1112 static void greth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1113 {
1114 	struct greth_private *greth = netdev_priv(dev);
1115 
1116 	strscpy(info->driver, dev_driver_string(greth->dev),
1117 		sizeof(info->driver));
1118 	strscpy(info->bus_info, greth->dev->bus->name, sizeof(info->bus_info));
1119 }
1120 
1121 static void greth_get_regs(struct net_device *dev, struct ethtool_regs *regs, void *p)
1122 {
1123 	int i;
1124 	struct greth_private *greth = netdev_priv(dev);
1125 	u32 __iomem *greth_regs = (u32 __iomem *) greth->regs;
1126 	u32 *buff = p;
1127 
1128 	for (i = 0; i < sizeof(struct greth_regs) / sizeof(u32); i++)
1129 		buff[i] = greth_read_bd(&greth_regs[i]);
1130 }
1131 
1132 static const struct ethtool_ops greth_ethtool_ops = {
1133 	.get_msglevel		= greth_get_msglevel,
1134 	.set_msglevel		= greth_set_msglevel,
1135 	.get_drvinfo		= greth_get_drvinfo,
1136 	.get_regs_len           = greth_get_regs_len,
1137 	.get_regs               = greth_get_regs,
1138 	.get_link		= ethtool_op_get_link,
1139 	.get_link_ksettings	= phy_ethtool_get_link_ksettings,
1140 	.set_link_ksettings	= phy_ethtool_set_link_ksettings,
1141 };
1142 
1143 static struct net_device_ops greth_netdev_ops = {
1144 	.ndo_open		= greth_open,
1145 	.ndo_stop		= greth_close,
1146 	.ndo_start_xmit		= greth_start_xmit,
1147 	.ndo_set_mac_address	= greth_set_mac_add,
1148 	.ndo_validate_addr	= eth_validate_addr,
1149 };
1150 
1151 static inline int wait_for_mdio(struct greth_private *greth)
1152 {
1153 	unsigned long timeout = jiffies + 4*HZ/100;
1154 	while (GRETH_REGLOAD(greth->regs->mdio) & GRETH_MII_BUSY) {
1155 		if (time_after(jiffies, timeout))
1156 			return 0;
1157 	}
1158 	return 1;
1159 }
1160 
1161 static int greth_mdio_read(struct mii_bus *bus, int phy, int reg)
1162 {
1163 	struct greth_private *greth = bus->priv;
1164 	int data;
1165 
1166 	if (!wait_for_mdio(greth))
1167 		return -EBUSY;
1168 
1169 	GRETH_REGSAVE(greth->regs->mdio, ((phy & 0x1F) << 11) | ((reg & 0x1F) << 6) | 2);
1170 
1171 	if (!wait_for_mdio(greth))
1172 		return -EBUSY;
1173 
1174 	if (!(GRETH_REGLOAD(greth->regs->mdio) & GRETH_MII_NVALID)) {
1175 		data = (GRETH_REGLOAD(greth->regs->mdio) >> 16) & 0xFFFF;
1176 		return data;
1177 
1178 	} else {
1179 		return -1;
1180 	}
1181 }
1182 
1183 static int greth_mdio_write(struct mii_bus *bus, int phy, int reg, u16 val)
1184 {
1185 	struct greth_private *greth = bus->priv;
1186 
1187 	if (!wait_for_mdio(greth))
1188 		return -EBUSY;
1189 
1190 	GRETH_REGSAVE(greth->regs->mdio,
1191 		      ((val & 0xFFFF) << 16) | ((phy & 0x1F) << 11) | ((reg & 0x1F) << 6) | 1);
1192 
1193 	if (!wait_for_mdio(greth))
1194 		return -EBUSY;
1195 
1196 	return 0;
1197 }
1198 
1199 static void greth_link_change(struct net_device *dev)
1200 {
1201 	struct greth_private *greth = netdev_priv(dev);
1202 	struct phy_device *phydev = dev->phydev;
1203 	unsigned long flags;
1204 	int status_change = 0;
1205 	u32 ctrl;
1206 
1207 	spin_lock_irqsave(&greth->devlock, flags);
1208 
1209 	if (phydev->link) {
1210 
1211 		if ((greth->speed != phydev->speed) || (greth->duplex != phydev->duplex)) {
1212 			ctrl = GRETH_REGLOAD(greth->regs->control) &
1213 			       ~(GRETH_CTRL_FD | GRETH_CTRL_SP | GRETH_CTRL_GB);
1214 
1215 			if (phydev->duplex)
1216 				ctrl |= GRETH_CTRL_FD;
1217 
1218 			if (phydev->speed == SPEED_100)
1219 				ctrl |= GRETH_CTRL_SP;
1220 			else if (phydev->speed == SPEED_1000)
1221 				ctrl |= GRETH_CTRL_GB;
1222 
1223 			GRETH_REGSAVE(greth->regs->control, ctrl);
1224 			greth->speed = phydev->speed;
1225 			greth->duplex = phydev->duplex;
1226 			status_change = 1;
1227 		}
1228 	}
1229 
1230 	if (phydev->link != greth->link) {
1231 		if (!phydev->link) {
1232 			greth->speed = 0;
1233 			greth->duplex = -1;
1234 		}
1235 		greth->link = phydev->link;
1236 
1237 		status_change = 1;
1238 	}
1239 
1240 	spin_unlock_irqrestore(&greth->devlock, flags);
1241 
1242 	if (status_change) {
1243 		if (phydev->link)
1244 			pr_debug("%s: link up (%d/%s)\n",
1245 				dev->name, phydev->speed,
1246 				DUPLEX_FULL == phydev->duplex ? "Full" : "Half");
1247 		else
1248 			pr_debug("%s: link down\n", dev->name);
1249 	}
1250 }
1251 
1252 static int greth_mdio_probe(struct net_device *dev)
1253 {
1254 	struct greth_private *greth = netdev_priv(dev);
1255 	struct phy_device *phy = NULL;
1256 	int ret;
1257 
1258 	/* Find the first PHY */
1259 	phy = phy_find_first(greth->mdio);
1260 
1261 	if (!phy) {
1262 		if (netif_msg_probe(greth))
1263 			dev_err(&dev->dev, "no PHY found\n");
1264 		return -ENXIO;
1265 	}
1266 
1267 	ret = phy_connect_direct(dev, phy, &greth_link_change,
1268 				 greth->gbit_mac ? PHY_INTERFACE_MODE_GMII : PHY_INTERFACE_MODE_MII);
1269 	if (ret) {
1270 		if (netif_msg_ifup(greth))
1271 			dev_err(&dev->dev, "could not attach to PHY\n");
1272 		return ret;
1273 	}
1274 
1275 	if (greth->gbit_mac)
1276 		phy_set_max_speed(phy, SPEED_1000);
1277 	else
1278 		phy_set_max_speed(phy, SPEED_100);
1279 
1280 	linkmode_copy(phy->advertising, phy->supported);
1281 
1282 	greth->link = 0;
1283 	greth->speed = 0;
1284 	greth->duplex = -1;
1285 
1286 	return 0;
1287 }
1288 
1289 static int greth_mdio_init(struct greth_private *greth)
1290 {
1291 	int ret;
1292 	unsigned long timeout;
1293 	struct net_device *ndev = greth->netdev;
1294 
1295 	greth->mdio = mdiobus_alloc();
1296 	if (!greth->mdio) {
1297 		return -ENOMEM;
1298 	}
1299 
1300 	greth->mdio->name = "greth-mdio";
1301 	snprintf(greth->mdio->id, MII_BUS_ID_SIZE, "%s-%d", greth->mdio->name, greth->irq);
1302 	greth->mdio->read = greth_mdio_read;
1303 	greth->mdio->write = greth_mdio_write;
1304 	greth->mdio->priv = greth;
1305 
1306 	ret = mdiobus_register(greth->mdio);
1307 	if (ret) {
1308 		goto error;
1309 	}
1310 
1311 	ret = greth_mdio_probe(greth->netdev);
1312 	if (ret) {
1313 		if (netif_msg_probe(greth))
1314 			dev_err(&greth->netdev->dev, "failed to probe MDIO bus\n");
1315 		goto unreg_mdio;
1316 	}
1317 
1318 	phy_start(ndev->phydev);
1319 
1320 	/* If Ethernet debug link is used make autoneg happen right away */
1321 	if (greth->edcl && greth_edcl == 1) {
1322 		phy_start_aneg(ndev->phydev);
1323 		timeout = jiffies + 6*HZ;
1324 		while (!phy_aneg_done(ndev->phydev) &&
1325 		       time_before(jiffies, timeout)) {
1326 		}
1327 		phy_read_status(ndev->phydev);
1328 		greth_link_change(greth->netdev);
1329 	}
1330 
1331 	return 0;
1332 
1333 unreg_mdio:
1334 	mdiobus_unregister(greth->mdio);
1335 error:
1336 	mdiobus_free(greth->mdio);
1337 	return ret;
1338 }
1339 
1340 /* Initialize the GRETH MAC */
1341 static int greth_of_probe(struct platform_device *ofdev)
1342 {
1343 	struct net_device *dev;
1344 	struct greth_private *greth;
1345 	struct greth_regs *regs;
1346 
1347 	int i;
1348 	int err;
1349 	int tmp;
1350 	u8 addr[ETH_ALEN];
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 		err = of_get_mac_address(ofdev->dev.of_node, addr);
1455 		if (!err) {
1456 			for (i = 0; i < 6; i++)
1457 				macaddr[i] = (unsigned int) addr[i];
1458 		} else {
1459 #ifdef CONFIG_SPARC
1460 			for (i = 0; i < 6; i++)
1461 				macaddr[i] = (unsigned int) idprom->id_ethaddr[i];
1462 #endif
1463 		}
1464 	}
1465 
1466 	for (i = 0; i < 6; i++)
1467 		addr[i] = macaddr[i];
1468 	eth_hw_addr_set(dev, addr);
1469 
1470 	macaddr[5]++;
1471 
1472 	if (!is_valid_ether_addr(&dev->dev_addr[0])) {
1473 		if (netif_msg_probe(greth))
1474 			dev_err(greth->dev, "no valid ethernet address, aborting.\n");
1475 		err = -EINVAL;
1476 		goto error5;
1477 	}
1478 
1479 	GRETH_REGSAVE(regs->esa_msb, dev->dev_addr[0] << 8 | dev->dev_addr[1]);
1480 	GRETH_REGSAVE(regs->esa_lsb, dev->dev_addr[2] << 24 | dev->dev_addr[3] << 16 |
1481 		      dev->dev_addr[4] << 8 | dev->dev_addr[5]);
1482 
1483 	/* Clear all pending interrupts except PHY irq */
1484 	GRETH_REGSAVE(regs->status, 0xFF);
1485 
1486 	if (greth->gbit_mac) {
1487 		dev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM |
1488 			NETIF_F_RXCSUM;
1489 		dev->features = dev->hw_features | NETIF_F_HIGHDMA;
1490 		greth_netdev_ops.ndo_start_xmit = greth_start_xmit_gbit;
1491 	}
1492 
1493 	if (greth->multicast) {
1494 		greth_netdev_ops.ndo_set_rx_mode = greth_set_multicast_list;
1495 		dev->flags |= IFF_MULTICAST;
1496 	} else {
1497 		dev->flags &= ~IFF_MULTICAST;
1498 	}
1499 
1500 	dev->netdev_ops = &greth_netdev_ops;
1501 	dev->ethtool_ops = &greth_ethtool_ops;
1502 
1503 	err = register_netdev(dev);
1504 	if (err) {
1505 		if (netif_msg_probe(greth))
1506 			dev_err(greth->dev, "netdevice registration failed.\n");
1507 		goto error5;
1508 	}
1509 
1510 	/* setup NAPI */
1511 	netif_napi_add(dev, &greth->napi, greth_poll);
1512 
1513 	return 0;
1514 
1515 error5:
1516 	dma_free_coherent(greth->dev, 1024, greth->rx_bd_base, greth->rx_bd_base_phys);
1517 error4:
1518 	dma_free_coherent(greth->dev, 1024, greth->tx_bd_base, greth->tx_bd_base_phys);
1519 error3:
1520 	mdiobus_unregister(greth->mdio);
1521 error2:
1522 	of_iounmap(&ofdev->resource[0], greth->regs, resource_size(&ofdev->resource[0]));
1523 error1:
1524 	free_netdev(dev);
1525 	return err;
1526 }
1527 
1528 static int greth_of_remove(struct platform_device *of_dev)
1529 {
1530 	struct net_device *ndev = platform_get_drvdata(of_dev);
1531 	struct greth_private *greth = netdev_priv(ndev);
1532 
1533 	/* Free descriptor areas */
1534 	dma_free_coherent(&of_dev->dev, 1024, greth->rx_bd_base, greth->rx_bd_base_phys);
1535 
1536 	dma_free_coherent(&of_dev->dev, 1024, greth->tx_bd_base, greth->tx_bd_base_phys);
1537 
1538 	if (ndev->phydev)
1539 		phy_stop(ndev->phydev);
1540 	mdiobus_unregister(greth->mdio);
1541 
1542 	unregister_netdev(ndev);
1543 
1544 	of_iounmap(&of_dev->resource[0], greth->regs, resource_size(&of_dev->resource[0]));
1545 
1546 	free_netdev(ndev);
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