1 /*
2  * Aeroflex Gaisler GRETH 10/100/1G Ethernet MAC.
3  *
4  * 2005-2010 (c) Aeroflex Gaisler AB
5  *
6  * This driver supports GRETH 10/100 and GRETH 10/100/1G Ethernet MACs
7  * available in the GRLIB VHDL IP core library.
8  *
9  * Full documentation of both cores can be found here:
10  * http://www.gaisler.com/products/grlib/grip.pdf
11  *
12  * The Gigabit version supports scatter/gather DMA, any alignment of
13  * buffers and checksum offloading.
14  *
15  * This program is free software; you can redistribute it and/or modify it
16  * under the terms of the GNU General Public License as published by the
17  * Free Software Foundation; either version 2 of the License, or (at your
18  * option) any later version.
19  *
20  * Contributors: Kristoffer Glembo
21  *               Daniel Hellstrom
22  *               Marko Isomaki
23  */
24 
25 #include <linux/dma-mapping.h>
26 #include <linux/module.h>
27 #include <linux/uaccess.h>
28 #include <linux/interrupt.h>
29 #include <linux/netdevice.h>
30 #include <linux/etherdevice.h>
31 #include <linux/ethtool.h>
32 #include <linux/skbuff.h>
33 #include <linux/io.h>
34 #include <linux/crc32.h>
35 #include <linux/mii.h>
36 #include <linux/of_device.h>
37 #include <linux/of_net.h>
38 #include <linux/of_platform.h>
39 #include <linux/slab.h>
40 #include <asm/cacheflush.h>
41 #include <asm/byteorder.h>
42 
43 #ifdef CONFIG_SPARC
44 #include <asm/idprom.h>
45 #endif
46 
47 #include "greth.h"
48 
49 #define GRETH_DEF_MSG_ENABLE	  \
50 	(NETIF_MSG_DRV		| \
51 	 NETIF_MSG_PROBE	| \
52 	 NETIF_MSG_LINK		| \
53 	 NETIF_MSG_IFDOWN	| \
54 	 NETIF_MSG_IFUP		| \
55 	 NETIF_MSG_RX_ERR	| \
56 	 NETIF_MSG_TX_ERR)
57 
58 static int greth_debug = -1;	/* -1 == use GRETH_DEF_MSG_ENABLE as value */
59 module_param(greth_debug, int, 0);
60 MODULE_PARM_DESC(greth_debug, "GRETH bitmapped debugging message enable value");
61 
62 /* Accept MAC address of the form macaddr=0x08,0x00,0x20,0x30,0x40,0x50 */
63 static int macaddr[6];
64 module_param_array(macaddr, int, NULL, 0);
65 MODULE_PARM_DESC(macaddr, "GRETH Ethernet MAC address");
66 
67 static int greth_edcl = 1;
68 module_param(greth_edcl, int, 0);
69 MODULE_PARM_DESC(greth_edcl, "GRETH EDCL usage indicator. Set to 1 if EDCL is used.");
70 
71 static int greth_open(struct net_device *dev);
72 static netdev_tx_t greth_start_xmit(struct sk_buff *skb,
73 	   struct net_device *dev);
74 static netdev_tx_t greth_start_xmit_gbit(struct sk_buff *skb,
75 	   struct net_device *dev);
76 static int greth_rx(struct net_device *dev, int limit);
77 static int greth_rx_gbit(struct net_device *dev, int limit);
78 static void greth_clean_tx(struct net_device *dev);
79 static void greth_clean_tx_gbit(struct net_device *dev);
80 static irqreturn_t greth_interrupt(int irq, void *dev_id);
81 static int greth_close(struct net_device *dev);
82 static int greth_set_mac_add(struct net_device *dev, void *p);
83 static void greth_set_multicast_list(struct net_device *dev);
84 
85 #define GRETH_REGLOAD(a)	    (be32_to_cpu(__raw_readl(&(a))))
86 #define GRETH_REGSAVE(a, v)         (__raw_writel(cpu_to_be32(v), &(a)))
87 #define GRETH_REGORIN(a, v)         (GRETH_REGSAVE(a, (GRETH_REGLOAD(a) | (v))))
88 #define GRETH_REGANDIN(a, v)        (GRETH_REGSAVE(a, (GRETH_REGLOAD(a) & (v))))
89 
90 #define NEXT_TX(N)      (((N) + 1) & GRETH_TXBD_NUM_MASK)
91 #define SKIP_TX(N, C)   (((N) + C) & GRETH_TXBD_NUM_MASK)
92 #define NEXT_RX(N)      (((N) + 1) & GRETH_RXBD_NUM_MASK)
93 
94 static void greth_print_rx_packet(void *addr, int len)
95 {
96 	print_hex_dump(KERN_DEBUG, "RX: ", DUMP_PREFIX_OFFSET, 16, 1,
97 			addr, len, true);
98 }
99 
100 static void greth_print_tx_packet(struct sk_buff *skb)
101 {
102 	int i;
103 	int length;
104 
105 	if (skb_shinfo(skb)->nr_frags == 0)
106 		length = skb->len;
107 	else
108 		length = skb_headlen(skb);
109 
110 	print_hex_dump(KERN_DEBUG, "TX: ", DUMP_PREFIX_OFFSET, 16, 1,
111 			skb->data, length, true);
112 
113 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
114 
115 		print_hex_dump(KERN_DEBUG, "TX: ", DUMP_PREFIX_OFFSET, 16, 1,
116 			       skb_frag_address(&skb_shinfo(skb)->frags[i]),
117 			       skb_shinfo(skb)->frags[i].size, true);
118 	}
119 }
120 
121 static inline void greth_enable_tx(struct greth_private *greth)
122 {
123 	wmb();
124 	GRETH_REGORIN(greth->regs->control, GRETH_TXEN);
125 }
126 
127 static inline void greth_enable_tx_and_irq(struct greth_private *greth)
128 {
129 	wmb(); /* BDs must been written to memory before enabling TX */
130 	GRETH_REGORIN(greth->regs->control, GRETH_TXEN | GRETH_TXI);
131 }
132 
133 static inline void greth_disable_tx(struct greth_private *greth)
134 {
135 	GRETH_REGANDIN(greth->regs->control, ~GRETH_TXEN);
136 }
137 
138 static inline void greth_enable_rx(struct greth_private *greth)
139 {
140 	wmb();
141 	GRETH_REGORIN(greth->regs->control, GRETH_RXEN);
142 }
143 
144 static inline void greth_disable_rx(struct greth_private *greth)
145 {
146 	GRETH_REGANDIN(greth->regs->control, ~GRETH_RXEN);
147 }
148 
149 static inline void greth_enable_irqs(struct greth_private *greth)
150 {
151 	GRETH_REGORIN(greth->regs->control, GRETH_RXI | GRETH_TXI);
152 }
153 
154 static inline void greth_disable_irqs(struct greth_private *greth)
155 {
156 	GRETH_REGANDIN(greth->regs->control, ~(GRETH_RXI|GRETH_TXI));
157 }
158 
159 static inline void greth_write_bd(u32 *bd, u32 val)
160 {
161 	__raw_writel(cpu_to_be32(val), bd);
162 }
163 
164 static inline u32 greth_read_bd(u32 *bd)
165 {
166 	return be32_to_cpu(__raw_readl(bd));
167 }
168 
169 static void greth_clean_rings(struct greth_private *greth)
170 {
171 	int i;
172 	struct greth_bd *rx_bdp = greth->rx_bd_base;
173 	struct greth_bd *tx_bdp = greth->tx_bd_base;
174 
175 	if (greth->gbit_mac) {
176 
177 		/* Free and unmap RX buffers */
178 		for (i = 0; i < GRETH_RXBD_NUM; i++, rx_bdp++) {
179 			if (greth->rx_skbuff[i] != NULL) {
180 				dev_kfree_skb(greth->rx_skbuff[i]);
181 				dma_unmap_single(greth->dev,
182 						 greth_read_bd(&rx_bdp->addr),
183 						 MAX_FRAME_SIZE+NET_IP_ALIGN,
184 						 DMA_FROM_DEVICE);
185 			}
186 		}
187 
188 		/* TX buffers */
189 		while (greth->tx_free < GRETH_TXBD_NUM) {
190 
191 			struct sk_buff *skb = greth->tx_skbuff[greth->tx_last];
192 			int nr_frags = skb_shinfo(skb)->nr_frags;
193 			tx_bdp = greth->tx_bd_base + greth->tx_last;
194 			greth->tx_last = NEXT_TX(greth->tx_last);
195 
196 			dma_unmap_single(greth->dev,
197 					 greth_read_bd(&tx_bdp->addr),
198 					 skb_headlen(skb),
199 					 DMA_TO_DEVICE);
200 
201 			for (i = 0; i < nr_frags; i++) {
202 				skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
203 				tx_bdp = greth->tx_bd_base + greth->tx_last;
204 
205 				dma_unmap_page(greth->dev,
206 					       greth_read_bd(&tx_bdp->addr),
207 					       skb_frag_size(frag),
208 					       DMA_TO_DEVICE);
209 
210 				greth->tx_last = NEXT_TX(greth->tx_last);
211 			}
212 			greth->tx_free += nr_frags+1;
213 			dev_kfree_skb(skb);
214 		}
215 
216 
217 	} else { /* 10/100 Mbps MAC */
218 
219 		for (i = 0; i < GRETH_RXBD_NUM; i++, rx_bdp++) {
220 			kfree(greth->rx_bufs[i]);
221 			dma_unmap_single(greth->dev,
222 					 greth_read_bd(&rx_bdp->addr),
223 					 MAX_FRAME_SIZE,
224 					 DMA_FROM_DEVICE);
225 		}
226 		for (i = 0; i < GRETH_TXBD_NUM; i++, tx_bdp++) {
227 			kfree(greth->tx_bufs[i]);
228 			dma_unmap_single(greth->dev,
229 					 greth_read_bd(&tx_bdp->addr),
230 					 MAX_FRAME_SIZE,
231 					 DMA_TO_DEVICE);
232 		}
233 	}
234 }
235 
236 static int greth_init_rings(struct greth_private *greth)
237 {
238 	struct sk_buff *skb;
239 	struct greth_bd *rx_bd, *tx_bd;
240 	u32 dma_addr;
241 	int i;
242 
243 	rx_bd = greth->rx_bd_base;
244 	tx_bd = greth->tx_bd_base;
245 
246 	/* Initialize descriptor rings and buffers */
247 	if (greth->gbit_mac) {
248 
249 		for (i = 0; i < GRETH_RXBD_NUM; i++) {
250 			skb = netdev_alloc_skb(greth->netdev, MAX_FRAME_SIZE+NET_IP_ALIGN);
251 			if (skb == NULL) {
252 				if (netif_msg_ifup(greth))
253 					dev_err(greth->dev, "Error allocating DMA ring.\n");
254 				goto cleanup;
255 			}
256 			skb_reserve(skb, NET_IP_ALIGN);
257 			dma_addr = dma_map_single(greth->dev,
258 						  skb->data,
259 						  MAX_FRAME_SIZE+NET_IP_ALIGN,
260 						  DMA_FROM_DEVICE);
261 
262 			if (dma_mapping_error(greth->dev, dma_addr)) {
263 				if (netif_msg_ifup(greth))
264 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
265 				goto cleanup;
266 			}
267 			greth->rx_skbuff[i] = skb;
268 			greth_write_bd(&rx_bd[i].addr, dma_addr);
269 			greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
270 		}
271 
272 	} else {
273 
274 		/* 10/100 MAC uses a fixed set of buffers and copy to/from SKBs */
275 		for (i = 0; i < GRETH_RXBD_NUM; i++) {
276 
277 			greth->rx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);
278 
279 			if (greth->rx_bufs[i] == NULL) {
280 				if (netif_msg_ifup(greth))
281 					dev_err(greth->dev, "Error allocating DMA ring.\n");
282 				goto cleanup;
283 			}
284 
285 			dma_addr = dma_map_single(greth->dev,
286 						  greth->rx_bufs[i],
287 						  MAX_FRAME_SIZE,
288 						  DMA_FROM_DEVICE);
289 
290 			if (dma_mapping_error(greth->dev, dma_addr)) {
291 				if (netif_msg_ifup(greth))
292 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
293 				goto cleanup;
294 			}
295 			greth_write_bd(&rx_bd[i].addr, dma_addr);
296 			greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
297 		}
298 		for (i = 0; i < GRETH_TXBD_NUM; i++) {
299 
300 			greth->tx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);
301 
302 			if (greth->tx_bufs[i] == NULL) {
303 				if (netif_msg_ifup(greth))
304 					dev_err(greth->dev, "Error allocating DMA ring.\n");
305 				goto cleanup;
306 			}
307 
308 			dma_addr = dma_map_single(greth->dev,
309 						  greth->tx_bufs[i],
310 						  MAX_FRAME_SIZE,
311 						  DMA_TO_DEVICE);
312 
313 			if (dma_mapping_error(greth->dev, dma_addr)) {
314 				if (netif_msg_ifup(greth))
315 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
316 				goto cleanup;
317 			}
318 			greth_write_bd(&tx_bd[i].addr, dma_addr);
319 			greth_write_bd(&tx_bd[i].stat, 0);
320 		}
321 	}
322 	greth_write_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat,
323 		       greth_read_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat) | GRETH_BD_WR);
324 
325 	/* Initialize pointers. */
326 	greth->rx_cur = 0;
327 	greth->tx_next = 0;
328 	greth->tx_last = 0;
329 	greth->tx_free = GRETH_TXBD_NUM;
330 
331 	/* Initialize descriptor base address */
332 	GRETH_REGSAVE(greth->regs->tx_desc_p, greth->tx_bd_base_phys);
333 	GRETH_REGSAVE(greth->regs->rx_desc_p, greth->rx_bd_base_phys);
334 
335 	return 0;
336 
337 cleanup:
338 	greth_clean_rings(greth);
339 	return -ENOMEM;
340 }
341 
342 static int greth_open(struct net_device *dev)
343 {
344 	struct greth_private *greth = netdev_priv(dev);
345 	int err;
346 
347 	err = greth_init_rings(greth);
348 	if (err) {
349 		if (netif_msg_ifup(greth))
350 			dev_err(&dev->dev, "Could not allocate memory for DMA rings\n");
351 		return err;
352 	}
353 
354 	err = request_irq(greth->irq, greth_interrupt, 0, "eth", (void *) dev);
355 	if (err) {
356 		if (netif_msg_ifup(greth))
357 			dev_err(&dev->dev, "Could not allocate interrupt %d\n", dev->irq);
358 		greth_clean_rings(greth);
359 		return err;
360 	}
361 
362 	if (netif_msg_ifup(greth))
363 		dev_dbg(&dev->dev, " starting queue\n");
364 	netif_start_queue(dev);
365 
366 	GRETH_REGSAVE(greth->regs->status, 0xFF);
367 
368 	napi_enable(&greth->napi);
369 
370 	greth_enable_irqs(greth);
371 	greth_enable_tx(greth);
372 	greth_enable_rx(greth);
373 	return 0;
374 
375 }
376 
377 static int greth_close(struct net_device *dev)
378 {
379 	struct greth_private *greth = netdev_priv(dev);
380 
381 	napi_disable(&greth->napi);
382 
383 	greth_disable_irqs(greth);
384 	greth_disable_tx(greth);
385 	greth_disable_rx(greth);
386 
387 	netif_stop_queue(dev);
388 
389 	free_irq(greth->irq, (void *) dev);
390 
391 	greth_clean_rings(greth);
392 
393 	return 0;
394 }
395 
396 static netdev_tx_t
397 greth_start_xmit(struct sk_buff *skb, struct net_device *dev)
398 {
399 	struct greth_private *greth = netdev_priv(dev);
400 	struct greth_bd *bdp;
401 	int err = NETDEV_TX_OK;
402 	u32 status, dma_addr, ctrl;
403 	unsigned long flags;
404 
405 	/* Clean TX Ring */
406 	greth_clean_tx(greth->netdev);
407 
408 	if (unlikely(greth->tx_free <= 0)) {
409 		spin_lock_irqsave(&greth->devlock, flags);/*save from poll/irq*/
410 		ctrl = GRETH_REGLOAD(greth->regs->control);
411 		/* Enable TX IRQ only if not already in poll() routine */
412 		if (ctrl & GRETH_RXI)
413 			GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_TXI);
414 		netif_stop_queue(dev);
415 		spin_unlock_irqrestore(&greth->devlock, flags);
416 		return NETDEV_TX_BUSY;
417 	}
418 
419 	if (netif_msg_pktdata(greth))
420 		greth_print_tx_packet(skb);
421 
422 
423 	if (unlikely(skb->len > MAX_FRAME_SIZE)) {
424 		dev->stats.tx_errors++;
425 		goto out;
426 	}
427 
428 	bdp = greth->tx_bd_base + greth->tx_next;
429 	dma_addr = greth_read_bd(&bdp->addr);
430 
431 	memcpy((unsigned char *) phys_to_virt(dma_addr), skb->data, skb->len);
432 
433 	dma_sync_single_for_device(greth->dev, dma_addr, skb->len, DMA_TO_DEVICE);
434 
435 	status = GRETH_BD_EN | GRETH_BD_IE | (skb->len & GRETH_BD_LEN);
436 	greth->tx_bufs_length[greth->tx_next] = skb->len & GRETH_BD_LEN;
437 
438 	/* Wrap around descriptor ring */
439 	if (greth->tx_next == GRETH_TXBD_NUM_MASK) {
440 		status |= GRETH_BD_WR;
441 	}
442 
443 	greth->tx_next = NEXT_TX(greth->tx_next);
444 	greth->tx_free--;
445 
446 	/* Write descriptor control word and enable transmission */
447 	greth_write_bd(&bdp->stat, status);
448 	spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
449 	greth_enable_tx(greth);
450 	spin_unlock_irqrestore(&greth->devlock, flags);
451 
452 out:
453 	dev_kfree_skb(skb);
454 	return err;
455 }
456 
457 static inline u16 greth_num_free_bds(u16 tx_last, u16 tx_next)
458 {
459 	if (tx_next < tx_last)
460 		return (tx_last - tx_next) - 1;
461 	else
462 		return GRETH_TXBD_NUM - (tx_next - tx_last) - 1;
463 }
464 
465 static netdev_tx_t
466 greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
467 {
468 	struct greth_private *greth = netdev_priv(dev);
469 	struct greth_bd *bdp;
470 	u32 status, dma_addr;
471 	int curr_tx, nr_frags, i, err = NETDEV_TX_OK;
472 	unsigned long flags;
473 	u16 tx_last;
474 
475 	nr_frags = skb_shinfo(skb)->nr_frags;
476 	tx_last = greth->tx_last;
477 	rmb(); /* tx_last is updated by the poll task */
478 
479 	if (greth_num_free_bds(tx_last, greth->tx_next) < nr_frags + 1) {
480 		netif_stop_queue(dev);
481 		err = NETDEV_TX_BUSY;
482 		goto out;
483 	}
484 
485 	if (netif_msg_pktdata(greth))
486 		greth_print_tx_packet(skb);
487 
488 	if (unlikely(skb->len > MAX_FRAME_SIZE)) {
489 		dev->stats.tx_errors++;
490 		goto out;
491 	}
492 
493 	/* Save skb pointer. */
494 	greth->tx_skbuff[greth->tx_next] = skb;
495 
496 	/* Linear buf */
497 	if (nr_frags != 0)
498 		status = GRETH_TXBD_MORE;
499 	else
500 		status = GRETH_BD_IE;
501 
502 	if (skb->ip_summed == CHECKSUM_PARTIAL)
503 		status |= GRETH_TXBD_CSALL;
504 	status |= skb_headlen(skb) & GRETH_BD_LEN;
505 	if (greth->tx_next == GRETH_TXBD_NUM_MASK)
506 		status |= GRETH_BD_WR;
507 
508 
509 	bdp = greth->tx_bd_base + greth->tx_next;
510 	greth_write_bd(&bdp->stat, status);
511 	dma_addr = dma_map_single(greth->dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
512 
513 	if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
514 		goto map_error;
515 
516 	greth_write_bd(&bdp->addr, dma_addr);
517 
518 	curr_tx = NEXT_TX(greth->tx_next);
519 
520 	/* Frags */
521 	for (i = 0; i < nr_frags; i++) {
522 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
523 		greth->tx_skbuff[curr_tx] = NULL;
524 		bdp = greth->tx_bd_base + curr_tx;
525 
526 		status = GRETH_BD_EN;
527 		if (skb->ip_summed == CHECKSUM_PARTIAL)
528 			status |= GRETH_TXBD_CSALL;
529 		status |= skb_frag_size(frag) & GRETH_BD_LEN;
530 
531 		/* Wrap around descriptor ring */
532 		if (curr_tx == GRETH_TXBD_NUM_MASK)
533 			status |= GRETH_BD_WR;
534 
535 		/* More fragments left */
536 		if (i < nr_frags - 1)
537 			status |= GRETH_TXBD_MORE;
538 		else
539 			status |= GRETH_BD_IE; /* enable IRQ on last fragment */
540 
541 		greth_write_bd(&bdp->stat, status);
542 
543 		dma_addr = skb_frag_dma_map(greth->dev, frag, 0, skb_frag_size(frag),
544 					    DMA_TO_DEVICE);
545 
546 		if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
547 			goto frag_map_error;
548 
549 		greth_write_bd(&bdp->addr, dma_addr);
550 
551 		curr_tx = NEXT_TX(curr_tx);
552 	}
553 
554 	wmb();
555 
556 	/* Enable the descriptor chain by enabling the first descriptor */
557 	bdp = greth->tx_bd_base + greth->tx_next;
558 	greth_write_bd(&bdp->stat,
559 		       greth_read_bd(&bdp->stat) | GRETH_BD_EN);
560 
561 	spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
562 	greth->tx_next = curr_tx;
563 	greth_enable_tx_and_irq(greth);
564 	spin_unlock_irqrestore(&greth->devlock, flags);
565 
566 	return NETDEV_TX_OK;
567 
568 frag_map_error:
569 	/* Unmap SKB mappings that succeeded and disable descriptor */
570 	for (i = 0; greth->tx_next + i != curr_tx; i++) {
571 		bdp = greth->tx_bd_base + greth->tx_next + i;
572 		dma_unmap_single(greth->dev,
573 				 greth_read_bd(&bdp->addr),
574 				 greth_read_bd(&bdp->stat) & GRETH_BD_LEN,
575 				 DMA_TO_DEVICE);
576 		greth_write_bd(&bdp->stat, 0);
577 	}
578 map_error:
579 	if (net_ratelimit())
580 		dev_warn(greth->dev, "Could not create TX DMA mapping\n");
581 	dev_kfree_skb(skb);
582 out:
583 	return err;
584 }
585 
586 static irqreturn_t greth_interrupt(int irq, void *dev_id)
587 {
588 	struct net_device *dev = dev_id;
589 	struct greth_private *greth;
590 	u32 status, ctrl;
591 	irqreturn_t retval = IRQ_NONE;
592 
593 	greth = netdev_priv(dev);
594 
595 	spin_lock(&greth->devlock);
596 
597 	/* Get the interrupt events that caused us to be here. */
598 	status = GRETH_REGLOAD(greth->regs->status);
599 
600 	/* Must see if interrupts are enabled also, INT_TX|INT_RX flags may be
601 	 * set regardless of whether IRQ is enabled or not. Especially
602 	 * important when shared IRQ.
603 	 */
604 	ctrl = GRETH_REGLOAD(greth->regs->control);
605 
606 	/* Handle rx and tx interrupts through poll */
607 	if (((status & (GRETH_INT_RE | GRETH_INT_RX)) && (ctrl & GRETH_RXI)) ||
608 	    ((status & (GRETH_INT_TE | GRETH_INT_TX)) && (ctrl & GRETH_TXI))) {
609 		retval = IRQ_HANDLED;
610 
611 		/* Disable interrupts and schedule poll() */
612 		greth_disable_irqs(greth);
613 		napi_schedule(&greth->napi);
614 	}
615 
616 	mmiowb();
617 	spin_unlock(&greth->devlock);
618 
619 	return retval;
620 }
621 
622 static void greth_clean_tx(struct net_device *dev)
623 {
624 	struct greth_private *greth;
625 	struct greth_bd *bdp;
626 	u32 stat;
627 
628 	greth = netdev_priv(dev);
629 
630 	while (1) {
631 		bdp = greth->tx_bd_base + greth->tx_last;
632 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
633 		mb();
634 		stat = greth_read_bd(&bdp->stat);
635 
636 		if (unlikely(stat & GRETH_BD_EN))
637 			break;
638 
639 		if (greth->tx_free == GRETH_TXBD_NUM)
640 			break;
641 
642 		/* Check status for errors */
643 		if (unlikely(stat & GRETH_TXBD_STATUS)) {
644 			dev->stats.tx_errors++;
645 			if (stat & GRETH_TXBD_ERR_AL)
646 				dev->stats.tx_aborted_errors++;
647 			if (stat & GRETH_TXBD_ERR_UE)
648 				dev->stats.tx_fifo_errors++;
649 		}
650 		dev->stats.tx_packets++;
651 		dev->stats.tx_bytes += greth->tx_bufs_length[greth->tx_last];
652 		greth->tx_last = NEXT_TX(greth->tx_last);
653 		greth->tx_free++;
654 	}
655 
656 	if (greth->tx_free > 0) {
657 		netif_wake_queue(dev);
658 	}
659 }
660 
661 static inline void greth_update_tx_stats(struct net_device *dev, u32 stat)
662 {
663 	/* Check status for errors */
664 	if (unlikely(stat & GRETH_TXBD_STATUS)) {
665 		dev->stats.tx_errors++;
666 		if (stat & GRETH_TXBD_ERR_AL)
667 			dev->stats.tx_aborted_errors++;
668 		if (stat & GRETH_TXBD_ERR_UE)
669 			dev->stats.tx_fifo_errors++;
670 		if (stat & GRETH_TXBD_ERR_LC)
671 			dev->stats.tx_aborted_errors++;
672 	}
673 	dev->stats.tx_packets++;
674 }
675 
676 static void greth_clean_tx_gbit(struct net_device *dev)
677 {
678 	struct greth_private *greth;
679 	struct greth_bd *bdp, *bdp_last_frag;
680 	struct sk_buff *skb = NULL;
681 	u32 stat;
682 	int nr_frags, i;
683 	u16 tx_last;
684 
685 	greth = netdev_priv(dev);
686 	tx_last = greth->tx_last;
687 
688 	while (tx_last != greth->tx_next) {
689 
690 		skb = greth->tx_skbuff[tx_last];
691 
692 		nr_frags = skb_shinfo(skb)->nr_frags;
693 
694 		/* We only clean fully completed SKBs */
695 		bdp_last_frag = greth->tx_bd_base + SKIP_TX(tx_last, nr_frags);
696 
697 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
698 		mb();
699 		stat = greth_read_bd(&bdp_last_frag->stat);
700 
701 		if (stat & GRETH_BD_EN)
702 			break;
703 
704 		greth->tx_skbuff[tx_last] = NULL;
705 
706 		greth_update_tx_stats(dev, stat);
707 		dev->stats.tx_bytes += skb->len;
708 
709 		bdp = greth->tx_bd_base + tx_last;
710 
711 		tx_last = NEXT_TX(tx_last);
712 
713 		dma_unmap_single(greth->dev,
714 				 greth_read_bd(&bdp->addr),
715 				 skb_headlen(skb),
716 				 DMA_TO_DEVICE);
717 
718 		for (i = 0; i < nr_frags; i++) {
719 			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
720 			bdp = greth->tx_bd_base + tx_last;
721 
722 			dma_unmap_page(greth->dev,
723 				       greth_read_bd(&bdp->addr),
724 				       skb_frag_size(frag),
725 				       DMA_TO_DEVICE);
726 
727 			tx_last = NEXT_TX(tx_last);
728 		}
729 		dev_kfree_skb(skb);
730 	}
731 	if (skb) { /* skb is set only if the above while loop was entered */
732 		wmb();
733 		greth->tx_last = tx_last;
734 
735 		if (netif_queue_stopped(dev) &&
736 		    (greth_num_free_bds(tx_last, greth->tx_next) >
737 		    (MAX_SKB_FRAGS+1)))
738 			netif_wake_queue(dev);
739 	}
740 }
741 
742 static int greth_rx(struct net_device *dev, int limit)
743 {
744 	struct greth_private *greth;
745 	struct greth_bd *bdp;
746 	struct sk_buff *skb;
747 	int pkt_len;
748 	int bad, count;
749 	u32 status, dma_addr;
750 	unsigned long flags;
751 
752 	greth = netdev_priv(dev);
753 
754 	for (count = 0; count < limit; ++count) {
755 
756 		bdp = greth->rx_bd_base + greth->rx_cur;
757 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
758 		mb();
759 		status = greth_read_bd(&bdp->stat);
760 
761 		if (unlikely(status & GRETH_BD_EN)) {
762 			break;
763 		}
764 
765 		dma_addr = greth_read_bd(&bdp->addr);
766 		bad = 0;
767 
768 		/* Check status for errors. */
769 		if (unlikely(status & GRETH_RXBD_STATUS)) {
770 			if (status & GRETH_RXBD_ERR_FT) {
771 				dev->stats.rx_length_errors++;
772 				bad = 1;
773 			}
774 			if (status & (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE)) {
775 				dev->stats.rx_frame_errors++;
776 				bad = 1;
777 			}
778 			if (status & GRETH_RXBD_ERR_CRC) {
779 				dev->stats.rx_crc_errors++;
780 				bad = 1;
781 			}
782 		}
783 		if (unlikely(bad)) {
784 			dev->stats.rx_errors++;
785 
786 		} else {
787 
788 			pkt_len = status & GRETH_BD_LEN;
789 
790 			skb = netdev_alloc_skb(dev, pkt_len + NET_IP_ALIGN);
791 
792 			if (unlikely(skb == NULL)) {
793 
794 				if (net_ratelimit())
795 					dev_warn(&dev->dev, "low on memory - " "packet dropped\n");
796 
797 				dev->stats.rx_dropped++;
798 
799 			} else {
800 				skb_reserve(skb, NET_IP_ALIGN);
801 
802 				dma_sync_single_for_cpu(greth->dev,
803 							dma_addr,
804 							pkt_len,
805 							DMA_FROM_DEVICE);
806 
807 				if (netif_msg_pktdata(greth))
808 					greth_print_rx_packet(phys_to_virt(dma_addr), pkt_len);
809 
810 				skb_put_data(skb, phys_to_virt(dma_addr),
811 					     pkt_len);
812 
813 				skb->protocol = eth_type_trans(skb, dev);
814 				dev->stats.rx_bytes += pkt_len;
815 				dev->stats.rx_packets++;
816 				netif_receive_skb(skb);
817 			}
818 		}
819 
820 		status = GRETH_BD_EN | GRETH_BD_IE;
821 		if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
822 			status |= GRETH_BD_WR;
823 		}
824 
825 		wmb();
826 		greth_write_bd(&bdp->stat, status);
827 
828 		dma_sync_single_for_device(greth->dev, dma_addr, MAX_FRAME_SIZE, DMA_FROM_DEVICE);
829 
830 		spin_lock_irqsave(&greth->devlock, flags); /* save from XMIT */
831 		greth_enable_rx(greth);
832 		spin_unlock_irqrestore(&greth->devlock, flags);
833 
834 		greth->rx_cur = NEXT_RX(greth->rx_cur);
835 	}
836 
837 	return count;
838 }
839 
840 static inline int hw_checksummed(u32 status)
841 {
842 
843 	if (status & GRETH_RXBD_IP_FRAG)
844 		return 0;
845 
846 	if (status & GRETH_RXBD_IP && status & GRETH_RXBD_IP_CSERR)
847 		return 0;
848 
849 	if (status & GRETH_RXBD_UDP && status & GRETH_RXBD_UDP_CSERR)
850 		return 0;
851 
852 	if (status & GRETH_RXBD_TCP && status & GRETH_RXBD_TCP_CSERR)
853 		return 0;
854 
855 	return 1;
856 }
857 
858 static int greth_rx_gbit(struct net_device *dev, int limit)
859 {
860 	struct greth_private *greth;
861 	struct greth_bd *bdp;
862 	struct sk_buff *skb, *newskb;
863 	int pkt_len;
864 	int bad, count = 0;
865 	u32 status, dma_addr;
866 	unsigned long flags;
867 
868 	greth = netdev_priv(dev);
869 
870 	for (count = 0; count < limit; ++count) {
871 
872 		bdp = greth->rx_bd_base + greth->rx_cur;
873 		skb = greth->rx_skbuff[greth->rx_cur];
874 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
875 		mb();
876 		status = greth_read_bd(&bdp->stat);
877 		bad = 0;
878 
879 		if (status & GRETH_BD_EN)
880 			break;
881 
882 		/* Check status for errors. */
883 		if (unlikely(status & GRETH_RXBD_STATUS)) {
884 
885 			if (status & GRETH_RXBD_ERR_FT) {
886 				dev->stats.rx_length_errors++;
887 				bad = 1;
888 			} else if (status &
889 				   (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE | GRETH_RXBD_ERR_LE)) {
890 				dev->stats.rx_frame_errors++;
891 				bad = 1;
892 			} else if (status & GRETH_RXBD_ERR_CRC) {
893 				dev->stats.rx_crc_errors++;
894 				bad = 1;
895 			}
896 		}
897 
898 		/* Allocate new skb to replace current, not needed if the
899 		 * current skb can be reused */
900 		if (!bad && (newskb=netdev_alloc_skb(dev, MAX_FRAME_SIZE + NET_IP_ALIGN))) {
901 			skb_reserve(newskb, NET_IP_ALIGN);
902 
903 			dma_addr = dma_map_single(greth->dev,
904 						      newskb->data,
905 						      MAX_FRAME_SIZE + NET_IP_ALIGN,
906 						      DMA_FROM_DEVICE);
907 
908 			if (!dma_mapping_error(greth->dev, dma_addr)) {
909 				/* Process the incoming frame. */
910 				pkt_len = status & GRETH_BD_LEN;
911 
912 				dma_unmap_single(greth->dev,
913 						 greth_read_bd(&bdp->addr),
914 						 MAX_FRAME_SIZE + NET_IP_ALIGN,
915 						 DMA_FROM_DEVICE);
916 
917 				if (netif_msg_pktdata(greth))
918 					greth_print_rx_packet(phys_to_virt(greth_read_bd(&bdp->addr)), pkt_len);
919 
920 				skb_put(skb, pkt_len);
921 
922 				if (dev->features & NETIF_F_RXCSUM && hw_checksummed(status))
923 					skb->ip_summed = CHECKSUM_UNNECESSARY;
924 				else
925 					skb_checksum_none_assert(skb);
926 
927 				skb->protocol = eth_type_trans(skb, dev);
928 				dev->stats.rx_packets++;
929 				dev->stats.rx_bytes += pkt_len;
930 				netif_receive_skb(skb);
931 
932 				greth->rx_skbuff[greth->rx_cur] = newskb;
933 				greth_write_bd(&bdp->addr, dma_addr);
934 			} else {
935 				if (net_ratelimit())
936 					dev_warn(greth->dev, "Could not create DMA mapping, dropping packet\n");
937 				dev_kfree_skb(newskb);
938 				/* reusing current skb, so it is a drop */
939 				dev->stats.rx_dropped++;
940 			}
941 		} else if (bad) {
942 			/* Bad Frame transfer, the skb is reused */
943 			dev->stats.rx_dropped++;
944 		} else {
945 			/* Failed Allocating a new skb. This is rather stupid
946 			 * but the current "filled" skb is reused, as if
947 			 * transfer failure. One could argue that RX descriptor
948 			 * table handling should be divided into cleaning and
949 			 * filling as the TX part of the driver
950 			 */
951 			if (net_ratelimit())
952 				dev_warn(greth->dev, "Could not allocate SKB, dropping packet\n");
953 			/* reusing current skb, so it is a drop */
954 			dev->stats.rx_dropped++;
955 		}
956 
957 		status = GRETH_BD_EN | GRETH_BD_IE;
958 		if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
959 			status |= GRETH_BD_WR;
960 		}
961 
962 		wmb();
963 		greth_write_bd(&bdp->stat, status);
964 		spin_lock_irqsave(&greth->devlock, flags);
965 		greth_enable_rx(greth);
966 		spin_unlock_irqrestore(&greth->devlock, flags);
967 		greth->rx_cur = NEXT_RX(greth->rx_cur);
968 	}
969 
970 	return count;
971 
972 }
973 
974 static int greth_poll(struct napi_struct *napi, int budget)
975 {
976 	struct greth_private *greth;
977 	int work_done = 0;
978 	unsigned long flags;
979 	u32 mask, ctrl;
980 	greth = container_of(napi, struct greth_private, napi);
981 
982 restart_txrx_poll:
983 	if (greth->gbit_mac) {
984 		greth_clean_tx_gbit(greth->netdev);
985 		work_done += greth_rx_gbit(greth->netdev, budget - work_done);
986 	} else {
987 		if (netif_queue_stopped(greth->netdev))
988 			greth_clean_tx(greth->netdev);
989 		work_done += greth_rx(greth->netdev, budget - work_done);
990 	}
991 
992 	if (work_done < budget) {
993 
994 		spin_lock_irqsave(&greth->devlock, flags);
995 
996 		ctrl = GRETH_REGLOAD(greth->regs->control);
997 		if ((greth->gbit_mac && (greth->tx_last != greth->tx_next)) ||
998 		    (!greth->gbit_mac && netif_queue_stopped(greth->netdev))) {
999 			GRETH_REGSAVE(greth->regs->control,
1000 					ctrl | GRETH_TXI | GRETH_RXI);
1001 			mask = GRETH_INT_RX | GRETH_INT_RE |
1002 			       GRETH_INT_TX | GRETH_INT_TE;
1003 		} else {
1004 			GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_RXI);
1005 			mask = GRETH_INT_RX | GRETH_INT_RE;
1006 		}
1007 
1008 		if (GRETH_REGLOAD(greth->regs->status) & mask) {
1009 			GRETH_REGSAVE(greth->regs->control, ctrl);
1010 			spin_unlock_irqrestore(&greth->devlock, flags);
1011 			goto restart_txrx_poll;
1012 		} else {
1013 			napi_complete_done(napi, work_done);
1014 			spin_unlock_irqrestore(&greth->devlock, flags);
1015 		}
1016 	}
1017 
1018 	return work_done;
1019 }
1020 
1021 static int greth_set_mac_add(struct net_device *dev, void *p)
1022 {
1023 	struct sockaddr *addr = p;
1024 	struct greth_private *greth;
1025 	struct greth_regs *regs;
1026 
1027 	greth = netdev_priv(dev);
1028 	regs = greth->regs;
1029 
1030 	if (!is_valid_ether_addr(addr->sa_data))
1031 		return -EADDRNOTAVAIL;
1032 
1033 	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
1034 	GRETH_REGSAVE(regs->esa_msb, dev->dev_addr[0] << 8 | dev->dev_addr[1]);
1035 	GRETH_REGSAVE(regs->esa_lsb, dev->dev_addr[2] << 24 | dev->dev_addr[3] << 16 |
1036 		      dev->dev_addr[4] << 8 | dev->dev_addr[5]);
1037 
1038 	return 0;
1039 }
1040 
1041 static u32 greth_hash_get_index(__u8 *addr)
1042 {
1043 	return (ether_crc(6, addr)) & 0x3F;
1044 }
1045 
1046 static void greth_set_hash_filter(struct net_device *dev)
1047 {
1048 	struct netdev_hw_addr *ha;
1049 	struct greth_private *greth = netdev_priv(dev);
1050 	struct greth_regs *regs = greth->regs;
1051 	u32 mc_filter[2];
1052 	unsigned int bitnr;
1053 
1054 	mc_filter[0] = mc_filter[1] = 0;
1055 
1056 	netdev_for_each_mc_addr(ha, dev) {
1057 		bitnr = greth_hash_get_index(ha->addr);
1058 		mc_filter[bitnr >> 5] |= 1 << (bitnr & 31);
1059 	}
1060 
1061 	GRETH_REGSAVE(regs->hash_msb, mc_filter[1]);
1062 	GRETH_REGSAVE(regs->hash_lsb, mc_filter[0]);
1063 }
1064 
1065 static void greth_set_multicast_list(struct net_device *dev)
1066 {
1067 	int cfg;
1068 	struct greth_private *greth = netdev_priv(dev);
1069 	struct greth_regs *regs = greth->regs;
1070 
1071 	cfg = GRETH_REGLOAD(regs->control);
1072 	if (dev->flags & IFF_PROMISC)
1073 		cfg |= GRETH_CTRL_PR;
1074 	else
1075 		cfg &= ~GRETH_CTRL_PR;
1076 
1077 	if (greth->multicast) {
1078 		if (dev->flags & IFF_ALLMULTI) {
1079 			GRETH_REGSAVE(regs->hash_msb, -1);
1080 			GRETH_REGSAVE(regs->hash_lsb, -1);
1081 			cfg |= GRETH_CTRL_MCEN;
1082 			GRETH_REGSAVE(regs->control, cfg);
1083 			return;
1084 		}
1085 
1086 		if (netdev_mc_empty(dev)) {
1087 			cfg &= ~GRETH_CTRL_MCEN;
1088 			GRETH_REGSAVE(regs->control, cfg);
1089 			return;
1090 		}
1091 
1092 		/* Setup multicast filter */
1093 		greth_set_hash_filter(dev);
1094 		cfg |= GRETH_CTRL_MCEN;
1095 	}
1096 	GRETH_REGSAVE(regs->control, cfg);
1097 }
1098 
1099 static u32 greth_get_msglevel(struct net_device *dev)
1100 {
1101 	struct greth_private *greth = netdev_priv(dev);
1102 	return greth->msg_enable;
1103 }
1104 
1105 static void greth_set_msglevel(struct net_device *dev, u32 value)
1106 {
1107 	struct greth_private *greth = netdev_priv(dev);
1108 	greth->msg_enable = value;
1109 }
1110 
1111 static int greth_get_regs_len(struct net_device *dev)
1112 {
1113 	return sizeof(struct greth_regs);
1114 }
1115 
1116 static void greth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1117 {
1118 	struct greth_private *greth = netdev_priv(dev);
1119 
1120 	strlcpy(info->driver, dev_driver_string(greth->dev),
1121 		sizeof(info->driver));
1122 	strlcpy(info->version, "revision: 1.0", sizeof(info->version));
1123 	strlcpy(info->bus_info, greth->dev->bus->name, sizeof(info->bus_info));
1124 	strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
1125 }
1126 
1127 static void greth_get_regs(struct net_device *dev, struct ethtool_regs *regs, void *p)
1128 {
1129 	int i;
1130 	struct greth_private *greth = netdev_priv(dev);
1131 	u32 __iomem *greth_regs = (u32 __iomem *) greth->regs;
1132 	u32 *buff = p;
1133 
1134 	for (i = 0; i < sizeof(struct greth_regs) / sizeof(u32); i++)
1135 		buff[i] = greth_read_bd(&greth_regs[i]);
1136 }
1137 
1138 static const struct ethtool_ops greth_ethtool_ops = {
1139 	.get_msglevel		= greth_get_msglevel,
1140 	.set_msglevel		= greth_set_msglevel,
1141 	.get_drvinfo		= greth_get_drvinfo,
1142 	.get_regs_len           = greth_get_regs_len,
1143 	.get_regs               = greth_get_regs,
1144 	.get_link		= ethtool_op_get_link,
1145 	.get_link_ksettings	= phy_ethtool_get_link_ksettings,
1146 	.set_link_ksettings	= phy_ethtool_set_link_ksettings,
1147 };
1148 
1149 static struct net_device_ops greth_netdev_ops = {
1150 	.ndo_open		= greth_open,
1151 	.ndo_stop		= greth_close,
1152 	.ndo_start_xmit		= greth_start_xmit,
1153 	.ndo_set_mac_address	= greth_set_mac_add,
1154 	.ndo_validate_addr	= eth_validate_addr,
1155 };
1156 
1157 static inline int wait_for_mdio(struct greth_private *greth)
1158 {
1159 	unsigned long timeout = jiffies + 4*HZ/100;
1160 	while (GRETH_REGLOAD(greth->regs->mdio) & GRETH_MII_BUSY) {
1161 		if (time_after(jiffies, timeout))
1162 			return 0;
1163 	}
1164 	return 1;
1165 }
1166 
1167 static int greth_mdio_read(struct mii_bus *bus, int phy, int reg)
1168 {
1169 	struct greth_private *greth = bus->priv;
1170 	int data;
1171 
1172 	if (!wait_for_mdio(greth))
1173 		return -EBUSY;
1174 
1175 	GRETH_REGSAVE(greth->regs->mdio, ((phy & 0x1F) << 11) | ((reg & 0x1F) << 6) | 2);
1176 
1177 	if (!wait_for_mdio(greth))
1178 		return -EBUSY;
1179 
1180 	if (!(GRETH_REGLOAD(greth->regs->mdio) & GRETH_MII_NVALID)) {
1181 		data = (GRETH_REGLOAD(greth->regs->mdio) >> 16) & 0xFFFF;
1182 		return data;
1183 
1184 	} else {
1185 		return -1;
1186 	}
1187 }
1188 
1189 static int greth_mdio_write(struct mii_bus *bus, int phy, int reg, u16 val)
1190 {
1191 	struct greth_private *greth = bus->priv;
1192 
1193 	if (!wait_for_mdio(greth))
1194 		return -EBUSY;
1195 
1196 	GRETH_REGSAVE(greth->regs->mdio,
1197 		      ((val & 0xFFFF) << 16) | ((phy & 0x1F) << 11) | ((reg & 0x1F) << 6) | 1);
1198 
1199 	if (!wait_for_mdio(greth))
1200 		return -EBUSY;
1201 
1202 	return 0;
1203 }
1204 
1205 static void greth_link_change(struct net_device *dev)
1206 {
1207 	struct greth_private *greth = netdev_priv(dev);
1208 	struct phy_device *phydev = dev->phydev;
1209 	unsigned long flags;
1210 	int status_change = 0;
1211 	u32 ctrl;
1212 
1213 	spin_lock_irqsave(&greth->devlock, flags);
1214 
1215 	if (phydev->link) {
1216 
1217 		if ((greth->speed != phydev->speed) || (greth->duplex != phydev->duplex)) {
1218 			ctrl = GRETH_REGLOAD(greth->regs->control) &
1219 			       ~(GRETH_CTRL_FD | GRETH_CTRL_SP | GRETH_CTRL_GB);
1220 
1221 			if (phydev->duplex)
1222 				ctrl |= GRETH_CTRL_FD;
1223 
1224 			if (phydev->speed == SPEED_100)
1225 				ctrl |= GRETH_CTRL_SP;
1226 			else if (phydev->speed == SPEED_1000)
1227 				ctrl |= GRETH_CTRL_GB;
1228 
1229 			GRETH_REGSAVE(greth->regs->control, ctrl);
1230 			greth->speed = phydev->speed;
1231 			greth->duplex = phydev->duplex;
1232 			status_change = 1;
1233 		}
1234 	}
1235 
1236 	if (phydev->link != greth->link) {
1237 		if (!phydev->link) {
1238 			greth->speed = 0;
1239 			greth->duplex = -1;
1240 		}
1241 		greth->link = phydev->link;
1242 
1243 		status_change = 1;
1244 	}
1245 
1246 	spin_unlock_irqrestore(&greth->devlock, flags);
1247 
1248 	if (status_change) {
1249 		if (phydev->link)
1250 			pr_debug("%s: link up (%d/%s)\n",
1251 				dev->name, phydev->speed,
1252 				DUPLEX_FULL == phydev->duplex ? "Full" : "Half");
1253 		else
1254 			pr_debug("%s: link down\n", dev->name);
1255 	}
1256 }
1257 
1258 static int greth_mdio_probe(struct net_device *dev)
1259 {
1260 	struct greth_private *greth = netdev_priv(dev);
1261 	struct phy_device *phy = NULL;
1262 	int ret;
1263 
1264 	/* Find the first PHY */
1265 	phy = phy_find_first(greth->mdio);
1266 
1267 	if (!phy) {
1268 		if (netif_msg_probe(greth))
1269 			dev_err(&dev->dev, "no PHY found\n");
1270 		return -ENXIO;
1271 	}
1272 
1273 	ret = phy_connect_direct(dev, phy, &greth_link_change,
1274 				 greth->gbit_mac ? PHY_INTERFACE_MODE_GMII : PHY_INTERFACE_MODE_MII);
1275 	if (ret) {
1276 		if (netif_msg_ifup(greth))
1277 			dev_err(&dev->dev, "could not attach to PHY\n");
1278 		return ret;
1279 	}
1280 
1281 	if (greth->gbit_mac)
1282 		phy_set_max_speed(phy, SPEED_1000);
1283 	else
1284 		phy_set_max_speed(phy, SPEED_100);
1285 
1286 	linkmode_copy(phy->advertising, phy->supported);
1287 
1288 	greth->link = 0;
1289 	greth->speed = 0;
1290 	greth->duplex = -1;
1291 
1292 	return 0;
1293 }
1294 
1295 static int greth_mdio_init(struct greth_private *greth)
1296 {
1297 	int ret;
1298 	unsigned long timeout;
1299 	struct net_device *ndev = greth->netdev;
1300 
1301 	greth->mdio = mdiobus_alloc();
1302 	if (!greth->mdio) {
1303 		return -ENOMEM;
1304 	}
1305 
1306 	greth->mdio->name = "greth-mdio";
1307 	snprintf(greth->mdio->id, MII_BUS_ID_SIZE, "%s-%d", greth->mdio->name, greth->irq);
1308 	greth->mdio->read = greth_mdio_read;
1309 	greth->mdio->write = greth_mdio_write;
1310 	greth->mdio->priv = greth;
1311 
1312 	ret = mdiobus_register(greth->mdio);
1313 	if (ret) {
1314 		goto error;
1315 	}
1316 
1317 	ret = greth_mdio_probe(greth->netdev);
1318 	if (ret) {
1319 		if (netif_msg_probe(greth))
1320 			dev_err(&greth->netdev->dev, "failed to probe MDIO bus\n");
1321 		goto unreg_mdio;
1322 	}
1323 
1324 	phy_start(ndev->phydev);
1325 
1326 	/* If Ethernet debug link is used make autoneg happen right away */
1327 	if (greth->edcl && greth_edcl == 1) {
1328 		phy_start_aneg(ndev->phydev);
1329 		timeout = jiffies + 6*HZ;
1330 		while (!phy_aneg_done(ndev->phydev) &&
1331 		       time_before(jiffies, timeout)) {
1332 		}
1333 		phy_read_status(ndev->phydev);
1334 		greth_link_change(greth->netdev);
1335 	}
1336 
1337 	return 0;
1338 
1339 unreg_mdio:
1340 	mdiobus_unregister(greth->mdio);
1341 error:
1342 	mdiobus_free(greth->mdio);
1343 	return ret;
1344 }
1345 
1346 /* Initialize the GRETH MAC */
1347 static int greth_of_probe(struct platform_device *ofdev)
1348 {
1349 	struct net_device *dev;
1350 	struct greth_private *greth;
1351 	struct greth_regs *regs;
1352 
1353 	int i;
1354 	int err;
1355 	int tmp;
1356 	unsigned long timeout;
1357 
1358 	dev = alloc_etherdev(sizeof(struct greth_private));
1359 
1360 	if (dev == NULL)
1361 		return -ENOMEM;
1362 
1363 	greth = netdev_priv(dev);
1364 	greth->netdev = dev;
1365 	greth->dev = &ofdev->dev;
1366 
1367 	if (greth_debug > 0)
1368 		greth->msg_enable = greth_debug;
1369 	else
1370 		greth->msg_enable = GRETH_DEF_MSG_ENABLE;
1371 
1372 	spin_lock_init(&greth->devlock);
1373 
1374 	greth->regs = of_ioremap(&ofdev->resource[0], 0,
1375 				 resource_size(&ofdev->resource[0]),
1376 				 "grlib-greth regs");
1377 
1378 	if (greth->regs == NULL) {
1379 		if (netif_msg_probe(greth))
1380 			dev_err(greth->dev, "ioremap failure.\n");
1381 		err = -EIO;
1382 		goto error1;
1383 	}
1384 
1385 	regs = greth->regs;
1386 	greth->irq = ofdev->archdata.irqs[0];
1387 
1388 	dev_set_drvdata(greth->dev, dev);
1389 	SET_NETDEV_DEV(dev, greth->dev);
1390 
1391 	if (netif_msg_probe(greth))
1392 		dev_dbg(greth->dev, "resetting controller.\n");
1393 
1394 	/* Reset the controller. */
1395 	GRETH_REGSAVE(regs->control, GRETH_RESET);
1396 
1397 	/* Wait for MAC to reset itself */
1398 	timeout = jiffies + HZ/100;
1399 	while (GRETH_REGLOAD(regs->control) & GRETH_RESET) {
1400 		if (time_after(jiffies, timeout)) {
1401 			err = -EIO;
1402 			if (netif_msg_probe(greth))
1403 				dev_err(greth->dev, "timeout when waiting for reset.\n");
1404 			goto error2;
1405 		}
1406 	}
1407 
1408 	/* Get default PHY address  */
1409 	greth->phyaddr = (GRETH_REGLOAD(regs->mdio) >> 11) & 0x1F;
1410 
1411 	/* Check if we have GBIT capable MAC */
1412 	tmp = GRETH_REGLOAD(regs->control);
1413 	greth->gbit_mac = (tmp >> 27) & 1;
1414 
1415 	/* Check for multicast capability */
1416 	greth->multicast = (tmp >> 25) & 1;
1417 
1418 	greth->edcl = (tmp >> 31) & 1;
1419 
1420 	/* If we have EDCL we disable the EDCL speed-duplex FSM so
1421 	 * it doesn't interfere with the software */
1422 	if (greth->edcl != 0)
1423 		GRETH_REGORIN(regs->control, GRETH_CTRL_DISDUPLEX);
1424 
1425 	/* Check if MAC can handle MDIO interrupts */
1426 	greth->mdio_int_en = (tmp >> 26) & 1;
1427 
1428 	err = greth_mdio_init(greth);
1429 	if (err) {
1430 		if (netif_msg_probe(greth))
1431 			dev_err(greth->dev, "failed to register MDIO bus\n");
1432 		goto error2;
1433 	}
1434 
1435 	/* Allocate TX descriptor ring in coherent memory */
1436 	greth->tx_bd_base = dma_zalloc_coherent(greth->dev, 1024,
1437 						&greth->tx_bd_base_phys,
1438 						GFP_KERNEL);
1439 	if (!greth->tx_bd_base) {
1440 		err = -ENOMEM;
1441 		goto error3;
1442 	}
1443 
1444 	/* Allocate RX descriptor ring in coherent memory */
1445 	greth->rx_bd_base = dma_zalloc_coherent(greth->dev, 1024,
1446 						&greth->rx_bd_base_phys,
1447 						GFP_KERNEL);
1448 	if (!greth->rx_bd_base) {
1449 		err = -ENOMEM;
1450 		goto error4;
1451 	}
1452 
1453 	/* Get MAC address from: module param, OF property or ID prom */
1454 	for (i = 0; i < 6; i++) {
1455 		if (macaddr[i] != 0)
1456 			break;
1457 	}
1458 	if (i == 6) {
1459 		const u8 *addr;
1460 
1461 		addr = of_get_mac_address(ofdev->dev.of_node);
1462 		if (addr) {
1463 			for (i = 0; i < 6; i++)
1464 				macaddr[i] = (unsigned int) addr[i];
1465 		} else {
1466 #ifdef CONFIG_SPARC
1467 			for (i = 0; i < 6; i++)
1468 				macaddr[i] = (unsigned int) idprom->id_ethaddr[i];
1469 #endif
1470 		}
1471 	}
1472 
1473 	for (i = 0; i < 6; i++)
1474 		dev->dev_addr[i] = macaddr[i];
1475 
1476 	macaddr[5]++;
1477 
1478 	if (!is_valid_ether_addr(&dev->dev_addr[0])) {
1479 		if (netif_msg_probe(greth))
1480 			dev_err(greth->dev, "no valid ethernet address, aborting.\n");
1481 		err = -EINVAL;
1482 		goto error5;
1483 	}
1484 
1485 	GRETH_REGSAVE(regs->esa_msb, dev->dev_addr[0] << 8 | dev->dev_addr[1]);
1486 	GRETH_REGSAVE(regs->esa_lsb, dev->dev_addr[2] << 24 | dev->dev_addr[3] << 16 |
1487 		      dev->dev_addr[4] << 8 | dev->dev_addr[5]);
1488 
1489 	/* Clear all pending interrupts except PHY irq */
1490 	GRETH_REGSAVE(regs->status, 0xFF);
1491 
1492 	if (greth->gbit_mac) {
1493 		dev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM |
1494 			NETIF_F_RXCSUM;
1495 		dev->features = dev->hw_features | NETIF_F_HIGHDMA;
1496 		greth_netdev_ops.ndo_start_xmit = greth_start_xmit_gbit;
1497 	}
1498 
1499 	if (greth->multicast) {
1500 		greth_netdev_ops.ndo_set_rx_mode = greth_set_multicast_list;
1501 		dev->flags |= IFF_MULTICAST;
1502 	} else {
1503 		dev->flags &= ~IFF_MULTICAST;
1504 	}
1505 
1506 	dev->netdev_ops = &greth_netdev_ops;
1507 	dev->ethtool_ops = &greth_ethtool_ops;
1508 
1509 	err = register_netdev(dev);
1510 	if (err) {
1511 		if (netif_msg_probe(greth))
1512 			dev_err(greth->dev, "netdevice registration failed.\n");
1513 		goto error5;
1514 	}
1515 
1516 	/* setup NAPI */
1517 	netif_napi_add(dev, &greth->napi, greth_poll, 64);
1518 
1519 	return 0;
1520 
1521 error5:
1522 	dma_free_coherent(greth->dev, 1024, greth->rx_bd_base, greth->rx_bd_base_phys);
1523 error4:
1524 	dma_free_coherent(greth->dev, 1024, greth->tx_bd_base, greth->tx_bd_base_phys);
1525 error3:
1526 	mdiobus_unregister(greth->mdio);
1527 error2:
1528 	of_iounmap(&ofdev->resource[0], greth->regs, resource_size(&ofdev->resource[0]));
1529 error1:
1530 	free_netdev(dev);
1531 	return err;
1532 }
1533 
1534 static int greth_of_remove(struct platform_device *of_dev)
1535 {
1536 	struct net_device *ndev = platform_get_drvdata(of_dev);
1537 	struct greth_private *greth = netdev_priv(ndev);
1538 
1539 	/* Free descriptor areas */
1540 	dma_free_coherent(&of_dev->dev, 1024, greth->rx_bd_base, greth->rx_bd_base_phys);
1541 
1542 	dma_free_coherent(&of_dev->dev, 1024, greth->tx_bd_base, greth->tx_bd_base_phys);
1543 
1544 	if (ndev->phydev)
1545 		phy_stop(ndev->phydev);
1546 	mdiobus_unregister(greth->mdio);
1547 
1548 	unregister_netdev(ndev);
1549 	free_netdev(ndev);
1550 
1551 	of_iounmap(&of_dev->resource[0], greth->regs, resource_size(&of_dev->resource[0]));
1552 
1553 	return 0;
1554 }
1555 
1556 static const struct of_device_id greth_of_match[] = {
1557 	{
1558 	 .name = "GAISLER_ETHMAC",
1559 	 },
1560 	{
1561 	 .name = "01_01d",
1562 	 },
1563 	{},
1564 };
1565 
1566 MODULE_DEVICE_TABLE(of, greth_of_match);
1567 
1568 static struct platform_driver greth_of_driver = {
1569 	.driver = {
1570 		.name = "grlib-greth",
1571 		.of_match_table = greth_of_match,
1572 	},
1573 	.probe = greth_of_probe,
1574 	.remove = greth_of_remove,
1575 };
1576 
1577 module_platform_driver(greth_of_driver);
1578 
1579 MODULE_AUTHOR("Aeroflex Gaisler AB.");
1580 MODULE_DESCRIPTION("Aeroflex Gaisler Ethernet MAC driver");
1581 MODULE_LICENSE("GPL");
1582