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_platform.h>
38 #include <linux/slab.h>
39 #include <asm/cacheflush.h>
40 #include <asm/byteorder.h>
41 
42 #ifdef CONFIG_SPARC
43 #include <asm/idprom.h>
44 #endif
45 
46 #include "greth.h"
47 
48 #define GRETH_DEF_MSG_ENABLE	  \
49 	(NETIF_MSG_DRV		| \
50 	 NETIF_MSG_PROBE	| \
51 	 NETIF_MSG_LINK		| \
52 	 NETIF_MSG_IFDOWN	| \
53 	 NETIF_MSG_IFUP		| \
54 	 NETIF_MSG_RX_ERR	| \
55 	 NETIF_MSG_TX_ERR)
56 
57 static int greth_debug = -1;	/* -1 == use GRETH_DEF_MSG_ENABLE as value */
58 module_param(greth_debug, int, 0);
59 MODULE_PARM_DESC(greth_debug, "GRETH bitmapped debugging message enable value");
60 
61 /* Accept MAC address of the form macaddr=0x08,0x00,0x20,0x30,0x40,0x50 */
62 static int macaddr[6];
63 module_param_array(macaddr, int, NULL, 0);
64 MODULE_PARM_DESC(macaddr, "GRETH Ethernet MAC address");
65 
66 static int greth_edcl = 1;
67 module_param(greth_edcl, int, 0);
68 MODULE_PARM_DESC(greth_edcl, "GRETH EDCL usage indicator. Set to 1 if EDCL is used.");
69 
70 static int greth_open(struct net_device *dev);
71 static netdev_tx_t greth_start_xmit(struct sk_buff *skb,
72 	   struct net_device *dev);
73 static netdev_tx_t greth_start_xmit_gbit(struct sk_buff *skb,
74 	   struct net_device *dev);
75 static int greth_rx(struct net_device *dev, int limit);
76 static int greth_rx_gbit(struct net_device *dev, int limit);
77 static void greth_clean_tx(struct net_device *dev);
78 static void greth_clean_tx_gbit(struct net_device *dev);
79 static irqreturn_t greth_interrupt(int irq, void *dev_id);
80 static int greth_close(struct net_device *dev);
81 static int greth_set_mac_add(struct net_device *dev, void *p);
82 static void greth_set_multicast_list(struct net_device *dev);
83 
84 #define GRETH_REGLOAD(a)	    (be32_to_cpu(__raw_readl(&(a))))
85 #define GRETH_REGSAVE(a, v)         (__raw_writel(cpu_to_be32(v), &(a)))
86 #define GRETH_REGORIN(a, v)         (GRETH_REGSAVE(a, (GRETH_REGLOAD(a) | (v))))
87 #define GRETH_REGANDIN(a, v)        (GRETH_REGSAVE(a, (GRETH_REGLOAD(a) & (v))))
88 
89 #define NEXT_TX(N)      (((N) + 1) & GRETH_TXBD_NUM_MASK)
90 #define SKIP_TX(N, C)   (((N) + C) & GRETH_TXBD_NUM_MASK)
91 #define NEXT_RX(N)      (((N) + 1) & GRETH_RXBD_NUM_MASK)
92 
93 static void greth_print_rx_packet(void *addr, int len)
94 {
95 	print_hex_dump(KERN_DEBUG, "RX: ", DUMP_PREFIX_OFFSET, 16, 1,
96 			addr, len, true);
97 }
98 
99 static void greth_print_tx_packet(struct sk_buff *skb)
100 {
101 	int i;
102 	int length;
103 
104 	if (skb_shinfo(skb)->nr_frags == 0)
105 		length = skb->len;
106 	else
107 		length = skb_headlen(skb);
108 
109 	print_hex_dump(KERN_DEBUG, "TX: ", DUMP_PREFIX_OFFSET, 16, 1,
110 			skb->data, length, true);
111 
112 	for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
113 
114 		print_hex_dump(KERN_DEBUG, "TX: ", DUMP_PREFIX_OFFSET, 16, 1,
115 			       skb_frag_address(&skb_shinfo(skb)->frags[i]),
116 			       skb_shinfo(skb)->frags[i].size, true);
117 	}
118 }
119 
120 static inline void greth_enable_tx(struct greth_private *greth)
121 {
122 	wmb();
123 	GRETH_REGORIN(greth->regs->control, GRETH_TXEN);
124 }
125 
126 static inline void greth_enable_tx_and_irq(struct greth_private *greth)
127 {
128 	wmb(); /* BDs must been written to memory before enabling TX */
129 	GRETH_REGORIN(greth->regs->control, GRETH_TXEN | GRETH_TXI);
130 }
131 
132 static inline void greth_disable_tx(struct greth_private *greth)
133 {
134 	GRETH_REGANDIN(greth->regs->control, ~GRETH_TXEN);
135 }
136 
137 static inline void greth_enable_rx(struct greth_private *greth)
138 {
139 	wmb();
140 	GRETH_REGORIN(greth->regs->control, GRETH_RXEN);
141 }
142 
143 static inline void greth_disable_rx(struct greth_private *greth)
144 {
145 	GRETH_REGANDIN(greth->regs->control, ~GRETH_RXEN);
146 }
147 
148 static inline void greth_enable_irqs(struct greth_private *greth)
149 {
150 	GRETH_REGORIN(greth->regs->control, GRETH_RXI | GRETH_TXI);
151 }
152 
153 static inline void greth_disable_irqs(struct greth_private *greth)
154 {
155 	GRETH_REGANDIN(greth->regs->control, ~(GRETH_RXI|GRETH_TXI));
156 }
157 
158 static inline void greth_write_bd(u32 *bd, u32 val)
159 {
160 	__raw_writel(cpu_to_be32(val), bd);
161 }
162 
163 static inline u32 greth_read_bd(u32 *bd)
164 {
165 	return be32_to_cpu(__raw_readl(bd));
166 }
167 
168 static void greth_clean_rings(struct greth_private *greth)
169 {
170 	int i;
171 	struct greth_bd *rx_bdp = greth->rx_bd_base;
172 	struct greth_bd *tx_bdp = greth->tx_bd_base;
173 
174 	if (greth->gbit_mac) {
175 
176 		/* Free and unmap RX buffers */
177 		for (i = 0; i < GRETH_RXBD_NUM; i++, rx_bdp++) {
178 			if (greth->rx_skbuff[i] != NULL) {
179 				dev_kfree_skb(greth->rx_skbuff[i]);
180 				dma_unmap_single(greth->dev,
181 						 greth_read_bd(&rx_bdp->addr),
182 						 MAX_FRAME_SIZE+NET_IP_ALIGN,
183 						 DMA_FROM_DEVICE);
184 			}
185 		}
186 
187 		/* TX buffers */
188 		while (greth->tx_free < GRETH_TXBD_NUM) {
189 
190 			struct sk_buff *skb = greth->tx_skbuff[greth->tx_last];
191 			int nr_frags = skb_shinfo(skb)->nr_frags;
192 			tx_bdp = greth->tx_bd_base + greth->tx_last;
193 			greth->tx_last = NEXT_TX(greth->tx_last);
194 
195 			dma_unmap_single(greth->dev,
196 					 greth_read_bd(&tx_bdp->addr),
197 					 skb_headlen(skb),
198 					 DMA_TO_DEVICE);
199 
200 			for (i = 0; i < nr_frags; i++) {
201 				skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
202 				tx_bdp = greth->tx_bd_base + greth->tx_last;
203 
204 				dma_unmap_page(greth->dev,
205 					       greth_read_bd(&tx_bdp->addr),
206 					       skb_frag_size(frag),
207 					       DMA_TO_DEVICE);
208 
209 				greth->tx_last = NEXT_TX(greth->tx_last);
210 			}
211 			greth->tx_free += nr_frags+1;
212 			dev_kfree_skb(skb);
213 		}
214 
215 
216 	} else { /* 10/100 Mbps MAC */
217 
218 		for (i = 0; i < GRETH_RXBD_NUM; i++, rx_bdp++) {
219 			kfree(greth->rx_bufs[i]);
220 			dma_unmap_single(greth->dev,
221 					 greth_read_bd(&rx_bdp->addr),
222 					 MAX_FRAME_SIZE,
223 					 DMA_FROM_DEVICE);
224 		}
225 		for (i = 0; i < GRETH_TXBD_NUM; i++, tx_bdp++) {
226 			kfree(greth->tx_bufs[i]);
227 			dma_unmap_single(greth->dev,
228 					 greth_read_bd(&tx_bdp->addr),
229 					 MAX_FRAME_SIZE,
230 					 DMA_TO_DEVICE);
231 		}
232 	}
233 }
234 
235 static int greth_init_rings(struct greth_private *greth)
236 {
237 	struct sk_buff *skb;
238 	struct greth_bd *rx_bd, *tx_bd;
239 	u32 dma_addr;
240 	int i;
241 
242 	rx_bd = greth->rx_bd_base;
243 	tx_bd = greth->tx_bd_base;
244 
245 	/* Initialize descriptor rings and buffers */
246 	if (greth->gbit_mac) {
247 
248 		for (i = 0; i < GRETH_RXBD_NUM; i++) {
249 			skb = netdev_alloc_skb(greth->netdev, MAX_FRAME_SIZE+NET_IP_ALIGN);
250 			if (skb == NULL) {
251 				if (netif_msg_ifup(greth))
252 					dev_err(greth->dev, "Error allocating DMA ring.\n");
253 				goto cleanup;
254 			}
255 			skb_reserve(skb, NET_IP_ALIGN);
256 			dma_addr = dma_map_single(greth->dev,
257 						  skb->data,
258 						  MAX_FRAME_SIZE+NET_IP_ALIGN,
259 						  DMA_FROM_DEVICE);
260 
261 			if (dma_mapping_error(greth->dev, dma_addr)) {
262 				if (netif_msg_ifup(greth))
263 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
264 				goto cleanup;
265 			}
266 			greth->rx_skbuff[i] = skb;
267 			greth_write_bd(&rx_bd[i].addr, dma_addr);
268 			greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
269 		}
270 
271 	} else {
272 
273 		/* 10/100 MAC uses a fixed set of buffers and copy to/from SKBs */
274 		for (i = 0; i < GRETH_RXBD_NUM; i++) {
275 
276 			greth->rx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);
277 
278 			if (greth->rx_bufs[i] == NULL) {
279 				if (netif_msg_ifup(greth))
280 					dev_err(greth->dev, "Error allocating DMA ring.\n");
281 				goto cleanup;
282 			}
283 
284 			dma_addr = dma_map_single(greth->dev,
285 						  greth->rx_bufs[i],
286 						  MAX_FRAME_SIZE,
287 						  DMA_FROM_DEVICE);
288 
289 			if (dma_mapping_error(greth->dev, dma_addr)) {
290 				if (netif_msg_ifup(greth))
291 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
292 				goto cleanup;
293 			}
294 			greth_write_bd(&rx_bd[i].addr, dma_addr);
295 			greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
296 		}
297 		for (i = 0; i < GRETH_TXBD_NUM; i++) {
298 
299 			greth->tx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);
300 
301 			if (greth->tx_bufs[i] == NULL) {
302 				if (netif_msg_ifup(greth))
303 					dev_err(greth->dev, "Error allocating DMA ring.\n");
304 				goto cleanup;
305 			}
306 
307 			dma_addr = dma_map_single(greth->dev,
308 						  greth->tx_bufs[i],
309 						  MAX_FRAME_SIZE,
310 						  DMA_TO_DEVICE);
311 
312 			if (dma_mapping_error(greth->dev, dma_addr)) {
313 				if (netif_msg_ifup(greth))
314 					dev_err(greth->dev, "Could not create initial DMA mapping\n");
315 				goto cleanup;
316 			}
317 			greth_write_bd(&tx_bd[i].addr, dma_addr);
318 			greth_write_bd(&tx_bd[i].stat, 0);
319 		}
320 	}
321 	greth_write_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat,
322 		       greth_read_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat) | GRETH_BD_WR);
323 
324 	/* Initialize pointers. */
325 	greth->rx_cur = 0;
326 	greth->tx_next = 0;
327 	greth->tx_last = 0;
328 	greth->tx_free = GRETH_TXBD_NUM;
329 
330 	/* Initialize descriptor base address */
331 	GRETH_REGSAVE(greth->regs->tx_desc_p, greth->tx_bd_base_phys);
332 	GRETH_REGSAVE(greth->regs->rx_desc_p, greth->rx_bd_base_phys);
333 
334 	return 0;
335 
336 cleanup:
337 	greth_clean_rings(greth);
338 	return -ENOMEM;
339 }
340 
341 static int greth_open(struct net_device *dev)
342 {
343 	struct greth_private *greth = netdev_priv(dev);
344 	int err;
345 
346 	err = greth_init_rings(greth);
347 	if (err) {
348 		if (netif_msg_ifup(greth))
349 			dev_err(&dev->dev, "Could not allocate memory for DMA rings\n");
350 		return err;
351 	}
352 
353 	err = request_irq(greth->irq, greth_interrupt, 0, "eth", (void *) dev);
354 	if (err) {
355 		if (netif_msg_ifup(greth))
356 			dev_err(&dev->dev, "Could not allocate interrupt %d\n", dev->irq);
357 		greth_clean_rings(greth);
358 		return err;
359 	}
360 
361 	if (netif_msg_ifup(greth))
362 		dev_dbg(&dev->dev, " starting queue\n");
363 	netif_start_queue(dev);
364 
365 	GRETH_REGSAVE(greth->regs->status, 0xFF);
366 
367 	napi_enable(&greth->napi);
368 
369 	greth_enable_irqs(greth);
370 	greth_enable_tx(greth);
371 	greth_enable_rx(greth);
372 	return 0;
373 
374 }
375 
376 static int greth_close(struct net_device *dev)
377 {
378 	struct greth_private *greth = netdev_priv(dev);
379 
380 	napi_disable(&greth->napi);
381 
382 	greth_disable_irqs(greth);
383 	greth_disable_tx(greth);
384 	greth_disable_rx(greth);
385 
386 	netif_stop_queue(dev);
387 
388 	free_irq(greth->irq, (void *) dev);
389 
390 	greth_clean_rings(greth);
391 
392 	return 0;
393 }
394 
395 static netdev_tx_t
396 greth_start_xmit(struct sk_buff *skb, struct net_device *dev)
397 {
398 	struct greth_private *greth = netdev_priv(dev);
399 	struct greth_bd *bdp;
400 	int err = NETDEV_TX_OK;
401 	u32 status, dma_addr, ctrl;
402 	unsigned long flags;
403 
404 	/* Clean TX Ring */
405 	greth_clean_tx(greth->netdev);
406 
407 	if (unlikely(greth->tx_free <= 0)) {
408 		spin_lock_irqsave(&greth->devlock, flags);/*save from poll/irq*/
409 		ctrl = GRETH_REGLOAD(greth->regs->control);
410 		/* Enable TX IRQ only if not already in poll() routine */
411 		if (ctrl & GRETH_RXI)
412 			GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_TXI);
413 		netif_stop_queue(dev);
414 		spin_unlock_irqrestore(&greth->devlock, flags);
415 		return NETDEV_TX_BUSY;
416 	}
417 
418 	if (netif_msg_pktdata(greth))
419 		greth_print_tx_packet(skb);
420 
421 
422 	if (unlikely(skb->len > MAX_FRAME_SIZE)) {
423 		dev->stats.tx_errors++;
424 		goto out;
425 	}
426 
427 	bdp = greth->tx_bd_base + greth->tx_next;
428 	dma_addr = greth_read_bd(&bdp->addr);
429 
430 	memcpy((unsigned char *) phys_to_virt(dma_addr), skb->data, skb->len);
431 
432 	dma_sync_single_for_device(greth->dev, dma_addr, skb->len, DMA_TO_DEVICE);
433 
434 	status = GRETH_BD_EN | GRETH_BD_IE | (skb->len & GRETH_BD_LEN);
435 	greth->tx_bufs_length[greth->tx_next] = skb->len & GRETH_BD_LEN;
436 
437 	/* Wrap around descriptor ring */
438 	if (greth->tx_next == GRETH_TXBD_NUM_MASK) {
439 		status |= GRETH_BD_WR;
440 	}
441 
442 	greth->tx_next = NEXT_TX(greth->tx_next);
443 	greth->tx_free--;
444 
445 	/* Write descriptor control word and enable transmission */
446 	greth_write_bd(&bdp->stat, status);
447 	spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
448 	greth_enable_tx(greth);
449 	spin_unlock_irqrestore(&greth->devlock, flags);
450 
451 out:
452 	dev_kfree_skb(skb);
453 	return err;
454 }
455 
456 static inline u16 greth_num_free_bds(u16 tx_last, u16 tx_next)
457 {
458 	if (tx_next < tx_last)
459 		return (tx_last - tx_next) - 1;
460 	else
461 		return GRETH_TXBD_NUM - (tx_next - tx_last) - 1;
462 }
463 
464 static netdev_tx_t
465 greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
466 {
467 	struct greth_private *greth = netdev_priv(dev);
468 	struct greth_bd *bdp;
469 	u32 status, dma_addr;
470 	int curr_tx, nr_frags, i, err = NETDEV_TX_OK;
471 	unsigned long flags;
472 	u16 tx_last;
473 
474 	nr_frags = skb_shinfo(skb)->nr_frags;
475 	tx_last = greth->tx_last;
476 	rmb(); /* tx_last is updated by the poll task */
477 
478 	if (greth_num_free_bds(tx_last, greth->tx_next) < nr_frags + 1) {
479 		netif_stop_queue(dev);
480 		err = NETDEV_TX_BUSY;
481 		goto out;
482 	}
483 
484 	if (netif_msg_pktdata(greth))
485 		greth_print_tx_packet(skb);
486 
487 	if (unlikely(skb->len > MAX_FRAME_SIZE)) {
488 		dev->stats.tx_errors++;
489 		goto out;
490 	}
491 
492 	/* Save skb pointer. */
493 	greth->tx_skbuff[greth->tx_next] = skb;
494 
495 	/* Linear buf */
496 	if (nr_frags != 0)
497 		status = GRETH_TXBD_MORE;
498 	else
499 		status = GRETH_BD_IE;
500 
501 	if (skb->ip_summed == CHECKSUM_PARTIAL)
502 		status |= GRETH_TXBD_CSALL;
503 	status |= skb_headlen(skb) & GRETH_BD_LEN;
504 	if (greth->tx_next == GRETH_TXBD_NUM_MASK)
505 		status |= GRETH_BD_WR;
506 
507 
508 	bdp = greth->tx_bd_base + greth->tx_next;
509 	greth_write_bd(&bdp->stat, status);
510 	dma_addr = dma_map_single(greth->dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
511 
512 	if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
513 		goto map_error;
514 
515 	greth_write_bd(&bdp->addr, dma_addr);
516 
517 	curr_tx = NEXT_TX(greth->tx_next);
518 
519 	/* Frags */
520 	for (i = 0; i < nr_frags; i++) {
521 		skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
522 		greth->tx_skbuff[curr_tx] = NULL;
523 		bdp = greth->tx_bd_base + curr_tx;
524 
525 		status = GRETH_BD_EN;
526 		if (skb->ip_summed == CHECKSUM_PARTIAL)
527 			status |= GRETH_TXBD_CSALL;
528 		status |= skb_frag_size(frag) & GRETH_BD_LEN;
529 
530 		/* Wrap around descriptor ring */
531 		if (curr_tx == GRETH_TXBD_NUM_MASK)
532 			status |= GRETH_BD_WR;
533 
534 		/* More fragments left */
535 		if (i < nr_frags - 1)
536 			status |= GRETH_TXBD_MORE;
537 		else
538 			status |= GRETH_BD_IE; /* enable IRQ on last fragment */
539 
540 		greth_write_bd(&bdp->stat, status);
541 
542 		dma_addr = skb_frag_dma_map(greth->dev, frag, 0, skb_frag_size(frag),
543 					    DMA_TO_DEVICE);
544 
545 		if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
546 			goto frag_map_error;
547 
548 		greth_write_bd(&bdp->addr, dma_addr);
549 
550 		curr_tx = NEXT_TX(curr_tx);
551 	}
552 
553 	wmb();
554 
555 	/* Enable the descriptor chain by enabling the first descriptor */
556 	bdp = greth->tx_bd_base + greth->tx_next;
557 	greth_write_bd(&bdp->stat,
558 		       greth_read_bd(&bdp->stat) | GRETH_BD_EN);
559 
560 	spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
561 	greth->tx_next = curr_tx;
562 	greth_enable_tx_and_irq(greth);
563 	spin_unlock_irqrestore(&greth->devlock, flags);
564 
565 	return NETDEV_TX_OK;
566 
567 frag_map_error:
568 	/* Unmap SKB mappings that succeeded and disable descriptor */
569 	for (i = 0; greth->tx_next + i != curr_tx; i++) {
570 		bdp = greth->tx_bd_base + greth->tx_next + i;
571 		dma_unmap_single(greth->dev,
572 				 greth_read_bd(&bdp->addr),
573 				 greth_read_bd(&bdp->stat) & GRETH_BD_LEN,
574 				 DMA_TO_DEVICE);
575 		greth_write_bd(&bdp->stat, 0);
576 	}
577 map_error:
578 	if (net_ratelimit())
579 		dev_warn(greth->dev, "Could not create TX DMA mapping\n");
580 	dev_kfree_skb(skb);
581 out:
582 	return err;
583 }
584 
585 static irqreturn_t greth_interrupt(int irq, void *dev_id)
586 {
587 	struct net_device *dev = dev_id;
588 	struct greth_private *greth;
589 	u32 status, ctrl;
590 	irqreturn_t retval = IRQ_NONE;
591 
592 	greth = netdev_priv(dev);
593 
594 	spin_lock(&greth->devlock);
595 
596 	/* Get the interrupt events that caused us to be here. */
597 	status = GRETH_REGLOAD(greth->regs->status);
598 
599 	/* Must see if interrupts are enabled also, INT_TX|INT_RX flags may be
600 	 * set regardless of whether IRQ is enabled or not. Especially
601 	 * important when shared IRQ.
602 	 */
603 	ctrl = GRETH_REGLOAD(greth->regs->control);
604 
605 	/* Handle rx and tx interrupts through poll */
606 	if (((status & (GRETH_INT_RE | GRETH_INT_RX)) && (ctrl & GRETH_RXI)) ||
607 	    ((status & (GRETH_INT_TE | GRETH_INT_TX)) && (ctrl & GRETH_TXI))) {
608 		retval = IRQ_HANDLED;
609 
610 		/* Disable interrupts and schedule poll() */
611 		greth_disable_irqs(greth);
612 		napi_schedule(&greth->napi);
613 	}
614 
615 	mmiowb();
616 	spin_unlock(&greth->devlock);
617 
618 	return retval;
619 }
620 
621 static void greth_clean_tx(struct net_device *dev)
622 {
623 	struct greth_private *greth;
624 	struct greth_bd *bdp;
625 	u32 stat;
626 
627 	greth = netdev_priv(dev);
628 
629 	while (1) {
630 		bdp = greth->tx_bd_base + greth->tx_last;
631 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
632 		mb();
633 		stat = greth_read_bd(&bdp->stat);
634 
635 		if (unlikely(stat & GRETH_BD_EN))
636 			break;
637 
638 		if (greth->tx_free == GRETH_TXBD_NUM)
639 			break;
640 
641 		/* Check status for errors */
642 		if (unlikely(stat & GRETH_TXBD_STATUS)) {
643 			dev->stats.tx_errors++;
644 			if (stat & GRETH_TXBD_ERR_AL)
645 				dev->stats.tx_aborted_errors++;
646 			if (stat & GRETH_TXBD_ERR_UE)
647 				dev->stats.tx_fifo_errors++;
648 		}
649 		dev->stats.tx_packets++;
650 		dev->stats.tx_bytes += greth->tx_bufs_length[greth->tx_last];
651 		greth->tx_last = NEXT_TX(greth->tx_last);
652 		greth->tx_free++;
653 	}
654 
655 	if (greth->tx_free > 0) {
656 		netif_wake_queue(dev);
657 	}
658 }
659 
660 static inline void greth_update_tx_stats(struct net_device *dev, u32 stat)
661 {
662 	/* Check status for errors */
663 	if (unlikely(stat & GRETH_TXBD_STATUS)) {
664 		dev->stats.tx_errors++;
665 		if (stat & GRETH_TXBD_ERR_AL)
666 			dev->stats.tx_aborted_errors++;
667 		if (stat & GRETH_TXBD_ERR_UE)
668 			dev->stats.tx_fifo_errors++;
669 		if (stat & GRETH_TXBD_ERR_LC)
670 			dev->stats.tx_aborted_errors++;
671 	}
672 	dev->stats.tx_packets++;
673 }
674 
675 static void greth_clean_tx_gbit(struct net_device *dev)
676 {
677 	struct greth_private *greth;
678 	struct greth_bd *bdp, *bdp_last_frag;
679 	struct sk_buff *skb = NULL;
680 	u32 stat;
681 	int nr_frags, i;
682 	u16 tx_last;
683 
684 	greth = netdev_priv(dev);
685 	tx_last = greth->tx_last;
686 
687 	while (tx_last != greth->tx_next) {
688 
689 		skb = greth->tx_skbuff[tx_last];
690 
691 		nr_frags = skb_shinfo(skb)->nr_frags;
692 
693 		/* We only clean fully completed SKBs */
694 		bdp_last_frag = greth->tx_bd_base + SKIP_TX(tx_last, nr_frags);
695 
696 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
697 		mb();
698 		stat = greth_read_bd(&bdp_last_frag->stat);
699 
700 		if (stat & GRETH_BD_EN)
701 			break;
702 
703 		greth->tx_skbuff[tx_last] = NULL;
704 
705 		greth_update_tx_stats(dev, stat);
706 		dev->stats.tx_bytes += skb->len;
707 
708 		bdp = greth->tx_bd_base + tx_last;
709 
710 		tx_last = NEXT_TX(tx_last);
711 
712 		dma_unmap_single(greth->dev,
713 				 greth_read_bd(&bdp->addr),
714 				 skb_headlen(skb),
715 				 DMA_TO_DEVICE);
716 
717 		for (i = 0; i < nr_frags; i++) {
718 			skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
719 			bdp = greth->tx_bd_base + tx_last;
720 
721 			dma_unmap_page(greth->dev,
722 				       greth_read_bd(&bdp->addr),
723 				       skb_frag_size(frag),
724 				       DMA_TO_DEVICE);
725 
726 			tx_last = NEXT_TX(tx_last);
727 		}
728 		dev_kfree_skb(skb);
729 	}
730 	if (skb) { /* skb is set only if the above while loop was entered */
731 		wmb();
732 		greth->tx_last = tx_last;
733 
734 		if (netif_queue_stopped(dev) &&
735 		    (greth_num_free_bds(tx_last, greth->tx_next) >
736 		    (MAX_SKB_FRAGS+1)))
737 			netif_wake_queue(dev);
738 	}
739 }
740 
741 static int greth_rx(struct net_device *dev, int limit)
742 {
743 	struct greth_private *greth;
744 	struct greth_bd *bdp;
745 	struct sk_buff *skb;
746 	int pkt_len;
747 	int bad, count;
748 	u32 status, dma_addr;
749 	unsigned long flags;
750 
751 	greth = netdev_priv(dev);
752 
753 	for (count = 0; count < limit; ++count) {
754 
755 		bdp = greth->rx_bd_base + greth->rx_cur;
756 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
757 		mb();
758 		status = greth_read_bd(&bdp->stat);
759 
760 		if (unlikely(status & GRETH_BD_EN)) {
761 			break;
762 		}
763 
764 		dma_addr = greth_read_bd(&bdp->addr);
765 		bad = 0;
766 
767 		/* Check status for errors. */
768 		if (unlikely(status & GRETH_RXBD_STATUS)) {
769 			if (status & GRETH_RXBD_ERR_FT) {
770 				dev->stats.rx_length_errors++;
771 				bad = 1;
772 			}
773 			if (status & (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE)) {
774 				dev->stats.rx_frame_errors++;
775 				bad = 1;
776 			}
777 			if (status & GRETH_RXBD_ERR_CRC) {
778 				dev->stats.rx_crc_errors++;
779 				bad = 1;
780 			}
781 		}
782 		if (unlikely(bad)) {
783 			dev->stats.rx_errors++;
784 
785 		} else {
786 
787 			pkt_len = status & GRETH_BD_LEN;
788 
789 			skb = netdev_alloc_skb(dev, pkt_len + NET_IP_ALIGN);
790 
791 			if (unlikely(skb == NULL)) {
792 
793 				if (net_ratelimit())
794 					dev_warn(&dev->dev, "low on memory - " "packet dropped\n");
795 
796 				dev->stats.rx_dropped++;
797 
798 			} else {
799 				skb_reserve(skb, NET_IP_ALIGN);
800 
801 				dma_sync_single_for_cpu(greth->dev,
802 							dma_addr,
803 							pkt_len,
804 							DMA_FROM_DEVICE);
805 
806 				if (netif_msg_pktdata(greth))
807 					greth_print_rx_packet(phys_to_virt(dma_addr), pkt_len);
808 
809 				memcpy(skb_put(skb, pkt_len), phys_to_virt(dma_addr), pkt_len);
810 
811 				skb->protocol = eth_type_trans(skb, dev);
812 				dev->stats.rx_bytes += pkt_len;
813 				dev->stats.rx_packets++;
814 				netif_receive_skb(skb);
815 			}
816 		}
817 
818 		status = GRETH_BD_EN | GRETH_BD_IE;
819 		if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
820 			status |= GRETH_BD_WR;
821 		}
822 
823 		wmb();
824 		greth_write_bd(&bdp->stat, status);
825 
826 		dma_sync_single_for_device(greth->dev, dma_addr, MAX_FRAME_SIZE, DMA_FROM_DEVICE);
827 
828 		spin_lock_irqsave(&greth->devlock, flags); /* save from XMIT */
829 		greth_enable_rx(greth);
830 		spin_unlock_irqrestore(&greth->devlock, flags);
831 
832 		greth->rx_cur = NEXT_RX(greth->rx_cur);
833 	}
834 
835 	return count;
836 }
837 
838 static inline int hw_checksummed(u32 status)
839 {
840 
841 	if (status & GRETH_RXBD_IP_FRAG)
842 		return 0;
843 
844 	if (status & GRETH_RXBD_IP && status & GRETH_RXBD_IP_CSERR)
845 		return 0;
846 
847 	if (status & GRETH_RXBD_UDP && status & GRETH_RXBD_UDP_CSERR)
848 		return 0;
849 
850 	if (status & GRETH_RXBD_TCP && status & GRETH_RXBD_TCP_CSERR)
851 		return 0;
852 
853 	return 1;
854 }
855 
856 static int greth_rx_gbit(struct net_device *dev, int limit)
857 {
858 	struct greth_private *greth;
859 	struct greth_bd *bdp;
860 	struct sk_buff *skb, *newskb;
861 	int pkt_len;
862 	int bad, count = 0;
863 	u32 status, dma_addr;
864 	unsigned long flags;
865 
866 	greth = netdev_priv(dev);
867 
868 	for (count = 0; count < limit; ++count) {
869 
870 		bdp = greth->rx_bd_base + greth->rx_cur;
871 		skb = greth->rx_skbuff[greth->rx_cur];
872 		GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
873 		mb();
874 		status = greth_read_bd(&bdp->stat);
875 		bad = 0;
876 
877 		if (status & GRETH_BD_EN)
878 			break;
879 
880 		/* Check status for errors. */
881 		if (unlikely(status & GRETH_RXBD_STATUS)) {
882 
883 			if (status & GRETH_RXBD_ERR_FT) {
884 				dev->stats.rx_length_errors++;
885 				bad = 1;
886 			} else if (status &
887 				   (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE | GRETH_RXBD_ERR_LE)) {
888 				dev->stats.rx_frame_errors++;
889 				bad = 1;
890 			} else if (status & GRETH_RXBD_ERR_CRC) {
891 				dev->stats.rx_crc_errors++;
892 				bad = 1;
893 			}
894 		}
895 
896 		/* Allocate new skb to replace current, not needed if the
897 		 * current skb can be reused */
898 		if (!bad && (newskb=netdev_alloc_skb(dev, MAX_FRAME_SIZE + NET_IP_ALIGN))) {
899 			skb_reserve(newskb, NET_IP_ALIGN);
900 
901 			dma_addr = dma_map_single(greth->dev,
902 						      newskb->data,
903 						      MAX_FRAME_SIZE + NET_IP_ALIGN,
904 						      DMA_FROM_DEVICE);
905 
906 			if (!dma_mapping_error(greth->dev, dma_addr)) {
907 				/* Process the incoming frame. */
908 				pkt_len = status & GRETH_BD_LEN;
909 
910 				dma_unmap_single(greth->dev,
911 						 greth_read_bd(&bdp->addr),
912 						 MAX_FRAME_SIZE + NET_IP_ALIGN,
913 						 DMA_FROM_DEVICE);
914 
915 				if (netif_msg_pktdata(greth))
916 					greth_print_rx_packet(phys_to_virt(greth_read_bd(&bdp->addr)), pkt_len);
917 
918 				skb_put(skb, pkt_len);
919 
920 				if (dev->features & NETIF_F_RXCSUM && hw_checksummed(status))
921 					skb->ip_summed = CHECKSUM_UNNECESSARY;
922 				else
923 					skb_checksum_none_assert(skb);
924 
925 				skb->protocol = eth_type_trans(skb, dev);
926 				dev->stats.rx_packets++;
927 				dev->stats.rx_bytes += pkt_len;
928 				netif_receive_skb(skb);
929 
930 				greth->rx_skbuff[greth->rx_cur] = newskb;
931 				greth_write_bd(&bdp->addr, dma_addr);
932 			} else {
933 				if (net_ratelimit())
934 					dev_warn(greth->dev, "Could not create DMA mapping, dropping packet\n");
935 				dev_kfree_skb(newskb);
936 				/* reusing current skb, so it is a drop */
937 				dev->stats.rx_dropped++;
938 			}
939 		} else if (bad) {
940 			/* Bad Frame transfer, the skb is reused */
941 			dev->stats.rx_dropped++;
942 		} else {
943 			/* Failed Allocating a new skb. This is rather stupid
944 			 * but the current "filled" skb is reused, as if
945 			 * transfer failure. One could argue that RX descriptor
946 			 * table handling should be divided into cleaning and
947 			 * filling as the TX part of the driver
948 			 */
949 			if (net_ratelimit())
950 				dev_warn(greth->dev, "Could not allocate SKB, dropping packet\n");
951 			/* reusing current skb, so it is a drop */
952 			dev->stats.rx_dropped++;
953 		}
954 
955 		status = GRETH_BD_EN | GRETH_BD_IE;
956 		if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
957 			status |= GRETH_BD_WR;
958 		}
959 
960 		wmb();
961 		greth_write_bd(&bdp->stat, status);
962 		spin_lock_irqsave(&greth->devlock, flags);
963 		greth_enable_rx(greth);
964 		spin_unlock_irqrestore(&greth->devlock, flags);
965 		greth->rx_cur = NEXT_RX(greth->rx_cur);
966 	}
967 
968 	return count;
969 
970 }
971 
972 static int greth_poll(struct napi_struct *napi, int budget)
973 {
974 	struct greth_private *greth;
975 	int work_done = 0;
976 	unsigned long flags;
977 	u32 mask, ctrl;
978 	greth = container_of(napi, struct greth_private, napi);
979 
980 restart_txrx_poll:
981 	if (greth->gbit_mac) {
982 		greth_clean_tx_gbit(greth->netdev);
983 		work_done += greth_rx_gbit(greth->netdev, budget - work_done);
984 	} else {
985 		if (netif_queue_stopped(greth->netdev))
986 			greth_clean_tx(greth->netdev);
987 		work_done += greth_rx(greth->netdev, budget - work_done);
988 	}
989 
990 	if (work_done < budget) {
991 
992 		spin_lock_irqsave(&greth->devlock, flags);
993 
994 		ctrl = GRETH_REGLOAD(greth->regs->control);
995 		if ((greth->gbit_mac && (greth->tx_last != greth->tx_next)) ||
996 		    (!greth->gbit_mac && netif_queue_stopped(greth->netdev))) {
997 			GRETH_REGSAVE(greth->regs->control,
998 					ctrl | GRETH_TXI | GRETH_RXI);
999 			mask = GRETH_INT_RX | GRETH_INT_RE |
1000 			       GRETH_INT_TX | GRETH_INT_TE;
1001 		} else {
1002 			GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_RXI);
1003 			mask = GRETH_INT_RX | GRETH_INT_RE;
1004 		}
1005 
1006 		if (GRETH_REGLOAD(greth->regs->status) & mask) {
1007 			GRETH_REGSAVE(greth->regs->control, ctrl);
1008 			spin_unlock_irqrestore(&greth->devlock, flags);
1009 			goto restart_txrx_poll;
1010 		} else {
1011 			__napi_complete(napi);
1012 			spin_unlock_irqrestore(&greth->devlock, flags);
1013 		}
1014 	}
1015 
1016 	return work_done;
1017 }
1018 
1019 static int greth_set_mac_add(struct net_device *dev, void *p)
1020 {
1021 	struct sockaddr *addr = p;
1022 	struct greth_private *greth;
1023 	struct greth_regs *regs;
1024 
1025 	greth = netdev_priv(dev);
1026 	regs = greth->regs;
1027 
1028 	if (!is_valid_ether_addr(addr->sa_data))
1029 		return -EADDRNOTAVAIL;
1030 
1031 	memcpy(dev->dev_addr, addr->sa_data, dev->addr_len);
1032 	GRETH_REGSAVE(regs->esa_msb, dev->dev_addr[0] << 8 | dev->dev_addr[1]);
1033 	GRETH_REGSAVE(regs->esa_lsb, dev->dev_addr[2] << 24 | dev->dev_addr[3] << 16 |
1034 		      dev->dev_addr[4] << 8 | dev->dev_addr[5]);
1035 
1036 	return 0;
1037 }
1038 
1039 static u32 greth_hash_get_index(__u8 *addr)
1040 {
1041 	return (ether_crc(6, addr)) & 0x3F;
1042 }
1043 
1044 static void greth_set_hash_filter(struct net_device *dev)
1045 {
1046 	struct netdev_hw_addr *ha;
1047 	struct greth_private *greth = netdev_priv(dev);
1048 	struct greth_regs *regs = greth->regs;
1049 	u32 mc_filter[2];
1050 	unsigned int bitnr;
1051 
1052 	mc_filter[0] = mc_filter[1] = 0;
1053 
1054 	netdev_for_each_mc_addr(ha, dev) {
1055 		bitnr = greth_hash_get_index(ha->addr);
1056 		mc_filter[bitnr >> 5] |= 1 << (bitnr & 31);
1057 	}
1058 
1059 	GRETH_REGSAVE(regs->hash_msb, mc_filter[1]);
1060 	GRETH_REGSAVE(regs->hash_lsb, mc_filter[0]);
1061 }
1062 
1063 static void greth_set_multicast_list(struct net_device *dev)
1064 {
1065 	int cfg;
1066 	struct greth_private *greth = netdev_priv(dev);
1067 	struct greth_regs *regs = greth->regs;
1068 
1069 	cfg = GRETH_REGLOAD(regs->control);
1070 	if (dev->flags & IFF_PROMISC)
1071 		cfg |= GRETH_CTRL_PR;
1072 	else
1073 		cfg &= ~GRETH_CTRL_PR;
1074 
1075 	if (greth->multicast) {
1076 		if (dev->flags & IFF_ALLMULTI) {
1077 			GRETH_REGSAVE(regs->hash_msb, -1);
1078 			GRETH_REGSAVE(regs->hash_lsb, -1);
1079 			cfg |= GRETH_CTRL_MCEN;
1080 			GRETH_REGSAVE(regs->control, cfg);
1081 			return;
1082 		}
1083 
1084 		if (netdev_mc_empty(dev)) {
1085 			cfg &= ~GRETH_CTRL_MCEN;
1086 			GRETH_REGSAVE(regs->control, cfg);
1087 			return;
1088 		}
1089 
1090 		/* Setup multicast filter */
1091 		greth_set_hash_filter(dev);
1092 		cfg |= GRETH_CTRL_MCEN;
1093 	}
1094 	GRETH_REGSAVE(regs->control, cfg);
1095 }
1096 
1097 static u32 greth_get_msglevel(struct net_device *dev)
1098 {
1099 	struct greth_private *greth = netdev_priv(dev);
1100 	return greth->msg_enable;
1101 }
1102 
1103 static void greth_set_msglevel(struct net_device *dev, u32 value)
1104 {
1105 	struct greth_private *greth = netdev_priv(dev);
1106 	greth->msg_enable = value;
1107 }
1108 static int greth_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1109 {
1110 	struct greth_private *greth = netdev_priv(dev);
1111 	struct phy_device *phy = greth->phy;
1112 
1113 	if (!phy)
1114 		return -ENODEV;
1115 
1116 	return phy_ethtool_gset(phy, cmd);
1117 }
1118 
1119 static int greth_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
1120 {
1121 	struct greth_private *greth = netdev_priv(dev);
1122 	struct phy_device *phy = greth->phy;
1123 
1124 	if (!phy)
1125 		return -ENODEV;
1126 
1127 	return phy_ethtool_sset(phy, cmd);
1128 }
1129 
1130 static int greth_get_regs_len(struct net_device *dev)
1131 {
1132 	return sizeof(struct greth_regs);
1133 }
1134 
1135 static void greth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
1136 {
1137 	struct greth_private *greth = netdev_priv(dev);
1138 
1139 	strlcpy(info->driver, dev_driver_string(greth->dev),
1140 		sizeof(info->driver));
1141 	strlcpy(info->version, "revision: 1.0", sizeof(info->version));
1142 	strlcpy(info->bus_info, greth->dev->bus->name, sizeof(info->bus_info));
1143 	strlcpy(info->fw_version, "N/A", sizeof(info->fw_version));
1144 }
1145 
1146 static void greth_get_regs(struct net_device *dev, struct ethtool_regs *regs, void *p)
1147 {
1148 	int i;
1149 	struct greth_private *greth = netdev_priv(dev);
1150 	u32 __iomem *greth_regs = (u32 __iomem *) greth->regs;
1151 	u32 *buff = p;
1152 
1153 	for (i = 0; i < sizeof(struct greth_regs) / sizeof(u32); i++)
1154 		buff[i] = greth_read_bd(&greth_regs[i]);
1155 }
1156 
1157 static const struct ethtool_ops greth_ethtool_ops = {
1158 	.get_msglevel		= greth_get_msglevel,
1159 	.set_msglevel		= greth_set_msglevel,
1160 	.get_settings		= greth_get_settings,
1161 	.set_settings		= greth_set_settings,
1162 	.get_drvinfo		= greth_get_drvinfo,
1163 	.get_regs_len           = greth_get_regs_len,
1164 	.get_regs               = greth_get_regs,
1165 	.get_link		= ethtool_op_get_link,
1166 };
1167 
1168 static struct net_device_ops greth_netdev_ops = {
1169 	.ndo_open		= greth_open,
1170 	.ndo_stop		= greth_close,
1171 	.ndo_start_xmit		= greth_start_xmit,
1172 	.ndo_set_mac_address	= greth_set_mac_add,
1173 	.ndo_validate_addr	= eth_validate_addr,
1174 };
1175 
1176 static inline int wait_for_mdio(struct greth_private *greth)
1177 {
1178 	unsigned long timeout = jiffies + 4*HZ/100;
1179 	while (GRETH_REGLOAD(greth->regs->mdio) & GRETH_MII_BUSY) {
1180 		if (time_after(jiffies, timeout))
1181 			return 0;
1182 	}
1183 	return 1;
1184 }
1185 
1186 static int greth_mdio_read(struct mii_bus *bus, int phy, int reg)
1187 {
1188 	struct greth_private *greth = bus->priv;
1189 	int data;
1190 
1191 	if (!wait_for_mdio(greth))
1192 		return -EBUSY;
1193 
1194 	GRETH_REGSAVE(greth->regs->mdio, ((phy & 0x1F) << 11) | ((reg & 0x1F) << 6) | 2);
1195 
1196 	if (!wait_for_mdio(greth))
1197 		return -EBUSY;
1198 
1199 	if (!(GRETH_REGLOAD(greth->regs->mdio) & GRETH_MII_NVALID)) {
1200 		data = (GRETH_REGLOAD(greth->regs->mdio) >> 16) & 0xFFFF;
1201 		return data;
1202 
1203 	} else {
1204 		return -1;
1205 	}
1206 }
1207 
1208 static int greth_mdio_write(struct mii_bus *bus, int phy, int reg, u16 val)
1209 {
1210 	struct greth_private *greth = bus->priv;
1211 
1212 	if (!wait_for_mdio(greth))
1213 		return -EBUSY;
1214 
1215 	GRETH_REGSAVE(greth->regs->mdio,
1216 		      ((val & 0xFFFF) << 16) | ((phy & 0x1F) << 11) | ((reg & 0x1F) << 6) | 1);
1217 
1218 	if (!wait_for_mdio(greth))
1219 		return -EBUSY;
1220 
1221 	return 0;
1222 }
1223 
1224 static void greth_link_change(struct net_device *dev)
1225 {
1226 	struct greth_private *greth = netdev_priv(dev);
1227 	struct phy_device *phydev = greth->phy;
1228 	unsigned long flags;
1229 	int status_change = 0;
1230 	u32 ctrl;
1231 
1232 	spin_lock_irqsave(&greth->devlock, flags);
1233 
1234 	if (phydev->link) {
1235 
1236 		if ((greth->speed != phydev->speed) || (greth->duplex != phydev->duplex)) {
1237 			ctrl = GRETH_REGLOAD(greth->regs->control) &
1238 			       ~(GRETH_CTRL_FD | GRETH_CTRL_SP | GRETH_CTRL_GB);
1239 
1240 			if (phydev->duplex)
1241 				ctrl |= GRETH_CTRL_FD;
1242 
1243 			if (phydev->speed == SPEED_100)
1244 				ctrl |= GRETH_CTRL_SP;
1245 			else if (phydev->speed == SPEED_1000)
1246 				ctrl |= GRETH_CTRL_GB;
1247 
1248 			GRETH_REGSAVE(greth->regs->control, ctrl);
1249 			greth->speed = phydev->speed;
1250 			greth->duplex = phydev->duplex;
1251 			status_change = 1;
1252 		}
1253 	}
1254 
1255 	if (phydev->link != greth->link) {
1256 		if (!phydev->link) {
1257 			greth->speed = 0;
1258 			greth->duplex = -1;
1259 		}
1260 		greth->link = phydev->link;
1261 
1262 		status_change = 1;
1263 	}
1264 
1265 	spin_unlock_irqrestore(&greth->devlock, flags);
1266 
1267 	if (status_change) {
1268 		if (phydev->link)
1269 			pr_debug("%s: link up (%d/%s)\n",
1270 				dev->name, phydev->speed,
1271 				DUPLEX_FULL == phydev->duplex ? "Full" : "Half");
1272 		else
1273 			pr_debug("%s: link down\n", dev->name);
1274 	}
1275 }
1276 
1277 static int greth_mdio_probe(struct net_device *dev)
1278 {
1279 	struct greth_private *greth = netdev_priv(dev);
1280 	struct phy_device *phy = NULL;
1281 	int ret;
1282 
1283 	/* Find the first PHY */
1284 	phy = phy_find_first(greth->mdio);
1285 
1286 	if (!phy) {
1287 		if (netif_msg_probe(greth))
1288 			dev_err(&dev->dev, "no PHY found\n");
1289 		return -ENXIO;
1290 	}
1291 
1292 	ret = phy_connect_direct(dev, phy, &greth_link_change,
1293 				 greth->gbit_mac ? PHY_INTERFACE_MODE_GMII : PHY_INTERFACE_MODE_MII);
1294 	if (ret) {
1295 		if (netif_msg_ifup(greth))
1296 			dev_err(&dev->dev, "could not attach to PHY\n");
1297 		return ret;
1298 	}
1299 
1300 	if (greth->gbit_mac)
1301 		phy->supported &= PHY_GBIT_FEATURES;
1302 	else
1303 		phy->supported &= PHY_BASIC_FEATURES;
1304 
1305 	phy->advertising = phy->supported;
1306 
1307 	greth->link = 0;
1308 	greth->speed = 0;
1309 	greth->duplex = -1;
1310 	greth->phy = phy;
1311 
1312 	return 0;
1313 }
1314 
1315 static inline int phy_aneg_done(struct phy_device *phydev)
1316 {
1317 	int retval;
1318 
1319 	retval = phy_read(phydev, MII_BMSR);
1320 
1321 	return (retval < 0) ? retval : (retval & BMSR_ANEGCOMPLETE);
1322 }
1323 
1324 static int greth_mdio_init(struct greth_private *greth)
1325 {
1326 	int ret, phy;
1327 	unsigned long timeout;
1328 
1329 	greth->mdio = mdiobus_alloc();
1330 	if (!greth->mdio) {
1331 		return -ENOMEM;
1332 	}
1333 
1334 	greth->mdio->name = "greth-mdio";
1335 	snprintf(greth->mdio->id, MII_BUS_ID_SIZE, "%s-%d", greth->mdio->name, greth->irq);
1336 	greth->mdio->read = greth_mdio_read;
1337 	greth->mdio->write = greth_mdio_write;
1338 	greth->mdio->priv = greth;
1339 
1340 	greth->mdio->irq = greth->mdio_irqs;
1341 
1342 	for (phy = 0; phy < PHY_MAX_ADDR; phy++)
1343 		greth->mdio->irq[phy] = PHY_POLL;
1344 
1345 	ret = mdiobus_register(greth->mdio);
1346 	if (ret) {
1347 		goto error;
1348 	}
1349 
1350 	ret = greth_mdio_probe(greth->netdev);
1351 	if (ret) {
1352 		if (netif_msg_probe(greth))
1353 			dev_err(&greth->netdev->dev, "failed to probe MDIO bus\n");
1354 		goto unreg_mdio;
1355 	}
1356 
1357 	phy_start(greth->phy);
1358 
1359 	/* If Ethernet debug link is used make autoneg happen right away */
1360 	if (greth->edcl && greth_edcl == 1) {
1361 		phy_start_aneg(greth->phy);
1362 		timeout = jiffies + 6*HZ;
1363 		while (!phy_aneg_done(greth->phy) && time_before(jiffies, timeout)) {
1364 		}
1365 		phy_read_status(greth->phy);
1366 		greth_link_change(greth->netdev);
1367 	}
1368 
1369 	return 0;
1370 
1371 unreg_mdio:
1372 	mdiobus_unregister(greth->mdio);
1373 error:
1374 	mdiobus_free(greth->mdio);
1375 	return ret;
1376 }
1377 
1378 /* Initialize the GRETH MAC */
1379 static int greth_of_probe(struct platform_device *ofdev)
1380 {
1381 	struct net_device *dev;
1382 	struct greth_private *greth;
1383 	struct greth_regs *regs;
1384 
1385 	int i;
1386 	int err;
1387 	int tmp;
1388 	unsigned long timeout;
1389 
1390 	dev = alloc_etherdev(sizeof(struct greth_private));
1391 
1392 	if (dev == NULL)
1393 		return -ENOMEM;
1394 
1395 	greth = netdev_priv(dev);
1396 	greth->netdev = dev;
1397 	greth->dev = &ofdev->dev;
1398 
1399 	if (greth_debug > 0)
1400 		greth->msg_enable = greth_debug;
1401 	else
1402 		greth->msg_enable = GRETH_DEF_MSG_ENABLE;
1403 
1404 	spin_lock_init(&greth->devlock);
1405 
1406 	greth->regs = of_ioremap(&ofdev->resource[0], 0,
1407 				 resource_size(&ofdev->resource[0]),
1408 				 "grlib-greth regs");
1409 
1410 	if (greth->regs == NULL) {
1411 		if (netif_msg_probe(greth))
1412 			dev_err(greth->dev, "ioremap failure.\n");
1413 		err = -EIO;
1414 		goto error1;
1415 	}
1416 
1417 	regs = greth->regs;
1418 	greth->irq = ofdev->archdata.irqs[0];
1419 
1420 	dev_set_drvdata(greth->dev, dev);
1421 	SET_NETDEV_DEV(dev, greth->dev);
1422 
1423 	if (netif_msg_probe(greth))
1424 		dev_dbg(greth->dev, "resetting controller.\n");
1425 
1426 	/* Reset the controller. */
1427 	GRETH_REGSAVE(regs->control, GRETH_RESET);
1428 
1429 	/* Wait for MAC to reset itself */
1430 	timeout = jiffies + HZ/100;
1431 	while (GRETH_REGLOAD(regs->control) & GRETH_RESET) {
1432 		if (time_after(jiffies, timeout)) {
1433 			err = -EIO;
1434 			if (netif_msg_probe(greth))
1435 				dev_err(greth->dev, "timeout when waiting for reset.\n");
1436 			goto error2;
1437 		}
1438 	}
1439 
1440 	/* Get default PHY address  */
1441 	greth->phyaddr = (GRETH_REGLOAD(regs->mdio) >> 11) & 0x1F;
1442 
1443 	/* Check if we have GBIT capable MAC */
1444 	tmp = GRETH_REGLOAD(regs->control);
1445 	greth->gbit_mac = (tmp >> 27) & 1;
1446 
1447 	/* Check for multicast capability */
1448 	greth->multicast = (tmp >> 25) & 1;
1449 
1450 	greth->edcl = (tmp >> 31) & 1;
1451 
1452 	/* If we have EDCL we disable the EDCL speed-duplex FSM so
1453 	 * it doesn't interfere with the software */
1454 	if (greth->edcl != 0)
1455 		GRETH_REGORIN(regs->control, GRETH_CTRL_DISDUPLEX);
1456 
1457 	/* Check if MAC can handle MDIO interrupts */
1458 	greth->mdio_int_en = (tmp >> 26) & 1;
1459 
1460 	err = greth_mdio_init(greth);
1461 	if (err) {
1462 		if (netif_msg_probe(greth))
1463 			dev_err(greth->dev, "failed to register MDIO bus\n");
1464 		goto error2;
1465 	}
1466 
1467 	/* Allocate TX descriptor ring in coherent memory */
1468 	greth->tx_bd_base = dma_zalloc_coherent(greth->dev, 1024,
1469 						&greth->tx_bd_base_phys,
1470 						GFP_KERNEL);
1471 	if (!greth->tx_bd_base) {
1472 		err = -ENOMEM;
1473 		goto error3;
1474 	}
1475 
1476 	/* Allocate RX descriptor ring in coherent memory */
1477 	greth->rx_bd_base = dma_zalloc_coherent(greth->dev, 1024,
1478 						&greth->rx_bd_base_phys,
1479 						GFP_KERNEL);
1480 	if (!greth->rx_bd_base) {
1481 		err = -ENOMEM;
1482 		goto error4;
1483 	}
1484 
1485 	/* Get MAC address from: module param, OF property or ID prom */
1486 	for (i = 0; i < 6; i++) {
1487 		if (macaddr[i] != 0)
1488 			break;
1489 	}
1490 	if (i == 6) {
1491 		const unsigned char *addr;
1492 		int len;
1493 		addr = of_get_property(ofdev->dev.of_node, "local-mac-address",
1494 					&len);
1495 		if (addr != NULL && len == 6) {
1496 			for (i = 0; i < 6; i++)
1497 				macaddr[i] = (unsigned int) addr[i];
1498 		} else {
1499 #ifdef CONFIG_SPARC
1500 			for (i = 0; i < 6; i++)
1501 				macaddr[i] = (unsigned int) idprom->id_ethaddr[i];
1502 #endif
1503 		}
1504 	}
1505 
1506 	for (i = 0; i < 6; i++)
1507 		dev->dev_addr[i] = macaddr[i];
1508 
1509 	macaddr[5]++;
1510 
1511 	if (!is_valid_ether_addr(&dev->dev_addr[0])) {
1512 		if (netif_msg_probe(greth))
1513 			dev_err(greth->dev, "no valid ethernet address, aborting.\n");
1514 		err = -EINVAL;
1515 		goto error5;
1516 	}
1517 
1518 	GRETH_REGSAVE(regs->esa_msb, dev->dev_addr[0] << 8 | dev->dev_addr[1]);
1519 	GRETH_REGSAVE(regs->esa_lsb, dev->dev_addr[2] << 24 | dev->dev_addr[3] << 16 |
1520 		      dev->dev_addr[4] << 8 | dev->dev_addr[5]);
1521 
1522 	/* Clear all pending interrupts except PHY irq */
1523 	GRETH_REGSAVE(regs->status, 0xFF);
1524 
1525 	if (greth->gbit_mac) {
1526 		dev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM |
1527 			NETIF_F_RXCSUM;
1528 		dev->features = dev->hw_features | NETIF_F_HIGHDMA;
1529 		greth_netdev_ops.ndo_start_xmit = greth_start_xmit_gbit;
1530 	}
1531 
1532 	if (greth->multicast) {
1533 		greth_netdev_ops.ndo_set_rx_mode = greth_set_multicast_list;
1534 		dev->flags |= IFF_MULTICAST;
1535 	} else {
1536 		dev->flags &= ~IFF_MULTICAST;
1537 	}
1538 
1539 	dev->netdev_ops = &greth_netdev_ops;
1540 	dev->ethtool_ops = &greth_ethtool_ops;
1541 
1542 	err = register_netdev(dev);
1543 	if (err) {
1544 		if (netif_msg_probe(greth))
1545 			dev_err(greth->dev, "netdevice registration failed.\n");
1546 		goto error5;
1547 	}
1548 
1549 	/* setup NAPI */
1550 	netif_napi_add(dev, &greth->napi, greth_poll, 64);
1551 
1552 	return 0;
1553 
1554 error5:
1555 	dma_free_coherent(greth->dev, 1024, greth->rx_bd_base, greth->rx_bd_base_phys);
1556 error4:
1557 	dma_free_coherent(greth->dev, 1024, greth->tx_bd_base, greth->tx_bd_base_phys);
1558 error3:
1559 	mdiobus_unregister(greth->mdio);
1560 error2:
1561 	of_iounmap(&ofdev->resource[0], greth->regs, resource_size(&ofdev->resource[0]));
1562 error1:
1563 	free_netdev(dev);
1564 	return err;
1565 }
1566 
1567 static int greth_of_remove(struct platform_device *of_dev)
1568 {
1569 	struct net_device *ndev = platform_get_drvdata(of_dev);
1570 	struct greth_private *greth = netdev_priv(ndev);
1571 
1572 	/* Free descriptor areas */
1573 	dma_free_coherent(&of_dev->dev, 1024, greth->rx_bd_base, greth->rx_bd_base_phys);
1574 
1575 	dma_free_coherent(&of_dev->dev, 1024, greth->tx_bd_base, greth->tx_bd_base_phys);
1576 
1577 	if (greth->phy)
1578 		phy_stop(greth->phy);
1579 	mdiobus_unregister(greth->mdio);
1580 
1581 	unregister_netdev(ndev);
1582 	free_netdev(ndev);
1583 
1584 	of_iounmap(&of_dev->resource[0], greth->regs, resource_size(&of_dev->resource[0]));
1585 
1586 	return 0;
1587 }
1588 
1589 static const struct of_device_id greth_of_match[] = {
1590 	{
1591 	 .name = "GAISLER_ETHMAC",
1592 	 },
1593 	{
1594 	 .name = "01_01d",
1595 	 },
1596 	{},
1597 };
1598 
1599 MODULE_DEVICE_TABLE(of, greth_of_match);
1600 
1601 static struct platform_driver greth_of_driver = {
1602 	.driver = {
1603 		.name = "grlib-greth",
1604 		.of_match_table = greth_of_match,
1605 	},
1606 	.probe = greth_of_probe,
1607 	.remove = greth_of_remove,
1608 };
1609 
1610 module_platform_driver(greth_of_driver);
1611 
1612 MODULE_AUTHOR("Aeroflex Gaisler AB.");
1613 MODULE_DESCRIPTION("Aeroflex Gaisler Ethernet MAC driver");
1614 MODULE_LICENSE("GPL");
1615