1 /*
2  * Combined Ethernet driver for Motorola MPC8xx and MPC82xx.
3  *
4  * Copyright (c) 2003 Intracom S.A.
5  *  by Pantelis Antoniou <panto@intracom.gr>
6  *
7  * 2005 (c) MontaVista Software, Inc.
8  * Vitaly Bordug <vbordug@ru.mvista.com>
9  *
10  * Heavily based on original FEC driver by Dan Malek <dan@embeddededge.com>
11  * and modifications by Joakim Tjernlund <joakim.tjernlund@lumentis.se>
12  *
13  * This file is licensed under the terms of the GNU General Public License
14  * version 2. This program is licensed "as is" without any warranty of any
15  * kind, whether express or implied.
16  */
17 
18 #include <linux/module.h>
19 #include <linux/kernel.h>
20 #include <linux/types.h>
21 #include <linux/string.h>
22 #include <linux/ptrace.h>
23 #include <linux/errno.h>
24 #include <linux/ioport.h>
25 #include <linux/slab.h>
26 #include <linux/interrupt.h>
27 #include <linux/delay.h>
28 #include <linux/netdevice.h>
29 #include <linux/etherdevice.h>
30 #include <linux/skbuff.h>
31 #include <linux/spinlock.h>
32 #include <linux/mii.h>
33 #include <linux/ethtool.h>
34 #include <linux/bitops.h>
35 #include <linux/fs.h>
36 #include <linux/platform_device.h>
37 #include <linux/phy.h>
38 #include <linux/of.h>
39 #include <linux/of_mdio.h>
40 #include <linux/of_platform.h>
41 #include <linux/of_gpio.h>
42 #include <linux/of_net.h>
43 
44 #include <linux/vmalloc.h>
45 #include <asm/pgtable.h>
46 #include <asm/irq.h>
47 #include <asm/uaccess.h>
48 
49 #include "fs_enet.h"
50 
51 /*************************************************/
52 
53 MODULE_AUTHOR("Pantelis Antoniou <panto@intracom.gr>");
54 MODULE_DESCRIPTION("Freescale Ethernet Driver");
55 MODULE_LICENSE("GPL");
56 MODULE_VERSION(DRV_MODULE_VERSION);
57 
58 static int fs_enet_debug = -1; /* -1 == use FS_ENET_DEF_MSG_ENABLE as value */
59 module_param(fs_enet_debug, int, 0);
60 MODULE_PARM_DESC(fs_enet_debug,
61 		 "Freescale bitmapped debugging message enable value");
62 
63 #ifdef CONFIG_NET_POLL_CONTROLLER
64 static void fs_enet_netpoll(struct net_device *dev);
65 #endif
66 
67 static void fs_set_multicast_list(struct net_device *dev)
68 {
69 	struct fs_enet_private *fep = netdev_priv(dev);
70 
71 	(*fep->ops->set_multicast_list)(dev);
72 }
73 
74 static void skb_align(struct sk_buff *skb, int align)
75 {
76 	int off = ((unsigned long)skb->data) & (align - 1);
77 
78 	if (off)
79 		skb_reserve(skb, align - off);
80 }
81 
82 /* NAPI receive function */
83 static int fs_enet_rx_napi(struct napi_struct *napi, int budget)
84 {
85 	struct fs_enet_private *fep = container_of(napi, struct fs_enet_private, napi);
86 	struct net_device *dev = fep->ndev;
87 	const struct fs_platform_info *fpi = fep->fpi;
88 	cbd_t __iomem *bdp;
89 	struct sk_buff *skb, *skbn, *skbt;
90 	int received = 0;
91 	u16 pkt_len, sc;
92 	int curidx;
93 
94 	if (budget <= 0)
95 		return received;
96 
97 	/*
98 	 * First, grab all of the stats for the incoming packet.
99 	 * These get messed up if we get called due to a busy condition.
100 	 */
101 	bdp = fep->cur_rx;
102 
103 	/* clear RX status bits for napi*/
104 	(*fep->ops->napi_clear_rx_event)(dev);
105 
106 	while (((sc = CBDR_SC(bdp)) & BD_ENET_RX_EMPTY) == 0) {
107 		curidx = bdp - fep->rx_bd_base;
108 
109 		/*
110 		 * Since we have allocated space to hold a complete frame,
111 		 * the last indicator should be set.
112 		 */
113 		if ((sc & BD_ENET_RX_LAST) == 0)
114 			dev_warn(fep->dev, "rcv is not +last\n");
115 
116 		/*
117 		 * Check for errors.
118 		 */
119 		if (sc & (BD_ENET_RX_LG | BD_ENET_RX_SH | BD_ENET_RX_CL |
120 			  BD_ENET_RX_NO | BD_ENET_RX_CR | BD_ENET_RX_OV)) {
121 			fep->stats.rx_errors++;
122 			/* Frame too long or too short. */
123 			if (sc & (BD_ENET_RX_LG | BD_ENET_RX_SH))
124 				fep->stats.rx_length_errors++;
125 			/* Frame alignment */
126 			if (sc & (BD_ENET_RX_NO | BD_ENET_RX_CL))
127 				fep->stats.rx_frame_errors++;
128 			/* CRC Error */
129 			if (sc & BD_ENET_RX_CR)
130 				fep->stats.rx_crc_errors++;
131 			/* FIFO overrun */
132 			if (sc & BD_ENET_RX_OV)
133 				fep->stats.rx_crc_errors++;
134 
135 			skb = fep->rx_skbuff[curidx];
136 
137 			dma_unmap_single(fep->dev, CBDR_BUFADDR(bdp),
138 				L1_CACHE_ALIGN(PKT_MAXBUF_SIZE),
139 				DMA_FROM_DEVICE);
140 
141 			skbn = skb;
142 
143 		} else {
144 			skb = fep->rx_skbuff[curidx];
145 
146 			dma_unmap_single(fep->dev, CBDR_BUFADDR(bdp),
147 				L1_CACHE_ALIGN(PKT_MAXBUF_SIZE),
148 				DMA_FROM_DEVICE);
149 
150 			/*
151 			 * Process the incoming frame.
152 			 */
153 			fep->stats.rx_packets++;
154 			pkt_len = CBDR_DATLEN(bdp) - 4;	/* remove CRC */
155 			fep->stats.rx_bytes += pkt_len + 4;
156 
157 			if (pkt_len <= fpi->rx_copybreak) {
158 				/* +2 to make IP header L1 cache aligned */
159 				skbn = netdev_alloc_skb(dev, pkt_len + 2);
160 				if (skbn != NULL) {
161 					skb_reserve(skbn, 2);	/* align IP header */
162 					skb_copy_from_linear_data(skb,
163 						      skbn->data, pkt_len);
164 					/* swap */
165 					skbt = skb;
166 					skb = skbn;
167 					skbn = skbt;
168 				}
169 			} else {
170 				skbn = netdev_alloc_skb(dev, ENET_RX_FRSIZE);
171 
172 				if (skbn)
173 					skb_align(skbn, ENET_RX_ALIGN);
174 			}
175 
176 			if (skbn != NULL) {
177 				skb_put(skb, pkt_len);	/* Make room */
178 				skb->protocol = eth_type_trans(skb, dev);
179 				received++;
180 				netif_receive_skb(skb);
181 			} else {
182 				fep->stats.rx_dropped++;
183 				skbn = skb;
184 			}
185 		}
186 
187 		fep->rx_skbuff[curidx] = skbn;
188 		CBDW_BUFADDR(bdp, dma_map_single(fep->dev, skbn->data,
189 			     L1_CACHE_ALIGN(PKT_MAXBUF_SIZE),
190 			     DMA_FROM_DEVICE));
191 		CBDW_DATLEN(bdp, 0);
192 		CBDW_SC(bdp, (sc & ~BD_ENET_RX_STATS) | BD_ENET_RX_EMPTY);
193 
194 		/*
195 		 * Update BD pointer to next entry.
196 		 */
197 		if ((sc & BD_ENET_RX_WRAP) == 0)
198 			bdp++;
199 		else
200 			bdp = fep->rx_bd_base;
201 
202 		(*fep->ops->rx_bd_done)(dev);
203 
204 		if (received >= budget)
205 			break;
206 	}
207 
208 	fep->cur_rx = bdp;
209 
210 	if (received < budget) {
211 		/* done */
212 		napi_complete(napi);
213 		(*fep->ops->napi_enable_rx)(dev);
214 	}
215 	return received;
216 }
217 
218 /* non NAPI receive function */
219 static int fs_enet_rx_non_napi(struct net_device *dev)
220 {
221 	struct fs_enet_private *fep = netdev_priv(dev);
222 	const struct fs_platform_info *fpi = fep->fpi;
223 	cbd_t __iomem *bdp;
224 	struct sk_buff *skb, *skbn, *skbt;
225 	int received = 0;
226 	u16 pkt_len, sc;
227 	int curidx;
228 	/*
229 	 * First, grab all of the stats for the incoming packet.
230 	 * These get messed up if we get called due to a busy condition.
231 	 */
232 	bdp = fep->cur_rx;
233 
234 	while (((sc = CBDR_SC(bdp)) & BD_ENET_RX_EMPTY) == 0) {
235 
236 		curidx = bdp - fep->rx_bd_base;
237 
238 		/*
239 		 * Since we have allocated space to hold a complete frame,
240 		 * the last indicator should be set.
241 		 */
242 		if ((sc & BD_ENET_RX_LAST) == 0)
243 			dev_warn(fep->dev, "rcv is not +last\n");
244 
245 		/*
246 		 * Check for errors.
247 		 */
248 		if (sc & (BD_ENET_RX_LG | BD_ENET_RX_SH | BD_ENET_RX_CL |
249 			  BD_ENET_RX_NO | BD_ENET_RX_CR | BD_ENET_RX_OV)) {
250 			fep->stats.rx_errors++;
251 			/* Frame too long or too short. */
252 			if (sc & (BD_ENET_RX_LG | BD_ENET_RX_SH))
253 				fep->stats.rx_length_errors++;
254 			/* Frame alignment */
255 			if (sc & (BD_ENET_RX_NO | BD_ENET_RX_CL))
256 				fep->stats.rx_frame_errors++;
257 			/* CRC Error */
258 			if (sc & BD_ENET_RX_CR)
259 				fep->stats.rx_crc_errors++;
260 			/* FIFO overrun */
261 			if (sc & BD_ENET_RX_OV)
262 				fep->stats.rx_crc_errors++;
263 
264 			skb = fep->rx_skbuff[curidx];
265 
266 			dma_unmap_single(fep->dev, CBDR_BUFADDR(bdp),
267 				L1_CACHE_ALIGN(PKT_MAXBUF_SIZE),
268 				DMA_FROM_DEVICE);
269 
270 			skbn = skb;
271 
272 		} else {
273 
274 			skb = fep->rx_skbuff[curidx];
275 
276 			dma_unmap_single(fep->dev, CBDR_BUFADDR(bdp),
277 				L1_CACHE_ALIGN(PKT_MAXBUF_SIZE),
278 				DMA_FROM_DEVICE);
279 
280 			/*
281 			 * Process the incoming frame.
282 			 */
283 			fep->stats.rx_packets++;
284 			pkt_len = CBDR_DATLEN(bdp) - 4;	/* remove CRC */
285 			fep->stats.rx_bytes += pkt_len + 4;
286 
287 			if (pkt_len <= fpi->rx_copybreak) {
288 				/* +2 to make IP header L1 cache aligned */
289 				skbn = netdev_alloc_skb(dev, pkt_len + 2);
290 				if (skbn != NULL) {
291 					skb_reserve(skbn, 2);	/* align IP header */
292 					skb_copy_from_linear_data(skb,
293 						      skbn->data, pkt_len);
294 					/* swap */
295 					skbt = skb;
296 					skb = skbn;
297 					skbn = skbt;
298 				}
299 			} else {
300 				skbn = netdev_alloc_skb(dev, ENET_RX_FRSIZE);
301 
302 				if (skbn)
303 					skb_align(skbn, ENET_RX_ALIGN);
304 			}
305 
306 			if (skbn != NULL) {
307 				skb_put(skb, pkt_len);	/* Make room */
308 				skb->protocol = eth_type_trans(skb, dev);
309 				received++;
310 				netif_rx(skb);
311 			} else {
312 				fep->stats.rx_dropped++;
313 				skbn = skb;
314 			}
315 		}
316 
317 		fep->rx_skbuff[curidx] = skbn;
318 		CBDW_BUFADDR(bdp, dma_map_single(fep->dev, skbn->data,
319 			     L1_CACHE_ALIGN(PKT_MAXBUF_SIZE),
320 			     DMA_FROM_DEVICE));
321 		CBDW_DATLEN(bdp, 0);
322 		CBDW_SC(bdp, (sc & ~BD_ENET_RX_STATS) | BD_ENET_RX_EMPTY);
323 
324 		/*
325 		 * Update BD pointer to next entry.
326 		 */
327 		if ((sc & BD_ENET_RX_WRAP) == 0)
328 			bdp++;
329 		else
330 			bdp = fep->rx_bd_base;
331 
332 		(*fep->ops->rx_bd_done)(dev);
333 	}
334 
335 	fep->cur_rx = bdp;
336 
337 	return 0;
338 }
339 
340 static void fs_enet_tx(struct net_device *dev)
341 {
342 	struct fs_enet_private *fep = netdev_priv(dev);
343 	cbd_t __iomem *bdp;
344 	struct sk_buff *skb;
345 	int dirtyidx, do_wake, do_restart;
346 	u16 sc;
347 
348 	spin_lock(&fep->tx_lock);
349 	bdp = fep->dirty_tx;
350 
351 	do_wake = do_restart = 0;
352 	while (((sc = CBDR_SC(bdp)) & BD_ENET_TX_READY) == 0) {
353 		dirtyidx = bdp - fep->tx_bd_base;
354 
355 		if (fep->tx_free == fep->tx_ring)
356 			break;
357 
358 		skb = fep->tx_skbuff[dirtyidx];
359 
360 		/*
361 		 * Check for errors.
362 		 */
363 		if (sc & (BD_ENET_TX_HB | BD_ENET_TX_LC |
364 			  BD_ENET_TX_RL | BD_ENET_TX_UN | BD_ENET_TX_CSL)) {
365 
366 			if (sc & BD_ENET_TX_HB)	/* No heartbeat */
367 				fep->stats.tx_heartbeat_errors++;
368 			if (sc & BD_ENET_TX_LC)	/* Late collision */
369 				fep->stats.tx_window_errors++;
370 			if (sc & BD_ENET_TX_RL)	/* Retrans limit */
371 				fep->stats.tx_aborted_errors++;
372 			if (sc & BD_ENET_TX_UN)	/* Underrun */
373 				fep->stats.tx_fifo_errors++;
374 			if (sc & BD_ENET_TX_CSL)	/* Carrier lost */
375 				fep->stats.tx_carrier_errors++;
376 
377 			if (sc & (BD_ENET_TX_LC | BD_ENET_TX_RL | BD_ENET_TX_UN)) {
378 				fep->stats.tx_errors++;
379 				do_restart = 1;
380 			}
381 		} else
382 			fep->stats.tx_packets++;
383 
384 		if (sc & BD_ENET_TX_READY) {
385 			dev_warn(fep->dev,
386 				 "HEY! Enet xmit interrupt and TX_READY.\n");
387 		}
388 
389 		/*
390 		 * Deferred means some collisions occurred during transmit,
391 		 * but we eventually sent the packet OK.
392 		 */
393 		if (sc & BD_ENET_TX_DEF)
394 			fep->stats.collisions++;
395 
396 		/* unmap */
397 		dma_unmap_single(fep->dev, CBDR_BUFADDR(bdp),
398 				skb->len, DMA_TO_DEVICE);
399 
400 		/*
401 		 * Free the sk buffer associated with this last transmit.
402 		 */
403 		dev_kfree_skb_irq(skb);
404 		fep->tx_skbuff[dirtyidx] = NULL;
405 
406 		/*
407 		 * Update pointer to next buffer descriptor to be transmitted.
408 		 */
409 		if ((sc & BD_ENET_TX_WRAP) == 0)
410 			bdp++;
411 		else
412 			bdp = fep->tx_bd_base;
413 
414 		/*
415 		 * Since we have freed up a buffer, the ring is no longer
416 		 * full.
417 		 */
418 		if (!fep->tx_free++)
419 			do_wake = 1;
420 	}
421 
422 	fep->dirty_tx = bdp;
423 
424 	if (do_restart)
425 		(*fep->ops->tx_restart)(dev);
426 
427 	spin_unlock(&fep->tx_lock);
428 
429 	if (do_wake)
430 		netif_wake_queue(dev);
431 }
432 
433 /*
434  * The interrupt handler.
435  * This is called from the MPC core interrupt.
436  */
437 static irqreturn_t
438 fs_enet_interrupt(int irq, void *dev_id)
439 {
440 	struct net_device *dev = dev_id;
441 	struct fs_enet_private *fep;
442 	const struct fs_platform_info *fpi;
443 	u32 int_events;
444 	u32 int_clr_events;
445 	int nr, napi_ok;
446 	int handled;
447 
448 	fep = netdev_priv(dev);
449 	fpi = fep->fpi;
450 
451 	nr = 0;
452 	while ((int_events = (*fep->ops->get_int_events)(dev)) != 0) {
453 		nr++;
454 
455 		int_clr_events = int_events;
456 		if (fpi->use_napi)
457 			int_clr_events &= ~fep->ev_napi_rx;
458 
459 		(*fep->ops->clear_int_events)(dev, int_clr_events);
460 
461 		if (int_events & fep->ev_err)
462 			(*fep->ops->ev_error)(dev, int_events);
463 
464 		if (int_events & fep->ev_rx) {
465 			if (!fpi->use_napi)
466 				fs_enet_rx_non_napi(dev);
467 			else {
468 				napi_ok = napi_schedule_prep(&fep->napi);
469 
470 				(*fep->ops->napi_disable_rx)(dev);
471 				(*fep->ops->clear_int_events)(dev, fep->ev_napi_rx);
472 
473 				/* NOTE: it is possible for FCCs in NAPI mode    */
474 				/* to submit a spurious interrupt while in poll  */
475 				if (napi_ok)
476 					__napi_schedule(&fep->napi);
477 			}
478 		}
479 
480 		if (int_events & fep->ev_tx)
481 			fs_enet_tx(dev);
482 	}
483 
484 	handled = nr > 0;
485 	return IRQ_RETVAL(handled);
486 }
487 
488 void fs_init_bds(struct net_device *dev)
489 {
490 	struct fs_enet_private *fep = netdev_priv(dev);
491 	cbd_t __iomem *bdp;
492 	struct sk_buff *skb;
493 	int i;
494 
495 	fs_cleanup_bds(dev);
496 
497 	fep->dirty_tx = fep->cur_tx = fep->tx_bd_base;
498 	fep->tx_free = fep->tx_ring;
499 	fep->cur_rx = fep->rx_bd_base;
500 
501 	/*
502 	 * Initialize the receive buffer descriptors.
503 	 */
504 	for (i = 0, bdp = fep->rx_bd_base; i < fep->rx_ring; i++, bdp++) {
505 		skb = netdev_alloc_skb(dev, ENET_RX_FRSIZE);
506 		if (skb == NULL)
507 			break;
508 
509 		skb_align(skb, ENET_RX_ALIGN);
510 		fep->rx_skbuff[i] = skb;
511 		CBDW_BUFADDR(bdp,
512 			dma_map_single(fep->dev, skb->data,
513 				L1_CACHE_ALIGN(PKT_MAXBUF_SIZE),
514 				DMA_FROM_DEVICE));
515 		CBDW_DATLEN(bdp, 0);	/* zero */
516 		CBDW_SC(bdp, BD_ENET_RX_EMPTY |
517 			((i < fep->rx_ring - 1) ? 0 : BD_SC_WRAP));
518 	}
519 	/*
520 	 * if we failed, fillup remainder
521 	 */
522 	for (; i < fep->rx_ring; i++, bdp++) {
523 		fep->rx_skbuff[i] = NULL;
524 		CBDW_SC(bdp, (i < fep->rx_ring - 1) ? 0 : BD_SC_WRAP);
525 	}
526 
527 	/*
528 	 * ...and the same for transmit.
529 	 */
530 	for (i = 0, bdp = fep->tx_bd_base; i < fep->tx_ring; i++, bdp++) {
531 		fep->tx_skbuff[i] = NULL;
532 		CBDW_BUFADDR(bdp, 0);
533 		CBDW_DATLEN(bdp, 0);
534 		CBDW_SC(bdp, (i < fep->tx_ring - 1) ? 0 : BD_SC_WRAP);
535 	}
536 }
537 
538 void fs_cleanup_bds(struct net_device *dev)
539 {
540 	struct fs_enet_private *fep = netdev_priv(dev);
541 	struct sk_buff *skb;
542 	cbd_t __iomem *bdp;
543 	int i;
544 
545 	/*
546 	 * Reset SKB transmit buffers.
547 	 */
548 	for (i = 0, bdp = fep->tx_bd_base; i < fep->tx_ring; i++, bdp++) {
549 		if ((skb = fep->tx_skbuff[i]) == NULL)
550 			continue;
551 
552 		/* unmap */
553 		dma_unmap_single(fep->dev, CBDR_BUFADDR(bdp),
554 				skb->len, DMA_TO_DEVICE);
555 
556 		fep->tx_skbuff[i] = NULL;
557 		dev_kfree_skb(skb);
558 	}
559 
560 	/*
561 	 * Reset SKB receive buffers
562 	 */
563 	for (i = 0, bdp = fep->rx_bd_base; i < fep->rx_ring; i++, bdp++) {
564 		if ((skb = fep->rx_skbuff[i]) == NULL)
565 			continue;
566 
567 		/* unmap */
568 		dma_unmap_single(fep->dev, CBDR_BUFADDR(bdp),
569 			L1_CACHE_ALIGN(PKT_MAXBUF_SIZE),
570 			DMA_FROM_DEVICE);
571 
572 		fep->rx_skbuff[i] = NULL;
573 
574 		dev_kfree_skb(skb);
575 	}
576 }
577 
578 /**********************************************************************************/
579 
580 #ifdef CONFIG_FS_ENET_MPC5121_FEC
581 /*
582  * MPC5121 FEC requeries 4-byte alignment for TX data buffer!
583  */
584 static struct sk_buff *tx_skb_align_workaround(struct net_device *dev,
585 					       struct sk_buff *skb)
586 {
587 	struct sk_buff *new_skb;
588 
589 	/* Alloc new skb */
590 	new_skb = netdev_alloc_skb(dev, skb->len + 4);
591 	if (!new_skb)
592 		return NULL;
593 
594 	/* Make sure new skb is properly aligned */
595 	skb_align(new_skb, 4);
596 
597 	/* Copy data to new skb ... */
598 	skb_copy_from_linear_data(skb, new_skb->data, skb->len);
599 	skb_put(new_skb, skb->len);
600 
601 	/* ... and free an old one */
602 	dev_kfree_skb_any(skb);
603 
604 	return new_skb;
605 }
606 #endif
607 
608 static int fs_enet_start_xmit(struct sk_buff *skb, struct net_device *dev)
609 {
610 	struct fs_enet_private *fep = netdev_priv(dev);
611 	cbd_t __iomem *bdp;
612 	int curidx;
613 	u16 sc;
614 	unsigned long flags;
615 
616 #ifdef CONFIG_FS_ENET_MPC5121_FEC
617 	if (((unsigned long)skb->data) & 0x3) {
618 		skb = tx_skb_align_workaround(dev, skb);
619 		if (!skb) {
620 			/*
621 			 * We have lost packet due to memory allocation error
622 			 * in tx_skb_align_workaround(). Hopefully original
623 			 * skb is still valid, so try transmit it later.
624 			 */
625 			return NETDEV_TX_BUSY;
626 		}
627 	}
628 #endif
629 	spin_lock_irqsave(&fep->tx_lock, flags);
630 
631 	/*
632 	 * Fill in a Tx ring entry
633 	 */
634 	bdp = fep->cur_tx;
635 
636 	if (!fep->tx_free || (CBDR_SC(bdp) & BD_ENET_TX_READY)) {
637 		netif_stop_queue(dev);
638 		spin_unlock_irqrestore(&fep->tx_lock, flags);
639 
640 		/*
641 		 * Ooops.  All transmit buffers are full.  Bail out.
642 		 * This should not happen, since the tx queue should be stopped.
643 		 */
644 		dev_warn(fep->dev, "tx queue full!.\n");
645 		return NETDEV_TX_BUSY;
646 	}
647 
648 	curidx = bdp - fep->tx_bd_base;
649 	/*
650 	 * Clear all of the status flags.
651 	 */
652 	CBDC_SC(bdp, BD_ENET_TX_STATS);
653 
654 	/*
655 	 * Save skb pointer.
656 	 */
657 	fep->tx_skbuff[curidx] = skb;
658 
659 	fep->stats.tx_bytes += skb->len;
660 
661 	/*
662 	 * Push the data cache so the CPM does not get stale memory data.
663 	 */
664 	CBDW_BUFADDR(bdp, dma_map_single(fep->dev,
665 				skb->data, skb->len, DMA_TO_DEVICE));
666 	CBDW_DATLEN(bdp, skb->len);
667 
668 	/*
669 	 * If this was the last BD in the ring, start at the beginning again.
670 	 */
671 	if ((CBDR_SC(bdp) & BD_ENET_TX_WRAP) == 0)
672 		fep->cur_tx++;
673 	else
674 		fep->cur_tx = fep->tx_bd_base;
675 
676 	if (!--fep->tx_free)
677 		netif_stop_queue(dev);
678 
679 	/* Trigger transmission start */
680 	sc = BD_ENET_TX_READY | BD_ENET_TX_INTR |
681 	     BD_ENET_TX_LAST | BD_ENET_TX_TC;
682 
683 	/* note that while FEC does not have this bit
684 	 * it marks it as available for software use
685 	 * yay for hw reuse :) */
686 	if (skb->len <= 60)
687 		sc |= BD_ENET_TX_PAD;
688 	CBDS_SC(bdp, sc);
689 
690 	skb_tx_timestamp(skb);
691 
692 	(*fep->ops->tx_kickstart)(dev);
693 
694 	spin_unlock_irqrestore(&fep->tx_lock, flags);
695 
696 	return NETDEV_TX_OK;
697 }
698 
699 static void fs_timeout(struct net_device *dev)
700 {
701 	struct fs_enet_private *fep = netdev_priv(dev);
702 	unsigned long flags;
703 	int wake = 0;
704 
705 	fep->stats.tx_errors++;
706 
707 	spin_lock_irqsave(&fep->lock, flags);
708 
709 	if (dev->flags & IFF_UP) {
710 		phy_stop(fep->phydev);
711 		(*fep->ops->stop)(dev);
712 		(*fep->ops->restart)(dev);
713 		phy_start(fep->phydev);
714 	}
715 
716 	phy_start(fep->phydev);
717 	wake = fep->tx_free && !(CBDR_SC(fep->cur_tx) & BD_ENET_TX_READY);
718 	spin_unlock_irqrestore(&fep->lock, flags);
719 
720 	if (wake)
721 		netif_wake_queue(dev);
722 }
723 
724 /*-----------------------------------------------------------------------------
725  *  generic link-change handler - should be sufficient for most cases
726  *-----------------------------------------------------------------------------*/
727 static void generic_adjust_link(struct  net_device *dev)
728 {
729 	struct fs_enet_private *fep = netdev_priv(dev);
730 	struct phy_device *phydev = fep->phydev;
731 	int new_state = 0;
732 
733 	if (phydev->link) {
734 		/* adjust to duplex mode */
735 		if (phydev->duplex != fep->oldduplex) {
736 			new_state = 1;
737 			fep->oldduplex = phydev->duplex;
738 		}
739 
740 		if (phydev->speed != fep->oldspeed) {
741 			new_state = 1;
742 			fep->oldspeed = phydev->speed;
743 		}
744 
745 		if (!fep->oldlink) {
746 			new_state = 1;
747 			fep->oldlink = 1;
748 		}
749 
750 		if (new_state)
751 			fep->ops->restart(dev);
752 	} else if (fep->oldlink) {
753 		new_state = 1;
754 		fep->oldlink = 0;
755 		fep->oldspeed = 0;
756 		fep->oldduplex = -1;
757 	}
758 
759 	if (new_state && netif_msg_link(fep))
760 		phy_print_status(phydev);
761 }
762 
763 
764 static void fs_adjust_link(struct net_device *dev)
765 {
766 	struct fs_enet_private *fep = netdev_priv(dev);
767 	unsigned long flags;
768 
769 	spin_lock_irqsave(&fep->lock, flags);
770 
771 	if(fep->ops->adjust_link)
772 		fep->ops->adjust_link(dev);
773 	else
774 		generic_adjust_link(dev);
775 
776 	spin_unlock_irqrestore(&fep->lock, flags);
777 }
778 
779 static int fs_init_phy(struct net_device *dev)
780 {
781 	struct fs_enet_private *fep = netdev_priv(dev);
782 	struct phy_device *phydev;
783 	phy_interface_t iface;
784 
785 	fep->oldlink = 0;
786 	fep->oldspeed = 0;
787 	fep->oldduplex = -1;
788 
789 	iface = fep->fpi->use_rmii ?
790 		PHY_INTERFACE_MODE_RMII : PHY_INTERFACE_MODE_MII;
791 
792 	phydev = of_phy_connect(dev, fep->fpi->phy_node, &fs_adjust_link, 0,
793 				iface);
794 	if (!phydev) {
795 		dev_err(&dev->dev, "Could not attach to PHY\n");
796 		return -ENODEV;
797 	}
798 
799 	fep->phydev = phydev;
800 
801 	return 0;
802 }
803 
804 static int fs_enet_open(struct net_device *dev)
805 {
806 	struct fs_enet_private *fep = netdev_priv(dev);
807 	int r;
808 	int err;
809 
810 	/* to initialize the fep->cur_rx,... */
811 	/* not doing this, will cause a crash in fs_enet_rx_napi */
812 	fs_init_bds(fep->ndev);
813 
814 	if (fep->fpi->use_napi)
815 		napi_enable(&fep->napi);
816 
817 	/* Install our interrupt handler. */
818 	r = request_irq(fep->interrupt, fs_enet_interrupt, IRQF_SHARED,
819 			"fs_enet-mac", dev);
820 	if (r != 0) {
821 		dev_err(fep->dev, "Could not allocate FS_ENET IRQ!");
822 		if (fep->fpi->use_napi)
823 			napi_disable(&fep->napi);
824 		return -EINVAL;
825 	}
826 
827 	err = fs_init_phy(dev);
828 	if (err) {
829 		free_irq(fep->interrupt, dev);
830 		if (fep->fpi->use_napi)
831 			napi_disable(&fep->napi);
832 		return err;
833 	}
834 	phy_start(fep->phydev);
835 
836 	netif_start_queue(dev);
837 
838 	return 0;
839 }
840 
841 static int fs_enet_close(struct net_device *dev)
842 {
843 	struct fs_enet_private *fep = netdev_priv(dev);
844 	unsigned long flags;
845 
846 	netif_stop_queue(dev);
847 	netif_carrier_off(dev);
848 	if (fep->fpi->use_napi)
849 		napi_disable(&fep->napi);
850 	phy_stop(fep->phydev);
851 
852 	spin_lock_irqsave(&fep->lock, flags);
853 	spin_lock(&fep->tx_lock);
854 	(*fep->ops->stop)(dev);
855 	spin_unlock(&fep->tx_lock);
856 	spin_unlock_irqrestore(&fep->lock, flags);
857 
858 	/* release any irqs */
859 	phy_disconnect(fep->phydev);
860 	fep->phydev = NULL;
861 	free_irq(fep->interrupt, dev);
862 
863 	return 0;
864 }
865 
866 static struct net_device_stats *fs_enet_get_stats(struct net_device *dev)
867 {
868 	struct fs_enet_private *fep = netdev_priv(dev);
869 	return &fep->stats;
870 }
871 
872 /*************************************************************************/
873 
874 static void fs_get_drvinfo(struct net_device *dev,
875 			    struct ethtool_drvinfo *info)
876 {
877 	strlcpy(info->driver, DRV_MODULE_NAME, sizeof(info->driver));
878 	strlcpy(info->version, DRV_MODULE_VERSION, sizeof(info->version));
879 }
880 
881 static int fs_get_regs_len(struct net_device *dev)
882 {
883 	struct fs_enet_private *fep = netdev_priv(dev);
884 
885 	return (*fep->ops->get_regs_len)(dev);
886 }
887 
888 static void fs_get_regs(struct net_device *dev, struct ethtool_regs *regs,
889 			 void *p)
890 {
891 	struct fs_enet_private *fep = netdev_priv(dev);
892 	unsigned long flags;
893 	int r, len;
894 
895 	len = regs->len;
896 
897 	spin_lock_irqsave(&fep->lock, flags);
898 	r = (*fep->ops->get_regs)(dev, p, &len);
899 	spin_unlock_irqrestore(&fep->lock, flags);
900 
901 	if (r == 0)
902 		regs->version = 0;
903 }
904 
905 static int fs_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
906 {
907 	struct fs_enet_private *fep = netdev_priv(dev);
908 
909 	if (!fep->phydev)
910 		return -ENODEV;
911 
912 	return phy_ethtool_gset(fep->phydev, cmd);
913 }
914 
915 static int fs_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
916 {
917 	struct fs_enet_private *fep = netdev_priv(dev);
918 
919 	if (!fep->phydev)
920 		return -ENODEV;
921 
922 	return phy_ethtool_sset(fep->phydev, cmd);
923 }
924 
925 static int fs_nway_reset(struct net_device *dev)
926 {
927 	return 0;
928 }
929 
930 static u32 fs_get_msglevel(struct net_device *dev)
931 {
932 	struct fs_enet_private *fep = netdev_priv(dev);
933 	return fep->msg_enable;
934 }
935 
936 static void fs_set_msglevel(struct net_device *dev, u32 value)
937 {
938 	struct fs_enet_private *fep = netdev_priv(dev);
939 	fep->msg_enable = value;
940 }
941 
942 static const struct ethtool_ops fs_ethtool_ops = {
943 	.get_drvinfo = fs_get_drvinfo,
944 	.get_regs_len = fs_get_regs_len,
945 	.get_settings = fs_get_settings,
946 	.set_settings = fs_set_settings,
947 	.nway_reset = fs_nway_reset,
948 	.get_link = ethtool_op_get_link,
949 	.get_msglevel = fs_get_msglevel,
950 	.set_msglevel = fs_set_msglevel,
951 	.get_regs = fs_get_regs,
952 	.get_ts_info = ethtool_op_get_ts_info,
953 };
954 
955 static int fs_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
956 {
957 	struct fs_enet_private *fep = netdev_priv(dev);
958 
959 	if (!netif_running(dev))
960 		return -EINVAL;
961 
962 	return phy_mii_ioctl(fep->phydev, rq, cmd);
963 }
964 
965 extern int fs_mii_connect(struct net_device *dev);
966 extern void fs_mii_disconnect(struct net_device *dev);
967 
968 /**************************************************************************************/
969 
970 #ifdef CONFIG_FS_ENET_HAS_FEC
971 #define IS_FEC(match) ((match)->data == &fs_fec_ops)
972 #else
973 #define IS_FEC(match) 0
974 #endif
975 
976 static const struct net_device_ops fs_enet_netdev_ops = {
977 	.ndo_open		= fs_enet_open,
978 	.ndo_stop		= fs_enet_close,
979 	.ndo_get_stats		= fs_enet_get_stats,
980 	.ndo_start_xmit		= fs_enet_start_xmit,
981 	.ndo_tx_timeout		= fs_timeout,
982 	.ndo_set_rx_mode	= fs_set_multicast_list,
983 	.ndo_do_ioctl		= fs_ioctl,
984 	.ndo_validate_addr	= eth_validate_addr,
985 	.ndo_set_mac_address	= eth_mac_addr,
986 	.ndo_change_mtu		= eth_change_mtu,
987 #ifdef CONFIG_NET_POLL_CONTROLLER
988 	.ndo_poll_controller	= fs_enet_netpoll,
989 #endif
990 };
991 
992 static struct of_device_id fs_enet_match[];
993 static int fs_enet_probe(struct platform_device *ofdev)
994 {
995 	const struct of_device_id *match;
996 	struct net_device *ndev;
997 	struct fs_enet_private *fep;
998 	struct fs_platform_info *fpi;
999 	const u32 *data;
1000 	struct clk *clk;
1001 	int err;
1002 	const u8 *mac_addr;
1003 	const char *phy_connection_type;
1004 	int privsize, len, ret = -ENODEV;
1005 
1006 	match = of_match_device(fs_enet_match, &ofdev->dev);
1007 	if (!match)
1008 		return -EINVAL;
1009 
1010 	fpi = kzalloc(sizeof(*fpi), GFP_KERNEL);
1011 	if (!fpi)
1012 		return -ENOMEM;
1013 
1014 	if (!IS_FEC(match)) {
1015 		data = of_get_property(ofdev->dev.of_node, "fsl,cpm-command", &len);
1016 		if (!data || len != 4)
1017 			goto out_free_fpi;
1018 
1019 		fpi->cp_command = *data;
1020 	}
1021 
1022 	fpi->rx_ring = 32;
1023 	fpi->tx_ring = 32;
1024 	fpi->rx_copybreak = 240;
1025 	fpi->use_napi = 1;
1026 	fpi->napi_weight = 17;
1027 	fpi->phy_node = of_parse_phandle(ofdev->dev.of_node, "phy-handle", 0);
1028 	if (!fpi->phy_node && of_phy_is_fixed_link(ofdev->dev.of_node)) {
1029 		err = of_phy_register_fixed_link(ofdev->dev.of_node);
1030 		if (err)
1031 			goto out_free_fpi;
1032 
1033 		/* In the case of a fixed PHY, the DT node associated
1034 		 * to the PHY is the Ethernet MAC DT node.
1035 		 */
1036 		fpi->phy_node = ofdev->dev.of_node;
1037 	}
1038 
1039 	if (of_device_is_compatible(ofdev->dev.of_node, "fsl,mpc5125-fec")) {
1040 		phy_connection_type = of_get_property(ofdev->dev.of_node,
1041 						"phy-connection-type", NULL);
1042 		if (phy_connection_type && !strcmp("rmii", phy_connection_type))
1043 			fpi->use_rmii = 1;
1044 	}
1045 
1046 	/* make clock lookup non-fatal (the driver is shared among platforms),
1047 	 * but require enable to succeed when a clock was specified/found,
1048 	 * keep a reference to the clock upon successful acquisition
1049 	 */
1050 	clk = devm_clk_get(&ofdev->dev, "per");
1051 	if (!IS_ERR(clk)) {
1052 		err = clk_prepare_enable(clk);
1053 		if (err) {
1054 			ret = err;
1055 			goto out_free_fpi;
1056 		}
1057 		fpi->clk_per = clk;
1058 	}
1059 
1060 	privsize = sizeof(*fep) +
1061 	           sizeof(struct sk_buff **) *
1062 	           (fpi->rx_ring + fpi->tx_ring);
1063 
1064 	ndev = alloc_etherdev(privsize);
1065 	if (!ndev) {
1066 		ret = -ENOMEM;
1067 		goto out_put;
1068 	}
1069 
1070 	SET_NETDEV_DEV(ndev, &ofdev->dev);
1071 	platform_set_drvdata(ofdev, ndev);
1072 
1073 	fep = netdev_priv(ndev);
1074 	fep->dev = &ofdev->dev;
1075 	fep->ndev = ndev;
1076 	fep->fpi = fpi;
1077 	fep->ops = match->data;
1078 
1079 	ret = fep->ops->setup_data(ndev);
1080 	if (ret)
1081 		goto out_free_dev;
1082 
1083 	fep->rx_skbuff = (struct sk_buff **)&fep[1];
1084 	fep->tx_skbuff = fep->rx_skbuff + fpi->rx_ring;
1085 
1086 	spin_lock_init(&fep->lock);
1087 	spin_lock_init(&fep->tx_lock);
1088 
1089 	mac_addr = of_get_mac_address(ofdev->dev.of_node);
1090 	if (mac_addr)
1091 		memcpy(ndev->dev_addr, mac_addr, ETH_ALEN);
1092 
1093 	ret = fep->ops->allocate_bd(ndev);
1094 	if (ret)
1095 		goto out_cleanup_data;
1096 
1097 	fep->rx_bd_base = fep->ring_base;
1098 	fep->tx_bd_base = fep->rx_bd_base + fpi->rx_ring;
1099 
1100 	fep->tx_ring = fpi->tx_ring;
1101 	fep->rx_ring = fpi->rx_ring;
1102 
1103 	ndev->netdev_ops = &fs_enet_netdev_ops;
1104 	ndev->watchdog_timeo = 2 * HZ;
1105 	if (fpi->use_napi)
1106 		netif_napi_add(ndev, &fep->napi, fs_enet_rx_napi,
1107 		               fpi->napi_weight);
1108 
1109 	ndev->ethtool_ops = &fs_ethtool_ops;
1110 
1111 	init_timer(&fep->phy_timer_list);
1112 
1113 	netif_carrier_off(ndev);
1114 
1115 	ret = register_netdev(ndev);
1116 	if (ret)
1117 		goto out_free_bd;
1118 
1119 	pr_info("%s: fs_enet: %pM\n", ndev->name, ndev->dev_addr);
1120 
1121 	return 0;
1122 
1123 out_free_bd:
1124 	fep->ops->free_bd(ndev);
1125 out_cleanup_data:
1126 	fep->ops->cleanup_data(ndev);
1127 out_free_dev:
1128 	free_netdev(ndev);
1129 out_put:
1130 	of_node_put(fpi->phy_node);
1131 	if (fpi->clk_per)
1132 		clk_disable_unprepare(fpi->clk_per);
1133 out_free_fpi:
1134 	kfree(fpi);
1135 	return ret;
1136 }
1137 
1138 static int fs_enet_remove(struct platform_device *ofdev)
1139 {
1140 	struct net_device *ndev = platform_get_drvdata(ofdev);
1141 	struct fs_enet_private *fep = netdev_priv(ndev);
1142 
1143 	unregister_netdev(ndev);
1144 
1145 	fep->ops->free_bd(ndev);
1146 	fep->ops->cleanup_data(ndev);
1147 	dev_set_drvdata(fep->dev, NULL);
1148 	of_node_put(fep->fpi->phy_node);
1149 	if (fep->fpi->clk_per)
1150 		clk_disable_unprepare(fep->fpi->clk_per);
1151 	free_netdev(ndev);
1152 	return 0;
1153 }
1154 
1155 static struct of_device_id fs_enet_match[] = {
1156 #ifdef CONFIG_FS_ENET_HAS_SCC
1157 	{
1158 		.compatible = "fsl,cpm1-scc-enet",
1159 		.data = (void *)&fs_scc_ops,
1160 	},
1161 	{
1162 		.compatible = "fsl,cpm2-scc-enet",
1163 		.data = (void *)&fs_scc_ops,
1164 	},
1165 #endif
1166 #ifdef CONFIG_FS_ENET_HAS_FCC
1167 	{
1168 		.compatible = "fsl,cpm2-fcc-enet",
1169 		.data = (void *)&fs_fcc_ops,
1170 	},
1171 #endif
1172 #ifdef CONFIG_FS_ENET_HAS_FEC
1173 #ifdef CONFIG_FS_ENET_MPC5121_FEC
1174 	{
1175 		.compatible = "fsl,mpc5121-fec",
1176 		.data = (void *)&fs_fec_ops,
1177 	},
1178 	{
1179 		.compatible = "fsl,mpc5125-fec",
1180 		.data = (void *)&fs_fec_ops,
1181 	},
1182 #else
1183 	{
1184 		.compatible = "fsl,pq1-fec-enet",
1185 		.data = (void *)&fs_fec_ops,
1186 	},
1187 #endif
1188 #endif
1189 	{}
1190 };
1191 MODULE_DEVICE_TABLE(of, fs_enet_match);
1192 
1193 static struct platform_driver fs_enet_driver = {
1194 	.driver = {
1195 		.owner = THIS_MODULE,
1196 		.name = "fs_enet",
1197 		.of_match_table = fs_enet_match,
1198 	},
1199 	.probe = fs_enet_probe,
1200 	.remove = fs_enet_remove,
1201 };
1202 
1203 #ifdef CONFIG_NET_POLL_CONTROLLER
1204 static void fs_enet_netpoll(struct net_device *dev)
1205 {
1206        disable_irq(dev->irq);
1207        fs_enet_interrupt(dev->irq, dev);
1208        enable_irq(dev->irq);
1209 }
1210 #endif
1211 
1212 module_platform_driver(fs_enet_driver);
1213