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