1 /*
2  * EP93xx ethernet network device driver
3  * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
4  * Dedicated to Marija Kulikova.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  */
11 
12 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
13 
14 #include <linux/dma-mapping.h>
15 #include <linux/module.h>
16 #include <linux/kernel.h>
17 #include <linux/netdevice.h>
18 #include <linux/mii.h>
19 #include <linux/etherdevice.h>
20 #include <linux/ethtool.h>
21 #include <linux/interrupt.h>
22 #include <linux/moduleparam.h>
23 #include <linux/platform_device.h>
24 #include <linux/delay.h>
25 #include <linux/io.h>
26 #include <linux/slab.h>
27 
28 #include <mach/hardware.h>
29 
30 #define DRV_MODULE_NAME		"ep93xx-eth"
31 #define DRV_MODULE_VERSION	"0.1"
32 
33 #define RX_QUEUE_ENTRIES	64
34 #define TX_QUEUE_ENTRIES	8
35 
36 #define MAX_PKT_SIZE		2044
37 #define PKT_BUF_SIZE		2048
38 
39 #define REG_RXCTL		0x0000
40 #define  REG_RXCTL_DEFAULT	0x00073800
41 #define REG_TXCTL		0x0004
42 #define  REG_TXCTL_ENABLE	0x00000001
43 #define REG_MIICMD		0x0010
44 #define  REG_MIICMD_READ	0x00008000
45 #define  REG_MIICMD_WRITE	0x00004000
46 #define REG_MIIDATA		0x0014
47 #define REG_MIISTS		0x0018
48 #define  REG_MIISTS_BUSY	0x00000001
49 #define REG_SELFCTL		0x0020
50 #define  REG_SELFCTL_RESET	0x00000001
51 #define REG_INTEN		0x0024
52 #define  REG_INTEN_TX		0x00000008
53 #define  REG_INTEN_RX		0x00000007
54 #define REG_INTSTSP		0x0028
55 #define  REG_INTSTS_TX		0x00000008
56 #define  REG_INTSTS_RX		0x00000004
57 #define REG_INTSTSC		0x002c
58 #define REG_AFP			0x004c
59 #define REG_INDAD0		0x0050
60 #define REG_INDAD1		0x0051
61 #define REG_INDAD2		0x0052
62 #define REG_INDAD3		0x0053
63 #define REG_INDAD4		0x0054
64 #define REG_INDAD5		0x0055
65 #define REG_GIINTMSK		0x0064
66 #define  REG_GIINTMSK_ENABLE	0x00008000
67 #define REG_BMCTL		0x0080
68 #define  REG_BMCTL_ENABLE_TX	0x00000100
69 #define  REG_BMCTL_ENABLE_RX	0x00000001
70 #define REG_BMSTS		0x0084
71 #define  REG_BMSTS_RX_ACTIVE	0x00000008
72 #define REG_RXDQBADD		0x0090
73 #define REG_RXDQBLEN		0x0094
74 #define REG_RXDCURADD		0x0098
75 #define REG_RXDENQ		0x009c
76 #define REG_RXSTSQBADD		0x00a0
77 #define REG_RXSTSQBLEN		0x00a4
78 #define REG_RXSTSQCURADD	0x00a8
79 #define REG_RXSTSENQ		0x00ac
80 #define REG_TXDQBADD		0x00b0
81 #define REG_TXDQBLEN		0x00b4
82 #define REG_TXDQCURADD		0x00b8
83 #define REG_TXDENQ		0x00bc
84 #define REG_TXSTSQBADD		0x00c0
85 #define REG_TXSTSQBLEN		0x00c4
86 #define REG_TXSTSQCURADD	0x00c8
87 #define REG_MAXFRMLEN		0x00e8
88 
89 struct ep93xx_rdesc
90 {
91 	u32	buf_addr;
92 	u32	rdesc1;
93 };
94 
95 #define RDESC1_NSOF		0x80000000
96 #define RDESC1_BUFFER_INDEX	0x7fff0000
97 #define RDESC1_BUFFER_LENGTH	0x0000ffff
98 
99 struct ep93xx_rstat
100 {
101 	u32	rstat0;
102 	u32	rstat1;
103 };
104 
105 #define RSTAT0_RFP		0x80000000
106 #define RSTAT0_RWE		0x40000000
107 #define RSTAT0_EOF		0x20000000
108 #define RSTAT0_EOB		0x10000000
109 #define RSTAT0_AM		0x00c00000
110 #define RSTAT0_RX_ERR		0x00200000
111 #define RSTAT0_OE		0x00100000
112 #define RSTAT0_FE		0x00080000
113 #define RSTAT0_RUNT		0x00040000
114 #define RSTAT0_EDATA		0x00020000
115 #define RSTAT0_CRCE		0x00010000
116 #define RSTAT0_CRCI		0x00008000
117 #define RSTAT0_HTI		0x00003f00
118 #define RSTAT1_RFP		0x80000000
119 #define RSTAT1_BUFFER_INDEX	0x7fff0000
120 #define RSTAT1_FRAME_LENGTH	0x0000ffff
121 
122 struct ep93xx_tdesc
123 {
124 	u32	buf_addr;
125 	u32	tdesc1;
126 };
127 
128 #define TDESC1_EOF		0x80000000
129 #define TDESC1_BUFFER_INDEX	0x7fff0000
130 #define TDESC1_BUFFER_ABORT	0x00008000
131 #define TDESC1_BUFFER_LENGTH	0x00000fff
132 
133 struct ep93xx_tstat
134 {
135 	u32	tstat0;
136 };
137 
138 #define TSTAT0_TXFP		0x80000000
139 #define TSTAT0_TXWE		0x40000000
140 #define TSTAT0_FA		0x20000000
141 #define TSTAT0_LCRS		0x10000000
142 #define TSTAT0_OW		0x04000000
143 #define TSTAT0_TXU		0x02000000
144 #define TSTAT0_ECOLL		0x01000000
145 #define TSTAT0_NCOLL		0x001f0000
146 #define TSTAT0_BUFFER_INDEX	0x00007fff
147 
148 struct ep93xx_descs
149 {
150 	struct ep93xx_rdesc	rdesc[RX_QUEUE_ENTRIES];
151 	struct ep93xx_tdesc	tdesc[TX_QUEUE_ENTRIES];
152 	struct ep93xx_rstat	rstat[RX_QUEUE_ENTRIES];
153 	struct ep93xx_tstat	tstat[TX_QUEUE_ENTRIES];
154 };
155 
156 struct ep93xx_priv
157 {
158 	struct resource		*res;
159 	void __iomem		*base_addr;
160 	int			irq;
161 
162 	struct ep93xx_descs	*descs;
163 	dma_addr_t		descs_dma_addr;
164 
165 	void			*rx_buf[RX_QUEUE_ENTRIES];
166 	void			*tx_buf[TX_QUEUE_ENTRIES];
167 
168 	spinlock_t		rx_lock;
169 	unsigned int		rx_pointer;
170 	unsigned int		tx_clean_pointer;
171 	unsigned int		tx_pointer;
172 	spinlock_t		tx_pending_lock;
173 	unsigned int		tx_pending;
174 
175 	struct net_device	*dev;
176 	struct napi_struct	napi;
177 
178 	struct mii_if_info	mii;
179 	u8			mdc_divisor;
180 };
181 
182 #define rdb(ep, off)		__raw_readb((ep)->base_addr + (off))
183 #define rdw(ep, off)		__raw_readw((ep)->base_addr + (off))
184 #define rdl(ep, off)		__raw_readl((ep)->base_addr + (off))
185 #define wrb(ep, off, val)	__raw_writeb((val), (ep)->base_addr + (off))
186 #define wrw(ep, off, val)	__raw_writew((val), (ep)->base_addr + (off))
187 #define wrl(ep, off, val)	__raw_writel((val), (ep)->base_addr + (off))
188 
189 static int ep93xx_mdio_read(struct net_device *dev, int phy_id, int reg)
190 {
191 	struct ep93xx_priv *ep = netdev_priv(dev);
192 	int data;
193 	int i;
194 
195 	wrl(ep, REG_MIICMD, REG_MIICMD_READ | (phy_id << 5) | reg);
196 
197 	for (i = 0; i < 10; i++) {
198 		if ((rdl(ep, REG_MIISTS) & REG_MIISTS_BUSY) == 0)
199 			break;
200 		msleep(1);
201 	}
202 
203 	if (i == 10) {
204 		pr_info("mdio read timed out\n");
205 		data = 0xffff;
206 	} else {
207 		data = rdl(ep, REG_MIIDATA);
208 	}
209 
210 	return data;
211 }
212 
213 static void ep93xx_mdio_write(struct net_device *dev, int phy_id, int reg, int data)
214 {
215 	struct ep93xx_priv *ep = netdev_priv(dev);
216 	int i;
217 
218 	wrl(ep, REG_MIIDATA, data);
219 	wrl(ep, REG_MIICMD, REG_MIICMD_WRITE | (phy_id << 5) | reg);
220 
221 	for (i = 0; i < 10; i++) {
222 		if ((rdl(ep, REG_MIISTS) & REG_MIISTS_BUSY) == 0)
223 			break;
224 		msleep(1);
225 	}
226 
227 	if (i == 10)
228 		pr_info("mdio write timed out\n");
229 }
230 
231 static int ep93xx_rx(struct net_device *dev, int processed, int budget)
232 {
233 	struct ep93xx_priv *ep = netdev_priv(dev);
234 
235 	while (processed < budget) {
236 		int entry;
237 		struct ep93xx_rstat *rstat;
238 		u32 rstat0;
239 		u32 rstat1;
240 		int length;
241 		struct sk_buff *skb;
242 
243 		entry = ep->rx_pointer;
244 		rstat = ep->descs->rstat + entry;
245 
246 		rstat0 = rstat->rstat0;
247 		rstat1 = rstat->rstat1;
248 		if (!(rstat0 & RSTAT0_RFP) || !(rstat1 & RSTAT1_RFP))
249 			break;
250 
251 		rstat->rstat0 = 0;
252 		rstat->rstat1 = 0;
253 
254 		if (!(rstat0 & RSTAT0_EOF))
255 			pr_crit("not end-of-frame %.8x %.8x\n", rstat0, rstat1);
256 		if (!(rstat0 & RSTAT0_EOB))
257 			pr_crit("not end-of-buffer %.8x %.8x\n", rstat0, rstat1);
258 		if ((rstat1 & RSTAT1_BUFFER_INDEX) >> 16 != entry)
259 			pr_crit("entry mismatch %.8x %.8x\n", rstat0, rstat1);
260 
261 		if (!(rstat0 & RSTAT0_RWE)) {
262 			dev->stats.rx_errors++;
263 			if (rstat0 & RSTAT0_OE)
264 				dev->stats.rx_fifo_errors++;
265 			if (rstat0 & RSTAT0_FE)
266 				dev->stats.rx_frame_errors++;
267 			if (rstat0 & (RSTAT0_RUNT | RSTAT0_EDATA))
268 				dev->stats.rx_length_errors++;
269 			if (rstat0 & RSTAT0_CRCE)
270 				dev->stats.rx_crc_errors++;
271 			goto err;
272 		}
273 
274 		length = rstat1 & RSTAT1_FRAME_LENGTH;
275 		if (length > MAX_PKT_SIZE) {
276 			pr_notice("invalid length %.8x %.8x\n", rstat0, rstat1);
277 			goto err;
278 		}
279 
280 		/* Strip FCS.  */
281 		if (rstat0 & RSTAT0_CRCI)
282 			length -= 4;
283 
284 		skb = netdev_alloc_skb(dev, length + 2);
285 		if (likely(skb != NULL)) {
286 			struct ep93xx_rdesc *rxd = &ep->descs->rdesc[entry];
287 			skb_reserve(skb, 2);
288 			dma_sync_single_for_cpu(dev->dev.parent, rxd->buf_addr,
289 						length, DMA_FROM_DEVICE);
290 			skb_copy_to_linear_data(skb, ep->rx_buf[entry], length);
291 			dma_sync_single_for_device(dev->dev.parent,
292 						   rxd->buf_addr, length,
293 						   DMA_FROM_DEVICE);
294 			skb_put(skb, length);
295 			skb->protocol = eth_type_trans(skb, dev);
296 
297 			netif_receive_skb(skb);
298 
299 			dev->stats.rx_packets++;
300 			dev->stats.rx_bytes += length;
301 		} else {
302 			dev->stats.rx_dropped++;
303 		}
304 
305 err:
306 		ep->rx_pointer = (entry + 1) & (RX_QUEUE_ENTRIES - 1);
307 		processed++;
308 	}
309 
310 	return processed;
311 }
312 
313 static int ep93xx_have_more_rx(struct ep93xx_priv *ep)
314 {
315 	struct ep93xx_rstat *rstat = ep->descs->rstat + ep->rx_pointer;
316 	return !!((rstat->rstat0 & RSTAT0_RFP) && (rstat->rstat1 & RSTAT1_RFP));
317 }
318 
319 static int ep93xx_poll(struct napi_struct *napi, int budget)
320 {
321 	struct ep93xx_priv *ep = container_of(napi, struct ep93xx_priv, napi);
322 	struct net_device *dev = ep->dev;
323 	int rx = 0;
324 
325 poll_some_more:
326 	rx = ep93xx_rx(dev, rx, budget);
327 	if (rx < budget) {
328 		int more = 0;
329 
330 		spin_lock_irq(&ep->rx_lock);
331 		__napi_complete(napi);
332 		wrl(ep, REG_INTEN, REG_INTEN_TX | REG_INTEN_RX);
333 		if (ep93xx_have_more_rx(ep)) {
334 			wrl(ep, REG_INTEN, REG_INTEN_TX);
335 			wrl(ep, REG_INTSTSP, REG_INTSTS_RX);
336 			more = 1;
337 		}
338 		spin_unlock_irq(&ep->rx_lock);
339 
340 		if (more && napi_reschedule(napi))
341 			goto poll_some_more;
342 	}
343 
344 	if (rx) {
345 		wrw(ep, REG_RXDENQ, rx);
346 		wrw(ep, REG_RXSTSENQ, rx);
347 	}
348 
349 	return rx;
350 }
351 
352 static int ep93xx_xmit(struct sk_buff *skb, struct net_device *dev)
353 {
354 	struct ep93xx_priv *ep = netdev_priv(dev);
355 	struct ep93xx_tdesc *txd;
356 	int entry;
357 
358 	if (unlikely(skb->len > MAX_PKT_SIZE)) {
359 		dev->stats.tx_dropped++;
360 		dev_kfree_skb(skb);
361 		return NETDEV_TX_OK;
362 	}
363 
364 	entry = ep->tx_pointer;
365 	ep->tx_pointer = (ep->tx_pointer + 1) & (TX_QUEUE_ENTRIES - 1);
366 
367 	txd = &ep->descs->tdesc[entry];
368 
369 	txd->tdesc1 = TDESC1_EOF | (entry << 16) | (skb->len & 0xfff);
370 	dma_sync_single_for_cpu(dev->dev.parent, txd->buf_addr, skb->len,
371 				DMA_TO_DEVICE);
372 	skb_copy_and_csum_dev(skb, ep->tx_buf[entry]);
373 	dma_sync_single_for_device(dev->dev.parent, txd->buf_addr, skb->len,
374 				   DMA_TO_DEVICE);
375 	dev_kfree_skb(skb);
376 
377 	spin_lock_irq(&ep->tx_pending_lock);
378 	ep->tx_pending++;
379 	if (ep->tx_pending == TX_QUEUE_ENTRIES)
380 		netif_stop_queue(dev);
381 	spin_unlock_irq(&ep->tx_pending_lock);
382 
383 	wrl(ep, REG_TXDENQ, 1);
384 
385 	return NETDEV_TX_OK;
386 }
387 
388 static void ep93xx_tx_complete(struct net_device *dev)
389 {
390 	struct ep93xx_priv *ep = netdev_priv(dev);
391 	int wake;
392 
393 	wake = 0;
394 
395 	spin_lock(&ep->tx_pending_lock);
396 	while (1) {
397 		int entry;
398 		struct ep93xx_tstat *tstat;
399 		u32 tstat0;
400 
401 		entry = ep->tx_clean_pointer;
402 		tstat = ep->descs->tstat + entry;
403 
404 		tstat0 = tstat->tstat0;
405 		if (!(tstat0 & TSTAT0_TXFP))
406 			break;
407 
408 		tstat->tstat0 = 0;
409 
410 		if (tstat0 & TSTAT0_FA)
411 			pr_crit("frame aborted %.8x\n", tstat0);
412 		if ((tstat0 & TSTAT0_BUFFER_INDEX) != entry)
413 			pr_crit("entry mismatch %.8x\n", tstat0);
414 
415 		if (tstat0 & TSTAT0_TXWE) {
416 			int length = ep->descs->tdesc[entry].tdesc1 & 0xfff;
417 
418 			dev->stats.tx_packets++;
419 			dev->stats.tx_bytes += length;
420 		} else {
421 			dev->stats.tx_errors++;
422 		}
423 
424 		if (tstat0 & TSTAT0_OW)
425 			dev->stats.tx_window_errors++;
426 		if (tstat0 & TSTAT0_TXU)
427 			dev->stats.tx_fifo_errors++;
428 		dev->stats.collisions += (tstat0 >> 16) & 0x1f;
429 
430 		ep->tx_clean_pointer = (entry + 1) & (TX_QUEUE_ENTRIES - 1);
431 		if (ep->tx_pending == TX_QUEUE_ENTRIES)
432 			wake = 1;
433 		ep->tx_pending--;
434 	}
435 	spin_unlock(&ep->tx_pending_lock);
436 
437 	if (wake)
438 		netif_wake_queue(dev);
439 }
440 
441 static irqreturn_t ep93xx_irq(int irq, void *dev_id)
442 {
443 	struct net_device *dev = dev_id;
444 	struct ep93xx_priv *ep = netdev_priv(dev);
445 	u32 status;
446 
447 	status = rdl(ep, REG_INTSTSC);
448 	if (status == 0)
449 		return IRQ_NONE;
450 
451 	if (status & REG_INTSTS_RX) {
452 		spin_lock(&ep->rx_lock);
453 		if (likely(napi_schedule_prep(&ep->napi))) {
454 			wrl(ep, REG_INTEN, REG_INTEN_TX);
455 			__napi_schedule(&ep->napi);
456 		}
457 		spin_unlock(&ep->rx_lock);
458 	}
459 
460 	if (status & REG_INTSTS_TX)
461 		ep93xx_tx_complete(dev);
462 
463 	return IRQ_HANDLED;
464 }
465 
466 static void ep93xx_free_buffers(struct ep93xx_priv *ep)
467 {
468 	struct device *dev = ep->dev->dev.parent;
469 	int i;
470 
471 	for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
472 		dma_addr_t d;
473 
474 		d = ep->descs->rdesc[i].buf_addr;
475 		if (d)
476 			dma_unmap_single(dev, d, PKT_BUF_SIZE, DMA_FROM_DEVICE);
477 
478 		kfree(ep->rx_buf[i]);
479 	}
480 
481 	for (i = 0; i < TX_QUEUE_ENTRIES; i++) {
482 		dma_addr_t d;
483 
484 		d = ep->descs->tdesc[i].buf_addr;
485 		if (d)
486 			dma_unmap_single(dev, d, PKT_BUF_SIZE, DMA_TO_DEVICE);
487 
488 		kfree(ep->tx_buf[i]);
489 	}
490 
491 	dma_free_coherent(dev, sizeof(struct ep93xx_descs), ep->descs,
492 							ep->descs_dma_addr);
493 }
494 
495 static int ep93xx_alloc_buffers(struct ep93xx_priv *ep)
496 {
497 	struct device *dev = ep->dev->dev.parent;
498 	int i;
499 
500 	ep->descs = dma_alloc_coherent(dev, sizeof(struct ep93xx_descs),
501 				&ep->descs_dma_addr, GFP_KERNEL);
502 	if (ep->descs == NULL)
503 		return 1;
504 
505 	for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
506 		void *buf;
507 		dma_addr_t d;
508 
509 		buf = kmalloc(PKT_BUF_SIZE, GFP_KERNEL);
510 		if (buf == NULL)
511 			goto err;
512 
513 		d = dma_map_single(dev, buf, PKT_BUF_SIZE, DMA_FROM_DEVICE);
514 		if (dma_mapping_error(dev, d)) {
515 			kfree(buf);
516 			goto err;
517 		}
518 
519 		ep->rx_buf[i] = buf;
520 		ep->descs->rdesc[i].buf_addr = d;
521 		ep->descs->rdesc[i].rdesc1 = (i << 16) | PKT_BUF_SIZE;
522 	}
523 
524 	for (i = 0; i < TX_QUEUE_ENTRIES; i++) {
525 		void *buf;
526 		dma_addr_t d;
527 
528 		buf = kmalloc(PKT_BUF_SIZE, GFP_KERNEL);
529 		if (buf == NULL)
530 			goto err;
531 
532 		d = dma_map_single(dev, buf, PKT_BUF_SIZE, DMA_TO_DEVICE);
533 		if (dma_mapping_error(dev, d)) {
534 			kfree(buf);
535 			goto err;
536 		}
537 
538 		ep->tx_buf[i] = buf;
539 		ep->descs->tdesc[i].buf_addr = d;
540 	}
541 
542 	return 0;
543 
544 err:
545 	ep93xx_free_buffers(ep);
546 	return 1;
547 }
548 
549 static int ep93xx_start_hw(struct net_device *dev)
550 {
551 	struct ep93xx_priv *ep = netdev_priv(dev);
552 	unsigned long addr;
553 	int i;
554 
555 	wrl(ep, REG_SELFCTL, REG_SELFCTL_RESET);
556 	for (i = 0; i < 10; i++) {
557 		if ((rdl(ep, REG_SELFCTL) & REG_SELFCTL_RESET) == 0)
558 			break;
559 		msleep(1);
560 	}
561 
562 	if (i == 10) {
563 		pr_crit("hw failed to reset\n");
564 		return 1;
565 	}
566 
567 	wrl(ep, REG_SELFCTL, ((ep->mdc_divisor - 1) << 9));
568 
569 	/* Does the PHY support preamble suppress?  */
570 	if ((ep93xx_mdio_read(dev, ep->mii.phy_id, MII_BMSR) & 0x0040) != 0)
571 		wrl(ep, REG_SELFCTL, ((ep->mdc_divisor - 1) << 9) | (1 << 8));
572 
573 	/* Receive descriptor ring.  */
574 	addr = ep->descs_dma_addr + offsetof(struct ep93xx_descs, rdesc);
575 	wrl(ep, REG_RXDQBADD, addr);
576 	wrl(ep, REG_RXDCURADD, addr);
577 	wrw(ep, REG_RXDQBLEN, RX_QUEUE_ENTRIES * sizeof(struct ep93xx_rdesc));
578 
579 	/* Receive status ring.  */
580 	addr = ep->descs_dma_addr + offsetof(struct ep93xx_descs, rstat);
581 	wrl(ep, REG_RXSTSQBADD, addr);
582 	wrl(ep, REG_RXSTSQCURADD, addr);
583 	wrw(ep, REG_RXSTSQBLEN, RX_QUEUE_ENTRIES * sizeof(struct ep93xx_rstat));
584 
585 	/* Transmit descriptor ring.  */
586 	addr = ep->descs_dma_addr + offsetof(struct ep93xx_descs, tdesc);
587 	wrl(ep, REG_TXDQBADD, addr);
588 	wrl(ep, REG_TXDQCURADD, addr);
589 	wrw(ep, REG_TXDQBLEN, TX_QUEUE_ENTRIES * sizeof(struct ep93xx_tdesc));
590 
591 	/* Transmit status ring.  */
592 	addr = ep->descs_dma_addr + offsetof(struct ep93xx_descs, tstat);
593 	wrl(ep, REG_TXSTSQBADD, addr);
594 	wrl(ep, REG_TXSTSQCURADD, addr);
595 	wrw(ep, REG_TXSTSQBLEN, TX_QUEUE_ENTRIES * sizeof(struct ep93xx_tstat));
596 
597 	wrl(ep, REG_BMCTL, REG_BMCTL_ENABLE_TX | REG_BMCTL_ENABLE_RX);
598 	wrl(ep, REG_INTEN, REG_INTEN_TX | REG_INTEN_RX);
599 	wrl(ep, REG_GIINTMSK, 0);
600 
601 	for (i = 0; i < 10; i++) {
602 		if ((rdl(ep, REG_BMSTS) & REG_BMSTS_RX_ACTIVE) != 0)
603 			break;
604 		msleep(1);
605 	}
606 
607 	if (i == 10) {
608 		pr_crit("hw failed to start\n");
609 		return 1;
610 	}
611 
612 	wrl(ep, REG_RXDENQ, RX_QUEUE_ENTRIES);
613 	wrl(ep, REG_RXSTSENQ, RX_QUEUE_ENTRIES);
614 
615 	wrb(ep, REG_INDAD0, dev->dev_addr[0]);
616 	wrb(ep, REG_INDAD1, dev->dev_addr[1]);
617 	wrb(ep, REG_INDAD2, dev->dev_addr[2]);
618 	wrb(ep, REG_INDAD3, dev->dev_addr[3]);
619 	wrb(ep, REG_INDAD4, dev->dev_addr[4]);
620 	wrb(ep, REG_INDAD5, dev->dev_addr[5]);
621 	wrl(ep, REG_AFP, 0);
622 
623 	wrl(ep, REG_MAXFRMLEN, (MAX_PKT_SIZE << 16) | MAX_PKT_SIZE);
624 
625 	wrl(ep, REG_RXCTL, REG_RXCTL_DEFAULT);
626 	wrl(ep, REG_TXCTL, REG_TXCTL_ENABLE);
627 
628 	return 0;
629 }
630 
631 static void ep93xx_stop_hw(struct net_device *dev)
632 {
633 	struct ep93xx_priv *ep = netdev_priv(dev);
634 	int i;
635 
636 	wrl(ep, REG_SELFCTL, REG_SELFCTL_RESET);
637 	for (i = 0; i < 10; i++) {
638 		if ((rdl(ep, REG_SELFCTL) & REG_SELFCTL_RESET) == 0)
639 			break;
640 		msleep(1);
641 	}
642 
643 	if (i == 10)
644 		pr_crit("hw failed to reset\n");
645 }
646 
647 static int ep93xx_open(struct net_device *dev)
648 {
649 	struct ep93xx_priv *ep = netdev_priv(dev);
650 	int err;
651 
652 	if (ep93xx_alloc_buffers(ep))
653 		return -ENOMEM;
654 
655 	napi_enable(&ep->napi);
656 
657 	if (ep93xx_start_hw(dev)) {
658 		napi_disable(&ep->napi);
659 		ep93xx_free_buffers(ep);
660 		return -EIO;
661 	}
662 
663 	spin_lock_init(&ep->rx_lock);
664 	ep->rx_pointer = 0;
665 	ep->tx_clean_pointer = 0;
666 	ep->tx_pointer = 0;
667 	spin_lock_init(&ep->tx_pending_lock);
668 	ep->tx_pending = 0;
669 
670 	err = request_irq(ep->irq, ep93xx_irq, IRQF_SHARED, dev->name, dev);
671 	if (err) {
672 		napi_disable(&ep->napi);
673 		ep93xx_stop_hw(dev);
674 		ep93xx_free_buffers(ep);
675 		return err;
676 	}
677 
678 	wrl(ep, REG_GIINTMSK, REG_GIINTMSK_ENABLE);
679 
680 	netif_start_queue(dev);
681 
682 	return 0;
683 }
684 
685 static int ep93xx_close(struct net_device *dev)
686 {
687 	struct ep93xx_priv *ep = netdev_priv(dev);
688 
689 	napi_disable(&ep->napi);
690 	netif_stop_queue(dev);
691 
692 	wrl(ep, REG_GIINTMSK, 0);
693 	free_irq(ep->irq, dev);
694 	ep93xx_stop_hw(dev);
695 	ep93xx_free_buffers(ep);
696 
697 	return 0;
698 }
699 
700 static int ep93xx_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
701 {
702 	struct ep93xx_priv *ep = netdev_priv(dev);
703 	struct mii_ioctl_data *data = if_mii(ifr);
704 
705 	return generic_mii_ioctl(&ep->mii, data, cmd, NULL);
706 }
707 
708 static void ep93xx_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
709 {
710 	strlcpy(info->driver, DRV_MODULE_NAME, sizeof(info->driver));
711 	strlcpy(info->version, DRV_MODULE_VERSION, sizeof(info->version));
712 }
713 
714 static int ep93xx_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
715 {
716 	struct ep93xx_priv *ep = netdev_priv(dev);
717 	return mii_ethtool_gset(&ep->mii, cmd);
718 }
719 
720 static int ep93xx_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
721 {
722 	struct ep93xx_priv *ep = netdev_priv(dev);
723 	return mii_ethtool_sset(&ep->mii, cmd);
724 }
725 
726 static int ep93xx_nway_reset(struct net_device *dev)
727 {
728 	struct ep93xx_priv *ep = netdev_priv(dev);
729 	return mii_nway_restart(&ep->mii);
730 }
731 
732 static u32 ep93xx_get_link(struct net_device *dev)
733 {
734 	struct ep93xx_priv *ep = netdev_priv(dev);
735 	return mii_link_ok(&ep->mii);
736 }
737 
738 static const struct ethtool_ops ep93xx_ethtool_ops = {
739 	.get_drvinfo		= ep93xx_get_drvinfo,
740 	.get_settings		= ep93xx_get_settings,
741 	.set_settings		= ep93xx_set_settings,
742 	.nway_reset		= ep93xx_nway_reset,
743 	.get_link		= ep93xx_get_link,
744 };
745 
746 static const struct net_device_ops ep93xx_netdev_ops = {
747 	.ndo_open		= ep93xx_open,
748 	.ndo_stop		= ep93xx_close,
749 	.ndo_start_xmit		= ep93xx_xmit,
750 	.ndo_do_ioctl		= ep93xx_ioctl,
751 	.ndo_validate_addr	= eth_validate_addr,
752 	.ndo_change_mtu		= eth_change_mtu,
753 	.ndo_set_mac_address	= eth_mac_addr,
754 };
755 
756 static struct net_device *ep93xx_dev_alloc(struct ep93xx_eth_data *data)
757 {
758 	struct net_device *dev;
759 
760 	dev = alloc_etherdev(sizeof(struct ep93xx_priv));
761 	if (dev == NULL)
762 		return NULL;
763 
764 	memcpy(dev->dev_addr, data->dev_addr, ETH_ALEN);
765 
766 	dev->ethtool_ops = &ep93xx_ethtool_ops;
767 	dev->netdev_ops = &ep93xx_netdev_ops;
768 
769 	dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM;
770 
771 	return dev;
772 }
773 
774 
775 static int ep93xx_eth_remove(struct platform_device *pdev)
776 {
777 	struct net_device *dev;
778 	struct ep93xx_priv *ep;
779 
780 	dev = platform_get_drvdata(pdev);
781 	if (dev == NULL)
782 		return 0;
783 
784 	ep = netdev_priv(dev);
785 
786 	/* @@@ Force down.  */
787 	unregister_netdev(dev);
788 	ep93xx_free_buffers(ep);
789 
790 	if (ep->base_addr != NULL)
791 		iounmap(ep->base_addr);
792 
793 	if (ep->res != NULL) {
794 		release_resource(ep->res);
795 		kfree(ep->res);
796 	}
797 
798 	free_netdev(dev);
799 
800 	return 0;
801 }
802 
803 static int ep93xx_eth_probe(struct platform_device *pdev)
804 {
805 	struct ep93xx_eth_data *data;
806 	struct net_device *dev;
807 	struct ep93xx_priv *ep;
808 	struct resource *mem;
809 	int irq;
810 	int err;
811 
812 	if (pdev == NULL)
813 		return -ENODEV;
814 	data = dev_get_platdata(&pdev->dev);
815 
816 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
817 	irq = platform_get_irq(pdev, 0);
818 	if (!mem || irq < 0)
819 		return -ENXIO;
820 
821 	dev = ep93xx_dev_alloc(data);
822 	if (dev == NULL) {
823 		err = -ENOMEM;
824 		goto err_out;
825 	}
826 	ep = netdev_priv(dev);
827 	ep->dev = dev;
828 	SET_NETDEV_DEV(dev, &pdev->dev);
829 	netif_napi_add(dev, &ep->napi, ep93xx_poll, 64);
830 
831 	platform_set_drvdata(pdev, dev);
832 
833 	ep->res = request_mem_region(mem->start, resource_size(mem),
834 				     dev_name(&pdev->dev));
835 	if (ep->res == NULL) {
836 		dev_err(&pdev->dev, "Could not reserve memory region\n");
837 		err = -ENOMEM;
838 		goto err_out;
839 	}
840 
841 	ep->base_addr = ioremap(mem->start, resource_size(mem));
842 	if (ep->base_addr == NULL) {
843 		dev_err(&pdev->dev, "Failed to ioremap ethernet registers\n");
844 		err = -EIO;
845 		goto err_out;
846 	}
847 	ep->irq = irq;
848 
849 	ep->mii.phy_id = data->phy_id;
850 	ep->mii.phy_id_mask = 0x1f;
851 	ep->mii.reg_num_mask = 0x1f;
852 	ep->mii.dev = dev;
853 	ep->mii.mdio_read = ep93xx_mdio_read;
854 	ep->mii.mdio_write = ep93xx_mdio_write;
855 	ep->mdc_divisor = 40;	/* Max HCLK 100 MHz, min MDIO clk 2.5 MHz.  */
856 
857 	if (is_zero_ether_addr(dev->dev_addr))
858 		eth_hw_addr_random(dev);
859 
860 	err = register_netdev(dev);
861 	if (err) {
862 		dev_err(&pdev->dev, "Failed to register netdev\n");
863 		goto err_out;
864 	}
865 
866 	printk(KERN_INFO "%s: ep93xx on-chip ethernet, IRQ %d, %pM\n",
867 			dev->name, ep->irq, dev->dev_addr);
868 
869 	return 0;
870 
871 err_out:
872 	ep93xx_eth_remove(pdev);
873 	return err;
874 }
875 
876 
877 static struct platform_driver ep93xx_eth_driver = {
878 	.probe		= ep93xx_eth_probe,
879 	.remove		= ep93xx_eth_remove,
880 	.driver		= {
881 		.name	= "ep93xx-eth",
882 	},
883 };
884 
885 module_platform_driver(ep93xx_eth_driver);
886 
887 MODULE_LICENSE("GPL");
888 MODULE_ALIAS("platform:ep93xx-eth");
889