xref: /linux/drivers/net/ethernet/cirrus/ep93xx_eth.c (revision ae22a94997b8a03dcb3c922857c203246711f9d4)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * EP93xx ethernet network device driver
4  * Copyright (C) 2006 Lennert Buytenhek <buytenh@wantstofly.org>
5  * Dedicated to Marija Kulikova.
6  */
7 
8 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
9 
10 #include <linux/dma-mapping.h>
11 #include <linux/module.h>
12 #include <linux/kernel.h>
13 #include <linux/netdevice.h>
14 #include <linux/mii.h>
15 #include <linux/etherdevice.h>
16 #include <linux/ethtool.h>
17 #include <linux/interrupt.h>
18 #include <linux/moduleparam.h>
19 #include <linux/platform_device.h>
20 #include <linux/delay.h>
21 #include <linux/io.h>
22 #include <linux/slab.h>
23 
24 #include <linux/platform_data/eth-ep93xx.h>
25 
26 #define DRV_MODULE_NAME		"ep93xx-eth"
27 
28 #define RX_QUEUE_ENTRIES	64
29 #define TX_QUEUE_ENTRIES	8
30 
31 #define MAX_PKT_SIZE		2044
32 #define PKT_BUF_SIZE		2048
33 
34 #define REG_RXCTL		0x0000
35 #define  REG_RXCTL_DEFAULT	0x00073800
36 #define REG_TXCTL		0x0004
37 #define  REG_TXCTL_ENABLE	0x00000001
38 #define REG_MIICMD		0x0010
39 #define  REG_MIICMD_READ	0x00008000
40 #define  REG_MIICMD_WRITE	0x00004000
41 #define REG_MIIDATA		0x0014
42 #define REG_MIISTS		0x0018
43 #define  REG_MIISTS_BUSY	0x00000001
44 #define REG_SELFCTL		0x0020
45 #define  REG_SELFCTL_RESET	0x00000001
46 #define REG_INTEN		0x0024
47 #define  REG_INTEN_TX		0x00000008
48 #define  REG_INTEN_RX		0x00000007
49 #define REG_INTSTSP		0x0028
50 #define  REG_INTSTS_TX		0x00000008
51 #define  REG_INTSTS_RX		0x00000004
52 #define REG_INTSTSC		0x002c
53 #define REG_AFP			0x004c
54 #define REG_INDAD0		0x0050
55 #define REG_INDAD1		0x0051
56 #define REG_INDAD2		0x0052
57 #define REG_INDAD3		0x0053
58 #define REG_INDAD4		0x0054
59 #define REG_INDAD5		0x0055
60 #define REG_GIINTMSK		0x0064
61 #define  REG_GIINTMSK_ENABLE	0x00008000
62 #define REG_BMCTL		0x0080
63 #define  REG_BMCTL_ENABLE_TX	0x00000100
64 #define  REG_BMCTL_ENABLE_RX	0x00000001
65 #define REG_BMSTS		0x0084
66 #define  REG_BMSTS_RX_ACTIVE	0x00000008
67 #define REG_RXDQBADD		0x0090
68 #define REG_RXDQBLEN		0x0094
69 #define REG_RXDCURADD		0x0098
70 #define REG_RXDENQ		0x009c
71 #define REG_RXSTSQBADD		0x00a0
72 #define REG_RXSTSQBLEN		0x00a4
73 #define REG_RXSTSQCURADD	0x00a8
74 #define REG_RXSTSENQ		0x00ac
75 #define REG_TXDQBADD		0x00b0
76 #define REG_TXDQBLEN		0x00b4
77 #define REG_TXDQCURADD		0x00b8
78 #define REG_TXDENQ		0x00bc
79 #define REG_TXSTSQBADD		0x00c0
80 #define REG_TXSTSQBLEN		0x00c4
81 #define REG_TXSTSQCURADD	0x00c8
82 #define REG_MAXFRMLEN		0x00e8
83 
84 struct ep93xx_rdesc
85 {
86 	u32	buf_addr;
87 	u32	rdesc1;
88 };
89 
90 #define RDESC1_NSOF		0x80000000
91 #define RDESC1_BUFFER_INDEX	0x7fff0000
92 #define RDESC1_BUFFER_LENGTH	0x0000ffff
93 
94 struct ep93xx_rstat
95 {
96 	u32	rstat0;
97 	u32	rstat1;
98 };
99 
100 #define RSTAT0_RFP		0x80000000
101 #define RSTAT0_RWE		0x40000000
102 #define RSTAT0_EOF		0x20000000
103 #define RSTAT0_EOB		0x10000000
104 #define RSTAT0_AM		0x00c00000
105 #define RSTAT0_RX_ERR		0x00200000
106 #define RSTAT0_OE		0x00100000
107 #define RSTAT0_FE		0x00080000
108 #define RSTAT0_RUNT		0x00040000
109 #define RSTAT0_EDATA		0x00020000
110 #define RSTAT0_CRCE		0x00010000
111 #define RSTAT0_CRCI		0x00008000
112 #define RSTAT0_HTI		0x00003f00
113 #define RSTAT1_RFP		0x80000000
114 #define RSTAT1_BUFFER_INDEX	0x7fff0000
115 #define RSTAT1_FRAME_LENGTH	0x0000ffff
116 
117 struct ep93xx_tdesc
118 {
119 	u32	buf_addr;
120 	u32	tdesc1;
121 };
122 
123 #define TDESC1_EOF		0x80000000
124 #define TDESC1_BUFFER_INDEX	0x7fff0000
125 #define TDESC1_BUFFER_ABORT	0x00008000
126 #define TDESC1_BUFFER_LENGTH	0x00000fff
127 
128 struct ep93xx_tstat
129 {
130 	u32	tstat0;
131 };
132 
133 #define TSTAT0_TXFP		0x80000000
134 #define TSTAT0_TXWE		0x40000000
135 #define TSTAT0_FA		0x20000000
136 #define TSTAT0_LCRS		0x10000000
137 #define TSTAT0_OW		0x04000000
138 #define TSTAT0_TXU		0x02000000
139 #define TSTAT0_ECOLL		0x01000000
140 #define TSTAT0_NCOLL		0x001f0000
141 #define TSTAT0_BUFFER_INDEX	0x00007fff
142 
143 struct ep93xx_descs
144 {
145 	struct ep93xx_rdesc	rdesc[RX_QUEUE_ENTRIES];
146 	struct ep93xx_tdesc	tdesc[TX_QUEUE_ENTRIES];
147 	struct ep93xx_rstat	rstat[RX_QUEUE_ENTRIES];
148 	struct ep93xx_tstat	tstat[TX_QUEUE_ENTRIES];
149 };
150 
151 struct ep93xx_priv
152 {
153 	struct resource		*res;
154 	void __iomem		*base_addr;
155 	int			irq;
156 
157 	struct ep93xx_descs	*descs;
158 	dma_addr_t		descs_dma_addr;
159 
160 	void			*rx_buf[RX_QUEUE_ENTRIES];
161 	void			*tx_buf[TX_QUEUE_ENTRIES];
162 
163 	spinlock_t		rx_lock;
164 	unsigned int		rx_pointer;
165 	unsigned int		tx_clean_pointer;
166 	unsigned int		tx_pointer;
167 	spinlock_t		tx_pending_lock;
168 	unsigned int		tx_pending;
169 
170 	struct net_device	*dev;
171 	struct napi_struct	napi;
172 
173 	struct mii_if_info	mii;
174 	u8			mdc_divisor;
175 };
176 
177 #define rdb(ep, off)		__raw_readb((ep)->base_addr + (off))
178 #define rdw(ep, off)		__raw_readw((ep)->base_addr + (off))
179 #define rdl(ep, off)		__raw_readl((ep)->base_addr + (off))
180 #define wrb(ep, off, val)	__raw_writeb((val), (ep)->base_addr + (off))
181 #define wrw(ep, off, val)	__raw_writew((val), (ep)->base_addr + (off))
182 #define wrl(ep, off, val)	__raw_writel((val), (ep)->base_addr + (off))
183 
184 static int ep93xx_mdio_read(struct net_device *dev, int phy_id, int reg)
185 {
186 	struct ep93xx_priv *ep = netdev_priv(dev);
187 	int data;
188 	int i;
189 
190 	wrl(ep, REG_MIICMD, REG_MIICMD_READ | (phy_id << 5) | reg);
191 
192 	for (i = 0; i < 10; i++) {
193 		if ((rdl(ep, REG_MIISTS) & REG_MIISTS_BUSY) == 0)
194 			break;
195 		msleep(1);
196 	}
197 
198 	if (i == 10) {
199 		pr_info("mdio read timed out\n");
200 		data = 0xffff;
201 	} else {
202 		data = rdl(ep, REG_MIIDATA);
203 	}
204 
205 	return data;
206 }
207 
208 static void ep93xx_mdio_write(struct net_device *dev, int phy_id, int reg, int data)
209 {
210 	struct ep93xx_priv *ep = netdev_priv(dev);
211 	int i;
212 
213 	wrl(ep, REG_MIIDATA, data);
214 	wrl(ep, REG_MIICMD, REG_MIICMD_WRITE | (phy_id << 5) | reg);
215 
216 	for (i = 0; i < 10; i++) {
217 		if ((rdl(ep, REG_MIISTS) & REG_MIISTS_BUSY) == 0)
218 			break;
219 		msleep(1);
220 	}
221 
222 	if (i == 10)
223 		pr_info("mdio write timed out\n");
224 }
225 
226 static int ep93xx_rx(struct net_device *dev, int budget)
227 {
228 	struct ep93xx_priv *ep = netdev_priv(dev);
229 	int processed = 0;
230 
231 	while (processed < budget) {
232 		int entry;
233 		struct ep93xx_rstat *rstat;
234 		u32 rstat0;
235 		u32 rstat1;
236 		int length;
237 		struct sk_buff *skb;
238 
239 		entry = ep->rx_pointer;
240 		rstat = ep->descs->rstat + entry;
241 
242 		rstat0 = rstat->rstat0;
243 		rstat1 = rstat->rstat1;
244 		if (!(rstat0 & RSTAT0_RFP) || !(rstat1 & RSTAT1_RFP))
245 			break;
246 
247 		rstat->rstat0 = 0;
248 		rstat->rstat1 = 0;
249 
250 		if (!(rstat0 & RSTAT0_EOF))
251 			pr_crit("not end-of-frame %.8x %.8x\n", rstat0, rstat1);
252 		if (!(rstat0 & RSTAT0_EOB))
253 			pr_crit("not end-of-buffer %.8x %.8x\n", rstat0, rstat1);
254 		if ((rstat1 & RSTAT1_BUFFER_INDEX) >> 16 != entry)
255 			pr_crit("entry mismatch %.8x %.8x\n", rstat0, rstat1);
256 
257 		if (!(rstat0 & RSTAT0_RWE)) {
258 			dev->stats.rx_errors++;
259 			if (rstat0 & RSTAT0_OE)
260 				dev->stats.rx_fifo_errors++;
261 			if (rstat0 & RSTAT0_FE)
262 				dev->stats.rx_frame_errors++;
263 			if (rstat0 & (RSTAT0_RUNT | RSTAT0_EDATA))
264 				dev->stats.rx_length_errors++;
265 			if (rstat0 & RSTAT0_CRCE)
266 				dev->stats.rx_crc_errors++;
267 			goto err;
268 		}
269 
270 		length = rstat1 & RSTAT1_FRAME_LENGTH;
271 		if (length > MAX_PKT_SIZE) {
272 			pr_notice("invalid length %.8x %.8x\n", rstat0, rstat1);
273 			goto err;
274 		}
275 
276 		/* Strip FCS.  */
277 		if (rstat0 & RSTAT0_CRCI)
278 			length -= 4;
279 
280 		skb = netdev_alloc_skb(dev, length + 2);
281 		if (likely(skb != NULL)) {
282 			struct ep93xx_rdesc *rxd = &ep->descs->rdesc[entry];
283 			skb_reserve(skb, 2);
284 			dma_sync_single_for_cpu(dev->dev.parent, rxd->buf_addr,
285 						length, DMA_FROM_DEVICE);
286 			skb_copy_to_linear_data(skb, ep->rx_buf[entry], length);
287 			dma_sync_single_for_device(dev->dev.parent,
288 						   rxd->buf_addr, length,
289 						   DMA_FROM_DEVICE);
290 			skb_put(skb, length);
291 			skb->protocol = eth_type_trans(skb, dev);
292 
293 			napi_gro_receive(&ep->napi, skb);
294 
295 			dev->stats.rx_packets++;
296 			dev->stats.rx_bytes += length;
297 		} else {
298 			dev->stats.rx_dropped++;
299 		}
300 
301 err:
302 		ep->rx_pointer = (entry + 1) & (RX_QUEUE_ENTRIES - 1);
303 		processed++;
304 	}
305 
306 	return processed;
307 }
308 
309 static int ep93xx_poll(struct napi_struct *napi, int budget)
310 {
311 	struct ep93xx_priv *ep = container_of(napi, struct ep93xx_priv, napi);
312 	struct net_device *dev = ep->dev;
313 	int rx;
314 
315 	rx = ep93xx_rx(dev, budget);
316 	if (rx < budget && napi_complete_done(napi, rx)) {
317 		spin_lock_irq(&ep->rx_lock);
318 		wrl(ep, REG_INTEN, REG_INTEN_TX | REG_INTEN_RX);
319 		spin_unlock_irq(&ep->rx_lock);
320 	}
321 
322 	if (rx) {
323 		wrw(ep, REG_RXDENQ, rx);
324 		wrw(ep, REG_RXSTSENQ, rx);
325 	}
326 
327 	return rx;
328 }
329 
330 static netdev_tx_t ep93xx_xmit(struct sk_buff *skb, struct net_device *dev)
331 {
332 	struct ep93xx_priv *ep = netdev_priv(dev);
333 	struct ep93xx_tdesc *txd;
334 	int entry;
335 
336 	if (unlikely(skb->len > MAX_PKT_SIZE)) {
337 		dev->stats.tx_dropped++;
338 		dev_kfree_skb(skb);
339 		return NETDEV_TX_OK;
340 	}
341 
342 	entry = ep->tx_pointer;
343 	ep->tx_pointer = (ep->tx_pointer + 1) & (TX_QUEUE_ENTRIES - 1);
344 
345 	txd = &ep->descs->tdesc[entry];
346 
347 	txd->tdesc1 = TDESC1_EOF | (entry << 16) | (skb->len & 0xfff);
348 	dma_sync_single_for_cpu(dev->dev.parent, txd->buf_addr, skb->len,
349 				DMA_TO_DEVICE);
350 	skb_copy_and_csum_dev(skb, ep->tx_buf[entry]);
351 	dma_sync_single_for_device(dev->dev.parent, txd->buf_addr, skb->len,
352 				   DMA_TO_DEVICE);
353 	dev_kfree_skb(skb);
354 
355 	spin_lock_irq(&ep->tx_pending_lock);
356 	ep->tx_pending++;
357 	if (ep->tx_pending == TX_QUEUE_ENTRIES)
358 		netif_stop_queue(dev);
359 	spin_unlock_irq(&ep->tx_pending_lock);
360 
361 	wrl(ep, REG_TXDENQ, 1);
362 
363 	return NETDEV_TX_OK;
364 }
365 
366 static void ep93xx_tx_complete(struct net_device *dev)
367 {
368 	struct ep93xx_priv *ep = netdev_priv(dev);
369 	int wake;
370 
371 	wake = 0;
372 
373 	spin_lock(&ep->tx_pending_lock);
374 	while (1) {
375 		int entry;
376 		struct ep93xx_tstat *tstat;
377 		u32 tstat0;
378 
379 		entry = ep->tx_clean_pointer;
380 		tstat = ep->descs->tstat + entry;
381 
382 		tstat0 = tstat->tstat0;
383 		if (!(tstat0 & TSTAT0_TXFP))
384 			break;
385 
386 		tstat->tstat0 = 0;
387 
388 		if (tstat0 & TSTAT0_FA)
389 			pr_crit("frame aborted %.8x\n", tstat0);
390 		if ((tstat0 & TSTAT0_BUFFER_INDEX) != entry)
391 			pr_crit("entry mismatch %.8x\n", tstat0);
392 
393 		if (tstat0 & TSTAT0_TXWE) {
394 			int length = ep->descs->tdesc[entry].tdesc1 & 0xfff;
395 
396 			dev->stats.tx_packets++;
397 			dev->stats.tx_bytes += length;
398 		} else {
399 			dev->stats.tx_errors++;
400 		}
401 
402 		if (tstat0 & TSTAT0_OW)
403 			dev->stats.tx_window_errors++;
404 		if (tstat0 & TSTAT0_TXU)
405 			dev->stats.tx_fifo_errors++;
406 		dev->stats.collisions += (tstat0 >> 16) & 0x1f;
407 
408 		ep->tx_clean_pointer = (entry + 1) & (TX_QUEUE_ENTRIES - 1);
409 		if (ep->tx_pending == TX_QUEUE_ENTRIES)
410 			wake = 1;
411 		ep->tx_pending--;
412 	}
413 	spin_unlock(&ep->tx_pending_lock);
414 
415 	if (wake)
416 		netif_wake_queue(dev);
417 }
418 
419 static irqreturn_t ep93xx_irq(int irq, void *dev_id)
420 {
421 	struct net_device *dev = dev_id;
422 	struct ep93xx_priv *ep = netdev_priv(dev);
423 	u32 status;
424 
425 	status = rdl(ep, REG_INTSTSC);
426 	if (status == 0)
427 		return IRQ_NONE;
428 
429 	if (status & REG_INTSTS_RX) {
430 		spin_lock(&ep->rx_lock);
431 		if (likely(napi_schedule_prep(&ep->napi))) {
432 			wrl(ep, REG_INTEN, REG_INTEN_TX);
433 			__napi_schedule(&ep->napi);
434 		}
435 		spin_unlock(&ep->rx_lock);
436 	}
437 
438 	if (status & REG_INTSTS_TX)
439 		ep93xx_tx_complete(dev);
440 
441 	return IRQ_HANDLED;
442 }
443 
444 static void ep93xx_free_buffers(struct ep93xx_priv *ep)
445 {
446 	struct device *dev = ep->dev->dev.parent;
447 	int i;
448 
449 	if (!ep->descs)
450 		return;
451 
452 	for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
453 		dma_addr_t d;
454 
455 		d = ep->descs->rdesc[i].buf_addr;
456 		if (d)
457 			dma_unmap_single(dev, d, PKT_BUF_SIZE, DMA_FROM_DEVICE);
458 
459 		kfree(ep->rx_buf[i]);
460 	}
461 
462 	for (i = 0; i < TX_QUEUE_ENTRIES; i++) {
463 		dma_addr_t d;
464 
465 		d = ep->descs->tdesc[i].buf_addr;
466 		if (d)
467 			dma_unmap_single(dev, d, PKT_BUF_SIZE, DMA_TO_DEVICE);
468 
469 		kfree(ep->tx_buf[i]);
470 	}
471 
472 	dma_free_coherent(dev, sizeof(struct ep93xx_descs), ep->descs,
473 							ep->descs_dma_addr);
474 	ep->descs = NULL;
475 }
476 
477 static int ep93xx_alloc_buffers(struct ep93xx_priv *ep)
478 {
479 	struct device *dev = ep->dev->dev.parent;
480 	int i;
481 
482 	ep->descs = dma_alloc_coherent(dev, sizeof(struct ep93xx_descs),
483 				&ep->descs_dma_addr, GFP_KERNEL);
484 	if (ep->descs == NULL)
485 		return 1;
486 
487 	for (i = 0; i < RX_QUEUE_ENTRIES; i++) {
488 		void *buf;
489 		dma_addr_t d;
490 
491 		buf = kmalloc(PKT_BUF_SIZE, GFP_KERNEL);
492 		if (buf == NULL)
493 			goto err;
494 
495 		d = dma_map_single(dev, buf, PKT_BUF_SIZE, DMA_FROM_DEVICE);
496 		if (dma_mapping_error(dev, d)) {
497 			kfree(buf);
498 			goto err;
499 		}
500 
501 		ep->rx_buf[i] = buf;
502 		ep->descs->rdesc[i].buf_addr = d;
503 		ep->descs->rdesc[i].rdesc1 = (i << 16) | PKT_BUF_SIZE;
504 	}
505 
506 	for (i = 0; i < TX_QUEUE_ENTRIES; i++) {
507 		void *buf;
508 		dma_addr_t d;
509 
510 		buf = kmalloc(PKT_BUF_SIZE, GFP_KERNEL);
511 		if (buf == NULL)
512 			goto err;
513 
514 		d = dma_map_single(dev, buf, PKT_BUF_SIZE, DMA_TO_DEVICE);
515 		if (dma_mapping_error(dev, d)) {
516 			kfree(buf);
517 			goto err;
518 		}
519 
520 		ep->tx_buf[i] = buf;
521 		ep->descs->tdesc[i].buf_addr = d;
522 	}
523 
524 	return 0;
525 
526 err:
527 	ep93xx_free_buffers(ep);
528 	return 1;
529 }
530 
531 static int ep93xx_start_hw(struct net_device *dev)
532 {
533 	struct ep93xx_priv *ep = netdev_priv(dev);
534 	unsigned long addr;
535 	int i;
536 
537 	wrl(ep, REG_SELFCTL, REG_SELFCTL_RESET);
538 	for (i = 0; i < 10; i++) {
539 		if ((rdl(ep, REG_SELFCTL) & REG_SELFCTL_RESET) == 0)
540 			break;
541 		msleep(1);
542 	}
543 
544 	if (i == 10) {
545 		pr_crit("hw failed to reset\n");
546 		return 1;
547 	}
548 
549 	wrl(ep, REG_SELFCTL, ((ep->mdc_divisor - 1) << 9));
550 
551 	/* Does the PHY support preamble suppress?  */
552 	if ((ep93xx_mdio_read(dev, ep->mii.phy_id, MII_BMSR) & 0x0040) != 0)
553 		wrl(ep, REG_SELFCTL, ((ep->mdc_divisor - 1) << 9) | (1 << 8));
554 
555 	/* Receive descriptor ring.  */
556 	addr = ep->descs_dma_addr + offsetof(struct ep93xx_descs, rdesc);
557 	wrl(ep, REG_RXDQBADD, addr);
558 	wrl(ep, REG_RXDCURADD, addr);
559 	wrw(ep, REG_RXDQBLEN, RX_QUEUE_ENTRIES * sizeof(struct ep93xx_rdesc));
560 
561 	/* Receive status ring.  */
562 	addr = ep->descs_dma_addr + offsetof(struct ep93xx_descs, rstat);
563 	wrl(ep, REG_RXSTSQBADD, addr);
564 	wrl(ep, REG_RXSTSQCURADD, addr);
565 	wrw(ep, REG_RXSTSQBLEN, RX_QUEUE_ENTRIES * sizeof(struct ep93xx_rstat));
566 
567 	/* Transmit descriptor ring.  */
568 	addr = ep->descs_dma_addr + offsetof(struct ep93xx_descs, tdesc);
569 	wrl(ep, REG_TXDQBADD, addr);
570 	wrl(ep, REG_TXDQCURADD, addr);
571 	wrw(ep, REG_TXDQBLEN, TX_QUEUE_ENTRIES * sizeof(struct ep93xx_tdesc));
572 
573 	/* Transmit status ring.  */
574 	addr = ep->descs_dma_addr + offsetof(struct ep93xx_descs, tstat);
575 	wrl(ep, REG_TXSTSQBADD, addr);
576 	wrl(ep, REG_TXSTSQCURADD, addr);
577 	wrw(ep, REG_TXSTSQBLEN, TX_QUEUE_ENTRIES * sizeof(struct ep93xx_tstat));
578 
579 	wrl(ep, REG_BMCTL, REG_BMCTL_ENABLE_TX | REG_BMCTL_ENABLE_RX);
580 	wrl(ep, REG_INTEN, REG_INTEN_TX | REG_INTEN_RX);
581 	wrl(ep, REG_GIINTMSK, 0);
582 
583 	for (i = 0; i < 10; i++) {
584 		if ((rdl(ep, REG_BMSTS) & REG_BMSTS_RX_ACTIVE) != 0)
585 			break;
586 		msleep(1);
587 	}
588 
589 	if (i == 10) {
590 		pr_crit("hw failed to start\n");
591 		return 1;
592 	}
593 
594 	wrl(ep, REG_RXDENQ, RX_QUEUE_ENTRIES);
595 	wrl(ep, REG_RXSTSENQ, RX_QUEUE_ENTRIES);
596 
597 	wrb(ep, REG_INDAD0, dev->dev_addr[0]);
598 	wrb(ep, REG_INDAD1, dev->dev_addr[1]);
599 	wrb(ep, REG_INDAD2, dev->dev_addr[2]);
600 	wrb(ep, REG_INDAD3, dev->dev_addr[3]);
601 	wrb(ep, REG_INDAD4, dev->dev_addr[4]);
602 	wrb(ep, REG_INDAD5, dev->dev_addr[5]);
603 	wrl(ep, REG_AFP, 0);
604 
605 	wrl(ep, REG_MAXFRMLEN, (MAX_PKT_SIZE << 16) | MAX_PKT_SIZE);
606 
607 	wrl(ep, REG_RXCTL, REG_RXCTL_DEFAULT);
608 	wrl(ep, REG_TXCTL, REG_TXCTL_ENABLE);
609 
610 	return 0;
611 }
612 
613 static void ep93xx_stop_hw(struct net_device *dev)
614 {
615 	struct ep93xx_priv *ep = netdev_priv(dev);
616 	int i;
617 
618 	wrl(ep, REG_SELFCTL, REG_SELFCTL_RESET);
619 	for (i = 0; i < 10; i++) {
620 		if ((rdl(ep, REG_SELFCTL) & REG_SELFCTL_RESET) == 0)
621 			break;
622 		msleep(1);
623 	}
624 
625 	if (i == 10)
626 		pr_crit("hw failed to reset\n");
627 }
628 
629 static int ep93xx_open(struct net_device *dev)
630 {
631 	struct ep93xx_priv *ep = netdev_priv(dev);
632 	int err;
633 
634 	if (ep93xx_alloc_buffers(ep))
635 		return -ENOMEM;
636 
637 	napi_enable(&ep->napi);
638 
639 	if (ep93xx_start_hw(dev)) {
640 		napi_disable(&ep->napi);
641 		ep93xx_free_buffers(ep);
642 		return -EIO;
643 	}
644 
645 	spin_lock_init(&ep->rx_lock);
646 	ep->rx_pointer = 0;
647 	ep->tx_clean_pointer = 0;
648 	ep->tx_pointer = 0;
649 	spin_lock_init(&ep->tx_pending_lock);
650 	ep->tx_pending = 0;
651 
652 	err = request_irq(ep->irq, ep93xx_irq, IRQF_SHARED, dev->name, dev);
653 	if (err) {
654 		napi_disable(&ep->napi);
655 		ep93xx_stop_hw(dev);
656 		ep93xx_free_buffers(ep);
657 		return err;
658 	}
659 
660 	wrl(ep, REG_GIINTMSK, REG_GIINTMSK_ENABLE);
661 
662 	netif_start_queue(dev);
663 
664 	return 0;
665 }
666 
667 static int ep93xx_close(struct net_device *dev)
668 {
669 	struct ep93xx_priv *ep = netdev_priv(dev);
670 
671 	napi_disable(&ep->napi);
672 	netif_stop_queue(dev);
673 
674 	wrl(ep, REG_GIINTMSK, 0);
675 	free_irq(ep->irq, dev);
676 	ep93xx_stop_hw(dev);
677 	ep93xx_free_buffers(ep);
678 
679 	return 0;
680 }
681 
682 static int ep93xx_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
683 {
684 	struct ep93xx_priv *ep = netdev_priv(dev);
685 	struct mii_ioctl_data *data = if_mii(ifr);
686 
687 	return generic_mii_ioctl(&ep->mii, data, cmd, NULL);
688 }
689 
690 static void ep93xx_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
691 {
692 	strscpy(info->driver, DRV_MODULE_NAME, sizeof(info->driver));
693 }
694 
695 static int ep93xx_get_link_ksettings(struct net_device *dev,
696 				     struct ethtool_link_ksettings *cmd)
697 {
698 	struct ep93xx_priv *ep = netdev_priv(dev);
699 
700 	mii_ethtool_get_link_ksettings(&ep->mii, cmd);
701 
702 	return 0;
703 }
704 
705 static int ep93xx_set_link_ksettings(struct net_device *dev,
706 				     const struct ethtool_link_ksettings *cmd)
707 {
708 	struct ep93xx_priv *ep = netdev_priv(dev);
709 	return mii_ethtool_set_link_ksettings(&ep->mii, cmd);
710 }
711 
712 static int ep93xx_nway_reset(struct net_device *dev)
713 {
714 	struct ep93xx_priv *ep = netdev_priv(dev);
715 	return mii_nway_restart(&ep->mii);
716 }
717 
718 static u32 ep93xx_get_link(struct net_device *dev)
719 {
720 	struct ep93xx_priv *ep = netdev_priv(dev);
721 	return mii_link_ok(&ep->mii);
722 }
723 
724 static const struct ethtool_ops ep93xx_ethtool_ops = {
725 	.get_drvinfo		= ep93xx_get_drvinfo,
726 	.nway_reset		= ep93xx_nway_reset,
727 	.get_link		= ep93xx_get_link,
728 	.get_link_ksettings	= ep93xx_get_link_ksettings,
729 	.set_link_ksettings	= ep93xx_set_link_ksettings,
730 };
731 
732 static const struct net_device_ops ep93xx_netdev_ops = {
733 	.ndo_open		= ep93xx_open,
734 	.ndo_stop		= ep93xx_close,
735 	.ndo_start_xmit		= ep93xx_xmit,
736 	.ndo_eth_ioctl		= ep93xx_ioctl,
737 	.ndo_validate_addr	= eth_validate_addr,
738 	.ndo_set_mac_address	= eth_mac_addr,
739 };
740 
741 static struct net_device *ep93xx_dev_alloc(struct ep93xx_eth_data *data)
742 {
743 	struct net_device *dev;
744 
745 	dev = alloc_etherdev(sizeof(struct ep93xx_priv));
746 	if (dev == NULL)
747 		return NULL;
748 
749 	eth_hw_addr_set(dev, data->dev_addr);
750 
751 	dev->ethtool_ops = &ep93xx_ethtool_ops;
752 	dev->netdev_ops = &ep93xx_netdev_ops;
753 
754 	dev->features |= NETIF_F_SG | NETIF_F_HW_CSUM;
755 
756 	return dev;
757 }
758 
759 
760 static void ep93xx_eth_remove(struct platform_device *pdev)
761 {
762 	struct net_device *dev;
763 	struct ep93xx_priv *ep;
764 	struct resource *mem;
765 
766 	dev = platform_get_drvdata(pdev);
767 	if (dev == NULL)
768 		return;
769 
770 	ep = netdev_priv(dev);
771 
772 	/* @@@ Force down.  */
773 	unregister_netdev(dev);
774 	ep93xx_free_buffers(ep);
775 
776 	if (ep->base_addr != NULL)
777 		iounmap(ep->base_addr);
778 
779 	if (ep->res != NULL) {
780 		mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
781 		release_mem_region(mem->start, resource_size(mem));
782 	}
783 
784 	free_netdev(dev);
785 }
786 
787 static int ep93xx_eth_probe(struct platform_device *pdev)
788 {
789 	struct ep93xx_eth_data *data;
790 	struct net_device *dev;
791 	struct ep93xx_priv *ep;
792 	struct resource *mem;
793 	int irq;
794 	int err;
795 
796 	if (pdev == NULL)
797 		return -ENODEV;
798 	data = dev_get_platdata(&pdev->dev);
799 
800 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
801 	irq = platform_get_irq(pdev, 0);
802 	if (!mem || irq < 0)
803 		return -ENXIO;
804 
805 	dev = ep93xx_dev_alloc(data);
806 	if (dev == NULL) {
807 		err = -ENOMEM;
808 		goto err_out;
809 	}
810 	ep = netdev_priv(dev);
811 	ep->dev = dev;
812 	SET_NETDEV_DEV(dev, &pdev->dev);
813 	netif_napi_add(dev, &ep->napi, ep93xx_poll);
814 
815 	platform_set_drvdata(pdev, dev);
816 
817 	ep->res = request_mem_region(mem->start, resource_size(mem),
818 				     dev_name(&pdev->dev));
819 	if (ep->res == NULL) {
820 		dev_err(&pdev->dev, "Could not reserve memory region\n");
821 		err = -ENOMEM;
822 		goto err_out;
823 	}
824 
825 	ep->base_addr = ioremap(mem->start, resource_size(mem));
826 	if (ep->base_addr == NULL) {
827 		dev_err(&pdev->dev, "Failed to ioremap ethernet registers\n");
828 		err = -EIO;
829 		goto err_out;
830 	}
831 	ep->irq = irq;
832 
833 	ep->mii.phy_id = data->phy_id;
834 	ep->mii.phy_id_mask = 0x1f;
835 	ep->mii.reg_num_mask = 0x1f;
836 	ep->mii.dev = dev;
837 	ep->mii.mdio_read = ep93xx_mdio_read;
838 	ep->mii.mdio_write = ep93xx_mdio_write;
839 	ep->mdc_divisor = 40;	/* Max HCLK 100 MHz, min MDIO clk 2.5 MHz.  */
840 
841 	if (is_zero_ether_addr(dev->dev_addr))
842 		eth_hw_addr_random(dev);
843 
844 	err = register_netdev(dev);
845 	if (err) {
846 		dev_err(&pdev->dev, "Failed to register netdev\n");
847 		goto err_out;
848 	}
849 
850 	printk(KERN_INFO "%s: ep93xx on-chip ethernet, IRQ %d, %pM\n",
851 			dev->name, ep->irq, dev->dev_addr);
852 
853 	return 0;
854 
855 err_out:
856 	ep93xx_eth_remove(pdev);
857 	return err;
858 }
859 
860 
861 static struct platform_driver ep93xx_eth_driver = {
862 	.probe		= ep93xx_eth_probe,
863 	.remove_new	= ep93xx_eth_remove,
864 	.driver		= {
865 		.name	= "ep93xx-eth",
866 	},
867 };
868 
869 module_platform_driver(ep93xx_eth_driver);
870 
871 MODULE_DESCRIPTION("Cirrus EP93xx Ethernet driver");
872 MODULE_LICENSE("GPL");
873 MODULE_ALIAS("platform:ep93xx-eth");
874