1/*
2 * sgiseeq.c: Seeq8003 ethernet driver for SGI machines.
3 *
4 * Copyright (C) 1996 David S. Miller (dm@engr.sgi.com)
5 */
6
7#undef DEBUG
8
9#include <linux/kernel.h>
10#include <linux/module.h>
11#include <linux/errno.h>
12#include <linux/init.h>
13#include <linux/types.h>
14#include <linux/interrupt.h>
15#include <linux/slab.h>
16#include <linux/string.h>
17#include <linux/delay.h>
18#include <linux/netdevice.h>
19#include <linux/platform_device.h>
20#include <linux/etherdevice.h>
21#include <linux/skbuff.h>
22
23#include <asm/sgi/hpc3.h>
24#include <asm/sgi/ip22.h>
25#include <asm/sgi/seeq.h>
26
27#include "sgiseeq.h"
28
29static char *sgiseeqstr = "SGI Seeq8003";
30
31/*
32 * If you want speed, you do something silly, it always has worked for me.  So,
33 * with that in mind, I've decided to make this driver look completely like a
34 * stupid Lance from a driver architecture perspective.  Only difference is that
35 * here our "ring buffer" looks and acts like a real Lance one does but is
36 * layed out like how the HPC DMA and the Seeq want it to.  You'd be surprised
37 * how a stupid idea like this can pay off in performance, not to mention
38 * making this driver 2,000 times easier to write. ;-)
39 */
40
41/* Tune these if we tend to run out often etc. */
42#define SEEQ_RX_BUFFERS  16
43#define SEEQ_TX_BUFFERS  16
44
45#define PKT_BUF_SZ       1584
46
47#define NEXT_RX(i)  (((i) + 1) & (SEEQ_RX_BUFFERS - 1))
48#define NEXT_TX(i)  (((i) + 1) & (SEEQ_TX_BUFFERS - 1))
49#define PREV_RX(i)  (((i) - 1) & (SEEQ_RX_BUFFERS - 1))
50#define PREV_TX(i)  (((i) - 1) & (SEEQ_TX_BUFFERS - 1))
51
52#define TX_BUFFS_AVAIL(sp) ((sp->tx_old <= sp->tx_new) ? \
53			    sp->tx_old + (SEEQ_TX_BUFFERS - 1) - sp->tx_new : \
54			    sp->tx_old - sp->tx_new - 1)
55
56struct sgiseeq_rx_desc {
57	volatile struct hpc_dma_desc rdma;
58	volatile signed int buf_vaddr;
59};
60
61struct sgiseeq_tx_desc {
62	volatile struct hpc_dma_desc tdma;
63	volatile signed int buf_vaddr;
64};
65
66/*
67 * Warning: This structure is layed out in a certain way because HPC dma
68 *          descriptors must be 8-byte aligned.  So don't touch this without
69 *          some care.
70 */
71struct sgiseeq_init_block { /* Note the name ;-) */
72	struct sgiseeq_rx_desc rxvector[SEEQ_RX_BUFFERS];
73	struct sgiseeq_tx_desc txvector[SEEQ_TX_BUFFERS];
74};
75
76struct sgiseeq_private {
77	struct sgiseeq_init_block *srings;
78
79	/* Ptrs to the descriptors in uncached space. */
80	struct sgiseeq_rx_desc *rx_desc;
81	struct sgiseeq_tx_desc *tx_desc;
82
83	char *name;
84	struct hpc3_ethregs *hregs;
85	struct sgiseeq_regs *sregs;
86
87	/* Ring entry counters. */
88	unsigned int rx_new, tx_new;
89	unsigned int rx_old, tx_old;
90
91	int is_edlc;
92	unsigned char control;
93	unsigned char mode;
94
95	struct net_device_stats stats;
96
97	spinlock_t tx_lock;
98};
99
100static inline void hpc3_eth_reset(struct hpc3_ethregs *hregs)
101{
102	hregs->reset = HPC3_ERST_CRESET | HPC3_ERST_CLRIRQ;
103	udelay(20);
104	hregs->reset = 0;
105}
106
107static inline void reset_hpc3_and_seeq(struct hpc3_ethregs *hregs,
108				       struct sgiseeq_regs *sregs)
109{
110	hregs->rx_ctrl = hregs->tx_ctrl = 0;
111	hpc3_eth_reset(hregs);
112}
113
114#define RSTAT_GO_BITS (SEEQ_RCMD_IGOOD | SEEQ_RCMD_IEOF | SEEQ_RCMD_ISHORT | \
115		       SEEQ_RCMD_IDRIB | SEEQ_RCMD_ICRC)
116
117static inline void seeq_go(struct sgiseeq_private *sp,
118			   struct hpc3_ethregs *hregs,
119			   struct sgiseeq_regs *sregs)
120{
121	sregs->rstat = sp->mode | RSTAT_GO_BITS;
122	hregs->rx_ctrl = HPC3_ERXCTRL_ACTIVE;
123}
124
125static inline void __sgiseeq_set_mac_address(struct net_device *dev)
126{
127	struct sgiseeq_private *sp = netdev_priv(dev);
128	struct sgiseeq_regs *sregs = sp->sregs;
129	int i;
130
131	sregs->tstat = SEEQ_TCMD_RB0;
132	for (i = 0; i < 6; i++)
133		sregs->rw.eth_addr[i] = dev->dev_addr[i];
134}
135
136static int sgiseeq_set_mac_address(struct net_device *dev, void *addr)
137{
138	struct sgiseeq_private *sp = netdev_priv(dev);
139	struct sockaddr *sa = addr;
140
141	memcpy(dev->dev_addr, sa->sa_data, dev->addr_len);
142
143	spin_lock_irq(&sp->tx_lock);
144	__sgiseeq_set_mac_address(dev);
145	spin_unlock_irq(&sp->tx_lock);
146
147	return 0;
148}
149
150#define TCNTINFO_INIT (HPCDMA_EOX | HPCDMA_ETXD)
151#define RCNTCFG_INIT  (HPCDMA_OWN | HPCDMA_EORP | HPCDMA_XIE)
152#define RCNTINFO_INIT (RCNTCFG_INIT | (PKT_BUF_SZ & HPCDMA_BCNT))
153
154static int seeq_init_ring(struct net_device *dev)
155{
156	struct sgiseeq_private *sp = netdev_priv(dev);
157	int i;
158
159	netif_stop_queue(dev);
160	sp->rx_new = sp->tx_new = 0;
161	sp->rx_old = sp->tx_old = 0;
162
163	__sgiseeq_set_mac_address(dev);
164
165	/* Setup tx ring. */
166	for(i = 0; i < SEEQ_TX_BUFFERS; i++) {
167		if (!sp->tx_desc[i].tdma.pbuf) {
168			unsigned long buffer;
169
170			buffer = (unsigned long) kmalloc(PKT_BUF_SZ, GFP_KERNEL);
171			if (!buffer)
172				return -ENOMEM;
173			sp->tx_desc[i].buf_vaddr = CKSEG1ADDR(buffer);
174			sp->tx_desc[i].tdma.pbuf = CPHYSADDR(buffer);
175		}
176		sp->tx_desc[i].tdma.cntinfo = TCNTINFO_INIT;
177	}
178
179	/* And now the rx ring. */
180	for (i = 0; i < SEEQ_RX_BUFFERS; i++) {
181		if (!sp->rx_desc[i].rdma.pbuf) {
182			unsigned long buffer;
183
184			buffer = (unsigned long) kmalloc(PKT_BUF_SZ, GFP_KERNEL);
185			if (!buffer)
186				return -ENOMEM;
187			sp->rx_desc[i].buf_vaddr = CKSEG1ADDR(buffer);
188			sp->rx_desc[i].rdma.pbuf = CPHYSADDR(buffer);
189		}
190		sp->rx_desc[i].rdma.cntinfo = RCNTINFO_INIT;
191	}
192	sp->rx_desc[i - 1].rdma.cntinfo |= HPCDMA_EOR;
193	return 0;
194}
195
196#ifdef DEBUG
197static struct sgiseeq_private *gpriv;
198static struct net_device *gdev;
199
200static void sgiseeq_dump_rings(void)
201{
202	static int once;
203	struct sgiseeq_rx_desc *r = gpriv->rx_desc;
204	struct sgiseeq_tx_desc *t = gpriv->tx_desc;
205	struct hpc3_ethregs *hregs = gpriv->hregs;
206	int i;
207
208	if (once)
209		return;
210	once++;
211	printk("RING DUMP:\n");
212	for (i = 0; i < SEEQ_RX_BUFFERS; i++) {
213		printk("RX [%d]: @(%p) [%08x,%08x,%08x] ",
214		       i, (&r[i]), r[i].rdma.pbuf, r[i].rdma.cntinfo,
215		       r[i].rdma.pnext);
216		i += 1;
217		printk("-- [%d]: @(%p) [%08x,%08x,%08x]\n",
218		       i, (&r[i]), r[i].rdma.pbuf, r[i].rdma.cntinfo,
219		       r[i].rdma.pnext);
220	}
221	for (i = 0; i < SEEQ_TX_BUFFERS; i++) {
222		printk("TX [%d]: @(%p) [%08x,%08x,%08x] ",
223		       i, (&t[i]), t[i].tdma.pbuf, t[i].tdma.cntinfo,
224		       t[i].tdma.pnext);
225		i += 1;
226		printk("-- [%d]: @(%p) [%08x,%08x,%08x]\n",
227		       i, (&t[i]), t[i].tdma.pbuf, t[i].tdma.cntinfo,
228		       t[i].tdma.pnext);
229	}
230	printk("INFO: [rx_new = %d rx_old=%d] [tx_new = %d tx_old = %d]\n",
231	       gpriv->rx_new, gpriv->rx_old, gpriv->tx_new, gpriv->tx_old);
232	printk("RREGS: rx_cbptr[%08x] rx_ndptr[%08x] rx_ctrl[%08x]\n",
233	       hregs->rx_cbptr, hregs->rx_ndptr, hregs->rx_ctrl);
234	printk("TREGS: tx_cbptr[%08x] tx_ndptr[%08x] tx_ctrl[%08x]\n",
235	       hregs->tx_cbptr, hregs->tx_ndptr, hregs->tx_ctrl);
236}
237#endif
238
239#define TSTAT_INIT_SEEQ (SEEQ_TCMD_IPT|SEEQ_TCMD_I16|SEEQ_TCMD_IC|SEEQ_TCMD_IUF)
240#define TSTAT_INIT_EDLC ((TSTAT_INIT_SEEQ) | SEEQ_TCMD_RB2)
241
242static int init_seeq(struct net_device *dev, struct sgiseeq_private *sp,
243		     struct sgiseeq_regs *sregs)
244{
245	struct hpc3_ethregs *hregs = sp->hregs;
246	int err;
247
248	reset_hpc3_and_seeq(hregs, sregs);
249	err = seeq_init_ring(dev);
250	if (err)
251		return err;
252
253	/* Setup to field the proper interrupt types. */
254	if (sp->is_edlc) {
255		sregs->tstat = TSTAT_INIT_EDLC;
256		sregs->rw.wregs.control = sp->control;
257		sregs->rw.wregs.frame_gap = 0;
258	} else {
259		sregs->tstat = TSTAT_INIT_SEEQ;
260	}
261
262	hregs->rx_ndptr = CPHYSADDR(sp->rx_desc);
263	hregs->tx_ndptr = CPHYSADDR(sp->tx_desc);
264
265	seeq_go(sp, hregs, sregs);
266	return 0;
267}
268
269static inline void record_rx_errors(struct sgiseeq_private *sp,
270				    unsigned char status)
271{
272	if (status & SEEQ_RSTAT_OVERF ||
273	    status & SEEQ_RSTAT_SFRAME)
274		sp->stats.rx_over_errors++;
275	if (status & SEEQ_RSTAT_CERROR)
276		sp->stats.rx_crc_errors++;
277	if (status & SEEQ_RSTAT_DERROR)
278		sp->stats.rx_frame_errors++;
279	if (status & SEEQ_RSTAT_REOF)
280		sp->stats.rx_errors++;
281}
282
283static inline void rx_maybe_restart(struct sgiseeq_private *sp,
284				    struct hpc3_ethregs *hregs,
285				    struct sgiseeq_regs *sregs)
286{
287	if (!(hregs->rx_ctrl & HPC3_ERXCTRL_ACTIVE)) {
288		hregs->rx_ndptr = CPHYSADDR(sp->rx_desc + sp->rx_new);
289		seeq_go(sp, hregs, sregs);
290	}
291}
292
293#define for_each_rx(rd, sp) for((rd) = &(sp)->rx_desc[(sp)->rx_new]; \
294				!((rd)->rdma.cntinfo & HPCDMA_OWN); \
295				(rd) = &(sp)->rx_desc[(sp)->rx_new])
296
297static inline void sgiseeq_rx(struct net_device *dev, struct sgiseeq_private *sp,
298			      struct hpc3_ethregs *hregs,
299			      struct sgiseeq_regs *sregs)
300{
301	struct sgiseeq_rx_desc *rd;
302	struct sk_buff *skb = NULL;
303	unsigned char pkt_status;
304	unsigned char *pkt_pointer = NULL;
305	int len = 0;
306	unsigned int orig_end = PREV_RX(sp->rx_new);
307
308	/* Service every received packet. */
309	for_each_rx(rd, sp) {
310		len = PKT_BUF_SZ - (rd->rdma.cntinfo & HPCDMA_BCNT) - 3;
311		pkt_pointer = (unsigned char *)(long)rd->buf_vaddr;
312		pkt_status = pkt_pointer[len + 2];
313
314		if (pkt_status & SEEQ_RSTAT_FIG) {
315			/* Packet is OK. */
316			skb = dev_alloc_skb(len + 2);
317
318			if (skb) {
319				skb_reserve(skb, 2);
320				skb_put(skb, len);
321
322				/* Copy out of kseg1 to avoid silly cache flush. */
323				eth_copy_and_sum(skb, pkt_pointer + 2, len, 0);
324				skb->protocol = eth_type_trans(skb, dev);
325
326				/* We don't want to receive our own packets */
327				if (memcmp(eth_hdr(skb)->h_source, dev->dev_addr, ETH_ALEN)) {
328					netif_rx(skb);
329					dev->last_rx = jiffies;
330					sp->stats.rx_packets++;
331					sp->stats.rx_bytes += len;
332				} else {
333					/* Silently drop my own packets */
334					dev_kfree_skb_irq(skb);
335				}
336			} else {
337				printk (KERN_NOTICE "%s: Memory squeeze, deferring packet.\n",
338					dev->name);
339				sp->stats.rx_dropped++;
340			}
341		} else {
342			record_rx_errors(sp, pkt_status);
343		}
344
345		/* Return the entry to the ring pool. */
346		rd->rdma.cntinfo = RCNTINFO_INIT;
347		sp->rx_new = NEXT_RX(sp->rx_new);
348	}
349	sp->rx_desc[orig_end].rdma.cntinfo &= ~(HPCDMA_EOR);
350	sp->rx_desc[PREV_RX(sp->rx_new)].rdma.cntinfo |= HPCDMA_EOR;
351	rx_maybe_restart(sp, hregs, sregs);
352}
353
354static inline void tx_maybe_reset_collisions(struct sgiseeq_private *sp,
355					     struct sgiseeq_regs *sregs)
356{
357	if (sp->is_edlc) {
358		sregs->rw.wregs.control = sp->control & ~(SEEQ_CTRL_XCNT);
359		sregs->rw.wregs.control = sp->control;
360	}
361}
362
363static inline void kick_tx(struct sgiseeq_tx_desc *td,
364			   struct hpc3_ethregs *hregs)
365{
366	/* If the HPC aint doin nothin, and there are more packets
367	 * with ETXD cleared and XIU set we must make very certain
368	 * that we restart the HPC else we risk locking up the
369	 * adapter.  The following code is only safe iff the HPCDMA
370	 * is not active!
371	 */
372	while ((td->tdma.cntinfo & (HPCDMA_XIU | HPCDMA_ETXD)) ==
373	      (HPCDMA_XIU | HPCDMA_ETXD))
374		td = (struct sgiseeq_tx_desc *)(long) CKSEG1ADDR(td->tdma.pnext);
375	if (td->tdma.cntinfo & HPCDMA_XIU) {
376		hregs->tx_ndptr = CPHYSADDR(td);
377		hregs->tx_ctrl = HPC3_ETXCTRL_ACTIVE;
378	}
379}
380
381static inline void sgiseeq_tx(struct net_device *dev, struct sgiseeq_private *sp,
382			      struct hpc3_ethregs *hregs,
383			      struct sgiseeq_regs *sregs)
384{
385	struct sgiseeq_tx_desc *td;
386	unsigned long status = hregs->tx_ctrl;
387	int j;
388
389	tx_maybe_reset_collisions(sp, sregs);
390
391	if (!(status & (HPC3_ETXCTRL_ACTIVE | SEEQ_TSTAT_PTRANS))) {
392		/* Oops, HPC detected some sort of error. */
393		if (status & SEEQ_TSTAT_R16)
394			sp->stats.tx_aborted_errors++;
395		if (status & SEEQ_TSTAT_UFLOW)
396			sp->stats.tx_fifo_errors++;
397		if (status & SEEQ_TSTAT_LCLS)
398			sp->stats.collisions++;
399	}
400
401	/* Ack 'em... */
402	for (j = sp->tx_old; j != sp->tx_new; j = NEXT_TX(j)) {
403		td = &sp->tx_desc[j];
404
405		if (!(td->tdma.cntinfo & (HPCDMA_XIU)))
406			break;
407		if (!(td->tdma.cntinfo & (HPCDMA_ETXD))) {
408			if (!(status & HPC3_ETXCTRL_ACTIVE)) {
409				hregs->tx_ndptr = CPHYSADDR(td);
410				hregs->tx_ctrl = HPC3_ETXCTRL_ACTIVE;
411			}
412			break;
413		}
414		sp->stats.tx_packets++;
415		sp->tx_old = NEXT_TX(sp->tx_old);
416		td->tdma.cntinfo &= ~(HPCDMA_XIU | HPCDMA_XIE);
417		td->tdma.cntinfo |= HPCDMA_EOX;
418	}
419}
420
421static irqreturn_t sgiseeq_interrupt(int irq, void *dev_id)
422{
423	struct net_device *dev = (struct net_device *) dev_id;
424	struct sgiseeq_private *sp = netdev_priv(dev);
425	struct hpc3_ethregs *hregs = sp->hregs;
426	struct sgiseeq_regs *sregs = sp->sregs;
427
428	spin_lock(&sp->tx_lock);
429
430	/* Ack the IRQ and set software state. */
431	hregs->reset = HPC3_ERST_CLRIRQ;
432
433	/* Always check for received packets. */
434	sgiseeq_rx(dev, sp, hregs, sregs);
435
436	/* Only check for tx acks if we have something queued. */
437	if (sp->tx_old != sp->tx_new)
438		sgiseeq_tx(dev, sp, hregs, sregs);
439
440	if ((TX_BUFFS_AVAIL(sp) > 0) && netif_queue_stopped(dev)) {
441		netif_wake_queue(dev);
442	}
443	spin_unlock(&sp->tx_lock);
444
445	return IRQ_HANDLED;
446}
447
448static int sgiseeq_open(struct net_device *dev)
449{
450	struct sgiseeq_private *sp = netdev_priv(dev);
451	struct sgiseeq_regs *sregs = sp->sregs;
452	unsigned int irq = dev->irq;
453	int err;
454
455	if (request_irq(irq, sgiseeq_interrupt, 0, sgiseeqstr, dev)) {
456		printk(KERN_ERR "Seeq8003: Can't get irq %d\n", dev->irq);
457		err = -EAGAIN;
458	}
459
460	err = init_seeq(dev, sp, sregs);
461	if (err)
462		goto out_free_irq;
463
464	netif_start_queue(dev);
465
466	return 0;
467
468out_free_irq:
469	free_irq(irq, dev);
470
471	return err;
472}
473
474static int sgiseeq_close(struct net_device *dev)
475{
476	struct sgiseeq_private *sp = netdev_priv(dev);
477	struct sgiseeq_regs *sregs = sp->sregs;
478	unsigned int irq = dev->irq;
479
480	netif_stop_queue(dev);
481
482	/* Shutdown the Seeq. */
483	reset_hpc3_and_seeq(sp->hregs, sregs);
484	free_irq(irq, dev);
485
486	return 0;
487}
488
489static inline int sgiseeq_reset(struct net_device *dev)
490{
491	struct sgiseeq_private *sp = netdev_priv(dev);
492	struct sgiseeq_regs *sregs = sp->sregs;
493	int err;
494
495	err = init_seeq(dev, sp, sregs);
496	if (err)
497		return err;
498
499	dev->trans_start = jiffies;
500	netif_wake_queue(dev);
501
502	return 0;
503}
504
505static int sgiseeq_start_xmit(struct sk_buff *skb, struct net_device *dev)
506{
507	struct sgiseeq_private *sp = netdev_priv(dev);
508	struct hpc3_ethregs *hregs = sp->hregs;
509	unsigned long flags;
510	struct sgiseeq_tx_desc *td;
511	int skblen, len, entry;
512
513	spin_lock_irqsave(&sp->tx_lock, flags);
514
515	/* Setup... */
516	skblen = skb->len;
517	len = (skblen <= ETH_ZLEN) ? ETH_ZLEN : skblen;
518	sp->stats.tx_bytes += len;
519	entry = sp->tx_new;
520	td = &sp->tx_desc[entry];
521
522	/* Create entry.  There are so many races with adding a new
523	 * descriptor to the chain:
524	 * 1) Assume that the HPC is off processing a DMA chain while
525	 *    we are changing all of the following.
526	 * 2) Do no allow the HPC to look at a new descriptor until
527	 *    we have completely set up it's state.  This means, do
528	 *    not clear HPCDMA_EOX in the current last descritptor
529	 *    until the one we are adding looks consistent and could
530	 *    be processes right now.
531	 * 3) The tx interrupt code must notice when we've added a new
532	 *    entry and the HPC got to the end of the chain before we
533	 *    added this new entry and restarted it.
534	 */
535	skb_copy_from_linear_data(skb, (char *)(long)td->buf_vaddr, skblen);
536	if (len != skblen)
537		memset((char *)(long)td->buf_vaddr + skb->len, 0, len-skblen);
538	td->tdma.cntinfo = (len & HPCDMA_BCNT) |
539	                   HPCDMA_XIU | HPCDMA_EOXP | HPCDMA_XIE | HPCDMA_EOX;
540	if (sp->tx_old != sp->tx_new) {
541		struct sgiseeq_tx_desc *backend;
542
543		backend = &sp->tx_desc[PREV_TX(sp->tx_new)];
544		backend->tdma.cntinfo &= ~HPCDMA_EOX;
545	}
546	sp->tx_new = NEXT_TX(sp->tx_new); /* Advance. */
547
548	/* Maybe kick the HPC back into motion. */
549	if (!(hregs->tx_ctrl & HPC3_ETXCTRL_ACTIVE))
550		kick_tx(&sp->tx_desc[sp->tx_old], hregs);
551
552	dev->trans_start = jiffies;
553	dev_kfree_skb(skb);
554
555	if (!TX_BUFFS_AVAIL(sp))
556		netif_stop_queue(dev);
557	spin_unlock_irqrestore(&sp->tx_lock, flags);
558
559	return 0;
560}
561
562static void timeout(struct net_device *dev)
563{
564	printk(KERN_NOTICE "%s: transmit timed out, resetting\n", dev->name);
565	sgiseeq_reset(dev);
566
567	dev->trans_start = jiffies;
568	netif_wake_queue(dev);
569}
570
571static struct net_device_stats *sgiseeq_get_stats(struct net_device *dev)
572{
573	struct sgiseeq_private *sp = netdev_priv(dev);
574
575	return &sp->stats;
576}
577
578static void sgiseeq_set_multicast(struct net_device *dev)
579{
580	struct sgiseeq_private *sp = (struct sgiseeq_private *) dev->priv;
581	unsigned char oldmode = sp->mode;
582
583	if(dev->flags & IFF_PROMISC)
584		sp->mode = SEEQ_RCMD_RANY;
585	else if ((dev->flags & IFF_ALLMULTI) || dev->mc_count)
586		sp->mode = SEEQ_RCMD_RBMCAST;
587	else
588		sp->mode = SEEQ_RCMD_RBCAST;
589
590
591	if (oldmode != sp->mode)
592		sgiseeq_reset(dev);
593}
594
595static inline void setup_tx_ring(struct sgiseeq_tx_desc *buf, int nbufs)
596{
597	int i = 0;
598
599	while (i < (nbufs - 1)) {
600		buf[i].tdma.pnext = CPHYSADDR(buf + i + 1);
601		buf[i].tdma.pbuf = 0;
602		i++;
603	}
604	buf[i].tdma.pnext = CPHYSADDR(buf);
605}
606
607static inline void setup_rx_ring(struct sgiseeq_rx_desc *buf, int nbufs)
608{
609	int i = 0;
610
611	while (i < (nbufs - 1)) {
612		buf[i].rdma.pnext = CPHYSADDR(buf + i + 1);
613		buf[i].rdma.pbuf = 0;
614		i++;
615	}
616	buf[i].rdma.pbuf = 0;
617	buf[i].rdma.pnext = CPHYSADDR(buf);
618}
619
620#define ALIGNED(x)  ((((unsigned long)(x)) + 0xf) & ~(0xf))
621
622static int __init sgiseeq_probe(struct platform_device *pdev)
623{
624	struct sgiseeq_platform_data *pd = pdev->dev.platform_data;
625	struct hpc3_regs *hpcregs = pd->hpc;
626	struct sgiseeq_init_block *sr;
627	unsigned int irq = pd->irq;
628	struct sgiseeq_private *sp;
629	struct net_device *dev;
630	int err, i;
631
632	dev = alloc_etherdev(sizeof (struct sgiseeq_private));
633	if (!dev) {
634		printk(KERN_ERR "Sgiseeq: Etherdev alloc failed, aborting.\n");
635		err = -ENOMEM;
636		goto err_out;
637	}
638
639	platform_set_drvdata(pdev, dev);
640	sp = netdev_priv(dev);
641
642	/* Make private data page aligned */
643	sr = (struct sgiseeq_init_block *) get_zeroed_page(GFP_KERNEL);
644	if (!sr) {
645		printk(KERN_ERR "Sgiseeq: Page alloc failed, aborting.\n");
646		err = -ENOMEM;
647		goto err_out_free_dev;
648	}
649	sp->srings = sr;
650
651	memcpy(dev->dev_addr, pd->mac, ETH_ALEN);
652
653#ifdef DEBUG
654	gpriv = sp;
655	gdev = dev;
656#endif
657	sp->sregs = (struct sgiseeq_regs *) &hpcregs->eth_ext[0];
658	sp->hregs = &hpcregs->ethregs;
659	sp->name = sgiseeqstr;
660	sp->mode = SEEQ_RCMD_RBCAST;
661
662	sp->rx_desc = (struct sgiseeq_rx_desc *)
663	              CKSEG1ADDR(ALIGNED(&sp->srings->rxvector[0]));
664	dma_cache_wback_inv((unsigned long)&sp->srings->rxvector,
665	                    sizeof(sp->srings->rxvector));
666	sp->tx_desc = (struct sgiseeq_tx_desc *)
667	              CKSEG1ADDR(ALIGNED(&sp->srings->txvector[0]));
668	dma_cache_wback_inv((unsigned long)&sp->srings->txvector,
669	                    sizeof(sp->srings->txvector));
670
671	/* A couple calculations now, saves many cycles later. */
672	setup_rx_ring(sp->rx_desc, SEEQ_RX_BUFFERS);
673	setup_tx_ring(sp->tx_desc, SEEQ_TX_BUFFERS);
674
675	/* Setup PIO and DMA transfer timing */
676	sp->hregs->pconfig = 0x161;
677	sp->hregs->dconfig = HPC3_EDCFG_FIRQ | HPC3_EDCFG_FEOP |
678			     HPC3_EDCFG_FRXDC | HPC3_EDCFG_PTO | 0x026;
679
680	/* Setup PIO and DMA transfer timing */
681	sp->hregs->pconfig = 0x161;
682	sp->hregs->dconfig = HPC3_EDCFG_FIRQ | HPC3_EDCFG_FEOP |
683			     HPC3_EDCFG_FRXDC | HPC3_EDCFG_PTO | 0x026;
684
685	/* Reset the chip. */
686	hpc3_eth_reset(sp->hregs);
687
688	sp->is_edlc = !(sp->sregs->rw.rregs.collision_tx[0] & 0xff);
689	if (sp->is_edlc)
690		sp->control = SEEQ_CTRL_XCNT | SEEQ_CTRL_ACCNT |
691			      SEEQ_CTRL_SFLAG | SEEQ_CTRL_ESHORT |
692			      SEEQ_CTRL_ENCARR;
693
694	dev->open		= sgiseeq_open;
695	dev->stop		= sgiseeq_close;
696	dev->hard_start_xmit	= sgiseeq_start_xmit;
697	dev->tx_timeout		= timeout;
698	dev->watchdog_timeo	= (200 * HZ) / 1000;
699	dev->get_stats		= sgiseeq_get_stats;
700	dev->set_multicast_list	= sgiseeq_set_multicast;
701	dev->set_mac_address	= sgiseeq_set_mac_address;
702	dev->irq		= irq;
703
704	if (register_netdev(dev)) {
705		printk(KERN_ERR "Sgiseeq: Cannot register net device, "
706		       "aborting.\n");
707		err = -ENODEV;
708		goto err_out_free_page;
709	}
710
711	printk(KERN_INFO "%s: %s ", dev->name, sgiseeqstr);
712	for (i = 0; i < 6; i++)
713		printk("%2.2x%c", dev->dev_addr[i], i == 5 ? '\n' : ':');
714
715	return 0;
716
717err_out_free_page:
718	free_page((unsigned long) sp->srings);
719err_out_free_dev:
720	kfree(dev);
721
722err_out:
723	return err;
724}
725
726static void __exit sgiseeq_remove(struct platform_device *pdev)
727{
728	struct net_device *dev = platform_get_drvdata(pdev);
729	struct sgiseeq_private *sp = netdev_priv(dev);
730
731	unregister_netdev(dev);
732	free_page((unsigned long) sp->srings);
733	free_netdev(dev);
734	platform_set_drvdata(pdev, NULL);
735}
736
737static struct platform_driver sgiseeq_driver = {
738	.probe	= sgiseeq_probe,
739	.remove	= __devexit_p(sgiseeq_remove),
740	.driver = {
741		.name	= "sgiseeq"
742	}
743};
744
745static int __init sgiseeq_module_init(void)
746{
747	if (platform_driver_register(&sgiseeq_driver)) {
748		printk(KERN_ERR "Driver registration failed\n");
749		return -ENODEV;
750	}
751
752	return 0;
753}
754
755static void __exit sgiseeq_module_exit(void)
756{
757	platform_driver_unregister(&sgiseeq_driver);
758}
759
760module_init(sgiseeq_module_init);
761module_exit(sgiseeq_module_exit);
762
763MODULE_DESCRIPTION("SGI Seeq 8003 driver");
764MODULE_AUTHOR("Linux/MIPS Mailing List <linux-mips@linux-mips.org>");
765MODULE_LICENSE("GPL");
766