1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * sgiseeq.c: Seeq8003 ethernet driver for SGI machines.
4 *
5 * Copyright (C) 1996 David S. Miller (davem@davemloft.net)
6 */
7
8#undef DEBUG
9
10#include <linux/dma-mapping.h>
11#include <linux/kernel.h>
12#include <linux/module.h>
13#include <linux/slab.h>
14#include <linux/errno.h>
15#include <linux/types.h>
16#include <linux/interrupt.h>
17#include <linux/string.h>
18#include <linux/delay.h>
19#include <linux/netdevice.h>
20#include <linux/platform_device.h>
21#include <linux/etherdevice.h>
22#include <linux/skbuff.h>
23
24#include <asm/sgi/hpc3.h>
25#include <asm/sgi/ip22.h>
26#include <asm/sgi/seeq.h>
27
28#include "sgiseeq.h"
29
30static char *sgiseeqstr = "SGI Seeq8003";
31
32/*
33 * If you want speed, you do something silly, it always has worked for me. So,
34 * with that in mind, I've decided to make this driver look completely like a
35 * stupid Lance from a driver architecture perspective. Only difference is that
36 * here our "ring buffer" looks and acts like a real Lance one does but is
37 * laid out like how the HPC DMA and the Seeq want it to. You'd be surprised
38 * how a stupid idea like this can pay off in performance, not to mention
39 * making this driver 2,000 times easier to write. ;-)
40 */
41
42/* Tune these if we tend to run out often etc. */
43#define SEEQ_RX_BUFFERS 16
44#define SEEQ_TX_BUFFERS 16
45
46#define PKT_BUF_SZ 1584
47
48#define NEXT_RX(i) (((i) + 1) & (SEEQ_RX_BUFFERS - 1))
49#define NEXT_TX(i) (((i) + 1) & (SEEQ_TX_BUFFERS - 1))
50#define PREV_RX(i) (((i) - 1) & (SEEQ_RX_BUFFERS - 1))
51#define PREV_TX(i) (((i) - 1) & (SEEQ_TX_BUFFERS - 1))
52
53#define TX_BUFFS_AVAIL(sp) ((sp->tx_old <= sp->tx_new) ? \
54 sp->tx_old + (SEEQ_TX_BUFFERS - 1) - sp->tx_new : \
55 sp->tx_old - sp->tx_new - 1)
56
57#define VIRT_TO_DMA(sp, v) ((sp)->srings_dma + \
58 (dma_addr_t)((unsigned long)(v) - \
59 (unsigned long)((sp)->rx_desc)))
60
61/* Copy frames shorter than rx_copybreak, otherwise pass on up in
62 * a full sized sk_buff. Value of 100 stolen from tulip.c (!alpha).
63 */
64static int rx_copybreak = 100;
65
66#define PAD_SIZE (128 - sizeof(struct hpc_dma_desc) - sizeof(void *))
67
68struct sgiseeq_rx_desc {
69 volatile struct hpc_dma_desc rdma;
70 u8 padding[PAD_SIZE];
71 struct sk_buff *skb;
72};
73
74struct sgiseeq_tx_desc {
75 volatile struct hpc_dma_desc tdma;
76 u8 padding[PAD_SIZE];
77 struct sk_buff *skb;
78};
79
80/*
81 * Warning: This structure is laid out in a certain way because HPC dma
82 * descriptors must be 8-byte aligned. So don't touch this without
83 * some care.
84 */
85struct sgiseeq_init_block { /* Note the name ;-) */
86 struct sgiseeq_rx_desc rxvector[SEEQ_RX_BUFFERS];
87 struct sgiseeq_tx_desc txvector[SEEQ_TX_BUFFERS];
88};
89
90struct sgiseeq_private {
91 struct sgiseeq_init_block *srings;
92 dma_addr_t srings_dma;
93
94 /* Ptrs to the descriptors in uncached space. */
95 struct sgiseeq_rx_desc *rx_desc;
96 struct sgiseeq_tx_desc *tx_desc;
97
98 char *name;
99 struct hpc3_ethregs *hregs;
100 struct sgiseeq_regs *sregs;
101
102 /* Ring entry counters. */
103 unsigned int rx_new, tx_new;
104 unsigned int rx_old, tx_old;
105
106 int is_edlc;
107 unsigned char control;
108 unsigned char mode;
109
110 spinlock_t tx_lock;
111};
112
113static inline void dma_sync_desc_cpu(struct net_device *dev, void *addr)
114{
115 struct sgiseeq_private *sp = netdev_priv(dev);
116
117 dma_sync_single_for_cpu(dev: dev->dev.parent, VIRT_TO_DMA(sp, addr),
118 size: sizeof(struct sgiseeq_rx_desc), dir: DMA_BIDIRECTIONAL);
119}
120
121static inline void dma_sync_desc_dev(struct net_device *dev, void *addr)
122{
123 struct sgiseeq_private *sp = netdev_priv(dev);
124
125 dma_sync_single_for_device(dev: dev->dev.parent, VIRT_TO_DMA(sp, addr),
126 size: sizeof(struct sgiseeq_rx_desc), dir: DMA_BIDIRECTIONAL);
127}
128
129static inline void hpc3_eth_reset(struct hpc3_ethregs *hregs)
130{
131 hregs->reset = HPC3_ERST_CRESET | HPC3_ERST_CLRIRQ;
132 udelay(20);
133 hregs->reset = 0;
134}
135
136static inline void reset_hpc3_and_seeq(struct hpc3_ethregs *hregs,
137 struct sgiseeq_regs *sregs)
138{
139 hregs->rx_ctrl = hregs->tx_ctrl = 0;
140 hpc3_eth_reset(hregs);
141}
142
143#define RSTAT_GO_BITS (SEEQ_RCMD_IGOOD | SEEQ_RCMD_IEOF | SEEQ_RCMD_ISHORT | \
144 SEEQ_RCMD_IDRIB | SEEQ_RCMD_ICRC)
145
146static inline void seeq_go(struct sgiseeq_private *sp,
147 struct hpc3_ethregs *hregs,
148 struct sgiseeq_regs *sregs)
149{
150 sregs->rstat = sp->mode | RSTAT_GO_BITS;
151 hregs->rx_ctrl = HPC3_ERXCTRL_ACTIVE;
152}
153
154static inline void __sgiseeq_set_mac_address(struct net_device *dev)
155{
156 struct sgiseeq_private *sp = netdev_priv(dev);
157 struct sgiseeq_regs *sregs = sp->sregs;
158 int i;
159
160 sregs->tstat = SEEQ_TCMD_RB0;
161 for (i = 0; i < 6; i++)
162 sregs->rw.eth_addr[i] = dev->dev_addr[i];
163}
164
165static int sgiseeq_set_mac_address(struct net_device *dev, void *addr)
166{
167 struct sgiseeq_private *sp = netdev_priv(dev);
168 struct sockaddr *sa = addr;
169
170 eth_hw_addr_set(dev, addr: sa->sa_data);
171
172 spin_lock_irq(lock: &sp->tx_lock);
173 __sgiseeq_set_mac_address(dev);
174 spin_unlock_irq(lock: &sp->tx_lock);
175
176 return 0;
177}
178
179#define TCNTINFO_INIT (HPCDMA_EOX | HPCDMA_ETXD)
180#define RCNTCFG_INIT (HPCDMA_OWN | HPCDMA_EORP | HPCDMA_XIE)
181#define RCNTINFO_INIT (RCNTCFG_INIT | (PKT_BUF_SZ & HPCDMA_BCNT))
182
183static int seeq_init_ring(struct net_device *dev)
184{
185 struct sgiseeq_private *sp = netdev_priv(dev);
186 int i;
187
188 netif_stop_queue(dev);
189 sp->rx_new = sp->tx_new = 0;
190 sp->rx_old = sp->tx_old = 0;
191
192 __sgiseeq_set_mac_address(dev);
193
194 /* Setup tx ring. */
195 for(i = 0; i < SEEQ_TX_BUFFERS; i++) {
196 sp->tx_desc[i].tdma.cntinfo = TCNTINFO_INIT;
197 dma_sync_desc_dev(dev, addr: &sp->tx_desc[i]);
198 }
199
200 /* And now the rx ring. */
201 for (i = 0; i < SEEQ_RX_BUFFERS; i++) {
202 if (!sp->rx_desc[i].skb) {
203 dma_addr_t dma_addr;
204 struct sk_buff *skb = netdev_alloc_skb(dev, PKT_BUF_SZ);
205
206 if (skb == NULL)
207 return -ENOMEM;
208 skb_reserve(skb, len: 2);
209 dma_addr = dma_map_single(dev->dev.parent,
210 skb->data - 2,
211 PKT_BUF_SZ, DMA_FROM_DEVICE);
212 sp->rx_desc[i].skb = skb;
213 sp->rx_desc[i].rdma.pbuf = dma_addr;
214 }
215 sp->rx_desc[i].rdma.cntinfo = RCNTINFO_INIT;
216 dma_sync_desc_dev(dev, addr: &sp->rx_desc[i]);
217 }
218 sp->rx_desc[i - 1].rdma.cntinfo |= HPCDMA_EOR;
219 dma_sync_desc_dev(dev, addr: &sp->rx_desc[i - 1]);
220 return 0;
221}
222
223static void seeq_purge_ring(struct net_device *dev)
224{
225 struct sgiseeq_private *sp = netdev_priv(dev);
226 int i;
227
228 /* clear tx ring. */
229 for (i = 0; i < SEEQ_TX_BUFFERS; i++) {
230 if (sp->tx_desc[i].skb) {
231 dev_kfree_skb(sp->tx_desc[i].skb);
232 sp->tx_desc[i].skb = NULL;
233 }
234 }
235
236 /* And now the rx ring. */
237 for (i = 0; i < SEEQ_RX_BUFFERS; i++) {
238 if (sp->rx_desc[i].skb) {
239 dev_kfree_skb(sp->rx_desc[i].skb);
240 sp->rx_desc[i].skb = NULL;
241 }
242 }
243}
244
245#ifdef DEBUG
246static struct sgiseeq_private *gpriv;
247static struct net_device *gdev;
248
249static void sgiseeq_dump_rings(void)
250{
251 static int once;
252 struct sgiseeq_rx_desc *r = gpriv->rx_desc;
253 struct sgiseeq_tx_desc *t = gpriv->tx_desc;
254 struct hpc3_ethregs *hregs = gpriv->hregs;
255 int i;
256
257 if (once)
258 return;
259 once++;
260 printk("RING DUMP:\n");
261 for (i = 0; i < SEEQ_RX_BUFFERS; i++) {
262 printk("RX [%d]: @(%p) [%08x,%08x,%08x] ",
263 i, (&r[i]), r[i].rdma.pbuf, r[i].rdma.cntinfo,
264 r[i].rdma.pnext);
265 i += 1;
266 printk("-- [%d]: @(%p) [%08x,%08x,%08x]\n",
267 i, (&r[i]), r[i].rdma.pbuf, r[i].rdma.cntinfo,
268 r[i].rdma.pnext);
269 }
270 for (i = 0; i < SEEQ_TX_BUFFERS; i++) {
271 printk("TX [%d]: @(%p) [%08x,%08x,%08x] ",
272 i, (&t[i]), t[i].tdma.pbuf, t[i].tdma.cntinfo,
273 t[i].tdma.pnext);
274 i += 1;
275 printk("-- [%d]: @(%p) [%08x,%08x,%08x]\n",
276 i, (&t[i]), t[i].tdma.pbuf, t[i].tdma.cntinfo,
277 t[i].tdma.pnext);
278 }
279 printk("INFO: [rx_new = %d rx_old=%d] [tx_new = %d tx_old = %d]\n",
280 gpriv->rx_new, gpriv->rx_old, gpriv->tx_new, gpriv->tx_old);
281 printk("RREGS: rx_cbptr[%08x] rx_ndptr[%08x] rx_ctrl[%08x]\n",
282 hregs->rx_cbptr, hregs->rx_ndptr, hregs->rx_ctrl);
283 printk("TREGS: tx_cbptr[%08x] tx_ndptr[%08x] tx_ctrl[%08x]\n",
284 hregs->tx_cbptr, hregs->tx_ndptr, hregs->tx_ctrl);
285}
286#endif
287
288#define TSTAT_INIT_SEEQ (SEEQ_TCMD_IPT|SEEQ_TCMD_I16|SEEQ_TCMD_IC|SEEQ_TCMD_IUF)
289#define TSTAT_INIT_EDLC ((TSTAT_INIT_SEEQ) | SEEQ_TCMD_RB2)
290
291static int init_seeq(struct net_device *dev, struct sgiseeq_private *sp,
292 struct sgiseeq_regs *sregs)
293{
294 struct hpc3_ethregs *hregs = sp->hregs;
295 int err;
296
297 reset_hpc3_and_seeq(hregs, sregs);
298 err = seeq_init_ring(dev);
299 if (err)
300 return err;
301
302 /* Setup to field the proper interrupt types. */
303 if (sp->is_edlc) {
304 sregs->tstat = TSTAT_INIT_EDLC;
305 sregs->rw.wregs.control = sp->control;
306 sregs->rw.wregs.frame_gap = 0;
307 } else {
308 sregs->tstat = TSTAT_INIT_SEEQ;
309 }
310
311 hregs->rx_ndptr = VIRT_TO_DMA(sp, sp->rx_desc);
312 hregs->tx_ndptr = VIRT_TO_DMA(sp, sp->tx_desc);
313
314 seeq_go(sp, hregs, sregs);
315 return 0;
316}
317
318static void record_rx_errors(struct net_device *dev, unsigned char status)
319{
320 if (status & SEEQ_RSTAT_OVERF ||
321 status & SEEQ_RSTAT_SFRAME)
322 dev->stats.rx_over_errors++;
323 if (status & SEEQ_RSTAT_CERROR)
324 dev->stats.rx_crc_errors++;
325 if (status & SEEQ_RSTAT_DERROR)
326 dev->stats.rx_frame_errors++;
327 if (status & SEEQ_RSTAT_REOF)
328 dev->stats.rx_errors++;
329}
330
331static inline void rx_maybe_restart(struct sgiseeq_private *sp,
332 struct hpc3_ethregs *hregs,
333 struct sgiseeq_regs *sregs)
334{
335 if (!(hregs->rx_ctrl & HPC3_ERXCTRL_ACTIVE)) {
336 hregs->rx_ndptr = VIRT_TO_DMA(sp, sp->rx_desc + sp->rx_new);
337 seeq_go(sp, hregs, sregs);
338 }
339}
340
341static inline void sgiseeq_rx(struct net_device *dev, struct sgiseeq_private *sp,
342 struct hpc3_ethregs *hregs,
343 struct sgiseeq_regs *sregs)
344{
345 struct sgiseeq_rx_desc *rd;
346 struct sk_buff *skb = NULL;
347 struct sk_buff *newskb;
348 unsigned char pkt_status;
349 int len = 0;
350 unsigned int orig_end = PREV_RX(sp->rx_new);
351
352 /* Service every received packet. */
353 rd = &sp->rx_desc[sp->rx_new];
354 dma_sync_desc_cpu(dev, addr: rd);
355 while (!(rd->rdma.cntinfo & HPCDMA_OWN)) {
356 len = PKT_BUF_SZ - (rd->rdma.cntinfo & HPCDMA_BCNT) - 3;
357 dma_unmap_single(dev->dev.parent, rd->rdma.pbuf,
358 PKT_BUF_SZ, DMA_FROM_DEVICE);
359 pkt_status = rd->skb->data[len];
360 if (pkt_status & SEEQ_RSTAT_FIG) {
361 /* Packet is OK. */
362 /* We don't want to receive our own packets */
363 if (!ether_addr_equal(addr1: rd->skb->data + 6, addr2: dev->dev_addr)) {
364 if (len > rx_copybreak) {
365 skb = rd->skb;
366 newskb = netdev_alloc_skb(dev, PKT_BUF_SZ);
367 if (!newskb) {
368 newskb = skb;
369 skb = NULL;
370 goto memory_squeeze;
371 }
372 skb_reserve(skb: newskb, len: 2);
373 } else {
374 skb = netdev_alloc_skb_ip_align(dev, length: len);
375 if (skb)
376 skb_copy_to_linear_data(skb, from: rd->skb->data, len);
377
378 newskb = rd->skb;
379 }
380memory_squeeze:
381 if (skb) {
382 skb_put(skb, len);
383 skb->protocol = eth_type_trans(skb, dev);
384 netif_rx(skb);
385 dev->stats.rx_packets++;
386 dev->stats.rx_bytes += len;
387 } else {
388 dev->stats.rx_dropped++;
389 }
390 } else {
391 /* Silently drop my own packets */
392 newskb = rd->skb;
393 }
394 } else {
395 record_rx_errors(dev, status: pkt_status);
396 newskb = rd->skb;
397 }
398 rd->skb = newskb;
399 rd->rdma.pbuf = dma_map_single(dev->dev.parent,
400 newskb->data - 2,
401 PKT_BUF_SZ, DMA_FROM_DEVICE);
402
403 /* Return the entry to the ring pool. */
404 rd->rdma.cntinfo = RCNTINFO_INIT;
405 sp->rx_new = NEXT_RX(sp->rx_new);
406 dma_sync_desc_dev(dev, addr: rd);
407 rd = &sp->rx_desc[sp->rx_new];
408 dma_sync_desc_cpu(dev, addr: rd);
409 }
410 dma_sync_desc_dev(dev, addr: rd);
411
412 dma_sync_desc_cpu(dev, addr: &sp->rx_desc[orig_end]);
413 sp->rx_desc[orig_end].rdma.cntinfo &= ~(HPCDMA_EOR);
414 dma_sync_desc_dev(dev, addr: &sp->rx_desc[orig_end]);
415 dma_sync_desc_cpu(dev, addr: &sp->rx_desc[PREV_RX(sp->rx_new)]);
416 sp->rx_desc[PREV_RX(sp->rx_new)].rdma.cntinfo |= HPCDMA_EOR;
417 dma_sync_desc_dev(dev, addr: &sp->rx_desc[PREV_RX(sp->rx_new)]);
418 rx_maybe_restart(sp, hregs, sregs);
419}
420
421static inline void tx_maybe_reset_collisions(struct sgiseeq_private *sp,
422 struct sgiseeq_regs *sregs)
423{
424 if (sp->is_edlc) {
425 sregs->rw.wregs.control = sp->control & ~(SEEQ_CTRL_XCNT);
426 sregs->rw.wregs.control = sp->control;
427 }
428}
429
430static inline void kick_tx(struct net_device *dev,
431 struct sgiseeq_private *sp,
432 struct hpc3_ethregs *hregs)
433{
434 struct sgiseeq_tx_desc *td;
435 int i = sp->tx_old;
436
437 /* If the HPC aint doin nothin, and there are more packets
438 * with ETXD cleared and XIU set we must make very certain
439 * that we restart the HPC else we risk locking up the
440 * adapter. The following code is only safe iff the HPCDMA
441 * is not active!
442 */
443 td = &sp->tx_desc[i];
444 dma_sync_desc_cpu(dev, addr: td);
445 while ((td->tdma.cntinfo & (HPCDMA_XIU | HPCDMA_ETXD)) ==
446 (HPCDMA_XIU | HPCDMA_ETXD)) {
447 i = NEXT_TX(i);
448 td = &sp->tx_desc[i];
449 dma_sync_desc_cpu(dev, addr: td);
450 }
451 if (td->tdma.cntinfo & HPCDMA_XIU) {
452 dma_sync_desc_dev(dev, addr: td);
453 hregs->tx_ndptr = VIRT_TO_DMA(sp, td);
454 hregs->tx_ctrl = HPC3_ETXCTRL_ACTIVE;
455 }
456}
457
458static inline void sgiseeq_tx(struct net_device *dev, struct sgiseeq_private *sp,
459 struct hpc3_ethregs *hregs,
460 struct sgiseeq_regs *sregs)
461{
462 struct sgiseeq_tx_desc *td;
463 unsigned long status = hregs->tx_ctrl;
464 int j;
465
466 tx_maybe_reset_collisions(sp, sregs);
467
468 if (!(status & (HPC3_ETXCTRL_ACTIVE | SEEQ_TSTAT_PTRANS))) {
469 /* Oops, HPC detected some sort of error. */
470 if (status & SEEQ_TSTAT_R16)
471 dev->stats.tx_aborted_errors++;
472 if (status & SEEQ_TSTAT_UFLOW)
473 dev->stats.tx_fifo_errors++;
474 if (status & SEEQ_TSTAT_LCLS)
475 dev->stats.collisions++;
476 }
477
478 /* Ack 'em... */
479 for (j = sp->tx_old; j != sp->tx_new; j = NEXT_TX(j)) {
480 td = &sp->tx_desc[j];
481
482 dma_sync_desc_cpu(dev, addr: td);
483 if (!(td->tdma.cntinfo & (HPCDMA_XIU)))
484 break;
485 if (!(td->tdma.cntinfo & (HPCDMA_ETXD))) {
486 dma_sync_desc_dev(dev, addr: td);
487 if (!(status & HPC3_ETXCTRL_ACTIVE)) {
488 hregs->tx_ndptr = VIRT_TO_DMA(sp, td);
489 hregs->tx_ctrl = HPC3_ETXCTRL_ACTIVE;
490 }
491 break;
492 }
493 dev->stats.tx_packets++;
494 sp->tx_old = NEXT_TX(sp->tx_old);
495 td->tdma.cntinfo &= ~(HPCDMA_XIU | HPCDMA_XIE);
496 td->tdma.cntinfo |= HPCDMA_EOX;
497 if (td->skb) {
498 dev_kfree_skb_any(skb: td->skb);
499 td->skb = NULL;
500 }
501 dma_sync_desc_dev(dev, addr: td);
502 }
503}
504
505static irqreturn_t sgiseeq_interrupt(int irq, void *dev_id)
506{
507 struct net_device *dev = (struct net_device *) dev_id;
508 struct sgiseeq_private *sp = netdev_priv(dev);
509 struct hpc3_ethregs *hregs = sp->hregs;
510 struct sgiseeq_regs *sregs = sp->sregs;
511
512 spin_lock(lock: &sp->tx_lock);
513
514 /* Ack the IRQ and set software state. */
515 hregs->reset = HPC3_ERST_CLRIRQ;
516
517 /* Always check for received packets. */
518 sgiseeq_rx(dev, sp, hregs, sregs);
519
520 /* Only check for tx acks if we have something queued. */
521 if (sp->tx_old != sp->tx_new)
522 sgiseeq_tx(dev, sp, hregs, sregs);
523
524 if ((TX_BUFFS_AVAIL(sp) > 0) && netif_queue_stopped(dev)) {
525 netif_wake_queue(dev);
526 }
527 spin_unlock(lock: &sp->tx_lock);
528
529 return IRQ_HANDLED;
530}
531
532static int sgiseeq_open(struct net_device *dev)
533{
534 struct sgiseeq_private *sp = netdev_priv(dev);
535 struct sgiseeq_regs *sregs = sp->sregs;
536 unsigned int irq = dev->irq;
537 int err;
538
539 if (request_irq(irq, handler: sgiseeq_interrupt, flags: 0, name: sgiseeqstr, dev)) {
540 printk(KERN_ERR "Seeq8003: Can't get irq %d\n", dev->irq);
541 return -EAGAIN;
542 }
543
544 err = init_seeq(dev, sp, sregs);
545 if (err)
546 goto out_free_irq;
547
548 netif_start_queue(dev);
549
550 return 0;
551
552out_free_irq:
553 free_irq(irq, dev);
554
555 return err;
556}
557
558static int sgiseeq_close(struct net_device *dev)
559{
560 struct sgiseeq_private *sp = netdev_priv(dev);
561 struct sgiseeq_regs *sregs = sp->sregs;
562 unsigned int irq = dev->irq;
563
564 netif_stop_queue(dev);
565
566 /* Shutdown the Seeq. */
567 reset_hpc3_and_seeq(hregs: sp->hregs, sregs);
568 free_irq(irq, dev);
569 seeq_purge_ring(dev);
570
571 return 0;
572}
573
574static inline int sgiseeq_reset(struct net_device *dev)
575{
576 struct sgiseeq_private *sp = netdev_priv(dev);
577 struct sgiseeq_regs *sregs = sp->sregs;
578 int err;
579
580 err = init_seeq(dev, sp, sregs);
581 if (err)
582 return err;
583
584 netif_trans_update(dev); /* prevent tx timeout */
585 netif_wake_queue(dev);
586
587 return 0;
588}
589
590static netdev_tx_t
591sgiseeq_start_xmit(struct sk_buff *skb, struct net_device *dev)
592{
593 struct sgiseeq_private *sp = netdev_priv(dev);
594 struct hpc3_ethregs *hregs = sp->hregs;
595 unsigned long flags;
596 struct sgiseeq_tx_desc *td;
597 int len, entry;
598
599 spin_lock_irqsave(&sp->tx_lock, flags);
600
601 /* Setup... */
602 len = skb->len;
603 if (len < ETH_ZLEN) {
604 if (skb_padto(skb, ETH_ZLEN)) {
605 spin_unlock_irqrestore(lock: &sp->tx_lock, flags);
606 return NETDEV_TX_OK;
607 }
608 len = ETH_ZLEN;
609 }
610
611 dev->stats.tx_bytes += len;
612 entry = sp->tx_new;
613 td = &sp->tx_desc[entry];
614 dma_sync_desc_cpu(dev, addr: td);
615
616 /* Create entry. There are so many races with adding a new
617 * descriptor to the chain:
618 * 1) Assume that the HPC is off processing a DMA chain while
619 * we are changing all of the following.
620 * 2) Do no allow the HPC to look at a new descriptor until
621 * we have completely set up it's state. This means, do
622 * not clear HPCDMA_EOX in the current last descritptor
623 * until the one we are adding looks consistent and could
624 * be processes right now.
625 * 3) The tx interrupt code must notice when we've added a new
626 * entry and the HPC got to the end of the chain before we
627 * added this new entry and restarted it.
628 */
629 td->skb = skb;
630 td->tdma.pbuf = dma_map_single(dev->dev.parent, skb->data,
631 len, DMA_TO_DEVICE);
632 td->tdma.cntinfo = (len & HPCDMA_BCNT) |
633 HPCDMA_XIU | HPCDMA_EOXP | HPCDMA_XIE | HPCDMA_EOX;
634 dma_sync_desc_dev(dev, addr: td);
635 if (sp->tx_old != sp->tx_new) {
636 struct sgiseeq_tx_desc *backend;
637
638 backend = &sp->tx_desc[PREV_TX(sp->tx_new)];
639 dma_sync_desc_cpu(dev, addr: backend);
640 backend->tdma.cntinfo &= ~HPCDMA_EOX;
641 dma_sync_desc_dev(dev, addr: backend);
642 }
643 sp->tx_new = NEXT_TX(sp->tx_new); /* Advance. */
644
645 /* Maybe kick the HPC back into motion. */
646 if (!(hregs->tx_ctrl & HPC3_ETXCTRL_ACTIVE))
647 kick_tx(dev, sp, hregs);
648
649 if (!TX_BUFFS_AVAIL(sp))
650 netif_stop_queue(dev);
651 spin_unlock_irqrestore(lock: &sp->tx_lock, flags);
652
653 return NETDEV_TX_OK;
654}
655
656static void timeout(struct net_device *dev, unsigned int txqueue)
657{
658 printk(KERN_NOTICE "%s: transmit timed out, resetting\n", dev->name);
659 sgiseeq_reset(dev);
660
661 netif_trans_update(dev); /* prevent tx timeout */
662 netif_wake_queue(dev);
663}
664
665static void sgiseeq_set_multicast(struct net_device *dev)
666{
667 struct sgiseeq_private *sp = netdev_priv(dev);
668 unsigned char oldmode = sp->mode;
669
670 if(dev->flags & IFF_PROMISC)
671 sp->mode = SEEQ_RCMD_RANY;
672 else if ((dev->flags & IFF_ALLMULTI) || !netdev_mc_empty(dev))
673 sp->mode = SEEQ_RCMD_RBMCAST;
674 else
675 sp->mode = SEEQ_RCMD_RBCAST;
676
677 /* XXX I know this sucks, but is there a better way to reprogram
678 * XXX the receiver? At least, this shouldn't happen too often.
679 */
680
681 if (oldmode != sp->mode)
682 sgiseeq_reset(dev);
683}
684
685static inline void setup_tx_ring(struct net_device *dev,
686 struct sgiseeq_tx_desc *buf,
687 int nbufs)
688{
689 struct sgiseeq_private *sp = netdev_priv(dev);
690 int i = 0;
691
692 while (i < (nbufs - 1)) {
693 buf[i].tdma.pnext = VIRT_TO_DMA(sp, buf + i + 1);
694 buf[i].tdma.pbuf = 0;
695 dma_sync_desc_dev(dev, addr: &buf[i]);
696 i++;
697 }
698 buf[i].tdma.pnext = VIRT_TO_DMA(sp, buf);
699 dma_sync_desc_dev(dev, addr: &buf[i]);
700}
701
702static inline void setup_rx_ring(struct net_device *dev,
703 struct sgiseeq_rx_desc *buf,
704 int nbufs)
705{
706 struct sgiseeq_private *sp = netdev_priv(dev);
707 int i = 0;
708
709 while (i < (nbufs - 1)) {
710 buf[i].rdma.pnext = VIRT_TO_DMA(sp, buf + i + 1);
711 buf[i].rdma.pbuf = 0;
712 dma_sync_desc_dev(dev, addr: &buf[i]);
713 i++;
714 }
715 buf[i].rdma.pbuf = 0;
716 buf[i].rdma.pnext = VIRT_TO_DMA(sp, buf);
717 dma_sync_desc_dev(dev, addr: &buf[i]);
718}
719
720static const struct net_device_ops sgiseeq_netdev_ops = {
721 .ndo_open = sgiseeq_open,
722 .ndo_stop = sgiseeq_close,
723 .ndo_start_xmit = sgiseeq_start_xmit,
724 .ndo_tx_timeout = timeout,
725 .ndo_set_rx_mode = sgiseeq_set_multicast,
726 .ndo_set_mac_address = sgiseeq_set_mac_address,
727 .ndo_validate_addr = eth_validate_addr,
728};
729
730static int sgiseeq_probe(struct platform_device *pdev)
731{
732 struct sgiseeq_platform_data *pd = dev_get_platdata(dev: &pdev->dev);
733 struct hpc3_regs *hpcregs = pd->hpc;
734 struct sgiseeq_init_block *sr;
735 unsigned int irq = pd->irq;
736 struct sgiseeq_private *sp;
737 struct net_device *dev;
738 int err;
739
740 dev = alloc_etherdev(sizeof (struct sgiseeq_private));
741 if (!dev) {
742 err = -ENOMEM;
743 goto err_out;
744 }
745
746 platform_set_drvdata(pdev, data: dev);
747 SET_NETDEV_DEV(dev, &pdev->dev);
748 sp = netdev_priv(dev);
749
750 /* Make private data page aligned */
751 sr = dma_alloc_noncoherent(dev: &pdev->dev, size: sizeof(*sp->srings),
752 dma_handle: &sp->srings_dma, dir: DMA_BIDIRECTIONAL, GFP_KERNEL);
753 if (!sr) {
754 printk(KERN_ERR "Sgiseeq: Page alloc failed, aborting.\n");
755 err = -ENOMEM;
756 goto err_out_free_dev;
757 }
758 sp->srings = sr;
759 sp->rx_desc = sp->srings->rxvector;
760 sp->tx_desc = sp->srings->txvector;
761 spin_lock_init(&sp->tx_lock);
762
763 /* A couple calculations now, saves many cycles later. */
764 setup_rx_ring(dev, buf: sp->rx_desc, SEEQ_RX_BUFFERS);
765 setup_tx_ring(dev, buf: sp->tx_desc, SEEQ_TX_BUFFERS);
766
767 eth_hw_addr_set(dev, addr: pd->mac);
768
769#ifdef DEBUG
770 gpriv = sp;
771 gdev = dev;
772#endif
773 sp->sregs = (struct sgiseeq_regs *) &hpcregs->eth_ext[0];
774 sp->hregs = &hpcregs->ethregs;
775 sp->name = sgiseeqstr;
776 sp->mode = SEEQ_RCMD_RBCAST;
777
778 /* Setup PIO and DMA transfer timing */
779 sp->hregs->pconfig = 0x161;
780 sp->hregs->dconfig = HPC3_EDCFG_FIRQ | HPC3_EDCFG_FEOP |
781 HPC3_EDCFG_FRXDC | HPC3_EDCFG_PTO | 0x026;
782
783 /* Setup PIO and DMA transfer timing */
784 sp->hregs->pconfig = 0x161;
785 sp->hregs->dconfig = HPC3_EDCFG_FIRQ | HPC3_EDCFG_FEOP |
786 HPC3_EDCFG_FRXDC | HPC3_EDCFG_PTO | 0x026;
787
788 /* Reset the chip. */
789 hpc3_eth_reset(hregs: sp->hregs);
790
791 sp->is_edlc = !(sp->sregs->rw.rregs.collision_tx[0] & 0xff);
792 if (sp->is_edlc)
793 sp->control = SEEQ_CTRL_XCNT | SEEQ_CTRL_ACCNT |
794 SEEQ_CTRL_SFLAG | SEEQ_CTRL_ESHORT |
795 SEEQ_CTRL_ENCARR;
796
797 dev->netdev_ops = &sgiseeq_netdev_ops;
798 dev->watchdog_timeo = (200 * HZ) / 1000;
799 dev->irq = irq;
800
801 if (register_netdev(dev)) {
802 printk(KERN_ERR "Sgiseeq: Cannot register net device, "
803 "aborting.\n");
804 err = -ENODEV;
805 goto err_out_free_attrs;
806 }
807
808 printk(KERN_INFO "%s: %s %pM\n", dev->name, sgiseeqstr, dev->dev_addr);
809
810 return 0;
811
812err_out_free_attrs:
813 dma_free_noncoherent(dev: &pdev->dev, size: sizeof(*sp->srings), vaddr: sp->srings,
814 dma_handle: sp->srings_dma, dir: DMA_BIDIRECTIONAL);
815err_out_free_dev:
816 free_netdev(dev);
817
818err_out:
819 return err;
820}
821
822static void sgiseeq_remove(struct platform_device *pdev)
823{
824 struct net_device *dev = platform_get_drvdata(pdev);
825 struct sgiseeq_private *sp = netdev_priv(dev);
826
827 unregister_netdev(dev);
828 dma_free_noncoherent(dev: &pdev->dev, size: sizeof(*sp->srings), vaddr: sp->srings,
829 dma_handle: sp->srings_dma, dir: DMA_BIDIRECTIONAL);
830 free_netdev(dev);
831}
832
833static struct platform_driver sgiseeq_driver = {
834 .probe = sgiseeq_probe,
835 .remove_new = sgiseeq_remove,
836 .driver = {
837 .name = "sgiseeq",
838 }
839};
840
841module_platform_driver(sgiseeq_driver);
842
843MODULE_DESCRIPTION("SGI Seeq 8003 driver");
844MODULE_AUTHOR("Linux/MIPS Mailing List <linux-mips@linux-mips.org>");
845MODULE_LICENSE("GPL");
846MODULE_ALIAS("platform:sgiseeq");
847

source code of linux/drivers/net/ethernet/seeq/sgiseeq.c