xref: /openbmc/linux/drivers/net/rionet.c (revision 87c2ce3b)
1 /*
2  * rionet - Ethernet driver over RapidIO messaging services
3  *
4  * Copyright 2005 MontaVista Software, Inc.
5  * Matt Porter <mporter@kernel.crashing.org>
6  *
7  * This program is free software; you can redistribute  it and/or modify it
8  * under  the terms of  the GNU General  Public License as published by the
9  * Free Software Foundation;  either version 2 of the  License, or (at your
10  * option) any later version.
11  */
12 
13 #include <linux/module.h>
14 #include <linux/kernel.h>
15 #include <linux/dma-mapping.h>
16 #include <linux/delay.h>
17 #include <linux/rio.h>
18 #include <linux/rio_drv.h>
19 #include <linux/rio_ids.h>
20 
21 #include <linux/netdevice.h>
22 #include <linux/etherdevice.h>
23 #include <linux/skbuff.h>
24 #include <linux/crc32.h>
25 #include <linux/ethtool.h>
26 
27 #define DRV_NAME        "rionet"
28 #define DRV_VERSION     "0.2"
29 #define DRV_AUTHOR      "Matt Porter <mporter@kernel.crashing.org>"
30 #define DRV_DESC        "Ethernet over RapidIO"
31 
32 MODULE_AUTHOR(DRV_AUTHOR);
33 MODULE_DESCRIPTION(DRV_DESC);
34 MODULE_LICENSE("GPL");
35 
36 #define RIONET_DEFAULT_MSGLEVEL \
37 			(NETIF_MSG_DRV          | \
38 			 NETIF_MSG_LINK         | \
39 			 NETIF_MSG_RX_ERR       | \
40 			 NETIF_MSG_TX_ERR)
41 
42 #define RIONET_DOORBELL_JOIN	0x1000
43 #define RIONET_DOORBELL_LEAVE	0x1001
44 
45 #define RIONET_MAILBOX		0
46 
47 #define RIONET_TX_RING_SIZE	CONFIG_RIONET_TX_SIZE
48 #define RIONET_RX_RING_SIZE	CONFIG_RIONET_RX_SIZE
49 
50 static LIST_HEAD(rionet_peers);
51 
52 struct rionet_private {
53 	struct rio_mport *mport;
54 	struct sk_buff *rx_skb[RIONET_RX_RING_SIZE];
55 	struct sk_buff *tx_skb[RIONET_TX_RING_SIZE];
56 	struct net_device_stats stats;
57 	int rx_slot;
58 	int tx_slot;
59 	int tx_cnt;
60 	int ack_slot;
61 	spinlock_t lock;
62 	spinlock_t tx_lock;
63 	u32 msg_enable;
64 };
65 
66 struct rionet_peer {
67 	struct list_head node;
68 	struct rio_dev *rdev;
69 	struct resource *res;
70 };
71 
72 static int rionet_check = 0;
73 static int rionet_capable = 1;
74 
75 /*
76  * This is a fast lookup table for for translating TX
77  * Ethernet packets into a destination RIO device. It
78  * could be made into a hash table to save memory depending
79  * on system trade-offs.
80  */
81 static struct rio_dev *rionet_active[RIO_MAX_ROUTE_ENTRIES];
82 
83 #define is_rionet_capable(pef, src_ops, dst_ops)		\
84 			((pef & RIO_PEF_INB_MBOX) &&		\
85 			 (pef & RIO_PEF_INB_DOORBELL) &&	\
86 			 (src_ops & RIO_SRC_OPS_DOORBELL) &&	\
87 			 (dst_ops & RIO_DST_OPS_DOORBELL))
88 #define dev_rionet_capable(dev) \
89 	is_rionet_capable(dev->pef, dev->src_ops, dev->dst_ops)
90 
91 #define RIONET_MAC_MATCH(x)	(*(u32 *)x == 0x00010001)
92 #define RIONET_GET_DESTID(x)	(*(u16 *)(x + 4))
93 
94 static struct net_device_stats *rionet_stats(struct net_device *ndev)
95 {
96 	struct rionet_private *rnet = ndev->priv;
97 	return &rnet->stats;
98 }
99 
100 static int rionet_rx_clean(struct net_device *ndev)
101 {
102 	int i;
103 	int error = 0;
104 	struct rionet_private *rnet = ndev->priv;
105 	void *data;
106 
107 	i = rnet->rx_slot;
108 
109 	do {
110 		if (!rnet->rx_skb[i])
111 			continue;
112 
113 		if (!(data = rio_get_inb_message(rnet->mport, RIONET_MAILBOX)))
114 			break;
115 
116 		rnet->rx_skb[i]->data = data;
117 		skb_put(rnet->rx_skb[i], RIO_MAX_MSG_SIZE);
118 		rnet->rx_skb[i]->dev = ndev;
119 		rnet->rx_skb[i]->protocol =
120 		    eth_type_trans(rnet->rx_skb[i], ndev);
121 		error = netif_rx(rnet->rx_skb[i]);
122 
123 		if (error == NET_RX_DROP) {
124 			rnet->stats.rx_dropped++;
125 		} else if (error == NET_RX_BAD) {
126 			if (netif_msg_rx_err(rnet))
127 				printk(KERN_WARNING "%s: bad rx packet\n",
128 				       DRV_NAME);
129 			rnet->stats.rx_errors++;
130 		} else {
131 			rnet->stats.rx_packets++;
132 			rnet->stats.rx_bytes += RIO_MAX_MSG_SIZE;
133 		}
134 
135 	} while ((i = (i + 1) % RIONET_RX_RING_SIZE) != rnet->rx_slot);
136 
137 	return i;
138 }
139 
140 static void rionet_rx_fill(struct net_device *ndev, int end)
141 {
142 	int i;
143 	struct rionet_private *rnet = ndev->priv;
144 
145 	i = rnet->rx_slot;
146 	do {
147 		rnet->rx_skb[i] = dev_alloc_skb(RIO_MAX_MSG_SIZE);
148 
149 		if (!rnet->rx_skb[i])
150 			break;
151 
152 		rio_add_inb_buffer(rnet->mport, RIONET_MAILBOX,
153 				   rnet->rx_skb[i]->data);
154 	} while ((i = (i + 1) % RIONET_RX_RING_SIZE) != end);
155 
156 	rnet->rx_slot = i;
157 }
158 
159 static int rionet_queue_tx_msg(struct sk_buff *skb, struct net_device *ndev,
160 			       struct rio_dev *rdev)
161 {
162 	struct rionet_private *rnet = ndev->priv;
163 
164 	rio_add_outb_message(rnet->mport, rdev, 0, skb->data, skb->len);
165 	rnet->tx_skb[rnet->tx_slot] = skb;
166 
167 	rnet->stats.tx_packets++;
168 	rnet->stats.tx_bytes += skb->len;
169 
170 	if (++rnet->tx_cnt == RIONET_TX_RING_SIZE)
171 		netif_stop_queue(ndev);
172 
173 	++rnet->tx_slot;
174 	rnet->tx_slot &= (RIONET_TX_RING_SIZE - 1);
175 
176 	if (netif_msg_tx_queued(rnet))
177 		printk(KERN_INFO "%s: queued skb %8.8x len %8.8x\n", DRV_NAME,
178 		       (u32) skb, skb->len);
179 
180 	return 0;
181 }
182 
183 static int rionet_start_xmit(struct sk_buff *skb, struct net_device *ndev)
184 {
185 	int i;
186 	struct rionet_private *rnet = ndev->priv;
187 	struct ethhdr *eth = (struct ethhdr *)skb->data;
188 	u16 destid;
189 	unsigned long flags;
190 
191 	local_irq_save(flags);
192 	if (!spin_trylock(&rnet->tx_lock)) {
193 		local_irq_restore(flags);
194 		return NETDEV_TX_LOCKED;
195 	}
196 
197 	if ((rnet->tx_cnt + 1) > RIONET_TX_RING_SIZE) {
198 		netif_stop_queue(ndev);
199 		spin_unlock_irqrestore(&rnet->tx_lock, flags);
200 		printk(KERN_ERR "%s: BUG! Tx Ring full when queue awake!\n",
201 		       ndev->name);
202 		return NETDEV_TX_BUSY;
203 	}
204 
205 	if (eth->h_dest[0] & 0x01) {
206 		for (i = 0; i < RIO_MAX_ROUTE_ENTRIES; i++)
207 			if (rionet_active[i])
208 				rionet_queue_tx_msg(skb, ndev,
209 						    rionet_active[i]);
210 	} else if (RIONET_MAC_MATCH(eth->h_dest)) {
211 		destid = RIONET_GET_DESTID(eth->h_dest);
212 		if (rionet_active[destid])
213 			rionet_queue_tx_msg(skb, ndev, rionet_active[destid]);
214 	}
215 
216 	spin_unlock_irqrestore(&rnet->tx_lock, flags);
217 
218 	return 0;
219 }
220 
221 static void rionet_dbell_event(struct rio_mport *mport, void *dev_id, u16 sid, u16 tid,
222 			       u16 info)
223 {
224 	struct net_device *ndev = dev_id;
225 	struct rionet_private *rnet = ndev->priv;
226 	struct rionet_peer *peer;
227 
228 	if (netif_msg_intr(rnet))
229 		printk(KERN_INFO "%s: doorbell sid %4.4x tid %4.4x info %4.4x",
230 		       DRV_NAME, sid, tid, info);
231 	if (info == RIONET_DOORBELL_JOIN) {
232 		if (!rionet_active[sid]) {
233 			list_for_each_entry(peer, &rionet_peers, node) {
234 				if (peer->rdev->destid == sid)
235 					rionet_active[sid] = peer->rdev;
236 			}
237 			rio_mport_send_doorbell(mport, sid,
238 						RIONET_DOORBELL_JOIN);
239 		}
240 	} else if (info == RIONET_DOORBELL_LEAVE) {
241 		rionet_active[sid] = NULL;
242 	} else {
243 		if (netif_msg_intr(rnet))
244 			printk(KERN_WARNING "%s: unhandled doorbell\n",
245 			       DRV_NAME);
246 	}
247 }
248 
249 static void rionet_inb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
250 {
251 	int n;
252 	struct net_device *ndev = dev_id;
253 	struct rionet_private *rnet = (struct rionet_private *)ndev->priv;
254 
255 	if (netif_msg_intr(rnet))
256 		printk(KERN_INFO "%s: inbound message event, mbox %d slot %d\n",
257 		       DRV_NAME, mbox, slot);
258 
259 	spin_lock(&rnet->lock);
260 	if ((n = rionet_rx_clean(ndev)) != rnet->rx_slot)
261 		rionet_rx_fill(ndev, n);
262 	spin_unlock(&rnet->lock);
263 }
264 
265 static void rionet_outb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
266 {
267 	struct net_device *ndev = dev_id;
268 	struct rionet_private *rnet = ndev->priv;
269 
270 	spin_lock(&rnet->lock);
271 
272 	if (netif_msg_intr(rnet))
273 		printk(KERN_INFO
274 		       "%s: outbound message event, mbox %d slot %d\n",
275 		       DRV_NAME, mbox, slot);
276 
277 	while (rnet->tx_cnt && (rnet->ack_slot != slot)) {
278 		/* dma unmap single */
279 		dev_kfree_skb_irq(rnet->tx_skb[rnet->ack_slot]);
280 		rnet->tx_skb[rnet->ack_slot] = NULL;
281 		++rnet->ack_slot;
282 		rnet->ack_slot &= (RIONET_TX_RING_SIZE - 1);
283 		rnet->tx_cnt--;
284 	}
285 
286 	if (rnet->tx_cnt < RIONET_TX_RING_SIZE)
287 		netif_wake_queue(ndev);
288 
289 	spin_unlock(&rnet->lock);
290 }
291 
292 static int rionet_open(struct net_device *ndev)
293 {
294 	int i, rc = 0;
295 	struct rionet_peer *peer, *tmp;
296 	u32 pwdcsr;
297 	struct rionet_private *rnet = ndev->priv;
298 
299 	if (netif_msg_ifup(rnet))
300 		printk(KERN_INFO "%s: open\n", DRV_NAME);
301 
302 	if ((rc = rio_request_inb_dbell(rnet->mport,
303 					(void *)ndev,
304 					RIONET_DOORBELL_JOIN,
305 					RIONET_DOORBELL_LEAVE,
306 					rionet_dbell_event)) < 0)
307 		goto out;
308 
309 	if ((rc = rio_request_inb_mbox(rnet->mport,
310 				       (void *)ndev,
311 				       RIONET_MAILBOX,
312 				       RIONET_RX_RING_SIZE,
313 				       rionet_inb_msg_event)) < 0)
314 		goto out;
315 
316 	if ((rc = rio_request_outb_mbox(rnet->mport,
317 					(void *)ndev,
318 					RIONET_MAILBOX,
319 					RIONET_TX_RING_SIZE,
320 					rionet_outb_msg_event)) < 0)
321 		goto out;
322 
323 	/* Initialize inbound message ring */
324 	for (i = 0; i < RIONET_RX_RING_SIZE; i++)
325 		rnet->rx_skb[i] = NULL;
326 	rnet->rx_slot = 0;
327 	rionet_rx_fill(ndev, 0);
328 
329 	rnet->tx_slot = 0;
330 	rnet->tx_cnt = 0;
331 	rnet->ack_slot = 0;
332 
333 	netif_carrier_on(ndev);
334 	netif_start_queue(ndev);
335 
336 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
337 		if (!(peer->res = rio_request_outb_dbell(peer->rdev,
338 							 RIONET_DOORBELL_JOIN,
339 							 RIONET_DOORBELL_LEAVE)))
340 		{
341 			printk(KERN_ERR "%s: error requesting doorbells\n",
342 			       DRV_NAME);
343 			continue;
344 		}
345 
346 		/*
347 		 * If device has initialized inbound doorbells,
348 		 * send a join message
349 		 */
350 		rio_read_config_32(peer->rdev, RIO_WRITE_PORT_CSR, &pwdcsr);
351 		if (pwdcsr & RIO_DOORBELL_AVAIL)
352 			rio_send_doorbell(peer->rdev, RIONET_DOORBELL_JOIN);
353 	}
354 
355       out:
356 	return rc;
357 }
358 
359 static int rionet_close(struct net_device *ndev)
360 {
361 	struct rionet_private *rnet = (struct rionet_private *)ndev->priv;
362 	struct rionet_peer *peer, *tmp;
363 	int i;
364 
365 	if (netif_msg_ifup(rnet))
366 		printk(KERN_INFO "%s: close\n", DRV_NAME);
367 
368 	netif_stop_queue(ndev);
369 	netif_carrier_off(ndev);
370 
371 	for (i = 0; i < RIONET_RX_RING_SIZE; i++)
372 		if (rnet->rx_skb[i])
373 			kfree_skb(rnet->rx_skb[i]);
374 
375 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
376 		if (rionet_active[peer->rdev->destid]) {
377 			rio_send_doorbell(peer->rdev, RIONET_DOORBELL_LEAVE);
378 			rionet_active[peer->rdev->destid] = NULL;
379 		}
380 		rio_release_outb_dbell(peer->rdev, peer->res);
381 	}
382 
383 	rio_release_inb_dbell(rnet->mport, RIONET_DOORBELL_JOIN,
384 			      RIONET_DOORBELL_LEAVE);
385 	rio_release_inb_mbox(rnet->mport, RIONET_MAILBOX);
386 	rio_release_outb_mbox(rnet->mport, RIONET_MAILBOX);
387 
388 	return 0;
389 }
390 
391 static void rionet_remove(struct rio_dev *rdev)
392 {
393 	struct net_device *ndev = NULL;
394 	struct rionet_peer *peer, *tmp;
395 
396 	unregister_netdev(ndev);
397 	kfree(ndev);
398 
399 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
400 		list_del(&peer->node);
401 		kfree(peer);
402 	}
403 }
404 
405 static void rionet_get_drvinfo(struct net_device *ndev,
406 			       struct ethtool_drvinfo *info)
407 {
408 	struct rionet_private *rnet = ndev->priv;
409 
410 	strcpy(info->driver, DRV_NAME);
411 	strcpy(info->version, DRV_VERSION);
412 	strcpy(info->fw_version, "n/a");
413 	strcpy(info->bus_info, rnet->mport->name);
414 }
415 
416 static u32 rionet_get_msglevel(struct net_device *ndev)
417 {
418 	struct rionet_private *rnet = ndev->priv;
419 
420 	return rnet->msg_enable;
421 }
422 
423 static void rionet_set_msglevel(struct net_device *ndev, u32 value)
424 {
425 	struct rionet_private *rnet = ndev->priv;
426 
427 	rnet->msg_enable = value;
428 }
429 
430 static struct ethtool_ops rionet_ethtool_ops = {
431 	.get_drvinfo = rionet_get_drvinfo,
432 	.get_msglevel = rionet_get_msglevel,
433 	.set_msglevel = rionet_set_msglevel,
434 	.get_link = ethtool_op_get_link,
435 };
436 
437 static int rionet_setup_netdev(struct rio_mport *mport)
438 {
439 	int rc = 0;
440 	struct net_device *ndev = NULL;
441 	struct rionet_private *rnet;
442 	u16 device_id;
443 
444 	/* Allocate our net_device structure */
445 	ndev = alloc_etherdev(sizeof(struct rionet_private));
446 	if (ndev == NULL) {
447 		printk(KERN_INFO "%s: could not allocate ethernet device.\n",
448 		       DRV_NAME);
449 		rc = -ENOMEM;
450 		goto out;
451 	}
452 
453 	/* Set up private area */
454 	rnet = (struct rionet_private *)ndev->priv;
455 	rnet->mport = mport;
456 
457 	/* Set the default MAC address */
458 	device_id = rio_local_get_device_id(mport);
459 	ndev->dev_addr[0] = 0x00;
460 	ndev->dev_addr[1] = 0x01;
461 	ndev->dev_addr[2] = 0x00;
462 	ndev->dev_addr[3] = 0x01;
463 	ndev->dev_addr[4] = device_id >> 8;
464 	ndev->dev_addr[5] = device_id & 0xff;
465 
466 	/* Fill in the driver function table */
467 	ndev->open = &rionet_open;
468 	ndev->hard_start_xmit = &rionet_start_xmit;
469 	ndev->stop = &rionet_close;
470 	ndev->get_stats = &rionet_stats;
471 	ndev->mtu = RIO_MAX_MSG_SIZE - 14;
472 	ndev->features = NETIF_F_LLTX;
473 	SET_ETHTOOL_OPS(ndev, &rionet_ethtool_ops);
474 
475 	SET_MODULE_OWNER(ndev);
476 
477 	spin_lock_init(&rnet->lock);
478 	spin_lock_init(&rnet->tx_lock);
479 
480 	rnet->msg_enable = RIONET_DEFAULT_MSGLEVEL;
481 
482 	rc = register_netdev(ndev);
483 	if (rc != 0)
484 		goto out;
485 
486 	printk("%s: %s %s Version %s, MAC %02x:%02x:%02x:%02x:%02x:%02x\n",
487 	       ndev->name,
488 	       DRV_NAME,
489 	       DRV_DESC,
490 	       DRV_VERSION,
491 	       ndev->dev_addr[0], ndev->dev_addr[1], ndev->dev_addr[2],
492 	       ndev->dev_addr[3], ndev->dev_addr[4], ndev->dev_addr[5]);
493 
494       out:
495 	return rc;
496 }
497 
498 /*
499  * XXX Make multi-net safe
500  */
501 static int rionet_probe(struct rio_dev *rdev, const struct rio_device_id *id)
502 {
503 	int rc = -ENODEV;
504 	u32 lpef, lsrc_ops, ldst_ops;
505 	struct rionet_peer *peer;
506 
507 	/* If local device is not rionet capable, give up quickly */
508 	if (!rionet_capable)
509 		goto out;
510 
511 	/*
512 	 * First time through, make sure local device is rionet
513 	 * capable, setup netdev,  and set flags so this is skipped
514 	 * on later probes
515 	 */
516 	if (!rionet_check) {
517 		rio_local_read_config_32(rdev->net->hport, RIO_PEF_CAR, &lpef);
518 		rio_local_read_config_32(rdev->net->hport, RIO_SRC_OPS_CAR,
519 					 &lsrc_ops);
520 		rio_local_read_config_32(rdev->net->hport, RIO_DST_OPS_CAR,
521 					 &ldst_ops);
522 		if (!is_rionet_capable(lpef, lsrc_ops, ldst_ops)) {
523 			printk(KERN_ERR
524 			       "%s: local device is not network capable\n",
525 			       DRV_NAME);
526 			rionet_check = 1;
527 			rionet_capable = 0;
528 			goto out;
529 		}
530 
531 		rc = rionet_setup_netdev(rdev->net->hport);
532 		rionet_check = 1;
533 	}
534 
535 	/*
536 	 * If the remote device has mailbox/doorbell capabilities,
537 	 * add it to the peer list.
538 	 */
539 	if (dev_rionet_capable(rdev)) {
540 		if (!(peer = kmalloc(sizeof(struct rionet_peer), GFP_KERNEL))) {
541 			rc = -ENOMEM;
542 			goto out;
543 		}
544 		peer->rdev = rdev;
545 		list_add_tail(&peer->node, &rionet_peers);
546 	}
547 
548       out:
549 	return rc;
550 }
551 
552 static struct rio_device_id rionet_id_table[] = {
553 	{RIO_DEVICE(RIO_ANY_ID, RIO_ANY_ID)}
554 };
555 
556 static struct rio_driver rionet_driver = {
557 	.name = "rionet",
558 	.id_table = rionet_id_table,
559 	.probe = rionet_probe,
560 	.remove = rionet_remove,
561 };
562 
563 static int __init rionet_init(void)
564 {
565 	return rio_register_driver(&rionet_driver);
566 }
567 
568 static void __exit rionet_exit(void)
569 {
570 	rio_unregister_driver(&rionet_driver);
571 }
572 
573 module_init(rionet_init);
574 module_exit(rionet_exit);
575