xref: /linux/drivers/net/rionet.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
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/slab.h>
20 #include <linux/rio_ids.h>
21 
22 #include <linux/netdevice.h>
23 #include <linux/etherdevice.h>
24 #include <linux/skbuff.h>
25 #include <linux/crc32.h>
26 #include <linux/ethtool.h>
27 
28 #define DRV_NAME        "rionet"
29 #define DRV_VERSION     "0.2"
30 #define DRV_AUTHOR      "Matt Porter <mporter@kernel.crashing.org>"
31 #define DRV_DESC        "Ethernet over RapidIO"
32 
33 MODULE_AUTHOR(DRV_AUTHOR);
34 MODULE_DESCRIPTION(DRV_DESC);
35 MODULE_LICENSE("GPL");
36 
37 #define RIONET_DEFAULT_MSGLEVEL \
38 			(NETIF_MSG_DRV          | \
39 			 NETIF_MSG_LINK         | \
40 			 NETIF_MSG_RX_ERR       | \
41 			 NETIF_MSG_TX_ERR)
42 
43 #define RIONET_DOORBELL_JOIN	0x1000
44 #define RIONET_DOORBELL_LEAVE	0x1001
45 
46 #define RIONET_MAILBOX		0
47 
48 #define RIONET_TX_RING_SIZE	CONFIG_RIONET_TX_SIZE
49 #define RIONET_RX_RING_SIZE	CONFIG_RIONET_RX_SIZE
50 
51 static LIST_HEAD(rionet_peers);
52 
53 struct rionet_private {
54 	struct rio_mport *mport;
55 	struct sk_buff *rx_skb[RIONET_RX_RING_SIZE];
56 	struct sk_buff *tx_skb[RIONET_TX_RING_SIZE];
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 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;
82 
83 #define is_rionet_capable(src_ops, dst_ops)			\
84 			((src_ops & RIO_SRC_OPS_DATA_MSG) &&	\
85 			 (dst_ops & RIO_DST_OPS_DATA_MSG) &&	\
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->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 int rionet_rx_clean(struct net_device *ndev)
95 {
96 	int i;
97 	int error = 0;
98 	struct rionet_private *rnet = netdev_priv(ndev);
99 	void *data;
100 
101 	i = rnet->rx_slot;
102 
103 	do {
104 		if (!rnet->rx_skb[i])
105 			continue;
106 
107 		if (!(data = rio_get_inb_message(rnet->mport, RIONET_MAILBOX)))
108 			break;
109 
110 		rnet->rx_skb[i]->data = data;
111 		skb_put(rnet->rx_skb[i], RIO_MAX_MSG_SIZE);
112 		rnet->rx_skb[i]->protocol =
113 		    eth_type_trans(rnet->rx_skb[i], ndev);
114 		error = netif_rx(rnet->rx_skb[i]);
115 
116 		if (error == NET_RX_DROP) {
117 			ndev->stats.rx_dropped++;
118 		} else {
119 			ndev->stats.rx_packets++;
120 			ndev->stats.rx_bytes += RIO_MAX_MSG_SIZE;
121 		}
122 
123 	} while ((i = (i + 1) % RIONET_RX_RING_SIZE) != rnet->rx_slot);
124 
125 	return i;
126 }
127 
128 static void rionet_rx_fill(struct net_device *ndev, int end)
129 {
130 	int i;
131 	struct rionet_private *rnet = netdev_priv(ndev);
132 
133 	i = rnet->rx_slot;
134 	do {
135 		rnet->rx_skb[i] = dev_alloc_skb(RIO_MAX_MSG_SIZE);
136 
137 		if (!rnet->rx_skb[i])
138 			break;
139 
140 		rio_add_inb_buffer(rnet->mport, RIONET_MAILBOX,
141 				   rnet->rx_skb[i]->data);
142 	} while ((i = (i + 1) % RIONET_RX_RING_SIZE) != end);
143 
144 	rnet->rx_slot = i;
145 }
146 
147 static int rionet_queue_tx_msg(struct sk_buff *skb, struct net_device *ndev,
148 			       struct rio_dev *rdev)
149 {
150 	struct rionet_private *rnet = netdev_priv(ndev);
151 
152 	rio_add_outb_message(rnet->mport, rdev, 0, skb->data, skb->len);
153 	rnet->tx_skb[rnet->tx_slot] = skb;
154 
155 	ndev->stats.tx_packets++;
156 	ndev->stats.tx_bytes += skb->len;
157 
158 	if (++rnet->tx_cnt == RIONET_TX_RING_SIZE)
159 		netif_stop_queue(ndev);
160 
161 	++rnet->tx_slot;
162 	rnet->tx_slot &= (RIONET_TX_RING_SIZE - 1);
163 
164 	if (netif_msg_tx_queued(rnet))
165 		printk(KERN_INFO "%s: queued skb len %8.8x\n", DRV_NAME,
166 		       skb->len);
167 
168 	return 0;
169 }
170 
171 static int rionet_start_xmit(struct sk_buff *skb, struct net_device *ndev)
172 {
173 	int i;
174 	struct rionet_private *rnet = netdev_priv(ndev);
175 	struct ethhdr *eth = (struct ethhdr *)skb->data;
176 	u16 destid;
177 	unsigned long flags;
178 
179 	local_irq_save(flags);
180 	if (!spin_trylock(&rnet->tx_lock)) {
181 		local_irq_restore(flags);
182 		return NETDEV_TX_LOCKED;
183 	}
184 
185 	if ((rnet->tx_cnt + 1) > RIONET_TX_RING_SIZE) {
186 		netif_stop_queue(ndev);
187 		spin_unlock_irqrestore(&rnet->tx_lock, flags);
188 		printk(KERN_ERR "%s: BUG! Tx Ring full when queue awake!\n",
189 		       ndev->name);
190 		return NETDEV_TX_BUSY;
191 	}
192 
193 	if (is_multicast_ether_addr(eth->h_dest)) {
194 		for (i = 0; i < RIO_MAX_ROUTE_ENTRIES(rnet->mport->sys_size);
195 				i++)
196 			if (rionet_active[i])
197 				rionet_queue_tx_msg(skb, ndev,
198 						    rionet_active[i]);
199 	} else if (RIONET_MAC_MATCH(eth->h_dest)) {
200 		destid = RIONET_GET_DESTID(eth->h_dest);
201 		if (rionet_active[destid])
202 			rionet_queue_tx_msg(skb, ndev, rionet_active[destid]);
203 	}
204 
205 	spin_unlock_irqrestore(&rnet->tx_lock, flags);
206 
207 	return NETDEV_TX_OK;
208 }
209 
210 static void rionet_dbell_event(struct rio_mport *mport, void *dev_id, u16 sid, u16 tid,
211 			       u16 info)
212 {
213 	struct net_device *ndev = dev_id;
214 	struct rionet_private *rnet = netdev_priv(ndev);
215 	struct rionet_peer *peer;
216 
217 	if (netif_msg_intr(rnet))
218 		printk(KERN_INFO "%s: doorbell sid %4.4x tid %4.4x info %4.4x",
219 		       DRV_NAME, sid, tid, info);
220 	if (info == RIONET_DOORBELL_JOIN) {
221 		if (!rionet_active[sid]) {
222 			list_for_each_entry(peer, &rionet_peers, node) {
223 				if (peer->rdev->destid == sid)
224 					rionet_active[sid] = peer->rdev;
225 			}
226 			rio_mport_send_doorbell(mport, sid,
227 						RIONET_DOORBELL_JOIN);
228 		}
229 	} else if (info == RIONET_DOORBELL_LEAVE) {
230 		rionet_active[sid] = NULL;
231 	} else {
232 		if (netif_msg_intr(rnet))
233 			printk(KERN_WARNING "%s: unhandled doorbell\n",
234 			       DRV_NAME);
235 	}
236 }
237 
238 static void rionet_inb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
239 {
240 	int n;
241 	struct net_device *ndev = dev_id;
242 	struct rionet_private *rnet = netdev_priv(ndev);
243 
244 	if (netif_msg_intr(rnet))
245 		printk(KERN_INFO "%s: inbound message event, mbox %d slot %d\n",
246 		       DRV_NAME, mbox, slot);
247 
248 	spin_lock(&rnet->lock);
249 	if ((n = rionet_rx_clean(ndev)) != rnet->rx_slot)
250 		rionet_rx_fill(ndev, n);
251 	spin_unlock(&rnet->lock);
252 }
253 
254 static void rionet_outb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
255 {
256 	struct net_device *ndev = dev_id;
257 	struct rionet_private *rnet = netdev_priv(ndev);
258 
259 	spin_lock(&rnet->lock);
260 
261 	if (netif_msg_intr(rnet))
262 		printk(KERN_INFO
263 		       "%s: outbound message event, mbox %d slot %d\n",
264 		       DRV_NAME, mbox, slot);
265 
266 	while (rnet->tx_cnt && (rnet->ack_slot != slot)) {
267 		/* dma unmap single */
268 		dev_kfree_skb_irq(rnet->tx_skb[rnet->ack_slot]);
269 		rnet->tx_skb[rnet->ack_slot] = NULL;
270 		++rnet->ack_slot;
271 		rnet->ack_slot &= (RIONET_TX_RING_SIZE - 1);
272 		rnet->tx_cnt--;
273 	}
274 
275 	if (rnet->tx_cnt < RIONET_TX_RING_SIZE)
276 		netif_wake_queue(ndev);
277 
278 	spin_unlock(&rnet->lock);
279 }
280 
281 static int rionet_open(struct net_device *ndev)
282 {
283 	int i, rc = 0;
284 	struct rionet_peer *peer, *tmp;
285 	struct rionet_private *rnet = netdev_priv(ndev);
286 
287 	if (netif_msg_ifup(rnet))
288 		printk(KERN_INFO "%s: open\n", DRV_NAME);
289 
290 	if ((rc = rio_request_inb_dbell(rnet->mport,
291 					(void *)ndev,
292 					RIONET_DOORBELL_JOIN,
293 					RIONET_DOORBELL_LEAVE,
294 					rionet_dbell_event)) < 0)
295 		goto out;
296 
297 	if ((rc = rio_request_inb_mbox(rnet->mport,
298 				       (void *)ndev,
299 				       RIONET_MAILBOX,
300 				       RIONET_RX_RING_SIZE,
301 				       rionet_inb_msg_event)) < 0)
302 		goto out;
303 
304 	if ((rc = rio_request_outb_mbox(rnet->mport,
305 					(void *)ndev,
306 					RIONET_MAILBOX,
307 					RIONET_TX_RING_SIZE,
308 					rionet_outb_msg_event)) < 0)
309 		goto out;
310 
311 	/* Initialize inbound message ring */
312 	for (i = 0; i < RIONET_RX_RING_SIZE; i++)
313 		rnet->rx_skb[i] = NULL;
314 	rnet->rx_slot = 0;
315 	rionet_rx_fill(ndev, 0);
316 
317 	rnet->tx_slot = 0;
318 	rnet->tx_cnt = 0;
319 	rnet->ack_slot = 0;
320 
321 	netif_carrier_on(ndev);
322 	netif_start_queue(ndev);
323 
324 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
325 		if (!(peer->res = rio_request_outb_dbell(peer->rdev,
326 							 RIONET_DOORBELL_JOIN,
327 							 RIONET_DOORBELL_LEAVE)))
328 		{
329 			printk(KERN_ERR "%s: error requesting doorbells\n",
330 			       DRV_NAME);
331 			continue;
332 		}
333 
334 		/* Send a join message */
335 		rio_send_doorbell(peer->rdev, RIONET_DOORBELL_JOIN);
336 	}
337 
338       out:
339 	return rc;
340 }
341 
342 static int rionet_close(struct net_device *ndev)
343 {
344 	struct rionet_private *rnet = netdev_priv(ndev);
345 	struct rionet_peer *peer, *tmp;
346 	int i;
347 
348 	if (netif_msg_ifup(rnet))
349 		printk(KERN_INFO "%s: close\n", DRV_NAME);
350 
351 	netif_stop_queue(ndev);
352 	netif_carrier_off(ndev);
353 
354 	for (i = 0; i < RIONET_RX_RING_SIZE; i++)
355 		kfree_skb(rnet->rx_skb[i]);
356 
357 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
358 		if (rionet_active[peer->rdev->destid]) {
359 			rio_send_doorbell(peer->rdev, RIONET_DOORBELL_LEAVE);
360 			rionet_active[peer->rdev->destid] = NULL;
361 		}
362 		rio_release_outb_dbell(peer->rdev, peer->res);
363 	}
364 
365 	rio_release_inb_dbell(rnet->mport, RIONET_DOORBELL_JOIN,
366 			      RIONET_DOORBELL_LEAVE);
367 	rio_release_inb_mbox(rnet->mport, RIONET_MAILBOX);
368 	rio_release_outb_mbox(rnet->mport, RIONET_MAILBOX);
369 
370 	return 0;
371 }
372 
373 static void rionet_remove(struct rio_dev *rdev)
374 {
375 	struct net_device *ndev = rio_get_drvdata(rdev);
376 	struct rionet_peer *peer, *tmp;
377 
378 	free_pages((unsigned long)rionet_active, rdev->net->hport->sys_size ?
379 					__fls(sizeof(void *)) + 4 : 0);
380 	unregister_netdev(ndev);
381 	free_netdev(ndev);
382 
383 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
384 		list_del(&peer->node);
385 		kfree(peer);
386 	}
387 }
388 
389 static void rionet_get_drvinfo(struct net_device *ndev,
390 			       struct ethtool_drvinfo *info)
391 {
392 	struct rionet_private *rnet = netdev_priv(ndev);
393 
394 	strcpy(info->driver, DRV_NAME);
395 	strcpy(info->version, DRV_VERSION);
396 	strcpy(info->fw_version, "n/a");
397 	strcpy(info->bus_info, rnet->mport->name);
398 }
399 
400 static u32 rionet_get_msglevel(struct net_device *ndev)
401 {
402 	struct rionet_private *rnet = netdev_priv(ndev);
403 
404 	return rnet->msg_enable;
405 }
406 
407 static void rionet_set_msglevel(struct net_device *ndev, u32 value)
408 {
409 	struct rionet_private *rnet = netdev_priv(ndev);
410 
411 	rnet->msg_enable = value;
412 }
413 
414 static const struct ethtool_ops rionet_ethtool_ops = {
415 	.get_drvinfo = rionet_get_drvinfo,
416 	.get_msglevel = rionet_get_msglevel,
417 	.set_msglevel = rionet_set_msglevel,
418 	.get_link = ethtool_op_get_link,
419 };
420 
421 static const struct net_device_ops rionet_netdev_ops = {
422 	.ndo_open		= rionet_open,
423 	.ndo_stop		= rionet_close,
424 	.ndo_start_xmit		= rionet_start_xmit,
425 	.ndo_change_mtu		= eth_change_mtu,
426 	.ndo_validate_addr	= eth_validate_addr,
427 	.ndo_set_mac_address	= eth_mac_addr,
428 };
429 
430 static int rionet_setup_netdev(struct rio_mport *mport, struct net_device *ndev)
431 {
432 	int rc = 0;
433 	struct rionet_private *rnet;
434 	u16 device_id;
435 
436 	rionet_active = (struct rio_dev **)__get_free_pages(GFP_KERNEL,
437 			mport->sys_size ? __fls(sizeof(void *)) + 4 : 0);
438 	if (!rionet_active) {
439 		rc = -ENOMEM;
440 		goto out;
441 	}
442 	memset((void *)rionet_active, 0, sizeof(void *) *
443 				RIO_MAX_ROUTE_ENTRIES(mport->sys_size));
444 
445 	/* Set up private area */
446 	rnet = netdev_priv(ndev);
447 	rnet->mport = mport;
448 
449 	/* Set the default MAC address */
450 	device_id = rio_local_get_device_id(mport);
451 	ndev->dev_addr[0] = 0x00;
452 	ndev->dev_addr[1] = 0x01;
453 	ndev->dev_addr[2] = 0x00;
454 	ndev->dev_addr[3] = 0x01;
455 	ndev->dev_addr[4] = device_id >> 8;
456 	ndev->dev_addr[5] = device_id & 0xff;
457 
458 	ndev->netdev_ops = &rionet_netdev_ops;
459 	ndev->mtu = RIO_MAX_MSG_SIZE - 14;
460 	ndev->features = NETIF_F_LLTX;
461 	SET_ETHTOOL_OPS(ndev, &rionet_ethtool_ops);
462 
463 	spin_lock_init(&rnet->lock);
464 	spin_lock_init(&rnet->tx_lock);
465 
466 	rnet->msg_enable = RIONET_DEFAULT_MSGLEVEL;
467 
468 	rc = register_netdev(ndev);
469 	if (rc != 0)
470 		goto out;
471 
472 	printk("%s: %s %s Version %s, MAC %pM\n",
473 	       ndev->name,
474 	       DRV_NAME,
475 	       DRV_DESC,
476 	       DRV_VERSION,
477 	       ndev->dev_addr);
478 
479       out:
480 	return rc;
481 }
482 
483 /*
484  * XXX Make multi-net safe
485  */
486 static int rionet_probe(struct rio_dev *rdev, const struct rio_device_id *id)
487 {
488 	int rc = -ENODEV;
489 	u32 lsrc_ops, ldst_ops;
490 	struct rionet_peer *peer;
491 	struct net_device *ndev = NULL;
492 
493 	/* If local device is not rionet capable, give up quickly */
494 	if (!rionet_capable)
495 		goto out;
496 
497 	/* Allocate our net_device structure */
498 	ndev = alloc_etherdev(sizeof(struct rionet_private));
499 	if (ndev == NULL) {
500 		printk(KERN_INFO "%s: could not allocate ethernet device.\n",
501 		       DRV_NAME);
502 		rc = -ENOMEM;
503 		goto out;
504 	}
505 
506 	/*
507 	 * First time through, make sure local device is rionet
508 	 * capable, setup netdev,  and set flags so this is skipped
509 	 * on later probes
510 	 */
511 	if (!rionet_check) {
512 		rio_local_read_config_32(rdev->net->hport, RIO_SRC_OPS_CAR,
513 					 &lsrc_ops);
514 		rio_local_read_config_32(rdev->net->hport, RIO_DST_OPS_CAR,
515 					 &ldst_ops);
516 		if (!is_rionet_capable(lsrc_ops, ldst_ops)) {
517 			printk(KERN_ERR
518 			       "%s: local device is not network capable\n",
519 			       DRV_NAME);
520 			rionet_check = 1;
521 			rionet_capable = 0;
522 			goto out;
523 		}
524 
525 		rc = rionet_setup_netdev(rdev->net->hport, ndev);
526 		rionet_check = 1;
527 	}
528 
529 	/*
530 	 * If the remote device has mailbox/doorbell capabilities,
531 	 * add it to the peer list.
532 	 */
533 	if (dev_rionet_capable(rdev)) {
534 		if (!(peer = kmalloc(sizeof(struct rionet_peer), GFP_KERNEL))) {
535 			rc = -ENOMEM;
536 			goto out;
537 		}
538 		peer->rdev = rdev;
539 		list_add_tail(&peer->node, &rionet_peers);
540 	}
541 
542 	rio_set_drvdata(rdev, ndev);
543 
544       out:
545 	return rc;
546 }
547 
548 static struct rio_device_id rionet_id_table[] = {
549 	{RIO_DEVICE(RIO_ANY_ID, RIO_ANY_ID)}
550 };
551 
552 static struct rio_driver rionet_driver = {
553 	.name = "rionet",
554 	.id_table = rionet_id_table,
555 	.probe = rionet_probe,
556 	.remove = rionet_remove,
557 };
558 
559 static int __init rionet_init(void)
560 {
561 	return rio_register_driver(&rionet_driver);
562 }
563 
564 static void __exit rionet_exit(void)
565 {
566 	rio_unregister_driver(&rionet_driver);
567 }
568 
569 late_initcall(rionet_init);
570 module_exit(rionet_exit);
571