xref: /openbmc/linux/drivers/net/rionet.c (revision e868d61272caa648214046a096e5a6bfc068dc8c)
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]->protocol =
119 		    eth_type_trans(rnet->rx_skb[i], ndev);
120 		error = netif_rx(rnet->rx_skb[i]);
121 
122 		if (error == NET_RX_DROP) {
123 			rnet->stats.rx_dropped++;
124 		} else if (error == NET_RX_BAD) {
125 			if (netif_msg_rx_err(rnet))
126 				printk(KERN_WARNING "%s: bad rx packet\n",
127 				       DRV_NAME);
128 			rnet->stats.rx_errors++;
129 		} else {
130 			rnet->stats.rx_packets++;
131 			rnet->stats.rx_bytes += RIO_MAX_MSG_SIZE;
132 		}
133 
134 	} while ((i = (i + 1) % RIONET_RX_RING_SIZE) != rnet->rx_slot);
135 
136 	return i;
137 }
138 
139 static void rionet_rx_fill(struct net_device *ndev, int end)
140 {
141 	int i;
142 	struct rionet_private *rnet = ndev->priv;
143 
144 	i = rnet->rx_slot;
145 	do {
146 		rnet->rx_skb[i] = dev_alloc_skb(RIO_MAX_MSG_SIZE);
147 
148 		if (!rnet->rx_skb[i])
149 			break;
150 
151 		rio_add_inb_buffer(rnet->mport, RIONET_MAILBOX,
152 				   rnet->rx_skb[i]->data);
153 	} while ((i = (i + 1) % RIONET_RX_RING_SIZE) != end);
154 
155 	rnet->rx_slot = i;
156 }
157 
158 static int rionet_queue_tx_msg(struct sk_buff *skb, struct net_device *ndev,
159 			       struct rio_dev *rdev)
160 {
161 	struct rionet_private *rnet = ndev->priv;
162 
163 	rio_add_outb_message(rnet->mport, rdev, 0, skb->data, skb->len);
164 	rnet->tx_skb[rnet->tx_slot] = skb;
165 
166 	rnet->stats.tx_packets++;
167 	rnet->stats.tx_bytes += skb->len;
168 
169 	if (++rnet->tx_cnt == RIONET_TX_RING_SIZE)
170 		netif_stop_queue(ndev);
171 
172 	++rnet->tx_slot;
173 	rnet->tx_slot &= (RIONET_TX_RING_SIZE - 1);
174 
175 	if (netif_msg_tx_queued(rnet))
176 		printk(KERN_INFO "%s: queued skb %8.8x len %8.8x\n", DRV_NAME,
177 		       (u32) skb, skb->len);
178 
179 	return 0;
180 }
181 
182 static int rionet_start_xmit(struct sk_buff *skb, struct net_device *ndev)
183 {
184 	int i;
185 	struct rionet_private *rnet = ndev->priv;
186 	struct ethhdr *eth = (struct ethhdr *)skb->data;
187 	u16 destid;
188 	unsigned long flags;
189 
190 	local_irq_save(flags);
191 	if (!spin_trylock(&rnet->tx_lock)) {
192 		local_irq_restore(flags);
193 		return NETDEV_TX_LOCKED;
194 	}
195 
196 	if ((rnet->tx_cnt + 1) > RIONET_TX_RING_SIZE) {
197 		netif_stop_queue(ndev);
198 		spin_unlock_irqrestore(&rnet->tx_lock, flags);
199 		printk(KERN_ERR "%s: BUG! Tx Ring full when queue awake!\n",
200 		       ndev->name);
201 		return NETDEV_TX_BUSY;
202 	}
203 
204 	if (eth->h_dest[0] & 0x01) {
205 		for (i = 0; i < RIO_MAX_ROUTE_ENTRIES; i++)
206 			if (rionet_active[i])
207 				rionet_queue_tx_msg(skb, ndev,
208 						    rionet_active[i]);
209 	} else if (RIONET_MAC_MATCH(eth->h_dest)) {
210 		destid = RIONET_GET_DESTID(eth->h_dest);
211 		if (rionet_active[destid])
212 			rionet_queue_tx_msg(skb, ndev, rionet_active[destid]);
213 	}
214 
215 	spin_unlock_irqrestore(&rnet->tx_lock, flags);
216 
217 	return 0;
218 }
219 
220 static void rionet_dbell_event(struct rio_mport *mport, void *dev_id, u16 sid, u16 tid,
221 			       u16 info)
222 {
223 	struct net_device *ndev = dev_id;
224 	struct rionet_private *rnet = ndev->priv;
225 	struct rionet_peer *peer;
226 
227 	if (netif_msg_intr(rnet))
228 		printk(KERN_INFO "%s: doorbell sid %4.4x tid %4.4x info %4.4x",
229 		       DRV_NAME, sid, tid, info);
230 	if (info == RIONET_DOORBELL_JOIN) {
231 		if (!rionet_active[sid]) {
232 			list_for_each_entry(peer, &rionet_peers, node) {
233 				if (peer->rdev->destid == sid)
234 					rionet_active[sid] = peer->rdev;
235 			}
236 			rio_mport_send_doorbell(mport, sid,
237 						RIONET_DOORBELL_JOIN);
238 		}
239 	} else if (info == RIONET_DOORBELL_LEAVE) {
240 		rionet_active[sid] = NULL;
241 	} else {
242 		if (netif_msg_intr(rnet))
243 			printk(KERN_WARNING "%s: unhandled doorbell\n",
244 			       DRV_NAME);
245 	}
246 }
247 
248 static void rionet_inb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
249 {
250 	int n;
251 	struct net_device *ndev = dev_id;
252 	struct rionet_private *rnet = (struct rionet_private *)ndev->priv;
253 
254 	if (netif_msg_intr(rnet))
255 		printk(KERN_INFO "%s: inbound message event, mbox %d slot %d\n",
256 		       DRV_NAME, mbox, slot);
257 
258 	spin_lock(&rnet->lock);
259 	if ((n = rionet_rx_clean(ndev)) != rnet->rx_slot)
260 		rionet_rx_fill(ndev, n);
261 	spin_unlock(&rnet->lock);
262 }
263 
264 static void rionet_outb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
265 {
266 	struct net_device *ndev = dev_id;
267 	struct rionet_private *rnet = ndev->priv;
268 
269 	spin_lock(&rnet->lock);
270 
271 	if (netif_msg_intr(rnet))
272 		printk(KERN_INFO
273 		       "%s: outbound message event, mbox %d slot %d\n",
274 		       DRV_NAME, mbox, slot);
275 
276 	while (rnet->tx_cnt && (rnet->ack_slot != slot)) {
277 		/* dma unmap single */
278 		dev_kfree_skb_irq(rnet->tx_skb[rnet->ack_slot]);
279 		rnet->tx_skb[rnet->ack_slot] = NULL;
280 		++rnet->ack_slot;
281 		rnet->ack_slot &= (RIONET_TX_RING_SIZE - 1);
282 		rnet->tx_cnt--;
283 	}
284 
285 	if (rnet->tx_cnt < RIONET_TX_RING_SIZE)
286 		netif_wake_queue(ndev);
287 
288 	spin_unlock(&rnet->lock);
289 }
290 
291 static int rionet_open(struct net_device *ndev)
292 {
293 	int i, rc = 0;
294 	struct rionet_peer *peer, *tmp;
295 	u32 pwdcsr;
296 	struct rionet_private *rnet = ndev->priv;
297 
298 	if (netif_msg_ifup(rnet))
299 		printk(KERN_INFO "%s: open\n", DRV_NAME);
300 
301 	if ((rc = rio_request_inb_dbell(rnet->mport,
302 					(void *)ndev,
303 					RIONET_DOORBELL_JOIN,
304 					RIONET_DOORBELL_LEAVE,
305 					rionet_dbell_event)) < 0)
306 		goto out;
307 
308 	if ((rc = rio_request_inb_mbox(rnet->mport,
309 				       (void *)ndev,
310 				       RIONET_MAILBOX,
311 				       RIONET_RX_RING_SIZE,
312 				       rionet_inb_msg_event)) < 0)
313 		goto out;
314 
315 	if ((rc = rio_request_outb_mbox(rnet->mport,
316 					(void *)ndev,
317 					RIONET_MAILBOX,
318 					RIONET_TX_RING_SIZE,
319 					rionet_outb_msg_event)) < 0)
320 		goto out;
321 
322 	/* Initialize inbound message ring */
323 	for (i = 0; i < RIONET_RX_RING_SIZE; i++)
324 		rnet->rx_skb[i] = NULL;
325 	rnet->rx_slot = 0;
326 	rionet_rx_fill(ndev, 0);
327 
328 	rnet->tx_slot = 0;
329 	rnet->tx_cnt = 0;
330 	rnet->ack_slot = 0;
331 
332 	netif_carrier_on(ndev);
333 	netif_start_queue(ndev);
334 
335 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
336 		if (!(peer->res = rio_request_outb_dbell(peer->rdev,
337 							 RIONET_DOORBELL_JOIN,
338 							 RIONET_DOORBELL_LEAVE)))
339 		{
340 			printk(KERN_ERR "%s: error requesting doorbells\n",
341 			       DRV_NAME);
342 			continue;
343 		}
344 
345 		/*
346 		 * If device has initialized inbound doorbells,
347 		 * send a join message
348 		 */
349 		rio_read_config_32(peer->rdev, RIO_WRITE_PORT_CSR, &pwdcsr);
350 		if (pwdcsr & RIO_DOORBELL_AVAIL)
351 			rio_send_doorbell(peer->rdev, RIONET_DOORBELL_JOIN);
352 	}
353 
354       out:
355 	return rc;
356 }
357 
358 static int rionet_close(struct net_device *ndev)
359 {
360 	struct rionet_private *rnet = (struct rionet_private *)ndev->priv;
361 	struct rionet_peer *peer, *tmp;
362 	int i;
363 
364 	if (netif_msg_ifup(rnet))
365 		printk(KERN_INFO "%s: close\n", DRV_NAME);
366 
367 	netif_stop_queue(ndev);
368 	netif_carrier_off(ndev);
369 
370 	for (i = 0; i < RIONET_RX_RING_SIZE; i++)
371 		if (rnet->rx_skb[i])
372 			kfree_skb(rnet->rx_skb[i]);
373 
374 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
375 		if (rionet_active[peer->rdev->destid]) {
376 			rio_send_doorbell(peer->rdev, RIONET_DOORBELL_LEAVE);
377 			rionet_active[peer->rdev->destid] = NULL;
378 		}
379 		rio_release_outb_dbell(peer->rdev, peer->res);
380 	}
381 
382 	rio_release_inb_dbell(rnet->mport, RIONET_DOORBELL_JOIN,
383 			      RIONET_DOORBELL_LEAVE);
384 	rio_release_inb_mbox(rnet->mport, RIONET_MAILBOX);
385 	rio_release_outb_mbox(rnet->mport, RIONET_MAILBOX);
386 
387 	return 0;
388 }
389 
390 static void rionet_remove(struct rio_dev *rdev)
391 {
392 	struct net_device *ndev = NULL;
393 	struct rionet_peer *peer, *tmp;
394 
395 	unregister_netdev(ndev);
396 	kfree(ndev);
397 
398 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
399 		list_del(&peer->node);
400 		kfree(peer);
401 	}
402 }
403 
404 static void rionet_get_drvinfo(struct net_device *ndev,
405 			       struct ethtool_drvinfo *info)
406 {
407 	struct rionet_private *rnet = ndev->priv;
408 
409 	strcpy(info->driver, DRV_NAME);
410 	strcpy(info->version, DRV_VERSION);
411 	strcpy(info->fw_version, "n/a");
412 	strcpy(info->bus_info, rnet->mport->name);
413 }
414 
415 static u32 rionet_get_msglevel(struct net_device *ndev)
416 {
417 	struct rionet_private *rnet = ndev->priv;
418 
419 	return rnet->msg_enable;
420 }
421 
422 static void rionet_set_msglevel(struct net_device *ndev, u32 value)
423 {
424 	struct rionet_private *rnet = ndev->priv;
425 
426 	rnet->msg_enable = value;
427 }
428 
429 static const struct ethtool_ops rionet_ethtool_ops = {
430 	.get_drvinfo = rionet_get_drvinfo,
431 	.get_msglevel = rionet_get_msglevel,
432 	.set_msglevel = rionet_set_msglevel,
433 	.get_link = ethtool_op_get_link,
434 };
435 
436 static int rionet_setup_netdev(struct rio_mport *mport)
437 {
438 	int rc = 0;
439 	struct net_device *ndev = NULL;
440 	struct rionet_private *rnet;
441 	u16 device_id;
442 
443 	/* Allocate our net_device structure */
444 	ndev = alloc_etherdev(sizeof(struct rionet_private));
445 	if (ndev == NULL) {
446 		printk(KERN_INFO "%s: could not allocate ethernet device.\n",
447 		       DRV_NAME);
448 		rc = -ENOMEM;
449 		goto out;
450 	}
451 
452 	/* Set up private area */
453 	rnet = (struct rionet_private *)ndev->priv;
454 	rnet->mport = mport;
455 
456 	/* Set the default MAC address */
457 	device_id = rio_local_get_device_id(mport);
458 	ndev->dev_addr[0] = 0x00;
459 	ndev->dev_addr[1] = 0x01;
460 	ndev->dev_addr[2] = 0x00;
461 	ndev->dev_addr[3] = 0x01;
462 	ndev->dev_addr[4] = device_id >> 8;
463 	ndev->dev_addr[5] = device_id & 0xff;
464 
465 	/* Fill in the driver function table */
466 	ndev->open = &rionet_open;
467 	ndev->hard_start_xmit = &rionet_start_xmit;
468 	ndev->stop = &rionet_close;
469 	ndev->get_stats = &rionet_stats;
470 	ndev->mtu = RIO_MAX_MSG_SIZE - 14;
471 	ndev->features = NETIF_F_LLTX;
472 	SET_ETHTOOL_OPS(ndev, &rionet_ethtool_ops);
473 
474 	SET_MODULE_OWNER(ndev);
475 
476 	spin_lock_init(&rnet->lock);
477 	spin_lock_init(&rnet->tx_lock);
478 
479 	rnet->msg_enable = RIONET_DEFAULT_MSGLEVEL;
480 
481 	rc = register_netdev(ndev);
482 	if (rc != 0)
483 		goto out;
484 
485 	printk("%s: %s %s Version %s, MAC %02x:%02x:%02x:%02x:%02x:%02x\n",
486 	       ndev->name,
487 	       DRV_NAME,
488 	       DRV_DESC,
489 	       DRV_VERSION,
490 	       ndev->dev_addr[0], ndev->dev_addr[1], ndev->dev_addr[2],
491 	       ndev->dev_addr[3], ndev->dev_addr[4], ndev->dev_addr[5]);
492 
493       out:
494 	return rc;
495 }
496 
497 /*
498  * XXX Make multi-net safe
499  */
500 static int rionet_probe(struct rio_dev *rdev, const struct rio_device_id *id)
501 {
502 	int rc = -ENODEV;
503 	u32 lpef, lsrc_ops, ldst_ops;
504 	struct rionet_peer *peer;
505 
506 	/* If local device is not rionet capable, give up quickly */
507 	if (!rionet_capable)
508 		goto out;
509 
510 	/*
511 	 * First time through, make sure local device is rionet
512 	 * capable, setup netdev,  and set flags so this is skipped
513 	 * on later probes
514 	 */
515 	if (!rionet_check) {
516 		rio_local_read_config_32(rdev->net->hport, RIO_PEF_CAR, &lpef);
517 		rio_local_read_config_32(rdev->net->hport, RIO_SRC_OPS_CAR,
518 					 &lsrc_ops);
519 		rio_local_read_config_32(rdev->net->hport, RIO_DST_OPS_CAR,
520 					 &ldst_ops);
521 		if (!is_rionet_capable(lpef, lsrc_ops, ldst_ops)) {
522 			printk(KERN_ERR
523 			       "%s: local device is not network capable\n",
524 			       DRV_NAME);
525 			rionet_check = 1;
526 			rionet_capable = 0;
527 			goto out;
528 		}
529 
530 		rc = rionet_setup_netdev(rdev->net->hport);
531 		rionet_check = 1;
532 	}
533 
534 	/*
535 	 * If the remote device has mailbox/doorbell capabilities,
536 	 * add it to the peer list.
537 	 */
538 	if (dev_rionet_capable(rdev)) {
539 		if (!(peer = kmalloc(sizeof(struct rionet_peer), GFP_KERNEL))) {
540 			rc = -ENOMEM;
541 			goto out;
542 		}
543 		peer->rdev = rdev;
544 		list_add_tail(&peer->node, &rionet_peers);
545 	}
546 
547       out:
548 	return rc;
549 }
550 
551 static struct rio_device_id rionet_id_table[] = {
552 	{RIO_DEVICE(RIO_ANY_ID, RIO_ANY_ID)}
553 };
554 
555 static struct rio_driver rionet_driver = {
556 	.name = "rionet",
557 	.id_table = rionet_id_table,
558 	.probe = rionet_probe,
559 	.remove = rionet_remove,
560 };
561 
562 static int __init rionet_init(void)
563 {
564 	return rio_register_driver(&rionet_driver);
565 }
566 
567 static void __exit rionet_exit(void)
568 {
569 	rio_unregister_driver(&rionet_driver);
570 }
571 
572 module_init(rionet_init);
573 module_exit(rionet_exit);
574