xref: /openbmc/linux/drivers/net/rionet.c (revision 643d1f7f)
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 	int rx_slot;
57 	int tx_slot;
58 	int tx_cnt;
59 	int ack_slot;
60 	spinlock_t lock;
61 	spinlock_t tx_lock;
62 	u32 msg_enable;
63 };
64 
65 struct rionet_peer {
66 	struct list_head node;
67 	struct rio_dev *rdev;
68 	struct resource *res;
69 };
70 
71 static int rionet_check = 0;
72 static int rionet_capable = 1;
73 
74 /*
75  * This is a fast lookup table for for translating TX
76  * Ethernet packets into a destination RIO device. It
77  * could be made into a hash table to save memory depending
78  * on system trade-offs.
79  */
80 static struct rio_dev *rionet_active[RIO_MAX_ROUTE_ENTRIES];
81 
82 #define is_rionet_capable(pef, src_ops, dst_ops)		\
83 			((pef & RIO_PEF_INB_MBOX) &&		\
84 			 (pef & RIO_PEF_INB_DOORBELL) &&	\
85 			 (src_ops & RIO_SRC_OPS_DOORBELL) &&	\
86 			 (dst_ops & RIO_DST_OPS_DOORBELL))
87 #define dev_rionet_capable(dev) \
88 	is_rionet_capable(dev->pef, dev->src_ops, dev->dst_ops)
89 
90 #define RIONET_MAC_MATCH(x)	(*(u32 *)x == 0x00010001)
91 #define RIONET_GET_DESTID(x)	(*(u16 *)(x + 4))
92 
93 static int rionet_rx_clean(struct net_device *ndev)
94 {
95 	int i;
96 	int error = 0;
97 	struct rionet_private *rnet = ndev->priv;
98 	void *data;
99 
100 	i = rnet->rx_slot;
101 
102 	do {
103 		if (!rnet->rx_skb[i])
104 			continue;
105 
106 		if (!(data = rio_get_inb_message(rnet->mport, RIONET_MAILBOX)))
107 			break;
108 
109 		rnet->rx_skb[i]->data = data;
110 		skb_put(rnet->rx_skb[i], RIO_MAX_MSG_SIZE);
111 		rnet->rx_skb[i]->protocol =
112 		    eth_type_trans(rnet->rx_skb[i], ndev);
113 		error = netif_rx(rnet->rx_skb[i]);
114 
115 		if (error == NET_RX_DROP) {
116 			ndev->stats.rx_dropped++;
117 		} else if (error == NET_RX_BAD) {
118 			if (netif_msg_rx_err(rnet))
119 				printk(KERN_WARNING "%s: bad rx packet\n",
120 				       DRV_NAME);
121 			ndev->stats.rx_errors++;
122 		} else {
123 			ndev->stats.rx_packets++;
124 			ndev->stats.rx_bytes += RIO_MAX_MSG_SIZE;
125 		}
126 
127 	} while ((i = (i + 1) % RIONET_RX_RING_SIZE) != rnet->rx_slot);
128 
129 	return i;
130 }
131 
132 static void rionet_rx_fill(struct net_device *ndev, int end)
133 {
134 	int i;
135 	struct rionet_private *rnet = ndev->priv;
136 
137 	i = rnet->rx_slot;
138 	do {
139 		rnet->rx_skb[i] = dev_alloc_skb(RIO_MAX_MSG_SIZE);
140 
141 		if (!rnet->rx_skb[i])
142 			break;
143 
144 		rio_add_inb_buffer(rnet->mport, RIONET_MAILBOX,
145 				   rnet->rx_skb[i]->data);
146 	} while ((i = (i + 1) % RIONET_RX_RING_SIZE) != end);
147 
148 	rnet->rx_slot = i;
149 }
150 
151 static int rionet_queue_tx_msg(struct sk_buff *skb, struct net_device *ndev,
152 			       struct rio_dev *rdev)
153 {
154 	struct rionet_private *rnet = ndev->priv;
155 
156 	rio_add_outb_message(rnet->mport, rdev, 0, skb->data, skb->len);
157 	rnet->tx_skb[rnet->tx_slot] = skb;
158 
159 	ndev->stats.tx_packets++;
160 	ndev->stats.tx_bytes += skb->len;
161 
162 	if (++rnet->tx_cnt == RIONET_TX_RING_SIZE)
163 		netif_stop_queue(ndev);
164 
165 	++rnet->tx_slot;
166 	rnet->tx_slot &= (RIONET_TX_RING_SIZE - 1);
167 
168 	if (netif_msg_tx_queued(rnet))
169 		printk(KERN_INFO "%s: queued skb %8.8x len %8.8x\n", DRV_NAME,
170 		       (u32) skb, skb->len);
171 
172 	return 0;
173 }
174 
175 static int rionet_start_xmit(struct sk_buff *skb, struct net_device *ndev)
176 {
177 	int i;
178 	struct rionet_private *rnet = ndev->priv;
179 	struct ethhdr *eth = (struct ethhdr *)skb->data;
180 	u16 destid;
181 	unsigned long flags;
182 
183 	local_irq_save(flags);
184 	if (!spin_trylock(&rnet->tx_lock)) {
185 		local_irq_restore(flags);
186 		return NETDEV_TX_LOCKED;
187 	}
188 
189 	if ((rnet->tx_cnt + 1) > RIONET_TX_RING_SIZE) {
190 		netif_stop_queue(ndev);
191 		spin_unlock_irqrestore(&rnet->tx_lock, flags);
192 		printk(KERN_ERR "%s: BUG! Tx Ring full when queue awake!\n",
193 		       ndev->name);
194 		return NETDEV_TX_BUSY;
195 	}
196 
197 	if (eth->h_dest[0] & 0x01) {
198 		for (i = 0; i < RIO_MAX_ROUTE_ENTRIES; i++)
199 			if (rionet_active[i])
200 				rionet_queue_tx_msg(skb, ndev,
201 						    rionet_active[i]);
202 	} else if (RIONET_MAC_MATCH(eth->h_dest)) {
203 		destid = RIONET_GET_DESTID(eth->h_dest);
204 		if (rionet_active[destid])
205 			rionet_queue_tx_msg(skb, ndev, rionet_active[destid]);
206 	}
207 
208 	spin_unlock_irqrestore(&rnet->tx_lock, flags);
209 
210 	return 0;
211 }
212 
213 static void rionet_dbell_event(struct rio_mport *mport, void *dev_id, u16 sid, u16 tid,
214 			       u16 info)
215 {
216 	struct net_device *ndev = dev_id;
217 	struct rionet_private *rnet = ndev->priv;
218 	struct rionet_peer *peer;
219 
220 	if (netif_msg_intr(rnet))
221 		printk(KERN_INFO "%s: doorbell sid %4.4x tid %4.4x info %4.4x",
222 		       DRV_NAME, sid, tid, info);
223 	if (info == RIONET_DOORBELL_JOIN) {
224 		if (!rionet_active[sid]) {
225 			list_for_each_entry(peer, &rionet_peers, node) {
226 				if (peer->rdev->destid == sid)
227 					rionet_active[sid] = peer->rdev;
228 			}
229 			rio_mport_send_doorbell(mport, sid,
230 						RIONET_DOORBELL_JOIN);
231 		}
232 	} else if (info == RIONET_DOORBELL_LEAVE) {
233 		rionet_active[sid] = NULL;
234 	} else {
235 		if (netif_msg_intr(rnet))
236 			printk(KERN_WARNING "%s: unhandled doorbell\n",
237 			       DRV_NAME);
238 	}
239 }
240 
241 static void rionet_inb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
242 {
243 	int n;
244 	struct net_device *ndev = dev_id;
245 	struct rionet_private *rnet = (struct rionet_private *)ndev->priv;
246 
247 	if (netif_msg_intr(rnet))
248 		printk(KERN_INFO "%s: inbound message event, mbox %d slot %d\n",
249 		       DRV_NAME, mbox, slot);
250 
251 	spin_lock(&rnet->lock);
252 	if ((n = rionet_rx_clean(ndev)) != rnet->rx_slot)
253 		rionet_rx_fill(ndev, n);
254 	spin_unlock(&rnet->lock);
255 }
256 
257 static void rionet_outb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
258 {
259 	struct net_device *ndev = dev_id;
260 	struct rionet_private *rnet = ndev->priv;
261 
262 	spin_lock(&rnet->lock);
263 
264 	if (netif_msg_intr(rnet))
265 		printk(KERN_INFO
266 		       "%s: outbound message event, mbox %d slot %d\n",
267 		       DRV_NAME, mbox, slot);
268 
269 	while (rnet->tx_cnt && (rnet->ack_slot != slot)) {
270 		/* dma unmap single */
271 		dev_kfree_skb_irq(rnet->tx_skb[rnet->ack_slot]);
272 		rnet->tx_skb[rnet->ack_slot] = NULL;
273 		++rnet->ack_slot;
274 		rnet->ack_slot &= (RIONET_TX_RING_SIZE - 1);
275 		rnet->tx_cnt--;
276 	}
277 
278 	if (rnet->tx_cnt < RIONET_TX_RING_SIZE)
279 		netif_wake_queue(ndev);
280 
281 	spin_unlock(&rnet->lock);
282 }
283 
284 static int rionet_open(struct net_device *ndev)
285 {
286 	int i, rc = 0;
287 	struct rionet_peer *peer, *tmp;
288 	u32 pwdcsr;
289 	struct rionet_private *rnet = ndev->priv;
290 
291 	if (netif_msg_ifup(rnet))
292 		printk(KERN_INFO "%s: open\n", DRV_NAME);
293 
294 	if ((rc = rio_request_inb_dbell(rnet->mport,
295 					(void *)ndev,
296 					RIONET_DOORBELL_JOIN,
297 					RIONET_DOORBELL_LEAVE,
298 					rionet_dbell_event)) < 0)
299 		goto out;
300 
301 	if ((rc = rio_request_inb_mbox(rnet->mport,
302 				       (void *)ndev,
303 				       RIONET_MAILBOX,
304 				       RIONET_RX_RING_SIZE,
305 				       rionet_inb_msg_event)) < 0)
306 		goto out;
307 
308 	if ((rc = rio_request_outb_mbox(rnet->mport,
309 					(void *)ndev,
310 					RIONET_MAILBOX,
311 					RIONET_TX_RING_SIZE,
312 					rionet_outb_msg_event)) < 0)
313 		goto out;
314 
315 	/* Initialize inbound message ring */
316 	for (i = 0; i < RIONET_RX_RING_SIZE; i++)
317 		rnet->rx_skb[i] = NULL;
318 	rnet->rx_slot = 0;
319 	rionet_rx_fill(ndev, 0);
320 
321 	rnet->tx_slot = 0;
322 	rnet->tx_cnt = 0;
323 	rnet->ack_slot = 0;
324 
325 	netif_carrier_on(ndev);
326 	netif_start_queue(ndev);
327 
328 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
329 		if (!(peer->res = rio_request_outb_dbell(peer->rdev,
330 							 RIONET_DOORBELL_JOIN,
331 							 RIONET_DOORBELL_LEAVE)))
332 		{
333 			printk(KERN_ERR "%s: error requesting doorbells\n",
334 			       DRV_NAME);
335 			continue;
336 		}
337 
338 		/*
339 		 * If device has initialized inbound doorbells,
340 		 * send a join message
341 		 */
342 		rio_read_config_32(peer->rdev, RIO_WRITE_PORT_CSR, &pwdcsr);
343 		if (pwdcsr & RIO_DOORBELL_AVAIL)
344 			rio_send_doorbell(peer->rdev, RIONET_DOORBELL_JOIN);
345 	}
346 
347       out:
348 	return rc;
349 }
350 
351 static int rionet_close(struct net_device *ndev)
352 {
353 	struct rionet_private *rnet = (struct rionet_private *)ndev->priv;
354 	struct rionet_peer *peer, *tmp;
355 	int i;
356 
357 	if (netif_msg_ifup(rnet))
358 		printk(KERN_INFO "%s: close\n", DRV_NAME);
359 
360 	netif_stop_queue(ndev);
361 	netif_carrier_off(ndev);
362 
363 	for (i = 0; i < RIONET_RX_RING_SIZE; i++)
364 		if (rnet->rx_skb[i])
365 			kfree_skb(rnet->rx_skb[i]);
366 
367 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
368 		if (rionet_active[peer->rdev->destid]) {
369 			rio_send_doorbell(peer->rdev, RIONET_DOORBELL_LEAVE);
370 			rionet_active[peer->rdev->destid] = NULL;
371 		}
372 		rio_release_outb_dbell(peer->rdev, peer->res);
373 	}
374 
375 	rio_release_inb_dbell(rnet->mport, RIONET_DOORBELL_JOIN,
376 			      RIONET_DOORBELL_LEAVE);
377 	rio_release_inb_mbox(rnet->mport, RIONET_MAILBOX);
378 	rio_release_outb_mbox(rnet->mport, RIONET_MAILBOX);
379 
380 	return 0;
381 }
382 
383 static void rionet_remove(struct rio_dev *rdev)
384 {
385 	struct net_device *ndev = NULL;
386 	struct rionet_peer *peer, *tmp;
387 
388 	unregister_netdev(ndev);
389 	kfree(ndev);
390 
391 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
392 		list_del(&peer->node);
393 		kfree(peer);
394 	}
395 }
396 
397 static void rionet_get_drvinfo(struct net_device *ndev,
398 			       struct ethtool_drvinfo *info)
399 {
400 	struct rionet_private *rnet = ndev->priv;
401 
402 	strcpy(info->driver, DRV_NAME);
403 	strcpy(info->version, DRV_VERSION);
404 	strcpy(info->fw_version, "n/a");
405 	strcpy(info->bus_info, rnet->mport->name);
406 }
407 
408 static u32 rionet_get_msglevel(struct net_device *ndev)
409 {
410 	struct rionet_private *rnet = ndev->priv;
411 
412 	return rnet->msg_enable;
413 }
414 
415 static void rionet_set_msglevel(struct net_device *ndev, u32 value)
416 {
417 	struct rionet_private *rnet = ndev->priv;
418 
419 	rnet->msg_enable = value;
420 }
421 
422 static const struct ethtool_ops rionet_ethtool_ops = {
423 	.get_drvinfo = rionet_get_drvinfo,
424 	.get_msglevel = rionet_get_msglevel,
425 	.set_msglevel = rionet_set_msglevel,
426 	.get_link = ethtool_op_get_link,
427 };
428 
429 static int rionet_setup_netdev(struct rio_mport *mport)
430 {
431 	int rc = 0;
432 	struct net_device *ndev = NULL;
433 	struct rionet_private *rnet;
434 	u16 device_id;
435 	DECLARE_MAC_BUF(mac);
436 
437 	/* Allocate our net_device structure */
438 	ndev = alloc_etherdev(sizeof(struct rionet_private));
439 	if (ndev == NULL) {
440 		printk(KERN_INFO "%s: could not allocate ethernet device.\n",
441 		       DRV_NAME);
442 		rc = -ENOMEM;
443 		goto out;
444 	}
445 
446 	/* Set up private area */
447 	rnet = (struct rionet_private *)ndev->priv;
448 	rnet->mport = mport;
449 
450 	/* Set the default MAC address */
451 	device_id = rio_local_get_device_id(mport);
452 	ndev->dev_addr[0] = 0x00;
453 	ndev->dev_addr[1] = 0x01;
454 	ndev->dev_addr[2] = 0x00;
455 	ndev->dev_addr[3] = 0x01;
456 	ndev->dev_addr[4] = device_id >> 8;
457 	ndev->dev_addr[5] = device_id & 0xff;
458 
459 	/* Fill in the driver function table */
460 	ndev->open = &rionet_open;
461 	ndev->hard_start_xmit = &rionet_start_xmit;
462 	ndev->stop = &rionet_close;
463 	ndev->mtu = RIO_MAX_MSG_SIZE - 14;
464 	ndev->features = NETIF_F_LLTX;
465 	SET_ETHTOOL_OPS(ndev, &rionet_ethtool_ops);
466 
467 	spin_lock_init(&rnet->lock);
468 	spin_lock_init(&rnet->tx_lock);
469 
470 	rnet->msg_enable = RIONET_DEFAULT_MSGLEVEL;
471 
472 	rc = register_netdev(ndev);
473 	if (rc != 0)
474 		goto out;
475 
476 	printk("%s: %s %s Version %s, MAC %s\n",
477 	       ndev->name,
478 	       DRV_NAME,
479 	       DRV_DESC,
480 	       DRV_VERSION,
481 	       print_mac(mac, ndev->dev_addr));
482 
483       out:
484 	return rc;
485 }
486 
487 /*
488  * XXX Make multi-net safe
489  */
490 static int rionet_probe(struct rio_dev *rdev, const struct rio_device_id *id)
491 {
492 	int rc = -ENODEV;
493 	u32 lpef, lsrc_ops, ldst_ops;
494 	struct rionet_peer *peer;
495 
496 	/* If local device is not rionet capable, give up quickly */
497 	if (!rionet_capable)
498 		goto out;
499 
500 	/*
501 	 * First time through, make sure local device is rionet
502 	 * capable, setup netdev,  and set flags so this is skipped
503 	 * on later probes
504 	 */
505 	if (!rionet_check) {
506 		rio_local_read_config_32(rdev->net->hport, RIO_PEF_CAR, &lpef);
507 		rio_local_read_config_32(rdev->net->hport, RIO_SRC_OPS_CAR,
508 					 &lsrc_ops);
509 		rio_local_read_config_32(rdev->net->hport, RIO_DST_OPS_CAR,
510 					 &ldst_ops);
511 		if (!is_rionet_capable(lpef, lsrc_ops, ldst_ops)) {
512 			printk(KERN_ERR
513 			       "%s: local device is not network capable\n",
514 			       DRV_NAME);
515 			rionet_check = 1;
516 			rionet_capable = 0;
517 			goto out;
518 		}
519 
520 		rc = rionet_setup_netdev(rdev->net->hport);
521 		rionet_check = 1;
522 	}
523 
524 	/*
525 	 * If the remote device has mailbox/doorbell capabilities,
526 	 * add it to the peer list.
527 	 */
528 	if (dev_rionet_capable(rdev)) {
529 		if (!(peer = kmalloc(sizeof(struct rionet_peer), GFP_KERNEL))) {
530 			rc = -ENOMEM;
531 			goto out;
532 		}
533 		peer->rdev = rdev;
534 		list_add_tail(&peer->node, &rionet_peers);
535 	}
536 
537       out:
538 	return rc;
539 }
540 
541 static struct rio_device_id rionet_id_table[] = {
542 	{RIO_DEVICE(RIO_ANY_ID, RIO_ANY_ID)}
543 };
544 
545 static struct rio_driver rionet_driver = {
546 	.name = "rionet",
547 	.id_table = rionet_id_table,
548 	.probe = rionet_probe,
549 	.remove = rionet_remove,
550 };
551 
552 static int __init rionet_init(void)
553 {
554 	return rio_register_driver(&rionet_driver);
555 }
556 
557 static void __exit rionet_exit(void)
558 {
559 	rio_unregister_driver(&rionet_driver);
560 }
561 
562 module_init(rionet_init);
563 module_exit(rionet_exit);
564