xref: /openbmc/linux/drivers/net/rionet.c (revision 82ced6fd)
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;
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 = netdev_priv(ndev);
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 = netdev_priv(ndev);
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 = netdev_priv(ndev);
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 = netdev_priv(ndev);
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(rnet->mport->sys_size);
199 				i++)
200 			if (rionet_active[i])
201 				rionet_queue_tx_msg(skb, ndev,
202 						    rionet_active[i]);
203 	} else if (RIONET_MAC_MATCH(eth->h_dest)) {
204 		destid = RIONET_GET_DESTID(eth->h_dest);
205 		if (rionet_active[destid])
206 			rionet_queue_tx_msg(skb, ndev, rionet_active[destid]);
207 	}
208 
209 	spin_unlock_irqrestore(&rnet->tx_lock, flags);
210 
211 	return 0;
212 }
213 
214 static void rionet_dbell_event(struct rio_mport *mport, void *dev_id, u16 sid, u16 tid,
215 			       u16 info)
216 {
217 	struct net_device *ndev = dev_id;
218 	struct rionet_private *rnet = netdev_priv(ndev);
219 	struct rionet_peer *peer;
220 
221 	if (netif_msg_intr(rnet))
222 		printk(KERN_INFO "%s: doorbell sid %4.4x tid %4.4x info %4.4x",
223 		       DRV_NAME, sid, tid, info);
224 	if (info == RIONET_DOORBELL_JOIN) {
225 		if (!rionet_active[sid]) {
226 			list_for_each_entry(peer, &rionet_peers, node) {
227 				if (peer->rdev->destid == sid)
228 					rionet_active[sid] = peer->rdev;
229 			}
230 			rio_mport_send_doorbell(mport, sid,
231 						RIONET_DOORBELL_JOIN);
232 		}
233 	} else if (info == RIONET_DOORBELL_LEAVE) {
234 		rionet_active[sid] = NULL;
235 	} else {
236 		if (netif_msg_intr(rnet))
237 			printk(KERN_WARNING "%s: unhandled doorbell\n",
238 			       DRV_NAME);
239 	}
240 }
241 
242 static void rionet_inb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
243 {
244 	int n;
245 	struct net_device *ndev = dev_id;
246 	struct rionet_private *rnet = netdev_priv(ndev);
247 
248 	if (netif_msg_intr(rnet))
249 		printk(KERN_INFO "%s: inbound message event, mbox %d slot %d\n",
250 		       DRV_NAME, mbox, slot);
251 
252 	spin_lock(&rnet->lock);
253 	if ((n = rionet_rx_clean(ndev)) != rnet->rx_slot)
254 		rionet_rx_fill(ndev, n);
255 	spin_unlock(&rnet->lock);
256 }
257 
258 static void rionet_outb_msg_event(struct rio_mport *mport, void *dev_id, int mbox, int slot)
259 {
260 	struct net_device *ndev = dev_id;
261 	struct rionet_private *rnet = netdev_priv(ndev);
262 
263 	spin_lock(&rnet->lock);
264 
265 	if (netif_msg_intr(rnet))
266 		printk(KERN_INFO
267 		       "%s: outbound message event, mbox %d slot %d\n",
268 		       DRV_NAME, mbox, slot);
269 
270 	while (rnet->tx_cnt && (rnet->ack_slot != slot)) {
271 		/* dma unmap single */
272 		dev_kfree_skb_irq(rnet->tx_skb[rnet->ack_slot]);
273 		rnet->tx_skb[rnet->ack_slot] = NULL;
274 		++rnet->ack_slot;
275 		rnet->ack_slot &= (RIONET_TX_RING_SIZE - 1);
276 		rnet->tx_cnt--;
277 	}
278 
279 	if (rnet->tx_cnt < RIONET_TX_RING_SIZE)
280 		netif_wake_queue(ndev);
281 
282 	spin_unlock(&rnet->lock);
283 }
284 
285 static int rionet_open(struct net_device *ndev)
286 {
287 	int i, rc = 0;
288 	struct rionet_peer *peer, *tmp;
289 	u32 pwdcsr;
290 	struct rionet_private *rnet = netdev_priv(ndev);
291 
292 	if (netif_msg_ifup(rnet))
293 		printk(KERN_INFO "%s: open\n", DRV_NAME);
294 
295 	if ((rc = rio_request_inb_dbell(rnet->mport,
296 					(void *)ndev,
297 					RIONET_DOORBELL_JOIN,
298 					RIONET_DOORBELL_LEAVE,
299 					rionet_dbell_event)) < 0)
300 		goto out;
301 
302 	if ((rc = rio_request_inb_mbox(rnet->mport,
303 				       (void *)ndev,
304 				       RIONET_MAILBOX,
305 				       RIONET_RX_RING_SIZE,
306 				       rionet_inb_msg_event)) < 0)
307 		goto out;
308 
309 	if ((rc = rio_request_outb_mbox(rnet->mport,
310 					(void *)ndev,
311 					RIONET_MAILBOX,
312 					RIONET_TX_RING_SIZE,
313 					rionet_outb_msg_event)) < 0)
314 		goto out;
315 
316 	/* Initialize inbound message ring */
317 	for (i = 0; i < RIONET_RX_RING_SIZE; i++)
318 		rnet->rx_skb[i] = NULL;
319 	rnet->rx_slot = 0;
320 	rionet_rx_fill(ndev, 0);
321 
322 	rnet->tx_slot = 0;
323 	rnet->tx_cnt = 0;
324 	rnet->ack_slot = 0;
325 
326 	netif_carrier_on(ndev);
327 	netif_start_queue(ndev);
328 
329 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
330 		if (!(peer->res = rio_request_outb_dbell(peer->rdev,
331 							 RIONET_DOORBELL_JOIN,
332 							 RIONET_DOORBELL_LEAVE)))
333 		{
334 			printk(KERN_ERR "%s: error requesting doorbells\n",
335 			       DRV_NAME);
336 			continue;
337 		}
338 
339 		/*
340 		 * If device has initialized inbound doorbells,
341 		 * send a join message
342 		 */
343 		rio_read_config_32(peer->rdev, RIO_WRITE_PORT_CSR, &pwdcsr);
344 		if (pwdcsr & RIO_DOORBELL_AVAIL)
345 			rio_send_doorbell(peer->rdev, RIONET_DOORBELL_JOIN);
346 	}
347 
348       out:
349 	return rc;
350 }
351 
352 static int rionet_close(struct net_device *ndev)
353 {
354 	struct rionet_private *rnet = netdev_priv(ndev);
355 	struct rionet_peer *peer, *tmp;
356 	int i;
357 
358 	if (netif_msg_ifup(rnet))
359 		printk(KERN_INFO "%s: close\n", DRV_NAME);
360 
361 	netif_stop_queue(ndev);
362 	netif_carrier_off(ndev);
363 
364 	for (i = 0; i < RIONET_RX_RING_SIZE; 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 	free_pages((unsigned long)rionet_active, rdev->net->hport->sys_size ?
389 					__ilog2(sizeof(void *)) + 4 : 0);
390 	unregister_netdev(ndev);
391 	kfree(ndev);
392 
393 	list_for_each_entry_safe(peer, tmp, &rionet_peers, node) {
394 		list_del(&peer->node);
395 		kfree(peer);
396 	}
397 }
398 
399 static void rionet_get_drvinfo(struct net_device *ndev,
400 			       struct ethtool_drvinfo *info)
401 {
402 	struct rionet_private *rnet = netdev_priv(ndev);
403 
404 	strcpy(info->driver, DRV_NAME);
405 	strcpy(info->version, DRV_VERSION);
406 	strcpy(info->fw_version, "n/a");
407 	strcpy(info->bus_info, rnet->mport->name);
408 }
409 
410 static u32 rionet_get_msglevel(struct net_device *ndev)
411 {
412 	struct rionet_private *rnet = netdev_priv(ndev);
413 
414 	return rnet->msg_enable;
415 }
416 
417 static void rionet_set_msglevel(struct net_device *ndev, u32 value)
418 {
419 	struct rionet_private *rnet = netdev_priv(ndev);
420 
421 	rnet->msg_enable = value;
422 }
423 
424 static const struct ethtool_ops rionet_ethtool_ops = {
425 	.get_drvinfo = rionet_get_drvinfo,
426 	.get_msglevel = rionet_get_msglevel,
427 	.set_msglevel = rionet_set_msglevel,
428 	.get_link = ethtool_op_get_link,
429 };
430 
431 static int rionet_setup_netdev(struct rio_mport *mport)
432 {
433 	int rc = 0;
434 	struct net_device *ndev = NULL;
435 	struct rionet_private *rnet;
436 	u16 device_id;
437 
438 	/* Allocate our net_device structure */
439 	ndev = alloc_etherdev(sizeof(struct rionet_private));
440 	if (ndev == NULL) {
441 		printk(KERN_INFO "%s: could not allocate ethernet device.\n",
442 		       DRV_NAME);
443 		rc = -ENOMEM;
444 		goto out;
445 	}
446 
447 	rionet_active = (struct rio_dev **)__get_free_pages(GFP_KERNEL,
448 			mport->sys_size ? __ilog2(sizeof(void *)) + 4 : 0);
449 	if (!rionet_active) {
450 		rc = -ENOMEM;
451 		goto out;
452 	}
453 	memset((void *)rionet_active, 0, sizeof(void *) *
454 				RIO_MAX_ROUTE_ENTRIES(mport->sys_size));
455 
456 	/* Set up private area */
457 	rnet = netdev_priv(ndev);
458 	rnet->mport = mport;
459 
460 	/* Set the default MAC address */
461 	device_id = rio_local_get_device_id(mport);
462 	ndev->dev_addr[0] = 0x00;
463 	ndev->dev_addr[1] = 0x01;
464 	ndev->dev_addr[2] = 0x00;
465 	ndev->dev_addr[3] = 0x01;
466 	ndev->dev_addr[4] = device_id >> 8;
467 	ndev->dev_addr[5] = device_id & 0xff;
468 
469 	/* Fill in the driver function table */
470 	ndev->open = &rionet_open;
471 	ndev->hard_start_xmit = &rionet_start_xmit;
472 	ndev->stop = &rionet_close;
473 	ndev->mtu = RIO_MAX_MSG_SIZE - 14;
474 	ndev->features = NETIF_F_LLTX;
475 	SET_ETHTOOL_OPS(ndev, &rionet_ethtool_ops);
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 %pM\n",
487 	       ndev->name,
488 	       DRV_NAME,
489 	       DRV_DESC,
490 	       DRV_VERSION,
491 	       ndev->dev_addr);
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