1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * net.c - Networking component for Mostcore |
4 | * |
5 | * Copyright (C) 2015, Microchip Technology Germany II GmbH & Co. KG |
6 | */ |
7 | |
8 | #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt |
9 | |
10 | #include <linux/module.h> |
11 | #include <linux/netdevice.h> |
12 | #include <linux/etherdevice.h> |
13 | #include <linux/slab.h> |
14 | #include <linux/init.h> |
15 | #include <linux/list.h> |
16 | #include <linux/wait.h> |
17 | #include <linux/kobject.h> |
18 | #include <linux/most.h> |
19 | |
20 | #define MEP_HDR_LEN 8 |
21 | #define MDP_HDR_LEN 16 |
22 | #define MAMAC_DATA_LEN (1024 - MDP_HDR_LEN) |
23 | |
24 | #define PMHL 5 |
25 | |
26 | #define PMS_TELID_UNSEGM_MAMAC 0x0A |
27 | #define PMS_FIFONO_MDP 0x01 |
28 | #define PMS_FIFONO_MEP 0x04 |
29 | #define PMS_MSGTYPE_DATA 0x04 |
30 | #define PMS_DEF_PRIO 0 |
31 | #define MEP_DEF_RETRY 15 |
32 | |
33 | #define PMS_FIFONO_MASK 0x07 |
34 | #define PMS_FIFONO_SHIFT 3 |
35 | #define PMS_RETRY_SHIFT 4 |
36 | #define PMS_TELID_MASK 0x0F |
37 | #define PMS_TELID_SHIFT 4 |
38 | |
39 | #define HB(value) ((u8)((u16)(value) >> 8)) |
40 | #define LB(value) ((u8)(value)) |
41 | |
42 | #define (bitset_name, value) \ |
43 | (((value) >> bitset_name##_SHIFT) & bitset_name##_MASK) |
44 | |
45 | #define PMS_IS_MEP(buf, len) \ |
46 | ((len) > MEP_HDR_LEN && \ |
47 | EXTRACT_BIT_SET(PMS_FIFONO, (buf)[3]) == PMS_FIFONO_MEP) |
48 | |
49 | static inline bool pms_is_mamac(char *buf, u32 len) |
50 | { |
51 | return (len > MDP_HDR_LEN && |
52 | EXTRACT_BIT_SET(PMS_FIFONO, buf[3]) == PMS_FIFONO_MDP && |
53 | EXTRACT_BIT_SET(PMS_TELID, buf[14]) == PMS_TELID_UNSEGM_MAMAC); |
54 | } |
55 | |
56 | struct net_dev_channel { |
57 | bool linked; |
58 | int ch_id; |
59 | }; |
60 | |
61 | struct net_dev_context { |
62 | struct most_interface *iface; |
63 | bool is_mamac; |
64 | struct net_device *dev; |
65 | struct net_dev_channel rx; |
66 | struct net_dev_channel tx; |
67 | struct list_head list; |
68 | }; |
69 | |
70 | static LIST_HEAD(net_devices); |
71 | static DEFINE_MUTEX(probe_disc_mt); /* ch->linked = true, most_nd_open */ |
72 | static DEFINE_SPINLOCK(list_lock); /* list_head, ch->linked = false, dev_hold */ |
73 | static struct most_component comp; |
74 | |
75 | static int skb_to_mamac(const struct sk_buff *skb, struct mbo *mbo) |
76 | { |
77 | u8 *buff = mbo->virt_address; |
78 | static const u8 broadcast[] = { 0x03, 0xFF }; |
79 | const u8 *dest_addr = skb->data + 4; |
80 | const u8 *eth_type = skb->data + 12; |
81 | unsigned int payload_len = skb->len - ETH_HLEN; |
82 | unsigned int mdp_len = payload_len + MDP_HDR_LEN; |
83 | |
84 | if (mdp_len < skb->len) { |
85 | pr_err("drop: too large packet! (%u)\n" , skb->len); |
86 | return -EINVAL; |
87 | } |
88 | |
89 | if (mbo->buffer_length < mdp_len) { |
90 | pr_err("drop: too small buffer! (%d for %d)\n" , |
91 | mbo->buffer_length, mdp_len); |
92 | return -EINVAL; |
93 | } |
94 | |
95 | if (skb->len < ETH_HLEN) { |
96 | pr_err("drop: too small packet! (%d)\n" , skb->len); |
97 | return -EINVAL; |
98 | } |
99 | |
100 | if (dest_addr[0] == 0xFF && dest_addr[1] == 0xFF) |
101 | dest_addr = broadcast; |
102 | |
103 | *buff++ = HB(mdp_len - 2); |
104 | *buff++ = LB(mdp_len - 2); |
105 | |
106 | *buff++ = PMHL; |
107 | *buff++ = (PMS_FIFONO_MDP << PMS_FIFONO_SHIFT) | PMS_MSGTYPE_DATA; |
108 | *buff++ = PMS_DEF_PRIO; |
109 | *buff++ = dest_addr[0]; |
110 | *buff++ = dest_addr[1]; |
111 | *buff++ = 0x00; |
112 | |
113 | *buff++ = HB(payload_len + 6); |
114 | *buff++ = LB(payload_len + 6); |
115 | |
116 | /* end of FPH here */ |
117 | |
118 | *buff++ = eth_type[0]; |
119 | *buff++ = eth_type[1]; |
120 | *buff++ = 0; |
121 | *buff++ = 0; |
122 | |
123 | *buff++ = PMS_TELID_UNSEGM_MAMAC << 4 | HB(payload_len); |
124 | *buff++ = LB(payload_len); |
125 | |
126 | memcpy(buff, skb->data + ETH_HLEN, payload_len); |
127 | mbo->buffer_length = mdp_len; |
128 | return 0; |
129 | } |
130 | |
131 | static int skb_to_mep(const struct sk_buff *skb, struct mbo *mbo) |
132 | { |
133 | u8 *buff = mbo->virt_address; |
134 | unsigned int mep_len = skb->len + MEP_HDR_LEN; |
135 | |
136 | if (mep_len < skb->len) { |
137 | pr_err("drop: too large packet! (%u)\n" , skb->len); |
138 | return -EINVAL; |
139 | } |
140 | |
141 | if (mbo->buffer_length < mep_len) { |
142 | pr_err("drop: too small buffer! (%d for %d)\n" , |
143 | mbo->buffer_length, mep_len); |
144 | return -EINVAL; |
145 | } |
146 | |
147 | *buff++ = HB(mep_len - 2); |
148 | *buff++ = LB(mep_len - 2); |
149 | |
150 | *buff++ = PMHL; |
151 | *buff++ = (PMS_FIFONO_MEP << PMS_FIFONO_SHIFT) | PMS_MSGTYPE_DATA; |
152 | *buff++ = (MEP_DEF_RETRY << PMS_RETRY_SHIFT) | PMS_DEF_PRIO; |
153 | *buff++ = 0; |
154 | *buff++ = 0; |
155 | *buff++ = 0; |
156 | |
157 | memcpy(buff, skb->data, skb->len); |
158 | mbo->buffer_length = mep_len; |
159 | return 0; |
160 | } |
161 | |
162 | static int most_nd_set_mac_address(struct net_device *dev, void *p) |
163 | { |
164 | struct net_dev_context *nd = netdev_priv(dev); |
165 | int err = eth_mac_addr(dev, p); |
166 | |
167 | if (err) |
168 | return err; |
169 | |
170 | nd->is_mamac = |
171 | (dev->dev_addr[0] == 0 && dev->dev_addr[1] == 0 && |
172 | dev->dev_addr[2] == 0 && dev->dev_addr[3] == 0); |
173 | |
174 | /* |
175 | * Set default MTU for the given packet type. |
176 | * It is still possible to change MTU using ip tools afterwards. |
177 | */ |
178 | dev->mtu = nd->is_mamac ? MAMAC_DATA_LEN : ETH_DATA_LEN; |
179 | |
180 | return 0; |
181 | } |
182 | |
183 | static void on_netinfo(struct most_interface *iface, |
184 | unsigned char link_stat, unsigned char *mac_addr); |
185 | |
186 | static int most_nd_open(struct net_device *dev) |
187 | { |
188 | struct net_dev_context *nd = netdev_priv(dev); |
189 | int ret = 0; |
190 | |
191 | mutex_lock(&probe_disc_mt); |
192 | |
193 | if (most_start_channel(iface: nd->iface, channel_idx: nd->rx.ch_id, comp: &comp)) { |
194 | netdev_err(dev, format: "most_start_channel() failed\n" ); |
195 | ret = -EBUSY; |
196 | goto unlock; |
197 | } |
198 | |
199 | if (most_start_channel(iface: nd->iface, channel_idx: nd->tx.ch_id, comp: &comp)) { |
200 | netdev_err(dev, format: "most_start_channel() failed\n" ); |
201 | most_stop_channel(iface: nd->iface, channel_idx: nd->rx.ch_id, comp: &comp); |
202 | ret = -EBUSY; |
203 | goto unlock; |
204 | } |
205 | |
206 | netif_carrier_off(dev); |
207 | if (is_valid_ether_addr(addr: dev->dev_addr)) |
208 | netif_dormant_off(dev); |
209 | else |
210 | netif_dormant_on(dev); |
211 | netif_wake_queue(dev); |
212 | if (nd->iface->request_netinfo) |
213 | nd->iface->request_netinfo(nd->iface, nd->tx.ch_id, on_netinfo); |
214 | |
215 | unlock: |
216 | mutex_unlock(lock: &probe_disc_mt); |
217 | return ret; |
218 | } |
219 | |
220 | static int most_nd_stop(struct net_device *dev) |
221 | { |
222 | struct net_dev_context *nd = netdev_priv(dev); |
223 | |
224 | netif_stop_queue(dev); |
225 | if (nd->iface->request_netinfo) |
226 | nd->iface->request_netinfo(nd->iface, nd->tx.ch_id, NULL); |
227 | most_stop_channel(iface: nd->iface, channel_idx: nd->rx.ch_id, comp: &comp); |
228 | most_stop_channel(iface: nd->iface, channel_idx: nd->tx.ch_id, comp: &comp); |
229 | |
230 | return 0; |
231 | } |
232 | |
233 | static netdev_tx_t most_nd_start_xmit(struct sk_buff *skb, |
234 | struct net_device *dev) |
235 | { |
236 | struct net_dev_context *nd = netdev_priv(dev); |
237 | struct mbo *mbo; |
238 | int ret; |
239 | |
240 | mbo = most_get_mbo(iface: nd->iface, channel_idx: nd->tx.ch_id, comp: &comp); |
241 | |
242 | if (!mbo) { |
243 | netif_stop_queue(dev); |
244 | dev->stats.tx_fifo_errors++; |
245 | return NETDEV_TX_BUSY; |
246 | } |
247 | |
248 | if (nd->is_mamac) |
249 | ret = skb_to_mamac(skb, mbo); |
250 | else |
251 | ret = skb_to_mep(skb, mbo); |
252 | |
253 | if (ret) { |
254 | most_put_mbo(mbo); |
255 | dev->stats.tx_dropped++; |
256 | kfree_skb(skb); |
257 | return NETDEV_TX_OK; |
258 | } |
259 | |
260 | most_submit_mbo(mbo); |
261 | dev->stats.tx_packets++; |
262 | dev->stats.tx_bytes += skb->len; |
263 | kfree_skb(skb); |
264 | return NETDEV_TX_OK; |
265 | } |
266 | |
267 | static const struct net_device_ops most_nd_ops = { |
268 | .ndo_open = most_nd_open, |
269 | .ndo_stop = most_nd_stop, |
270 | .ndo_start_xmit = most_nd_start_xmit, |
271 | .ndo_set_mac_address = most_nd_set_mac_address, |
272 | }; |
273 | |
274 | static void most_nd_setup(struct net_device *dev) |
275 | { |
276 | ether_setup(dev); |
277 | dev->netdev_ops = &most_nd_ops; |
278 | } |
279 | |
280 | static struct net_dev_context *get_net_dev(struct most_interface *iface) |
281 | { |
282 | struct net_dev_context *nd; |
283 | |
284 | list_for_each_entry(nd, &net_devices, list) |
285 | if (nd->iface == iface) |
286 | return nd; |
287 | return NULL; |
288 | } |
289 | |
290 | static struct net_dev_context *get_net_dev_hold(struct most_interface *iface) |
291 | { |
292 | struct net_dev_context *nd; |
293 | unsigned long flags; |
294 | |
295 | spin_lock_irqsave(&list_lock, flags); |
296 | nd = get_net_dev(iface); |
297 | if (nd && nd->rx.linked && nd->tx.linked) |
298 | dev_hold(dev: nd->dev); |
299 | else |
300 | nd = NULL; |
301 | spin_unlock_irqrestore(lock: &list_lock, flags); |
302 | return nd; |
303 | } |
304 | |
305 | static int comp_probe_channel(struct most_interface *iface, int channel_idx, |
306 | struct most_channel_config *ccfg, char *name, |
307 | char *args) |
308 | { |
309 | struct net_dev_context *nd; |
310 | struct net_dev_channel *ch; |
311 | struct net_device *dev; |
312 | unsigned long flags; |
313 | int ret = 0; |
314 | |
315 | if (!iface) |
316 | return -EINVAL; |
317 | |
318 | if (ccfg->data_type != MOST_CH_ASYNC) |
319 | return -EINVAL; |
320 | |
321 | mutex_lock(&probe_disc_mt); |
322 | nd = get_net_dev(iface); |
323 | if (!nd) { |
324 | dev = alloc_netdev(sizeof(struct net_dev_context), "meth%d" , |
325 | NET_NAME_UNKNOWN, most_nd_setup); |
326 | if (!dev) { |
327 | ret = -ENOMEM; |
328 | goto unlock; |
329 | } |
330 | |
331 | nd = netdev_priv(dev); |
332 | nd->iface = iface; |
333 | nd->dev = dev; |
334 | |
335 | spin_lock_irqsave(&list_lock, flags); |
336 | list_add(new: &nd->list, head: &net_devices); |
337 | spin_unlock_irqrestore(lock: &list_lock, flags); |
338 | |
339 | ch = ccfg->direction == MOST_CH_TX ? &nd->tx : &nd->rx; |
340 | } else { |
341 | ch = ccfg->direction == MOST_CH_TX ? &nd->tx : &nd->rx; |
342 | if (ch->linked) { |
343 | pr_err("direction is allocated\n" ); |
344 | ret = -EINVAL; |
345 | goto unlock; |
346 | } |
347 | |
348 | if (register_netdev(dev: nd->dev)) { |
349 | pr_err("register_netdev() failed\n" ); |
350 | ret = -EINVAL; |
351 | goto unlock; |
352 | } |
353 | } |
354 | ch->ch_id = channel_idx; |
355 | ch->linked = true; |
356 | |
357 | unlock: |
358 | mutex_unlock(lock: &probe_disc_mt); |
359 | return ret; |
360 | } |
361 | |
362 | static int comp_disconnect_channel(struct most_interface *iface, |
363 | int channel_idx) |
364 | { |
365 | struct net_dev_context *nd; |
366 | struct net_dev_channel *ch; |
367 | unsigned long flags; |
368 | int ret = 0; |
369 | |
370 | mutex_lock(&probe_disc_mt); |
371 | nd = get_net_dev(iface); |
372 | if (!nd) { |
373 | ret = -EINVAL; |
374 | goto unlock; |
375 | } |
376 | |
377 | if (nd->rx.linked && channel_idx == nd->rx.ch_id) { |
378 | ch = &nd->rx; |
379 | } else if (nd->tx.linked && channel_idx == nd->tx.ch_id) { |
380 | ch = &nd->tx; |
381 | } else { |
382 | ret = -EINVAL; |
383 | goto unlock; |
384 | } |
385 | |
386 | if (nd->rx.linked && nd->tx.linked) { |
387 | spin_lock_irqsave(&list_lock, flags); |
388 | ch->linked = false; |
389 | spin_unlock_irqrestore(lock: &list_lock, flags); |
390 | |
391 | /* |
392 | * do not call most_stop_channel() here, because channels are |
393 | * going to be closed in ndo_stop() after unregister_netdev() |
394 | */ |
395 | unregister_netdev(dev: nd->dev); |
396 | } else { |
397 | spin_lock_irqsave(&list_lock, flags); |
398 | list_del(entry: &nd->list); |
399 | spin_unlock_irqrestore(lock: &list_lock, flags); |
400 | |
401 | free_netdev(dev: nd->dev); |
402 | } |
403 | |
404 | unlock: |
405 | mutex_unlock(lock: &probe_disc_mt); |
406 | return ret; |
407 | } |
408 | |
409 | static int comp_resume_tx_channel(struct most_interface *iface, |
410 | int channel_idx) |
411 | { |
412 | struct net_dev_context *nd; |
413 | |
414 | nd = get_net_dev_hold(iface); |
415 | if (!nd) |
416 | return 0; |
417 | |
418 | if (nd->tx.ch_id != channel_idx) |
419 | goto put_nd; |
420 | |
421 | netif_wake_queue(dev: nd->dev); |
422 | |
423 | put_nd: |
424 | dev_put(dev: nd->dev); |
425 | return 0; |
426 | } |
427 | |
428 | static int comp_rx_data(struct mbo *mbo) |
429 | { |
430 | const u32 zero = 0; |
431 | struct net_dev_context *nd; |
432 | char *buf = mbo->virt_address; |
433 | u32 len = mbo->processed_length; |
434 | struct sk_buff *skb; |
435 | struct net_device *dev; |
436 | unsigned int skb_len; |
437 | int ret = 0; |
438 | |
439 | nd = get_net_dev_hold(iface: mbo->ifp); |
440 | if (!nd) |
441 | return -EIO; |
442 | |
443 | if (nd->rx.ch_id != mbo->hdm_channel_id) { |
444 | ret = -EIO; |
445 | goto put_nd; |
446 | } |
447 | |
448 | dev = nd->dev; |
449 | |
450 | if (nd->is_mamac) { |
451 | if (!pms_is_mamac(buf, len)) { |
452 | ret = -EIO; |
453 | goto put_nd; |
454 | } |
455 | |
456 | skb = dev_alloc_skb(length: len - MDP_HDR_LEN + 2 * ETH_ALEN + 2); |
457 | } else { |
458 | if (!PMS_IS_MEP(buf, len)) { |
459 | ret = -EIO; |
460 | goto put_nd; |
461 | } |
462 | |
463 | skb = dev_alloc_skb(length: len - MEP_HDR_LEN); |
464 | } |
465 | |
466 | if (!skb) { |
467 | dev->stats.rx_dropped++; |
468 | pr_err_once("drop packet: no memory for skb\n" ); |
469 | goto out; |
470 | } |
471 | |
472 | skb->dev = dev; |
473 | |
474 | if (nd->is_mamac) { |
475 | /* dest */ |
476 | ether_addr_copy(dst: skb_put(skb, ETH_ALEN), src: dev->dev_addr); |
477 | |
478 | /* src */ |
479 | skb_put_data(skb, data: &zero, len: 4); |
480 | skb_put_data(skb, data: buf + 5, len: 2); |
481 | |
482 | /* eth type */ |
483 | skb_put_data(skb, data: buf + 10, len: 2); |
484 | |
485 | buf += MDP_HDR_LEN; |
486 | len -= MDP_HDR_LEN; |
487 | } else { |
488 | buf += MEP_HDR_LEN; |
489 | len -= MEP_HDR_LEN; |
490 | } |
491 | |
492 | skb_put_data(skb, data: buf, len); |
493 | skb->protocol = eth_type_trans(skb, dev); |
494 | skb_len = skb->len; |
495 | if (netif_rx(skb) == NET_RX_SUCCESS) { |
496 | dev->stats.rx_packets++; |
497 | dev->stats.rx_bytes += skb_len; |
498 | } else { |
499 | dev->stats.rx_dropped++; |
500 | } |
501 | |
502 | out: |
503 | most_put_mbo(mbo); |
504 | |
505 | put_nd: |
506 | dev_put(dev: nd->dev); |
507 | return ret; |
508 | } |
509 | |
510 | static struct most_component comp = { |
511 | .mod = THIS_MODULE, |
512 | .name = "net" , |
513 | .probe_channel = comp_probe_channel, |
514 | .disconnect_channel = comp_disconnect_channel, |
515 | .tx_completion = comp_resume_tx_channel, |
516 | .rx_completion = comp_rx_data, |
517 | }; |
518 | |
519 | static int __init most_net_init(void) |
520 | { |
521 | int err; |
522 | |
523 | err = most_register_component(comp: &comp); |
524 | if (err) |
525 | return err; |
526 | err = most_register_configfs_subsys(comp: &comp); |
527 | if (err) { |
528 | most_deregister_component(comp: &comp); |
529 | return err; |
530 | } |
531 | return 0; |
532 | } |
533 | |
534 | static void __exit most_net_exit(void) |
535 | { |
536 | most_deregister_configfs_subsys(comp: &comp); |
537 | most_deregister_component(comp: &comp); |
538 | } |
539 | |
540 | /** |
541 | * on_netinfo - callback for HDM to be informed about HW's MAC |
542 | * @iface: most interface instance |
543 | * @link_stat: link status |
544 | * @mac_addr: MAC address |
545 | */ |
546 | static void on_netinfo(struct most_interface *iface, |
547 | unsigned char link_stat, unsigned char *mac_addr) |
548 | { |
549 | struct net_dev_context *nd; |
550 | struct net_device *dev; |
551 | const u8 *m = mac_addr; |
552 | |
553 | nd = get_net_dev_hold(iface); |
554 | if (!nd) |
555 | return; |
556 | |
557 | dev = nd->dev; |
558 | |
559 | if (link_stat) |
560 | netif_carrier_on(dev); |
561 | else |
562 | netif_carrier_off(dev); |
563 | |
564 | if (m && is_valid_ether_addr(addr: m)) { |
565 | if (!is_valid_ether_addr(addr: dev->dev_addr)) { |
566 | netdev_info(dev, format: "set mac %pM\n" , m); |
567 | eth_hw_addr_set(dev, addr: m); |
568 | netif_dormant_off(dev); |
569 | } else if (!ether_addr_equal(addr1: dev->dev_addr, addr2: m)) { |
570 | netdev_warn(dev, format: "reject mac %pM\n" , m); |
571 | } |
572 | } |
573 | |
574 | dev_put(dev: nd->dev); |
575 | } |
576 | |
577 | module_init(most_net_init); |
578 | module_exit(most_net_exit); |
579 | MODULE_LICENSE("GPL" ); |
580 | MODULE_AUTHOR("Andrey Shvetsov <andrey.shvetsov@k2l.de>" ); |
581 | MODULE_DESCRIPTION("Networking Component Module for Mostcore" ); |
582 | |