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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * net/dsa/dsa.c - Hardware switch handling
4 * Copyright (c) 2008-2009 Marvell Semiconductor
5 * Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>
6 */
7
8#include <linux/device.h>
9#include <linux/list.h>
10#include <linux/platform_device.h>
11#include <linux/slab.h>
12#include <linux/module.h>
13#include <linux/notifier.h>
14#include <linux/of.h>
15#include <linux/of_mdio.h>
16#include <linux/of_platform.h>
17#include <linux/of_net.h>
18#include <linux/netdevice.h>
19#include <linux/sysfs.h>
20#include <linux/phy_fixed.h>
21#include <linux/ptp_classify.h>
22#include <linux/etherdevice.h>
23
24#include "dsa_priv.h"
25
26static LIST_HEAD(dsa_tag_drivers_list);
27static DEFINE_MUTEX(dsa_tag_drivers_lock);
28
29static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
30 struct net_device *dev)
31{
32 /* Just return the original SKB */
33 return skb;
34}
35
36static const struct dsa_device_ops none_ops = {
37 .name = "none",
38 .proto = DSA_TAG_PROTO_NONE,
39 .xmit = dsa_slave_notag_xmit,
40 .rcv = NULL,
41};
42
43DSA_TAG_DRIVER(none_ops);
44
45static void dsa_tag_driver_register(struct dsa_tag_driver *dsa_tag_driver,
46 struct module *owner)
47{
48 dsa_tag_driver->owner = owner;
49
50 mutex_lock(&dsa_tag_drivers_lock);
51 list_add_tail(&dsa_tag_driver->list, &dsa_tag_drivers_list);
52 mutex_unlock(&dsa_tag_drivers_lock);
53}
54
55void dsa_tag_drivers_register(struct dsa_tag_driver *dsa_tag_driver_array[],
56 unsigned int count, struct module *owner)
57{
58 unsigned int i;
59
60 for (i = 0; i < count; i++)
61 dsa_tag_driver_register(dsa_tag_driver_array[i], owner);
62}
63
64static void dsa_tag_driver_unregister(struct dsa_tag_driver *dsa_tag_driver)
65{
66 mutex_lock(&dsa_tag_drivers_lock);
67 list_del(&dsa_tag_driver->list);
68 mutex_unlock(&dsa_tag_drivers_lock);
69}
70EXPORT_SYMBOL_GPL(dsa_tag_drivers_register);
71
72void dsa_tag_drivers_unregister(struct dsa_tag_driver *dsa_tag_driver_array[],
73 unsigned int count)
74{
75 unsigned int i;
76
77 for (i = 0; i < count; i++)
78 dsa_tag_driver_unregister(dsa_tag_driver_array[i]);
79}
80EXPORT_SYMBOL_GPL(dsa_tag_drivers_unregister);
81
82const char *dsa_tag_protocol_to_str(const struct dsa_device_ops *ops)
83{
84 return ops->name;
85};
86
87const struct dsa_device_ops *dsa_tag_driver_get(int tag_protocol)
88{
89 struct dsa_tag_driver *dsa_tag_driver;
90 const struct dsa_device_ops *ops;
91 char module_name[128];
92 bool found = false;
93
94 snprintf(module_name, 127, "%s%d", DSA_TAG_DRIVER_ALIAS,
95 tag_protocol);
96
97 request_module(module_name);
98
99 mutex_lock(&dsa_tag_drivers_lock);
100 list_for_each_entry(dsa_tag_driver, &dsa_tag_drivers_list, list) {
101 ops = dsa_tag_driver->ops;
102 if (ops->proto == tag_protocol) {
103 found = true;
104 break;
105 }
106 }
107
108 if (found) {
109 if (!try_module_get(dsa_tag_driver->owner))
110 ops = ERR_PTR(-ENOPROTOOPT);
111 } else {
112 ops = ERR_PTR(-ENOPROTOOPT);
113 }
114
115 mutex_unlock(&dsa_tag_drivers_lock);
116
117 return ops;
118}
119
120void dsa_tag_driver_put(const struct dsa_device_ops *ops)
121{
122 struct dsa_tag_driver *dsa_tag_driver;
123
124 mutex_lock(&dsa_tag_drivers_lock);
125 list_for_each_entry(dsa_tag_driver, &dsa_tag_drivers_list, list) {
126 if (dsa_tag_driver->ops == ops) {
127 module_put(dsa_tag_driver->owner);
128 break;
129 }
130 }
131 mutex_unlock(&dsa_tag_drivers_lock);
132}
133
134static int dev_is_class(struct device *dev, void *class)
135{
136 if (dev->class != NULL && !strcmp(dev->class->name, class))
137 return 1;
138
139 return 0;
140}
141
142static struct device *dev_find_class(struct device *parent, char *class)
143{
144 if (dev_is_class(parent, class)) {
145 get_device(parent);
146 return parent;
147 }
148
149 return device_find_child(parent, class, dev_is_class);
150}
151
152struct net_device *dsa_dev_to_net_device(struct device *dev)
153{
154 struct device *d;
155
156 d = dev_find_class(dev, "net");
157 if (d != NULL) {
158 struct net_device *nd;
159
160 nd = to_net_dev(d);
161 dev_hold(nd);
162 put_device(d);
163
164 return nd;
165 }
166
167 return NULL;
168}
169EXPORT_SYMBOL_GPL(dsa_dev_to_net_device);
170
171/* Determine if we should defer delivery of skb until we have a rx timestamp.
172 *
173 * Called from dsa_switch_rcv. For now, this will only work if tagging is
174 * enabled on the switch. Normally the MAC driver would retrieve the hardware
175 * timestamp when it reads the packet out of the hardware. However in a DSA
176 * switch, the DSA driver owning the interface to which the packet is
177 * delivered is never notified unless we do so here.
178 */
179static bool dsa_skb_defer_rx_timestamp(struct dsa_slave_priv *p,
180 struct sk_buff *skb)
181{
182 struct dsa_switch *ds = p->dp->ds;
183 unsigned int type;
184
185 if (skb_headroom(skb) < ETH_HLEN)
186 return false;
187
188 __skb_push(skb, ETH_HLEN);
189
190 type = ptp_classify_raw(skb);
191
192 __skb_pull(skb, ETH_HLEN);
193
194 if (type == PTP_CLASS_NONE)
195 return false;
196
197 if (likely(ds->ops->port_rxtstamp))
198 return ds->ops->port_rxtstamp(ds, p->dp->index, skb, type);
199
200 return false;
201}
202
203static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
204 struct packet_type *pt, struct net_device *unused)
205{
206 struct dsa_port *cpu_dp = dev->dsa_ptr;
207 struct sk_buff *nskb = NULL;
208 struct pcpu_sw_netstats *s;
209 struct dsa_slave_priv *p;
210
211 if (unlikely(!cpu_dp)) {
212 kfree_skb(skb);
213 return 0;
214 }
215
216 skb = skb_unshare(skb, GFP_ATOMIC);
217 if (!skb)
218 return 0;
219
220 nskb = cpu_dp->rcv(skb, dev, pt);
221 if (!nskb) {
222 kfree_skb(skb);
223 return 0;
224 }
225
226 skb = nskb;
227 p = netdev_priv(skb->dev);
228 skb_push(skb, ETH_HLEN);
229 skb->pkt_type = PACKET_HOST;
230 skb->protocol = eth_type_trans(skb, skb->dev);
231
232 s = this_cpu_ptr(p->stats64);
233 u64_stats_update_begin(&s->syncp);
234 s->rx_packets++;
235 s->rx_bytes += skb->len;
236 u64_stats_update_end(&s->syncp);
237
238 if (dsa_skb_defer_rx_timestamp(p, skb))
239 return 0;
240
241 netif_receive_skb(skb);
242
243 return 0;
244}
245
246#ifdef CONFIG_PM_SLEEP
247static bool dsa_is_port_initialized(struct dsa_switch *ds, int p)
248{
249 return dsa_is_user_port(ds, p) && ds->ports[p].slave;
250}
251
252int dsa_switch_suspend(struct dsa_switch *ds)
253{
254 int i, ret = 0;
255
256 /* Suspend slave network devices */
257 for (i = 0; i < ds->num_ports; i++) {
258 if (!dsa_is_port_initialized(ds, i))
259 continue;
260
261 ret = dsa_slave_suspend(ds->ports[i].slave);
262 if (ret)
263 return ret;
264 }
265
266 if (ds->ops->suspend)
267 ret = ds->ops->suspend(ds);
268
269 return ret;
270}
271EXPORT_SYMBOL_GPL(dsa_switch_suspend);
272
273int dsa_switch_resume(struct dsa_switch *ds)
274{
275 int i, ret = 0;
276
277 if (ds->ops->resume)
278 ret = ds->ops->resume(ds);
279
280 if (ret)
281 return ret;
282
283 /* Resume slave network devices */
284 for (i = 0; i < ds->num_ports; i++) {
285 if (!dsa_is_port_initialized(ds, i))
286 continue;
287
288 ret = dsa_slave_resume(ds->ports[i].slave);
289 if (ret)
290 return ret;
291 }
292
293 return 0;
294}
295EXPORT_SYMBOL_GPL(dsa_switch_resume);
296#endif
297
298static struct packet_type dsa_pack_type __read_mostly = {
299 .type = cpu_to_be16(ETH_P_XDSA),
300 .func = dsa_switch_rcv,
301};
302
303static struct workqueue_struct *dsa_owq;
304
305bool dsa_schedule_work(struct work_struct *work)
306{
307 return queue_work(dsa_owq, work);
308}
309
310static ATOMIC_NOTIFIER_HEAD(dsa_notif_chain);
311
312int register_dsa_notifier(struct notifier_block *nb)
313{
314 return atomic_notifier_chain_register(&dsa_notif_chain, nb);
315}
316EXPORT_SYMBOL_GPL(register_dsa_notifier);
317
318int unregister_dsa_notifier(struct notifier_block *nb)
319{
320 return atomic_notifier_chain_unregister(&dsa_notif_chain, nb);
321}
322EXPORT_SYMBOL_GPL(unregister_dsa_notifier);
323
324int call_dsa_notifiers(unsigned long val, struct net_device *dev,
325 struct dsa_notifier_info *info)
326{
327 info->dev = dev;
328 return atomic_notifier_call_chain(&dsa_notif_chain, val, info);
329}
330EXPORT_SYMBOL_GPL(call_dsa_notifiers);
331
332static int __init dsa_init_module(void)
333{
334 int rc;
335
336 dsa_owq = alloc_ordered_workqueue("dsa_ordered",
337 WQ_MEM_RECLAIM);
338 if (!dsa_owq)
339 return -ENOMEM;
340
341 rc = dsa_slave_register_notifier();
342 if (rc)
343 goto register_notifier_fail;
344
345 dev_add_pack(&dsa_pack_type);
346
347 dsa_tag_driver_register(&DSA_TAG_DRIVER_NAME(none_ops),
348 THIS_MODULE);
349
350 return 0;
351
352register_notifier_fail:
353 destroy_workqueue(dsa_owq);
354
355 return rc;
356}
357module_init(dsa_init_module);
358
359static void __exit dsa_cleanup_module(void)
360{
361 dsa_tag_driver_unregister(&DSA_TAG_DRIVER_NAME(none_ops));
362
363 dsa_slave_unregister_notifier();
364 dev_remove_pack(&dsa_pack_type);
365 destroy_workqueue(dsa_owq);
366}
367module_exit(dsa_cleanup_module);
368
369MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
370MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
371MODULE_LICENSE("GPL");
372MODULE_ALIAS("platform:dsa");
1/*
2 * net/dsa/dsa.c - Hardware switch handling
3 * Copyright (c) 2008-2009 Marvell Semiconductor
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
9 */
10
11#include <linux/list.h>
12#include <linux/netdevice.h>
13#include <linux/platform_device.h>
14#include <linux/slab.h>
15#include <net/dsa.h>
16#include "dsa_priv.h"
17
18char dsa_driver_version[] = "0.1";
19
20
21/* switch driver registration ***********************************************/
22static DEFINE_MUTEX(dsa_switch_drivers_mutex);
23static LIST_HEAD(dsa_switch_drivers);
24
25void register_switch_driver(struct dsa_switch_driver *drv)
26{
27 mutex_lock(&dsa_switch_drivers_mutex);
28 list_add_tail(&drv->list, &dsa_switch_drivers);
29 mutex_unlock(&dsa_switch_drivers_mutex);
30}
31
32void unregister_switch_driver(struct dsa_switch_driver *drv)
33{
34 mutex_lock(&dsa_switch_drivers_mutex);
35 list_del_init(&drv->list);
36 mutex_unlock(&dsa_switch_drivers_mutex);
37}
38
39static struct dsa_switch_driver *
40dsa_switch_probe(struct mii_bus *bus, int sw_addr, char **_name)
41{
42 struct dsa_switch_driver *ret;
43 struct list_head *list;
44 char *name;
45
46 ret = NULL;
47 name = NULL;
48
49 mutex_lock(&dsa_switch_drivers_mutex);
50 list_for_each(list, &dsa_switch_drivers) {
51 struct dsa_switch_driver *drv;
52
53 drv = list_entry(list, struct dsa_switch_driver, list);
54
55 name = drv->probe(bus, sw_addr);
56 if (name != NULL) {
57 ret = drv;
58 break;
59 }
60 }
61 mutex_unlock(&dsa_switch_drivers_mutex);
62
63 *_name = name;
64
65 return ret;
66}
67
68
69/* basic switch operations **************************************************/
70static struct dsa_switch *
71dsa_switch_setup(struct dsa_switch_tree *dst, int index,
72 struct device *parent, struct mii_bus *bus)
73{
74 struct dsa_chip_data *pd = dst->pd->chip + index;
75 struct dsa_switch_driver *drv;
76 struct dsa_switch *ds;
77 int ret;
78 char *name;
79 int i;
80
81 /*
82 * Probe for switch model.
83 */
84 drv = dsa_switch_probe(bus, pd->sw_addr, &name);
85 if (drv == NULL) {
86 printk(KERN_ERR "%s[%d]: could not detect attached switch\n",
87 dst->master_netdev->name, index);
88 return ERR_PTR(-EINVAL);
89 }
90 printk(KERN_INFO "%s[%d]: detected a %s switch\n",
91 dst->master_netdev->name, index, name);
92
93
94 /*
95 * Allocate and initialise switch state.
96 */
97 ds = kzalloc(sizeof(*ds) + drv->priv_size, GFP_KERNEL);
98 if (ds == NULL)
99 return ERR_PTR(-ENOMEM);
100
101 ds->dst = dst;
102 ds->index = index;
103 ds->pd = dst->pd->chip + index;
104 ds->drv = drv;
105 ds->master_mii_bus = bus;
106
107
108 /*
109 * Validate supplied switch configuration.
110 */
111 for (i = 0; i < DSA_MAX_PORTS; i++) {
112 char *name;
113
114 name = pd->port_names[i];
115 if (name == NULL)
116 continue;
117
118 if (!strcmp(name, "cpu")) {
119 if (dst->cpu_switch != -1) {
120 printk(KERN_ERR "multiple cpu ports?!\n");
121 ret = -EINVAL;
122 goto out;
123 }
124 dst->cpu_switch = index;
125 dst->cpu_port = i;
126 } else if (!strcmp(name, "dsa")) {
127 ds->dsa_port_mask |= 1 << i;
128 } else {
129 ds->phys_port_mask |= 1 << i;
130 }
131 }
132
133
134 /*
135 * If the CPU connects to this switch, set the switch tree
136 * tagging protocol to the preferred tagging format of this
137 * switch.
138 */
139 if (ds->dst->cpu_switch == index)
140 ds->dst->tag_protocol = drv->tag_protocol;
141
142
143 /*
144 * Do basic register setup.
145 */
146 ret = drv->setup(ds);
147 if (ret < 0)
148 goto out;
149
150 ret = drv->set_addr(ds, dst->master_netdev->dev_addr);
151 if (ret < 0)
152 goto out;
153
154 ds->slave_mii_bus = mdiobus_alloc();
155 if (ds->slave_mii_bus == NULL) {
156 ret = -ENOMEM;
157 goto out;
158 }
159 dsa_slave_mii_bus_init(ds);
160
161 ret = mdiobus_register(ds->slave_mii_bus);
162 if (ret < 0)
163 goto out_free;
164
165
166 /*
167 * Create network devices for physical switch ports.
168 */
169 for (i = 0; i < DSA_MAX_PORTS; i++) {
170 struct net_device *slave_dev;
171
172 if (!(ds->phys_port_mask & (1 << i)))
173 continue;
174
175 slave_dev = dsa_slave_create(ds, parent, i, pd->port_names[i]);
176 if (slave_dev == NULL) {
177 printk(KERN_ERR "%s[%d]: can't create dsa "
178 "slave device for port %d(%s)\n",
179 dst->master_netdev->name,
180 index, i, pd->port_names[i]);
181 continue;
182 }
183
184 ds->ports[i] = slave_dev;
185 }
186
187 return ds;
188
189out_free:
190 mdiobus_free(ds->slave_mii_bus);
191out:
192 kfree(ds);
193 return ERR_PTR(ret);
194}
195
196static void dsa_switch_destroy(struct dsa_switch *ds)
197{
198}
199
200
201/* hooks for ethertype-less tagging formats *********************************/
202/*
203 * The original DSA tag format and some other tag formats have no
204 * ethertype, which means that we need to add a little hack to the
205 * networking receive path to make sure that received frames get
206 * the right ->protocol assigned to them when one of those tag
207 * formats is in use.
208 */
209bool dsa_uses_dsa_tags(void *dsa_ptr)
210{
211 struct dsa_switch_tree *dst = dsa_ptr;
212
213 return !!(dst->tag_protocol == htons(ETH_P_DSA));
214}
215
216bool dsa_uses_trailer_tags(void *dsa_ptr)
217{
218 struct dsa_switch_tree *dst = dsa_ptr;
219
220 return !!(dst->tag_protocol == htons(ETH_P_TRAILER));
221}
222
223
224/* link polling *************************************************************/
225static void dsa_link_poll_work(struct work_struct *ugly)
226{
227 struct dsa_switch_tree *dst;
228 int i;
229
230 dst = container_of(ugly, struct dsa_switch_tree, link_poll_work);
231
232 for (i = 0; i < dst->pd->nr_chips; i++) {
233 struct dsa_switch *ds = dst->ds[i];
234
235 if (ds != NULL && ds->drv->poll_link != NULL)
236 ds->drv->poll_link(ds);
237 }
238
239 mod_timer(&dst->link_poll_timer, round_jiffies(jiffies + HZ));
240}
241
242static void dsa_link_poll_timer(unsigned long _dst)
243{
244 struct dsa_switch_tree *dst = (void *)_dst;
245
246 schedule_work(&dst->link_poll_work);
247}
248
249
250/* platform driver init and cleanup *****************************************/
251static int dev_is_class(struct device *dev, void *class)
252{
253 if (dev->class != NULL && !strcmp(dev->class->name, class))
254 return 1;
255
256 return 0;
257}
258
259static struct device *dev_find_class(struct device *parent, char *class)
260{
261 if (dev_is_class(parent, class)) {
262 get_device(parent);
263 return parent;
264 }
265
266 return device_find_child(parent, class, dev_is_class);
267}
268
269static struct mii_bus *dev_to_mii_bus(struct device *dev)
270{
271 struct device *d;
272
273 d = dev_find_class(dev, "mdio_bus");
274 if (d != NULL) {
275 struct mii_bus *bus;
276
277 bus = to_mii_bus(d);
278 put_device(d);
279
280 return bus;
281 }
282
283 return NULL;
284}
285
286static struct net_device *dev_to_net_device(struct device *dev)
287{
288 struct device *d;
289
290 d = dev_find_class(dev, "net");
291 if (d != NULL) {
292 struct net_device *nd;
293
294 nd = to_net_dev(d);
295 dev_hold(nd);
296 put_device(d);
297
298 return nd;
299 }
300
301 return NULL;
302}
303
304static int dsa_probe(struct platform_device *pdev)
305{
306 static int dsa_version_printed;
307 struct dsa_platform_data *pd = pdev->dev.platform_data;
308 struct net_device *dev;
309 struct dsa_switch_tree *dst;
310 int i;
311
312 if (!dsa_version_printed++)
313 printk(KERN_NOTICE "Distributed Switch Architecture "
314 "driver version %s\n", dsa_driver_version);
315
316 if (pd == NULL || pd->netdev == NULL)
317 return -EINVAL;
318
319 dev = dev_to_net_device(pd->netdev);
320 if (dev == NULL)
321 return -EINVAL;
322
323 if (dev->dsa_ptr != NULL) {
324 dev_put(dev);
325 return -EEXIST;
326 }
327
328 dst = kzalloc(sizeof(*dst), GFP_KERNEL);
329 if (dst == NULL) {
330 dev_put(dev);
331 return -ENOMEM;
332 }
333
334 platform_set_drvdata(pdev, dst);
335
336 dst->pd = pd;
337 dst->master_netdev = dev;
338 dst->cpu_switch = -1;
339 dst->cpu_port = -1;
340
341 for (i = 0; i < pd->nr_chips; i++) {
342 struct mii_bus *bus;
343 struct dsa_switch *ds;
344
345 bus = dev_to_mii_bus(pd->chip[i].mii_bus);
346 if (bus == NULL) {
347 printk(KERN_ERR "%s[%d]: no mii bus found for "
348 "dsa switch\n", dev->name, i);
349 continue;
350 }
351
352 ds = dsa_switch_setup(dst, i, &pdev->dev, bus);
353 if (IS_ERR(ds)) {
354 printk(KERN_ERR "%s[%d]: couldn't create dsa switch "
355 "instance (error %ld)\n", dev->name, i,
356 PTR_ERR(ds));
357 continue;
358 }
359
360 dst->ds[i] = ds;
361 if (ds->drv->poll_link != NULL)
362 dst->link_poll_needed = 1;
363 }
364
365 /*
366 * If we use a tagging format that doesn't have an ethertype
367 * field, make sure that all packets from this point on get
368 * sent to the tag format's receive function.
369 */
370 wmb();
371 dev->dsa_ptr = (void *)dst;
372
373 if (dst->link_poll_needed) {
374 INIT_WORK(&dst->link_poll_work, dsa_link_poll_work);
375 init_timer(&dst->link_poll_timer);
376 dst->link_poll_timer.data = (unsigned long)dst;
377 dst->link_poll_timer.function = dsa_link_poll_timer;
378 dst->link_poll_timer.expires = round_jiffies(jiffies + HZ);
379 add_timer(&dst->link_poll_timer);
380 }
381
382 return 0;
383}
384
385static int dsa_remove(struct platform_device *pdev)
386{
387 struct dsa_switch_tree *dst = platform_get_drvdata(pdev);
388 int i;
389
390 if (dst->link_poll_needed)
391 del_timer_sync(&dst->link_poll_timer);
392
393 flush_work_sync(&dst->link_poll_work);
394
395 for (i = 0; i < dst->pd->nr_chips; i++) {
396 struct dsa_switch *ds = dst->ds[i];
397
398 if (ds != NULL)
399 dsa_switch_destroy(ds);
400 }
401
402 return 0;
403}
404
405static void dsa_shutdown(struct platform_device *pdev)
406{
407}
408
409static struct platform_driver dsa_driver = {
410 .probe = dsa_probe,
411 .remove = dsa_remove,
412 .shutdown = dsa_shutdown,
413 .driver = {
414 .name = "dsa",
415 .owner = THIS_MODULE,
416 },
417};
418
419static int __init dsa_init_module(void)
420{
421 return platform_driver_register(&dsa_driver);
422}
423module_init(dsa_init_module);
424
425static void __exit dsa_cleanup_module(void)
426{
427 platform_driver_unregister(&dsa_driver);
428}
429module_exit(dsa_cleanup_module);
430
431MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
432MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
433MODULE_LICENSE("GPL");
434MODULE_ALIAS("platform:dsa");