xref: /openbmc/linux/net/dsa/dsa.c (revision 4a3fad70)
1 /*
2  * net/dsa/dsa.c - Hardware switch handling
3  * Copyright (c) 2008-2009 Marvell Semiconductor
4  * Copyright (c) 2013 Florian Fainelli <florian@openwrt.org>
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  */
11 
12 #include <linux/device.h>
13 #include <linux/list.h>
14 #include <linux/platform_device.h>
15 #include <linux/slab.h>
16 #include <linux/module.h>
17 #include <linux/notifier.h>
18 #include <linux/of.h>
19 #include <linux/of_mdio.h>
20 #include <linux/of_platform.h>
21 #include <linux/of_net.h>
22 #include <linux/of_gpio.h>
23 #include <linux/netdevice.h>
24 #include <linux/sysfs.h>
25 #include <linux/phy_fixed.h>
26 #include <linux/gpio/consumer.h>
27 #include <linux/etherdevice.h>
28 
29 #include "dsa_priv.h"
30 
31 static struct sk_buff *dsa_slave_notag_xmit(struct sk_buff *skb,
32 					    struct net_device *dev)
33 {
34 	/* Just return the original SKB */
35 	return skb;
36 }
37 
38 static const struct dsa_device_ops none_ops = {
39 	.xmit	= dsa_slave_notag_xmit,
40 	.rcv	= NULL,
41 };
42 
43 const struct dsa_device_ops *dsa_device_ops[DSA_TAG_LAST] = {
44 #ifdef CONFIG_NET_DSA_TAG_BRCM
45 	[DSA_TAG_PROTO_BRCM] = &brcm_netdev_ops,
46 #endif
47 #ifdef CONFIG_NET_DSA_TAG_BRCM_PREPEND
48 	[DSA_TAG_PROTO_BRCM_PREPEND] = &brcm_prepend_netdev_ops,
49 #endif
50 #ifdef CONFIG_NET_DSA_TAG_DSA
51 	[DSA_TAG_PROTO_DSA] = &dsa_netdev_ops,
52 #endif
53 #ifdef CONFIG_NET_DSA_TAG_EDSA
54 	[DSA_TAG_PROTO_EDSA] = &edsa_netdev_ops,
55 #endif
56 #ifdef CONFIG_NET_DSA_TAG_KSZ
57 	[DSA_TAG_PROTO_KSZ] = &ksz_netdev_ops,
58 #endif
59 #ifdef CONFIG_NET_DSA_TAG_LAN9303
60 	[DSA_TAG_PROTO_LAN9303] = &lan9303_netdev_ops,
61 #endif
62 #ifdef CONFIG_NET_DSA_TAG_MTK
63 	[DSA_TAG_PROTO_MTK] = &mtk_netdev_ops,
64 #endif
65 #ifdef CONFIG_NET_DSA_TAG_QCA
66 	[DSA_TAG_PROTO_QCA] = &qca_netdev_ops,
67 #endif
68 #ifdef CONFIG_NET_DSA_TAG_TRAILER
69 	[DSA_TAG_PROTO_TRAILER] = &trailer_netdev_ops,
70 #endif
71 	[DSA_TAG_PROTO_NONE] = &none_ops,
72 };
73 
74 const struct dsa_device_ops *dsa_resolve_tag_protocol(int tag_protocol)
75 {
76 	const struct dsa_device_ops *ops;
77 
78 	if (tag_protocol >= DSA_TAG_LAST)
79 		return ERR_PTR(-EINVAL);
80 	ops = dsa_device_ops[tag_protocol];
81 
82 	if (!ops)
83 		return ERR_PTR(-ENOPROTOOPT);
84 
85 	return ops;
86 }
87 
88 static int dev_is_class(struct device *dev, void *class)
89 {
90 	if (dev->class != NULL && !strcmp(dev->class->name, class))
91 		return 1;
92 
93 	return 0;
94 }
95 
96 static struct device *dev_find_class(struct device *parent, char *class)
97 {
98 	if (dev_is_class(parent, class)) {
99 		get_device(parent);
100 		return parent;
101 	}
102 
103 	return device_find_child(parent, class, dev_is_class);
104 }
105 
106 struct net_device *dsa_dev_to_net_device(struct device *dev)
107 {
108 	struct device *d;
109 
110 	d = dev_find_class(dev, "net");
111 	if (d != NULL) {
112 		struct net_device *nd;
113 
114 		nd = to_net_dev(d);
115 		dev_hold(nd);
116 		put_device(d);
117 
118 		return nd;
119 	}
120 
121 	return NULL;
122 }
123 EXPORT_SYMBOL_GPL(dsa_dev_to_net_device);
124 
125 static int dsa_switch_rcv(struct sk_buff *skb, struct net_device *dev,
126 			  struct packet_type *pt, struct net_device *unused)
127 {
128 	struct dsa_port *cpu_dp = dev->dsa_ptr;
129 	struct sk_buff *nskb = NULL;
130 	struct pcpu_sw_netstats *s;
131 	struct dsa_slave_priv *p;
132 
133 	if (unlikely(!cpu_dp)) {
134 		kfree_skb(skb);
135 		return 0;
136 	}
137 
138 	skb = skb_unshare(skb, GFP_ATOMIC);
139 	if (!skb)
140 		return 0;
141 
142 	nskb = cpu_dp->rcv(skb, dev, pt);
143 	if (!nskb) {
144 		kfree_skb(skb);
145 		return 0;
146 	}
147 
148 	skb = nskb;
149 	p = netdev_priv(skb->dev);
150 	skb_push(skb, ETH_HLEN);
151 	skb->pkt_type = PACKET_HOST;
152 	skb->protocol = eth_type_trans(skb, skb->dev);
153 
154 	s = this_cpu_ptr(p->stats64);
155 	u64_stats_update_begin(&s->syncp);
156 	s->rx_packets++;
157 	s->rx_bytes += skb->len;
158 	u64_stats_update_end(&s->syncp);
159 
160 	netif_receive_skb(skb);
161 
162 	return 0;
163 }
164 
165 #ifdef CONFIG_PM_SLEEP
166 static bool dsa_is_port_initialized(struct dsa_switch *ds, int p)
167 {
168 	return dsa_is_user_port(ds, p) && ds->ports[p].slave;
169 }
170 
171 int dsa_switch_suspend(struct dsa_switch *ds)
172 {
173 	int i, ret = 0;
174 
175 	/* Suspend slave network devices */
176 	for (i = 0; i < ds->num_ports; i++) {
177 		if (!dsa_is_port_initialized(ds, i))
178 			continue;
179 
180 		ret = dsa_slave_suspend(ds->ports[i].slave);
181 		if (ret)
182 			return ret;
183 	}
184 
185 	if (ds->ops->suspend)
186 		ret = ds->ops->suspend(ds);
187 
188 	return ret;
189 }
190 EXPORT_SYMBOL_GPL(dsa_switch_suspend);
191 
192 int dsa_switch_resume(struct dsa_switch *ds)
193 {
194 	int i, ret = 0;
195 
196 	if (ds->ops->resume)
197 		ret = ds->ops->resume(ds);
198 
199 	if (ret)
200 		return ret;
201 
202 	/* Resume slave network devices */
203 	for (i = 0; i < ds->num_ports; i++) {
204 		if (!dsa_is_port_initialized(ds, i))
205 			continue;
206 
207 		ret = dsa_slave_resume(ds->ports[i].slave);
208 		if (ret)
209 			return ret;
210 	}
211 
212 	return 0;
213 }
214 EXPORT_SYMBOL_GPL(dsa_switch_resume);
215 #endif
216 
217 static struct packet_type dsa_pack_type __read_mostly = {
218 	.type	= cpu_to_be16(ETH_P_XDSA),
219 	.func	= dsa_switch_rcv,
220 };
221 
222 static struct workqueue_struct *dsa_owq;
223 
224 bool dsa_schedule_work(struct work_struct *work)
225 {
226 	return queue_work(dsa_owq, work);
227 }
228 
229 static ATOMIC_NOTIFIER_HEAD(dsa_notif_chain);
230 
231 int register_dsa_notifier(struct notifier_block *nb)
232 {
233 	return atomic_notifier_chain_register(&dsa_notif_chain, nb);
234 }
235 EXPORT_SYMBOL_GPL(register_dsa_notifier);
236 
237 int unregister_dsa_notifier(struct notifier_block *nb)
238 {
239 	return atomic_notifier_chain_unregister(&dsa_notif_chain, nb);
240 }
241 EXPORT_SYMBOL_GPL(unregister_dsa_notifier);
242 
243 int call_dsa_notifiers(unsigned long val, struct net_device *dev,
244 		       struct dsa_notifier_info *info)
245 {
246 	info->dev = dev;
247 	return atomic_notifier_call_chain(&dsa_notif_chain, val, info);
248 }
249 EXPORT_SYMBOL_GPL(call_dsa_notifiers);
250 
251 static int __init dsa_init_module(void)
252 {
253 	int rc;
254 
255 	dsa_owq = alloc_ordered_workqueue("dsa_ordered",
256 					  WQ_MEM_RECLAIM);
257 	if (!dsa_owq)
258 		return -ENOMEM;
259 
260 	rc = dsa_slave_register_notifier();
261 	if (rc)
262 		return rc;
263 
264 	rc = dsa_legacy_register();
265 	if (rc)
266 		return rc;
267 
268 	dev_add_pack(&dsa_pack_type);
269 
270 	return 0;
271 }
272 module_init(dsa_init_module);
273 
274 static void __exit dsa_cleanup_module(void)
275 {
276 	dsa_slave_unregister_notifier();
277 	dev_remove_pack(&dsa_pack_type);
278 	dsa_legacy_unregister();
279 	destroy_workqueue(dsa_owq);
280 }
281 module_exit(dsa_cleanup_module);
282 
283 MODULE_AUTHOR("Lennert Buytenhek <buytenh@wantstofly.org>");
284 MODULE_DESCRIPTION("Driver for Distributed Switch Architecture switch chips");
285 MODULE_LICENSE("GPL");
286 MODULE_ALIAS("platform:dsa");
287