xref: /openbmc/linux/drivers/net/dsa/dsa_loop.c (revision 2eb3ed33e55d003d721d4d1a5e72fe323c12b4c0)
1 /*
2  * Distributed Switch Architecture loopback driver
3  *
4  * Copyright (C) 2016, Florian Fainelli <f.fainelli@gmail.com>
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/platform_device.h>
13 #include <linux/netdevice.h>
14 #include <linux/phy.h>
15 #include <linux/phy_fixed.h>
16 #include <linux/export.h>
17 #include <linux/ethtool.h>
18 #include <linux/workqueue.h>
19 #include <linux/module.h>
20 #include <linux/if_bridge.h>
21 #include <net/dsa.h>
22 
23 #include "dsa_loop.h"
24 
25 struct dsa_loop_vlan {
26 	u16 members;
27 	u16 untagged;
28 };
29 
30 struct dsa_loop_mib_entry {
31 	char name[ETH_GSTRING_LEN];
32 	unsigned long val;
33 };
34 
35 enum dsa_loop_mib_counters {
36 	DSA_LOOP_PHY_READ_OK,
37 	DSA_LOOP_PHY_READ_ERR,
38 	DSA_LOOP_PHY_WRITE_OK,
39 	DSA_LOOP_PHY_WRITE_ERR,
40 	__DSA_LOOP_CNT_MAX,
41 };
42 
43 static struct dsa_loop_mib_entry dsa_loop_mibs[] = {
44 	[DSA_LOOP_PHY_READ_OK]	= { "phy_read_ok", },
45 	[DSA_LOOP_PHY_READ_ERR]	= { "phy_read_err", },
46 	[DSA_LOOP_PHY_WRITE_OK] = { "phy_write_ok", },
47 	[DSA_LOOP_PHY_WRITE_ERR] = { "phy_write_err", },
48 };
49 
50 struct dsa_loop_port {
51 	struct dsa_loop_mib_entry mib[__DSA_LOOP_CNT_MAX];
52 };
53 
54 #define DSA_LOOP_VLANS	5
55 
56 struct dsa_loop_priv {
57 	struct mii_bus	*bus;
58 	unsigned int	port_base;
59 	struct dsa_loop_vlan vlans[DSA_LOOP_VLANS];
60 	struct net_device *netdev;
61 	struct dsa_loop_port ports[DSA_MAX_PORTS];
62 	u16 pvid;
63 };
64 
65 static struct phy_device *phydevs[PHY_MAX_ADDR];
66 
67 static enum dsa_tag_protocol dsa_loop_get_protocol(struct dsa_switch *ds)
68 {
69 	dev_dbg(ds->dev, "%s\n", __func__);
70 
71 	return DSA_TAG_PROTO_NONE;
72 }
73 
74 static int dsa_loop_setup(struct dsa_switch *ds)
75 {
76 	struct dsa_loop_priv *ps = ds->priv;
77 	unsigned int i;
78 
79 	for (i = 0; i < ds->num_ports; i++)
80 		memcpy(ps->ports[i].mib, dsa_loop_mibs,
81 		       sizeof(dsa_loop_mibs));
82 
83 	dev_dbg(ds->dev, "%s\n", __func__);
84 
85 	return 0;
86 }
87 
88 static int dsa_loop_get_sset_count(struct dsa_switch *ds)
89 {
90 	return __DSA_LOOP_CNT_MAX;
91 }
92 
93 static void dsa_loop_get_strings(struct dsa_switch *ds, int port, uint8_t *data)
94 {
95 	struct dsa_loop_priv *ps = ds->priv;
96 	unsigned int i;
97 
98 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
99 		memcpy(data + i * ETH_GSTRING_LEN,
100 		       ps->ports[port].mib[i].name, ETH_GSTRING_LEN);
101 }
102 
103 static void dsa_loop_get_ethtool_stats(struct dsa_switch *ds, int port,
104 				       uint64_t *data)
105 {
106 	struct dsa_loop_priv *ps = ds->priv;
107 	unsigned int i;
108 
109 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
110 		data[i] = ps->ports[port].mib[i].val;
111 }
112 
113 static int dsa_loop_phy_read(struct dsa_switch *ds, int port, int regnum)
114 {
115 	struct dsa_loop_priv *ps = ds->priv;
116 	struct mii_bus *bus = ps->bus;
117 	int ret;
118 
119 	dev_dbg(ds->dev, "%s\n", __func__);
120 
121 	ret = mdiobus_read_nested(bus, ps->port_base + port, regnum);
122 	if (ret < 0)
123 		ps->ports[port].mib[DSA_LOOP_PHY_READ_ERR].val++;
124 	else
125 		ps->ports[port].mib[DSA_LOOP_PHY_READ_OK].val++;
126 
127 	return ret;
128 }
129 
130 static int dsa_loop_phy_write(struct dsa_switch *ds, int port,
131 			      int regnum, u16 value)
132 {
133 	struct dsa_loop_priv *ps = ds->priv;
134 	struct mii_bus *bus = ps->bus;
135 	int ret;
136 
137 	dev_dbg(ds->dev, "%s\n", __func__);
138 
139 	ret = mdiobus_write_nested(bus, ps->port_base + port, regnum, value);
140 	if (ret < 0)
141 		ps->ports[port].mib[DSA_LOOP_PHY_WRITE_ERR].val++;
142 	else
143 		ps->ports[port].mib[DSA_LOOP_PHY_WRITE_OK].val++;
144 
145 	return ret;
146 }
147 
148 static int dsa_loop_port_bridge_join(struct dsa_switch *ds, int port,
149 				     struct net_device *bridge)
150 {
151 	dev_dbg(ds->dev, "%s\n", __func__);
152 
153 	return 0;
154 }
155 
156 static void dsa_loop_port_bridge_leave(struct dsa_switch *ds, int port,
157 				       struct net_device *bridge)
158 {
159 	dev_dbg(ds->dev, "%s\n", __func__);
160 }
161 
162 static void dsa_loop_port_stp_state_set(struct dsa_switch *ds, int port,
163 					u8 state)
164 {
165 	dev_dbg(ds->dev, "%s\n", __func__);
166 }
167 
168 static int dsa_loop_port_vlan_filtering(struct dsa_switch *ds, int port,
169 					bool vlan_filtering)
170 {
171 	dev_dbg(ds->dev, "%s\n", __func__);
172 
173 	return 0;
174 }
175 
176 static int dsa_loop_port_vlan_prepare(struct dsa_switch *ds, int port,
177 				      const struct switchdev_obj_port_vlan *vlan,
178 				      struct switchdev_trans *trans)
179 {
180 	struct dsa_loop_priv *ps = ds->priv;
181 	struct mii_bus *bus = ps->bus;
182 
183 	dev_dbg(ds->dev, "%s\n", __func__);
184 
185 	/* Just do a sleeping operation to make lockdep checks effective */
186 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
187 
188 	if (vlan->vid_end > DSA_LOOP_VLANS)
189 		return -ERANGE;
190 
191 	return 0;
192 }
193 
194 static void dsa_loop_port_vlan_add(struct dsa_switch *ds, int port,
195 				   const struct switchdev_obj_port_vlan *vlan,
196 				   struct switchdev_trans *trans)
197 {
198 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
199 	bool pvid = vlan->flags & BRIDGE_VLAN_INFO_PVID;
200 	struct dsa_loop_priv *ps = ds->priv;
201 	struct mii_bus *bus = ps->bus;
202 	struct dsa_loop_vlan *vl;
203 	u16 vid;
204 
205 	dev_dbg(ds->dev, "%s\n", __func__);
206 
207 	/* Just do a sleeping operation to make lockdep checks effective */
208 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
209 
210 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
211 		vl = &ps->vlans[vid];
212 
213 		vl->members |= BIT(port);
214 		if (untagged)
215 			vl->untagged |= BIT(port);
216 		else
217 			vl->untagged &= ~BIT(port);
218 	}
219 
220 	if (pvid)
221 		ps->pvid = vid;
222 }
223 
224 static int dsa_loop_port_vlan_del(struct dsa_switch *ds, int port,
225 				  const struct switchdev_obj_port_vlan *vlan)
226 {
227 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
228 	struct dsa_loop_priv *ps = ds->priv;
229 	struct mii_bus *bus = ps->bus;
230 	struct dsa_loop_vlan *vl;
231 	u16 vid, pvid = ps->pvid;
232 
233 	dev_dbg(ds->dev, "%s\n", __func__);
234 
235 	/* Just do a sleeping operation to make lockdep checks effective */
236 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
237 
238 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
239 		vl = &ps->vlans[vid];
240 
241 		vl->members &= ~BIT(port);
242 		if (untagged)
243 			vl->untagged &= ~BIT(port);
244 
245 		if (pvid == vid)
246 			pvid = 1;
247 	}
248 	ps->pvid = pvid;
249 
250 	return 0;
251 }
252 
253 static const struct dsa_switch_ops dsa_loop_driver = {
254 	.get_tag_protocol	= dsa_loop_get_protocol,
255 	.setup			= dsa_loop_setup,
256 	.get_strings		= dsa_loop_get_strings,
257 	.get_ethtool_stats	= dsa_loop_get_ethtool_stats,
258 	.get_sset_count		= dsa_loop_get_sset_count,
259 	.phy_read		= dsa_loop_phy_read,
260 	.phy_write		= dsa_loop_phy_write,
261 	.port_bridge_join	= dsa_loop_port_bridge_join,
262 	.port_bridge_leave	= dsa_loop_port_bridge_leave,
263 	.port_stp_state_set	= dsa_loop_port_stp_state_set,
264 	.port_vlan_filtering	= dsa_loop_port_vlan_filtering,
265 	.port_vlan_prepare	= dsa_loop_port_vlan_prepare,
266 	.port_vlan_add		= dsa_loop_port_vlan_add,
267 	.port_vlan_del		= dsa_loop_port_vlan_del,
268 };
269 
270 static int dsa_loop_drv_probe(struct mdio_device *mdiodev)
271 {
272 	struct dsa_loop_pdata *pdata = mdiodev->dev.platform_data;
273 	struct dsa_loop_priv *ps;
274 	struct dsa_switch *ds;
275 
276 	if (!pdata)
277 		return -ENODEV;
278 
279 	dev_info(&mdiodev->dev, "%s: 0x%0x\n",
280 		 pdata->name, pdata->enabled_ports);
281 
282 	ds = dsa_switch_alloc(&mdiodev->dev, DSA_MAX_PORTS);
283 	if (!ds)
284 		return -ENOMEM;
285 
286 	ps = devm_kzalloc(&mdiodev->dev, sizeof(*ps), GFP_KERNEL);
287 	if (!ps)
288 		return -ENOMEM;
289 
290 	ps->netdev = dev_get_by_name(&init_net, pdata->netdev);
291 	if (!ps->netdev)
292 		return -EPROBE_DEFER;
293 
294 	pdata->cd.netdev[DSA_LOOP_CPU_PORT] = &ps->netdev->dev;
295 
296 	ds->dev = &mdiodev->dev;
297 	ds->ops = &dsa_loop_driver;
298 	ds->priv = ps;
299 	ps->bus = mdiodev->bus;
300 
301 	dev_set_drvdata(&mdiodev->dev, ds);
302 
303 	return dsa_register_switch(ds);
304 }
305 
306 static void dsa_loop_drv_remove(struct mdio_device *mdiodev)
307 {
308 	struct dsa_switch *ds = dev_get_drvdata(&mdiodev->dev);
309 	struct dsa_loop_priv *ps = ds->priv;
310 
311 	dsa_unregister_switch(ds);
312 	dev_put(ps->netdev);
313 }
314 
315 static struct mdio_driver dsa_loop_drv = {
316 	.mdiodrv.driver	= {
317 		.name	= "dsa-loop",
318 	},
319 	.probe	= dsa_loop_drv_probe,
320 	.remove	= dsa_loop_drv_remove,
321 };
322 
323 #define NUM_FIXED_PHYS	(DSA_LOOP_NUM_PORTS - 2)
324 
325 static int __init dsa_loop_init(void)
326 {
327 	struct fixed_phy_status status = {
328 		.link = 1,
329 		.speed = SPEED_100,
330 		.duplex = DUPLEX_FULL,
331 	};
332 	unsigned int i;
333 
334 	for (i = 0; i < NUM_FIXED_PHYS; i++)
335 		phydevs[i] = fixed_phy_register(PHY_POLL, &status, -1, NULL);
336 
337 	return mdio_driver_register(&dsa_loop_drv);
338 }
339 module_init(dsa_loop_init);
340 
341 static void __exit dsa_loop_exit(void)
342 {
343 	unsigned int i;
344 
345 	mdio_driver_unregister(&dsa_loop_drv);
346 	for (i = 0; i < NUM_FIXED_PHYS; i++)
347 		if (!IS_ERR(phydevs[i]))
348 			fixed_phy_unregister(phydevs[i]);
349 }
350 module_exit(dsa_loop_exit);
351 
352 MODULE_LICENSE("GPL");
353 MODULE_AUTHOR("Florian Fainelli");
354 MODULE_DESCRIPTION("DSA loopback driver");
355