xref: /openbmc/linux/drivers/net/dsa/dsa_loop.c (revision 4a3fad70)
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 						   int port)
69 {
70 	dev_dbg(ds->dev, "%s\n", __func__);
71 
72 	return DSA_TAG_PROTO_NONE;
73 }
74 
75 static int dsa_loop_setup(struct dsa_switch *ds)
76 {
77 	struct dsa_loop_priv *ps = ds->priv;
78 	unsigned int i;
79 
80 	for (i = 0; i < ds->num_ports; i++)
81 		memcpy(ps->ports[i].mib, dsa_loop_mibs,
82 		       sizeof(dsa_loop_mibs));
83 
84 	dev_dbg(ds->dev, "%s\n", __func__);
85 
86 	return 0;
87 }
88 
89 static int dsa_loop_get_sset_count(struct dsa_switch *ds)
90 {
91 	return __DSA_LOOP_CNT_MAX;
92 }
93 
94 static void dsa_loop_get_strings(struct dsa_switch *ds, int port, uint8_t *data)
95 {
96 	struct dsa_loop_priv *ps = ds->priv;
97 	unsigned int i;
98 
99 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
100 		memcpy(data + i * ETH_GSTRING_LEN,
101 		       ps->ports[port].mib[i].name, ETH_GSTRING_LEN);
102 }
103 
104 static void dsa_loop_get_ethtool_stats(struct dsa_switch *ds, int port,
105 				       uint64_t *data)
106 {
107 	struct dsa_loop_priv *ps = ds->priv;
108 	unsigned int i;
109 
110 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
111 		data[i] = ps->ports[port].mib[i].val;
112 }
113 
114 static int dsa_loop_phy_read(struct dsa_switch *ds, int port, int regnum)
115 {
116 	struct dsa_loop_priv *ps = ds->priv;
117 	struct mii_bus *bus = ps->bus;
118 	int ret;
119 
120 	dev_dbg(ds->dev, "%s\n", __func__);
121 
122 	ret = mdiobus_read_nested(bus, ps->port_base + port, regnum);
123 	if (ret < 0)
124 		ps->ports[port].mib[DSA_LOOP_PHY_READ_ERR].val++;
125 	else
126 		ps->ports[port].mib[DSA_LOOP_PHY_READ_OK].val++;
127 
128 	return ret;
129 }
130 
131 static int dsa_loop_phy_write(struct dsa_switch *ds, int port,
132 			      int regnum, u16 value)
133 {
134 	struct dsa_loop_priv *ps = ds->priv;
135 	struct mii_bus *bus = ps->bus;
136 	int ret;
137 
138 	dev_dbg(ds->dev, "%s\n", __func__);
139 
140 	ret = mdiobus_write_nested(bus, ps->port_base + port, regnum, value);
141 	if (ret < 0)
142 		ps->ports[port].mib[DSA_LOOP_PHY_WRITE_ERR].val++;
143 	else
144 		ps->ports[port].mib[DSA_LOOP_PHY_WRITE_OK].val++;
145 
146 	return ret;
147 }
148 
149 static int dsa_loop_port_bridge_join(struct dsa_switch *ds, int port,
150 				     struct net_device *bridge)
151 {
152 	dev_dbg(ds->dev, "%s\n", __func__);
153 
154 	return 0;
155 }
156 
157 static void dsa_loop_port_bridge_leave(struct dsa_switch *ds, int port,
158 				       struct net_device *bridge)
159 {
160 	dev_dbg(ds->dev, "%s\n", __func__);
161 }
162 
163 static void dsa_loop_port_stp_state_set(struct dsa_switch *ds, int port,
164 					u8 state)
165 {
166 	dev_dbg(ds->dev, "%s\n", __func__);
167 }
168 
169 static int dsa_loop_port_vlan_filtering(struct dsa_switch *ds, int port,
170 					bool vlan_filtering)
171 {
172 	dev_dbg(ds->dev, "%s\n", __func__);
173 
174 	return 0;
175 }
176 
177 static int dsa_loop_port_vlan_prepare(struct dsa_switch *ds, int port,
178 				      const struct switchdev_obj_port_vlan *vlan,
179 				      struct switchdev_trans *trans)
180 {
181 	struct dsa_loop_priv *ps = ds->priv;
182 	struct mii_bus *bus = ps->bus;
183 
184 	dev_dbg(ds->dev, "%s\n", __func__);
185 
186 	/* Just do a sleeping operation to make lockdep checks effective */
187 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
188 
189 	if (vlan->vid_end > DSA_LOOP_VLANS)
190 		return -ERANGE;
191 
192 	return 0;
193 }
194 
195 static void dsa_loop_port_vlan_add(struct dsa_switch *ds, int port,
196 				   const struct switchdev_obj_port_vlan *vlan,
197 				   struct switchdev_trans *trans)
198 {
199 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
200 	bool pvid = vlan->flags & BRIDGE_VLAN_INFO_PVID;
201 	struct dsa_loop_priv *ps = ds->priv;
202 	struct mii_bus *bus = ps->bus;
203 	struct dsa_loop_vlan *vl;
204 	u16 vid;
205 
206 	dev_dbg(ds->dev, "%s\n", __func__);
207 
208 	/* Just do a sleeping operation to make lockdep checks effective */
209 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
210 
211 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
212 		vl = &ps->vlans[vid];
213 
214 		vl->members |= BIT(port);
215 		if (untagged)
216 			vl->untagged |= BIT(port);
217 		else
218 			vl->untagged &= ~BIT(port);
219 	}
220 
221 	if (pvid)
222 		ps->pvid = vid;
223 }
224 
225 static int dsa_loop_port_vlan_del(struct dsa_switch *ds, int port,
226 				  const struct switchdev_obj_port_vlan *vlan)
227 {
228 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
229 	struct dsa_loop_priv *ps = ds->priv;
230 	struct mii_bus *bus = ps->bus;
231 	struct dsa_loop_vlan *vl;
232 	u16 vid, pvid = ps->pvid;
233 
234 	dev_dbg(ds->dev, "%s\n", __func__);
235 
236 	/* Just do a sleeping operation to make lockdep checks effective */
237 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
238 
239 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
240 		vl = &ps->vlans[vid];
241 
242 		vl->members &= ~BIT(port);
243 		if (untagged)
244 			vl->untagged &= ~BIT(port);
245 
246 		if (pvid == vid)
247 			pvid = 1;
248 	}
249 	ps->pvid = pvid;
250 
251 	return 0;
252 }
253 
254 static const struct dsa_switch_ops dsa_loop_driver = {
255 	.get_tag_protocol	= dsa_loop_get_protocol,
256 	.setup			= dsa_loop_setup,
257 	.get_strings		= dsa_loop_get_strings,
258 	.get_ethtool_stats	= dsa_loop_get_ethtool_stats,
259 	.get_sset_count		= dsa_loop_get_sset_count,
260 	.phy_read		= dsa_loop_phy_read,
261 	.phy_write		= dsa_loop_phy_write,
262 	.port_bridge_join	= dsa_loop_port_bridge_join,
263 	.port_bridge_leave	= dsa_loop_port_bridge_leave,
264 	.port_stp_state_set	= dsa_loop_port_stp_state_set,
265 	.port_vlan_filtering	= dsa_loop_port_vlan_filtering,
266 	.port_vlan_prepare	= dsa_loop_port_vlan_prepare,
267 	.port_vlan_add		= dsa_loop_port_vlan_add,
268 	.port_vlan_del		= dsa_loop_port_vlan_del,
269 };
270 
271 static int dsa_loop_drv_probe(struct mdio_device *mdiodev)
272 {
273 	struct dsa_loop_pdata *pdata = mdiodev->dev.platform_data;
274 	struct dsa_loop_priv *ps;
275 	struct dsa_switch *ds;
276 
277 	if (!pdata)
278 		return -ENODEV;
279 
280 	dev_info(&mdiodev->dev, "%s: 0x%0x\n",
281 		 pdata->name, pdata->enabled_ports);
282 
283 	ds = dsa_switch_alloc(&mdiodev->dev, DSA_MAX_PORTS);
284 	if (!ds)
285 		return -ENOMEM;
286 
287 	ps = devm_kzalloc(&mdiodev->dev, sizeof(*ps), GFP_KERNEL);
288 	if (!ps)
289 		return -ENOMEM;
290 
291 	ps->netdev = dev_get_by_name(&init_net, pdata->netdev);
292 	if (!ps->netdev)
293 		return -EPROBE_DEFER;
294 
295 	pdata->cd.netdev[DSA_LOOP_CPU_PORT] = &ps->netdev->dev;
296 
297 	ds->dev = &mdiodev->dev;
298 	ds->ops = &dsa_loop_driver;
299 	ds->priv = ps;
300 	ps->bus = mdiodev->bus;
301 
302 	dev_set_drvdata(&mdiodev->dev, ds);
303 
304 	return dsa_register_switch(ds);
305 }
306 
307 static void dsa_loop_drv_remove(struct mdio_device *mdiodev)
308 {
309 	struct dsa_switch *ds = dev_get_drvdata(&mdiodev->dev);
310 	struct dsa_loop_priv *ps = ds->priv;
311 
312 	dsa_unregister_switch(ds);
313 	dev_put(ps->netdev);
314 }
315 
316 static struct mdio_driver dsa_loop_drv = {
317 	.mdiodrv.driver	= {
318 		.name	= "dsa-loop",
319 	},
320 	.probe	= dsa_loop_drv_probe,
321 	.remove	= dsa_loop_drv_remove,
322 };
323 
324 #define NUM_FIXED_PHYS	(DSA_LOOP_NUM_PORTS - 2)
325 
326 static int __init dsa_loop_init(void)
327 {
328 	struct fixed_phy_status status = {
329 		.link = 1,
330 		.speed = SPEED_100,
331 		.duplex = DUPLEX_FULL,
332 	};
333 	unsigned int i;
334 
335 	for (i = 0; i < NUM_FIXED_PHYS; i++)
336 		phydevs[i] = fixed_phy_register(PHY_POLL, &status, -1, NULL);
337 
338 	return mdio_driver_register(&dsa_loop_drv);
339 }
340 module_init(dsa_loop_init);
341 
342 static void __exit dsa_loop_exit(void)
343 {
344 	unsigned int i;
345 
346 	mdio_driver_unregister(&dsa_loop_drv);
347 	for (i = 0; i < NUM_FIXED_PHYS; i++)
348 		if (!IS_ERR(phydevs[i]))
349 			fixed_phy_unregister(phydevs[i]);
350 }
351 module_exit(dsa_loop_exit);
352 
353 MODULE_LICENSE("GPL");
354 MODULE_AUTHOR("Florian Fainelli");
355 MODULE_DESCRIPTION("DSA loopback driver");
356