xref: /openbmc/linux/drivers/net/dsa/dsa_loop.c (revision d2ba09c1)
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, int port, int sset)
90 {
91 	if (sset != ETH_SS_STATS && sset != ETH_SS_PHY_STATS)
92 		return 0;
93 
94 	return __DSA_LOOP_CNT_MAX;
95 }
96 
97 static void dsa_loop_get_strings(struct dsa_switch *ds, int port,
98 				 u32 stringset, uint8_t *data)
99 {
100 	struct dsa_loop_priv *ps = ds->priv;
101 	unsigned int i;
102 
103 	if (stringset != ETH_SS_STATS && stringset != ETH_SS_PHY_STATS)
104 		return;
105 
106 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
107 		memcpy(data + i * ETH_GSTRING_LEN,
108 		       ps->ports[port].mib[i].name, ETH_GSTRING_LEN);
109 }
110 
111 static void dsa_loop_get_ethtool_stats(struct dsa_switch *ds, int port,
112 				       uint64_t *data)
113 {
114 	struct dsa_loop_priv *ps = ds->priv;
115 	unsigned int i;
116 
117 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
118 		data[i] = ps->ports[port].mib[i].val;
119 }
120 
121 static int dsa_loop_phy_read(struct dsa_switch *ds, int port, int regnum)
122 {
123 	struct dsa_loop_priv *ps = ds->priv;
124 	struct mii_bus *bus = ps->bus;
125 	int ret;
126 
127 	dev_dbg(ds->dev, "%s\n", __func__);
128 
129 	ret = mdiobus_read_nested(bus, ps->port_base + port, regnum);
130 	if (ret < 0)
131 		ps->ports[port].mib[DSA_LOOP_PHY_READ_ERR].val++;
132 	else
133 		ps->ports[port].mib[DSA_LOOP_PHY_READ_OK].val++;
134 
135 	return ret;
136 }
137 
138 static int dsa_loop_phy_write(struct dsa_switch *ds, int port,
139 			      int regnum, u16 value)
140 {
141 	struct dsa_loop_priv *ps = ds->priv;
142 	struct mii_bus *bus = ps->bus;
143 	int ret;
144 
145 	dev_dbg(ds->dev, "%s\n", __func__);
146 
147 	ret = mdiobus_write_nested(bus, ps->port_base + port, regnum, value);
148 	if (ret < 0)
149 		ps->ports[port].mib[DSA_LOOP_PHY_WRITE_ERR].val++;
150 	else
151 		ps->ports[port].mib[DSA_LOOP_PHY_WRITE_OK].val++;
152 
153 	return ret;
154 }
155 
156 static int dsa_loop_port_bridge_join(struct dsa_switch *ds, int port,
157 				     struct net_device *bridge)
158 {
159 	dev_dbg(ds->dev, "%s\n", __func__);
160 
161 	return 0;
162 }
163 
164 static void dsa_loop_port_bridge_leave(struct dsa_switch *ds, int port,
165 				       struct net_device *bridge)
166 {
167 	dev_dbg(ds->dev, "%s\n", __func__);
168 }
169 
170 static void dsa_loop_port_stp_state_set(struct dsa_switch *ds, int port,
171 					u8 state)
172 {
173 	dev_dbg(ds->dev, "%s\n", __func__);
174 }
175 
176 static int dsa_loop_port_vlan_filtering(struct dsa_switch *ds, int port,
177 					bool vlan_filtering)
178 {
179 	dev_dbg(ds->dev, "%s\n", __func__);
180 
181 	return 0;
182 }
183 
184 static int
185 dsa_loop_port_vlan_prepare(struct dsa_switch *ds, int port,
186 			   const struct switchdev_obj_port_vlan *vlan)
187 {
188 	struct dsa_loop_priv *ps = ds->priv;
189 	struct mii_bus *bus = ps->bus;
190 
191 	dev_dbg(ds->dev, "%s\n", __func__);
192 
193 	/* Just do a sleeping operation to make lockdep checks effective */
194 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
195 
196 	if (vlan->vid_end > DSA_LOOP_VLANS)
197 		return -ERANGE;
198 
199 	return 0;
200 }
201 
202 static void dsa_loop_port_vlan_add(struct dsa_switch *ds, int port,
203 				   const struct switchdev_obj_port_vlan *vlan)
204 {
205 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
206 	bool pvid = vlan->flags & BRIDGE_VLAN_INFO_PVID;
207 	struct dsa_loop_priv *ps = ds->priv;
208 	struct mii_bus *bus = ps->bus;
209 	struct dsa_loop_vlan *vl;
210 	u16 vid;
211 
212 	dev_dbg(ds->dev, "%s\n", __func__);
213 
214 	/* Just do a sleeping operation to make lockdep checks effective */
215 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
216 
217 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
218 		vl = &ps->vlans[vid];
219 
220 		vl->members |= BIT(port);
221 		if (untagged)
222 			vl->untagged |= BIT(port);
223 		else
224 			vl->untagged &= ~BIT(port);
225 	}
226 
227 	if (pvid)
228 		ps->pvid = vid;
229 }
230 
231 static int dsa_loop_port_vlan_del(struct dsa_switch *ds, int port,
232 				  const struct switchdev_obj_port_vlan *vlan)
233 {
234 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
235 	struct dsa_loop_priv *ps = ds->priv;
236 	struct mii_bus *bus = ps->bus;
237 	struct dsa_loop_vlan *vl;
238 	u16 vid, pvid = ps->pvid;
239 
240 	dev_dbg(ds->dev, "%s\n", __func__);
241 
242 	/* Just do a sleeping operation to make lockdep checks effective */
243 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
244 
245 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
246 		vl = &ps->vlans[vid];
247 
248 		vl->members &= ~BIT(port);
249 		if (untagged)
250 			vl->untagged &= ~BIT(port);
251 
252 		if (pvid == vid)
253 			pvid = 1;
254 	}
255 	ps->pvid = pvid;
256 
257 	return 0;
258 }
259 
260 static const struct dsa_switch_ops dsa_loop_driver = {
261 	.get_tag_protocol	= dsa_loop_get_protocol,
262 	.setup			= dsa_loop_setup,
263 	.get_strings		= dsa_loop_get_strings,
264 	.get_ethtool_stats	= dsa_loop_get_ethtool_stats,
265 	.get_sset_count		= dsa_loop_get_sset_count,
266 	.get_ethtool_phy_stats	= dsa_loop_get_ethtool_stats,
267 	.phy_read		= dsa_loop_phy_read,
268 	.phy_write		= dsa_loop_phy_write,
269 	.port_bridge_join	= dsa_loop_port_bridge_join,
270 	.port_bridge_leave	= dsa_loop_port_bridge_leave,
271 	.port_stp_state_set	= dsa_loop_port_stp_state_set,
272 	.port_vlan_filtering	= dsa_loop_port_vlan_filtering,
273 	.port_vlan_prepare	= dsa_loop_port_vlan_prepare,
274 	.port_vlan_add		= dsa_loop_port_vlan_add,
275 	.port_vlan_del		= dsa_loop_port_vlan_del,
276 };
277 
278 static int dsa_loop_drv_probe(struct mdio_device *mdiodev)
279 {
280 	struct dsa_loop_pdata *pdata = mdiodev->dev.platform_data;
281 	struct dsa_loop_priv *ps;
282 	struct dsa_switch *ds;
283 
284 	if (!pdata)
285 		return -ENODEV;
286 
287 	dev_info(&mdiodev->dev, "%s: 0x%0x\n",
288 		 pdata->name, pdata->enabled_ports);
289 
290 	ds = dsa_switch_alloc(&mdiodev->dev, DSA_MAX_PORTS);
291 	if (!ds)
292 		return -ENOMEM;
293 
294 	ps = devm_kzalloc(&mdiodev->dev, sizeof(*ps), GFP_KERNEL);
295 	if (!ps)
296 		return -ENOMEM;
297 
298 	ps->netdev = dev_get_by_name(&init_net, pdata->netdev);
299 	if (!ps->netdev)
300 		return -EPROBE_DEFER;
301 
302 	pdata->cd.netdev[DSA_LOOP_CPU_PORT] = &ps->netdev->dev;
303 
304 	ds->dev = &mdiodev->dev;
305 	ds->ops = &dsa_loop_driver;
306 	ds->priv = ps;
307 	ps->bus = mdiodev->bus;
308 
309 	dev_set_drvdata(&mdiodev->dev, ds);
310 
311 	return dsa_register_switch(ds);
312 }
313 
314 static void dsa_loop_drv_remove(struct mdio_device *mdiodev)
315 {
316 	struct dsa_switch *ds = dev_get_drvdata(&mdiodev->dev);
317 	struct dsa_loop_priv *ps = ds->priv;
318 
319 	dsa_unregister_switch(ds);
320 	dev_put(ps->netdev);
321 }
322 
323 static struct mdio_driver dsa_loop_drv = {
324 	.mdiodrv.driver	= {
325 		.name	= "dsa-loop",
326 	},
327 	.probe	= dsa_loop_drv_probe,
328 	.remove	= dsa_loop_drv_remove,
329 };
330 
331 #define NUM_FIXED_PHYS	(DSA_LOOP_NUM_PORTS - 2)
332 
333 static int __init dsa_loop_init(void)
334 {
335 	struct fixed_phy_status status = {
336 		.link = 1,
337 		.speed = SPEED_100,
338 		.duplex = DUPLEX_FULL,
339 	};
340 	unsigned int i;
341 
342 	for (i = 0; i < NUM_FIXED_PHYS; i++)
343 		phydevs[i] = fixed_phy_register(PHY_POLL, &status, -1, NULL);
344 
345 	return mdio_driver_register(&dsa_loop_drv);
346 }
347 module_init(dsa_loop_init);
348 
349 static void __exit dsa_loop_exit(void)
350 {
351 	unsigned int i;
352 
353 	mdio_driver_unregister(&dsa_loop_drv);
354 	for (i = 0; i < NUM_FIXED_PHYS; i++)
355 		if (!IS_ERR(phydevs[i]))
356 			fixed_phy_unregister(phydevs[i]);
357 }
358 module_exit(dsa_loop_exit);
359 
360 MODULE_LICENSE("GPL");
361 MODULE_AUTHOR("Florian Fainelli");
362 MODULE_DESCRIPTION("DSA loopback driver");
363