xref: /openbmc/linux/drivers/net/dsa/dsa_loop.c (revision 9a6b55ac)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Distributed Switch Architecture loopback driver
4  *
5  * Copyright (C) 2016, Florian Fainelli <f.fainelli@gmail.com>
6  */
7 
8 #include <linux/platform_device.h>
9 #include <linux/netdevice.h>
10 #include <linux/phy.h>
11 #include <linux/phy_fixed.h>
12 #include <linux/export.h>
13 #include <linux/ethtool.h>
14 #include <linux/workqueue.h>
15 #include <linux/module.h>
16 #include <linux/if_bridge.h>
17 #include <net/dsa.h>
18 
19 #include "dsa_loop.h"
20 
21 struct dsa_loop_vlan {
22 	u16 members;
23 	u16 untagged;
24 };
25 
26 struct dsa_loop_mib_entry {
27 	char name[ETH_GSTRING_LEN];
28 	unsigned long val;
29 };
30 
31 enum dsa_loop_mib_counters {
32 	DSA_LOOP_PHY_READ_OK,
33 	DSA_LOOP_PHY_READ_ERR,
34 	DSA_LOOP_PHY_WRITE_OK,
35 	DSA_LOOP_PHY_WRITE_ERR,
36 	__DSA_LOOP_CNT_MAX,
37 };
38 
39 static struct dsa_loop_mib_entry dsa_loop_mibs[] = {
40 	[DSA_LOOP_PHY_READ_OK]	= { "phy_read_ok", },
41 	[DSA_LOOP_PHY_READ_ERR]	= { "phy_read_err", },
42 	[DSA_LOOP_PHY_WRITE_OK] = { "phy_write_ok", },
43 	[DSA_LOOP_PHY_WRITE_ERR] = { "phy_write_err", },
44 };
45 
46 struct dsa_loop_port {
47 	struct dsa_loop_mib_entry mib[__DSA_LOOP_CNT_MAX];
48 };
49 
50 #define DSA_LOOP_VLANS	5
51 
52 struct dsa_loop_priv {
53 	struct mii_bus	*bus;
54 	unsigned int	port_base;
55 	struct dsa_loop_vlan vlans[DSA_LOOP_VLANS];
56 	struct net_device *netdev;
57 	struct dsa_loop_port ports[DSA_MAX_PORTS];
58 	u16 pvid;
59 };
60 
61 static struct phy_device *phydevs[PHY_MAX_ADDR];
62 
63 static enum dsa_tag_protocol dsa_loop_get_protocol(struct dsa_switch *ds,
64 						   int port)
65 {
66 	dev_dbg(ds->dev, "%s: port: %d\n", __func__, port);
67 
68 	return DSA_TAG_PROTO_NONE;
69 }
70 
71 static int dsa_loop_setup(struct dsa_switch *ds)
72 {
73 	struct dsa_loop_priv *ps = ds->priv;
74 	unsigned int i;
75 
76 	for (i = 0; i < ds->num_ports; i++)
77 		memcpy(ps->ports[i].mib, dsa_loop_mibs,
78 		       sizeof(dsa_loop_mibs));
79 
80 	dev_dbg(ds->dev, "%s\n", __func__);
81 
82 	return 0;
83 }
84 
85 static int dsa_loop_get_sset_count(struct dsa_switch *ds, int port, int sset)
86 {
87 	if (sset != ETH_SS_STATS && sset != ETH_SS_PHY_STATS)
88 		return 0;
89 
90 	return __DSA_LOOP_CNT_MAX;
91 }
92 
93 static void dsa_loop_get_strings(struct dsa_switch *ds, int port,
94 				 u32 stringset, uint8_t *data)
95 {
96 	struct dsa_loop_priv *ps = ds->priv;
97 	unsigned int i;
98 
99 	if (stringset != ETH_SS_STATS && stringset != ETH_SS_PHY_STATS)
100 		return;
101 
102 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
103 		memcpy(data + i * ETH_GSTRING_LEN,
104 		       ps->ports[port].mib[i].name, ETH_GSTRING_LEN);
105 }
106 
107 static void dsa_loop_get_ethtool_stats(struct dsa_switch *ds, int port,
108 				       uint64_t *data)
109 {
110 	struct dsa_loop_priv *ps = ds->priv;
111 	unsigned int i;
112 
113 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
114 		data[i] = ps->ports[port].mib[i].val;
115 }
116 
117 static int dsa_loop_phy_read(struct dsa_switch *ds, int port, int regnum)
118 {
119 	struct dsa_loop_priv *ps = ds->priv;
120 	struct mii_bus *bus = ps->bus;
121 	int ret;
122 
123 	ret = mdiobus_read_nested(bus, ps->port_base + port, regnum);
124 	if (ret < 0)
125 		ps->ports[port].mib[DSA_LOOP_PHY_READ_ERR].val++;
126 	else
127 		ps->ports[port].mib[DSA_LOOP_PHY_READ_OK].val++;
128 
129 	return ret;
130 }
131 
132 static int dsa_loop_phy_write(struct dsa_switch *ds, int port,
133 			      int regnum, u16 value)
134 {
135 	struct dsa_loop_priv *ps = ds->priv;
136 	struct mii_bus *bus = ps->bus;
137 	int ret;
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: port: %d, bridge: %s\n",
152 		__func__, port, bridge->name);
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: port: %d, bridge: %s\n",
161 		__func__, port, bridge->name);
162 }
163 
164 static void dsa_loop_port_stp_state_set(struct dsa_switch *ds, int port,
165 					u8 state)
166 {
167 	dev_dbg(ds->dev, "%s: port: %d, state: %d\n",
168 		__func__, port, state);
169 }
170 
171 static int dsa_loop_port_vlan_filtering(struct dsa_switch *ds, int port,
172 					bool vlan_filtering)
173 {
174 	dev_dbg(ds->dev, "%s: port: %d, vlan_filtering: %d\n",
175 		__func__, port, vlan_filtering);
176 
177 	return 0;
178 }
179 
180 static int
181 dsa_loop_port_vlan_prepare(struct dsa_switch *ds, int port,
182 			   const struct switchdev_obj_port_vlan *vlan)
183 {
184 	struct dsa_loop_priv *ps = ds->priv;
185 	struct mii_bus *bus = ps->bus;
186 
187 	dev_dbg(ds->dev, "%s: port: %d, vlan: %d-%d",
188 		__func__, port, vlan->vid_begin, vlan->vid_end);
189 
190 	/* Just do a sleeping operation to make lockdep checks effective */
191 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
192 
193 	if (vlan->vid_end > DSA_LOOP_VLANS)
194 		return -ERANGE;
195 
196 	return 0;
197 }
198 
199 static void dsa_loop_port_vlan_add(struct dsa_switch *ds, int port,
200 				   const struct switchdev_obj_port_vlan *vlan)
201 {
202 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
203 	bool pvid = vlan->flags & BRIDGE_VLAN_INFO_PVID;
204 	struct dsa_loop_priv *ps = ds->priv;
205 	struct mii_bus *bus = ps->bus;
206 	struct dsa_loop_vlan *vl;
207 	u16 vid;
208 
209 	/* Just do a sleeping operation to make lockdep checks effective */
210 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
211 
212 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
213 		vl = &ps->vlans[vid];
214 
215 		vl->members |= BIT(port);
216 		if (untagged)
217 			vl->untagged |= BIT(port);
218 		else
219 			vl->untagged &= ~BIT(port);
220 
221 		dev_dbg(ds->dev, "%s: port: %d vlan: %d, %stagged, pvid: %d\n",
222 			__func__, port, vid, untagged ? "un" : "", pvid);
223 	}
224 
225 	if (pvid)
226 		ps->pvid = vid;
227 }
228 
229 static int dsa_loop_port_vlan_del(struct dsa_switch *ds, int port,
230 				  const struct switchdev_obj_port_vlan *vlan)
231 {
232 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
233 	struct dsa_loop_priv *ps = ds->priv;
234 	struct mii_bus *bus = ps->bus;
235 	struct dsa_loop_vlan *vl;
236 	u16 vid, pvid = ps->pvid;
237 
238 	/* Just do a sleeping operation to make lockdep checks effective */
239 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
240 
241 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
242 		vl = &ps->vlans[vid];
243 
244 		vl->members &= ~BIT(port);
245 		if (untagged)
246 			vl->untagged &= ~BIT(port);
247 
248 		if (pvid == vid)
249 			pvid = 1;
250 
251 		dev_dbg(ds->dev, "%s: port: %d vlan: %d, %stagged, pvid: %d\n",
252 			__func__, port, vid, untagged ? "un" : "", pvid);
253 	}
254 	ps->pvid = pvid;
255 
256 	return 0;
257 }
258 
259 static const struct dsa_switch_ops dsa_loop_driver = {
260 	.get_tag_protocol	= dsa_loop_get_protocol,
261 	.setup			= dsa_loop_setup,
262 	.get_strings		= dsa_loop_get_strings,
263 	.get_ethtool_stats	= dsa_loop_get_ethtool_stats,
264 	.get_sset_count		= dsa_loop_get_sset_count,
265 	.get_ethtool_phy_stats	= dsa_loop_get_ethtool_stats,
266 	.phy_read		= dsa_loop_phy_read,
267 	.phy_write		= dsa_loop_phy_write,
268 	.port_bridge_join	= dsa_loop_port_bridge_join,
269 	.port_bridge_leave	= dsa_loop_port_bridge_leave,
270 	.port_stp_state_set	= dsa_loop_port_stp_state_set,
271 	.port_vlan_filtering	= dsa_loop_port_vlan_filtering,
272 	.port_vlan_prepare	= dsa_loop_port_vlan_prepare,
273 	.port_vlan_add		= dsa_loop_port_vlan_add,
274 	.port_vlan_del		= dsa_loop_port_vlan_del,
275 };
276 
277 static int dsa_loop_drv_probe(struct mdio_device *mdiodev)
278 {
279 	struct dsa_loop_pdata *pdata = mdiodev->dev.platform_data;
280 	struct dsa_loop_priv *ps;
281 	struct dsa_switch *ds;
282 
283 	if (!pdata)
284 		return -ENODEV;
285 
286 	dev_info(&mdiodev->dev, "%s: 0x%0x\n",
287 		 pdata->name, pdata->enabled_ports);
288 
289 	ds = devm_kzalloc(&mdiodev->dev, sizeof(*ds), GFP_KERNEL);
290 	if (!ds)
291 		return -ENOMEM;
292 
293 	ds->dev = &mdiodev->dev;
294 	ds->num_ports = DSA_MAX_PORTS;
295 
296 	ps = devm_kzalloc(&mdiodev->dev, sizeof(*ps), GFP_KERNEL);
297 	if (!ps)
298 		return -ENOMEM;
299 
300 	ps->netdev = dev_get_by_name(&init_net, pdata->netdev);
301 	if (!ps->netdev)
302 		return -EPROBE_DEFER;
303 
304 	pdata->cd.netdev[DSA_LOOP_CPU_PORT] = &ps->netdev->dev;
305 
306 	ds->dev = &mdiodev->dev;
307 	ds->ops = &dsa_loop_driver;
308 	ds->priv = ps;
309 	ps->bus = mdiodev->bus;
310 
311 	dev_set_drvdata(&mdiodev->dev, ds);
312 
313 	return dsa_register_switch(ds);
314 }
315 
316 static void dsa_loop_drv_remove(struct mdio_device *mdiodev)
317 {
318 	struct dsa_switch *ds = dev_get_drvdata(&mdiodev->dev);
319 	struct dsa_loop_priv *ps = ds->priv;
320 
321 	dsa_unregister_switch(ds);
322 	dev_put(ps->netdev);
323 }
324 
325 static struct mdio_driver dsa_loop_drv = {
326 	.mdiodrv.driver	= {
327 		.name	= "dsa-loop",
328 	},
329 	.probe	= dsa_loop_drv_probe,
330 	.remove	= dsa_loop_drv_remove,
331 };
332 
333 #define NUM_FIXED_PHYS	(DSA_LOOP_NUM_PORTS - 2)
334 
335 static int __init dsa_loop_init(void)
336 {
337 	struct fixed_phy_status status = {
338 		.link = 1,
339 		.speed = SPEED_100,
340 		.duplex = DUPLEX_FULL,
341 	};
342 	unsigned int i;
343 
344 	for (i = 0; i < NUM_FIXED_PHYS; i++)
345 		phydevs[i] = fixed_phy_register(PHY_POLL, &status, NULL);
346 
347 	return mdio_driver_register(&dsa_loop_drv);
348 }
349 module_init(dsa_loop_init);
350 
351 static void __exit dsa_loop_exit(void)
352 {
353 	unsigned int i;
354 
355 	mdio_driver_unregister(&dsa_loop_drv);
356 	for (i = 0; i < NUM_FIXED_PHYS; i++)
357 		if (!IS_ERR(phydevs[i]))
358 			fixed_phy_unregister(phydevs[i]);
359 }
360 module_exit(dsa_loop_exit);
361 
362 MODULE_LICENSE("GPL");
363 MODULE_AUTHOR("Florian Fainelli");
364 MODULE_DESCRIPTION("DSA loopback driver");
365