xref: /openbmc/linux/drivers/net/dsa/dsa_loop.c (revision dc6a81c3)
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 						   enum dsa_tag_protocol mp)
66 {
67 	dev_dbg(ds->dev, "%s: port: %d\n", __func__, port);
68 
69 	return DSA_TAG_PROTO_NONE;
70 }
71 
72 static int dsa_loop_setup(struct dsa_switch *ds)
73 {
74 	struct dsa_loop_priv *ps = ds->priv;
75 	unsigned int i;
76 
77 	for (i = 0; i < ds->num_ports; i++)
78 		memcpy(ps->ports[i].mib, dsa_loop_mibs,
79 		       sizeof(dsa_loop_mibs));
80 
81 	dev_dbg(ds->dev, "%s\n", __func__);
82 
83 	return 0;
84 }
85 
86 static int dsa_loop_get_sset_count(struct dsa_switch *ds, int port, int sset)
87 {
88 	if (sset != ETH_SS_STATS && sset != ETH_SS_PHY_STATS)
89 		return 0;
90 
91 	return __DSA_LOOP_CNT_MAX;
92 }
93 
94 static void dsa_loop_get_strings(struct dsa_switch *ds, int port,
95 				 u32 stringset, uint8_t *data)
96 {
97 	struct dsa_loop_priv *ps = ds->priv;
98 	unsigned int i;
99 
100 	if (stringset != ETH_SS_STATS && stringset != ETH_SS_PHY_STATS)
101 		return;
102 
103 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
104 		memcpy(data + i * ETH_GSTRING_LEN,
105 		       ps->ports[port].mib[i].name, ETH_GSTRING_LEN);
106 }
107 
108 static void dsa_loop_get_ethtool_stats(struct dsa_switch *ds, int port,
109 				       uint64_t *data)
110 {
111 	struct dsa_loop_priv *ps = ds->priv;
112 	unsigned int i;
113 
114 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
115 		data[i] = ps->ports[port].mib[i].val;
116 }
117 
118 static int dsa_loop_phy_read(struct dsa_switch *ds, int port, int regnum)
119 {
120 	struct dsa_loop_priv *ps = ds->priv;
121 	struct mii_bus *bus = ps->bus;
122 	int ret;
123 
124 	ret = mdiobus_read_nested(bus, ps->port_base + port, regnum);
125 	if (ret < 0)
126 		ps->ports[port].mib[DSA_LOOP_PHY_READ_ERR].val++;
127 	else
128 		ps->ports[port].mib[DSA_LOOP_PHY_READ_OK].val++;
129 
130 	return ret;
131 }
132 
133 static int dsa_loop_phy_write(struct dsa_switch *ds, int port,
134 			      int regnum, u16 value)
135 {
136 	struct dsa_loop_priv *ps = ds->priv;
137 	struct mii_bus *bus = ps->bus;
138 	int ret;
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: port: %d, bridge: %s\n",
153 		__func__, port, bridge->name);
154 
155 	return 0;
156 }
157 
158 static void dsa_loop_port_bridge_leave(struct dsa_switch *ds, int port,
159 				       struct net_device *bridge)
160 {
161 	dev_dbg(ds->dev, "%s: port: %d, bridge: %s\n",
162 		__func__, port, bridge->name);
163 }
164 
165 static void dsa_loop_port_stp_state_set(struct dsa_switch *ds, int port,
166 					u8 state)
167 {
168 	dev_dbg(ds->dev, "%s: port: %d, state: %d\n",
169 		__func__, port, state);
170 }
171 
172 static int dsa_loop_port_vlan_filtering(struct dsa_switch *ds, int port,
173 					bool vlan_filtering)
174 {
175 	dev_dbg(ds->dev, "%s: port: %d, vlan_filtering: %d\n",
176 		__func__, port, vlan_filtering);
177 
178 	return 0;
179 }
180 
181 static int
182 dsa_loop_port_vlan_prepare(struct dsa_switch *ds, int port,
183 			   const struct switchdev_obj_port_vlan *vlan)
184 {
185 	struct dsa_loop_priv *ps = ds->priv;
186 	struct mii_bus *bus = ps->bus;
187 
188 	dev_dbg(ds->dev, "%s: port: %d, vlan: %d-%d",
189 		__func__, port, vlan->vid_begin, vlan->vid_end);
190 
191 	/* Just do a sleeping operation to make lockdep checks effective */
192 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
193 
194 	if (vlan->vid_end > DSA_LOOP_VLANS)
195 		return -ERANGE;
196 
197 	return 0;
198 }
199 
200 static void dsa_loop_port_vlan_add(struct dsa_switch *ds, int port,
201 				   const struct switchdev_obj_port_vlan *vlan)
202 {
203 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
204 	bool pvid = vlan->flags & BRIDGE_VLAN_INFO_PVID;
205 	struct dsa_loop_priv *ps = ds->priv;
206 	struct mii_bus *bus = ps->bus;
207 	struct dsa_loop_vlan *vl;
208 	u16 vid;
209 
210 	/* Just do a sleeping operation to make lockdep checks effective */
211 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
212 
213 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
214 		vl = &ps->vlans[vid];
215 
216 		vl->members |= BIT(port);
217 		if (untagged)
218 			vl->untagged |= BIT(port);
219 		else
220 			vl->untagged &= ~BIT(port);
221 
222 		dev_dbg(ds->dev, "%s: port: %d vlan: %d, %stagged, pvid: %d\n",
223 			__func__, port, vid, untagged ? "un" : "", pvid);
224 	}
225 
226 	if (pvid)
227 		ps->pvid = vid;
228 }
229 
230 static int dsa_loop_port_vlan_del(struct dsa_switch *ds, int port,
231 				  const struct switchdev_obj_port_vlan *vlan)
232 {
233 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
234 	struct dsa_loop_priv *ps = ds->priv;
235 	struct mii_bus *bus = ps->bus;
236 	struct dsa_loop_vlan *vl;
237 	u16 vid, pvid = ps->pvid;
238 
239 	/* Just do a sleeping operation to make lockdep checks effective */
240 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
241 
242 	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
243 		vl = &ps->vlans[vid];
244 
245 		vl->members &= ~BIT(port);
246 		if (untagged)
247 			vl->untagged &= ~BIT(port);
248 
249 		if (pvid == vid)
250 			pvid = 1;
251 
252 		dev_dbg(ds->dev, "%s: port: %d vlan: %d, %stagged, pvid: %d\n",
253 			__func__, port, vid, untagged ? "un" : "", pvid);
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 = devm_kzalloc(&mdiodev->dev, sizeof(*ds), GFP_KERNEL);
291 	if (!ds)
292 		return -ENOMEM;
293 
294 	ds->dev = &mdiodev->dev;
295 	ds->num_ports = DSA_MAX_PORTS;
296 
297 	ps = devm_kzalloc(&mdiodev->dev, sizeof(*ps), GFP_KERNEL);
298 	if (!ps)
299 		return -ENOMEM;
300 
301 	ps->netdev = dev_get_by_name(&init_net, pdata->netdev);
302 	if (!ps->netdev)
303 		return -EPROBE_DEFER;
304 
305 	pdata->cd.netdev[DSA_LOOP_CPU_PORT] = &ps->netdev->dev;
306 
307 	ds->dev = &mdiodev->dev;
308 	ds->ops = &dsa_loop_driver;
309 	ds->priv = ps;
310 	ps->bus = mdiodev->bus;
311 
312 	dev_set_drvdata(&mdiodev->dev, ds);
313 
314 	return dsa_register_switch(ds);
315 }
316 
317 static void dsa_loop_drv_remove(struct mdio_device *mdiodev)
318 {
319 	struct dsa_switch *ds = dev_get_drvdata(&mdiodev->dev);
320 	struct dsa_loop_priv *ps = ds->priv;
321 
322 	dsa_unregister_switch(ds);
323 	dev_put(ps->netdev);
324 }
325 
326 static struct mdio_driver dsa_loop_drv = {
327 	.mdiodrv.driver	= {
328 		.name	= "dsa-loop",
329 	},
330 	.probe	= dsa_loop_drv_probe,
331 	.remove	= dsa_loop_drv_remove,
332 };
333 
334 #define NUM_FIXED_PHYS	(DSA_LOOP_NUM_PORTS - 2)
335 
336 static int __init dsa_loop_init(void)
337 {
338 	struct fixed_phy_status status = {
339 		.link = 1,
340 		.speed = SPEED_100,
341 		.duplex = DUPLEX_FULL,
342 	};
343 	unsigned int i;
344 
345 	for (i = 0; i < NUM_FIXED_PHYS; i++)
346 		phydevs[i] = fixed_phy_register(PHY_POLL, &status, NULL);
347 
348 	return mdio_driver_register(&dsa_loop_drv);
349 }
350 module_init(dsa_loop_init);
351 
352 static void __exit dsa_loop_exit(void)
353 {
354 	unsigned int i;
355 
356 	mdio_driver_unregister(&dsa_loop_drv);
357 	for (i = 0; i < NUM_FIXED_PHYS; i++)
358 		if (!IS_ERR(phydevs[i]))
359 			fixed_phy_unregister(phydevs[i]);
360 }
361 module_exit(dsa_loop_exit);
362 
363 MODULE_LICENSE("GPL");
364 MODULE_AUTHOR("Florian Fainelli");
365 MODULE_DESCRIPTION("DSA loopback driver");
366