xref: /linux/drivers/net/dsa/dsa_loop.c (revision ccde82e909467abdf098a8ee6f63e1ecf9a47ce5)
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 <linux/dsa/loop.h>
18 #include <net/dsa.h>
19 
20 #define DSA_LOOP_NUM_PORTS	6
21 #define DSA_LOOP_CPU_PORT	(DSA_LOOP_NUM_PORTS - 1)
22 #define NUM_FIXED_PHYS		(DSA_LOOP_NUM_PORTS - 2)
23 
24 struct dsa_loop_pdata {
25 	/* Must be first, such that dsa_register_switch() can access this
26 	 * without gory pointer manipulations
27 	 */
28 	struct dsa_chip_data cd;
29 	const char *name;
30 	unsigned int enabled_ports;
31 	const char *netdev;
32 };
33 
34 static struct dsa_loop_mib_entry dsa_loop_mibs[] = {
35 	[DSA_LOOP_PHY_READ_OK]	= { "phy_read_ok", },
36 	[DSA_LOOP_PHY_READ_ERR]	= { "phy_read_err", },
37 	[DSA_LOOP_PHY_WRITE_OK] = { "phy_write_ok", },
38 	[DSA_LOOP_PHY_WRITE_ERR] = { "phy_write_err", },
39 };
40 
41 static struct phy_device *phydevs[PHY_MAX_ADDR];
42 static struct mdio_device *switch_mdiodev;
43 
44 enum dsa_loop_devlink_resource_id {
45 	DSA_LOOP_DEVLINK_PARAM_ID_VTU,
46 };
47 
48 static u64 dsa_loop_devlink_vtu_get(void *priv)
49 {
50 	struct dsa_loop_priv *ps = priv;
51 	unsigned int i, count = 0;
52 	struct dsa_loop_vlan *vl;
53 
54 	for (i = 0; i < ARRAY_SIZE(ps->vlans); i++) {
55 		vl = &ps->vlans[i];
56 		if (vl->members)
57 			count++;
58 	}
59 
60 	return count;
61 }
62 
63 static int dsa_loop_setup_devlink_resources(struct dsa_switch *ds)
64 {
65 	struct devlink_resource_size_params size_params;
66 	struct dsa_loop_priv *ps = ds->priv;
67 	int err;
68 
69 	devlink_resource_size_params_init(&size_params, ARRAY_SIZE(ps->vlans),
70 					  ARRAY_SIZE(ps->vlans),
71 					  1, DEVLINK_RESOURCE_UNIT_ENTRY);
72 
73 	err = dsa_devlink_resource_register(ds, "VTU", ARRAY_SIZE(ps->vlans),
74 					    DSA_LOOP_DEVLINK_PARAM_ID_VTU,
75 					    DEVLINK_RESOURCE_ID_PARENT_TOP,
76 					    &size_params);
77 	if (err)
78 		goto out;
79 
80 	dsa_devlink_resource_occ_get_register(ds,
81 					      DSA_LOOP_DEVLINK_PARAM_ID_VTU,
82 					      dsa_loop_devlink_vtu_get, ps);
83 
84 	return 0;
85 
86 out:
87 	dsa_devlink_resources_unregister(ds);
88 	return err;
89 }
90 
91 static enum dsa_tag_protocol dsa_loop_get_protocol(struct dsa_switch *ds,
92 						   int port,
93 						   enum dsa_tag_protocol mp)
94 {
95 	dev_dbg(ds->dev, "%s: port: %d\n", __func__, port);
96 
97 	return DSA_TAG_PROTO_NONE;
98 }
99 
100 static int dsa_loop_setup(struct dsa_switch *ds)
101 {
102 	struct dsa_loop_priv *ps = ds->priv;
103 	unsigned int i;
104 
105 	for (i = 0; i < ds->num_ports; i++)
106 		memcpy(ps->ports[i].mib, dsa_loop_mibs,
107 		       sizeof(dsa_loop_mibs));
108 
109 	dev_dbg(ds->dev, "%s\n", __func__);
110 
111 	return dsa_loop_setup_devlink_resources(ds);
112 }
113 
114 static void dsa_loop_teardown(struct dsa_switch *ds)
115 {
116 	dsa_devlink_resources_unregister(ds);
117 }
118 
119 static int dsa_loop_get_sset_count(struct dsa_switch *ds, int port, int sset)
120 {
121 	if (sset != ETH_SS_STATS && sset != ETH_SS_PHY_STATS)
122 		return 0;
123 
124 	return __DSA_LOOP_CNT_MAX;
125 }
126 
127 static void dsa_loop_get_strings(struct dsa_switch *ds, int port,
128 				 u32 stringset, uint8_t *data)
129 {
130 	struct dsa_loop_priv *ps = ds->priv;
131 	unsigned int i;
132 
133 	if (stringset != ETH_SS_STATS && stringset != ETH_SS_PHY_STATS)
134 		return;
135 
136 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
137 		ethtool_puts(&data, ps->ports[port].mib[i].name);
138 }
139 
140 static void dsa_loop_get_ethtool_stats(struct dsa_switch *ds, int port,
141 				       uint64_t *data)
142 {
143 	struct dsa_loop_priv *ps = ds->priv;
144 	unsigned int i;
145 
146 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
147 		data[i] = ps->ports[port].mib[i].val;
148 }
149 
150 static int dsa_loop_phy_read(struct dsa_switch *ds, int port, int regnum)
151 {
152 	struct dsa_loop_priv *ps = ds->priv;
153 	struct mii_bus *bus = ps->bus;
154 	int ret;
155 
156 	ret = mdiobus_read_nested(bus, ps->port_base + port, regnum);
157 	if (ret < 0)
158 		ps->ports[port].mib[DSA_LOOP_PHY_READ_ERR].val++;
159 	else
160 		ps->ports[port].mib[DSA_LOOP_PHY_READ_OK].val++;
161 
162 	return ret;
163 }
164 
165 static int dsa_loop_phy_write(struct dsa_switch *ds, int port,
166 			      int regnum, u16 value)
167 {
168 	struct dsa_loop_priv *ps = ds->priv;
169 	struct mii_bus *bus = ps->bus;
170 	int ret;
171 
172 	ret = mdiobus_write_nested(bus, ps->port_base + port, regnum, value);
173 	if (ret < 0)
174 		ps->ports[port].mib[DSA_LOOP_PHY_WRITE_ERR].val++;
175 	else
176 		ps->ports[port].mib[DSA_LOOP_PHY_WRITE_OK].val++;
177 
178 	return ret;
179 }
180 
181 static int dsa_loop_port_bridge_join(struct dsa_switch *ds, int port,
182 				     struct dsa_bridge bridge,
183 				     bool *tx_fwd_offload,
184 				     struct netlink_ext_ack *extack)
185 {
186 	dev_dbg(ds->dev, "%s: port: %d, bridge: %s\n",
187 		__func__, port, bridge.dev->name);
188 
189 	return 0;
190 }
191 
192 static void dsa_loop_port_bridge_leave(struct dsa_switch *ds, int port,
193 				       struct dsa_bridge bridge)
194 {
195 	dev_dbg(ds->dev, "%s: port: %d, bridge: %s\n",
196 		__func__, port, bridge.dev->name);
197 }
198 
199 static void dsa_loop_port_stp_state_set(struct dsa_switch *ds, int port,
200 					u8 state)
201 {
202 	dev_dbg(ds->dev, "%s: port: %d, state: %d\n",
203 		__func__, port, state);
204 }
205 
206 static int dsa_loop_port_vlan_filtering(struct dsa_switch *ds, int port,
207 					bool vlan_filtering,
208 					struct netlink_ext_ack *extack)
209 {
210 	dev_dbg(ds->dev, "%s: port: %d, vlan_filtering: %d\n",
211 		__func__, port, vlan_filtering);
212 
213 	return 0;
214 }
215 
216 static int dsa_loop_port_vlan_add(struct dsa_switch *ds, int port,
217 				  const struct switchdev_obj_port_vlan *vlan,
218 				  struct netlink_ext_ack *extack)
219 {
220 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
221 	bool pvid = vlan->flags & BRIDGE_VLAN_INFO_PVID;
222 	struct dsa_loop_priv *ps = ds->priv;
223 	struct mii_bus *bus = ps->bus;
224 	struct dsa_loop_vlan *vl;
225 
226 	if (vlan->vid >= ARRAY_SIZE(ps->vlans))
227 		return -ERANGE;
228 
229 	/* Just do a sleeping operation to make lockdep checks effective */
230 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
231 
232 	vl = &ps->vlans[vlan->vid];
233 
234 	vl->members |= BIT(port);
235 	if (untagged)
236 		vl->untagged |= BIT(port);
237 	else
238 		vl->untagged &= ~BIT(port);
239 
240 	dev_dbg(ds->dev, "%s: port: %d vlan: %d, %stagged, pvid: %d\n",
241 		__func__, port, vlan->vid, untagged ? "un" : "", pvid);
242 
243 	if (pvid)
244 		ps->ports[port].pvid = vlan->vid;
245 
246 	return 0;
247 }
248 
249 static int dsa_loop_port_vlan_del(struct dsa_switch *ds, int port,
250 				  const struct switchdev_obj_port_vlan *vlan)
251 {
252 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
253 	struct dsa_loop_priv *ps = ds->priv;
254 	u16 pvid = ps->ports[port].pvid;
255 	struct mii_bus *bus = ps->bus;
256 	struct dsa_loop_vlan *vl;
257 
258 	/* Just do a sleeping operation to make lockdep checks effective */
259 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
260 
261 	vl = &ps->vlans[vlan->vid];
262 
263 	vl->members &= ~BIT(port);
264 	if (untagged)
265 		vl->untagged &= ~BIT(port);
266 
267 	if (pvid == vlan->vid)
268 		pvid = 1;
269 
270 	dev_dbg(ds->dev, "%s: port: %d vlan: %d, %stagged, pvid: %d\n",
271 		__func__, port, vlan->vid, untagged ? "un" : "", pvid);
272 	ps->ports[port].pvid = pvid;
273 
274 	return 0;
275 }
276 
277 static int dsa_loop_port_change_mtu(struct dsa_switch *ds, int port,
278 				    int new_mtu)
279 {
280 	struct dsa_loop_priv *priv = ds->priv;
281 
282 	priv->ports[port].mtu = new_mtu;
283 
284 	return 0;
285 }
286 
287 static int dsa_loop_port_max_mtu(struct dsa_switch *ds, int port)
288 {
289 	return ETH_MAX_MTU;
290 }
291 
292 static void dsa_loop_phylink_get_caps(struct dsa_switch *dsa, int port,
293 				      struct phylink_config *config)
294 {
295 	bitmap_fill(config->supported_interfaces, PHY_INTERFACE_MODE_MAX);
296 	__clear_bit(PHY_INTERFACE_MODE_NA, config->supported_interfaces);
297 	config->mac_capabilities = ~0;
298 }
299 
300 static const struct dsa_switch_ops dsa_loop_driver = {
301 	.get_tag_protocol	= dsa_loop_get_protocol,
302 	.setup			= dsa_loop_setup,
303 	.teardown		= dsa_loop_teardown,
304 	.get_strings		= dsa_loop_get_strings,
305 	.get_ethtool_stats	= dsa_loop_get_ethtool_stats,
306 	.get_sset_count		= dsa_loop_get_sset_count,
307 	.get_ethtool_phy_stats	= dsa_loop_get_ethtool_stats,
308 	.phy_read		= dsa_loop_phy_read,
309 	.phy_write		= dsa_loop_phy_write,
310 	.port_bridge_join	= dsa_loop_port_bridge_join,
311 	.port_bridge_leave	= dsa_loop_port_bridge_leave,
312 	.port_stp_state_set	= dsa_loop_port_stp_state_set,
313 	.port_vlan_filtering	= dsa_loop_port_vlan_filtering,
314 	.port_vlan_add		= dsa_loop_port_vlan_add,
315 	.port_vlan_del		= dsa_loop_port_vlan_del,
316 	.port_change_mtu	= dsa_loop_port_change_mtu,
317 	.port_max_mtu		= dsa_loop_port_max_mtu,
318 	.phylink_get_caps	= dsa_loop_phylink_get_caps,
319 };
320 
321 static int dsa_loop_drv_probe(struct mdio_device *mdiodev)
322 {
323 	struct dsa_loop_pdata *pdata = mdiodev->dev.platform_data;
324 	struct dsa_loop_priv *ps;
325 	struct dsa_switch *ds;
326 	int ret;
327 
328 	if (!pdata)
329 		return -ENODEV;
330 
331 	ds = devm_kzalloc(&mdiodev->dev, sizeof(*ds), GFP_KERNEL);
332 	if (!ds)
333 		return -ENOMEM;
334 
335 	ds->dev = &mdiodev->dev;
336 	ds->num_ports = DSA_LOOP_NUM_PORTS;
337 
338 	ps = devm_kzalloc(&mdiodev->dev, sizeof(*ps), GFP_KERNEL);
339 	if (!ps)
340 		return -ENOMEM;
341 
342 	ps->netdev = dev_get_by_name(&init_net, pdata->netdev);
343 	if (!ps->netdev)
344 		return -EPROBE_DEFER;
345 
346 	pdata->cd.netdev[DSA_LOOP_CPU_PORT] = &ps->netdev->dev;
347 
348 	ds->dev = &mdiodev->dev;
349 	ds->ops = &dsa_loop_driver;
350 	ds->priv = ps;
351 	ps->bus = mdiodev->bus;
352 
353 	dev_set_drvdata(&mdiodev->dev, ds);
354 
355 	ret = dsa_register_switch(ds);
356 	if (!ret)
357 		dev_info(&mdiodev->dev, "%s: 0x%0x\n",
358 			 pdata->name, pdata->enabled_ports);
359 
360 	return ret;
361 }
362 
363 static void dsa_loop_drv_remove(struct mdio_device *mdiodev)
364 {
365 	struct dsa_switch *ds = dev_get_drvdata(&mdiodev->dev);
366 	struct dsa_loop_priv *ps;
367 
368 	if (!ds)
369 		return;
370 
371 	ps = ds->priv;
372 
373 	dsa_unregister_switch(ds);
374 	dev_put(ps->netdev);
375 }
376 
377 static void dsa_loop_drv_shutdown(struct mdio_device *mdiodev)
378 {
379 	struct dsa_switch *ds = dev_get_drvdata(&mdiodev->dev);
380 
381 	if (!ds)
382 		return;
383 
384 	dsa_switch_shutdown(ds);
385 
386 	dev_set_drvdata(&mdiodev->dev, NULL);
387 }
388 
389 static struct mdio_driver dsa_loop_drv = {
390 	.mdiodrv.driver	= {
391 		.name	= "dsa-loop",
392 	},
393 	.probe	= dsa_loop_drv_probe,
394 	.remove	= dsa_loop_drv_remove,
395 	.shutdown = dsa_loop_drv_shutdown,
396 };
397 
398 static void dsa_loop_phydevs_unregister(void)
399 {
400 	for (int i = 0; i < NUM_FIXED_PHYS; i++) {
401 		if (!IS_ERR(phydevs[i]))
402 			fixed_phy_unregister(phydevs[i]);
403 	}
404 }
405 
406 static int __init dsa_loop_create_switch_mdiodev(void)
407 {
408 	static struct dsa_loop_pdata dsa_loop_pdata = {
409 		.cd = {
410 			.port_names[0] = "lan1",
411 			.port_names[1] = "lan2",
412 			.port_names[2] = "lan3",
413 			.port_names[3] = "lan4",
414 			.port_names[DSA_LOOP_CPU_PORT] = "cpu",
415 		},
416 		.name = "DSA mockup driver",
417 		.enabled_ports = 0x1f,
418 		.netdev = "eth0",
419 	};
420 	struct mii_bus *bus;
421 	int ret = -ENODEV;
422 
423 	bus = mdio_find_bus("fixed-0");
424 	if (WARN_ON(!bus))
425 		return ret;
426 
427 	switch_mdiodev = mdio_device_create(bus, 31);
428 	if (IS_ERR(switch_mdiodev))
429 		goto out;
430 
431 	strscpy(switch_mdiodev->modalias, "dsa-loop");
432 	switch_mdiodev->dev.platform_data = &dsa_loop_pdata;
433 
434 	ret = mdio_device_register(switch_mdiodev);
435 	if (ret)
436 		mdio_device_free(switch_mdiodev);
437 out:
438 	put_device(&bus->dev);
439 	return ret;
440 }
441 
442 static int __init dsa_loop_init(void)
443 {
444 	struct fixed_phy_status status = {
445 		.link = 1,
446 		.speed = SPEED_100,
447 		.duplex = DUPLEX_FULL,
448 	};
449 	unsigned int i;
450 	int ret;
451 
452 	ret = dsa_loop_create_switch_mdiodev();
453 	if (ret)
454 		return ret;
455 
456 	for (i = 0; i < NUM_FIXED_PHYS; i++)
457 		phydevs[i] = fixed_phy_register(&status, NULL);
458 
459 	ret = mdio_driver_register(&dsa_loop_drv);
460 	if (ret) {
461 		dsa_loop_phydevs_unregister();
462 		mdio_device_remove(switch_mdiodev);
463 		mdio_device_free(switch_mdiodev);
464 	}
465 
466 	return ret;
467 }
468 module_init(dsa_loop_init);
469 
470 static void __exit dsa_loop_exit(void)
471 {
472 	mdio_driver_unregister(&dsa_loop_drv);
473 	dsa_loop_phydevs_unregister();
474 	mdio_device_remove(switch_mdiodev);
475 	mdio_device_free(switch_mdiodev);
476 }
477 module_exit(dsa_loop_exit);
478 
479 MODULE_LICENSE("GPL");
480 MODULE_AUTHOR("Florian Fainelli");
481 MODULE_DESCRIPTION("DSA loopback driver");
482