xref: /openbmc/linux/drivers/net/dsa/dsa_loop.c (revision 0c6dfa75)
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 #include "dsa_loop.h"
21 
22 static struct dsa_loop_mib_entry dsa_loop_mibs[] = {
23 	[DSA_LOOP_PHY_READ_OK]	= { "phy_read_ok", },
24 	[DSA_LOOP_PHY_READ_ERR]	= { "phy_read_err", },
25 	[DSA_LOOP_PHY_WRITE_OK] = { "phy_write_ok", },
26 	[DSA_LOOP_PHY_WRITE_ERR] = { "phy_write_err", },
27 };
28 
29 static struct phy_device *phydevs[PHY_MAX_ADDR];
30 
31 enum dsa_loop_devlink_resource_id {
32 	DSA_LOOP_DEVLINK_PARAM_ID_VTU,
33 };
34 
35 static u64 dsa_loop_devlink_vtu_get(void *priv)
36 {
37 	struct dsa_loop_priv *ps = priv;
38 	unsigned int i, count = 0;
39 	struct dsa_loop_vlan *vl;
40 
41 	for (i = 0; i < ARRAY_SIZE(ps->vlans); i++) {
42 		vl = &ps->vlans[i];
43 		if (vl->members)
44 			count++;
45 	}
46 
47 	return count;
48 }
49 
50 static int dsa_loop_setup_devlink_resources(struct dsa_switch *ds)
51 {
52 	struct devlink_resource_size_params size_params;
53 	struct dsa_loop_priv *ps = ds->priv;
54 	int err;
55 
56 	devlink_resource_size_params_init(&size_params, ARRAY_SIZE(ps->vlans),
57 					  ARRAY_SIZE(ps->vlans),
58 					  1, DEVLINK_RESOURCE_UNIT_ENTRY);
59 
60 	err = dsa_devlink_resource_register(ds, "VTU", ARRAY_SIZE(ps->vlans),
61 					    DSA_LOOP_DEVLINK_PARAM_ID_VTU,
62 					    DEVLINK_RESOURCE_ID_PARENT_TOP,
63 					    &size_params);
64 	if (err)
65 		goto out;
66 
67 	dsa_devlink_resource_occ_get_register(ds,
68 					      DSA_LOOP_DEVLINK_PARAM_ID_VTU,
69 					      dsa_loop_devlink_vtu_get, ps);
70 
71 	return 0;
72 
73 out:
74 	dsa_devlink_resources_unregister(ds);
75 	return err;
76 }
77 
78 static enum dsa_tag_protocol dsa_loop_get_protocol(struct dsa_switch *ds,
79 						   int port,
80 						   enum dsa_tag_protocol mp)
81 {
82 	dev_dbg(ds->dev, "%s: port: %d\n", __func__, port);
83 
84 	return DSA_TAG_PROTO_NONE;
85 }
86 
87 static int dsa_loop_setup(struct dsa_switch *ds)
88 {
89 	struct dsa_loop_priv *ps = ds->priv;
90 	unsigned int i;
91 
92 	for (i = 0; i < ds->num_ports; i++)
93 		memcpy(ps->ports[i].mib, dsa_loop_mibs,
94 		       sizeof(dsa_loop_mibs));
95 
96 	dev_dbg(ds->dev, "%s\n", __func__);
97 
98 	return dsa_loop_setup_devlink_resources(ds);
99 }
100 
101 static void dsa_loop_teardown(struct dsa_switch *ds)
102 {
103 	dsa_devlink_resources_unregister(ds);
104 }
105 
106 static int dsa_loop_get_sset_count(struct dsa_switch *ds, int port, int sset)
107 {
108 	if (sset != ETH_SS_STATS && sset != ETH_SS_PHY_STATS)
109 		return 0;
110 
111 	return __DSA_LOOP_CNT_MAX;
112 }
113 
114 static void dsa_loop_get_strings(struct dsa_switch *ds, int port,
115 				 u32 stringset, uint8_t *data)
116 {
117 	struct dsa_loop_priv *ps = ds->priv;
118 	unsigned int i;
119 
120 	if (stringset != ETH_SS_STATS && stringset != ETH_SS_PHY_STATS)
121 		return;
122 
123 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
124 		memcpy(data + i * ETH_GSTRING_LEN,
125 		       ps->ports[port].mib[i].name, ETH_GSTRING_LEN);
126 }
127 
128 static void dsa_loop_get_ethtool_stats(struct dsa_switch *ds, int port,
129 				       uint64_t *data)
130 {
131 	struct dsa_loop_priv *ps = ds->priv;
132 	unsigned int i;
133 
134 	for (i = 0; i < __DSA_LOOP_CNT_MAX; i++)
135 		data[i] = ps->ports[port].mib[i].val;
136 }
137 
138 static int dsa_loop_phy_read(struct dsa_switch *ds, int port, int regnum)
139 {
140 	struct dsa_loop_priv *ps = ds->priv;
141 	struct mii_bus *bus = ps->bus;
142 	int ret;
143 
144 	ret = mdiobus_read_nested(bus, ps->port_base + port, regnum);
145 	if (ret < 0)
146 		ps->ports[port].mib[DSA_LOOP_PHY_READ_ERR].val++;
147 	else
148 		ps->ports[port].mib[DSA_LOOP_PHY_READ_OK].val++;
149 
150 	return ret;
151 }
152 
153 static int dsa_loop_phy_write(struct dsa_switch *ds, int port,
154 			      int regnum, u16 value)
155 {
156 	struct dsa_loop_priv *ps = ds->priv;
157 	struct mii_bus *bus = ps->bus;
158 	int ret;
159 
160 	ret = mdiobus_write_nested(bus, ps->port_base + port, regnum, value);
161 	if (ret < 0)
162 		ps->ports[port].mib[DSA_LOOP_PHY_WRITE_ERR].val++;
163 	else
164 		ps->ports[port].mib[DSA_LOOP_PHY_WRITE_OK].val++;
165 
166 	return ret;
167 }
168 
169 static int dsa_loop_port_bridge_join(struct dsa_switch *ds, int port,
170 				     struct dsa_bridge bridge,
171 				     bool *tx_fwd_offload,
172 				     struct netlink_ext_ack *extack)
173 {
174 	dev_dbg(ds->dev, "%s: port: %d, bridge: %s\n",
175 		__func__, port, bridge.dev->name);
176 
177 	return 0;
178 }
179 
180 static void dsa_loop_port_bridge_leave(struct dsa_switch *ds, int port,
181 				       struct dsa_bridge bridge)
182 {
183 	dev_dbg(ds->dev, "%s: port: %d, bridge: %s\n",
184 		__func__, port, bridge.dev->name);
185 }
186 
187 static void dsa_loop_port_stp_state_set(struct dsa_switch *ds, int port,
188 					u8 state)
189 {
190 	dev_dbg(ds->dev, "%s: port: %d, state: %d\n",
191 		__func__, port, state);
192 }
193 
194 static int dsa_loop_port_vlan_filtering(struct dsa_switch *ds, int port,
195 					bool vlan_filtering,
196 					struct netlink_ext_ack *extack)
197 {
198 	dev_dbg(ds->dev, "%s: port: %d, vlan_filtering: %d\n",
199 		__func__, port, vlan_filtering);
200 
201 	return 0;
202 }
203 
204 static int dsa_loop_port_vlan_add(struct dsa_switch *ds, int port,
205 				  const struct switchdev_obj_port_vlan *vlan,
206 				  struct netlink_ext_ack *extack)
207 {
208 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
209 	bool pvid = vlan->flags & BRIDGE_VLAN_INFO_PVID;
210 	struct dsa_loop_priv *ps = ds->priv;
211 	struct mii_bus *bus = ps->bus;
212 	struct dsa_loop_vlan *vl;
213 
214 	if (vlan->vid >= ARRAY_SIZE(ps->vlans))
215 		return -ERANGE;
216 
217 	/* Just do a sleeping operation to make lockdep checks effective */
218 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
219 
220 	vl = &ps->vlans[vlan->vid];
221 
222 	vl->members |= BIT(port);
223 	if (untagged)
224 		vl->untagged |= BIT(port);
225 	else
226 		vl->untagged &= ~BIT(port);
227 
228 	dev_dbg(ds->dev, "%s: port: %d vlan: %d, %stagged, pvid: %d\n",
229 		__func__, port, vlan->vid, untagged ? "un" : "", pvid);
230 
231 	if (pvid)
232 		ps->ports[port].pvid = vlan->vid;
233 
234 	return 0;
235 }
236 
237 static int dsa_loop_port_vlan_del(struct dsa_switch *ds, int port,
238 				  const struct switchdev_obj_port_vlan *vlan)
239 {
240 	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
241 	struct dsa_loop_priv *ps = ds->priv;
242 	u16 pvid = ps->ports[port].pvid;
243 	struct mii_bus *bus = ps->bus;
244 	struct dsa_loop_vlan *vl;
245 
246 	/* Just do a sleeping operation to make lockdep checks effective */
247 	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
248 
249 	vl = &ps->vlans[vlan->vid];
250 
251 	vl->members &= ~BIT(port);
252 	if (untagged)
253 		vl->untagged &= ~BIT(port);
254 
255 	if (pvid == vlan->vid)
256 		pvid = 1;
257 
258 	dev_dbg(ds->dev, "%s: port: %d vlan: %d, %stagged, pvid: %d\n",
259 		__func__, port, vlan->vid, untagged ? "un" : "", pvid);
260 	ps->ports[port].pvid = pvid;
261 
262 	return 0;
263 }
264 
265 static int dsa_loop_port_change_mtu(struct dsa_switch *ds, int port,
266 				    int new_mtu)
267 {
268 	struct dsa_loop_priv *priv = ds->priv;
269 
270 	priv->ports[port].mtu = new_mtu;
271 
272 	return 0;
273 }
274 
275 static int dsa_loop_port_max_mtu(struct dsa_switch *ds, int port)
276 {
277 	return ETH_MAX_MTU;
278 }
279 
280 static const struct dsa_switch_ops dsa_loop_driver = {
281 	.get_tag_protocol	= dsa_loop_get_protocol,
282 	.setup			= dsa_loop_setup,
283 	.teardown		= dsa_loop_teardown,
284 	.get_strings		= dsa_loop_get_strings,
285 	.get_ethtool_stats	= dsa_loop_get_ethtool_stats,
286 	.get_sset_count		= dsa_loop_get_sset_count,
287 	.get_ethtool_phy_stats	= dsa_loop_get_ethtool_stats,
288 	.phy_read		= dsa_loop_phy_read,
289 	.phy_write		= dsa_loop_phy_write,
290 	.port_bridge_join	= dsa_loop_port_bridge_join,
291 	.port_bridge_leave	= dsa_loop_port_bridge_leave,
292 	.port_stp_state_set	= dsa_loop_port_stp_state_set,
293 	.port_vlan_filtering	= dsa_loop_port_vlan_filtering,
294 	.port_vlan_add		= dsa_loop_port_vlan_add,
295 	.port_vlan_del		= dsa_loop_port_vlan_del,
296 	.port_change_mtu	= dsa_loop_port_change_mtu,
297 	.port_max_mtu		= dsa_loop_port_max_mtu,
298 };
299 
300 static int dsa_loop_drv_probe(struct mdio_device *mdiodev)
301 {
302 	struct dsa_loop_pdata *pdata = mdiodev->dev.platform_data;
303 	struct dsa_loop_priv *ps;
304 	struct dsa_switch *ds;
305 	int ret;
306 
307 	if (!pdata)
308 		return -ENODEV;
309 
310 	ds = devm_kzalloc(&mdiodev->dev, sizeof(*ds), GFP_KERNEL);
311 	if (!ds)
312 		return -ENOMEM;
313 
314 	ds->dev = &mdiodev->dev;
315 	ds->num_ports = DSA_LOOP_NUM_PORTS;
316 
317 	ps = devm_kzalloc(&mdiodev->dev, sizeof(*ps), GFP_KERNEL);
318 	if (!ps)
319 		return -ENOMEM;
320 
321 	ps->netdev = dev_get_by_name(&init_net, pdata->netdev);
322 	if (!ps->netdev)
323 		return -EPROBE_DEFER;
324 
325 	pdata->cd.netdev[DSA_LOOP_CPU_PORT] = &ps->netdev->dev;
326 
327 	ds->dev = &mdiodev->dev;
328 	ds->ops = &dsa_loop_driver;
329 	ds->priv = ps;
330 	ps->bus = mdiodev->bus;
331 
332 	dev_set_drvdata(&mdiodev->dev, ds);
333 
334 	ret = dsa_register_switch(ds);
335 	if (!ret)
336 		dev_info(&mdiodev->dev, "%s: 0x%0x\n",
337 			 pdata->name, pdata->enabled_ports);
338 
339 	return ret;
340 }
341 
342 static void dsa_loop_drv_remove(struct mdio_device *mdiodev)
343 {
344 	struct dsa_switch *ds = dev_get_drvdata(&mdiodev->dev);
345 	struct dsa_loop_priv *ps;
346 
347 	if (!ds)
348 		return;
349 
350 	ps = ds->priv;
351 
352 	dsa_unregister_switch(ds);
353 	dev_put(ps->netdev);
354 }
355 
356 static void dsa_loop_drv_shutdown(struct mdio_device *mdiodev)
357 {
358 	struct dsa_switch *ds = dev_get_drvdata(&mdiodev->dev);
359 
360 	if (!ds)
361 		return;
362 
363 	dsa_switch_shutdown(ds);
364 
365 	dev_set_drvdata(&mdiodev->dev, NULL);
366 }
367 
368 static struct mdio_driver dsa_loop_drv = {
369 	.mdiodrv.driver	= {
370 		.name	= "dsa-loop",
371 	},
372 	.probe	= dsa_loop_drv_probe,
373 	.remove	= dsa_loop_drv_remove,
374 	.shutdown = dsa_loop_drv_shutdown,
375 };
376 
377 #define NUM_FIXED_PHYS	(DSA_LOOP_NUM_PORTS - 2)
378 
379 static void dsa_loop_phydevs_unregister(void)
380 {
381 	unsigned int i;
382 
383 	for (i = 0; i < NUM_FIXED_PHYS; i++)
384 		if (!IS_ERR(phydevs[i])) {
385 			fixed_phy_unregister(phydevs[i]);
386 			phy_device_free(phydevs[i]);
387 		}
388 }
389 
390 static int __init dsa_loop_init(void)
391 {
392 	struct fixed_phy_status status = {
393 		.link = 1,
394 		.speed = SPEED_100,
395 		.duplex = DUPLEX_FULL,
396 	};
397 	unsigned int i, ret;
398 
399 	for (i = 0; i < NUM_FIXED_PHYS; i++)
400 		phydevs[i] = fixed_phy_register(PHY_POLL, &status, NULL);
401 
402 	ret = mdio_driver_register(&dsa_loop_drv);
403 	if (ret)
404 		dsa_loop_phydevs_unregister();
405 
406 	return ret;
407 }
408 module_init(dsa_loop_init);
409 
410 static void __exit dsa_loop_exit(void)
411 {
412 	mdio_driver_unregister(&dsa_loop_drv);
413 	dsa_loop_phydevs_unregister();
414 }
415 module_exit(dsa_loop_exit);
416 
417 MODULE_SOFTDEP("pre: dsa_loop_bdinfo");
418 MODULE_LICENSE("GPL");
419 MODULE_AUTHOR("Florian Fainelli");
420 MODULE_DESCRIPTION("DSA loopback driver");
421