dsa_loop.c

  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
 24struct 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
 34static 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
 41static struct phy_device *phydevs[PHY_MAX_ADDR];
 42static struct mdio_device *switch_mdiodev;
 43
 44enum dsa_loop_devlink_resource_id {
 45	DSA_LOOP_DEVLINK_PARAM_ID_VTU,
 46};
 47
 48static 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
 63static 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
 86out:
 87	dsa_devlink_resources_unregister(ds);
 88	return err;
 89}
 90
 91static 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
100static 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
114static void dsa_loop_teardown(struct dsa_switch *ds)
115{
116	dsa_devlink_resources_unregister(ds);
117}
118
119static 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
127static 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
140static 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
150static 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
165static 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
181static 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
192static 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
199static 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
206static 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
216static 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
249static 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
277static 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
287static int dsa_loop_port_max_mtu(struct dsa_switch *ds, int port)
288{
289	return ETH_MAX_MTU;
290}
291
292static 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
300static 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
321static 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
363static 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
377static 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
389static 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
398static 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
406static 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);
437out:
438	put_device(&bus->dev);
439	return ret;
440}
441
442static int __init dsa_loop_init(void)
443{
444	unsigned int i;
445	int ret;
446
447	ret = dsa_loop_create_switch_mdiodev();
448	if (ret)
449		return ret;
450
451	for (i = 0; i < NUM_FIXED_PHYS; i++)
452		phydevs[i] = fixed_phy_register_100fd();
453
454	ret = mdio_driver_register(&dsa_loop_drv);
455	if (ret) {
456		dsa_loop_phydevs_unregister();
457		mdio_device_remove(switch_mdiodev);
458		mdio_device_free(switch_mdiodev);
459	}
460
461	return ret;
462}
463module_init(dsa_loop_init);
464
465static void __exit dsa_loop_exit(void)
466{
467	mdio_driver_unregister(&dsa_loop_drv);
468	dsa_loop_phydevs_unregister();
469	mdio_device_remove(switch_mdiodev);
470	mdio_device_free(switch_mdiodev);
471}
472module_exit(dsa_loop_exit);
473
474MODULE_LICENSE("GPL");
475MODULE_AUTHOR("Florian Fainelli");
476MODULE_DESCRIPTION("DSA loopback driver");