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
22static 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
29static struct phy_device *phydevs[PHY_MAX_ADDR];
30
31enum dsa_loop_devlink_resource_id {
32	DSA_LOOP_DEVLINK_PARAM_ID_VTU,
33};
34
35static 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
50static 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
73out:
74	dsa_devlink_resources_unregister(ds);
75	return err;
76}
77
78static 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
87static 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
101static void dsa_loop_teardown(struct dsa_switch *ds)
102{
103	dsa_devlink_resources_unregister(ds);
104}
105
106static 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
114static 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
128static 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
138static 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
153static 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
169static int dsa_loop_port_bridge_join(struct dsa_switch *ds, int port,
170				     struct net_device *bridge)
171{
172	dev_dbg(ds->dev, "%s: port: %d, bridge: %s\n",
173		__func__, port, bridge->name);
174
175	return 0;
176}
177
178static void dsa_loop_port_bridge_leave(struct dsa_switch *ds, int port,
179				       struct net_device *bridge)
180{
181	dev_dbg(ds->dev, "%s: port: %d, bridge: %s\n",
182		__func__, port, bridge->name);
183}
184
185static void dsa_loop_port_stp_state_set(struct dsa_switch *ds, int port,
186					u8 state)
187{
188	dev_dbg(ds->dev, "%s: port: %d, state: %d\n",
189		__func__, port, state);
190}
191
192static int dsa_loop_port_vlan_filtering(struct dsa_switch *ds, int port,
193					bool vlan_filtering,
194					struct switchdev_trans *trans)
195{
196	dev_dbg(ds->dev, "%s: port: %d, vlan_filtering: %d\n",
197		__func__, port, vlan_filtering);
198
199	return 0;
200}
201
202static int
203dsa_loop_port_vlan_prepare(struct dsa_switch *ds, int port,
204			   const struct switchdev_obj_port_vlan *vlan)
205{
206	struct dsa_loop_priv *ps = ds->priv;
207	struct mii_bus *bus = ps->bus;
208
209	dev_dbg(ds->dev, "%s: port: %d, vlan: %d-%d",
210		__func__, port, vlan->vid_begin, vlan->vid_end);
211
212	/* Just do a sleeping operation to make lockdep checks effective */
213	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
214
215	if (vlan->vid_end > ARRAY_SIZE(ps->vlans))
216		return -ERANGE;
217
218	return 0;
219}
220
221static void dsa_loop_port_vlan_add(struct dsa_switch *ds, int port,
222				   const struct switchdev_obj_port_vlan *vlan)
223{
224	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
225	bool pvid = vlan->flags & BRIDGE_VLAN_INFO_PVID;
226	struct dsa_loop_priv *ps = ds->priv;
227	struct mii_bus *bus = ps->bus;
228	struct dsa_loop_vlan *vl;
229	u16 vid;
230
231	/* Just do a sleeping operation to make lockdep checks effective */
232	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
233
234	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
235		vl = &ps->vlans[vid];
236
237		vl->members |= BIT(port);
238		if (untagged)
239			vl->untagged |= BIT(port);
240		else
241			vl->untagged &= ~BIT(port);
242
243		dev_dbg(ds->dev, "%s: port: %d vlan: %d, %stagged, pvid: %d\n",
244			__func__, port, vid, untagged ? "un" : "", pvid);
245	}
246
247	if (pvid)
248		ps->ports[port].pvid = vid;
249}
250
251static int dsa_loop_port_vlan_del(struct dsa_switch *ds, int port,
252				  const struct switchdev_obj_port_vlan *vlan)
253{
254	bool untagged = vlan->flags & BRIDGE_VLAN_INFO_UNTAGGED;
255	struct dsa_loop_priv *ps = ds->priv;
256	struct mii_bus *bus = ps->bus;
257	struct dsa_loop_vlan *vl;
258	u16 vid, pvid = ps->ports[port].pvid;
259
260	/* Just do a sleeping operation to make lockdep checks effective */
261	mdiobus_read(bus, ps->port_base + port, MII_BMSR);
262
263	for (vid = vlan->vid_begin; vid <= vlan->vid_end; ++vid) {
264		vl = &ps->vlans[vid];
265
266		vl->members &= ~BIT(port);
267		if (untagged)
268			vl->untagged &= ~BIT(port);
269
270		if (pvid == vid)
271			pvid = 1;
272
273		dev_dbg(ds->dev, "%s: port: %d vlan: %d, %stagged, pvid: %d\n",
274			__func__, port, vid, untagged ? "un" : "", pvid);
275	}
276	ps->ports[port].pvid = pvid;
277
278	return 0;
279}
280
281static int dsa_loop_port_change_mtu(struct dsa_switch *ds, int port,
282				    int new_mtu)
283{
284	struct dsa_loop_priv *priv = ds->priv;
285
286	priv->ports[port].mtu = new_mtu;
287
288	return 0;
289}
290
291static int dsa_loop_port_max_mtu(struct dsa_switch *ds, int port)
292{
293	return ETH_MAX_MTU;
294}
295
296static const struct dsa_switch_ops dsa_loop_driver = {
297	.get_tag_protocol	= dsa_loop_get_protocol,
298	.setup			= dsa_loop_setup,
299	.teardown		= dsa_loop_teardown,
300	.get_strings		= dsa_loop_get_strings,
301	.get_ethtool_stats	= dsa_loop_get_ethtool_stats,
302	.get_sset_count		= dsa_loop_get_sset_count,
303	.get_ethtool_phy_stats	= dsa_loop_get_ethtool_stats,
304	.phy_read		= dsa_loop_phy_read,
305	.phy_write		= dsa_loop_phy_write,
306	.port_bridge_join	= dsa_loop_port_bridge_join,
307	.port_bridge_leave	= dsa_loop_port_bridge_leave,
308	.port_stp_state_set	= dsa_loop_port_stp_state_set,
309	.port_vlan_filtering	= dsa_loop_port_vlan_filtering,
310	.port_vlan_prepare	= dsa_loop_port_vlan_prepare,
311	.port_vlan_add		= dsa_loop_port_vlan_add,
312	.port_vlan_del		= dsa_loop_port_vlan_del,
313	.port_change_mtu	= dsa_loop_port_change_mtu,
314	.port_max_mtu		= dsa_loop_port_max_mtu,
315};
316
317static int dsa_loop_drv_probe(struct mdio_device *mdiodev)
318{
319	struct dsa_loop_pdata *pdata = mdiodev->dev.platform_data;
320	struct dsa_loop_priv *ps;
321	struct dsa_switch *ds;
322	int ret;
323
324	if (!pdata)
325		return -ENODEV;
326
327	ds = devm_kzalloc(&mdiodev->dev, sizeof(*ds), GFP_KERNEL);
328	if (!ds)
329		return -ENOMEM;
330
331	ds->dev = &mdiodev->dev;
332	ds->num_ports = DSA_LOOP_NUM_PORTS;
333
334	ps = devm_kzalloc(&mdiodev->dev, sizeof(*ps), GFP_KERNEL);
335	if (!ps)
336		return -ENOMEM;
337
338	ps->netdev = dev_get_by_name(&init_net, pdata->netdev);
339	if (!ps->netdev)
340		return -EPROBE_DEFER;
341
342	pdata->cd.netdev[DSA_LOOP_CPU_PORT] = &ps->netdev->dev;
343
344	ds->dev = &mdiodev->dev;
345	ds->ops = &dsa_loop_driver;
346	ds->priv = ps;
347	ds->configure_vlan_while_not_filtering = true;
348	ps->bus = mdiodev->bus;
349
350	dev_set_drvdata(&mdiodev->dev, ds);
351
352	ret = dsa_register_switch(ds);
353	if (!ret)
354		dev_info(&mdiodev->dev, "%s: 0x%0x\n",
355			 pdata->name, pdata->enabled_ports);
356
357	return ret;
358}
359
360static void dsa_loop_drv_remove(struct mdio_device *mdiodev)
361{
362	struct dsa_switch *ds = dev_get_drvdata(&mdiodev->dev);
363	struct dsa_loop_priv *ps = ds->priv;
364
365	dsa_unregister_switch(ds);
366	dev_put(ps->netdev);
367}
368
369static struct mdio_driver dsa_loop_drv = {
370	.mdiodrv.driver	= {
371		.name	= "dsa-loop",
372	},
373	.probe	= dsa_loop_drv_probe,
374	.remove	= dsa_loop_drv_remove,
375};
376
377#define NUM_FIXED_PHYS	(DSA_LOOP_NUM_PORTS - 2)
378
379static 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
390static 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}
408module_init(dsa_loop_init);
409
410static void __exit dsa_loop_exit(void)
411{
412	mdio_driver_unregister(&dsa_loop_drv);
413	dsa_loop_phydevs_unregister();
414}
415module_exit(dsa_loop_exit);
416
417MODULE_SOFTDEP("pre: dsa_loop_bdinfo");
418MODULE_LICENSE("GPL");
419MODULE_AUTHOR("Florian Fainelli");
420MODULE_DESCRIPTION("DSA loopback driver");
421