1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Handling of a master device, switching frames via its switch fabric CPU port
4 *
5 * Copyright (c) 2017 Savoir-faire Linux Inc.
6 * Vivien Didelot <vivien.didelot@savoirfairelinux.com>
7 */
8
9 #include "dsa_priv.h"
10
dsa_master_get_regs_len(struct net_device * dev)11 static int dsa_master_get_regs_len(struct net_device *dev)
12 {
13 struct dsa_port *cpu_dp = dev->dsa_ptr;
14 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
15 struct dsa_switch *ds = cpu_dp->ds;
16 int port = cpu_dp->index;
17 int ret = 0;
18 int len;
19
20 if (ops->get_regs_len) {
21 len = ops->get_regs_len(dev);
22 if (len < 0)
23 return len;
24 ret += len;
25 }
26
27 ret += sizeof(struct ethtool_drvinfo);
28 ret += sizeof(struct ethtool_regs);
29
30 if (ds->ops->get_regs_len) {
31 len = ds->ops->get_regs_len(ds, port);
32 if (len < 0)
33 return len;
34 ret += len;
35 }
36
37 return ret;
38 }
39
dsa_master_get_regs(struct net_device * dev,struct ethtool_regs * regs,void * data)40 static void dsa_master_get_regs(struct net_device *dev,
41 struct ethtool_regs *regs, void *data)
42 {
43 struct dsa_port *cpu_dp = dev->dsa_ptr;
44 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
45 struct dsa_switch *ds = cpu_dp->ds;
46 struct ethtool_drvinfo *cpu_info;
47 struct ethtool_regs *cpu_regs;
48 int port = cpu_dp->index;
49 int len;
50
51 if (ops->get_regs_len && ops->get_regs) {
52 len = ops->get_regs_len(dev);
53 if (len < 0)
54 return;
55 regs->len = len;
56 ops->get_regs(dev, regs, data);
57 data += regs->len;
58 }
59
60 cpu_info = (struct ethtool_drvinfo *)data;
61 strlcpy(cpu_info->driver, "dsa", sizeof(cpu_info->driver));
62 data += sizeof(*cpu_info);
63 cpu_regs = (struct ethtool_regs *)data;
64 data += sizeof(*cpu_regs);
65
66 if (ds->ops->get_regs_len && ds->ops->get_regs) {
67 len = ds->ops->get_regs_len(ds, port);
68 if (len < 0)
69 return;
70 cpu_regs->len = len;
71 ds->ops->get_regs(ds, port, cpu_regs, data);
72 }
73 }
74
dsa_master_get_ethtool_stats(struct net_device * dev,struct ethtool_stats * stats,uint64_t * data)75 static void dsa_master_get_ethtool_stats(struct net_device *dev,
76 struct ethtool_stats *stats,
77 uint64_t *data)
78 {
79 struct dsa_port *cpu_dp = dev->dsa_ptr;
80 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
81 struct dsa_switch *ds = cpu_dp->ds;
82 int port = cpu_dp->index;
83 int count = 0;
84
85 if (ops->get_sset_count && ops->get_ethtool_stats) {
86 count = ops->get_sset_count(dev, ETH_SS_STATS);
87 ops->get_ethtool_stats(dev, stats, data);
88 }
89
90 if (ds->ops->get_ethtool_stats)
91 ds->ops->get_ethtool_stats(ds, port, data + count);
92 }
93
dsa_master_get_ethtool_phy_stats(struct net_device * dev,struct ethtool_stats * stats,uint64_t * data)94 static void dsa_master_get_ethtool_phy_stats(struct net_device *dev,
95 struct ethtool_stats *stats,
96 uint64_t *data)
97 {
98 struct dsa_port *cpu_dp = dev->dsa_ptr;
99 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
100 struct dsa_switch *ds = cpu_dp->ds;
101 int port = cpu_dp->index;
102 int count = 0;
103
104 if (dev->phydev && !ops->get_ethtool_phy_stats) {
105 count = phy_ethtool_get_sset_count(dev->phydev);
106 if (count >= 0)
107 phy_ethtool_get_stats(dev->phydev, stats, data);
108 } else if (ops->get_sset_count && ops->get_ethtool_phy_stats) {
109 count = ops->get_sset_count(dev, ETH_SS_PHY_STATS);
110 ops->get_ethtool_phy_stats(dev, stats, data);
111 }
112
113 if (count < 0)
114 count = 0;
115
116 if (ds->ops->get_ethtool_phy_stats)
117 ds->ops->get_ethtool_phy_stats(ds, port, data + count);
118 }
119
dsa_master_get_sset_count(struct net_device * dev,int sset)120 static int dsa_master_get_sset_count(struct net_device *dev, int sset)
121 {
122 struct dsa_port *cpu_dp = dev->dsa_ptr;
123 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
124 struct dsa_switch *ds = cpu_dp->ds;
125 int count = 0;
126
127 if (sset == ETH_SS_PHY_STATS && dev->phydev &&
128 !ops->get_ethtool_phy_stats)
129 count = phy_ethtool_get_sset_count(dev->phydev);
130 else if (ops->get_sset_count)
131 count = ops->get_sset_count(dev, sset);
132
133 if (count < 0)
134 count = 0;
135
136 if (ds->ops->get_sset_count)
137 count += ds->ops->get_sset_count(ds, cpu_dp->index, sset);
138
139 return count;
140 }
141
dsa_master_get_strings(struct net_device * dev,uint32_t stringset,uint8_t * data)142 static void dsa_master_get_strings(struct net_device *dev, uint32_t stringset,
143 uint8_t *data)
144 {
145 struct dsa_port *cpu_dp = dev->dsa_ptr;
146 const struct ethtool_ops *ops = cpu_dp->orig_ethtool_ops;
147 struct dsa_switch *ds = cpu_dp->ds;
148 int port = cpu_dp->index;
149 int len = ETH_GSTRING_LEN;
150 int mcount = 0, count;
151 unsigned int i;
152 uint8_t pfx[4];
153 uint8_t *ndata;
154
155 snprintf(pfx, sizeof(pfx), "p%.2d", port);
156 /* We do not want to be NULL-terminated, since this is a prefix */
157 pfx[sizeof(pfx) - 1] = '_';
158
159 if (stringset == ETH_SS_PHY_STATS && dev->phydev &&
160 !ops->get_ethtool_phy_stats) {
161 mcount = phy_ethtool_get_sset_count(dev->phydev);
162 if (mcount < 0)
163 mcount = 0;
164 else
165 phy_ethtool_get_strings(dev->phydev, data);
166 } else if (ops->get_sset_count && ops->get_strings) {
167 mcount = ops->get_sset_count(dev, stringset);
168 if (mcount < 0)
169 mcount = 0;
170 ops->get_strings(dev, stringset, data);
171 }
172
173 if (ds->ops->get_strings) {
174 ndata = data + mcount * len;
175 /* This function copies ETH_GSTRINGS_LEN bytes, we will mangle
176 * the output after to prepend our CPU port prefix we
177 * constructed earlier
178 */
179 ds->ops->get_strings(ds, port, stringset, ndata);
180 count = ds->ops->get_sset_count(ds, port, stringset);
181 for (i = 0; i < count; i++) {
182 memmove(ndata + (i * len + sizeof(pfx)),
183 ndata + i * len, len - sizeof(pfx));
184 memcpy(ndata + i * len, pfx, sizeof(pfx));
185 }
186 }
187 }
188
dsa_master_get_phys_port_name(struct net_device * dev,char * name,size_t len)189 static int dsa_master_get_phys_port_name(struct net_device *dev,
190 char *name, size_t len)
191 {
192 struct dsa_port *cpu_dp = dev->dsa_ptr;
193
194 if (snprintf(name, len, "p%d", cpu_dp->index) >= len)
195 return -EINVAL;
196
197 return 0;
198 }
199
dsa_master_ethtool_setup(struct net_device * dev)200 static int dsa_master_ethtool_setup(struct net_device *dev)
201 {
202 struct dsa_port *cpu_dp = dev->dsa_ptr;
203 struct dsa_switch *ds = cpu_dp->ds;
204 struct ethtool_ops *ops;
205
206 ops = devm_kzalloc(ds->dev, sizeof(*ops), GFP_KERNEL);
207 if (!ops)
208 return -ENOMEM;
209
210 cpu_dp->orig_ethtool_ops = dev->ethtool_ops;
211 if (cpu_dp->orig_ethtool_ops)
212 memcpy(ops, cpu_dp->orig_ethtool_ops, sizeof(*ops));
213
214 ops->get_regs_len = dsa_master_get_regs_len;
215 ops->get_regs = dsa_master_get_regs;
216 ops->get_sset_count = dsa_master_get_sset_count;
217 ops->get_ethtool_stats = dsa_master_get_ethtool_stats;
218 ops->get_strings = dsa_master_get_strings;
219 ops->get_ethtool_phy_stats = dsa_master_get_ethtool_phy_stats;
220
221 dev->ethtool_ops = ops;
222
223 return 0;
224 }
225
dsa_master_ethtool_teardown(struct net_device * dev)226 static void dsa_master_ethtool_teardown(struct net_device *dev)
227 {
228 struct dsa_port *cpu_dp = dev->dsa_ptr;
229
230 dev->ethtool_ops = cpu_dp->orig_ethtool_ops;
231 cpu_dp->orig_ethtool_ops = NULL;
232 }
233
dsa_master_ndo_setup(struct net_device * dev)234 static int dsa_master_ndo_setup(struct net_device *dev)
235 {
236 struct dsa_port *cpu_dp = dev->dsa_ptr;
237 struct dsa_switch *ds = cpu_dp->ds;
238 struct net_device_ops *ops;
239
240 if (dev->netdev_ops->ndo_get_phys_port_name)
241 return 0;
242
243 ops = devm_kzalloc(ds->dev, sizeof(*ops), GFP_KERNEL);
244 if (!ops)
245 return -ENOMEM;
246
247 cpu_dp->orig_ndo_ops = dev->netdev_ops;
248 if (cpu_dp->orig_ndo_ops)
249 memcpy(ops, cpu_dp->orig_ndo_ops, sizeof(*ops));
250
251 ops->ndo_get_phys_port_name = dsa_master_get_phys_port_name;
252
253 dev->netdev_ops = ops;
254
255 return 0;
256 }
257
dsa_master_ndo_teardown(struct net_device * dev)258 static void dsa_master_ndo_teardown(struct net_device *dev)
259 {
260 struct dsa_port *cpu_dp = dev->dsa_ptr;
261
262 dev->netdev_ops = cpu_dp->orig_ndo_ops;
263 cpu_dp->orig_ndo_ops = NULL;
264 }
265
tagging_show(struct device * d,struct device_attribute * attr,char * buf)266 static ssize_t tagging_show(struct device *d, struct device_attribute *attr,
267 char *buf)
268 {
269 struct net_device *dev = to_net_dev(d);
270 struct dsa_port *cpu_dp = dev->dsa_ptr;
271
272 return sprintf(buf, "%s\n",
273 dsa_tag_protocol_to_str(cpu_dp->tag_ops));
274 }
275 static DEVICE_ATTR_RO(tagging);
276
277 static struct attribute *dsa_slave_attrs[] = {
278 &dev_attr_tagging.attr,
279 NULL
280 };
281
282 static const struct attribute_group dsa_group = {
283 .name = "dsa",
284 .attrs = dsa_slave_attrs,
285 };
286
dsa_master_set_mtu(struct net_device * dev,struct dsa_port * cpu_dp)287 static void dsa_master_set_mtu(struct net_device *dev, struct dsa_port *cpu_dp)
288 {
289 unsigned int mtu = ETH_DATA_LEN + cpu_dp->tag_ops->overhead;
290 int err;
291
292 rtnl_lock();
293 if (mtu <= dev->max_mtu) {
294 err = dev_set_mtu(dev, mtu);
295 if (err)
296 netdev_dbg(dev, "Unable to set MTU to include for DSA overheads\n");
297 }
298 rtnl_unlock();
299 }
300
dsa_master_reset_mtu(struct net_device * dev)301 static void dsa_master_reset_mtu(struct net_device *dev)
302 {
303 int err;
304
305 rtnl_lock();
306 err = dev_set_mtu(dev, ETH_DATA_LEN);
307 if (err)
308 netdev_dbg(dev,
309 "Unable to reset MTU to exclude DSA overheads\n");
310 rtnl_unlock();
311 }
312
dsa_master_setup(struct net_device * dev,struct dsa_port * cpu_dp)313 int dsa_master_setup(struct net_device *dev, struct dsa_port *cpu_dp)
314 {
315 int ret;
316
317 dsa_master_set_mtu(dev, cpu_dp);
318
319 /* If we use a tagging format that doesn't have an ethertype
320 * field, make sure that all packets from this point on get
321 * sent to the tag format's receive function.
322 */
323 wmb();
324
325 dev->dsa_ptr = cpu_dp;
326 ret = dsa_master_ethtool_setup(dev);
327 if (ret)
328 return ret;
329
330 ret = dsa_master_ndo_setup(dev);
331 if (ret)
332 goto out_err_ethtool_teardown;
333
334 ret = sysfs_create_group(&dev->dev.kobj, &dsa_group);
335 if (ret)
336 goto out_err_ndo_teardown;
337
338 return ret;
339
340 out_err_ndo_teardown:
341 dsa_master_ndo_teardown(dev);
342 out_err_ethtool_teardown:
343 dsa_master_ethtool_teardown(dev);
344 return ret;
345 }
346
dsa_master_teardown(struct net_device * dev)347 void dsa_master_teardown(struct net_device *dev)
348 {
349 sysfs_remove_group(&dev->dev.kobj, &dsa_group);
350 dsa_master_ndo_teardown(dev);
351 dsa_master_ethtool_teardown(dev);
352 dsa_master_reset_mtu(dev);
353
354 dev->dsa_ptr = NULL;
355
356 /* If we used a tagging format that doesn't have an ethertype
357 * field, make sure that all packets from this point get sent
358 * without the tag and go through the regular receive path.
359 */
360 wmb();
361 }
362