1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * net/dsa/tag_ksz.c - Microchip KSZ Switch tag format handling
4 * Copyright (c) 2017 Microchip Technology
5 */
6
7 #include <linux/dsa/ksz_common.h>
8 #include <linux/etherdevice.h>
9 #include <linux/list.h>
10 #include <linux/ptp_classify.h>
11 #include <net/dsa.h>
12
13 #include "tag.h"
14
15 #define KSZ8795_NAME "ksz8795"
16 #define KSZ9477_NAME "ksz9477"
17 #define KSZ9893_NAME "ksz9893"
18 #define LAN937X_NAME "lan937x"
19
20 /* Typically only one byte is used for tail tag. */
21 #define KSZ_PTP_TAG_LEN 4
22 #define KSZ_EGRESS_TAG_LEN 1
23 #define KSZ_INGRESS_TAG_LEN 1
24
25 #define KSZ_HWTS_EN 0
26
27 struct ksz_tagger_private {
28 struct ksz_tagger_data data; /* Must be first */
29 unsigned long state;
30 struct kthread_worker *xmit_worker;
31 };
32
33 static struct ksz_tagger_private *
ksz_tagger_private(struct dsa_switch * ds)34 ksz_tagger_private(struct dsa_switch *ds)
35 {
36 return ds->tagger_data;
37 }
38
ksz_hwtstamp_set_state(struct dsa_switch * ds,bool on)39 static void ksz_hwtstamp_set_state(struct dsa_switch *ds, bool on)
40 {
41 struct ksz_tagger_private *priv = ksz_tagger_private(ds);
42
43 if (on)
44 set_bit(KSZ_HWTS_EN, &priv->state);
45 else
46 clear_bit(KSZ_HWTS_EN, &priv->state);
47 }
48
ksz_disconnect(struct dsa_switch * ds)49 static void ksz_disconnect(struct dsa_switch *ds)
50 {
51 struct ksz_tagger_private *priv = ds->tagger_data;
52
53 kthread_destroy_worker(priv->xmit_worker);
54 kfree(priv);
55 ds->tagger_data = NULL;
56 }
57
ksz_connect(struct dsa_switch * ds)58 static int ksz_connect(struct dsa_switch *ds)
59 {
60 struct ksz_tagger_data *tagger_data;
61 struct kthread_worker *xmit_worker;
62 struct ksz_tagger_private *priv;
63 int ret;
64
65 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
66 if (!priv)
67 return -ENOMEM;
68
69 xmit_worker = kthread_create_worker(0, "dsa%d:%d_xmit",
70 ds->dst->index, ds->index);
71 if (IS_ERR(xmit_worker)) {
72 ret = PTR_ERR(xmit_worker);
73 kfree(priv);
74 return ret;
75 }
76
77 priv->xmit_worker = xmit_worker;
78 /* Export functions for switch driver use */
79 tagger_data = &priv->data;
80 tagger_data->hwtstamp_set_state = ksz_hwtstamp_set_state;
81 ds->tagger_data = priv;
82
83 return 0;
84 }
85
ksz_common_rcv(struct sk_buff * skb,struct net_device * dev,unsigned int port,unsigned int len)86 static struct sk_buff *ksz_common_rcv(struct sk_buff *skb,
87 struct net_device *dev,
88 unsigned int port, unsigned int len)
89 {
90 skb->dev = dsa_master_find_slave(dev, 0, port);
91 if (!skb->dev)
92 return NULL;
93
94 if (pskb_trim_rcsum(skb, skb->len - len))
95 return NULL;
96
97 dsa_default_offload_fwd_mark(skb);
98
99 return skb;
100 }
101
102 /*
103 * For Ingress (Host -> KSZ8795), 1 byte is added before FCS.
104 * ---------------------------------------------------------------------------
105 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag(1byte)|FCS(4bytes)
106 * ---------------------------------------------------------------------------
107 * tag : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
108 *
109 * For Egress (KSZ8795 -> Host), 1 byte is added before FCS.
110 * ---------------------------------------------------------------------------
111 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
112 * ---------------------------------------------------------------------------
113 * tag0 : zero-based value represents port
114 * (eg, 0x00=port1, 0x02=port3, 0x06=port7)
115 */
116
117 #define KSZ8795_TAIL_TAG_OVERRIDE BIT(6)
118 #define KSZ8795_TAIL_TAG_LOOKUP BIT(7)
119
ksz8795_xmit(struct sk_buff * skb,struct net_device * dev)120 static struct sk_buff *ksz8795_xmit(struct sk_buff *skb, struct net_device *dev)
121 {
122 struct dsa_port *dp = dsa_slave_to_port(dev);
123 struct ethhdr *hdr;
124 u8 *tag;
125
126 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
127 return NULL;
128
129 /* Tag encoding */
130 tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);
131 hdr = skb_eth_hdr(skb);
132
133 *tag = 1 << dp->index;
134 if (is_link_local_ether_addr(hdr->h_dest))
135 *tag |= KSZ8795_TAIL_TAG_OVERRIDE;
136
137 return skb;
138 }
139
ksz8795_rcv(struct sk_buff * skb,struct net_device * dev)140 static struct sk_buff *ksz8795_rcv(struct sk_buff *skb, struct net_device *dev)
141 {
142 u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
143
144 return ksz_common_rcv(skb, dev, tag[0] & 7, KSZ_EGRESS_TAG_LEN);
145 }
146
147 static const struct dsa_device_ops ksz8795_netdev_ops = {
148 .name = KSZ8795_NAME,
149 .proto = DSA_TAG_PROTO_KSZ8795,
150 .xmit = ksz8795_xmit,
151 .rcv = ksz8795_rcv,
152 .needed_tailroom = KSZ_INGRESS_TAG_LEN,
153 };
154
155 DSA_TAG_DRIVER(ksz8795_netdev_ops);
156 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795, KSZ8795_NAME);
157
158 /*
159 * For Ingress (Host -> KSZ9477), 2/6 bytes are added before FCS.
160 * ---------------------------------------------------------------------------
161 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|tag1(1byte)|
162 * FCS(4bytes)
163 * ---------------------------------------------------------------------------
164 * ts : time stamp (Present only if PTP is enabled in the Hardware)
165 * tag0 : Prioritization (not used now)
166 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
167 *
168 * For Egress (KSZ9477 -> Host), 1/5 bytes is added before FCS.
169 * ---------------------------------------------------------------------------
170 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes)
171 * ---------------------------------------------------------------------------
172 * ts : time stamp (Present only if bit 7 of tag0 is set)
173 * tag0 : zero-based value represents port
174 * (eg, 0x00=port1, 0x02=port3, 0x06=port7)
175 */
176
177 #define KSZ9477_INGRESS_TAG_LEN 2
178 #define KSZ9477_PTP_TAG_LEN 4
179 #define KSZ9477_PTP_TAG_INDICATION 0x80
180
181 #define KSZ9477_TAIL_TAG_PRIO GENMASK(8, 7)
182 #define KSZ9477_TAIL_TAG_OVERRIDE BIT(9)
183 #define KSZ9477_TAIL_TAG_LOOKUP BIT(10)
184
ksz_rcv_timestamp(struct sk_buff * skb,u8 * tag)185 static void ksz_rcv_timestamp(struct sk_buff *skb, u8 *tag)
186 {
187 u8 *tstamp_raw = tag - KSZ_PTP_TAG_LEN;
188 ktime_t tstamp;
189
190 tstamp = ksz_decode_tstamp(get_unaligned_be32(tstamp_raw));
191 KSZ_SKB_CB(skb)->tstamp = tstamp;
192 }
193
194 /* Time stamp tag *needs* to be inserted if PTP is enabled in hardware.
195 * Regardless of Whether it is a PTP frame or not.
196 */
ksz_xmit_timestamp(struct dsa_port * dp,struct sk_buff * skb)197 static void ksz_xmit_timestamp(struct dsa_port *dp, struct sk_buff *skb)
198 {
199 struct ksz_tagger_private *priv;
200 struct ptp_header *ptp_hdr;
201 unsigned int ptp_type;
202 u32 tstamp_raw = 0;
203 s64 correction;
204
205 priv = ksz_tagger_private(dp->ds);
206
207 if (!test_bit(KSZ_HWTS_EN, &priv->state))
208 return;
209
210 if (!KSZ_SKB_CB(skb)->update_correction)
211 goto output_tag;
212
213 ptp_type = KSZ_SKB_CB(skb)->ptp_type;
214
215 ptp_hdr = ptp_parse_header(skb, ptp_type);
216 if (!ptp_hdr)
217 goto output_tag;
218
219 correction = (s64)get_unaligned_be64(&ptp_hdr->correction);
220
221 if (correction < 0) {
222 struct timespec64 ts;
223
224 ts = ns_to_timespec64(-correction >> 16);
225 tstamp_raw = ((ts.tv_sec & 3) << 30) | ts.tv_nsec;
226
227 /* Set correction field to 0 and update UDP checksum */
228 ptp_header_update_correction(skb, ptp_type, ptp_hdr, 0);
229 }
230
231 output_tag:
232 put_unaligned_be32(tstamp_raw, skb_put(skb, KSZ_PTP_TAG_LEN));
233 }
234
235 /* Defer transmit if waiting for egress time stamp is required. */
ksz_defer_xmit(struct dsa_port * dp,struct sk_buff * skb)236 static struct sk_buff *ksz_defer_xmit(struct dsa_port *dp, struct sk_buff *skb)
237 {
238 struct ksz_tagger_data *tagger_data = ksz_tagger_data(dp->ds);
239 struct ksz_tagger_private *priv = ksz_tagger_private(dp->ds);
240 void (*xmit_work_fn)(struct kthread_work *work);
241 struct sk_buff *clone = KSZ_SKB_CB(skb)->clone;
242 struct ksz_deferred_xmit_work *xmit_work;
243 struct kthread_worker *xmit_worker;
244
245 if (!clone)
246 return skb; /* no deferred xmit for this packet */
247
248 xmit_work_fn = tagger_data->xmit_work_fn;
249 xmit_worker = priv->xmit_worker;
250
251 if (!xmit_work_fn || !xmit_worker)
252 return NULL;
253
254 xmit_work = kzalloc(sizeof(*xmit_work), GFP_ATOMIC);
255 if (!xmit_work)
256 return NULL;
257
258 kthread_init_work(&xmit_work->work, xmit_work_fn);
259 /* Increase refcount so the kfree_skb in dsa_slave_xmit
260 * won't really free the packet.
261 */
262 xmit_work->dp = dp;
263 xmit_work->skb = skb_get(skb);
264
265 kthread_queue_work(xmit_worker, &xmit_work->work);
266
267 return NULL;
268 }
269
ksz9477_xmit(struct sk_buff * skb,struct net_device * dev)270 static struct sk_buff *ksz9477_xmit(struct sk_buff *skb,
271 struct net_device *dev)
272 {
273 u16 queue_mapping = skb_get_queue_mapping(skb);
274 u8 prio = netdev_txq_to_tc(dev, queue_mapping);
275 struct dsa_port *dp = dsa_slave_to_port(dev);
276 struct ethhdr *hdr;
277 __be16 *tag;
278 u16 val;
279
280 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
281 return NULL;
282
283 /* Tag encoding */
284 ksz_xmit_timestamp(dp, skb);
285
286 tag = skb_put(skb, KSZ9477_INGRESS_TAG_LEN);
287 hdr = skb_eth_hdr(skb);
288
289 val = BIT(dp->index);
290
291 val |= FIELD_PREP(KSZ9477_TAIL_TAG_PRIO, prio);
292
293 if (is_link_local_ether_addr(hdr->h_dest))
294 val |= KSZ9477_TAIL_TAG_OVERRIDE;
295
296 *tag = cpu_to_be16(val);
297
298 return ksz_defer_xmit(dp, skb);
299 }
300
ksz9477_rcv(struct sk_buff * skb,struct net_device * dev)301 static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev)
302 {
303 /* Tag decoding */
304 u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
305 unsigned int port = tag[0] & 7;
306 unsigned int len = KSZ_EGRESS_TAG_LEN;
307
308 /* Extra 4-bytes PTP timestamp */
309 if (tag[0] & KSZ9477_PTP_TAG_INDICATION) {
310 ksz_rcv_timestamp(skb, tag);
311 len += KSZ_PTP_TAG_LEN;
312 }
313
314 return ksz_common_rcv(skb, dev, port, len);
315 }
316
317 static const struct dsa_device_ops ksz9477_netdev_ops = {
318 .name = KSZ9477_NAME,
319 .proto = DSA_TAG_PROTO_KSZ9477,
320 .xmit = ksz9477_xmit,
321 .rcv = ksz9477_rcv,
322 .connect = ksz_connect,
323 .disconnect = ksz_disconnect,
324 .needed_tailroom = KSZ9477_INGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
325 };
326
327 DSA_TAG_DRIVER(ksz9477_netdev_ops);
328 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9477, KSZ9477_NAME);
329
330 #define KSZ9893_TAIL_TAG_PRIO GENMASK(4, 3)
331 #define KSZ9893_TAIL_TAG_OVERRIDE BIT(5)
332 #define KSZ9893_TAIL_TAG_LOOKUP BIT(6)
333
ksz9893_xmit(struct sk_buff * skb,struct net_device * dev)334 static struct sk_buff *ksz9893_xmit(struct sk_buff *skb,
335 struct net_device *dev)
336 {
337 u16 queue_mapping = skb_get_queue_mapping(skb);
338 u8 prio = netdev_txq_to_tc(dev, queue_mapping);
339 struct dsa_port *dp = dsa_slave_to_port(dev);
340 struct ethhdr *hdr;
341 u8 *tag;
342
343 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
344 return NULL;
345
346 /* Tag encoding */
347 ksz_xmit_timestamp(dp, skb);
348
349 tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);
350 hdr = skb_eth_hdr(skb);
351
352 *tag = BIT(dp->index);
353
354 *tag |= FIELD_PREP(KSZ9893_TAIL_TAG_PRIO, prio);
355
356 if (is_link_local_ether_addr(hdr->h_dest))
357 *tag |= KSZ9893_TAIL_TAG_OVERRIDE;
358
359 return ksz_defer_xmit(dp, skb);
360 }
361
362 static const struct dsa_device_ops ksz9893_netdev_ops = {
363 .name = KSZ9893_NAME,
364 .proto = DSA_TAG_PROTO_KSZ9893,
365 .xmit = ksz9893_xmit,
366 .rcv = ksz9477_rcv,
367 .connect = ksz_connect,
368 .disconnect = ksz_disconnect,
369 .needed_tailroom = KSZ_INGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
370 };
371
372 DSA_TAG_DRIVER(ksz9893_netdev_ops);
373 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893, KSZ9893_NAME);
374
375 /* For xmit, 2/6 bytes are added before FCS.
376 * ---------------------------------------------------------------------------
377 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|tag1(1byte)|
378 * FCS(4bytes)
379 * ---------------------------------------------------------------------------
380 * ts : time stamp (Present only if PTP is enabled in the Hardware)
381 * tag0 : represents tag override, lookup and valid
382 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x80=port8)
383 *
384 * For rcv, 1/5 bytes is added before FCS.
385 * ---------------------------------------------------------------------------
386 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes)
387 * ---------------------------------------------------------------------------
388 * ts : time stamp (Present only if bit 7 of tag0 is set)
389 * tag0 : zero-based value represents port
390 * (eg, 0x00=port1, 0x02=port3, 0x07=port8)
391 */
392 #define LAN937X_EGRESS_TAG_LEN 2
393
394 #define LAN937X_TAIL_TAG_BLOCKING_OVERRIDE BIT(11)
395 #define LAN937X_TAIL_TAG_LOOKUP BIT(12)
396 #define LAN937X_TAIL_TAG_VALID BIT(13)
397 #define LAN937X_TAIL_TAG_PRIO GENMASK(10, 8)
398 #define LAN937X_TAIL_TAG_PORT_MASK 7
399
lan937x_xmit(struct sk_buff * skb,struct net_device * dev)400 static struct sk_buff *lan937x_xmit(struct sk_buff *skb,
401 struct net_device *dev)
402 {
403 u16 queue_mapping = skb_get_queue_mapping(skb);
404 u8 prio = netdev_txq_to_tc(dev, queue_mapping);
405 struct dsa_port *dp = dsa_slave_to_port(dev);
406 const struct ethhdr *hdr = eth_hdr(skb);
407 __be16 *tag;
408 u16 val;
409
410 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
411 return NULL;
412
413 ksz_xmit_timestamp(dp, skb);
414
415 tag = skb_put(skb, LAN937X_EGRESS_TAG_LEN);
416
417 val = BIT(dp->index);
418
419 val |= FIELD_PREP(LAN937X_TAIL_TAG_PRIO, prio);
420
421 if (is_link_local_ether_addr(hdr->h_dest))
422 val |= LAN937X_TAIL_TAG_BLOCKING_OVERRIDE;
423
424 /* Tail tag valid bit - This bit should always be set by the CPU */
425 val |= LAN937X_TAIL_TAG_VALID;
426
427 put_unaligned_be16(val, tag);
428
429 return ksz_defer_xmit(dp, skb);
430 }
431
432 static const struct dsa_device_ops lan937x_netdev_ops = {
433 .name = LAN937X_NAME,
434 .proto = DSA_TAG_PROTO_LAN937X,
435 .xmit = lan937x_xmit,
436 .rcv = ksz9477_rcv,
437 .connect = ksz_connect,
438 .disconnect = ksz_disconnect,
439 .needed_tailroom = LAN937X_EGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
440 };
441
442 DSA_TAG_DRIVER(lan937x_netdev_ops);
443 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_LAN937X, LAN937X_NAME);
444
445 static struct dsa_tag_driver *dsa_tag_driver_array[] = {
446 &DSA_TAG_DRIVER_NAME(ksz8795_netdev_ops),
447 &DSA_TAG_DRIVER_NAME(ksz9477_netdev_ops),
448 &DSA_TAG_DRIVER_NAME(ksz9893_netdev_ops),
449 &DSA_TAG_DRIVER_NAME(lan937x_netdev_ops),
450 };
451
452 module_dsa_tag_drivers(dsa_tag_driver_array);
453
454 MODULE_LICENSE("GPL");
455
