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 KSZ8463_NAME "ksz8463"
16 #define KSZ8795_NAME "ksz8795"
17 #define KSZ9477_NAME "ksz9477"
18 #define KSZ9893_NAME "ksz9893"
19 #define LAN937X_NAME "lan937x"
20
21 /* Typically only one byte is used for tail tag. */
22 #define KSZ_PTP_TAG_LEN 4
23 #define KSZ_EGRESS_TAG_LEN 1
24 #define KSZ_INGRESS_TAG_LEN 1
25
26 #define KSZ_HWTS_EN 0
27
28 struct ksz_tagger_private {
29 struct ksz_tagger_data data; /* Must be first */
30 unsigned long state;
31 struct kthread_worker *xmit_worker;
32 };
33
34 static struct ksz_tagger_private *
ksz_tagger_private(struct dsa_switch * ds)35 ksz_tagger_private(struct dsa_switch *ds)
36 {
37 return ds->tagger_data;
38 }
39
ksz_hwtstamp_set_state(struct dsa_switch * ds,bool on)40 static void ksz_hwtstamp_set_state(struct dsa_switch *ds, bool on)
41 {
42 struct ksz_tagger_private *priv = ksz_tagger_private(ds);
43
44 if (on)
45 set_bit(KSZ_HWTS_EN, &priv->state);
46 else
47 clear_bit(KSZ_HWTS_EN, &priv->state);
48 }
49
ksz_disconnect(struct dsa_switch * ds)50 static void ksz_disconnect(struct dsa_switch *ds)
51 {
52 struct ksz_tagger_private *priv = ds->tagger_data;
53
54 kthread_destroy_worker(priv->xmit_worker);
55 kfree(priv);
56 ds->tagger_data = NULL;
57 }
58
ksz_connect(struct dsa_switch * ds)59 static int ksz_connect(struct dsa_switch *ds)
60 {
61 struct ksz_tagger_data *tagger_data;
62 struct kthread_worker *xmit_worker;
63 struct ksz_tagger_private *priv;
64 int ret;
65
66 priv = kzalloc_obj(*priv);
67 if (!priv)
68 return -ENOMEM;
69
70 xmit_worker = kthread_run_worker(0, "dsa%d:%d_xmit",
71 ds->dst->index, ds->index);
72 if (IS_ERR(xmit_worker)) {
73 ret = PTR_ERR(xmit_worker);
74 kfree(priv);
75 return ret;
76 }
77
78 priv->xmit_worker = xmit_worker;
79 /* Export functions for switch driver use */
80 tagger_data = &priv->data;
81 tagger_data->hwtstamp_set_state = ksz_hwtstamp_set_state;
82 ds->tagger_data = priv;
83
84 return 0;
85 }
86
ksz_common_rcv(struct sk_buff * skb,struct net_device * dev,unsigned int port,unsigned int len)87 static struct sk_buff *ksz_common_rcv(struct sk_buff *skb,
88 struct net_device *dev,
89 unsigned int port, unsigned int len)
90 {
91 skb->dev = dsa_conduit_find_user(dev, 0, port);
92 if (!skb->dev) {
93 kfree_skb(skb);
94 return NULL;
95 }
96
97 if (pskb_trim_rcsum(skb, skb->len - len)) {
98 kfree_skb(skb);
99 return NULL;
100 }
101
102 dsa_default_offload_fwd_mark(skb);
103
104 return skb;
105 }
106
107 /*
108 * For Ingress (Host -> KSZ9477), 2/6 bytes are added before FCS.
109 * ---------------------------------------------------------------------------
110 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|tag1(1byte)|
111 * FCS(4bytes)
112 * ---------------------------------------------------------------------------
113 * ts : time stamp (Present only if PTP is enabled in the Hardware)
114 * tag0 : Prioritization (not used now)
115 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
116 *
117 * For Egress (KSZ9477 -> Host), 1/5 bytes is added before FCS.
118 * ---------------------------------------------------------------------------
119 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes)
120 * ---------------------------------------------------------------------------
121 * ts : time stamp (Present only if bit 7 of tag0 is set)
122 * tag0 : zero-based value represents port
123 * (eg, 0x00=port1, 0x02=port3, 0x06=port7)
124 */
125
126 #define KSZ9477_INGRESS_TAG_LEN 2
127 #define KSZ9477_PTP_TAG_LEN 4
128 #define KSZ9477_PTP_TAG_INDICATION BIT(7)
129
130 #define KSZ9477_TAIL_TAG_EG_PORT_M GENMASK(2, 0)
131 #define KSZ9477_TAIL_TAG_PRIO GENMASK(8, 7)
132 #define KSZ9477_TAIL_TAG_OVERRIDE BIT(9)
133 #define KSZ9477_TAIL_TAG_LOOKUP BIT(10)
134
ksz_rcv_timestamp(struct sk_buff * skb,u8 * tag)135 static void ksz_rcv_timestamp(struct sk_buff *skb, u8 *tag)
136 {
137 u8 *tstamp_raw = tag - KSZ_PTP_TAG_LEN;
138 ktime_t tstamp;
139
140 tstamp = ksz_decode_tstamp(get_unaligned_be32(tstamp_raw));
141 KSZ_SKB_CB(skb)->tstamp = tstamp;
142 }
143
144 /* Time stamp tag *needs* to be inserted if PTP is enabled in hardware.
145 * Regardless of Whether it is a PTP frame or not.
146 */
ksz_xmit_timestamp(struct dsa_port * dp,struct sk_buff * skb)147 static void ksz_xmit_timestamp(struct dsa_port *dp, struct sk_buff *skb)
148 {
149 struct ksz_tagger_private *priv;
150 struct ptp_header *ptp_hdr;
151 unsigned int ptp_type;
152 u32 tstamp_raw = 0;
153 s64 correction;
154
155 priv = ksz_tagger_private(dp->ds);
156
157 if (!test_bit(KSZ_HWTS_EN, &priv->state))
158 return;
159
160 if (!KSZ_SKB_CB(skb)->update_correction)
161 goto output_tag;
162
163 ptp_type = KSZ_SKB_CB(skb)->ptp_type;
164
165 ptp_hdr = ptp_parse_header(skb, ptp_type);
166 if (!ptp_hdr)
167 goto output_tag;
168
169 correction = (s64)get_unaligned_be64(&ptp_hdr->correction);
170
171 if (correction < 0) {
172 struct timespec64 ts;
173
174 ts = ns_to_timespec64(-correction >> 16);
175 tstamp_raw = ((ts.tv_sec & 3) << 30) | ts.tv_nsec;
176
177 /* Set correction field to 0 and update UDP checksum */
178 ptp_header_update_correction(skb, ptp_type, ptp_hdr, 0);
179 }
180
181 output_tag:
182 put_unaligned_be32(tstamp_raw, skb_put(skb, KSZ_PTP_TAG_LEN));
183 }
184
185 /* Defer transmit if waiting for egress time stamp is required. */
ksz_defer_xmit(struct dsa_port * dp,struct sk_buff * skb)186 static struct sk_buff *ksz_defer_xmit(struct dsa_port *dp, struct sk_buff *skb)
187 {
188 struct ksz_tagger_data *tagger_data = ksz_tagger_data(dp->ds);
189 struct ksz_tagger_private *priv = ksz_tagger_private(dp->ds);
190 void (*xmit_work_fn)(struct kthread_work *work);
191 struct sk_buff *clone = KSZ_SKB_CB(skb)->clone;
192 struct ksz_deferred_xmit_work *xmit_work;
193 struct kthread_worker *xmit_worker;
194
195 if (!clone)
196 return skb; /* no deferred xmit for this packet */
197
198 xmit_work_fn = tagger_data->xmit_work_fn;
199 xmit_worker = priv->xmit_worker;
200
201 if (!xmit_work_fn || !xmit_worker) {
202 kfree_skb(skb);
203 return NULL;
204 }
205
206 xmit_work = kzalloc_obj(*xmit_work, GFP_ATOMIC);
207 if (!xmit_work) {
208 kfree_skb(skb);
209 return NULL;
210 }
211
212 kthread_init_work(&xmit_work->work, xmit_work_fn);
213 xmit_work->dp = dp;
214 xmit_work->skb = skb_get(skb);
215
216 kthread_queue_work(xmit_worker, &xmit_work->work);
217
218 kfree_skb(skb);
219 return NULL;
220 }
221
ksz_common_xmit(struct sk_buff * skb,struct net_device * dev,bool do_tstamp,u8 prio,u8 override_mask)222 static struct sk_buff *ksz_common_xmit(struct sk_buff *skb,
223 struct net_device *dev,
224 bool do_tstamp,
225 u8 prio,
226 u8 override_mask)
227 {
228 struct dsa_port *dp = dsa_user_to_port(dev);
229 struct ethhdr *hdr;
230 u8 *tag;
231
232 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) {
233 kfree_skb(skb);
234 return NULL;
235 }
236
237 /* Tag encoding */
238 if (do_tstamp)
239 ksz_xmit_timestamp(dp, skb);
240
241 tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);
242 hdr = skb_eth_hdr(skb);
243
244 *tag = dsa_xmit_port_mask(skb, dev);
245 *tag |= prio;
246
247 if (is_link_local_ether_addr(hdr->h_dest))
248 *tag |= override_mask;
249
250 return ksz_defer_xmit(dp, skb);
251 }
252
ksz9477_xmit(struct sk_buff * skb,struct net_device * dev)253 static struct sk_buff *ksz9477_xmit(struct sk_buff *skb,
254 struct net_device *dev)
255 {
256 u16 queue_mapping = skb_get_queue_mapping(skb);
257 u8 prio = netdev_txq_to_tc(dev, queue_mapping);
258 struct dsa_port *dp = dsa_user_to_port(dev);
259 struct ethhdr *hdr;
260 __be16 *tag;
261 u16 val;
262
263 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) {
264 kfree_skb(skb);
265 return NULL;
266 }
267
268 /* Tag encoding */
269 ksz_xmit_timestamp(dp, skb);
270
271 tag = skb_put(skb, KSZ9477_INGRESS_TAG_LEN);
272 hdr = skb_eth_hdr(skb);
273
274 val = dsa_xmit_port_mask(skb, dev);
275 val |= FIELD_PREP(KSZ9477_TAIL_TAG_PRIO, prio);
276
277 if (is_link_local_ether_addr(hdr->h_dest))
278 val |= KSZ9477_TAIL_TAG_OVERRIDE;
279
280 *tag = cpu_to_be16(val);
281
282 return ksz_defer_xmit(dp, skb);
283 }
284
ksz9477_rcv(struct sk_buff * skb,struct net_device * dev)285 static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev)
286 {
287 unsigned int len = KSZ_EGRESS_TAG_LEN;
288 unsigned int port;
289 u8 *tag;
290
291 if (skb_linearize(skb)) {
292 kfree_skb(skb);
293 return NULL;
294 }
295
296 /* Tag decoding */
297 tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
298 port = tag[0] & KSZ9477_TAIL_TAG_EG_PORT_M;
299
300 /* Extra 4-bytes PTP timestamp */
301 if (tag[0] & KSZ9477_PTP_TAG_INDICATION) {
302 ksz_rcv_timestamp(skb, tag);
303 len += KSZ_PTP_TAG_LEN;
304 }
305
306 return ksz_common_rcv(skb, dev, port, len);
307 }
308
309 static const struct dsa_device_ops ksz9477_netdev_ops = {
310 .name = KSZ9477_NAME,
311 .proto = DSA_TAG_PROTO_KSZ9477,
312 .xmit = ksz9477_xmit,
313 .rcv = ksz9477_rcv,
314 .connect = ksz_connect,
315 .disconnect = ksz_disconnect,
316 .needed_tailroom = KSZ9477_INGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
317 };
318
319 DSA_TAG_DRIVER(ksz9477_netdev_ops);
320 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9477, KSZ9477_NAME);
321
322 /*
323 * For Ingress (Host -> KSZ8795), 1 byte is added before FCS.
324 * ---------------------------------------------------------------------------
325 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag(1byte)|FCS(4bytes)
326 * ---------------------------------------------------------------------------
327 * tag : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
328 *
329 * For Egress (KSZ8795 -> Host), 1 byte is added before FCS.
330 * ---------------------------------------------------------------------------
331 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
332 * ---------------------------------------------------------------------------
333 * tag0 : zero-based value represents port
334 * (eg, 0x0=port1, 0x2=port3, 0x3=port4)
335 */
336
337 #define KSZ8795_TAIL_TAG_EG_PORT_M GENMASK(1, 0)
338 #define KSZ8795_TAIL_TAG_OVERRIDE BIT(6)
339 #define KSZ8795_TAIL_TAG_LOOKUP BIT(7)
340
ksz8795_xmit(struct sk_buff * skb,struct net_device * dev)341 static struct sk_buff *ksz8795_xmit(struct sk_buff *skb, struct net_device *dev)
342 {
343 return ksz_common_xmit(skb, dev, false, 0, KSZ8795_TAIL_TAG_OVERRIDE);
344 }
345
ksz8795_rcv(struct sk_buff * skb,struct net_device * dev)346 static struct sk_buff *ksz8795_rcv(struct sk_buff *skb, struct net_device *dev)
347 {
348 u8 *tag;
349
350 if (skb_linearize(skb)) {
351 kfree_skb(skb);
352 return NULL;
353 }
354
355 tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
356
357 return ksz_common_rcv(skb, dev, tag[0] & KSZ8795_TAIL_TAG_EG_PORT_M,
358 KSZ_EGRESS_TAG_LEN);
359 }
360
361 static const struct dsa_device_ops ksz8795_netdev_ops = {
362 .name = KSZ8795_NAME,
363 .proto = DSA_TAG_PROTO_KSZ8795,
364 .xmit = ksz8795_xmit,
365 .rcv = ksz8795_rcv,
366 .needed_tailroom = KSZ_INGRESS_TAG_LEN,
367 };
368
369 DSA_TAG_DRIVER(ksz8795_netdev_ops);
370 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795, KSZ8795_NAME);
371
372 #define KSZ9893_TAIL_TAG_PRIO GENMASK(4, 3)
373 #define KSZ9893_TAIL_TAG_OVERRIDE BIT(5)
374 #define KSZ9893_TAIL_TAG_LOOKUP BIT(6)
375
ksz9893_xmit(struct sk_buff * skb,struct net_device * dev)376 static struct sk_buff *ksz9893_xmit(struct sk_buff *skb,
377 struct net_device *dev)
378 {
379 u16 queue_mapping = skb_get_queue_mapping(skb);
380 u8 prio = netdev_txq_to_tc(dev, queue_mapping);
381
382 return ksz_common_xmit(skb, dev, true,
383 FIELD_PREP(KSZ9893_TAIL_TAG_PRIO, prio),
384 KSZ9893_TAIL_TAG_OVERRIDE);
385 }
386
387 static const struct dsa_device_ops ksz9893_netdev_ops = {
388 .name = KSZ9893_NAME,
389 .proto = DSA_TAG_PROTO_KSZ9893,
390 .xmit = ksz9893_xmit,
391 .rcv = ksz9477_rcv,
392 .connect = ksz_connect,
393 .disconnect = ksz_disconnect,
394 .needed_tailroom = KSZ_INGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
395 };
396
397 DSA_TAG_DRIVER(ksz9893_netdev_ops);
398 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893, KSZ9893_NAME);
399
400 #define KSZ8463_TAIL_TAG_PRIO GENMASK(4, 3)
401 #define KSZ8463_TAIL_TAG_EG_PORT_M GENMASK(2, 0)
402
ksz8463_xmit(struct sk_buff * skb,struct net_device * dev)403 static struct sk_buff *ksz8463_xmit(struct sk_buff *skb,
404 struct net_device *dev)
405 {
406 u16 queue_mapping = skb_get_queue_mapping(skb);
407 u8 prio = netdev_txq_to_tc(dev, queue_mapping);
408
409 return ksz_common_xmit(skb, dev, false,
410 FIELD_PREP(KSZ8463_TAIL_TAG_PRIO, prio),
411 0);
412 }
413
ksz8463_rcv(struct sk_buff * skb,struct net_device * dev)414 static struct sk_buff *ksz8463_rcv(struct sk_buff *skb, struct net_device *dev)
415 {
416 unsigned int len = KSZ_EGRESS_TAG_LEN;
417 struct ptp_header *ptp_hdr;
418 unsigned int ptp_class;
419 unsigned int port;
420 ktime_t ts;
421 u8 *tag;
422
423 if (skb_linearize(skb)) {
424 kfree_skb(skb);
425 return NULL;
426 }
427
428 KSZ_SKB_CB(skb)->tstamp = 0;
429
430 /* Tag decoding */
431 tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
432 port = tag[0] & KSZ8463_TAIL_TAG_EG_PORT_M;
433
434 __skb_push(skb, ETH_HLEN);
435 ptp_class = ptp_classify_raw(skb);
436 __skb_pull(skb, ETH_HLEN);
437 if (ptp_class == PTP_CLASS_NONE)
438 goto common_rcv;
439
440 ptp_hdr = ptp_parse_header(skb, ptp_class);
441 if (ptp_hdr) {
442 ts = ksz_decode_tstamp(get_unaligned_be32(&ptp_hdr->reserved2));
443 KSZ_SKB_CB(skb)->tstamp = ts;
444 ptp_hdr->reserved2 = 0;
445 }
446
447 common_rcv:
448 return ksz_common_rcv(skb, dev, port, len);
449 }
450
451 static const struct dsa_device_ops ksz8463_netdev_ops = {
452 .name = KSZ8463_NAME,
453 .proto = DSA_TAG_PROTO_KSZ8463,
454 .xmit = ksz8463_xmit,
455 .rcv = ksz8463_rcv,
456 .connect = ksz_connect,
457 .disconnect = ksz_disconnect,
458 .needed_tailroom = KSZ_INGRESS_TAG_LEN,
459 };
460
461 DSA_TAG_DRIVER(ksz8463_netdev_ops);
462 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8463, KSZ8463_NAME);
463
464 /* For xmit, 2/6 bytes are added before FCS.
465 * ---------------------------------------------------------------------------
466 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|tag1(1byte)|
467 * FCS(4bytes)
468 * ---------------------------------------------------------------------------
469 * ts : time stamp (Present only if PTP is enabled in the Hardware)
470 * tag0 : represents tag override, lookup and valid
471 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x80=port8)
472 *
473 * For rcv, 1/5 bytes is added before FCS.
474 * ---------------------------------------------------------------------------
475 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes)
476 * ---------------------------------------------------------------------------
477 * ts : time stamp (Present only if bit 7 of tag0 is set)
478 * tag0 : zero-based value represents port
479 * (eg, 0x00=port1, 0x02=port3, 0x07=port8)
480 */
481 #define LAN937X_EGRESS_TAG_LEN 2
482
483 #define LAN937X_TAIL_TAG_BLOCKING_OVERRIDE BIT(11)
484 #define LAN937X_TAIL_TAG_LOOKUP BIT(12)
485 #define LAN937X_TAIL_TAG_VALID BIT(13)
486 #define LAN937X_TAIL_TAG_PRIO GENMASK(10, 8)
487 #define LAN937X_TAIL_TAG_PORT_MASK 7
488
lan937x_xmit(struct sk_buff * skb,struct net_device * dev)489 static struct sk_buff *lan937x_xmit(struct sk_buff *skb,
490 struct net_device *dev)
491 {
492 u16 queue_mapping = skb_get_queue_mapping(skb);
493 u8 prio = netdev_txq_to_tc(dev, queue_mapping);
494 struct dsa_port *dp = dsa_user_to_port(dev);
495 const struct ethhdr *hdr = eth_hdr(skb);
496 __be16 *tag;
497 u16 val;
498
499 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb)) {
500 kfree_skb(skb);
501 return NULL;
502 }
503
504 ksz_xmit_timestamp(dp, skb);
505
506 tag = skb_put(skb, LAN937X_EGRESS_TAG_LEN);
507
508 val = dsa_xmit_port_mask(skb, dev);
509 val |= FIELD_PREP(LAN937X_TAIL_TAG_PRIO, prio);
510
511 if (is_link_local_ether_addr(hdr->h_dest))
512 val |= LAN937X_TAIL_TAG_BLOCKING_OVERRIDE;
513
514 /* Tail tag valid bit - This bit should always be set by the CPU */
515 val |= LAN937X_TAIL_TAG_VALID;
516
517 put_unaligned_be16(val, tag);
518
519 return ksz_defer_xmit(dp, skb);
520 }
521
522 static const struct dsa_device_ops lan937x_netdev_ops = {
523 .name = LAN937X_NAME,
524 .proto = DSA_TAG_PROTO_LAN937X,
525 .xmit = lan937x_xmit,
526 .rcv = ksz9477_rcv,
527 .connect = ksz_connect,
528 .disconnect = ksz_disconnect,
529 .needed_tailroom = LAN937X_EGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
530 };
531
532 DSA_TAG_DRIVER(lan937x_netdev_ops);
533 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_LAN937X, LAN937X_NAME);
534
535 static struct dsa_tag_driver *dsa_tag_driver_array[] = {
536 &DSA_TAG_DRIVER_NAME(ksz8463_netdev_ops),
537 &DSA_TAG_DRIVER_NAME(ksz8795_netdev_ops),
538 &DSA_TAG_DRIVER_NAME(ksz9477_netdev_ops),
539 &DSA_TAG_DRIVER_NAME(ksz9893_netdev_ops),
540 &DSA_TAG_DRIVER_NAME(lan937x_netdev_ops),
541 };
542
543 module_dsa_tag_drivers(dsa_tag_driver_array);
544
545 MODULE_DESCRIPTION("DSA tag driver for Microchip 8795/937x/9477/9893 families of switches");
546 MODULE_LICENSE("GPL");
547