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_obj(*priv);
66 if (!priv)
67 return -ENOMEM;
68
69 xmit_worker = kthread_run_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_conduit_find_user(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, 0x0=port1, 0x2=port3, 0x3=port4)
115 */
116
117 #define KSZ8795_TAIL_TAG_EG_PORT_M GENMASK(1, 0)
118 #define KSZ8795_TAIL_TAG_OVERRIDE BIT(6)
119 #define KSZ8795_TAIL_TAG_LOOKUP BIT(7)
120
ksz8795_xmit(struct sk_buff * skb,struct net_device * dev)121 static struct sk_buff *ksz8795_xmit(struct sk_buff *skb, struct net_device *dev)
122 {
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 = dsa_xmit_port_mask(skb, dev);
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;
143
144 if (skb_linearize(skb))
145 return NULL;
146
147 tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
148
149 return ksz_common_rcv(skb, dev, tag[0] & KSZ8795_TAIL_TAG_EG_PORT_M,
150 KSZ_EGRESS_TAG_LEN);
151 }
152
153 static const struct dsa_device_ops ksz8795_netdev_ops = {
154 .name = KSZ8795_NAME,
155 .proto = DSA_TAG_PROTO_KSZ8795,
156 .xmit = ksz8795_xmit,
157 .rcv = ksz8795_rcv,
158 .needed_tailroom = KSZ_INGRESS_TAG_LEN,
159 };
160
161 DSA_TAG_DRIVER(ksz8795_netdev_ops);
162 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795, KSZ8795_NAME);
163
164 /*
165 * For Ingress (Host -> KSZ9477), 2/6 bytes are added before FCS.
166 * ---------------------------------------------------------------------------
167 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|tag1(1byte)|
168 * FCS(4bytes)
169 * ---------------------------------------------------------------------------
170 * ts : time stamp (Present only if PTP is enabled in the Hardware)
171 * tag0 : Prioritization (not used now)
172 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
173 *
174 * For Egress (KSZ9477 -> Host), 1/5 bytes is added before FCS.
175 * ---------------------------------------------------------------------------
176 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes)
177 * ---------------------------------------------------------------------------
178 * ts : time stamp (Present only if bit 7 of tag0 is set)
179 * tag0 : zero-based value represents port
180 * (eg, 0x00=port1, 0x02=port3, 0x06=port7)
181 */
182
183 #define KSZ9477_INGRESS_TAG_LEN 2
184 #define KSZ9477_PTP_TAG_LEN 4
185 #define KSZ9477_PTP_TAG_INDICATION BIT(7)
186
187 #define KSZ9477_TAIL_TAG_EG_PORT_M GENMASK(2, 0)
188 #define KSZ9477_TAIL_TAG_PRIO GENMASK(8, 7)
189 #define KSZ9477_TAIL_TAG_OVERRIDE BIT(9)
190 #define KSZ9477_TAIL_TAG_LOOKUP BIT(10)
191
ksz_rcv_timestamp(struct sk_buff * skb,u8 * tag)192 static void ksz_rcv_timestamp(struct sk_buff *skb, u8 *tag)
193 {
194 u8 *tstamp_raw = tag - KSZ_PTP_TAG_LEN;
195 ktime_t tstamp;
196
197 tstamp = ksz_decode_tstamp(get_unaligned_be32(tstamp_raw));
198 KSZ_SKB_CB(skb)->tstamp = tstamp;
199 }
200
201 /* Time stamp tag *needs* to be inserted if PTP is enabled in hardware.
202 * Regardless of Whether it is a PTP frame or not.
203 */
ksz_xmit_timestamp(struct dsa_port * dp,struct sk_buff * skb)204 static void ksz_xmit_timestamp(struct dsa_port *dp, struct sk_buff *skb)
205 {
206 struct ksz_tagger_private *priv;
207 struct ptp_header *ptp_hdr;
208 unsigned int ptp_type;
209 u32 tstamp_raw = 0;
210 s64 correction;
211
212 priv = ksz_tagger_private(dp->ds);
213
214 if (!test_bit(KSZ_HWTS_EN, &priv->state))
215 return;
216
217 if (!KSZ_SKB_CB(skb)->update_correction)
218 goto output_tag;
219
220 ptp_type = KSZ_SKB_CB(skb)->ptp_type;
221
222 ptp_hdr = ptp_parse_header(skb, ptp_type);
223 if (!ptp_hdr)
224 goto output_tag;
225
226 correction = (s64)get_unaligned_be64(&ptp_hdr->correction);
227
228 if (correction < 0) {
229 struct timespec64 ts;
230
231 ts = ns_to_timespec64(-correction >> 16);
232 tstamp_raw = ((ts.tv_sec & 3) << 30) | ts.tv_nsec;
233
234 /* Set correction field to 0 and update UDP checksum */
235 ptp_header_update_correction(skb, ptp_type, ptp_hdr, 0);
236 }
237
238 output_tag:
239 put_unaligned_be32(tstamp_raw, skb_put(skb, KSZ_PTP_TAG_LEN));
240 }
241
242 /* Defer transmit if waiting for egress time stamp is required. */
ksz_defer_xmit(struct dsa_port * dp,struct sk_buff * skb)243 static struct sk_buff *ksz_defer_xmit(struct dsa_port *dp, struct sk_buff *skb)
244 {
245 struct ksz_tagger_data *tagger_data = ksz_tagger_data(dp->ds);
246 struct ksz_tagger_private *priv = ksz_tagger_private(dp->ds);
247 void (*xmit_work_fn)(struct kthread_work *work);
248 struct sk_buff *clone = KSZ_SKB_CB(skb)->clone;
249 struct ksz_deferred_xmit_work *xmit_work;
250 struct kthread_worker *xmit_worker;
251
252 if (!clone)
253 return skb; /* no deferred xmit for this packet */
254
255 xmit_work_fn = tagger_data->xmit_work_fn;
256 xmit_worker = priv->xmit_worker;
257
258 if (!xmit_work_fn || !xmit_worker)
259 return NULL;
260
261 xmit_work = kzalloc_obj(*xmit_work, GFP_ATOMIC);
262 if (!xmit_work)
263 return NULL;
264
265 kthread_init_work(&xmit_work->work, xmit_work_fn);
266 /* Increase refcount so the kfree_skb in dsa_user_xmit
267 * won't really free the packet.
268 */
269 xmit_work->dp = dp;
270 xmit_work->skb = skb_get(skb);
271
272 kthread_queue_work(xmit_worker, &xmit_work->work);
273
274 return NULL;
275 }
276
ksz9477_xmit(struct sk_buff * skb,struct net_device * dev)277 static struct sk_buff *ksz9477_xmit(struct sk_buff *skb,
278 struct net_device *dev)
279 {
280 u16 queue_mapping = skb_get_queue_mapping(skb);
281 u8 prio = netdev_txq_to_tc(dev, queue_mapping);
282 struct dsa_port *dp = dsa_user_to_port(dev);
283 struct ethhdr *hdr;
284 __be16 *tag;
285 u16 val;
286
287 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
288 return NULL;
289
290 /* Tag encoding */
291 ksz_xmit_timestamp(dp, skb);
292
293 tag = skb_put(skb, KSZ9477_INGRESS_TAG_LEN);
294 hdr = skb_eth_hdr(skb);
295
296 val = dsa_xmit_port_mask(skb, dev);
297 val |= FIELD_PREP(KSZ9477_TAIL_TAG_PRIO, prio);
298
299 if (is_link_local_ether_addr(hdr->h_dest))
300 val |= KSZ9477_TAIL_TAG_OVERRIDE;
301
302 *tag = cpu_to_be16(val);
303
304 return ksz_defer_xmit(dp, skb);
305 }
306
ksz9477_rcv(struct sk_buff * skb,struct net_device * dev)307 static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev)
308 {
309 unsigned int len = KSZ_EGRESS_TAG_LEN;
310 unsigned int port;
311 u8 *tag;
312
313 if (skb_linearize(skb))
314 return NULL;
315
316 /* Tag decoding */
317 tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
318 port = tag[0] & KSZ9477_TAIL_TAG_EG_PORT_M;
319
320 /* Extra 4-bytes PTP timestamp */
321 if (tag[0] & KSZ9477_PTP_TAG_INDICATION) {
322 ksz_rcv_timestamp(skb, tag);
323 len += KSZ_PTP_TAG_LEN;
324 }
325
326 return ksz_common_rcv(skb, dev, port, len);
327 }
328
329 static const struct dsa_device_ops ksz9477_netdev_ops = {
330 .name = KSZ9477_NAME,
331 .proto = DSA_TAG_PROTO_KSZ9477,
332 .xmit = ksz9477_xmit,
333 .rcv = ksz9477_rcv,
334 .connect = ksz_connect,
335 .disconnect = ksz_disconnect,
336 .needed_tailroom = KSZ9477_INGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
337 };
338
339 DSA_TAG_DRIVER(ksz9477_netdev_ops);
340 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9477, KSZ9477_NAME);
341
342 #define KSZ9893_TAIL_TAG_PRIO GENMASK(4, 3)
343 #define KSZ9893_TAIL_TAG_OVERRIDE BIT(5)
344 #define KSZ9893_TAIL_TAG_LOOKUP BIT(6)
345
ksz9893_xmit(struct sk_buff * skb,struct net_device * dev)346 static struct sk_buff *ksz9893_xmit(struct sk_buff *skb,
347 struct net_device *dev)
348 {
349 u16 queue_mapping = skb_get_queue_mapping(skb);
350 u8 prio = netdev_txq_to_tc(dev, queue_mapping);
351 struct dsa_port *dp = dsa_user_to_port(dev);
352 struct ethhdr *hdr;
353 u8 *tag;
354
355 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
356 return NULL;
357
358 /* Tag encoding */
359 ksz_xmit_timestamp(dp, skb);
360
361 tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);
362 hdr = skb_eth_hdr(skb);
363
364 *tag = dsa_xmit_port_mask(skb, dev);
365 *tag |= FIELD_PREP(KSZ9893_TAIL_TAG_PRIO, prio);
366
367 if (is_link_local_ether_addr(hdr->h_dest))
368 *tag |= KSZ9893_TAIL_TAG_OVERRIDE;
369
370 return ksz_defer_xmit(dp, skb);
371 }
372
373 static const struct dsa_device_ops ksz9893_netdev_ops = {
374 .name = KSZ9893_NAME,
375 .proto = DSA_TAG_PROTO_KSZ9893,
376 .xmit = ksz9893_xmit,
377 .rcv = ksz9477_rcv,
378 .connect = ksz_connect,
379 .disconnect = ksz_disconnect,
380 .needed_tailroom = KSZ_INGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
381 };
382
383 DSA_TAG_DRIVER(ksz9893_netdev_ops);
384 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893, KSZ9893_NAME);
385
386 /* For xmit, 2/6 bytes are added before FCS.
387 * ---------------------------------------------------------------------------
388 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|tag1(1byte)|
389 * FCS(4bytes)
390 * ---------------------------------------------------------------------------
391 * ts : time stamp (Present only if PTP is enabled in the Hardware)
392 * tag0 : represents tag override, lookup and valid
393 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x80=port8)
394 *
395 * For rcv, 1/5 bytes is added before FCS.
396 * ---------------------------------------------------------------------------
397 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes)
398 * ---------------------------------------------------------------------------
399 * ts : time stamp (Present only if bit 7 of tag0 is set)
400 * tag0 : zero-based value represents port
401 * (eg, 0x00=port1, 0x02=port3, 0x07=port8)
402 */
403 #define LAN937X_EGRESS_TAG_LEN 2
404
405 #define LAN937X_TAIL_TAG_BLOCKING_OVERRIDE BIT(11)
406 #define LAN937X_TAIL_TAG_LOOKUP BIT(12)
407 #define LAN937X_TAIL_TAG_VALID BIT(13)
408 #define LAN937X_TAIL_TAG_PRIO GENMASK(10, 8)
409 #define LAN937X_TAIL_TAG_PORT_MASK 7
410
lan937x_xmit(struct sk_buff * skb,struct net_device * dev)411 static struct sk_buff *lan937x_xmit(struct sk_buff *skb,
412 struct net_device *dev)
413 {
414 u16 queue_mapping = skb_get_queue_mapping(skb);
415 u8 prio = netdev_txq_to_tc(dev, queue_mapping);
416 struct dsa_port *dp = dsa_user_to_port(dev);
417 const struct ethhdr *hdr = eth_hdr(skb);
418 __be16 *tag;
419 u16 val;
420
421 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
422 return NULL;
423
424 ksz_xmit_timestamp(dp, skb);
425
426 tag = skb_put(skb, LAN937X_EGRESS_TAG_LEN);
427
428 val = dsa_xmit_port_mask(skb, dev);
429 val |= FIELD_PREP(LAN937X_TAIL_TAG_PRIO, prio);
430
431 if (is_link_local_ether_addr(hdr->h_dest))
432 val |= LAN937X_TAIL_TAG_BLOCKING_OVERRIDE;
433
434 /* Tail tag valid bit - This bit should always be set by the CPU */
435 val |= LAN937X_TAIL_TAG_VALID;
436
437 put_unaligned_be16(val, tag);
438
439 return ksz_defer_xmit(dp, skb);
440 }
441
442 static const struct dsa_device_ops lan937x_netdev_ops = {
443 .name = LAN937X_NAME,
444 .proto = DSA_TAG_PROTO_LAN937X,
445 .xmit = lan937x_xmit,
446 .rcv = ksz9477_rcv,
447 .connect = ksz_connect,
448 .disconnect = ksz_disconnect,
449 .needed_tailroom = LAN937X_EGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
450 };
451
452 DSA_TAG_DRIVER(lan937x_netdev_ops);
453 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_LAN937X, LAN937X_NAME);
454
455 static struct dsa_tag_driver *dsa_tag_driver_array[] = {
456 &DSA_TAG_DRIVER_NAME(ksz8795_netdev_ops),
457 &DSA_TAG_DRIVER_NAME(ksz9477_netdev_ops),
458 &DSA_TAG_DRIVER_NAME(ksz9893_netdev_ops),
459 &DSA_TAG_DRIVER_NAME(lan937x_netdev_ops),
460 };
461
462 module_dsa_tag_drivers(dsa_tag_driver_array);
463
464 MODULE_DESCRIPTION("DSA tag driver for Microchip 8795/937x/9477/9893 families of switches");
465 MODULE_LICENSE("GPL");
466