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_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 dsa_port *dp = dsa_user_to_port(dev);
124 struct ethhdr *hdr;
125 u8 *tag;
126
127 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
128 return NULL;
129
130 /* Tag encoding */
131 tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);
132 hdr = skb_eth_hdr(skb);
133
134 *tag = 1 << dp->index;
135 if (is_link_local_ether_addr(hdr->h_dest))
136 *tag |= KSZ8795_TAIL_TAG_OVERRIDE;
137
138 return skb;
139 }
140
ksz8795_rcv(struct sk_buff * skb,struct net_device * dev)141 static struct sk_buff *ksz8795_rcv(struct sk_buff *skb, struct net_device *dev)
142 {
143 u8 *tag;
144
145 if (skb_linearize(skb))
146 return NULL;
147
148 tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
149
150 return ksz_common_rcv(skb, dev, tag[0] & KSZ8795_TAIL_TAG_EG_PORT_M,
151 KSZ_EGRESS_TAG_LEN);
152 }
153
154 static const struct dsa_device_ops ksz8795_netdev_ops = {
155 .name = KSZ8795_NAME,
156 .proto = DSA_TAG_PROTO_KSZ8795,
157 .xmit = ksz8795_xmit,
158 .rcv = ksz8795_rcv,
159 .needed_tailroom = KSZ_INGRESS_TAG_LEN,
160 };
161
162 DSA_TAG_DRIVER(ksz8795_netdev_ops);
163 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795, KSZ8795_NAME);
164
165 /*
166 * For Ingress (Host -> KSZ9477), 2/6 bytes are added before FCS.
167 * ---------------------------------------------------------------------------
168 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|tag1(1byte)|
169 * FCS(4bytes)
170 * ---------------------------------------------------------------------------
171 * ts : time stamp (Present only if PTP is enabled in the Hardware)
172 * tag0 : Prioritization (not used now)
173 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
174 *
175 * For Egress (KSZ9477 -> Host), 1/5 bytes is added before FCS.
176 * ---------------------------------------------------------------------------
177 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes)
178 * ---------------------------------------------------------------------------
179 * ts : time stamp (Present only if bit 7 of tag0 is set)
180 * tag0 : zero-based value represents port
181 * (eg, 0x00=port1, 0x02=port3, 0x06=port7)
182 */
183
184 #define KSZ9477_INGRESS_TAG_LEN 2
185 #define KSZ9477_PTP_TAG_LEN 4
186 #define KSZ9477_PTP_TAG_INDICATION BIT(7)
187
188 #define KSZ9477_TAIL_TAG_EG_PORT_M GENMASK(2, 0)
189 #define KSZ9477_TAIL_TAG_PRIO GENMASK(8, 7)
190 #define KSZ9477_TAIL_TAG_OVERRIDE BIT(9)
191 #define KSZ9477_TAIL_TAG_LOOKUP BIT(10)
192
ksz_rcv_timestamp(struct sk_buff * skb,u8 * tag)193 static void ksz_rcv_timestamp(struct sk_buff *skb, u8 *tag)
194 {
195 u8 *tstamp_raw = tag - KSZ_PTP_TAG_LEN;
196 ktime_t tstamp;
197
198 tstamp = ksz_decode_tstamp(get_unaligned_be32(tstamp_raw));
199 KSZ_SKB_CB(skb)->tstamp = tstamp;
200 }
201
202 /* Time stamp tag *needs* to be inserted if PTP is enabled in hardware.
203 * Regardless of Whether it is a PTP frame or not.
204 */
ksz_xmit_timestamp(struct dsa_port * dp,struct sk_buff * skb)205 static void ksz_xmit_timestamp(struct dsa_port *dp, struct sk_buff *skb)
206 {
207 struct ksz_tagger_private *priv;
208 struct ptp_header *ptp_hdr;
209 unsigned int ptp_type;
210 u32 tstamp_raw = 0;
211 s64 correction;
212
213 priv = ksz_tagger_private(dp->ds);
214
215 if (!test_bit(KSZ_HWTS_EN, &priv->state))
216 return;
217
218 if (!KSZ_SKB_CB(skb)->update_correction)
219 goto output_tag;
220
221 ptp_type = KSZ_SKB_CB(skb)->ptp_type;
222
223 ptp_hdr = ptp_parse_header(skb, ptp_type);
224 if (!ptp_hdr)
225 goto output_tag;
226
227 correction = (s64)get_unaligned_be64(&ptp_hdr->correction);
228
229 if (correction < 0) {
230 struct timespec64 ts;
231
232 ts = ns_to_timespec64(-correction >> 16);
233 tstamp_raw = ((ts.tv_sec & 3) << 30) | ts.tv_nsec;
234
235 /* Set correction field to 0 and update UDP checksum */
236 ptp_header_update_correction(skb, ptp_type, ptp_hdr, 0);
237 }
238
239 output_tag:
240 put_unaligned_be32(tstamp_raw, skb_put(skb, KSZ_PTP_TAG_LEN));
241 }
242
243 /* Defer transmit if waiting for egress time stamp is required. */
ksz_defer_xmit(struct dsa_port * dp,struct sk_buff * skb)244 static struct sk_buff *ksz_defer_xmit(struct dsa_port *dp, struct sk_buff *skb)
245 {
246 struct ksz_tagger_data *tagger_data = ksz_tagger_data(dp->ds);
247 struct ksz_tagger_private *priv = ksz_tagger_private(dp->ds);
248 void (*xmit_work_fn)(struct kthread_work *work);
249 struct sk_buff *clone = KSZ_SKB_CB(skb)->clone;
250 struct ksz_deferred_xmit_work *xmit_work;
251 struct kthread_worker *xmit_worker;
252
253 if (!clone)
254 return skb; /* no deferred xmit for this packet */
255
256 xmit_work_fn = tagger_data->xmit_work_fn;
257 xmit_worker = priv->xmit_worker;
258
259 if (!xmit_work_fn || !xmit_worker)
260 return NULL;
261
262 xmit_work = kzalloc(sizeof(*xmit_work), GFP_ATOMIC);
263 if (!xmit_work)
264 return NULL;
265
266 kthread_init_work(&xmit_work->work, xmit_work_fn);
267 /* Increase refcount so the kfree_skb in dsa_user_xmit
268 * won't really free the packet.
269 */
270 xmit_work->dp = dp;
271 xmit_work->skb = skb_get(skb);
272
273 kthread_queue_work(xmit_worker, &xmit_work->work);
274
275 return NULL;
276 }
277
ksz9477_xmit(struct sk_buff * skb,struct net_device * dev)278 static struct sk_buff *ksz9477_xmit(struct sk_buff *skb,
279 struct net_device *dev)
280 {
281 u16 queue_mapping = skb_get_queue_mapping(skb);
282 u8 prio = netdev_txq_to_tc(dev, queue_mapping);
283 struct dsa_port *dp = dsa_user_to_port(dev);
284 struct ethhdr *hdr;
285 __be16 *tag;
286 u16 val;
287
288 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
289 return NULL;
290
291 /* Tag encoding */
292 ksz_xmit_timestamp(dp, skb);
293
294 tag = skb_put(skb, KSZ9477_INGRESS_TAG_LEN);
295 hdr = skb_eth_hdr(skb);
296
297 val = BIT(dp->index);
298
299 val |= FIELD_PREP(KSZ9477_TAIL_TAG_PRIO, prio);
300
301 if (is_link_local_ether_addr(hdr->h_dest))
302 val |= KSZ9477_TAIL_TAG_OVERRIDE;
303
304 if (dev->features & NETIF_F_HW_HSR_DUP) {
305 struct net_device *hsr_dev = dp->hsr_dev;
306 struct dsa_port *other_dp;
307
308 dsa_hsr_foreach_port(other_dp, dp->ds, hsr_dev)
309 val |= BIT(other_dp->index);
310 }
311
312 *tag = cpu_to_be16(val);
313
314 return ksz_defer_xmit(dp, skb);
315 }
316
ksz9477_rcv(struct sk_buff * skb,struct net_device * dev)317 static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev)
318 {
319 unsigned int len = KSZ_EGRESS_TAG_LEN;
320 unsigned int port;
321 u8 *tag;
322
323 if (skb_linearize(skb))
324 return NULL;
325
326 /* Tag decoding */
327 tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
328 port = tag[0] & KSZ9477_TAIL_TAG_EG_PORT_M;
329
330 /* Extra 4-bytes PTP timestamp */
331 if (tag[0] & KSZ9477_PTP_TAG_INDICATION) {
332 ksz_rcv_timestamp(skb, tag);
333 len += KSZ_PTP_TAG_LEN;
334 }
335
336 return ksz_common_rcv(skb, dev, port, len);
337 }
338
339 static const struct dsa_device_ops ksz9477_netdev_ops = {
340 .name = KSZ9477_NAME,
341 .proto = DSA_TAG_PROTO_KSZ9477,
342 .xmit = ksz9477_xmit,
343 .rcv = ksz9477_rcv,
344 .connect = ksz_connect,
345 .disconnect = ksz_disconnect,
346 .needed_tailroom = KSZ9477_INGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
347 };
348
349 DSA_TAG_DRIVER(ksz9477_netdev_ops);
350 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9477, KSZ9477_NAME);
351
352 #define KSZ9893_TAIL_TAG_PRIO GENMASK(4, 3)
353 #define KSZ9893_TAIL_TAG_OVERRIDE BIT(5)
354 #define KSZ9893_TAIL_TAG_LOOKUP BIT(6)
355
ksz9893_xmit(struct sk_buff * skb,struct net_device * dev)356 static struct sk_buff *ksz9893_xmit(struct sk_buff *skb,
357 struct net_device *dev)
358 {
359 u16 queue_mapping = skb_get_queue_mapping(skb);
360 u8 prio = netdev_txq_to_tc(dev, queue_mapping);
361 struct dsa_port *dp = dsa_user_to_port(dev);
362 struct ethhdr *hdr;
363 u8 *tag;
364
365 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
366 return NULL;
367
368 /* Tag encoding */
369 ksz_xmit_timestamp(dp, skb);
370
371 tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);
372 hdr = skb_eth_hdr(skb);
373
374 *tag = BIT(dp->index);
375
376 *tag |= FIELD_PREP(KSZ9893_TAIL_TAG_PRIO, prio);
377
378 if (is_link_local_ether_addr(hdr->h_dest))
379 *tag |= KSZ9893_TAIL_TAG_OVERRIDE;
380
381 return ksz_defer_xmit(dp, skb);
382 }
383
384 static const struct dsa_device_ops ksz9893_netdev_ops = {
385 .name = KSZ9893_NAME,
386 .proto = DSA_TAG_PROTO_KSZ9893,
387 .xmit = ksz9893_xmit,
388 .rcv = ksz9477_rcv,
389 .connect = ksz_connect,
390 .disconnect = ksz_disconnect,
391 .needed_tailroom = KSZ_INGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
392 };
393
394 DSA_TAG_DRIVER(ksz9893_netdev_ops);
395 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893, KSZ9893_NAME);
396
397 /* For xmit, 2/6 bytes are added before FCS.
398 * ---------------------------------------------------------------------------
399 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|tag1(1byte)|
400 * FCS(4bytes)
401 * ---------------------------------------------------------------------------
402 * ts : time stamp (Present only if PTP is enabled in the Hardware)
403 * tag0 : represents tag override, lookup and valid
404 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x80=port8)
405 *
406 * For rcv, 1/5 bytes is added before FCS.
407 * ---------------------------------------------------------------------------
408 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes)
409 * ---------------------------------------------------------------------------
410 * ts : time stamp (Present only if bit 7 of tag0 is set)
411 * tag0 : zero-based value represents port
412 * (eg, 0x00=port1, 0x02=port3, 0x07=port8)
413 */
414 #define LAN937X_EGRESS_TAG_LEN 2
415
416 #define LAN937X_TAIL_TAG_BLOCKING_OVERRIDE BIT(11)
417 #define LAN937X_TAIL_TAG_LOOKUP BIT(12)
418 #define LAN937X_TAIL_TAG_VALID BIT(13)
419 #define LAN937X_TAIL_TAG_PRIO GENMASK(10, 8)
420 #define LAN937X_TAIL_TAG_PORT_MASK 7
421
lan937x_xmit(struct sk_buff * skb,struct net_device * dev)422 static struct sk_buff *lan937x_xmit(struct sk_buff *skb,
423 struct net_device *dev)
424 {
425 u16 queue_mapping = skb_get_queue_mapping(skb);
426 u8 prio = netdev_txq_to_tc(dev, queue_mapping);
427 struct dsa_port *dp = dsa_user_to_port(dev);
428 const struct ethhdr *hdr = eth_hdr(skb);
429 __be16 *tag;
430 u16 val;
431
432 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
433 return NULL;
434
435 ksz_xmit_timestamp(dp, skb);
436
437 tag = skb_put(skb, LAN937X_EGRESS_TAG_LEN);
438
439 val = BIT(dp->index);
440
441 val |= FIELD_PREP(LAN937X_TAIL_TAG_PRIO, prio);
442
443 if (is_link_local_ether_addr(hdr->h_dest))
444 val |= LAN937X_TAIL_TAG_BLOCKING_OVERRIDE;
445
446 /* Tail tag valid bit - This bit should always be set by the CPU */
447 val |= LAN937X_TAIL_TAG_VALID;
448
449 put_unaligned_be16(val, tag);
450
451 return ksz_defer_xmit(dp, skb);
452 }
453
454 static const struct dsa_device_ops lan937x_netdev_ops = {
455 .name = LAN937X_NAME,
456 .proto = DSA_TAG_PROTO_LAN937X,
457 .xmit = lan937x_xmit,
458 .rcv = ksz9477_rcv,
459 .connect = ksz_connect,
460 .disconnect = ksz_disconnect,
461 .needed_tailroom = LAN937X_EGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
462 };
463
464 DSA_TAG_DRIVER(lan937x_netdev_ops);
465 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_LAN937X, LAN937X_NAME);
466
467 static struct dsa_tag_driver *dsa_tag_driver_array[] = {
468 &DSA_TAG_DRIVER_NAME(ksz8795_netdev_ops),
469 &DSA_TAG_DRIVER_NAME(ksz9477_netdev_ops),
470 &DSA_TAG_DRIVER_NAME(ksz9893_netdev_ops),
471 &DSA_TAG_DRIVER_NAME(lan937x_netdev_ops),
472 };
473
474 module_dsa_tag_drivers(dsa_tag_driver_array);
475
476 MODULE_DESCRIPTION("DSA tag driver for Microchip 8795/937x/9477/9893 families of switches");
477 MODULE_LICENSE("GPL");
478