1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright (c) 2019, Vladimir Oltean <olteanv@gmail.com>
3 */
4 #include <linux/if_vlan.h>
5 #include <linux/dsa/sja1105.h>
6 #include <linux/dsa/8021q.h>
7 #include <linux/packing.h>
8
9 #include "tag.h"
10 #include "tag_8021q.h"
11
12 #define SJA1105_NAME "sja1105"
13 #define SJA1110_NAME "sja1110"
14
15 /* Is this a TX or an RX header? */
16 #define SJA1110_HEADER_HOST_TO_SWITCH BIT(15)
17
18 /* RX header */
19 #define SJA1110_RX_HEADER_IS_METADATA BIT(14)
20 #define SJA1110_RX_HEADER_HOST_ONLY BIT(13)
21 #define SJA1110_RX_HEADER_HAS_TRAILER BIT(12)
22
23 /* Trap-to-host format (no trailer present) */
24 #define SJA1110_RX_HEADER_SRC_PORT(x) (((x) & GENMASK(7, 4)) >> 4)
25 #define SJA1110_RX_HEADER_SWITCH_ID(x) ((x) & GENMASK(3, 0))
26
27 /* Timestamp format (trailer present) */
28 #define SJA1110_RX_HEADER_TRAILER_POS(x) ((x) & GENMASK(11, 0))
29
30 #define SJA1110_RX_TRAILER_SWITCH_ID(x) (((x) & GENMASK(7, 4)) >> 4)
31 #define SJA1110_RX_TRAILER_SRC_PORT(x) ((x) & GENMASK(3, 0))
32
33 /* Meta frame format (for 2-step TX timestamps) */
34 #define SJA1110_RX_HEADER_N_TS(x) (((x) & GENMASK(8, 4)) >> 4)
35
36 /* TX header */
37 #define SJA1110_TX_HEADER_UPDATE_TC BIT(14)
38 #define SJA1110_TX_HEADER_TAKE_TS BIT(13)
39 #define SJA1110_TX_HEADER_TAKE_TS_CASC BIT(12)
40 #define SJA1110_TX_HEADER_HAS_TRAILER BIT(11)
41
42 /* Only valid if SJA1110_TX_HEADER_HAS_TRAILER is false */
43 #define SJA1110_TX_HEADER_PRIO(x) (((x) << 7) & GENMASK(10, 7))
44 #define SJA1110_TX_HEADER_TSTAMP_ID(x) ((x) & GENMASK(7, 0))
45
46 /* Only valid if SJA1110_TX_HEADER_HAS_TRAILER is true */
47 #define SJA1110_TX_HEADER_TRAILER_POS(x) ((x) & GENMASK(10, 0))
48
49 #define SJA1110_TX_TRAILER_TSTAMP_ID(x) (((x) << 24) & GENMASK(31, 24))
50 #define SJA1110_TX_TRAILER_PRIO(x) (((x) << 21) & GENMASK(23, 21))
51 #define SJA1110_TX_TRAILER_SWITCHID(x) (((x) << 12) & GENMASK(15, 12))
52 #define SJA1110_TX_TRAILER_DESTPORTS(x) (((x) << 1) & GENMASK(11, 1))
53
54 #define SJA1110_META_TSTAMP_SIZE 10
55
56 #define SJA1110_HEADER_LEN 4
57 #define SJA1110_RX_TRAILER_LEN 13
58 #define SJA1110_TX_TRAILER_LEN 4
59 #define SJA1110_MAX_PADDING_LEN 15
60
61 struct sja1105_tagger_private {
62 struct sja1105_tagger_data data; /* Must be first */
63 /* Protects concurrent access to the meta state machine
64 * from taggers running on multiple ports on SMP systems
65 */
66 spinlock_t meta_lock;
67 struct sk_buff *stampable_skb;
68 struct kthread_worker *xmit_worker;
69 };
70
71 static struct sja1105_tagger_private *
72 sja1105_tagger_private(struct dsa_switch *ds)
73 {
74 return ds->tagger_data;
75 }
76
77 /* Similar to is_link_local_ether_addr(hdr->h_dest) but also covers PTP */
78 static bool sja1105_is_link_local(const struct sk_buff *skb)
79 {
80 const struct ethhdr *hdr = eth_hdr(skb);
81 u64 dmac = ether_addr_to_u64(hdr->h_dest);
82
83 if (ntohs(hdr->h_proto) == ETH_P_SJA1105_META)
84 return false;
85 if ((dmac & SJA1105_LINKLOCAL_FILTER_A_MASK) ==
86 SJA1105_LINKLOCAL_FILTER_A)
87 return true;
88 if ((dmac & SJA1105_LINKLOCAL_FILTER_B_MASK) ==
89 SJA1105_LINKLOCAL_FILTER_B)
90 return true;
91 return false;
92 }
93
94 struct sja1105_meta {
95 u64 tstamp;
96 u64 dmac_byte_4;
97 u64 dmac_byte_3;
98 u64 source_port;
99 u64 switch_id;
100 };
101
102 static void sja1105_meta_unpack(const struct sk_buff *skb,
103 struct sja1105_meta *meta)
104 {
105 u8 *buf = skb_mac_header(skb) + ETH_HLEN;
106
107 /* UM10944.pdf section 4.2.17 AVB Parameters:
108 * Structure of the meta-data follow-up frame.
109 * It is in network byte order, so there are no quirks
110 * while unpacking the meta frame.
111 *
112 * Also SJA1105 E/T only populates bits 23:0 of the timestamp
113 * whereas P/Q/R/S does 32 bits. Since the structure is the
114 * same and the E/T puts zeroes in the high-order byte, use
115 * a unified unpacking command for both device series.
116 */
117 packing(buf, &meta->tstamp, 31, 0, 4, UNPACK, 0);
118 packing(buf + 4, &meta->dmac_byte_3, 7, 0, 1, UNPACK, 0);
119 packing(buf + 5, &meta->dmac_byte_4, 7, 0, 1, UNPACK, 0);
120 packing(buf + 6, &meta->source_port, 7, 0, 1, UNPACK, 0);
121 packing(buf + 7, &meta->switch_id, 7, 0, 1, UNPACK, 0);
122 }
123
124 static bool sja1105_is_meta_frame(const struct sk_buff *skb)
125 {
126 const struct ethhdr *hdr = eth_hdr(skb);
127 u64 smac = ether_addr_to_u64(hdr->h_source);
128 u64 dmac = ether_addr_to_u64(hdr->h_dest);
129
130 if (smac != SJA1105_META_SMAC)
131 return false;
132 if (dmac != SJA1105_META_DMAC)
133 return false;
134 if (ntohs(hdr->h_proto) != ETH_P_SJA1105_META)
135 return false;
136 return true;
137 }
138
139 /* Calls sja1105_port_deferred_xmit in sja1105_main.c */
140 static struct sk_buff *sja1105_defer_xmit(struct dsa_port *dp,
141 struct sk_buff *skb)
142 {
143 struct sja1105_tagger_data *tagger_data = sja1105_tagger_data(dp->ds);
144 struct sja1105_tagger_private *priv = sja1105_tagger_private(dp->ds);
145 void (*xmit_work_fn)(struct kthread_work *work);
146 struct sja1105_deferred_xmit_work *xmit_work;
147 struct kthread_worker *xmit_worker;
148
149 xmit_work_fn = tagger_data->xmit_work_fn;
150 xmit_worker = priv->xmit_worker;
151
152 if (!xmit_work_fn || !xmit_worker)
153 return NULL;
154
155 xmit_work = kzalloc(sizeof(*xmit_work), GFP_ATOMIC);
156 if (!xmit_work)
157 return NULL;
158
159 kthread_init_work(&xmit_work->work, xmit_work_fn);
160 /* Increase refcount so the kfree_skb in dsa_user_xmit
161 * won't really free the packet.
162 */
163 xmit_work->dp = dp;
164 xmit_work->skb = skb_get(skb);
165
166 kthread_queue_work(xmit_worker, &xmit_work->work);
167
168 return NULL;
169 }
170
171 /* Send VLAN tags with a TPID that blends in with whatever VLAN protocol a
172 * bridge spanning ports of this switch might have.
173 */
174 static u16 sja1105_xmit_tpid(struct dsa_port *dp)
175 {
176 struct dsa_switch *ds = dp->ds;
177 struct dsa_port *other_dp;
178 u16 proto;
179
180 /* Since VLAN awareness is global, then if this port is VLAN-unaware,
181 * all ports are. Use the VLAN-unaware TPID used for tag_8021q.
182 */
183 if (!dsa_port_is_vlan_filtering(dp))
184 return ETH_P_SJA1105;
185
186 /* Port is VLAN-aware, so there is a bridge somewhere (a single one,
187 * we're sure about that). It may not be on this port though, so we
188 * need to find it.
189 */
190 dsa_switch_for_each_port(other_dp, ds) {
191 struct net_device *br = dsa_port_bridge_dev_get(other_dp);
192
193 if (!br)
194 continue;
195
196 /* Error is returned only if CONFIG_BRIDGE_VLAN_FILTERING,
197 * which seems pointless to handle, as our port cannot become
198 * VLAN-aware in that case.
199 */
200 br_vlan_get_proto(br, &proto);
201
202 return proto;
203 }
204
205 WARN_ONCE(1, "Port is VLAN-aware but cannot find associated bridge!\n");
206
207 return ETH_P_SJA1105;
208 }
209
210 static struct sk_buff *sja1105_imprecise_xmit(struct sk_buff *skb,
211 struct net_device *netdev)
212 {
213 struct dsa_port *dp = dsa_user_to_port(netdev);
214 unsigned int bridge_num = dsa_port_bridge_num_get(dp);
215 struct net_device *br = dsa_port_bridge_dev_get(dp);
216 u16 tx_vid;
217
218 /* If the port is under a VLAN-aware bridge, just slide the
219 * VLAN-tagged packet into the FDB and hope for the best.
220 * This works because we support a single VLAN-aware bridge
221 * across the entire dst, and its VLANs cannot be shared with
222 * any standalone port.
223 */
224 if (br_vlan_enabled(br))
225 return skb;
226
227 /* If the port is under a VLAN-unaware bridge, use an imprecise
228 * TX VLAN that targets the bridge's entire broadcast domain,
229 * instead of just the specific port.
230 */
231 tx_vid = dsa_tag_8021q_bridge_vid(bridge_num);
232
233 return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp), tx_vid);
234 }
235
236 /* Transform untagged control packets into pvid-tagged control packets so that
237 * all packets sent by this tagger are VLAN-tagged and we can configure the
238 * switch to drop untagged packets coming from the DSA conduit.
239 */
240 static struct sk_buff *sja1105_pvid_tag_control_pkt(struct dsa_port *dp,
241 struct sk_buff *skb, u8 pcp)
242 {
243 __be16 xmit_tpid = htons(sja1105_xmit_tpid(dp));
244 struct vlan_ethhdr *hdr;
245
246 /* If VLAN tag is in hwaccel area, move it to the payload
247 * to deal with both cases uniformly and to ensure that
248 * the VLANs are added in the right order.
249 */
250 if (unlikely(skb_vlan_tag_present(skb))) {
251 skb = __vlan_hwaccel_push_inside(skb);
252 if (!skb)
253 return NULL;
254 }
255
256 hdr = skb_vlan_eth_hdr(skb);
257
258 /* If skb is already VLAN-tagged, leave that VLAN ID in place */
259 if (hdr->h_vlan_proto == xmit_tpid)
260 return skb;
261
262 return vlan_insert_tag(skb, xmit_tpid, (pcp << VLAN_PRIO_SHIFT) |
263 SJA1105_DEFAULT_VLAN);
264 }
265
266 static struct sk_buff *sja1105_xmit(struct sk_buff *skb,
267 struct net_device *netdev)
268 {
269 struct dsa_port *dp = dsa_user_to_port(netdev);
270 u16 queue_mapping = skb_get_queue_mapping(skb);
271 u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
272 u16 tx_vid = dsa_tag_8021q_standalone_vid(dp);
273
274 if (skb->offload_fwd_mark)
275 return sja1105_imprecise_xmit(skb, netdev);
276
277 /* Transmitting management traffic does not rely upon switch tagging,
278 * but instead SPI-installed management routes. Part 2 of this
279 * is the .port_deferred_xmit driver callback.
280 */
281 if (unlikely(sja1105_is_link_local(skb))) {
282 skb = sja1105_pvid_tag_control_pkt(dp, skb, pcp);
283 if (!skb)
284 return NULL;
285
286 return sja1105_defer_xmit(dp, skb);
287 }
288
289 return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp),
290 ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
291 }
292
293 static struct sk_buff *sja1110_xmit(struct sk_buff *skb,
294 struct net_device *netdev)
295 {
296 struct sk_buff *clone = SJA1105_SKB_CB(skb)->clone;
297 struct dsa_port *dp = dsa_user_to_port(netdev);
298 u16 queue_mapping = skb_get_queue_mapping(skb);
299 u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
300 u16 tx_vid = dsa_tag_8021q_standalone_vid(dp);
301 __be32 *tx_trailer;
302 __be16 *tx_header;
303 int trailer_pos;
304
305 if (skb->offload_fwd_mark)
306 return sja1105_imprecise_xmit(skb, netdev);
307
308 /* Transmitting control packets is done using in-band control
309 * extensions, while data packets are transmitted using
310 * tag_8021q TX VLANs.
311 */
312 if (likely(!sja1105_is_link_local(skb)))
313 return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp),
314 ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
315
316 skb = sja1105_pvid_tag_control_pkt(dp, skb, pcp);
317 if (!skb)
318 return NULL;
319
320 skb_push(skb, SJA1110_HEADER_LEN);
321
322 dsa_alloc_etype_header(skb, SJA1110_HEADER_LEN);
323
324 trailer_pos = skb->len;
325
326 tx_header = dsa_etype_header_pos_tx(skb);
327 tx_trailer = skb_put(skb, SJA1110_TX_TRAILER_LEN);
328
329 tx_header[0] = htons(ETH_P_SJA1110);
330 tx_header[1] = htons(SJA1110_HEADER_HOST_TO_SWITCH |
331 SJA1110_TX_HEADER_HAS_TRAILER |
332 SJA1110_TX_HEADER_TRAILER_POS(trailer_pos));
333 *tx_trailer = cpu_to_be32(SJA1110_TX_TRAILER_PRIO(pcp) |
334 SJA1110_TX_TRAILER_SWITCHID(dp->ds->index) |
335 SJA1110_TX_TRAILER_DESTPORTS(BIT(dp->index)));
336 if (clone) {
337 u8 ts_id = SJA1105_SKB_CB(clone)->ts_id;
338
339 tx_header[1] |= htons(SJA1110_TX_HEADER_TAKE_TS);
340 *tx_trailer |= cpu_to_be32(SJA1110_TX_TRAILER_TSTAMP_ID(ts_id));
341 }
342
343 return skb;
344 }
345
346 static void sja1105_transfer_meta(struct sk_buff *skb,
347 const struct sja1105_meta *meta)
348 {
349 struct ethhdr *hdr = eth_hdr(skb);
350
351 hdr->h_dest[3] = meta->dmac_byte_3;
352 hdr->h_dest[4] = meta->dmac_byte_4;
353 SJA1105_SKB_CB(skb)->tstamp = meta->tstamp;
354 }
355
356 /* This is a simple state machine which follows the hardware mechanism of
357 * generating RX timestamps:
358 *
359 * After each timestampable skb (all traffic for which send_meta1 and
360 * send_meta0 is true, aka all MAC-filtered link-local traffic) a meta frame
361 * containing a partial timestamp is immediately generated by the switch and
362 * sent as a follow-up to the link-local frame on the CPU port.
363 *
364 * The meta frames have no unique identifier (such as sequence number) by which
365 * one may pair them to the correct timestampable frame.
366 * Instead, the switch has internal logic that ensures no frames are sent on
367 * the CPU port between a link-local timestampable frame and its corresponding
368 * meta follow-up. It also ensures strict ordering between ports (lower ports
369 * have higher priority towards the CPU port). For this reason, a per-port
370 * data structure is not needed/desirable.
371 *
372 * This function pairs the link-local frame with its partial timestamp from the
373 * meta follow-up frame. The full timestamp will be reconstructed later in a
374 * work queue.
375 */
376 static struct sk_buff
377 *sja1105_rcv_meta_state_machine(struct sk_buff *skb,
378 struct sja1105_meta *meta,
379 bool is_link_local,
380 bool is_meta)
381 {
382 /* Step 1: A timestampable frame was received.
383 * Buffer it until we get its meta frame.
384 */
385 if (is_link_local) {
386 struct dsa_port *dp = dsa_user_to_port(skb->dev);
387 struct sja1105_tagger_private *priv;
388 struct dsa_switch *ds = dp->ds;
389
390 priv = sja1105_tagger_private(ds);
391
392 spin_lock(&priv->meta_lock);
393 /* Was this a link-local frame instead of the meta
394 * that we were expecting?
395 */
396 if (priv->stampable_skb) {
397 dev_err_ratelimited(ds->dev,
398 "Expected meta frame, is %12llx "
399 "in the DSA conduit multicast filter?\n",
400 SJA1105_META_DMAC);
401 kfree_skb(priv->stampable_skb);
402 }
403
404 /* Hold a reference to avoid dsa_switch_rcv
405 * from freeing the skb.
406 */
407 priv->stampable_skb = skb_get(skb);
408 spin_unlock(&priv->meta_lock);
409
410 /* Tell DSA we got nothing */
411 return NULL;
412
413 /* Step 2: The meta frame arrived.
414 * Time to take the stampable skb out of the closet, annotate it
415 * with the partial timestamp, and pretend that we received it
416 * just now (basically masquerade the buffered frame as the meta
417 * frame, which serves no further purpose).
418 */
419 } else if (is_meta) {
420 struct dsa_port *dp = dsa_user_to_port(skb->dev);
421 struct sja1105_tagger_private *priv;
422 struct dsa_switch *ds = dp->ds;
423 struct sk_buff *stampable_skb;
424
425 priv = sja1105_tagger_private(ds);
426
427 spin_lock(&priv->meta_lock);
428
429 stampable_skb = priv->stampable_skb;
430 priv->stampable_skb = NULL;
431
432 /* Was this a meta frame instead of the link-local
433 * that we were expecting?
434 */
435 if (!stampable_skb) {
436 dev_err_ratelimited(ds->dev,
437 "Unexpected meta frame\n");
438 spin_unlock(&priv->meta_lock);
439 return NULL;
440 }
441
442 if (stampable_skb->dev != skb->dev) {
443 dev_err_ratelimited(ds->dev,
444 "Meta frame on wrong port\n");
445 spin_unlock(&priv->meta_lock);
446 return NULL;
447 }
448
449 /* Free the meta frame and give DSA the buffered stampable_skb
450 * for further processing up the network stack.
451 */
452 kfree_skb(skb);
453 skb = stampable_skb;
454 sja1105_transfer_meta(skb, meta);
455
456 spin_unlock(&priv->meta_lock);
457 }
458
459 return skb;
460 }
461
462 static bool sja1105_skb_has_tag_8021q(const struct sk_buff *skb)
463 {
464 u16 tpid = ntohs(eth_hdr(skb)->h_proto);
465
466 return tpid == ETH_P_SJA1105 || tpid == ETH_P_8021Q ||
467 skb_vlan_tag_present(skb);
468 }
469
470 static bool sja1110_skb_has_inband_control_extension(const struct sk_buff *skb)
471 {
472 return ntohs(eth_hdr(skb)->h_proto) == ETH_P_SJA1110;
473 }
474
475 static struct sk_buff *sja1105_rcv(struct sk_buff *skb,
476 struct net_device *netdev)
477 {
478 int source_port = -1, switch_id = -1, vbid = -1, vid = -1;
479 struct sja1105_meta meta = {0};
480 struct ethhdr *hdr;
481 bool is_link_local;
482 bool is_meta;
483
484 hdr = eth_hdr(skb);
485 is_link_local = sja1105_is_link_local(skb);
486 is_meta = sja1105_is_meta_frame(skb);
487
488 if (is_link_local) {
489 /* Management traffic path. Switch embeds the switch ID and
490 * port ID into bytes of the destination MAC, courtesy of
491 * the incl_srcpt options.
492 */
493 source_port = hdr->h_dest[3];
494 switch_id = hdr->h_dest[4];
495 } else if (is_meta) {
496 sja1105_meta_unpack(skb, &meta);
497 source_port = meta.source_port;
498 switch_id = meta.switch_id;
499 }
500
501 /* Normal data plane traffic and link-local frames are tagged with
502 * a tag_8021q VLAN which we have to strip
503 */
504 if (sja1105_skb_has_tag_8021q(skb))
505 dsa_8021q_rcv(skb, &source_port, &switch_id, &vbid, &vid);
506 else if (source_port == -1 && switch_id == -1)
507 /* Packets with no source information have no chance of
508 * getting accepted, drop them straight away.
509 */
510 return NULL;
511
512 skb->dev = dsa_tag_8021q_find_user(netdev, source_port, switch_id,
513 vid, vbid);
514 if (!skb->dev) {
515 netdev_warn(netdev, "Couldn't decode source port\n");
516 return NULL;
517 }
518
519 if (!is_link_local)
520 dsa_default_offload_fwd_mark(skb);
521
522 return sja1105_rcv_meta_state_machine(skb, &meta, is_link_local,
523 is_meta);
524 }
525
526 static struct sk_buff *sja1110_rcv_meta(struct sk_buff *skb, u16 rx_header)
527 {
528 u8 *buf = dsa_etype_header_pos_rx(skb) + SJA1110_HEADER_LEN;
529 int switch_id = SJA1110_RX_HEADER_SWITCH_ID(rx_header);
530 int n_ts = SJA1110_RX_HEADER_N_TS(rx_header);
531 struct sja1105_tagger_data *tagger_data;
532 struct net_device *conduit = skb->dev;
533 struct dsa_port *cpu_dp;
534 struct dsa_switch *ds;
535 int i;
536
537 cpu_dp = conduit->dsa_ptr;
538 ds = dsa_switch_find(cpu_dp->dst->index, switch_id);
539 if (!ds) {
540 net_err_ratelimited("%s: cannot find switch id %d\n",
541 conduit->name, switch_id);
542 return NULL;
543 }
544
545 tagger_data = sja1105_tagger_data(ds);
546 if (!tagger_data->meta_tstamp_handler)
547 return NULL;
548
549 for (i = 0; i <= n_ts; i++) {
550 u8 ts_id, source_port, dir;
551 u64 tstamp;
552
553 ts_id = buf[0];
554 source_port = (buf[1] & GENMASK(7, 4)) >> 4;
555 dir = (buf[1] & BIT(3)) >> 3;
556 tstamp = be64_to_cpu(*(__be64 *)(buf + 2));
557
558 tagger_data->meta_tstamp_handler(ds, source_port, ts_id, dir,
559 tstamp);
560
561 buf += SJA1110_META_TSTAMP_SIZE;
562 }
563
564 /* Discard the meta frame, we've consumed the timestamps it contained */
565 return NULL;
566 }
567
568 static struct sk_buff *sja1110_rcv_inband_control_extension(struct sk_buff *skb,
569 int *source_port,
570 int *switch_id,
571 bool *host_only)
572 {
573 u16 rx_header;
574
575 if (unlikely(!pskb_may_pull(skb, SJA1110_HEADER_LEN)))
576 return NULL;
577
578 /* skb->data points to skb_mac_header(skb) + ETH_HLEN, which is exactly
579 * what we need because the caller has checked the EtherType (which is
580 * located 2 bytes back) and we just need a pointer to the header that
581 * comes afterwards.
582 */
583 rx_header = ntohs(*(__be16 *)skb->data);
584
585 if (rx_header & SJA1110_RX_HEADER_HOST_ONLY)
586 *host_only = true;
587
588 if (rx_header & SJA1110_RX_HEADER_IS_METADATA)
589 return sja1110_rcv_meta(skb, rx_header);
590
591 /* Timestamp frame, we have a trailer */
592 if (rx_header & SJA1110_RX_HEADER_HAS_TRAILER) {
593 int start_of_padding = SJA1110_RX_HEADER_TRAILER_POS(rx_header);
594 u8 *rx_trailer = skb_tail_pointer(skb) - SJA1110_RX_TRAILER_LEN;
595 u64 *tstamp = &SJA1105_SKB_CB(skb)->tstamp;
596 u8 last_byte = rx_trailer[12];
597
598 /* The timestamp is unaligned, so we need to use packing()
599 * to get it
600 */
601 packing(rx_trailer, tstamp, 63, 0, 8, UNPACK, 0);
602
603 *source_port = SJA1110_RX_TRAILER_SRC_PORT(last_byte);
604 *switch_id = SJA1110_RX_TRAILER_SWITCH_ID(last_byte);
605
606 /* skb->len counts from skb->data, while start_of_padding
607 * counts from the destination MAC address. Right now skb->data
608 * is still as set by the DSA conduit, so to trim away the
609 * padding and trailer we need to account for the fact that
610 * skb->data points to skb_mac_header(skb) + ETH_HLEN.
611 */
612 if (pskb_trim_rcsum(skb, start_of_padding - ETH_HLEN))
613 return NULL;
614 /* Trap-to-host frame, no timestamp trailer */
615 } else {
616 *source_port = SJA1110_RX_HEADER_SRC_PORT(rx_header);
617 *switch_id = SJA1110_RX_HEADER_SWITCH_ID(rx_header);
618 }
619
620 /* Advance skb->data past the DSA header */
621 skb_pull_rcsum(skb, SJA1110_HEADER_LEN);
622
623 dsa_strip_etype_header(skb, SJA1110_HEADER_LEN);
624
625 /* With skb->data in its final place, update the MAC header
626 * so that eth_hdr() continues to works properly.
627 */
628 skb_set_mac_header(skb, -ETH_HLEN);
629
630 return skb;
631 }
632
633 static struct sk_buff *sja1110_rcv(struct sk_buff *skb,
634 struct net_device *netdev)
635 {
636 int source_port = -1, switch_id = -1, vbid = -1, vid = -1;
637 bool host_only = false;
638
639 if (sja1110_skb_has_inband_control_extension(skb)) {
640 skb = sja1110_rcv_inband_control_extension(skb, &source_port,
641 &switch_id,
642 &host_only);
643 if (!skb)
644 return NULL;
645 }
646
647 /* Packets with in-band control extensions might still have RX VLANs */
648 if (likely(sja1105_skb_has_tag_8021q(skb)))
649 dsa_8021q_rcv(skb, &source_port, &switch_id, &vbid, &vid);
650
651 skb->dev = dsa_tag_8021q_find_user(netdev, source_port, switch_id,
652 vid, vbid);
653
654 if (!skb->dev) {
655 netdev_warn(netdev, "Couldn't decode source port\n");
656 return NULL;
657 }
658
659 if (!host_only)
660 dsa_default_offload_fwd_mark(skb);
661
662 return skb;
663 }
664
665 static void sja1105_flow_dissect(const struct sk_buff *skb, __be16 *proto,
666 int *offset)
667 {
668 /* No tag added for management frames, all ok */
669 if (unlikely(sja1105_is_link_local(skb)))
670 return;
671
672 dsa_tag_generic_flow_dissect(skb, proto, offset);
673 }
674
675 static void sja1110_flow_dissect(const struct sk_buff *skb, __be16 *proto,
676 int *offset)
677 {
678 /* Management frames have 2 DSA tags on RX, so the needed_headroom we
679 * declared is fine for the generic dissector adjustment procedure.
680 */
681 if (unlikely(sja1105_is_link_local(skb)))
682 return dsa_tag_generic_flow_dissect(skb, proto, offset);
683
684 /* For the rest, there is a single DSA tag, the tag_8021q one */
685 *offset = VLAN_HLEN;
686 *proto = ((__be16 *)skb->data)[(VLAN_HLEN / 2) - 1];
687 }
688
689 static void sja1105_disconnect(struct dsa_switch *ds)
690 {
691 struct sja1105_tagger_private *priv = ds->tagger_data;
692
693 kthread_destroy_worker(priv->xmit_worker);
694 kfree(priv);
695 ds->tagger_data = NULL;
696 }
697
698 static int sja1105_connect(struct dsa_switch *ds)
699 {
700 struct sja1105_tagger_private *priv;
701 struct kthread_worker *xmit_worker;
702 int err;
703
704 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
705 if (!priv)
706 return -ENOMEM;
707
708 spin_lock_init(&priv->meta_lock);
709
710 xmit_worker = kthread_create_worker(0, "dsa%d:%d_xmit",
711 ds->dst->index, ds->index);
712 if (IS_ERR(xmit_worker)) {
713 err = PTR_ERR(xmit_worker);
714 kfree(priv);
715 return err;
716 }
717
718 priv->xmit_worker = xmit_worker;
719 ds->tagger_data = priv;
720
721 return 0;
722 }
723
724 static const struct dsa_device_ops sja1105_netdev_ops = {
725 .name = SJA1105_NAME,
726 .proto = DSA_TAG_PROTO_SJA1105,
727 .xmit = sja1105_xmit,
728 .rcv = sja1105_rcv,
729 .connect = sja1105_connect,
730 .disconnect = sja1105_disconnect,
731 .needed_headroom = VLAN_HLEN,
732 .flow_dissect = sja1105_flow_dissect,
733 .promisc_on_conduit = true,
734 };
735
736 DSA_TAG_DRIVER(sja1105_netdev_ops);
737 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1105, SJA1105_NAME);
738
739 static const struct dsa_device_ops sja1110_netdev_ops = {
740 .name = SJA1110_NAME,
741 .proto = DSA_TAG_PROTO_SJA1110,
742 .xmit = sja1110_xmit,
743 .rcv = sja1110_rcv,
744 .connect = sja1105_connect,
745 .disconnect = sja1105_disconnect,
746 .flow_dissect = sja1110_flow_dissect,
747 .needed_headroom = SJA1110_HEADER_LEN + VLAN_HLEN,
748 .needed_tailroom = SJA1110_RX_TRAILER_LEN + SJA1110_MAX_PADDING_LEN,
749 };
750
751 DSA_TAG_DRIVER(sja1110_netdev_ops);
752 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1110, SJA1110_NAME);
753
754 static struct dsa_tag_driver *sja1105_tag_driver_array[] = {
755 &DSA_TAG_DRIVER_NAME(sja1105_netdev_ops),
756 &DSA_TAG_DRIVER_NAME(sja1110_netdev_ops),
757 };
758
759 module_dsa_tag_drivers(sja1105_tag_driver_array);
760
761 MODULE_DESCRIPTION("DSA tag driver for NXP SJA1105 switches");
762 MODULE_LICENSE("GPL v2");
763
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