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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#include "dsa_priv.h"
9
10/* Is this a TX or an RX header? */
11#define SJA1110_HEADER_HOST_TO_SWITCH BIT(15)
12
13/* RX header */
14#define SJA1110_RX_HEADER_IS_METADATA BIT(14)
15#define SJA1110_RX_HEADER_HOST_ONLY BIT(13)
16#define SJA1110_RX_HEADER_HAS_TRAILER BIT(12)
17
18/* Trap-to-host format (no trailer present) */
19#define SJA1110_RX_HEADER_SRC_PORT(x) (((x) & GENMASK(7, 4)) >> 4)
20#define SJA1110_RX_HEADER_SWITCH_ID(x) ((x) & GENMASK(3, 0))
21
22/* Timestamp format (trailer present) */
23#define SJA1110_RX_HEADER_TRAILER_POS(x) ((x) & GENMASK(11, 0))
24
25#define SJA1110_RX_TRAILER_SWITCH_ID(x) (((x) & GENMASK(7, 4)) >> 4)
26#define SJA1110_RX_TRAILER_SRC_PORT(x) ((x) & GENMASK(3, 0))
27
28/* Meta frame format (for 2-step TX timestamps) */
29#define SJA1110_RX_HEADER_N_TS(x) (((x) & GENMASK(8, 4)) >> 4)
30
31/* TX header */
32#define SJA1110_TX_HEADER_UPDATE_TC BIT(14)
33#define SJA1110_TX_HEADER_TAKE_TS BIT(13)
34#define SJA1110_TX_HEADER_TAKE_TS_CASC BIT(12)
35#define SJA1110_TX_HEADER_HAS_TRAILER BIT(11)
36
37/* Only valid if SJA1110_TX_HEADER_HAS_TRAILER is false */
38#define SJA1110_TX_HEADER_PRIO(x) (((x) << 7) & GENMASK(10, 7))
39#define SJA1110_TX_HEADER_TSTAMP_ID(x) ((x) & GENMASK(7, 0))
40
41/* Only valid if SJA1110_TX_HEADER_HAS_TRAILER is true */
42#define SJA1110_TX_HEADER_TRAILER_POS(x) ((x) & GENMASK(10, 0))
43
44#define SJA1110_TX_TRAILER_TSTAMP_ID(x) (((x) << 24) & GENMASK(31, 24))
45#define SJA1110_TX_TRAILER_PRIO(x) (((x) << 21) & GENMASK(23, 21))
46#define SJA1110_TX_TRAILER_SWITCHID(x) (((x) << 12) & GENMASK(15, 12))
47#define SJA1110_TX_TRAILER_DESTPORTS(x) (((x) << 1) & GENMASK(11, 1))
48
49#define SJA1110_META_TSTAMP_SIZE 10
50
51#define SJA1110_HEADER_LEN 4
52#define SJA1110_RX_TRAILER_LEN 13
53#define SJA1110_TX_TRAILER_LEN 4
54#define SJA1110_MAX_PADDING_LEN 15
55
56/* Similar to is_link_local_ether_addr(hdr->h_dest) but also covers PTP */
57static inline bool sja1105_is_link_local(const struct sk_buff *skb)
58{
59 const struct ethhdr *hdr = eth_hdr(skb);
60 u64 dmac = ether_addr_to_u64(hdr->h_dest);
61
62 if (ntohs(hdr->h_proto) == ETH_P_SJA1105_META)
63 return false;
64 if ((dmac & SJA1105_LINKLOCAL_FILTER_A_MASK) ==
65 SJA1105_LINKLOCAL_FILTER_A)
66 return true;
67 if ((dmac & SJA1105_LINKLOCAL_FILTER_B_MASK) ==
68 SJA1105_LINKLOCAL_FILTER_B)
69 return true;
70 return false;
71}
72
73struct sja1105_meta {
74 u64 tstamp;
75 u64 dmac_byte_4;
76 u64 dmac_byte_3;
77 u64 source_port;
78 u64 switch_id;
79};
80
81static void sja1105_meta_unpack(const struct sk_buff *skb,
82 struct sja1105_meta *meta)
83{
84 u8 *buf = skb_mac_header(skb) + ETH_HLEN;
85
86 /* UM10944.pdf section 4.2.17 AVB Parameters:
87 * Structure of the meta-data follow-up frame.
88 * It is in network byte order, so there are no quirks
89 * while unpacking the meta frame.
90 *
91 * Also SJA1105 E/T only populates bits 23:0 of the timestamp
92 * whereas P/Q/R/S does 32 bits. Since the structure is the
93 * same and the E/T puts zeroes in the high-order byte, use
94 * a unified unpacking command for both device series.
95 */
96 packing(buf, &meta->tstamp, 31, 0, 4, UNPACK, 0);
97 packing(buf + 4, &meta->dmac_byte_4, 7, 0, 1, UNPACK, 0);
98 packing(buf + 5, &meta->dmac_byte_3, 7, 0, 1, UNPACK, 0);
99 packing(buf + 6, &meta->source_port, 7, 0, 1, UNPACK, 0);
100 packing(buf + 7, &meta->switch_id, 7, 0, 1, UNPACK, 0);
101}
102
103static inline bool sja1105_is_meta_frame(const struct sk_buff *skb)
104{
105 const struct ethhdr *hdr = eth_hdr(skb);
106 u64 smac = ether_addr_to_u64(hdr->h_source);
107 u64 dmac = ether_addr_to_u64(hdr->h_dest);
108
109 if (smac != SJA1105_META_SMAC)
110 return false;
111 if (dmac != SJA1105_META_DMAC)
112 return false;
113 if (ntohs(hdr->h_proto) != ETH_P_SJA1105_META)
114 return false;
115 return true;
116}
117
118static bool sja1105_can_use_vlan_as_tags(const struct sk_buff *skb)
119{
120 struct vlan_ethhdr *hdr = vlan_eth_hdr(skb);
121 u16 vlan_tci;
122
123 if (hdr->h_vlan_proto == htons(ETH_P_SJA1105))
124 return true;
125
126 if (hdr->h_vlan_proto != htons(ETH_P_8021Q) &&
127 !skb_vlan_tag_present(skb))
128 return false;
129
130 if (skb_vlan_tag_present(skb))
131 vlan_tci = skb_vlan_tag_get(skb);
132 else
133 vlan_tci = ntohs(hdr->h_vlan_TCI);
134
135 return vid_is_dsa_8021q(vlan_tci & VLAN_VID_MASK);
136}
137
138/* This is the first time the tagger sees the frame on RX.
139 * Figure out if we can decode it.
140 */
141static bool sja1105_filter(const struct sk_buff *skb, struct net_device *dev)
142{
143 if (sja1105_can_use_vlan_as_tags(skb))
144 return true;
145 if (sja1105_is_link_local(skb))
146 return true;
147 if (sja1105_is_meta_frame(skb))
148 return true;
149 return false;
150}
151
152/* Calls sja1105_port_deferred_xmit in sja1105_main.c */
153static struct sk_buff *sja1105_defer_xmit(struct sja1105_port *sp,
154 struct sk_buff *skb)
155{
156 /* Increase refcount so the kfree_skb in dsa_slave_xmit
157 * won't really free the packet.
158 */
159 skb_queue_tail(&sp->xmit_queue, skb_get(skb));
160 kthread_queue_work(sp->xmit_worker, &sp->xmit_work);
161
162 return NULL;
163}
164
165static u16 sja1105_xmit_tpid(struct sja1105_port *sp)
166{
167 return sp->xmit_tpid;
168}
169
170static struct sk_buff *sja1105_xmit(struct sk_buff *skb,
171 struct net_device *netdev)
172{
173 struct dsa_port *dp = dsa_slave_to_port(netdev);
174 u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index);
175 u16 queue_mapping = skb_get_queue_mapping(skb);
176 u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
177
178 /* Transmitting management traffic does not rely upon switch tagging,
179 * but instead SPI-installed management routes. Part 2 of this
180 * is the .port_deferred_xmit driver callback.
181 */
182 if (unlikely(sja1105_is_link_local(skb)))
183 return sja1105_defer_xmit(dp->priv, skb);
184
185 return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp->priv),
186 ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
187}
188
189static struct sk_buff *sja1110_xmit(struct sk_buff *skb,
190 struct net_device *netdev)
191{
192 struct sk_buff *clone = SJA1105_SKB_CB(skb)->clone;
193 struct dsa_port *dp = dsa_slave_to_port(netdev);
194 u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index);
195 u16 queue_mapping = skb_get_queue_mapping(skb);
196 u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
197 struct ethhdr *eth_hdr;
198 __be32 *tx_trailer;
199 __be16 *tx_header;
200 int trailer_pos;
201
202 /* Transmitting control packets is done using in-band control
203 * extensions, while data packets are transmitted using
204 * tag_8021q TX VLANs.
205 */
206 if (likely(!sja1105_is_link_local(skb)))
207 return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp->priv),
208 ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
209
210 skb_push(skb, SJA1110_HEADER_LEN);
211
212 /* Move Ethernet header to the left, making space for DSA tag */
213 memmove(skb->data, skb->data + SJA1110_HEADER_LEN, 2 * ETH_ALEN);
214
215 trailer_pos = skb->len;
216
217 /* On TX, skb->data points to skb_mac_header(skb) */
218 eth_hdr = (struct ethhdr *)skb->data;
219 tx_header = (__be16 *)(eth_hdr + 1);
220 tx_trailer = skb_put(skb, SJA1110_TX_TRAILER_LEN);
221
222 eth_hdr->h_proto = htons(ETH_P_SJA1110);
223
224 *tx_header = htons(SJA1110_HEADER_HOST_TO_SWITCH |
225 SJA1110_TX_HEADER_HAS_TRAILER |
226 SJA1110_TX_HEADER_TRAILER_POS(trailer_pos));
227 *tx_trailer = cpu_to_be32(SJA1110_TX_TRAILER_PRIO(pcp) |
228 SJA1110_TX_TRAILER_SWITCHID(dp->ds->index) |
229 SJA1110_TX_TRAILER_DESTPORTS(BIT(dp->index)));
230 if (clone) {
231 u8 ts_id = SJA1105_SKB_CB(clone)->ts_id;
232
233 *tx_header |= htons(SJA1110_TX_HEADER_TAKE_TS);
234 *tx_trailer |= cpu_to_be32(SJA1110_TX_TRAILER_TSTAMP_ID(ts_id));
235 }
236
237 return skb;
238}
239
240static void sja1105_transfer_meta(struct sk_buff *skb,
241 const struct sja1105_meta *meta)
242{
243 struct ethhdr *hdr = eth_hdr(skb);
244
245 hdr->h_dest[3] = meta->dmac_byte_3;
246 hdr->h_dest[4] = meta->dmac_byte_4;
247 SJA1105_SKB_CB(skb)->tstamp = meta->tstamp;
248}
249
250/* This is a simple state machine which follows the hardware mechanism of
251 * generating RX timestamps:
252 *
253 * After each timestampable skb (all traffic for which send_meta1 and
254 * send_meta0 is true, aka all MAC-filtered link-local traffic) a meta frame
255 * containing a partial timestamp is immediately generated by the switch and
256 * sent as a follow-up to the link-local frame on the CPU port.
257 *
258 * The meta frames have no unique identifier (such as sequence number) by which
259 * one may pair them to the correct timestampable frame.
260 * Instead, the switch has internal logic that ensures no frames are sent on
261 * the CPU port between a link-local timestampable frame and its corresponding
262 * meta follow-up. It also ensures strict ordering between ports (lower ports
263 * have higher priority towards the CPU port). For this reason, a per-port
264 * data structure is not needed/desirable.
265 *
266 * This function pairs the link-local frame with its partial timestamp from the
267 * meta follow-up frame. The full timestamp will be reconstructed later in a
268 * work queue.
269 */
270static struct sk_buff
271*sja1105_rcv_meta_state_machine(struct sk_buff *skb,
272 struct sja1105_meta *meta,
273 bool is_link_local,
274 bool is_meta)
275{
276 struct sja1105_port *sp;
277 struct dsa_port *dp;
278
279 dp = dsa_slave_to_port(skb->dev);
280 sp = dp->priv;
281
282 /* Step 1: A timestampable frame was received.
283 * Buffer it until we get its meta frame.
284 */
285 if (is_link_local) {
286 if (!test_bit(SJA1105_HWTS_RX_EN, &sp->data->state))
287 /* Do normal processing. */
288 return skb;
289
290 spin_lock(&sp->data->meta_lock);
291 /* Was this a link-local frame instead of the meta
292 * that we were expecting?
293 */
294 if (sp->data->stampable_skb) {
295 dev_err_ratelimited(dp->ds->dev,
296 "Expected meta frame, is %12llx "
297 "in the DSA master multicast filter?\n",
298 SJA1105_META_DMAC);
299 kfree_skb(sp->data->stampable_skb);
300 }
301
302 /* Hold a reference to avoid dsa_switch_rcv
303 * from freeing the skb.
304 */
305 sp->data->stampable_skb = skb_get(skb);
306 spin_unlock(&sp->data->meta_lock);
307
308 /* Tell DSA we got nothing */
309 return NULL;
310
311 /* Step 2: The meta frame arrived.
312 * Time to take the stampable skb out of the closet, annotate it
313 * with the partial timestamp, and pretend that we received it
314 * just now (basically masquerade the buffered frame as the meta
315 * frame, which serves no further purpose).
316 */
317 } else if (is_meta) {
318 struct sk_buff *stampable_skb;
319
320 /* Drop the meta frame if we're not in the right state
321 * to process it.
322 */
323 if (!test_bit(SJA1105_HWTS_RX_EN, &sp->data->state))
324 return NULL;
325
326 spin_lock(&sp->data->meta_lock);
327
328 stampable_skb = sp->data->stampable_skb;
329 sp->data->stampable_skb = NULL;
330
331 /* Was this a meta frame instead of the link-local
332 * that we were expecting?
333 */
334 if (!stampable_skb) {
335 dev_err_ratelimited(dp->ds->dev,
336 "Unexpected meta frame\n");
337 spin_unlock(&sp->data->meta_lock);
338 return NULL;
339 }
340
341 if (stampable_skb->dev != skb->dev) {
342 dev_err_ratelimited(dp->ds->dev,
343 "Meta frame on wrong port\n");
344 spin_unlock(&sp->data->meta_lock);
345 return NULL;
346 }
347
348 /* Free the meta frame and give DSA the buffered stampable_skb
349 * for further processing up the network stack.
350 */
351 kfree_skb(skb);
352 skb = stampable_skb;
353 sja1105_transfer_meta(skb, meta);
354
355 spin_unlock(&sp->data->meta_lock);
356 }
357
358 return skb;
359}
360
361static void sja1105_decode_subvlan(struct sk_buff *skb, u16 subvlan)
362{
363 struct dsa_port *dp = dsa_slave_to_port(skb->dev);
364 struct sja1105_port *sp = dp->priv;
365 u16 vid = sp->subvlan_map[subvlan];
366 u16 vlan_tci;
367
368 if (vid == VLAN_N_VID)
369 return;
370
371 vlan_tci = (skb->priority << VLAN_PRIO_SHIFT) | vid;
372 __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vlan_tci);
373}
374
375static bool sja1105_skb_has_tag_8021q(const struct sk_buff *skb)
376{
377 u16 tpid = ntohs(eth_hdr(skb)->h_proto);
378
379 return tpid == ETH_P_SJA1105 || tpid == ETH_P_8021Q ||
380 skb_vlan_tag_present(skb);
381}
382
383static bool sja1110_skb_has_inband_control_extension(const struct sk_buff *skb)
384{
385 return ntohs(eth_hdr(skb)->h_proto) == ETH_P_SJA1110;
386}
387
388static struct sk_buff *sja1105_rcv(struct sk_buff *skb,
389 struct net_device *netdev,
390 struct packet_type *pt)
391{
392 int source_port, switch_id, subvlan = 0;
393 struct sja1105_meta meta = {0};
394 struct ethhdr *hdr;
395 bool is_link_local;
396 bool is_meta;
397
398 hdr = eth_hdr(skb);
399 is_link_local = sja1105_is_link_local(skb);
400 is_meta = sja1105_is_meta_frame(skb);
401
402 skb->offload_fwd_mark = 1;
403
404 if (sja1105_skb_has_tag_8021q(skb)) {
405 /* Normal traffic path. */
406 dsa_8021q_rcv(skb, &source_port, &switch_id, &subvlan);
407 } else if (is_link_local) {
408 /* Management traffic path. Switch embeds the switch ID and
409 * port ID into bytes of the destination MAC, courtesy of
410 * the incl_srcpt options.
411 */
412 source_port = hdr->h_dest[3];
413 switch_id = hdr->h_dest[4];
414 /* Clear the DMAC bytes that were mangled by the switch */
415 hdr->h_dest[3] = 0;
416 hdr->h_dest[4] = 0;
417 } else if (is_meta) {
418 sja1105_meta_unpack(skb, &meta);
419 source_port = meta.source_port;
420 switch_id = meta.switch_id;
421 } else {
422 return NULL;
423 }
424
425 skb->dev = dsa_master_find_slave(netdev, switch_id, source_port);
426 if (!skb->dev) {
427 netdev_warn(netdev, "Couldn't decode source port\n");
428 return NULL;
429 }
430
431 if (subvlan)
432 sja1105_decode_subvlan(skb, subvlan);
433
434 return sja1105_rcv_meta_state_machine(skb, &meta, is_link_local,
435 is_meta);
436}
437
438static struct sk_buff *sja1110_rcv_meta(struct sk_buff *skb, u16 rx_header)
439{
440 int switch_id = SJA1110_RX_HEADER_SWITCH_ID(rx_header);
441 int n_ts = SJA1110_RX_HEADER_N_TS(rx_header);
442 struct net_device *master = skb->dev;
443 struct dsa_port *cpu_dp;
444 u8 *buf = skb->data + 2;
445 struct dsa_switch *ds;
446 int i;
447
448 cpu_dp = master->dsa_ptr;
449 ds = dsa_switch_find(cpu_dp->dst->index, switch_id);
450 if (!ds) {
451 net_err_ratelimited("%s: cannot find switch id %d\n",
452 master->name, switch_id);
453 return NULL;
454 }
455
456 for (i = 0; i <= n_ts; i++) {
457 u8 ts_id, source_port, dir;
458 u64 tstamp;
459
460 ts_id = buf[0];
461 source_port = (buf[1] & GENMASK(7, 4)) >> 4;
462 dir = (buf[1] & BIT(3)) >> 3;
463 tstamp = be64_to_cpu(*(__be64 *)(buf + 2));
464
465 sja1110_process_meta_tstamp(ds, source_port, ts_id, dir,
466 tstamp);
467
468 buf += SJA1110_META_TSTAMP_SIZE;
469 }
470
471 /* Discard the meta frame, we've consumed the timestamps it contained */
472 return NULL;
473}
474
475static struct sk_buff *sja1110_rcv_inband_control_extension(struct sk_buff *skb,
476 int *source_port,
477 int *switch_id)
478{
479 u16 rx_header;
480
481 if (unlikely(!pskb_may_pull(skb, SJA1110_HEADER_LEN)))
482 return NULL;
483
484 /* skb->data points to skb_mac_header(skb) + ETH_HLEN, which is exactly
485 * what we need because the caller has checked the EtherType (which is
486 * located 2 bytes back) and we just need a pointer to the header that
487 * comes afterwards.
488 */
489 rx_header = ntohs(*(__be16 *)skb->data);
490
491 if (rx_header & SJA1110_RX_HEADER_IS_METADATA)
492 return sja1110_rcv_meta(skb, rx_header);
493
494 /* Timestamp frame, we have a trailer */
495 if (rx_header & SJA1110_RX_HEADER_HAS_TRAILER) {
496 int start_of_padding = SJA1110_RX_HEADER_TRAILER_POS(rx_header);
497 u8 *rx_trailer = skb_tail_pointer(skb) - SJA1110_RX_TRAILER_LEN;
498 u64 *tstamp = &SJA1105_SKB_CB(skb)->tstamp;
499 u8 last_byte = rx_trailer[12];
500
501 /* The timestamp is unaligned, so we need to use packing()
502 * to get it
503 */
504 packing(rx_trailer, tstamp, 63, 0, 8, UNPACK, 0);
505
506 *source_port = SJA1110_RX_TRAILER_SRC_PORT(last_byte);
507 *switch_id = SJA1110_RX_TRAILER_SWITCH_ID(last_byte);
508
509 /* skb->len counts from skb->data, while start_of_padding
510 * counts from the destination MAC address. Right now skb->data
511 * is still as set by the DSA master, so to trim away the
512 * padding and trailer we need to account for the fact that
513 * skb->data points to skb_mac_header(skb) + ETH_HLEN.
514 */
515 pskb_trim_rcsum(skb, start_of_padding - ETH_HLEN);
516 /* Trap-to-host frame, no timestamp trailer */
517 } else {
518 *source_port = SJA1110_RX_HEADER_SRC_PORT(rx_header);
519 *switch_id = SJA1110_RX_HEADER_SWITCH_ID(rx_header);
520 }
521
522 /* Advance skb->data past the DSA header */
523 skb_pull_rcsum(skb, SJA1110_HEADER_LEN);
524
525 /* Remove the DSA header */
526 memmove(skb->data - ETH_HLEN, skb->data - ETH_HLEN - SJA1110_HEADER_LEN,
527 2 * ETH_ALEN);
528
529 /* With skb->data in its final place, update the MAC header
530 * so that eth_hdr() continues to works properly.
531 */
532 skb_set_mac_header(skb, -ETH_HLEN);
533
534 return skb;
535}
536
537static struct sk_buff *sja1110_rcv(struct sk_buff *skb,
538 struct net_device *netdev,
539 struct packet_type *pt)
540{
541 int source_port = -1, switch_id = -1, subvlan = 0;
542
543 skb->offload_fwd_mark = 1;
544
545 if (sja1110_skb_has_inband_control_extension(skb)) {
546 skb = sja1110_rcv_inband_control_extension(skb, &source_port,
547 &switch_id);
548 if (!skb)
549 return NULL;
550 }
551
552 /* Packets with in-band control extensions might still have RX VLANs */
553 if (likely(sja1105_skb_has_tag_8021q(skb)))
554 dsa_8021q_rcv(skb, &source_port, &switch_id, &subvlan);
555
556 skb->dev = dsa_master_find_slave(netdev, switch_id, source_port);
557 if (!skb->dev) {
558 netdev_warn(netdev,
559 "Couldn't decode source port %d and switch id %d\n",
560 source_port, switch_id);
561 return NULL;
562 }
563
564 if (subvlan)
565 sja1105_decode_subvlan(skb, subvlan);
566
567 return skb;
568}
569
570static void sja1105_flow_dissect(const struct sk_buff *skb, __be16 *proto,
571 int *offset)
572{
573 /* No tag added for management frames, all ok */
574 if (unlikely(sja1105_is_link_local(skb)))
575 return;
576
577 dsa_tag_generic_flow_dissect(skb, proto, offset);
578}
579
580static void sja1110_flow_dissect(const struct sk_buff *skb, __be16 *proto,
581 int *offset)
582{
583 /* Management frames have 2 DSA tags on RX, so the needed_headroom we
584 * declared is fine for the generic dissector adjustment procedure.
585 */
586 if (unlikely(sja1105_is_link_local(skb)))
587 return dsa_tag_generic_flow_dissect(skb, proto, offset);
588
589 /* For the rest, there is a single DSA tag, the tag_8021q one */
590 *offset = VLAN_HLEN;
591 *proto = ((__be16 *)skb->data)[(VLAN_HLEN / 2) - 1];
592}
593
594static const struct dsa_device_ops sja1105_netdev_ops = {
595 .name = "sja1105",
596 .proto = DSA_TAG_PROTO_SJA1105,
597 .xmit = sja1105_xmit,
598 .rcv = sja1105_rcv,
599 .filter = sja1105_filter,
600 .needed_headroom = VLAN_HLEN,
601 .flow_dissect = sja1105_flow_dissect,
602 .promisc_on_master = true,
603};
604
605DSA_TAG_DRIVER(sja1105_netdev_ops);
606MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1105);
607
608static const struct dsa_device_ops sja1110_netdev_ops = {
609 .name = "sja1110",
610 .proto = DSA_TAG_PROTO_SJA1110,
611 .xmit = sja1110_xmit,
612 .rcv = sja1110_rcv,
613 .filter = sja1105_filter,
614 .flow_dissect = sja1110_flow_dissect,
615 .needed_headroom = SJA1110_HEADER_LEN + VLAN_HLEN,
616 .needed_tailroom = SJA1110_RX_TRAILER_LEN + SJA1110_MAX_PADDING_LEN,
617};
618
619DSA_TAG_DRIVER(sja1110_netdev_ops);
620MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1110);
621
622static struct dsa_tag_driver *sja1105_tag_driver_array[] = {
623 &DSA_TAG_DRIVER_NAME(sja1105_netdev_ops),
624 &DSA_TAG_DRIVER_NAME(sja1110_netdev_ops),
625};
626
627module_dsa_tag_drivers(sja1105_tag_driver_array);
628
629MODULE_LICENSE("GPL v2");
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
61struct 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
71static struct sja1105_tagger_private *
72sja1105_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 */
78static 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
94struct 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
102static 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
124static 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 */
140static 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 */
174static 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
210static 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 */
240static 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
266static 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
293static 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
346static 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 */
376static 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
462static 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
470static 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
475static 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
526static 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
568static 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
633static 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
665static 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
675static 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
689static 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
698static 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
724static 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
736DSA_TAG_DRIVER(sja1105_netdev_ops);
737MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1105, SJA1105_NAME);
738
739static 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
751DSA_TAG_DRIVER(sja1110_netdev_ops);
752MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1110, SJA1110_NAME);
753
754static 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
759module_dsa_tag_drivers(sja1105_tag_driver_array);
760
761MODULE_DESCRIPTION("DSA tag driver for NXP SJA1105 switches");
762MODULE_LICENSE("GPL v2");