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/skbuff.h>
8 #include <linux/packing.h>
9 #include "dsa_priv.h"
10
11 /* Is this a TX or an RX header? */
12 #define SJA1110_HEADER_HOST_TO_SWITCH BIT(15)
13
14 /* RX header */
15 #define SJA1110_RX_HEADER_IS_METADATA BIT(14)
16 #define SJA1110_RX_HEADER_HOST_ONLY BIT(13)
17 #define SJA1110_RX_HEADER_HAS_TRAILER BIT(12)
18
19 /* Trap-to-host format (no trailer present) */
20 #define SJA1110_RX_HEADER_SRC_PORT(x) (((x) & GENMASK(7, 4)) >> 4)
21 #define SJA1110_RX_HEADER_SWITCH_ID(x) ((x) & GENMASK(3, 0))
22
23 /* Timestamp format (trailer present) */
24 #define SJA1110_RX_HEADER_TRAILER_POS(x) ((x) & GENMASK(11, 0))
25
26 #define SJA1110_RX_TRAILER_SWITCH_ID(x) (((x) & GENMASK(7, 4)) >> 4)
27 #define SJA1110_RX_TRAILER_SRC_PORT(x) ((x) & GENMASK(3, 0))
28
29 /* Meta frame format (for 2-step TX timestamps) */
30 #define SJA1110_RX_HEADER_N_TS(x) (((x) & GENMASK(8, 4)) >> 4)
31
32 /* TX header */
33 #define SJA1110_TX_HEADER_UPDATE_TC BIT(14)
34 #define SJA1110_TX_HEADER_TAKE_TS BIT(13)
35 #define SJA1110_TX_HEADER_TAKE_TS_CASC BIT(12)
36 #define SJA1110_TX_HEADER_HAS_TRAILER BIT(11)
37
38 /* Only valid if SJA1110_TX_HEADER_HAS_TRAILER is false */
39 #define SJA1110_TX_HEADER_PRIO(x) (((x) << 7) & GENMASK(10, 7))
40 #define SJA1110_TX_HEADER_TSTAMP_ID(x) ((x) & GENMASK(7, 0))
41
42 /* Only valid if SJA1110_TX_HEADER_HAS_TRAILER is true */
43 #define SJA1110_TX_HEADER_TRAILER_POS(x) ((x) & GENMASK(10, 0))
44
45 #define SJA1110_TX_TRAILER_TSTAMP_ID(x) (((x) << 24) & GENMASK(31, 24))
46 #define SJA1110_TX_TRAILER_PRIO(x) (((x) << 21) & GENMASK(23, 21))
47 #define SJA1110_TX_TRAILER_SWITCHID(x) (((x) << 12) & GENMASK(15, 12))
48 #define SJA1110_TX_TRAILER_DESTPORTS(x) (((x) << 1) & GENMASK(11, 1))
49
50 #define SJA1110_META_TSTAMP_SIZE 10
51
52 #define SJA1110_HEADER_LEN 4
53 #define SJA1110_RX_TRAILER_LEN 13
54 #define SJA1110_TX_TRAILER_LEN 4
55 #define SJA1110_MAX_PADDING_LEN 15
56
57 enum sja1110_meta_tstamp {
58 SJA1110_META_TSTAMP_TX = 0,
59 SJA1110_META_TSTAMP_RX = 1,
60 };
61
62 /* Similar to is_link_local_ether_addr(hdr->h_dest) but also covers PTP */
sja1105_is_link_local(const struct sk_buff * skb)63 static inline bool sja1105_is_link_local(const struct sk_buff *skb)
64 {
65 const struct ethhdr *hdr = eth_hdr(skb);
66 u64 dmac = ether_addr_to_u64(hdr->h_dest);
67
68 if (ntohs(hdr->h_proto) == ETH_P_SJA1105_META)
69 return false;
70 if ((dmac & SJA1105_LINKLOCAL_FILTER_A_MASK) ==
71 SJA1105_LINKLOCAL_FILTER_A)
72 return true;
73 if ((dmac & SJA1105_LINKLOCAL_FILTER_B_MASK) ==
74 SJA1105_LINKLOCAL_FILTER_B)
75 return true;
76 return false;
77 }
78
79 struct sja1105_meta {
80 u64 tstamp;
81 u64 dmac_byte_4;
82 u64 dmac_byte_3;
83 u64 source_port;
84 u64 switch_id;
85 };
86
sja1105_meta_unpack(const struct sk_buff * skb,struct sja1105_meta * meta)87 static void sja1105_meta_unpack(const struct sk_buff *skb,
88 struct sja1105_meta *meta)
89 {
90 u8 *buf = skb_mac_header(skb) + ETH_HLEN;
91
92 /* UM10944.pdf section 4.2.17 AVB Parameters:
93 * Structure of the meta-data follow-up frame.
94 * It is in network byte order, so there are no quirks
95 * while unpacking the meta frame.
96 *
97 * Also SJA1105 E/T only populates bits 23:0 of the timestamp
98 * whereas P/Q/R/S does 32 bits. Since the structure is the
99 * same and the E/T puts zeroes in the high-order byte, use
100 * a unified unpacking command for both device series.
101 */
102 packing(buf, &meta->tstamp, 31, 0, 4, UNPACK, 0);
103 packing(buf + 4, &meta->dmac_byte_3, 7, 0, 1, UNPACK, 0);
104 packing(buf + 5, &meta->dmac_byte_4, 7, 0, 1, UNPACK, 0);
105 packing(buf + 6, &meta->source_port, 7, 0, 1, UNPACK, 0);
106 packing(buf + 7, &meta->switch_id, 7, 0, 1, UNPACK, 0);
107 }
108
sja1105_is_meta_frame(const struct sk_buff * skb)109 static inline bool sja1105_is_meta_frame(const struct sk_buff *skb)
110 {
111 const struct ethhdr *hdr = eth_hdr(skb);
112 u64 smac = ether_addr_to_u64(hdr->h_source);
113 u64 dmac = ether_addr_to_u64(hdr->h_dest);
114
115 if (smac != SJA1105_META_SMAC)
116 return false;
117 if (dmac != SJA1105_META_DMAC)
118 return false;
119 if (ntohs(hdr->h_proto) != ETH_P_SJA1105_META)
120 return false;
121 return true;
122 }
123
124 /* Calls sja1105_port_deferred_xmit in sja1105_main.c */
sja1105_defer_xmit(struct dsa_port * dp,struct sk_buff * skb)125 static struct sk_buff *sja1105_defer_xmit(struct dsa_port *dp,
126 struct sk_buff *skb)
127 {
128 struct sja1105_port *sp = dp->priv;
129
130 if (!dsa_port_is_sja1105(dp))
131 return skb;
132
133 /* Increase refcount so the kfree_skb in dsa_slave_xmit
134 * won't really free the packet.
135 */
136 skb_queue_tail(&sp->xmit_queue, skb_get(skb));
137 kthread_queue_work(sp->xmit_worker, &sp->xmit_work);
138
139 return NULL;
140 }
141
142 /* Send VLAN tags with a TPID that blends in with whatever VLAN protocol a
143 * bridge spanning ports of this switch might have.
144 */
sja1105_xmit_tpid(struct dsa_port * dp)145 static u16 sja1105_xmit_tpid(struct dsa_port *dp)
146 {
147 struct dsa_switch *ds = dp->ds;
148 struct dsa_port *other_dp;
149 u16 proto;
150
151 /* Since VLAN awareness is global, then if this port is VLAN-unaware,
152 * all ports are. Use the VLAN-unaware TPID used for tag_8021q.
153 */
154 if (!dsa_port_is_vlan_filtering(dp))
155 return ETH_P_SJA1105;
156
157 /* Port is VLAN-aware, so there is a bridge somewhere (a single one,
158 * we're sure about that). It may not be on this port though, so we
159 * need to find it.
160 */
161 list_for_each_entry(other_dp, &ds->dst->ports, list) {
162 if (other_dp->ds != ds)
163 continue;
164
165 if (!other_dp->bridge_dev)
166 continue;
167
168 /* Error is returned only if CONFIG_BRIDGE_VLAN_FILTERING,
169 * which seems pointless to handle, as our port cannot become
170 * VLAN-aware in that case.
171 */
172 br_vlan_get_proto(other_dp->bridge_dev, &proto);
173
174 return proto;
175 }
176
177 WARN_ONCE(1, "Port is VLAN-aware but cannot find associated bridge!\n");
178
179 return ETH_P_SJA1105;
180 }
181
sja1105_imprecise_xmit(struct sk_buff * skb,struct net_device * netdev)182 static struct sk_buff *sja1105_imprecise_xmit(struct sk_buff *skb,
183 struct net_device *netdev)
184 {
185 struct dsa_port *dp = dsa_slave_to_port(netdev);
186 struct net_device *br = dp->bridge_dev;
187 u16 tx_vid;
188
189 /* If the port is under a VLAN-aware bridge, just slide the
190 * VLAN-tagged packet into the FDB and hope for the best.
191 * This works because we support a single VLAN-aware bridge
192 * across the entire dst, and its VLANs cannot be shared with
193 * any standalone port.
194 */
195 if (br_vlan_enabled(br))
196 return skb;
197
198 /* If the port is under a VLAN-unaware bridge, use an imprecise
199 * TX VLAN that targets the bridge's entire broadcast domain,
200 * instead of just the specific port.
201 */
202 tx_vid = dsa_8021q_bridge_tx_fwd_offload_vid(dp->bridge_num);
203
204 return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp), tx_vid);
205 }
206
207 /* Transform untagged control packets into pvid-tagged control packets so that
208 * all packets sent by this tagger are VLAN-tagged and we can configure the
209 * switch to drop untagged packets coming from the DSA master.
210 */
sja1105_pvid_tag_control_pkt(struct dsa_port * dp,struct sk_buff * skb,u8 pcp)211 static struct sk_buff *sja1105_pvid_tag_control_pkt(struct dsa_port *dp,
212 struct sk_buff *skb, u8 pcp)
213 {
214 __be16 xmit_tpid = htons(sja1105_xmit_tpid(dp));
215 struct vlan_ethhdr *hdr;
216
217 /* If VLAN tag is in hwaccel area, move it to the payload
218 * to deal with both cases uniformly and to ensure that
219 * the VLANs are added in the right order.
220 */
221 if (unlikely(skb_vlan_tag_present(skb))) {
222 skb = __vlan_hwaccel_push_inside(skb);
223 if (!skb)
224 return NULL;
225 }
226
227 hdr = (struct vlan_ethhdr *)skb_mac_header(skb);
228
229 /* If skb is already VLAN-tagged, leave that VLAN ID in place */
230 if (hdr->h_vlan_proto == xmit_tpid)
231 return skb;
232
233 return vlan_insert_tag(skb, xmit_tpid, (pcp << VLAN_PRIO_SHIFT) |
234 SJA1105_DEFAULT_VLAN);
235 }
236
sja1105_xmit(struct sk_buff * skb,struct net_device * netdev)237 static struct sk_buff *sja1105_xmit(struct sk_buff *skb,
238 struct net_device *netdev)
239 {
240 struct dsa_port *dp = dsa_slave_to_port(netdev);
241 u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index);
242 u16 queue_mapping = skb_get_queue_mapping(skb);
243 u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
244
245 if (skb->offload_fwd_mark)
246 return sja1105_imprecise_xmit(skb, netdev);
247
248 /* Transmitting management traffic does not rely upon switch tagging,
249 * but instead SPI-installed management routes. Part 2 of this
250 * is the .port_deferred_xmit driver callback.
251 */
252 if (unlikely(sja1105_is_link_local(skb))) {
253 skb = sja1105_pvid_tag_control_pkt(dp, skb, pcp);
254 if (!skb)
255 return NULL;
256
257 return sja1105_defer_xmit(dp, skb);
258 }
259
260 return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp),
261 ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
262 }
263
sja1110_xmit(struct sk_buff * skb,struct net_device * netdev)264 static struct sk_buff *sja1110_xmit(struct sk_buff *skb,
265 struct net_device *netdev)
266 {
267 struct sk_buff *clone = SJA1105_SKB_CB(skb)->clone;
268 struct dsa_port *dp = dsa_slave_to_port(netdev);
269 u16 tx_vid = dsa_8021q_tx_vid(dp->ds, dp->index);
270 u16 queue_mapping = skb_get_queue_mapping(skb);
271 u8 pcp = netdev_txq_to_tc(netdev, queue_mapping);
272 __be32 *tx_trailer;
273 __be16 *tx_header;
274 int trailer_pos;
275
276 if (skb->offload_fwd_mark)
277 return sja1105_imprecise_xmit(skb, netdev);
278
279 /* Transmitting control packets is done using in-band control
280 * extensions, while data packets are transmitted using
281 * tag_8021q TX VLANs.
282 */
283 if (likely(!sja1105_is_link_local(skb)))
284 return dsa_8021q_xmit(skb, netdev, sja1105_xmit_tpid(dp),
285 ((pcp << VLAN_PRIO_SHIFT) | tx_vid));
286
287 skb = sja1105_pvid_tag_control_pkt(dp, skb, pcp);
288 if (!skb)
289 return NULL;
290
291 skb_push(skb, SJA1110_HEADER_LEN);
292
293 dsa_alloc_etype_header(skb, SJA1110_HEADER_LEN);
294
295 trailer_pos = skb->len;
296
297 tx_header = dsa_etype_header_pos_tx(skb);
298 tx_trailer = skb_put(skb, SJA1110_TX_TRAILER_LEN);
299
300 tx_header[0] = htons(ETH_P_SJA1110);
301 tx_header[1] = htons(SJA1110_HEADER_HOST_TO_SWITCH |
302 SJA1110_TX_HEADER_HAS_TRAILER |
303 SJA1110_TX_HEADER_TRAILER_POS(trailer_pos));
304 *tx_trailer = cpu_to_be32(SJA1110_TX_TRAILER_PRIO(pcp) |
305 SJA1110_TX_TRAILER_SWITCHID(dp->ds->index) |
306 SJA1110_TX_TRAILER_DESTPORTS(BIT(dp->index)));
307 if (clone) {
308 u8 ts_id = SJA1105_SKB_CB(clone)->ts_id;
309
310 tx_header[1] |= htons(SJA1110_TX_HEADER_TAKE_TS);
311 *tx_trailer |= cpu_to_be32(SJA1110_TX_TRAILER_TSTAMP_ID(ts_id));
312 }
313
314 return skb;
315 }
316
sja1105_transfer_meta(struct sk_buff * skb,const struct sja1105_meta * meta)317 static void sja1105_transfer_meta(struct sk_buff *skb,
318 const struct sja1105_meta *meta)
319 {
320 struct ethhdr *hdr = eth_hdr(skb);
321
322 hdr->h_dest[3] = meta->dmac_byte_3;
323 hdr->h_dest[4] = meta->dmac_byte_4;
324 SJA1105_SKB_CB(skb)->tstamp = meta->tstamp;
325 }
326
327 /* This is a simple state machine which follows the hardware mechanism of
328 * generating RX timestamps:
329 *
330 * After each timestampable skb (all traffic for which send_meta1 and
331 * send_meta0 is true, aka all MAC-filtered link-local traffic) a meta frame
332 * containing a partial timestamp is immediately generated by the switch and
333 * sent as a follow-up to the link-local frame on the CPU port.
334 *
335 * The meta frames have no unique identifier (such as sequence number) by which
336 * one may pair them to the correct timestampable frame.
337 * Instead, the switch has internal logic that ensures no frames are sent on
338 * the CPU port between a link-local timestampable frame and its corresponding
339 * meta follow-up. It also ensures strict ordering between ports (lower ports
340 * have higher priority towards the CPU port). For this reason, a per-port
341 * data structure is not needed/desirable.
342 *
343 * This function pairs the link-local frame with its partial timestamp from the
344 * meta follow-up frame. The full timestamp will be reconstructed later in a
345 * work queue.
346 */
347 static struct sk_buff
sja1105_rcv_meta_state_machine(struct sk_buff * skb,struct sja1105_meta * meta,bool is_link_local,bool is_meta)348 *sja1105_rcv_meta_state_machine(struct sk_buff *skb,
349 struct sja1105_meta *meta,
350 bool is_link_local,
351 bool is_meta)
352 {
353 /* Step 1: A timestampable frame was received.
354 * Buffer it until we get its meta frame.
355 */
356 if (is_link_local) {
357 struct dsa_port *dp = dsa_slave_to_port(skb->dev);
358 struct sja1105_port *sp = dp->priv;
359
360 if (unlikely(!dsa_port_is_sja1105(dp)))
361 return skb;
362
363 if (!test_bit(SJA1105_HWTS_RX_EN, &sp->data->state))
364 /* Do normal processing. */
365 return skb;
366
367 spin_lock(&sp->data->meta_lock);
368 /* Was this a link-local frame instead of the meta
369 * that we were expecting?
370 */
371 if (sp->data->stampable_skb) {
372 dev_err_ratelimited(dp->ds->dev,
373 "Expected meta frame, is %12llx "
374 "in the DSA master multicast filter?\n",
375 SJA1105_META_DMAC);
376 kfree_skb(sp->data->stampable_skb);
377 }
378
379 /* Hold a reference to avoid dsa_switch_rcv
380 * from freeing the skb.
381 */
382 sp->data->stampable_skb = skb_get(skb);
383 spin_unlock(&sp->data->meta_lock);
384
385 /* Tell DSA we got nothing */
386 return NULL;
387
388 /* Step 2: The meta frame arrived.
389 * Time to take the stampable skb out of the closet, annotate it
390 * with the partial timestamp, and pretend that we received it
391 * just now (basically masquerade the buffered frame as the meta
392 * frame, which serves no further purpose).
393 */
394 } else if (is_meta) {
395 struct dsa_port *dp = dsa_slave_to_port(skb->dev);
396 struct sja1105_port *sp = dp->priv;
397 struct sk_buff *stampable_skb;
398
399 if (unlikely(!dsa_port_is_sja1105(dp)))
400 return skb;
401
402 /* Drop the meta frame if we're not in the right state
403 * to process it.
404 */
405 if (!test_bit(SJA1105_HWTS_RX_EN, &sp->data->state))
406 return NULL;
407
408 spin_lock(&sp->data->meta_lock);
409
410 stampable_skb = sp->data->stampable_skb;
411 sp->data->stampable_skb = NULL;
412
413 /* Was this a meta frame instead of the link-local
414 * that we were expecting?
415 */
416 if (!stampable_skb) {
417 dev_err_ratelimited(dp->ds->dev,
418 "Unexpected meta frame\n");
419 spin_unlock(&sp->data->meta_lock);
420 return NULL;
421 }
422
423 if (stampable_skb->dev != skb->dev) {
424 dev_err_ratelimited(dp->ds->dev,
425 "Meta frame on wrong port\n");
426 spin_unlock(&sp->data->meta_lock);
427 return NULL;
428 }
429
430 /* Free the meta frame and give DSA the buffered stampable_skb
431 * for further processing up the network stack.
432 */
433 kfree_skb(skb);
434 skb = stampable_skb;
435 sja1105_transfer_meta(skb, meta);
436
437 spin_unlock(&sp->data->meta_lock);
438 }
439
440 return skb;
441 }
442
sja1105_skb_has_tag_8021q(const struct sk_buff * skb)443 static bool sja1105_skb_has_tag_8021q(const struct sk_buff *skb)
444 {
445 u16 tpid = ntohs(eth_hdr(skb)->h_proto);
446
447 return tpid == ETH_P_SJA1105 || tpid == ETH_P_8021Q ||
448 skb_vlan_tag_present(skb);
449 }
450
sja1110_skb_has_inband_control_extension(const struct sk_buff * skb)451 static bool sja1110_skb_has_inband_control_extension(const struct sk_buff *skb)
452 {
453 return ntohs(eth_hdr(skb)->h_proto) == ETH_P_SJA1110;
454 }
455
456 /* If the VLAN in the packet is a tag_8021q one, set @source_port and
457 * @switch_id and strip the header. Otherwise set @vid and keep it in the
458 * packet.
459 */
sja1105_vlan_rcv(struct sk_buff * skb,int * source_port,int * switch_id,u16 * vid)460 static void sja1105_vlan_rcv(struct sk_buff *skb, int *source_port,
461 int *switch_id, u16 *vid)
462 {
463 struct vlan_ethhdr *hdr = (struct vlan_ethhdr *)skb_mac_header(skb);
464 u16 vlan_tci;
465
466 if (skb_vlan_tag_present(skb))
467 vlan_tci = skb_vlan_tag_get(skb);
468 else
469 vlan_tci = ntohs(hdr->h_vlan_TCI);
470
471 if (vid_is_dsa_8021q_rxvlan(vlan_tci & VLAN_VID_MASK))
472 return dsa_8021q_rcv(skb, source_port, switch_id);
473
474 /* Try our best with imprecise RX */
475 *vid = vlan_tci & VLAN_VID_MASK;
476 }
477
sja1105_rcv(struct sk_buff * skb,struct net_device * netdev)478 static struct sk_buff *sja1105_rcv(struct sk_buff *skb,
479 struct net_device *netdev)
480 {
481 int source_port = -1, switch_id = -1;
482 struct sja1105_meta meta = {0};
483 struct ethhdr *hdr;
484 bool is_link_local;
485 bool is_meta;
486 u16 vid;
487
488 hdr = eth_hdr(skb);
489 is_link_local = sja1105_is_link_local(skb);
490 is_meta = sja1105_is_meta_frame(skb);
491
492 if (sja1105_skb_has_tag_8021q(skb)) {
493 /* Normal traffic path. */
494 sja1105_vlan_rcv(skb, &source_port, &switch_id, &vid);
495 } else if (is_link_local) {
496 /* Management traffic path. Switch embeds the switch ID and
497 * port ID into bytes of the destination MAC, courtesy of
498 * the incl_srcpt options.
499 */
500 source_port = hdr->h_dest[3];
501 switch_id = hdr->h_dest[4];
502 /* Clear the DMAC bytes that were mangled by the switch */
503 hdr->h_dest[3] = 0;
504 hdr->h_dest[4] = 0;
505 } else if (is_meta) {
506 sja1105_meta_unpack(skb, &meta);
507 source_port = meta.source_port;
508 switch_id = meta.switch_id;
509 } else {
510 return NULL;
511 }
512
513 if (source_port == -1 || switch_id == -1)
514 skb->dev = dsa_find_designated_bridge_port_by_vid(netdev, vid);
515 else
516 skb->dev = dsa_master_find_slave(netdev, switch_id, source_port);
517 if (!skb->dev) {
518 netdev_warn(netdev, "Couldn't decode source port\n");
519 return NULL;
520 }
521
522 if (!is_link_local)
523 dsa_default_offload_fwd_mark(skb);
524
525 return sja1105_rcv_meta_state_machine(skb, &meta, is_link_local,
526 is_meta);
527 }
528
sja1110_process_meta_tstamp(struct dsa_switch * ds,int port,u8 ts_id,enum sja1110_meta_tstamp dir,u64 tstamp)529 static void sja1110_process_meta_tstamp(struct dsa_switch *ds, int port,
530 u8 ts_id, enum sja1110_meta_tstamp dir,
531 u64 tstamp)
532 {
533 struct sk_buff *skb, *skb_tmp, *skb_match = NULL;
534 struct dsa_port *dp = dsa_to_port(ds, port);
535 struct skb_shared_hwtstamps shwt = {0};
536 struct sja1105_port *sp = dp->priv;
537
538 if (!dsa_port_is_sja1105(dp))
539 return;
540
541 /* We don't care about RX timestamps on the CPU port */
542 if (dir == SJA1110_META_TSTAMP_RX)
543 return;
544
545 spin_lock(&sp->data->skb_txtstamp_queue.lock);
546
547 skb_queue_walk_safe(&sp->data->skb_txtstamp_queue, skb, skb_tmp) {
548 if (SJA1105_SKB_CB(skb)->ts_id != ts_id)
549 continue;
550
551 __skb_unlink(skb, &sp->data->skb_txtstamp_queue);
552 skb_match = skb;
553
554 break;
555 }
556
557 spin_unlock(&sp->data->skb_txtstamp_queue.lock);
558
559 if (WARN_ON(!skb_match))
560 return;
561
562 shwt.hwtstamp = ns_to_ktime(sja1105_ticks_to_ns(tstamp));
563 skb_complete_tx_timestamp(skb_match, &shwt);
564 }
565
sja1110_rcv_meta(struct sk_buff * skb,u16 rx_header)566 static struct sk_buff *sja1110_rcv_meta(struct sk_buff *skb, u16 rx_header)
567 {
568 u8 *buf = dsa_etype_header_pos_rx(skb) + SJA1110_HEADER_LEN;
569 int switch_id = SJA1110_RX_HEADER_SWITCH_ID(rx_header);
570 int n_ts = SJA1110_RX_HEADER_N_TS(rx_header);
571 struct net_device *master = skb->dev;
572 struct dsa_port *cpu_dp;
573 struct dsa_switch *ds;
574 int i;
575
576 cpu_dp = master->dsa_ptr;
577 ds = dsa_switch_find(cpu_dp->dst->index, switch_id);
578 if (!ds) {
579 net_err_ratelimited("%s: cannot find switch id %d\n",
580 master->name, switch_id);
581 return NULL;
582 }
583
584 for (i = 0; i <= n_ts; i++) {
585 u8 ts_id, source_port, dir;
586 u64 tstamp;
587
588 ts_id = buf[0];
589 source_port = (buf[1] & GENMASK(7, 4)) >> 4;
590 dir = (buf[1] & BIT(3)) >> 3;
591 tstamp = be64_to_cpu(*(__be64 *)(buf + 2));
592
593 sja1110_process_meta_tstamp(ds, source_port, ts_id, dir,
594 tstamp);
595
596 buf += SJA1110_META_TSTAMP_SIZE;
597 }
598
599 /* Discard the meta frame, we've consumed the timestamps it contained */
600 return NULL;
601 }
602
sja1110_rcv_inband_control_extension(struct sk_buff * skb,int * source_port,int * switch_id,bool * host_only)603 static struct sk_buff *sja1110_rcv_inband_control_extension(struct sk_buff *skb,
604 int *source_port,
605 int *switch_id,
606 bool *host_only)
607 {
608 u16 rx_header;
609
610 if (unlikely(!pskb_may_pull(skb, SJA1110_HEADER_LEN)))
611 return NULL;
612
613 /* skb->data points to skb_mac_header(skb) + ETH_HLEN, which is exactly
614 * what we need because the caller has checked the EtherType (which is
615 * located 2 bytes back) and we just need a pointer to the header that
616 * comes afterwards.
617 */
618 rx_header = ntohs(*(__be16 *)skb->data);
619
620 if (rx_header & SJA1110_RX_HEADER_HOST_ONLY)
621 *host_only = true;
622
623 if (rx_header & SJA1110_RX_HEADER_IS_METADATA)
624 return sja1110_rcv_meta(skb, rx_header);
625
626 /* Timestamp frame, we have a trailer */
627 if (rx_header & SJA1110_RX_HEADER_HAS_TRAILER) {
628 int start_of_padding = SJA1110_RX_HEADER_TRAILER_POS(rx_header);
629 u8 *rx_trailer = skb_tail_pointer(skb) - SJA1110_RX_TRAILER_LEN;
630 u64 *tstamp = &SJA1105_SKB_CB(skb)->tstamp;
631 u8 last_byte = rx_trailer[12];
632
633 /* The timestamp is unaligned, so we need to use packing()
634 * to get it
635 */
636 packing(rx_trailer, tstamp, 63, 0, 8, UNPACK, 0);
637
638 *source_port = SJA1110_RX_TRAILER_SRC_PORT(last_byte);
639 *switch_id = SJA1110_RX_TRAILER_SWITCH_ID(last_byte);
640
641 /* skb->len counts from skb->data, while start_of_padding
642 * counts from the destination MAC address. Right now skb->data
643 * is still as set by the DSA master, so to trim away the
644 * padding and trailer we need to account for the fact that
645 * skb->data points to skb_mac_header(skb) + ETH_HLEN.
646 */
647 if (pskb_trim_rcsum(skb, start_of_padding - ETH_HLEN))
648 return NULL;
649 /* Trap-to-host frame, no timestamp trailer */
650 } else {
651 *source_port = SJA1110_RX_HEADER_SRC_PORT(rx_header);
652 *switch_id = SJA1110_RX_HEADER_SWITCH_ID(rx_header);
653 }
654
655 /* Advance skb->data past the DSA header */
656 skb_pull_rcsum(skb, SJA1110_HEADER_LEN);
657
658 dsa_strip_etype_header(skb, SJA1110_HEADER_LEN);
659
660 /* With skb->data in its final place, update the MAC header
661 * so that eth_hdr() continues to works properly.
662 */
663 skb_set_mac_header(skb, -ETH_HLEN);
664
665 return skb;
666 }
667
sja1110_rcv(struct sk_buff * skb,struct net_device * netdev)668 static struct sk_buff *sja1110_rcv(struct sk_buff *skb,
669 struct net_device *netdev)
670 {
671 int source_port = -1, switch_id = -1;
672 bool host_only = false;
673 u16 vid = 0;
674
675 if (sja1110_skb_has_inband_control_extension(skb)) {
676 skb = sja1110_rcv_inband_control_extension(skb, &source_port,
677 &switch_id,
678 &host_only);
679 if (!skb)
680 return NULL;
681 }
682
683 /* Packets with in-band control extensions might still have RX VLANs */
684 if (likely(sja1105_skb_has_tag_8021q(skb)))
685 sja1105_vlan_rcv(skb, &source_port, &switch_id, &vid);
686
687 if (source_port == -1 || switch_id == -1)
688 skb->dev = dsa_find_designated_bridge_port_by_vid(netdev, vid);
689 else
690 skb->dev = dsa_master_find_slave(netdev, switch_id, source_port);
691 if (!skb->dev) {
692 netdev_warn(netdev, "Couldn't decode source port\n");
693 return NULL;
694 }
695
696 if (!host_only)
697 dsa_default_offload_fwd_mark(skb);
698
699 return skb;
700 }
701
sja1105_flow_dissect(const struct sk_buff * skb,__be16 * proto,int * offset)702 static void sja1105_flow_dissect(const struct sk_buff *skb, __be16 *proto,
703 int *offset)
704 {
705 /* No tag added for management frames, all ok */
706 if (unlikely(sja1105_is_link_local(skb)))
707 return;
708
709 dsa_tag_generic_flow_dissect(skb, proto, offset);
710 }
711
sja1110_flow_dissect(const struct sk_buff * skb,__be16 * proto,int * offset)712 static void sja1110_flow_dissect(const struct sk_buff *skb, __be16 *proto,
713 int *offset)
714 {
715 /* Management frames have 2 DSA tags on RX, so the needed_headroom we
716 * declared is fine for the generic dissector adjustment procedure.
717 */
718 if (unlikely(sja1105_is_link_local(skb)))
719 return dsa_tag_generic_flow_dissect(skb, proto, offset);
720
721 /* For the rest, there is a single DSA tag, the tag_8021q one */
722 *offset = VLAN_HLEN;
723 *proto = ((__be16 *)skb->data)[(VLAN_HLEN / 2) - 1];
724 }
725
726 static const struct dsa_device_ops sja1105_netdev_ops = {
727 .name = "sja1105",
728 .proto = DSA_TAG_PROTO_SJA1105,
729 .xmit = sja1105_xmit,
730 .rcv = sja1105_rcv,
731 .needed_headroom = VLAN_HLEN,
732 .flow_dissect = sja1105_flow_dissect,
733 .promisc_on_master = true,
734 };
735
736 DSA_TAG_DRIVER(sja1105_netdev_ops);
737 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1105);
738
739 static const struct dsa_device_ops sja1110_netdev_ops = {
740 .name = "sja1110",
741 .proto = DSA_TAG_PROTO_SJA1110,
742 .xmit = sja1110_xmit,
743 .rcv = sja1110_rcv,
744 .flow_dissect = sja1110_flow_dissect,
745 .needed_headroom = SJA1110_HEADER_LEN + VLAN_HLEN,
746 .needed_tailroom = SJA1110_RX_TRAILER_LEN + SJA1110_MAX_PADDING_LEN,
747 };
748
749 DSA_TAG_DRIVER(sja1110_netdev_ops);
750 MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1110);
751
752 static struct dsa_tag_driver *sja1105_tag_driver_array[] = {
753 &DSA_TAG_DRIVER_NAME(sja1105_netdev_ops),
754 &DSA_TAG_DRIVER_NAME(sja1110_netdev_ops),
755 };
756
757 module_dsa_tag_drivers(sja1105_tag_driver_array);
758
759 MODULE_LICENSE("GPL v2");
760