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(addr: 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(pbuf: buf, uval: &meta->tstamp, startbit: 31, endbit: 0, pbuflen: 4, op: UNPACK, quirks: 0);
118 packing(pbuf: buf + 4, uval: &meta->dmac_byte_3, startbit: 7, endbit: 0, pbuflen: 1, op: UNPACK, quirks: 0);
119 packing(pbuf: buf + 5, uval: &meta->dmac_byte_4, startbit: 7, endbit: 0, pbuflen: 1, op: UNPACK, quirks: 0);
120 packing(pbuf: buf + 6, uval: &meta->source_port, startbit: 7, endbit: 0, pbuflen: 1, op: UNPACK, quirks: 0);
121 packing(pbuf: buf + 7, uval: &meta->switch_id, startbit: 7, endbit: 0, pbuflen: 1, op: UNPACK, quirks: 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(addr: hdr->h_source);
128 u64 dmac = ether_addr_to_u64(addr: 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(ds: dp->ds);
144 struct sja1105_tagger_private *priv = sja1105_tagger_private(ds: 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(size: 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(worker: xmit_worker, work: &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(dp: 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(dev: br, p_proto: &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(dev: 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(dev: 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, tpid: sja1105_xmit_tpid(dp), tci: 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, vlan_proto: xmit_tpid, vlan_tci: (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(dev: netdev);
270 u16 queue_mapping = skb_get_queue_mapping(skb);
271 u8 pcp = netdev_txq_to_tc(dev: netdev, txq: 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, tpid: sja1105_xmit_tpid(dp),
290 tci: ((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(dev: netdev);
298 u16 queue_mapping = skb_get_queue_mapping(skb);
299 u8 pcp = netdev_txq_to_tc(dev: netdev, txq: 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, tpid: sja1105_xmit_tpid(dp),
314 tci: ((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(dev: 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(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(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(lock: &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(dev: 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(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(lock: &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(lock: &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(lock: &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
475/* If the VLAN in the packet is a tag_8021q one, set @source_port and
476 * @switch_id and strip the header. Otherwise set @vid and keep it in the
477 * packet.
478 */
479static void sja1105_vlan_rcv(struct sk_buff *skb, int *source_port,
480 int *switch_id, int *vbid, u16 *vid)
481{
482 struct vlan_ethhdr *hdr = vlan_eth_hdr(skb);
483 u16 vlan_tci;
484
485 if (skb_vlan_tag_present(skb))
486 vlan_tci = skb_vlan_tag_get(skb);
487 else
488 vlan_tci = ntohs(hdr->h_vlan_TCI);
489
490 if (vid_is_dsa_8021q(vid: vlan_tci & VLAN_VID_MASK))
491 return dsa_8021q_rcv(skb, source_port, switch_id, vbid);
492
493 /* Try our best with imprecise RX */
494 *vid = vlan_tci & VLAN_VID_MASK;
495}
496
497static struct sk_buff *sja1105_rcv(struct sk_buff *skb,
498 struct net_device *netdev)
499{
500 int source_port = -1, switch_id = -1, vbid = -1;
501 struct sja1105_meta meta = {0};
502 struct ethhdr *hdr;
503 bool is_link_local;
504 bool is_meta;
505 u16 vid;
506
507 hdr = eth_hdr(skb);
508 is_link_local = sja1105_is_link_local(skb);
509 is_meta = sja1105_is_meta_frame(skb);
510
511 if (is_link_local) {
512 /* Management traffic path. Switch embeds the switch ID and
513 * port ID into bytes of the destination MAC, courtesy of
514 * the incl_srcpt options.
515 */
516 source_port = hdr->h_dest[3];
517 switch_id = hdr->h_dest[4];
518 } else if (is_meta) {
519 sja1105_meta_unpack(skb, meta: &meta);
520 source_port = meta.source_port;
521 switch_id = meta.switch_id;
522 }
523
524 /* Normal data plane traffic and link-local frames are tagged with
525 * a tag_8021q VLAN which we have to strip
526 */
527 if (sja1105_skb_has_tag_8021q(skb)) {
528 int tmp_source_port = -1, tmp_switch_id = -1;
529
530 sja1105_vlan_rcv(skb, source_port: &tmp_source_port, switch_id: &tmp_switch_id, vbid: &vbid,
531 vid: &vid);
532 /* Preserve the source information from the INCL_SRCPT option,
533 * if available. This allows us to not overwrite a valid source
534 * port and switch ID with zeroes when receiving link-local
535 * frames from a VLAN-unaware bridged port (non-zero vbid) or a
536 * VLAN-aware bridged port (non-zero vid). Furthermore, the
537 * tag_8021q source port information is only of trust when the
538 * vbid is 0 (precise port). Otherwise, tmp_source_port and
539 * tmp_switch_id will be zeroes.
540 */
541 if (vbid == 0 && source_port == -1)
542 source_port = tmp_source_port;
543 if (vbid == 0 && switch_id == -1)
544 switch_id = tmp_switch_id;
545 } else if (source_port == -1 && switch_id == -1) {
546 /* Packets with no source information have no chance of
547 * getting accepted, drop them straight away.
548 */
549 return NULL;
550 }
551
552 if (source_port != -1 && switch_id != -1)
553 skb->dev = dsa_conduit_find_user(dev: netdev, device: switch_id, port: source_port);
554 else if (vbid >= 1)
555 skb->dev = dsa_tag_8021q_find_port_by_vbid(conduit: netdev, vbid);
556 else
557 skb->dev = dsa_find_designated_bridge_port_by_vid(conduit: netdev, vid);
558 if (!skb->dev) {
559 netdev_warn(dev: netdev, format: "Couldn't decode source port\n");
560 return NULL;
561 }
562
563 if (!is_link_local)
564 dsa_default_offload_fwd_mark(skb);
565
566 return sja1105_rcv_meta_state_machine(skb, meta: &meta, is_link_local,
567 is_meta);
568}
569
570static struct sk_buff *sja1110_rcv_meta(struct sk_buff *skb, u16 rx_header)
571{
572 u8 *buf = dsa_etype_header_pos_rx(skb) + SJA1110_HEADER_LEN;
573 int switch_id = SJA1110_RX_HEADER_SWITCH_ID(rx_header);
574 int n_ts = SJA1110_RX_HEADER_N_TS(rx_header);
575 struct sja1105_tagger_data *tagger_data;
576 struct net_device *conduit = skb->dev;
577 struct dsa_port *cpu_dp;
578 struct dsa_switch *ds;
579 int i;
580
581 cpu_dp = conduit->dsa_ptr;
582 ds = dsa_switch_find(tree_index: cpu_dp->dst->index, sw_index: switch_id);
583 if (!ds) {
584 net_err_ratelimited("%s: cannot find switch id %d\n",
585 conduit->name, switch_id);
586 return NULL;
587 }
588
589 tagger_data = sja1105_tagger_data(ds);
590 if (!tagger_data->meta_tstamp_handler)
591 return NULL;
592
593 for (i = 0; i <= n_ts; i++) {
594 u8 ts_id, source_port, dir;
595 u64 tstamp;
596
597 ts_id = buf[0];
598 source_port = (buf[1] & GENMASK(7, 4)) >> 4;
599 dir = (buf[1] & BIT(3)) >> 3;
600 tstamp = be64_to_cpu(*(__be64 *)(buf + 2));
601
602 tagger_data->meta_tstamp_handler(ds, source_port, ts_id, dir,
603 tstamp);
604
605 buf += SJA1110_META_TSTAMP_SIZE;
606 }
607
608 /* Discard the meta frame, we've consumed the timestamps it contained */
609 return NULL;
610}
611
612static struct sk_buff *sja1110_rcv_inband_control_extension(struct sk_buff *skb,
613 int *source_port,
614 int *switch_id,
615 bool *host_only)
616{
617 u16 rx_header;
618
619 if (unlikely(!pskb_may_pull(skb, SJA1110_HEADER_LEN)))
620 return NULL;
621
622 /* skb->data points to skb_mac_header(skb) + ETH_HLEN, which is exactly
623 * what we need because the caller has checked the EtherType (which is
624 * located 2 bytes back) and we just need a pointer to the header that
625 * comes afterwards.
626 */
627 rx_header = ntohs(*(__be16 *)skb->data);
628
629 if (rx_header & SJA1110_RX_HEADER_HOST_ONLY)
630 *host_only = true;
631
632 if (rx_header & SJA1110_RX_HEADER_IS_METADATA)
633 return sja1110_rcv_meta(skb, rx_header);
634
635 /* Timestamp frame, we have a trailer */
636 if (rx_header & SJA1110_RX_HEADER_HAS_TRAILER) {
637 int start_of_padding = SJA1110_RX_HEADER_TRAILER_POS(rx_header);
638 u8 *rx_trailer = skb_tail_pointer(skb) - SJA1110_RX_TRAILER_LEN;
639 u64 *tstamp = &SJA1105_SKB_CB(skb)->tstamp;
640 u8 last_byte = rx_trailer[12];
641
642 /* The timestamp is unaligned, so we need to use packing()
643 * to get it
644 */
645 packing(pbuf: rx_trailer, uval: tstamp, startbit: 63, endbit: 0, pbuflen: 8, op: UNPACK, quirks: 0);
646
647 *source_port = SJA1110_RX_TRAILER_SRC_PORT(last_byte);
648 *switch_id = SJA1110_RX_TRAILER_SWITCH_ID(last_byte);
649
650 /* skb->len counts from skb->data, while start_of_padding
651 * counts from the destination MAC address. Right now skb->data
652 * is still as set by the DSA conduit, so to trim away the
653 * padding and trailer we need to account for the fact that
654 * skb->data points to skb_mac_header(skb) + ETH_HLEN.
655 */
656 if (pskb_trim_rcsum(skb, len: start_of_padding - ETH_HLEN))
657 return NULL;
658 /* Trap-to-host frame, no timestamp trailer */
659 } else {
660 *source_port = SJA1110_RX_HEADER_SRC_PORT(rx_header);
661 *switch_id = SJA1110_RX_HEADER_SWITCH_ID(rx_header);
662 }
663
664 /* Advance skb->data past the DSA header */
665 skb_pull_rcsum(skb, SJA1110_HEADER_LEN);
666
667 dsa_strip_etype_header(skb, SJA1110_HEADER_LEN);
668
669 /* With skb->data in its final place, update the MAC header
670 * so that eth_hdr() continues to works properly.
671 */
672 skb_set_mac_header(skb, offset: -ETH_HLEN);
673
674 return skb;
675}
676
677static struct sk_buff *sja1110_rcv(struct sk_buff *skb,
678 struct net_device *netdev)
679{
680 int source_port = -1, switch_id = -1, vbid = -1;
681 bool host_only = false;
682 u16 vid = 0;
683
684 if (sja1110_skb_has_inband_control_extension(skb)) {
685 skb = sja1110_rcv_inband_control_extension(skb, source_port: &source_port,
686 switch_id: &switch_id,
687 host_only: &host_only);
688 if (!skb)
689 return NULL;
690 }
691
692 /* Packets with in-band control extensions might still have RX VLANs */
693 if (likely(sja1105_skb_has_tag_8021q(skb)))
694 sja1105_vlan_rcv(skb, source_port: &source_port, switch_id: &switch_id, vbid: &vbid, vid: &vid);
695
696 if (vbid >= 1)
697 skb->dev = dsa_tag_8021q_find_port_by_vbid(conduit: netdev, vbid);
698 else if (source_port == -1 || switch_id == -1)
699 skb->dev = dsa_find_designated_bridge_port_by_vid(conduit: netdev, vid);
700 else
701 skb->dev = dsa_conduit_find_user(dev: netdev, device: switch_id, port: source_port);
702 if (!skb->dev) {
703 netdev_warn(dev: netdev, format: "Couldn't decode source port\n");
704 return NULL;
705 }
706
707 if (!host_only)
708 dsa_default_offload_fwd_mark(skb);
709
710 return skb;
711}
712
713static void sja1105_flow_dissect(const struct sk_buff *skb, __be16 *proto,
714 int *offset)
715{
716 /* No tag added for management frames, all ok */
717 if (unlikely(sja1105_is_link_local(skb)))
718 return;
719
720 dsa_tag_generic_flow_dissect(skb, proto, offset);
721}
722
723static void sja1110_flow_dissect(const struct sk_buff *skb, __be16 *proto,
724 int *offset)
725{
726 /* Management frames have 2 DSA tags on RX, so the needed_headroom we
727 * declared is fine for the generic dissector adjustment procedure.
728 */
729 if (unlikely(sja1105_is_link_local(skb)))
730 return dsa_tag_generic_flow_dissect(skb, proto, offset);
731
732 /* For the rest, there is a single DSA tag, the tag_8021q one */
733 *offset = VLAN_HLEN;
734 *proto = ((__be16 *)skb->data)[(VLAN_HLEN / 2) - 1];
735}
736
737static void sja1105_disconnect(struct dsa_switch *ds)
738{
739 struct sja1105_tagger_private *priv = ds->tagger_data;
740
741 kthread_destroy_worker(worker: priv->xmit_worker);
742 kfree(objp: priv);
743 ds->tagger_data = NULL;
744}
745
746static int sja1105_connect(struct dsa_switch *ds)
747{
748 struct sja1105_tagger_private *priv;
749 struct kthread_worker *xmit_worker;
750 int err;
751
752 priv = kzalloc(size: sizeof(*priv), GFP_KERNEL);
753 if (!priv)
754 return -ENOMEM;
755
756 spin_lock_init(&priv->meta_lock);
757
758 xmit_worker = kthread_create_worker(flags: 0, namefmt: "dsa%d:%d_xmit",
759 ds->dst->index, ds->index);
760 if (IS_ERR(ptr: xmit_worker)) {
761 err = PTR_ERR(ptr: xmit_worker);
762 kfree(objp: priv);
763 return err;
764 }
765
766 priv->xmit_worker = xmit_worker;
767 ds->tagger_data = priv;
768
769 return 0;
770}
771
772static const struct dsa_device_ops sja1105_netdev_ops = {
773 .name = SJA1105_NAME,
774 .proto = DSA_TAG_PROTO_SJA1105,
775 .xmit = sja1105_xmit,
776 .rcv = sja1105_rcv,
777 .connect = sja1105_connect,
778 .disconnect = sja1105_disconnect,
779 .needed_headroom = VLAN_HLEN,
780 .flow_dissect = sja1105_flow_dissect,
781 .promisc_on_conduit = true,
782};
783
784DSA_TAG_DRIVER(sja1105_netdev_ops);
785MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1105, SJA1105_NAME);
786
787static const struct dsa_device_ops sja1110_netdev_ops = {
788 .name = SJA1110_NAME,
789 .proto = DSA_TAG_PROTO_SJA1110,
790 .xmit = sja1110_xmit,
791 .rcv = sja1110_rcv,
792 .connect = sja1105_connect,
793 .disconnect = sja1105_disconnect,
794 .flow_dissect = sja1110_flow_dissect,
795 .needed_headroom = SJA1110_HEADER_LEN + VLAN_HLEN,
796 .needed_tailroom = SJA1110_RX_TRAILER_LEN + SJA1110_MAX_PADDING_LEN,
797};
798
799DSA_TAG_DRIVER(sja1110_netdev_ops);
800MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_SJA1110, SJA1110_NAME);
801
802static struct dsa_tag_driver *sja1105_tag_driver_array[] = {
803 &DSA_TAG_DRIVER_NAME(sja1105_netdev_ops),
804 &DSA_TAG_DRIVER_NAME(sja1110_netdev_ops),
805};
806
807module_dsa_tag_drivers(sja1105_tag_driver_array);
808
809MODULE_DESCRIPTION("DSA tag driver for NXP SJA1105 switches");
810MODULE_LICENSE("GPL v2");
811

source code of linux/net/dsa/tag_sja1105.c