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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");