1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * net/dsa/tag_ksz.c - Microchip KSZ Switch tag format handling
4 * Copyright (c) 2017 Microchip Technology
5 */
6
7#include <linux/dsa/ksz_common.h>
8#include <linux/etherdevice.h>
9#include <linux/list.h>
10#include <linux/ptp_classify.h>
11#include <net/dsa.h>
12
13#include "tag.h"
14
15#define KSZ8795_NAME "ksz8795"
16#define KSZ9477_NAME "ksz9477"
17#define KSZ9893_NAME "ksz9893"
18#define LAN937X_NAME "lan937x"
19
20/* Typically only one byte is used for tail tag. */
21#define KSZ_PTP_TAG_LEN 4
22#define KSZ_EGRESS_TAG_LEN 1
23#define KSZ_INGRESS_TAG_LEN 1
24
25#define KSZ_HWTS_EN 0
26
27struct ksz_tagger_private {
28 struct ksz_tagger_data data; /* Must be first */
29 unsigned long state;
30 struct kthread_worker *xmit_worker;
31};
32
33static struct ksz_tagger_private *
34ksz_tagger_private(struct dsa_switch *ds)
35{
36 return ds->tagger_data;
37}
38
39static void ksz_hwtstamp_set_state(struct dsa_switch *ds, bool on)
40{
41 struct ksz_tagger_private *priv = ksz_tagger_private(ds);
42
43 if (on)
44 set_bit(KSZ_HWTS_EN, addr: &priv->state);
45 else
46 clear_bit(KSZ_HWTS_EN, addr: &priv->state);
47}
48
49static void ksz_disconnect(struct dsa_switch *ds)
50{
51 struct ksz_tagger_private *priv = ds->tagger_data;
52
53 kthread_destroy_worker(worker: priv->xmit_worker);
54 kfree(objp: priv);
55 ds->tagger_data = NULL;
56}
57
58static int ksz_connect(struct dsa_switch *ds)
59{
60 struct ksz_tagger_data *tagger_data;
61 struct kthread_worker *xmit_worker;
62 struct ksz_tagger_private *priv;
63 int ret;
64
65 priv = kzalloc(size: sizeof(*priv), GFP_KERNEL);
66 if (!priv)
67 return -ENOMEM;
68
69 xmit_worker = kthread_create_worker(flags: 0, namefmt: "dsa%d:%d_xmit",
70 ds->dst->index, ds->index);
71 if (IS_ERR(ptr: xmit_worker)) {
72 ret = PTR_ERR(ptr: xmit_worker);
73 kfree(objp: priv);
74 return ret;
75 }
76
77 priv->xmit_worker = xmit_worker;
78 /* Export functions for switch driver use */
79 tagger_data = &priv->data;
80 tagger_data->hwtstamp_set_state = ksz_hwtstamp_set_state;
81 ds->tagger_data = priv;
82
83 return 0;
84}
85
86static struct sk_buff *ksz_common_rcv(struct sk_buff *skb,
87 struct net_device *dev,
88 unsigned int port, unsigned int len)
89{
90 skb->dev = dsa_conduit_find_user(dev, device: 0, port);
91 if (!skb->dev)
92 return NULL;
93
94 if (pskb_trim_rcsum(skb, len: skb->len - len))
95 return NULL;
96
97 dsa_default_offload_fwd_mark(skb);
98
99 return skb;
100}
101
102/*
103 * For Ingress (Host -> KSZ8795), 1 byte is added before FCS.
104 * ---------------------------------------------------------------------------
105 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag(1byte)|FCS(4bytes)
106 * ---------------------------------------------------------------------------
107 * tag : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
108 *
109 * For Egress (KSZ8795 -> Host), 1 byte is added before FCS.
110 * ---------------------------------------------------------------------------
111 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|tag0(1byte)|FCS(4bytes)
112 * ---------------------------------------------------------------------------
113 * tag0 : zero-based value represents port
114 * (eg, 0x00=port1, 0x02=port3, 0x06=port7)
115 */
116
117#define KSZ8795_TAIL_TAG_OVERRIDE BIT(6)
118#define KSZ8795_TAIL_TAG_LOOKUP BIT(7)
119
120static struct sk_buff *ksz8795_xmit(struct sk_buff *skb, struct net_device *dev)
121{
122 struct dsa_port *dp = dsa_user_to_port(dev);
123 struct ethhdr *hdr;
124 u8 *tag;
125
126 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
127 return NULL;
128
129 /* Tag encoding */
130 tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);
131 hdr = skb_eth_hdr(skb);
132
133 *tag = 1 << dp->index;
134 if (is_link_local_ether_addr(addr: hdr->h_dest))
135 *tag |= KSZ8795_TAIL_TAG_OVERRIDE;
136
137 return skb;
138}
139
140static struct sk_buff *ksz8795_rcv(struct sk_buff *skb, struct net_device *dev)
141{
142 u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
143
144 return ksz_common_rcv(skb, dev, port: tag[0] & 7, KSZ_EGRESS_TAG_LEN);
145}
146
147static const struct dsa_device_ops ksz8795_netdev_ops = {
148 .name = KSZ8795_NAME,
149 .proto = DSA_TAG_PROTO_KSZ8795,
150 .xmit = ksz8795_xmit,
151 .rcv = ksz8795_rcv,
152 .needed_tailroom = KSZ_INGRESS_TAG_LEN,
153};
154
155DSA_TAG_DRIVER(ksz8795_netdev_ops);
156MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ8795, KSZ8795_NAME);
157
158/*
159 * For Ingress (Host -> KSZ9477), 2/6 bytes are added before FCS.
160 * ---------------------------------------------------------------------------
161 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|tag1(1byte)|
162 * FCS(4bytes)
163 * ---------------------------------------------------------------------------
164 * ts : time stamp (Present only if PTP is enabled in the Hardware)
165 * tag0 : Prioritization (not used now)
166 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x10=port5)
167 *
168 * For Egress (KSZ9477 -> Host), 1/5 bytes is added before FCS.
169 * ---------------------------------------------------------------------------
170 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes)
171 * ---------------------------------------------------------------------------
172 * ts : time stamp (Present only if bit 7 of tag0 is set)
173 * tag0 : zero-based value represents port
174 * (eg, 0x00=port1, 0x02=port3, 0x06=port7)
175 */
176
177#define KSZ9477_INGRESS_TAG_LEN 2
178#define KSZ9477_PTP_TAG_LEN 4
179#define KSZ9477_PTP_TAG_INDICATION 0x80
180
181#define KSZ9477_TAIL_TAG_PRIO GENMASK(8, 7)
182#define KSZ9477_TAIL_TAG_OVERRIDE BIT(9)
183#define KSZ9477_TAIL_TAG_LOOKUP BIT(10)
184
185static void ksz_rcv_timestamp(struct sk_buff *skb, u8 *tag)
186{
187 u8 *tstamp_raw = tag - KSZ_PTP_TAG_LEN;
188 ktime_t tstamp;
189
190 tstamp = ksz_decode_tstamp(tstamp: get_unaligned_be32(p: tstamp_raw));
191 KSZ_SKB_CB(skb)->tstamp = tstamp;
192}
193
194/* Time stamp tag *needs* to be inserted if PTP is enabled in hardware.
195 * Regardless of Whether it is a PTP frame or not.
196 */
197static void ksz_xmit_timestamp(struct dsa_port *dp, struct sk_buff *skb)
198{
199 struct ksz_tagger_private *priv;
200 struct ptp_header *ptp_hdr;
201 unsigned int ptp_type;
202 u32 tstamp_raw = 0;
203 s64 correction;
204
205 priv = ksz_tagger_private(ds: dp->ds);
206
207 if (!test_bit(KSZ_HWTS_EN, &priv->state))
208 return;
209
210 if (!KSZ_SKB_CB(skb)->update_correction)
211 goto output_tag;
212
213 ptp_type = KSZ_SKB_CB(skb)->ptp_type;
214
215 ptp_hdr = ptp_parse_header(skb, type: ptp_type);
216 if (!ptp_hdr)
217 goto output_tag;
218
219 correction = (s64)get_unaligned_be64(p: &ptp_hdr->correction);
220
221 if (correction < 0) {
222 struct timespec64 ts;
223
224 ts = ns_to_timespec64(nsec: -correction >> 16);
225 tstamp_raw = ((ts.tv_sec & 3) << 30) | ts.tv_nsec;
226
227 /* Set correction field to 0 and update UDP checksum */
228 ptp_header_update_correction(skb, type: ptp_type, hdr: ptp_hdr, correction: 0);
229 }
230
231output_tag:
232 put_unaligned_be32(val: tstamp_raw, p: skb_put(skb, KSZ_PTP_TAG_LEN));
233}
234
235/* Defer transmit if waiting for egress time stamp is required. */
236static struct sk_buff *ksz_defer_xmit(struct dsa_port *dp, struct sk_buff *skb)
237{
238 struct ksz_tagger_data *tagger_data = ksz_tagger_data(ds: dp->ds);
239 struct ksz_tagger_private *priv = ksz_tagger_private(ds: dp->ds);
240 void (*xmit_work_fn)(struct kthread_work *work);
241 struct sk_buff *clone = KSZ_SKB_CB(skb)->clone;
242 struct ksz_deferred_xmit_work *xmit_work;
243 struct kthread_worker *xmit_worker;
244
245 if (!clone)
246 return skb; /* no deferred xmit for this packet */
247
248 xmit_work_fn = tagger_data->xmit_work_fn;
249 xmit_worker = priv->xmit_worker;
250
251 if (!xmit_work_fn || !xmit_worker)
252 return NULL;
253
254 xmit_work = kzalloc(size: sizeof(*xmit_work), GFP_ATOMIC);
255 if (!xmit_work)
256 return NULL;
257
258 kthread_init_work(&xmit_work->work, xmit_work_fn);
259 /* Increase refcount so the kfree_skb in dsa_user_xmit
260 * won't really free the packet.
261 */
262 xmit_work->dp = dp;
263 xmit_work->skb = skb_get(skb);
264
265 kthread_queue_work(worker: xmit_worker, work: &xmit_work->work);
266
267 return NULL;
268}
269
270static struct sk_buff *ksz9477_xmit(struct sk_buff *skb,
271 struct net_device *dev)
272{
273 u16 queue_mapping = skb_get_queue_mapping(skb);
274 u8 prio = netdev_txq_to_tc(dev, txq: queue_mapping);
275 struct dsa_port *dp = dsa_user_to_port(dev);
276 struct ethhdr *hdr;
277 __be16 *tag;
278 u16 val;
279
280 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
281 return NULL;
282
283 /* Tag encoding */
284 ksz_xmit_timestamp(dp, skb);
285
286 tag = skb_put(skb, KSZ9477_INGRESS_TAG_LEN);
287 hdr = skb_eth_hdr(skb);
288
289 val = BIT(dp->index);
290
291 val |= FIELD_PREP(KSZ9477_TAIL_TAG_PRIO, prio);
292
293 if (is_link_local_ether_addr(addr: hdr->h_dest))
294 val |= KSZ9477_TAIL_TAG_OVERRIDE;
295
296 if (dev->features & NETIF_F_HW_HSR_DUP) {
297 struct net_device *hsr_dev = dp->hsr_dev;
298 struct dsa_port *other_dp;
299
300 dsa_hsr_foreach_port(other_dp, dp->ds, hsr_dev)
301 val |= BIT(other_dp->index);
302 }
303
304 *tag = cpu_to_be16(val);
305
306 return ksz_defer_xmit(dp, skb);
307}
308
309static struct sk_buff *ksz9477_rcv(struct sk_buff *skb, struct net_device *dev)
310{
311 /* Tag decoding */
312 u8 *tag = skb_tail_pointer(skb) - KSZ_EGRESS_TAG_LEN;
313 unsigned int port = tag[0] & 7;
314 unsigned int len = KSZ_EGRESS_TAG_LEN;
315
316 /* Extra 4-bytes PTP timestamp */
317 if (tag[0] & KSZ9477_PTP_TAG_INDICATION) {
318 ksz_rcv_timestamp(skb, tag);
319 len += KSZ_PTP_TAG_LEN;
320 }
321
322 return ksz_common_rcv(skb, dev, port, len);
323}
324
325static const struct dsa_device_ops ksz9477_netdev_ops = {
326 .name = KSZ9477_NAME,
327 .proto = DSA_TAG_PROTO_KSZ9477,
328 .xmit = ksz9477_xmit,
329 .rcv = ksz9477_rcv,
330 .connect = ksz_connect,
331 .disconnect = ksz_disconnect,
332 .needed_tailroom = KSZ9477_INGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
333};
334
335DSA_TAG_DRIVER(ksz9477_netdev_ops);
336MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9477, KSZ9477_NAME);
337
338#define KSZ9893_TAIL_TAG_PRIO GENMASK(4, 3)
339#define KSZ9893_TAIL_TAG_OVERRIDE BIT(5)
340#define KSZ9893_TAIL_TAG_LOOKUP BIT(6)
341
342static struct sk_buff *ksz9893_xmit(struct sk_buff *skb,
343 struct net_device *dev)
344{
345 u16 queue_mapping = skb_get_queue_mapping(skb);
346 u8 prio = netdev_txq_to_tc(dev, txq: queue_mapping);
347 struct dsa_port *dp = dsa_user_to_port(dev);
348 struct ethhdr *hdr;
349 u8 *tag;
350
351 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
352 return NULL;
353
354 /* Tag encoding */
355 ksz_xmit_timestamp(dp, skb);
356
357 tag = skb_put(skb, KSZ_INGRESS_TAG_LEN);
358 hdr = skb_eth_hdr(skb);
359
360 *tag = BIT(dp->index);
361
362 *tag |= FIELD_PREP(KSZ9893_TAIL_TAG_PRIO, prio);
363
364 if (is_link_local_ether_addr(addr: hdr->h_dest))
365 *tag |= KSZ9893_TAIL_TAG_OVERRIDE;
366
367 return ksz_defer_xmit(dp, skb);
368}
369
370static const struct dsa_device_ops ksz9893_netdev_ops = {
371 .name = KSZ9893_NAME,
372 .proto = DSA_TAG_PROTO_KSZ9893,
373 .xmit = ksz9893_xmit,
374 .rcv = ksz9477_rcv,
375 .connect = ksz_connect,
376 .disconnect = ksz_disconnect,
377 .needed_tailroom = KSZ_INGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
378};
379
380DSA_TAG_DRIVER(ksz9893_netdev_ops);
381MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_KSZ9893, KSZ9893_NAME);
382
383/* For xmit, 2/6 bytes are added before FCS.
384 * ---------------------------------------------------------------------------
385 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|tag1(1byte)|
386 * FCS(4bytes)
387 * ---------------------------------------------------------------------------
388 * ts : time stamp (Present only if PTP is enabled in the Hardware)
389 * tag0 : represents tag override, lookup and valid
390 * tag1 : each bit represents port (eg, 0x01=port1, 0x02=port2, 0x80=port8)
391 *
392 * For rcv, 1/5 bytes is added before FCS.
393 * ---------------------------------------------------------------------------
394 * DA(6bytes)|SA(6bytes)|....|Data(nbytes)|ts(4bytes)|tag0(1byte)|FCS(4bytes)
395 * ---------------------------------------------------------------------------
396 * ts : time stamp (Present only if bit 7 of tag0 is set)
397 * tag0 : zero-based value represents port
398 * (eg, 0x00=port1, 0x02=port3, 0x07=port8)
399 */
400#define LAN937X_EGRESS_TAG_LEN 2
401
402#define LAN937X_TAIL_TAG_BLOCKING_OVERRIDE BIT(11)
403#define LAN937X_TAIL_TAG_LOOKUP BIT(12)
404#define LAN937X_TAIL_TAG_VALID BIT(13)
405#define LAN937X_TAIL_TAG_PRIO GENMASK(10, 8)
406#define LAN937X_TAIL_TAG_PORT_MASK 7
407
408static struct sk_buff *lan937x_xmit(struct sk_buff *skb,
409 struct net_device *dev)
410{
411 u16 queue_mapping = skb_get_queue_mapping(skb);
412 u8 prio = netdev_txq_to_tc(dev, txq: queue_mapping);
413 struct dsa_port *dp = dsa_user_to_port(dev);
414 const struct ethhdr *hdr = eth_hdr(skb);
415 __be16 *tag;
416 u16 val;
417
418 if (skb->ip_summed == CHECKSUM_PARTIAL && skb_checksum_help(skb))
419 return NULL;
420
421 ksz_xmit_timestamp(dp, skb);
422
423 tag = skb_put(skb, LAN937X_EGRESS_TAG_LEN);
424
425 val = BIT(dp->index);
426
427 val |= FIELD_PREP(LAN937X_TAIL_TAG_PRIO, prio);
428
429 if (is_link_local_ether_addr(addr: hdr->h_dest))
430 val |= LAN937X_TAIL_TAG_BLOCKING_OVERRIDE;
431
432 /* Tail tag valid bit - This bit should always be set by the CPU */
433 val |= LAN937X_TAIL_TAG_VALID;
434
435 put_unaligned_be16(val, p: tag);
436
437 return ksz_defer_xmit(dp, skb);
438}
439
440static const struct dsa_device_ops lan937x_netdev_ops = {
441 .name = LAN937X_NAME,
442 .proto = DSA_TAG_PROTO_LAN937X,
443 .xmit = lan937x_xmit,
444 .rcv = ksz9477_rcv,
445 .connect = ksz_connect,
446 .disconnect = ksz_disconnect,
447 .needed_tailroom = LAN937X_EGRESS_TAG_LEN + KSZ_PTP_TAG_LEN,
448};
449
450DSA_TAG_DRIVER(lan937x_netdev_ops);
451MODULE_ALIAS_DSA_TAG_DRIVER(DSA_TAG_PROTO_LAN937X, LAN937X_NAME);
452
453static struct dsa_tag_driver *dsa_tag_driver_array[] = {
454 &DSA_TAG_DRIVER_NAME(ksz8795_netdev_ops),
455 &DSA_TAG_DRIVER_NAME(ksz9477_netdev_ops),
456 &DSA_TAG_DRIVER_NAME(ksz9893_netdev_ops),
457 &DSA_TAG_DRIVER_NAME(lan937x_netdev_ops),
458};
459
460module_dsa_tag_drivers(dsa_tag_driver_array);
461
462MODULE_LICENSE("GPL");
463

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