xref: /openbmc/linux/drivers/ptp/ptp_ines.c (revision 2cf1c348)
1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (C) 2018 MOSER-BAER AG
4 //
5 
6 #define pr_fmt(fmt) "InES_PTP: " fmt
7 
8 #include <linux/ethtool.h>
9 #include <linux/export.h>
10 #include <linux/if_vlan.h>
11 #include <linux/mii_timestamper.h>
12 #include <linux/module.h>
13 #include <linux/net_tstamp.h>
14 #include <linux/of.h>
15 #include <linux/of_address.h>
16 #include <linux/of_irq.h>
17 #include <linux/phy.h>
18 #include <linux/platform_device.h>
19 #include <linux/ptp_classify.h>
20 #include <linux/ptp_clock_kernel.h>
21 #include <linux/stddef.h>
22 
23 MODULE_DESCRIPTION("Driver for the ZHAW InES PTP time stamping IP core");
24 MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
25 MODULE_VERSION("1.0");
26 MODULE_LICENSE("GPL");
27 
28 /* GLOBAL register */
29 #define MCAST_MAC_SELECT_SHIFT	2
30 #define MCAST_MAC_SELECT_MASK	0x3
31 #define IO_RESET		BIT(1)
32 #define PTP_RESET		BIT(0)
33 
34 /* VERSION register */
35 #define IF_MAJOR_VER_SHIFT	12
36 #define IF_MAJOR_VER_MASK	0xf
37 #define IF_MINOR_VER_SHIFT	8
38 #define IF_MINOR_VER_MASK	0xf
39 #define FPGA_MAJOR_VER_SHIFT	4
40 #define FPGA_MAJOR_VER_MASK	0xf
41 #define FPGA_MINOR_VER_SHIFT	0
42 #define FPGA_MINOR_VER_MASK	0xf
43 
44 /* INT_STAT register */
45 #define RX_INTR_STATUS_3	BIT(5)
46 #define RX_INTR_STATUS_2	BIT(4)
47 #define RX_INTR_STATUS_1	BIT(3)
48 #define TX_INTR_STATUS_3	BIT(2)
49 #define TX_INTR_STATUS_2	BIT(1)
50 #define TX_INTR_STATUS_1	BIT(0)
51 
52 /* INT_MSK register */
53 #define RX_INTR_MASK_3		BIT(5)
54 #define RX_INTR_MASK_2		BIT(4)
55 #define RX_INTR_MASK_1		BIT(3)
56 #define TX_INTR_MASK_3		BIT(2)
57 #define TX_INTR_MASK_2		BIT(1)
58 #define TX_INTR_MASK_1		BIT(0)
59 
60 /* BUF_STAT register */
61 #define RX_FIFO_NE_3		BIT(5)
62 #define RX_FIFO_NE_2		BIT(4)
63 #define RX_FIFO_NE_1		BIT(3)
64 #define TX_FIFO_NE_3		BIT(2)
65 #define TX_FIFO_NE_2		BIT(1)
66 #define TX_FIFO_NE_1		BIT(0)
67 
68 /* PORT_CONF register */
69 #define CM_ONE_STEP		BIT(6)
70 #define PHY_SPEED_SHIFT		4
71 #define PHY_SPEED_MASK		0x3
72 #define P2P_DELAY_WR_POS_SHIFT	2
73 #define P2P_DELAY_WR_POS_MASK	0x3
74 #define PTP_MODE_SHIFT		0
75 #define PTP_MODE_MASK		0x3
76 
77 /* TS_STAT_TX register */
78 #define TS_ENABLE		BIT(15)
79 #define DATA_READ_POS_SHIFT	8
80 #define DATA_READ_POS_MASK	0x1f
81 #define DISCARDED_EVENTS_SHIFT	4
82 #define DISCARDED_EVENTS_MASK	0xf
83 
84 #define INES_N_PORTS		3
85 #define INES_REGISTER_SIZE	0x80
86 #define INES_PORT_OFFSET	0x20
87 #define INES_PORT_SIZE		0x20
88 #define INES_FIFO_DEPTH		90
89 #define INES_MAX_EVENTS		100
90 
91 #define BC_PTP_V1		0
92 #define BC_PTP_V2		1
93 #define TC_E2E_PTP_V2		2
94 #define TC_P2P_PTP_V2		3
95 
96 #define PHY_SPEED_10		0
97 #define PHY_SPEED_100		1
98 #define PHY_SPEED_1000		2
99 
100 #define PORT_CONF \
101 	((PHY_SPEED_1000 << PHY_SPEED_SHIFT) | (BC_PTP_V2 << PTP_MODE_SHIFT))
102 
103 #define ines_read32(s, r)	__raw_readl((void __iomem *)&s->regs->r)
104 #define ines_write32(s, v, r)	__raw_writel(v, (void __iomem *)&s->regs->r)
105 
106 #define MESSAGE_TYPE_SYNC		1
107 #define MESSAGE_TYPE_P_DELAY_REQ	2
108 #define MESSAGE_TYPE_P_DELAY_RESP	3
109 #define MESSAGE_TYPE_DELAY_REQ		4
110 
111 static LIST_HEAD(ines_clocks);
112 static DEFINE_MUTEX(ines_clocks_lock);
113 
114 struct ines_global_regs {
115 	u32 id;
116 	u32 test;
117 	u32 global;
118 	u32 version;
119 	u32 test2;
120 	u32 int_stat;
121 	u32 int_msk;
122 	u32 buf_stat;
123 };
124 
125 struct ines_port_registers {
126 	u32 port_conf;
127 	u32 p_delay;
128 	u32 ts_stat_tx;
129 	u32 ts_stat_rx;
130 	u32 ts_tx;
131 	u32 ts_rx;
132 };
133 
134 struct ines_timestamp {
135 	struct list_head list;
136 	unsigned long	tmo;
137 	u16		tag;
138 	u64		sec;
139 	u64		nsec;
140 	u64		clkid;
141 	u16		portnum;
142 	u16		seqid;
143 };
144 
145 struct ines_port {
146 	struct ines_port_registers	*regs;
147 	struct mii_timestamper		mii_ts;
148 	struct ines_clock		*clock;
149 	bool				rxts_enabled;
150 	bool				txts_enabled;
151 	unsigned int			index;
152 	struct delayed_work		ts_work;
153 	/* lock protects event list and tx_skb */
154 	spinlock_t			lock;
155 	struct sk_buff			*tx_skb;
156 	struct list_head		events;
157 	struct list_head		pool;
158 	struct ines_timestamp		pool_data[INES_MAX_EVENTS];
159 };
160 
161 struct ines_clock {
162 	struct ines_port		port[INES_N_PORTS];
163 	struct ines_global_regs __iomem	*regs;
164 	void __iomem			*base;
165 	struct device_node		*node;
166 	struct device			*dev;
167 	struct list_head		list;
168 };
169 
170 static bool ines_match(struct sk_buff *skb, unsigned int ptp_class,
171 		       struct ines_timestamp *ts, struct device *dev);
172 static int ines_rxfifo_read(struct ines_port *port);
173 static u64 ines_rxts64(struct ines_port *port, unsigned int words);
174 static bool ines_timestamp_expired(struct ines_timestamp *ts);
175 static u64 ines_txts64(struct ines_port *port, unsigned int words);
176 static void ines_txtstamp_work(struct work_struct *work);
177 static bool is_sync_pdelay_resp(struct sk_buff *skb, int type);
178 static u8 tag_to_msgtype(u8 tag);
179 
180 static void ines_clock_cleanup(struct ines_clock *clock)
181 {
182 	struct ines_port *port;
183 	int i;
184 
185 	for (i = 0; i < INES_N_PORTS; i++) {
186 		port = &clock->port[i];
187 		cancel_delayed_work_sync(&port->ts_work);
188 	}
189 }
190 
191 static int ines_clock_init(struct ines_clock *clock, struct device *device,
192 			   void __iomem *addr)
193 {
194 	struct device_node *node = device->of_node;
195 	unsigned long port_addr;
196 	struct ines_port *port;
197 	int i, j;
198 
199 	INIT_LIST_HEAD(&clock->list);
200 	clock->node = node;
201 	clock->dev  = device;
202 	clock->base = addr;
203 	clock->regs = clock->base;
204 
205 	for (i = 0; i < INES_N_PORTS; i++) {
206 		port = &clock->port[i];
207 		port_addr = (unsigned long) clock->base +
208 			INES_PORT_OFFSET + i * INES_PORT_SIZE;
209 		port->regs = (struct ines_port_registers *) port_addr;
210 		port->clock = clock;
211 		port->index = i;
212 		INIT_DELAYED_WORK(&port->ts_work, ines_txtstamp_work);
213 		spin_lock_init(&port->lock);
214 		INIT_LIST_HEAD(&port->events);
215 		INIT_LIST_HEAD(&port->pool);
216 		for (j = 0; j < INES_MAX_EVENTS; j++)
217 			list_add(&port->pool_data[j].list, &port->pool);
218 	}
219 
220 	ines_write32(clock, 0xBEEF, test);
221 	ines_write32(clock, 0xBEEF, test2);
222 
223 	dev_dbg(device, "ID      0x%x\n", ines_read32(clock, id));
224 	dev_dbg(device, "TEST    0x%x\n", ines_read32(clock, test));
225 	dev_dbg(device, "VERSION 0x%x\n", ines_read32(clock, version));
226 	dev_dbg(device, "TEST2   0x%x\n", ines_read32(clock, test2));
227 
228 	for (i = 0; i < INES_N_PORTS; i++) {
229 		port = &clock->port[i];
230 		ines_write32(port, PORT_CONF, port_conf);
231 	}
232 
233 	return 0;
234 }
235 
236 static struct ines_port *ines_find_port(struct device_node *node, u32 index)
237 {
238 	struct ines_port *port = NULL;
239 	struct ines_clock *clock;
240 	struct list_head *this;
241 
242 	mutex_lock(&ines_clocks_lock);
243 	list_for_each(this, &ines_clocks) {
244 		clock = list_entry(this, struct ines_clock, list);
245 		if (clock->node == node) {
246 			port = &clock->port[index];
247 			break;
248 		}
249 	}
250 	mutex_unlock(&ines_clocks_lock);
251 	return port;
252 }
253 
254 static u64 ines_find_rxts(struct ines_port *port, struct sk_buff *skb, int type)
255 {
256 	struct list_head *this, *next;
257 	struct ines_timestamp *ts;
258 	unsigned long flags;
259 	u64 ns = 0;
260 
261 	if (type == PTP_CLASS_NONE)
262 		return 0;
263 
264 	spin_lock_irqsave(&port->lock, flags);
265 	ines_rxfifo_read(port);
266 	list_for_each_safe(this, next, &port->events) {
267 		ts = list_entry(this, struct ines_timestamp, list);
268 		if (ines_timestamp_expired(ts)) {
269 			list_del_init(&ts->list);
270 			list_add(&ts->list, &port->pool);
271 			continue;
272 		}
273 		if (ines_match(skb, type, ts, port->clock->dev)) {
274 			ns = ts->sec * 1000000000ULL + ts->nsec;
275 			list_del_init(&ts->list);
276 			list_add(&ts->list, &port->pool);
277 			break;
278 		}
279 	}
280 	spin_unlock_irqrestore(&port->lock, flags);
281 
282 	return ns;
283 }
284 
285 static u64 ines_find_txts(struct ines_port *port, struct sk_buff *skb)
286 {
287 	unsigned int class = ptp_classify_raw(skb), i;
288 	u32 data_rd_pos, buf_stat, mask, ts_stat_tx;
289 	struct ines_timestamp ts;
290 	unsigned long flags;
291 	u64 ns = 0;
292 
293 	mask = TX_FIFO_NE_1 << port->index;
294 
295 	spin_lock_irqsave(&port->lock, flags);
296 
297 	for (i = 0; i < INES_FIFO_DEPTH; i++) {
298 
299 		buf_stat = ines_read32(port->clock, buf_stat);
300 		if (!(buf_stat & mask)) {
301 			dev_dbg(port->clock->dev,
302 				  "Tx timestamp FIFO unexpectedly empty\n");
303 			break;
304 		}
305 		ts_stat_tx = ines_read32(port, ts_stat_tx);
306 		data_rd_pos = (ts_stat_tx >> DATA_READ_POS_SHIFT) &
307 			DATA_READ_POS_MASK;
308 		if (data_rd_pos) {
309 			dev_err(port->clock->dev,
310 				"unexpected Tx read pos %u\n", data_rd_pos);
311 			break;
312 		}
313 
314 		ts.tag     = ines_read32(port, ts_tx);
315 		ts.sec     = ines_txts64(port, 3);
316 		ts.nsec    = ines_txts64(port, 2);
317 		ts.clkid   = ines_txts64(port, 4);
318 		ts.portnum = ines_read32(port, ts_tx);
319 		ts.seqid   = ines_read32(port, ts_tx);
320 
321 		if (ines_match(skb, class, &ts, port->clock->dev)) {
322 			ns = ts.sec * 1000000000ULL + ts.nsec;
323 			break;
324 		}
325 	}
326 
327 	spin_unlock_irqrestore(&port->lock, flags);
328 	return ns;
329 }
330 
331 static int ines_hwtstamp(struct mii_timestamper *mii_ts, struct ifreq *ifr)
332 {
333 	struct ines_port *port = container_of(mii_ts, struct ines_port, mii_ts);
334 	u32 cm_one_step = 0, port_conf, ts_stat_rx, ts_stat_tx;
335 	struct hwtstamp_config cfg;
336 	unsigned long flags;
337 
338 	if (copy_from_user(&cfg, ifr->ifr_data, sizeof(cfg)))
339 		return -EFAULT;
340 
341 	switch (cfg.tx_type) {
342 	case HWTSTAMP_TX_OFF:
343 		ts_stat_tx = 0;
344 		break;
345 	case HWTSTAMP_TX_ON:
346 		ts_stat_tx = TS_ENABLE;
347 		break;
348 	case HWTSTAMP_TX_ONESTEP_P2P:
349 		ts_stat_tx = TS_ENABLE;
350 		cm_one_step = CM_ONE_STEP;
351 		break;
352 	default:
353 		return -ERANGE;
354 	}
355 
356 	switch (cfg.rx_filter) {
357 	case HWTSTAMP_FILTER_NONE:
358 		ts_stat_rx = 0;
359 		break;
360 	case HWTSTAMP_FILTER_ALL:
361 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
362 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
363 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
364 		return -ERANGE;
365 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
366 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
367 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
368 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
369 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
370 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
371 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
372 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
373 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
374 		ts_stat_rx = TS_ENABLE;
375 		cfg.rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
376 		break;
377 	default:
378 		return -ERANGE;
379 	}
380 
381 	spin_lock_irqsave(&port->lock, flags);
382 
383 	port_conf = ines_read32(port, port_conf);
384 	port_conf &= ~CM_ONE_STEP;
385 	port_conf |= cm_one_step;
386 
387 	ines_write32(port, port_conf, port_conf);
388 	ines_write32(port, ts_stat_rx, ts_stat_rx);
389 	ines_write32(port, ts_stat_tx, ts_stat_tx);
390 
391 	port->rxts_enabled = ts_stat_rx == TS_ENABLE;
392 	port->txts_enabled = ts_stat_tx == TS_ENABLE;
393 
394 	spin_unlock_irqrestore(&port->lock, flags);
395 
396 	return copy_to_user(ifr->ifr_data, &cfg, sizeof(cfg)) ? -EFAULT : 0;
397 }
398 
399 static void ines_link_state(struct mii_timestamper *mii_ts,
400 			    struct phy_device *phydev)
401 {
402 	struct ines_port *port = container_of(mii_ts, struct ines_port, mii_ts);
403 	u32 port_conf, speed_conf;
404 	unsigned long flags;
405 
406 	switch (phydev->speed) {
407 	case SPEED_10:
408 		speed_conf = PHY_SPEED_10 << PHY_SPEED_SHIFT;
409 		break;
410 	case SPEED_100:
411 		speed_conf = PHY_SPEED_100 << PHY_SPEED_SHIFT;
412 		break;
413 	case SPEED_1000:
414 		speed_conf = PHY_SPEED_1000 << PHY_SPEED_SHIFT;
415 		break;
416 	default:
417 		dev_err(port->clock->dev, "bad speed: %d\n", phydev->speed);
418 		return;
419 	}
420 	spin_lock_irqsave(&port->lock, flags);
421 
422 	port_conf = ines_read32(port, port_conf);
423 	port_conf &= ~(0x3 << PHY_SPEED_SHIFT);
424 	port_conf |= speed_conf;
425 
426 	ines_write32(port, port_conf, port_conf);
427 
428 	spin_unlock_irqrestore(&port->lock, flags);
429 }
430 
431 static bool ines_match(struct sk_buff *skb, unsigned int ptp_class,
432 		       struct ines_timestamp *ts, struct device *dev)
433 {
434 	struct ptp_header *hdr;
435 	u16 portn, seqid;
436 	u8 msgtype;
437 	u64 clkid;
438 
439 	if (unlikely(ptp_class & PTP_CLASS_V1))
440 		return false;
441 
442 	hdr = ptp_parse_header(skb, ptp_class);
443 	if (!hdr)
444 		return false;
445 
446 	msgtype = ptp_get_msgtype(hdr, ptp_class);
447 	clkid = be64_to_cpup((__be64 *)&hdr->source_port_identity.clock_identity.id[0]);
448 	portn = be16_to_cpu(hdr->source_port_identity.port_number);
449 	seqid = be16_to_cpu(hdr->sequence_id);
450 
451 	if (tag_to_msgtype(ts->tag & 0x7) != msgtype) {
452 		dev_dbg(dev, "msgtype mismatch ts %hhu != skb %hhu\n",
453 			tag_to_msgtype(ts->tag & 0x7), msgtype);
454 		return false;
455 	}
456 	if (ts->clkid != clkid) {
457 		dev_dbg(dev, "clkid mismatch ts %llx != skb %llx\n",
458 			ts->clkid, clkid);
459 		return false;
460 	}
461 	if (ts->portnum != portn) {
462 		dev_dbg(dev, "portn mismatch ts %hu != skb %hu\n",
463 			ts->portnum, portn);
464 		return false;
465 	}
466 	if (ts->seqid != seqid) {
467 		dev_dbg(dev, "seqid mismatch ts %hu != skb %hu\n",
468 			ts->seqid, seqid);
469 		return false;
470 	}
471 
472 	return true;
473 }
474 
475 static bool ines_rxtstamp(struct mii_timestamper *mii_ts,
476 			  struct sk_buff *skb, int type)
477 {
478 	struct ines_port *port = container_of(mii_ts, struct ines_port, mii_ts);
479 	struct skb_shared_hwtstamps *ssh;
480 	u64 ns;
481 
482 	if (!port->rxts_enabled)
483 		return false;
484 
485 	ns = ines_find_rxts(port, skb, type);
486 	if (!ns)
487 		return false;
488 
489 	ssh = skb_hwtstamps(skb);
490 	ssh->hwtstamp = ns_to_ktime(ns);
491 	netif_rx(skb);
492 
493 	return true;
494 }
495 
496 static int ines_rxfifo_read(struct ines_port *port)
497 {
498 	u32 data_rd_pos, buf_stat, mask, ts_stat_rx;
499 	struct ines_timestamp *ts;
500 	unsigned int i;
501 
502 	mask = RX_FIFO_NE_1 << port->index;
503 
504 	for (i = 0; i < INES_FIFO_DEPTH; i++) {
505 		if (list_empty(&port->pool)) {
506 			dev_err(port->clock->dev, "event pool is empty\n");
507 			return -1;
508 		}
509 		buf_stat = ines_read32(port->clock, buf_stat);
510 		if (!(buf_stat & mask))
511 			break;
512 
513 		ts_stat_rx = ines_read32(port, ts_stat_rx);
514 		data_rd_pos = (ts_stat_rx >> DATA_READ_POS_SHIFT) &
515 			DATA_READ_POS_MASK;
516 		if (data_rd_pos) {
517 			dev_err(port->clock->dev, "unexpected Rx read pos %u\n",
518 				data_rd_pos);
519 			break;
520 		}
521 
522 		ts = list_first_entry(&port->pool, struct ines_timestamp, list);
523 		ts->tmo     = jiffies + HZ;
524 		ts->tag     = ines_read32(port, ts_rx);
525 		ts->sec     = ines_rxts64(port, 3);
526 		ts->nsec    = ines_rxts64(port, 2);
527 		ts->clkid   = ines_rxts64(port, 4);
528 		ts->portnum = ines_read32(port, ts_rx);
529 		ts->seqid   = ines_read32(port, ts_rx);
530 
531 		list_del_init(&ts->list);
532 		list_add_tail(&ts->list, &port->events);
533 	}
534 
535 	return 0;
536 }
537 
538 static u64 ines_rxts64(struct ines_port *port, unsigned int words)
539 {
540 	unsigned int i;
541 	u64 result;
542 	u16 word;
543 
544 	word = ines_read32(port, ts_rx);
545 	result = word;
546 	words--;
547 	for (i = 0; i < words; i++) {
548 		word = ines_read32(port, ts_rx);
549 		result <<= 16;
550 		result |= word;
551 	}
552 	return result;
553 }
554 
555 static bool ines_timestamp_expired(struct ines_timestamp *ts)
556 {
557 	return time_after(jiffies, ts->tmo);
558 }
559 
560 static int ines_ts_info(struct mii_timestamper *mii_ts,
561 			struct ethtool_ts_info *info)
562 {
563 	info->so_timestamping =
564 		SOF_TIMESTAMPING_TX_HARDWARE |
565 		SOF_TIMESTAMPING_TX_SOFTWARE |
566 		SOF_TIMESTAMPING_RX_HARDWARE |
567 		SOF_TIMESTAMPING_RX_SOFTWARE |
568 		SOF_TIMESTAMPING_SOFTWARE |
569 		SOF_TIMESTAMPING_RAW_HARDWARE;
570 
571 	info->phc_index = -1;
572 
573 	info->tx_types =
574 		(1 << HWTSTAMP_TX_OFF) |
575 		(1 << HWTSTAMP_TX_ON) |
576 		(1 << HWTSTAMP_TX_ONESTEP_P2P);
577 
578 	info->rx_filters =
579 		(1 << HWTSTAMP_FILTER_NONE) |
580 		(1 << HWTSTAMP_FILTER_PTP_V2_EVENT);
581 
582 	return 0;
583 }
584 
585 static u64 ines_txts64(struct ines_port *port, unsigned int words)
586 {
587 	unsigned int i;
588 	u64 result;
589 	u16 word;
590 
591 	word = ines_read32(port, ts_tx);
592 	result = word;
593 	words--;
594 	for (i = 0; i < words; i++) {
595 		word = ines_read32(port, ts_tx);
596 		result <<= 16;
597 		result |= word;
598 	}
599 	return result;
600 }
601 
602 static bool ines_txts_onestep(struct ines_port *port, struct sk_buff *skb, int type)
603 {
604 	unsigned long flags;
605 	u32 port_conf;
606 
607 	spin_lock_irqsave(&port->lock, flags);
608 	port_conf = ines_read32(port, port_conf);
609 	spin_unlock_irqrestore(&port->lock, flags);
610 
611 	if (port_conf & CM_ONE_STEP)
612 		return is_sync_pdelay_resp(skb, type);
613 
614 	return false;
615 }
616 
617 static void ines_txtstamp(struct mii_timestamper *mii_ts,
618 			  struct sk_buff *skb, int type)
619 {
620 	struct ines_port *port = container_of(mii_ts, struct ines_port, mii_ts);
621 	struct sk_buff *old_skb = NULL;
622 	unsigned long flags;
623 
624 	if (!port->txts_enabled || ines_txts_onestep(port, skb, type)) {
625 		kfree_skb(skb);
626 		return;
627 	}
628 
629 	spin_lock_irqsave(&port->lock, flags);
630 
631 	if (port->tx_skb)
632 		old_skb = port->tx_skb;
633 
634 	port->tx_skb = skb;
635 
636 	spin_unlock_irqrestore(&port->lock, flags);
637 
638 	kfree_skb(old_skb);
639 
640 	schedule_delayed_work(&port->ts_work, 1);
641 }
642 
643 static void ines_txtstamp_work(struct work_struct *work)
644 {
645 	struct ines_port *port =
646 		container_of(work, struct ines_port, ts_work.work);
647 	struct skb_shared_hwtstamps ssh;
648 	struct sk_buff *skb;
649 	unsigned long flags;
650 	u64 ns;
651 
652 	spin_lock_irqsave(&port->lock, flags);
653 	skb = port->tx_skb;
654 	port->tx_skb = NULL;
655 	spin_unlock_irqrestore(&port->lock, flags);
656 
657 	ns = ines_find_txts(port, skb);
658 	if (!ns) {
659 		kfree_skb(skb);
660 		return;
661 	}
662 	ssh.hwtstamp = ns_to_ktime(ns);
663 	skb_complete_tx_timestamp(skb, &ssh);
664 }
665 
666 static bool is_sync_pdelay_resp(struct sk_buff *skb, int type)
667 {
668 	struct ptp_header *hdr;
669 	u8 msgtype;
670 
671 	hdr = ptp_parse_header(skb, type);
672 	if (!hdr)
673 		return false;
674 
675 	msgtype = ptp_get_msgtype(hdr, type);
676 
677 	switch (msgtype) {
678 	case PTP_MSGTYPE_SYNC:
679 	case PTP_MSGTYPE_PDELAY_RESP:
680 		return true;
681 	default:
682 		return false;
683 	}
684 }
685 
686 static u8 tag_to_msgtype(u8 tag)
687 {
688 	switch (tag) {
689 	case MESSAGE_TYPE_SYNC:
690 		return PTP_MSGTYPE_SYNC;
691 	case MESSAGE_TYPE_P_DELAY_REQ:
692 		return PTP_MSGTYPE_PDELAY_REQ;
693 	case MESSAGE_TYPE_P_DELAY_RESP:
694 		return PTP_MSGTYPE_PDELAY_RESP;
695 	case MESSAGE_TYPE_DELAY_REQ:
696 		return PTP_MSGTYPE_DELAY_REQ;
697 	}
698 	return 0xf;
699 }
700 
701 static struct mii_timestamper *ines_ptp_probe_channel(struct device *device,
702 						      unsigned int index)
703 {
704 	struct device_node *node = device->of_node;
705 	struct ines_port *port;
706 
707 	if (index > INES_N_PORTS - 1) {
708 		dev_err(device, "bad port index %u\n", index);
709 		return ERR_PTR(-EINVAL);
710 	}
711 	port = ines_find_port(node, index);
712 	if (!port) {
713 		dev_err(device, "missing port index %u\n", index);
714 		return ERR_PTR(-ENODEV);
715 	}
716 	port->mii_ts.rxtstamp = ines_rxtstamp;
717 	port->mii_ts.txtstamp = ines_txtstamp;
718 	port->mii_ts.hwtstamp = ines_hwtstamp;
719 	port->mii_ts.link_state = ines_link_state;
720 	port->mii_ts.ts_info = ines_ts_info;
721 
722 	return &port->mii_ts;
723 }
724 
725 static void ines_ptp_release_channel(struct device *device,
726 				     struct mii_timestamper *mii_ts)
727 {
728 }
729 
730 static struct mii_timestamping_ctrl ines_ctrl = {
731 	.probe_channel = ines_ptp_probe_channel,
732 	.release_channel = ines_ptp_release_channel,
733 };
734 
735 static int ines_ptp_ctrl_probe(struct platform_device *pld)
736 {
737 	struct ines_clock *clock;
738 	void __iomem *addr;
739 	int err = 0;
740 
741 	addr = devm_platform_ioremap_resource(pld, 0);
742 	if (IS_ERR(addr)) {
743 		err = PTR_ERR(addr);
744 		goto out;
745 	}
746 	clock = kzalloc(sizeof(*clock), GFP_KERNEL);
747 	if (!clock) {
748 		err = -ENOMEM;
749 		goto out;
750 	}
751 	if (ines_clock_init(clock, &pld->dev, addr)) {
752 		kfree(clock);
753 		err = -ENOMEM;
754 		goto out;
755 	}
756 	err = register_mii_tstamp_controller(&pld->dev, &ines_ctrl);
757 	if (err) {
758 		kfree(clock);
759 		goto out;
760 	}
761 	mutex_lock(&ines_clocks_lock);
762 	list_add_tail(&ines_clocks, &clock->list);
763 	mutex_unlock(&ines_clocks_lock);
764 
765 	dev_set_drvdata(&pld->dev, clock);
766 out:
767 	return err;
768 }
769 
770 static int ines_ptp_ctrl_remove(struct platform_device *pld)
771 {
772 	struct ines_clock *clock = dev_get_drvdata(&pld->dev);
773 
774 	unregister_mii_tstamp_controller(&pld->dev);
775 	mutex_lock(&ines_clocks_lock);
776 	list_del(&clock->list);
777 	mutex_unlock(&ines_clocks_lock);
778 	ines_clock_cleanup(clock);
779 	kfree(clock);
780 	return 0;
781 }
782 
783 static const struct of_device_id ines_ptp_ctrl_of_match[] = {
784 	{ .compatible = "ines,ptp-ctrl" },
785 	{ }
786 };
787 
788 MODULE_DEVICE_TABLE(of, ines_ptp_ctrl_of_match);
789 
790 static struct platform_driver ines_ptp_ctrl_driver = {
791 	.probe  = ines_ptp_ctrl_probe,
792 	.remove = ines_ptp_ctrl_remove,
793 	.driver = {
794 		.name = "ines_ptp_ctrl",
795 		.of_match_table = of_match_ptr(ines_ptp_ctrl_of_match),
796 	},
797 };
798 module_platform_driver(ines_ptp_ctrl_driver);
799