xref: /openbmc/linux/drivers/net/ethernet/sfc/ptp.c (revision 20e2fc42)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /****************************************************************************
3  * Driver for Solarflare network controllers and boards
4  * Copyright 2011-2013 Solarflare Communications Inc.
5  */
6 
7 /* Theory of operation:
8  *
9  * PTP support is assisted by firmware running on the MC, which provides
10  * the hardware timestamping capabilities.  Both transmitted and received
11  * PTP event packets are queued onto internal queues for subsequent processing;
12  * this is because the MC operations are relatively long and would block
13  * block NAPI/interrupt operation.
14  *
15  * Receive event processing:
16  *	The event contains the packet's UUID and sequence number, together
17  *	with the hardware timestamp.  The PTP receive packet queue is searched
18  *	for this UUID/sequence number and, if found, put on a pending queue.
19  *	Packets not matching are delivered without timestamps (MCDI events will
20  *	always arrive after the actual packet).
21  *	It is important for the operation of the PTP protocol that the ordering
22  *	of packets between the event and general port is maintained.
23  *
24  * Work queue processing:
25  *	If work waiting, synchronise host/hardware time
26  *
27  *	Transmit: send packet through MC, which returns the transmission time
28  *	that is converted to an appropriate timestamp.
29  *
30  *	Receive: the packet's reception time is converted to an appropriate
31  *	timestamp.
32  */
33 #include <linux/ip.h>
34 #include <linux/udp.h>
35 #include <linux/time.h>
36 #include <linux/ktime.h>
37 #include <linux/module.h>
38 #include <linux/net_tstamp.h>
39 #include <linux/pps_kernel.h>
40 #include <linux/ptp_clock_kernel.h>
41 #include "net_driver.h"
42 #include "efx.h"
43 #include "mcdi.h"
44 #include "mcdi_pcol.h"
45 #include "io.h"
46 #include "farch_regs.h"
47 #include "nic.h"
48 
49 /* Maximum number of events expected to make up a PTP event */
50 #define	MAX_EVENT_FRAGS			3
51 
52 /* Maximum delay, ms, to begin synchronisation */
53 #define	MAX_SYNCHRONISE_WAIT_MS		2
54 
55 /* How long, at most, to spend synchronising */
56 #define	SYNCHRONISE_PERIOD_NS		250000
57 
58 /* How often to update the shared memory time */
59 #define	SYNCHRONISATION_GRANULARITY_NS	200
60 
61 /* Minimum permitted length of a (corrected) synchronisation time */
62 #define	DEFAULT_MIN_SYNCHRONISATION_NS	120
63 
64 /* Maximum permitted length of a (corrected) synchronisation time */
65 #define	MAX_SYNCHRONISATION_NS		1000
66 
67 /* How many (MC) receive events that can be queued */
68 #define	MAX_RECEIVE_EVENTS		8
69 
70 /* Length of (modified) moving average. */
71 #define	AVERAGE_LENGTH			16
72 
73 /* How long an unmatched event or packet can be held */
74 #define PKT_EVENT_LIFETIME_MS		10
75 
76 /* Offsets into PTP packet for identification.  These offsets are from the
77  * start of the IP header, not the MAC header.  Note that neither PTP V1 nor
78  * PTP V2 permit the use of IPV4 options.
79  */
80 #define PTP_DPORT_OFFSET	22
81 
82 #define PTP_V1_VERSION_LENGTH	2
83 #define PTP_V1_VERSION_OFFSET	28
84 
85 #define PTP_V1_UUID_LENGTH	6
86 #define PTP_V1_UUID_OFFSET	50
87 
88 #define PTP_V1_SEQUENCE_LENGTH	2
89 #define PTP_V1_SEQUENCE_OFFSET	58
90 
91 /* The minimum length of a PTP V1 packet for offsets, etc. to be valid:
92  * includes IP header.
93  */
94 #define	PTP_V1_MIN_LENGTH	64
95 
96 #define PTP_V2_VERSION_LENGTH	1
97 #define PTP_V2_VERSION_OFFSET	29
98 
99 #define PTP_V2_UUID_LENGTH	8
100 #define PTP_V2_UUID_OFFSET	48
101 
102 /* Although PTP V2 UUIDs are comprised a ClockIdentity (8) and PortNumber (2),
103  * the MC only captures the last six bytes of the clock identity. These values
104  * reflect those, not the ones used in the standard.  The standard permits
105  * mapping of V1 UUIDs to V2 UUIDs with these same values.
106  */
107 #define PTP_V2_MC_UUID_LENGTH	6
108 #define PTP_V2_MC_UUID_OFFSET	50
109 
110 #define PTP_V2_SEQUENCE_LENGTH	2
111 #define PTP_V2_SEQUENCE_OFFSET	58
112 
113 /* The minimum length of a PTP V2 packet for offsets, etc. to be valid:
114  * includes IP header.
115  */
116 #define	PTP_V2_MIN_LENGTH	63
117 
118 #define	PTP_MIN_LENGTH		63
119 
120 #define PTP_ADDRESS		0xe0000181	/* 224.0.1.129 */
121 #define PTP_EVENT_PORT		319
122 #define PTP_GENERAL_PORT	320
123 
124 /* Annoyingly the format of the version numbers are different between
125  * versions 1 and 2 so it isn't possible to simply look for 1 or 2.
126  */
127 #define	PTP_VERSION_V1		1
128 
129 #define	PTP_VERSION_V2		2
130 #define	PTP_VERSION_V2_MASK	0x0f
131 
132 enum ptp_packet_state {
133 	PTP_PACKET_STATE_UNMATCHED = 0,
134 	PTP_PACKET_STATE_MATCHED,
135 	PTP_PACKET_STATE_TIMED_OUT,
136 	PTP_PACKET_STATE_MATCH_UNWANTED
137 };
138 
139 /* NIC synchronised with single word of time only comprising
140  * partial seconds and full nanoseconds: 10^9 ~ 2^30 so 2 bits for seconds.
141  */
142 #define	MC_NANOSECOND_BITS	30
143 #define	MC_NANOSECOND_MASK	((1 << MC_NANOSECOND_BITS) - 1)
144 #define	MC_SECOND_MASK		((1 << (32 - MC_NANOSECOND_BITS)) - 1)
145 
146 /* Maximum parts-per-billion adjustment that is acceptable */
147 #define MAX_PPB			1000000
148 
149 /* Precalculate scale word to avoid long long division at runtime */
150 /* This is equivalent to 2^66 / 10^9. */
151 #define PPB_SCALE_WORD  ((1LL << (57)) / 1953125LL)
152 
153 /* How much to shift down after scaling to convert to FP40 */
154 #define PPB_SHIFT_FP40		26
155 /* ... and FP44. */
156 #define PPB_SHIFT_FP44		22
157 
158 #define PTP_SYNC_ATTEMPTS	4
159 
160 /**
161  * struct efx_ptp_match - Matching structure, stored in sk_buff's cb area.
162  * @words: UUID and (partial) sequence number
163  * @expiry: Time after which the packet should be delivered irrespective of
164  *            event arrival.
165  * @state: The state of the packet - whether it is ready for processing or
166  *         whether that is of no interest.
167  */
168 struct efx_ptp_match {
169 	u32 words[DIV_ROUND_UP(PTP_V1_UUID_LENGTH, 4)];
170 	unsigned long expiry;
171 	enum ptp_packet_state state;
172 };
173 
174 /**
175  * struct efx_ptp_event_rx - A PTP receive event (from MC)
176  * @seq0: First part of (PTP) UUID
177  * @seq1: Second part of (PTP) UUID and sequence number
178  * @hwtimestamp: Event timestamp
179  */
180 struct efx_ptp_event_rx {
181 	struct list_head link;
182 	u32 seq0;
183 	u32 seq1;
184 	ktime_t hwtimestamp;
185 	unsigned long expiry;
186 };
187 
188 /**
189  * struct efx_ptp_timeset - Synchronisation between host and MC
190  * @host_start: Host time immediately before hardware timestamp taken
191  * @major: Hardware timestamp, major
192  * @minor: Hardware timestamp, minor
193  * @host_end: Host time immediately after hardware timestamp taken
194  * @wait: Number of NIC clock ticks between hardware timestamp being read and
195  *          host end time being seen
196  * @window: Difference of host_end and host_start
197  * @valid: Whether this timeset is valid
198  */
199 struct efx_ptp_timeset {
200 	u32 host_start;
201 	u32 major;
202 	u32 minor;
203 	u32 host_end;
204 	u32 wait;
205 	u32 window;	/* Derived: end - start, allowing for wrap */
206 };
207 
208 /**
209  * struct efx_ptp_data - Precision Time Protocol (PTP) state
210  * @efx: The NIC context
211  * @channel: The PTP channel (Siena only)
212  * @rx_ts_inline: Flag for whether RX timestamps are inline (else they are
213  *	separate events)
214  * @rxq: Receive SKB queue (awaiting timestamps)
215  * @txq: Transmit SKB queue
216  * @evt_list: List of MC receive events awaiting packets
217  * @evt_free_list: List of free events
218  * @evt_lock: Lock for manipulating evt_list and evt_free_list
219  * @rx_evts: Instantiated events (on evt_list and evt_free_list)
220  * @workwq: Work queue for processing pending PTP operations
221  * @work: Work task
222  * @reset_required: A serious error has occurred and the PTP task needs to be
223  *                  reset (disable, enable).
224  * @rxfilter_event: Receive filter when operating
225  * @rxfilter_general: Receive filter when operating
226  * @config: Current timestamp configuration
227  * @enabled: PTP operation enabled
228  * @mode: Mode in which PTP operating (PTP version)
229  * @ns_to_nic_time: Function to convert from scalar nanoseconds to NIC time
230  * @nic_to_kernel_time: Function to convert from NIC to kernel time
231  * @nic_time.minor_max: Wrap point for NIC minor times
232  * @nic_time.sync_event_diff_min: Minimum acceptable difference between time
233  * in packet prefix and last MCDI time sync event i.e. how much earlier than
234  * the last sync event time a packet timestamp can be.
235  * @nic_time.sync_event_diff_max: Maximum acceptable difference between time
236  * in packet prefix and last MCDI time sync event i.e. how much later than
237  * the last sync event time a packet timestamp can be.
238  * @nic_time.sync_event_minor_shift: Shift required to make minor time from
239  * field in MCDI time sync event.
240  * @min_synchronisation_ns: Minimum acceptable corrected sync window
241  * @capabilities: Capabilities flags from the NIC
242  * @ts_corrections.ptp_tx: Required driver correction of PTP packet transmit
243  *                         timestamps
244  * @ts_corrections.ptp_rx: Required driver correction of PTP packet receive
245  *                         timestamps
246  * @ts_corrections.pps_out: PPS output error (information only)
247  * @ts_corrections.pps_in: Required driver correction of PPS input timestamps
248  * @ts_corrections.general_tx: Required driver correction of general packet
249  *                             transmit timestamps
250  * @ts_corrections.general_rx: Required driver correction of general packet
251  *                             receive timestamps
252  * @evt_frags: Partly assembled PTP events
253  * @evt_frag_idx: Current fragment number
254  * @evt_code: Last event code
255  * @start: Address at which MC indicates ready for synchronisation
256  * @host_time_pps: Host time at last PPS
257  * @adjfreq_ppb_shift: Shift required to convert scaled parts-per-billion
258  * frequency adjustment into a fixed point fractional nanosecond format.
259  * @current_adjfreq: Current ppb adjustment.
260  * @phc_clock: Pointer to registered phc device (if primary function)
261  * @phc_clock_info: Registration structure for phc device
262  * @pps_work: pps work task for handling pps events
263  * @pps_workwq: pps work queue
264  * @nic_ts_enabled: Flag indicating if NIC generated TS events are handled
265  * @txbuf: Buffer for use when transmitting (PTP) packets to MC (avoids
266  *         allocations in main data path).
267  * @good_syncs: Number of successful synchronisations.
268  * @fast_syncs: Number of synchronisations requiring short delay
269  * @bad_syncs: Number of failed synchronisations.
270  * @sync_timeouts: Number of synchronisation timeouts
271  * @no_time_syncs: Number of synchronisations with no good times.
272  * @invalid_sync_windows: Number of sync windows with bad durations.
273  * @undersize_sync_windows: Number of corrected sync windows that are too small
274  * @oversize_sync_windows: Number of corrected sync windows that are too large
275  * @rx_no_timestamp: Number of packets received without a timestamp.
276  * @timeset: Last set of synchronisation statistics.
277  * @xmit_skb: Transmit SKB function.
278  */
279 struct efx_ptp_data {
280 	struct efx_nic *efx;
281 	struct efx_channel *channel;
282 	bool rx_ts_inline;
283 	struct sk_buff_head rxq;
284 	struct sk_buff_head txq;
285 	struct list_head evt_list;
286 	struct list_head evt_free_list;
287 	spinlock_t evt_lock;
288 	struct efx_ptp_event_rx rx_evts[MAX_RECEIVE_EVENTS];
289 	struct workqueue_struct *workwq;
290 	struct work_struct work;
291 	bool reset_required;
292 	u32 rxfilter_event;
293 	u32 rxfilter_general;
294 	bool rxfilter_installed;
295 	struct hwtstamp_config config;
296 	bool enabled;
297 	unsigned int mode;
298 	void (*ns_to_nic_time)(s64 ns, u32 *nic_major, u32 *nic_minor);
299 	ktime_t (*nic_to_kernel_time)(u32 nic_major, u32 nic_minor,
300 				      s32 correction);
301 	struct {
302 		u32 minor_max;
303 		u32 sync_event_diff_min;
304 		u32 sync_event_diff_max;
305 		unsigned int sync_event_minor_shift;
306 	} nic_time;
307 	unsigned int min_synchronisation_ns;
308 	unsigned int capabilities;
309 	struct {
310 		s32 ptp_tx;
311 		s32 ptp_rx;
312 		s32 pps_out;
313 		s32 pps_in;
314 		s32 general_tx;
315 		s32 general_rx;
316 	} ts_corrections;
317 	efx_qword_t evt_frags[MAX_EVENT_FRAGS];
318 	int evt_frag_idx;
319 	int evt_code;
320 	struct efx_buffer start;
321 	struct pps_event_time host_time_pps;
322 	unsigned int adjfreq_ppb_shift;
323 	s64 current_adjfreq;
324 	struct ptp_clock *phc_clock;
325 	struct ptp_clock_info phc_clock_info;
326 	struct work_struct pps_work;
327 	struct workqueue_struct *pps_workwq;
328 	bool nic_ts_enabled;
329 	_MCDI_DECLARE_BUF(txbuf, MC_CMD_PTP_IN_TRANSMIT_LENMAX);
330 
331 	unsigned int good_syncs;
332 	unsigned int fast_syncs;
333 	unsigned int bad_syncs;
334 	unsigned int sync_timeouts;
335 	unsigned int no_time_syncs;
336 	unsigned int invalid_sync_windows;
337 	unsigned int undersize_sync_windows;
338 	unsigned int oversize_sync_windows;
339 	unsigned int rx_no_timestamp;
340 	struct efx_ptp_timeset
341 	timeset[MC_CMD_PTP_OUT_SYNCHRONIZE_TIMESET_MAXNUM];
342 	void (*xmit_skb)(struct efx_nic *efx, struct sk_buff *skb);
343 };
344 
345 static int efx_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta);
346 static int efx_phc_adjtime(struct ptp_clock_info *ptp, s64 delta);
347 static int efx_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts);
348 static int efx_phc_settime(struct ptp_clock_info *ptp,
349 			   const struct timespec64 *e_ts);
350 static int efx_phc_enable(struct ptp_clock_info *ptp,
351 			  struct ptp_clock_request *request, int on);
352 
353 bool efx_ptp_use_mac_tx_timestamps(struct efx_nic *efx)
354 {
355 	struct efx_ef10_nic_data *nic_data = efx->nic_data;
356 
357 	return ((efx_nic_rev(efx) >= EFX_REV_HUNT_A0) &&
358 		(nic_data->datapath_caps2 &
359 		 (1 << MC_CMD_GET_CAPABILITIES_V2_OUT_TX_MAC_TIMESTAMPING_LBN)
360 		));
361 }
362 
363 /* PTP 'extra' channel is still a traffic channel, but we only create TX queues
364  * if PTP uses MAC TX timestamps, not if PTP uses the MC directly to transmit.
365  */
366 static bool efx_ptp_want_txqs(struct efx_channel *channel)
367 {
368 	return efx_ptp_use_mac_tx_timestamps(channel->efx);
369 }
370 
371 #define PTP_SW_STAT(ext_name, field_name)				\
372 	{ #ext_name, 0, offsetof(struct efx_ptp_data, field_name) }
373 #define PTP_MC_STAT(ext_name, mcdi_name)				\
374 	{ #ext_name, 32, MC_CMD_PTP_OUT_STATUS_STATS_ ## mcdi_name ## _OFST }
375 static const struct efx_hw_stat_desc efx_ptp_stat_desc[] = {
376 	PTP_SW_STAT(ptp_good_syncs, good_syncs),
377 	PTP_SW_STAT(ptp_fast_syncs, fast_syncs),
378 	PTP_SW_STAT(ptp_bad_syncs, bad_syncs),
379 	PTP_SW_STAT(ptp_sync_timeouts, sync_timeouts),
380 	PTP_SW_STAT(ptp_no_time_syncs, no_time_syncs),
381 	PTP_SW_STAT(ptp_invalid_sync_windows, invalid_sync_windows),
382 	PTP_SW_STAT(ptp_undersize_sync_windows, undersize_sync_windows),
383 	PTP_SW_STAT(ptp_oversize_sync_windows, oversize_sync_windows),
384 	PTP_SW_STAT(ptp_rx_no_timestamp, rx_no_timestamp),
385 	PTP_MC_STAT(ptp_tx_timestamp_packets, TX),
386 	PTP_MC_STAT(ptp_rx_timestamp_packets, RX),
387 	PTP_MC_STAT(ptp_timestamp_packets, TS),
388 	PTP_MC_STAT(ptp_filter_matches, FM),
389 	PTP_MC_STAT(ptp_non_filter_matches, NFM),
390 };
391 #define PTP_STAT_COUNT ARRAY_SIZE(efx_ptp_stat_desc)
392 static const unsigned long efx_ptp_stat_mask[] = {
393 	[0 ... BITS_TO_LONGS(PTP_STAT_COUNT) - 1] = ~0UL,
394 };
395 
396 size_t efx_ptp_describe_stats(struct efx_nic *efx, u8 *strings)
397 {
398 	if (!efx->ptp_data)
399 		return 0;
400 
401 	return efx_nic_describe_stats(efx_ptp_stat_desc, PTP_STAT_COUNT,
402 				      efx_ptp_stat_mask, strings);
403 }
404 
405 size_t efx_ptp_update_stats(struct efx_nic *efx, u64 *stats)
406 {
407 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_STATUS_LEN);
408 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_STATUS_LEN);
409 	size_t i;
410 	int rc;
411 
412 	if (!efx->ptp_data)
413 		return 0;
414 
415 	/* Copy software statistics */
416 	for (i = 0; i < PTP_STAT_COUNT; i++) {
417 		if (efx_ptp_stat_desc[i].dma_width)
418 			continue;
419 		stats[i] = *(unsigned int *)((char *)efx->ptp_data +
420 					     efx_ptp_stat_desc[i].offset);
421 	}
422 
423 	/* Fetch MC statistics.  We *must* fill in all statistics or
424 	 * risk leaking kernel memory to userland, so if the MCDI
425 	 * request fails we pretend we got zeroes.
426 	 */
427 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_STATUS);
428 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
429 	rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
430 			  outbuf, sizeof(outbuf), NULL);
431 	if (rc)
432 		memset(outbuf, 0, sizeof(outbuf));
433 	efx_nic_update_stats(efx_ptp_stat_desc, PTP_STAT_COUNT,
434 			     efx_ptp_stat_mask,
435 			     stats, _MCDI_PTR(outbuf, 0), false);
436 
437 	return PTP_STAT_COUNT;
438 }
439 
440 /* For Siena platforms NIC time is s and ns */
441 static void efx_ptp_ns_to_s_ns(s64 ns, u32 *nic_major, u32 *nic_minor)
442 {
443 	struct timespec64 ts = ns_to_timespec64(ns);
444 	*nic_major = (u32)ts.tv_sec;
445 	*nic_minor = ts.tv_nsec;
446 }
447 
448 static ktime_t efx_ptp_s_ns_to_ktime_correction(u32 nic_major, u32 nic_minor,
449 						s32 correction)
450 {
451 	ktime_t kt = ktime_set(nic_major, nic_minor);
452 	if (correction >= 0)
453 		kt = ktime_add_ns(kt, (u64)correction);
454 	else
455 		kt = ktime_sub_ns(kt, (u64)-correction);
456 	return kt;
457 }
458 
459 /* To convert from s27 format to ns we multiply then divide by a power of 2.
460  * For the conversion from ns to s27, the operation is also converted to a
461  * multiply and shift.
462  */
463 #define S27_TO_NS_SHIFT	(27)
464 #define NS_TO_S27_MULT	(((1ULL << 63) + NSEC_PER_SEC / 2) / NSEC_PER_SEC)
465 #define NS_TO_S27_SHIFT	(63 - S27_TO_NS_SHIFT)
466 #define S27_MINOR_MAX	(1 << S27_TO_NS_SHIFT)
467 
468 /* For Huntington platforms NIC time is in seconds and fractions of a second
469  * where the minor register only uses 27 bits in units of 2^-27s.
470  */
471 static void efx_ptp_ns_to_s27(s64 ns, u32 *nic_major, u32 *nic_minor)
472 {
473 	struct timespec64 ts = ns_to_timespec64(ns);
474 	u32 maj = (u32)ts.tv_sec;
475 	u32 min = (u32)(((u64)ts.tv_nsec * NS_TO_S27_MULT +
476 			 (1ULL << (NS_TO_S27_SHIFT - 1))) >> NS_TO_S27_SHIFT);
477 
478 	/* The conversion can result in the minor value exceeding the maximum.
479 	 * In this case, round up to the next second.
480 	 */
481 	if (min >= S27_MINOR_MAX) {
482 		min -= S27_MINOR_MAX;
483 		maj++;
484 	}
485 
486 	*nic_major = maj;
487 	*nic_minor = min;
488 }
489 
490 static inline ktime_t efx_ptp_s27_to_ktime(u32 nic_major, u32 nic_minor)
491 {
492 	u32 ns = (u32)(((u64)nic_minor * NSEC_PER_SEC +
493 			(1ULL << (S27_TO_NS_SHIFT - 1))) >> S27_TO_NS_SHIFT);
494 	return ktime_set(nic_major, ns);
495 }
496 
497 static ktime_t efx_ptp_s27_to_ktime_correction(u32 nic_major, u32 nic_minor,
498 					       s32 correction)
499 {
500 	/* Apply the correction and deal with carry */
501 	nic_minor += correction;
502 	if ((s32)nic_minor < 0) {
503 		nic_minor += S27_MINOR_MAX;
504 		nic_major--;
505 	} else if (nic_minor >= S27_MINOR_MAX) {
506 		nic_minor -= S27_MINOR_MAX;
507 		nic_major++;
508 	}
509 
510 	return efx_ptp_s27_to_ktime(nic_major, nic_minor);
511 }
512 
513 /* For Medford2 platforms the time is in seconds and quarter nanoseconds. */
514 static void efx_ptp_ns_to_s_qns(s64 ns, u32 *nic_major, u32 *nic_minor)
515 {
516 	struct timespec64 ts = ns_to_timespec64(ns);
517 
518 	*nic_major = (u32)ts.tv_sec;
519 	*nic_minor = ts.tv_nsec * 4;
520 }
521 
522 static ktime_t efx_ptp_s_qns_to_ktime_correction(u32 nic_major, u32 nic_minor,
523 						 s32 correction)
524 {
525 	ktime_t kt;
526 
527 	nic_minor = DIV_ROUND_CLOSEST(nic_minor, 4);
528 	correction = DIV_ROUND_CLOSEST(correction, 4);
529 
530 	kt = ktime_set(nic_major, nic_minor);
531 
532 	if (correction >= 0)
533 		kt = ktime_add_ns(kt, (u64)correction);
534 	else
535 		kt = ktime_sub_ns(kt, (u64)-correction);
536 	return kt;
537 }
538 
539 struct efx_channel *efx_ptp_channel(struct efx_nic *efx)
540 {
541 	return efx->ptp_data ? efx->ptp_data->channel : NULL;
542 }
543 
544 static u32 last_sync_timestamp_major(struct efx_nic *efx)
545 {
546 	struct efx_channel *channel = efx_ptp_channel(efx);
547 	u32 major = 0;
548 
549 	if (channel)
550 		major = channel->sync_timestamp_major;
551 	return major;
552 }
553 
554 /* The 8000 series and later can provide the time from the MAC, which is only
555  * 48 bits long and provides meta-information in the top 2 bits.
556  */
557 static ktime_t
558 efx_ptp_mac_nic_to_ktime_correction(struct efx_nic *efx,
559 				    struct efx_ptp_data *ptp,
560 				    u32 nic_major, u32 nic_minor,
561 				    s32 correction)
562 {
563 	ktime_t kt = { 0 };
564 
565 	if (!(nic_major & 0x80000000)) {
566 		WARN_ON_ONCE(nic_major >> 16);
567 		/* Use the top bits from the latest sync event. */
568 		nic_major &= 0xffff;
569 		nic_major |= (last_sync_timestamp_major(efx) & 0xffff0000);
570 
571 		kt = ptp->nic_to_kernel_time(nic_major, nic_minor,
572 					     correction);
573 	}
574 	return kt;
575 }
576 
577 ktime_t efx_ptp_nic_to_kernel_time(struct efx_tx_queue *tx_queue)
578 {
579 	struct efx_nic *efx = tx_queue->efx;
580 	struct efx_ptp_data *ptp = efx->ptp_data;
581 	ktime_t kt;
582 
583 	if (efx_ptp_use_mac_tx_timestamps(efx))
584 		kt = efx_ptp_mac_nic_to_ktime_correction(efx, ptp,
585 				tx_queue->completed_timestamp_major,
586 				tx_queue->completed_timestamp_minor,
587 				ptp->ts_corrections.general_tx);
588 	else
589 		kt = ptp->nic_to_kernel_time(
590 				tx_queue->completed_timestamp_major,
591 				tx_queue->completed_timestamp_minor,
592 				ptp->ts_corrections.general_tx);
593 	return kt;
594 }
595 
596 /* Get PTP attributes and set up time conversions */
597 static int efx_ptp_get_attributes(struct efx_nic *efx)
598 {
599 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_GET_ATTRIBUTES_LEN);
600 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_GET_ATTRIBUTES_LEN);
601 	struct efx_ptp_data *ptp = efx->ptp_data;
602 	int rc;
603 	u32 fmt;
604 	size_t out_len;
605 
606 	/* Get the PTP attributes. If the NIC doesn't support the operation we
607 	 * use the default format for compatibility with older NICs i.e.
608 	 * seconds and nanoseconds.
609 	 */
610 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_GET_ATTRIBUTES);
611 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
612 	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
613 				outbuf, sizeof(outbuf), &out_len);
614 	if (rc == 0) {
615 		fmt = MCDI_DWORD(outbuf, PTP_OUT_GET_ATTRIBUTES_TIME_FORMAT);
616 	} else if (rc == -EINVAL) {
617 		fmt = MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_NANOSECONDS;
618 	} else if (rc == -EPERM) {
619 		netif_info(efx, probe, efx->net_dev, "no PTP support\n");
620 		return rc;
621 	} else {
622 		efx_mcdi_display_error(efx, MC_CMD_PTP, sizeof(inbuf),
623 				       outbuf, sizeof(outbuf), rc);
624 		return rc;
625 	}
626 
627 	switch (fmt) {
628 	case MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_27FRACTION:
629 		ptp->ns_to_nic_time = efx_ptp_ns_to_s27;
630 		ptp->nic_to_kernel_time = efx_ptp_s27_to_ktime_correction;
631 		ptp->nic_time.minor_max = 1 << 27;
632 		ptp->nic_time.sync_event_minor_shift = 19;
633 		break;
634 	case MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_NANOSECONDS:
635 		ptp->ns_to_nic_time = efx_ptp_ns_to_s_ns;
636 		ptp->nic_to_kernel_time = efx_ptp_s_ns_to_ktime_correction;
637 		ptp->nic_time.minor_max = 1000000000;
638 		ptp->nic_time.sync_event_minor_shift = 22;
639 		break;
640 	case MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_QTR_NANOSECONDS:
641 		ptp->ns_to_nic_time = efx_ptp_ns_to_s_qns;
642 		ptp->nic_to_kernel_time = efx_ptp_s_qns_to_ktime_correction;
643 		ptp->nic_time.minor_max = 4000000000UL;
644 		ptp->nic_time.sync_event_minor_shift = 24;
645 		break;
646 	default:
647 		return -ERANGE;
648 	}
649 
650 	/* Precalculate acceptable difference between the minor time in the
651 	 * packet prefix and the last MCDI time sync event. We expect the
652 	 * packet prefix timestamp to be after of sync event by up to one
653 	 * sync event interval (0.25s) but we allow it to exceed this by a
654 	 * fuzz factor of (0.1s)
655 	 */
656 	ptp->nic_time.sync_event_diff_min = ptp->nic_time.minor_max
657 		- (ptp->nic_time.minor_max / 10);
658 	ptp->nic_time.sync_event_diff_max = (ptp->nic_time.minor_max / 4)
659 		+ (ptp->nic_time.minor_max / 10);
660 
661 	/* MC_CMD_PTP_OP_GET_ATTRIBUTES has been extended twice from an older
662 	 * operation MC_CMD_PTP_OP_GET_TIME_FORMAT. The function now may return
663 	 * a value to use for the minimum acceptable corrected synchronization
664 	 * window and may return further capabilities.
665 	 * If we have the extra information store it. For older firmware that
666 	 * does not implement the extended command use the default value.
667 	 */
668 	if (rc == 0 &&
669 	    out_len >= MC_CMD_PTP_OUT_GET_ATTRIBUTES_CAPABILITIES_OFST)
670 		ptp->min_synchronisation_ns =
671 			MCDI_DWORD(outbuf,
672 				   PTP_OUT_GET_ATTRIBUTES_SYNC_WINDOW_MIN);
673 	else
674 		ptp->min_synchronisation_ns = DEFAULT_MIN_SYNCHRONISATION_NS;
675 
676 	if (rc == 0 &&
677 	    out_len >= MC_CMD_PTP_OUT_GET_ATTRIBUTES_LEN)
678 		ptp->capabilities = MCDI_DWORD(outbuf,
679 					PTP_OUT_GET_ATTRIBUTES_CAPABILITIES);
680 	else
681 		ptp->capabilities = 0;
682 
683 	/* Set up the shift for conversion between frequency
684 	 * adjustments in parts-per-billion and the fixed-point
685 	 * fractional ns format that the adapter uses.
686 	 */
687 	if (ptp->capabilities & (1 << MC_CMD_PTP_OUT_GET_ATTRIBUTES_FP44_FREQ_ADJ_LBN))
688 		ptp->adjfreq_ppb_shift = PPB_SHIFT_FP44;
689 	else
690 		ptp->adjfreq_ppb_shift = PPB_SHIFT_FP40;
691 
692 	return 0;
693 }
694 
695 /* Get PTP timestamp corrections */
696 static int efx_ptp_get_timestamp_corrections(struct efx_nic *efx)
697 {
698 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_GET_TIMESTAMP_CORRECTIONS_LEN);
699 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_LEN);
700 	int rc;
701 	size_t out_len;
702 
703 	/* Get the timestamp corrections from the NIC. If this operation is
704 	 * not supported (older NICs) then no correction is required.
705 	 */
706 	MCDI_SET_DWORD(inbuf, PTP_IN_OP,
707 		       MC_CMD_PTP_OP_GET_TIMESTAMP_CORRECTIONS);
708 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
709 
710 	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
711 				outbuf, sizeof(outbuf), &out_len);
712 	if (rc == 0) {
713 		efx->ptp_data->ts_corrections.ptp_tx = MCDI_DWORD(outbuf,
714 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_TRANSMIT);
715 		efx->ptp_data->ts_corrections.ptp_rx = MCDI_DWORD(outbuf,
716 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_RECEIVE);
717 		efx->ptp_data->ts_corrections.pps_out = MCDI_DWORD(outbuf,
718 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_PPS_OUT);
719 		efx->ptp_data->ts_corrections.pps_in = MCDI_DWORD(outbuf,
720 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_PPS_IN);
721 
722 		if (out_len >= MC_CMD_PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_LEN) {
723 			efx->ptp_data->ts_corrections.general_tx = MCDI_DWORD(
724 				outbuf,
725 				PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_GENERAL_TX);
726 			efx->ptp_data->ts_corrections.general_rx = MCDI_DWORD(
727 				outbuf,
728 				PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_GENERAL_RX);
729 		} else {
730 			efx->ptp_data->ts_corrections.general_tx =
731 				efx->ptp_data->ts_corrections.ptp_tx;
732 			efx->ptp_data->ts_corrections.general_rx =
733 				efx->ptp_data->ts_corrections.ptp_rx;
734 		}
735 	} else if (rc == -EINVAL) {
736 		efx->ptp_data->ts_corrections.ptp_tx = 0;
737 		efx->ptp_data->ts_corrections.ptp_rx = 0;
738 		efx->ptp_data->ts_corrections.pps_out = 0;
739 		efx->ptp_data->ts_corrections.pps_in = 0;
740 		efx->ptp_data->ts_corrections.general_tx = 0;
741 		efx->ptp_data->ts_corrections.general_rx = 0;
742 	} else {
743 		efx_mcdi_display_error(efx, MC_CMD_PTP, sizeof(inbuf), outbuf,
744 				       sizeof(outbuf), rc);
745 		return rc;
746 	}
747 
748 	return 0;
749 }
750 
751 /* Enable MCDI PTP support. */
752 static int efx_ptp_enable(struct efx_nic *efx)
753 {
754 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_ENABLE_LEN);
755 	MCDI_DECLARE_BUF_ERR(outbuf);
756 	int rc;
757 
758 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_ENABLE);
759 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
760 	MCDI_SET_DWORD(inbuf, PTP_IN_ENABLE_QUEUE,
761 		       efx->ptp_data->channel ?
762 		       efx->ptp_data->channel->channel : 0);
763 	MCDI_SET_DWORD(inbuf, PTP_IN_ENABLE_MODE, efx->ptp_data->mode);
764 
765 	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
766 				outbuf, sizeof(outbuf), NULL);
767 	rc = (rc == -EALREADY) ? 0 : rc;
768 	if (rc)
769 		efx_mcdi_display_error(efx, MC_CMD_PTP,
770 				       MC_CMD_PTP_IN_ENABLE_LEN,
771 				       outbuf, sizeof(outbuf), rc);
772 	return rc;
773 }
774 
775 /* Disable MCDI PTP support.
776  *
777  * Note that this function should never rely on the presence of ptp_data -
778  * may be called before that exists.
779  */
780 static int efx_ptp_disable(struct efx_nic *efx)
781 {
782 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_DISABLE_LEN);
783 	MCDI_DECLARE_BUF_ERR(outbuf);
784 	int rc;
785 
786 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_DISABLE);
787 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
788 	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
789 				outbuf, sizeof(outbuf), NULL);
790 	rc = (rc == -EALREADY) ? 0 : rc;
791 	/* If we get ENOSYS, the NIC doesn't support PTP, and thus this function
792 	 * should only have been called during probe.
793 	 */
794 	if (rc == -ENOSYS || rc == -EPERM)
795 		netif_info(efx, probe, efx->net_dev, "no PTP support\n");
796 	else if (rc)
797 		efx_mcdi_display_error(efx, MC_CMD_PTP,
798 				       MC_CMD_PTP_IN_DISABLE_LEN,
799 				       outbuf, sizeof(outbuf), rc);
800 	return rc;
801 }
802 
803 static void efx_ptp_deliver_rx_queue(struct sk_buff_head *q)
804 {
805 	struct sk_buff *skb;
806 
807 	while ((skb = skb_dequeue(q))) {
808 		local_bh_disable();
809 		netif_receive_skb(skb);
810 		local_bh_enable();
811 	}
812 }
813 
814 static void efx_ptp_handle_no_channel(struct efx_nic *efx)
815 {
816 	netif_err(efx, drv, efx->net_dev,
817 		  "ERROR: PTP requires MSI-X and 1 additional interrupt"
818 		  "vector. PTP disabled\n");
819 }
820 
821 /* Repeatedly send the host time to the MC which will capture the hardware
822  * time.
823  */
824 static void efx_ptp_send_times(struct efx_nic *efx,
825 			       struct pps_event_time *last_time)
826 {
827 	struct pps_event_time now;
828 	struct timespec64 limit;
829 	struct efx_ptp_data *ptp = efx->ptp_data;
830 	int *mc_running = ptp->start.addr;
831 
832 	pps_get_ts(&now);
833 	limit = now.ts_real;
834 	timespec64_add_ns(&limit, SYNCHRONISE_PERIOD_NS);
835 
836 	/* Write host time for specified period or until MC is done */
837 	while ((timespec64_compare(&now.ts_real, &limit) < 0) &&
838 	       READ_ONCE(*mc_running)) {
839 		struct timespec64 update_time;
840 		unsigned int host_time;
841 
842 		/* Don't update continuously to avoid saturating the PCIe bus */
843 		update_time = now.ts_real;
844 		timespec64_add_ns(&update_time, SYNCHRONISATION_GRANULARITY_NS);
845 		do {
846 			pps_get_ts(&now);
847 		} while ((timespec64_compare(&now.ts_real, &update_time) < 0) &&
848 			 READ_ONCE(*mc_running));
849 
850 		/* Synchronise NIC with single word of time only */
851 		host_time = (now.ts_real.tv_sec << MC_NANOSECOND_BITS |
852 			     now.ts_real.tv_nsec);
853 		/* Update host time in NIC memory */
854 		efx->type->ptp_write_host_time(efx, host_time);
855 	}
856 	*last_time = now;
857 }
858 
859 /* Read a timeset from the MC's results and partial process. */
860 static void efx_ptp_read_timeset(MCDI_DECLARE_STRUCT_PTR(data),
861 				 struct efx_ptp_timeset *timeset)
862 {
863 	unsigned start_ns, end_ns;
864 
865 	timeset->host_start = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTSTART);
866 	timeset->major = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_MAJOR);
867 	timeset->minor = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_MINOR);
868 	timeset->host_end = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTEND),
869 	timeset->wait = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_WAITNS);
870 
871 	/* Ignore seconds */
872 	start_ns = timeset->host_start & MC_NANOSECOND_MASK;
873 	end_ns = timeset->host_end & MC_NANOSECOND_MASK;
874 	/* Allow for rollover */
875 	if (end_ns < start_ns)
876 		end_ns += NSEC_PER_SEC;
877 	/* Determine duration of operation */
878 	timeset->window = end_ns - start_ns;
879 }
880 
881 /* Process times received from MC.
882  *
883  * Extract times from returned results, and establish the minimum value
884  * seen.  The minimum value represents the "best" possible time and events
885  * too much greater than this are rejected - the machine is, perhaps, too
886  * busy. A number of readings are taken so that, hopefully, at least one good
887  * synchronisation will be seen in the results.
888  */
889 static int
890 efx_ptp_process_times(struct efx_nic *efx, MCDI_DECLARE_STRUCT_PTR(synch_buf),
891 		      size_t response_length,
892 		      const struct pps_event_time *last_time)
893 {
894 	unsigned number_readings =
895 		MCDI_VAR_ARRAY_LEN(response_length,
896 				   PTP_OUT_SYNCHRONIZE_TIMESET);
897 	unsigned i;
898 	unsigned ngood = 0;
899 	unsigned last_good = 0;
900 	struct efx_ptp_data *ptp = efx->ptp_data;
901 	u32 last_sec;
902 	u32 start_sec;
903 	struct timespec64 delta;
904 	ktime_t mc_time;
905 
906 	if (number_readings == 0)
907 		return -EAGAIN;
908 
909 	/* Read the set of results and find the last good host-MC
910 	 * synchronization result. The MC times when it finishes reading the
911 	 * host time so the corrected window time should be fairly constant
912 	 * for a given platform. Increment stats for any results that appear
913 	 * to be erroneous.
914 	 */
915 	for (i = 0; i < number_readings; i++) {
916 		s32 window, corrected;
917 		struct timespec64 wait;
918 
919 		efx_ptp_read_timeset(
920 			MCDI_ARRAY_STRUCT_PTR(synch_buf,
921 					      PTP_OUT_SYNCHRONIZE_TIMESET, i),
922 			&ptp->timeset[i]);
923 
924 		wait = ktime_to_timespec64(
925 			ptp->nic_to_kernel_time(0, ptp->timeset[i].wait, 0));
926 		window = ptp->timeset[i].window;
927 		corrected = window - wait.tv_nsec;
928 
929 		/* We expect the uncorrected synchronization window to be at
930 		 * least as large as the interval between host start and end
931 		 * times. If it is smaller than this then this is mostly likely
932 		 * to be a consequence of the host's time being adjusted.
933 		 * Check that the corrected sync window is in a reasonable
934 		 * range. If it is out of range it is likely to be because an
935 		 * interrupt or other delay occurred between reading the system
936 		 * time and writing it to MC memory.
937 		 */
938 		if (window < SYNCHRONISATION_GRANULARITY_NS) {
939 			++ptp->invalid_sync_windows;
940 		} else if (corrected >= MAX_SYNCHRONISATION_NS) {
941 			++ptp->oversize_sync_windows;
942 		} else if (corrected < ptp->min_synchronisation_ns) {
943 			++ptp->undersize_sync_windows;
944 		} else {
945 			ngood++;
946 			last_good = i;
947 		}
948 	}
949 
950 	if (ngood == 0) {
951 		netif_warn(efx, drv, efx->net_dev,
952 			   "PTP no suitable synchronisations\n");
953 		return -EAGAIN;
954 	}
955 
956 	/* Calculate delay from last good sync (host time) to last_time.
957 	 * It is possible that the seconds rolled over between taking
958 	 * the start reading and the last value written by the host.  The
959 	 * timescales are such that a gap of more than one second is never
960 	 * expected.  delta is *not* normalised.
961 	 */
962 	start_sec = ptp->timeset[last_good].host_start >> MC_NANOSECOND_BITS;
963 	last_sec = last_time->ts_real.tv_sec & MC_SECOND_MASK;
964 	if (start_sec != last_sec &&
965 	    ((start_sec + 1) & MC_SECOND_MASK) != last_sec) {
966 		netif_warn(efx, hw, efx->net_dev,
967 			   "PTP bad synchronisation seconds\n");
968 		return -EAGAIN;
969 	}
970 	delta.tv_sec = (last_sec - start_sec) & 1;
971 	delta.tv_nsec =
972 		last_time->ts_real.tv_nsec -
973 		(ptp->timeset[last_good].host_start & MC_NANOSECOND_MASK);
974 
975 	/* Convert the NIC time at last good sync into kernel time.
976 	 * No correction is required - this time is the output of a
977 	 * firmware process.
978 	 */
979 	mc_time = ptp->nic_to_kernel_time(ptp->timeset[last_good].major,
980 					  ptp->timeset[last_good].minor, 0);
981 
982 	/* Calculate delay from NIC top of second to last_time */
983 	delta.tv_nsec += ktime_to_timespec64(mc_time).tv_nsec;
984 
985 	/* Set PPS timestamp to match NIC top of second */
986 	ptp->host_time_pps = *last_time;
987 	pps_sub_ts(&ptp->host_time_pps, delta);
988 
989 	return 0;
990 }
991 
992 /* Synchronize times between the host and the MC */
993 static int efx_ptp_synchronize(struct efx_nic *efx, unsigned int num_readings)
994 {
995 	struct efx_ptp_data *ptp = efx->ptp_data;
996 	MCDI_DECLARE_BUF(synch_buf, MC_CMD_PTP_OUT_SYNCHRONIZE_LENMAX);
997 	size_t response_length;
998 	int rc;
999 	unsigned long timeout;
1000 	struct pps_event_time last_time = {};
1001 	unsigned int loops = 0;
1002 	int *start = ptp->start.addr;
1003 
1004 	MCDI_SET_DWORD(synch_buf, PTP_IN_OP, MC_CMD_PTP_OP_SYNCHRONIZE);
1005 	MCDI_SET_DWORD(synch_buf, PTP_IN_PERIPH_ID, 0);
1006 	MCDI_SET_DWORD(synch_buf, PTP_IN_SYNCHRONIZE_NUMTIMESETS,
1007 		       num_readings);
1008 	MCDI_SET_QWORD(synch_buf, PTP_IN_SYNCHRONIZE_START_ADDR,
1009 		       ptp->start.dma_addr);
1010 
1011 	/* Clear flag that signals MC ready */
1012 	WRITE_ONCE(*start, 0);
1013 	rc = efx_mcdi_rpc_start(efx, MC_CMD_PTP, synch_buf,
1014 				MC_CMD_PTP_IN_SYNCHRONIZE_LEN);
1015 	EFX_WARN_ON_ONCE_PARANOID(rc);
1016 
1017 	/* Wait for start from MCDI (or timeout) */
1018 	timeout = jiffies + msecs_to_jiffies(MAX_SYNCHRONISE_WAIT_MS);
1019 	while (!READ_ONCE(*start) && (time_before(jiffies, timeout))) {
1020 		udelay(20);	/* Usually start MCDI execution quickly */
1021 		loops++;
1022 	}
1023 
1024 	if (loops <= 1)
1025 		++ptp->fast_syncs;
1026 	if (!time_before(jiffies, timeout))
1027 		++ptp->sync_timeouts;
1028 
1029 	if (READ_ONCE(*start))
1030 		efx_ptp_send_times(efx, &last_time);
1031 
1032 	/* Collect results */
1033 	rc = efx_mcdi_rpc_finish(efx, MC_CMD_PTP,
1034 				 MC_CMD_PTP_IN_SYNCHRONIZE_LEN,
1035 				 synch_buf, sizeof(synch_buf),
1036 				 &response_length);
1037 	if (rc == 0) {
1038 		rc = efx_ptp_process_times(efx, synch_buf, response_length,
1039 					   &last_time);
1040 		if (rc == 0)
1041 			++ptp->good_syncs;
1042 		else
1043 			++ptp->no_time_syncs;
1044 	}
1045 
1046 	/* Increment the bad syncs counter if the synchronize fails, whatever
1047 	 * the reason.
1048 	 */
1049 	if (rc != 0)
1050 		++ptp->bad_syncs;
1051 
1052 	return rc;
1053 }
1054 
1055 /* Transmit a PTP packet via the dedicated hardware timestamped queue. */
1056 static void efx_ptp_xmit_skb_queue(struct efx_nic *efx, struct sk_buff *skb)
1057 {
1058 	struct efx_ptp_data *ptp_data = efx->ptp_data;
1059 	struct efx_tx_queue *tx_queue;
1060 	u8 type = skb->ip_summed == CHECKSUM_PARTIAL ? EFX_TXQ_TYPE_OFFLOAD : 0;
1061 
1062 	tx_queue = &ptp_data->channel->tx_queue[type];
1063 	if (tx_queue && tx_queue->timestamping) {
1064 		efx_enqueue_skb(tx_queue, skb);
1065 	} else {
1066 		WARN_ONCE(1, "PTP channel has no timestamped tx queue\n");
1067 		dev_kfree_skb_any(skb);
1068 	}
1069 }
1070 
1071 /* Transmit a PTP packet, via the MCDI interface, to the wire. */
1072 static void efx_ptp_xmit_skb_mc(struct efx_nic *efx, struct sk_buff *skb)
1073 {
1074 	struct efx_ptp_data *ptp_data = efx->ptp_data;
1075 	struct skb_shared_hwtstamps timestamps;
1076 	int rc = -EIO;
1077 	MCDI_DECLARE_BUF(txtime, MC_CMD_PTP_OUT_TRANSMIT_LEN);
1078 	size_t len;
1079 
1080 	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_OP, MC_CMD_PTP_OP_TRANSMIT);
1081 	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_PERIPH_ID, 0);
1082 	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_TRANSMIT_LENGTH, skb->len);
1083 	if (skb_shinfo(skb)->nr_frags != 0) {
1084 		rc = skb_linearize(skb);
1085 		if (rc != 0)
1086 			goto fail;
1087 	}
1088 
1089 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
1090 		rc = skb_checksum_help(skb);
1091 		if (rc != 0)
1092 			goto fail;
1093 	}
1094 	skb_copy_from_linear_data(skb,
1095 				  MCDI_PTR(ptp_data->txbuf,
1096 					   PTP_IN_TRANSMIT_PACKET),
1097 				  skb->len);
1098 	rc = efx_mcdi_rpc(efx, MC_CMD_PTP,
1099 			  ptp_data->txbuf, MC_CMD_PTP_IN_TRANSMIT_LEN(skb->len),
1100 			  txtime, sizeof(txtime), &len);
1101 	if (rc != 0)
1102 		goto fail;
1103 
1104 	memset(&timestamps, 0, sizeof(timestamps));
1105 	timestamps.hwtstamp = ptp_data->nic_to_kernel_time(
1106 		MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_MAJOR),
1107 		MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_MINOR),
1108 		ptp_data->ts_corrections.ptp_tx);
1109 
1110 	skb_tstamp_tx(skb, &timestamps);
1111 
1112 	rc = 0;
1113 
1114 fail:
1115 	dev_kfree_skb_any(skb);
1116 
1117 	return;
1118 }
1119 
1120 static void efx_ptp_drop_time_expired_events(struct efx_nic *efx)
1121 {
1122 	struct efx_ptp_data *ptp = efx->ptp_data;
1123 	struct list_head *cursor;
1124 	struct list_head *next;
1125 
1126 	if (ptp->rx_ts_inline)
1127 		return;
1128 
1129 	/* Drop time-expired events */
1130 	spin_lock_bh(&ptp->evt_lock);
1131 	if (!list_empty(&ptp->evt_list)) {
1132 		list_for_each_safe(cursor, next, &ptp->evt_list) {
1133 			struct efx_ptp_event_rx *evt;
1134 
1135 			evt = list_entry(cursor, struct efx_ptp_event_rx,
1136 					 link);
1137 			if (time_after(jiffies, evt->expiry)) {
1138 				list_move(&evt->link, &ptp->evt_free_list);
1139 				netif_warn(efx, hw, efx->net_dev,
1140 					   "PTP rx event dropped\n");
1141 			}
1142 		}
1143 	}
1144 	spin_unlock_bh(&ptp->evt_lock);
1145 }
1146 
1147 static enum ptp_packet_state efx_ptp_match_rx(struct efx_nic *efx,
1148 					      struct sk_buff *skb)
1149 {
1150 	struct efx_ptp_data *ptp = efx->ptp_data;
1151 	bool evts_waiting;
1152 	struct list_head *cursor;
1153 	struct list_head *next;
1154 	struct efx_ptp_match *match;
1155 	enum ptp_packet_state rc = PTP_PACKET_STATE_UNMATCHED;
1156 
1157 	WARN_ON_ONCE(ptp->rx_ts_inline);
1158 
1159 	spin_lock_bh(&ptp->evt_lock);
1160 	evts_waiting = !list_empty(&ptp->evt_list);
1161 	spin_unlock_bh(&ptp->evt_lock);
1162 
1163 	if (!evts_waiting)
1164 		return PTP_PACKET_STATE_UNMATCHED;
1165 
1166 	match = (struct efx_ptp_match *)skb->cb;
1167 	/* Look for a matching timestamp in the event queue */
1168 	spin_lock_bh(&ptp->evt_lock);
1169 	list_for_each_safe(cursor, next, &ptp->evt_list) {
1170 		struct efx_ptp_event_rx *evt;
1171 
1172 		evt = list_entry(cursor, struct efx_ptp_event_rx, link);
1173 		if ((evt->seq0 == match->words[0]) &&
1174 		    (evt->seq1 == match->words[1])) {
1175 			struct skb_shared_hwtstamps *timestamps;
1176 
1177 			/* Match - add in hardware timestamp */
1178 			timestamps = skb_hwtstamps(skb);
1179 			timestamps->hwtstamp = evt->hwtimestamp;
1180 
1181 			match->state = PTP_PACKET_STATE_MATCHED;
1182 			rc = PTP_PACKET_STATE_MATCHED;
1183 			list_move(&evt->link, &ptp->evt_free_list);
1184 			break;
1185 		}
1186 	}
1187 	spin_unlock_bh(&ptp->evt_lock);
1188 
1189 	return rc;
1190 }
1191 
1192 /* Process any queued receive events and corresponding packets
1193  *
1194  * q is returned with all the packets that are ready for delivery.
1195  */
1196 static void efx_ptp_process_events(struct efx_nic *efx, struct sk_buff_head *q)
1197 {
1198 	struct efx_ptp_data *ptp = efx->ptp_data;
1199 	struct sk_buff *skb;
1200 
1201 	while ((skb = skb_dequeue(&ptp->rxq))) {
1202 		struct efx_ptp_match *match;
1203 
1204 		match = (struct efx_ptp_match *)skb->cb;
1205 		if (match->state == PTP_PACKET_STATE_MATCH_UNWANTED) {
1206 			__skb_queue_tail(q, skb);
1207 		} else if (efx_ptp_match_rx(efx, skb) ==
1208 			   PTP_PACKET_STATE_MATCHED) {
1209 			__skb_queue_tail(q, skb);
1210 		} else if (time_after(jiffies, match->expiry)) {
1211 			match->state = PTP_PACKET_STATE_TIMED_OUT;
1212 			++ptp->rx_no_timestamp;
1213 			__skb_queue_tail(q, skb);
1214 		} else {
1215 			/* Replace unprocessed entry and stop */
1216 			skb_queue_head(&ptp->rxq, skb);
1217 			break;
1218 		}
1219 	}
1220 }
1221 
1222 /* Complete processing of a received packet */
1223 static inline void efx_ptp_process_rx(struct efx_nic *efx, struct sk_buff *skb)
1224 {
1225 	local_bh_disable();
1226 	netif_receive_skb(skb);
1227 	local_bh_enable();
1228 }
1229 
1230 static void efx_ptp_remove_multicast_filters(struct efx_nic *efx)
1231 {
1232 	struct efx_ptp_data *ptp = efx->ptp_data;
1233 
1234 	if (ptp->rxfilter_installed) {
1235 		efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED,
1236 					  ptp->rxfilter_general);
1237 		efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED,
1238 					  ptp->rxfilter_event);
1239 		ptp->rxfilter_installed = false;
1240 	}
1241 }
1242 
1243 static int efx_ptp_insert_multicast_filters(struct efx_nic *efx)
1244 {
1245 	struct efx_ptp_data *ptp = efx->ptp_data;
1246 	struct efx_filter_spec rxfilter;
1247 	int rc;
1248 
1249 	if (!ptp->channel || ptp->rxfilter_installed)
1250 		return 0;
1251 
1252 	/* Must filter on both event and general ports to ensure
1253 	 * that there is no packet re-ordering.
1254 	 */
1255 	efx_filter_init_rx(&rxfilter, EFX_FILTER_PRI_REQUIRED, 0,
1256 			   efx_rx_queue_index(
1257 				   efx_channel_get_rx_queue(ptp->channel)));
1258 	rc = efx_filter_set_ipv4_local(&rxfilter, IPPROTO_UDP,
1259 				       htonl(PTP_ADDRESS),
1260 				       htons(PTP_EVENT_PORT));
1261 	if (rc != 0)
1262 		return rc;
1263 
1264 	rc = efx_filter_insert_filter(efx, &rxfilter, true);
1265 	if (rc < 0)
1266 		return rc;
1267 	ptp->rxfilter_event = rc;
1268 
1269 	efx_filter_init_rx(&rxfilter, EFX_FILTER_PRI_REQUIRED, 0,
1270 			   efx_rx_queue_index(
1271 				   efx_channel_get_rx_queue(ptp->channel)));
1272 	rc = efx_filter_set_ipv4_local(&rxfilter, IPPROTO_UDP,
1273 				       htonl(PTP_ADDRESS),
1274 				       htons(PTP_GENERAL_PORT));
1275 	if (rc != 0)
1276 		goto fail;
1277 
1278 	rc = efx_filter_insert_filter(efx, &rxfilter, true);
1279 	if (rc < 0)
1280 		goto fail;
1281 	ptp->rxfilter_general = rc;
1282 
1283 	ptp->rxfilter_installed = true;
1284 	return 0;
1285 
1286 fail:
1287 	efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED,
1288 				  ptp->rxfilter_event);
1289 	return rc;
1290 }
1291 
1292 static int efx_ptp_start(struct efx_nic *efx)
1293 {
1294 	struct efx_ptp_data *ptp = efx->ptp_data;
1295 	int rc;
1296 
1297 	ptp->reset_required = false;
1298 
1299 	rc = efx_ptp_insert_multicast_filters(efx);
1300 	if (rc)
1301 		return rc;
1302 
1303 	rc = efx_ptp_enable(efx);
1304 	if (rc != 0)
1305 		goto fail;
1306 
1307 	ptp->evt_frag_idx = 0;
1308 	ptp->current_adjfreq = 0;
1309 
1310 	return 0;
1311 
1312 fail:
1313 	efx_ptp_remove_multicast_filters(efx);
1314 	return rc;
1315 }
1316 
1317 static int efx_ptp_stop(struct efx_nic *efx)
1318 {
1319 	struct efx_ptp_data *ptp = efx->ptp_data;
1320 	struct list_head *cursor;
1321 	struct list_head *next;
1322 	int rc;
1323 
1324 	if (ptp == NULL)
1325 		return 0;
1326 
1327 	rc = efx_ptp_disable(efx);
1328 
1329 	efx_ptp_remove_multicast_filters(efx);
1330 
1331 	/* Make sure RX packets are really delivered */
1332 	efx_ptp_deliver_rx_queue(&efx->ptp_data->rxq);
1333 	skb_queue_purge(&efx->ptp_data->txq);
1334 
1335 	/* Drop any pending receive events */
1336 	spin_lock_bh(&efx->ptp_data->evt_lock);
1337 	list_for_each_safe(cursor, next, &efx->ptp_data->evt_list) {
1338 		list_move(cursor, &efx->ptp_data->evt_free_list);
1339 	}
1340 	spin_unlock_bh(&efx->ptp_data->evt_lock);
1341 
1342 	return rc;
1343 }
1344 
1345 static int efx_ptp_restart(struct efx_nic *efx)
1346 {
1347 	if (efx->ptp_data && efx->ptp_data->enabled)
1348 		return efx_ptp_start(efx);
1349 	return 0;
1350 }
1351 
1352 static void efx_ptp_pps_worker(struct work_struct *work)
1353 {
1354 	struct efx_ptp_data *ptp =
1355 		container_of(work, struct efx_ptp_data, pps_work);
1356 	struct efx_nic *efx = ptp->efx;
1357 	struct ptp_clock_event ptp_evt;
1358 
1359 	if (efx_ptp_synchronize(efx, PTP_SYNC_ATTEMPTS))
1360 		return;
1361 
1362 	ptp_evt.type = PTP_CLOCK_PPSUSR;
1363 	ptp_evt.pps_times = ptp->host_time_pps;
1364 	ptp_clock_event(ptp->phc_clock, &ptp_evt);
1365 }
1366 
1367 static void efx_ptp_worker(struct work_struct *work)
1368 {
1369 	struct efx_ptp_data *ptp_data =
1370 		container_of(work, struct efx_ptp_data, work);
1371 	struct efx_nic *efx = ptp_data->efx;
1372 	struct sk_buff *skb;
1373 	struct sk_buff_head tempq;
1374 
1375 	if (ptp_data->reset_required) {
1376 		efx_ptp_stop(efx);
1377 		efx_ptp_start(efx);
1378 		return;
1379 	}
1380 
1381 	efx_ptp_drop_time_expired_events(efx);
1382 
1383 	__skb_queue_head_init(&tempq);
1384 	efx_ptp_process_events(efx, &tempq);
1385 
1386 	while ((skb = skb_dequeue(&ptp_data->txq)))
1387 		ptp_data->xmit_skb(efx, skb);
1388 
1389 	while ((skb = __skb_dequeue(&tempq)))
1390 		efx_ptp_process_rx(efx, skb);
1391 }
1392 
1393 static const struct ptp_clock_info efx_phc_clock_info = {
1394 	.owner		= THIS_MODULE,
1395 	.name		= "sfc",
1396 	.max_adj	= MAX_PPB,
1397 	.n_alarm	= 0,
1398 	.n_ext_ts	= 0,
1399 	.n_per_out	= 0,
1400 	.n_pins		= 0,
1401 	.pps		= 1,
1402 	.adjfreq	= efx_phc_adjfreq,
1403 	.adjtime	= efx_phc_adjtime,
1404 	.gettime64	= efx_phc_gettime,
1405 	.settime64	= efx_phc_settime,
1406 	.enable		= efx_phc_enable,
1407 };
1408 
1409 /* Initialise PTP state. */
1410 int efx_ptp_probe(struct efx_nic *efx, struct efx_channel *channel)
1411 {
1412 	struct efx_ptp_data *ptp;
1413 	int rc = 0;
1414 	unsigned int pos;
1415 
1416 	ptp = kzalloc(sizeof(struct efx_ptp_data), GFP_KERNEL);
1417 	efx->ptp_data = ptp;
1418 	if (!efx->ptp_data)
1419 		return -ENOMEM;
1420 
1421 	ptp->efx = efx;
1422 	ptp->channel = channel;
1423 	ptp->rx_ts_inline = efx_nic_rev(efx) >= EFX_REV_HUNT_A0;
1424 
1425 	rc = efx_nic_alloc_buffer(efx, &ptp->start, sizeof(int), GFP_KERNEL);
1426 	if (rc != 0)
1427 		goto fail1;
1428 
1429 	skb_queue_head_init(&ptp->rxq);
1430 	skb_queue_head_init(&ptp->txq);
1431 	ptp->workwq = create_singlethread_workqueue("sfc_ptp");
1432 	if (!ptp->workwq) {
1433 		rc = -ENOMEM;
1434 		goto fail2;
1435 	}
1436 
1437 	if (efx_ptp_use_mac_tx_timestamps(efx)) {
1438 		ptp->xmit_skb = efx_ptp_xmit_skb_queue;
1439 		/* Request sync events on this channel. */
1440 		channel->sync_events_state = SYNC_EVENTS_QUIESCENT;
1441 	} else {
1442 		ptp->xmit_skb = efx_ptp_xmit_skb_mc;
1443 	}
1444 
1445 	INIT_WORK(&ptp->work, efx_ptp_worker);
1446 	ptp->config.flags = 0;
1447 	ptp->config.tx_type = HWTSTAMP_TX_OFF;
1448 	ptp->config.rx_filter = HWTSTAMP_FILTER_NONE;
1449 	INIT_LIST_HEAD(&ptp->evt_list);
1450 	INIT_LIST_HEAD(&ptp->evt_free_list);
1451 	spin_lock_init(&ptp->evt_lock);
1452 	for (pos = 0; pos < MAX_RECEIVE_EVENTS; pos++)
1453 		list_add(&ptp->rx_evts[pos].link, &ptp->evt_free_list);
1454 
1455 	/* Get the NIC PTP attributes and set up time conversions */
1456 	rc = efx_ptp_get_attributes(efx);
1457 	if (rc < 0)
1458 		goto fail3;
1459 
1460 	/* Get the timestamp corrections */
1461 	rc = efx_ptp_get_timestamp_corrections(efx);
1462 	if (rc < 0)
1463 		goto fail3;
1464 
1465 	if (efx->mcdi->fn_flags &
1466 	    (1 << MC_CMD_DRV_ATTACH_EXT_OUT_FLAG_PRIMARY)) {
1467 		ptp->phc_clock_info = efx_phc_clock_info;
1468 		ptp->phc_clock = ptp_clock_register(&ptp->phc_clock_info,
1469 						    &efx->pci_dev->dev);
1470 		if (IS_ERR(ptp->phc_clock)) {
1471 			rc = PTR_ERR(ptp->phc_clock);
1472 			goto fail3;
1473 		} else if (ptp->phc_clock) {
1474 			INIT_WORK(&ptp->pps_work, efx_ptp_pps_worker);
1475 			ptp->pps_workwq = create_singlethread_workqueue("sfc_pps");
1476 			if (!ptp->pps_workwq) {
1477 				rc = -ENOMEM;
1478 				goto fail4;
1479 			}
1480 		}
1481 	}
1482 	ptp->nic_ts_enabled = false;
1483 
1484 	return 0;
1485 fail4:
1486 	ptp_clock_unregister(efx->ptp_data->phc_clock);
1487 
1488 fail3:
1489 	destroy_workqueue(efx->ptp_data->workwq);
1490 
1491 fail2:
1492 	efx_nic_free_buffer(efx, &ptp->start);
1493 
1494 fail1:
1495 	kfree(efx->ptp_data);
1496 	efx->ptp_data = NULL;
1497 
1498 	return rc;
1499 }
1500 
1501 /* Initialise PTP channel.
1502  *
1503  * Setting core_index to zero causes the queue to be initialised and doesn't
1504  * overlap with 'rxq0' because ptp.c doesn't use skb_record_rx_queue.
1505  */
1506 static int efx_ptp_probe_channel(struct efx_channel *channel)
1507 {
1508 	struct efx_nic *efx = channel->efx;
1509 	int rc;
1510 
1511 	channel->irq_moderation_us = 0;
1512 	channel->rx_queue.core_index = 0;
1513 
1514 	rc = efx_ptp_probe(efx, channel);
1515 	/* Failure to probe PTP is not fatal; this channel will just not be
1516 	 * used for anything.
1517 	 * In the case of EPERM, efx_ptp_probe will print its own message (in
1518 	 * efx_ptp_get_attributes()), so we don't need to.
1519 	 */
1520 	if (rc && rc != -EPERM)
1521 		netif_warn(efx, drv, efx->net_dev,
1522 			   "Failed to probe PTP, rc=%d\n", rc);
1523 	return 0;
1524 }
1525 
1526 void efx_ptp_remove(struct efx_nic *efx)
1527 {
1528 	if (!efx->ptp_data)
1529 		return;
1530 
1531 	(void)efx_ptp_disable(efx);
1532 
1533 	cancel_work_sync(&efx->ptp_data->work);
1534 	cancel_work_sync(&efx->ptp_data->pps_work);
1535 
1536 	skb_queue_purge(&efx->ptp_data->rxq);
1537 	skb_queue_purge(&efx->ptp_data->txq);
1538 
1539 	if (efx->ptp_data->phc_clock) {
1540 		destroy_workqueue(efx->ptp_data->pps_workwq);
1541 		ptp_clock_unregister(efx->ptp_data->phc_clock);
1542 	}
1543 
1544 	destroy_workqueue(efx->ptp_data->workwq);
1545 
1546 	efx_nic_free_buffer(efx, &efx->ptp_data->start);
1547 	kfree(efx->ptp_data);
1548 	efx->ptp_data = NULL;
1549 }
1550 
1551 static void efx_ptp_remove_channel(struct efx_channel *channel)
1552 {
1553 	efx_ptp_remove(channel->efx);
1554 }
1555 
1556 static void efx_ptp_get_channel_name(struct efx_channel *channel,
1557 				     char *buf, size_t len)
1558 {
1559 	snprintf(buf, len, "%s-ptp", channel->efx->name);
1560 }
1561 
1562 /* Determine whether this packet should be processed by the PTP module
1563  * or transmitted conventionally.
1564  */
1565 bool efx_ptp_is_ptp_tx(struct efx_nic *efx, struct sk_buff *skb)
1566 {
1567 	return efx->ptp_data &&
1568 		efx->ptp_data->enabled &&
1569 		skb->len >= PTP_MIN_LENGTH &&
1570 		skb->len <= MC_CMD_PTP_IN_TRANSMIT_PACKET_MAXNUM &&
1571 		likely(skb->protocol == htons(ETH_P_IP)) &&
1572 		skb_transport_header_was_set(skb) &&
1573 		skb_network_header_len(skb) >= sizeof(struct iphdr) &&
1574 		ip_hdr(skb)->protocol == IPPROTO_UDP &&
1575 		skb_headlen(skb) >=
1576 		skb_transport_offset(skb) + sizeof(struct udphdr) &&
1577 		udp_hdr(skb)->dest == htons(PTP_EVENT_PORT);
1578 }
1579 
1580 /* Receive a PTP packet.  Packets are queued until the arrival of
1581  * the receive timestamp from the MC - this will probably occur after the
1582  * packet arrival because of the processing in the MC.
1583  */
1584 static bool efx_ptp_rx(struct efx_channel *channel, struct sk_buff *skb)
1585 {
1586 	struct efx_nic *efx = channel->efx;
1587 	struct efx_ptp_data *ptp = efx->ptp_data;
1588 	struct efx_ptp_match *match = (struct efx_ptp_match *)skb->cb;
1589 	u8 *match_data_012, *match_data_345;
1590 	unsigned int version;
1591 	u8 *data;
1592 
1593 	match->expiry = jiffies + msecs_to_jiffies(PKT_EVENT_LIFETIME_MS);
1594 
1595 	/* Correct version? */
1596 	if (ptp->mode == MC_CMD_PTP_MODE_V1) {
1597 		if (!pskb_may_pull(skb, PTP_V1_MIN_LENGTH)) {
1598 			return false;
1599 		}
1600 		data = skb->data;
1601 		version = ntohs(*(__be16 *)&data[PTP_V1_VERSION_OFFSET]);
1602 		if (version != PTP_VERSION_V1) {
1603 			return false;
1604 		}
1605 
1606 		/* PTP V1 uses all six bytes of the UUID to match the packet
1607 		 * to the timestamp
1608 		 */
1609 		match_data_012 = data + PTP_V1_UUID_OFFSET;
1610 		match_data_345 = data + PTP_V1_UUID_OFFSET + 3;
1611 	} else {
1612 		if (!pskb_may_pull(skb, PTP_V2_MIN_LENGTH)) {
1613 			return false;
1614 		}
1615 		data = skb->data;
1616 		version = data[PTP_V2_VERSION_OFFSET];
1617 		if ((version & PTP_VERSION_V2_MASK) != PTP_VERSION_V2) {
1618 			return false;
1619 		}
1620 
1621 		/* The original V2 implementation uses bytes 2-7 of
1622 		 * the UUID to match the packet to the timestamp. This
1623 		 * discards two of the bytes of the MAC address used
1624 		 * to create the UUID (SF bug 33070).  The PTP V2
1625 		 * enhanced mode fixes this issue and uses bytes 0-2
1626 		 * and byte 5-7 of the UUID.
1627 		 */
1628 		match_data_345 = data + PTP_V2_UUID_OFFSET + 5;
1629 		if (ptp->mode == MC_CMD_PTP_MODE_V2) {
1630 			match_data_012 = data + PTP_V2_UUID_OFFSET + 2;
1631 		} else {
1632 			match_data_012 = data + PTP_V2_UUID_OFFSET + 0;
1633 			BUG_ON(ptp->mode != MC_CMD_PTP_MODE_V2_ENHANCED);
1634 		}
1635 	}
1636 
1637 	/* Does this packet require timestamping? */
1638 	if (ntohs(*(__be16 *)&data[PTP_DPORT_OFFSET]) == PTP_EVENT_PORT) {
1639 		match->state = PTP_PACKET_STATE_UNMATCHED;
1640 
1641 		/* We expect the sequence number to be in the same position in
1642 		 * the packet for PTP V1 and V2
1643 		 */
1644 		BUILD_BUG_ON(PTP_V1_SEQUENCE_OFFSET != PTP_V2_SEQUENCE_OFFSET);
1645 		BUILD_BUG_ON(PTP_V1_SEQUENCE_LENGTH != PTP_V2_SEQUENCE_LENGTH);
1646 
1647 		/* Extract UUID/Sequence information */
1648 		match->words[0] = (match_data_012[0]         |
1649 				   (match_data_012[1] << 8)  |
1650 				   (match_data_012[2] << 16) |
1651 				   (match_data_345[0] << 24));
1652 		match->words[1] = (match_data_345[1]         |
1653 				   (match_data_345[2] << 8)  |
1654 				   (data[PTP_V1_SEQUENCE_OFFSET +
1655 					 PTP_V1_SEQUENCE_LENGTH - 1] <<
1656 				    16));
1657 	} else {
1658 		match->state = PTP_PACKET_STATE_MATCH_UNWANTED;
1659 	}
1660 
1661 	skb_queue_tail(&ptp->rxq, skb);
1662 	queue_work(ptp->workwq, &ptp->work);
1663 
1664 	return true;
1665 }
1666 
1667 /* Transmit a PTP packet.  This has to be transmitted by the MC
1668  * itself, through an MCDI call.  MCDI calls aren't permitted
1669  * in the transmit path so defer the actual transmission to a suitable worker.
1670  */
1671 int efx_ptp_tx(struct efx_nic *efx, struct sk_buff *skb)
1672 {
1673 	struct efx_ptp_data *ptp = efx->ptp_data;
1674 
1675 	skb_queue_tail(&ptp->txq, skb);
1676 
1677 	if ((udp_hdr(skb)->dest == htons(PTP_EVENT_PORT)) &&
1678 	    (skb->len <= MC_CMD_PTP_IN_TRANSMIT_PACKET_MAXNUM))
1679 		efx_xmit_hwtstamp_pending(skb);
1680 	queue_work(ptp->workwq, &ptp->work);
1681 
1682 	return NETDEV_TX_OK;
1683 }
1684 
1685 int efx_ptp_get_mode(struct efx_nic *efx)
1686 {
1687 	return efx->ptp_data->mode;
1688 }
1689 
1690 int efx_ptp_change_mode(struct efx_nic *efx, bool enable_wanted,
1691 			unsigned int new_mode)
1692 {
1693 	if ((enable_wanted != efx->ptp_data->enabled) ||
1694 	    (enable_wanted && (efx->ptp_data->mode != new_mode))) {
1695 		int rc = 0;
1696 
1697 		if (enable_wanted) {
1698 			/* Change of mode requires disable */
1699 			if (efx->ptp_data->enabled &&
1700 			    (efx->ptp_data->mode != new_mode)) {
1701 				efx->ptp_data->enabled = false;
1702 				rc = efx_ptp_stop(efx);
1703 				if (rc != 0)
1704 					return rc;
1705 			}
1706 
1707 			/* Set new operating mode and establish
1708 			 * baseline synchronisation, which must
1709 			 * succeed.
1710 			 */
1711 			efx->ptp_data->mode = new_mode;
1712 			if (netif_running(efx->net_dev))
1713 				rc = efx_ptp_start(efx);
1714 			if (rc == 0) {
1715 				rc = efx_ptp_synchronize(efx,
1716 							 PTP_SYNC_ATTEMPTS * 2);
1717 				if (rc != 0)
1718 					efx_ptp_stop(efx);
1719 			}
1720 		} else {
1721 			rc = efx_ptp_stop(efx);
1722 		}
1723 
1724 		if (rc != 0)
1725 			return rc;
1726 
1727 		efx->ptp_data->enabled = enable_wanted;
1728 	}
1729 
1730 	return 0;
1731 }
1732 
1733 static int efx_ptp_ts_init(struct efx_nic *efx, struct hwtstamp_config *init)
1734 {
1735 	int rc;
1736 
1737 	if (init->flags)
1738 		return -EINVAL;
1739 
1740 	if ((init->tx_type != HWTSTAMP_TX_OFF) &&
1741 	    (init->tx_type != HWTSTAMP_TX_ON))
1742 		return -ERANGE;
1743 
1744 	rc = efx->type->ptp_set_ts_config(efx, init);
1745 	if (rc)
1746 		return rc;
1747 
1748 	efx->ptp_data->config = *init;
1749 	return 0;
1750 }
1751 
1752 void efx_ptp_get_ts_info(struct efx_nic *efx, struct ethtool_ts_info *ts_info)
1753 {
1754 	struct efx_ptp_data *ptp = efx->ptp_data;
1755 	struct efx_nic *primary = efx->primary;
1756 
1757 	ASSERT_RTNL();
1758 
1759 	if (!ptp)
1760 		return;
1761 
1762 	ts_info->so_timestamping |= (SOF_TIMESTAMPING_TX_HARDWARE |
1763 				     SOF_TIMESTAMPING_RX_HARDWARE |
1764 				     SOF_TIMESTAMPING_RAW_HARDWARE);
1765 	/* Check licensed features.  If we don't have the license for TX
1766 	 * timestamps, the NIC will not support them.
1767 	 */
1768 	if (efx_ptp_use_mac_tx_timestamps(efx)) {
1769 		struct efx_ef10_nic_data *nic_data = efx->nic_data;
1770 
1771 		if (!(nic_data->licensed_features &
1772 		      (1 << LICENSED_V3_FEATURES_TX_TIMESTAMPS_LBN)))
1773 			ts_info->so_timestamping &=
1774 				~SOF_TIMESTAMPING_TX_HARDWARE;
1775 	}
1776 	if (primary && primary->ptp_data && primary->ptp_data->phc_clock)
1777 		ts_info->phc_index =
1778 			ptp_clock_index(primary->ptp_data->phc_clock);
1779 	ts_info->tx_types = 1 << HWTSTAMP_TX_OFF | 1 << HWTSTAMP_TX_ON;
1780 	ts_info->rx_filters = ptp->efx->type->hwtstamp_filters;
1781 }
1782 
1783 int efx_ptp_set_ts_config(struct efx_nic *efx, struct ifreq *ifr)
1784 {
1785 	struct hwtstamp_config config;
1786 	int rc;
1787 
1788 	/* Not a PTP enabled port */
1789 	if (!efx->ptp_data)
1790 		return -EOPNOTSUPP;
1791 
1792 	if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
1793 		return -EFAULT;
1794 
1795 	rc = efx_ptp_ts_init(efx, &config);
1796 	if (rc != 0)
1797 		return rc;
1798 
1799 	return copy_to_user(ifr->ifr_data, &config, sizeof(config))
1800 		? -EFAULT : 0;
1801 }
1802 
1803 int efx_ptp_get_ts_config(struct efx_nic *efx, struct ifreq *ifr)
1804 {
1805 	if (!efx->ptp_data)
1806 		return -EOPNOTSUPP;
1807 
1808 	return copy_to_user(ifr->ifr_data, &efx->ptp_data->config,
1809 			    sizeof(efx->ptp_data->config)) ? -EFAULT : 0;
1810 }
1811 
1812 static void ptp_event_failure(struct efx_nic *efx, int expected_frag_len)
1813 {
1814 	struct efx_ptp_data *ptp = efx->ptp_data;
1815 
1816 	netif_err(efx, hw, efx->net_dev,
1817 		"PTP unexpected event length: got %d expected %d\n",
1818 		ptp->evt_frag_idx, expected_frag_len);
1819 	ptp->reset_required = true;
1820 	queue_work(ptp->workwq, &ptp->work);
1821 }
1822 
1823 /* Process a completed receive event.  Put it on the event queue and
1824  * start worker thread.  This is required because event and their
1825  * correspoding packets may come in either order.
1826  */
1827 static void ptp_event_rx(struct efx_nic *efx, struct efx_ptp_data *ptp)
1828 {
1829 	struct efx_ptp_event_rx *evt = NULL;
1830 
1831 	if (WARN_ON_ONCE(ptp->rx_ts_inline))
1832 		return;
1833 
1834 	if (ptp->evt_frag_idx != 3) {
1835 		ptp_event_failure(efx, 3);
1836 		return;
1837 	}
1838 
1839 	spin_lock_bh(&ptp->evt_lock);
1840 	if (!list_empty(&ptp->evt_free_list)) {
1841 		evt = list_first_entry(&ptp->evt_free_list,
1842 				       struct efx_ptp_event_rx, link);
1843 		list_del(&evt->link);
1844 
1845 		evt->seq0 = EFX_QWORD_FIELD(ptp->evt_frags[2], MCDI_EVENT_DATA);
1846 		evt->seq1 = (EFX_QWORD_FIELD(ptp->evt_frags[2],
1847 					     MCDI_EVENT_SRC)        |
1848 			     (EFX_QWORD_FIELD(ptp->evt_frags[1],
1849 					      MCDI_EVENT_SRC) << 8) |
1850 			     (EFX_QWORD_FIELD(ptp->evt_frags[0],
1851 					      MCDI_EVENT_SRC) << 16));
1852 		evt->hwtimestamp = efx->ptp_data->nic_to_kernel_time(
1853 			EFX_QWORD_FIELD(ptp->evt_frags[0], MCDI_EVENT_DATA),
1854 			EFX_QWORD_FIELD(ptp->evt_frags[1], MCDI_EVENT_DATA),
1855 			ptp->ts_corrections.ptp_rx);
1856 		evt->expiry = jiffies + msecs_to_jiffies(PKT_EVENT_LIFETIME_MS);
1857 		list_add_tail(&evt->link, &ptp->evt_list);
1858 
1859 		queue_work(ptp->workwq, &ptp->work);
1860 	} else if (net_ratelimit()) {
1861 		/* Log a rate-limited warning message. */
1862 		netif_err(efx, rx_err, efx->net_dev, "PTP event queue overflow\n");
1863 	}
1864 	spin_unlock_bh(&ptp->evt_lock);
1865 }
1866 
1867 static void ptp_event_fault(struct efx_nic *efx, struct efx_ptp_data *ptp)
1868 {
1869 	int code = EFX_QWORD_FIELD(ptp->evt_frags[0], MCDI_EVENT_DATA);
1870 	if (ptp->evt_frag_idx != 1) {
1871 		ptp_event_failure(efx, 1);
1872 		return;
1873 	}
1874 
1875 	netif_err(efx, hw, efx->net_dev, "PTP error %d\n", code);
1876 }
1877 
1878 static void ptp_event_pps(struct efx_nic *efx, struct efx_ptp_data *ptp)
1879 {
1880 	if (ptp->nic_ts_enabled)
1881 		queue_work(ptp->pps_workwq, &ptp->pps_work);
1882 }
1883 
1884 void efx_ptp_event(struct efx_nic *efx, efx_qword_t *ev)
1885 {
1886 	struct efx_ptp_data *ptp = efx->ptp_data;
1887 	int code = EFX_QWORD_FIELD(*ev, MCDI_EVENT_CODE);
1888 
1889 	if (!ptp) {
1890 		if (!efx->ptp_warned) {
1891 			netif_warn(efx, drv, efx->net_dev,
1892 				   "Received PTP event but PTP not set up\n");
1893 			efx->ptp_warned = true;
1894 		}
1895 		return;
1896 	}
1897 
1898 	if (!ptp->enabled)
1899 		return;
1900 
1901 	if (ptp->evt_frag_idx == 0) {
1902 		ptp->evt_code = code;
1903 	} else if (ptp->evt_code != code) {
1904 		netif_err(efx, hw, efx->net_dev,
1905 			  "PTP out of sequence event %d\n", code);
1906 		ptp->evt_frag_idx = 0;
1907 	}
1908 
1909 	ptp->evt_frags[ptp->evt_frag_idx++] = *ev;
1910 	if (!MCDI_EVENT_FIELD(*ev, CONT)) {
1911 		/* Process resulting event */
1912 		switch (code) {
1913 		case MCDI_EVENT_CODE_PTP_RX:
1914 			ptp_event_rx(efx, ptp);
1915 			break;
1916 		case MCDI_EVENT_CODE_PTP_FAULT:
1917 			ptp_event_fault(efx, ptp);
1918 			break;
1919 		case MCDI_EVENT_CODE_PTP_PPS:
1920 			ptp_event_pps(efx, ptp);
1921 			break;
1922 		default:
1923 			netif_err(efx, hw, efx->net_dev,
1924 				  "PTP unknown event %d\n", code);
1925 			break;
1926 		}
1927 		ptp->evt_frag_idx = 0;
1928 	} else if (MAX_EVENT_FRAGS == ptp->evt_frag_idx) {
1929 		netif_err(efx, hw, efx->net_dev,
1930 			  "PTP too many event fragments\n");
1931 		ptp->evt_frag_idx = 0;
1932 	}
1933 }
1934 
1935 void efx_time_sync_event(struct efx_channel *channel, efx_qword_t *ev)
1936 {
1937 	struct efx_nic *efx = channel->efx;
1938 	struct efx_ptp_data *ptp = efx->ptp_data;
1939 
1940 	/* When extracting the sync timestamp minor value, we should discard
1941 	 * the least significant two bits. These are not required in order
1942 	 * to reconstruct full-range timestamps and they are optionally used
1943 	 * to report status depending on the options supplied when subscribing
1944 	 * for sync events.
1945 	 */
1946 	channel->sync_timestamp_major = MCDI_EVENT_FIELD(*ev, PTP_TIME_MAJOR);
1947 	channel->sync_timestamp_minor =
1948 		(MCDI_EVENT_FIELD(*ev, PTP_TIME_MINOR_MS_8BITS) & 0xFC)
1949 			<< ptp->nic_time.sync_event_minor_shift;
1950 
1951 	/* if sync events have been disabled then we want to silently ignore
1952 	 * this event, so throw away result.
1953 	 */
1954 	(void) cmpxchg(&channel->sync_events_state, SYNC_EVENTS_REQUESTED,
1955 		       SYNC_EVENTS_VALID);
1956 }
1957 
1958 static inline u32 efx_rx_buf_timestamp_minor(struct efx_nic *efx, const u8 *eh)
1959 {
1960 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
1961 	return __le32_to_cpup((const __le32 *)(eh + efx->rx_packet_ts_offset));
1962 #else
1963 	const u8 *data = eh + efx->rx_packet_ts_offset;
1964 	return (u32)data[0]       |
1965 	       (u32)data[1] << 8  |
1966 	       (u32)data[2] << 16 |
1967 	       (u32)data[3] << 24;
1968 #endif
1969 }
1970 
1971 void __efx_rx_skb_attach_timestamp(struct efx_channel *channel,
1972 				   struct sk_buff *skb)
1973 {
1974 	struct efx_nic *efx = channel->efx;
1975 	struct efx_ptp_data *ptp = efx->ptp_data;
1976 	u32 pkt_timestamp_major, pkt_timestamp_minor;
1977 	u32 diff, carry;
1978 	struct skb_shared_hwtstamps *timestamps;
1979 
1980 	if (channel->sync_events_state != SYNC_EVENTS_VALID)
1981 		return;
1982 
1983 	pkt_timestamp_minor = efx_rx_buf_timestamp_minor(efx, skb_mac_header(skb));
1984 
1985 	/* get the difference between the packet and sync timestamps,
1986 	 * modulo one second
1987 	 */
1988 	diff = pkt_timestamp_minor - channel->sync_timestamp_minor;
1989 	if (pkt_timestamp_minor < channel->sync_timestamp_minor)
1990 		diff += ptp->nic_time.minor_max;
1991 
1992 	/* do we roll over a second boundary and need to carry the one? */
1993 	carry = (channel->sync_timestamp_minor >= ptp->nic_time.minor_max - diff) ?
1994 		1 : 0;
1995 
1996 	if (diff <= ptp->nic_time.sync_event_diff_max) {
1997 		/* packet is ahead of the sync event by a quarter of a second or
1998 		 * less (allowing for fuzz)
1999 		 */
2000 		pkt_timestamp_major = channel->sync_timestamp_major + carry;
2001 	} else if (diff >= ptp->nic_time.sync_event_diff_min) {
2002 		/* packet is behind the sync event but within the fuzz factor.
2003 		 * This means the RX packet and sync event crossed as they were
2004 		 * placed on the event queue, which can sometimes happen.
2005 		 */
2006 		pkt_timestamp_major = channel->sync_timestamp_major - 1 + carry;
2007 	} else {
2008 		/* it's outside tolerance in both directions. this might be
2009 		 * indicative of us missing sync events for some reason, so
2010 		 * we'll call it an error rather than risk giving a bogus
2011 		 * timestamp.
2012 		 */
2013 		netif_vdbg(efx, drv, efx->net_dev,
2014 			  "packet timestamp %x too far from sync event %x:%x\n",
2015 			  pkt_timestamp_minor, channel->sync_timestamp_major,
2016 			  channel->sync_timestamp_minor);
2017 		return;
2018 	}
2019 
2020 	/* attach the timestamps to the skb */
2021 	timestamps = skb_hwtstamps(skb);
2022 	timestamps->hwtstamp =
2023 		ptp->nic_to_kernel_time(pkt_timestamp_major,
2024 					pkt_timestamp_minor,
2025 					ptp->ts_corrections.general_rx);
2026 }
2027 
2028 static int efx_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta)
2029 {
2030 	struct efx_ptp_data *ptp_data = container_of(ptp,
2031 						     struct efx_ptp_data,
2032 						     phc_clock_info);
2033 	struct efx_nic *efx = ptp_data->efx;
2034 	MCDI_DECLARE_BUF(inadj, MC_CMD_PTP_IN_ADJUST_LEN);
2035 	s64 adjustment_ns;
2036 	int rc;
2037 
2038 	if (delta > MAX_PPB)
2039 		delta = MAX_PPB;
2040 	else if (delta < -MAX_PPB)
2041 		delta = -MAX_PPB;
2042 
2043 	/* Convert ppb to fixed point ns taking care to round correctly. */
2044 	adjustment_ns = ((s64)delta * PPB_SCALE_WORD +
2045 			 (1 << (ptp_data->adjfreq_ppb_shift - 1))) >>
2046 			ptp_data->adjfreq_ppb_shift;
2047 
2048 	MCDI_SET_DWORD(inadj, PTP_IN_OP, MC_CMD_PTP_OP_ADJUST);
2049 	MCDI_SET_DWORD(inadj, PTP_IN_PERIPH_ID, 0);
2050 	MCDI_SET_QWORD(inadj, PTP_IN_ADJUST_FREQ, adjustment_ns);
2051 	MCDI_SET_DWORD(inadj, PTP_IN_ADJUST_SECONDS, 0);
2052 	MCDI_SET_DWORD(inadj, PTP_IN_ADJUST_NANOSECONDS, 0);
2053 	rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inadj, sizeof(inadj),
2054 			  NULL, 0, NULL);
2055 	if (rc != 0)
2056 		return rc;
2057 
2058 	ptp_data->current_adjfreq = adjustment_ns;
2059 	return 0;
2060 }
2061 
2062 static int efx_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
2063 {
2064 	u32 nic_major, nic_minor;
2065 	struct efx_ptp_data *ptp_data = container_of(ptp,
2066 						     struct efx_ptp_data,
2067 						     phc_clock_info);
2068 	struct efx_nic *efx = ptp_data->efx;
2069 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_ADJUST_LEN);
2070 
2071 	efx->ptp_data->ns_to_nic_time(delta, &nic_major, &nic_minor);
2072 
2073 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_ADJUST);
2074 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
2075 	MCDI_SET_QWORD(inbuf, PTP_IN_ADJUST_FREQ, ptp_data->current_adjfreq);
2076 	MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_MAJOR, nic_major);
2077 	MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_MINOR, nic_minor);
2078 	return efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
2079 			    NULL, 0, NULL);
2080 }
2081 
2082 static int efx_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
2083 {
2084 	struct efx_ptp_data *ptp_data = container_of(ptp,
2085 						     struct efx_ptp_data,
2086 						     phc_clock_info);
2087 	struct efx_nic *efx = ptp_data->efx;
2088 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_READ_NIC_TIME_LEN);
2089 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_READ_NIC_TIME_LEN);
2090 	int rc;
2091 	ktime_t kt;
2092 
2093 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_READ_NIC_TIME);
2094 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
2095 
2096 	rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
2097 			  outbuf, sizeof(outbuf), NULL);
2098 	if (rc != 0)
2099 		return rc;
2100 
2101 	kt = ptp_data->nic_to_kernel_time(
2102 		MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_MAJOR),
2103 		MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_MINOR), 0);
2104 	*ts = ktime_to_timespec64(kt);
2105 	return 0;
2106 }
2107 
2108 static int efx_phc_settime(struct ptp_clock_info *ptp,
2109 			   const struct timespec64 *e_ts)
2110 {
2111 	/* Get the current NIC time, efx_phc_gettime.
2112 	 * Subtract from the desired time to get the offset
2113 	 * call efx_phc_adjtime with the offset
2114 	 */
2115 	int rc;
2116 	struct timespec64 time_now;
2117 	struct timespec64 delta;
2118 
2119 	rc = efx_phc_gettime(ptp, &time_now);
2120 	if (rc != 0)
2121 		return rc;
2122 
2123 	delta = timespec64_sub(*e_ts, time_now);
2124 
2125 	rc = efx_phc_adjtime(ptp, timespec64_to_ns(&delta));
2126 	if (rc != 0)
2127 		return rc;
2128 
2129 	return 0;
2130 }
2131 
2132 static int efx_phc_enable(struct ptp_clock_info *ptp,
2133 			  struct ptp_clock_request *request,
2134 			  int enable)
2135 {
2136 	struct efx_ptp_data *ptp_data = container_of(ptp,
2137 						     struct efx_ptp_data,
2138 						     phc_clock_info);
2139 	if (request->type != PTP_CLK_REQ_PPS)
2140 		return -EOPNOTSUPP;
2141 
2142 	ptp_data->nic_ts_enabled = !!enable;
2143 	return 0;
2144 }
2145 
2146 static const struct efx_channel_type efx_ptp_channel_type = {
2147 	.handle_no_channel	= efx_ptp_handle_no_channel,
2148 	.pre_probe		= efx_ptp_probe_channel,
2149 	.post_remove		= efx_ptp_remove_channel,
2150 	.get_name		= efx_ptp_get_channel_name,
2151 	/* no copy operation; there is no need to reallocate this channel */
2152 	.receive_skb		= efx_ptp_rx,
2153 	.want_txqs		= efx_ptp_want_txqs,
2154 	.keep_eventq		= false,
2155 };
2156 
2157 void efx_ptp_defer_probe_with_channel(struct efx_nic *efx)
2158 {
2159 	/* Check whether PTP is implemented on this NIC.  The DISABLE
2160 	 * operation will succeed if and only if it is implemented.
2161 	 */
2162 	if (efx_ptp_disable(efx) == 0)
2163 		efx->extra_channel_type[EFX_EXTRA_CHANNEL_PTP] =
2164 			&efx_ptp_channel_type;
2165 }
2166 
2167 void efx_ptp_start_datapath(struct efx_nic *efx)
2168 {
2169 	if (efx_ptp_restart(efx))
2170 		netif_err(efx, drv, efx->net_dev, "Failed to restart PTP.\n");
2171 	/* re-enable timestamping if it was previously enabled */
2172 	if (efx->type->ptp_set_ts_sync_events)
2173 		efx->type->ptp_set_ts_sync_events(efx, true, true);
2174 }
2175 
2176 void efx_ptp_stop_datapath(struct efx_nic *efx)
2177 {
2178 	/* temporarily disable timestamping */
2179 	if (efx->type->ptp_set_ts_sync_events)
2180 		efx->type->ptp_set_ts_sync_events(efx, false, true);
2181 	efx_ptp_stop(efx);
2182 }
2183