1/****************************************************************************
2 * Driver for Solarflare network controllers and boards
3 * Copyright 2011-2013 Solarflare Communications Inc.
4 *
5 * This program is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 as published
7 * by the Free Software Foundation, incorporated herein by reference.
8 */
9
10/* Theory of operation:
11 *
12 * PTP support is assisted by firmware running on the MC, which provides
13 * the hardware timestamping capabilities.  Both transmitted and received
14 * PTP event packets are queued onto internal queues for subsequent processing;
15 * this is because the MC operations are relatively long and would block
16 * block NAPI/interrupt operation.
17 *
18 * Receive event processing:
19 *	The event contains the packet's UUID and sequence number, together
20 *	with the hardware timestamp.  The PTP receive packet queue is searched
21 *	for this UUID/sequence number and, if found, put on a pending queue.
22 *	Packets not matching are delivered without timestamps (MCDI events will
23 *	always arrive after the actual packet).
24 *	It is important for the operation of the PTP protocol that the ordering
25 *	of packets between the event and general port is maintained.
26 *
27 * Work queue processing:
28 *	If work waiting, synchronise host/hardware time
29 *
30 *	Transmit: send packet through MC, which returns the transmission time
31 *	that is converted to an appropriate timestamp.
32 *
33 *	Receive: the packet's reception time is converted to an appropriate
34 *	timestamp.
35 */
36#include <linux/ip.h>
37#include <linux/udp.h>
38#include <linux/time.h>
39#include <linux/ktime.h>
40#include <linux/module.h>
41#include <linux/net_tstamp.h>
42#include <linux/pps_kernel.h>
43#include <linux/ptp_clock_kernel.h>
44#include "net_driver.h"
45#include "efx.h"
46#include "mcdi.h"
47#include "mcdi_pcol.h"
48#include "io.h"
49#include "farch_regs.h"
50#include "nic.h"
51
52/* Maximum number of events expected to make up a PTP event */
53#define	MAX_EVENT_FRAGS			3
54
55/* Maximum delay, ms, to begin synchronisation */
56#define	MAX_SYNCHRONISE_WAIT_MS		2
57
58/* How long, at most, to spend synchronising */
59#define	SYNCHRONISE_PERIOD_NS		250000
60
61/* How often to update the shared memory time */
62#define	SYNCHRONISATION_GRANULARITY_NS	200
63
64/* Minimum permitted length of a (corrected) synchronisation time */
65#define	DEFAULT_MIN_SYNCHRONISATION_NS	120
66
67/* Maximum permitted length of a (corrected) synchronisation time */
68#define	MAX_SYNCHRONISATION_NS		1000
69
70/* How many (MC) receive events that can be queued */
71#define	MAX_RECEIVE_EVENTS		8
72
73/* Length of (modified) moving average. */
74#define	AVERAGE_LENGTH			16
75
76/* How long an unmatched event or packet can be held */
77#define PKT_EVENT_LIFETIME_MS		10
78
79/* Offsets into PTP packet for identification.  These offsets are from the
80 * start of the IP header, not the MAC header.  Note that neither PTP V1 nor
81 * PTP V2 permit the use of IPV4 options.
82 */
83#define PTP_DPORT_OFFSET	22
84
85#define PTP_V1_VERSION_LENGTH	2
86#define PTP_V1_VERSION_OFFSET	28
87
88#define PTP_V1_UUID_LENGTH	6
89#define PTP_V1_UUID_OFFSET	50
90
91#define PTP_V1_SEQUENCE_LENGTH	2
92#define PTP_V1_SEQUENCE_OFFSET	58
93
94/* The minimum length of a PTP V1 packet for offsets, etc. to be valid:
95 * includes IP header.
96 */
97#define	PTP_V1_MIN_LENGTH	64
98
99#define PTP_V2_VERSION_LENGTH	1
100#define PTP_V2_VERSION_OFFSET	29
101
102#define PTP_V2_UUID_LENGTH	8
103#define PTP_V2_UUID_OFFSET	48
104
105/* Although PTP V2 UUIDs are comprised a ClockIdentity (8) and PortNumber (2),
106 * the MC only captures the last six bytes of the clock identity. These values
107 * reflect those, not the ones used in the standard.  The standard permits
108 * mapping of V1 UUIDs to V2 UUIDs with these same values.
109 */
110#define PTP_V2_MC_UUID_LENGTH	6
111#define PTP_V2_MC_UUID_OFFSET	50
112
113#define PTP_V2_SEQUENCE_LENGTH	2
114#define PTP_V2_SEQUENCE_OFFSET	58
115
116/* The minimum length of a PTP V2 packet for offsets, etc. to be valid:
117 * includes IP header.
118 */
119#define	PTP_V2_MIN_LENGTH	63
120
121#define	PTP_MIN_LENGTH		63
122
123#define PTP_ADDRESS		0xe0000181	/* 224.0.1.129 */
124#define PTP_EVENT_PORT		319
125#define PTP_GENERAL_PORT	320
126
127/* Annoyingly the format of the version numbers are different between
128 * versions 1 and 2 so it isn't possible to simply look for 1 or 2.
129 */
130#define	PTP_VERSION_V1		1
131
132#define	PTP_VERSION_V2		2
133#define	PTP_VERSION_V2_MASK	0x0f
134
135enum ptp_packet_state {
136	PTP_PACKET_STATE_UNMATCHED = 0,
137	PTP_PACKET_STATE_MATCHED,
138	PTP_PACKET_STATE_TIMED_OUT,
139	PTP_PACKET_STATE_MATCH_UNWANTED
140};
141
142/* NIC synchronised with single word of time only comprising
143 * partial seconds and full nanoseconds: 10^9 ~ 2^30 so 2 bits for seconds.
144 */
145#define	MC_NANOSECOND_BITS	30
146#define	MC_NANOSECOND_MASK	((1 << MC_NANOSECOND_BITS) - 1)
147#define	MC_SECOND_MASK		((1 << (32 - MC_NANOSECOND_BITS)) - 1)
148
149/* Maximum parts-per-billion adjustment that is acceptable */
150#define MAX_PPB			1000000
151
152/* Number of bits required to hold the above */
153#define	MAX_PPB_BITS		20
154
155/* Number of extra bits allowed when calculating fractional ns.
156 * EXTRA_BITS + MC_CMD_PTP_IN_ADJUST_BITS + MAX_PPB_BITS should
157 * be less than 63.
158 */
159#define	PPB_EXTRA_BITS		2
160
161/* Precalculate scale word to avoid long long division at runtime */
162#define	PPB_SCALE_WORD	((1LL << (PPB_EXTRA_BITS + MC_CMD_PTP_IN_ADJUST_BITS +\
163			MAX_PPB_BITS)) / 1000000000LL)
164
165#define PTP_SYNC_ATTEMPTS	4
166
167/**
168 * struct efx_ptp_match - Matching structure, stored in sk_buff's cb area.
169 * @words: UUID and (partial) sequence number
170 * @expiry: Time after which the packet should be delivered irrespective of
171 *            event arrival.
172 * @state: The state of the packet - whether it is ready for processing or
173 *         whether that is of no interest.
174 */
175struct efx_ptp_match {
176	u32 words[DIV_ROUND_UP(PTP_V1_UUID_LENGTH, 4)];
177	unsigned long expiry;
178	enum ptp_packet_state state;
179};
180
181/**
182 * struct efx_ptp_event_rx - A PTP receive event (from MC)
183 * @seq0: First part of (PTP) UUID
184 * @seq1: Second part of (PTP) UUID and sequence number
185 * @hwtimestamp: Event timestamp
186 */
187struct efx_ptp_event_rx {
188	struct list_head link;
189	u32 seq0;
190	u32 seq1;
191	ktime_t hwtimestamp;
192	unsigned long expiry;
193};
194
195/**
196 * struct efx_ptp_timeset - Synchronisation between host and MC
197 * @host_start: Host time immediately before hardware timestamp taken
198 * @major: Hardware timestamp, major
199 * @minor: Hardware timestamp, minor
200 * @host_end: Host time immediately after hardware timestamp taken
201 * @wait: Number of NIC clock ticks between hardware timestamp being read and
202 *          host end time being seen
203 * @window: Difference of host_end and host_start
204 * @valid: Whether this timeset is valid
205 */
206struct efx_ptp_timeset {
207	u32 host_start;
208	u32 major;
209	u32 minor;
210	u32 host_end;
211	u32 wait;
212	u32 window;	/* Derived: end - start, allowing for wrap */
213};
214
215/**
216 * struct efx_ptp_data - Precision Time Protocol (PTP) state
217 * @efx: The NIC context
218 * @channel: The PTP channel (Siena only)
219 * @rx_ts_inline: Flag for whether RX timestamps are inline (else they are
220 *	separate events)
221 * @rxq: Receive queue (awaiting timestamps)
222 * @txq: Transmit queue
223 * @evt_list: List of MC receive events awaiting packets
224 * @evt_free_list: List of free events
225 * @evt_lock: Lock for manipulating evt_list and evt_free_list
226 * @rx_evts: Instantiated events (on evt_list and evt_free_list)
227 * @workwq: Work queue for processing pending PTP operations
228 * @work: Work task
229 * @reset_required: A serious error has occurred and the PTP task needs to be
230 *                  reset (disable, enable).
231 * @rxfilter_event: Receive filter when operating
232 * @rxfilter_general: Receive filter when operating
233 * @config: Current timestamp configuration
234 * @enabled: PTP operation enabled
235 * @mode: Mode in which PTP operating (PTP version)
236 * @time_format: Time format supported by this NIC
237 * @ns_to_nic_time: Function to convert from scalar nanoseconds to NIC time
238 * @nic_to_kernel_time: Function to convert from NIC to kernel time
239 * @min_synchronisation_ns: Minimum acceptable corrected sync window
240 * @ts_corrections.tx: Required driver correction of transmit timestamps
241 * @ts_corrections.rx: Required driver correction of receive timestamps
242 * @ts_corrections.pps_out: PPS output error (information only)
243 * @ts_corrections.pps_in: Required driver correction of PPS input timestamps
244 * @evt_frags: Partly assembled PTP events
245 * @evt_frag_idx: Current fragment number
246 * @evt_code: Last event code
247 * @start: Address at which MC indicates ready for synchronisation
248 * @host_time_pps: Host time at last PPS
249 * @current_adjfreq: Current ppb adjustment.
250 * @phc_clock: Pointer to registered phc device (if primary function)
251 * @phc_clock_info: Registration structure for phc device
252 * @pps_work: pps work task for handling pps events
253 * @pps_workwq: pps work queue
254 * @nic_ts_enabled: Flag indicating if NIC generated TS events are handled
255 * @txbuf: Buffer for use when transmitting (PTP) packets to MC (avoids
256 *         allocations in main data path).
257 * @good_syncs: Number of successful synchronisations.
258 * @fast_syncs: Number of synchronisations requiring short delay
259 * @bad_syncs: Number of failed synchronisations.
260 * @sync_timeouts: Number of synchronisation timeouts
261 * @no_time_syncs: Number of synchronisations with no good times.
262 * @invalid_sync_windows: Number of sync windows with bad durations.
263 * @undersize_sync_windows: Number of corrected sync windows that are too small
264 * @oversize_sync_windows: Number of corrected sync windows that are too large
265 * @rx_no_timestamp: Number of packets received without a timestamp.
266 * @timeset: Last set of synchronisation statistics.
267 */
268struct efx_ptp_data {
269	struct efx_nic *efx;
270	struct efx_channel *channel;
271	bool rx_ts_inline;
272	struct sk_buff_head rxq;
273	struct sk_buff_head txq;
274	struct list_head evt_list;
275	struct list_head evt_free_list;
276	spinlock_t evt_lock;
277	struct efx_ptp_event_rx rx_evts[MAX_RECEIVE_EVENTS];
278	struct workqueue_struct *workwq;
279	struct work_struct work;
280	bool reset_required;
281	u32 rxfilter_event;
282	u32 rxfilter_general;
283	bool rxfilter_installed;
284	struct hwtstamp_config config;
285	bool enabled;
286	unsigned int mode;
287	unsigned int time_format;
288	void (*ns_to_nic_time)(s64 ns, u32 *nic_major, u32 *nic_minor);
289	ktime_t (*nic_to_kernel_time)(u32 nic_major, u32 nic_minor,
290				      s32 correction);
291	unsigned int min_synchronisation_ns;
292	struct {
293		s32 tx;
294		s32 rx;
295		s32 pps_out;
296		s32 pps_in;
297	} ts_corrections;
298	efx_qword_t evt_frags[MAX_EVENT_FRAGS];
299	int evt_frag_idx;
300	int evt_code;
301	struct efx_buffer start;
302	struct pps_event_time host_time_pps;
303	s64 current_adjfreq;
304	struct ptp_clock *phc_clock;
305	struct ptp_clock_info phc_clock_info;
306	struct work_struct pps_work;
307	struct workqueue_struct *pps_workwq;
308	bool nic_ts_enabled;
309	MCDI_DECLARE_BUF(txbuf, MC_CMD_PTP_IN_TRANSMIT_LENMAX);
310
311	unsigned int good_syncs;
312	unsigned int fast_syncs;
313	unsigned int bad_syncs;
314	unsigned int sync_timeouts;
315	unsigned int no_time_syncs;
316	unsigned int invalid_sync_windows;
317	unsigned int undersize_sync_windows;
318	unsigned int oversize_sync_windows;
319	unsigned int rx_no_timestamp;
320	struct efx_ptp_timeset
321	timeset[MC_CMD_PTP_OUT_SYNCHRONIZE_TIMESET_MAXNUM];
322};
323
324static int efx_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta);
325static int efx_phc_adjtime(struct ptp_clock_info *ptp, s64 delta);
326static int efx_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts);
327static int efx_phc_settime(struct ptp_clock_info *ptp,
328			   const struct timespec64 *e_ts);
329static int efx_phc_enable(struct ptp_clock_info *ptp,
330			  struct ptp_clock_request *request, int on);
331
332#define PTP_SW_STAT(ext_name, field_name)				\
333	{ #ext_name, 0, offsetof(struct efx_ptp_data, field_name) }
334#define PTP_MC_STAT(ext_name, mcdi_name)				\
335	{ #ext_name, 32, MC_CMD_PTP_OUT_STATUS_STATS_ ## mcdi_name ## _OFST }
336static const struct efx_hw_stat_desc efx_ptp_stat_desc[] = {
337	PTP_SW_STAT(ptp_good_syncs, good_syncs),
338	PTP_SW_STAT(ptp_fast_syncs, fast_syncs),
339	PTP_SW_STAT(ptp_bad_syncs, bad_syncs),
340	PTP_SW_STAT(ptp_sync_timeouts, sync_timeouts),
341	PTP_SW_STAT(ptp_no_time_syncs, no_time_syncs),
342	PTP_SW_STAT(ptp_invalid_sync_windows, invalid_sync_windows),
343	PTP_SW_STAT(ptp_undersize_sync_windows, undersize_sync_windows),
344	PTP_SW_STAT(ptp_oversize_sync_windows, oversize_sync_windows),
345	PTP_SW_STAT(ptp_rx_no_timestamp, rx_no_timestamp),
346	PTP_MC_STAT(ptp_tx_timestamp_packets, TX),
347	PTP_MC_STAT(ptp_rx_timestamp_packets, RX),
348	PTP_MC_STAT(ptp_timestamp_packets, TS),
349	PTP_MC_STAT(ptp_filter_matches, FM),
350	PTP_MC_STAT(ptp_non_filter_matches, NFM),
351};
352#define PTP_STAT_COUNT ARRAY_SIZE(efx_ptp_stat_desc)
353static const unsigned long efx_ptp_stat_mask[] = {
354	[0 ... BITS_TO_LONGS(PTP_STAT_COUNT) - 1] = ~0UL,
355};
356
357size_t efx_ptp_describe_stats(struct efx_nic *efx, u8 *strings)
358{
359	if (!efx->ptp_data)
360		return 0;
361
362	return efx_nic_describe_stats(efx_ptp_stat_desc, PTP_STAT_COUNT,
363				      efx_ptp_stat_mask, strings);
364}
365
366size_t efx_ptp_update_stats(struct efx_nic *efx, u64 *stats)
367{
368	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_STATUS_LEN);
369	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_STATUS_LEN);
370	size_t i;
371	int rc;
372
373	if (!efx->ptp_data)
374		return 0;
375
376	/* Copy software statistics */
377	for (i = 0; i < PTP_STAT_COUNT; i++) {
378		if (efx_ptp_stat_desc[i].dma_width)
379			continue;
380		stats[i] = *(unsigned int *)((char *)efx->ptp_data +
381					     efx_ptp_stat_desc[i].offset);
382	}
383
384	/* Fetch MC statistics.  We *must* fill in all statistics or
385	 * risk leaking kernel memory to userland, so if the MCDI
386	 * request fails we pretend we got zeroes.
387	 */
388	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_STATUS);
389	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
390	rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
391			  outbuf, sizeof(outbuf), NULL);
392	if (rc) {
393		netif_err(efx, hw, efx->net_dev,
394			  "MC_CMD_PTP_OP_STATUS failed (%d)\n", rc);
395		memset(outbuf, 0, sizeof(outbuf));
396	}
397	efx_nic_update_stats(efx_ptp_stat_desc, PTP_STAT_COUNT,
398			     efx_ptp_stat_mask,
399			     stats, _MCDI_PTR(outbuf, 0), false);
400
401	return PTP_STAT_COUNT;
402}
403
404/* For Siena platforms NIC time is s and ns */
405static void efx_ptp_ns_to_s_ns(s64 ns, u32 *nic_major, u32 *nic_minor)
406{
407	struct timespec ts = ns_to_timespec(ns);
408	*nic_major = ts.tv_sec;
409	*nic_minor = ts.tv_nsec;
410}
411
412static ktime_t efx_ptp_s_ns_to_ktime_correction(u32 nic_major, u32 nic_minor,
413						s32 correction)
414{
415	ktime_t kt = ktime_set(nic_major, nic_minor);
416	if (correction >= 0)
417		kt = ktime_add_ns(kt, (u64)correction);
418	else
419		kt = ktime_sub_ns(kt, (u64)-correction);
420	return kt;
421}
422
423/* To convert from s27 format to ns we multiply then divide by a power of 2.
424 * For the conversion from ns to s27, the operation is also converted to a
425 * multiply and shift.
426 */
427#define S27_TO_NS_SHIFT	(27)
428#define NS_TO_S27_MULT	(((1ULL << 63) + NSEC_PER_SEC / 2) / NSEC_PER_SEC)
429#define NS_TO_S27_SHIFT	(63 - S27_TO_NS_SHIFT)
430#define S27_MINOR_MAX	(1 << S27_TO_NS_SHIFT)
431
432/* For Huntington platforms NIC time is in seconds and fractions of a second
433 * where the minor register only uses 27 bits in units of 2^-27s.
434 */
435static void efx_ptp_ns_to_s27(s64 ns, u32 *nic_major, u32 *nic_minor)
436{
437	struct timespec ts = ns_to_timespec(ns);
438	u32 maj = ts.tv_sec;
439	u32 min = (u32)(((u64)ts.tv_nsec * NS_TO_S27_MULT +
440			 (1ULL << (NS_TO_S27_SHIFT - 1))) >> NS_TO_S27_SHIFT);
441
442	/* The conversion can result in the minor value exceeding the maximum.
443	 * In this case, round up to the next second.
444	 */
445	if (min >= S27_MINOR_MAX) {
446		min -= S27_MINOR_MAX;
447		maj++;
448	}
449
450	*nic_major = maj;
451	*nic_minor = min;
452}
453
454static inline ktime_t efx_ptp_s27_to_ktime(u32 nic_major, u32 nic_minor)
455{
456	u32 ns = (u32)(((u64)nic_minor * NSEC_PER_SEC +
457			(1ULL << (S27_TO_NS_SHIFT - 1))) >> S27_TO_NS_SHIFT);
458	return ktime_set(nic_major, ns);
459}
460
461static ktime_t efx_ptp_s27_to_ktime_correction(u32 nic_major, u32 nic_minor,
462					       s32 correction)
463{
464	/* Apply the correction and deal with carry */
465	nic_minor += correction;
466	if ((s32)nic_minor < 0) {
467		nic_minor += S27_MINOR_MAX;
468		nic_major--;
469	} else if (nic_minor >= S27_MINOR_MAX) {
470		nic_minor -= S27_MINOR_MAX;
471		nic_major++;
472	}
473
474	return efx_ptp_s27_to_ktime(nic_major, nic_minor);
475}
476
477/* Get PTP attributes and set up time conversions */
478static int efx_ptp_get_attributes(struct efx_nic *efx)
479{
480	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_GET_ATTRIBUTES_LEN);
481	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_GET_ATTRIBUTES_LEN);
482	struct efx_ptp_data *ptp = efx->ptp_data;
483	int rc;
484	u32 fmt;
485	size_t out_len;
486
487	/* Get the PTP attributes. If the NIC doesn't support the operation we
488	 * use the default format for compatibility with older NICs i.e.
489	 * seconds and nanoseconds.
490	 */
491	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_GET_ATTRIBUTES);
492	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
493	rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
494			  outbuf, sizeof(outbuf), &out_len);
495	if (rc == 0)
496		fmt = MCDI_DWORD(outbuf, PTP_OUT_GET_ATTRIBUTES_TIME_FORMAT);
497	else if (rc == -EINVAL)
498		fmt = MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_NANOSECONDS;
499	else
500		return rc;
501
502	if (fmt == MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_27FRACTION) {
503		ptp->ns_to_nic_time = efx_ptp_ns_to_s27;
504		ptp->nic_to_kernel_time = efx_ptp_s27_to_ktime_correction;
505	} else if (fmt == MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_NANOSECONDS) {
506		ptp->ns_to_nic_time = efx_ptp_ns_to_s_ns;
507		ptp->nic_to_kernel_time = efx_ptp_s_ns_to_ktime_correction;
508	} else {
509		return -ERANGE;
510	}
511
512	ptp->time_format = fmt;
513
514	/* MC_CMD_PTP_OP_GET_ATTRIBUTES is an extended version of an older
515	 * operation MC_CMD_PTP_OP_GET_TIME_FORMAT that also returns a value
516	 * to use for the minimum acceptable corrected synchronization window.
517	 * If we have the extra information store it. For older firmware that
518	 * does not implement the extended command use the default value.
519	 */
520	if (rc == 0 && out_len >= MC_CMD_PTP_OUT_GET_ATTRIBUTES_LEN)
521		ptp->min_synchronisation_ns =
522			MCDI_DWORD(outbuf,
523				   PTP_OUT_GET_ATTRIBUTES_SYNC_WINDOW_MIN);
524	else
525		ptp->min_synchronisation_ns = DEFAULT_MIN_SYNCHRONISATION_NS;
526
527	return 0;
528}
529
530/* Get PTP timestamp corrections */
531static int efx_ptp_get_timestamp_corrections(struct efx_nic *efx)
532{
533	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_GET_TIMESTAMP_CORRECTIONS_LEN);
534	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_GET_TIMESTAMP_CORRECTIONS_LEN);
535	int rc;
536
537	/* Get the timestamp corrections from the NIC. If this operation is
538	 * not supported (older NICs) then no correction is required.
539	 */
540	MCDI_SET_DWORD(inbuf, PTP_IN_OP,
541		       MC_CMD_PTP_OP_GET_TIMESTAMP_CORRECTIONS);
542	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
543
544	rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
545			  outbuf, sizeof(outbuf), NULL);
546	if (rc == 0) {
547		efx->ptp_data->ts_corrections.tx = MCDI_DWORD(outbuf,
548			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_TRANSMIT);
549		efx->ptp_data->ts_corrections.rx = MCDI_DWORD(outbuf,
550			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_RECEIVE);
551		efx->ptp_data->ts_corrections.pps_out = MCDI_DWORD(outbuf,
552			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_PPS_OUT);
553		efx->ptp_data->ts_corrections.pps_in = MCDI_DWORD(outbuf,
554			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_PPS_IN);
555	} else if (rc == -EINVAL) {
556		efx->ptp_data->ts_corrections.tx = 0;
557		efx->ptp_data->ts_corrections.rx = 0;
558		efx->ptp_data->ts_corrections.pps_out = 0;
559		efx->ptp_data->ts_corrections.pps_in = 0;
560	} else {
561		return rc;
562	}
563
564	return 0;
565}
566
567/* Enable MCDI PTP support. */
568static int efx_ptp_enable(struct efx_nic *efx)
569{
570	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_ENABLE_LEN);
571	MCDI_DECLARE_BUF_OUT_OR_ERR(outbuf, 0);
572	int rc;
573
574	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_ENABLE);
575	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
576	MCDI_SET_DWORD(inbuf, PTP_IN_ENABLE_QUEUE,
577		       efx->ptp_data->channel ?
578		       efx->ptp_data->channel->channel : 0);
579	MCDI_SET_DWORD(inbuf, PTP_IN_ENABLE_MODE, efx->ptp_data->mode);
580
581	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
582				outbuf, sizeof(outbuf), NULL);
583	rc = (rc == -EALREADY) ? 0 : rc;
584	if (rc)
585		efx_mcdi_display_error(efx, MC_CMD_PTP,
586				       MC_CMD_PTP_IN_ENABLE_LEN,
587				       outbuf, sizeof(outbuf), rc);
588	return rc;
589}
590
591/* Disable MCDI PTP support.
592 *
593 * Note that this function should never rely on the presence of ptp_data -
594 * may be called before that exists.
595 */
596static int efx_ptp_disable(struct efx_nic *efx)
597{
598	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_DISABLE_LEN);
599	MCDI_DECLARE_BUF_OUT_OR_ERR(outbuf, 0);
600	int rc;
601
602	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_DISABLE);
603	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
604	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
605				outbuf, sizeof(outbuf), NULL);
606	rc = (rc == -EALREADY) ? 0 : rc;
607	if (rc)
608		efx_mcdi_display_error(efx, MC_CMD_PTP,
609				       MC_CMD_PTP_IN_DISABLE_LEN,
610				       outbuf, sizeof(outbuf), rc);
611	return rc;
612}
613
614static void efx_ptp_deliver_rx_queue(struct sk_buff_head *q)
615{
616	struct sk_buff *skb;
617
618	while ((skb = skb_dequeue(q))) {
619		local_bh_disable();
620		netif_receive_skb(skb);
621		local_bh_enable();
622	}
623}
624
625static void efx_ptp_handle_no_channel(struct efx_nic *efx)
626{
627	netif_err(efx, drv, efx->net_dev,
628		  "ERROR: PTP requires MSI-X and 1 additional interrupt"
629		  "vector. PTP disabled\n");
630}
631
632/* Repeatedly send the host time to the MC which will capture the hardware
633 * time.
634 */
635static void efx_ptp_send_times(struct efx_nic *efx,
636			       struct pps_event_time *last_time)
637{
638	struct pps_event_time now;
639	struct timespec limit;
640	struct efx_ptp_data *ptp = efx->ptp_data;
641	struct timespec start;
642	int *mc_running = ptp->start.addr;
643
644	pps_get_ts(&now);
645	start = now.ts_real;
646	limit = now.ts_real;
647	timespec_add_ns(&limit, SYNCHRONISE_PERIOD_NS);
648
649	/* Write host time for specified period or until MC is done */
650	while ((timespec_compare(&now.ts_real, &limit) < 0) &&
651	       ACCESS_ONCE(*mc_running)) {
652		struct timespec update_time;
653		unsigned int host_time;
654
655		/* Don't update continuously to avoid saturating the PCIe bus */
656		update_time = now.ts_real;
657		timespec_add_ns(&update_time, SYNCHRONISATION_GRANULARITY_NS);
658		do {
659			pps_get_ts(&now);
660		} while ((timespec_compare(&now.ts_real, &update_time) < 0) &&
661			 ACCESS_ONCE(*mc_running));
662
663		/* Synchronise NIC with single word of time only */
664		host_time = (now.ts_real.tv_sec << MC_NANOSECOND_BITS |
665			     now.ts_real.tv_nsec);
666		/* Update host time in NIC memory */
667		efx->type->ptp_write_host_time(efx, host_time);
668	}
669	*last_time = now;
670}
671
672/* Read a timeset from the MC's results and partial process. */
673static void efx_ptp_read_timeset(MCDI_DECLARE_STRUCT_PTR(data),
674				 struct efx_ptp_timeset *timeset)
675{
676	unsigned start_ns, end_ns;
677
678	timeset->host_start = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTSTART);
679	timeset->major = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_MAJOR);
680	timeset->minor = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_MINOR);
681	timeset->host_end = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTEND),
682	timeset->wait = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_WAITNS);
683
684	/* Ignore seconds */
685	start_ns = timeset->host_start & MC_NANOSECOND_MASK;
686	end_ns = timeset->host_end & MC_NANOSECOND_MASK;
687	/* Allow for rollover */
688	if (end_ns < start_ns)
689		end_ns += NSEC_PER_SEC;
690	/* Determine duration of operation */
691	timeset->window = end_ns - start_ns;
692}
693
694/* Process times received from MC.
695 *
696 * Extract times from returned results, and establish the minimum value
697 * seen.  The minimum value represents the "best" possible time and events
698 * too much greater than this are rejected - the machine is, perhaps, too
699 * busy. A number of readings are taken so that, hopefully, at least one good
700 * synchronisation will be seen in the results.
701 */
702static int
703efx_ptp_process_times(struct efx_nic *efx, MCDI_DECLARE_STRUCT_PTR(synch_buf),
704		      size_t response_length,
705		      const struct pps_event_time *last_time)
706{
707	unsigned number_readings =
708		MCDI_VAR_ARRAY_LEN(response_length,
709				   PTP_OUT_SYNCHRONIZE_TIMESET);
710	unsigned i;
711	unsigned ngood = 0;
712	unsigned last_good = 0;
713	struct efx_ptp_data *ptp = efx->ptp_data;
714	u32 last_sec;
715	u32 start_sec;
716	struct timespec delta;
717	ktime_t mc_time;
718
719	if (number_readings == 0)
720		return -EAGAIN;
721
722	/* Read the set of results and find the last good host-MC
723	 * synchronization result. The MC times when it finishes reading the
724	 * host time so the corrected window time should be fairly constant
725	 * for a given platform. Increment stats for any results that appear
726	 * to be erroneous.
727	 */
728	for (i = 0; i < number_readings; i++) {
729		s32 window, corrected;
730		struct timespec wait;
731
732		efx_ptp_read_timeset(
733			MCDI_ARRAY_STRUCT_PTR(synch_buf,
734					      PTP_OUT_SYNCHRONIZE_TIMESET, i),
735			&ptp->timeset[i]);
736
737		wait = ktime_to_timespec(
738			ptp->nic_to_kernel_time(0, ptp->timeset[i].wait, 0));
739		window = ptp->timeset[i].window;
740		corrected = window - wait.tv_nsec;
741
742		/* We expect the uncorrected synchronization window to be at
743		 * least as large as the interval between host start and end
744		 * times. If it is smaller than this then this is mostly likely
745		 * to be a consequence of the host's time being adjusted.
746		 * Check that the corrected sync window is in a reasonable
747		 * range. If it is out of range it is likely to be because an
748		 * interrupt or other delay occurred between reading the system
749		 * time and writing it to MC memory.
750		 */
751		if (window < SYNCHRONISATION_GRANULARITY_NS) {
752			++ptp->invalid_sync_windows;
753		} else if (corrected >= MAX_SYNCHRONISATION_NS) {
754			++ptp->oversize_sync_windows;
755		} else if (corrected < ptp->min_synchronisation_ns) {
756			++ptp->undersize_sync_windows;
757		} else {
758			ngood++;
759			last_good = i;
760		}
761	}
762
763	if (ngood == 0) {
764		netif_warn(efx, drv, efx->net_dev,
765			   "PTP no suitable synchronisations\n");
766		return -EAGAIN;
767	}
768
769	/* Calculate delay from last good sync (host time) to last_time.
770	 * It is possible that the seconds rolled over between taking
771	 * the start reading and the last value written by the host.  The
772	 * timescales are such that a gap of more than one second is never
773	 * expected.  delta is *not* normalised.
774	 */
775	start_sec = ptp->timeset[last_good].host_start >> MC_NANOSECOND_BITS;
776	last_sec = last_time->ts_real.tv_sec & MC_SECOND_MASK;
777	if (start_sec != last_sec &&
778	    ((start_sec + 1) & MC_SECOND_MASK) != last_sec) {
779		netif_warn(efx, hw, efx->net_dev,
780			   "PTP bad synchronisation seconds\n");
781		return -EAGAIN;
782	}
783	delta.tv_sec = (last_sec - start_sec) & 1;
784	delta.tv_nsec =
785		last_time->ts_real.tv_nsec -
786		(ptp->timeset[last_good].host_start & MC_NANOSECOND_MASK);
787
788	/* Convert the NIC time at last good sync into kernel time.
789	 * No correction is required - this time is the output of a
790	 * firmware process.
791	 */
792	mc_time = ptp->nic_to_kernel_time(ptp->timeset[last_good].major,
793					  ptp->timeset[last_good].minor, 0);
794
795	/* Calculate delay from NIC top of second to last_time */
796	delta.tv_nsec += ktime_to_timespec(mc_time).tv_nsec;
797
798	/* Set PPS timestamp to match NIC top of second */
799	ptp->host_time_pps = *last_time;
800	pps_sub_ts(&ptp->host_time_pps, delta);
801
802	return 0;
803}
804
805/* Synchronize times between the host and the MC */
806static int efx_ptp_synchronize(struct efx_nic *efx, unsigned int num_readings)
807{
808	struct efx_ptp_data *ptp = efx->ptp_data;
809	MCDI_DECLARE_BUF(synch_buf, MC_CMD_PTP_OUT_SYNCHRONIZE_LENMAX);
810	size_t response_length;
811	int rc;
812	unsigned long timeout;
813	struct pps_event_time last_time = {};
814	unsigned int loops = 0;
815	int *start = ptp->start.addr;
816
817	MCDI_SET_DWORD(synch_buf, PTP_IN_OP, MC_CMD_PTP_OP_SYNCHRONIZE);
818	MCDI_SET_DWORD(synch_buf, PTP_IN_PERIPH_ID, 0);
819	MCDI_SET_DWORD(synch_buf, PTP_IN_SYNCHRONIZE_NUMTIMESETS,
820		       num_readings);
821	MCDI_SET_QWORD(synch_buf, PTP_IN_SYNCHRONIZE_START_ADDR,
822		       ptp->start.dma_addr);
823
824	/* Clear flag that signals MC ready */
825	ACCESS_ONCE(*start) = 0;
826	rc = efx_mcdi_rpc_start(efx, MC_CMD_PTP, synch_buf,
827				MC_CMD_PTP_IN_SYNCHRONIZE_LEN);
828	EFX_BUG_ON_PARANOID(rc);
829
830	/* Wait for start from MCDI (or timeout) */
831	timeout = jiffies + msecs_to_jiffies(MAX_SYNCHRONISE_WAIT_MS);
832	while (!ACCESS_ONCE(*start) && (time_before(jiffies, timeout))) {
833		udelay(20);	/* Usually start MCDI execution quickly */
834		loops++;
835	}
836
837	if (loops <= 1)
838		++ptp->fast_syncs;
839	if (!time_before(jiffies, timeout))
840		++ptp->sync_timeouts;
841
842	if (ACCESS_ONCE(*start))
843		efx_ptp_send_times(efx, &last_time);
844
845	/* Collect results */
846	rc = efx_mcdi_rpc_finish(efx, MC_CMD_PTP,
847				 MC_CMD_PTP_IN_SYNCHRONIZE_LEN,
848				 synch_buf, sizeof(synch_buf),
849				 &response_length);
850	if (rc == 0) {
851		rc = efx_ptp_process_times(efx, synch_buf, response_length,
852					   &last_time);
853		if (rc == 0)
854			++ptp->good_syncs;
855		else
856			++ptp->no_time_syncs;
857	}
858
859	/* Increment the bad syncs counter if the synchronize fails, whatever
860	 * the reason.
861	 */
862	if (rc != 0)
863		++ptp->bad_syncs;
864
865	return rc;
866}
867
868/* Transmit a PTP packet, via the MCDI interface, to the wire. */
869static int efx_ptp_xmit_skb(struct efx_nic *efx, struct sk_buff *skb)
870{
871	struct efx_ptp_data *ptp_data = efx->ptp_data;
872	struct skb_shared_hwtstamps timestamps;
873	int rc = -EIO;
874	MCDI_DECLARE_BUF(txtime, MC_CMD_PTP_OUT_TRANSMIT_LEN);
875	size_t len;
876
877	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_OP, MC_CMD_PTP_OP_TRANSMIT);
878	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_PERIPH_ID, 0);
879	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_TRANSMIT_LENGTH, skb->len);
880	if (skb_shinfo(skb)->nr_frags != 0) {
881		rc = skb_linearize(skb);
882		if (rc != 0)
883			goto fail;
884	}
885
886	if (skb->ip_summed == CHECKSUM_PARTIAL) {
887		rc = skb_checksum_help(skb);
888		if (rc != 0)
889			goto fail;
890	}
891	skb_copy_from_linear_data(skb,
892				  MCDI_PTR(ptp_data->txbuf,
893					   PTP_IN_TRANSMIT_PACKET),
894				  skb->len);
895	rc = efx_mcdi_rpc(efx, MC_CMD_PTP,
896			  ptp_data->txbuf, MC_CMD_PTP_IN_TRANSMIT_LEN(skb->len),
897			  txtime, sizeof(txtime), &len);
898	if (rc != 0)
899		goto fail;
900
901	memset(&timestamps, 0, sizeof(timestamps));
902	timestamps.hwtstamp = ptp_data->nic_to_kernel_time(
903		MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_MAJOR),
904		MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_MINOR),
905		ptp_data->ts_corrections.tx);
906
907	skb_tstamp_tx(skb, &timestamps);
908
909	rc = 0;
910
911fail:
912	dev_kfree_skb(skb);
913
914	return rc;
915}
916
917static void efx_ptp_drop_time_expired_events(struct efx_nic *efx)
918{
919	struct efx_ptp_data *ptp = efx->ptp_data;
920	struct list_head *cursor;
921	struct list_head *next;
922
923	if (ptp->rx_ts_inline)
924		return;
925
926	/* Drop time-expired events */
927	spin_lock_bh(&ptp->evt_lock);
928	if (!list_empty(&ptp->evt_list)) {
929		list_for_each_safe(cursor, next, &ptp->evt_list) {
930			struct efx_ptp_event_rx *evt;
931
932			evt = list_entry(cursor, struct efx_ptp_event_rx,
933					 link);
934			if (time_after(jiffies, evt->expiry)) {
935				list_move(&evt->link, &ptp->evt_free_list);
936				netif_warn(efx, hw, efx->net_dev,
937					   "PTP rx event dropped\n");
938			}
939		}
940	}
941	spin_unlock_bh(&ptp->evt_lock);
942}
943
944static enum ptp_packet_state efx_ptp_match_rx(struct efx_nic *efx,
945					      struct sk_buff *skb)
946{
947	struct efx_ptp_data *ptp = efx->ptp_data;
948	bool evts_waiting;
949	struct list_head *cursor;
950	struct list_head *next;
951	struct efx_ptp_match *match;
952	enum ptp_packet_state rc = PTP_PACKET_STATE_UNMATCHED;
953
954	WARN_ON_ONCE(ptp->rx_ts_inline);
955
956	spin_lock_bh(&ptp->evt_lock);
957	evts_waiting = !list_empty(&ptp->evt_list);
958	spin_unlock_bh(&ptp->evt_lock);
959
960	if (!evts_waiting)
961		return PTP_PACKET_STATE_UNMATCHED;
962
963	match = (struct efx_ptp_match *)skb->cb;
964	/* Look for a matching timestamp in the event queue */
965	spin_lock_bh(&ptp->evt_lock);
966	list_for_each_safe(cursor, next, &ptp->evt_list) {
967		struct efx_ptp_event_rx *evt;
968
969		evt = list_entry(cursor, struct efx_ptp_event_rx, link);
970		if ((evt->seq0 == match->words[0]) &&
971		    (evt->seq1 == match->words[1])) {
972			struct skb_shared_hwtstamps *timestamps;
973
974			/* Match - add in hardware timestamp */
975			timestamps = skb_hwtstamps(skb);
976			timestamps->hwtstamp = evt->hwtimestamp;
977
978			match->state = PTP_PACKET_STATE_MATCHED;
979			rc = PTP_PACKET_STATE_MATCHED;
980			list_move(&evt->link, &ptp->evt_free_list);
981			break;
982		}
983	}
984	spin_unlock_bh(&ptp->evt_lock);
985
986	return rc;
987}
988
989/* Process any queued receive events and corresponding packets
990 *
991 * q is returned with all the packets that are ready for delivery.
992 */
993static void efx_ptp_process_events(struct efx_nic *efx, struct sk_buff_head *q)
994{
995	struct efx_ptp_data *ptp = efx->ptp_data;
996	struct sk_buff *skb;
997
998	while ((skb = skb_dequeue(&ptp->rxq))) {
999		struct efx_ptp_match *match;
1000
1001		match = (struct efx_ptp_match *)skb->cb;
1002		if (match->state == PTP_PACKET_STATE_MATCH_UNWANTED) {
1003			__skb_queue_tail(q, skb);
1004		} else if (efx_ptp_match_rx(efx, skb) ==
1005			   PTP_PACKET_STATE_MATCHED) {
1006			__skb_queue_tail(q, skb);
1007		} else if (time_after(jiffies, match->expiry)) {
1008			match->state = PTP_PACKET_STATE_TIMED_OUT;
1009			++ptp->rx_no_timestamp;
1010			__skb_queue_tail(q, skb);
1011		} else {
1012			/* Replace unprocessed entry and stop */
1013			skb_queue_head(&ptp->rxq, skb);
1014			break;
1015		}
1016	}
1017}
1018
1019/* Complete processing of a received packet */
1020static inline void efx_ptp_process_rx(struct efx_nic *efx, struct sk_buff *skb)
1021{
1022	local_bh_disable();
1023	netif_receive_skb(skb);
1024	local_bh_enable();
1025}
1026
1027static void efx_ptp_remove_multicast_filters(struct efx_nic *efx)
1028{
1029	struct efx_ptp_data *ptp = efx->ptp_data;
1030
1031	if (ptp->rxfilter_installed) {
1032		efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED,
1033					  ptp->rxfilter_general);
1034		efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED,
1035					  ptp->rxfilter_event);
1036		ptp->rxfilter_installed = false;
1037	}
1038}
1039
1040static int efx_ptp_insert_multicast_filters(struct efx_nic *efx)
1041{
1042	struct efx_ptp_data *ptp = efx->ptp_data;
1043	struct efx_filter_spec rxfilter;
1044	int rc;
1045
1046	if (!ptp->channel || ptp->rxfilter_installed)
1047		return 0;
1048
1049	/* Must filter on both event and general ports to ensure
1050	 * that there is no packet re-ordering.
1051	 */
1052	efx_filter_init_rx(&rxfilter, EFX_FILTER_PRI_REQUIRED, 0,
1053			   efx_rx_queue_index(
1054				   efx_channel_get_rx_queue(ptp->channel)));
1055	rc = efx_filter_set_ipv4_local(&rxfilter, IPPROTO_UDP,
1056				       htonl(PTP_ADDRESS),
1057				       htons(PTP_EVENT_PORT));
1058	if (rc != 0)
1059		return rc;
1060
1061	rc = efx_filter_insert_filter(efx, &rxfilter, true);
1062	if (rc < 0)
1063		return rc;
1064	ptp->rxfilter_event = rc;
1065
1066	efx_filter_init_rx(&rxfilter, EFX_FILTER_PRI_REQUIRED, 0,
1067			   efx_rx_queue_index(
1068				   efx_channel_get_rx_queue(ptp->channel)));
1069	rc = efx_filter_set_ipv4_local(&rxfilter, IPPROTO_UDP,
1070				       htonl(PTP_ADDRESS),
1071				       htons(PTP_GENERAL_PORT));
1072	if (rc != 0)
1073		goto fail;
1074
1075	rc = efx_filter_insert_filter(efx, &rxfilter, true);
1076	if (rc < 0)
1077		goto fail;
1078	ptp->rxfilter_general = rc;
1079
1080	ptp->rxfilter_installed = true;
1081	return 0;
1082
1083fail:
1084	efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED,
1085				  ptp->rxfilter_event);
1086	return rc;
1087}
1088
1089static int efx_ptp_start(struct efx_nic *efx)
1090{
1091	struct efx_ptp_data *ptp = efx->ptp_data;
1092	int rc;
1093
1094	ptp->reset_required = false;
1095
1096	rc = efx_ptp_insert_multicast_filters(efx);
1097	if (rc)
1098		return rc;
1099
1100	rc = efx_ptp_enable(efx);
1101	if (rc != 0)
1102		goto fail;
1103
1104	ptp->evt_frag_idx = 0;
1105	ptp->current_adjfreq = 0;
1106
1107	return 0;
1108
1109fail:
1110	efx_ptp_remove_multicast_filters(efx);
1111	return rc;
1112}
1113
1114static int efx_ptp_stop(struct efx_nic *efx)
1115{
1116	struct efx_ptp_data *ptp = efx->ptp_data;
1117	struct list_head *cursor;
1118	struct list_head *next;
1119	int rc;
1120
1121	if (ptp == NULL)
1122		return 0;
1123
1124	rc = efx_ptp_disable(efx);
1125
1126	efx_ptp_remove_multicast_filters(efx);
1127
1128	/* Make sure RX packets are really delivered */
1129	efx_ptp_deliver_rx_queue(&efx->ptp_data->rxq);
1130	skb_queue_purge(&efx->ptp_data->txq);
1131
1132	/* Drop any pending receive events */
1133	spin_lock_bh(&efx->ptp_data->evt_lock);
1134	list_for_each_safe(cursor, next, &efx->ptp_data->evt_list) {
1135		list_move(cursor, &efx->ptp_data->evt_free_list);
1136	}
1137	spin_unlock_bh(&efx->ptp_data->evt_lock);
1138
1139	return rc;
1140}
1141
1142static int efx_ptp_restart(struct efx_nic *efx)
1143{
1144	if (efx->ptp_data && efx->ptp_data->enabled)
1145		return efx_ptp_start(efx);
1146	return 0;
1147}
1148
1149static void efx_ptp_pps_worker(struct work_struct *work)
1150{
1151	struct efx_ptp_data *ptp =
1152		container_of(work, struct efx_ptp_data, pps_work);
1153	struct efx_nic *efx = ptp->efx;
1154	struct ptp_clock_event ptp_evt;
1155
1156	if (efx_ptp_synchronize(efx, PTP_SYNC_ATTEMPTS))
1157		return;
1158
1159	ptp_evt.type = PTP_CLOCK_PPSUSR;
1160	ptp_evt.pps_times = ptp->host_time_pps;
1161	ptp_clock_event(ptp->phc_clock, &ptp_evt);
1162}
1163
1164static void efx_ptp_worker(struct work_struct *work)
1165{
1166	struct efx_ptp_data *ptp_data =
1167		container_of(work, struct efx_ptp_data, work);
1168	struct efx_nic *efx = ptp_data->efx;
1169	struct sk_buff *skb;
1170	struct sk_buff_head tempq;
1171
1172	if (ptp_data->reset_required) {
1173		efx_ptp_stop(efx);
1174		efx_ptp_start(efx);
1175		return;
1176	}
1177
1178	efx_ptp_drop_time_expired_events(efx);
1179
1180	__skb_queue_head_init(&tempq);
1181	efx_ptp_process_events(efx, &tempq);
1182
1183	while ((skb = skb_dequeue(&ptp_data->txq)))
1184		efx_ptp_xmit_skb(efx, skb);
1185
1186	while ((skb = __skb_dequeue(&tempq)))
1187		efx_ptp_process_rx(efx, skb);
1188}
1189
1190static const struct ptp_clock_info efx_phc_clock_info = {
1191	.owner		= THIS_MODULE,
1192	.name		= "sfc",
1193	.max_adj	= MAX_PPB,
1194	.n_alarm	= 0,
1195	.n_ext_ts	= 0,
1196	.n_per_out	= 0,
1197	.n_pins		= 0,
1198	.pps		= 1,
1199	.adjfreq	= efx_phc_adjfreq,
1200	.adjtime	= efx_phc_adjtime,
1201	.gettime64	= efx_phc_gettime,
1202	.settime64	= efx_phc_settime,
1203	.enable		= efx_phc_enable,
1204};
1205
1206/* Initialise PTP state. */
1207int efx_ptp_probe(struct efx_nic *efx, struct efx_channel *channel)
1208{
1209	struct efx_ptp_data *ptp;
1210	int rc = 0;
1211	unsigned int pos;
1212
1213	ptp = kzalloc(sizeof(struct efx_ptp_data), GFP_KERNEL);
1214	efx->ptp_data = ptp;
1215	if (!efx->ptp_data)
1216		return -ENOMEM;
1217
1218	ptp->efx = efx;
1219	ptp->channel = channel;
1220	ptp->rx_ts_inline = efx_nic_rev(efx) >= EFX_REV_HUNT_A0;
1221
1222	rc = efx_nic_alloc_buffer(efx, &ptp->start, sizeof(int), GFP_KERNEL);
1223	if (rc != 0)
1224		goto fail1;
1225
1226	skb_queue_head_init(&ptp->rxq);
1227	skb_queue_head_init(&ptp->txq);
1228	ptp->workwq = create_singlethread_workqueue("sfc_ptp");
1229	if (!ptp->workwq) {
1230		rc = -ENOMEM;
1231		goto fail2;
1232	}
1233
1234	INIT_WORK(&ptp->work, efx_ptp_worker);
1235	ptp->config.flags = 0;
1236	ptp->config.tx_type = HWTSTAMP_TX_OFF;
1237	ptp->config.rx_filter = HWTSTAMP_FILTER_NONE;
1238	INIT_LIST_HEAD(&ptp->evt_list);
1239	INIT_LIST_HEAD(&ptp->evt_free_list);
1240	spin_lock_init(&ptp->evt_lock);
1241	for (pos = 0; pos < MAX_RECEIVE_EVENTS; pos++)
1242		list_add(&ptp->rx_evts[pos].link, &ptp->evt_free_list);
1243
1244	/* Get the NIC PTP attributes and set up time conversions */
1245	rc = efx_ptp_get_attributes(efx);
1246	if (rc < 0)
1247		goto fail3;
1248
1249	/* Get the timestamp corrections */
1250	rc = efx_ptp_get_timestamp_corrections(efx);
1251	if (rc < 0)
1252		goto fail3;
1253
1254	if (efx->mcdi->fn_flags &
1255	    (1 << MC_CMD_DRV_ATTACH_EXT_OUT_FLAG_PRIMARY)) {
1256		ptp->phc_clock_info = efx_phc_clock_info;
1257		ptp->phc_clock = ptp_clock_register(&ptp->phc_clock_info,
1258						    &efx->pci_dev->dev);
1259		if (IS_ERR(ptp->phc_clock)) {
1260			rc = PTR_ERR(ptp->phc_clock);
1261			goto fail3;
1262		}
1263
1264		INIT_WORK(&ptp->pps_work, efx_ptp_pps_worker);
1265		ptp->pps_workwq = create_singlethread_workqueue("sfc_pps");
1266		if (!ptp->pps_workwq) {
1267			rc = -ENOMEM;
1268			goto fail4;
1269		}
1270	}
1271	ptp->nic_ts_enabled = false;
1272
1273	return 0;
1274fail4:
1275	ptp_clock_unregister(efx->ptp_data->phc_clock);
1276
1277fail3:
1278	destroy_workqueue(efx->ptp_data->workwq);
1279
1280fail2:
1281	efx_nic_free_buffer(efx, &ptp->start);
1282
1283fail1:
1284	kfree(efx->ptp_data);
1285	efx->ptp_data = NULL;
1286
1287	return rc;
1288}
1289
1290/* Initialise PTP channel.
1291 *
1292 * Setting core_index to zero causes the queue to be initialised and doesn't
1293 * overlap with 'rxq0' because ptp.c doesn't use skb_record_rx_queue.
1294 */
1295static int efx_ptp_probe_channel(struct efx_channel *channel)
1296{
1297	struct efx_nic *efx = channel->efx;
1298
1299	channel->irq_moderation = 0;
1300	channel->rx_queue.core_index = 0;
1301
1302	return efx_ptp_probe(efx, channel);
1303}
1304
1305void efx_ptp_remove(struct efx_nic *efx)
1306{
1307	if (!efx->ptp_data)
1308		return;
1309
1310	(void)efx_ptp_disable(efx);
1311
1312	cancel_work_sync(&efx->ptp_data->work);
1313	cancel_work_sync(&efx->ptp_data->pps_work);
1314
1315	skb_queue_purge(&efx->ptp_data->rxq);
1316	skb_queue_purge(&efx->ptp_data->txq);
1317
1318	if (efx->ptp_data->phc_clock) {
1319		destroy_workqueue(efx->ptp_data->pps_workwq);
1320		ptp_clock_unregister(efx->ptp_data->phc_clock);
1321	}
1322
1323	destroy_workqueue(efx->ptp_data->workwq);
1324
1325	efx_nic_free_buffer(efx, &efx->ptp_data->start);
1326	kfree(efx->ptp_data);
1327}
1328
1329static void efx_ptp_remove_channel(struct efx_channel *channel)
1330{
1331	efx_ptp_remove(channel->efx);
1332}
1333
1334static void efx_ptp_get_channel_name(struct efx_channel *channel,
1335				     char *buf, size_t len)
1336{
1337	snprintf(buf, len, "%s-ptp", channel->efx->name);
1338}
1339
1340/* Determine whether this packet should be processed by the PTP module
1341 * or transmitted conventionally.
1342 */
1343bool efx_ptp_is_ptp_tx(struct efx_nic *efx, struct sk_buff *skb)
1344{
1345	return efx->ptp_data &&
1346		efx->ptp_data->enabled &&
1347		skb->len >= PTP_MIN_LENGTH &&
1348		skb->len <= MC_CMD_PTP_IN_TRANSMIT_PACKET_MAXNUM &&
1349		likely(skb->protocol == htons(ETH_P_IP)) &&
1350		skb_transport_header_was_set(skb) &&
1351		skb_network_header_len(skb) >= sizeof(struct iphdr) &&
1352		ip_hdr(skb)->protocol == IPPROTO_UDP &&
1353		skb_headlen(skb) >=
1354		skb_transport_offset(skb) + sizeof(struct udphdr) &&
1355		udp_hdr(skb)->dest == htons(PTP_EVENT_PORT);
1356}
1357
1358/* Receive a PTP packet.  Packets are queued until the arrival of
1359 * the receive timestamp from the MC - this will probably occur after the
1360 * packet arrival because of the processing in the MC.
1361 */
1362static bool efx_ptp_rx(struct efx_channel *channel, struct sk_buff *skb)
1363{
1364	struct efx_nic *efx = channel->efx;
1365	struct efx_ptp_data *ptp = efx->ptp_data;
1366	struct efx_ptp_match *match = (struct efx_ptp_match *)skb->cb;
1367	u8 *match_data_012, *match_data_345;
1368	unsigned int version;
1369	u8 *data;
1370
1371	match->expiry = jiffies + msecs_to_jiffies(PKT_EVENT_LIFETIME_MS);
1372
1373	/* Correct version? */
1374	if (ptp->mode == MC_CMD_PTP_MODE_V1) {
1375		if (!pskb_may_pull(skb, PTP_V1_MIN_LENGTH)) {
1376			return false;
1377		}
1378		data = skb->data;
1379		version = ntohs(*(__be16 *)&data[PTP_V1_VERSION_OFFSET]);
1380		if (version != PTP_VERSION_V1) {
1381			return false;
1382		}
1383
1384		/* PTP V1 uses all six bytes of the UUID to match the packet
1385		 * to the timestamp
1386		 */
1387		match_data_012 = data + PTP_V1_UUID_OFFSET;
1388		match_data_345 = data + PTP_V1_UUID_OFFSET + 3;
1389	} else {
1390		if (!pskb_may_pull(skb, PTP_V2_MIN_LENGTH)) {
1391			return false;
1392		}
1393		data = skb->data;
1394		version = data[PTP_V2_VERSION_OFFSET];
1395		if ((version & PTP_VERSION_V2_MASK) != PTP_VERSION_V2) {
1396			return false;
1397		}
1398
1399		/* The original V2 implementation uses bytes 2-7 of
1400		 * the UUID to match the packet to the timestamp. This
1401		 * discards two of the bytes of the MAC address used
1402		 * to create the UUID (SF bug 33070).  The PTP V2
1403		 * enhanced mode fixes this issue and uses bytes 0-2
1404		 * and byte 5-7 of the UUID.
1405		 */
1406		match_data_345 = data + PTP_V2_UUID_OFFSET + 5;
1407		if (ptp->mode == MC_CMD_PTP_MODE_V2) {
1408			match_data_012 = data + PTP_V2_UUID_OFFSET + 2;
1409		} else {
1410			match_data_012 = data + PTP_V2_UUID_OFFSET + 0;
1411			BUG_ON(ptp->mode != MC_CMD_PTP_MODE_V2_ENHANCED);
1412		}
1413	}
1414
1415	/* Does this packet require timestamping? */
1416	if (ntohs(*(__be16 *)&data[PTP_DPORT_OFFSET]) == PTP_EVENT_PORT) {
1417		match->state = PTP_PACKET_STATE_UNMATCHED;
1418
1419		/* We expect the sequence number to be in the same position in
1420		 * the packet for PTP V1 and V2
1421		 */
1422		BUILD_BUG_ON(PTP_V1_SEQUENCE_OFFSET != PTP_V2_SEQUENCE_OFFSET);
1423		BUILD_BUG_ON(PTP_V1_SEQUENCE_LENGTH != PTP_V2_SEQUENCE_LENGTH);
1424
1425		/* Extract UUID/Sequence information */
1426		match->words[0] = (match_data_012[0]         |
1427				   (match_data_012[1] << 8)  |
1428				   (match_data_012[2] << 16) |
1429				   (match_data_345[0] << 24));
1430		match->words[1] = (match_data_345[1]         |
1431				   (match_data_345[2] << 8)  |
1432				   (data[PTP_V1_SEQUENCE_OFFSET +
1433					 PTP_V1_SEQUENCE_LENGTH - 1] <<
1434				    16));
1435	} else {
1436		match->state = PTP_PACKET_STATE_MATCH_UNWANTED;
1437	}
1438
1439	skb_queue_tail(&ptp->rxq, skb);
1440	queue_work(ptp->workwq, &ptp->work);
1441
1442	return true;
1443}
1444
1445/* Transmit a PTP packet.  This has to be transmitted by the MC
1446 * itself, through an MCDI call.  MCDI calls aren't permitted
1447 * in the transmit path so defer the actual transmission to a suitable worker.
1448 */
1449int efx_ptp_tx(struct efx_nic *efx, struct sk_buff *skb)
1450{
1451	struct efx_ptp_data *ptp = efx->ptp_data;
1452
1453	skb_queue_tail(&ptp->txq, skb);
1454
1455	if ((udp_hdr(skb)->dest == htons(PTP_EVENT_PORT)) &&
1456	    (skb->len <= MC_CMD_PTP_IN_TRANSMIT_PACKET_MAXNUM))
1457		efx_xmit_hwtstamp_pending(skb);
1458	queue_work(ptp->workwq, &ptp->work);
1459
1460	return NETDEV_TX_OK;
1461}
1462
1463int efx_ptp_get_mode(struct efx_nic *efx)
1464{
1465	return efx->ptp_data->mode;
1466}
1467
1468int efx_ptp_change_mode(struct efx_nic *efx, bool enable_wanted,
1469			unsigned int new_mode)
1470{
1471	if ((enable_wanted != efx->ptp_data->enabled) ||
1472	    (enable_wanted && (efx->ptp_data->mode != new_mode))) {
1473		int rc = 0;
1474
1475		if (enable_wanted) {
1476			/* Change of mode requires disable */
1477			if (efx->ptp_data->enabled &&
1478			    (efx->ptp_data->mode != new_mode)) {
1479				efx->ptp_data->enabled = false;
1480				rc = efx_ptp_stop(efx);
1481				if (rc != 0)
1482					return rc;
1483			}
1484
1485			/* Set new operating mode and establish
1486			 * baseline synchronisation, which must
1487			 * succeed.
1488			 */
1489			efx->ptp_data->mode = new_mode;
1490			if (netif_running(efx->net_dev))
1491				rc = efx_ptp_start(efx);
1492			if (rc == 0) {
1493				rc = efx_ptp_synchronize(efx,
1494							 PTP_SYNC_ATTEMPTS * 2);
1495				if (rc != 0)
1496					efx_ptp_stop(efx);
1497			}
1498		} else {
1499			rc = efx_ptp_stop(efx);
1500		}
1501
1502		if (rc != 0)
1503			return rc;
1504
1505		efx->ptp_data->enabled = enable_wanted;
1506	}
1507
1508	return 0;
1509}
1510
1511static int efx_ptp_ts_init(struct efx_nic *efx, struct hwtstamp_config *init)
1512{
1513	int rc;
1514
1515	if (init->flags)
1516		return -EINVAL;
1517
1518	if ((init->tx_type != HWTSTAMP_TX_OFF) &&
1519	    (init->tx_type != HWTSTAMP_TX_ON))
1520		return -ERANGE;
1521
1522	rc = efx->type->ptp_set_ts_config(efx, init);
1523	if (rc)
1524		return rc;
1525
1526	efx->ptp_data->config = *init;
1527	return 0;
1528}
1529
1530void efx_ptp_get_ts_info(struct efx_nic *efx, struct ethtool_ts_info *ts_info)
1531{
1532	struct efx_ptp_data *ptp = efx->ptp_data;
1533	struct efx_nic *primary = efx->primary;
1534
1535	ASSERT_RTNL();
1536
1537	if (!ptp)
1538		return;
1539
1540	ts_info->so_timestamping |= (SOF_TIMESTAMPING_TX_HARDWARE |
1541				     SOF_TIMESTAMPING_RX_HARDWARE |
1542				     SOF_TIMESTAMPING_RAW_HARDWARE);
1543	if (primary && primary->ptp_data && primary->ptp_data->phc_clock)
1544		ts_info->phc_index =
1545			ptp_clock_index(primary->ptp_data->phc_clock);
1546	ts_info->tx_types = 1 << HWTSTAMP_TX_OFF | 1 << HWTSTAMP_TX_ON;
1547	ts_info->rx_filters = ptp->efx->type->hwtstamp_filters;
1548}
1549
1550int efx_ptp_set_ts_config(struct efx_nic *efx, struct ifreq *ifr)
1551{
1552	struct hwtstamp_config config;
1553	int rc;
1554
1555	/* Not a PTP enabled port */
1556	if (!efx->ptp_data)
1557		return -EOPNOTSUPP;
1558
1559	if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
1560		return -EFAULT;
1561
1562	rc = efx_ptp_ts_init(efx, &config);
1563	if (rc != 0)
1564		return rc;
1565
1566	return copy_to_user(ifr->ifr_data, &config, sizeof(config))
1567		? -EFAULT : 0;
1568}
1569
1570int efx_ptp_get_ts_config(struct efx_nic *efx, struct ifreq *ifr)
1571{
1572	if (!efx->ptp_data)
1573		return -EOPNOTSUPP;
1574
1575	return copy_to_user(ifr->ifr_data, &efx->ptp_data->config,
1576			    sizeof(efx->ptp_data->config)) ? -EFAULT : 0;
1577}
1578
1579static void ptp_event_failure(struct efx_nic *efx, int expected_frag_len)
1580{
1581	struct efx_ptp_data *ptp = efx->ptp_data;
1582
1583	netif_err(efx, hw, efx->net_dev,
1584		"PTP unexpected event length: got %d expected %d\n",
1585		ptp->evt_frag_idx, expected_frag_len);
1586	ptp->reset_required = true;
1587	queue_work(ptp->workwq, &ptp->work);
1588}
1589
1590/* Process a completed receive event.  Put it on the event queue and
1591 * start worker thread.  This is required because event and their
1592 * correspoding packets may come in either order.
1593 */
1594static void ptp_event_rx(struct efx_nic *efx, struct efx_ptp_data *ptp)
1595{
1596	struct efx_ptp_event_rx *evt = NULL;
1597
1598	if (WARN_ON_ONCE(ptp->rx_ts_inline))
1599		return;
1600
1601	if (ptp->evt_frag_idx != 3) {
1602		ptp_event_failure(efx, 3);
1603		return;
1604	}
1605
1606	spin_lock_bh(&ptp->evt_lock);
1607	if (!list_empty(&ptp->evt_free_list)) {
1608		evt = list_first_entry(&ptp->evt_free_list,
1609				       struct efx_ptp_event_rx, link);
1610		list_del(&evt->link);
1611
1612		evt->seq0 = EFX_QWORD_FIELD(ptp->evt_frags[2], MCDI_EVENT_DATA);
1613		evt->seq1 = (EFX_QWORD_FIELD(ptp->evt_frags[2],
1614					     MCDI_EVENT_SRC)        |
1615			     (EFX_QWORD_FIELD(ptp->evt_frags[1],
1616					      MCDI_EVENT_SRC) << 8) |
1617			     (EFX_QWORD_FIELD(ptp->evt_frags[0],
1618					      MCDI_EVENT_SRC) << 16));
1619		evt->hwtimestamp = efx->ptp_data->nic_to_kernel_time(
1620			EFX_QWORD_FIELD(ptp->evt_frags[0], MCDI_EVENT_DATA),
1621			EFX_QWORD_FIELD(ptp->evt_frags[1], MCDI_EVENT_DATA),
1622			ptp->ts_corrections.rx);
1623		evt->expiry = jiffies + msecs_to_jiffies(PKT_EVENT_LIFETIME_MS);
1624		list_add_tail(&evt->link, &ptp->evt_list);
1625
1626		queue_work(ptp->workwq, &ptp->work);
1627	} else if (net_ratelimit()) {
1628		/* Log a rate-limited warning message. */
1629		netif_err(efx, rx_err, efx->net_dev, "PTP event queue overflow\n");
1630	}
1631	spin_unlock_bh(&ptp->evt_lock);
1632}
1633
1634static void ptp_event_fault(struct efx_nic *efx, struct efx_ptp_data *ptp)
1635{
1636	int code = EFX_QWORD_FIELD(ptp->evt_frags[0], MCDI_EVENT_DATA);
1637	if (ptp->evt_frag_idx != 1) {
1638		ptp_event_failure(efx, 1);
1639		return;
1640	}
1641
1642	netif_err(efx, hw, efx->net_dev, "PTP error %d\n", code);
1643}
1644
1645static void ptp_event_pps(struct efx_nic *efx, struct efx_ptp_data *ptp)
1646{
1647	if (ptp->nic_ts_enabled)
1648		queue_work(ptp->pps_workwq, &ptp->pps_work);
1649}
1650
1651void efx_ptp_event(struct efx_nic *efx, efx_qword_t *ev)
1652{
1653	struct efx_ptp_data *ptp = efx->ptp_data;
1654	int code = EFX_QWORD_FIELD(*ev, MCDI_EVENT_CODE);
1655
1656	if (!ptp) {
1657		if (net_ratelimit())
1658			netif_warn(efx, drv, efx->net_dev,
1659				   "Received PTP event but PTP not set up\n");
1660		return;
1661	}
1662
1663	if (!ptp->enabled)
1664		return;
1665
1666	if (ptp->evt_frag_idx == 0) {
1667		ptp->evt_code = code;
1668	} else if (ptp->evt_code != code) {
1669		netif_err(efx, hw, efx->net_dev,
1670			  "PTP out of sequence event %d\n", code);
1671		ptp->evt_frag_idx = 0;
1672	}
1673
1674	ptp->evt_frags[ptp->evt_frag_idx++] = *ev;
1675	if (!MCDI_EVENT_FIELD(*ev, CONT)) {
1676		/* Process resulting event */
1677		switch (code) {
1678		case MCDI_EVENT_CODE_PTP_RX:
1679			ptp_event_rx(efx, ptp);
1680			break;
1681		case MCDI_EVENT_CODE_PTP_FAULT:
1682			ptp_event_fault(efx, ptp);
1683			break;
1684		case MCDI_EVENT_CODE_PTP_PPS:
1685			ptp_event_pps(efx, ptp);
1686			break;
1687		default:
1688			netif_err(efx, hw, efx->net_dev,
1689				  "PTP unknown event %d\n", code);
1690			break;
1691		}
1692		ptp->evt_frag_idx = 0;
1693	} else if (MAX_EVENT_FRAGS == ptp->evt_frag_idx) {
1694		netif_err(efx, hw, efx->net_dev,
1695			  "PTP too many event fragments\n");
1696		ptp->evt_frag_idx = 0;
1697	}
1698}
1699
1700void efx_time_sync_event(struct efx_channel *channel, efx_qword_t *ev)
1701{
1702	channel->sync_timestamp_major = MCDI_EVENT_FIELD(*ev, PTP_TIME_MAJOR);
1703	channel->sync_timestamp_minor =
1704		MCDI_EVENT_FIELD(*ev, PTP_TIME_MINOR_26_19) << 19;
1705	/* if sync events have been disabled then we want to silently ignore
1706	 * this event, so throw away result.
1707	 */
1708	(void) cmpxchg(&channel->sync_events_state, SYNC_EVENTS_REQUESTED,
1709		       SYNC_EVENTS_VALID);
1710}
1711
1712/* make some assumptions about the time representation rather than abstract it,
1713 * since we currently only support one type of inline timestamping and only on
1714 * EF10.
1715 */
1716#define MINOR_TICKS_PER_SECOND 0x8000000
1717/* Fuzz factor for sync events to be out of order with RX events */
1718#define FUZZ (MINOR_TICKS_PER_SECOND / 10)
1719#define EXPECTED_SYNC_EVENTS_PER_SECOND 4
1720
1721static inline u32 efx_rx_buf_timestamp_minor(struct efx_nic *efx, const u8 *eh)
1722{
1723#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
1724	return __le32_to_cpup((const __le32 *)(eh + efx->rx_packet_ts_offset));
1725#else
1726	const u8 *data = eh + efx->rx_packet_ts_offset;
1727	return (u32)data[0]       |
1728	       (u32)data[1] << 8  |
1729	       (u32)data[2] << 16 |
1730	       (u32)data[3] << 24;
1731#endif
1732}
1733
1734void __efx_rx_skb_attach_timestamp(struct efx_channel *channel,
1735				   struct sk_buff *skb)
1736{
1737	struct efx_nic *efx = channel->efx;
1738	u32 pkt_timestamp_major, pkt_timestamp_minor;
1739	u32 diff, carry;
1740	struct skb_shared_hwtstamps *timestamps;
1741
1742	pkt_timestamp_minor = (efx_rx_buf_timestamp_minor(efx,
1743							  skb_mac_header(skb)) +
1744			       (u32) efx->ptp_data->ts_corrections.rx) &
1745			      (MINOR_TICKS_PER_SECOND - 1);
1746
1747	/* get the difference between the packet and sync timestamps,
1748	 * modulo one second
1749	 */
1750	diff = (pkt_timestamp_minor - channel->sync_timestamp_minor) &
1751		(MINOR_TICKS_PER_SECOND - 1);
1752	/* do we roll over a second boundary and need to carry the one? */
1753	carry = channel->sync_timestamp_minor + diff > MINOR_TICKS_PER_SECOND ?
1754		1 : 0;
1755
1756	if (diff <= MINOR_TICKS_PER_SECOND / EXPECTED_SYNC_EVENTS_PER_SECOND +
1757		    FUZZ) {
1758		/* packet is ahead of the sync event by a quarter of a second or
1759		 * less (allowing for fuzz)
1760		 */
1761		pkt_timestamp_major = channel->sync_timestamp_major + carry;
1762	} else if (diff >= MINOR_TICKS_PER_SECOND - FUZZ) {
1763		/* packet is behind the sync event but within the fuzz factor.
1764		 * This means the RX packet and sync event crossed as they were
1765		 * placed on the event queue, which can sometimes happen.
1766		 */
1767		pkt_timestamp_major = channel->sync_timestamp_major - 1 + carry;
1768	} else {
1769		/* it's outside tolerance in both directions. this might be
1770		 * indicative of us missing sync events for some reason, so
1771		 * we'll call it an error rather than risk giving a bogus
1772		 * timestamp.
1773		 */
1774		netif_vdbg(efx, drv, efx->net_dev,
1775			  "packet timestamp %x too far from sync event %x:%x\n",
1776			  pkt_timestamp_minor, channel->sync_timestamp_major,
1777			  channel->sync_timestamp_minor);
1778		return;
1779	}
1780
1781	/* attach the timestamps to the skb */
1782	timestamps = skb_hwtstamps(skb);
1783	timestamps->hwtstamp =
1784		efx_ptp_s27_to_ktime(pkt_timestamp_major, pkt_timestamp_minor);
1785}
1786
1787static int efx_phc_adjfreq(struct ptp_clock_info *ptp, s32 delta)
1788{
1789	struct efx_ptp_data *ptp_data = container_of(ptp,
1790						     struct efx_ptp_data,
1791						     phc_clock_info);
1792	struct efx_nic *efx = ptp_data->efx;
1793	MCDI_DECLARE_BUF(inadj, MC_CMD_PTP_IN_ADJUST_LEN);
1794	s64 adjustment_ns;
1795	int rc;
1796
1797	if (delta > MAX_PPB)
1798		delta = MAX_PPB;
1799	else if (delta < -MAX_PPB)
1800		delta = -MAX_PPB;
1801
1802	/* Convert ppb to fixed point ns. */
1803	adjustment_ns = (((s64)delta * PPB_SCALE_WORD) >>
1804			 (PPB_EXTRA_BITS + MAX_PPB_BITS));
1805
1806	MCDI_SET_DWORD(inadj, PTP_IN_OP, MC_CMD_PTP_OP_ADJUST);
1807	MCDI_SET_DWORD(inadj, PTP_IN_PERIPH_ID, 0);
1808	MCDI_SET_QWORD(inadj, PTP_IN_ADJUST_FREQ, adjustment_ns);
1809	MCDI_SET_DWORD(inadj, PTP_IN_ADJUST_SECONDS, 0);
1810	MCDI_SET_DWORD(inadj, PTP_IN_ADJUST_NANOSECONDS, 0);
1811	rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inadj, sizeof(inadj),
1812			  NULL, 0, NULL);
1813	if (rc != 0)
1814		return rc;
1815
1816	ptp_data->current_adjfreq = adjustment_ns;
1817	return 0;
1818}
1819
1820static int efx_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
1821{
1822	u32 nic_major, nic_minor;
1823	struct efx_ptp_data *ptp_data = container_of(ptp,
1824						     struct efx_ptp_data,
1825						     phc_clock_info);
1826	struct efx_nic *efx = ptp_data->efx;
1827	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_ADJUST_LEN);
1828
1829	efx->ptp_data->ns_to_nic_time(delta, &nic_major, &nic_minor);
1830
1831	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_ADJUST);
1832	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
1833	MCDI_SET_QWORD(inbuf, PTP_IN_ADJUST_FREQ, ptp_data->current_adjfreq);
1834	MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_MAJOR, nic_major);
1835	MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_MINOR, nic_minor);
1836	return efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
1837			    NULL, 0, NULL);
1838}
1839
1840static int efx_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
1841{
1842	struct efx_ptp_data *ptp_data = container_of(ptp,
1843						     struct efx_ptp_data,
1844						     phc_clock_info);
1845	struct efx_nic *efx = ptp_data->efx;
1846	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_READ_NIC_TIME_LEN);
1847	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_READ_NIC_TIME_LEN);
1848	int rc;
1849	ktime_t kt;
1850
1851	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_READ_NIC_TIME);
1852	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
1853
1854	rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
1855			  outbuf, sizeof(outbuf), NULL);
1856	if (rc != 0)
1857		return rc;
1858
1859	kt = ptp_data->nic_to_kernel_time(
1860		MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_MAJOR),
1861		MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_MINOR), 0);
1862	*ts = ktime_to_timespec64(kt);
1863	return 0;
1864}
1865
1866static int efx_phc_settime(struct ptp_clock_info *ptp,
1867			   const struct timespec64 *e_ts)
1868{
1869	/* Get the current NIC time, efx_phc_gettime.
1870	 * Subtract from the desired time to get the offset
1871	 * call efx_phc_adjtime with the offset
1872	 */
1873	int rc;
1874	struct timespec64 time_now;
1875	struct timespec64 delta;
1876
1877	rc = efx_phc_gettime(ptp, &time_now);
1878	if (rc != 0)
1879		return rc;
1880
1881	delta = timespec64_sub(*e_ts, time_now);
1882
1883	rc = efx_phc_adjtime(ptp, timespec64_to_ns(&delta));
1884	if (rc != 0)
1885		return rc;
1886
1887	return 0;
1888}
1889
1890static int efx_phc_enable(struct ptp_clock_info *ptp,
1891			  struct ptp_clock_request *request,
1892			  int enable)
1893{
1894	struct efx_ptp_data *ptp_data = container_of(ptp,
1895						     struct efx_ptp_data,
1896						     phc_clock_info);
1897	if (request->type != PTP_CLK_REQ_PPS)
1898		return -EOPNOTSUPP;
1899
1900	ptp_data->nic_ts_enabled = !!enable;
1901	return 0;
1902}
1903
1904static const struct efx_channel_type efx_ptp_channel_type = {
1905	.handle_no_channel	= efx_ptp_handle_no_channel,
1906	.pre_probe		= efx_ptp_probe_channel,
1907	.post_remove		= efx_ptp_remove_channel,
1908	.get_name		= efx_ptp_get_channel_name,
1909	/* no copy operation; there is no need to reallocate this channel */
1910	.receive_skb		= efx_ptp_rx,
1911	.keep_eventq		= false,
1912};
1913
1914void efx_ptp_defer_probe_with_channel(struct efx_nic *efx)
1915{
1916	/* Check whether PTP is implemented on this NIC.  The DISABLE
1917	 * operation will succeed if and only if it is implemented.
1918	 */
1919	if (efx_ptp_disable(efx) == 0)
1920		efx->extra_channel_type[EFX_EXTRA_CHANNEL_PTP] =
1921			&efx_ptp_channel_type;
1922}
1923
1924void efx_ptp_start_datapath(struct efx_nic *efx)
1925{
1926	if (efx_ptp_restart(efx))
1927		netif_err(efx, drv, efx->net_dev, "Failed to restart PTP.\n");
1928	/* re-enable timestamping if it was previously enabled */
1929	if (efx->type->ptp_set_ts_sync_events)
1930		efx->type->ptp_set_ts_sync_events(efx, true, true);
1931}
1932
1933void efx_ptp_stop_datapath(struct efx_nic *efx)
1934{
1935	/* temporarily disable timestamping */
1936	if (efx->type->ptp_set_ts_sync_events)
1937		efx->type->ptp_set_ts_sync_events(efx, false, true);
1938	efx_ptp_stop(efx);
1939}
1940