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/errno.h>
37 #include <linux/ktime.h>
38 #include <linux/module.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 "tx.h"
47 #include "nic.h" /* indirectly includes ptp.h */
48 #include "efx_channels.h"
49 
50 /* Maximum number of events expected to make up a PTP event */
51 #define	MAX_EVENT_FRAGS			3
52 
53 /* Maximum delay, ms, to begin synchronisation */
54 #define	MAX_SYNCHRONISE_WAIT_MS		2
55 
56 /* How long, at most, to spend synchronising */
57 #define	SYNCHRONISE_PERIOD_NS		250000
58 
59 /* How often to update the shared memory time */
60 #define	SYNCHRONISATION_GRANULARITY_NS	200
61 
62 /* Minimum permitted length of a (corrected) synchronisation time */
63 #define	DEFAULT_MIN_SYNCHRONISATION_NS	120
64 
65 /* Maximum permitted length of a (corrected) synchronisation time */
66 #define	MAX_SYNCHRONISATION_NS		1000
67 
68 /* How many (MC) receive events that can be queued */
69 #define	MAX_RECEIVE_EVENTS		8
70 
71 /* Length of (modified) moving average. */
72 #define	AVERAGE_LENGTH			16
73 
74 /* How long an unmatched event or packet can be held */
75 #define PKT_EVENT_LIFETIME_MS		10
76 
77 /* How long unused unicast filters can be held */
78 #define UCAST_FILTER_EXPIRY_JIFFIES	msecs_to_jiffies(30000)
79 
80 /* Offsets into PTP packet for identification.  These offsets are from the
81  * start of the IP header, not the MAC header.  Note that neither PTP V1 nor
82  * PTP V2 permit the use of IPV4 options.
83  */
84 #define PTP_DPORT_OFFSET	22
85 
86 #define PTP_V1_VERSION_LENGTH	2
87 #define PTP_V1_VERSION_OFFSET	28
88 
89 #define PTP_V1_SEQUENCE_LENGTH	2
90 #define PTP_V1_SEQUENCE_OFFSET	58
91 
92 /* The minimum length of a PTP V1 packet for offsets, etc. to be valid:
93  * includes IP header.
94  */
95 #define	PTP_V1_MIN_LENGTH	64
96 
97 #define PTP_V2_VERSION_LENGTH	1
98 #define PTP_V2_VERSION_OFFSET	29
99 
100 #define PTP_V2_SEQUENCE_LENGTH	2
101 #define PTP_V2_SEQUENCE_OFFSET	58
102 
103 /* The minimum length of a PTP V2 packet for offsets, etc. to be valid:
104  * includes IP header.
105  */
106 #define	PTP_V2_MIN_LENGTH	63
107 
108 #define	PTP_MIN_LENGTH		63
109 
110 #define PTP_ADDR_IPV4		0xe0000181	/* 224.0.1.129 */
111 #define PTP_ADDR_IPV6		{0xff, 0x0e, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, \
112 				0, 0x01, 0x81}	/* ff0e::181 */
113 #define PTP_EVENT_PORT		319
114 #define PTP_GENERAL_PORT	320
115 #define PTP_ADDR_ETHER		{0x01, 0x1b, 0x19, 0, 0, 0} /* 01-1B-19-00-00-00 */
116 
117 /* Annoyingly the format of the version numbers are different between
118  * versions 1 and 2 so it isn't possible to simply look for 1 or 2.
119  */
120 #define	PTP_VERSION_V1		1
121 
122 #define	PTP_VERSION_V2		2
123 #define	PTP_VERSION_V2_MASK	0x0f
124 
125 enum ptp_packet_state {
126 	PTP_PACKET_STATE_UNMATCHED = 0,
127 	PTP_PACKET_STATE_MATCHED,
128 	PTP_PACKET_STATE_TIMED_OUT,
129 	PTP_PACKET_STATE_MATCH_UNWANTED
130 };
131 
132 /* NIC synchronised with single word of time only comprising
133  * partial seconds and full nanoseconds: 10^9 ~ 2^30 so 2 bits for seconds.
134  */
135 #define	MC_NANOSECOND_BITS	30
136 #define	MC_NANOSECOND_MASK	((1 << MC_NANOSECOND_BITS) - 1)
137 #define	MC_SECOND_MASK		((1 << (32 - MC_NANOSECOND_BITS)) - 1)
138 
139 /* Maximum parts-per-billion adjustment that is acceptable */
140 #define MAX_PPB			1000000
141 
142 /* Precalculate scale word to avoid long long division at runtime */
143 /* This is equivalent to 2^66 / 10^9. */
144 #define PPB_SCALE_WORD  ((1LL << (57)) / 1953125LL)
145 
146 /* How much to shift down after scaling to convert to FP40 */
147 #define PPB_SHIFT_FP40		26
148 /* ... and FP44. */
149 #define PPB_SHIFT_FP44		22
150 
151 #define PTP_SYNC_ATTEMPTS	4
152 
153 /**
154  * struct efx_ptp_match - Matching structure, stored in sk_buff's cb area.
155  * @expiry: Time after which the packet should be delivered irrespective of
156  *            event arrival.
157  * @state: The state of the packet - whether it is ready for processing or
158  *         whether that is of no interest.
159  */
160 struct efx_ptp_match {
161 	unsigned long expiry;
162 	enum ptp_packet_state state;
163 };
164 
165 /**
166  * struct efx_ptp_event_rx - A PTP receive event (from MC)
167  * @link: list of events
168  * @seq0: First part of (PTP) UUID
169  * @seq1: Second part of (PTP) UUID and sequence number
170  * @hwtimestamp: Event timestamp
171  * @expiry: Time which the packet arrived
172  */
173 struct efx_ptp_event_rx {
174 	struct list_head link;
175 	u32 seq0;
176 	u32 seq1;
177 	ktime_t hwtimestamp;
178 	unsigned long expiry;
179 };
180 
181 /**
182  * struct efx_ptp_timeset - Synchronisation between host and MC
183  * @host_start: Host time immediately before hardware timestamp taken
184  * @major: Hardware timestamp, major
185  * @minor: Hardware timestamp, minor
186  * @host_end: Host time immediately after hardware timestamp taken
187  * @wait: Number of NIC clock ticks between hardware timestamp being read and
188  *          host end time being seen
189  * @window: Difference of host_end and host_start
190  * @valid: Whether this timeset is valid
191  */
192 struct efx_ptp_timeset {
193 	u32 host_start;
194 	u32 major;
195 	u32 minor;
196 	u32 host_end;
197 	u32 wait;
198 	u32 window;	/* Derived: end - start, allowing for wrap */
199 };
200 
201 /**
202  * struct efx_ptp_rxfilter - Filter for PTP packets
203  * @list: Node of the list where the filter is added
204  * @ether_type: Network protocol of the filter (ETHER_P_IP / ETHER_P_IPV6)
205  * @loc_port: UDP port of the filter (PTP_EVENT_PORT / PTP_GENERAL_PORT)
206  * @loc_host: IPv4/v6 address of the filter
207  * @expiry: time when the filter expires, in jiffies
208  * @handle: Handle ID for the MCDI filters table
209  */
210 struct efx_ptp_rxfilter {
211 	struct list_head list;
212 	__be16 ether_type;
213 	__be16 loc_port;
214 	__be32 loc_host[4];
215 	unsigned long expiry;
216 	int handle;
217 };
218 
219 /**
220  * struct efx_ptp_data - Precision Time Protocol (PTP) state
221  * @efx: The NIC context
222  * @channel: The PTP channel (for Medford and Medford2)
223  * @rxq: Receive SKB queue (awaiting timestamps)
224  * @txq: Transmit SKB queue
225  * @workwq: Work queue for processing pending PTP operations
226  * @work: Work task
227  * @cleanup_work: Work task for periodic cleanup
228  * @reset_required: A serious error has occurred and the PTP task needs to be
229  *                  reset (disable, enable).
230  * @rxfilters_mcast: Receive filters for multicast PTP packets
231  * @rxfilters_ucast: Receive filters for unicast PTP packets
232  * @config: Current timestamp configuration
233  * @enabled: PTP operation enabled
234  * @mode: Mode in which PTP operating (PTP version)
235  * @ns_to_nic_time: Function to convert from scalar nanoseconds to NIC time
236  * @nic_to_kernel_time: Function to convert from NIC to kernel time
237  * @nic_time: contains time details
238  * @nic_time.minor_max: Wrap point for NIC minor times
239  * @nic_time.sync_event_diff_min: Minimum acceptable difference between time
240  * in packet prefix and last MCDI time sync event i.e. how much earlier than
241  * the last sync event time a packet timestamp can be.
242  * @nic_time.sync_event_diff_max: Maximum acceptable difference between time
243  * in packet prefix and last MCDI time sync event i.e. how much later than
244  * the last sync event time a packet timestamp can be.
245  * @nic_time.sync_event_minor_shift: Shift required to make minor time from
246  * field in MCDI time sync event.
247  * @min_synchronisation_ns: Minimum acceptable corrected sync window
248  * @capabilities: Capabilities flags from the NIC
249  * @ts_corrections: contains corrections details
250  * @ts_corrections.ptp_tx: Required driver correction of PTP packet transmit
251  *                         timestamps
252  * @ts_corrections.ptp_rx: Required driver correction of PTP packet receive
253  *                         timestamps
254  * @ts_corrections.pps_out: PPS output error (information only)
255  * @ts_corrections.pps_in: Required driver correction of PPS input timestamps
256  * @ts_corrections.general_tx: Required driver correction of general packet
257  *                             transmit timestamps
258  * @ts_corrections.general_rx: Required driver correction of general packet
259  *                             receive timestamps
260  * @evt_frags: Partly assembled PTP events
261  * @evt_frag_idx: Current fragment number
262  * @evt_code: Last event code
263  * @start: Address at which MC indicates ready for synchronisation
264  * @host_time_pps: Host time at last PPS
265  * @adjfreq_ppb_shift: Shift required to convert scaled parts-per-billion
266  * frequency adjustment into a fixed point fractional nanosecond format.
267  * @current_adjfreq: Current ppb adjustment.
268  * @phc_clock: Pointer to registered phc device (if primary function)
269  * @phc_clock_info: Registration structure for phc device
270  * @pps_work: pps work task for handling pps events
271  * @pps_workwq: pps work queue
272  * @nic_ts_enabled: Flag indicating if NIC generated TS events are handled
273  * @txbuf: Buffer for use when transmitting (PTP) packets to MC (avoids
274  *         allocations in main data path).
275  * @good_syncs: Number of successful synchronisations.
276  * @fast_syncs: Number of synchronisations requiring short delay
277  * @bad_syncs: Number of failed synchronisations.
278  * @sync_timeouts: Number of synchronisation timeouts
279  * @no_time_syncs: Number of synchronisations with no good times.
280  * @invalid_sync_windows: Number of sync windows with bad durations.
281  * @undersize_sync_windows: Number of corrected sync windows that are too small
282  * @oversize_sync_windows: Number of corrected sync windows that are too large
283  * @rx_no_timestamp: Number of packets received without a timestamp.
284  * @timeset: Last set of synchronisation statistics.
285  * @xmit_skb: Transmit SKB function.
286  */
287 struct efx_ptp_data {
288 	struct efx_nic *efx;
289 	struct efx_channel *channel;
290 	struct sk_buff_head rxq;
291 	struct sk_buff_head txq;
292 	struct workqueue_struct *workwq;
293 	struct work_struct work;
294 	struct delayed_work cleanup_work;
295 	bool reset_required;
296 	struct list_head rxfilters_mcast;
297 	struct list_head rxfilters_ucast;
298 	struct hwtstamp_config config;
299 	bool enabled;
300 	unsigned int mode;
301 	void (*ns_to_nic_time)(s64 ns, u32 *nic_major, u32 *nic_minor);
302 	ktime_t (*nic_to_kernel_time)(u32 nic_major, u32 nic_minor,
303 				      s32 correction);
304 	struct {
305 		u32 minor_max;
306 		u32 sync_event_diff_min;
307 		u32 sync_event_diff_max;
308 		unsigned int sync_event_minor_shift;
309 	} nic_time;
310 	unsigned int min_synchronisation_ns;
311 	unsigned int capabilities;
312 	struct {
313 		s32 ptp_tx;
314 		s32 ptp_rx;
315 		s32 pps_out;
316 		s32 pps_in;
317 		s32 general_tx;
318 		s32 general_rx;
319 	} ts_corrections;
320 	efx_qword_t evt_frags[MAX_EVENT_FRAGS];
321 	int evt_frag_idx;
322 	int evt_code;
323 	struct efx_buffer start;
324 	struct pps_event_time host_time_pps;
325 	unsigned int adjfreq_ppb_shift;
326 	s64 current_adjfreq;
327 	struct ptp_clock *phc_clock;
328 	struct ptp_clock_info phc_clock_info;
329 	struct work_struct pps_work;
330 	struct workqueue_struct *pps_workwq;
331 	bool nic_ts_enabled;
332 	efx_dword_t txbuf[MCDI_TX_BUF_LEN(MC_CMD_PTP_IN_TRANSMIT_LENMAX)];
333 
334 	unsigned int good_syncs;
335 	unsigned int fast_syncs;
336 	unsigned int bad_syncs;
337 	unsigned int sync_timeouts;
338 	unsigned int no_time_syncs;
339 	unsigned int invalid_sync_windows;
340 	unsigned int undersize_sync_windows;
341 	unsigned int oversize_sync_windows;
342 	unsigned int rx_no_timestamp;
343 	struct efx_ptp_timeset
344 	timeset[MC_CMD_PTP_OUT_SYNCHRONIZE_TIMESET_MAXNUM];
345 	void (*xmit_skb)(struct efx_nic *efx, struct sk_buff *skb);
346 };
347 
348 static int efx_phc_adjfine(struct ptp_clock_info *ptp, long scaled_ppm);
349 static int efx_phc_adjtime(struct ptp_clock_info *ptp, s64 delta);
350 static int efx_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts);
351 static int efx_phc_settime(struct ptp_clock_info *ptp,
352 			   const struct timespec64 *e_ts);
353 static int efx_phc_enable(struct ptp_clock_info *ptp,
354 			  struct ptp_clock_request *request, int on);
355 static int efx_ptp_insert_unicast_filter(struct efx_nic *efx,
356 					 struct sk_buff *skb);
357 
efx_ptp_use_mac_tx_timestamps(struct efx_nic * efx)358 bool efx_ptp_use_mac_tx_timestamps(struct efx_nic *efx)
359 {
360 	return efx_has_cap(efx, TX_MAC_TIMESTAMPING);
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  */
efx_ptp_want_txqs(struct efx_channel * channel)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 
efx_ptp_describe_stats(struct efx_nic * efx,u8 * strings)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 
efx_ptp_update_stats(struct efx_nic * efx,u64 * stats)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 /* To convert from s27 format to ns we multiply then divide by a power of 2.
441  * For the conversion from ns to s27, the operation is also converted to a
442  * multiply and shift.
443  */
444 #define S27_TO_NS_SHIFT	(27)
445 #define NS_TO_S27_MULT	(((1ULL << 63) + NSEC_PER_SEC / 2) / NSEC_PER_SEC)
446 #define NS_TO_S27_SHIFT	(63 - S27_TO_NS_SHIFT)
447 #define S27_MINOR_MAX	(1 << S27_TO_NS_SHIFT)
448 
449 /* For Huntington platforms NIC time is in seconds and fractions of a second
450  * where the minor register only uses 27 bits in units of 2^-27s.
451  */
efx_ptp_ns_to_s27(s64 ns,u32 * nic_major,u32 * nic_minor)452 static void efx_ptp_ns_to_s27(s64 ns, u32 *nic_major, u32 *nic_minor)
453 {
454 	struct timespec64 ts = ns_to_timespec64(ns);
455 	u32 maj = (u32)ts.tv_sec;
456 	u32 min = (u32)(((u64)ts.tv_nsec * NS_TO_S27_MULT +
457 			 (1ULL << (NS_TO_S27_SHIFT - 1))) >> NS_TO_S27_SHIFT);
458 
459 	/* The conversion can result in the minor value exceeding the maximum.
460 	 * In this case, round up to the next second.
461 	 */
462 	if (min >= S27_MINOR_MAX) {
463 		min -= S27_MINOR_MAX;
464 		maj++;
465 	}
466 
467 	*nic_major = maj;
468 	*nic_minor = min;
469 }
470 
efx_ptp_s27_to_ktime(u32 nic_major,u32 nic_minor)471 static inline ktime_t efx_ptp_s27_to_ktime(u32 nic_major, u32 nic_minor)
472 {
473 	u32 ns = (u32)(((u64)nic_minor * NSEC_PER_SEC +
474 			(1ULL << (S27_TO_NS_SHIFT - 1))) >> S27_TO_NS_SHIFT);
475 	return ktime_set(nic_major, ns);
476 }
477 
efx_ptp_s27_to_ktime_correction(u32 nic_major,u32 nic_minor,s32 correction)478 static ktime_t efx_ptp_s27_to_ktime_correction(u32 nic_major, u32 nic_minor,
479 					       s32 correction)
480 {
481 	/* Apply the correction and deal with carry */
482 	nic_minor += correction;
483 	if ((s32)nic_minor < 0) {
484 		nic_minor += S27_MINOR_MAX;
485 		nic_major--;
486 	} else if (nic_minor >= S27_MINOR_MAX) {
487 		nic_minor -= S27_MINOR_MAX;
488 		nic_major++;
489 	}
490 
491 	return efx_ptp_s27_to_ktime(nic_major, nic_minor);
492 }
493 
494 /* For Medford2 platforms the time is in seconds and quarter nanoseconds. */
efx_ptp_ns_to_s_qns(s64 ns,u32 * nic_major,u32 * nic_minor)495 static void efx_ptp_ns_to_s_qns(s64 ns, u32 *nic_major, u32 *nic_minor)
496 {
497 	struct timespec64 ts = ns_to_timespec64(ns);
498 
499 	*nic_major = (u32)ts.tv_sec;
500 	*nic_minor = ts.tv_nsec * 4;
501 }
502 
efx_ptp_s_qns_to_ktime_correction(u32 nic_major,u32 nic_minor,s32 correction)503 static ktime_t efx_ptp_s_qns_to_ktime_correction(u32 nic_major, u32 nic_minor,
504 						 s32 correction)
505 {
506 	ktime_t kt;
507 
508 	nic_minor = DIV_ROUND_CLOSEST(nic_minor, 4);
509 	correction = DIV_ROUND_CLOSEST(correction, 4);
510 
511 	kt = ktime_set(nic_major, nic_minor);
512 
513 	if (correction >= 0)
514 		kt = ktime_add_ns(kt, (u64)correction);
515 	else
516 		kt = ktime_sub_ns(kt, (u64)-correction);
517 	return kt;
518 }
519 
efx_ptp_channel(struct efx_nic * efx)520 struct efx_channel *efx_ptp_channel(struct efx_nic *efx)
521 {
522 	return efx->ptp_data ? efx->ptp_data->channel : NULL;
523 }
524 
efx_ptp_update_channel(struct efx_nic * efx,struct efx_channel * channel)525 void efx_ptp_update_channel(struct efx_nic *efx, struct efx_channel *channel)
526 {
527 	if (efx->ptp_data)
528 		efx->ptp_data->channel = channel;
529 }
530 
last_sync_timestamp_major(struct efx_nic * efx)531 static u32 last_sync_timestamp_major(struct efx_nic *efx)
532 {
533 	struct efx_channel *channel = efx_ptp_channel(efx);
534 	u32 major = 0;
535 
536 	if (channel)
537 		major = channel->sync_timestamp_major;
538 	return major;
539 }
540 
541 /* The 8000 series and later can provide the time from the MAC, which is only
542  * 48 bits long and provides meta-information in the top 2 bits.
543  */
544 static ktime_t
efx_ptp_mac_nic_to_ktime_correction(struct efx_nic * efx,struct efx_ptp_data * ptp,u32 nic_major,u32 nic_minor,s32 correction)545 efx_ptp_mac_nic_to_ktime_correction(struct efx_nic *efx,
546 				    struct efx_ptp_data *ptp,
547 				    u32 nic_major, u32 nic_minor,
548 				    s32 correction)
549 {
550 	u32 sync_timestamp;
551 	ktime_t kt = { 0 };
552 	s16 delta;
553 
554 	if (!(nic_major & 0x80000000)) {
555 		WARN_ON_ONCE(nic_major >> 16);
556 
557 		/* Medford provides 48 bits of timestamp, so we must get the top
558 		 * 16 bits from the timesync event state.
559 		 *
560 		 * We only have the lower 16 bits of the time now, but we do
561 		 * have a full resolution timestamp at some point in past. As
562 		 * long as the difference between the (real) now and the sync
563 		 * is less than 2^15, then we can reconstruct the difference
564 		 * between those two numbers using only the lower 16 bits of
565 		 * each.
566 		 *
567 		 * Put another way
568 		 *
569 		 * a - b = ((a mod k) - b) mod k
570 		 *
571 		 * when -k/2 < (a-b) < k/2. In our case k is 2^16. We know
572 		 * (a mod k) and b, so can calculate the delta, a - b.
573 		 *
574 		 */
575 		sync_timestamp = last_sync_timestamp_major(efx);
576 
577 		/* Because delta is s16 this does an implicit mask down to
578 		 * 16 bits which is what we need, assuming
579 		 * MEDFORD_TX_SECS_EVENT_BITS is 16. delta is signed so that
580 		 * we can deal with the (unlikely) case of sync timestamps
581 		 * arriving from the future.
582 		 */
583 		delta = nic_major - sync_timestamp;
584 
585 		/* Recover the fully specified time now, by applying the offset
586 		 * to the (fully specified) sync time.
587 		 */
588 		nic_major = sync_timestamp + delta;
589 
590 		kt = ptp->nic_to_kernel_time(nic_major, nic_minor,
591 					     correction);
592 	}
593 	return kt;
594 }
595 
efx_ptp_nic_to_kernel_time(struct efx_tx_queue * tx_queue)596 ktime_t efx_ptp_nic_to_kernel_time(struct efx_tx_queue *tx_queue)
597 {
598 	struct efx_nic *efx = tx_queue->efx;
599 	struct efx_ptp_data *ptp = efx->ptp_data;
600 	ktime_t kt;
601 
602 	if (efx_ptp_use_mac_tx_timestamps(efx))
603 		kt = efx_ptp_mac_nic_to_ktime_correction(efx, ptp,
604 				tx_queue->completed_timestamp_major,
605 				tx_queue->completed_timestamp_minor,
606 				ptp->ts_corrections.general_tx);
607 	else
608 		kt = ptp->nic_to_kernel_time(
609 				tx_queue->completed_timestamp_major,
610 				tx_queue->completed_timestamp_minor,
611 				ptp->ts_corrections.general_tx);
612 	return kt;
613 }
614 
615 /* Get PTP attributes and set up time conversions */
efx_ptp_get_attributes(struct efx_nic * efx)616 static int efx_ptp_get_attributes(struct efx_nic *efx)
617 {
618 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_GET_ATTRIBUTES_LEN);
619 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_GET_ATTRIBUTES_LEN);
620 	struct efx_ptp_data *ptp = efx->ptp_data;
621 	int rc;
622 	u32 fmt;
623 	size_t out_len;
624 
625 	/* Get the PTP attributes. If the NIC doesn't support the operation we
626 	 * use the default format for compatibility with older NICs i.e.
627 	 * seconds and nanoseconds.
628 	 */
629 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_GET_ATTRIBUTES);
630 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
631 	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
632 				outbuf, sizeof(outbuf), &out_len);
633 	if (rc == 0) {
634 		fmt = MCDI_DWORD(outbuf, PTP_OUT_GET_ATTRIBUTES_TIME_FORMAT);
635 	} else if (rc == -EINVAL) {
636 		fmt = MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_NANOSECONDS;
637 	} else if (rc == -EPERM) {
638 		pci_info(efx->pci_dev, "no PTP support\n");
639 		return rc;
640 	} else {
641 		efx_mcdi_display_error(efx, MC_CMD_PTP, sizeof(inbuf),
642 				       outbuf, sizeof(outbuf), rc);
643 		return rc;
644 	}
645 
646 	switch (fmt) {
647 	case MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_27FRACTION:
648 		ptp->ns_to_nic_time = efx_ptp_ns_to_s27;
649 		ptp->nic_to_kernel_time = efx_ptp_s27_to_ktime_correction;
650 		ptp->nic_time.minor_max = 1 << 27;
651 		ptp->nic_time.sync_event_minor_shift = 19;
652 		break;
653 	case MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_QTR_NANOSECONDS:
654 		ptp->ns_to_nic_time = efx_ptp_ns_to_s_qns;
655 		ptp->nic_to_kernel_time = efx_ptp_s_qns_to_ktime_correction;
656 		ptp->nic_time.minor_max = 4000000000UL;
657 		ptp->nic_time.sync_event_minor_shift = 24;
658 		break;
659 	default:
660 		return -ERANGE;
661 	}
662 
663 	/* Precalculate acceptable difference between the minor time in the
664 	 * packet prefix and the last MCDI time sync event. We expect the
665 	 * packet prefix timestamp to be after of sync event by up to one
666 	 * sync event interval (0.25s) but we allow it to exceed this by a
667 	 * fuzz factor of (0.1s)
668 	 */
669 	ptp->nic_time.sync_event_diff_min = ptp->nic_time.minor_max
670 		- (ptp->nic_time.minor_max / 10);
671 	ptp->nic_time.sync_event_diff_max = (ptp->nic_time.minor_max / 4)
672 		+ (ptp->nic_time.minor_max / 10);
673 
674 	/* MC_CMD_PTP_OP_GET_ATTRIBUTES has been extended twice from an older
675 	 * operation MC_CMD_PTP_OP_GET_TIME_FORMAT. The function now may return
676 	 * a value to use for the minimum acceptable corrected synchronization
677 	 * window and may return further capabilities.
678 	 * If we have the extra information store it. For older firmware that
679 	 * does not implement the extended command use the default value.
680 	 */
681 	if (rc == 0 &&
682 	    out_len >= MC_CMD_PTP_OUT_GET_ATTRIBUTES_CAPABILITIES_OFST)
683 		ptp->min_synchronisation_ns =
684 			MCDI_DWORD(outbuf,
685 				   PTP_OUT_GET_ATTRIBUTES_SYNC_WINDOW_MIN);
686 	else
687 		ptp->min_synchronisation_ns = DEFAULT_MIN_SYNCHRONISATION_NS;
688 
689 	if (rc == 0 &&
690 	    out_len >= MC_CMD_PTP_OUT_GET_ATTRIBUTES_LEN)
691 		ptp->capabilities = MCDI_DWORD(outbuf,
692 					PTP_OUT_GET_ATTRIBUTES_CAPABILITIES);
693 	else
694 		ptp->capabilities = 0;
695 
696 	/* Set up the shift for conversion between frequency
697 	 * adjustments in parts-per-billion and the fixed-point
698 	 * fractional ns format that the adapter uses.
699 	 */
700 	if (ptp->capabilities & (1 << MC_CMD_PTP_OUT_GET_ATTRIBUTES_FP44_FREQ_ADJ_LBN))
701 		ptp->adjfreq_ppb_shift = PPB_SHIFT_FP44;
702 	else
703 		ptp->adjfreq_ppb_shift = PPB_SHIFT_FP40;
704 
705 	return 0;
706 }
707 
708 /* Get PTP timestamp corrections */
efx_ptp_get_timestamp_corrections(struct efx_nic * efx)709 static int efx_ptp_get_timestamp_corrections(struct efx_nic *efx)
710 {
711 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_GET_TIMESTAMP_CORRECTIONS_LEN);
712 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_LEN);
713 	int rc;
714 	size_t out_len;
715 
716 	/* Get the timestamp corrections from the NIC. If this operation is
717 	 * not supported (older NICs) then no correction is required.
718 	 */
719 	MCDI_SET_DWORD(inbuf, PTP_IN_OP,
720 		       MC_CMD_PTP_OP_GET_TIMESTAMP_CORRECTIONS);
721 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
722 
723 	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
724 				outbuf, sizeof(outbuf), &out_len);
725 	if (rc == 0) {
726 		efx->ptp_data->ts_corrections.ptp_tx = MCDI_DWORD(outbuf,
727 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_TRANSMIT);
728 		efx->ptp_data->ts_corrections.ptp_rx = MCDI_DWORD(outbuf,
729 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_RECEIVE);
730 		efx->ptp_data->ts_corrections.pps_out = MCDI_DWORD(outbuf,
731 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_PPS_OUT);
732 		efx->ptp_data->ts_corrections.pps_in = MCDI_DWORD(outbuf,
733 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_PPS_IN);
734 
735 		if (out_len >= MC_CMD_PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_LEN) {
736 			efx->ptp_data->ts_corrections.general_tx = MCDI_DWORD(
737 				outbuf,
738 				PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_GENERAL_TX);
739 			efx->ptp_data->ts_corrections.general_rx = MCDI_DWORD(
740 				outbuf,
741 				PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_GENERAL_RX);
742 		} else {
743 			efx->ptp_data->ts_corrections.general_tx =
744 				efx->ptp_data->ts_corrections.ptp_tx;
745 			efx->ptp_data->ts_corrections.general_rx =
746 				efx->ptp_data->ts_corrections.ptp_rx;
747 		}
748 	} else if (rc == -EINVAL) {
749 		efx->ptp_data->ts_corrections.ptp_tx = 0;
750 		efx->ptp_data->ts_corrections.ptp_rx = 0;
751 		efx->ptp_data->ts_corrections.pps_out = 0;
752 		efx->ptp_data->ts_corrections.pps_in = 0;
753 		efx->ptp_data->ts_corrections.general_tx = 0;
754 		efx->ptp_data->ts_corrections.general_rx = 0;
755 	} else {
756 		efx_mcdi_display_error(efx, MC_CMD_PTP, sizeof(inbuf), outbuf,
757 				       sizeof(outbuf), rc);
758 		return rc;
759 	}
760 
761 	return 0;
762 }
763 
764 /* Enable MCDI PTP support. */
efx_ptp_enable(struct efx_nic * efx)765 static int efx_ptp_enable(struct efx_nic *efx)
766 {
767 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_ENABLE_LEN);
768 	MCDI_DECLARE_BUF_ERR(outbuf);
769 	int rc;
770 
771 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_ENABLE);
772 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
773 	MCDI_SET_DWORD(inbuf, PTP_IN_ENABLE_QUEUE,
774 		       efx->ptp_data->channel ?
775 		       efx->ptp_data->channel->channel : 0);
776 	MCDI_SET_DWORD(inbuf, PTP_IN_ENABLE_MODE, efx->ptp_data->mode);
777 
778 	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
779 				outbuf, sizeof(outbuf), NULL);
780 	rc = (rc == -EALREADY) ? 0 : rc;
781 	if (rc)
782 		efx_mcdi_display_error(efx, MC_CMD_PTP,
783 				       MC_CMD_PTP_IN_ENABLE_LEN,
784 				       outbuf, sizeof(outbuf), rc);
785 	return rc;
786 }
787 
788 /* Disable MCDI PTP support.
789  *
790  * Note that this function should never rely on the presence of ptp_data -
791  * may be called before that exists.
792  */
efx_ptp_disable(struct efx_nic * efx)793 static int efx_ptp_disable(struct efx_nic *efx)
794 {
795 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_DISABLE_LEN);
796 	MCDI_DECLARE_BUF_ERR(outbuf);
797 	int rc;
798 
799 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_DISABLE);
800 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
801 	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
802 				outbuf, sizeof(outbuf), NULL);
803 	rc = (rc == -EALREADY) ? 0 : rc;
804 	/* If we get ENOSYS, the NIC doesn't support PTP, and thus this function
805 	 * should only have been called during probe.
806 	 */
807 	if (rc == -ENOSYS || rc == -EPERM)
808 		pci_info(efx->pci_dev, "no PTP support\n");
809 	else if (rc)
810 		efx_mcdi_display_error(efx, MC_CMD_PTP,
811 				       MC_CMD_PTP_IN_DISABLE_LEN,
812 				       outbuf, sizeof(outbuf), rc);
813 	return rc;
814 }
815 
efx_ptp_deliver_rx_queue(struct sk_buff_head * q)816 static void efx_ptp_deliver_rx_queue(struct sk_buff_head *q)
817 {
818 	struct sk_buff *skb;
819 
820 	while ((skb = skb_dequeue(q))) {
821 		local_bh_disable();
822 		netif_receive_skb(skb);
823 		local_bh_enable();
824 	}
825 }
826 
efx_ptp_handle_no_channel(struct efx_nic * efx)827 static void efx_ptp_handle_no_channel(struct efx_nic *efx)
828 {
829 	netif_err(efx, drv, efx->net_dev,
830 		  "ERROR: PTP requires MSI-X and 1 additional interrupt"
831 		  "vector. PTP disabled\n");
832 }
833 
834 /* Repeatedly send the host time to the MC which will capture the hardware
835  * time.
836  */
efx_ptp_send_times(struct efx_nic * efx,struct pps_event_time * last_time)837 static void efx_ptp_send_times(struct efx_nic *efx,
838 			       struct pps_event_time *last_time)
839 {
840 	struct pps_event_time now;
841 	struct timespec64 limit;
842 	struct efx_ptp_data *ptp = efx->ptp_data;
843 	int *mc_running = ptp->start.addr;
844 
845 	pps_get_ts(&now);
846 	limit = now.ts_real;
847 	timespec64_add_ns(&limit, SYNCHRONISE_PERIOD_NS);
848 
849 	/* Write host time for specified period or until MC is done */
850 	while ((timespec64_compare(&now.ts_real, &limit) < 0) &&
851 	       READ_ONCE(*mc_running)) {
852 		struct timespec64 update_time;
853 		unsigned int host_time;
854 
855 		/* Don't update continuously to avoid saturating the PCIe bus */
856 		update_time = now.ts_real;
857 		timespec64_add_ns(&update_time, SYNCHRONISATION_GRANULARITY_NS);
858 		do {
859 			pps_get_ts(&now);
860 		} while ((timespec64_compare(&now.ts_real, &update_time) < 0) &&
861 			 READ_ONCE(*mc_running));
862 
863 		/* Synchronise NIC with single word of time only */
864 		host_time = (now.ts_real.tv_sec << MC_NANOSECOND_BITS |
865 			     now.ts_real.tv_nsec);
866 		/* Update host time in NIC memory */
867 		efx->type->ptp_write_host_time(efx, host_time);
868 	}
869 	*last_time = now;
870 }
871 
872 /* Read a timeset from the MC's results and partial process. */
efx_ptp_read_timeset(MCDI_DECLARE_STRUCT_PTR (data),struct efx_ptp_timeset * timeset)873 static void efx_ptp_read_timeset(MCDI_DECLARE_STRUCT_PTR(data),
874 				 struct efx_ptp_timeset *timeset)
875 {
876 	unsigned start_ns, end_ns;
877 
878 	timeset->host_start = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTSTART);
879 	timeset->major = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_MAJOR);
880 	timeset->minor = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_MINOR);
881 	timeset->host_end = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTEND),
882 	timeset->wait = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_WAITNS);
883 
884 	/* Ignore seconds */
885 	start_ns = timeset->host_start & MC_NANOSECOND_MASK;
886 	end_ns = timeset->host_end & MC_NANOSECOND_MASK;
887 	/* Allow for rollover */
888 	if (end_ns < start_ns)
889 		end_ns += NSEC_PER_SEC;
890 	/* Determine duration of operation */
891 	timeset->window = end_ns - start_ns;
892 }
893 
894 /* Process times received from MC.
895  *
896  * Extract times from returned results, and establish the minimum value
897  * seen.  The minimum value represents the "best" possible time and events
898  * too much greater than this are rejected - the machine is, perhaps, too
899  * busy. A number of readings are taken so that, hopefully, at least one good
900  * synchronisation will be seen in the results.
901  */
902 static int
efx_ptp_process_times(struct efx_nic * efx,MCDI_DECLARE_STRUCT_PTR (synch_buf),size_t response_length,const struct pps_event_time * last_time)903 efx_ptp_process_times(struct efx_nic *efx, MCDI_DECLARE_STRUCT_PTR(synch_buf),
904 		      size_t response_length,
905 		      const struct pps_event_time *last_time)
906 {
907 	unsigned number_readings =
908 		MCDI_VAR_ARRAY_LEN(response_length,
909 				   PTP_OUT_SYNCHRONIZE_TIMESET);
910 	unsigned i;
911 	unsigned ngood = 0;
912 	unsigned last_good = 0;
913 	struct efx_ptp_data *ptp = efx->ptp_data;
914 	u32 last_sec;
915 	u32 start_sec;
916 	struct timespec64 delta;
917 	ktime_t mc_time;
918 
919 	if (number_readings == 0)
920 		return -EAGAIN;
921 
922 	/* Read the set of results and find the last good host-MC
923 	 * synchronization result. The MC times when it finishes reading the
924 	 * host time so the corrected window time should be fairly constant
925 	 * for a given platform. Increment stats for any results that appear
926 	 * to be erroneous.
927 	 */
928 	for (i = 0; i < number_readings; i++) {
929 		s32 window, corrected;
930 		struct timespec64 wait;
931 
932 		efx_ptp_read_timeset(
933 			MCDI_ARRAY_STRUCT_PTR(synch_buf,
934 					      PTP_OUT_SYNCHRONIZE_TIMESET, i),
935 			&ptp->timeset[i]);
936 
937 		wait = ktime_to_timespec64(
938 			ptp->nic_to_kernel_time(0, ptp->timeset[i].wait, 0));
939 		window = ptp->timeset[i].window;
940 		corrected = window - wait.tv_nsec;
941 
942 		/* We expect the uncorrected synchronization window to be at
943 		 * least as large as the interval between host start and end
944 		 * times. If it is smaller than this then this is mostly likely
945 		 * to be a consequence of the host's time being adjusted.
946 		 * Check that the corrected sync window is in a reasonable
947 		 * range. If it is out of range it is likely to be because an
948 		 * interrupt or other delay occurred between reading the system
949 		 * time and writing it to MC memory.
950 		 */
951 		if (window < SYNCHRONISATION_GRANULARITY_NS) {
952 			++ptp->invalid_sync_windows;
953 		} else if (corrected >= MAX_SYNCHRONISATION_NS) {
954 			++ptp->oversize_sync_windows;
955 		} else if (corrected < ptp->min_synchronisation_ns) {
956 			++ptp->undersize_sync_windows;
957 		} else {
958 			ngood++;
959 			last_good = i;
960 		}
961 	}
962 
963 	if (ngood == 0) {
964 		netif_warn(efx, drv, efx->net_dev,
965 			   "PTP no suitable synchronisations\n");
966 		return -EAGAIN;
967 	}
968 
969 	/* Calculate delay from last good sync (host time) to last_time.
970 	 * It is possible that the seconds rolled over between taking
971 	 * the start reading and the last value written by the host.  The
972 	 * timescales are such that a gap of more than one second is never
973 	 * expected.  delta is *not* normalised.
974 	 */
975 	start_sec = ptp->timeset[last_good].host_start >> MC_NANOSECOND_BITS;
976 	last_sec = last_time->ts_real.tv_sec & MC_SECOND_MASK;
977 	if (start_sec != last_sec &&
978 	    ((start_sec + 1) & MC_SECOND_MASK) != last_sec) {
979 		netif_warn(efx, hw, efx->net_dev,
980 			   "PTP bad synchronisation seconds\n");
981 		return -EAGAIN;
982 	}
983 	delta.tv_sec = (last_sec - start_sec) & 1;
984 	delta.tv_nsec =
985 		last_time->ts_real.tv_nsec -
986 		(ptp->timeset[last_good].host_start & MC_NANOSECOND_MASK);
987 
988 	/* Convert the NIC time at last good sync into kernel time.
989 	 * No correction is required - this time is the output of a
990 	 * firmware process.
991 	 */
992 	mc_time = ptp->nic_to_kernel_time(ptp->timeset[last_good].major,
993 					  ptp->timeset[last_good].minor, 0);
994 
995 	/* Calculate delay from NIC top of second to last_time */
996 	delta.tv_nsec += ktime_to_timespec64(mc_time).tv_nsec;
997 
998 	/* Set PPS timestamp to match NIC top of second */
999 	ptp->host_time_pps = *last_time;
1000 	pps_sub_ts(&ptp->host_time_pps, delta);
1001 
1002 	return 0;
1003 }
1004 
1005 /* Synchronize times between the host and the MC */
efx_ptp_synchronize(struct efx_nic * efx,unsigned int num_readings)1006 static int efx_ptp_synchronize(struct efx_nic *efx, unsigned int num_readings)
1007 {
1008 	struct efx_ptp_data *ptp = efx->ptp_data;
1009 	MCDI_DECLARE_BUF(synch_buf, MC_CMD_PTP_OUT_SYNCHRONIZE_LENMAX);
1010 	size_t response_length;
1011 	int rc;
1012 	unsigned long timeout;
1013 	struct pps_event_time last_time = {};
1014 	unsigned int loops = 0;
1015 	int *start = ptp->start.addr;
1016 
1017 	MCDI_SET_DWORD(synch_buf, PTP_IN_OP, MC_CMD_PTP_OP_SYNCHRONIZE);
1018 	MCDI_SET_DWORD(synch_buf, PTP_IN_PERIPH_ID, 0);
1019 	MCDI_SET_DWORD(synch_buf, PTP_IN_SYNCHRONIZE_NUMTIMESETS,
1020 		       num_readings);
1021 	MCDI_SET_QWORD(synch_buf, PTP_IN_SYNCHRONIZE_START_ADDR,
1022 		       ptp->start.dma_addr);
1023 
1024 	/* Clear flag that signals MC ready */
1025 	WRITE_ONCE(*start, 0);
1026 	rc = efx_mcdi_rpc_start(efx, MC_CMD_PTP, synch_buf,
1027 				MC_CMD_PTP_IN_SYNCHRONIZE_LEN);
1028 	EFX_WARN_ON_ONCE_PARANOID(rc);
1029 
1030 	/* Wait for start from MCDI (or timeout) */
1031 	timeout = jiffies + msecs_to_jiffies(MAX_SYNCHRONISE_WAIT_MS);
1032 	while (!READ_ONCE(*start) && (time_before(jiffies, timeout))) {
1033 		udelay(20);	/* Usually start MCDI execution quickly */
1034 		loops++;
1035 	}
1036 
1037 	if (loops <= 1)
1038 		++ptp->fast_syncs;
1039 	if (!time_before(jiffies, timeout))
1040 		++ptp->sync_timeouts;
1041 
1042 	if (READ_ONCE(*start))
1043 		efx_ptp_send_times(efx, &last_time);
1044 
1045 	/* Collect results */
1046 	rc = efx_mcdi_rpc_finish(efx, MC_CMD_PTP,
1047 				 MC_CMD_PTP_IN_SYNCHRONIZE_LEN,
1048 				 synch_buf, sizeof(synch_buf),
1049 				 &response_length);
1050 	if (rc == 0) {
1051 		rc = efx_ptp_process_times(efx, synch_buf, response_length,
1052 					   &last_time);
1053 		if (rc == 0)
1054 			++ptp->good_syncs;
1055 		else
1056 			++ptp->no_time_syncs;
1057 	}
1058 
1059 	/* Increment the bad syncs counter if the synchronize fails, whatever
1060 	 * the reason.
1061 	 */
1062 	if (rc != 0)
1063 		++ptp->bad_syncs;
1064 
1065 	return rc;
1066 }
1067 
1068 /* Transmit a PTP packet via the dedicated hardware timestamped queue. */
efx_ptp_xmit_skb_queue(struct efx_nic * efx,struct sk_buff * skb)1069 static void efx_ptp_xmit_skb_queue(struct efx_nic *efx, struct sk_buff *skb)
1070 {
1071 	struct efx_ptp_data *ptp_data = efx->ptp_data;
1072 	u8 type = efx_tx_csum_type_skb(skb);
1073 	struct efx_tx_queue *tx_queue;
1074 
1075 	tx_queue = efx_channel_get_tx_queue(ptp_data->channel, type);
1076 	if (tx_queue && tx_queue->timestamping) {
1077 		skb_get(skb);
1078 
1079 		/* This code invokes normal driver TX code which is always
1080 		 * protected from softirqs when called from generic TX code,
1081 		 * which in turn disables preemption. Look at __dev_queue_xmit
1082 		 * which uses rcu_read_lock_bh disabling preemption for RCU
1083 		 * plus disabling softirqs. We do not need RCU reader
1084 		 * protection here.
1085 		 *
1086 		 * Although it is theoretically safe for current PTP TX/RX code
1087 		 * running without disabling softirqs, there are three good
1088 		 * reasond for doing so:
1089 		 *
1090 		 *      1) The code invoked is mainly implemented for non-PTP
1091 		 *         packets and it is always executed with softirqs
1092 		 *         disabled.
1093 		 *      2) This being a single PTP packet, better to not
1094 		 *         interrupt its processing by softirqs which can lead
1095 		 *         to high latencies.
1096 		 *      3) netdev_xmit_more checks preemption is disabled and
1097 		 *         triggers a BUG_ON if not.
1098 		 */
1099 		local_bh_disable();
1100 		efx_enqueue_skb(tx_queue, skb);
1101 		local_bh_enable();
1102 
1103 		/* We need to add the filters after enqueuing the packet.
1104 		 * Otherwise, there's high latency in sending back the
1105 		 * timestamp, causing ptp4l timeouts
1106 		 */
1107 		efx_ptp_insert_unicast_filter(efx, skb);
1108 		dev_consume_skb_any(skb);
1109 	} else {
1110 		WARN_ONCE(1, "PTP channel has no timestamped tx queue\n");
1111 		dev_kfree_skb_any(skb);
1112 	}
1113 }
1114 
1115 /* Transmit a PTP packet, via the MCDI interface, to the wire. */
efx_ptp_xmit_skb_mc(struct efx_nic * efx,struct sk_buff * skb)1116 static void efx_ptp_xmit_skb_mc(struct efx_nic *efx, struct sk_buff *skb)
1117 {
1118 	MCDI_DECLARE_BUF(txtime, MC_CMD_PTP_OUT_TRANSMIT_LEN);
1119 	struct efx_ptp_data *ptp_data = efx->ptp_data;
1120 	struct skb_shared_hwtstamps timestamps;
1121 	size_t len;
1122 	int rc;
1123 
1124 	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_OP, MC_CMD_PTP_OP_TRANSMIT);
1125 	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_PERIPH_ID, 0);
1126 	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_TRANSMIT_LENGTH, skb->len);
1127 	if (skb_shinfo(skb)->nr_frags != 0) {
1128 		rc = skb_linearize(skb);
1129 		if (rc != 0)
1130 			goto fail;
1131 	}
1132 
1133 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
1134 		rc = skb_checksum_help(skb);
1135 		if (rc != 0)
1136 			goto fail;
1137 	}
1138 	skb_copy_from_linear_data(skb,
1139 				  MCDI_PTR(ptp_data->txbuf,
1140 					   PTP_IN_TRANSMIT_PACKET),
1141 				  skb->len);
1142 	rc = efx_mcdi_rpc(efx, MC_CMD_PTP,
1143 			  ptp_data->txbuf, MC_CMD_PTP_IN_TRANSMIT_LEN(skb->len),
1144 			  txtime, sizeof(txtime), &len);
1145 	if (rc != 0)
1146 		goto fail;
1147 
1148 	memset(&timestamps, 0, sizeof(timestamps));
1149 	timestamps.hwtstamp = ptp_data->nic_to_kernel_time(
1150 		MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_MAJOR),
1151 		MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_MINOR),
1152 		ptp_data->ts_corrections.ptp_tx);
1153 
1154 	skb_tstamp_tx(skb, &timestamps);
1155 
1156 	/* Add the filters after sending back the timestamp to avoid delaying it
1157 	 * or ptp4l may timeout.
1158 	 */
1159 	efx_ptp_insert_unicast_filter(efx, skb);
1160 
1161 fail:
1162 	dev_kfree_skb_any(skb);
1163 
1164 	return;
1165 }
1166 
1167 /* Process any queued receive events and corresponding packets
1168  *
1169  * q is returned with all the packets that are ready for delivery.
1170  */
efx_ptp_process_events(struct efx_nic * efx,struct sk_buff_head * q)1171 static void efx_ptp_process_events(struct efx_nic *efx, struct sk_buff_head *q)
1172 {
1173 	struct efx_ptp_data *ptp = efx->ptp_data;
1174 	struct sk_buff *skb;
1175 
1176 	while ((skb = skb_dequeue(&ptp->rxq))) {
1177 		struct efx_ptp_match *match;
1178 
1179 		match = (struct efx_ptp_match *)skb->cb;
1180 		if (match->state == PTP_PACKET_STATE_MATCH_UNWANTED) {
1181 			__skb_queue_tail(q, skb);
1182 		} else if (time_after(jiffies, match->expiry)) {
1183 			match->state = PTP_PACKET_STATE_TIMED_OUT;
1184 			++ptp->rx_no_timestamp;
1185 			__skb_queue_tail(q, skb);
1186 		} else {
1187 			/* Replace unprocessed entry and stop */
1188 			skb_queue_head(&ptp->rxq, skb);
1189 			break;
1190 		}
1191 	}
1192 }
1193 
1194 /* Complete processing of a received packet */
efx_ptp_process_rx(struct efx_nic * efx,struct sk_buff * skb)1195 static inline void efx_ptp_process_rx(struct efx_nic *efx, struct sk_buff *skb)
1196 {
1197 	local_bh_disable();
1198 	netif_receive_skb(skb);
1199 	local_bh_enable();
1200 }
1201 
1202 static struct efx_ptp_rxfilter *
efx_ptp_find_filter(struct list_head * filter_list,struct efx_filter_spec * spec)1203 efx_ptp_find_filter(struct list_head *filter_list, struct efx_filter_spec *spec)
1204 {
1205 	struct efx_ptp_rxfilter *rxfilter;
1206 
1207 	list_for_each_entry(rxfilter, filter_list, list) {
1208 		if (rxfilter->ether_type == spec->ether_type &&
1209 		    rxfilter->loc_port == spec->loc_port &&
1210 		    !memcmp(rxfilter->loc_host, spec->loc_host, sizeof(spec->loc_host)))
1211 			return rxfilter;
1212 	}
1213 
1214 	return NULL;
1215 }
1216 
efx_ptp_remove_one_filter(struct efx_nic * efx,struct efx_ptp_rxfilter * rxfilter)1217 static void efx_ptp_remove_one_filter(struct efx_nic *efx,
1218 				      struct efx_ptp_rxfilter *rxfilter)
1219 {
1220 	efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED,
1221 				  rxfilter->handle);
1222 	list_del(&rxfilter->list);
1223 	kfree(rxfilter);
1224 }
1225 
efx_ptp_remove_filters(struct efx_nic * efx,struct list_head * filter_list)1226 static void efx_ptp_remove_filters(struct efx_nic *efx,
1227 				   struct list_head *filter_list)
1228 {
1229 	struct efx_ptp_rxfilter *rxfilter, *tmp;
1230 
1231 	list_for_each_entry_safe(rxfilter, tmp, filter_list, list)
1232 		efx_ptp_remove_one_filter(efx, rxfilter);
1233 }
1234 
efx_ptp_init_filter(struct efx_nic * efx,struct efx_filter_spec * rxfilter)1235 static void efx_ptp_init_filter(struct efx_nic *efx,
1236 				struct efx_filter_spec *rxfilter)
1237 {
1238 	struct efx_channel *channel = efx->ptp_data->channel;
1239 	struct efx_rx_queue *queue = efx_channel_get_rx_queue(channel);
1240 
1241 	efx_filter_init_rx(rxfilter, EFX_FILTER_PRI_REQUIRED, 0,
1242 			   efx_rx_queue_index(queue));
1243 }
1244 
efx_ptp_insert_filter(struct efx_nic * efx,struct list_head * filter_list,struct efx_filter_spec * spec,unsigned long expiry)1245 static int efx_ptp_insert_filter(struct efx_nic *efx,
1246 				 struct list_head *filter_list,
1247 				 struct efx_filter_spec *spec,
1248 				 unsigned long expiry)
1249 {
1250 	struct efx_ptp_data *ptp = efx->ptp_data;
1251 	struct efx_ptp_rxfilter *rxfilter;
1252 	int rc;
1253 
1254 	rxfilter = efx_ptp_find_filter(filter_list, spec);
1255 	if (rxfilter) {
1256 		rxfilter->expiry = expiry;
1257 		return 0;
1258 	}
1259 
1260 	rxfilter = kzalloc(sizeof(*rxfilter), GFP_KERNEL);
1261 	if (!rxfilter)
1262 		return -ENOMEM;
1263 
1264 	rc = efx_filter_insert_filter(efx, spec, true);
1265 	if (rc < 0)
1266 		goto fail;
1267 
1268 	rxfilter->handle = rc;
1269 	rxfilter->ether_type = spec->ether_type;
1270 	rxfilter->loc_port = spec->loc_port;
1271 	memcpy(rxfilter->loc_host, spec->loc_host, sizeof(spec->loc_host));
1272 	rxfilter->expiry = expiry;
1273 	list_add(&rxfilter->list, filter_list);
1274 
1275 	queue_delayed_work(ptp->workwq, &ptp->cleanup_work,
1276 			   UCAST_FILTER_EXPIRY_JIFFIES + 1);
1277 
1278 	return 0;
1279 
1280 fail:
1281 	kfree(rxfilter);
1282 	return rc;
1283 }
1284 
efx_ptp_insert_ipv4_filter(struct efx_nic * efx,struct list_head * filter_list,__be32 addr,u16 port,unsigned long expiry)1285 static int efx_ptp_insert_ipv4_filter(struct efx_nic *efx,
1286 				      struct list_head *filter_list,
1287 				      __be32 addr, u16 port,
1288 				      unsigned long expiry)
1289 {
1290 	struct efx_filter_spec spec;
1291 
1292 	efx_ptp_init_filter(efx, &spec);
1293 	efx_filter_set_ipv4_local(&spec, IPPROTO_UDP, addr, htons(port));
1294 	return efx_ptp_insert_filter(efx, filter_list, &spec, expiry);
1295 }
1296 
efx_ptp_insert_ipv6_filter(struct efx_nic * efx,struct list_head * filter_list,struct in6_addr * addr,u16 port,unsigned long expiry)1297 static int efx_ptp_insert_ipv6_filter(struct efx_nic *efx,
1298 				      struct list_head *filter_list,
1299 				      struct in6_addr *addr, u16 port,
1300 				      unsigned long expiry)
1301 {
1302 	struct efx_filter_spec spec;
1303 
1304 	efx_ptp_init_filter(efx, &spec);
1305 	efx_filter_set_ipv6_local(&spec, IPPROTO_UDP, addr, htons(port));
1306 	return efx_ptp_insert_filter(efx, filter_list, &spec, expiry);
1307 }
1308 
efx_ptp_insert_eth_multicast_filter(struct efx_nic * efx)1309 static int efx_ptp_insert_eth_multicast_filter(struct efx_nic *efx)
1310 {
1311 	struct efx_ptp_data *ptp = efx->ptp_data;
1312 	const u8 addr[ETH_ALEN] = PTP_ADDR_ETHER;
1313 	struct efx_filter_spec spec;
1314 
1315 	efx_ptp_init_filter(efx, &spec);
1316 	efx_filter_set_eth_local(&spec, EFX_FILTER_VID_UNSPEC, addr);
1317 	spec.match_flags |= EFX_FILTER_MATCH_ETHER_TYPE;
1318 	spec.ether_type = htons(ETH_P_1588);
1319 	return efx_ptp_insert_filter(efx, &ptp->rxfilters_mcast, &spec, 0);
1320 }
1321 
efx_ptp_insert_multicast_filters(struct efx_nic * efx)1322 static int efx_ptp_insert_multicast_filters(struct efx_nic *efx)
1323 {
1324 	struct efx_ptp_data *ptp = efx->ptp_data;
1325 	int rc;
1326 
1327 	if (!ptp->channel || !list_empty(&ptp->rxfilters_mcast))
1328 		return 0;
1329 
1330 	/* Must filter on both event and general ports to ensure
1331 	 * that there is no packet re-ordering.
1332 	 */
1333 	rc = efx_ptp_insert_ipv4_filter(efx, &ptp->rxfilters_mcast,
1334 					htonl(PTP_ADDR_IPV4), PTP_EVENT_PORT,
1335 					0);
1336 	if (rc < 0)
1337 		goto fail;
1338 
1339 	rc = efx_ptp_insert_ipv4_filter(efx, &ptp->rxfilters_mcast,
1340 					htonl(PTP_ADDR_IPV4), PTP_GENERAL_PORT,
1341 					0);
1342 	if (rc < 0)
1343 		goto fail;
1344 
1345 	/* if the NIC supports hw timestamps by the MAC, we can support
1346 	 * PTP over IPv6 and Ethernet
1347 	 */
1348 	if (efx_ptp_use_mac_tx_timestamps(efx)) {
1349 		struct in6_addr ipv6_addr = {{PTP_ADDR_IPV6}};
1350 
1351 		rc = efx_ptp_insert_ipv6_filter(efx, &ptp->rxfilters_mcast,
1352 						&ipv6_addr, PTP_EVENT_PORT, 0);
1353 		if (rc < 0)
1354 			goto fail;
1355 
1356 		rc = efx_ptp_insert_ipv6_filter(efx, &ptp->rxfilters_mcast,
1357 						&ipv6_addr, PTP_GENERAL_PORT, 0);
1358 		if (rc < 0)
1359 			goto fail;
1360 
1361 		rc = efx_ptp_insert_eth_multicast_filter(efx);
1362 
1363 		/* Not all firmware variants support this filter */
1364 		if (rc < 0 && rc != -EPROTONOSUPPORT)
1365 			goto fail;
1366 	}
1367 
1368 	return 0;
1369 
1370 fail:
1371 	efx_ptp_remove_filters(efx, &ptp->rxfilters_mcast);
1372 	return rc;
1373 }
1374 
efx_ptp_valid_unicast_event_pkt(struct sk_buff * skb)1375 static bool efx_ptp_valid_unicast_event_pkt(struct sk_buff *skb)
1376 {
1377 	if (skb->protocol == htons(ETH_P_IP)) {
1378 		return ip_hdr(skb)->daddr != htonl(PTP_ADDR_IPV4) &&
1379 			ip_hdr(skb)->protocol == IPPROTO_UDP &&
1380 			udp_hdr(skb)->source == htons(PTP_EVENT_PORT);
1381 	} else if (skb->protocol == htons(ETH_P_IPV6)) {
1382 		struct in6_addr mcast_addr = {{PTP_ADDR_IPV6}};
1383 
1384 		return !ipv6_addr_equal(&ipv6_hdr(skb)->daddr, &mcast_addr) &&
1385 			ipv6_hdr(skb)->nexthdr == IPPROTO_UDP &&
1386 			udp_hdr(skb)->source == htons(PTP_EVENT_PORT);
1387 	}
1388 	return false;
1389 }
1390 
efx_ptp_insert_unicast_filter(struct efx_nic * efx,struct sk_buff * skb)1391 static int efx_ptp_insert_unicast_filter(struct efx_nic *efx,
1392 					 struct sk_buff *skb)
1393 {
1394 	struct efx_ptp_data *ptp = efx->ptp_data;
1395 	unsigned long expiry;
1396 	int rc;
1397 
1398 	if (!efx_ptp_valid_unicast_event_pkt(skb))
1399 		return -EINVAL;
1400 
1401 	expiry = jiffies + UCAST_FILTER_EXPIRY_JIFFIES;
1402 
1403 	if (skb->protocol == htons(ETH_P_IP)) {
1404 		__be32 addr = ip_hdr(skb)->saddr;
1405 
1406 		rc = efx_ptp_insert_ipv4_filter(efx, &ptp->rxfilters_ucast,
1407 						addr, PTP_EVENT_PORT, expiry);
1408 		if (rc < 0)
1409 			goto out;
1410 
1411 		rc = efx_ptp_insert_ipv4_filter(efx, &ptp->rxfilters_ucast,
1412 						addr, PTP_GENERAL_PORT, expiry);
1413 	} else if (efx_ptp_use_mac_tx_timestamps(efx)) {
1414 		/* IPv6 PTP only supported by devices with MAC hw timestamp */
1415 		struct in6_addr *addr = &ipv6_hdr(skb)->saddr;
1416 
1417 		rc = efx_ptp_insert_ipv6_filter(efx, &ptp->rxfilters_ucast,
1418 						addr, PTP_EVENT_PORT, expiry);
1419 		if (rc < 0)
1420 			goto out;
1421 
1422 		rc = efx_ptp_insert_ipv6_filter(efx, &ptp->rxfilters_ucast,
1423 						addr, PTP_GENERAL_PORT, expiry);
1424 	} else {
1425 		return -EOPNOTSUPP;
1426 	}
1427 
1428 out:
1429 	return rc;
1430 }
1431 
efx_ptp_start(struct efx_nic * efx)1432 static int efx_ptp_start(struct efx_nic *efx)
1433 {
1434 	struct efx_ptp_data *ptp = efx->ptp_data;
1435 	int rc;
1436 
1437 	ptp->reset_required = false;
1438 
1439 	rc = efx_ptp_insert_multicast_filters(efx);
1440 	if (rc)
1441 		return rc;
1442 
1443 	rc = efx_ptp_enable(efx);
1444 	if (rc != 0)
1445 		goto fail;
1446 
1447 	ptp->evt_frag_idx = 0;
1448 	ptp->current_adjfreq = 0;
1449 
1450 	return 0;
1451 
1452 fail:
1453 	efx_ptp_remove_filters(efx, &ptp->rxfilters_mcast);
1454 	return rc;
1455 }
1456 
efx_ptp_stop(struct efx_nic * efx)1457 static int efx_ptp_stop(struct efx_nic *efx)
1458 {
1459 	struct efx_ptp_data *ptp = efx->ptp_data;
1460 	int rc;
1461 
1462 	if (ptp == NULL)
1463 		return 0;
1464 
1465 	rc = efx_ptp_disable(efx);
1466 
1467 	efx_ptp_remove_filters(efx, &ptp->rxfilters_mcast);
1468 	efx_ptp_remove_filters(efx, &ptp->rxfilters_ucast);
1469 
1470 	/* Make sure RX packets are really delivered */
1471 	efx_ptp_deliver_rx_queue(&efx->ptp_data->rxq);
1472 	skb_queue_purge(&efx->ptp_data->txq);
1473 
1474 	return rc;
1475 }
1476 
efx_ptp_restart(struct efx_nic * efx)1477 static int efx_ptp_restart(struct efx_nic *efx)
1478 {
1479 	if (efx->ptp_data && efx->ptp_data->enabled)
1480 		return efx_ptp_start(efx);
1481 	return 0;
1482 }
1483 
efx_ptp_pps_worker(struct work_struct * work)1484 static void efx_ptp_pps_worker(struct work_struct *work)
1485 {
1486 	struct efx_ptp_data *ptp =
1487 		container_of(work, struct efx_ptp_data, pps_work);
1488 	struct efx_nic *efx = ptp->efx;
1489 	struct ptp_clock_event ptp_evt;
1490 
1491 	if (efx_ptp_synchronize(efx, PTP_SYNC_ATTEMPTS))
1492 		return;
1493 
1494 	ptp_evt.type = PTP_CLOCK_PPSUSR;
1495 	ptp_evt.pps_times = ptp->host_time_pps;
1496 	ptp_clock_event(ptp->phc_clock, &ptp_evt);
1497 }
1498 
efx_ptp_worker(struct work_struct * work)1499 static void efx_ptp_worker(struct work_struct *work)
1500 {
1501 	struct efx_ptp_data *ptp_data =
1502 		container_of(work, struct efx_ptp_data, work);
1503 	struct efx_nic *efx = ptp_data->efx;
1504 	struct sk_buff *skb;
1505 	struct sk_buff_head tempq;
1506 
1507 	if (ptp_data->reset_required) {
1508 		efx_ptp_stop(efx);
1509 		efx_ptp_start(efx);
1510 		return;
1511 	}
1512 
1513 	__skb_queue_head_init(&tempq);
1514 	efx_ptp_process_events(efx, &tempq);
1515 
1516 	while ((skb = skb_dequeue(&ptp_data->txq)))
1517 		ptp_data->xmit_skb(efx, skb);
1518 
1519 	while ((skb = __skb_dequeue(&tempq)))
1520 		efx_ptp_process_rx(efx, skb);
1521 }
1522 
efx_ptp_cleanup_worker(struct work_struct * work)1523 static void efx_ptp_cleanup_worker(struct work_struct *work)
1524 {
1525 	struct efx_ptp_data *ptp =
1526 		container_of(work, struct efx_ptp_data, cleanup_work.work);
1527 	struct efx_ptp_rxfilter *rxfilter, *tmp;
1528 
1529 	list_for_each_entry_safe(rxfilter, tmp, &ptp->rxfilters_ucast, list) {
1530 		if (time_is_before_jiffies(rxfilter->expiry))
1531 			efx_ptp_remove_one_filter(ptp->efx, rxfilter);
1532 	}
1533 
1534 	if (!list_empty(&ptp->rxfilters_ucast)) {
1535 		queue_delayed_work(ptp->workwq, &ptp->cleanup_work,
1536 				   UCAST_FILTER_EXPIRY_JIFFIES + 1);
1537 	}
1538 }
1539 
1540 static const struct ptp_clock_info efx_phc_clock_info = {
1541 	.owner		= THIS_MODULE,
1542 	.name		= "sfc",
1543 	.max_adj	= MAX_PPB,
1544 	.n_alarm	= 0,
1545 	.n_ext_ts	= 0,
1546 	.n_per_out	= 0,
1547 	.n_pins		= 0,
1548 	.pps		= 1,
1549 	.adjfine	= efx_phc_adjfine,
1550 	.adjtime	= efx_phc_adjtime,
1551 	.gettime64	= efx_phc_gettime,
1552 	.settime64	= efx_phc_settime,
1553 	.enable		= efx_phc_enable,
1554 };
1555 
1556 /* Initialise PTP state. */
efx_ptp_probe(struct efx_nic * efx,struct efx_channel * channel)1557 int efx_ptp_probe(struct efx_nic *efx, struct efx_channel *channel)
1558 {
1559 	struct efx_ptp_data *ptp;
1560 	int rc = 0;
1561 
1562 	if (efx->ptp_data) {
1563 		efx->ptp_data->channel = channel;
1564 		return 0;
1565 	}
1566 
1567 	ptp = kzalloc(sizeof(struct efx_ptp_data), GFP_KERNEL);
1568 	efx->ptp_data = ptp;
1569 	if (!efx->ptp_data)
1570 		return -ENOMEM;
1571 
1572 	ptp->efx = efx;
1573 	ptp->channel = channel;
1574 
1575 	rc = efx_nic_alloc_buffer(efx, &ptp->start, sizeof(int), GFP_KERNEL);
1576 	if (rc != 0)
1577 		goto fail1;
1578 
1579 	skb_queue_head_init(&ptp->rxq);
1580 	skb_queue_head_init(&ptp->txq);
1581 	ptp->workwq = create_singlethread_workqueue("sfc_ptp");
1582 	if (!ptp->workwq) {
1583 		rc = -ENOMEM;
1584 		goto fail2;
1585 	}
1586 
1587 	if (efx_ptp_use_mac_tx_timestamps(efx)) {
1588 		ptp->xmit_skb = efx_ptp_xmit_skb_queue;
1589 		/* Request sync events on this channel. */
1590 		channel->sync_events_state = SYNC_EVENTS_QUIESCENT;
1591 	} else {
1592 		ptp->xmit_skb = efx_ptp_xmit_skb_mc;
1593 	}
1594 
1595 	INIT_WORK(&ptp->work, efx_ptp_worker);
1596 	INIT_DELAYED_WORK(&ptp->cleanup_work, efx_ptp_cleanup_worker);
1597 	ptp->config.flags = 0;
1598 	ptp->config.tx_type = HWTSTAMP_TX_OFF;
1599 	ptp->config.rx_filter = HWTSTAMP_FILTER_NONE;
1600 	INIT_LIST_HEAD(&ptp->rxfilters_mcast);
1601 	INIT_LIST_HEAD(&ptp->rxfilters_ucast);
1602 
1603 	/* Get the NIC PTP attributes and set up time conversions */
1604 	rc = efx_ptp_get_attributes(efx);
1605 	if (rc < 0)
1606 		goto fail3;
1607 
1608 	/* Get the timestamp corrections */
1609 	rc = efx_ptp_get_timestamp_corrections(efx);
1610 	if (rc < 0)
1611 		goto fail3;
1612 
1613 	if (efx->mcdi->fn_flags &
1614 	    (1 << MC_CMD_DRV_ATTACH_EXT_OUT_FLAG_PRIMARY)) {
1615 		ptp->phc_clock_info = efx_phc_clock_info;
1616 		ptp->phc_clock = ptp_clock_register(&ptp->phc_clock_info,
1617 						    &efx->pci_dev->dev);
1618 		if (IS_ERR(ptp->phc_clock)) {
1619 			rc = PTR_ERR(ptp->phc_clock);
1620 			goto fail3;
1621 		} else if (ptp->phc_clock) {
1622 			INIT_WORK(&ptp->pps_work, efx_ptp_pps_worker);
1623 			ptp->pps_workwq = create_singlethread_workqueue("sfc_pps");
1624 			if (!ptp->pps_workwq) {
1625 				rc = -ENOMEM;
1626 				goto fail4;
1627 			}
1628 		}
1629 	}
1630 	ptp->nic_ts_enabled = false;
1631 
1632 	return 0;
1633 fail4:
1634 	ptp_clock_unregister(efx->ptp_data->phc_clock);
1635 
1636 fail3:
1637 	destroy_workqueue(efx->ptp_data->workwq);
1638 
1639 fail2:
1640 	efx_nic_free_buffer(efx, &ptp->start);
1641 
1642 fail1:
1643 	kfree(efx->ptp_data);
1644 	efx->ptp_data = NULL;
1645 
1646 	return rc;
1647 }
1648 
1649 /* Initialise PTP channel.
1650  *
1651  * Setting core_index to zero causes the queue to be initialised and doesn't
1652  * overlap with 'rxq0' because ptp.c doesn't use skb_record_rx_queue.
1653  */
efx_ptp_probe_channel(struct efx_channel * channel)1654 static int efx_ptp_probe_channel(struct efx_channel *channel)
1655 {
1656 	struct efx_nic *efx = channel->efx;
1657 	int rc;
1658 
1659 	channel->irq_moderation_us = 0;
1660 	channel->rx_queue.core_index = 0;
1661 
1662 	rc = efx_ptp_probe(efx, channel);
1663 	/* Failure to probe PTP is not fatal; this channel will just not be
1664 	 * used for anything.
1665 	 * In the case of EPERM, efx_ptp_probe will print its own message (in
1666 	 * efx_ptp_get_attributes()), so we don't need to.
1667 	 */
1668 	if (rc && rc != -EPERM)
1669 		netif_warn(efx, drv, efx->net_dev,
1670 			   "Failed to probe PTP, rc=%d\n", rc);
1671 	return 0;
1672 }
1673 
efx_ptp_remove(struct efx_nic * efx)1674 void efx_ptp_remove(struct efx_nic *efx)
1675 {
1676 	if (!efx->ptp_data)
1677 		return;
1678 
1679 	(void)efx_ptp_disable(efx);
1680 
1681 	cancel_work_sync(&efx->ptp_data->work);
1682 	cancel_delayed_work_sync(&efx->ptp_data->cleanup_work);
1683 	if (efx->ptp_data->pps_workwq)
1684 		cancel_work_sync(&efx->ptp_data->pps_work);
1685 
1686 	skb_queue_purge(&efx->ptp_data->rxq);
1687 	skb_queue_purge(&efx->ptp_data->txq);
1688 
1689 	if (efx->ptp_data->phc_clock) {
1690 		destroy_workqueue(efx->ptp_data->pps_workwq);
1691 		ptp_clock_unregister(efx->ptp_data->phc_clock);
1692 	}
1693 
1694 	destroy_workqueue(efx->ptp_data->workwq);
1695 
1696 	efx_nic_free_buffer(efx, &efx->ptp_data->start);
1697 	kfree(efx->ptp_data);
1698 	efx->ptp_data = NULL;
1699 }
1700 
efx_ptp_remove_channel(struct efx_channel * channel)1701 static void efx_ptp_remove_channel(struct efx_channel *channel)
1702 {
1703 	efx_ptp_remove(channel->efx);
1704 }
1705 
efx_ptp_get_channel_name(struct efx_channel * channel,char * buf,size_t len)1706 static void efx_ptp_get_channel_name(struct efx_channel *channel,
1707 				     char *buf, size_t len)
1708 {
1709 	snprintf(buf, len, "%s-ptp", channel->efx->name);
1710 }
1711 
1712 /* Determine whether this packet should be processed by the PTP module
1713  * or transmitted conventionally.
1714  */
efx_ptp_is_ptp_tx(struct efx_nic * efx,struct sk_buff * skb)1715 bool efx_ptp_is_ptp_tx(struct efx_nic *efx, struct sk_buff *skb)
1716 {
1717 	return efx->ptp_data &&
1718 		efx->ptp_data->enabled &&
1719 		skb->len >= PTP_MIN_LENGTH &&
1720 		skb->len <= MC_CMD_PTP_IN_TRANSMIT_PACKET_MAXNUM &&
1721 		likely(skb->protocol == htons(ETH_P_IP)) &&
1722 		skb_transport_header_was_set(skb) &&
1723 		skb_network_header_len(skb) >= sizeof(struct iphdr) &&
1724 		ip_hdr(skb)->protocol == IPPROTO_UDP &&
1725 		skb_headlen(skb) >=
1726 		skb_transport_offset(skb) + sizeof(struct udphdr) &&
1727 		udp_hdr(skb)->dest == htons(PTP_EVENT_PORT);
1728 }
1729 
1730 /* Receive a PTP packet.  Packets are queued until the arrival of
1731  * the receive timestamp from the MC - this will probably occur after the
1732  * packet arrival because of the processing in the MC.
1733  */
efx_ptp_rx(struct efx_channel * channel,struct sk_buff * skb)1734 static bool efx_ptp_rx(struct efx_channel *channel, struct sk_buff *skb)
1735 {
1736 	struct efx_nic *efx = channel->efx;
1737 	struct efx_ptp_data *ptp = efx->ptp_data;
1738 	struct efx_ptp_match *match = (struct efx_ptp_match *)skb->cb;
1739 	unsigned int version;
1740 	u8 *data;
1741 
1742 	match->expiry = jiffies + msecs_to_jiffies(PKT_EVENT_LIFETIME_MS);
1743 
1744 	/* Correct version? */
1745 	if (ptp->mode == MC_CMD_PTP_MODE_V1) {
1746 		if (!pskb_may_pull(skb, PTP_V1_MIN_LENGTH)) {
1747 			return false;
1748 		}
1749 		data = skb->data;
1750 		version = ntohs(*(__be16 *)&data[PTP_V1_VERSION_OFFSET]);
1751 		if (version != PTP_VERSION_V1) {
1752 			return false;
1753 		}
1754 	} else {
1755 		if (!pskb_may_pull(skb, PTP_V2_MIN_LENGTH)) {
1756 			return false;
1757 		}
1758 		data = skb->data;
1759 		version = data[PTP_V2_VERSION_OFFSET];
1760 		if ((version & PTP_VERSION_V2_MASK) != PTP_VERSION_V2) {
1761 			return false;
1762 		}
1763 	}
1764 
1765 	/* Does this packet require timestamping? */
1766 	if (ntohs(*(__be16 *)&data[PTP_DPORT_OFFSET]) == PTP_EVENT_PORT) {
1767 		match->state = PTP_PACKET_STATE_UNMATCHED;
1768 
1769 		/* We expect the sequence number to be in the same position in
1770 		 * the packet for PTP V1 and V2
1771 		 */
1772 		BUILD_BUG_ON(PTP_V1_SEQUENCE_OFFSET != PTP_V2_SEQUENCE_OFFSET);
1773 		BUILD_BUG_ON(PTP_V1_SEQUENCE_LENGTH != PTP_V2_SEQUENCE_LENGTH);
1774 	} else {
1775 		match->state = PTP_PACKET_STATE_MATCH_UNWANTED;
1776 	}
1777 
1778 	skb_queue_tail(&ptp->rxq, skb);
1779 	queue_work(ptp->workwq, &ptp->work);
1780 
1781 	return true;
1782 }
1783 
1784 /* Transmit a PTP packet.  This has to be transmitted by the MC
1785  * itself, through an MCDI call.  MCDI calls aren't permitted
1786  * in the transmit path so defer the actual transmission to a suitable worker.
1787  */
efx_ptp_tx(struct efx_nic * efx,struct sk_buff * skb)1788 int efx_ptp_tx(struct efx_nic *efx, struct sk_buff *skb)
1789 {
1790 	struct efx_ptp_data *ptp = efx->ptp_data;
1791 
1792 	skb_queue_tail(&ptp->txq, skb);
1793 
1794 	if ((udp_hdr(skb)->dest == htons(PTP_EVENT_PORT)) &&
1795 	    (skb->len <= MC_CMD_PTP_IN_TRANSMIT_PACKET_MAXNUM))
1796 		efx_xmit_hwtstamp_pending(skb);
1797 	queue_work(ptp->workwq, &ptp->work);
1798 
1799 	return NETDEV_TX_OK;
1800 }
1801 
efx_ptp_get_mode(struct efx_nic * efx)1802 int efx_ptp_get_mode(struct efx_nic *efx)
1803 {
1804 	return efx->ptp_data->mode;
1805 }
1806 
efx_ptp_change_mode(struct efx_nic * efx,bool enable_wanted,unsigned int new_mode)1807 int efx_ptp_change_mode(struct efx_nic *efx, bool enable_wanted,
1808 			unsigned int new_mode)
1809 {
1810 	if ((enable_wanted != efx->ptp_data->enabled) ||
1811 	    (enable_wanted && (efx->ptp_data->mode != new_mode))) {
1812 		int rc = 0;
1813 
1814 		if (enable_wanted) {
1815 			/* Change of mode requires disable */
1816 			if (efx->ptp_data->enabled &&
1817 			    (efx->ptp_data->mode != new_mode)) {
1818 				efx->ptp_data->enabled = false;
1819 				rc = efx_ptp_stop(efx);
1820 				if (rc != 0)
1821 					return rc;
1822 			}
1823 
1824 			/* Set new operating mode and establish
1825 			 * baseline synchronisation, which must
1826 			 * succeed.
1827 			 */
1828 			efx->ptp_data->mode = new_mode;
1829 			if (netif_running(efx->net_dev))
1830 				rc = efx_ptp_start(efx);
1831 			if (rc == 0) {
1832 				rc = efx_ptp_synchronize(efx,
1833 							 PTP_SYNC_ATTEMPTS * 2);
1834 				if (rc != 0)
1835 					efx_ptp_stop(efx);
1836 			}
1837 		} else {
1838 			rc = efx_ptp_stop(efx);
1839 		}
1840 
1841 		if (rc != 0)
1842 			return rc;
1843 
1844 		efx->ptp_data->enabled = enable_wanted;
1845 	}
1846 
1847 	return 0;
1848 }
1849 
efx_ptp_ts_init(struct efx_nic * efx,struct hwtstamp_config * init)1850 static int efx_ptp_ts_init(struct efx_nic *efx, struct hwtstamp_config *init)
1851 {
1852 	int rc;
1853 
1854 	if ((init->tx_type != HWTSTAMP_TX_OFF) &&
1855 	    (init->tx_type != HWTSTAMP_TX_ON))
1856 		return -ERANGE;
1857 
1858 	rc = efx->type->ptp_set_ts_config(efx, init);
1859 	if (rc)
1860 		return rc;
1861 
1862 	efx->ptp_data->config = *init;
1863 	return 0;
1864 }
1865 
efx_ptp_get_ts_info(struct efx_nic * efx,struct ethtool_ts_info * ts_info)1866 void efx_ptp_get_ts_info(struct efx_nic *efx, struct ethtool_ts_info *ts_info)
1867 {
1868 	struct efx_ptp_data *ptp = efx->ptp_data;
1869 	struct efx_nic *primary = efx->primary;
1870 
1871 	ASSERT_RTNL();
1872 
1873 	if (!ptp)
1874 		return;
1875 
1876 	ts_info->so_timestamping |= (SOF_TIMESTAMPING_TX_HARDWARE |
1877 				     SOF_TIMESTAMPING_RX_HARDWARE |
1878 				     SOF_TIMESTAMPING_RAW_HARDWARE);
1879 	/* Check licensed features.  If we don't have the license for TX
1880 	 * timestamps, the NIC will not support them.
1881 	 */
1882 	if (efx_ptp_use_mac_tx_timestamps(efx)) {
1883 		struct efx_ef10_nic_data *nic_data = efx->nic_data;
1884 
1885 		if (!(nic_data->licensed_features &
1886 		      (1 << LICENSED_V3_FEATURES_TX_TIMESTAMPS_LBN)))
1887 			ts_info->so_timestamping &=
1888 				~SOF_TIMESTAMPING_TX_HARDWARE;
1889 	}
1890 	if (primary && primary->ptp_data && primary->ptp_data->phc_clock)
1891 		ts_info->phc_index =
1892 			ptp_clock_index(primary->ptp_data->phc_clock);
1893 	ts_info->tx_types = 1 << HWTSTAMP_TX_OFF | 1 << HWTSTAMP_TX_ON;
1894 	ts_info->rx_filters = ptp->efx->type->hwtstamp_filters;
1895 }
1896 
efx_ptp_set_ts_config(struct efx_nic * efx,struct ifreq * ifr)1897 int efx_ptp_set_ts_config(struct efx_nic *efx, struct ifreq *ifr)
1898 {
1899 	struct hwtstamp_config config;
1900 	int rc;
1901 
1902 	/* Not a PTP enabled port */
1903 	if (!efx->ptp_data)
1904 		return -EOPNOTSUPP;
1905 
1906 	if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
1907 		return -EFAULT;
1908 
1909 	rc = efx_ptp_ts_init(efx, &config);
1910 	if (rc != 0)
1911 		return rc;
1912 
1913 	return copy_to_user(ifr->ifr_data, &config, sizeof(config))
1914 		? -EFAULT : 0;
1915 }
1916 
efx_ptp_get_ts_config(struct efx_nic * efx,struct ifreq * ifr)1917 int efx_ptp_get_ts_config(struct efx_nic *efx, struct ifreq *ifr)
1918 {
1919 	if (!efx->ptp_data)
1920 		return -EOPNOTSUPP;
1921 
1922 	return copy_to_user(ifr->ifr_data, &efx->ptp_data->config,
1923 			    sizeof(efx->ptp_data->config)) ? -EFAULT : 0;
1924 }
1925 
ptp_event_failure(struct efx_nic * efx,int expected_frag_len)1926 static void ptp_event_failure(struct efx_nic *efx, int expected_frag_len)
1927 {
1928 	struct efx_ptp_data *ptp = efx->ptp_data;
1929 
1930 	netif_err(efx, hw, efx->net_dev,
1931 		"PTP unexpected event length: got %d expected %d\n",
1932 		ptp->evt_frag_idx, expected_frag_len);
1933 	ptp->reset_required = true;
1934 	queue_work(ptp->workwq, &ptp->work);
1935 }
1936 
ptp_event_fault(struct efx_nic * efx,struct efx_ptp_data * ptp)1937 static void ptp_event_fault(struct efx_nic *efx, struct efx_ptp_data *ptp)
1938 {
1939 	int code = EFX_QWORD_FIELD(ptp->evt_frags[0], MCDI_EVENT_DATA);
1940 	if (ptp->evt_frag_idx != 1) {
1941 		ptp_event_failure(efx, 1);
1942 		return;
1943 	}
1944 
1945 	netif_err(efx, hw, efx->net_dev, "PTP error %d\n", code);
1946 }
1947 
ptp_event_pps(struct efx_nic * efx,struct efx_ptp_data * ptp)1948 static void ptp_event_pps(struct efx_nic *efx, struct efx_ptp_data *ptp)
1949 {
1950 	if (ptp->nic_ts_enabled)
1951 		queue_work(ptp->pps_workwq, &ptp->pps_work);
1952 }
1953 
efx_ptp_event(struct efx_nic * efx,efx_qword_t * ev)1954 void efx_ptp_event(struct efx_nic *efx, efx_qword_t *ev)
1955 {
1956 	struct efx_ptp_data *ptp = efx->ptp_data;
1957 	int code = EFX_QWORD_FIELD(*ev, MCDI_EVENT_CODE);
1958 
1959 	if (!ptp) {
1960 		if (!efx->ptp_warned) {
1961 			netif_warn(efx, drv, efx->net_dev,
1962 				   "Received PTP event but PTP not set up\n");
1963 			efx->ptp_warned = true;
1964 		}
1965 		return;
1966 	}
1967 
1968 	if (!ptp->enabled)
1969 		return;
1970 
1971 	if (ptp->evt_frag_idx == 0) {
1972 		ptp->evt_code = code;
1973 	} else if (ptp->evt_code != code) {
1974 		netif_err(efx, hw, efx->net_dev,
1975 			  "PTP out of sequence event %d\n", code);
1976 		ptp->evt_frag_idx = 0;
1977 	}
1978 
1979 	ptp->evt_frags[ptp->evt_frag_idx++] = *ev;
1980 	if (!MCDI_EVENT_FIELD(*ev, CONT)) {
1981 		/* Process resulting event */
1982 		switch (code) {
1983 		case MCDI_EVENT_CODE_PTP_FAULT:
1984 			ptp_event_fault(efx, ptp);
1985 			break;
1986 		case MCDI_EVENT_CODE_PTP_PPS:
1987 			ptp_event_pps(efx, ptp);
1988 			break;
1989 		default:
1990 			netif_err(efx, hw, efx->net_dev,
1991 				  "PTP unknown event %d\n", code);
1992 			break;
1993 		}
1994 		ptp->evt_frag_idx = 0;
1995 	} else if (MAX_EVENT_FRAGS == ptp->evt_frag_idx) {
1996 		netif_err(efx, hw, efx->net_dev,
1997 			  "PTP too many event fragments\n");
1998 		ptp->evt_frag_idx = 0;
1999 	}
2000 }
2001 
efx_time_sync_event(struct efx_channel * channel,efx_qword_t * ev)2002 void efx_time_sync_event(struct efx_channel *channel, efx_qword_t *ev)
2003 {
2004 	struct efx_nic *efx = channel->efx;
2005 	struct efx_ptp_data *ptp = efx->ptp_data;
2006 
2007 	/* When extracting the sync timestamp minor value, we should discard
2008 	 * the least significant two bits. These are not required in order
2009 	 * to reconstruct full-range timestamps and they are optionally used
2010 	 * to report status depending on the options supplied when subscribing
2011 	 * for sync events.
2012 	 */
2013 	channel->sync_timestamp_major = MCDI_EVENT_FIELD(*ev, PTP_TIME_MAJOR);
2014 	channel->sync_timestamp_minor =
2015 		(MCDI_EVENT_FIELD(*ev, PTP_TIME_MINOR_MS_8BITS) & 0xFC)
2016 			<< ptp->nic_time.sync_event_minor_shift;
2017 
2018 	/* if sync events have been disabled then we want to silently ignore
2019 	 * this event, so throw away result.
2020 	 */
2021 	(void) cmpxchg(&channel->sync_events_state, SYNC_EVENTS_REQUESTED,
2022 		       SYNC_EVENTS_VALID);
2023 }
2024 
efx_rx_buf_timestamp_minor(struct efx_nic * efx,const u8 * eh)2025 static inline u32 efx_rx_buf_timestamp_minor(struct efx_nic *efx, const u8 *eh)
2026 {
2027 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
2028 	return __le32_to_cpup((const __le32 *)(eh + efx->rx_packet_ts_offset));
2029 #else
2030 	const u8 *data = eh + efx->rx_packet_ts_offset;
2031 	return (u32)data[0]       |
2032 	       (u32)data[1] << 8  |
2033 	       (u32)data[2] << 16 |
2034 	       (u32)data[3] << 24;
2035 #endif
2036 }
2037 
__efx_rx_skb_attach_timestamp(struct efx_channel * channel,struct sk_buff * skb)2038 void __efx_rx_skb_attach_timestamp(struct efx_channel *channel,
2039 				   struct sk_buff *skb)
2040 {
2041 	struct efx_nic *efx = channel->efx;
2042 	struct efx_ptp_data *ptp = efx->ptp_data;
2043 	u32 pkt_timestamp_major, pkt_timestamp_minor;
2044 	u32 diff, carry;
2045 	struct skb_shared_hwtstamps *timestamps;
2046 
2047 	if (channel->sync_events_state != SYNC_EVENTS_VALID)
2048 		return;
2049 
2050 	pkt_timestamp_minor = efx_rx_buf_timestamp_minor(efx, skb_mac_header(skb));
2051 
2052 	/* get the difference between the packet and sync timestamps,
2053 	 * modulo one second
2054 	 */
2055 	diff = pkt_timestamp_minor - channel->sync_timestamp_minor;
2056 	if (pkt_timestamp_minor < channel->sync_timestamp_minor)
2057 		diff += ptp->nic_time.minor_max;
2058 
2059 	/* do we roll over a second boundary and need to carry the one? */
2060 	carry = (channel->sync_timestamp_minor >= ptp->nic_time.minor_max - diff) ?
2061 		1 : 0;
2062 
2063 	if (diff <= ptp->nic_time.sync_event_diff_max) {
2064 		/* packet is ahead of the sync event by a quarter of a second or
2065 		 * less (allowing for fuzz)
2066 		 */
2067 		pkt_timestamp_major = channel->sync_timestamp_major + carry;
2068 	} else if (diff >= ptp->nic_time.sync_event_diff_min) {
2069 		/* packet is behind the sync event but within the fuzz factor.
2070 		 * This means the RX packet and sync event crossed as they were
2071 		 * placed on the event queue, which can sometimes happen.
2072 		 */
2073 		pkt_timestamp_major = channel->sync_timestamp_major - 1 + carry;
2074 	} else {
2075 		/* it's outside tolerance in both directions. this might be
2076 		 * indicative of us missing sync events for some reason, so
2077 		 * we'll call it an error rather than risk giving a bogus
2078 		 * timestamp.
2079 		 */
2080 		netif_vdbg(efx, drv, efx->net_dev,
2081 			  "packet timestamp %x too far from sync event %x:%x\n",
2082 			  pkt_timestamp_minor, channel->sync_timestamp_major,
2083 			  channel->sync_timestamp_minor);
2084 		return;
2085 	}
2086 
2087 	/* attach the timestamps to the skb */
2088 	timestamps = skb_hwtstamps(skb);
2089 	timestamps->hwtstamp =
2090 		ptp->nic_to_kernel_time(pkt_timestamp_major,
2091 					pkt_timestamp_minor,
2092 					ptp->ts_corrections.general_rx);
2093 }
2094 
efx_phc_adjfine(struct ptp_clock_info * ptp,long scaled_ppm)2095 static int efx_phc_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
2096 {
2097 	struct efx_ptp_data *ptp_data = container_of(ptp,
2098 						     struct efx_ptp_data,
2099 						     phc_clock_info);
2100 	s32 delta = scaled_ppm_to_ppb(scaled_ppm);
2101 	struct efx_nic *efx = ptp_data->efx;
2102 	MCDI_DECLARE_BUF(inadj, MC_CMD_PTP_IN_ADJUST_LEN);
2103 	s64 adjustment_ns;
2104 	int rc;
2105 
2106 	if (delta > MAX_PPB)
2107 		delta = MAX_PPB;
2108 	else if (delta < -MAX_PPB)
2109 		delta = -MAX_PPB;
2110 
2111 	/* Convert ppb to fixed point ns taking care to round correctly. */
2112 	adjustment_ns = ((s64)delta * PPB_SCALE_WORD +
2113 			 (1 << (ptp_data->adjfreq_ppb_shift - 1))) >>
2114 			ptp_data->adjfreq_ppb_shift;
2115 
2116 	MCDI_SET_DWORD(inadj, PTP_IN_OP, MC_CMD_PTP_OP_ADJUST);
2117 	MCDI_SET_DWORD(inadj, PTP_IN_PERIPH_ID, 0);
2118 	MCDI_SET_QWORD(inadj, PTP_IN_ADJUST_FREQ, adjustment_ns);
2119 	MCDI_SET_DWORD(inadj, PTP_IN_ADJUST_SECONDS, 0);
2120 	MCDI_SET_DWORD(inadj, PTP_IN_ADJUST_NANOSECONDS, 0);
2121 	rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inadj, sizeof(inadj),
2122 			  NULL, 0, NULL);
2123 	if (rc != 0)
2124 		return rc;
2125 
2126 	ptp_data->current_adjfreq = adjustment_ns;
2127 	return 0;
2128 }
2129 
efx_phc_adjtime(struct ptp_clock_info * ptp,s64 delta)2130 static int efx_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
2131 {
2132 	u32 nic_major, nic_minor;
2133 	struct efx_ptp_data *ptp_data = container_of(ptp,
2134 						     struct efx_ptp_data,
2135 						     phc_clock_info);
2136 	struct efx_nic *efx = ptp_data->efx;
2137 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_ADJUST_LEN);
2138 
2139 	efx->ptp_data->ns_to_nic_time(delta, &nic_major, &nic_minor);
2140 
2141 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_ADJUST);
2142 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
2143 	MCDI_SET_QWORD(inbuf, PTP_IN_ADJUST_FREQ, ptp_data->current_adjfreq);
2144 	MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_MAJOR, nic_major);
2145 	MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_MINOR, nic_minor);
2146 	return efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
2147 			    NULL, 0, NULL);
2148 }
2149 
efx_phc_gettime(struct ptp_clock_info * ptp,struct timespec64 * ts)2150 static int efx_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
2151 {
2152 	struct efx_ptp_data *ptp_data = container_of(ptp,
2153 						     struct efx_ptp_data,
2154 						     phc_clock_info);
2155 	struct efx_nic *efx = ptp_data->efx;
2156 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_READ_NIC_TIME_LEN);
2157 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_READ_NIC_TIME_LEN);
2158 	int rc;
2159 	ktime_t kt;
2160 
2161 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_READ_NIC_TIME);
2162 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
2163 
2164 	rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
2165 			  outbuf, sizeof(outbuf), NULL);
2166 	if (rc != 0)
2167 		return rc;
2168 
2169 	kt = ptp_data->nic_to_kernel_time(
2170 		MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_MAJOR),
2171 		MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_MINOR), 0);
2172 	*ts = ktime_to_timespec64(kt);
2173 	return 0;
2174 }
2175 
efx_phc_settime(struct ptp_clock_info * ptp,const struct timespec64 * e_ts)2176 static int efx_phc_settime(struct ptp_clock_info *ptp,
2177 			   const struct timespec64 *e_ts)
2178 {
2179 	/* Get the current NIC time, efx_phc_gettime.
2180 	 * Subtract from the desired time to get the offset
2181 	 * call efx_phc_adjtime with the offset
2182 	 */
2183 	int rc;
2184 	struct timespec64 time_now;
2185 	struct timespec64 delta;
2186 
2187 	rc = efx_phc_gettime(ptp, &time_now);
2188 	if (rc != 0)
2189 		return rc;
2190 
2191 	delta = timespec64_sub(*e_ts, time_now);
2192 
2193 	rc = efx_phc_adjtime(ptp, timespec64_to_ns(&delta));
2194 	if (rc != 0)
2195 		return rc;
2196 
2197 	return 0;
2198 }
2199 
efx_phc_enable(struct ptp_clock_info * ptp,struct ptp_clock_request * request,int enable)2200 static int efx_phc_enable(struct ptp_clock_info *ptp,
2201 			  struct ptp_clock_request *request,
2202 			  int enable)
2203 {
2204 	struct efx_ptp_data *ptp_data = container_of(ptp,
2205 						     struct efx_ptp_data,
2206 						     phc_clock_info);
2207 	if (request->type != PTP_CLK_REQ_PPS)
2208 		return -EOPNOTSUPP;
2209 
2210 	ptp_data->nic_ts_enabled = !!enable;
2211 	return 0;
2212 }
2213 
2214 static const struct efx_channel_type efx_ptp_channel_type = {
2215 	.handle_no_channel	= efx_ptp_handle_no_channel,
2216 	.pre_probe		= efx_ptp_probe_channel,
2217 	.post_remove		= efx_ptp_remove_channel,
2218 	.get_name		= efx_ptp_get_channel_name,
2219 	.copy                   = efx_copy_channel,
2220 	.receive_skb		= efx_ptp_rx,
2221 	.want_txqs		= efx_ptp_want_txqs,
2222 	.keep_eventq		= false,
2223 };
2224 
efx_ptp_defer_probe_with_channel(struct efx_nic * efx)2225 void efx_ptp_defer_probe_with_channel(struct efx_nic *efx)
2226 {
2227 	/* Check whether PTP is implemented on this NIC.  The DISABLE
2228 	 * operation will succeed if and only if it is implemented.
2229 	 */
2230 	if (efx_ptp_disable(efx) == 0)
2231 		efx->extra_channel_type[EFX_EXTRA_CHANNEL_PTP] =
2232 			&efx_ptp_channel_type;
2233 }
2234 
efx_ptp_start_datapath(struct efx_nic * efx)2235 void efx_ptp_start_datapath(struct efx_nic *efx)
2236 {
2237 	if (efx_ptp_restart(efx))
2238 		netif_err(efx, drv, efx->net_dev, "Failed to restart PTP.\n");
2239 	/* re-enable timestamping if it was previously enabled */
2240 	if (efx->type->ptp_set_ts_sync_events)
2241 		efx->type->ptp_set_ts_sync_events(efx, true, true);
2242 }
2243 
efx_ptp_stop_datapath(struct efx_nic * efx)2244 void efx_ptp_stop_datapath(struct efx_nic *efx)
2245 {
2246 	/* temporarily disable timestamping */
2247 	if (efx->type->ptp_set_ts_sync_events)
2248 		efx->type->ptp_set_ts_sync_events(efx, false, true);
2249 	efx_ptp_stop(efx);
2250 }
2251