xref: /linux/drivers/net/ethernet/sfc/ptp.c (revision 9410645520e9b820069761f3450ef6661418e279)
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 
112 /* ff0e::181 */
113 static const struct in6_addr ptp_addr_ipv6 = { { {
114 	0xff, 0x0e, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0x01, 0x81 } } };
115 
116 /* 01-1B-19-00-00-00 */
117 static const u8 ptp_addr_ether[ETH_ALEN] __aligned(2) = {
118 	0x01, 0x1b, 0x19, 0x00, 0x00, 0x00 };
119 
120 #define PTP_EVENT_PORT		319
121 #define PTP_GENERAL_PORT	320
122 
123 /* Annoyingly the format of the version numbers are different between
124  * versions 1 and 2 so it isn't possible to simply look for 1 or 2.
125  */
126 #define	PTP_VERSION_V1		1
127 
128 #define	PTP_VERSION_V2		2
129 #define	PTP_VERSION_V2_MASK	0x0f
130 
131 enum ptp_packet_state {
132 	PTP_PACKET_STATE_UNMATCHED = 0,
133 	PTP_PACKET_STATE_MATCHED,
134 	PTP_PACKET_STATE_TIMED_OUT,
135 	PTP_PACKET_STATE_MATCH_UNWANTED
136 };
137 
138 /* NIC synchronised with single word of time only comprising
139  * partial seconds and full nanoseconds: 10^9 ~ 2^30 so 2 bits for seconds.
140  */
141 #define	MC_NANOSECOND_BITS	30
142 #define	MC_NANOSECOND_MASK	((1 << MC_NANOSECOND_BITS) - 1)
143 #define	MC_SECOND_MASK		((1 << (32 - MC_NANOSECOND_BITS)) - 1)
144 
145 /* Maximum parts-per-billion adjustment that is acceptable */
146 #define MAX_PPB			1000000
147 
148 /* Precalculate scale word to avoid long long division at runtime */
149 /* This is equivalent to 2^66 / 10^9. */
150 #define PPB_SCALE_WORD  ((1LL << (57)) / 1953125LL)
151 
152 /* How much to shift down after scaling to convert to FP40 */
153 #define PPB_SHIFT_FP40		26
154 /* ... and FP44. */
155 #define PPB_SHIFT_FP44		22
156 
157 #define PTP_SYNC_ATTEMPTS	4
158 
159 /**
160  * struct efx_ptp_match - Matching structure, stored in sk_buff's cb area.
161  * @expiry: Time after which the packet should be delivered irrespective of
162  *            event arrival.
163  * @state: The state of the packet - whether it is ready for processing or
164  *         whether that is of no interest.
165  */
166 struct efx_ptp_match {
167 	unsigned long expiry;
168 	enum ptp_packet_state state;
169 };
170 
171 /**
172  * struct efx_ptp_event_rx - A PTP receive event (from MC)
173  * @link: list of events
174  * @seq0: First part of (PTP) UUID
175  * @seq1: Second part of (PTP) UUID and sequence number
176  * @hwtimestamp: Event timestamp
177  * @expiry: Time which the packet arrived
178  */
179 struct efx_ptp_event_rx {
180 	struct list_head link;
181 	u32 seq0;
182 	u32 seq1;
183 	ktime_t hwtimestamp;
184 	unsigned long expiry;
185 };
186 
187 /**
188  * struct efx_ptp_timeset - Synchronisation between host and MC
189  * @host_start: Host time immediately before hardware timestamp taken
190  * @major: Hardware timestamp, major
191  * @minor: Hardware timestamp, minor
192  * @host_end: Host time immediately after hardware timestamp taken
193  * @wait: Number of NIC clock ticks between hardware timestamp being read and
194  *          host end time being seen
195  * @window: Difference of host_end and host_start
196  * @valid: Whether this timeset is valid
197  */
198 struct efx_ptp_timeset {
199 	u32 host_start;
200 	u32 major;
201 	u32 minor;
202 	u32 host_end;
203 	u32 wait;
204 	u32 window;	/* Derived: end - start, allowing for wrap */
205 };
206 
207 /**
208  * struct efx_ptp_rxfilter - Filter for PTP packets
209  * @list: Node of the list where the filter is added
210  * @ether_type: Network protocol of the filter (ETHER_P_IP / ETHER_P_IPV6)
211  * @loc_port: UDP port of the filter (PTP_EVENT_PORT / PTP_GENERAL_PORT)
212  * @loc_host: IPv4/v6 address of the filter
213  * @expiry: time when the filter expires, in jiffies
214  * @handle: Handle ID for the MCDI filters table
215  */
216 struct efx_ptp_rxfilter {
217 	struct list_head list;
218 	__be16 ether_type;
219 	__be16 loc_port;
220 	__be32 loc_host[4];
221 	unsigned long expiry;
222 	int handle;
223 };
224 
225 /**
226  * struct efx_ptp_data - Precision Time Protocol (PTP) state
227  * @efx: The NIC context
228  * @channel: The PTP channel (for Medford and Medford2)
229  * @rxq: Receive SKB queue (awaiting timestamps)
230  * @txq: Transmit SKB queue
231  * @workwq: Work queue for processing pending PTP operations
232  * @work: Work task
233  * @cleanup_work: Work task for periodic cleanup
234  * @reset_required: A serious error has occurred and the PTP task needs to be
235  *                  reset (disable, enable).
236  * @rxfilters_mcast: Receive filters for multicast PTP packets
237  * @rxfilters_ucast: Receive filters for unicast PTP packets
238  * @config: Current timestamp configuration
239  * @enabled: PTP operation enabled
240  * @mode: Mode in which PTP operating (PTP version)
241  * @ns_to_nic_time: Function to convert from scalar nanoseconds to NIC time
242  * @nic_to_kernel_time: Function to convert from NIC to kernel time
243  * @nic_time: contains time details
244  * @nic_time.minor_max: Wrap point for NIC minor times
245  * @nic_time.sync_event_diff_min: Minimum acceptable difference between time
246  * in packet prefix and last MCDI time sync event i.e. how much earlier than
247  * the last sync event time a packet timestamp can be.
248  * @nic_time.sync_event_diff_max: Maximum acceptable difference between time
249  * in packet prefix and last MCDI time sync event i.e. how much later than
250  * the last sync event time a packet timestamp can be.
251  * @nic_time.sync_event_minor_shift: Shift required to make minor time from
252  * field in MCDI time sync event.
253  * @min_synchronisation_ns: Minimum acceptable corrected sync window
254  * @capabilities: Capabilities flags from the NIC
255  * @ts_corrections: contains corrections details
256  * @ts_corrections.ptp_tx: Required driver correction of PTP packet transmit
257  *                         timestamps
258  * @ts_corrections.ptp_rx: Required driver correction of PTP packet receive
259  *                         timestamps
260  * @ts_corrections.pps_out: PPS output error (information only)
261  * @ts_corrections.pps_in: Required driver correction of PPS input timestamps
262  * @ts_corrections.general_tx: Required driver correction of general packet
263  *                             transmit timestamps
264  * @ts_corrections.general_rx: Required driver correction of general packet
265  *                             receive timestamps
266  * @evt_frags: Partly assembled PTP events
267  * @evt_frag_idx: Current fragment number
268  * @evt_code: Last event code
269  * @start: Address at which MC indicates ready for synchronisation
270  * @host_time_pps: Host time at last PPS
271  * @adjfreq_ppb_shift: Shift required to convert scaled parts-per-billion
272  * frequency adjustment into a fixed point fractional nanosecond format.
273  * @current_adjfreq: Current ppb adjustment.
274  * @phc_clock: Pointer to registered phc device (if primary function)
275  * @phc_clock_info: Registration structure for phc device
276  * @pps_work: pps work task for handling pps events
277  * @pps_workwq: pps work queue
278  * @nic_ts_enabled: Flag indicating if NIC generated TS events are handled
279  * @txbuf: Buffer for use when transmitting (PTP) packets to MC (avoids
280  *         allocations in main data path).
281  * @good_syncs: Number of successful synchronisations.
282  * @fast_syncs: Number of synchronisations requiring short delay
283  * @bad_syncs: Number of failed synchronisations.
284  * @sync_timeouts: Number of synchronisation timeouts
285  * @no_time_syncs: Number of synchronisations with no good times.
286  * @invalid_sync_windows: Number of sync windows with bad durations.
287  * @undersize_sync_windows: Number of corrected sync windows that are too small
288  * @oversize_sync_windows: Number of corrected sync windows that are too large
289  * @rx_no_timestamp: Number of packets received without a timestamp.
290  * @timeset: Last set of synchronisation statistics.
291  * @xmit_skb: Transmit SKB function.
292  */
293 struct efx_ptp_data {
294 	struct efx_nic *efx;
295 	struct efx_channel *channel;
296 	struct sk_buff_head rxq;
297 	struct sk_buff_head txq;
298 	struct workqueue_struct *workwq;
299 	struct work_struct work;
300 	struct delayed_work cleanup_work;
301 	bool reset_required;
302 	struct list_head rxfilters_mcast;
303 	struct list_head rxfilters_ucast;
304 	struct kernel_hwtstamp_config config;
305 	bool enabled;
306 	unsigned int mode;
307 	void (*ns_to_nic_time)(s64 ns, u32 *nic_major, u32 *nic_minor);
308 	ktime_t (*nic_to_kernel_time)(u32 nic_major, u32 nic_minor,
309 				      s32 correction);
310 	struct {
311 		u32 minor_max;
312 		u32 sync_event_diff_min;
313 		u32 sync_event_diff_max;
314 		unsigned int sync_event_minor_shift;
315 	} nic_time;
316 	unsigned int min_synchronisation_ns;
317 	unsigned int capabilities;
318 	struct {
319 		s32 ptp_tx;
320 		s32 ptp_rx;
321 		s32 pps_out;
322 		s32 pps_in;
323 		s32 general_tx;
324 		s32 general_rx;
325 	} ts_corrections;
326 	efx_qword_t evt_frags[MAX_EVENT_FRAGS];
327 	int evt_frag_idx;
328 	int evt_code;
329 	struct efx_buffer start;
330 	struct pps_event_time host_time_pps;
331 	unsigned int adjfreq_ppb_shift;
332 	s64 current_adjfreq;
333 	struct ptp_clock *phc_clock;
334 	struct ptp_clock_info phc_clock_info;
335 	struct work_struct pps_work;
336 	struct workqueue_struct *pps_workwq;
337 	bool nic_ts_enabled;
338 	efx_dword_t txbuf[MCDI_TX_BUF_LEN(MC_CMD_PTP_IN_TRANSMIT_LENMAX)];
339 
340 	unsigned int good_syncs;
341 	unsigned int fast_syncs;
342 	unsigned int bad_syncs;
343 	unsigned int sync_timeouts;
344 	unsigned int no_time_syncs;
345 	unsigned int invalid_sync_windows;
346 	unsigned int undersize_sync_windows;
347 	unsigned int oversize_sync_windows;
348 	unsigned int rx_no_timestamp;
349 	struct efx_ptp_timeset
350 	timeset[MC_CMD_PTP_OUT_SYNCHRONIZE_TIMESET_MAXNUM];
351 	void (*xmit_skb)(struct efx_nic *efx, struct sk_buff *skb);
352 };
353 
354 static int efx_phc_adjfine(struct ptp_clock_info *ptp, long scaled_ppm);
355 static int efx_phc_adjtime(struct ptp_clock_info *ptp, s64 delta);
356 static int efx_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts);
357 static int efx_phc_settime(struct ptp_clock_info *ptp,
358 			   const struct timespec64 *e_ts);
359 static int efx_phc_enable(struct ptp_clock_info *ptp,
360 			  struct ptp_clock_request *request, int on);
361 static int efx_ptp_insert_unicast_filter(struct efx_nic *efx,
362 					 struct sk_buff *skb);
363 
efx_ptp_use_mac_tx_timestamps(struct efx_nic * efx)364 bool efx_ptp_use_mac_tx_timestamps(struct efx_nic *efx)
365 {
366 	return efx_has_cap(efx, TX_MAC_TIMESTAMPING);
367 }
368 
369 /* PTP 'extra' channel is still a traffic channel, but we only create TX queues
370  * if PTP uses MAC TX timestamps, not if PTP uses the MC directly to transmit.
371  */
efx_ptp_want_txqs(struct efx_channel * channel)372 static bool efx_ptp_want_txqs(struct efx_channel *channel)
373 {
374 	return efx_ptp_use_mac_tx_timestamps(channel->efx);
375 }
376 
377 #define PTP_SW_STAT(ext_name, field_name)				\
378 	{ #ext_name, 0, offsetof(struct efx_ptp_data, field_name) }
379 #define PTP_MC_STAT(ext_name, mcdi_name)				\
380 	{ #ext_name, 32, MC_CMD_PTP_OUT_STATUS_STATS_ ## mcdi_name ## _OFST }
381 static const struct efx_hw_stat_desc efx_ptp_stat_desc[] = {
382 	PTP_SW_STAT(ptp_good_syncs, good_syncs),
383 	PTP_SW_STAT(ptp_fast_syncs, fast_syncs),
384 	PTP_SW_STAT(ptp_bad_syncs, bad_syncs),
385 	PTP_SW_STAT(ptp_sync_timeouts, sync_timeouts),
386 	PTP_SW_STAT(ptp_no_time_syncs, no_time_syncs),
387 	PTP_SW_STAT(ptp_invalid_sync_windows, invalid_sync_windows),
388 	PTP_SW_STAT(ptp_undersize_sync_windows, undersize_sync_windows),
389 	PTP_SW_STAT(ptp_oversize_sync_windows, oversize_sync_windows),
390 	PTP_SW_STAT(ptp_rx_no_timestamp, rx_no_timestamp),
391 	PTP_MC_STAT(ptp_tx_timestamp_packets, TX),
392 	PTP_MC_STAT(ptp_rx_timestamp_packets, RX),
393 	PTP_MC_STAT(ptp_timestamp_packets, TS),
394 	PTP_MC_STAT(ptp_filter_matches, FM),
395 	PTP_MC_STAT(ptp_non_filter_matches, NFM),
396 };
397 #define PTP_STAT_COUNT ARRAY_SIZE(efx_ptp_stat_desc)
398 static const unsigned long efx_ptp_stat_mask[] = {
399 	[0 ... BITS_TO_LONGS(PTP_STAT_COUNT) - 1] = ~0UL,
400 };
401 
efx_ptp_describe_stats(struct efx_nic * efx,u8 * strings)402 size_t efx_ptp_describe_stats(struct efx_nic *efx, u8 *strings)
403 {
404 	if (!efx->ptp_data)
405 		return 0;
406 
407 	return efx_nic_describe_stats(efx_ptp_stat_desc, PTP_STAT_COUNT,
408 				      efx_ptp_stat_mask, strings);
409 }
410 
efx_ptp_update_stats(struct efx_nic * efx,u64 * stats)411 size_t efx_ptp_update_stats(struct efx_nic *efx, u64 *stats)
412 {
413 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_STATUS_LEN);
414 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_STATUS_LEN);
415 	size_t i;
416 	int rc;
417 
418 	if (!efx->ptp_data)
419 		return 0;
420 
421 	/* Copy software statistics */
422 	for (i = 0; i < PTP_STAT_COUNT; i++) {
423 		if (efx_ptp_stat_desc[i].dma_width)
424 			continue;
425 		stats[i] = *(unsigned int *)((char *)efx->ptp_data +
426 					     efx_ptp_stat_desc[i].offset);
427 	}
428 
429 	/* Fetch MC statistics.  We *must* fill in all statistics or
430 	 * risk leaking kernel memory to userland, so if the MCDI
431 	 * request fails we pretend we got zeroes.
432 	 */
433 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_STATUS);
434 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
435 	rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
436 			  outbuf, sizeof(outbuf), NULL);
437 	if (rc)
438 		memset(outbuf, 0, sizeof(outbuf));
439 	efx_nic_update_stats(efx_ptp_stat_desc, PTP_STAT_COUNT,
440 			     efx_ptp_stat_mask,
441 			     stats, _MCDI_PTR(outbuf, 0), false);
442 
443 	return PTP_STAT_COUNT;
444 }
445 
446 /* To convert from s27 format to ns we multiply then divide by a power of 2.
447  * For the conversion from ns to s27, the operation is also converted to a
448  * multiply and shift.
449  */
450 #define S27_TO_NS_SHIFT	(27)
451 #define NS_TO_S27_MULT	(((1ULL << 63) + NSEC_PER_SEC / 2) / NSEC_PER_SEC)
452 #define NS_TO_S27_SHIFT	(63 - S27_TO_NS_SHIFT)
453 #define S27_MINOR_MAX	(1 << S27_TO_NS_SHIFT)
454 
455 /* For Huntington platforms NIC time is in seconds and fractions of a second
456  * where the minor register only uses 27 bits in units of 2^-27s.
457  */
efx_ptp_ns_to_s27(s64 ns,u32 * nic_major,u32 * nic_minor)458 static void efx_ptp_ns_to_s27(s64 ns, u32 *nic_major, u32 *nic_minor)
459 {
460 	struct timespec64 ts = ns_to_timespec64(ns);
461 	u32 maj = (u32)ts.tv_sec;
462 	u32 min = (u32)(((u64)ts.tv_nsec * NS_TO_S27_MULT +
463 			 (1ULL << (NS_TO_S27_SHIFT - 1))) >> NS_TO_S27_SHIFT);
464 
465 	/* The conversion can result in the minor value exceeding the maximum.
466 	 * In this case, round up to the next second.
467 	 */
468 	if (min >= S27_MINOR_MAX) {
469 		min -= S27_MINOR_MAX;
470 		maj++;
471 	}
472 
473 	*nic_major = maj;
474 	*nic_minor = min;
475 }
476 
efx_ptp_s27_to_ktime(u32 nic_major,u32 nic_minor)477 static inline ktime_t efx_ptp_s27_to_ktime(u32 nic_major, u32 nic_minor)
478 {
479 	u32 ns = (u32)(((u64)nic_minor * NSEC_PER_SEC +
480 			(1ULL << (S27_TO_NS_SHIFT - 1))) >> S27_TO_NS_SHIFT);
481 	return ktime_set(nic_major, ns);
482 }
483 
efx_ptp_s27_to_ktime_correction(u32 nic_major,u32 nic_minor,s32 correction)484 static ktime_t efx_ptp_s27_to_ktime_correction(u32 nic_major, u32 nic_minor,
485 					       s32 correction)
486 {
487 	/* Apply the correction and deal with carry */
488 	nic_minor += correction;
489 	if ((s32)nic_minor < 0) {
490 		nic_minor += S27_MINOR_MAX;
491 		nic_major--;
492 	} else if (nic_minor >= S27_MINOR_MAX) {
493 		nic_minor -= S27_MINOR_MAX;
494 		nic_major++;
495 	}
496 
497 	return efx_ptp_s27_to_ktime(nic_major, nic_minor);
498 }
499 
500 /* 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)501 static void efx_ptp_ns_to_s_qns(s64 ns, u32 *nic_major, u32 *nic_minor)
502 {
503 	struct timespec64 ts = ns_to_timespec64(ns);
504 
505 	*nic_major = (u32)ts.tv_sec;
506 	*nic_minor = ts.tv_nsec * 4;
507 }
508 
efx_ptp_s_qns_to_ktime_correction(u32 nic_major,u32 nic_minor,s32 correction)509 static ktime_t efx_ptp_s_qns_to_ktime_correction(u32 nic_major, u32 nic_minor,
510 						 s32 correction)
511 {
512 	ktime_t kt;
513 
514 	nic_minor = DIV_ROUND_CLOSEST(nic_minor, 4);
515 	correction = DIV_ROUND_CLOSEST(correction, 4);
516 
517 	kt = ktime_set(nic_major, nic_minor);
518 
519 	if (correction >= 0)
520 		kt = ktime_add_ns(kt, (u64)correction);
521 	else
522 		kt = ktime_sub_ns(kt, (u64)-correction);
523 	return kt;
524 }
525 
efx_ptp_channel(struct efx_nic * efx)526 struct efx_channel *efx_ptp_channel(struct efx_nic *efx)
527 {
528 	return efx->ptp_data ? efx->ptp_data->channel : NULL;
529 }
530 
efx_ptp_update_channel(struct efx_nic * efx,struct efx_channel * channel)531 void efx_ptp_update_channel(struct efx_nic *efx, struct efx_channel *channel)
532 {
533 	if (efx->ptp_data)
534 		efx->ptp_data->channel = channel;
535 }
536 
last_sync_timestamp_major(struct efx_nic * efx)537 static u32 last_sync_timestamp_major(struct efx_nic *efx)
538 {
539 	struct efx_channel *channel = efx_ptp_channel(efx);
540 	u32 major = 0;
541 
542 	if (channel)
543 		major = channel->sync_timestamp_major;
544 	return major;
545 }
546 
547 /* The 8000 series and later can provide the time from the MAC, which is only
548  * 48 bits long and provides meta-information in the top 2 bits.
549  */
550 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)551 efx_ptp_mac_nic_to_ktime_correction(struct efx_nic *efx,
552 				    struct efx_ptp_data *ptp,
553 				    u32 nic_major, u32 nic_minor,
554 				    s32 correction)
555 {
556 	u32 sync_timestamp;
557 	ktime_t kt = { 0 };
558 	s16 delta;
559 
560 	if (!(nic_major & 0x80000000)) {
561 		WARN_ON_ONCE(nic_major >> 16);
562 
563 		/* Medford provides 48 bits of timestamp, so we must get the top
564 		 * 16 bits from the timesync event state.
565 		 *
566 		 * We only have the lower 16 bits of the time now, but we do
567 		 * have a full resolution timestamp at some point in past. As
568 		 * long as the difference between the (real) now and the sync
569 		 * is less than 2^15, then we can reconstruct the difference
570 		 * between those two numbers using only the lower 16 bits of
571 		 * each.
572 		 *
573 		 * Put another way
574 		 *
575 		 * a - b = ((a mod k) - b) mod k
576 		 *
577 		 * when -k/2 < (a-b) < k/2. In our case k is 2^16. We know
578 		 * (a mod k) and b, so can calculate the delta, a - b.
579 		 *
580 		 */
581 		sync_timestamp = last_sync_timestamp_major(efx);
582 
583 		/* Because delta is s16 this does an implicit mask down to
584 		 * 16 bits which is what we need, assuming
585 		 * MEDFORD_TX_SECS_EVENT_BITS is 16. delta is signed so that
586 		 * we can deal with the (unlikely) case of sync timestamps
587 		 * arriving from the future.
588 		 */
589 		delta = nic_major - sync_timestamp;
590 
591 		/* Recover the fully specified time now, by applying the offset
592 		 * to the (fully specified) sync time.
593 		 */
594 		nic_major = sync_timestamp + delta;
595 
596 		kt = ptp->nic_to_kernel_time(nic_major, nic_minor,
597 					     correction);
598 	}
599 	return kt;
600 }
601 
efx_ptp_nic_to_kernel_time(struct efx_tx_queue * tx_queue)602 ktime_t efx_ptp_nic_to_kernel_time(struct efx_tx_queue *tx_queue)
603 {
604 	struct efx_nic *efx = tx_queue->efx;
605 	struct efx_ptp_data *ptp = efx->ptp_data;
606 	ktime_t kt;
607 
608 	if (efx_ptp_use_mac_tx_timestamps(efx))
609 		kt = efx_ptp_mac_nic_to_ktime_correction(efx, ptp,
610 				tx_queue->completed_timestamp_major,
611 				tx_queue->completed_timestamp_minor,
612 				ptp->ts_corrections.general_tx);
613 	else
614 		kt = ptp->nic_to_kernel_time(
615 				tx_queue->completed_timestamp_major,
616 				tx_queue->completed_timestamp_minor,
617 				ptp->ts_corrections.general_tx);
618 	return kt;
619 }
620 
621 /* Get PTP attributes and set up time conversions */
efx_ptp_get_attributes(struct efx_nic * efx)622 static int efx_ptp_get_attributes(struct efx_nic *efx)
623 {
624 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_GET_ATTRIBUTES_LEN);
625 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_GET_ATTRIBUTES_LEN);
626 	struct efx_ptp_data *ptp = efx->ptp_data;
627 	int rc;
628 	u32 fmt;
629 	size_t out_len;
630 
631 	/* Get the PTP attributes. If the NIC doesn't support the operation we
632 	 * use the default format for compatibility with older NICs i.e.
633 	 * seconds and nanoseconds.
634 	 */
635 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_GET_ATTRIBUTES);
636 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
637 	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
638 				outbuf, sizeof(outbuf), &out_len);
639 	if (rc == 0) {
640 		fmt = MCDI_DWORD(outbuf, PTP_OUT_GET_ATTRIBUTES_TIME_FORMAT);
641 	} else if (rc == -EINVAL) {
642 		fmt = MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_NANOSECONDS;
643 	} else if (rc == -EPERM) {
644 		pci_info(efx->pci_dev, "no PTP support\n");
645 		return rc;
646 	} else {
647 		efx_mcdi_display_error(efx, MC_CMD_PTP, sizeof(inbuf),
648 				       outbuf, sizeof(outbuf), rc);
649 		return rc;
650 	}
651 
652 	switch (fmt) {
653 	case MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_27FRACTION:
654 		ptp->ns_to_nic_time = efx_ptp_ns_to_s27;
655 		ptp->nic_to_kernel_time = efx_ptp_s27_to_ktime_correction;
656 		ptp->nic_time.minor_max = 1 << 27;
657 		ptp->nic_time.sync_event_minor_shift = 19;
658 		break;
659 	case MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_QTR_NANOSECONDS:
660 		ptp->ns_to_nic_time = efx_ptp_ns_to_s_qns;
661 		ptp->nic_to_kernel_time = efx_ptp_s_qns_to_ktime_correction;
662 		ptp->nic_time.minor_max = 4000000000UL;
663 		ptp->nic_time.sync_event_minor_shift = 24;
664 		break;
665 	default:
666 		return -ERANGE;
667 	}
668 
669 	/* Precalculate acceptable difference between the minor time in the
670 	 * packet prefix and the last MCDI time sync event. We expect the
671 	 * packet prefix timestamp to be after of sync event by up to one
672 	 * sync event interval (0.25s) but we allow it to exceed this by a
673 	 * fuzz factor of (0.1s)
674 	 */
675 	ptp->nic_time.sync_event_diff_min = ptp->nic_time.minor_max
676 		- (ptp->nic_time.minor_max / 10);
677 	ptp->nic_time.sync_event_diff_max = (ptp->nic_time.minor_max / 4)
678 		+ (ptp->nic_time.minor_max / 10);
679 
680 	/* MC_CMD_PTP_OP_GET_ATTRIBUTES has been extended twice from an older
681 	 * operation MC_CMD_PTP_OP_GET_TIME_FORMAT. The function now may return
682 	 * a value to use for the minimum acceptable corrected synchronization
683 	 * window and may return further capabilities.
684 	 * If we have the extra information store it. For older firmware that
685 	 * does not implement the extended command use the default value.
686 	 */
687 	if (rc == 0 &&
688 	    out_len >= MC_CMD_PTP_OUT_GET_ATTRIBUTES_CAPABILITIES_OFST)
689 		ptp->min_synchronisation_ns =
690 			MCDI_DWORD(outbuf,
691 				   PTP_OUT_GET_ATTRIBUTES_SYNC_WINDOW_MIN);
692 	else
693 		ptp->min_synchronisation_ns = DEFAULT_MIN_SYNCHRONISATION_NS;
694 
695 	if (rc == 0 &&
696 	    out_len >= MC_CMD_PTP_OUT_GET_ATTRIBUTES_LEN)
697 		ptp->capabilities = MCDI_DWORD(outbuf,
698 					PTP_OUT_GET_ATTRIBUTES_CAPABILITIES);
699 	else
700 		ptp->capabilities = 0;
701 
702 	/* Set up the shift for conversion between frequency
703 	 * adjustments in parts-per-billion and the fixed-point
704 	 * fractional ns format that the adapter uses.
705 	 */
706 	if (ptp->capabilities & (1 << MC_CMD_PTP_OUT_GET_ATTRIBUTES_FP44_FREQ_ADJ_LBN))
707 		ptp->adjfreq_ppb_shift = PPB_SHIFT_FP44;
708 	else
709 		ptp->adjfreq_ppb_shift = PPB_SHIFT_FP40;
710 
711 	return 0;
712 }
713 
714 /* Get PTP timestamp corrections */
efx_ptp_get_timestamp_corrections(struct efx_nic * efx)715 static int efx_ptp_get_timestamp_corrections(struct efx_nic *efx)
716 {
717 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_GET_TIMESTAMP_CORRECTIONS_LEN);
718 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_LEN);
719 	int rc;
720 	size_t out_len;
721 
722 	/* Get the timestamp corrections from the NIC. If this operation is
723 	 * not supported (older NICs) then no correction is required.
724 	 */
725 	MCDI_SET_DWORD(inbuf, PTP_IN_OP,
726 		       MC_CMD_PTP_OP_GET_TIMESTAMP_CORRECTIONS);
727 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
728 
729 	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
730 				outbuf, sizeof(outbuf), &out_len);
731 	if (rc == 0) {
732 		efx->ptp_data->ts_corrections.ptp_tx = MCDI_DWORD(outbuf,
733 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_TRANSMIT);
734 		efx->ptp_data->ts_corrections.ptp_rx = MCDI_DWORD(outbuf,
735 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_RECEIVE);
736 		efx->ptp_data->ts_corrections.pps_out = MCDI_DWORD(outbuf,
737 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_PPS_OUT);
738 		efx->ptp_data->ts_corrections.pps_in = MCDI_DWORD(outbuf,
739 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_PPS_IN);
740 
741 		if (out_len >= MC_CMD_PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_LEN) {
742 			efx->ptp_data->ts_corrections.general_tx = MCDI_DWORD(
743 				outbuf,
744 				PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_GENERAL_TX);
745 			efx->ptp_data->ts_corrections.general_rx = MCDI_DWORD(
746 				outbuf,
747 				PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_GENERAL_RX);
748 		} else {
749 			efx->ptp_data->ts_corrections.general_tx =
750 				efx->ptp_data->ts_corrections.ptp_tx;
751 			efx->ptp_data->ts_corrections.general_rx =
752 				efx->ptp_data->ts_corrections.ptp_rx;
753 		}
754 	} else if (rc == -EINVAL) {
755 		efx->ptp_data->ts_corrections.ptp_tx = 0;
756 		efx->ptp_data->ts_corrections.ptp_rx = 0;
757 		efx->ptp_data->ts_corrections.pps_out = 0;
758 		efx->ptp_data->ts_corrections.pps_in = 0;
759 		efx->ptp_data->ts_corrections.general_tx = 0;
760 		efx->ptp_data->ts_corrections.general_rx = 0;
761 	} else {
762 		efx_mcdi_display_error(efx, MC_CMD_PTP, sizeof(inbuf), outbuf,
763 				       sizeof(outbuf), rc);
764 		return rc;
765 	}
766 
767 	return 0;
768 }
769 
770 /* Enable MCDI PTP support. */
efx_ptp_enable(struct efx_nic * efx)771 static int efx_ptp_enable(struct efx_nic *efx)
772 {
773 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_ENABLE_LEN);
774 	MCDI_DECLARE_BUF_ERR(outbuf);
775 	int rc;
776 
777 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_ENABLE);
778 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
779 	MCDI_SET_DWORD(inbuf, PTP_IN_ENABLE_QUEUE,
780 		       efx->ptp_data->channel ?
781 		       efx->ptp_data->channel->channel : 0);
782 	MCDI_SET_DWORD(inbuf, PTP_IN_ENABLE_MODE, efx->ptp_data->mode);
783 
784 	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
785 				outbuf, sizeof(outbuf), NULL);
786 	rc = (rc == -EALREADY) ? 0 : rc;
787 	if (rc)
788 		efx_mcdi_display_error(efx, MC_CMD_PTP,
789 				       MC_CMD_PTP_IN_ENABLE_LEN,
790 				       outbuf, sizeof(outbuf), rc);
791 	return rc;
792 }
793 
794 /* Disable MCDI PTP support.
795  *
796  * Note that this function should never rely on the presence of ptp_data -
797  * may be called before that exists.
798  */
efx_ptp_disable(struct efx_nic * efx)799 static int efx_ptp_disable(struct efx_nic *efx)
800 {
801 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_DISABLE_LEN);
802 	MCDI_DECLARE_BUF_ERR(outbuf);
803 	int rc;
804 
805 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_DISABLE);
806 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
807 	rc = efx_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
808 				outbuf, sizeof(outbuf), NULL);
809 	rc = (rc == -EALREADY) ? 0 : rc;
810 	/* If we get ENOSYS, the NIC doesn't support PTP, and thus this function
811 	 * should only have been called during probe.
812 	 */
813 	if (rc == -ENOSYS || rc == -EPERM)
814 		pci_info(efx->pci_dev, "no PTP support\n");
815 	else if (rc)
816 		efx_mcdi_display_error(efx, MC_CMD_PTP,
817 				       MC_CMD_PTP_IN_DISABLE_LEN,
818 				       outbuf, sizeof(outbuf), rc);
819 	return rc;
820 }
821 
efx_ptp_deliver_rx_queue(struct sk_buff_head * q)822 static void efx_ptp_deliver_rx_queue(struct sk_buff_head *q)
823 {
824 	struct sk_buff *skb;
825 
826 	while ((skb = skb_dequeue(q))) {
827 		local_bh_disable();
828 		netif_receive_skb(skb);
829 		local_bh_enable();
830 	}
831 }
832 
efx_ptp_handle_no_channel(struct efx_nic * efx)833 static void efx_ptp_handle_no_channel(struct efx_nic *efx)
834 {
835 	netif_err(efx, drv, efx->net_dev,
836 		  "ERROR: PTP requires MSI-X and 1 additional interrupt"
837 		  "vector. PTP disabled\n");
838 }
839 
840 /* Repeatedly send the host time to the MC which will capture the hardware
841  * time.
842  */
efx_ptp_send_times(struct efx_nic * efx,struct pps_event_time * last_time)843 static void efx_ptp_send_times(struct efx_nic *efx,
844 			       struct pps_event_time *last_time)
845 {
846 	struct pps_event_time now;
847 	struct timespec64 limit;
848 	struct efx_ptp_data *ptp = efx->ptp_data;
849 	int *mc_running = ptp->start.addr;
850 
851 	pps_get_ts(&now);
852 	limit = now.ts_real;
853 	timespec64_add_ns(&limit, SYNCHRONISE_PERIOD_NS);
854 
855 	/* Write host time for specified period or until MC is done */
856 	while ((timespec64_compare(&now.ts_real, &limit) < 0) &&
857 	       READ_ONCE(*mc_running)) {
858 		struct timespec64 update_time;
859 		unsigned int host_time;
860 
861 		/* Don't update continuously to avoid saturating the PCIe bus */
862 		update_time = now.ts_real;
863 		timespec64_add_ns(&update_time, SYNCHRONISATION_GRANULARITY_NS);
864 		do {
865 			pps_get_ts(&now);
866 		} while ((timespec64_compare(&now.ts_real, &update_time) < 0) &&
867 			 READ_ONCE(*mc_running));
868 
869 		/* Synchronise NIC with single word of time only */
870 		host_time = (now.ts_real.tv_sec << MC_NANOSECOND_BITS |
871 			     now.ts_real.tv_nsec);
872 		/* Update host time in NIC memory */
873 		efx->type->ptp_write_host_time(efx, host_time);
874 	}
875 	*last_time = now;
876 }
877 
878 /* 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)879 static void efx_ptp_read_timeset(MCDI_DECLARE_STRUCT_PTR(data),
880 				 struct efx_ptp_timeset *timeset)
881 {
882 	unsigned start_ns, end_ns;
883 
884 	timeset->host_start = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTSTART);
885 	timeset->major = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_MAJOR);
886 	timeset->minor = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_MINOR);
887 	timeset->host_end = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTEND);
888 	timeset->wait = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_WAITNS);
889 
890 	/* Ignore seconds */
891 	start_ns = timeset->host_start & MC_NANOSECOND_MASK;
892 	end_ns = timeset->host_end & MC_NANOSECOND_MASK;
893 	/* Allow for rollover */
894 	if (end_ns < start_ns)
895 		end_ns += NSEC_PER_SEC;
896 	/* Determine duration of operation */
897 	timeset->window = end_ns - start_ns;
898 }
899 
900 /* Process times received from MC.
901  *
902  * Extract times from returned results, and establish the minimum value
903  * seen.  The minimum value represents the "best" possible time and events
904  * too much greater than this are rejected - the machine is, perhaps, too
905  * busy. A number of readings are taken so that, hopefully, at least one good
906  * synchronisation will be seen in the results.
907  */
908 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)909 efx_ptp_process_times(struct efx_nic *efx, MCDI_DECLARE_STRUCT_PTR(synch_buf),
910 		      size_t response_length,
911 		      const struct pps_event_time *last_time)
912 {
913 	unsigned number_readings =
914 		MCDI_VAR_ARRAY_LEN(response_length,
915 				   PTP_OUT_SYNCHRONIZE_TIMESET);
916 	unsigned i;
917 	unsigned ngood = 0;
918 	unsigned last_good = 0;
919 	struct efx_ptp_data *ptp = efx->ptp_data;
920 	u32 last_sec;
921 	u32 start_sec;
922 	struct timespec64 delta;
923 	ktime_t mc_time;
924 
925 	if (number_readings == 0)
926 		return -EAGAIN;
927 
928 	/* Read the set of results and find the last good host-MC
929 	 * synchronization result. The MC times when it finishes reading the
930 	 * host time so the corrected window time should be fairly constant
931 	 * for a given platform. Increment stats for any results that appear
932 	 * to be erroneous.
933 	 */
934 	for (i = 0; i < number_readings; i++) {
935 		s32 window, corrected;
936 		struct timespec64 wait;
937 
938 		efx_ptp_read_timeset(
939 			MCDI_ARRAY_STRUCT_PTR(synch_buf,
940 					      PTP_OUT_SYNCHRONIZE_TIMESET, i),
941 			&ptp->timeset[i]);
942 
943 		wait = ktime_to_timespec64(
944 			ptp->nic_to_kernel_time(0, ptp->timeset[i].wait, 0));
945 		window = ptp->timeset[i].window;
946 		corrected = window - wait.tv_nsec;
947 
948 		/* We expect the uncorrected synchronization window to be at
949 		 * least as large as the interval between host start and end
950 		 * times. If it is smaller than this then this is mostly likely
951 		 * to be a consequence of the host's time being adjusted.
952 		 * Check that the corrected sync window is in a reasonable
953 		 * range. If it is out of range it is likely to be because an
954 		 * interrupt or other delay occurred between reading the system
955 		 * time and writing it to MC memory.
956 		 */
957 		if (window < SYNCHRONISATION_GRANULARITY_NS) {
958 			++ptp->invalid_sync_windows;
959 		} else if (corrected >= MAX_SYNCHRONISATION_NS) {
960 			++ptp->oversize_sync_windows;
961 		} else if (corrected < ptp->min_synchronisation_ns) {
962 			++ptp->undersize_sync_windows;
963 		} else {
964 			ngood++;
965 			last_good = i;
966 		}
967 	}
968 
969 	if (ngood == 0) {
970 		netif_warn(efx, drv, efx->net_dev,
971 			   "PTP no suitable synchronisations\n");
972 		return -EAGAIN;
973 	}
974 
975 	/* Calculate delay from last good sync (host time) to last_time.
976 	 * It is possible that the seconds rolled over between taking
977 	 * the start reading and the last value written by the host.  The
978 	 * timescales are such that a gap of more than one second is never
979 	 * expected.  delta is *not* normalised.
980 	 */
981 	start_sec = ptp->timeset[last_good].host_start >> MC_NANOSECOND_BITS;
982 	last_sec = last_time->ts_real.tv_sec & MC_SECOND_MASK;
983 	if (start_sec != last_sec &&
984 	    ((start_sec + 1) & MC_SECOND_MASK) != last_sec) {
985 		netif_warn(efx, hw, efx->net_dev,
986 			   "PTP bad synchronisation seconds\n");
987 		return -EAGAIN;
988 	}
989 	delta.tv_sec = (last_sec - start_sec) & 1;
990 	delta.tv_nsec =
991 		last_time->ts_real.tv_nsec -
992 		(ptp->timeset[last_good].host_start & MC_NANOSECOND_MASK);
993 
994 	/* Convert the NIC time at last good sync into kernel time.
995 	 * No correction is required - this time is the output of a
996 	 * firmware process.
997 	 */
998 	mc_time = ptp->nic_to_kernel_time(ptp->timeset[last_good].major,
999 					  ptp->timeset[last_good].minor, 0);
1000 
1001 	/* Calculate delay from NIC top of second to last_time */
1002 	delta.tv_nsec += ktime_to_timespec64(mc_time).tv_nsec;
1003 
1004 	/* Set PPS timestamp to match NIC top of second */
1005 	ptp->host_time_pps = *last_time;
1006 	pps_sub_ts(&ptp->host_time_pps, delta);
1007 
1008 	return 0;
1009 }
1010 
1011 /* Synchronize times between the host and the MC */
efx_ptp_synchronize(struct efx_nic * efx,unsigned int num_readings)1012 static int efx_ptp_synchronize(struct efx_nic *efx, unsigned int num_readings)
1013 {
1014 	struct efx_ptp_data *ptp = efx->ptp_data;
1015 	MCDI_DECLARE_BUF(synch_buf, MC_CMD_PTP_OUT_SYNCHRONIZE_LENMAX);
1016 	size_t response_length;
1017 	int rc;
1018 	unsigned long timeout;
1019 	struct pps_event_time last_time = {};
1020 	unsigned int loops = 0;
1021 	int *start = ptp->start.addr;
1022 
1023 	MCDI_SET_DWORD(synch_buf, PTP_IN_OP, MC_CMD_PTP_OP_SYNCHRONIZE);
1024 	MCDI_SET_DWORD(synch_buf, PTP_IN_PERIPH_ID, 0);
1025 	MCDI_SET_DWORD(synch_buf, PTP_IN_SYNCHRONIZE_NUMTIMESETS,
1026 		       num_readings);
1027 	MCDI_SET_QWORD(synch_buf, PTP_IN_SYNCHRONIZE_START_ADDR,
1028 		       ptp->start.dma_addr);
1029 
1030 	/* Clear flag that signals MC ready */
1031 	WRITE_ONCE(*start, 0);
1032 	rc = efx_mcdi_rpc_start(efx, MC_CMD_PTP, synch_buf,
1033 				MC_CMD_PTP_IN_SYNCHRONIZE_LEN);
1034 	EFX_WARN_ON_ONCE_PARANOID(rc);
1035 
1036 	/* Wait for start from MCDI (or timeout) */
1037 	timeout = jiffies + msecs_to_jiffies(MAX_SYNCHRONISE_WAIT_MS);
1038 	while (!READ_ONCE(*start) && (time_before(jiffies, timeout))) {
1039 		udelay(20);	/* Usually start MCDI execution quickly */
1040 		loops++;
1041 	}
1042 
1043 	if (loops <= 1)
1044 		++ptp->fast_syncs;
1045 	if (!time_before(jiffies, timeout))
1046 		++ptp->sync_timeouts;
1047 
1048 	if (READ_ONCE(*start))
1049 		efx_ptp_send_times(efx, &last_time);
1050 
1051 	/* Collect results */
1052 	rc = efx_mcdi_rpc_finish(efx, MC_CMD_PTP,
1053 				 MC_CMD_PTP_IN_SYNCHRONIZE_LEN,
1054 				 synch_buf, sizeof(synch_buf),
1055 				 &response_length);
1056 	if (rc == 0) {
1057 		rc = efx_ptp_process_times(efx, synch_buf, response_length,
1058 					   &last_time);
1059 		if (rc == 0)
1060 			++ptp->good_syncs;
1061 		else
1062 			++ptp->no_time_syncs;
1063 	}
1064 
1065 	/* Increment the bad syncs counter if the synchronize fails, whatever
1066 	 * the reason.
1067 	 */
1068 	if (rc != 0)
1069 		++ptp->bad_syncs;
1070 
1071 	return rc;
1072 }
1073 
1074 /* Transmit a PTP packet via the dedicated hardware timestamped queue. */
efx_ptp_xmit_skb_queue(struct efx_nic * efx,struct sk_buff * skb)1075 static void efx_ptp_xmit_skb_queue(struct efx_nic *efx, struct sk_buff *skb)
1076 {
1077 	struct efx_ptp_data *ptp_data = efx->ptp_data;
1078 	u8 type = efx_tx_csum_type_skb(skb);
1079 	struct efx_tx_queue *tx_queue;
1080 
1081 	tx_queue = efx_channel_get_tx_queue(ptp_data->channel, type);
1082 	if (tx_queue && tx_queue->timestamping) {
1083 		skb_get(skb);
1084 
1085 		/* This code invokes normal driver TX code which is always
1086 		 * protected from softirqs when called from generic TX code,
1087 		 * which in turn disables preemption. Look at __dev_queue_xmit
1088 		 * which uses rcu_read_lock_bh disabling preemption for RCU
1089 		 * plus disabling softirqs. We do not need RCU reader
1090 		 * protection here.
1091 		 *
1092 		 * Although it is theoretically safe for current PTP TX/RX code
1093 		 * running without disabling softirqs, there are three good
1094 		 * reasond for doing so:
1095 		 *
1096 		 *      1) The code invoked is mainly implemented for non-PTP
1097 		 *         packets and it is always executed with softirqs
1098 		 *         disabled.
1099 		 *      2) This being a single PTP packet, better to not
1100 		 *         interrupt its processing by softirqs which can lead
1101 		 *         to high latencies.
1102 		 *      3) netdev_xmit_more checks preemption is disabled and
1103 		 *         triggers a BUG_ON if not.
1104 		 */
1105 		local_bh_disable();
1106 		efx_enqueue_skb(tx_queue, skb);
1107 		local_bh_enable();
1108 
1109 		/* We need to add the filters after enqueuing the packet.
1110 		 * Otherwise, there's high latency in sending back the
1111 		 * timestamp, causing ptp4l timeouts
1112 		 */
1113 		efx_ptp_insert_unicast_filter(efx, skb);
1114 		dev_consume_skb_any(skb);
1115 	} else {
1116 		WARN_ONCE(1, "PTP channel has no timestamped tx queue\n");
1117 		dev_kfree_skb_any(skb);
1118 	}
1119 }
1120 
1121 /* Transmit a PTP packet, via the MCDI interface, to the wire. */
efx_ptp_xmit_skb_mc(struct efx_nic * efx,struct sk_buff * skb)1122 static void efx_ptp_xmit_skb_mc(struct efx_nic *efx, struct sk_buff *skb)
1123 {
1124 	MCDI_DECLARE_BUF(txtime, MC_CMD_PTP_OUT_TRANSMIT_LEN);
1125 	struct efx_ptp_data *ptp_data = efx->ptp_data;
1126 	struct skb_shared_hwtstamps timestamps;
1127 	size_t len;
1128 	int rc;
1129 
1130 	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_OP, MC_CMD_PTP_OP_TRANSMIT);
1131 	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_PERIPH_ID, 0);
1132 	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_TRANSMIT_LENGTH, skb->len);
1133 	if (skb_shinfo(skb)->nr_frags != 0) {
1134 		rc = skb_linearize(skb);
1135 		if (rc != 0)
1136 			goto fail;
1137 	}
1138 
1139 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
1140 		rc = skb_checksum_help(skb);
1141 		if (rc != 0)
1142 			goto fail;
1143 	}
1144 	skb_copy_from_linear_data(skb,
1145 				  MCDI_PTR(ptp_data->txbuf,
1146 					   PTP_IN_TRANSMIT_PACKET),
1147 				  skb->len);
1148 	rc = efx_mcdi_rpc(efx, MC_CMD_PTP,
1149 			  ptp_data->txbuf, MC_CMD_PTP_IN_TRANSMIT_LEN(skb->len),
1150 			  txtime, sizeof(txtime), &len);
1151 	if (rc != 0)
1152 		goto fail;
1153 
1154 	memset(&timestamps, 0, sizeof(timestamps));
1155 	timestamps.hwtstamp = ptp_data->nic_to_kernel_time(
1156 		MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_MAJOR),
1157 		MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_MINOR),
1158 		ptp_data->ts_corrections.ptp_tx);
1159 
1160 	skb_tstamp_tx(skb, &timestamps);
1161 
1162 	/* Add the filters after sending back the timestamp to avoid delaying it
1163 	 * or ptp4l may timeout.
1164 	 */
1165 	efx_ptp_insert_unicast_filter(efx, skb);
1166 
1167 fail:
1168 	dev_kfree_skb_any(skb);
1169 
1170 	return;
1171 }
1172 
1173 /* Process any queued receive events and corresponding packets
1174  *
1175  * q is returned with all the packets that are ready for delivery.
1176  */
efx_ptp_process_events(struct efx_nic * efx,struct sk_buff_head * q)1177 static void efx_ptp_process_events(struct efx_nic *efx, struct sk_buff_head *q)
1178 {
1179 	struct efx_ptp_data *ptp = efx->ptp_data;
1180 	struct sk_buff *skb;
1181 
1182 	while ((skb = skb_dequeue(&ptp->rxq))) {
1183 		struct efx_ptp_match *match;
1184 
1185 		match = (struct efx_ptp_match *)skb->cb;
1186 		if (match->state == PTP_PACKET_STATE_MATCH_UNWANTED) {
1187 			__skb_queue_tail(q, skb);
1188 		} else if (time_after(jiffies, match->expiry)) {
1189 			match->state = PTP_PACKET_STATE_TIMED_OUT;
1190 			++ptp->rx_no_timestamp;
1191 			__skb_queue_tail(q, skb);
1192 		} else {
1193 			/* Replace unprocessed entry and stop */
1194 			skb_queue_head(&ptp->rxq, skb);
1195 			break;
1196 		}
1197 	}
1198 }
1199 
1200 /* Complete processing of a received packet */
efx_ptp_process_rx(struct efx_nic * efx,struct sk_buff * skb)1201 static inline void efx_ptp_process_rx(struct efx_nic *efx, struct sk_buff *skb)
1202 {
1203 	local_bh_disable();
1204 	netif_receive_skb(skb);
1205 	local_bh_enable();
1206 }
1207 
1208 static struct efx_ptp_rxfilter *
efx_ptp_find_filter(struct list_head * filter_list,struct efx_filter_spec * spec)1209 efx_ptp_find_filter(struct list_head *filter_list, struct efx_filter_spec *spec)
1210 {
1211 	struct efx_ptp_rxfilter *rxfilter;
1212 
1213 	list_for_each_entry(rxfilter, filter_list, list) {
1214 		if (rxfilter->ether_type == spec->ether_type &&
1215 		    rxfilter->loc_port == spec->loc_port &&
1216 		    !memcmp(rxfilter->loc_host, spec->loc_host, sizeof(spec->loc_host)))
1217 			return rxfilter;
1218 	}
1219 
1220 	return NULL;
1221 }
1222 
efx_ptp_remove_one_filter(struct efx_nic * efx,struct efx_ptp_rxfilter * rxfilter)1223 static void efx_ptp_remove_one_filter(struct efx_nic *efx,
1224 				      struct efx_ptp_rxfilter *rxfilter)
1225 {
1226 	efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED,
1227 				  rxfilter->handle);
1228 	list_del(&rxfilter->list);
1229 	kfree(rxfilter);
1230 }
1231 
efx_ptp_remove_filters(struct efx_nic * efx,struct list_head * filter_list)1232 static void efx_ptp_remove_filters(struct efx_nic *efx,
1233 				   struct list_head *filter_list)
1234 {
1235 	struct efx_ptp_rxfilter *rxfilter, *tmp;
1236 
1237 	list_for_each_entry_safe(rxfilter, tmp, filter_list, list)
1238 		efx_ptp_remove_one_filter(efx, rxfilter);
1239 }
1240 
efx_ptp_init_filter(struct efx_nic * efx,struct efx_filter_spec * rxfilter)1241 static void efx_ptp_init_filter(struct efx_nic *efx,
1242 				struct efx_filter_spec *rxfilter)
1243 {
1244 	struct efx_channel *channel = efx->ptp_data->channel;
1245 	struct efx_rx_queue *queue = efx_channel_get_rx_queue(channel);
1246 
1247 	efx_filter_init_rx(rxfilter, EFX_FILTER_PRI_REQUIRED, 0,
1248 			   efx_rx_queue_index(queue));
1249 }
1250 
efx_ptp_insert_filter(struct efx_nic * efx,struct list_head * filter_list,struct efx_filter_spec * spec,unsigned long expiry)1251 static int efx_ptp_insert_filter(struct efx_nic *efx,
1252 				 struct list_head *filter_list,
1253 				 struct efx_filter_spec *spec,
1254 				 unsigned long expiry)
1255 {
1256 	struct efx_ptp_data *ptp = efx->ptp_data;
1257 	struct efx_ptp_rxfilter *rxfilter;
1258 	int rc;
1259 
1260 	rxfilter = efx_ptp_find_filter(filter_list, spec);
1261 	if (rxfilter) {
1262 		rxfilter->expiry = expiry;
1263 		return 0;
1264 	}
1265 
1266 	rxfilter = kzalloc(sizeof(*rxfilter), GFP_KERNEL);
1267 	if (!rxfilter)
1268 		return -ENOMEM;
1269 
1270 	rc = efx_filter_insert_filter(efx, spec, true);
1271 	if (rc < 0)
1272 		goto fail;
1273 
1274 	rxfilter->handle = rc;
1275 	rxfilter->ether_type = spec->ether_type;
1276 	rxfilter->loc_port = spec->loc_port;
1277 	memcpy(rxfilter->loc_host, spec->loc_host, sizeof(spec->loc_host));
1278 	rxfilter->expiry = expiry;
1279 	list_add(&rxfilter->list, filter_list);
1280 
1281 	queue_delayed_work(ptp->workwq, &ptp->cleanup_work,
1282 			   UCAST_FILTER_EXPIRY_JIFFIES + 1);
1283 
1284 	return 0;
1285 
1286 fail:
1287 	kfree(rxfilter);
1288 	return rc;
1289 }
1290 
efx_ptp_insert_ipv4_filter(struct efx_nic * efx,struct list_head * filter_list,__be32 addr,u16 port,unsigned long expiry)1291 static int efx_ptp_insert_ipv4_filter(struct efx_nic *efx,
1292 				      struct list_head *filter_list,
1293 				      __be32 addr, u16 port,
1294 				      unsigned long expiry)
1295 {
1296 	struct efx_filter_spec spec;
1297 
1298 	efx_ptp_init_filter(efx, &spec);
1299 	efx_filter_set_ipv4_local(&spec, IPPROTO_UDP, addr, htons(port));
1300 	return efx_ptp_insert_filter(efx, filter_list, &spec, expiry);
1301 }
1302 
efx_ptp_insert_ipv6_filter(struct efx_nic * efx,struct list_head * filter_list,const struct in6_addr * addr,u16 port,unsigned long expiry)1303 static int efx_ptp_insert_ipv6_filter(struct efx_nic *efx,
1304 				      struct list_head *filter_list,
1305 				      const struct in6_addr *addr, u16 port,
1306 				      unsigned long expiry)
1307 {
1308 	struct efx_filter_spec spec;
1309 
1310 	efx_ptp_init_filter(efx, &spec);
1311 	efx_filter_set_ipv6_local(&spec, IPPROTO_UDP, addr, htons(port));
1312 	return efx_ptp_insert_filter(efx, filter_list, &spec, expiry);
1313 }
1314 
efx_ptp_insert_eth_multicast_filter(struct efx_nic * efx)1315 static int efx_ptp_insert_eth_multicast_filter(struct efx_nic *efx)
1316 {
1317 	struct efx_ptp_data *ptp = efx->ptp_data;
1318 	struct efx_filter_spec spec;
1319 
1320 	efx_ptp_init_filter(efx, &spec);
1321 	efx_filter_set_eth_local(&spec, EFX_FILTER_VID_UNSPEC, ptp_addr_ether);
1322 	spec.match_flags |= EFX_FILTER_MATCH_ETHER_TYPE;
1323 	spec.ether_type = htons(ETH_P_1588);
1324 	return efx_ptp_insert_filter(efx, &ptp->rxfilters_mcast, &spec, 0);
1325 }
1326 
efx_ptp_insert_multicast_filters(struct efx_nic * efx)1327 static int efx_ptp_insert_multicast_filters(struct efx_nic *efx)
1328 {
1329 	struct efx_ptp_data *ptp = efx->ptp_data;
1330 	int rc;
1331 
1332 	if (!ptp->channel || !list_empty(&ptp->rxfilters_mcast))
1333 		return 0;
1334 
1335 	/* Must filter on both event and general ports to ensure
1336 	 * that there is no packet re-ordering.
1337 	 */
1338 	rc = efx_ptp_insert_ipv4_filter(efx, &ptp->rxfilters_mcast,
1339 					htonl(PTP_ADDR_IPV4), PTP_EVENT_PORT,
1340 					0);
1341 	if (rc < 0)
1342 		goto fail;
1343 
1344 	rc = efx_ptp_insert_ipv4_filter(efx, &ptp->rxfilters_mcast,
1345 					htonl(PTP_ADDR_IPV4), PTP_GENERAL_PORT,
1346 					0);
1347 	if (rc < 0)
1348 		goto fail;
1349 
1350 	/* if the NIC supports hw timestamps by the MAC, we can support
1351 	 * PTP over IPv6 and Ethernet
1352 	 */
1353 	if (efx_ptp_use_mac_tx_timestamps(efx)) {
1354 		rc = efx_ptp_insert_ipv6_filter(efx, &ptp->rxfilters_mcast,
1355 						&ptp_addr_ipv6, PTP_EVENT_PORT, 0);
1356 		if (rc < 0)
1357 			goto fail;
1358 
1359 		rc = efx_ptp_insert_ipv6_filter(efx, &ptp->rxfilters_mcast,
1360 						&ptp_addr_ipv6, PTP_GENERAL_PORT, 0);
1361 		if (rc < 0)
1362 			goto fail;
1363 
1364 		rc = efx_ptp_insert_eth_multicast_filter(efx);
1365 
1366 		/* Not all firmware variants support this filter */
1367 		if (rc < 0 && rc != -EPROTONOSUPPORT)
1368 			goto fail;
1369 	}
1370 
1371 	return 0;
1372 
1373 fail:
1374 	efx_ptp_remove_filters(efx, &ptp->rxfilters_mcast);
1375 	return rc;
1376 }
1377 
efx_ptp_valid_unicast_event_pkt(struct sk_buff * skb)1378 static bool efx_ptp_valid_unicast_event_pkt(struct sk_buff *skb)
1379 {
1380 	if (skb->protocol == htons(ETH_P_IP)) {
1381 		return ip_hdr(skb)->daddr != htonl(PTP_ADDR_IPV4) &&
1382 			ip_hdr(skb)->protocol == IPPROTO_UDP &&
1383 			udp_hdr(skb)->source == htons(PTP_EVENT_PORT);
1384 	} else if (skb->protocol == htons(ETH_P_IPV6)) {
1385 		return !ipv6_addr_equal(&ipv6_hdr(skb)->daddr, &ptp_addr_ipv6) &&
1386 			ipv6_hdr(skb)->nexthdr == IPPROTO_UDP &&
1387 			udp_hdr(skb)->source == htons(PTP_EVENT_PORT);
1388 	}
1389 	return false;
1390 }
1391 
efx_ptp_insert_unicast_filter(struct efx_nic * efx,struct sk_buff * skb)1392 static int efx_ptp_insert_unicast_filter(struct efx_nic *efx,
1393 					 struct sk_buff *skb)
1394 {
1395 	struct efx_ptp_data *ptp = efx->ptp_data;
1396 	unsigned long expiry;
1397 	int rc;
1398 
1399 	if (!efx_ptp_valid_unicast_event_pkt(skb))
1400 		return -EINVAL;
1401 
1402 	expiry = jiffies + UCAST_FILTER_EXPIRY_JIFFIES;
1403 
1404 	if (skb->protocol == htons(ETH_P_IP)) {
1405 		__be32 addr = ip_hdr(skb)->saddr;
1406 
1407 		rc = efx_ptp_insert_ipv4_filter(efx, &ptp->rxfilters_ucast,
1408 						addr, PTP_EVENT_PORT, expiry);
1409 		if (rc < 0)
1410 			goto out;
1411 
1412 		rc = efx_ptp_insert_ipv4_filter(efx, &ptp->rxfilters_ucast,
1413 						addr, PTP_GENERAL_PORT, expiry);
1414 	} else if (efx_ptp_use_mac_tx_timestamps(efx)) {
1415 		/* IPv6 PTP only supported by devices with MAC hw timestamp */
1416 		struct in6_addr *addr = &ipv6_hdr(skb)->saddr;
1417 
1418 		rc = efx_ptp_insert_ipv6_filter(efx, &ptp->rxfilters_ucast,
1419 						addr, PTP_EVENT_PORT, expiry);
1420 		if (rc < 0)
1421 			goto out;
1422 
1423 		rc = efx_ptp_insert_ipv6_filter(efx, &ptp->rxfilters_ucast,
1424 						addr, PTP_GENERAL_PORT, expiry);
1425 	} else {
1426 		return -EOPNOTSUPP;
1427 	}
1428 
1429 out:
1430 	return rc;
1431 }
1432 
efx_ptp_start(struct efx_nic * efx)1433 static int efx_ptp_start(struct efx_nic *efx)
1434 {
1435 	struct efx_ptp_data *ptp = efx->ptp_data;
1436 	int rc;
1437 
1438 	ptp->reset_required = false;
1439 
1440 	rc = efx_ptp_insert_multicast_filters(efx);
1441 	if (rc)
1442 		return rc;
1443 
1444 	rc = efx_ptp_enable(efx);
1445 	if (rc != 0)
1446 		goto fail;
1447 
1448 	ptp->evt_frag_idx = 0;
1449 	ptp->current_adjfreq = 0;
1450 
1451 	return 0;
1452 
1453 fail:
1454 	efx_ptp_remove_filters(efx, &ptp->rxfilters_mcast);
1455 	return rc;
1456 }
1457 
efx_ptp_stop(struct efx_nic * efx)1458 static int efx_ptp_stop(struct efx_nic *efx)
1459 {
1460 	struct efx_ptp_data *ptp = efx->ptp_data;
1461 	int rc;
1462 
1463 	if (ptp == NULL)
1464 		return 0;
1465 
1466 	rc = efx_ptp_disable(efx);
1467 
1468 	efx_ptp_remove_filters(efx, &ptp->rxfilters_mcast);
1469 	efx_ptp_remove_filters(efx, &ptp->rxfilters_ucast);
1470 
1471 	/* Make sure RX packets are really delivered */
1472 	efx_ptp_deliver_rx_queue(&efx->ptp_data->rxq);
1473 	skb_queue_purge(&efx->ptp_data->txq);
1474 
1475 	return rc;
1476 }
1477 
efx_ptp_restart(struct efx_nic * efx)1478 static int efx_ptp_restart(struct efx_nic *efx)
1479 {
1480 	if (efx->ptp_data && efx->ptp_data->enabled)
1481 		return efx_ptp_start(efx);
1482 	return 0;
1483 }
1484 
efx_ptp_pps_worker(struct work_struct * work)1485 static void efx_ptp_pps_worker(struct work_struct *work)
1486 {
1487 	struct efx_ptp_data *ptp =
1488 		container_of(work, struct efx_ptp_data, pps_work);
1489 	struct efx_nic *efx = ptp->efx;
1490 	struct ptp_clock_event ptp_evt;
1491 
1492 	if (efx_ptp_synchronize(efx, PTP_SYNC_ATTEMPTS))
1493 		return;
1494 
1495 	ptp_evt.type = PTP_CLOCK_PPSUSR;
1496 	ptp_evt.pps_times = ptp->host_time_pps;
1497 	ptp_clock_event(ptp->phc_clock, &ptp_evt);
1498 }
1499 
efx_ptp_worker(struct work_struct * work)1500 static void efx_ptp_worker(struct work_struct *work)
1501 {
1502 	struct efx_ptp_data *ptp_data =
1503 		container_of(work, struct efx_ptp_data, work);
1504 	struct efx_nic *efx = ptp_data->efx;
1505 	struct sk_buff *skb;
1506 	struct sk_buff_head tempq;
1507 
1508 	if (ptp_data->reset_required) {
1509 		efx_ptp_stop(efx);
1510 		efx_ptp_start(efx);
1511 		return;
1512 	}
1513 
1514 	__skb_queue_head_init(&tempq);
1515 	efx_ptp_process_events(efx, &tempq);
1516 
1517 	while ((skb = skb_dequeue(&ptp_data->txq)))
1518 		ptp_data->xmit_skb(efx, skb);
1519 
1520 	while ((skb = __skb_dequeue(&tempq)))
1521 		efx_ptp_process_rx(efx, skb);
1522 }
1523 
efx_ptp_cleanup_worker(struct work_struct * work)1524 static void efx_ptp_cleanup_worker(struct work_struct *work)
1525 {
1526 	struct efx_ptp_data *ptp =
1527 		container_of(work, struct efx_ptp_data, cleanup_work.work);
1528 	struct efx_ptp_rxfilter *rxfilter, *tmp;
1529 
1530 	list_for_each_entry_safe(rxfilter, tmp, &ptp->rxfilters_ucast, list) {
1531 		if (time_is_before_jiffies(rxfilter->expiry))
1532 			efx_ptp_remove_one_filter(ptp->efx, rxfilter);
1533 	}
1534 
1535 	if (!list_empty(&ptp->rxfilters_ucast)) {
1536 		queue_delayed_work(ptp->workwq, &ptp->cleanup_work,
1537 				   UCAST_FILTER_EXPIRY_JIFFIES + 1);
1538 	}
1539 }
1540 
1541 static const struct ptp_clock_info efx_phc_clock_info = {
1542 	.owner		= THIS_MODULE,
1543 	.name		= "sfc",
1544 	.max_adj	= MAX_PPB,
1545 	.n_alarm	= 0,
1546 	.n_ext_ts	= 0,
1547 	.n_per_out	= 0,
1548 	.n_pins		= 0,
1549 	.pps		= 1,
1550 	.adjfine	= efx_phc_adjfine,
1551 	.adjtime	= efx_phc_adjtime,
1552 	.gettime64	= efx_phc_gettime,
1553 	.settime64	= efx_phc_settime,
1554 	.enable		= efx_phc_enable,
1555 };
1556 
1557 /* Initialise PTP state. */
efx_ptp_probe(struct efx_nic * efx,struct efx_channel * channel)1558 int efx_ptp_probe(struct efx_nic *efx, struct efx_channel *channel)
1559 {
1560 	struct efx_ptp_data *ptp;
1561 	int rc = 0;
1562 
1563 	if (efx->ptp_data) {
1564 		efx->ptp_data->channel = channel;
1565 		return 0;
1566 	}
1567 
1568 	ptp = kzalloc(sizeof(struct efx_ptp_data), GFP_KERNEL);
1569 	efx->ptp_data = ptp;
1570 	if (!efx->ptp_data)
1571 		return -ENOMEM;
1572 
1573 	ptp->efx = efx;
1574 	ptp->channel = channel;
1575 
1576 	rc = efx_nic_alloc_buffer(efx, &ptp->start, sizeof(int), GFP_KERNEL);
1577 	if (rc != 0)
1578 		goto fail1;
1579 
1580 	skb_queue_head_init(&ptp->rxq);
1581 	skb_queue_head_init(&ptp->txq);
1582 	ptp->workwq = create_singlethread_workqueue("sfc_ptp");
1583 	if (!ptp->workwq) {
1584 		rc = -ENOMEM;
1585 		goto fail2;
1586 	}
1587 
1588 	if (efx_ptp_use_mac_tx_timestamps(efx)) {
1589 		ptp->xmit_skb = efx_ptp_xmit_skb_queue;
1590 		/* Request sync events on this channel. */
1591 		channel->sync_events_state = SYNC_EVENTS_QUIESCENT;
1592 	} else {
1593 		ptp->xmit_skb = efx_ptp_xmit_skb_mc;
1594 	}
1595 
1596 	INIT_WORK(&ptp->work, efx_ptp_worker);
1597 	INIT_DELAYED_WORK(&ptp->cleanup_work, efx_ptp_cleanup_worker);
1598 	ptp->config.flags = 0;
1599 	ptp->config.tx_type = HWTSTAMP_TX_OFF;
1600 	ptp->config.rx_filter = HWTSTAMP_FILTER_NONE;
1601 	INIT_LIST_HEAD(&ptp->rxfilters_mcast);
1602 	INIT_LIST_HEAD(&ptp->rxfilters_ucast);
1603 
1604 	/* Get the NIC PTP attributes and set up time conversions */
1605 	rc = efx_ptp_get_attributes(efx);
1606 	if (rc < 0)
1607 		goto fail3;
1608 
1609 	/* Get the timestamp corrections */
1610 	rc = efx_ptp_get_timestamp_corrections(efx);
1611 	if (rc < 0)
1612 		goto fail3;
1613 
1614 	if (efx->mcdi->fn_flags &
1615 	    (1 << MC_CMD_DRV_ATTACH_EXT_OUT_FLAG_PRIMARY)) {
1616 		ptp->phc_clock_info = efx_phc_clock_info;
1617 		ptp->phc_clock = ptp_clock_register(&ptp->phc_clock_info,
1618 						    &efx->pci_dev->dev);
1619 		if (IS_ERR(ptp->phc_clock)) {
1620 			rc = PTR_ERR(ptp->phc_clock);
1621 			goto fail3;
1622 		} else if (ptp->phc_clock) {
1623 			INIT_WORK(&ptp->pps_work, efx_ptp_pps_worker);
1624 			ptp->pps_workwq = create_singlethread_workqueue("sfc_pps");
1625 			if (!ptp->pps_workwq) {
1626 				rc = -ENOMEM;
1627 				goto fail4;
1628 			}
1629 		}
1630 	}
1631 	ptp->nic_ts_enabled = false;
1632 
1633 	return 0;
1634 fail4:
1635 	ptp_clock_unregister(efx->ptp_data->phc_clock);
1636 
1637 fail3:
1638 	destroy_workqueue(efx->ptp_data->workwq);
1639 
1640 fail2:
1641 	efx_nic_free_buffer(efx, &ptp->start);
1642 
1643 fail1:
1644 	kfree(efx->ptp_data);
1645 	efx->ptp_data = NULL;
1646 
1647 	return rc;
1648 }
1649 
1650 /* Initialise PTP channel.
1651  *
1652  * Setting core_index to zero causes the queue to be initialised and doesn't
1653  * overlap with 'rxq0' because ptp.c doesn't use skb_record_rx_queue.
1654  */
efx_ptp_probe_channel(struct efx_channel * channel)1655 static int efx_ptp_probe_channel(struct efx_channel *channel)
1656 {
1657 	struct efx_nic *efx = channel->efx;
1658 	int rc;
1659 
1660 	channel->irq_moderation_us = 0;
1661 	channel->rx_queue.core_index = 0;
1662 
1663 	rc = efx_ptp_probe(efx, channel);
1664 	/* Failure to probe PTP is not fatal; this channel will just not be
1665 	 * used for anything.
1666 	 * In the case of EPERM, efx_ptp_probe will print its own message (in
1667 	 * efx_ptp_get_attributes()), so we don't need to.
1668 	 */
1669 	if (rc && rc != -EPERM)
1670 		netif_warn(efx, drv, efx->net_dev,
1671 			   "Failed to probe PTP, rc=%d\n", rc);
1672 	return 0;
1673 }
1674 
efx_ptp_remove(struct efx_nic * efx)1675 void efx_ptp_remove(struct efx_nic *efx)
1676 {
1677 	if (!efx->ptp_data)
1678 		return;
1679 
1680 	(void)efx_ptp_disable(efx);
1681 
1682 	cancel_work_sync(&efx->ptp_data->work);
1683 	cancel_delayed_work_sync(&efx->ptp_data->cleanup_work);
1684 	if (efx->ptp_data->pps_workwq)
1685 		cancel_work_sync(&efx->ptp_data->pps_work);
1686 
1687 	skb_queue_purge(&efx->ptp_data->rxq);
1688 	skb_queue_purge(&efx->ptp_data->txq);
1689 
1690 	if (efx->ptp_data->phc_clock) {
1691 		destroy_workqueue(efx->ptp_data->pps_workwq);
1692 		ptp_clock_unregister(efx->ptp_data->phc_clock);
1693 	}
1694 
1695 	destroy_workqueue(efx->ptp_data->workwq);
1696 
1697 	efx_nic_free_buffer(efx, &efx->ptp_data->start);
1698 	kfree(efx->ptp_data);
1699 	efx->ptp_data = NULL;
1700 }
1701 
efx_ptp_remove_channel(struct efx_channel * channel)1702 static void efx_ptp_remove_channel(struct efx_channel *channel)
1703 {
1704 	efx_ptp_remove(channel->efx);
1705 }
1706 
efx_ptp_get_channel_name(struct efx_channel * channel,char * buf,size_t len)1707 static void efx_ptp_get_channel_name(struct efx_channel *channel,
1708 				     char *buf, size_t len)
1709 {
1710 	snprintf(buf, len, "%s-ptp", channel->efx->name);
1711 }
1712 
1713 /* Determine whether this packet should be processed by the PTP module
1714  * or transmitted conventionally.
1715  */
efx_ptp_is_ptp_tx(struct efx_nic * efx,struct sk_buff * skb)1716 bool efx_ptp_is_ptp_tx(struct efx_nic *efx, struct sk_buff *skb)
1717 {
1718 	return efx->ptp_data &&
1719 		efx->ptp_data->enabled &&
1720 		skb->len >= PTP_MIN_LENGTH &&
1721 		skb->len <= MC_CMD_PTP_IN_TRANSMIT_PACKET_MAXNUM &&
1722 		likely(skb->protocol == htons(ETH_P_IP)) &&
1723 		skb_transport_header_was_set(skb) &&
1724 		skb_network_header_len(skb) >= sizeof(struct iphdr) &&
1725 		ip_hdr(skb)->protocol == IPPROTO_UDP &&
1726 		skb_headlen(skb) >=
1727 		skb_transport_offset(skb) + sizeof(struct udphdr) &&
1728 		udp_hdr(skb)->dest == htons(PTP_EVENT_PORT);
1729 }
1730 
1731 /* Receive a PTP packet.  Packets are queued until the arrival of
1732  * the receive timestamp from the MC - this will probably occur after the
1733  * packet arrival because of the processing in the MC.
1734  */
efx_ptp_rx(struct efx_channel * channel,struct sk_buff * skb)1735 static bool efx_ptp_rx(struct efx_channel *channel, struct sk_buff *skb)
1736 {
1737 	struct efx_nic *efx = channel->efx;
1738 	struct efx_ptp_data *ptp = efx->ptp_data;
1739 	struct efx_ptp_match *match = (struct efx_ptp_match *)skb->cb;
1740 	unsigned int version;
1741 	u8 *data;
1742 
1743 	match->expiry = jiffies + msecs_to_jiffies(PKT_EVENT_LIFETIME_MS);
1744 
1745 	/* Correct version? */
1746 	if (ptp->mode == MC_CMD_PTP_MODE_V1) {
1747 		if (!pskb_may_pull(skb, PTP_V1_MIN_LENGTH)) {
1748 			return false;
1749 		}
1750 		data = skb->data;
1751 		version = ntohs(*(__be16 *)&data[PTP_V1_VERSION_OFFSET]);
1752 		if (version != PTP_VERSION_V1) {
1753 			return false;
1754 		}
1755 	} else {
1756 		if (!pskb_may_pull(skb, PTP_V2_MIN_LENGTH)) {
1757 			return false;
1758 		}
1759 		data = skb->data;
1760 		version = data[PTP_V2_VERSION_OFFSET];
1761 		if ((version & PTP_VERSION_V2_MASK) != PTP_VERSION_V2) {
1762 			return false;
1763 		}
1764 	}
1765 
1766 	/* Does this packet require timestamping? */
1767 	if (ntohs(*(__be16 *)&data[PTP_DPORT_OFFSET]) == PTP_EVENT_PORT) {
1768 		match->state = PTP_PACKET_STATE_UNMATCHED;
1769 
1770 		/* We expect the sequence number to be in the same position in
1771 		 * the packet for PTP V1 and V2
1772 		 */
1773 		BUILD_BUG_ON(PTP_V1_SEQUENCE_OFFSET != PTP_V2_SEQUENCE_OFFSET);
1774 		BUILD_BUG_ON(PTP_V1_SEQUENCE_LENGTH != PTP_V2_SEQUENCE_LENGTH);
1775 	} else {
1776 		match->state = PTP_PACKET_STATE_MATCH_UNWANTED;
1777 	}
1778 
1779 	skb_queue_tail(&ptp->rxq, skb);
1780 	queue_work(ptp->workwq, &ptp->work);
1781 
1782 	return true;
1783 }
1784 
1785 /* Transmit a PTP packet.  This has to be transmitted by the MC
1786  * itself, through an MCDI call.  MCDI calls aren't permitted
1787  * in the transmit path so defer the actual transmission to a suitable worker.
1788  */
efx_ptp_tx(struct efx_nic * efx,struct sk_buff * skb)1789 int efx_ptp_tx(struct efx_nic *efx, struct sk_buff *skb)
1790 {
1791 	struct efx_ptp_data *ptp = efx->ptp_data;
1792 
1793 	skb_queue_tail(&ptp->txq, skb);
1794 
1795 	if ((udp_hdr(skb)->dest == htons(PTP_EVENT_PORT)) &&
1796 	    (skb->len <= MC_CMD_PTP_IN_TRANSMIT_PACKET_MAXNUM))
1797 		efx_xmit_hwtstamp_pending(skb);
1798 	queue_work(ptp->workwq, &ptp->work);
1799 
1800 	return NETDEV_TX_OK;
1801 }
1802 
efx_ptp_get_mode(struct efx_nic * efx)1803 int efx_ptp_get_mode(struct efx_nic *efx)
1804 {
1805 	return efx->ptp_data->mode;
1806 }
1807 
efx_ptp_change_mode(struct efx_nic * efx,bool enable_wanted,unsigned int new_mode)1808 int efx_ptp_change_mode(struct efx_nic *efx, bool enable_wanted,
1809 			unsigned int new_mode)
1810 {
1811 	if ((enable_wanted != efx->ptp_data->enabled) ||
1812 	    (enable_wanted && (efx->ptp_data->mode != new_mode))) {
1813 		int rc = 0;
1814 
1815 		if (enable_wanted) {
1816 			/* Change of mode requires disable */
1817 			if (efx->ptp_data->enabled &&
1818 			    (efx->ptp_data->mode != new_mode)) {
1819 				efx->ptp_data->enabled = false;
1820 				rc = efx_ptp_stop(efx);
1821 				if (rc != 0)
1822 					return rc;
1823 			}
1824 
1825 			/* Set new operating mode and establish
1826 			 * baseline synchronisation, which must
1827 			 * succeed.
1828 			 */
1829 			efx->ptp_data->mode = new_mode;
1830 			if (netif_running(efx->net_dev))
1831 				rc = efx_ptp_start(efx);
1832 			if (rc == 0) {
1833 				rc = efx_ptp_synchronize(efx,
1834 							 PTP_SYNC_ATTEMPTS * 2);
1835 				if (rc != 0)
1836 					efx_ptp_stop(efx);
1837 			}
1838 		} else {
1839 			rc = efx_ptp_stop(efx);
1840 		}
1841 
1842 		if (rc != 0)
1843 			return rc;
1844 
1845 		efx->ptp_data->enabled = enable_wanted;
1846 	}
1847 
1848 	return 0;
1849 }
1850 
efx_ptp_ts_init(struct efx_nic * efx,struct kernel_hwtstamp_config * init)1851 static int efx_ptp_ts_init(struct efx_nic *efx, struct kernel_hwtstamp_config *init)
1852 {
1853 	int rc;
1854 
1855 	if ((init->tx_type != HWTSTAMP_TX_OFF) &&
1856 	    (init->tx_type != HWTSTAMP_TX_ON))
1857 		return -ERANGE;
1858 
1859 	rc = efx->type->ptp_set_ts_config(efx, init);
1860 	if (rc)
1861 		return rc;
1862 
1863 	efx->ptp_data->config = *init;
1864 	return 0;
1865 }
1866 
efx_ptp_get_ts_info(struct efx_nic * efx,struct kernel_ethtool_ts_info * ts_info)1867 void efx_ptp_get_ts_info(struct efx_nic *efx, struct kernel_ethtool_ts_info *ts_info)
1868 {
1869 	struct efx_ptp_data *ptp = efx->ptp_data;
1870 	struct efx_nic *primary = efx->primary;
1871 
1872 	ASSERT_RTNL();
1873 
1874 	if (!ptp)
1875 		return;
1876 
1877 	ts_info->so_timestamping |= (SOF_TIMESTAMPING_TX_HARDWARE |
1878 				     SOF_TIMESTAMPING_RX_HARDWARE |
1879 				     SOF_TIMESTAMPING_RAW_HARDWARE);
1880 	/* Check licensed features.  If we don't have the license for TX
1881 	 * timestamps, the NIC will not support them.
1882 	 */
1883 	if (efx_ptp_use_mac_tx_timestamps(efx)) {
1884 		struct efx_ef10_nic_data *nic_data = efx->nic_data;
1885 
1886 		if (!(nic_data->licensed_features &
1887 		      (1 << LICENSED_V3_FEATURES_TX_TIMESTAMPS_LBN)))
1888 			ts_info->so_timestamping &=
1889 				~SOF_TIMESTAMPING_TX_HARDWARE;
1890 	}
1891 	if (primary && primary->ptp_data && primary->ptp_data->phc_clock)
1892 		ts_info->phc_index =
1893 			ptp_clock_index(primary->ptp_data->phc_clock);
1894 	ts_info->tx_types = 1 << HWTSTAMP_TX_OFF | 1 << HWTSTAMP_TX_ON;
1895 	ts_info->rx_filters = ptp->efx->type->hwtstamp_filters;
1896 }
1897 
efx_ptp_set_ts_config(struct efx_nic * efx,struct kernel_hwtstamp_config * config,struct netlink_ext_ack __always_unused * extack)1898 int efx_ptp_set_ts_config(struct efx_nic *efx,
1899 			  struct kernel_hwtstamp_config *config,
1900 			  struct netlink_ext_ack __always_unused *extack)
1901 {
1902 	/* Not a PTP enabled port */
1903 	if (!efx->ptp_data)
1904 		return -EOPNOTSUPP;
1905 
1906 	return efx_ptp_ts_init(efx, config);
1907 }
1908 
efx_ptp_get_ts_config(struct efx_nic * efx,struct kernel_hwtstamp_config * config)1909 int efx_ptp_get_ts_config(struct efx_nic *efx,
1910 			  struct kernel_hwtstamp_config *config)
1911 {
1912 	/* Not a PTP enabled port */
1913 	if (!efx->ptp_data)
1914 		return -EOPNOTSUPP;
1915 	*config = efx->ptp_data->config;
1916 	return 0;
1917 }
1918 
ptp_event_failure(struct efx_nic * efx,int expected_frag_len)1919 static void ptp_event_failure(struct efx_nic *efx, int expected_frag_len)
1920 {
1921 	struct efx_ptp_data *ptp = efx->ptp_data;
1922 
1923 	netif_err(efx, hw, efx->net_dev,
1924 		"PTP unexpected event length: got %d expected %d\n",
1925 		ptp->evt_frag_idx, expected_frag_len);
1926 	ptp->reset_required = true;
1927 	queue_work(ptp->workwq, &ptp->work);
1928 }
1929 
ptp_event_fault(struct efx_nic * efx,struct efx_ptp_data * ptp)1930 static void ptp_event_fault(struct efx_nic *efx, struct efx_ptp_data *ptp)
1931 {
1932 	int code = EFX_QWORD_FIELD(ptp->evt_frags[0], MCDI_EVENT_DATA);
1933 	if (ptp->evt_frag_idx != 1) {
1934 		ptp_event_failure(efx, 1);
1935 		return;
1936 	}
1937 
1938 	netif_err(efx, hw, efx->net_dev, "PTP error %d\n", code);
1939 }
1940 
ptp_event_pps(struct efx_nic * efx,struct efx_ptp_data * ptp)1941 static void ptp_event_pps(struct efx_nic *efx, struct efx_ptp_data *ptp)
1942 {
1943 	if (ptp->nic_ts_enabled)
1944 		queue_work(ptp->pps_workwq, &ptp->pps_work);
1945 }
1946 
efx_ptp_event(struct efx_nic * efx,efx_qword_t * ev)1947 void efx_ptp_event(struct efx_nic *efx, efx_qword_t *ev)
1948 {
1949 	struct efx_ptp_data *ptp = efx->ptp_data;
1950 	int code = EFX_QWORD_FIELD(*ev, MCDI_EVENT_CODE);
1951 
1952 	if (!ptp) {
1953 		if (!efx->ptp_warned) {
1954 			netif_warn(efx, drv, efx->net_dev,
1955 				   "Received PTP event but PTP not set up\n");
1956 			efx->ptp_warned = true;
1957 		}
1958 		return;
1959 	}
1960 
1961 	if (!ptp->enabled)
1962 		return;
1963 
1964 	if (ptp->evt_frag_idx == 0) {
1965 		ptp->evt_code = code;
1966 	} else if (ptp->evt_code != code) {
1967 		netif_err(efx, hw, efx->net_dev,
1968 			  "PTP out of sequence event %d\n", code);
1969 		ptp->evt_frag_idx = 0;
1970 	}
1971 
1972 	ptp->evt_frags[ptp->evt_frag_idx++] = *ev;
1973 	if (!MCDI_EVENT_FIELD(*ev, CONT)) {
1974 		/* Process resulting event */
1975 		switch (code) {
1976 		case MCDI_EVENT_CODE_PTP_FAULT:
1977 			ptp_event_fault(efx, ptp);
1978 			break;
1979 		case MCDI_EVENT_CODE_PTP_PPS:
1980 			ptp_event_pps(efx, ptp);
1981 			break;
1982 		default:
1983 			netif_err(efx, hw, efx->net_dev,
1984 				  "PTP unknown event %d\n", code);
1985 			break;
1986 		}
1987 		ptp->evt_frag_idx = 0;
1988 	} else if (MAX_EVENT_FRAGS == ptp->evt_frag_idx) {
1989 		netif_err(efx, hw, efx->net_dev,
1990 			  "PTP too many event fragments\n");
1991 		ptp->evt_frag_idx = 0;
1992 	}
1993 }
1994 
efx_time_sync_event(struct efx_channel * channel,efx_qword_t * ev)1995 void efx_time_sync_event(struct efx_channel *channel, efx_qword_t *ev)
1996 {
1997 	struct efx_nic *efx = channel->efx;
1998 	struct efx_ptp_data *ptp = efx->ptp_data;
1999 
2000 	/* When extracting the sync timestamp minor value, we should discard
2001 	 * the least significant two bits. These are not required in order
2002 	 * to reconstruct full-range timestamps and they are optionally used
2003 	 * to report status depending on the options supplied when subscribing
2004 	 * for sync events.
2005 	 */
2006 	channel->sync_timestamp_major = MCDI_EVENT_FIELD(*ev, PTP_TIME_MAJOR);
2007 	channel->sync_timestamp_minor =
2008 		(MCDI_EVENT_FIELD(*ev, PTP_TIME_MINOR_MS_8BITS) & 0xFC)
2009 			<< ptp->nic_time.sync_event_minor_shift;
2010 
2011 	/* if sync events have been disabled then we want to silently ignore
2012 	 * this event, so throw away result.
2013 	 */
2014 	(void) cmpxchg(&channel->sync_events_state, SYNC_EVENTS_REQUESTED,
2015 		       SYNC_EVENTS_VALID);
2016 }
2017 
efx_rx_buf_timestamp_minor(struct efx_nic * efx,const u8 * eh)2018 static inline u32 efx_rx_buf_timestamp_minor(struct efx_nic *efx, const u8 *eh)
2019 {
2020 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
2021 	return __le32_to_cpup((const __le32 *)(eh + efx->rx_packet_ts_offset));
2022 #else
2023 	const u8 *data = eh + efx->rx_packet_ts_offset;
2024 	return (u32)data[0]       |
2025 	       (u32)data[1] << 8  |
2026 	       (u32)data[2] << 16 |
2027 	       (u32)data[3] << 24;
2028 #endif
2029 }
2030 
__efx_rx_skb_attach_timestamp(struct efx_channel * channel,struct sk_buff * skb)2031 void __efx_rx_skb_attach_timestamp(struct efx_channel *channel,
2032 				   struct sk_buff *skb)
2033 {
2034 	struct efx_nic *efx = channel->efx;
2035 	struct efx_ptp_data *ptp = efx->ptp_data;
2036 	u32 pkt_timestamp_major, pkt_timestamp_minor;
2037 	u32 diff, carry;
2038 	struct skb_shared_hwtstamps *timestamps;
2039 
2040 	if (channel->sync_events_state != SYNC_EVENTS_VALID)
2041 		return;
2042 
2043 	pkt_timestamp_minor = efx_rx_buf_timestamp_minor(efx, skb_mac_header(skb));
2044 
2045 	/* get the difference between the packet and sync timestamps,
2046 	 * modulo one second
2047 	 */
2048 	diff = pkt_timestamp_minor - channel->sync_timestamp_minor;
2049 	if (pkt_timestamp_minor < channel->sync_timestamp_minor)
2050 		diff += ptp->nic_time.minor_max;
2051 
2052 	/* do we roll over a second boundary and need to carry the one? */
2053 	carry = (channel->sync_timestamp_minor >= ptp->nic_time.minor_max - diff) ?
2054 		1 : 0;
2055 
2056 	if (diff <= ptp->nic_time.sync_event_diff_max) {
2057 		/* packet is ahead of the sync event by a quarter of a second or
2058 		 * less (allowing for fuzz)
2059 		 */
2060 		pkt_timestamp_major = channel->sync_timestamp_major + carry;
2061 	} else if (diff >= ptp->nic_time.sync_event_diff_min) {
2062 		/* packet is behind the sync event but within the fuzz factor.
2063 		 * This means the RX packet and sync event crossed as they were
2064 		 * placed on the event queue, which can sometimes happen.
2065 		 */
2066 		pkt_timestamp_major = channel->sync_timestamp_major - 1 + carry;
2067 	} else {
2068 		/* it's outside tolerance in both directions. this might be
2069 		 * indicative of us missing sync events for some reason, so
2070 		 * we'll call it an error rather than risk giving a bogus
2071 		 * timestamp.
2072 		 */
2073 		netif_vdbg(efx, drv, efx->net_dev,
2074 			  "packet timestamp %x too far from sync event %x:%x\n",
2075 			  pkt_timestamp_minor, channel->sync_timestamp_major,
2076 			  channel->sync_timestamp_minor);
2077 		return;
2078 	}
2079 
2080 	/* attach the timestamps to the skb */
2081 	timestamps = skb_hwtstamps(skb);
2082 	timestamps->hwtstamp =
2083 		ptp->nic_to_kernel_time(pkt_timestamp_major,
2084 					pkt_timestamp_minor,
2085 					ptp->ts_corrections.general_rx);
2086 }
2087 
efx_phc_adjfine(struct ptp_clock_info * ptp,long scaled_ppm)2088 static int efx_phc_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
2089 {
2090 	struct efx_ptp_data *ptp_data = container_of(ptp,
2091 						     struct efx_ptp_data,
2092 						     phc_clock_info);
2093 	s32 delta = scaled_ppm_to_ppb(scaled_ppm);
2094 	struct efx_nic *efx = ptp_data->efx;
2095 	MCDI_DECLARE_BUF(inadj, MC_CMD_PTP_IN_ADJUST_LEN);
2096 	s64 adjustment_ns;
2097 	int rc;
2098 
2099 	if (delta > MAX_PPB)
2100 		delta = MAX_PPB;
2101 	else if (delta < -MAX_PPB)
2102 		delta = -MAX_PPB;
2103 
2104 	/* Convert ppb to fixed point ns taking care to round correctly. */
2105 	adjustment_ns = ((s64)delta * PPB_SCALE_WORD +
2106 			 (1 << (ptp_data->adjfreq_ppb_shift - 1))) >>
2107 			ptp_data->adjfreq_ppb_shift;
2108 
2109 	MCDI_SET_DWORD(inadj, PTP_IN_OP, MC_CMD_PTP_OP_ADJUST);
2110 	MCDI_SET_DWORD(inadj, PTP_IN_PERIPH_ID, 0);
2111 	MCDI_SET_QWORD(inadj, PTP_IN_ADJUST_FREQ, adjustment_ns);
2112 	MCDI_SET_DWORD(inadj, PTP_IN_ADJUST_SECONDS, 0);
2113 	MCDI_SET_DWORD(inadj, PTP_IN_ADJUST_NANOSECONDS, 0);
2114 	rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inadj, sizeof(inadj),
2115 			  NULL, 0, NULL);
2116 	if (rc != 0)
2117 		return rc;
2118 
2119 	ptp_data->current_adjfreq = adjustment_ns;
2120 	return 0;
2121 }
2122 
efx_phc_adjtime(struct ptp_clock_info * ptp,s64 delta)2123 static int efx_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
2124 {
2125 	u32 nic_major, nic_minor;
2126 	struct efx_ptp_data *ptp_data = container_of(ptp,
2127 						     struct efx_ptp_data,
2128 						     phc_clock_info);
2129 	struct efx_nic *efx = ptp_data->efx;
2130 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_ADJUST_LEN);
2131 
2132 	efx->ptp_data->ns_to_nic_time(delta, &nic_major, &nic_minor);
2133 
2134 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_ADJUST);
2135 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
2136 	MCDI_SET_QWORD(inbuf, PTP_IN_ADJUST_FREQ, ptp_data->current_adjfreq);
2137 	MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_MAJOR, nic_major);
2138 	MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_MINOR, nic_minor);
2139 	return efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
2140 			    NULL, 0, NULL);
2141 }
2142 
efx_phc_gettime(struct ptp_clock_info * ptp,struct timespec64 * ts)2143 static int efx_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
2144 {
2145 	struct efx_ptp_data *ptp_data = container_of(ptp,
2146 						     struct efx_ptp_data,
2147 						     phc_clock_info);
2148 	struct efx_nic *efx = ptp_data->efx;
2149 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_READ_NIC_TIME_LEN);
2150 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_READ_NIC_TIME_LEN);
2151 	int rc;
2152 	ktime_t kt;
2153 
2154 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_READ_NIC_TIME);
2155 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
2156 
2157 	rc = efx_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
2158 			  outbuf, sizeof(outbuf), NULL);
2159 	if (rc != 0)
2160 		return rc;
2161 
2162 	kt = ptp_data->nic_to_kernel_time(
2163 		MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_MAJOR),
2164 		MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_MINOR), 0);
2165 	*ts = ktime_to_timespec64(kt);
2166 	return 0;
2167 }
2168 
efx_phc_settime(struct ptp_clock_info * ptp,const struct timespec64 * e_ts)2169 static int efx_phc_settime(struct ptp_clock_info *ptp,
2170 			   const struct timespec64 *e_ts)
2171 {
2172 	/* Get the current NIC time, efx_phc_gettime.
2173 	 * Subtract from the desired time to get the offset
2174 	 * call efx_phc_adjtime with the offset
2175 	 */
2176 	int rc;
2177 	struct timespec64 time_now;
2178 	struct timespec64 delta;
2179 
2180 	rc = efx_phc_gettime(ptp, &time_now);
2181 	if (rc != 0)
2182 		return rc;
2183 
2184 	delta = timespec64_sub(*e_ts, time_now);
2185 
2186 	rc = efx_phc_adjtime(ptp, timespec64_to_ns(&delta));
2187 	if (rc != 0)
2188 		return rc;
2189 
2190 	return 0;
2191 }
2192 
efx_phc_enable(struct ptp_clock_info * ptp,struct ptp_clock_request * request,int enable)2193 static int efx_phc_enable(struct ptp_clock_info *ptp,
2194 			  struct ptp_clock_request *request,
2195 			  int enable)
2196 {
2197 	struct efx_ptp_data *ptp_data = container_of(ptp,
2198 						     struct efx_ptp_data,
2199 						     phc_clock_info);
2200 	if (request->type != PTP_CLK_REQ_PPS)
2201 		return -EOPNOTSUPP;
2202 
2203 	ptp_data->nic_ts_enabled = !!enable;
2204 	return 0;
2205 }
2206 
2207 static const struct efx_channel_type efx_ptp_channel_type = {
2208 	.handle_no_channel	= efx_ptp_handle_no_channel,
2209 	.pre_probe		= efx_ptp_probe_channel,
2210 	.post_remove		= efx_ptp_remove_channel,
2211 	.get_name		= efx_ptp_get_channel_name,
2212 	.copy                   = efx_copy_channel,
2213 	.receive_skb		= efx_ptp_rx,
2214 	.want_txqs		= efx_ptp_want_txqs,
2215 	.keep_eventq		= false,
2216 };
2217 
efx_ptp_defer_probe_with_channel(struct efx_nic * efx)2218 void efx_ptp_defer_probe_with_channel(struct efx_nic *efx)
2219 {
2220 	/* Check whether PTP is implemented on this NIC.  The DISABLE
2221 	 * operation will succeed if and only if it is implemented.
2222 	 */
2223 	if (efx_ptp_disable(efx) == 0)
2224 		efx->extra_channel_type[EFX_EXTRA_CHANNEL_PTP] =
2225 			&efx_ptp_channel_type;
2226 }
2227 
efx_ptp_start_datapath(struct efx_nic * efx)2228 void efx_ptp_start_datapath(struct efx_nic *efx)
2229 {
2230 	if (efx_ptp_restart(efx))
2231 		netif_err(efx, drv, efx->net_dev, "Failed to restart PTP.\n");
2232 	/* re-enable timestamping if it was previously enabled */
2233 	if (efx->type->ptp_set_ts_sync_events)
2234 		efx->type->ptp_set_ts_sync_events(efx, true, true);
2235 }
2236 
efx_ptp_stop_datapath(struct efx_nic * efx)2237 void efx_ptp_stop_datapath(struct efx_nic *efx)
2238 {
2239 	/* temporarily disable timestamping */
2240 	if (efx->type->ptp_set_ts_sync_events)
2241 		efx->type->ptp_set_ts_sync_events(efx, false, true);
2242 	efx_ptp_stop(efx);
2243 }
2244