xref: /linux/drivers/net/ethernet/sfc/siena/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/ktime.h>
37 #include <linux/module.h>
38 #include <linux/pps_kernel.h>
39 #include <linux/ptp_clock_kernel.h>
40 #include "net_driver.h"
41 #include "efx.h"
42 #include "mcdi.h"
43 #include "mcdi_pcol.h"
44 #include "io.h"
45 #include "farch_regs.h"
46 #include "tx.h"
47 #include "nic.h" /* indirectly includes ptp.h */
48 
49 /* Maximum number of events expected to make up a PTP event */
50 #define	MAX_EVENT_FRAGS			3
51 
52 /* Maximum delay, ms, to begin synchronisation */
53 #define	MAX_SYNCHRONISE_WAIT_MS		2
54 
55 /* How long, at most, to spend synchronising */
56 #define	SYNCHRONISE_PERIOD_NS		250000
57 
58 /* How often to update the shared memory time */
59 #define	SYNCHRONISATION_GRANULARITY_NS	200
60 
61 /* Minimum permitted length of a (corrected) synchronisation time */
62 #define	DEFAULT_MIN_SYNCHRONISATION_NS	120
63 
64 /* Maximum permitted length of a (corrected) synchronisation time */
65 #define	MAX_SYNCHRONISATION_NS		1000
66 
67 /* How many (MC) receive events that can be queued */
68 #define	MAX_RECEIVE_EVENTS		8
69 
70 /* Length of (modified) moving average. */
71 #define	AVERAGE_LENGTH			16
72 
73 /* How long an unmatched event or packet can be held */
74 #define PKT_EVENT_LIFETIME_MS		10
75 
76 /* Offsets into PTP packet for identification.  These offsets are from the
77  * start of the IP header, not the MAC header.  Note that neither PTP V1 nor
78  * PTP V2 permit the use of IPV4 options.
79  */
80 #define PTP_DPORT_OFFSET	22
81 
82 #define PTP_V1_VERSION_LENGTH	2
83 #define PTP_V1_VERSION_OFFSET	28
84 
85 #define PTP_V1_UUID_LENGTH	6
86 #define PTP_V1_UUID_OFFSET	50
87 
88 #define PTP_V1_SEQUENCE_LENGTH	2
89 #define PTP_V1_SEQUENCE_OFFSET	58
90 
91 /* The minimum length of a PTP V1 packet for offsets, etc. to be valid:
92  * includes IP header.
93  */
94 #define	PTP_V1_MIN_LENGTH	64
95 
96 #define PTP_V2_VERSION_LENGTH	1
97 #define PTP_V2_VERSION_OFFSET	29
98 
99 #define PTP_V2_UUID_LENGTH	8
100 #define PTP_V2_UUID_OFFSET	48
101 
102 /* Although PTP V2 UUIDs are comprised a ClockIdentity (8) and PortNumber (2),
103  * the MC only captures the last six bytes of the clock identity. These values
104  * reflect those, not the ones used in the standard.  The standard permits
105  * mapping of V1 UUIDs to V2 UUIDs with these same values.
106  */
107 #define PTP_V2_MC_UUID_LENGTH	6
108 #define PTP_V2_MC_UUID_OFFSET	50
109 
110 #define PTP_V2_SEQUENCE_LENGTH	2
111 #define PTP_V2_SEQUENCE_OFFSET	58
112 
113 /* The minimum length of a PTP V2 packet for offsets, etc. to be valid:
114  * includes IP header.
115  */
116 #define	PTP_V2_MIN_LENGTH	63
117 
118 #define	PTP_MIN_LENGTH		63
119 
120 #define PTP_ADDRESS		0xe0000181	/* 224.0.1.129 */
121 #define PTP_EVENT_PORT		319
122 #define PTP_GENERAL_PORT	320
123 
124 /* Annoyingly the format of the version numbers are different between
125  * versions 1 and 2 so it isn't possible to simply look for 1 or 2.
126  */
127 #define	PTP_VERSION_V1		1
128 
129 #define	PTP_VERSION_V2		2
130 #define	PTP_VERSION_V2_MASK	0x0f
131 
132 enum ptp_packet_state {
133 	PTP_PACKET_STATE_UNMATCHED = 0,
134 	PTP_PACKET_STATE_MATCHED,
135 	PTP_PACKET_STATE_TIMED_OUT,
136 	PTP_PACKET_STATE_MATCH_UNWANTED
137 };
138 
139 /* NIC synchronised with single word of time only comprising
140  * partial seconds and full nanoseconds: 10^9 ~ 2^30 so 2 bits for seconds.
141  */
142 #define	MC_NANOSECOND_BITS	30
143 #define	MC_NANOSECOND_MASK	((1 << MC_NANOSECOND_BITS) - 1)
144 #define	MC_SECOND_MASK		((1 << (32 - MC_NANOSECOND_BITS)) - 1)
145 
146 /* Maximum parts-per-billion adjustment that is acceptable */
147 #define MAX_PPB			1000000
148 
149 /* Precalculate scale word to avoid long long division at runtime */
150 /* This is equivalent to 2^66 / 10^9. */
151 #define PPB_SCALE_WORD  ((1LL << (57)) / 1953125LL)
152 
153 /* How much to shift down after scaling to convert to FP40 */
154 #define PPB_SHIFT_FP40		26
155 /* ... and FP44. */
156 #define PPB_SHIFT_FP44		22
157 
158 #define PTP_SYNC_ATTEMPTS	4
159 
160 /**
161  * struct efx_ptp_match - Matching structure, stored in sk_buff's cb area.
162  * @words: UUID and (partial) sequence number
163  * @expiry: Time after which the packet should be delivered irrespective of
164  *            event arrival.
165  * @state: The state of the packet - whether it is ready for processing or
166  *         whether that is of no interest.
167  */
168 struct efx_ptp_match {
169 	u32 words[DIV_ROUND_UP(PTP_V1_UUID_LENGTH, 4)];
170 	unsigned long expiry;
171 	enum ptp_packet_state state;
172 };
173 
174 /**
175  * struct efx_ptp_event_rx - A PTP receive event (from MC)
176  * @link: list of events
177  * @seq0: First part of (PTP) UUID
178  * @seq1: Second part of (PTP) UUID and sequence number
179  * @hwtimestamp: Event timestamp
180  * @expiry: Time which the packet arrived
181  */
182 struct efx_ptp_event_rx {
183 	struct list_head link;
184 	u32 seq0;
185 	u32 seq1;
186 	ktime_t hwtimestamp;
187 	unsigned long expiry;
188 };
189 
190 /**
191  * struct efx_ptp_timeset - Synchronisation between host and MC
192  * @host_start: Host time immediately before hardware timestamp taken
193  * @major: Hardware timestamp, major
194  * @minor: Hardware timestamp, minor
195  * @host_end: Host time immediately after hardware timestamp taken
196  * @wait: Number of NIC clock ticks between hardware timestamp being read and
197  *          host end time being seen
198  * @window: Difference of host_end and host_start
199  * @valid: Whether this timeset is valid
200  */
201 struct efx_ptp_timeset {
202 	u32 host_start;
203 	u32 major;
204 	u32 minor;
205 	u32 host_end;
206 	u32 wait;
207 	u32 window;	/* Derived: end - start, allowing for wrap */
208 };
209 
210 /**
211  * struct efx_ptp_data - Precision Time Protocol (PTP) state
212  * @efx: The NIC context
213  * @channel: The PTP channel (Siena only)
214  * @rx_ts_inline: Flag for whether RX timestamps are inline (else they are
215  *	separate events)
216  * @rxq: Receive SKB queue (awaiting timestamps)
217  * @txq: Transmit SKB queue
218  * @evt_list: List of MC receive events awaiting packets
219  * @evt_free_list: List of free events
220  * @evt_lock: Lock for manipulating evt_list and evt_free_list
221  * @rx_evts: Instantiated events (on evt_list and evt_free_list)
222  * @workwq: Work queue for processing pending PTP operations
223  * @work: Work task
224  * @reset_required: A serious error has occurred and the PTP task needs to be
225  *                  reset (disable, enable).
226  * @rxfilter_event: Receive filter when operating
227  * @rxfilter_general: Receive filter when operating
228  * @rxfilter_installed: Receive filter installed
229  * @config: Current timestamp configuration
230  * @enabled: PTP operation enabled
231  * @mode: Mode in which PTP operating (PTP version)
232  * @ns_to_nic_time: Function to convert from scalar nanoseconds to NIC time
233  * @nic_to_kernel_time: Function to convert from NIC to kernel time
234  * @nic_time: contains time details
235  * @nic_time.minor_max: Wrap point for NIC minor times
236  * @nic_time.sync_event_diff_min: Minimum acceptable difference between time
237  * in packet prefix and last MCDI time sync event i.e. how much earlier than
238  * the last sync event time a packet timestamp can be.
239  * @nic_time.sync_event_diff_max: Maximum acceptable difference between time
240  * in packet prefix and last MCDI time sync event i.e. how much later than
241  * the last sync event time a packet timestamp can be.
242  * @nic_time.sync_event_minor_shift: Shift required to make minor time from
243  * field in MCDI time sync event.
244  * @min_synchronisation_ns: Minimum acceptable corrected sync window
245  * @capabilities: Capabilities flags from the NIC
246  * @ts_corrections: contains corrections details
247  * @ts_corrections.ptp_tx: Required driver correction of PTP packet transmit
248  *                         timestamps
249  * @ts_corrections.ptp_rx: Required driver correction of PTP packet receive
250  *                         timestamps
251  * @ts_corrections.pps_out: PPS output error (information only)
252  * @ts_corrections.pps_in: Required driver correction of PPS input timestamps
253  * @ts_corrections.general_tx: Required driver correction of general packet
254  *                             transmit timestamps
255  * @ts_corrections.general_rx: Required driver correction of general packet
256  *                             receive timestamps
257  * @evt_frags: Partly assembled PTP events
258  * @evt_frag_idx: Current fragment number
259  * @evt_code: Last event code
260  * @start: Address at which MC indicates ready for synchronisation
261  * @host_time_pps: Host time at last PPS
262  * @adjfreq_ppb_shift: Shift required to convert scaled parts-per-billion
263  * frequency adjustment into a fixed point fractional nanosecond format.
264  * @current_adjfreq: Current ppb adjustment.
265  * @phc_clock: Pointer to registered phc device (if primary function)
266  * @phc_clock_info: Registration structure for phc device
267  * @pps_work: pps work task for handling pps events
268  * @pps_workwq: pps work queue
269  * @nic_ts_enabled: Flag indicating if NIC generated TS events are handled
270  * @txbuf: Buffer for use when transmitting (PTP) packets to MC (avoids
271  *         allocations in main data path).
272  * @good_syncs: Number of successful synchronisations.
273  * @fast_syncs: Number of synchronisations requiring short delay
274  * @bad_syncs: Number of failed synchronisations.
275  * @sync_timeouts: Number of synchronisation timeouts
276  * @no_time_syncs: Number of synchronisations with no good times.
277  * @invalid_sync_windows: Number of sync windows with bad durations.
278  * @undersize_sync_windows: Number of corrected sync windows that are too small
279  * @oversize_sync_windows: Number of corrected sync windows that are too large
280  * @rx_no_timestamp: Number of packets received without a timestamp.
281  * @timeset: Last set of synchronisation statistics.
282  * @xmit_skb: Transmit SKB function.
283  */
284 struct efx_ptp_data {
285 	struct efx_nic *efx;
286 	struct efx_channel *channel;
287 	bool rx_ts_inline;
288 	struct sk_buff_head rxq;
289 	struct sk_buff_head txq;
290 	struct list_head evt_list;
291 	struct list_head evt_free_list;
292 	spinlock_t evt_lock;
293 	struct efx_ptp_event_rx rx_evts[MAX_RECEIVE_EVENTS];
294 	struct workqueue_struct *workwq;
295 	struct work_struct work;
296 	bool reset_required;
297 	u32 rxfilter_event;
298 	u32 rxfilter_general;
299 	bool rxfilter_installed;
300 	struct kernel_hwtstamp_config config;
301 	bool enabled;
302 	unsigned int mode;
303 	void (*ns_to_nic_time)(s64 ns, u32 *nic_major, u32 *nic_minor);
304 	ktime_t (*nic_to_kernel_time)(u32 nic_major, u32 nic_minor,
305 				      s32 correction);
306 	struct {
307 		u32 minor_max;
308 		u32 sync_event_diff_min;
309 		u32 sync_event_diff_max;
310 		unsigned int sync_event_minor_shift;
311 	} nic_time;
312 	unsigned int min_synchronisation_ns;
313 	unsigned int capabilities;
314 	struct {
315 		s32 ptp_tx;
316 		s32 ptp_rx;
317 		s32 pps_out;
318 		s32 pps_in;
319 		s32 general_tx;
320 		s32 general_rx;
321 	} ts_corrections;
322 	efx_qword_t evt_frags[MAX_EVENT_FRAGS];
323 	int evt_frag_idx;
324 	int evt_code;
325 	struct efx_buffer start;
326 	struct pps_event_time host_time_pps;
327 	unsigned int adjfreq_ppb_shift;
328 	s64 current_adjfreq;
329 	struct ptp_clock *phc_clock;
330 	struct ptp_clock_info phc_clock_info;
331 	struct work_struct pps_work;
332 	struct workqueue_struct *pps_workwq;
333 	bool nic_ts_enabled;
334 	efx_dword_t txbuf[MCDI_TX_BUF_LEN(MC_CMD_PTP_IN_TRANSMIT_LENMAX)];
335 
336 	unsigned int good_syncs;
337 	unsigned int fast_syncs;
338 	unsigned int bad_syncs;
339 	unsigned int sync_timeouts;
340 	unsigned int no_time_syncs;
341 	unsigned int invalid_sync_windows;
342 	unsigned int undersize_sync_windows;
343 	unsigned int oversize_sync_windows;
344 	unsigned int rx_no_timestamp;
345 	struct efx_ptp_timeset
346 	timeset[MC_CMD_PTP_OUT_SYNCHRONIZE_TIMESET_MAXNUM];
347 	void (*xmit_skb)(struct efx_nic *efx, struct sk_buff *skb);
348 };
349 
350 static int efx_phc_adjfine(struct ptp_clock_info *ptp, long scaled_ppm);
351 static int efx_phc_adjtime(struct ptp_clock_info *ptp, s64 delta);
352 static int efx_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts);
353 static int efx_phc_settime(struct ptp_clock_info *ptp,
354 			   const struct timespec64 *e_ts);
355 static int efx_phc_enable(struct ptp_clock_info *ptp,
356 			  struct ptp_clock_request *request, int on);
357 
efx_siena_ptp_use_mac_tx_timestamps(struct efx_nic * efx)358 bool efx_siena_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_siena_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_siena_ptp_describe_stats(struct efx_nic * efx,u8 * strings)396 size_t efx_siena_ptp_describe_stats(struct efx_nic *efx, u8 *strings)
397 {
398 	if (!efx->ptp_data)
399 		return 0;
400 
401 	return efx_siena_describe_stats(efx_ptp_stat_desc, PTP_STAT_COUNT,
402 					efx_ptp_stat_mask, strings);
403 }
404 
efx_siena_ptp_update_stats(struct efx_nic * efx,u64 * stats)405 size_t efx_siena_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_siena_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_siena_update_stats(efx_ptp_stat_desc, PTP_STAT_COUNT,
434 			       efx_ptp_stat_mask,
435 			       stats, _MCDI_PTR(outbuf, 0), false);
436 
437 	return PTP_STAT_COUNT;
438 }
439 
440 /* For Siena platforms NIC time is s and ns */
efx_ptp_ns_to_s_ns(s64 ns,u32 * nic_major,u32 * nic_minor)441 static void efx_ptp_ns_to_s_ns(s64 ns, u32 *nic_major, u32 *nic_minor)
442 {
443 	struct timespec64 ts = ns_to_timespec64(ns);
444 	*nic_major = (u32)ts.tv_sec;
445 	*nic_minor = ts.tv_nsec;
446 }
447 
efx_ptp_s_ns_to_ktime_correction(u32 nic_major,u32 nic_minor,s32 correction)448 static ktime_t efx_ptp_s_ns_to_ktime_correction(u32 nic_major, u32 nic_minor,
449 						s32 correction)
450 {
451 	ktime_t kt = ktime_set(nic_major, nic_minor);
452 	if (correction >= 0)
453 		kt = ktime_add_ns(kt, (u64)correction);
454 	else
455 		kt = ktime_sub_ns(kt, (u64)-correction);
456 	return kt;
457 }
458 
459 /* To convert from s27 format to ns we multiply then divide by a power of 2.
460  * For the conversion from ns to s27, the operation is also converted to a
461  * multiply and shift.
462  */
463 #define S27_TO_NS_SHIFT	(27)
464 #define NS_TO_S27_MULT	(((1ULL << 63) + NSEC_PER_SEC / 2) / NSEC_PER_SEC)
465 #define NS_TO_S27_SHIFT	(63 - S27_TO_NS_SHIFT)
466 #define S27_MINOR_MAX	(1 << S27_TO_NS_SHIFT)
467 
468 /* For Huntington platforms NIC time is in seconds and fractions of a second
469  * where the minor register only uses 27 bits in units of 2^-27s.
470  */
efx_ptp_ns_to_s27(s64 ns,u32 * nic_major,u32 * nic_minor)471 static void efx_ptp_ns_to_s27(s64 ns, u32 *nic_major, u32 *nic_minor)
472 {
473 	struct timespec64 ts = ns_to_timespec64(ns);
474 	u32 maj = (u32)ts.tv_sec;
475 	u32 min = (u32)(((u64)ts.tv_nsec * NS_TO_S27_MULT +
476 			 (1ULL << (NS_TO_S27_SHIFT - 1))) >> NS_TO_S27_SHIFT);
477 
478 	/* The conversion can result in the minor value exceeding the maximum.
479 	 * In this case, round up to the next second.
480 	 */
481 	if (min >= S27_MINOR_MAX) {
482 		min -= S27_MINOR_MAX;
483 		maj++;
484 	}
485 
486 	*nic_major = maj;
487 	*nic_minor = min;
488 }
489 
efx_ptp_s27_to_ktime(u32 nic_major,u32 nic_minor)490 static inline ktime_t efx_ptp_s27_to_ktime(u32 nic_major, u32 nic_minor)
491 {
492 	u32 ns = (u32)(((u64)nic_minor * NSEC_PER_SEC +
493 			(1ULL << (S27_TO_NS_SHIFT - 1))) >> S27_TO_NS_SHIFT);
494 	return ktime_set(nic_major, ns);
495 }
496 
efx_ptp_s27_to_ktime_correction(u32 nic_major,u32 nic_minor,s32 correction)497 static ktime_t efx_ptp_s27_to_ktime_correction(u32 nic_major, u32 nic_minor,
498 					       s32 correction)
499 {
500 	/* Apply the correction and deal with carry */
501 	nic_minor += correction;
502 	if ((s32)nic_minor < 0) {
503 		nic_minor += S27_MINOR_MAX;
504 		nic_major--;
505 	} else if (nic_minor >= S27_MINOR_MAX) {
506 		nic_minor -= S27_MINOR_MAX;
507 		nic_major++;
508 	}
509 
510 	return efx_ptp_s27_to_ktime(nic_major, nic_minor);
511 }
512 
513 /* For Medford2 platforms the time is in seconds and quarter nanoseconds. */
efx_ptp_ns_to_s_qns(s64 ns,u32 * nic_major,u32 * nic_minor)514 static void efx_ptp_ns_to_s_qns(s64 ns, u32 *nic_major, u32 *nic_minor)
515 {
516 	struct timespec64 ts = ns_to_timespec64(ns);
517 
518 	*nic_major = (u32)ts.tv_sec;
519 	*nic_minor = ts.tv_nsec * 4;
520 }
521 
efx_ptp_s_qns_to_ktime_correction(u32 nic_major,u32 nic_minor,s32 correction)522 static ktime_t efx_ptp_s_qns_to_ktime_correction(u32 nic_major, u32 nic_minor,
523 						 s32 correction)
524 {
525 	ktime_t kt;
526 
527 	nic_minor = DIV_ROUND_CLOSEST(nic_minor, 4);
528 	correction = DIV_ROUND_CLOSEST(correction, 4);
529 
530 	kt = ktime_set(nic_major, nic_minor);
531 
532 	if (correction >= 0)
533 		kt = ktime_add_ns(kt, (u64)correction);
534 	else
535 		kt = ktime_sub_ns(kt, (u64)-correction);
536 	return kt;
537 }
538 
efx_siena_ptp_channel(struct efx_nic * efx)539 struct efx_channel *efx_siena_ptp_channel(struct efx_nic *efx)
540 {
541 	return efx->ptp_data ? efx->ptp_data->channel : NULL;
542 }
543 
last_sync_timestamp_major(struct efx_nic * efx)544 static u32 last_sync_timestamp_major(struct efx_nic *efx)
545 {
546 	struct efx_channel *channel = efx_siena_ptp_channel(efx);
547 	u32 major = 0;
548 
549 	if (channel)
550 		major = channel->sync_timestamp_major;
551 	return major;
552 }
553 
554 /* The 8000 series and later can provide the time from the MAC, which is only
555  * 48 bits long and provides meta-information in the top 2 bits.
556  */
557 static ktime_t
efx_ptp_mac_nic_to_ktime_correction(struct efx_nic * efx,struct efx_ptp_data * ptp,u32 nic_major,u32 nic_minor,s32 correction)558 efx_ptp_mac_nic_to_ktime_correction(struct efx_nic *efx,
559 				    struct efx_ptp_data *ptp,
560 				    u32 nic_major, u32 nic_minor,
561 				    s32 correction)
562 {
563 	u32 sync_timestamp;
564 	ktime_t kt = { 0 };
565 	s16 delta;
566 
567 	if (!(nic_major & 0x80000000)) {
568 		WARN_ON_ONCE(nic_major >> 16);
569 
570 		/* Medford provides 48 bits of timestamp, so we must get the top
571 		 * 16 bits from the timesync event state.
572 		 *
573 		 * We only have the lower 16 bits of the time now, but we do
574 		 * have a full resolution timestamp at some point in past. As
575 		 * long as the difference between the (real) now and the sync
576 		 * is less than 2^15, then we can reconstruct the difference
577 		 * between those two numbers using only the lower 16 bits of
578 		 * each.
579 		 *
580 		 * Put another way
581 		 *
582 		 * a - b = ((a mod k) - b) mod k
583 		 *
584 		 * when -k/2 < (a-b) < k/2. In our case k is 2^16. We know
585 		 * (a mod k) and b, so can calculate the delta, a - b.
586 		 *
587 		 */
588 		sync_timestamp = last_sync_timestamp_major(efx);
589 
590 		/* Because delta is s16 this does an implicit mask down to
591 		 * 16 bits which is what we need, assuming
592 		 * MEDFORD_TX_SECS_EVENT_BITS is 16. delta is signed so that
593 		 * we can deal with the (unlikely) case of sync timestamps
594 		 * arriving from the future.
595 		 */
596 		delta = nic_major - sync_timestamp;
597 
598 		/* Recover the fully specified time now, by applying the offset
599 		 * to the (fully specified) sync time.
600 		 */
601 		nic_major = sync_timestamp + delta;
602 
603 		kt = ptp->nic_to_kernel_time(nic_major, nic_minor,
604 					     correction);
605 	}
606 	return kt;
607 }
608 
efx_siena_ptp_nic_to_kernel_time(struct efx_tx_queue * tx_queue)609 ktime_t efx_siena_ptp_nic_to_kernel_time(struct efx_tx_queue *tx_queue)
610 {
611 	struct efx_nic *efx = tx_queue->efx;
612 	struct efx_ptp_data *ptp = efx->ptp_data;
613 	ktime_t kt;
614 
615 	if (efx_siena_ptp_use_mac_tx_timestamps(efx))
616 		kt = efx_ptp_mac_nic_to_ktime_correction(efx, ptp,
617 				tx_queue->completed_timestamp_major,
618 				tx_queue->completed_timestamp_minor,
619 				ptp->ts_corrections.general_tx);
620 	else
621 		kt = ptp->nic_to_kernel_time(
622 				tx_queue->completed_timestamp_major,
623 				tx_queue->completed_timestamp_minor,
624 				ptp->ts_corrections.general_tx);
625 	return kt;
626 }
627 
628 /* Get PTP attributes and set up time conversions */
efx_ptp_get_attributes(struct efx_nic * efx)629 static int efx_ptp_get_attributes(struct efx_nic *efx)
630 {
631 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_GET_ATTRIBUTES_LEN);
632 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_GET_ATTRIBUTES_LEN);
633 	struct efx_ptp_data *ptp = efx->ptp_data;
634 	int rc;
635 	u32 fmt;
636 	size_t out_len;
637 
638 	/* Get the PTP attributes. If the NIC doesn't support the operation we
639 	 * use the default format for compatibility with older NICs i.e.
640 	 * seconds and nanoseconds.
641 	 */
642 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_GET_ATTRIBUTES);
643 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
644 	rc = efx_siena_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
645 				      outbuf, sizeof(outbuf), &out_len);
646 	if (rc == 0) {
647 		fmt = MCDI_DWORD(outbuf, PTP_OUT_GET_ATTRIBUTES_TIME_FORMAT);
648 	} else if (rc == -EINVAL) {
649 		fmt = MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_NANOSECONDS;
650 	} else if (rc == -EPERM) {
651 		pci_info(efx->pci_dev, "no PTP support\n");
652 		return rc;
653 	} else {
654 		efx_siena_mcdi_display_error(efx, MC_CMD_PTP, sizeof(inbuf),
655 					     outbuf, sizeof(outbuf), rc);
656 		return rc;
657 	}
658 
659 	switch (fmt) {
660 	case MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_27FRACTION:
661 		ptp->ns_to_nic_time = efx_ptp_ns_to_s27;
662 		ptp->nic_to_kernel_time = efx_ptp_s27_to_ktime_correction;
663 		ptp->nic_time.minor_max = 1 << 27;
664 		ptp->nic_time.sync_event_minor_shift = 19;
665 		break;
666 	case MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_NANOSECONDS:
667 		ptp->ns_to_nic_time = efx_ptp_ns_to_s_ns;
668 		ptp->nic_to_kernel_time = efx_ptp_s_ns_to_ktime_correction;
669 		ptp->nic_time.minor_max = 1000000000;
670 		ptp->nic_time.sync_event_minor_shift = 22;
671 		break;
672 	case MC_CMD_PTP_OUT_GET_ATTRIBUTES_SECONDS_QTR_NANOSECONDS:
673 		ptp->ns_to_nic_time = efx_ptp_ns_to_s_qns;
674 		ptp->nic_to_kernel_time = efx_ptp_s_qns_to_ktime_correction;
675 		ptp->nic_time.minor_max = 4000000000UL;
676 		ptp->nic_time.sync_event_minor_shift = 24;
677 		break;
678 	default:
679 		return -ERANGE;
680 	}
681 
682 	/* Precalculate acceptable difference between the minor time in the
683 	 * packet prefix and the last MCDI time sync event. We expect the
684 	 * packet prefix timestamp to be after of sync event by up to one
685 	 * sync event interval (0.25s) but we allow it to exceed this by a
686 	 * fuzz factor of (0.1s)
687 	 */
688 	ptp->nic_time.sync_event_diff_min = ptp->nic_time.minor_max
689 		- (ptp->nic_time.minor_max / 10);
690 	ptp->nic_time.sync_event_diff_max = (ptp->nic_time.minor_max / 4)
691 		+ (ptp->nic_time.minor_max / 10);
692 
693 	/* MC_CMD_PTP_OP_GET_ATTRIBUTES has been extended twice from an older
694 	 * operation MC_CMD_PTP_OP_GET_TIME_FORMAT. The function now may return
695 	 * a value to use for the minimum acceptable corrected synchronization
696 	 * window and may return further capabilities.
697 	 * If we have the extra information store it. For older firmware that
698 	 * does not implement the extended command use the default value.
699 	 */
700 	if (rc == 0 &&
701 	    out_len >= MC_CMD_PTP_OUT_GET_ATTRIBUTES_CAPABILITIES_OFST)
702 		ptp->min_synchronisation_ns =
703 			MCDI_DWORD(outbuf,
704 				   PTP_OUT_GET_ATTRIBUTES_SYNC_WINDOW_MIN);
705 	else
706 		ptp->min_synchronisation_ns = DEFAULT_MIN_SYNCHRONISATION_NS;
707 
708 	if (rc == 0 &&
709 	    out_len >= MC_CMD_PTP_OUT_GET_ATTRIBUTES_LEN)
710 		ptp->capabilities = MCDI_DWORD(outbuf,
711 					PTP_OUT_GET_ATTRIBUTES_CAPABILITIES);
712 	else
713 		ptp->capabilities = 0;
714 
715 	/* Set up the shift for conversion between frequency
716 	 * adjustments in parts-per-billion and the fixed-point
717 	 * fractional ns format that the adapter uses.
718 	 */
719 	if (ptp->capabilities & (1 << MC_CMD_PTP_OUT_GET_ATTRIBUTES_FP44_FREQ_ADJ_LBN))
720 		ptp->adjfreq_ppb_shift = PPB_SHIFT_FP44;
721 	else
722 		ptp->adjfreq_ppb_shift = PPB_SHIFT_FP40;
723 
724 	return 0;
725 }
726 
727 /* Get PTP timestamp corrections */
efx_ptp_get_timestamp_corrections(struct efx_nic * efx)728 static int efx_ptp_get_timestamp_corrections(struct efx_nic *efx)
729 {
730 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_GET_TIMESTAMP_CORRECTIONS_LEN);
731 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_LEN);
732 	int rc;
733 	size_t out_len;
734 
735 	/* Get the timestamp corrections from the NIC. If this operation is
736 	 * not supported (older NICs) then no correction is required.
737 	 */
738 	MCDI_SET_DWORD(inbuf, PTP_IN_OP,
739 		       MC_CMD_PTP_OP_GET_TIMESTAMP_CORRECTIONS);
740 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
741 
742 	rc = efx_siena_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
743 				      outbuf, sizeof(outbuf), &out_len);
744 	if (rc == 0) {
745 		efx->ptp_data->ts_corrections.ptp_tx = MCDI_DWORD(outbuf,
746 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_TRANSMIT);
747 		efx->ptp_data->ts_corrections.ptp_rx = MCDI_DWORD(outbuf,
748 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_RECEIVE);
749 		efx->ptp_data->ts_corrections.pps_out = MCDI_DWORD(outbuf,
750 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_PPS_OUT);
751 		efx->ptp_data->ts_corrections.pps_in = MCDI_DWORD(outbuf,
752 			PTP_OUT_GET_TIMESTAMP_CORRECTIONS_PPS_IN);
753 
754 		if (out_len >= MC_CMD_PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_LEN) {
755 			efx->ptp_data->ts_corrections.general_tx = MCDI_DWORD(
756 				outbuf,
757 				PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_GENERAL_TX);
758 			efx->ptp_data->ts_corrections.general_rx = MCDI_DWORD(
759 				outbuf,
760 				PTP_OUT_GET_TIMESTAMP_CORRECTIONS_V2_GENERAL_RX);
761 		} else {
762 			efx->ptp_data->ts_corrections.general_tx =
763 				efx->ptp_data->ts_corrections.ptp_tx;
764 			efx->ptp_data->ts_corrections.general_rx =
765 				efx->ptp_data->ts_corrections.ptp_rx;
766 		}
767 	} else if (rc == -EINVAL) {
768 		efx->ptp_data->ts_corrections.ptp_tx = 0;
769 		efx->ptp_data->ts_corrections.ptp_rx = 0;
770 		efx->ptp_data->ts_corrections.pps_out = 0;
771 		efx->ptp_data->ts_corrections.pps_in = 0;
772 		efx->ptp_data->ts_corrections.general_tx = 0;
773 		efx->ptp_data->ts_corrections.general_rx = 0;
774 	} else {
775 		efx_siena_mcdi_display_error(efx, MC_CMD_PTP, sizeof(inbuf),
776 					     outbuf, sizeof(outbuf), rc);
777 		return rc;
778 	}
779 
780 	return 0;
781 }
782 
783 /* Enable MCDI PTP support. */
efx_ptp_enable(struct efx_nic * efx)784 static int efx_ptp_enable(struct efx_nic *efx)
785 {
786 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_ENABLE_LEN);
787 	MCDI_DECLARE_BUF_ERR(outbuf);
788 	int rc;
789 
790 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_ENABLE);
791 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
792 	MCDI_SET_DWORD(inbuf, PTP_IN_ENABLE_QUEUE,
793 		       efx->ptp_data->channel ?
794 		       efx->ptp_data->channel->channel : 0);
795 	MCDI_SET_DWORD(inbuf, PTP_IN_ENABLE_MODE, efx->ptp_data->mode);
796 
797 	rc = efx_siena_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
798 				      outbuf, sizeof(outbuf), NULL);
799 	rc = (rc == -EALREADY) ? 0 : rc;
800 	if (rc)
801 		efx_siena_mcdi_display_error(efx, MC_CMD_PTP,
802 					     MC_CMD_PTP_IN_ENABLE_LEN,
803 					     outbuf, sizeof(outbuf), rc);
804 	return rc;
805 }
806 
807 /* Disable MCDI PTP support.
808  *
809  * Note that this function should never rely on the presence of ptp_data -
810  * may be called before that exists.
811  */
efx_ptp_disable(struct efx_nic * efx)812 static int efx_ptp_disable(struct efx_nic *efx)
813 {
814 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_DISABLE_LEN);
815 	MCDI_DECLARE_BUF_ERR(outbuf);
816 	int rc;
817 
818 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_DISABLE);
819 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
820 	rc = efx_siena_mcdi_rpc_quiet(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
821 				      outbuf, sizeof(outbuf), NULL);
822 	rc = (rc == -EALREADY) ? 0 : rc;
823 	/* If we get ENOSYS, the NIC doesn't support PTP, and thus this function
824 	 * should only have been called during probe.
825 	 */
826 	if (rc == -ENOSYS || rc == -EPERM)
827 		pci_info(efx->pci_dev, "no PTP support\n");
828 	else if (rc)
829 		efx_siena_mcdi_display_error(efx, MC_CMD_PTP,
830 					     MC_CMD_PTP_IN_DISABLE_LEN,
831 					     outbuf, sizeof(outbuf), rc);
832 	return rc;
833 }
834 
efx_ptp_deliver_rx_queue(struct sk_buff_head * q)835 static void efx_ptp_deliver_rx_queue(struct sk_buff_head *q)
836 {
837 	struct sk_buff *skb;
838 
839 	while ((skb = skb_dequeue(q))) {
840 		local_bh_disable();
841 		netif_receive_skb(skb);
842 		local_bh_enable();
843 	}
844 }
845 
efx_ptp_handle_no_channel(struct efx_nic * efx)846 static void efx_ptp_handle_no_channel(struct efx_nic *efx)
847 {
848 	netif_err(efx, drv, efx->net_dev,
849 		  "ERROR: PTP requires MSI-X and 1 additional interrupt"
850 		  "vector. PTP disabled\n");
851 }
852 
853 /* Repeatedly send the host time to the MC which will capture the hardware
854  * time.
855  */
efx_ptp_send_times(struct efx_nic * efx,struct pps_event_time * last_time)856 static void efx_ptp_send_times(struct efx_nic *efx,
857 			       struct pps_event_time *last_time)
858 {
859 	struct pps_event_time now;
860 	struct timespec64 limit;
861 	struct efx_ptp_data *ptp = efx->ptp_data;
862 	int *mc_running = ptp->start.addr;
863 
864 	pps_get_ts(&now);
865 	limit = now.ts_real;
866 	timespec64_add_ns(&limit, SYNCHRONISE_PERIOD_NS);
867 
868 	/* Write host time for specified period or until MC is done */
869 	while ((timespec64_compare(&now.ts_real, &limit) < 0) &&
870 	       READ_ONCE(*mc_running)) {
871 		struct timespec64 update_time;
872 		unsigned int host_time;
873 
874 		/* Don't update continuously to avoid saturating the PCIe bus */
875 		update_time = now.ts_real;
876 		timespec64_add_ns(&update_time, SYNCHRONISATION_GRANULARITY_NS);
877 		do {
878 			pps_get_ts(&now);
879 		} while ((timespec64_compare(&now.ts_real, &update_time) < 0) &&
880 			 READ_ONCE(*mc_running));
881 
882 		/* Synchronise NIC with single word of time only */
883 		host_time = (now.ts_real.tv_sec << MC_NANOSECOND_BITS |
884 			     now.ts_real.tv_nsec);
885 		/* Update host time in NIC memory */
886 		efx->type->ptp_write_host_time(efx, host_time);
887 	}
888 	*last_time = now;
889 }
890 
891 /* 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)892 static void efx_ptp_read_timeset(MCDI_DECLARE_STRUCT_PTR(data),
893 				 struct efx_ptp_timeset *timeset)
894 {
895 	unsigned start_ns, end_ns;
896 
897 	timeset->host_start = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTSTART);
898 	timeset->major = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_MAJOR);
899 	timeset->minor = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_MINOR);
900 	timeset->host_end = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_HOSTEND);
901 	timeset->wait = MCDI_DWORD(data, PTP_OUT_SYNCHRONIZE_WAITNS);
902 
903 	/* Ignore seconds */
904 	start_ns = timeset->host_start & MC_NANOSECOND_MASK;
905 	end_ns = timeset->host_end & MC_NANOSECOND_MASK;
906 	/* Allow for rollover */
907 	if (end_ns < start_ns)
908 		end_ns += NSEC_PER_SEC;
909 	/* Determine duration of operation */
910 	timeset->window = end_ns - start_ns;
911 }
912 
913 /* Process times received from MC.
914  *
915  * Extract times from returned results, and establish the minimum value
916  * seen.  The minimum value represents the "best" possible time and events
917  * too much greater than this are rejected - the machine is, perhaps, too
918  * busy. A number of readings are taken so that, hopefully, at least one good
919  * synchronisation will be seen in the results.
920  */
921 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)922 efx_ptp_process_times(struct efx_nic *efx, MCDI_DECLARE_STRUCT_PTR(synch_buf),
923 		      size_t response_length,
924 		      const struct pps_event_time *last_time)
925 {
926 	unsigned number_readings =
927 		MCDI_VAR_ARRAY_LEN(response_length,
928 				   PTP_OUT_SYNCHRONIZE_TIMESET);
929 	unsigned i;
930 	unsigned ngood = 0;
931 	unsigned last_good = 0;
932 	struct efx_ptp_data *ptp = efx->ptp_data;
933 	u32 last_sec;
934 	u32 start_sec;
935 	struct timespec64 delta;
936 	ktime_t mc_time;
937 
938 	if (number_readings == 0)
939 		return -EAGAIN;
940 
941 	/* Read the set of results and find the last good host-MC
942 	 * synchronization result. The MC times when it finishes reading the
943 	 * host time so the corrected window time should be fairly constant
944 	 * for a given platform. Increment stats for any results that appear
945 	 * to be erroneous.
946 	 */
947 	for (i = 0; i < number_readings; i++) {
948 		s32 window, corrected;
949 		struct timespec64 wait;
950 
951 		efx_ptp_read_timeset(
952 			MCDI_ARRAY_STRUCT_PTR(synch_buf,
953 					      PTP_OUT_SYNCHRONIZE_TIMESET, i),
954 			&ptp->timeset[i]);
955 
956 		wait = ktime_to_timespec64(
957 			ptp->nic_to_kernel_time(0, ptp->timeset[i].wait, 0));
958 		window = ptp->timeset[i].window;
959 		corrected = window - wait.tv_nsec;
960 
961 		/* We expect the uncorrected synchronization window to be at
962 		 * least as large as the interval between host start and end
963 		 * times. If it is smaller than this then this is mostly likely
964 		 * to be a consequence of the host's time being adjusted.
965 		 * Check that the corrected sync window is in a reasonable
966 		 * range. If it is out of range it is likely to be because an
967 		 * interrupt or other delay occurred between reading the system
968 		 * time and writing it to MC memory.
969 		 */
970 		if (window < SYNCHRONISATION_GRANULARITY_NS) {
971 			++ptp->invalid_sync_windows;
972 		} else if (corrected >= MAX_SYNCHRONISATION_NS) {
973 			++ptp->oversize_sync_windows;
974 		} else if (corrected < ptp->min_synchronisation_ns) {
975 			++ptp->undersize_sync_windows;
976 		} else {
977 			ngood++;
978 			last_good = i;
979 		}
980 	}
981 
982 	if (ngood == 0) {
983 		netif_warn(efx, drv, efx->net_dev,
984 			   "PTP no suitable synchronisations\n");
985 		return -EAGAIN;
986 	}
987 
988 	/* Calculate delay from last good sync (host time) to last_time.
989 	 * It is possible that the seconds rolled over between taking
990 	 * the start reading and the last value written by the host.  The
991 	 * timescales are such that a gap of more than one second is never
992 	 * expected.  delta is *not* normalised.
993 	 */
994 	start_sec = ptp->timeset[last_good].host_start >> MC_NANOSECOND_BITS;
995 	last_sec = last_time->ts_real.tv_sec & MC_SECOND_MASK;
996 	if (start_sec != last_sec &&
997 	    ((start_sec + 1) & MC_SECOND_MASK) != last_sec) {
998 		netif_warn(efx, hw, efx->net_dev,
999 			   "PTP bad synchronisation seconds\n");
1000 		return -EAGAIN;
1001 	}
1002 	delta.tv_sec = (last_sec - start_sec) & 1;
1003 	delta.tv_nsec =
1004 		last_time->ts_real.tv_nsec -
1005 		(ptp->timeset[last_good].host_start & MC_NANOSECOND_MASK);
1006 
1007 	/* Convert the NIC time at last good sync into kernel time.
1008 	 * No correction is required - this time is the output of a
1009 	 * firmware process.
1010 	 */
1011 	mc_time = ptp->nic_to_kernel_time(ptp->timeset[last_good].major,
1012 					  ptp->timeset[last_good].minor, 0);
1013 
1014 	/* Calculate delay from NIC top of second to last_time */
1015 	delta.tv_nsec += ktime_to_timespec64(mc_time).tv_nsec;
1016 
1017 	/* Set PPS timestamp to match NIC top of second */
1018 	ptp->host_time_pps = *last_time;
1019 	pps_sub_ts(&ptp->host_time_pps, delta);
1020 
1021 	return 0;
1022 }
1023 
1024 /* Synchronize times between the host and the MC */
efx_ptp_synchronize(struct efx_nic * efx,unsigned int num_readings)1025 static int efx_ptp_synchronize(struct efx_nic *efx, unsigned int num_readings)
1026 {
1027 	struct efx_ptp_data *ptp = efx->ptp_data;
1028 	MCDI_DECLARE_BUF(synch_buf, MC_CMD_PTP_OUT_SYNCHRONIZE_LENMAX);
1029 	size_t response_length;
1030 	int rc;
1031 	unsigned long timeout;
1032 	struct pps_event_time last_time = {};
1033 	unsigned int loops = 0;
1034 	int *start = ptp->start.addr;
1035 
1036 	MCDI_SET_DWORD(synch_buf, PTP_IN_OP, MC_CMD_PTP_OP_SYNCHRONIZE);
1037 	MCDI_SET_DWORD(synch_buf, PTP_IN_PERIPH_ID, 0);
1038 	MCDI_SET_DWORD(synch_buf, PTP_IN_SYNCHRONIZE_NUMTIMESETS,
1039 		       num_readings);
1040 	MCDI_SET_QWORD(synch_buf, PTP_IN_SYNCHRONIZE_START_ADDR,
1041 		       ptp->start.dma_addr);
1042 
1043 	/* Clear flag that signals MC ready */
1044 	WRITE_ONCE(*start, 0);
1045 	rc = efx_siena_mcdi_rpc_start(efx, MC_CMD_PTP, synch_buf,
1046 				      MC_CMD_PTP_IN_SYNCHRONIZE_LEN);
1047 	EFX_WARN_ON_ONCE_PARANOID(rc);
1048 
1049 	/* Wait for start from MCDI (or timeout) */
1050 	timeout = jiffies + msecs_to_jiffies(MAX_SYNCHRONISE_WAIT_MS);
1051 	while (!READ_ONCE(*start) && (time_before(jiffies, timeout))) {
1052 		udelay(20);	/* Usually start MCDI execution quickly */
1053 		loops++;
1054 	}
1055 
1056 	if (loops <= 1)
1057 		++ptp->fast_syncs;
1058 	if (!time_before(jiffies, timeout))
1059 		++ptp->sync_timeouts;
1060 
1061 	if (READ_ONCE(*start))
1062 		efx_ptp_send_times(efx, &last_time);
1063 
1064 	/* Collect results */
1065 	rc = efx_siena_mcdi_rpc_finish(efx, MC_CMD_PTP,
1066 				       MC_CMD_PTP_IN_SYNCHRONIZE_LEN,
1067 				       synch_buf, sizeof(synch_buf),
1068 				       &response_length);
1069 	if (rc == 0) {
1070 		rc = efx_ptp_process_times(efx, synch_buf, response_length,
1071 					   &last_time);
1072 		if (rc == 0)
1073 			++ptp->good_syncs;
1074 		else
1075 			++ptp->no_time_syncs;
1076 	}
1077 
1078 	/* Increment the bad syncs counter if the synchronize fails, whatever
1079 	 * the reason.
1080 	 */
1081 	if (rc != 0)
1082 		++ptp->bad_syncs;
1083 
1084 	return rc;
1085 }
1086 
1087 /* Transmit a PTP packet via the dedicated hardware timestamped queue. */
efx_ptp_xmit_skb_queue(struct efx_nic * efx,struct sk_buff * skb)1088 static void efx_ptp_xmit_skb_queue(struct efx_nic *efx, struct sk_buff *skb)
1089 {
1090 	struct efx_ptp_data *ptp_data = efx->ptp_data;
1091 	u8 type = efx_tx_csum_type_skb(skb);
1092 	struct efx_tx_queue *tx_queue;
1093 
1094 	tx_queue = efx_channel_get_tx_queue(ptp_data->channel, type);
1095 	if (tx_queue && tx_queue->timestamping) {
1096 		efx_enqueue_skb(tx_queue, skb);
1097 	} else {
1098 		WARN_ONCE(1, "PTP channel has no timestamped tx queue\n");
1099 		dev_kfree_skb_any(skb);
1100 	}
1101 }
1102 
1103 /* Transmit a PTP packet, via the MCDI interface, to the wire. */
efx_ptp_xmit_skb_mc(struct efx_nic * efx,struct sk_buff * skb)1104 static void efx_ptp_xmit_skb_mc(struct efx_nic *efx, struct sk_buff *skb)
1105 {
1106 	struct efx_ptp_data *ptp_data = efx->ptp_data;
1107 	struct skb_shared_hwtstamps timestamps;
1108 	int rc = -EIO;
1109 	MCDI_DECLARE_BUF(txtime, MC_CMD_PTP_OUT_TRANSMIT_LEN);
1110 	size_t len;
1111 
1112 	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_OP, MC_CMD_PTP_OP_TRANSMIT);
1113 	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_PERIPH_ID, 0);
1114 	MCDI_SET_DWORD(ptp_data->txbuf, PTP_IN_TRANSMIT_LENGTH, skb->len);
1115 	if (skb_shinfo(skb)->nr_frags != 0) {
1116 		rc = skb_linearize(skb);
1117 		if (rc != 0)
1118 			goto fail;
1119 	}
1120 
1121 	if (skb->ip_summed == CHECKSUM_PARTIAL) {
1122 		rc = skb_checksum_help(skb);
1123 		if (rc != 0)
1124 			goto fail;
1125 	}
1126 	skb_copy_from_linear_data(skb,
1127 				  MCDI_PTR(ptp_data->txbuf,
1128 					   PTP_IN_TRANSMIT_PACKET),
1129 				  skb->len);
1130 	rc = efx_siena_mcdi_rpc(efx, MC_CMD_PTP, ptp_data->txbuf,
1131 				MC_CMD_PTP_IN_TRANSMIT_LEN(skb->len), txtime,
1132 				sizeof(txtime), &len);
1133 	if (rc != 0)
1134 		goto fail;
1135 
1136 	memset(&timestamps, 0, sizeof(timestamps));
1137 	timestamps.hwtstamp = ptp_data->nic_to_kernel_time(
1138 		MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_MAJOR),
1139 		MCDI_DWORD(txtime, PTP_OUT_TRANSMIT_MINOR),
1140 		ptp_data->ts_corrections.ptp_tx);
1141 
1142 	skb_tstamp_tx(skb, &timestamps);
1143 
1144 	rc = 0;
1145 
1146 fail:
1147 	dev_kfree_skb_any(skb);
1148 
1149 	return;
1150 }
1151 
efx_ptp_drop_time_expired_events(struct efx_nic * efx)1152 static void efx_ptp_drop_time_expired_events(struct efx_nic *efx)
1153 {
1154 	struct efx_ptp_data *ptp = efx->ptp_data;
1155 	struct list_head *cursor;
1156 	struct list_head *next;
1157 
1158 	if (ptp->rx_ts_inline)
1159 		return;
1160 
1161 	/* Drop time-expired events */
1162 	spin_lock_bh(&ptp->evt_lock);
1163 	list_for_each_safe(cursor, next, &ptp->evt_list) {
1164 		struct efx_ptp_event_rx *evt;
1165 
1166 		evt = list_entry(cursor, struct efx_ptp_event_rx,
1167 				 link);
1168 		if (time_after(jiffies, evt->expiry)) {
1169 			list_move(&evt->link, &ptp->evt_free_list);
1170 			netif_warn(efx, hw, efx->net_dev,
1171 				   "PTP rx event dropped\n");
1172 		}
1173 	}
1174 	spin_unlock_bh(&ptp->evt_lock);
1175 }
1176 
efx_ptp_match_rx(struct efx_nic * efx,struct sk_buff * skb)1177 static enum ptp_packet_state efx_ptp_match_rx(struct efx_nic *efx,
1178 					      struct sk_buff *skb)
1179 {
1180 	struct efx_ptp_data *ptp = efx->ptp_data;
1181 	bool evts_waiting;
1182 	struct list_head *cursor;
1183 	struct list_head *next;
1184 	struct efx_ptp_match *match;
1185 	enum ptp_packet_state rc = PTP_PACKET_STATE_UNMATCHED;
1186 
1187 	WARN_ON_ONCE(ptp->rx_ts_inline);
1188 
1189 	spin_lock_bh(&ptp->evt_lock);
1190 	evts_waiting = !list_empty(&ptp->evt_list);
1191 	spin_unlock_bh(&ptp->evt_lock);
1192 
1193 	if (!evts_waiting)
1194 		return PTP_PACKET_STATE_UNMATCHED;
1195 
1196 	match = (struct efx_ptp_match *)skb->cb;
1197 	/* Look for a matching timestamp in the event queue */
1198 	spin_lock_bh(&ptp->evt_lock);
1199 	list_for_each_safe(cursor, next, &ptp->evt_list) {
1200 		struct efx_ptp_event_rx *evt;
1201 
1202 		evt = list_entry(cursor, struct efx_ptp_event_rx, link);
1203 		if ((evt->seq0 == match->words[0]) &&
1204 		    (evt->seq1 == match->words[1])) {
1205 			struct skb_shared_hwtstamps *timestamps;
1206 
1207 			/* Match - add in hardware timestamp */
1208 			timestamps = skb_hwtstamps(skb);
1209 			timestamps->hwtstamp = evt->hwtimestamp;
1210 
1211 			match->state = PTP_PACKET_STATE_MATCHED;
1212 			rc = PTP_PACKET_STATE_MATCHED;
1213 			list_move(&evt->link, &ptp->evt_free_list);
1214 			break;
1215 		}
1216 	}
1217 	spin_unlock_bh(&ptp->evt_lock);
1218 
1219 	return rc;
1220 }
1221 
1222 /* Process any queued receive events and corresponding packets
1223  *
1224  * q is returned with all the packets that are ready for delivery.
1225  */
efx_ptp_process_events(struct efx_nic * efx,struct sk_buff_head * q)1226 static void efx_ptp_process_events(struct efx_nic *efx, struct sk_buff_head *q)
1227 {
1228 	struct efx_ptp_data *ptp = efx->ptp_data;
1229 	struct sk_buff *skb;
1230 
1231 	while ((skb = skb_dequeue(&ptp->rxq))) {
1232 		struct efx_ptp_match *match;
1233 
1234 		match = (struct efx_ptp_match *)skb->cb;
1235 		if (match->state == PTP_PACKET_STATE_MATCH_UNWANTED) {
1236 			__skb_queue_tail(q, skb);
1237 		} else if (efx_ptp_match_rx(efx, skb) ==
1238 			   PTP_PACKET_STATE_MATCHED) {
1239 			__skb_queue_tail(q, skb);
1240 		} else if (time_after(jiffies, match->expiry)) {
1241 			match->state = PTP_PACKET_STATE_TIMED_OUT;
1242 			++ptp->rx_no_timestamp;
1243 			__skb_queue_tail(q, skb);
1244 		} else {
1245 			/* Replace unprocessed entry and stop */
1246 			skb_queue_head(&ptp->rxq, skb);
1247 			break;
1248 		}
1249 	}
1250 }
1251 
1252 /* Complete processing of a received packet */
efx_ptp_process_rx(struct efx_nic * efx,struct sk_buff * skb)1253 static inline void efx_ptp_process_rx(struct efx_nic *efx, struct sk_buff *skb)
1254 {
1255 	local_bh_disable();
1256 	netif_receive_skb(skb);
1257 	local_bh_enable();
1258 }
1259 
efx_ptp_remove_multicast_filters(struct efx_nic * efx)1260 static void efx_ptp_remove_multicast_filters(struct efx_nic *efx)
1261 {
1262 	struct efx_ptp_data *ptp = efx->ptp_data;
1263 
1264 	if (ptp->rxfilter_installed) {
1265 		efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED,
1266 					  ptp->rxfilter_general);
1267 		efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED,
1268 					  ptp->rxfilter_event);
1269 		ptp->rxfilter_installed = false;
1270 	}
1271 }
1272 
efx_ptp_insert_multicast_filters(struct efx_nic * efx)1273 static int efx_ptp_insert_multicast_filters(struct efx_nic *efx)
1274 {
1275 	struct efx_ptp_data *ptp = efx->ptp_data;
1276 	struct efx_filter_spec rxfilter;
1277 	int rc;
1278 
1279 	if (!ptp->channel || ptp->rxfilter_installed)
1280 		return 0;
1281 
1282 	/* Must filter on both event and general ports to ensure
1283 	 * that there is no packet re-ordering.
1284 	 */
1285 	efx_filter_init_rx(&rxfilter, EFX_FILTER_PRI_REQUIRED, 0,
1286 			   efx_rx_queue_index(
1287 				   efx_channel_get_rx_queue(ptp->channel)));
1288 	rc = efx_filter_set_ipv4_local(&rxfilter, IPPROTO_UDP,
1289 				       htonl(PTP_ADDRESS),
1290 				       htons(PTP_EVENT_PORT));
1291 	if (rc != 0)
1292 		return rc;
1293 
1294 	rc = efx_filter_insert_filter(efx, &rxfilter, true);
1295 	if (rc < 0)
1296 		return rc;
1297 	ptp->rxfilter_event = rc;
1298 
1299 	efx_filter_init_rx(&rxfilter, EFX_FILTER_PRI_REQUIRED, 0,
1300 			   efx_rx_queue_index(
1301 				   efx_channel_get_rx_queue(ptp->channel)));
1302 	rc = efx_filter_set_ipv4_local(&rxfilter, IPPROTO_UDP,
1303 				       htonl(PTP_ADDRESS),
1304 				       htons(PTP_GENERAL_PORT));
1305 	if (rc != 0)
1306 		goto fail;
1307 
1308 	rc = efx_filter_insert_filter(efx, &rxfilter, true);
1309 	if (rc < 0)
1310 		goto fail;
1311 	ptp->rxfilter_general = rc;
1312 
1313 	ptp->rxfilter_installed = true;
1314 	return 0;
1315 
1316 fail:
1317 	efx_filter_remove_id_safe(efx, EFX_FILTER_PRI_REQUIRED,
1318 				  ptp->rxfilter_event);
1319 	return rc;
1320 }
1321 
efx_ptp_start(struct efx_nic * efx)1322 static int efx_ptp_start(struct efx_nic *efx)
1323 {
1324 	struct efx_ptp_data *ptp = efx->ptp_data;
1325 	int rc;
1326 
1327 	ptp->reset_required = false;
1328 
1329 	rc = efx_ptp_insert_multicast_filters(efx);
1330 	if (rc)
1331 		return rc;
1332 
1333 	rc = efx_ptp_enable(efx);
1334 	if (rc != 0)
1335 		goto fail;
1336 
1337 	ptp->evt_frag_idx = 0;
1338 	ptp->current_adjfreq = 0;
1339 
1340 	return 0;
1341 
1342 fail:
1343 	efx_ptp_remove_multicast_filters(efx);
1344 	return rc;
1345 }
1346 
efx_ptp_stop(struct efx_nic * efx)1347 static int efx_ptp_stop(struct efx_nic *efx)
1348 {
1349 	struct efx_ptp_data *ptp = efx->ptp_data;
1350 	struct list_head *cursor;
1351 	struct list_head *next;
1352 	int rc;
1353 
1354 	if (ptp == NULL)
1355 		return 0;
1356 
1357 	rc = efx_ptp_disable(efx);
1358 
1359 	efx_ptp_remove_multicast_filters(efx);
1360 
1361 	/* Make sure RX packets are really delivered */
1362 	efx_ptp_deliver_rx_queue(&efx->ptp_data->rxq);
1363 	skb_queue_purge(&efx->ptp_data->txq);
1364 
1365 	/* Drop any pending receive events */
1366 	spin_lock_bh(&efx->ptp_data->evt_lock);
1367 	list_for_each_safe(cursor, next, &efx->ptp_data->evt_list) {
1368 		list_move(cursor, &efx->ptp_data->evt_free_list);
1369 	}
1370 	spin_unlock_bh(&efx->ptp_data->evt_lock);
1371 
1372 	return rc;
1373 }
1374 
efx_ptp_restart(struct efx_nic * efx)1375 static int efx_ptp_restart(struct efx_nic *efx)
1376 {
1377 	if (efx->ptp_data && efx->ptp_data->enabled)
1378 		return efx_ptp_start(efx);
1379 	return 0;
1380 }
1381 
efx_ptp_pps_worker(struct work_struct * work)1382 static void efx_ptp_pps_worker(struct work_struct *work)
1383 {
1384 	struct efx_ptp_data *ptp =
1385 		container_of(work, struct efx_ptp_data, pps_work);
1386 	struct efx_nic *efx = ptp->efx;
1387 	struct ptp_clock_event ptp_evt;
1388 
1389 	if (efx_ptp_synchronize(efx, PTP_SYNC_ATTEMPTS))
1390 		return;
1391 
1392 	ptp_evt.type = PTP_CLOCK_PPSUSR;
1393 	ptp_evt.pps_times = ptp->host_time_pps;
1394 	ptp_clock_event(ptp->phc_clock, &ptp_evt);
1395 }
1396 
efx_ptp_worker(struct work_struct * work)1397 static void efx_ptp_worker(struct work_struct *work)
1398 {
1399 	struct efx_ptp_data *ptp_data =
1400 		container_of(work, struct efx_ptp_data, work);
1401 	struct efx_nic *efx = ptp_data->efx;
1402 	struct sk_buff *skb;
1403 	struct sk_buff_head tempq;
1404 
1405 	if (ptp_data->reset_required) {
1406 		efx_ptp_stop(efx);
1407 		efx_ptp_start(efx);
1408 		return;
1409 	}
1410 
1411 	efx_ptp_drop_time_expired_events(efx);
1412 
1413 	__skb_queue_head_init(&tempq);
1414 	efx_ptp_process_events(efx, &tempq);
1415 
1416 	while ((skb = skb_dequeue(&ptp_data->txq)))
1417 		ptp_data->xmit_skb(efx, skb);
1418 
1419 	while ((skb = __skb_dequeue(&tempq)))
1420 		efx_ptp_process_rx(efx, skb);
1421 }
1422 
1423 static const struct ptp_clock_info efx_phc_clock_info = {
1424 	.owner		= THIS_MODULE,
1425 	.name		= "sfc_siena",
1426 	.max_adj	= MAX_PPB,
1427 	.n_alarm	= 0,
1428 	.n_ext_ts	= 0,
1429 	.n_per_out	= 0,
1430 	.n_pins		= 0,
1431 	.pps		= 1,
1432 	.adjfine	= efx_phc_adjfine,
1433 	.adjtime	= efx_phc_adjtime,
1434 	.gettime64	= efx_phc_gettime,
1435 	.settime64	= efx_phc_settime,
1436 	.enable		= efx_phc_enable,
1437 };
1438 
1439 /* Initialise PTP state. */
efx_ptp_probe(struct efx_nic * efx,struct efx_channel * channel)1440 static int efx_ptp_probe(struct efx_nic *efx, struct efx_channel *channel)
1441 {
1442 	struct efx_ptp_data *ptp;
1443 	int rc = 0;
1444 	unsigned int pos;
1445 
1446 	ptp = kzalloc(sizeof(struct efx_ptp_data), GFP_KERNEL);
1447 	efx->ptp_data = ptp;
1448 	if (!efx->ptp_data)
1449 		return -ENOMEM;
1450 
1451 	ptp->efx = efx;
1452 	ptp->channel = channel;
1453 	ptp->rx_ts_inline = efx_nic_rev(efx) >= EFX_REV_HUNT_A0;
1454 
1455 	rc = efx_siena_alloc_buffer(efx, &ptp->start, sizeof(int), GFP_KERNEL);
1456 	if (rc != 0)
1457 		goto fail1;
1458 
1459 	skb_queue_head_init(&ptp->rxq);
1460 	skb_queue_head_init(&ptp->txq);
1461 	ptp->workwq = create_singlethread_workqueue("sfc_siena_ptp");
1462 	if (!ptp->workwq) {
1463 		rc = -ENOMEM;
1464 		goto fail2;
1465 	}
1466 
1467 	if (efx_siena_ptp_use_mac_tx_timestamps(efx)) {
1468 		ptp->xmit_skb = efx_ptp_xmit_skb_queue;
1469 		/* Request sync events on this channel. */
1470 		channel->sync_events_state = SYNC_EVENTS_QUIESCENT;
1471 	} else {
1472 		ptp->xmit_skb = efx_ptp_xmit_skb_mc;
1473 	}
1474 
1475 	INIT_WORK(&ptp->work, efx_ptp_worker);
1476 	ptp->config.flags = 0;
1477 	ptp->config.tx_type = HWTSTAMP_TX_OFF;
1478 	ptp->config.rx_filter = HWTSTAMP_FILTER_NONE;
1479 	INIT_LIST_HEAD(&ptp->evt_list);
1480 	INIT_LIST_HEAD(&ptp->evt_free_list);
1481 	spin_lock_init(&ptp->evt_lock);
1482 	for (pos = 0; pos < MAX_RECEIVE_EVENTS; pos++)
1483 		list_add(&ptp->rx_evts[pos].link, &ptp->evt_free_list);
1484 
1485 	/* Get the NIC PTP attributes and set up time conversions */
1486 	rc = efx_ptp_get_attributes(efx);
1487 	if (rc < 0)
1488 		goto fail3;
1489 
1490 	/* Get the timestamp corrections */
1491 	rc = efx_ptp_get_timestamp_corrections(efx);
1492 	if (rc < 0)
1493 		goto fail3;
1494 
1495 	if (efx->mcdi->fn_flags &
1496 	    (1 << MC_CMD_DRV_ATTACH_EXT_OUT_FLAG_PRIMARY)) {
1497 		ptp->phc_clock_info = efx_phc_clock_info;
1498 		ptp->phc_clock = ptp_clock_register(&ptp->phc_clock_info,
1499 						    &efx->pci_dev->dev);
1500 		if (IS_ERR(ptp->phc_clock)) {
1501 			rc = PTR_ERR(ptp->phc_clock);
1502 			goto fail3;
1503 		} else if (ptp->phc_clock) {
1504 			INIT_WORK(&ptp->pps_work, efx_ptp_pps_worker);
1505 			ptp->pps_workwq =
1506 				create_singlethread_workqueue("sfc_siena_pps");
1507 			if (!ptp->pps_workwq) {
1508 				rc = -ENOMEM;
1509 				goto fail4;
1510 			}
1511 		}
1512 	}
1513 	ptp->nic_ts_enabled = false;
1514 
1515 	return 0;
1516 fail4:
1517 	ptp_clock_unregister(efx->ptp_data->phc_clock);
1518 
1519 fail3:
1520 	destroy_workqueue(efx->ptp_data->workwq);
1521 
1522 fail2:
1523 	efx_siena_free_buffer(efx, &ptp->start);
1524 
1525 fail1:
1526 	kfree(efx->ptp_data);
1527 	efx->ptp_data = NULL;
1528 
1529 	return rc;
1530 }
1531 
1532 /* Initialise PTP channel.
1533  *
1534  * Setting core_index to zero causes the queue to be initialised and doesn't
1535  * overlap with 'rxq0' because ptp.c doesn't use skb_record_rx_queue.
1536  */
efx_ptp_probe_channel(struct efx_channel * channel)1537 static int efx_ptp_probe_channel(struct efx_channel *channel)
1538 {
1539 	struct efx_nic *efx = channel->efx;
1540 	int rc;
1541 
1542 	channel->irq_moderation_us = 0;
1543 	channel->rx_queue.core_index = 0;
1544 
1545 	rc = efx_ptp_probe(efx, channel);
1546 	/* Failure to probe PTP is not fatal; this channel will just not be
1547 	 * used for anything.
1548 	 * In the case of EPERM, efx_ptp_probe will print its own message (in
1549 	 * efx_ptp_get_attributes()), so we don't need to.
1550 	 */
1551 	if (rc && rc != -EPERM)
1552 		netif_warn(efx, drv, efx->net_dev,
1553 			   "Failed to probe PTP, rc=%d\n", rc);
1554 	return 0;
1555 }
1556 
efx_ptp_remove(struct efx_nic * efx)1557 static void efx_ptp_remove(struct efx_nic *efx)
1558 {
1559 	if (!efx->ptp_data)
1560 		return;
1561 
1562 	(void)efx_ptp_disable(efx);
1563 
1564 	cancel_work_sync(&efx->ptp_data->work);
1565 	if (efx->ptp_data->pps_workwq)
1566 		cancel_work_sync(&efx->ptp_data->pps_work);
1567 
1568 	skb_queue_purge(&efx->ptp_data->rxq);
1569 	skb_queue_purge(&efx->ptp_data->txq);
1570 
1571 	if (efx->ptp_data->phc_clock) {
1572 		destroy_workqueue(efx->ptp_data->pps_workwq);
1573 		ptp_clock_unregister(efx->ptp_data->phc_clock);
1574 	}
1575 
1576 	destroy_workqueue(efx->ptp_data->workwq);
1577 
1578 	efx_siena_free_buffer(efx, &efx->ptp_data->start);
1579 	kfree(efx->ptp_data);
1580 	efx->ptp_data = NULL;
1581 }
1582 
efx_ptp_remove_channel(struct efx_channel * channel)1583 static void efx_ptp_remove_channel(struct efx_channel *channel)
1584 {
1585 	efx_ptp_remove(channel->efx);
1586 }
1587 
efx_ptp_get_channel_name(struct efx_channel * channel,char * buf,size_t len)1588 static void efx_ptp_get_channel_name(struct efx_channel *channel,
1589 				     char *buf, size_t len)
1590 {
1591 	snprintf(buf, len, "%s-ptp", channel->efx->name);
1592 }
1593 
1594 /* Determine whether this packet should be processed by the PTP module
1595  * or transmitted conventionally.
1596  */
efx_siena_ptp_is_ptp_tx(struct efx_nic * efx,struct sk_buff * skb)1597 bool efx_siena_ptp_is_ptp_tx(struct efx_nic *efx, struct sk_buff *skb)
1598 {
1599 	return efx->ptp_data &&
1600 		efx->ptp_data->enabled &&
1601 		skb->len >= PTP_MIN_LENGTH &&
1602 		skb->len <= MC_CMD_PTP_IN_TRANSMIT_PACKET_MAXNUM &&
1603 		likely(skb->protocol == htons(ETH_P_IP)) &&
1604 		skb_transport_header_was_set(skb) &&
1605 		skb_network_header_len(skb) >= sizeof(struct iphdr) &&
1606 		ip_hdr(skb)->protocol == IPPROTO_UDP &&
1607 		skb_headlen(skb) >=
1608 		skb_transport_offset(skb) + sizeof(struct udphdr) &&
1609 		udp_hdr(skb)->dest == htons(PTP_EVENT_PORT);
1610 }
1611 
1612 /* Receive a PTP packet.  Packets are queued until the arrival of
1613  * the receive timestamp from the MC - this will probably occur after the
1614  * packet arrival because of the processing in the MC.
1615  */
efx_ptp_rx(struct efx_channel * channel,struct sk_buff * skb)1616 static bool efx_ptp_rx(struct efx_channel *channel, struct sk_buff *skb)
1617 {
1618 	struct efx_nic *efx = channel->efx;
1619 	struct efx_ptp_data *ptp = efx->ptp_data;
1620 	struct efx_ptp_match *match = (struct efx_ptp_match *)skb->cb;
1621 	u8 *match_data_012, *match_data_345;
1622 	unsigned int version;
1623 	u8 *data;
1624 
1625 	match->expiry = jiffies + msecs_to_jiffies(PKT_EVENT_LIFETIME_MS);
1626 
1627 	/* Correct version? */
1628 	if (ptp->mode == MC_CMD_PTP_MODE_V1) {
1629 		if (!pskb_may_pull(skb, PTP_V1_MIN_LENGTH)) {
1630 			return false;
1631 		}
1632 		data = skb->data;
1633 		version = ntohs(*(__be16 *)&data[PTP_V1_VERSION_OFFSET]);
1634 		if (version != PTP_VERSION_V1) {
1635 			return false;
1636 		}
1637 
1638 		/* PTP V1 uses all six bytes of the UUID to match the packet
1639 		 * to the timestamp
1640 		 */
1641 		match_data_012 = data + PTP_V1_UUID_OFFSET;
1642 		match_data_345 = data + PTP_V1_UUID_OFFSET + 3;
1643 	} else {
1644 		if (!pskb_may_pull(skb, PTP_V2_MIN_LENGTH)) {
1645 			return false;
1646 		}
1647 		data = skb->data;
1648 		version = data[PTP_V2_VERSION_OFFSET];
1649 		if ((version & PTP_VERSION_V2_MASK) != PTP_VERSION_V2) {
1650 			return false;
1651 		}
1652 
1653 		/* The original V2 implementation uses bytes 2-7 of
1654 		 * the UUID to match the packet to the timestamp. This
1655 		 * discards two of the bytes of the MAC address used
1656 		 * to create the UUID (SF bug 33070).  The PTP V2
1657 		 * enhanced mode fixes this issue and uses bytes 0-2
1658 		 * and byte 5-7 of the UUID.
1659 		 */
1660 		match_data_345 = data + PTP_V2_UUID_OFFSET + 5;
1661 		if (ptp->mode == MC_CMD_PTP_MODE_V2) {
1662 			match_data_012 = data + PTP_V2_UUID_OFFSET + 2;
1663 		} else {
1664 			match_data_012 = data + PTP_V2_UUID_OFFSET + 0;
1665 			BUG_ON(ptp->mode != MC_CMD_PTP_MODE_V2_ENHANCED);
1666 		}
1667 	}
1668 
1669 	/* Does this packet require timestamping? */
1670 	if (ntohs(*(__be16 *)&data[PTP_DPORT_OFFSET]) == PTP_EVENT_PORT) {
1671 		match->state = PTP_PACKET_STATE_UNMATCHED;
1672 
1673 		/* We expect the sequence number to be in the same position in
1674 		 * the packet for PTP V1 and V2
1675 		 */
1676 		BUILD_BUG_ON(PTP_V1_SEQUENCE_OFFSET != PTP_V2_SEQUENCE_OFFSET);
1677 		BUILD_BUG_ON(PTP_V1_SEQUENCE_LENGTH != PTP_V2_SEQUENCE_LENGTH);
1678 
1679 		/* Extract UUID/Sequence information */
1680 		match->words[0] = (match_data_012[0]         |
1681 				   (match_data_012[1] << 8)  |
1682 				   (match_data_012[2] << 16) |
1683 				   (match_data_345[0] << 24));
1684 		match->words[1] = (match_data_345[1]         |
1685 				   (match_data_345[2] << 8)  |
1686 				   (data[PTP_V1_SEQUENCE_OFFSET +
1687 					 PTP_V1_SEQUENCE_LENGTH - 1] <<
1688 				    16));
1689 	} else {
1690 		match->state = PTP_PACKET_STATE_MATCH_UNWANTED;
1691 	}
1692 
1693 	skb_queue_tail(&ptp->rxq, skb);
1694 	queue_work(ptp->workwq, &ptp->work);
1695 
1696 	return true;
1697 }
1698 
1699 /* Transmit a PTP packet.  This has to be transmitted by the MC
1700  * itself, through an MCDI call.  MCDI calls aren't permitted
1701  * in the transmit path so defer the actual transmission to a suitable worker.
1702  */
efx_siena_ptp_tx(struct efx_nic * efx,struct sk_buff * skb)1703 int efx_siena_ptp_tx(struct efx_nic *efx, struct sk_buff *skb)
1704 {
1705 	struct efx_ptp_data *ptp = efx->ptp_data;
1706 
1707 	skb_queue_tail(&ptp->txq, skb);
1708 
1709 	if ((udp_hdr(skb)->dest == htons(PTP_EVENT_PORT)) &&
1710 	    (skb->len <= MC_CMD_PTP_IN_TRANSMIT_PACKET_MAXNUM))
1711 		efx_xmit_hwtstamp_pending(skb);
1712 	queue_work(ptp->workwq, &ptp->work);
1713 
1714 	return NETDEV_TX_OK;
1715 }
1716 
efx_siena_ptp_get_mode(struct efx_nic * efx)1717 int efx_siena_ptp_get_mode(struct efx_nic *efx)
1718 {
1719 	return efx->ptp_data->mode;
1720 }
1721 
efx_siena_ptp_change_mode(struct efx_nic * efx,bool enable_wanted,unsigned int new_mode)1722 int efx_siena_ptp_change_mode(struct efx_nic *efx, bool enable_wanted,
1723 			      unsigned int new_mode)
1724 {
1725 	if ((enable_wanted != efx->ptp_data->enabled) ||
1726 	    (enable_wanted && (efx->ptp_data->mode != new_mode))) {
1727 		int rc = 0;
1728 
1729 		if (enable_wanted) {
1730 			/* Change of mode requires disable */
1731 			if (efx->ptp_data->enabled &&
1732 			    (efx->ptp_data->mode != new_mode)) {
1733 				efx->ptp_data->enabled = false;
1734 				rc = efx_ptp_stop(efx);
1735 				if (rc != 0)
1736 					return rc;
1737 			}
1738 
1739 			/* Set new operating mode and establish
1740 			 * baseline synchronisation, which must
1741 			 * succeed.
1742 			 */
1743 			efx->ptp_data->mode = new_mode;
1744 			if (netif_running(efx->net_dev))
1745 				rc = efx_ptp_start(efx);
1746 			if (rc == 0) {
1747 				rc = efx_ptp_synchronize(efx,
1748 							 PTP_SYNC_ATTEMPTS * 2);
1749 				if (rc != 0)
1750 					efx_ptp_stop(efx);
1751 			}
1752 		} else {
1753 			rc = efx_ptp_stop(efx);
1754 		}
1755 
1756 		if (rc != 0)
1757 			return rc;
1758 
1759 		efx->ptp_data->enabled = enable_wanted;
1760 	}
1761 
1762 	return 0;
1763 }
1764 
efx_ptp_ts_init(struct efx_nic * efx,struct kernel_hwtstamp_config * init)1765 static int efx_ptp_ts_init(struct efx_nic *efx,
1766 			   struct kernel_hwtstamp_config *init)
1767 {
1768 	int rc;
1769 
1770 	if ((init->tx_type != HWTSTAMP_TX_OFF) &&
1771 	    (init->tx_type != HWTSTAMP_TX_ON))
1772 		return -ERANGE;
1773 
1774 	rc = efx->type->ptp_set_ts_config(efx, init);
1775 	if (rc)
1776 		return rc;
1777 
1778 	efx->ptp_data->config = *init;
1779 	return 0;
1780 }
1781 
efx_siena_ptp_get_ts_info(struct efx_nic * efx,struct kernel_ethtool_ts_info * ts_info)1782 void efx_siena_ptp_get_ts_info(struct efx_nic *efx,
1783 			       struct kernel_ethtool_ts_info *ts_info)
1784 {
1785 	struct efx_ptp_data *ptp = efx->ptp_data;
1786 	struct efx_nic *primary = efx->primary;
1787 
1788 	ASSERT_RTNL();
1789 
1790 	if (!ptp)
1791 		return;
1792 
1793 	ts_info->so_timestamping |= (SOF_TIMESTAMPING_TX_HARDWARE |
1794 				     SOF_TIMESTAMPING_RX_HARDWARE |
1795 				     SOF_TIMESTAMPING_RAW_HARDWARE);
1796 	if (primary && primary->ptp_data && primary->ptp_data->phc_clock)
1797 		ts_info->phc_index =
1798 			ptp_clock_index(primary->ptp_data->phc_clock);
1799 	ts_info->tx_types = 1 << HWTSTAMP_TX_OFF | 1 << HWTSTAMP_TX_ON;
1800 	ts_info->rx_filters = ptp->efx->type->hwtstamp_filters;
1801 }
1802 
efx_siena_ptp_set_ts_config(struct efx_nic * efx,struct kernel_hwtstamp_config * config,struct netlink_ext_ack __always_unused * extack)1803 int efx_siena_ptp_set_ts_config(struct efx_nic *efx,
1804 				struct kernel_hwtstamp_config *config,
1805 				struct netlink_ext_ack __always_unused *extack)
1806 {
1807 	/* Not a PTP enabled port */
1808 	if (!efx->ptp_data)
1809 		return -EOPNOTSUPP;
1810 
1811 	return efx_ptp_ts_init(efx, config);
1812 }
1813 
efx_siena_ptp_get_ts_config(struct efx_nic * efx,struct kernel_hwtstamp_config * config)1814 int efx_siena_ptp_get_ts_config(struct efx_nic *efx,
1815 				struct kernel_hwtstamp_config *config)
1816 {
1817 	/* Not a PTP enabled port */
1818 	if (!efx->ptp_data)
1819 		return -EOPNOTSUPP;
1820 
1821 	*config = efx->ptp_data->config;
1822 	return 0;
1823 }
1824 
ptp_event_failure(struct efx_nic * efx,int expected_frag_len)1825 static void ptp_event_failure(struct efx_nic *efx, int expected_frag_len)
1826 {
1827 	struct efx_ptp_data *ptp = efx->ptp_data;
1828 
1829 	netif_err(efx, hw, efx->net_dev,
1830 		"PTP unexpected event length: got %d expected %d\n",
1831 		ptp->evt_frag_idx, expected_frag_len);
1832 	ptp->reset_required = true;
1833 	queue_work(ptp->workwq, &ptp->work);
1834 }
1835 
1836 /* Process a completed receive event.  Put it on the event queue and
1837  * start worker thread.  This is required because event and their
1838  * correspoding packets may come in either order.
1839  */
ptp_event_rx(struct efx_nic * efx,struct efx_ptp_data * ptp)1840 static void ptp_event_rx(struct efx_nic *efx, struct efx_ptp_data *ptp)
1841 {
1842 	struct efx_ptp_event_rx *evt = NULL;
1843 
1844 	if (WARN_ON_ONCE(ptp->rx_ts_inline))
1845 		return;
1846 
1847 	if (ptp->evt_frag_idx != 3) {
1848 		ptp_event_failure(efx, 3);
1849 		return;
1850 	}
1851 
1852 	spin_lock_bh(&ptp->evt_lock);
1853 	if (!list_empty(&ptp->evt_free_list)) {
1854 		evt = list_first_entry(&ptp->evt_free_list,
1855 				       struct efx_ptp_event_rx, link);
1856 		list_del(&evt->link);
1857 
1858 		evt->seq0 = EFX_QWORD_FIELD(ptp->evt_frags[2], MCDI_EVENT_DATA);
1859 		evt->seq1 = (EFX_QWORD_FIELD(ptp->evt_frags[2],
1860 					     MCDI_EVENT_SRC)        |
1861 			     (EFX_QWORD_FIELD(ptp->evt_frags[1],
1862 					      MCDI_EVENT_SRC) << 8) |
1863 			     (EFX_QWORD_FIELD(ptp->evt_frags[0],
1864 					      MCDI_EVENT_SRC) << 16));
1865 		evt->hwtimestamp = efx->ptp_data->nic_to_kernel_time(
1866 			EFX_QWORD_FIELD(ptp->evt_frags[0], MCDI_EVENT_DATA),
1867 			EFX_QWORD_FIELD(ptp->evt_frags[1], MCDI_EVENT_DATA),
1868 			ptp->ts_corrections.ptp_rx);
1869 		evt->expiry = jiffies + msecs_to_jiffies(PKT_EVENT_LIFETIME_MS);
1870 		list_add_tail(&evt->link, &ptp->evt_list);
1871 
1872 		queue_work(ptp->workwq, &ptp->work);
1873 	} else if (net_ratelimit()) {
1874 		/* Log a rate-limited warning message. */
1875 		netif_err(efx, rx_err, efx->net_dev, "PTP event queue overflow\n");
1876 	}
1877 	spin_unlock_bh(&ptp->evt_lock);
1878 }
1879 
ptp_event_fault(struct efx_nic * efx,struct efx_ptp_data * ptp)1880 static void ptp_event_fault(struct efx_nic *efx, struct efx_ptp_data *ptp)
1881 {
1882 	int code = EFX_QWORD_FIELD(ptp->evt_frags[0], MCDI_EVENT_DATA);
1883 	if (ptp->evt_frag_idx != 1) {
1884 		ptp_event_failure(efx, 1);
1885 		return;
1886 	}
1887 
1888 	netif_err(efx, hw, efx->net_dev, "PTP error %d\n", code);
1889 }
1890 
ptp_event_pps(struct efx_nic * efx,struct efx_ptp_data * ptp)1891 static void ptp_event_pps(struct efx_nic *efx, struct efx_ptp_data *ptp)
1892 {
1893 	if (ptp->nic_ts_enabled)
1894 		queue_work(ptp->pps_workwq, &ptp->pps_work);
1895 }
1896 
efx_siena_ptp_event(struct efx_nic * efx,efx_qword_t * ev)1897 void efx_siena_ptp_event(struct efx_nic *efx, efx_qword_t *ev)
1898 {
1899 	struct efx_ptp_data *ptp = efx->ptp_data;
1900 	int code = EFX_QWORD_FIELD(*ev, MCDI_EVENT_CODE);
1901 
1902 	if (!ptp) {
1903 		if (!efx->ptp_warned) {
1904 			netif_warn(efx, drv, efx->net_dev,
1905 				   "Received PTP event but PTP not set up\n");
1906 			efx->ptp_warned = true;
1907 		}
1908 		return;
1909 	}
1910 
1911 	if (!ptp->enabled)
1912 		return;
1913 
1914 	if (ptp->evt_frag_idx == 0) {
1915 		ptp->evt_code = code;
1916 	} else if (ptp->evt_code != code) {
1917 		netif_err(efx, hw, efx->net_dev,
1918 			  "PTP out of sequence event %d\n", code);
1919 		ptp->evt_frag_idx = 0;
1920 	}
1921 
1922 	ptp->evt_frags[ptp->evt_frag_idx++] = *ev;
1923 	if (!MCDI_EVENT_FIELD(*ev, CONT)) {
1924 		/* Process resulting event */
1925 		switch (code) {
1926 		case MCDI_EVENT_CODE_PTP_RX:
1927 			ptp_event_rx(efx, ptp);
1928 			break;
1929 		case MCDI_EVENT_CODE_PTP_FAULT:
1930 			ptp_event_fault(efx, ptp);
1931 			break;
1932 		case MCDI_EVENT_CODE_PTP_PPS:
1933 			ptp_event_pps(efx, ptp);
1934 			break;
1935 		default:
1936 			netif_err(efx, hw, efx->net_dev,
1937 				  "PTP unknown event %d\n", code);
1938 			break;
1939 		}
1940 		ptp->evt_frag_idx = 0;
1941 	} else if (MAX_EVENT_FRAGS == ptp->evt_frag_idx) {
1942 		netif_err(efx, hw, efx->net_dev,
1943 			  "PTP too many event fragments\n");
1944 		ptp->evt_frag_idx = 0;
1945 	}
1946 }
1947 
efx_siena_time_sync_event(struct efx_channel * channel,efx_qword_t * ev)1948 void efx_siena_time_sync_event(struct efx_channel *channel, efx_qword_t *ev)
1949 {
1950 	struct efx_nic *efx = channel->efx;
1951 	struct efx_ptp_data *ptp = efx->ptp_data;
1952 
1953 	/* When extracting the sync timestamp minor value, we should discard
1954 	 * the least significant two bits. These are not required in order
1955 	 * to reconstruct full-range timestamps and they are optionally used
1956 	 * to report status depending on the options supplied when subscribing
1957 	 * for sync events.
1958 	 */
1959 	channel->sync_timestamp_major = MCDI_EVENT_FIELD(*ev, PTP_TIME_MAJOR);
1960 	channel->sync_timestamp_minor =
1961 		(MCDI_EVENT_FIELD(*ev, PTP_TIME_MINOR_MS_8BITS) & 0xFC)
1962 			<< ptp->nic_time.sync_event_minor_shift;
1963 
1964 	/* if sync events have been disabled then we want to silently ignore
1965 	 * this event, so throw away result.
1966 	 */
1967 	(void) cmpxchg(&channel->sync_events_state, SYNC_EVENTS_REQUESTED,
1968 		       SYNC_EVENTS_VALID);
1969 }
1970 
efx_rx_buf_timestamp_minor(struct efx_nic * efx,const u8 * eh)1971 static inline u32 efx_rx_buf_timestamp_minor(struct efx_nic *efx, const u8 *eh)
1972 {
1973 #if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS)
1974 	return __le32_to_cpup((const __le32 *)(eh + efx->rx_packet_ts_offset));
1975 #else
1976 	const u8 *data = eh + efx->rx_packet_ts_offset;
1977 	return (u32)data[0]       |
1978 	       (u32)data[1] << 8  |
1979 	       (u32)data[2] << 16 |
1980 	       (u32)data[3] << 24;
1981 #endif
1982 }
1983 
__efx_siena_rx_skb_attach_timestamp(struct efx_channel * channel,struct sk_buff * skb)1984 void __efx_siena_rx_skb_attach_timestamp(struct efx_channel *channel,
1985 					 struct sk_buff *skb)
1986 {
1987 	struct efx_nic *efx = channel->efx;
1988 	struct efx_ptp_data *ptp = efx->ptp_data;
1989 	u32 pkt_timestamp_major, pkt_timestamp_minor;
1990 	u32 diff, carry;
1991 	struct skb_shared_hwtstamps *timestamps;
1992 
1993 	if (channel->sync_events_state != SYNC_EVENTS_VALID)
1994 		return;
1995 
1996 	pkt_timestamp_minor = efx_rx_buf_timestamp_minor(efx, skb_mac_header(skb));
1997 
1998 	/* get the difference between the packet and sync timestamps,
1999 	 * modulo one second
2000 	 */
2001 	diff = pkt_timestamp_minor - channel->sync_timestamp_minor;
2002 	if (pkt_timestamp_minor < channel->sync_timestamp_minor)
2003 		diff += ptp->nic_time.minor_max;
2004 
2005 	/* do we roll over a second boundary and need to carry the one? */
2006 	carry = (channel->sync_timestamp_minor >= ptp->nic_time.minor_max - diff) ?
2007 		1 : 0;
2008 
2009 	if (diff <= ptp->nic_time.sync_event_diff_max) {
2010 		/* packet is ahead of the sync event by a quarter of a second or
2011 		 * less (allowing for fuzz)
2012 		 */
2013 		pkt_timestamp_major = channel->sync_timestamp_major + carry;
2014 	} else if (diff >= ptp->nic_time.sync_event_diff_min) {
2015 		/* packet is behind the sync event but within the fuzz factor.
2016 		 * This means the RX packet and sync event crossed as they were
2017 		 * placed on the event queue, which can sometimes happen.
2018 		 */
2019 		pkt_timestamp_major = channel->sync_timestamp_major - 1 + carry;
2020 	} else {
2021 		/* it's outside tolerance in both directions. this might be
2022 		 * indicative of us missing sync events for some reason, so
2023 		 * we'll call it an error rather than risk giving a bogus
2024 		 * timestamp.
2025 		 */
2026 		netif_vdbg(efx, drv, efx->net_dev,
2027 			  "packet timestamp %x too far from sync event %x:%x\n",
2028 			  pkt_timestamp_minor, channel->sync_timestamp_major,
2029 			  channel->sync_timestamp_minor);
2030 		return;
2031 	}
2032 
2033 	/* attach the timestamps to the skb */
2034 	timestamps = skb_hwtstamps(skb);
2035 	timestamps->hwtstamp =
2036 		ptp->nic_to_kernel_time(pkt_timestamp_major,
2037 					pkt_timestamp_minor,
2038 					ptp->ts_corrections.general_rx);
2039 }
2040 
efx_phc_adjfine(struct ptp_clock_info * ptp,long scaled_ppm)2041 static int efx_phc_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
2042 {
2043 	struct efx_ptp_data *ptp_data = container_of(ptp,
2044 						     struct efx_ptp_data,
2045 						     phc_clock_info);
2046 	s32 delta = scaled_ppm_to_ppb(scaled_ppm);
2047 	struct efx_nic *efx = ptp_data->efx;
2048 	MCDI_DECLARE_BUF(inadj, MC_CMD_PTP_IN_ADJUST_LEN);
2049 	s64 adjustment_ns;
2050 	int rc;
2051 
2052 	if (delta > MAX_PPB)
2053 		delta = MAX_PPB;
2054 	else if (delta < -MAX_PPB)
2055 		delta = -MAX_PPB;
2056 
2057 	/* Convert ppb to fixed point ns taking care to round correctly. */
2058 	adjustment_ns = ((s64)delta * PPB_SCALE_WORD +
2059 			 (1 << (ptp_data->adjfreq_ppb_shift - 1))) >>
2060 			ptp_data->adjfreq_ppb_shift;
2061 
2062 	MCDI_SET_DWORD(inadj, PTP_IN_OP, MC_CMD_PTP_OP_ADJUST);
2063 	MCDI_SET_DWORD(inadj, PTP_IN_PERIPH_ID, 0);
2064 	MCDI_SET_QWORD(inadj, PTP_IN_ADJUST_FREQ, adjustment_ns);
2065 	MCDI_SET_DWORD(inadj, PTP_IN_ADJUST_SECONDS, 0);
2066 	MCDI_SET_DWORD(inadj, PTP_IN_ADJUST_NANOSECONDS, 0);
2067 	rc = efx_siena_mcdi_rpc(efx, MC_CMD_PTP, inadj, sizeof(inadj),
2068 				NULL, 0, NULL);
2069 	if (rc != 0)
2070 		return rc;
2071 
2072 	ptp_data->current_adjfreq = adjustment_ns;
2073 	return 0;
2074 }
2075 
efx_phc_adjtime(struct ptp_clock_info * ptp,s64 delta)2076 static int efx_phc_adjtime(struct ptp_clock_info *ptp, s64 delta)
2077 {
2078 	u32 nic_major, nic_minor;
2079 	struct efx_ptp_data *ptp_data = container_of(ptp,
2080 						     struct efx_ptp_data,
2081 						     phc_clock_info);
2082 	struct efx_nic *efx = ptp_data->efx;
2083 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_ADJUST_LEN);
2084 
2085 	efx->ptp_data->ns_to_nic_time(delta, &nic_major, &nic_minor);
2086 
2087 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_ADJUST);
2088 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
2089 	MCDI_SET_QWORD(inbuf, PTP_IN_ADJUST_FREQ, ptp_data->current_adjfreq);
2090 	MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_MAJOR, nic_major);
2091 	MCDI_SET_DWORD(inbuf, PTP_IN_ADJUST_MINOR, nic_minor);
2092 	return efx_siena_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
2093 				  NULL, 0, NULL);
2094 }
2095 
efx_phc_gettime(struct ptp_clock_info * ptp,struct timespec64 * ts)2096 static int efx_phc_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
2097 {
2098 	struct efx_ptp_data *ptp_data = container_of(ptp,
2099 						     struct efx_ptp_data,
2100 						     phc_clock_info);
2101 	struct efx_nic *efx = ptp_data->efx;
2102 	MCDI_DECLARE_BUF(inbuf, MC_CMD_PTP_IN_READ_NIC_TIME_LEN);
2103 	MCDI_DECLARE_BUF(outbuf, MC_CMD_PTP_OUT_READ_NIC_TIME_LEN);
2104 	int rc;
2105 	ktime_t kt;
2106 
2107 	MCDI_SET_DWORD(inbuf, PTP_IN_OP, MC_CMD_PTP_OP_READ_NIC_TIME);
2108 	MCDI_SET_DWORD(inbuf, PTP_IN_PERIPH_ID, 0);
2109 
2110 	rc = efx_siena_mcdi_rpc(efx, MC_CMD_PTP, inbuf, sizeof(inbuf),
2111 				outbuf, sizeof(outbuf), NULL);
2112 	if (rc != 0)
2113 		return rc;
2114 
2115 	kt = ptp_data->nic_to_kernel_time(
2116 		MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_MAJOR),
2117 		MCDI_DWORD(outbuf, PTP_OUT_READ_NIC_TIME_MINOR), 0);
2118 	*ts = ktime_to_timespec64(kt);
2119 	return 0;
2120 }
2121 
efx_phc_settime(struct ptp_clock_info * ptp,const struct timespec64 * e_ts)2122 static int efx_phc_settime(struct ptp_clock_info *ptp,
2123 			   const struct timespec64 *e_ts)
2124 {
2125 	/* Get the current NIC time, efx_phc_gettime.
2126 	 * Subtract from the desired time to get the offset
2127 	 * call efx_phc_adjtime with the offset
2128 	 */
2129 	int rc;
2130 	struct timespec64 time_now;
2131 	struct timespec64 delta;
2132 
2133 	rc = efx_phc_gettime(ptp, &time_now);
2134 	if (rc != 0)
2135 		return rc;
2136 
2137 	delta = timespec64_sub(*e_ts, time_now);
2138 
2139 	rc = efx_phc_adjtime(ptp, timespec64_to_ns(&delta));
2140 	if (rc != 0)
2141 		return rc;
2142 
2143 	return 0;
2144 }
2145 
efx_phc_enable(struct ptp_clock_info * ptp,struct ptp_clock_request * request,int enable)2146 static int efx_phc_enable(struct ptp_clock_info *ptp,
2147 			  struct ptp_clock_request *request,
2148 			  int enable)
2149 {
2150 	struct efx_ptp_data *ptp_data = container_of(ptp,
2151 						     struct efx_ptp_data,
2152 						     phc_clock_info);
2153 	if (request->type != PTP_CLK_REQ_PPS)
2154 		return -EOPNOTSUPP;
2155 
2156 	ptp_data->nic_ts_enabled = !!enable;
2157 	return 0;
2158 }
2159 
2160 static const struct efx_channel_type efx_ptp_channel_type = {
2161 	.handle_no_channel	= efx_ptp_handle_no_channel,
2162 	.pre_probe		= efx_ptp_probe_channel,
2163 	.post_remove		= efx_ptp_remove_channel,
2164 	.get_name		= efx_ptp_get_channel_name,
2165 	/* no copy operation; there is no need to reallocate this channel */
2166 	.receive_skb		= efx_ptp_rx,
2167 	.want_txqs		= efx_ptp_want_txqs,
2168 	.keep_eventq		= false,
2169 };
2170 
efx_siena_ptp_defer_probe_with_channel(struct efx_nic * efx)2171 void efx_siena_ptp_defer_probe_with_channel(struct efx_nic *efx)
2172 {
2173 	/* Check whether PTP is implemented on this NIC.  The DISABLE
2174 	 * operation will succeed if and only if it is implemented.
2175 	 */
2176 	if (efx_ptp_disable(efx) == 0)
2177 		efx->extra_channel_type[EFX_EXTRA_CHANNEL_PTP] =
2178 			&efx_ptp_channel_type;
2179 }
2180 
efx_siena_ptp_start_datapath(struct efx_nic * efx)2181 void efx_siena_ptp_start_datapath(struct efx_nic *efx)
2182 {
2183 	if (efx_ptp_restart(efx))
2184 		netif_err(efx, drv, efx->net_dev, "Failed to restart PTP.\n");
2185 	/* re-enable timestamping if it was previously enabled */
2186 	if (efx->type->ptp_set_ts_sync_events)
2187 		efx->type->ptp_set_ts_sync_events(efx, true, true);
2188 }
2189 
efx_siena_ptp_stop_datapath(struct efx_nic * efx)2190 void efx_siena_ptp_stop_datapath(struct efx_nic *efx)
2191 {
2192 	/* temporarily disable timestamping */
2193 	if (efx->type->ptp_set_ts_sync_events)
2194 		efx->type->ptp_set_ts_sync_events(efx, false, true);
2195 	efx_ptp_stop(efx);
2196 }
2197