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1 /*******************************************************************************
2 
3   Intel 10 Gigabit PCI Express Linux driver
4   Copyright(c) 1999 - 2016 Intel Corporation.
5 
6   This program is free software; you can redistribute it and/or modify it
7   under the terms and conditions of the GNU General Public License,
8   version 2, as published by the Free Software Foundation.
9 
10   This program is distributed in the hope it will be useful, but WITHOUT
11   ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12   FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13   more details.
14 
15   You should have received a copy of the GNU General Public License along with
16   this program; if not, write to the Free Software Foundation, Inc.,
17   51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
18 
19   The full GNU General Public License is included in this distribution in
20   the file called "COPYING".
21 
22   Contact Information:
23   Linux NICS <linux.nics@intel.com>
24   e1000-devel Mailing List <e1000-devel@lists.sourceforge.net>
25   Intel Corporation, 5200 N.E. Elam Young Parkway, Hillsboro, OR 97124-6497
26 
27 *******************************************************************************/
28 #include "ixgbe.h"
29 #include <linux/ptp_classify.h>
30 #include <linux/clocksource.h>
31 
32 /*
33  * The 82599 and the X540 do not have true 64bit nanosecond scale
34  * counter registers. Instead, SYSTIME is defined by a fixed point
35  * system which allows the user to define the scale counter increment
36  * value at every level change of the oscillator driving the SYSTIME
37  * value. For both devices the TIMINCA:IV field defines this
38  * increment. On the X540 device, 31 bits are provided. However on the
39  * 82599 only provides 24 bits. The time unit is determined by the
40  * clock frequency of the oscillator in combination with the TIMINCA
41  * register. When these devices link at 10Gb the oscillator has a
42  * period of 6.4ns. In order to convert the scale counter into
43  * nanoseconds the cyclecounter and timecounter structures are
44  * used. The SYSTIME registers need to be converted to ns values by use
45  * of only a right shift (division by power of 2). The following math
46  * determines the largest incvalue that will fit into the available
47  * bits in the TIMINCA register.
48  *
49  * PeriodWidth: Number of bits to store the clock period
50  * MaxWidth: The maximum width value of the TIMINCA register
51  * Period: The clock period for the oscillator
52  * round(): discard the fractional portion of the calculation
53  *
54  * Period * [ 2 ^ ( MaxWidth - PeriodWidth ) ]
55  *
56  * For the X540, MaxWidth is 31 bits, and the base period is 6.4 ns
57  * For the 82599, MaxWidth is 24 bits, and the base period is 6.4 ns
58  *
59  * The period also changes based on the link speed:
60  * At 10Gb link or no link, the period remains the same.
61  * At 1Gb link, the period is multiplied by 10. (64ns)
62  * At 100Mb link, the period is multiplied by 100. (640ns)
63  *
64  * The calculated value allows us to right shift the SYSTIME register
65  * value in order to quickly convert it into a nanosecond clock,
66  * while allowing for the maximum possible adjustment value.
67  *
68  * These diagrams are only for the 10Gb link period
69  *
70  *           SYSTIMEH            SYSTIMEL
71  *       +--------------+  +--------------+
72  * X540  |      32      |  | 1 | 3 |  28  |
73  *       *--------------+  +--------------+
74  *        \________ 36 bits ______/  fract
75  *
76  *       +--------------+  +--------------+
77  * 82599 |      32      |  | 8 | 3 |  21  |
78  *       *--------------+  +--------------+
79  *        \________ 43 bits ______/  fract
80  *
81  * The 36 bit X540 SYSTIME overflows every
82  *   2^36 * 10^-9 / 60 = 1.14 minutes or 69 seconds
83  *
84  * The 43 bit 82599 SYSTIME overflows every
85  *   2^43 * 10^-9 / 3600 = 2.4 hours
86  */
87 #define IXGBE_INCVAL_10GB 0x66666666
88 #define IXGBE_INCVAL_1GB  0x40000000
89 #define IXGBE_INCVAL_100  0x50000000
90 
91 #define IXGBE_INCVAL_SHIFT_10GB  28
92 #define IXGBE_INCVAL_SHIFT_1GB   24
93 #define IXGBE_INCVAL_SHIFT_100   21
94 
95 #define IXGBE_INCVAL_SHIFT_82599 7
96 #define IXGBE_INCPER_SHIFT_82599 24
97 
98 #define IXGBE_OVERFLOW_PERIOD    (HZ * 30)
99 #define IXGBE_PTP_TX_TIMEOUT     (HZ * 15)
100 
101 /* half of a one second clock period, for use with PPS signal. We have to use
102  * this instead of something pre-defined like IXGBE_PTP_PPS_HALF_SECOND, in
103  * order to force at least 64bits of precision for shifting
104  */
105 #define IXGBE_PTP_PPS_HALF_SECOND 500000000ULL
106 
107 /* In contrast, the X550 controller has two registers, SYSTIMEH and SYSTIMEL
108  * which contain measurements of seconds and nanoseconds respectively. This
109  * matches the standard linux representation of time in the kernel. In addition,
110  * the X550 also has a SYSTIMER register which represents residue, or
111  * subnanosecond overflow adjustments. To control clock adjustment, the TIMINCA
112  * register is used, but it is unlike the X540 and 82599 devices. TIMINCA
113  * represents units of 2^-32 nanoseconds, and uses 31 bits for this, with the
114  * high bit representing whether the adjustent is positive or negative. Every
115  * clock cycle, the X550 will add 12.5 ns + TIMINCA which can result in a range
116  * of 12 to 13 nanoseconds adjustment. Unlike the 82599 and X540 devices, the
117  * X550's clock for purposes of SYSTIME generation is constant and not dependent
118  * on the link speed.
119  *
120  *           SYSTIMEH           SYSTIMEL        SYSTIMER
121  *       +--------------+  +--------------+  +-------------+
122  * X550  |      32      |  |      32      |  |     32      |
123  *       *--------------+  +--------------+  +-------------+
124  *       \____seconds___/   \_nanoseconds_/  \__2^-32 ns__/
125  *
126  * This results in a full 96 bits to represent the clock, with 32 bits for
127  * seconds, 32 bits for nanoseconds (largest value is 0d999999999 or just under
128  * 1 second) and an additional 32 bits to measure sub nanosecond adjustments for
129  * underflow of adjustments.
130  *
131  * The 32 bits of seconds for the X550 overflows every
132  *   2^32 / ( 365.25 * 24 * 60 * 60 ) = ~136 years.
133  *
134  * In order to adjust the clock frequency for the X550, the TIMINCA register is
135  * provided. This register represents a + or minus nearly 0.5 ns adjustment to
136  * the base frequency. It is measured in 2^-32 ns units, with the high bit being
137  * the sign bit. This register enables software to calculate frequency
138  * adjustments and apply them directly to the clock rate.
139  *
140  * The math for converting ppb into TIMINCA values is fairly straightforward.
141  *   TIMINCA value = ( Base_Frequency * ppb ) / 1000000000ULL
142  *
143  * This assumes that ppb is never high enough to create a value bigger than
144  * TIMINCA's 31 bits can store. This is ensured by the stack. Calculating this
145  * value is also simple.
146  *   Max ppb = ( Max Adjustment / Base Frequency ) / 1000000000ULL
147  *
148  * For the X550, the Max adjustment is +/- 0.5 ns, and the base frequency is
149  * 12.5 nanoseconds. This means that the Max ppb is 39999999
150  *   Note: We subtract one in order to ensure no overflow, because the TIMINCA
151  *         register can only hold slightly under 0.5 nanoseconds.
152  *
153  * Because TIMINCA is measured in 2^-32 ns units, we have to convert 12.5 ns
154  * into 2^-32 units, which is
155  *
156  *  12.5 * 2^32 = C80000000
157  *
158  * Some revisions of hardware have a faster base frequency than the registers
159  * were defined for. To fix this, we use a timecounter structure with the
160  * proper mult and shift to convert the cycles into nanoseconds of time.
161  */
162 #define IXGBE_X550_BASE_PERIOD 0xC80000000ULL
163 #define INCVALUE_MASK	0x7FFFFFFF
164 #define ISGN		0x80000000
165 #define MAX_TIMADJ	0x7FFFFFFF
166 
167 /**
168  * ixgbe_ptp_setup_sdp_x540
169  * @hw: the hardware private structure
170  *
171  * this function enables or disables the clock out feature on SDP0 for
172  * the X540 device. It will create a 1second periodic output that can
173  * be used as the PPS (via an interrupt).
174  *
175  * It calculates when the systime will be on an exact second, and then
176  * aligns the start of the PPS signal to that value. The shift is
177  * necessary because it can change based on the link speed.
178  */
ixgbe_ptp_setup_sdp_x540(struct ixgbe_adapter * adapter)179 static void ixgbe_ptp_setup_sdp_x540(struct ixgbe_adapter *adapter)
180 {
181 	struct ixgbe_hw *hw = &adapter->hw;
182 	int shift = adapter->hw_cc.shift;
183 	u32 esdp, tsauxc, clktiml, clktimh, trgttiml, trgttimh, rem;
184 	u64 ns = 0, clock_edge = 0;
185 
186 	/* disable the pin first */
187 	IXGBE_WRITE_REG(hw, IXGBE_TSAUXC, 0x0);
188 	IXGBE_WRITE_FLUSH(hw);
189 
190 	if (!(adapter->flags2 & IXGBE_FLAG2_PTP_PPS_ENABLED))
191 		return;
192 
193 	esdp = IXGBE_READ_REG(hw, IXGBE_ESDP);
194 
195 	/* enable the SDP0 pin as output, and connected to the
196 	 * native function for Timesync (ClockOut)
197 	 */
198 	esdp |= IXGBE_ESDP_SDP0_DIR |
199 		IXGBE_ESDP_SDP0_NATIVE;
200 
201 	/* enable the Clock Out feature on SDP0, and allow
202 	 * interrupts to occur when the pin changes
203 	 */
204 	tsauxc = IXGBE_TSAUXC_EN_CLK |
205 		 IXGBE_TSAUXC_SYNCLK |
206 		 IXGBE_TSAUXC_SDP0_INT;
207 
208 	/* clock period (or pulse length) */
209 	clktiml = (u32)(IXGBE_PTP_PPS_HALF_SECOND << shift);
210 	clktimh = (u32)((IXGBE_PTP_PPS_HALF_SECOND << shift) >> 32);
211 
212 	/* Account for the cyclecounter wrap-around value by
213 	 * using the converted ns value of the current time to
214 	 * check for when the next aligned second would occur.
215 	 */
216 	clock_edge |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIML);
217 	clock_edge |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIMH) << 32;
218 	ns = timecounter_cyc2time(&adapter->hw_tc, clock_edge);
219 
220 	div_u64_rem(ns, IXGBE_PTP_PPS_HALF_SECOND, &rem);
221 	clock_edge += ((IXGBE_PTP_PPS_HALF_SECOND - (u64)rem) << shift);
222 
223 	/* specify the initial clock start time */
224 	trgttiml = (u32)clock_edge;
225 	trgttimh = (u32)(clock_edge >> 32);
226 
227 	IXGBE_WRITE_REG(hw, IXGBE_CLKTIML, clktiml);
228 	IXGBE_WRITE_REG(hw, IXGBE_CLKTIMH, clktimh);
229 	IXGBE_WRITE_REG(hw, IXGBE_TRGTTIML0, trgttiml);
230 	IXGBE_WRITE_REG(hw, IXGBE_TRGTTIMH0, trgttimh);
231 
232 	IXGBE_WRITE_REG(hw, IXGBE_ESDP, esdp);
233 	IXGBE_WRITE_REG(hw, IXGBE_TSAUXC, tsauxc);
234 
235 	IXGBE_WRITE_FLUSH(hw);
236 }
237 
238 /**
239  * ixgbe_ptp_read_X550 - read cycle counter value
240  * @hw_cc: cyclecounter structure
241  *
242  * This function reads SYSTIME registers. It is called by the cyclecounter
243  * structure to convert from internal representation into nanoseconds. We need
244  * this for X550 since some skews do not have expected clock frequency and
245  * result of SYSTIME is 32bits of "billions of cycles" and 32 bits of
246  * "cycles", rather than seconds and nanoseconds.
247  */
ixgbe_ptp_read_X550(const struct cyclecounter * hw_cc)248 static cycle_t ixgbe_ptp_read_X550(const struct cyclecounter *hw_cc)
249 {
250 	struct ixgbe_adapter *adapter =
251 			container_of(hw_cc, struct ixgbe_adapter, hw_cc);
252 	struct ixgbe_hw *hw = &adapter->hw;
253 	struct timespec64 ts;
254 
255 	/* storage is 32 bits of 'billions of cycles' and 32 bits of 'cycles'.
256 	 * Some revisions of hardware run at a higher frequency and so the
257 	 * cycles are not guaranteed to be nanoseconds. The timespec64 created
258 	 * here is used for its math/conversions but does not necessarily
259 	 * represent nominal time.
260 	 *
261 	 * It should be noted that this cyclecounter will overflow at a
262 	 * non-bitmask field since we have to convert our billions of cycles
263 	 * into an actual cycles count. This results in some possible weird
264 	 * situations at high cycle counter stamps. However given that 32 bits
265 	 * of "seconds" is ~138 years this isn't a problem. Even at the
266 	 * increased frequency of some revisions, this is still ~103 years.
267 	 * Since the SYSTIME values start at 0 and we never write them, it is
268 	 * highly unlikely for the cyclecounter to overflow in practice.
269 	 */
270 	IXGBE_READ_REG(hw, IXGBE_SYSTIMR);
271 	ts.tv_nsec = IXGBE_READ_REG(hw, IXGBE_SYSTIML);
272 	ts.tv_sec = IXGBE_READ_REG(hw, IXGBE_SYSTIMH);
273 
274 	return (u64)timespec64_to_ns(&ts);
275 }
276 
277 /**
278  * ixgbe_ptp_read_82599 - read raw cycle counter (to be used by time counter)
279  * @cc: the cyclecounter structure
280  *
281  * this function reads the cyclecounter registers and is called by the
282  * cyclecounter structure used to construct a ns counter from the
283  * arbitrary fixed point registers
284  */
ixgbe_ptp_read_82599(const struct cyclecounter * cc)285 static cycle_t ixgbe_ptp_read_82599(const struct cyclecounter *cc)
286 {
287 	struct ixgbe_adapter *adapter =
288 		container_of(cc, struct ixgbe_adapter, hw_cc);
289 	struct ixgbe_hw *hw = &adapter->hw;
290 	u64 stamp = 0;
291 
292 	stamp |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIML);
293 	stamp |= (u64)IXGBE_READ_REG(hw, IXGBE_SYSTIMH) << 32;
294 
295 	return stamp;
296 }
297 
298 /**
299  * ixgbe_ptp_convert_to_hwtstamp - convert register value to hw timestamp
300  * @adapter: private adapter structure
301  * @hwtstamp: stack timestamp structure
302  * @systim: unsigned 64bit system time value
303  *
304  * We need to convert the adapter's RX/TXSTMP registers into a hwtstamp value
305  * which can be used by the stack's ptp functions.
306  *
307  * The lock is used to protect consistency of the cyclecounter and the SYSTIME
308  * registers. However, it does not need to protect against the Rx or Tx
309  * timestamp registers, as there can't be a new timestamp until the old one is
310  * unlatched by reading.
311  *
312  * In addition to the timestamp in hardware, some controllers need a software
313  * overflow cyclecounter, and this function takes this into account as well.
314  **/
ixgbe_ptp_convert_to_hwtstamp(struct ixgbe_adapter * adapter,struct skb_shared_hwtstamps * hwtstamp,u64 timestamp)315 static void ixgbe_ptp_convert_to_hwtstamp(struct ixgbe_adapter *adapter,
316 					  struct skb_shared_hwtstamps *hwtstamp,
317 					  u64 timestamp)
318 {
319 	unsigned long flags;
320 	struct timespec64 systime;
321 	u64 ns;
322 
323 	memset(hwtstamp, 0, sizeof(*hwtstamp));
324 
325 	switch (adapter->hw.mac.type) {
326 	/* X550 and later hardware supposedly represent time using a seconds
327 	 * and nanoseconds counter, instead of raw 64bits nanoseconds. We need
328 	 * to convert the timestamp into cycles before it can be fed to the
329 	 * cyclecounter. We need an actual cyclecounter because some revisions
330 	 * of hardware run at a higher frequency and thus the counter does
331 	 * not represent seconds/nanoseconds. Instead it can be thought of as
332 	 * cycles and billions of cycles.
333 	 */
334 	case ixgbe_mac_X550:
335 	case ixgbe_mac_X550EM_x:
336 	case ixgbe_mac_x550em_a:
337 		/* Upper 32 bits represent billions of cycles, lower 32 bits
338 		 * represent cycles. However, we use timespec64_to_ns for the
339 		 * correct math even though the units haven't been corrected
340 		 * yet.
341 		 */
342 		systime.tv_sec = timestamp >> 32;
343 		systime.tv_nsec = timestamp & 0xFFFFFFFF;
344 
345 		timestamp = timespec64_to_ns(&systime);
346 		break;
347 	default:
348 		break;
349 	}
350 
351 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
352 	ns = timecounter_cyc2time(&adapter->hw_tc, timestamp);
353 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
354 
355 	hwtstamp->hwtstamp = ns_to_ktime(ns);
356 }
357 
358 /**
359  * ixgbe_ptp_adjfreq_82599
360  * @ptp: the ptp clock structure
361  * @ppb: parts per billion adjustment from base
362  *
363  * adjust the frequency of the ptp cycle counter by the
364  * indicated ppb from the base frequency.
365  */
ixgbe_ptp_adjfreq_82599(struct ptp_clock_info * ptp,s32 ppb)366 static int ixgbe_ptp_adjfreq_82599(struct ptp_clock_info *ptp, s32 ppb)
367 {
368 	struct ixgbe_adapter *adapter =
369 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
370 	struct ixgbe_hw *hw = &adapter->hw;
371 	u64 freq, incval;
372 	u32 diff;
373 	int neg_adj = 0;
374 
375 	if (ppb < 0) {
376 		neg_adj = 1;
377 		ppb = -ppb;
378 	}
379 
380 	smp_mb();
381 	incval = ACCESS_ONCE(adapter->base_incval);
382 
383 	freq = incval;
384 	freq *= ppb;
385 	diff = div_u64(freq, 1000000000ULL);
386 
387 	incval = neg_adj ? (incval - diff) : (incval + diff);
388 
389 	switch (hw->mac.type) {
390 	case ixgbe_mac_X540:
391 		if (incval > 0xFFFFFFFFULL)
392 			e_dev_warn("PTP ppb adjusted SYSTIME rate overflowed!\n");
393 		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA, (u32)incval);
394 		break;
395 	case ixgbe_mac_82599EB:
396 		if (incval > 0x00FFFFFFULL)
397 			e_dev_warn("PTP ppb adjusted SYSTIME rate overflowed!\n");
398 		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA,
399 				BIT(IXGBE_INCPER_SHIFT_82599) |
400 				((u32)incval & 0x00FFFFFFUL));
401 		break;
402 	default:
403 		break;
404 	}
405 
406 	return 0;
407 }
408 
409 /**
410  * ixgbe_ptp_adjfreq_X550
411  * @ptp: the ptp clock structure
412  * @ppb: parts per billion adjustment from base
413  *
414  * adjust the frequency of the SYSTIME registers by the indicated ppb from base
415  * frequency
416  */
ixgbe_ptp_adjfreq_X550(struct ptp_clock_info * ptp,s32 ppb)417 static int ixgbe_ptp_adjfreq_X550(struct ptp_clock_info *ptp, s32 ppb)
418 {
419 	struct ixgbe_adapter *adapter =
420 			container_of(ptp, struct ixgbe_adapter, ptp_caps);
421 	struct ixgbe_hw *hw = &adapter->hw;
422 	int neg_adj = 0;
423 	u64 rate = IXGBE_X550_BASE_PERIOD;
424 	u32 inca;
425 
426 	if (ppb < 0) {
427 		neg_adj = 1;
428 		ppb = -ppb;
429 	}
430 	rate *= ppb;
431 	rate = div_u64(rate, 1000000000ULL);
432 
433 	/* warn if rate is too large */
434 	if (rate >= INCVALUE_MASK)
435 		e_dev_warn("PTP ppb adjusted SYSTIME rate overflowed!\n");
436 
437 	inca = rate & INCVALUE_MASK;
438 	if (neg_adj)
439 		inca |= ISGN;
440 
441 	IXGBE_WRITE_REG(hw, IXGBE_TIMINCA, inca);
442 
443 	return 0;
444 }
445 
446 /**
447  * ixgbe_ptp_adjtime
448  * @ptp: the ptp clock structure
449  * @delta: offset to adjust the cycle counter by
450  *
451  * adjust the timer by resetting the timecounter structure.
452  */
ixgbe_ptp_adjtime(struct ptp_clock_info * ptp,s64 delta)453 static int ixgbe_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
454 {
455 	struct ixgbe_adapter *adapter =
456 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
457 	unsigned long flags;
458 
459 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
460 	timecounter_adjtime(&adapter->hw_tc, delta);
461 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
462 
463 	if (adapter->ptp_setup_sdp)
464 		adapter->ptp_setup_sdp(adapter);
465 
466 	return 0;
467 }
468 
469 /**
470  * ixgbe_ptp_gettime
471  * @ptp: the ptp clock structure
472  * @ts: timespec structure to hold the current time value
473  *
474  * read the timecounter and return the correct value on ns,
475  * after converting it into a struct timespec.
476  */
ixgbe_ptp_gettime(struct ptp_clock_info * ptp,struct timespec64 * ts)477 static int ixgbe_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
478 {
479 	struct ixgbe_adapter *adapter =
480 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
481 	unsigned long flags;
482 	u64 ns;
483 
484 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
485 	ns = timecounter_read(&adapter->hw_tc);
486 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
487 
488 	*ts = ns_to_timespec64(ns);
489 
490 	return 0;
491 }
492 
493 /**
494  * ixgbe_ptp_settime
495  * @ptp: the ptp clock structure
496  * @ts: the timespec containing the new time for the cycle counter
497  *
498  * reset the timecounter to use a new base value instead of the kernel
499  * wall timer value.
500  */
ixgbe_ptp_settime(struct ptp_clock_info * ptp,const struct timespec64 * ts)501 static int ixgbe_ptp_settime(struct ptp_clock_info *ptp,
502 			     const struct timespec64 *ts)
503 {
504 	struct ixgbe_adapter *adapter =
505 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
506 	unsigned long flags;
507 	u64 ns = timespec64_to_ns(ts);
508 
509 	/* reset the timecounter */
510 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
511 	timecounter_init(&adapter->hw_tc, &adapter->hw_cc, ns);
512 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
513 
514 	if (adapter->ptp_setup_sdp)
515 		adapter->ptp_setup_sdp(adapter);
516 	return 0;
517 }
518 
519 /**
520  * ixgbe_ptp_feature_enable
521  * @ptp: the ptp clock structure
522  * @rq: the requested feature to change
523  * @on: whether to enable or disable the feature
524  *
525  * enable (or disable) ancillary features of the phc subsystem.
526  * our driver only supports the PPS feature on the X540
527  */
ixgbe_ptp_feature_enable(struct ptp_clock_info * ptp,struct ptp_clock_request * rq,int on)528 static int ixgbe_ptp_feature_enable(struct ptp_clock_info *ptp,
529 				    struct ptp_clock_request *rq, int on)
530 {
531 	struct ixgbe_adapter *adapter =
532 		container_of(ptp, struct ixgbe_adapter, ptp_caps);
533 
534 	/**
535 	 * When PPS is enabled, unmask the interrupt for the ClockOut
536 	 * feature, so that the interrupt handler can send the PPS
537 	 * event when the clock SDP triggers. Clear mask when PPS is
538 	 * disabled
539 	 */
540 	if (rq->type != PTP_CLK_REQ_PPS || !adapter->ptp_setup_sdp)
541 		return -ENOTSUPP;
542 
543 	if (on)
544 		adapter->flags2 |= IXGBE_FLAG2_PTP_PPS_ENABLED;
545 	else
546 		adapter->flags2 &= ~IXGBE_FLAG2_PTP_PPS_ENABLED;
547 
548 	adapter->ptp_setup_sdp(adapter);
549 	return 0;
550 }
551 
552 /**
553  * ixgbe_ptp_check_pps_event
554  * @adapter: the private adapter structure
555  *
556  * This function is called by the interrupt routine when checking for
557  * interrupts. It will check and handle a pps event.
558  */
ixgbe_ptp_check_pps_event(struct ixgbe_adapter * adapter)559 void ixgbe_ptp_check_pps_event(struct ixgbe_adapter *adapter)
560 {
561 	struct ixgbe_hw *hw = &adapter->hw;
562 	struct ptp_clock_event event;
563 
564 	event.type = PTP_CLOCK_PPS;
565 
566 	/* this check is necessary in case the interrupt was enabled via some
567 	 * alternative means (ex. debug_fs). Better to check here than
568 	 * everywhere that calls this function.
569 	 */
570 	if (!adapter->ptp_clock)
571 		return;
572 
573 	switch (hw->mac.type) {
574 	case ixgbe_mac_X540:
575 		ptp_clock_event(adapter->ptp_clock, &event);
576 		break;
577 	default:
578 		break;
579 	}
580 }
581 
582 /**
583  * ixgbe_ptp_overflow_check - watchdog task to detect SYSTIME overflow
584  * @adapter: private adapter struct
585  *
586  * this watchdog task periodically reads the timecounter
587  * in order to prevent missing when the system time registers wrap
588  * around. This needs to be run approximately twice a minute.
589  */
ixgbe_ptp_overflow_check(struct ixgbe_adapter * adapter)590 void ixgbe_ptp_overflow_check(struct ixgbe_adapter *adapter)
591 {
592 	bool timeout = time_is_before_jiffies(adapter->last_overflow_check +
593 					     IXGBE_OVERFLOW_PERIOD);
594 	struct timespec64 ts;
595 
596 	if (timeout) {
597 		ixgbe_ptp_gettime(&adapter->ptp_caps, &ts);
598 		adapter->last_overflow_check = jiffies;
599 	}
600 }
601 
602 /**
603  * ixgbe_ptp_rx_hang - detect error case when Rx timestamp registers latched
604  * @adapter: private network adapter structure
605  *
606  * this watchdog task is scheduled to detect error case where hardware has
607  * dropped an Rx packet that was timestamped when the ring is full. The
608  * particular error is rare but leaves the device in a state unable to timestamp
609  * any future packets.
610  */
ixgbe_ptp_rx_hang(struct ixgbe_adapter * adapter)611 void ixgbe_ptp_rx_hang(struct ixgbe_adapter *adapter)
612 {
613 	struct ixgbe_hw *hw = &adapter->hw;
614 	u32 tsyncrxctl = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
615 	struct ixgbe_ring *rx_ring;
616 	unsigned long rx_event;
617 	int n;
618 
619 	/* if we don't have a valid timestamp in the registers, just update the
620 	 * timeout counter and exit
621 	 */
622 	if (!(tsyncrxctl & IXGBE_TSYNCRXCTL_VALID)) {
623 		adapter->last_rx_ptp_check = jiffies;
624 		return;
625 	}
626 
627 	/* determine the most recent watchdog or rx_timestamp event */
628 	rx_event = adapter->last_rx_ptp_check;
629 	for (n = 0; n < adapter->num_rx_queues; n++) {
630 		rx_ring = adapter->rx_ring[n];
631 		if (time_after(rx_ring->last_rx_timestamp, rx_event))
632 			rx_event = rx_ring->last_rx_timestamp;
633 	}
634 
635 	/* only need to read the high RXSTMP register to clear the lock */
636 	if (time_is_before_jiffies(rx_event + 5 * HZ)) {
637 		IXGBE_READ_REG(hw, IXGBE_RXSTMPH);
638 		adapter->last_rx_ptp_check = jiffies;
639 
640 		adapter->rx_hwtstamp_cleared++;
641 		e_warn(drv, "clearing RX Timestamp hang\n");
642 	}
643 }
644 
645 /**
646  * ixgbe_ptp_clear_tx_timestamp - utility function to clear Tx timestamp state
647  * @adapter: the private adapter structure
648  *
649  * This function should be called whenever the state related to a Tx timestamp
650  * needs to be cleared. This helps ensure that all related bits are reset for
651  * the next Tx timestamp event.
652  */
ixgbe_ptp_clear_tx_timestamp(struct ixgbe_adapter * adapter)653 static void ixgbe_ptp_clear_tx_timestamp(struct ixgbe_adapter *adapter)
654 {
655 	struct ixgbe_hw *hw = &adapter->hw;
656 
657 	IXGBE_READ_REG(hw, IXGBE_TXSTMPH);
658 	if (adapter->ptp_tx_skb) {
659 		dev_kfree_skb_any(adapter->ptp_tx_skb);
660 		adapter->ptp_tx_skb = NULL;
661 	}
662 	clear_bit_unlock(__IXGBE_PTP_TX_IN_PROGRESS, &adapter->state);
663 }
664 
665 /**
666  * ixgbe_ptp_tx_hwtstamp - utility function which checks for TX time stamp
667  * @adapter: the private adapter struct
668  *
669  * if the timestamp is valid, we convert it into the timecounter ns
670  * value, then store that result into the shhwtstamps structure which
671  * is passed up the network stack
672  */
ixgbe_ptp_tx_hwtstamp(struct ixgbe_adapter * adapter)673 static void ixgbe_ptp_tx_hwtstamp(struct ixgbe_adapter *adapter)
674 {
675 	struct ixgbe_hw *hw = &adapter->hw;
676 	struct skb_shared_hwtstamps shhwtstamps;
677 	u64 regval = 0;
678 
679 	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_TXSTMPL);
680 	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_TXSTMPH) << 32;
681 
682 	ixgbe_ptp_convert_to_hwtstamp(adapter, &shhwtstamps, regval);
683 	skb_tstamp_tx(adapter->ptp_tx_skb, &shhwtstamps);
684 
685 	ixgbe_ptp_clear_tx_timestamp(adapter);
686 }
687 
688 /**
689  * ixgbe_ptp_tx_hwtstamp_work
690  * @work: pointer to the work struct
691  *
692  * This work item polls TSYNCTXCTL valid bit to determine when a Tx hardware
693  * timestamp has been taken for the current skb. It is necessary, because the
694  * descriptor's "done" bit does not correlate with the timestamp event.
695  */
ixgbe_ptp_tx_hwtstamp_work(struct work_struct * work)696 static void ixgbe_ptp_tx_hwtstamp_work(struct work_struct *work)
697 {
698 	struct ixgbe_adapter *adapter = container_of(work, struct ixgbe_adapter,
699 						     ptp_tx_work);
700 	struct ixgbe_hw *hw = &adapter->hw;
701 	bool timeout = time_is_before_jiffies(adapter->ptp_tx_start +
702 					      IXGBE_PTP_TX_TIMEOUT);
703 	u32 tsynctxctl;
704 
705 	/* we have to have a valid skb to poll for a timestamp */
706 	if (!adapter->ptp_tx_skb) {
707 		ixgbe_ptp_clear_tx_timestamp(adapter);
708 		return;
709 	}
710 
711 	/* stop polling once we have a valid timestamp */
712 	tsynctxctl = IXGBE_READ_REG(hw, IXGBE_TSYNCTXCTL);
713 	if (tsynctxctl & IXGBE_TSYNCTXCTL_VALID) {
714 		ixgbe_ptp_tx_hwtstamp(adapter);
715 		return;
716 	}
717 
718 	if (timeout) {
719 		ixgbe_ptp_clear_tx_timestamp(adapter);
720 		adapter->tx_hwtstamp_timeouts++;
721 		e_warn(drv, "clearing Tx Timestamp hang\n");
722 	} else {
723 		/* reschedule to keep checking if it's not available yet */
724 		schedule_work(&adapter->ptp_tx_work);
725 	}
726 }
727 
728 /**
729  * ixgbe_ptp_rx_pktstamp - utility function to get RX time stamp from buffer
730  * @q_vector: structure containing interrupt and ring information
731  * @skb: the packet
732  *
733  * This function will be called by the Rx routine of the timestamp for this
734  * packet is stored in the buffer. The value is stored in little endian format
735  * starting at the end of the packet data.
736  */
ixgbe_ptp_rx_pktstamp(struct ixgbe_q_vector * q_vector,struct sk_buff * skb)737 void ixgbe_ptp_rx_pktstamp(struct ixgbe_q_vector *q_vector,
738 			   struct sk_buff *skb)
739 {
740 	__le64 regval;
741 
742 	/* copy the bits out of the skb, and then trim the skb length */
743 	skb_copy_bits(skb, skb->len - IXGBE_TS_HDR_LEN, &regval,
744 		      IXGBE_TS_HDR_LEN);
745 	__pskb_trim(skb, skb->len - IXGBE_TS_HDR_LEN);
746 
747 	/* The timestamp is recorded in little endian format, and is stored at
748 	 * the end of the packet.
749 	 *
750 	 * DWORD: N              N + 1      N + 2
751 	 * Field: End of Packet  SYSTIMH    SYSTIML
752 	 */
753 	ixgbe_ptp_convert_to_hwtstamp(q_vector->adapter, skb_hwtstamps(skb),
754 				      le64_to_cpu(regval));
755 }
756 
757 /**
758  * ixgbe_ptp_rx_rgtstamp - utility function which checks for RX time stamp
759  * @q_vector: structure containing interrupt and ring information
760  * @skb: particular skb to send timestamp with
761  *
762  * if the timestamp is valid, we convert it into the timecounter ns
763  * value, then store that result into the shhwtstamps structure which
764  * is passed up the network stack
765  */
ixgbe_ptp_rx_rgtstamp(struct ixgbe_q_vector * q_vector,struct sk_buff * skb)766 void ixgbe_ptp_rx_rgtstamp(struct ixgbe_q_vector *q_vector,
767 			   struct sk_buff *skb)
768 {
769 	struct ixgbe_adapter *adapter;
770 	struct ixgbe_hw *hw;
771 	u64 regval = 0;
772 	u32 tsyncrxctl;
773 
774 	/* we cannot process timestamps on a ring without a q_vector */
775 	if (!q_vector || !q_vector->adapter)
776 		return;
777 
778 	adapter = q_vector->adapter;
779 	hw = &adapter->hw;
780 
781 	/* Read the tsyncrxctl register afterwards in order to prevent taking an
782 	 * I/O hit on every packet.
783 	 */
784 
785 	tsyncrxctl = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
786 	if (!(tsyncrxctl & IXGBE_TSYNCRXCTL_VALID))
787 		return;
788 
789 	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_RXSTMPL);
790 	regval |= (u64)IXGBE_READ_REG(hw, IXGBE_RXSTMPH) << 32;
791 
792 	ixgbe_ptp_convert_to_hwtstamp(adapter, skb_hwtstamps(skb), regval);
793 }
794 
ixgbe_ptp_get_ts_config(struct ixgbe_adapter * adapter,struct ifreq * ifr)795 int ixgbe_ptp_get_ts_config(struct ixgbe_adapter *adapter, struct ifreq *ifr)
796 {
797 	struct hwtstamp_config *config = &adapter->tstamp_config;
798 
799 	return copy_to_user(ifr->ifr_data, config,
800 			    sizeof(*config)) ? -EFAULT : 0;
801 }
802 
803 /**
804  * ixgbe_ptp_set_timestamp_mode - setup the hardware for the requested mode
805  * @adapter: the private ixgbe adapter structure
806  * @config: the hwtstamp configuration requested
807  *
808  * Outgoing time stamping can be enabled and disabled. Play nice and
809  * disable it when requested, although it shouldn't cause any overhead
810  * when no packet needs it. At most one packet in the queue may be
811  * marked for time stamping, otherwise it would be impossible to tell
812  * for sure to which packet the hardware time stamp belongs.
813  *
814  * Incoming time stamping has to be configured via the hardware
815  * filters. Not all combinations are supported, in particular event
816  * type has to be specified. Matching the kind of event packet is
817  * not supported, with the exception of "all V2 events regardless of
818  * level 2 or 4".
819  *
820  * Since hardware always timestamps Path delay packets when timestamping V2
821  * packets, regardless of the type specified in the register, only use V2
822  * Event mode. This more accurately tells the user what the hardware is going
823  * to do anyways.
824  *
825  * Note: this may modify the hwtstamp configuration towards a more general
826  * mode, if required to support the specifically requested mode.
827  */
ixgbe_ptp_set_timestamp_mode(struct ixgbe_adapter * adapter,struct hwtstamp_config * config)828 static int ixgbe_ptp_set_timestamp_mode(struct ixgbe_adapter *adapter,
829 				 struct hwtstamp_config *config)
830 {
831 	struct ixgbe_hw *hw = &adapter->hw;
832 	u32 tsync_tx_ctl = IXGBE_TSYNCTXCTL_ENABLED;
833 	u32 tsync_rx_ctl = IXGBE_TSYNCRXCTL_ENABLED;
834 	u32 tsync_rx_mtrl = PTP_EV_PORT << 16;
835 	bool is_l2 = false;
836 	u32 regval;
837 
838 	/* reserved for future extensions */
839 	if (config->flags)
840 		return -EINVAL;
841 
842 	switch (config->tx_type) {
843 	case HWTSTAMP_TX_OFF:
844 		tsync_tx_ctl = 0;
845 	case HWTSTAMP_TX_ON:
846 		break;
847 	default:
848 		return -ERANGE;
849 	}
850 
851 	switch (config->rx_filter) {
852 	case HWTSTAMP_FILTER_NONE:
853 		tsync_rx_ctl = 0;
854 		tsync_rx_mtrl = 0;
855 		adapter->flags &= ~(IXGBE_FLAG_RX_HWTSTAMP_ENABLED |
856 				    IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER);
857 		break;
858 	case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
859 		tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_L4_V1;
860 		tsync_rx_mtrl |= IXGBE_RXMTRL_V1_SYNC_MSG;
861 		adapter->flags &= ~(IXGBE_FLAG_RX_HWTSTAMP_ENABLED |
862 				    IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER);
863 		break;
864 	case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
865 		tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_L4_V1;
866 		tsync_rx_mtrl |= IXGBE_RXMTRL_V1_DELAY_REQ_MSG;
867 		adapter->flags &= ~(IXGBE_FLAG_RX_HWTSTAMP_ENABLED |
868 				    IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER);
869 		break;
870 	case HWTSTAMP_FILTER_PTP_V2_EVENT:
871 	case HWTSTAMP_FILTER_PTP_V2_L2_EVENT:
872 	case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
873 	case HWTSTAMP_FILTER_PTP_V2_SYNC:
874 	case HWTSTAMP_FILTER_PTP_V2_L2_SYNC:
875 	case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
876 	case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
877 	case HWTSTAMP_FILTER_PTP_V2_L2_DELAY_REQ:
878 	case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
879 		tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_EVENT_V2;
880 		is_l2 = true;
881 		config->rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
882 		adapter->flags &= ~(IXGBE_FLAG_RX_HWTSTAMP_ENABLED |
883 				    IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER);
884 		break;
885 	case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
886 	case HWTSTAMP_FILTER_ALL:
887 		/* The X550 controller is capable of timestamping all packets,
888 		 * which allows it to accept any filter.
889 		 */
890 		if (hw->mac.type >= ixgbe_mac_X550) {
891 			tsync_rx_ctl |= IXGBE_TSYNCRXCTL_TYPE_ALL;
892 			config->rx_filter = HWTSTAMP_FILTER_ALL;
893 			adapter->flags |= IXGBE_FLAG_RX_HWTSTAMP_ENABLED;
894 			break;
895 		}
896 		/* fall through */
897 	default:
898 		/*
899 		 * register RXMTRL must be set in order to do V1 packets,
900 		 * therefore it is not possible to time stamp both V1 Sync and
901 		 * Delay_Req messages and hardware does not support
902 		 * timestamping all packets => return error
903 		 */
904 		adapter->flags &= ~(IXGBE_FLAG_RX_HWTSTAMP_ENABLED |
905 				    IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER);
906 		config->rx_filter = HWTSTAMP_FILTER_NONE;
907 		return -ERANGE;
908 	}
909 
910 	if (hw->mac.type == ixgbe_mac_82598EB) {
911 		adapter->flags &= ~(IXGBE_FLAG_RX_HWTSTAMP_ENABLED |
912 				    IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER);
913 		if (tsync_rx_ctl | tsync_tx_ctl)
914 			return -ERANGE;
915 		return 0;
916 	}
917 
918 	/* Per-packet timestamping only works if the filter is set to all
919 	 * packets. Since this is desired, always timestamp all packets as long
920 	 * as any Rx filter was configured.
921 	 */
922 	switch (hw->mac.type) {
923 	case ixgbe_mac_X550:
924 	case ixgbe_mac_X550EM_x:
925 	case ixgbe_mac_x550em_a:
926 		/* enable timestamping all packets only if at least some
927 		 * packets were requested. Otherwise, play nice and disable
928 		 * timestamping
929 		 */
930 		if (config->rx_filter == HWTSTAMP_FILTER_NONE)
931 			break;
932 
933 		tsync_rx_ctl = IXGBE_TSYNCRXCTL_ENABLED |
934 			       IXGBE_TSYNCRXCTL_TYPE_ALL |
935 			       IXGBE_TSYNCRXCTL_TSIP_UT_EN;
936 		config->rx_filter = HWTSTAMP_FILTER_ALL;
937 		adapter->flags |= IXGBE_FLAG_RX_HWTSTAMP_ENABLED;
938 		adapter->flags &= ~IXGBE_FLAG_RX_HWTSTAMP_IN_REGISTER;
939 		is_l2 = true;
940 		break;
941 	default:
942 		break;
943 	}
944 
945 	/* define ethertype filter for timestamping L2 packets */
946 	if (is_l2)
947 		IXGBE_WRITE_REG(hw, IXGBE_ETQF(IXGBE_ETQF_FILTER_1588),
948 				(IXGBE_ETQF_FILTER_EN | /* enable filter */
949 				 IXGBE_ETQF_1588 | /* enable timestamping */
950 				 ETH_P_1588));     /* 1588 eth protocol type */
951 	else
952 		IXGBE_WRITE_REG(hw, IXGBE_ETQF(IXGBE_ETQF_FILTER_1588), 0);
953 
954 	/* enable/disable TX */
955 	regval = IXGBE_READ_REG(hw, IXGBE_TSYNCTXCTL);
956 	regval &= ~IXGBE_TSYNCTXCTL_ENABLED;
957 	regval |= tsync_tx_ctl;
958 	IXGBE_WRITE_REG(hw, IXGBE_TSYNCTXCTL, regval);
959 
960 	/* enable/disable RX */
961 	regval = IXGBE_READ_REG(hw, IXGBE_TSYNCRXCTL);
962 	regval &= ~(IXGBE_TSYNCRXCTL_ENABLED | IXGBE_TSYNCRXCTL_TYPE_MASK);
963 	regval |= tsync_rx_ctl;
964 	IXGBE_WRITE_REG(hw, IXGBE_TSYNCRXCTL, regval);
965 
966 	/* define which PTP packets are time stamped */
967 	IXGBE_WRITE_REG(hw, IXGBE_RXMTRL, tsync_rx_mtrl);
968 
969 	IXGBE_WRITE_FLUSH(hw);
970 
971 	/* clear TX/RX time stamp registers, just to be sure */
972 	ixgbe_ptp_clear_tx_timestamp(adapter);
973 	IXGBE_READ_REG(hw, IXGBE_RXSTMPH);
974 
975 	return 0;
976 }
977 
978 /**
979  * ixgbe_ptp_set_ts_config - user entry point for timestamp mode
980  * @adapter: pointer to adapter struct
981  * @ifreq: ioctl data
982  *
983  * Set hardware to requested mode. If unsupported, return an error with no
984  * changes. Otherwise, store the mode for future reference.
985  */
ixgbe_ptp_set_ts_config(struct ixgbe_adapter * adapter,struct ifreq * ifr)986 int ixgbe_ptp_set_ts_config(struct ixgbe_adapter *adapter, struct ifreq *ifr)
987 {
988 	struct hwtstamp_config config;
989 	int err;
990 
991 	if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
992 		return -EFAULT;
993 
994 	err = ixgbe_ptp_set_timestamp_mode(adapter, &config);
995 	if (err)
996 		return err;
997 
998 	/* save these settings for future reference */
999 	memcpy(&adapter->tstamp_config, &config,
1000 	       sizeof(adapter->tstamp_config));
1001 
1002 	return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ?
1003 		-EFAULT : 0;
1004 }
1005 
ixgbe_ptp_link_speed_adjust(struct ixgbe_adapter * adapter,u32 * shift,u32 * incval)1006 static void ixgbe_ptp_link_speed_adjust(struct ixgbe_adapter *adapter,
1007 					u32 *shift, u32 *incval)
1008 {
1009 	/**
1010 	 * Scale the NIC cycle counter by a large factor so that
1011 	 * relatively small corrections to the frequency can be added
1012 	 * or subtracted. The drawbacks of a large factor include
1013 	 * (a) the clock register overflows more quickly, (b) the cycle
1014 	 * counter structure must be able to convert the systime value
1015 	 * to nanoseconds using only a multiplier and a right-shift,
1016 	 * and (c) the value must fit within the timinca register space
1017 	 * => math based on internal DMA clock rate and available bits
1018 	 *
1019 	 * Note that when there is no link, internal DMA clock is same as when
1020 	 * link speed is 10Gb. Set the registers correctly even when link is
1021 	 * down to preserve the clock setting
1022 	 */
1023 	switch (adapter->link_speed) {
1024 	case IXGBE_LINK_SPEED_100_FULL:
1025 		*shift = IXGBE_INCVAL_SHIFT_100;
1026 		*incval = IXGBE_INCVAL_100;
1027 		break;
1028 	case IXGBE_LINK_SPEED_1GB_FULL:
1029 		*shift = IXGBE_INCVAL_SHIFT_1GB;
1030 		*incval = IXGBE_INCVAL_1GB;
1031 		break;
1032 	case IXGBE_LINK_SPEED_10GB_FULL:
1033 	default:
1034 		*shift = IXGBE_INCVAL_SHIFT_10GB;
1035 		*incval = IXGBE_INCVAL_10GB;
1036 		break;
1037 	}
1038 }
1039 
1040 /**
1041  * ixgbe_ptp_start_cyclecounter - create the cycle counter from hw
1042  * @adapter: pointer to the adapter structure
1043  *
1044  * This function should be called to set the proper values for the TIMINCA
1045  * register and tell the cyclecounter structure what the tick rate of SYSTIME
1046  * is. It does not directly modify SYSTIME registers or the timecounter
1047  * structure. It should be called whenever a new TIMINCA value is necessary,
1048  * such as during initialization or when the link speed changes.
1049  */
ixgbe_ptp_start_cyclecounter(struct ixgbe_adapter * adapter)1050 void ixgbe_ptp_start_cyclecounter(struct ixgbe_adapter *adapter)
1051 {
1052 	struct ixgbe_hw *hw = &adapter->hw;
1053 	struct cyclecounter cc;
1054 	unsigned long flags;
1055 	u32 incval = 0;
1056 	u32 tsauxc = 0;
1057 	u32 fuse0 = 0;
1058 
1059 	/* For some of the boards below this mask is technically incorrect.
1060 	 * The timestamp mask overflows at approximately 61bits. However the
1061 	 * particular hardware does not overflow on an even bitmask value.
1062 	 * Instead, it overflows due to conversion of upper 32bits billions of
1063 	 * cycles. Timecounters are not really intended for this purpose so
1064 	 * they do not properly function if the overflow point isn't 2^N-1.
1065 	 * However, the actual SYSTIME values in question take ~138 years to
1066 	 * overflow. In practice this means they won't actually overflow. A
1067 	 * proper fix to this problem would require modification of the
1068 	 * timecounter delta calculations.
1069 	 */
1070 	cc.mask = CLOCKSOURCE_MASK(64);
1071 	cc.mult = 1;
1072 	cc.shift = 0;
1073 
1074 	switch (hw->mac.type) {
1075 	case ixgbe_mac_X550EM_x:
1076 		/* SYSTIME assumes X550EM_x board frequency is 300Mhz, and is
1077 		 * designed to represent seconds and nanoseconds when this is
1078 		 * the case. However, some revisions of hardware have a 400Mhz
1079 		 * clock and we have to compensate for this frequency
1080 		 * variation using corrected mult and shift values.
1081 		 */
1082 		fuse0 = IXGBE_READ_REG(hw, IXGBE_FUSES0_GROUP(0));
1083 		if (!(fuse0 & IXGBE_FUSES0_300MHZ)) {
1084 			cc.mult = 3;
1085 			cc.shift = 2;
1086 		}
1087 		/* fallthrough */
1088 	case ixgbe_mac_x550em_a:
1089 	case ixgbe_mac_X550:
1090 		cc.read = ixgbe_ptp_read_X550;
1091 
1092 		/* enable SYSTIME counter */
1093 		IXGBE_WRITE_REG(hw, IXGBE_SYSTIMR, 0);
1094 		IXGBE_WRITE_REG(hw, IXGBE_SYSTIML, 0);
1095 		IXGBE_WRITE_REG(hw, IXGBE_SYSTIMH, 0);
1096 		tsauxc = IXGBE_READ_REG(hw, IXGBE_TSAUXC);
1097 		IXGBE_WRITE_REG(hw, IXGBE_TSAUXC,
1098 				tsauxc & ~IXGBE_TSAUXC_DISABLE_SYSTIME);
1099 		IXGBE_WRITE_REG(hw, IXGBE_TSIM, IXGBE_TSIM_TXTS);
1100 		IXGBE_WRITE_REG(hw, IXGBE_EIMS, IXGBE_EIMS_TIMESYNC);
1101 
1102 		IXGBE_WRITE_FLUSH(hw);
1103 		break;
1104 	case ixgbe_mac_X540:
1105 		cc.read = ixgbe_ptp_read_82599;
1106 
1107 		ixgbe_ptp_link_speed_adjust(adapter, &cc.shift, &incval);
1108 		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA, incval);
1109 		break;
1110 	case ixgbe_mac_82599EB:
1111 		cc.read = ixgbe_ptp_read_82599;
1112 
1113 		ixgbe_ptp_link_speed_adjust(adapter, &cc.shift, &incval);
1114 		incval >>= IXGBE_INCVAL_SHIFT_82599;
1115 		cc.shift -= IXGBE_INCVAL_SHIFT_82599;
1116 		IXGBE_WRITE_REG(hw, IXGBE_TIMINCA,
1117 				BIT(IXGBE_INCPER_SHIFT_82599) | incval);
1118 		break;
1119 	default:
1120 		/* other devices aren't supported */
1121 		return;
1122 	}
1123 
1124 	/* update the base incval used to calculate frequency adjustment */
1125 	ACCESS_ONCE(adapter->base_incval) = incval;
1126 	smp_mb();
1127 
1128 	/* need lock to prevent incorrect read while modifying cyclecounter */
1129 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
1130 	memcpy(&adapter->hw_cc, &cc, sizeof(adapter->hw_cc));
1131 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
1132 }
1133 
1134 /**
1135  * ixgbe_ptp_reset
1136  * @adapter: the ixgbe private board structure
1137  *
1138  * When the MAC resets, all the hardware bits for timesync are reset. This
1139  * function is used to re-enable the device for PTP based on current settings.
1140  * We do lose the current clock time, so just reset the cyclecounter to the
1141  * system real clock time.
1142  *
1143  * This function will maintain hwtstamp_config settings, and resets the SDP
1144  * output if it was enabled.
1145  */
ixgbe_ptp_reset(struct ixgbe_adapter * adapter)1146 void ixgbe_ptp_reset(struct ixgbe_adapter *adapter)
1147 {
1148 	struct ixgbe_hw *hw = &adapter->hw;
1149 	unsigned long flags;
1150 
1151 	/* reset the hardware timestamping mode */
1152 	ixgbe_ptp_set_timestamp_mode(adapter, &adapter->tstamp_config);
1153 
1154 	/* 82598 does not support PTP */
1155 	if (hw->mac.type == ixgbe_mac_82598EB)
1156 		return;
1157 
1158 	ixgbe_ptp_start_cyclecounter(adapter);
1159 
1160 	spin_lock_irqsave(&adapter->tmreg_lock, flags);
1161 	timecounter_init(&adapter->hw_tc, &adapter->hw_cc,
1162 			 ktime_to_ns(ktime_get_real()));
1163 	spin_unlock_irqrestore(&adapter->tmreg_lock, flags);
1164 
1165 	adapter->last_overflow_check = jiffies;
1166 
1167 	/* Now that the shift has been calculated and the systime
1168 	 * registers reset, (re-)enable the Clock out feature
1169 	 */
1170 	if (adapter->ptp_setup_sdp)
1171 		adapter->ptp_setup_sdp(adapter);
1172 }
1173 
1174 /**
1175  * ixgbe_ptp_create_clock
1176  * @adapter: the ixgbe private adapter structure
1177  *
1178  * This function performs setup of the user entry point function table and
1179  * initializes the PTP clock device, which is used to access the clock-like
1180  * features of the PTP core. It will be called by ixgbe_ptp_init, and may
1181  * reuse a previously initialized clock (such as during a suspend/resume
1182  * cycle).
1183  */
ixgbe_ptp_create_clock(struct ixgbe_adapter * adapter)1184 static long ixgbe_ptp_create_clock(struct ixgbe_adapter *adapter)
1185 {
1186 	struct net_device *netdev = adapter->netdev;
1187 	long err;
1188 
1189 	/* do nothing if we already have a clock device */
1190 	if (!IS_ERR_OR_NULL(adapter->ptp_clock))
1191 		return 0;
1192 
1193 	switch (adapter->hw.mac.type) {
1194 	case ixgbe_mac_X540:
1195 		snprintf(adapter->ptp_caps.name,
1196 			 sizeof(adapter->ptp_caps.name),
1197 			 "%s", netdev->name);
1198 		adapter->ptp_caps.owner = THIS_MODULE;
1199 		adapter->ptp_caps.max_adj = 250000000;
1200 		adapter->ptp_caps.n_alarm = 0;
1201 		adapter->ptp_caps.n_ext_ts = 0;
1202 		adapter->ptp_caps.n_per_out = 0;
1203 		adapter->ptp_caps.pps = 1;
1204 		adapter->ptp_caps.adjfreq = ixgbe_ptp_adjfreq_82599;
1205 		adapter->ptp_caps.adjtime = ixgbe_ptp_adjtime;
1206 		adapter->ptp_caps.gettime64 = ixgbe_ptp_gettime;
1207 		adapter->ptp_caps.settime64 = ixgbe_ptp_settime;
1208 		adapter->ptp_caps.enable = ixgbe_ptp_feature_enable;
1209 		adapter->ptp_setup_sdp = ixgbe_ptp_setup_sdp_x540;
1210 		break;
1211 	case ixgbe_mac_82599EB:
1212 		snprintf(adapter->ptp_caps.name,
1213 			 sizeof(adapter->ptp_caps.name),
1214 			 "%s", netdev->name);
1215 		adapter->ptp_caps.owner = THIS_MODULE;
1216 		adapter->ptp_caps.max_adj = 250000000;
1217 		adapter->ptp_caps.n_alarm = 0;
1218 		adapter->ptp_caps.n_ext_ts = 0;
1219 		adapter->ptp_caps.n_per_out = 0;
1220 		adapter->ptp_caps.pps = 0;
1221 		adapter->ptp_caps.adjfreq = ixgbe_ptp_adjfreq_82599;
1222 		adapter->ptp_caps.adjtime = ixgbe_ptp_adjtime;
1223 		adapter->ptp_caps.gettime64 = ixgbe_ptp_gettime;
1224 		adapter->ptp_caps.settime64 = ixgbe_ptp_settime;
1225 		adapter->ptp_caps.enable = ixgbe_ptp_feature_enable;
1226 		break;
1227 	case ixgbe_mac_X550:
1228 	case ixgbe_mac_X550EM_x:
1229 	case ixgbe_mac_x550em_a:
1230 		snprintf(adapter->ptp_caps.name, 16, "%s", netdev->name);
1231 		adapter->ptp_caps.owner = THIS_MODULE;
1232 		adapter->ptp_caps.max_adj = 30000000;
1233 		adapter->ptp_caps.n_alarm = 0;
1234 		adapter->ptp_caps.n_ext_ts = 0;
1235 		adapter->ptp_caps.n_per_out = 0;
1236 		adapter->ptp_caps.pps = 0;
1237 		adapter->ptp_caps.adjfreq = ixgbe_ptp_adjfreq_X550;
1238 		adapter->ptp_caps.adjtime = ixgbe_ptp_adjtime;
1239 		adapter->ptp_caps.gettime64 = ixgbe_ptp_gettime;
1240 		adapter->ptp_caps.settime64 = ixgbe_ptp_settime;
1241 		adapter->ptp_caps.enable = ixgbe_ptp_feature_enable;
1242 		adapter->ptp_setup_sdp = NULL;
1243 		break;
1244 	default:
1245 		adapter->ptp_clock = NULL;
1246 		adapter->ptp_setup_sdp = NULL;
1247 		return -EOPNOTSUPP;
1248 	}
1249 
1250 	adapter->ptp_clock = ptp_clock_register(&adapter->ptp_caps,
1251 						&adapter->pdev->dev);
1252 	if (IS_ERR(adapter->ptp_clock)) {
1253 		err = PTR_ERR(adapter->ptp_clock);
1254 		adapter->ptp_clock = NULL;
1255 		e_dev_err("ptp_clock_register failed\n");
1256 		return err;
1257 	} else if (adapter->ptp_clock)
1258 		e_dev_info("registered PHC device on %s\n", netdev->name);
1259 
1260 	/* set default timestamp mode to disabled here. We do this in
1261 	 * create_clock instead of init, because we don't want to override the
1262 	 * previous settings during a resume cycle.
1263 	 */
1264 	adapter->tstamp_config.rx_filter = HWTSTAMP_FILTER_NONE;
1265 	adapter->tstamp_config.tx_type = HWTSTAMP_TX_OFF;
1266 
1267 	return 0;
1268 }
1269 
1270 /**
1271  * ixgbe_ptp_init
1272  * @adapter: the ixgbe private adapter structure
1273  *
1274  * This function performs the required steps for enabling PTP
1275  * support. If PTP support has already been loaded it simply calls the
1276  * cyclecounter init routine and exits.
1277  */
ixgbe_ptp_init(struct ixgbe_adapter * adapter)1278 void ixgbe_ptp_init(struct ixgbe_adapter *adapter)
1279 {
1280 	/* initialize the spin lock first since we can't control when a user
1281 	 * will call the entry functions once we have initialized the clock
1282 	 * device
1283 	 */
1284 	spin_lock_init(&adapter->tmreg_lock);
1285 
1286 	/* obtain a PTP device, or re-use an existing device */
1287 	if (ixgbe_ptp_create_clock(adapter))
1288 		return;
1289 
1290 	/* we have a clock so we can initialize work now */
1291 	INIT_WORK(&adapter->ptp_tx_work, ixgbe_ptp_tx_hwtstamp_work);
1292 
1293 	/* reset the PTP related hardware bits */
1294 	ixgbe_ptp_reset(adapter);
1295 
1296 	/* enter the IXGBE_PTP_RUNNING state */
1297 	set_bit(__IXGBE_PTP_RUNNING, &adapter->state);
1298 
1299 	return;
1300 }
1301 
1302 /**
1303  * ixgbe_ptp_suspend - stop PTP work items
1304  * @ adapter: pointer to adapter struct
1305  *
1306  * this function suspends PTP activity, and prevents more PTP work from being
1307  * generated, but does not destroy the PTP clock device.
1308  */
ixgbe_ptp_suspend(struct ixgbe_adapter * adapter)1309 void ixgbe_ptp_suspend(struct ixgbe_adapter *adapter)
1310 {
1311 	/* Leave the IXGBE_PTP_RUNNING state. */
1312 	if (!test_and_clear_bit(__IXGBE_PTP_RUNNING, &adapter->state))
1313 		return;
1314 
1315 	adapter->flags2 &= ~IXGBE_FLAG2_PTP_PPS_ENABLED;
1316 	if (adapter->ptp_setup_sdp)
1317 		adapter->ptp_setup_sdp(adapter);
1318 
1319 	/* ensure that we cancel any pending PTP Tx work item in progress */
1320 	cancel_work_sync(&adapter->ptp_tx_work);
1321 	ixgbe_ptp_clear_tx_timestamp(adapter);
1322 }
1323 
1324 /**
1325  * ixgbe_ptp_stop - close the PTP device
1326  * @adapter: pointer to adapter struct
1327  *
1328  * completely destroy the PTP device, should only be called when the device is
1329  * being fully closed.
1330  */
ixgbe_ptp_stop(struct ixgbe_adapter * adapter)1331 void ixgbe_ptp_stop(struct ixgbe_adapter *adapter)
1332 {
1333 	/* first, suspend PTP activity */
1334 	ixgbe_ptp_suspend(adapter);
1335 
1336 	/* disable the PTP clock device */
1337 	if (adapter->ptp_clock) {
1338 		ptp_clock_unregister(adapter->ptp_clock);
1339 		adapter->ptp_clock = NULL;
1340 		e_dev_info("removed PHC on %s\n",
1341 			   adapter->netdev->name);
1342 	}
1343 }
1344