1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Fast Ethernet Controller (ENET) PTP driver for MX6x.
4 *
5 * Copyright (C) 2012 Freescale Semiconductor, Inc.
6 */
7
8 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
9
10 #include <linux/module.h>
11 #include <linux/kernel.h>
12 #include <linux/string.h>
13 #include <linux/ptrace.h>
14 #include <linux/errno.h>
15 #include <linux/ioport.h>
16 #include <linux/slab.h>
17 #include <linux/interrupt.h>
18 #include <linux/pci.h>
19 #include <linux/delay.h>
20 #include <linux/netdevice.h>
21 #include <linux/etherdevice.h>
22 #include <linux/skbuff.h>
23 #include <linux/spinlock.h>
24 #include <linux/workqueue.h>
25 #include <linux/bitops.h>
26 #include <linux/io.h>
27 #include <linux/irq.h>
28 #include <linux/clk.h>
29 #include <linux/platform_device.h>
30 #include <linux/phy.h>
31 #include <linux/fec.h>
32 #include <linux/of.h>
33 #include <linux/of_gpio.h>
34 #include <linux/of_net.h>
35
36 #include "fec.h"
37
38 /* FEC 1588 register bits */
39 #define FEC_T_CTRL_SLAVE 0x00002000
40 #define FEC_T_CTRL_CAPTURE 0x00000800
41 #define FEC_T_CTRL_RESTART 0x00000200
42 #define FEC_T_CTRL_PERIOD_RST 0x00000030
43 #define FEC_T_CTRL_PERIOD_EN 0x00000010
44 #define FEC_T_CTRL_ENABLE 0x00000001
45
46 #define FEC_T_INC_MASK 0x0000007f
47 #define FEC_T_INC_OFFSET 0
48 #define FEC_T_INC_CORR_MASK 0x00007f00
49 #define FEC_T_INC_CORR_OFFSET 8
50
51 #define FEC_T_CTRL_PINPER 0x00000080
52 #define FEC_T_TF0_MASK 0x00000001
53 #define FEC_T_TF0_OFFSET 0
54 #define FEC_T_TF1_MASK 0x00000002
55 #define FEC_T_TF1_OFFSET 1
56 #define FEC_T_TF2_MASK 0x00000004
57 #define FEC_T_TF2_OFFSET 2
58 #define FEC_T_TF3_MASK 0x00000008
59 #define FEC_T_TF3_OFFSET 3
60 #define FEC_T_TDRE_MASK 0x00000001
61 #define FEC_T_TDRE_OFFSET 0
62 #define FEC_T_TMODE_MASK 0x0000003C
63 #define FEC_T_TMODE_OFFSET 2
64 #define FEC_T_TIE_MASK 0x00000040
65 #define FEC_T_TIE_OFFSET 6
66 #define FEC_T_TF_MASK 0x00000080
67 #define FEC_T_TF_OFFSET 7
68
69 #define FEC_ATIME_CTRL 0x400
70 #define FEC_ATIME 0x404
71 #define FEC_ATIME_EVT_OFFSET 0x408
72 #define FEC_ATIME_EVT_PERIOD 0x40c
73 #define FEC_ATIME_CORR 0x410
74 #define FEC_ATIME_INC 0x414
75 #define FEC_TS_TIMESTAMP 0x418
76
77 #define FEC_TGSR 0x604
78 #define FEC_TCSR(n) (0x608 + n * 0x08)
79 #define FEC_TCCR(n) (0x60C + n * 0x08)
80 #define MAX_TIMER_CHANNEL 3
81 #define FEC_TMODE_TOGGLE 0x05
82 #define FEC_HIGH_PULSE 0x0F
83
84 #define FEC_CC_MULT (1 << 31)
85 #define FEC_COUNTER_PERIOD (1 << 31)
86 #define PPS_OUPUT_RELOAD_PERIOD NSEC_PER_SEC
87 #define DEFAULT_PPS_CHANNEL 0
88
89 #define FEC_PTP_MAX_NSEC_PERIOD 4000000000ULL
90 #define FEC_PTP_MAX_NSEC_COUNTER 0x80000000ULL
91
92 /**
93 * fec_ptp_read - read raw cycle counter (to be used by time counter)
94 * @cc: the cyclecounter structure
95 *
96 * this function reads the cyclecounter registers and is called by the
97 * cyclecounter structure used to construct a ns counter from the
98 * arbitrary fixed point registers
99 */
fec_ptp_read(const struct cyclecounter * cc)100 static u64 fec_ptp_read(const struct cyclecounter *cc)
101 {
102 struct fec_enet_private *fep =
103 container_of(cc, struct fec_enet_private, cc);
104 u32 tempval;
105
106 tempval = readl(fep->hwp + FEC_ATIME_CTRL);
107 tempval |= FEC_T_CTRL_CAPTURE;
108 writel(tempval, fep->hwp + FEC_ATIME_CTRL);
109
110 if (fep->quirks & FEC_QUIRK_BUG_CAPTURE)
111 udelay(1);
112
113 return readl(fep->hwp + FEC_ATIME);
114 }
115
116 /**
117 * fec_ptp_enable_pps
118 * @fep: the fec_enet_private structure handle
119 * @enable: enable the channel pps output
120 *
121 * This function enble the PPS ouput on the timer channel.
122 */
fec_ptp_enable_pps(struct fec_enet_private * fep,uint enable)123 static int fec_ptp_enable_pps(struct fec_enet_private *fep, uint enable)
124 {
125 unsigned long flags;
126 u32 val, tempval;
127 struct timespec64 ts;
128 u64 ns;
129
130 spin_lock_irqsave(&fep->tmreg_lock, flags);
131
132 if (fep->pps_enable == enable) {
133 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
134 return 0;
135 }
136
137 if (enable) {
138 /* clear capture or output compare interrupt status if have.
139 */
140 writel(FEC_T_TF_MASK, fep->hwp + FEC_TCSR(fep->pps_channel));
141
142 /* It is recommended to double check the TMODE field in the
143 * TCSR register to be cleared before the first compare counter
144 * is written into TCCR register. Just add a double check.
145 */
146 val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
147 do {
148 val &= ~(FEC_T_TMODE_MASK);
149 writel(val, fep->hwp + FEC_TCSR(fep->pps_channel));
150 val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
151 } while (val & FEC_T_TMODE_MASK);
152
153 /* Dummy read counter to update the counter */
154 timecounter_read(&fep->tc);
155 /* We want to find the first compare event in the next
156 * second point. So we need to know what the ptp time
157 * is now and how many nanoseconds is ahead to get next second.
158 * The remaining nanosecond ahead before the next second would be
159 * NSEC_PER_SEC - ts.tv_nsec. Add the remaining nanoseconds
160 * to current timer would be next second.
161 */
162 tempval = fec_ptp_read(&fep->cc);
163 /* Convert the ptp local counter to 1588 timestamp */
164 ns = timecounter_cyc2time(&fep->tc, tempval);
165 ts = ns_to_timespec64(ns);
166
167 /* The tempval is less than 3 seconds, and so val is less than
168 * 4 seconds. No overflow for 32bit calculation.
169 */
170 val = NSEC_PER_SEC - (u32)ts.tv_nsec + tempval;
171
172 /* Need to consider the situation that the current time is
173 * very close to the second point, which means NSEC_PER_SEC
174 * - ts.tv_nsec is close to be zero(For example 20ns); Since the timer
175 * is still running when we calculate the first compare event, it is
176 * possible that the remaining nanoseonds run out before the compare
177 * counter is calculated and written into TCCR register. To avoid
178 * this possibility, we will set the compare event to be the next
179 * of next second. The current setting is 31-bit timer and wrap
180 * around over 2 seconds. So it is okay to set the next of next
181 * seond for the timer.
182 */
183 val += NSEC_PER_SEC;
184
185 /* We add (2 * NSEC_PER_SEC - (u32)ts.tv_nsec) to current
186 * ptp counter, which maybe cause 32-bit wrap. Since the
187 * (NSEC_PER_SEC - (u32)ts.tv_nsec) is less than 2 second.
188 * We can ensure the wrap will not cause issue. If the offset
189 * is bigger than fep->cc.mask would be a error.
190 */
191 val &= fep->cc.mask;
192 writel(val, fep->hwp + FEC_TCCR(fep->pps_channel));
193
194 /* Calculate the second the compare event timestamp */
195 fep->next_counter = (val + fep->reload_period) & fep->cc.mask;
196
197 /* * Enable compare event when overflow */
198 val = readl(fep->hwp + FEC_ATIME_CTRL);
199 val |= FEC_T_CTRL_PINPER;
200 writel(val, fep->hwp + FEC_ATIME_CTRL);
201
202 /* Compare channel setting. */
203 val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
204 val |= (1 << FEC_T_TF_OFFSET | 1 << FEC_T_TIE_OFFSET);
205 val &= ~(1 << FEC_T_TDRE_OFFSET);
206 val &= ~(FEC_T_TMODE_MASK);
207 val |= (FEC_HIGH_PULSE << FEC_T_TMODE_OFFSET);
208 writel(val, fep->hwp + FEC_TCSR(fep->pps_channel));
209
210 /* Write the second compare event timestamp and calculate
211 * the third timestamp. Refer the TCCR register detail in the spec.
212 */
213 writel(fep->next_counter, fep->hwp + FEC_TCCR(fep->pps_channel));
214 fep->next_counter = (fep->next_counter + fep->reload_period) & fep->cc.mask;
215 } else {
216 writel(0, fep->hwp + FEC_TCSR(fep->pps_channel));
217 }
218
219 fep->pps_enable = enable;
220 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
221
222 return 0;
223 }
224
fec_ptp_pps_perout(struct fec_enet_private * fep)225 static int fec_ptp_pps_perout(struct fec_enet_private *fep)
226 {
227 u32 compare_val, ptp_hc, temp_val;
228 u64 curr_time;
229 unsigned long flags;
230
231 spin_lock_irqsave(&fep->tmreg_lock, flags);
232
233 /* Update time counter */
234 timecounter_read(&fep->tc);
235
236 /* Get the current ptp hardware time counter */
237 ptp_hc = fec_ptp_read(&fep->cc);
238
239 /* Convert the ptp local counter to 1588 timestamp */
240 curr_time = timecounter_cyc2time(&fep->tc, ptp_hc);
241
242 /* If the pps start time less than current time add 100ms, just return.
243 * Because the software might not able to set the comparison time into
244 * the FEC_TCCR register in time and missed the start time.
245 */
246 if (fep->perout_stime < curr_time + 100 * NSEC_PER_MSEC) {
247 dev_err(&fep->pdev->dev, "Current time is too close to the start time!\n");
248 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
249 return -1;
250 }
251
252 compare_val = fep->perout_stime - curr_time + ptp_hc;
253 compare_val &= fep->cc.mask;
254
255 writel(compare_val, fep->hwp + FEC_TCCR(fep->pps_channel));
256 fep->next_counter = (compare_val + fep->reload_period) & fep->cc.mask;
257
258 /* Enable compare event when overflow */
259 temp_val = readl(fep->hwp + FEC_ATIME_CTRL);
260 temp_val |= FEC_T_CTRL_PINPER;
261 writel(temp_val, fep->hwp + FEC_ATIME_CTRL);
262
263 /* Compare channel setting. */
264 temp_val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
265 temp_val |= (1 << FEC_T_TF_OFFSET | 1 << FEC_T_TIE_OFFSET);
266 temp_val &= ~(1 << FEC_T_TDRE_OFFSET);
267 temp_val &= ~(FEC_T_TMODE_MASK);
268 temp_val |= (FEC_TMODE_TOGGLE << FEC_T_TMODE_OFFSET);
269 writel(temp_val, fep->hwp + FEC_TCSR(fep->pps_channel));
270
271 /* Write the second compare event timestamp and calculate
272 * the third timestamp. Refer the TCCR register detail in the spec.
273 */
274 writel(fep->next_counter, fep->hwp + FEC_TCCR(fep->pps_channel));
275 fep->next_counter = (fep->next_counter + fep->reload_period) & fep->cc.mask;
276 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
277
278 return 0;
279 }
280
fec_ptp_pps_perout_handler(struct hrtimer * timer)281 static enum hrtimer_restart fec_ptp_pps_perout_handler(struct hrtimer *timer)
282 {
283 struct fec_enet_private *fep = container_of(timer,
284 struct fec_enet_private, perout_timer);
285
286 fec_ptp_pps_perout(fep);
287
288 return HRTIMER_NORESTART;
289 }
290
291 /**
292 * fec_ptp_start_cyclecounter - create the cycle counter from hw
293 * @ndev: network device
294 *
295 * this function initializes the timecounter and cyclecounter
296 * structures for use in generated a ns counter from the arbitrary
297 * fixed point cycles registers in the hardware.
298 */
fec_ptp_start_cyclecounter(struct net_device * ndev)299 void fec_ptp_start_cyclecounter(struct net_device *ndev)
300 {
301 struct fec_enet_private *fep = netdev_priv(ndev);
302 unsigned long flags;
303 int inc;
304
305 inc = 1000000000 / fep->cycle_speed;
306
307 /* grab the ptp lock */
308 spin_lock_irqsave(&fep->tmreg_lock, flags);
309
310 /* 1ns counter */
311 writel(inc << FEC_T_INC_OFFSET, fep->hwp + FEC_ATIME_INC);
312
313 /* use 31-bit timer counter */
314 writel(FEC_COUNTER_PERIOD, fep->hwp + FEC_ATIME_EVT_PERIOD);
315
316 writel(FEC_T_CTRL_ENABLE | FEC_T_CTRL_PERIOD_RST,
317 fep->hwp + FEC_ATIME_CTRL);
318
319 memset(&fep->cc, 0, sizeof(fep->cc));
320 fep->cc.read = fec_ptp_read;
321 fep->cc.mask = CLOCKSOURCE_MASK(31);
322 fep->cc.shift = 31;
323 fep->cc.mult = FEC_CC_MULT;
324
325 /* reset the ns time counter */
326 timecounter_init(&fep->tc, &fep->cc, 0);
327
328 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
329 }
330
331 /**
332 * fec_ptp_adjfine - adjust ptp cycle frequency
333 * @ptp: the ptp clock structure
334 * @scaled_ppm: scaled parts per million adjustment from base
335 *
336 * Adjust the frequency of the ptp cycle counter by the
337 * indicated amount from the base frequency.
338 *
339 * Scaled parts per million is ppm with a 16-bit binary fractional field.
340 *
341 * Because ENET hardware frequency adjust is complex,
342 * using software method to do that.
343 */
fec_ptp_adjfine(struct ptp_clock_info * ptp,long scaled_ppm)344 static int fec_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
345 {
346 s32 ppb = scaled_ppm_to_ppb(scaled_ppm);
347 unsigned long flags;
348 int neg_adj = 0;
349 u32 i, tmp;
350 u32 corr_inc, corr_period;
351 u32 corr_ns;
352 u64 lhs, rhs;
353
354 struct fec_enet_private *fep =
355 container_of(ptp, struct fec_enet_private, ptp_caps);
356
357 if (ppb == 0)
358 return 0;
359
360 if (ppb < 0) {
361 ppb = -ppb;
362 neg_adj = 1;
363 }
364
365 /* In theory, corr_inc/corr_period = ppb/NSEC_PER_SEC;
366 * Try to find the corr_inc between 1 to fep->ptp_inc to
367 * meet adjustment requirement.
368 */
369 lhs = NSEC_PER_SEC;
370 rhs = (u64)ppb * (u64)fep->ptp_inc;
371 for (i = 1; i <= fep->ptp_inc; i++) {
372 if (lhs >= rhs) {
373 corr_inc = i;
374 corr_period = div_u64(lhs, rhs);
375 break;
376 }
377 lhs += NSEC_PER_SEC;
378 }
379 /* Not found? Set it to high value - double speed
380 * correct in every clock step.
381 */
382 if (i > fep->ptp_inc) {
383 corr_inc = fep->ptp_inc;
384 corr_period = 1;
385 }
386
387 if (neg_adj)
388 corr_ns = fep->ptp_inc - corr_inc;
389 else
390 corr_ns = fep->ptp_inc + corr_inc;
391
392 spin_lock_irqsave(&fep->tmreg_lock, flags);
393
394 tmp = readl(fep->hwp + FEC_ATIME_INC) & FEC_T_INC_MASK;
395 tmp |= corr_ns << FEC_T_INC_CORR_OFFSET;
396 writel(tmp, fep->hwp + FEC_ATIME_INC);
397 corr_period = corr_period > 1 ? corr_period - 1 : corr_period;
398 writel(corr_period, fep->hwp + FEC_ATIME_CORR);
399 /* dummy read to update the timer. */
400 timecounter_read(&fep->tc);
401
402 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
403
404 return 0;
405 }
406
407 /**
408 * fec_ptp_adjtime
409 * @ptp: the ptp clock structure
410 * @delta: offset to adjust the cycle counter by
411 *
412 * adjust the timer by resetting the timecounter structure.
413 */
fec_ptp_adjtime(struct ptp_clock_info * ptp,s64 delta)414 static int fec_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
415 {
416 struct fec_enet_private *fep =
417 container_of(ptp, struct fec_enet_private, ptp_caps);
418 unsigned long flags;
419
420 spin_lock_irqsave(&fep->tmreg_lock, flags);
421 timecounter_adjtime(&fep->tc, delta);
422 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
423
424 return 0;
425 }
426
427 /**
428 * fec_ptp_gettime
429 * @ptp: the ptp clock structure
430 * @ts: timespec structure to hold the current time value
431 *
432 * read the timecounter and return the correct value on ns,
433 * after converting it into a struct timespec.
434 */
fec_ptp_gettime(struct ptp_clock_info * ptp,struct timespec64 * ts)435 static int fec_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
436 {
437 struct fec_enet_private *fep =
438 container_of(ptp, struct fec_enet_private, ptp_caps);
439 u64 ns;
440 unsigned long flags;
441
442 mutex_lock(&fep->ptp_clk_mutex);
443 /* Check the ptp clock */
444 if (!fep->ptp_clk_on) {
445 mutex_unlock(&fep->ptp_clk_mutex);
446 return -EINVAL;
447 }
448 spin_lock_irqsave(&fep->tmreg_lock, flags);
449 ns = timecounter_read(&fep->tc);
450 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
451 mutex_unlock(&fep->ptp_clk_mutex);
452
453 *ts = ns_to_timespec64(ns);
454
455 return 0;
456 }
457
458 /**
459 * fec_ptp_settime
460 * @ptp: the ptp clock structure
461 * @ts: the timespec containing the new time for the cycle counter
462 *
463 * reset the timecounter to use a new base value instead of the kernel
464 * wall timer value.
465 */
fec_ptp_settime(struct ptp_clock_info * ptp,const struct timespec64 * ts)466 static int fec_ptp_settime(struct ptp_clock_info *ptp,
467 const struct timespec64 *ts)
468 {
469 struct fec_enet_private *fep =
470 container_of(ptp, struct fec_enet_private, ptp_caps);
471
472 u64 ns;
473 unsigned long flags;
474 u32 counter;
475
476 mutex_lock(&fep->ptp_clk_mutex);
477 /* Check the ptp clock */
478 if (!fep->ptp_clk_on) {
479 mutex_unlock(&fep->ptp_clk_mutex);
480 return -EINVAL;
481 }
482
483 ns = timespec64_to_ns(ts);
484 /* Get the timer value based on timestamp.
485 * Update the counter with the masked value.
486 */
487 counter = ns & fep->cc.mask;
488
489 spin_lock_irqsave(&fep->tmreg_lock, flags);
490 writel(counter, fep->hwp + FEC_ATIME);
491 timecounter_init(&fep->tc, &fep->cc, ns);
492 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
493 mutex_unlock(&fep->ptp_clk_mutex);
494 return 0;
495 }
496
fec_ptp_pps_disable(struct fec_enet_private * fep,uint channel)497 static int fec_ptp_pps_disable(struct fec_enet_private *fep, uint channel)
498 {
499 unsigned long flags;
500
501 spin_lock_irqsave(&fep->tmreg_lock, flags);
502 writel(0, fep->hwp + FEC_TCSR(channel));
503 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
504
505 return 0;
506 }
507
508 /**
509 * fec_ptp_enable
510 * @ptp: the ptp clock structure
511 * @rq: the requested feature to change
512 * @on: whether to enable or disable the feature
513 *
514 */
fec_ptp_enable(struct ptp_clock_info * ptp,struct ptp_clock_request * rq,int on)515 static int fec_ptp_enable(struct ptp_clock_info *ptp,
516 struct ptp_clock_request *rq, int on)
517 {
518 struct fec_enet_private *fep =
519 container_of(ptp, struct fec_enet_private, ptp_caps);
520 ktime_t timeout;
521 struct timespec64 start_time, period;
522 u64 curr_time, delta, period_ns;
523 unsigned long flags;
524 int ret = 0;
525
526 if (rq->type == PTP_CLK_REQ_PPS) {
527 fep->reload_period = PPS_OUPUT_RELOAD_PERIOD;
528
529 ret = fec_ptp_enable_pps(fep, on);
530
531 return ret;
532 } else if (rq->type == PTP_CLK_REQ_PEROUT) {
533 /* Reject requests with unsupported flags */
534 if (rq->perout.flags)
535 return -EOPNOTSUPP;
536
537 if (rq->perout.index != fep->pps_channel)
538 return -EOPNOTSUPP;
539
540 period.tv_sec = rq->perout.period.sec;
541 period.tv_nsec = rq->perout.period.nsec;
542 period_ns = timespec64_to_ns(&period);
543
544 /* FEC PTP timer only has 31 bits, so if the period exceed
545 * 4s is not supported.
546 */
547 if (period_ns > FEC_PTP_MAX_NSEC_PERIOD) {
548 dev_err(&fep->pdev->dev, "The period must equal to or less than 4s!\n");
549 return -EOPNOTSUPP;
550 }
551
552 fep->reload_period = div_u64(period_ns, 2);
553 if (on && fep->reload_period) {
554 /* Convert 1588 timestamp to ns*/
555 start_time.tv_sec = rq->perout.start.sec;
556 start_time.tv_nsec = rq->perout.start.nsec;
557 fep->perout_stime = timespec64_to_ns(&start_time);
558
559 mutex_lock(&fep->ptp_clk_mutex);
560 if (!fep->ptp_clk_on) {
561 dev_err(&fep->pdev->dev, "Error: PTP clock is closed!\n");
562 mutex_unlock(&fep->ptp_clk_mutex);
563 return -EOPNOTSUPP;
564 }
565 spin_lock_irqsave(&fep->tmreg_lock, flags);
566 /* Read current timestamp */
567 curr_time = timecounter_read(&fep->tc);
568 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
569 mutex_unlock(&fep->ptp_clk_mutex);
570
571 /* Calculate time difference */
572 delta = fep->perout_stime - curr_time;
573
574 if (fep->perout_stime <= curr_time) {
575 dev_err(&fep->pdev->dev, "Start time must larger than current time!\n");
576 return -EINVAL;
577 }
578
579 /* Because the timer counter of FEC only has 31-bits, correspondingly,
580 * the time comparison register FEC_TCCR also only low 31 bits can be
581 * set. If the start time of pps signal exceeds current time more than
582 * 0x80000000 ns, a software timer is used and the timer expires about
583 * 1 second before the start time to be able to set FEC_TCCR.
584 */
585 if (delta > FEC_PTP_MAX_NSEC_COUNTER) {
586 timeout = ns_to_ktime(delta - NSEC_PER_SEC);
587 hrtimer_start(&fep->perout_timer, timeout, HRTIMER_MODE_REL);
588 } else {
589 return fec_ptp_pps_perout(fep);
590 }
591 } else {
592 fec_ptp_pps_disable(fep, fep->pps_channel);
593 }
594
595 return 0;
596 } else {
597 return -EOPNOTSUPP;
598 }
599 }
600
fec_ptp_set(struct net_device * ndev,struct kernel_hwtstamp_config * config,struct netlink_ext_ack * extack)601 int fec_ptp_set(struct net_device *ndev, struct kernel_hwtstamp_config *config,
602 struct netlink_ext_ack *extack)
603 {
604 struct fec_enet_private *fep = netdev_priv(ndev);
605
606 switch (config->tx_type) {
607 case HWTSTAMP_TX_OFF:
608 fep->hwts_tx_en = 0;
609 break;
610 case HWTSTAMP_TX_ON:
611 fep->hwts_tx_en = 1;
612 break;
613 default:
614 return -ERANGE;
615 }
616
617 switch (config->rx_filter) {
618 case HWTSTAMP_FILTER_NONE:
619 fep->hwts_rx_en = 0;
620 break;
621
622 default:
623 fep->hwts_rx_en = 1;
624 config->rx_filter = HWTSTAMP_FILTER_ALL;
625 break;
626 }
627
628 return 0;
629 }
630
fec_ptp_get(struct net_device * ndev,struct kernel_hwtstamp_config * config)631 void fec_ptp_get(struct net_device *ndev, struct kernel_hwtstamp_config *config)
632 {
633 struct fec_enet_private *fep = netdev_priv(ndev);
634
635 config->flags = 0;
636 config->tx_type = fep->hwts_tx_en ? HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF;
637 config->rx_filter = (fep->hwts_rx_en ?
638 HWTSTAMP_FILTER_ALL : HWTSTAMP_FILTER_NONE);
639 }
640
641 /*
642 * fec_time_keep - call timecounter_read every second to avoid timer overrun
643 * because ENET just support 32bit counter, will timeout in 4s
644 */
fec_time_keep(struct work_struct * work)645 static void fec_time_keep(struct work_struct *work)
646 {
647 struct delayed_work *dwork = to_delayed_work(work);
648 struct fec_enet_private *fep = container_of(dwork, struct fec_enet_private, time_keep);
649 unsigned long flags;
650
651 mutex_lock(&fep->ptp_clk_mutex);
652 if (fep->ptp_clk_on) {
653 spin_lock_irqsave(&fep->tmreg_lock, flags);
654 timecounter_read(&fep->tc);
655 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
656 }
657 mutex_unlock(&fep->ptp_clk_mutex);
658
659 schedule_delayed_work(&fep->time_keep, HZ);
660 }
661
662 /* This function checks the pps event and reloads the timer compare counter. */
fec_pps_interrupt(int irq,void * dev_id)663 static irqreturn_t fec_pps_interrupt(int irq, void *dev_id)
664 {
665 struct net_device *ndev = dev_id;
666 struct fec_enet_private *fep = netdev_priv(ndev);
667 u32 val;
668 u8 channel = fep->pps_channel;
669 struct ptp_clock_event event;
670
671 val = readl(fep->hwp + FEC_TCSR(channel));
672 if (val & FEC_T_TF_MASK) {
673 /* Write the next next compare(not the next according the spec)
674 * value to the register
675 */
676 writel(fep->next_counter, fep->hwp + FEC_TCCR(channel));
677 do {
678 writel(val, fep->hwp + FEC_TCSR(channel));
679 } while (readl(fep->hwp + FEC_TCSR(channel)) & FEC_T_TF_MASK);
680
681 /* Update the counter; */
682 fep->next_counter = (fep->next_counter + fep->reload_period) &
683 fep->cc.mask;
684
685 event.type = PTP_CLOCK_PPS;
686 ptp_clock_event(fep->ptp_clock, &event);
687 return IRQ_HANDLED;
688 }
689
690 return IRQ_NONE;
691 }
692
693 /**
694 * fec_ptp_init
695 * @pdev: The FEC network adapter
696 * @irq_idx: the interrupt index
697 *
698 * This function performs the required steps for enabling ptp
699 * support. If ptp support has already been loaded it simply calls the
700 * cyclecounter init routine and exits.
701 */
702
fec_ptp_init(struct platform_device * pdev,int irq_idx)703 void fec_ptp_init(struct platform_device *pdev, int irq_idx)
704 {
705 struct net_device *ndev = platform_get_drvdata(pdev);
706 struct fec_enet_private *fep = netdev_priv(ndev);
707 struct device_node *np = fep->pdev->dev.of_node;
708 int irq;
709 int ret;
710
711 fep->ptp_caps.owner = THIS_MODULE;
712 strscpy(fep->ptp_caps.name, "fec ptp", sizeof(fep->ptp_caps.name));
713
714 fep->pps_channel = DEFAULT_PPS_CHANNEL;
715 of_property_read_u32(np, "fsl,pps-channel", &fep->pps_channel);
716
717 fep->ptp_caps.max_adj = 250000000;
718 fep->ptp_caps.n_alarm = 0;
719 fep->ptp_caps.n_ext_ts = 0;
720 fep->ptp_caps.n_per_out = 1;
721 fep->ptp_caps.n_pins = 0;
722 fep->ptp_caps.pps = 1;
723 fep->ptp_caps.adjfine = fec_ptp_adjfine;
724 fep->ptp_caps.adjtime = fec_ptp_adjtime;
725 fep->ptp_caps.gettime64 = fec_ptp_gettime;
726 fep->ptp_caps.settime64 = fec_ptp_settime;
727 fep->ptp_caps.enable = fec_ptp_enable;
728
729 fep->cycle_speed = clk_get_rate(fep->clk_ptp);
730 if (!fep->cycle_speed) {
731 fep->cycle_speed = NSEC_PER_SEC;
732 dev_err(&fep->pdev->dev, "clk_ptp clock rate is zero\n");
733 }
734 fep->ptp_inc = NSEC_PER_SEC / fep->cycle_speed;
735
736 spin_lock_init(&fep->tmreg_lock);
737
738 fec_ptp_start_cyclecounter(ndev);
739
740 INIT_DELAYED_WORK(&fep->time_keep, fec_time_keep);
741
742 hrtimer_init(&fep->perout_timer, CLOCK_REALTIME, HRTIMER_MODE_REL);
743 fep->perout_timer.function = fec_ptp_pps_perout_handler;
744
745 irq = platform_get_irq_byname_optional(pdev, "pps");
746 if (irq < 0)
747 irq = platform_get_irq_optional(pdev, irq_idx);
748 /* Failure to get an irq is not fatal,
749 * only the PTP_CLOCK_PPS clock events should stop
750 */
751 if (irq >= 0) {
752 ret = devm_request_irq(&pdev->dev, irq, fec_pps_interrupt,
753 0, pdev->name, ndev);
754 if (ret < 0)
755 dev_warn(&pdev->dev, "request for pps irq failed(%d)\n",
756 ret);
757 }
758
759 fep->ptp_clock = ptp_clock_register(&fep->ptp_caps, &pdev->dev);
760 if (IS_ERR(fep->ptp_clock)) {
761 fep->ptp_clock = NULL;
762 dev_err(&pdev->dev, "ptp_clock_register failed\n");
763 }
764
765 schedule_delayed_work(&fep->time_keep, HZ);
766 }
767
fec_ptp_save_state(struct fec_enet_private * fep)768 void fec_ptp_save_state(struct fec_enet_private *fep)
769 {
770 unsigned long flags;
771 u32 atime_inc_corr;
772
773 spin_lock_irqsave(&fep->tmreg_lock, flags);
774
775 fep->ptp_saved_state.pps_enable = fep->pps_enable;
776
777 fep->ptp_saved_state.ns_phc = timecounter_read(&fep->tc);
778 fep->ptp_saved_state.ns_sys = ktime_get_ns();
779
780 fep->ptp_saved_state.at_corr = readl(fep->hwp + FEC_ATIME_CORR);
781 atime_inc_corr = readl(fep->hwp + FEC_ATIME_INC) & FEC_T_INC_CORR_MASK;
782 fep->ptp_saved_state.at_inc_corr = (u8)(atime_inc_corr >> FEC_T_INC_CORR_OFFSET);
783
784 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
785 }
786
787 /* Restore PTP functionality after a reset */
fec_ptp_restore_state(struct fec_enet_private * fep)788 void fec_ptp_restore_state(struct fec_enet_private *fep)
789 {
790 u32 atime_inc = readl(fep->hwp + FEC_ATIME_INC) & FEC_T_INC_MASK;
791 unsigned long flags;
792 u32 counter;
793 u64 ns;
794
795 spin_lock_irqsave(&fep->tmreg_lock, flags);
796
797 /* Reset turned it off, so adjust our status flag */
798 fep->pps_enable = 0;
799
800 writel(fep->ptp_saved_state.at_corr, fep->hwp + FEC_ATIME_CORR);
801 atime_inc |= ((u32)fep->ptp_saved_state.at_inc_corr) << FEC_T_INC_CORR_OFFSET;
802 writel(atime_inc, fep->hwp + FEC_ATIME_INC);
803
804 ns = ktime_get_ns() - fep->ptp_saved_state.ns_sys + fep->ptp_saved_state.ns_phc;
805 counter = ns & fep->cc.mask;
806 writel(counter, fep->hwp + FEC_ATIME);
807 timecounter_init(&fep->tc, &fep->cc, ns);
808
809 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
810
811 /* Restart PPS if needed */
812 if (fep->ptp_saved_state.pps_enable) {
813 /* Re-enable PPS */
814 fec_ptp_enable_pps(fep, 1);
815 }
816 }
817
fec_ptp_stop(struct platform_device * pdev)818 void fec_ptp_stop(struct platform_device *pdev)
819 {
820 struct net_device *ndev = platform_get_drvdata(pdev);
821 struct fec_enet_private *fep = netdev_priv(ndev);
822
823 if (fep->pps_enable)
824 fec_ptp_enable_pps(fep, 0);
825
826 cancel_delayed_work_sync(&fep->time_keep);
827 hrtimer_cancel(&fep->perout_timer);
828 if (fep->ptp_clock)
829 ptp_clock_unregister(fep->ptp_clock);
830 }
831