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 FEC_CHANNLE_0 0
88 #define DEFAULT_PPS_CHANNEL FEC_CHANNLE_0
89
90 #define FEC_PTP_MAX_NSEC_PERIOD 4000000000ULL
91 #define FEC_PTP_MAX_NSEC_COUNTER 0x80000000ULL
92
93 /**
94 * fec_ptp_enable_pps
95 * @fep: the fec_enet_private structure handle
96 * @enable: enable the channel pps output
97 *
98 * This function enble the PPS ouput on the timer channel.
99 */
fec_ptp_enable_pps(struct fec_enet_private * fep,uint enable)100 static int fec_ptp_enable_pps(struct fec_enet_private *fep, uint enable)
101 {
102 unsigned long flags;
103 u32 val, tempval;
104 struct timespec64 ts;
105 u64 ns;
106
107 if (fep->pps_enable == enable)
108 return 0;
109
110 fep->pps_channel = DEFAULT_PPS_CHANNEL;
111 fep->reload_period = PPS_OUPUT_RELOAD_PERIOD;
112
113 spin_lock_irqsave(&fep->tmreg_lock, flags);
114
115 if (enable) {
116 /* clear capture or output compare interrupt status if have.
117 */
118 writel(FEC_T_TF_MASK, fep->hwp + FEC_TCSR(fep->pps_channel));
119
120 /* It is recommended to double check the TMODE field in the
121 * TCSR register to be cleared before the first compare counter
122 * is written into TCCR register. Just add a double check.
123 */
124 val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
125 do {
126 val &= ~(FEC_T_TMODE_MASK);
127 writel(val, fep->hwp + FEC_TCSR(fep->pps_channel));
128 val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
129 } while (val & FEC_T_TMODE_MASK);
130
131 /* Dummy read counter to update the counter */
132 timecounter_read(&fep->tc);
133 /* We want to find the first compare event in the next
134 * second point. So we need to know what the ptp time
135 * is now and how many nanoseconds is ahead to get next second.
136 * The remaining nanosecond ahead before the next second would be
137 * NSEC_PER_SEC - ts.tv_nsec. Add the remaining nanoseconds
138 * to current timer would be next second.
139 */
140 tempval = fep->cc.read(&fep->cc);
141 /* Convert the ptp local counter to 1588 timestamp */
142 ns = timecounter_cyc2time(&fep->tc, tempval);
143 ts = ns_to_timespec64(ns);
144
145 /* The tempval is less than 3 seconds, and so val is less than
146 * 4 seconds. No overflow for 32bit calculation.
147 */
148 val = NSEC_PER_SEC - (u32)ts.tv_nsec + tempval;
149
150 /* Need to consider the situation that the current time is
151 * very close to the second point, which means NSEC_PER_SEC
152 * - ts.tv_nsec is close to be zero(For example 20ns); Since the timer
153 * is still running when we calculate the first compare event, it is
154 * possible that the remaining nanoseonds run out before the compare
155 * counter is calculated and written into TCCR register. To avoid
156 * this possibility, we will set the compare event to be the next
157 * of next second. The current setting is 31-bit timer and wrap
158 * around over 2 seconds. So it is okay to set the next of next
159 * seond for the timer.
160 */
161 val += NSEC_PER_SEC;
162
163 /* We add (2 * NSEC_PER_SEC - (u32)ts.tv_nsec) to current
164 * ptp counter, which maybe cause 32-bit wrap. Since the
165 * (NSEC_PER_SEC - (u32)ts.tv_nsec) is less than 2 second.
166 * We can ensure the wrap will not cause issue. If the offset
167 * is bigger than fep->cc.mask would be a error.
168 */
169 val &= fep->cc.mask;
170 writel(val, fep->hwp + FEC_TCCR(fep->pps_channel));
171
172 /* Calculate the second the compare event timestamp */
173 fep->next_counter = (val + fep->reload_period) & fep->cc.mask;
174
175 /* * Enable compare event when overflow */
176 val = readl(fep->hwp + FEC_ATIME_CTRL);
177 val |= FEC_T_CTRL_PINPER;
178 writel(val, fep->hwp + FEC_ATIME_CTRL);
179
180 /* Compare channel setting. */
181 val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
182 val |= (1 << FEC_T_TF_OFFSET | 1 << FEC_T_TIE_OFFSET);
183 val &= ~(1 << FEC_T_TDRE_OFFSET);
184 val &= ~(FEC_T_TMODE_MASK);
185 val |= (FEC_HIGH_PULSE << FEC_T_TMODE_OFFSET);
186 writel(val, fep->hwp + FEC_TCSR(fep->pps_channel));
187
188 /* Write the second compare event timestamp and calculate
189 * the third timestamp. Refer the TCCR register detail in the spec.
190 */
191 writel(fep->next_counter, fep->hwp + FEC_TCCR(fep->pps_channel));
192 fep->next_counter = (fep->next_counter + fep->reload_period) & fep->cc.mask;
193 } else {
194 writel(0, fep->hwp + FEC_TCSR(fep->pps_channel));
195 }
196
197 fep->pps_enable = enable;
198 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
199
200 return 0;
201 }
202
fec_ptp_pps_perout(struct fec_enet_private * fep)203 static int fec_ptp_pps_perout(struct fec_enet_private *fep)
204 {
205 u32 compare_val, ptp_hc, temp_val;
206 u64 curr_time;
207 unsigned long flags;
208
209 spin_lock_irqsave(&fep->tmreg_lock, flags);
210
211 /* Update time counter */
212 timecounter_read(&fep->tc);
213
214 /* Get the current ptp hardware time counter */
215 temp_val = readl(fep->hwp + FEC_ATIME_CTRL);
216 temp_val |= FEC_T_CTRL_CAPTURE;
217 writel(temp_val, fep->hwp + FEC_ATIME_CTRL);
218 if (fep->quirks & FEC_QUIRK_BUG_CAPTURE)
219 udelay(1);
220
221 ptp_hc = readl(fep->hwp + FEC_ATIME);
222
223 /* Convert the ptp local counter to 1588 timestamp */
224 curr_time = timecounter_cyc2time(&fep->tc, ptp_hc);
225
226 /* If the pps start time less than current time add 100ms, just return.
227 * Because the software might not able to set the comparison time into
228 * the FEC_TCCR register in time and missed the start time.
229 */
230 if (fep->perout_stime < curr_time + 100 * NSEC_PER_MSEC) {
231 dev_err(&fep->pdev->dev, "Current time is too close to the start time!\n");
232 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
233 return -1;
234 }
235
236 compare_val = fep->perout_stime - curr_time + ptp_hc;
237 compare_val &= fep->cc.mask;
238
239 writel(compare_val, fep->hwp + FEC_TCCR(fep->pps_channel));
240 fep->next_counter = (compare_val + fep->reload_period) & fep->cc.mask;
241
242 /* Enable compare event when overflow */
243 temp_val = readl(fep->hwp + FEC_ATIME_CTRL);
244 temp_val |= FEC_T_CTRL_PINPER;
245 writel(temp_val, fep->hwp + FEC_ATIME_CTRL);
246
247 /* Compare channel setting. */
248 temp_val = readl(fep->hwp + FEC_TCSR(fep->pps_channel));
249 temp_val |= (1 << FEC_T_TF_OFFSET | 1 << FEC_T_TIE_OFFSET);
250 temp_val &= ~(1 << FEC_T_TDRE_OFFSET);
251 temp_val &= ~(FEC_T_TMODE_MASK);
252 temp_val |= (FEC_TMODE_TOGGLE << FEC_T_TMODE_OFFSET);
253 writel(temp_val, fep->hwp + FEC_TCSR(fep->pps_channel));
254
255 /* Write the second compare event timestamp and calculate
256 * the third timestamp. Refer the TCCR register detail in the spec.
257 */
258 writel(fep->next_counter, fep->hwp + FEC_TCCR(fep->pps_channel));
259 fep->next_counter = (fep->next_counter + fep->reload_period) & fep->cc.mask;
260 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
261
262 return 0;
263 }
264
fec_ptp_pps_perout_handler(struct hrtimer * timer)265 static enum hrtimer_restart fec_ptp_pps_perout_handler(struct hrtimer *timer)
266 {
267 struct fec_enet_private *fep = container_of(timer,
268 struct fec_enet_private, perout_timer);
269
270 fec_ptp_pps_perout(fep);
271
272 return HRTIMER_NORESTART;
273 }
274
275 /**
276 * fec_ptp_read - read raw cycle counter (to be used by time counter)
277 * @cc: the cyclecounter structure
278 *
279 * this function reads the cyclecounter registers and is called by the
280 * cyclecounter structure used to construct a ns counter from the
281 * arbitrary fixed point registers
282 */
fec_ptp_read(const struct cyclecounter * cc)283 static u64 fec_ptp_read(const struct cyclecounter *cc)
284 {
285 struct fec_enet_private *fep =
286 container_of(cc, struct fec_enet_private, cc);
287 u32 tempval;
288
289 tempval = readl(fep->hwp + FEC_ATIME_CTRL);
290 tempval |= FEC_T_CTRL_CAPTURE;
291 writel(tempval, fep->hwp + FEC_ATIME_CTRL);
292
293 if (fep->quirks & FEC_QUIRK_BUG_CAPTURE)
294 udelay(1);
295
296 return readl(fep->hwp + FEC_ATIME);
297 }
298
299 /**
300 * fec_ptp_start_cyclecounter - create the cycle counter from hw
301 * @ndev: network device
302 *
303 * this function initializes the timecounter and cyclecounter
304 * structures for use in generated a ns counter from the arbitrary
305 * fixed point cycles registers in the hardware.
306 */
fec_ptp_start_cyclecounter(struct net_device * ndev)307 void fec_ptp_start_cyclecounter(struct net_device *ndev)
308 {
309 struct fec_enet_private *fep = netdev_priv(ndev);
310 unsigned long flags;
311 int inc;
312
313 inc = 1000000000 / fep->cycle_speed;
314
315 /* grab the ptp lock */
316 spin_lock_irqsave(&fep->tmreg_lock, flags);
317
318 /* 1ns counter */
319 writel(inc << FEC_T_INC_OFFSET, fep->hwp + FEC_ATIME_INC);
320
321 /* use 31-bit timer counter */
322 writel(FEC_COUNTER_PERIOD, fep->hwp + FEC_ATIME_EVT_PERIOD);
323
324 writel(FEC_T_CTRL_ENABLE | FEC_T_CTRL_PERIOD_RST,
325 fep->hwp + FEC_ATIME_CTRL);
326
327 memset(&fep->cc, 0, sizeof(fep->cc));
328 fep->cc.read = fec_ptp_read;
329 fep->cc.mask = CLOCKSOURCE_MASK(31);
330 fep->cc.shift = 31;
331 fep->cc.mult = FEC_CC_MULT;
332
333 /* reset the ns time counter */
334 timecounter_init(&fep->tc, &fep->cc, 0);
335
336 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
337 }
338
339 /**
340 * fec_ptp_adjfine - adjust ptp cycle frequency
341 * @ptp: the ptp clock structure
342 * @scaled_ppm: scaled parts per million adjustment from base
343 *
344 * Adjust the frequency of the ptp cycle counter by the
345 * indicated amount from the base frequency.
346 *
347 * Scaled parts per million is ppm with a 16-bit binary fractional field.
348 *
349 * Because ENET hardware frequency adjust is complex,
350 * using software method to do that.
351 */
fec_ptp_adjfine(struct ptp_clock_info * ptp,long scaled_ppm)352 static int fec_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
353 {
354 s32 ppb = scaled_ppm_to_ppb(scaled_ppm);
355 unsigned long flags;
356 int neg_adj = 0;
357 u32 i, tmp;
358 u32 corr_inc, corr_period;
359 u32 corr_ns;
360 u64 lhs, rhs;
361
362 struct fec_enet_private *fep =
363 container_of(ptp, struct fec_enet_private, ptp_caps);
364
365 if (ppb == 0)
366 return 0;
367
368 if (ppb < 0) {
369 ppb = -ppb;
370 neg_adj = 1;
371 }
372
373 /* In theory, corr_inc/corr_period = ppb/NSEC_PER_SEC;
374 * Try to find the corr_inc between 1 to fep->ptp_inc to
375 * meet adjustment requirement.
376 */
377 lhs = NSEC_PER_SEC;
378 rhs = (u64)ppb * (u64)fep->ptp_inc;
379 for (i = 1; i <= fep->ptp_inc; i++) {
380 if (lhs >= rhs) {
381 corr_inc = i;
382 corr_period = div_u64(lhs, rhs);
383 break;
384 }
385 lhs += NSEC_PER_SEC;
386 }
387 /* Not found? Set it to high value - double speed
388 * correct in every clock step.
389 */
390 if (i > fep->ptp_inc) {
391 corr_inc = fep->ptp_inc;
392 corr_period = 1;
393 }
394
395 if (neg_adj)
396 corr_ns = fep->ptp_inc - corr_inc;
397 else
398 corr_ns = fep->ptp_inc + corr_inc;
399
400 spin_lock_irqsave(&fep->tmreg_lock, flags);
401
402 tmp = readl(fep->hwp + FEC_ATIME_INC) & FEC_T_INC_MASK;
403 tmp |= corr_ns << FEC_T_INC_CORR_OFFSET;
404 writel(tmp, fep->hwp + FEC_ATIME_INC);
405 corr_period = corr_period > 1 ? corr_period - 1 : corr_period;
406 writel(corr_period, fep->hwp + FEC_ATIME_CORR);
407 /* dummy read to update the timer. */
408 timecounter_read(&fep->tc);
409
410 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
411
412 return 0;
413 }
414
415 /**
416 * fec_ptp_adjtime
417 * @ptp: the ptp clock structure
418 * @delta: offset to adjust the cycle counter by
419 *
420 * adjust the timer by resetting the timecounter structure.
421 */
fec_ptp_adjtime(struct ptp_clock_info * ptp,s64 delta)422 static int fec_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
423 {
424 struct fec_enet_private *fep =
425 container_of(ptp, struct fec_enet_private, ptp_caps);
426 unsigned long flags;
427
428 spin_lock_irqsave(&fep->tmreg_lock, flags);
429 timecounter_adjtime(&fep->tc, delta);
430 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
431
432 return 0;
433 }
434
435 /**
436 * fec_ptp_gettime
437 * @ptp: the ptp clock structure
438 * @ts: timespec structure to hold the current time value
439 *
440 * read the timecounter and return the correct value on ns,
441 * after converting it into a struct timespec.
442 */
fec_ptp_gettime(struct ptp_clock_info * ptp,struct timespec64 * ts)443 static int fec_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
444 {
445 struct fec_enet_private *fep =
446 container_of(ptp, struct fec_enet_private, ptp_caps);
447 u64 ns;
448 unsigned long flags;
449
450 mutex_lock(&fep->ptp_clk_mutex);
451 /* Check the ptp clock */
452 if (!fep->ptp_clk_on) {
453 mutex_unlock(&fep->ptp_clk_mutex);
454 return -EINVAL;
455 }
456 spin_lock_irqsave(&fep->tmreg_lock, flags);
457 ns = timecounter_read(&fep->tc);
458 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
459 mutex_unlock(&fep->ptp_clk_mutex);
460
461 *ts = ns_to_timespec64(ns);
462
463 return 0;
464 }
465
466 /**
467 * fec_ptp_settime
468 * @ptp: the ptp clock structure
469 * @ts: the timespec containing the new time for the cycle counter
470 *
471 * reset the timecounter to use a new base value instead of the kernel
472 * wall timer value.
473 */
fec_ptp_settime(struct ptp_clock_info * ptp,const struct timespec64 * ts)474 static int fec_ptp_settime(struct ptp_clock_info *ptp,
475 const struct timespec64 *ts)
476 {
477 struct fec_enet_private *fep =
478 container_of(ptp, struct fec_enet_private, ptp_caps);
479
480 u64 ns;
481 unsigned long flags;
482 u32 counter;
483
484 mutex_lock(&fep->ptp_clk_mutex);
485 /* Check the ptp clock */
486 if (!fep->ptp_clk_on) {
487 mutex_unlock(&fep->ptp_clk_mutex);
488 return -EINVAL;
489 }
490
491 ns = timespec64_to_ns(ts);
492 /* Get the timer value based on timestamp.
493 * Update the counter with the masked value.
494 */
495 counter = ns & fep->cc.mask;
496
497 spin_lock_irqsave(&fep->tmreg_lock, flags);
498 writel(counter, fep->hwp + FEC_ATIME);
499 timecounter_init(&fep->tc, &fep->cc, ns);
500 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
501 mutex_unlock(&fep->ptp_clk_mutex);
502 return 0;
503 }
504
fec_ptp_pps_disable(struct fec_enet_private * fep,uint channel)505 static int fec_ptp_pps_disable(struct fec_enet_private *fep, uint channel)
506 {
507 unsigned long flags;
508
509 spin_lock_irqsave(&fep->tmreg_lock, flags);
510 writel(0, fep->hwp + FEC_TCSR(channel));
511 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
512
513 return 0;
514 }
515
516 /**
517 * fec_ptp_enable
518 * @ptp: the ptp clock structure
519 * @rq: the requested feature to change
520 * @on: whether to enable or disable the feature
521 *
522 */
fec_ptp_enable(struct ptp_clock_info * ptp,struct ptp_clock_request * rq,int on)523 static int fec_ptp_enable(struct ptp_clock_info *ptp,
524 struct ptp_clock_request *rq, int on)
525 {
526 struct fec_enet_private *fep =
527 container_of(ptp, struct fec_enet_private, ptp_caps);
528 ktime_t timeout;
529 struct timespec64 start_time, period;
530 u64 curr_time, delta, period_ns;
531 unsigned long flags;
532 int ret = 0;
533
534 if (rq->type == PTP_CLK_REQ_PPS) {
535 ret = fec_ptp_enable_pps(fep, on);
536
537 return ret;
538 } else if (rq->type == PTP_CLK_REQ_PEROUT) {
539 /* Reject requests with unsupported flags */
540 if (rq->perout.flags)
541 return -EOPNOTSUPP;
542
543 if (rq->perout.index != DEFAULT_PPS_CHANNEL)
544 return -EOPNOTSUPP;
545
546 fep->pps_channel = DEFAULT_PPS_CHANNEL;
547 period.tv_sec = rq->perout.period.sec;
548 period.tv_nsec = rq->perout.period.nsec;
549 period_ns = timespec64_to_ns(&period);
550
551 /* FEC PTP timer only has 31 bits, so if the period exceed
552 * 4s is not supported.
553 */
554 if (period_ns > FEC_PTP_MAX_NSEC_PERIOD) {
555 dev_err(&fep->pdev->dev, "The period must equal to or less than 4s!\n");
556 return -EOPNOTSUPP;
557 }
558
559 fep->reload_period = div_u64(period_ns, 2);
560 if (on && fep->reload_period) {
561 /* Convert 1588 timestamp to ns*/
562 start_time.tv_sec = rq->perout.start.sec;
563 start_time.tv_nsec = rq->perout.start.nsec;
564 fep->perout_stime = timespec64_to_ns(&start_time);
565
566 mutex_lock(&fep->ptp_clk_mutex);
567 if (!fep->ptp_clk_on) {
568 dev_err(&fep->pdev->dev, "Error: PTP clock is closed!\n");
569 mutex_unlock(&fep->ptp_clk_mutex);
570 return -EOPNOTSUPP;
571 }
572 spin_lock_irqsave(&fep->tmreg_lock, flags);
573 /* Read current timestamp */
574 curr_time = timecounter_read(&fep->tc);
575 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
576 mutex_unlock(&fep->ptp_clk_mutex);
577
578 /* Calculate time difference */
579 delta = fep->perout_stime - curr_time;
580
581 if (fep->perout_stime <= curr_time) {
582 dev_err(&fep->pdev->dev, "Start time must larger than current time!\n");
583 return -EINVAL;
584 }
585
586 /* Because the timer counter of FEC only has 31-bits, correspondingly,
587 * the time comparison register FEC_TCCR also only low 31 bits can be
588 * set. If the start time of pps signal exceeds current time more than
589 * 0x80000000 ns, a software timer is used and the timer expires about
590 * 1 second before the start time to be able to set FEC_TCCR.
591 */
592 if (delta > FEC_PTP_MAX_NSEC_COUNTER) {
593 timeout = ns_to_ktime(delta - NSEC_PER_SEC);
594 hrtimer_start(&fep->perout_timer, timeout, HRTIMER_MODE_REL);
595 } else {
596 return fec_ptp_pps_perout(fep);
597 }
598 } else {
599 fec_ptp_pps_disable(fep, fep->pps_channel);
600 }
601
602 return 0;
603 } else {
604 return -EOPNOTSUPP;
605 }
606 }
607
fec_ptp_set(struct net_device * ndev,struct kernel_hwtstamp_config * config,struct netlink_ext_ack * extack)608 int fec_ptp_set(struct net_device *ndev, struct kernel_hwtstamp_config *config,
609 struct netlink_ext_ack *extack)
610 {
611 struct fec_enet_private *fep = netdev_priv(ndev);
612
613 switch (config->tx_type) {
614 case HWTSTAMP_TX_OFF:
615 fep->hwts_tx_en = 0;
616 break;
617 case HWTSTAMP_TX_ON:
618 fep->hwts_tx_en = 1;
619 break;
620 default:
621 return -ERANGE;
622 }
623
624 switch (config->rx_filter) {
625 case HWTSTAMP_FILTER_NONE:
626 fep->hwts_rx_en = 0;
627 break;
628
629 default:
630 fep->hwts_rx_en = 1;
631 config->rx_filter = HWTSTAMP_FILTER_ALL;
632 break;
633 }
634
635 return 0;
636 }
637
fec_ptp_get(struct net_device * ndev,struct kernel_hwtstamp_config * config)638 void fec_ptp_get(struct net_device *ndev, struct kernel_hwtstamp_config *config)
639 {
640 struct fec_enet_private *fep = netdev_priv(ndev);
641
642 config->flags = 0;
643 config->tx_type = fep->hwts_tx_en ? HWTSTAMP_TX_ON : HWTSTAMP_TX_OFF;
644 config->rx_filter = (fep->hwts_rx_en ?
645 HWTSTAMP_FILTER_ALL : HWTSTAMP_FILTER_NONE);
646 }
647
648 /*
649 * fec_time_keep - call timecounter_read every second to avoid timer overrun
650 * because ENET just support 32bit counter, will timeout in 4s
651 */
fec_time_keep(struct work_struct * work)652 static void fec_time_keep(struct work_struct *work)
653 {
654 struct delayed_work *dwork = to_delayed_work(work);
655 struct fec_enet_private *fep = container_of(dwork, struct fec_enet_private, time_keep);
656 unsigned long flags;
657
658 mutex_lock(&fep->ptp_clk_mutex);
659 if (fep->ptp_clk_on) {
660 spin_lock_irqsave(&fep->tmreg_lock, flags);
661 timecounter_read(&fep->tc);
662 spin_unlock_irqrestore(&fep->tmreg_lock, flags);
663 }
664 mutex_unlock(&fep->ptp_clk_mutex);
665
666 schedule_delayed_work(&fep->time_keep, HZ);
667 }
668
669 /* This function checks the pps event and reloads the timer compare counter. */
fec_pps_interrupt(int irq,void * dev_id)670 static irqreturn_t fec_pps_interrupt(int irq, void *dev_id)
671 {
672 struct net_device *ndev = dev_id;
673 struct fec_enet_private *fep = netdev_priv(ndev);
674 u32 val;
675 u8 channel = fep->pps_channel;
676 struct ptp_clock_event event;
677
678 val = readl(fep->hwp + FEC_TCSR(channel));
679 if (val & FEC_T_TF_MASK) {
680 /* Write the next next compare(not the next according the spec)
681 * value to the register
682 */
683 writel(fep->next_counter, fep->hwp + FEC_TCCR(channel));
684 do {
685 writel(val, fep->hwp + FEC_TCSR(channel));
686 } while (readl(fep->hwp + FEC_TCSR(channel)) & FEC_T_TF_MASK);
687
688 /* Update the counter; */
689 fep->next_counter = (fep->next_counter + fep->reload_period) &
690 fep->cc.mask;
691
692 event.type = PTP_CLOCK_PPS;
693 ptp_clock_event(fep->ptp_clock, &event);
694 return IRQ_HANDLED;
695 }
696
697 return IRQ_NONE;
698 }
699
700 /**
701 * fec_ptp_init
702 * @pdev: The FEC network adapter
703 * @irq_idx: the interrupt index
704 *
705 * This function performs the required steps for enabling ptp
706 * support. If ptp support has already been loaded it simply calls the
707 * cyclecounter init routine and exits.
708 */
709
fec_ptp_init(struct platform_device * pdev,int irq_idx)710 void fec_ptp_init(struct platform_device *pdev, int irq_idx)
711 {
712 struct net_device *ndev = platform_get_drvdata(pdev);
713 struct fec_enet_private *fep = netdev_priv(ndev);
714 int irq;
715 int ret;
716
717 fep->ptp_caps.owner = THIS_MODULE;
718 strscpy(fep->ptp_caps.name, "fec ptp", sizeof(fep->ptp_caps.name));
719
720 fep->ptp_caps.max_adj = 250000000;
721 fep->ptp_caps.n_alarm = 0;
722 fep->ptp_caps.n_ext_ts = 0;
723 fep->ptp_caps.n_per_out = 1;
724 fep->ptp_caps.n_pins = 0;
725 fep->ptp_caps.pps = 1;
726 fep->ptp_caps.adjfine = fec_ptp_adjfine;
727 fep->ptp_caps.adjtime = fec_ptp_adjtime;
728 fep->ptp_caps.gettime64 = fec_ptp_gettime;
729 fep->ptp_caps.settime64 = fec_ptp_settime;
730 fep->ptp_caps.enable = fec_ptp_enable;
731
732 fep->cycle_speed = clk_get_rate(fep->clk_ptp);
733 if (!fep->cycle_speed) {
734 fep->cycle_speed = NSEC_PER_SEC;
735 dev_err(&fep->pdev->dev, "clk_ptp clock rate is zero\n");
736 }
737 fep->ptp_inc = NSEC_PER_SEC / fep->cycle_speed;
738
739 spin_lock_init(&fep->tmreg_lock);
740
741 fec_ptp_start_cyclecounter(ndev);
742
743 INIT_DELAYED_WORK(&fep->time_keep, fec_time_keep);
744
745 hrtimer_init(&fep->perout_timer, CLOCK_REALTIME, HRTIMER_MODE_REL);
746 fep->perout_timer.function = fec_ptp_pps_perout_handler;
747
748 irq = platform_get_irq_byname_optional(pdev, "pps");
749 if (irq < 0)
750 irq = platform_get_irq_optional(pdev, irq_idx);
751 /* Failure to get an irq is not fatal,
752 * only the PTP_CLOCK_PPS clock events should stop
753 */
754 if (irq >= 0) {
755 ret = devm_request_irq(&pdev->dev, irq, fec_pps_interrupt,
756 0, pdev->name, ndev);
757 if (ret < 0)
758 dev_warn(&pdev->dev, "request for pps irq failed(%d)\n",
759 ret);
760 }
761
762 fep->ptp_clock = ptp_clock_register(&fep->ptp_caps, &pdev->dev);
763 if (IS_ERR(fep->ptp_clock)) {
764 fep->ptp_clock = NULL;
765 dev_err(&pdev->dev, "ptp_clock_register failed\n");
766 }
767
768 schedule_delayed_work(&fep->time_keep, HZ);
769 }
770
fec_ptp_stop(struct platform_device * pdev)771 void fec_ptp_stop(struct platform_device *pdev)
772 {
773 struct net_device *ndev = platform_get_drvdata(pdev);
774 struct fec_enet_private *fep = netdev_priv(ndev);
775
776 cancel_delayed_work_sync(&fep->time_keep);
777 hrtimer_cancel(&fep->perout_timer);
778 if (fep->ptp_clock)
779 ptp_clock_unregister(fep->ptp_clock);
780 }
781
