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v6.8
  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 */
100static 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
203static 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
265static 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 */
283static 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 */
307void 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 */
352static 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 */
422static 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 */
443static 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 */
474static 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
505static 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 */
523static 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
608int 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
638void 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 */
652static 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. */
670static 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
710void 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
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
771void 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}
v6.13.7
  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 */
100static 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 */
123static 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
225static 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
281static 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 */
299void 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 */
344static 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 */
414static 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 */
435static 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 */
466static 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
497static 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 */
515static 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
601int 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
631void 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 */
645static 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. */
663static 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
703void 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
768void 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 */
788void 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
818void 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}