1 /*
2 * PTP 1588 clock using the eTSEC
3 *
4 * Copyright (C) 2010 OMICRON electronics GmbH
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 */
20
21 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22
23 #include <linux/device.h>
24 #include <linux/hrtimer.h>
25 #include <linux/interrupt.h>
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/of.h>
29 #include <linux/of_platform.h>
30 #include <linux/timex.h>
31 #include <linux/io.h>
32
33 #include <linux/ptp_clock_kernel.h>
34
35 #include "gianfar.h"
36
37 /*
38 * gianfar ptp registers
39 * Generated by regen.tcl on Thu May 13 01:38:57 PM CEST 2010
40 */
41 struct gianfar_ptp_registers {
42 u32 tmr_ctrl; /* Timer control register */
43 u32 tmr_tevent; /* Timestamp event register */
44 u32 tmr_temask; /* Timer event mask register */
45 u32 tmr_pevent; /* Timestamp event register */
46 u32 tmr_pemask; /* Timer event mask register */
47 u32 tmr_stat; /* Timestamp status register */
48 u32 tmr_cnt_h; /* Timer counter high register */
49 u32 tmr_cnt_l; /* Timer counter low register */
50 u32 tmr_add; /* Timer drift compensation addend register */
51 u32 tmr_acc; /* Timer accumulator register */
52 u32 tmr_prsc; /* Timer prescale */
53 u8 res1[4];
54 u32 tmroff_h; /* Timer offset high */
55 u32 tmroff_l; /* Timer offset low */
56 u8 res2[8];
57 u32 tmr_alarm1_h; /* Timer alarm 1 high register */
58 u32 tmr_alarm1_l; /* Timer alarm 1 high register */
59 u32 tmr_alarm2_h; /* Timer alarm 2 high register */
60 u32 tmr_alarm2_l; /* Timer alarm 2 high register */
61 u8 res3[48];
62 u32 tmr_fiper1; /* Timer fixed period interval */
63 u32 tmr_fiper2; /* Timer fixed period interval */
64 u32 tmr_fiper3; /* Timer fixed period interval */
65 u8 res4[20];
66 u32 tmr_etts1_h; /* Timestamp of general purpose external trigger */
67 u32 tmr_etts1_l; /* Timestamp of general purpose external trigger */
68 u32 tmr_etts2_h; /* Timestamp of general purpose external trigger */
69 u32 tmr_etts2_l; /* Timestamp of general purpose external trigger */
70 };
71
72 /* Bit definitions for the TMR_CTRL register */
73 #define ALM1P (1<<31) /* Alarm1 output polarity */
74 #define ALM2P (1<<30) /* Alarm2 output polarity */
75 #define FIPERST (1<<28) /* FIPER start indication */
76 #define PP1L (1<<27) /* Fiper1 pulse loopback mode enabled. */
77 #define PP2L (1<<26) /* Fiper2 pulse loopback mode enabled. */
78 #define TCLK_PERIOD_SHIFT (16) /* 1588 timer reference clock period. */
79 #define TCLK_PERIOD_MASK (0x3ff)
80 #define RTPE (1<<15) /* Record Tx Timestamp to PAL Enable. */
81 #define FRD (1<<14) /* FIPER Realignment Disable */
82 #define ESFDP (1<<11) /* External Tx/Rx SFD Polarity. */
83 #define ESFDE (1<<10) /* External Tx/Rx SFD Enable. */
84 #define ETEP2 (1<<9) /* External trigger 2 edge polarity */
85 #define ETEP1 (1<<8) /* External trigger 1 edge polarity */
86 #define COPH (1<<7) /* Generated clock output phase. */
87 #define CIPH (1<<6) /* External oscillator input clock phase */
88 #define TMSR (1<<5) /* Timer soft reset. */
89 #define BYP (1<<3) /* Bypass drift compensated clock */
90 #define TE (1<<2) /* 1588 timer enable. */
91 #define CKSEL_SHIFT (0) /* 1588 Timer reference clock source */
92 #define CKSEL_MASK (0x3)
93
94 /* Bit definitions for the TMR_TEVENT register */
95 #define ETS2 (1<<25) /* External trigger 2 timestamp sampled */
96 #define ETS1 (1<<24) /* External trigger 1 timestamp sampled */
97 #define ALM2 (1<<17) /* Current time = alarm time register 2 */
98 #define ALM1 (1<<16) /* Current time = alarm time register 1 */
99 #define PP1 (1<<7) /* periodic pulse generated on FIPER1 */
100 #define PP2 (1<<6) /* periodic pulse generated on FIPER2 */
101 #define PP3 (1<<5) /* periodic pulse generated on FIPER3 */
102
103 /* Bit definitions for the TMR_TEMASK register */
104 #define ETS2EN (1<<25) /* External trigger 2 timestamp enable */
105 #define ETS1EN (1<<24) /* External trigger 1 timestamp enable */
106 #define ALM2EN (1<<17) /* Timer ALM2 event enable */
107 #define ALM1EN (1<<16) /* Timer ALM1 event enable */
108 #define PP1EN (1<<7) /* Periodic pulse event 1 enable */
109 #define PP2EN (1<<6) /* Periodic pulse event 2 enable */
110
111 /* Bit definitions for the TMR_PEVENT register */
112 #define TXP2 (1<<9) /* PTP transmitted timestamp im TXTS2 */
113 #define TXP1 (1<<8) /* PTP transmitted timestamp in TXTS1 */
114 #define RXP (1<<0) /* PTP frame has been received */
115
116 /* Bit definitions for the TMR_PEMASK register */
117 #define TXP2EN (1<<9) /* Transmit PTP packet event 2 enable */
118 #define TXP1EN (1<<8) /* Transmit PTP packet event 1 enable */
119 #define RXPEN (1<<0) /* Receive PTP packet event enable */
120
121 /* Bit definitions for the TMR_STAT register */
122 #define STAT_VEC_SHIFT (0) /* Timer general purpose status vector */
123 #define STAT_VEC_MASK (0x3f)
124
125 /* Bit definitions for the TMR_PRSC register */
126 #define PRSC_OCK_SHIFT (0) /* Output clock division/prescale factor. */
127 #define PRSC_OCK_MASK (0xffff)
128
129
130 #define DRIVER "gianfar_ptp"
131 #define DEFAULT_CKSEL 1
132 #define N_EXT_TS 2
133 #define REG_SIZE sizeof(struct gianfar_ptp_registers)
134
135 struct etsects {
136 struct gianfar_ptp_registers __iomem *regs;
137 spinlock_t lock; /* protects regs */
138 struct ptp_clock *clock;
139 struct ptp_clock_info caps;
140 struct resource *rsrc;
141 int irq;
142 u64 alarm_interval; /* for periodic alarm */
143 u64 alarm_value;
144 u32 tclk_period; /* nanoseconds */
145 u32 tmr_prsc;
146 u32 tmr_add;
147 u32 cksel;
148 u32 tmr_fiper1;
149 u32 tmr_fiper2;
150 };
151
152 /*
153 * Register access functions
154 */
155
156 /* Caller must hold etsects->lock. */
tmr_cnt_read(struct etsects * etsects)157 static u64 tmr_cnt_read(struct etsects *etsects)
158 {
159 u64 ns;
160 u32 lo, hi;
161
162 lo = gfar_read(&etsects->regs->tmr_cnt_l);
163 hi = gfar_read(&etsects->regs->tmr_cnt_h);
164 ns = ((u64) hi) << 32;
165 ns |= lo;
166 return ns;
167 }
168
169 /* Caller must hold etsects->lock. */
tmr_cnt_write(struct etsects * etsects,u64 ns)170 static void tmr_cnt_write(struct etsects *etsects, u64 ns)
171 {
172 u32 hi = ns >> 32;
173 u32 lo = ns & 0xffffffff;
174
175 gfar_write(&etsects->regs->tmr_cnt_l, lo);
176 gfar_write(&etsects->regs->tmr_cnt_h, hi);
177 }
178
179 /* Caller must hold etsects->lock. */
set_alarm(struct etsects * etsects)180 static void set_alarm(struct etsects *etsects)
181 {
182 u64 ns;
183 u32 lo, hi;
184
185 ns = tmr_cnt_read(etsects) + 1500000000ULL;
186 ns = div_u64(ns, 1000000000UL) * 1000000000ULL;
187 ns -= etsects->tclk_period;
188 hi = ns >> 32;
189 lo = ns & 0xffffffff;
190 gfar_write(&etsects->regs->tmr_alarm1_l, lo);
191 gfar_write(&etsects->regs->tmr_alarm1_h, hi);
192 }
193
194 /* Caller must hold etsects->lock. */
set_fipers(struct etsects * etsects)195 static void set_fipers(struct etsects *etsects)
196 {
197 set_alarm(etsects);
198 gfar_write(&etsects->regs->tmr_fiper1, etsects->tmr_fiper1);
199 gfar_write(&etsects->regs->tmr_fiper2, etsects->tmr_fiper2);
200 }
201
202 /*
203 * Interrupt service routine
204 */
205
isr(int irq,void * priv)206 static irqreturn_t isr(int irq, void *priv)
207 {
208 struct etsects *etsects = priv;
209 struct ptp_clock_event event;
210 u64 ns;
211 u32 ack = 0, lo, hi, mask, val;
212
213 val = gfar_read(&etsects->regs->tmr_tevent);
214
215 if (val & ETS1) {
216 ack |= ETS1;
217 hi = gfar_read(&etsects->regs->tmr_etts1_h);
218 lo = gfar_read(&etsects->regs->tmr_etts1_l);
219 event.type = PTP_CLOCK_EXTTS;
220 event.index = 0;
221 event.timestamp = ((u64) hi) << 32;
222 event.timestamp |= lo;
223 ptp_clock_event(etsects->clock, &event);
224 }
225
226 if (val & ETS2) {
227 ack |= ETS2;
228 hi = gfar_read(&etsects->regs->tmr_etts2_h);
229 lo = gfar_read(&etsects->regs->tmr_etts2_l);
230 event.type = PTP_CLOCK_EXTTS;
231 event.index = 1;
232 event.timestamp = ((u64) hi) << 32;
233 event.timestamp |= lo;
234 ptp_clock_event(etsects->clock, &event);
235 }
236
237 if (val & ALM2) {
238 ack |= ALM2;
239 if (etsects->alarm_value) {
240 event.type = PTP_CLOCK_ALARM;
241 event.index = 0;
242 event.timestamp = etsects->alarm_value;
243 ptp_clock_event(etsects->clock, &event);
244 }
245 if (etsects->alarm_interval) {
246 ns = etsects->alarm_value + etsects->alarm_interval;
247 hi = ns >> 32;
248 lo = ns & 0xffffffff;
249 spin_lock(&etsects->lock);
250 gfar_write(&etsects->regs->tmr_alarm2_l, lo);
251 gfar_write(&etsects->regs->tmr_alarm2_h, hi);
252 spin_unlock(&etsects->lock);
253 etsects->alarm_value = ns;
254 } else {
255 gfar_write(&etsects->regs->tmr_tevent, ALM2);
256 spin_lock(&etsects->lock);
257 mask = gfar_read(&etsects->regs->tmr_temask);
258 mask &= ~ALM2EN;
259 gfar_write(&etsects->regs->tmr_temask, mask);
260 spin_unlock(&etsects->lock);
261 etsects->alarm_value = 0;
262 etsects->alarm_interval = 0;
263 }
264 }
265
266 if (val & PP1) {
267 ack |= PP1;
268 event.type = PTP_CLOCK_PPS;
269 ptp_clock_event(etsects->clock, &event);
270 }
271
272 if (ack) {
273 gfar_write(&etsects->regs->tmr_tevent, ack);
274 return IRQ_HANDLED;
275 } else
276 return IRQ_NONE;
277 }
278
279 /*
280 * PTP clock operations
281 */
282
ptp_gianfar_adjfine(struct ptp_clock_info * ptp,long scaled_ppm)283 static int ptp_gianfar_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
284 {
285 u64 adj, diff;
286 u32 tmr_add;
287 int neg_adj = 0;
288 struct etsects *etsects = container_of(ptp, struct etsects, caps);
289
290 if (scaled_ppm < 0) {
291 neg_adj = 1;
292 scaled_ppm = -scaled_ppm;
293 }
294 tmr_add = etsects->tmr_add;
295 adj = tmr_add;
296
297 /* calculate diff as adj*(scaled_ppm/65536)/1000000
298 * and round() to the nearest integer
299 */
300 adj *= scaled_ppm;
301 diff = div_u64(adj, 8000000);
302 diff = (diff >> 13) + ((diff >> 12) & 1);
303
304 tmr_add = neg_adj ? tmr_add - diff : tmr_add + diff;
305
306 gfar_write(&etsects->regs->tmr_add, tmr_add);
307
308 return 0;
309 }
310
ptp_gianfar_adjtime(struct ptp_clock_info * ptp,s64 delta)311 static int ptp_gianfar_adjtime(struct ptp_clock_info *ptp, s64 delta)
312 {
313 s64 now;
314 unsigned long flags;
315 struct etsects *etsects = container_of(ptp, struct etsects, caps);
316
317 spin_lock_irqsave(&etsects->lock, flags);
318
319 now = tmr_cnt_read(etsects);
320 now += delta;
321 tmr_cnt_write(etsects, now);
322 set_fipers(etsects);
323
324 spin_unlock_irqrestore(&etsects->lock, flags);
325
326 return 0;
327 }
328
ptp_gianfar_gettime(struct ptp_clock_info * ptp,struct timespec64 * ts)329 static int ptp_gianfar_gettime(struct ptp_clock_info *ptp,
330 struct timespec64 *ts)
331 {
332 u64 ns;
333 unsigned long flags;
334 struct etsects *etsects = container_of(ptp, struct etsects, caps);
335
336 spin_lock_irqsave(&etsects->lock, flags);
337
338 ns = tmr_cnt_read(etsects);
339
340 spin_unlock_irqrestore(&etsects->lock, flags);
341
342 *ts = ns_to_timespec64(ns);
343
344 return 0;
345 }
346
ptp_gianfar_settime(struct ptp_clock_info * ptp,const struct timespec64 * ts)347 static int ptp_gianfar_settime(struct ptp_clock_info *ptp,
348 const struct timespec64 *ts)
349 {
350 u64 ns;
351 unsigned long flags;
352 struct etsects *etsects = container_of(ptp, struct etsects, caps);
353
354 ns = timespec64_to_ns(ts);
355
356 spin_lock_irqsave(&etsects->lock, flags);
357
358 tmr_cnt_write(etsects, ns);
359 set_fipers(etsects);
360
361 spin_unlock_irqrestore(&etsects->lock, flags);
362
363 return 0;
364 }
365
ptp_gianfar_enable(struct ptp_clock_info * ptp,struct ptp_clock_request * rq,int on)366 static int ptp_gianfar_enable(struct ptp_clock_info *ptp,
367 struct ptp_clock_request *rq, int on)
368 {
369 struct etsects *etsects = container_of(ptp, struct etsects, caps);
370 unsigned long flags;
371 u32 bit, mask;
372
373 switch (rq->type) {
374 case PTP_CLK_REQ_EXTTS:
375 switch (rq->extts.index) {
376 case 0:
377 bit = ETS1EN;
378 break;
379 case 1:
380 bit = ETS2EN;
381 break;
382 default:
383 return -EINVAL;
384 }
385 spin_lock_irqsave(&etsects->lock, flags);
386 mask = gfar_read(&etsects->regs->tmr_temask);
387 if (on)
388 mask |= bit;
389 else
390 mask &= ~bit;
391 gfar_write(&etsects->regs->tmr_temask, mask);
392 spin_unlock_irqrestore(&etsects->lock, flags);
393 return 0;
394
395 case PTP_CLK_REQ_PPS:
396 spin_lock_irqsave(&etsects->lock, flags);
397 mask = gfar_read(&etsects->regs->tmr_temask);
398 if (on)
399 mask |= PP1EN;
400 else
401 mask &= ~PP1EN;
402 gfar_write(&etsects->regs->tmr_temask, mask);
403 spin_unlock_irqrestore(&etsects->lock, flags);
404 return 0;
405
406 default:
407 break;
408 }
409
410 return -EOPNOTSUPP;
411 }
412
413 static const struct ptp_clock_info ptp_gianfar_caps = {
414 .owner = THIS_MODULE,
415 .name = "gianfar clock",
416 .max_adj = 512000,
417 .n_alarm = 0,
418 .n_ext_ts = N_EXT_TS,
419 .n_per_out = 0,
420 .n_pins = 0,
421 .pps = 1,
422 .adjfine = ptp_gianfar_adjfine,
423 .adjtime = ptp_gianfar_adjtime,
424 .gettime64 = ptp_gianfar_gettime,
425 .settime64 = ptp_gianfar_settime,
426 .enable = ptp_gianfar_enable,
427 };
428
gianfar_ptp_probe(struct platform_device * dev)429 static int gianfar_ptp_probe(struct platform_device *dev)
430 {
431 struct device_node *node = dev->dev.of_node;
432 struct etsects *etsects;
433 struct timespec64 now;
434 int err = -ENOMEM;
435 u32 tmr_ctrl;
436 unsigned long flags;
437
438 etsects = kzalloc(sizeof(*etsects), GFP_KERNEL);
439 if (!etsects)
440 goto no_memory;
441
442 err = -ENODEV;
443
444 etsects->caps = ptp_gianfar_caps;
445
446 if (of_property_read_u32(node, "fsl,cksel", &etsects->cksel))
447 etsects->cksel = DEFAULT_CKSEL;
448
449 if (of_property_read_u32(node,
450 "fsl,tclk-period", &etsects->tclk_period) ||
451 of_property_read_u32(node,
452 "fsl,tmr-prsc", &etsects->tmr_prsc) ||
453 of_property_read_u32(node,
454 "fsl,tmr-add", &etsects->tmr_add) ||
455 of_property_read_u32(node,
456 "fsl,tmr-fiper1", &etsects->tmr_fiper1) ||
457 of_property_read_u32(node,
458 "fsl,tmr-fiper2", &etsects->tmr_fiper2) ||
459 of_property_read_u32(node,
460 "fsl,max-adj", &etsects->caps.max_adj)) {
461 pr_err("device tree node missing required elements\n");
462 goto no_node;
463 }
464
465 etsects->irq = platform_get_irq(dev, 0);
466
467 if (etsects->irq < 0) {
468 pr_err("irq not in device tree\n");
469 goto no_node;
470 }
471 if (request_irq(etsects->irq, isr, 0, DRIVER, etsects)) {
472 pr_err("request_irq failed\n");
473 goto no_node;
474 }
475
476 etsects->rsrc = platform_get_resource(dev, IORESOURCE_MEM, 0);
477 if (!etsects->rsrc) {
478 pr_err("no resource\n");
479 goto no_resource;
480 }
481 if (request_resource(&iomem_resource, etsects->rsrc)) {
482 pr_err("resource busy\n");
483 goto no_resource;
484 }
485
486 spin_lock_init(&etsects->lock);
487
488 etsects->regs = ioremap(etsects->rsrc->start,
489 resource_size(etsects->rsrc));
490 if (!etsects->regs) {
491 pr_err("ioremap ptp registers failed\n");
492 goto no_ioremap;
493 }
494 getnstimeofday64(&now);
495 ptp_gianfar_settime(&etsects->caps, &now);
496
497 tmr_ctrl =
498 (etsects->tclk_period & TCLK_PERIOD_MASK) << TCLK_PERIOD_SHIFT |
499 (etsects->cksel & CKSEL_MASK) << CKSEL_SHIFT;
500
501 spin_lock_irqsave(&etsects->lock, flags);
502
503 gfar_write(&etsects->regs->tmr_ctrl, tmr_ctrl);
504 gfar_write(&etsects->regs->tmr_add, etsects->tmr_add);
505 gfar_write(&etsects->regs->tmr_prsc, etsects->tmr_prsc);
506 gfar_write(&etsects->regs->tmr_fiper1, etsects->tmr_fiper1);
507 gfar_write(&etsects->regs->tmr_fiper2, etsects->tmr_fiper2);
508 set_alarm(etsects);
509 gfar_write(&etsects->regs->tmr_ctrl, tmr_ctrl|FIPERST|RTPE|TE|FRD);
510
511 spin_unlock_irqrestore(&etsects->lock, flags);
512
513 etsects->clock = ptp_clock_register(&etsects->caps, &dev->dev);
514 if (IS_ERR(etsects->clock)) {
515 err = PTR_ERR(etsects->clock);
516 goto no_clock;
517 }
518 gfar_phc_index = ptp_clock_index(etsects->clock);
519
520 platform_set_drvdata(dev, etsects);
521
522 return 0;
523
524 no_clock:
525 iounmap(etsects->regs);
526 no_ioremap:
527 release_resource(etsects->rsrc);
528 no_resource:
529 free_irq(etsects->irq, etsects);
530 no_node:
531 kfree(etsects);
532 no_memory:
533 return err;
534 }
535
gianfar_ptp_remove(struct platform_device * dev)536 static int gianfar_ptp_remove(struct platform_device *dev)
537 {
538 struct etsects *etsects = platform_get_drvdata(dev);
539
540 gfar_write(&etsects->regs->tmr_temask, 0);
541 gfar_write(&etsects->regs->tmr_ctrl, 0);
542
543 gfar_phc_index = -1;
544 ptp_clock_unregister(etsects->clock);
545 iounmap(etsects->regs);
546 release_resource(etsects->rsrc);
547 free_irq(etsects->irq, etsects);
548 kfree(etsects);
549
550 return 0;
551 }
552
553 static const struct of_device_id match_table[] = {
554 { .compatible = "fsl,etsec-ptp" },
555 {},
556 };
557 MODULE_DEVICE_TABLE(of, match_table);
558
559 static struct platform_driver gianfar_ptp_driver = {
560 .driver = {
561 .name = "gianfar_ptp",
562 .of_match_table = match_table,
563 },
564 .probe = gianfar_ptp_probe,
565 .remove = gianfar_ptp_remove,
566 };
567
568 module_platform_driver(gianfar_ptp_driver);
569
570 MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
571 MODULE_DESCRIPTION("PTP clock using the eTSEC");
572 MODULE_LICENSE("GPL");
573