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/init.h>
26 #include <linux/interrupt.h>
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/of.h>
30 #include <linux/of_platform.h>
31 #include <linux/timex.h>
32 #include <linux/io.h>
33
34 #include <linux/ptp_clock_kernel.h>
35
36 #include "gianfar.h"
37
38 /*
39 * gianfar ptp registers
40 * Generated by regen.tcl on Thu May 13 01:38:57 PM CEST 2010
41 */
42 struct gianfar_ptp_registers {
43 u32 tmr_ctrl; /* Timer control register */
44 u32 tmr_tevent; /* Timestamp event register */
45 u32 tmr_temask; /* Timer event mask register */
46 u32 tmr_pevent; /* Timestamp event register */
47 u32 tmr_pemask; /* Timer event mask register */
48 u32 tmr_stat; /* Timestamp status register */
49 u32 tmr_cnt_h; /* Timer counter high register */
50 u32 tmr_cnt_l; /* Timer counter low register */
51 u32 tmr_add; /* Timer drift compensation addend register */
52 u32 tmr_acc; /* Timer accumulator register */
53 u32 tmr_prsc; /* Timer prescale */
54 u8 res1[4];
55 u32 tmroff_h; /* Timer offset high */
56 u32 tmroff_l; /* Timer offset low */
57 u8 res2[8];
58 u32 tmr_alarm1_h; /* Timer alarm 1 high register */
59 u32 tmr_alarm1_l; /* Timer alarm 1 high register */
60 u32 tmr_alarm2_h; /* Timer alarm 2 high register */
61 u32 tmr_alarm2_l; /* Timer alarm 2 high register */
62 u8 res3[48];
63 u32 tmr_fiper1; /* Timer fixed period interval */
64 u32 tmr_fiper2; /* Timer fixed period interval */
65 u32 tmr_fiper3; /* Timer fixed period interval */
66 u8 res4[20];
67 u32 tmr_etts1_h; /* Timestamp of general purpose external trigger */
68 u32 tmr_etts1_l; /* Timestamp of general purpose external trigger */
69 u32 tmr_etts2_h; /* Timestamp of general purpose external trigger */
70 u32 tmr_etts2_l; /* Timestamp of general purpose external trigger */
71 };
72
73 /* Bit definitions for the TMR_CTRL register */
74 #define ALM1P (1<<31) /* Alarm1 output polarity */
75 #define ALM2P (1<<30) /* Alarm2 output polarity */
76 #define FS (1<<28) /* FIPER start indication */
77 #define PP1L (1<<27) /* Fiper1 pulse loopback mode enabled. */
78 #define PP2L (1<<26) /* Fiper2 pulse loopback mode enabled. */
79 #define TCLK_PERIOD_SHIFT (16) /* 1588 timer reference clock period. */
80 #define TCLK_PERIOD_MASK (0x3ff)
81 #define RTPE (1<<15) /* Record Tx Timestamp to PAL Enable. */
82 #define FRD (1<<14) /* FIPER Realignment Disable */
83 #define ESFDP (1<<11) /* External Tx/Rx SFD Polarity. */
84 #define ESFDE (1<<10) /* External Tx/Rx SFD Enable. */
85 #define ETEP2 (1<<9) /* External trigger 2 edge polarity */
86 #define ETEP1 (1<<8) /* External trigger 1 edge polarity */
87 #define COPH (1<<7) /* Generated clock output phase. */
88 #define CIPH (1<<6) /* External oscillator input clock phase */
89 #define TMSR (1<<5) /* Timer soft reset. */
90 #define BYP (1<<3) /* Bypass drift compensated clock */
91 #define TE (1<<2) /* 1588 timer enable. */
92 #define CKSEL_SHIFT (0) /* 1588 Timer reference clock source */
93 #define CKSEL_MASK (0x3)
94
95 /* Bit definitions for the TMR_TEVENT register */
96 #define ETS2 (1<<25) /* External trigger 2 timestamp sampled */
97 #define ETS1 (1<<24) /* External trigger 1 timestamp sampled */
98 #define ALM2 (1<<17) /* Current time = alarm time register 2 */
99 #define ALM1 (1<<16) /* Current time = alarm time register 1 */
100 #define PP1 (1<<7) /* periodic pulse generated on FIPER1 */
101 #define PP2 (1<<6) /* periodic pulse generated on FIPER2 */
102 #define PP3 (1<<5) /* periodic pulse generated on FIPER3 */
103
104 /* Bit definitions for the TMR_TEMASK register */
105 #define ETS2EN (1<<25) /* External trigger 2 timestamp enable */
106 #define ETS1EN (1<<24) /* External trigger 1 timestamp enable */
107 #define ALM2EN (1<<17) /* Timer ALM2 event enable */
108 #define ALM1EN (1<<16) /* Timer ALM1 event enable */
109 #define PP1EN (1<<7) /* Periodic pulse event 1 enable */
110 #define PP2EN (1<<6) /* Periodic pulse event 2 enable */
111
112 /* Bit definitions for the TMR_PEVENT register */
113 #define TXP2 (1<<9) /* PTP transmitted timestamp im TXTS2 */
114 #define TXP1 (1<<8) /* PTP transmitted timestamp in TXTS1 */
115 #define RXP (1<<0) /* PTP frame has been received */
116
117 /* Bit definitions for the TMR_PEMASK register */
118 #define TXP2EN (1<<9) /* Transmit PTP packet event 2 enable */
119 #define TXP1EN (1<<8) /* Transmit PTP packet event 1 enable */
120 #define RXPEN (1<<0) /* Receive PTP packet event enable */
121
122 /* Bit definitions for the TMR_STAT register */
123 #define STAT_VEC_SHIFT (0) /* Timer general purpose status vector */
124 #define STAT_VEC_MASK (0x3f)
125
126 /* Bit definitions for the TMR_PRSC register */
127 #define PRSC_OCK_SHIFT (0) /* Output clock division/prescale factor. */
128 #define PRSC_OCK_MASK (0xffff)
129
130
131 #define DRIVER "gianfar_ptp"
132 #define DEFAULT_CKSEL 1
133 #define N_EXT_TS 2
134 #define REG_SIZE sizeof(struct gianfar_ptp_registers)
135
136 struct etsects {
137 struct gianfar_ptp_registers *regs;
138 spinlock_t lock; /* protects regs */
139 struct ptp_clock *clock;
140 struct ptp_clock_info caps;
141 struct resource *rsrc;
142 int irq;
143 u64 alarm_interval; /* for periodic alarm */
144 u64 alarm_value;
145 u32 tclk_period; /* nanoseconds */
146 u32 tmr_prsc;
147 u32 tmr_add;
148 u32 cksel;
149 u32 tmr_fiper1;
150 u32 tmr_fiper2;
151 };
152
153 /*
154 * Register access functions
155 */
156
157 /* Caller must hold etsects->lock. */
tmr_cnt_read(struct etsects * etsects)158 static u64 tmr_cnt_read(struct etsects *etsects)
159 {
160 u64 ns;
161 u32 lo, hi;
162
163 lo = gfar_read(&etsects->regs->tmr_cnt_l);
164 hi = gfar_read(&etsects->regs->tmr_cnt_h);
165 ns = ((u64) hi) << 32;
166 ns |= lo;
167 return ns;
168 }
169
170 /* Caller must hold etsects->lock. */
tmr_cnt_write(struct etsects * etsects,u64 ns)171 static void tmr_cnt_write(struct etsects *etsects, u64 ns)
172 {
173 u32 hi = ns >> 32;
174 u32 lo = ns & 0xffffffff;
175
176 gfar_write(&etsects->regs->tmr_cnt_l, lo);
177 gfar_write(&etsects->regs->tmr_cnt_h, hi);
178 }
179
180 /* Caller must hold etsects->lock. */
set_alarm(struct etsects * etsects)181 static void set_alarm(struct etsects *etsects)
182 {
183 u64 ns;
184 u32 lo, hi;
185
186 ns = tmr_cnt_read(etsects) + 1500000000ULL;
187 ns = div_u64(ns, 1000000000UL) * 1000000000ULL;
188 ns -= etsects->tclk_period;
189 hi = ns >> 32;
190 lo = ns & 0xffffffff;
191 gfar_write(&etsects->regs->tmr_alarm1_l, lo);
192 gfar_write(&etsects->regs->tmr_alarm1_h, hi);
193 }
194
195 /* Caller must hold etsects->lock. */
set_fipers(struct etsects * etsects)196 static void set_fipers(struct etsects *etsects)
197 {
198 set_alarm(etsects);
199 gfar_write(&etsects->regs->tmr_fiper1, etsects->tmr_fiper1);
200 gfar_write(&etsects->regs->tmr_fiper2, etsects->tmr_fiper2);
201 }
202
203 /*
204 * Interrupt service routine
205 */
206
isr(int irq,void * priv)207 static irqreturn_t isr(int irq, void *priv)
208 {
209 struct etsects *etsects = priv;
210 struct ptp_clock_event event;
211 u64 ns;
212 u32 ack = 0, lo, hi, mask, val;
213
214 val = gfar_read(&etsects->regs->tmr_tevent);
215
216 if (val & ETS1) {
217 ack |= ETS1;
218 hi = gfar_read(&etsects->regs->tmr_etts1_h);
219 lo = gfar_read(&etsects->regs->tmr_etts1_l);
220 event.type = PTP_CLOCK_EXTTS;
221 event.index = 0;
222 event.timestamp = ((u64) hi) << 32;
223 event.timestamp |= lo;
224 ptp_clock_event(etsects->clock, &event);
225 }
226
227 if (val & ETS2) {
228 ack |= ETS2;
229 hi = gfar_read(&etsects->regs->tmr_etts2_h);
230 lo = gfar_read(&etsects->regs->tmr_etts2_l);
231 event.type = PTP_CLOCK_EXTTS;
232 event.index = 1;
233 event.timestamp = ((u64) hi) << 32;
234 event.timestamp |= lo;
235 ptp_clock_event(etsects->clock, &event);
236 }
237
238 if (val & ALM2) {
239 ack |= ALM2;
240 if (etsects->alarm_value) {
241 event.type = PTP_CLOCK_ALARM;
242 event.index = 0;
243 event.timestamp = etsects->alarm_value;
244 ptp_clock_event(etsects->clock, &event);
245 }
246 if (etsects->alarm_interval) {
247 ns = etsects->alarm_value + etsects->alarm_interval;
248 hi = ns >> 32;
249 lo = ns & 0xffffffff;
250 spin_lock(&etsects->lock);
251 gfar_write(&etsects->regs->tmr_alarm2_l, lo);
252 gfar_write(&etsects->regs->tmr_alarm2_h, hi);
253 spin_unlock(&etsects->lock);
254 etsects->alarm_value = ns;
255 } else {
256 gfar_write(&etsects->regs->tmr_tevent, ALM2);
257 spin_lock(&etsects->lock);
258 mask = gfar_read(&etsects->regs->tmr_temask);
259 mask &= ~ALM2EN;
260 gfar_write(&etsects->regs->tmr_temask, mask);
261 spin_unlock(&etsects->lock);
262 etsects->alarm_value = 0;
263 etsects->alarm_interval = 0;
264 }
265 }
266
267 if (val & PP1) {
268 ack |= PP1;
269 event.type = PTP_CLOCK_PPS;
270 ptp_clock_event(etsects->clock, &event);
271 }
272
273 if (ack) {
274 gfar_write(&etsects->regs->tmr_tevent, ack);
275 return IRQ_HANDLED;
276 } else
277 return IRQ_NONE;
278 }
279
280 /*
281 * PTP clock operations
282 */
283
ptp_gianfar_adjfreq(struct ptp_clock_info * ptp,s32 ppb)284 static int ptp_gianfar_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
285 {
286 u64 adj;
287 u32 diff, tmr_add;
288 int neg_adj = 0;
289 struct etsects *etsects = container_of(ptp, struct etsects, caps);
290
291 if (ppb < 0) {
292 neg_adj = 1;
293 ppb = -ppb;
294 }
295 tmr_add = etsects->tmr_add;
296 adj = tmr_add;
297 adj *= ppb;
298 diff = div_u64(adj, 1000000000ULL);
299
300 tmr_add = neg_adj ? tmr_add - diff : tmr_add + diff;
301
302 gfar_write(&etsects->regs->tmr_add, tmr_add);
303
304 return 0;
305 }
306
ptp_gianfar_adjtime(struct ptp_clock_info * ptp,s64 delta)307 static int ptp_gianfar_adjtime(struct ptp_clock_info *ptp, s64 delta)
308 {
309 s64 now;
310 unsigned long flags;
311 struct etsects *etsects = container_of(ptp, struct etsects, caps);
312
313 spin_lock_irqsave(&etsects->lock, flags);
314
315 now = tmr_cnt_read(etsects);
316 now += delta;
317 tmr_cnt_write(etsects, now);
318
319 spin_unlock_irqrestore(&etsects->lock, flags);
320
321 set_fipers(etsects);
322
323 return 0;
324 }
325
ptp_gianfar_gettime(struct ptp_clock_info * ptp,struct timespec * ts)326 static int ptp_gianfar_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
327 {
328 u64 ns;
329 u32 remainder;
330 unsigned long flags;
331 struct etsects *etsects = container_of(ptp, struct etsects, caps);
332
333 spin_lock_irqsave(&etsects->lock, flags);
334
335 ns = tmr_cnt_read(etsects);
336
337 spin_unlock_irqrestore(&etsects->lock, flags);
338
339 ts->tv_sec = div_u64_rem(ns, 1000000000, &remainder);
340 ts->tv_nsec = remainder;
341 return 0;
342 }
343
ptp_gianfar_settime(struct ptp_clock_info * ptp,const struct timespec * ts)344 static int ptp_gianfar_settime(struct ptp_clock_info *ptp,
345 const struct timespec *ts)
346 {
347 u64 ns;
348 unsigned long flags;
349 struct etsects *etsects = container_of(ptp, struct etsects, caps);
350
351 ns = ts->tv_sec * 1000000000ULL;
352 ns += ts->tv_nsec;
353
354 spin_lock_irqsave(&etsects->lock, flags);
355
356 tmr_cnt_write(etsects, ns);
357 set_fipers(etsects);
358
359 spin_unlock_irqrestore(&etsects->lock, flags);
360
361 return 0;
362 }
363
ptp_gianfar_enable(struct ptp_clock_info * ptp,struct ptp_clock_request * rq,int on)364 static int ptp_gianfar_enable(struct ptp_clock_info *ptp,
365 struct ptp_clock_request *rq, int on)
366 {
367 struct etsects *etsects = container_of(ptp, struct etsects, caps);
368 unsigned long flags;
369 u32 bit, mask;
370
371 switch (rq->type) {
372 case PTP_CLK_REQ_EXTTS:
373 switch (rq->extts.index) {
374 case 0:
375 bit = ETS1EN;
376 break;
377 case 1:
378 bit = ETS2EN;
379 break;
380 default:
381 return -EINVAL;
382 }
383 spin_lock_irqsave(&etsects->lock, flags);
384 mask = gfar_read(&etsects->regs->tmr_temask);
385 if (on)
386 mask |= bit;
387 else
388 mask &= ~bit;
389 gfar_write(&etsects->regs->tmr_temask, mask);
390 spin_unlock_irqrestore(&etsects->lock, flags);
391 return 0;
392
393 case PTP_CLK_REQ_PPS:
394 spin_lock_irqsave(&etsects->lock, flags);
395 mask = gfar_read(&etsects->regs->tmr_temask);
396 if (on)
397 mask |= PP1EN;
398 else
399 mask &= ~PP1EN;
400 gfar_write(&etsects->regs->tmr_temask, mask);
401 spin_unlock_irqrestore(&etsects->lock, flags);
402 return 0;
403
404 default:
405 break;
406 }
407
408 return -EOPNOTSUPP;
409 }
410
411 static struct ptp_clock_info ptp_gianfar_caps = {
412 .owner = THIS_MODULE,
413 .name = "gianfar clock",
414 .max_adj = 512000,
415 .n_alarm = 0,
416 .n_ext_ts = N_EXT_TS,
417 .n_per_out = 0,
418 .pps = 1,
419 .adjfreq = ptp_gianfar_adjfreq,
420 .adjtime = ptp_gianfar_adjtime,
421 .gettime = ptp_gianfar_gettime,
422 .settime = ptp_gianfar_settime,
423 .enable = ptp_gianfar_enable,
424 };
425
426 /* OF device tree */
427
get_of_u32(struct device_node * node,char * str,u32 * val)428 static int get_of_u32(struct device_node *node, char *str, u32 *val)
429 {
430 int plen;
431 const u32 *prop = of_get_property(node, str, &plen);
432
433 if (!prop || plen != sizeof(*prop))
434 return -1;
435 *val = *prop;
436 return 0;
437 }
438
gianfar_ptp_probe(struct platform_device * dev)439 static int gianfar_ptp_probe(struct platform_device *dev)
440 {
441 struct device_node *node = dev->dev.of_node;
442 struct etsects *etsects;
443 struct timespec now;
444 int err = -ENOMEM;
445 u32 tmr_ctrl;
446 unsigned long flags;
447
448 etsects = kzalloc(sizeof(*etsects), GFP_KERNEL);
449 if (!etsects)
450 goto no_memory;
451
452 err = -ENODEV;
453
454 etsects->caps = ptp_gianfar_caps;
455 etsects->cksel = DEFAULT_CKSEL;
456
457 if (get_of_u32(node, "fsl,tclk-period", &etsects->tclk_period) ||
458 get_of_u32(node, "fsl,tmr-prsc", &etsects->tmr_prsc) ||
459 get_of_u32(node, "fsl,tmr-add", &etsects->tmr_add) ||
460 get_of_u32(node, "fsl,tmr-fiper1", &etsects->tmr_fiper1) ||
461 get_of_u32(node, "fsl,tmr-fiper2", &etsects->tmr_fiper2) ||
462 get_of_u32(node, "fsl,max-adj", &etsects->caps.max_adj)) {
463 pr_err("device tree node missing required elements\n");
464 goto no_node;
465 }
466
467 etsects->irq = platform_get_irq(dev, 0);
468
469 if (etsects->irq == NO_IRQ) {
470 pr_err("irq not in device tree\n");
471 goto no_node;
472 }
473 if (request_irq(etsects->irq, isr, 0, DRIVER, etsects)) {
474 pr_err("request_irq failed\n");
475 goto no_node;
476 }
477
478 etsects->rsrc = platform_get_resource(dev, IORESOURCE_MEM, 0);
479 if (!etsects->rsrc) {
480 pr_err("no resource\n");
481 goto no_resource;
482 }
483 if (request_resource(&iomem_resource, etsects->rsrc)) {
484 pr_err("resource busy\n");
485 goto no_resource;
486 }
487
488 spin_lock_init(&etsects->lock);
489
490 etsects->regs = ioremap(etsects->rsrc->start,
491 resource_size(etsects->rsrc));
492 if (!etsects->regs) {
493 pr_err("ioremap ptp registers failed\n");
494 goto no_ioremap;
495 }
496 getnstimeofday(&now);
497 ptp_gianfar_settime(&etsects->caps, &now);
498
499 tmr_ctrl =
500 (etsects->tclk_period & TCLK_PERIOD_MASK) << TCLK_PERIOD_SHIFT |
501 (etsects->cksel & CKSEL_MASK) << CKSEL_SHIFT;
502
503 spin_lock_irqsave(&etsects->lock, flags);
504
505 gfar_write(&etsects->regs->tmr_ctrl, tmr_ctrl);
506 gfar_write(&etsects->regs->tmr_add, etsects->tmr_add);
507 gfar_write(&etsects->regs->tmr_prsc, etsects->tmr_prsc);
508 gfar_write(&etsects->regs->tmr_fiper1, etsects->tmr_fiper1);
509 gfar_write(&etsects->regs->tmr_fiper2, etsects->tmr_fiper2);
510 set_alarm(etsects);
511 gfar_write(&etsects->regs->tmr_ctrl, tmr_ctrl|FS|RTPE|TE|FRD);
512
513 spin_unlock_irqrestore(&etsects->lock, flags);
514
515 etsects->clock = ptp_clock_register(&etsects->caps, &dev->dev);
516 if (IS_ERR(etsects->clock)) {
517 err = PTR_ERR(etsects->clock);
518 goto no_clock;
519 }
520 gfar_phc_index = ptp_clock_index(etsects->clock);
521
522 dev_set_drvdata(&dev->dev, etsects);
523
524 return 0;
525
526 no_clock:
527 iounmap(etsects->regs);
528 no_ioremap:
529 release_resource(etsects->rsrc);
530 no_resource:
531 free_irq(etsects->irq, etsects);
532 no_node:
533 kfree(etsects);
534 no_memory:
535 return err;
536 }
537
gianfar_ptp_remove(struct platform_device * dev)538 static int gianfar_ptp_remove(struct platform_device *dev)
539 {
540 struct etsects *etsects = dev_get_drvdata(&dev->dev);
541
542 gfar_write(&etsects->regs->tmr_temask, 0);
543 gfar_write(&etsects->regs->tmr_ctrl, 0);
544
545 gfar_phc_index = -1;
546 ptp_clock_unregister(etsects->clock);
547 iounmap(etsects->regs);
548 release_resource(etsects->rsrc);
549 free_irq(etsects->irq, etsects);
550 kfree(etsects);
551
552 return 0;
553 }
554
555 static struct of_device_id match_table[] = {
556 { .compatible = "fsl,etsec-ptp" },
557 {},
558 };
559
560 static struct platform_driver gianfar_ptp_driver = {
561 .driver = {
562 .name = "gianfar_ptp",
563 .of_match_table = match_table,
564 .owner = THIS_MODULE,
565 },
566 .probe = gianfar_ptp_probe,
567 .remove = gianfar_ptp_remove,
568 };
569
570 module_platform_driver(gianfar_ptp_driver);
571
572 MODULE_AUTHOR("Richard Cochran <richardcochran@gmail.com>");
573 MODULE_DESCRIPTION("PTP clock using the eTSEC");
574 MODULE_LICENSE("GPL");
575