tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
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#include <linux/device.h>
21#include <linux/hrtimer.h>
22#include <linux/init.h>
23#include <linux/interrupt.h>
24#include <linux/kernel.h>
25#include <linux/module.h>
26#include <linux/of.h>
27#include <linux/of_platform.h>
28#include <linux/timex.h>
29#include <linux/io.h>
30
31#include <linux/ptp_clock_kernel.h>
32
33#include "gianfar.h"
34
35/*
36 * gianfar ptp registers
37 * Generated by regen.tcl on Thu May 13 01:38:57 PM CEST 2010
38 */
39struct gianfar_ptp_registers {
40 u32 tmr_ctrl; /* Timer control register */
41 u32 tmr_tevent; /* Timestamp event register */
42 u32 tmr_temask; /* Timer event mask register */
43 u32 tmr_pevent; /* Timestamp event register */
44 u32 tmr_pemask; /* Timer event mask register */
45 u32 tmr_stat; /* Timestamp status register */
46 u32 tmr_cnt_h; /* Timer counter high register */
47 u32 tmr_cnt_l; /* Timer counter low register */
48 u32 tmr_add; /* Timer drift compensation addend register */
49 u32 tmr_acc; /* Timer accumulator register */
50 u32 tmr_prsc; /* Timer prescale */
51 u8 res1[4];
52 u32 tmroff_h; /* Timer offset high */
53 u32 tmroff_l; /* Timer offset low */
54 u8 res2[8];
55 u32 tmr_alarm1_h; /* Timer alarm 1 high register */
56 u32 tmr_alarm1_l; /* Timer alarm 1 high register */
57 u32 tmr_alarm2_h; /* Timer alarm 2 high register */
58 u32 tmr_alarm2_l; /* Timer alarm 2 high register */
59 u8 res3[48];
60 u32 tmr_fiper1; /* Timer fixed period interval */
61 u32 tmr_fiper2; /* Timer fixed period interval */
62 u32 tmr_fiper3; /* Timer fixed period interval */
63 u8 res4[20];
64 u32 tmr_etts1_h; /* Timestamp of general purpose external trigger */
65 u32 tmr_etts1_l; /* Timestamp of general purpose external trigger */
66 u32 tmr_etts2_h; /* Timestamp of general purpose external trigger */
67 u32 tmr_etts2_l; /* Timestamp of general purpose external trigger */
68};
69
70/* Bit definitions for the TMR_CTRL register */
71#define ALM1P (1<<31) /* Alarm1 output polarity */
72#define ALM2P (1<<30) /* Alarm2 output polarity */
73#define FS (1<<28) /* FIPER start indication */
74#define PP1L (1<<27) /* Fiper1 pulse loopback mode enabled. */
75#define PP2L (1<<26) /* Fiper2 pulse loopback mode enabled. */
76#define TCLK_PERIOD_SHIFT (16) /* 1588 timer reference clock period. */
77#define TCLK_PERIOD_MASK (0x3ff)
78#define RTPE (1<<15) /* Record Tx Timestamp to PAL Enable. */
79#define FRD (1<<14) /* FIPER Realignment Disable */
80#define ESFDP (1<<11) /* External Tx/Rx SFD Polarity. */
81#define ESFDE (1<<10) /* External Tx/Rx SFD Enable. */
82#define ETEP2 (1<<9) /* External trigger 2 edge polarity */
83#define ETEP1 (1<<8) /* External trigger 1 edge polarity */
84#define COPH (1<<7) /* Generated clock output phase. */
85#define CIPH (1<<6) /* External oscillator input clock phase */
86#define TMSR (1<<5) /* Timer soft reset. */
87#define BYP (1<<3) /* Bypass drift compensated clock */
88#define TE (1<<2) /* 1588 timer enable. */
89#define CKSEL_SHIFT (0) /* 1588 Timer reference clock source */
90#define CKSEL_MASK (0x3)
91
92/* Bit definitions for the TMR_TEVENT register */
93#define ETS2 (1<<25) /* External trigger 2 timestamp sampled */
94#define ETS1 (1<<24) /* External trigger 1 timestamp sampled */
95#define ALM2 (1<<17) /* Current time = alarm time register 2 */
96#define ALM1 (1<<16) /* Current time = alarm time register 1 */
97#define PP1 (1<<7) /* periodic pulse generated on FIPER1 */
98#define PP2 (1<<6) /* periodic pulse generated on FIPER2 */
99#define PP3 (1<<5) /* periodic pulse generated on FIPER3 */
100
101/* Bit definitions for the TMR_TEMASK register */
102#define ETS2EN (1<<25) /* External trigger 2 timestamp enable */
103#define ETS1EN (1<<24) /* External trigger 1 timestamp enable */
104#define ALM2EN (1<<17) /* Timer ALM2 event enable */
105#define ALM1EN (1<<16) /* Timer ALM1 event enable */
106#define PP1EN (1<<7) /* Periodic pulse event 1 enable */
107#define PP2EN (1<<6) /* Periodic pulse event 2 enable */
108
109/* Bit definitions for the TMR_PEVENT register */
110#define TXP2 (1<<9) /* PTP transmitted timestamp im TXTS2 */
111#define TXP1 (1<<8) /* PTP transmitted timestamp in TXTS1 */
112#define RXP (1<<0) /* PTP frame has been received */
113
114/* Bit definitions for the TMR_PEMASK register */
115#define TXP2EN (1<<9) /* Transmit PTP packet event 2 enable */
116#define TXP1EN (1<<8) /* Transmit PTP packet event 1 enable */
117#define RXPEN (1<<0) /* Receive PTP packet event enable */
118
119/* Bit definitions for the TMR_STAT register */
120#define STAT_VEC_SHIFT (0) /* Timer general purpose status vector */
121#define STAT_VEC_MASK (0x3f)
122
123/* Bit definitions for the TMR_PRSC register */
124#define PRSC_OCK_SHIFT (0) /* Output clock division/prescale factor. */
125#define PRSC_OCK_MASK (0xffff)
126
127
128#define DRIVER "gianfar_ptp"
129#define DEFAULT_CKSEL 1
130#define N_ALARM 1 /* first alarm is used internally to reset fipers */
131#define N_EXT_TS 2
132#define REG_SIZE sizeof(struct gianfar_ptp_registers)
133
134struct etsects {
135 struct gianfar_ptp_registers *regs;
136 spinlock_t lock; /* protects regs */
137 struct ptp_clock *clock;
138 struct ptp_clock_info caps;
139 struct resource *rsrc;
140 int irq;
141 u64 alarm_interval; /* for periodic alarm */
142 u64 alarm_value;
143 u32 tclk_period; /* nanoseconds */
144 u32 tmr_prsc;
145 u32 tmr_add;
146 u32 cksel;
147 u32 tmr_fiper1;
148 u32 tmr_fiper2;
149};
150
151/*
152 * Register access functions
153 */
154
155/* Caller must hold etsects->lock. */
156static u64 tmr_cnt_read(struct etsects *etsects)
157{
158 u64 ns;
159 u32 lo, hi;
160
161 lo = gfar_read(&etsects->regs->tmr_cnt_l);
162 hi = gfar_read(&etsects->regs->tmr_cnt_h);
163 ns = ((u64) hi) << 32;
164 ns |= lo;
165 return ns;
166}
167
168/* Caller must hold etsects->lock. */
169static void tmr_cnt_write(struct etsects *etsects, u64 ns)
170{
171 u32 hi = ns >> 32;
172 u32 lo = ns & 0xffffffff;
173
174 gfar_write(&etsects->regs->tmr_cnt_l, lo);
175 gfar_write(&etsects->regs->tmr_cnt_h, hi);
176}
177
178/* Caller must hold etsects->lock. */
179static void set_alarm(struct etsects *etsects)
180{
181 u64 ns;
182 u32 lo, hi;
183
184 ns = tmr_cnt_read(etsects) + 1500000000ULL;
185 ns = div_u64(ns, 1000000000UL) * 1000000000ULL;
186 ns -= etsects->tclk_period;
187 hi = ns >> 32;
188 lo = ns & 0xffffffff;
189 gfar_write(&etsects->regs->tmr_alarm1_l, lo);
190 gfar_write(&etsects->regs->tmr_alarm1_h, hi);
191}
192
193/* Caller must hold etsects->lock. */
194static void set_fipers(struct etsects *etsects)
195{
196 set_alarm(etsects);
197 gfar_write(&etsects->regs->tmr_fiper1, etsects->tmr_fiper1);
198 gfar_write(&etsects->regs->tmr_fiper2, etsects->tmr_fiper2);
199}
200
201/*
202 * Interrupt service routine
203 */
204
205static irqreturn_t isr(int irq, void *priv)
206{
207 struct etsects *etsects = priv;
208 struct ptp_clock_event event;
209 u64 ns;
210 u32 ack = 0, lo, hi, mask, val;
211
212 val = gfar_read(&etsects->regs->tmr_tevent);
213
214 if (val & ETS1) {
215 ack |= ETS1;
216 hi = gfar_read(&etsects->regs->tmr_etts1_h);
217 lo = gfar_read(&etsects->regs->tmr_etts1_l);
218 event.type = PTP_CLOCK_EXTTS;
219 event.index = 0;
220 event.timestamp = ((u64) hi) << 32;
221 event.timestamp |= lo;
222 ptp_clock_event(etsects->clock, &event);
223 }
224
225 if (val & ETS2) {
226 ack |= ETS2;
227 hi = gfar_read(&etsects->regs->tmr_etts2_h);
228 lo = gfar_read(&etsects->regs->tmr_etts2_l);
229 event.type = PTP_CLOCK_EXTTS;
230 event.index = 1;
231 event.timestamp = ((u64) hi) << 32;
232 event.timestamp |= lo;
233 ptp_clock_event(etsects->clock, &event);
234 }
235
236 if (val & ALM2) {
237 ack |= ALM2;
238 if (etsects->alarm_value) {
239 event.type = PTP_CLOCK_ALARM;
240 event.index = 0;
241 event.timestamp = etsects->alarm_value;
242 ptp_clock_event(etsects->clock, &event);
243 }
244 if (etsects->alarm_interval) {
245 ns = etsects->alarm_value + etsects->alarm_interval;
246 hi = ns >> 32;
247 lo = ns & 0xffffffff;
248 spin_lock(&etsects->lock);
249 gfar_write(&etsects->regs->tmr_alarm2_l, lo);
250 gfar_write(&etsects->regs->tmr_alarm2_h, hi);
251 spin_unlock(&etsects->lock);
252 etsects->alarm_value = ns;
253 } else {
254 gfar_write(&etsects->regs->tmr_tevent, ALM2);
255 spin_lock(&etsects->lock);
256 mask = gfar_read(&etsects->regs->tmr_temask);
257 mask &= ~ALM2EN;
258 gfar_write(&etsects->regs->tmr_temask, mask);
259 spin_unlock(&etsects->lock);
260 etsects->alarm_value = 0;
261 etsects->alarm_interval = 0;
262 }
263 }
264
265 if (val & PP1) {
266 ack |= PP1;
267 event.type = PTP_CLOCK_PPS;
268 ptp_clock_event(etsects->clock, &event);
269 }
270
271 if (ack) {
272 gfar_write(&etsects->regs->tmr_tevent, ack);
273 return IRQ_HANDLED;
274 } else
275 return IRQ_NONE;
276}
277
278/*
279 * PTP clock operations
280 */
281
282static int ptp_gianfar_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
283{
284 u64 adj;
285 u32 diff, tmr_add;
286 int neg_adj = 0;
287 struct etsects *etsects = container_of(ptp, struct etsects, caps);
288
289 if (ppb < 0) {
290 neg_adj = 1;
291 ppb = -ppb;
292 }
293 tmr_add = etsects->tmr_add;
294 adj = tmr_add;
295 adj *= ppb;
296 diff = div_u64(adj, 1000000000ULL);
297
298 tmr_add = neg_adj ? tmr_add - diff : tmr_add + diff;
299
300 gfar_write(&etsects->regs->tmr_add, tmr_add);
301
302 return 0;
303}
304
305static int ptp_gianfar_adjtime(struct ptp_clock_info *ptp, s64 delta)
306{
307 s64 now;
308 unsigned long flags;
309 struct etsects *etsects = container_of(ptp, struct etsects, caps);
310
311 spin_lock_irqsave(&etsects->lock, flags);
312
313 now = tmr_cnt_read(etsects);
314 now += delta;
315 tmr_cnt_write(etsects, now);
316
317 spin_unlock_irqrestore(&etsects->lock, flags);
318
319 set_fipers(etsects);
320
321 return 0;
322}
323
324static int ptp_gianfar_gettime(struct ptp_clock_info *ptp, struct timespec *ts)
325{
326 u64 ns;
327 u32 remainder;
328 unsigned long flags;
329 struct etsects *etsects = container_of(ptp, struct etsects, caps);
330
331 spin_lock_irqsave(&etsects->lock, flags);
332
333 ns = tmr_cnt_read(etsects);
334
335 spin_unlock_irqrestore(&etsects->lock, flags);
336
337 ts->tv_sec = div_u64_rem(ns, 1000000000, &remainder);
338 ts->tv_nsec = remainder;
339 return 0;
340}
341
342static int ptp_gianfar_settime(struct ptp_clock_info *ptp,
343 const struct timespec *ts)
344{
345 u64 ns;
346 unsigned long flags;
347 struct etsects *etsects = container_of(ptp, struct etsects, caps);
348
349 ns = ts->tv_sec * 1000000000ULL;
350 ns += ts->tv_nsec;
351
352 spin_lock_irqsave(&etsects->lock, flags);
353
354 tmr_cnt_write(etsects, ns);
355 set_fipers(etsects);
356
357 spin_unlock_irqrestore(&etsects->lock, flags);
358
359 return 0;
360}
361
362static int ptp_gianfar_enable(struct ptp_clock_info *ptp,
363 struct ptp_clock_request *rq, int on)
364{
365 struct etsects *etsects = container_of(ptp, struct etsects, caps);
366 unsigned long flags;
367 u32 bit, mask;
368
369 switch (rq->type) {
370 case PTP_CLK_REQ_EXTTS:
371 switch (rq->extts.index) {
372 case 0:
373 bit = ETS1EN;
374 break;
375 case 1:
376 bit = ETS2EN;
377 break;
378 default:
379 return -EINVAL;
380 }
381 spin_lock_irqsave(&etsects->lock, flags);
382 mask = gfar_read(&etsects->regs->tmr_temask);
383 if (on)
384 mask |= bit;
385 else
386 mask &= ~bit;
387 gfar_write(&etsects->regs->tmr_temask, mask);
388 spin_unlock_irqrestore(&etsects->lock, flags);
389 return 0;
390
391 case PTP_CLK_REQ_PPS:
392 spin_lock_irqsave(&etsects->lock, flags);
393 mask = gfar_read(&etsects->regs->tmr_temask);
394 if (on)
395 mask |= PP1EN;
396 else
397 mask &= ~PP1EN;
398 gfar_write(&etsects->regs->tmr_temask, mask);
399 spin_unlock_irqrestore(&etsects->lock, flags);
400 return 0;
401
402 default:
403 break;
404 }
405
406 return -EOPNOTSUPP;
407}
408
409static struct ptp_clock_info ptp_gianfar_caps = {
410 .owner = THIS_MODULE,
411 .name = "gianfar clock",
412 .max_adj = 512000,
413 .n_alarm = N_ALARM,
414 .n_ext_ts = N_EXT_TS,
415 .n_per_out = 0,
416 .pps = 1,
417 .adjfreq = ptp_gianfar_adjfreq,
418 .adjtime = ptp_gianfar_adjtime,
419 .gettime = ptp_gianfar_gettime,
420 .settime = ptp_gianfar_settime,
421 .enable = ptp_gianfar_enable,
422};
423
424/* OF device tree */
425
426static int get_of_u32(struct device_node *node, char *str, u32 *val)
427{
428 int plen;
429 const u32 *prop = of_get_property(node, str, &plen);
430
431 if (!prop || plen != sizeof(*prop))
432 return -1;
433 *val = *prop;
434 return 0;
435}
436
437static int gianfar_ptp_probe(struct platform_device *dev)
438{
439 struct device_node *node = dev->dev.of_node;
440 struct etsects *etsects;
441 struct timespec now;
442 int err = -ENOMEM;
443 u32 tmr_ctrl;
444 unsigned long flags;
445
446 etsects = kzalloc(sizeof(*etsects), GFP_KERNEL);
447 if (!etsects)
448 goto no_memory;
449
450 err = -ENODEV;
451
452 etsects->caps = ptp_gianfar_caps;
453 etsects->cksel = DEFAULT_CKSEL;
454
455 if (get_of_u32(node, "fsl,tclk-period", &etsects->tclk_period) ||
456 get_of_u32(node, "fsl,tmr-prsc", &etsects->tmr_prsc) ||
457 get_of_u32(node, "fsl,tmr-add", &etsects->tmr_add) ||
458 get_of_u32(node, "fsl,tmr-fiper1", &etsects->tmr_fiper1) ||
459 get_of_u32(node, "fsl,tmr-fiper2", &etsects->tmr_fiper2) ||
460 get_of_u32(node, "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 == NO_IRQ) {
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(&ioport_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 getnstimeofday(&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|FS|RTPE|TE|FRD);
510
511 spin_unlock_irqrestore(&etsects->lock, flags);
512
513 etsects->clock = ptp_clock_register(&etsects->caps);
514 if (IS_ERR(etsects->clock)) {
515 err = PTR_ERR(etsects->clock);
516 goto no_clock;
517 }
518
519 dev_set_drvdata(&dev->dev, etsects);
520
521 return 0;
522
523no_clock:
524no_ioremap:
525 release_resource(etsects->rsrc);
526no_resource:
527 free_irq(etsects->irq, etsects);
528no_node:
529 kfree(etsects);
530no_memory:
531 return err;
532}
533
534static int gianfar_ptp_remove(struct platform_device *dev)
535{
536 struct etsects *etsects = dev_get_drvdata(&dev->dev);
537
538 gfar_write(&etsects->regs->tmr_temask, 0);
539 gfar_write(&etsects->regs->tmr_ctrl, 0);
540
541 ptp_clock_unregister(etsects->clock);
542 iounmap(etsects->regs);
543 release_resource(etsects->rsrc);
544 free_irq(etsects->irq, etsects);
545 kfree(etsects);
546
547 return 0;
548}
549
550static struct of_device_id match_table[] = {
551 { .compatible = "fsl,etsec-ptp" },
552 {},
553};
554
555static struct platform_driver gianfar_ptp_driver = {
556 .driver = {
557 .name = "gianfar_ptp",
558 .of_match_table = match_table,
559 .owner = THIS_MODULE,
560 },
561 .probe = gianfar_ptp_probe,
562 .remove = gianfar_ptp_remove,
563};
564
565/* module operations */
566
567static int __init ptp_gianfar_init(void)
568{
569 return platform_driver_register(&gianfar_ptp_driver);
570}
571
572module_init(ptp_gianfar_init);
573
574static void __exit ptp_gianfar_exit(void)
575{
576 platform_driver_unregister(&gianfar_ptp_driver);
577}
578
579module_exit(ptp_gianfar_exit);
580
581MODULE_AUTHOR("Richard Cochran <richard.cochran@omicron.at>");
582MODULE_DESCRIPTION("PTP clock using the eTSEC");
583MODULE_LICENSE("GPL");