Documentation/ptp/testptp.c

   1 /*
   2  * PTP 1588 clock support - User space test program
   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 <errno.h>
  21 #include <fcntl.h>
  22 #include <math.h>
  23 #include <signal.h>
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <sys/ioctl.h>
  28 #include <sys/mman.h>
  29 #include <sys/stat.h>
  30 #include <sys/time.h>
  31 #include <sys/timex.h>
  32 #include <sys/types.h>
  33 #include <time.h>
  34 #include <unistd.h>
  35
  36 #include <linux/ptp_clock.h>
  37
  38 #define DEVICE "/dev/ptp0"
  39
  40 #ifndef ADJ_SETOFFSET
  41 #define ADJ_SETOFFSET 0x0100
  42 #endif
  43
  44 #ifndef CLOCK_INVALID
  45 #define CLOCK_INVALID -1
  46 #endif
  47
  48 /* When glibc offers the syscall, this will go away. */
  49 #include <sys/syscall.h>
  50 static int clock_adjtime(clockid_t id, struct timex *tx)
  51 {
  52         return syscall(__NR_clock_adjtime, id, tx);
  53 }
  54
  55 static clockid_t get_clockid(int fd)
  56 {
  57 #define CLOCKFD 3
  58 #define FD_TO_CLOCKID(fd)       ((~(clockid_t) (fd) << 3) | CLOCKFD)
  59
  60         return FD_TO_CLOCKID(fd);
  61 }
  62
  63 static void handle_alarm(int s)
  64 {
  65         printf("received signal %d\n", s);
  66 }
  67
  68 static int install_handler(int signum, void (*handler)(int))
  69 {
  70         struct sigaction action;
  71         sigset_t mask;
  72
  73         /* Unblock the signal. */
  74         sigemptyset(&mask);
  75         sigaddset(&mask, signum);
  76         sigprocmask(SIG_UNBLOCK, &mask, NULL);
  77
  78         /* Install the signal handler. */
  79         action.sa_handler = handler;
  80         action.sa_flags = 0;
  81         sigemptyset(&action.sa_mask);
  82         sigaction(signum, &action, NULL);
  83
  84         return 0;
  85 }
  86
  87 static long ppb_to_scaled_ppm(int ppb)
  88 {
  89         /*
  90          * The 'freq' field in the 'struct timex' is in parts per
  91          * million, but with a 16 bit binary fractional field.
  92          * Instead of calculating either one of
  93          *
  94          *    scaled_ppm = (ppb / 1000) << 16  [1]
  95          *    scaled_ppm = (ppb << 16) / 1000  [2]
  96          *
  97          * we simply use double precision math, in order to avoid the
  98          * truncation in [1] and the possible overflow in [2].
  99          */
 100         return (long) (ppb * 65.536);
 101 }
 102
 103 static int64_t pctns(struct ptp_clock_time *t)
 104 {
 105         return t->sec * 1000000000LL + t->nsec;
 106 }
 107
 108 static void usage(char *progname)
 109 {
 110         fprintf(stderr,
 111                 "usage: %s [options]\n"
 112                 " -a val     request a one-shot alarm after 'val' seconds\n"
 113                 " -A val     request a periodic alarm every 'val' seconds\n"
 114                 " -c         query the ptp clock's capabilities\n"
 115                 " -d name    device to open\n"
 116                 " -e val     read 'val' external time stamp events\n"
 117                 " -f val     adjust the ptp clock frequency by 'val' ppb\n"
 118                 " -g         get the ptp clock time\n"
 119                 " -h         prints this message\n"
 120                 " -i val     index for event/trigger\n"
 121                 " -k val     measure the time offset between system and phc clock\n"
 122                 "            for 'val' times (Maximum 25)\n"
 123                 " -p val     enable output with a period of 'val' nanoseconds\n"
 124                 " -P val     enable or disable (val=1|0) the system clock PPS\n"
 125                 " -s         set the ptp clock time from the system time\n"
 126                 " -S         set the system time from the ptp clock time\n"
 127                 " -t val     shift the ptp clock time by 'val' seconds\n",
 128                 progname);
 129 }
 130
 131 int main(int argc, char *argv[])
 132 {
 133         struct ptp_clock_caps caps;
 134         struct ptp_extts_event event;
 135         struct ptp_extts_request extts_request;
 136         struct ptp_perout_request perout_request;
 137         struct timespec ts;
 138         struct timex tx;
 139
 140         static timer_t timerid;
 141         struct itimerspec timeout;
 142         struct sigevent sigevent;
 143
 144         struct ptp_clock_time *pct;
 145         struct ptp_sys_offset *sysoff;
 146
 147
 148         char *progname;
 149         int i, c, cnt, fd;
 150
 151         char *device = DEVICE;
 152         clockid_t clkid;
 153         int adjfreq = 0x7fffffff;
 154         int adjtime = 0;
 155         int capabilities = 0;
 156         int extts = 0;
 157         int gettime = 0;
 158         int index = 0;
 159         int oneshot = 0;
 160         int pct_offset = 0;
 161         int n_samples = 0;
 162         int periodic = 0;
 163         int perout = -1;
 164         int pps = -1;
 165         int settime = 0;
 166
 167         int64_t t1, t2, tp;
 168         int64_t interval, offset;
 169
 170         progname = strrchr(argv[0], '/');
 171         progname = progname ? 1+progname : argv[0];
 172         while (EOF != (c = getopt(argc, argv, "a:A:cd:e:f:ghi:k:p:P:sSt:v"))) {
 173                 switch (c) {
 174                 case 'a':
 175                         oneshot = atoi(optarg);
 176                         break;
 177                 case 'A':
 178                         periodic = atoi(optarg);
 179                         break;
 180                 case 'c':
 181                         capabilities = 1;
 182                         break;
 183                 case 'd':
 184                         device = optarg;
 185                         break;
 186                 case 'e':
 187                         extts = atoi(optarg);
 188                         break;
 189                 case 'f':
 190                         adjfreq = atoi(optarg);
 191                         break;
 192                 case 'g':
 193                         gettime = 1;
 194                         break;
 195                 case 'i':
 196                         index = atoi(optarg);
 197                         break;
 198                 case 'k':
 199                         pct_offset = 1;
 200                         n_samples = atoi(optarg);
 201                         break;
 202                 case 'p':
 203                         perout = atoi(optarg);
 204                         break;
 205                 case 'P':
 206                         pps = atoi(optarg);
 207                         break;
 208                 case 's':
 209                         settime = 1;
 210                         break;
 211                 case 'S':
 212                         settime = 2;
 213                         break;
 214                 case 't':
 215                         adjtime = atoi(optarg);
 216                         break;
 217                 case 'h':
 218                         usage(progname);
 219                         return 0;
 220                 case '?':
 221                 default:
 222                         usage(progname);
 223                         return -1;
 224                 }
 225         }
 226
 227         fd = open(device, O_RDWR);
 228         if (fd < 0) {
 229                 fprintf(stderr, "opening %s: %s\n", device, strerror(errno));
 230                 return -1;
 231         }
 232
 233         clkid = get_clockid(fd);
 234         if (CLOCK_INVALID == clkid) {
 235                 fprintf(stderr, "failed to read clock id\n");
 236                 return -1;
 237         }
 238
 239         if (capabilities) {
 240                 if (ioctl(fd, PTP_CLOCK_GETCAPS, &caps)) {
 241                         perror("PTP_CLOCK_GETCAPS");
 242                 } else {
 243                         printf("capabilities:\n"
 244                                "  %d maximum frequency adjustment (ppb)\n"
 245                                "  %d programmable alarms\n"
 246                                "  %d external time stamp channels\n"
 247                                "  %d programmable periodic signals\n"
 248                                "  %d pulse per second\n",
 249                                caps.max_adj,
 250                                caps.n_alarm,
 251                                caps.n_ext_ts,
 252                                caps.n_per_out,
 253                                caps.pps);
 254                 }
 255         }
 256
 257         if (0x7fffffff != adjfreq) {
 258                 memset(&tx, 0, sizeof(tx));
 259                 tx.modes = ADJ_FREQUENCY;
 260                 tx.freq = ppb_to_scaled_ppm(adjfreq);
 261                 if (clock_adjtime(clkid, &tx)) {
 262                         perror("clock_adjtime");
 263                 } else {
 264                         puts("frequency adjustment okay");
 265                 }
 266         }
 267
 268         if (adjtime) {
 269                 memset(&tx, 0, sizeof(tx));
 270                 tx.modes = ADJ_SETOFFSET;
 271                 tx.time.tv_sec = adjtime;
 272                 tx.time.tv_usec = 0;
 273                 if (clock_adjtime(clkid, &tx) < 0) {
 274                         perror("clock_adjtime");
 275                 } else {
 276                         puts("time shift okay");
 277                 }
 278         }
 279
 280         if (gettime) {
 281                 if (clock_gettime(clkid, &ts)) {
 282                         perror("clock_gettime");
 283                 } else {
 284                         printf("clock time: %ld.%09ld or %s",
 285                                ts.tv_sec, ts.tv_nsec, ctime(&ts.tv_sec));
 286                 }
 287         }
 288
 289         if (settime == 1) {
 290                 clock_gettime(CLOCK_REALTIME, &ts);
 291                 if (clock_settime(clkid, &ts)) {
 292                         perror("clock_settime");
 293                 } else {
 294                         puts("set time okay");
 295                 }
 296         }
 297
 298         if (settime == 2) {
 299                 clock_gettime(clkid, &ts);
 300                 if (clock_settime(CLOCK_REALTIME, &ts)) {
 301                         perror("clock_settime");
 302                 } else {
 303                         puts("set time okay");
 304                 }
 305         }
 306
 307         if (extts) {
 308                 memset(&extts_request, 0, sizeof(extts_request));
 309                 extts_request.index = index;
 310                 extts_request.flags = PTP_ENABLE_FEATURE;
 311                 if (ioctl(fd, PTP_EXTTS_REQUEST, &extts_request)) {
 312                         perror("PTP_EXTTS_REQUEST");
 313                         extts = 0;
 314                 } else {
 315                         puts("external time stamp request okay");
 316                 }
 317                 for (; extts; extts--) {
 318                         cnt = read(fd, &event, sizeof(event));
 319                         if (cnt != sizeof(event)) {
 320                                 perror("read");
 321                                 break;
 322                         }
 323                         printf("event index %u at %lld.%09u\n", event.index,
 324                                event.t.sec, event.t.nsec);
 325                         fflush(stdout);
 326                 }
 327                 /* Disable the feature again. */
 328                 extts_request.flags = 0;
 329                 if (ioctl(fd, PTP_EXTTS_REQUEST, &extts_request)) {
 330                         perror("PTP_EXTTS_REQUEST");
 331                 }
 332         }
 333
 334         if (oneshot) {
 335                 install_handler(SIGALRM, handle_alarm);
 336                 /* Create a timer. */
 337                 sigevent.sigev_notify = SIGEV_SIGNAL;
 338                 sigevent.sigev_signo = SIGALRM;
 339                 if (timer_create(clkid, &sigevent, &timerid)) {
 340                         perror("timer_create");
 341                         return -1;
 342                 }
 343                 /* Start the timer. */
 344                 memset(&timeout, 0, sizeof(timeout));
 345                 timeout.it_value.tv_sec = oneshot;
 346                 if (timer_settime(timerid, 0, &timeout, NULL)) {
 347                         perror("timer_settime");
 348                         return -1;
 349                 }
 350                 pause();
 351                 timer_delete(timerid);
 352         }
 353
 354         if (periodic) {
 355                 install_handler(SIGALRM, handle_alarm);
 356                 /* Create a timer. */
 357                 sigevent.sigev_notify = SIGEV_SIGNAL;
 358                 sigevent.sigev_signo = SIGALRM;
 359                 if (timer_create(clkid, &sigevent, &timerid)) {
 360                         perror("timer_create");
 361                         return -1;
 362                 }
 363                 /* Start the timer. */
 364                 memset(&timeout, 0, sizeof(timeout));
 365                 timeout.it_interval.tv_sec = periodic;
 366                 timeout.it_value.tv_sec = periodic;
 367                 if (timer_settime(timerid, 0, &timeout, NULL)) {
 368                         perror("timer_settime");
 369                         return -1;
 370                 }
 371                 while (1) {
 372                         pause();
 373                 }
 374                 timer_delete(timerid);
 375         }
 376
 377         if (perout >= 0) {
 378                 if (clock_gettime(clkid, &ts)) {
 379                         perror("clock_gettime");
 380                         return -1;
 381                 }
 382                 memset(&perout_request, 0, sizeof(perout_request));
 383                 perout_request.index = index;
 384                 perout_request.start.sec = ts.tv_sec + 2;
 385                 perout_request.start.nsec = 0;
 386                 perout_request.period.sec = 0;
 387                 perout_request.period.nsec = perout;
 388                 if (ioctl(fd, PTP_PEROUT_REQUEST, &perout_request)) {
 389                         perror("PTP_PEROUT_REQUEST");
 390                 } else {
 391                         puts("periodic output request okay");
 392                 }
 393         }
 394
 395         if (pps != -1) {
 396                 int enable = pps ? 1 : 0;
 397                 if (ioctl(fd, PTP_ENABLE_PPS, enable)) {
 398                         perror("PTP_ENABLE_PPS");
 399                 } else {
 400                         puts("pps for system time request okay");
 401                 }
 402         }
 403
 404         if (pct_offset) {
 405                 if (n_samples <= 0 || n_samples > 25) {
 406                         puts("n_samples should be between 1 and 25");
 407                         usage(progname);
 408                         return -1;
 409                 }
 410
 411                 sysoff = calloc(1, sizeof(*sysoff));
 412                 if (!sysoff) {
 413                         perror("calloc");
 414                         return -1;
 415                 }
 416                 sysoff->n_samples = n_samples;
 417
 418                 if (ioctl(fd, PTP_SYS_OFFSET, sysoff))
 419                         perror("PTP_SYS_OFFSET");
 420                 else
 421                         puts("system and phc clock time offset request okay");
 422
 423                 pct = &sysoff->ts[0];
 424                 for (i = 0; i < sysoff->n_samples; i++) {
 425                         t1 = pctns(pct+2*i);
 426                         tp = pctns(pct+2*i+1);
 427                         t2 = pctns(pct+2*i+2);
 428                         interval = t2 - t1;
 429                         offset = (t2 + t1) / 2 - tp;
 430
 431                         printf("system time: %ld.%ld\n",
 432                                 (pct+2*i)->sec, (pct+2*i)->nsec);
 433                         printf("phc    time: %ld.%ld\n",
 434                                 (pct+2*i+1)->sec, (pct+2*i+1)->nsec);
 435                         printf("system time: %ld.%ld\n",
 436                                 (pct+2*i+2)->sec, (pct+2*i+2)->nsec);
 437                         printf("system/phc clock time offset is %ld ns\n"
 438                                 "system     clock time delay  is %ld ns\n",
 439                                 offset, interval);
 440                 }
 441
 442                 free(sysoff);
 443         }
 444
 445         close(fd);
 446         return 0;
 447 }