linuxptp/phc2sys.c

797 lines
19 KiB
C

/**
* @file phc2sys.c
* @brief Utility program to synchronize two clocks via a PPS.
* @note Copyright (C) 2012 Richard Cochran <richardcochran@gmail.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <errno.h>
#include <fcntl.h>
#include <float.h>
#include <inttypes.h>
#include <limits.h>
#include <poll.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <linux/pps.h>
#include <linux/ptp_clock.h>
#include "clockadj.h"
#include "ds.h"
#include "fsm.h"
#include "missing.h"
#include "phc.h"
#include "pi.h"
#include "pmc_common.h"
#include "print.h"
#include "servo.h"
#include "sk.h"
#include "stats.h"
#include "sysoff.h"
#include "tlv.h"
#include "util.h"
#include "version.h"
#define KP 0.7
#define KI 0.3
#define NS_PER_SEC 1000000000LL
#define PHC_PPS_OFFSET_LIMIT 10000000
#define PMC_UPDATE_INTERVAL (60 * NS_PER_SEC)
struct clock;
static int update_sync_offset(struct clock *clock, int64_t offset, uint64_t ts);
static clockid_t clock_open(char *device)
{
struct sk_ts_info ts_info;
char phc_device[16];
int clkid;
/* check if device is CLOCK_REALTIME */
if (!strcasecmp(device, "CLOCK_REALTIME"))
return CLOCK_REALTIME;
/* check if device is valid phc device */
clkid = phc_open(device);
if (clkid != CLOCK_INVALID)
return clkid;
/* check if device is a valid ethernet device */
if (sk_get_ts_info(device, &ts_info) || !ts_info.valid) {
fprintf(stderr, "unknown clock %s: %m\n", device);
return CLOCK_INVALID;
}
if (ts_info.phc_index < 0) {
fprintf(stderr, "interface %s does not have a PHC\n", device);
return CLOCK_INVALID;
}
sprintf(phc_device, "/dev/ptp%d", ts_info.phc_index);
clkid = phc_open(phc_device);
if (clkid == CLOCK_INVALID)
fprintf(stderr, "cannot open %s: %m\n", device);
return clkid;
}
static int read_phc(clockid_t clkid, clockid_t sysclk, int readings,
int64_t *offset, uint64_t *ts, int64_t *delay)
{
struct timespec tdst1, tdst2, tsrc;
int i;
int64_t interval, best_interval = INT64_MAX;
/* Pick the quickest clkid reading. */
for (i = 0; i < readings; i++) {
if (clock_gettime(sysclk, &tdst1) ||
clock_gettime(clkid, &tsrc) ||
clock_gettime(sysclk, &tdst2)) {
pr_err("failed to read clock: %m");
return 0;
}
interval = (tdst2.tv_sec - tdst1.tv_sec) * NS_PER_SEC +
tdst2.tv_nsec - tdst1.tv_nsec;
if (best_interval > interval) {
best_interval = interval;
*offset = (tdst1.tv_sec - tsrc.tv_sec) * NS_PER_SEC +
tdst1.tv_nsec - tsrc.tv_nsec + interval / 2;
*ts = tdst2.tv_sec * NS_PER_SEC + tdst2.tv_nsec;
}
}
*delay = best_interval;
return 1;
}
struct clock {
clockid_t clkid;
struct servo *servo;
enum servo_state servo_state;
const char *source_label;
struct stats *offset_stats;
struct stats *freq_stats;
struct stats *delay_stats;
unsigned int stats_max_count;
int sync_offset;
int sync_offset_direction;
int leap;
int leap_set;
int kernel_leap;
struct pmc *pmc;
int pmc_ds_idx;
int pmc_ds_requested;
uint64_t pmc_last_update;
};
static void update_clock_stats(struct clock *clock,
int64_t offset, double freq, int64_t delay)
{
struct stats_result offset_stats, freq_stats, delay_stats;
stats_add_value(clock->offset_stats, offset);
stats_add_value(clock->freq_stats, freq);
if (delay >= 0)
stats_add_value(clock->delay_stats, delay);
if (stats_get_num_values(clock->offset_stats) < clock->stats_max_count)
return;
stats_get_result(clock->offset_stats, &offset_stats);
stats_get_result(clock->freq_stats, &freq_stats);
if (!stats_get_result(clock->delay_stats, &delay_stats)) {
pr_info("rms %4.0f max %4.0f "
"freq %+6.0f +/- %3.0f "
"delay %5.0f +/- %3.0f",
offset_stats.rms, offset_stats.max_abs,
freq_stats.mean, freq_stats.stddev,
delay_stats.mean, delay_stats.stddev);
} else {
pr_info("rms %4.0f max %4.0f "
"freq %+6.0f +/- %3.0f",
offset_stats.rms, offset_stats.max_abs,
freq_stats.mean, freq_stats.stddev);
}
stats_reset(clock->offset_stats);
stats_reset(clock->freq_stats);
stats_reset(clock->delay_stats);
}
static void update_clock(struct clock *clock,
int64_t offset, uint64_t ts, int64_t delay)
{
enum servo_state state;
double ppb;
if (update_sync_offset(clock, offset, ts))
return;
if (clock->sync_offset_direction)
offset += clock->sync_offset * NS_PER_SEC *
clock->sync_offset_direction;
ppb = servo_sample(clock->servo, offset, ts, &state);
clock->servo_state = state;
switch (state) {
case SERVO_UNLOCKED:
break;
case SERVO_JUMP:
clockadj_step(clock->clkid, -offset);
/* Fall through. */
case SERVO_LOCKED:
clockadj_set_freq(clock->clkid, -ppb);
if (clock->clkid == CLOCK_REALTIME)
sysclk_set_sync();
break;
}
if (clock->offset_stats) {
update_clock_stats(clock, offset, ppb, delay);
} else {
if (delay >= 0) {
pr_info("%s offset %9" PRId64 " s%d freq %+7.0f "
"delay %6" PRId64,
clock->source_label, offset, state, ppb, delay);
} else {
pr_info("%s offset %9" PRId64 " s%d freq %+7.0f",
clock->source_label, offset, state, ppb);
}
}
}
static void enable_pps_output(clockid_t src)
{
int enable = 1;
if (!phc_has_pps(src))
return;
if (ioctl(CLOCKID_TO_FD(src), PTP_ENABLE_PPS, enable) < 0)
pr_warning("failed to enable PPS output");
}
static int read_pps(int fd, int64_t *offset, uint64_t *ts)
{
struct pps_fdata pfd;
pfd.timeout.sec = 10;
pfd.timeout.nsec = 0;
pfd.timeout.flags = ~PPS_TIME_INVALID;
if (ioctl(fd, PPS_FETCH, &pfd)) {
pr_err("failed to fetch PPS: %m");
return 0;
}
*ts = pfd.info.assert_tu.sec * NS_PER_SEC;
*ts += pfd.info.assert_tu.nsec;
*offset = *ts % NS_PER_SEC;
if (*offset > NS_PER_SEC / 2)
*offset -= NS_PER_SEC;
return 1;
}
static int do_pps_loop(struct clock *clock, int fd,
clockid_t src, int n_readings)
{
int64_t pps_offset, phc_offset, phc_delay;
uint64_t pps_ts, phc_ts;
clock->source_label = "pps";
if (src == CLOCK_INVALID) {
/* The sync offset can't be applied with PPS alone. */
clock->sync_offset_direction = 0;
} else {
enable_pps_output(src);
}
while (1) {
if (!read_pps(fd, &pps_offset, &pps_ts)) {
continue;
}
/* If a PHC is available, use it to get the whole number
of seconds in the offset and PPS for the rest. */
if (src != CLOCK_INVALID) {
if (!read_phc(src, clock->clkid, n_readings,
&phc_offset, &phc_ts, &phc_delay))
return -1;
/* Convert the time stamp to the PHC time. */
phc_ts -= phc_offset;
/* Check if it is close to the start of the second. */
if (phc_ts % NS_PER_SEC > PHC_PPS_OFFSET_LIMIT) {
pr_warning("PPS is not in sync with PHC"
" (0.%09lld)", phc_ts % NS_PER_SEC);
continue;
}
phc_ts = phc_ts / NS_PER_SEC * NS_PER_SEC;
pps_offset = pps_ts - phc_ts;
}
update_clock(clock, pps_offset, pps_ts, -1);
}
close(fd);
return 0;
}
static int do_sysoff_loop(struct clock *clock, clockid_t src,
struct timespec *interval, int n_readings)
{
uint64_t ts;
int64_t offset, delay;
int err = 0, fd = CLOCKID_TO_FD(src);
clock->source_label = "sys";
while (1) {
clock_nanosleep(CLOCK_MONOTONIC, 0, interval, NULL);
if (sysoff_measure(fd, n_readings, &offset, &ts, &delay)) {
err = -1;
break;
}
update_clock(clock, offset, ts, delay);
}
return err;
}
static int do_phc_loop(struct clock *clock, clockid_t src,
struct timespec *interval, int n_readings)
{
uint64_t ts;
int64_t offset, delay;
clock->source_label = "phc";
while (1) {
clock_nanosleep(CLOCK_MONOTONIC, 0, interval, NULL);
if (!read_phc(src, clock->clkid, n_readings,
&offset, &ts, &delay)) {
continue;
}
update_clock(clock, offset, ts, delay);
}
return 0;
}
static int is_msg_mgt(struct ptp_message *msg)
{
struct TLV *tlv;
if (msg_type(msg) != MANAGEMENT)
return 0;
if (management_action(msg) != RESPONSE)
return 0;
if (msg->tlv_count != 1)
return 0;
tlv = (struct TLV *) msg->management.suffix;
if (tlv->type != TLV_MANAGEMENT)
return 0;
return 1;
}
static int get_mgt_id(struct ptp_message *msg)
{
struct management_tlv *mgt = (struct management_tlv *) msg->management.suffix;
return mgt->id;
}
static void *get_mgt_data(struct ptp_message *msg)
{
struct management_tlv *mgt = (struct management_tlv *) msg->management.suffix;
return mgt->data;
}
static int init_pmc(struct clock *clock, int domain_number)
{
clock->pmc = pmc_create(TRANS_UDS, "/var/run/phc2sys", 0,
domain_number, 0);
if (!clock->pmc) {
pr_err("failed to create pmc");
return -1;
}
return 0;
}
static int run_pmc(struct clock *clock, int timeout,
int wait_sync, int get_utc_offset)
{
struct ptp_message *msg;
struct timePropertiesDS *tds;
void *data;
#define N_FD 1
struct pollfd pollfd[N_FD];
int cnt, ds_done;
#define N_ID 2
int ds_ids[N_ID] = {
PORT_DATA_SET,
TIME_PROPERTIES_DATA_SET
};
while (clock->pmc_ds_idx < N_ID) {
/* Check if the data set is really needed. */
if ((ds_ids[clock->pmc_ds_idx] == PORT_DATA_SET &&
!wait_sync) ||
(ds_ids[clock->pmc_ds_idx] == TIME_PROPERTIES_DATA_SET &&
!get_utc_offset)) {
clock->pmc_ds_idx++;
continue;
}
pollfd[0].fd = pmc_get_transport_fd(clock->pmc);
pollfd[0].events = POLLIN|POLLPRI;
if (!clock->pmc_ds_requested)
pollfd[0].events |= POLLOUT;
cnt = poll(pollfd, N_FD, timeout);
if (cnt < 0) {
pr_err("poll failed");
return -1;
}
if (!cnt) {
/* Request the data set again in the next run. */
clock->pmc_ds_requested = 0;
return 0;
}
/* Send a new request if there are no pending messages. */
if ((pollfd[0].revents & POLLOUT) &&
!(pollfd[0].revents & (POLLIN|POLLPRI))) {
pmc_send_get_action(clock->pmc,
ds_ids[clock->pmc_ds_idx]);
clock->pmc_ds_requested = 1;
}
if (!(pollfd[0].revents & (POLLIN|POLLPRI)))
continue;
msg = pmc_recv(clock->pmc);
if (!msg)
continue;
if (!is_msg_mgt(msg) ||
get_mgt_id(msg) != ds_ids[clock->pmc_ds_idx]) {
msg_put(msg);
continue;
}
data = get_mgt_data(msg);
ds_done = 0;
switch (get_mgt_id(msg)) {
case PORT_DATA_SET:
switch (((struct portDS *)data)->portState) {
case PS_MASTER:
case PS_SLAVE:
ds_done = 1;
break;
}
break;
case TIME_PROPERTIES_DATA_SET:
tds = (struct timePropertiesDS *)data;
if (tds->flags & PTP_TIMESCALE) {
clock->sync_offset = tds->currentUtcOffset;
if (tds->flags & LEAP_61)
clock->leap = 1;
else if (tds->flags & LEAP_59)
clock->leap = -1;
else
clock->leap = 0;
}
ds_done = 1;
break;
}
if (ds_done) {
/* Proceed with the next data set. */
clock->pmc_ds_idx++;
clock->pmc_ds_requested = 0;
}
msg_put(msg);
}
clock->pmc_ds_idx = 0;
return 1;
}
static void close_pmc(struct clock *clock)
{
pmc_destroy(clock->pmc);
clock->pmc = NULL;
}
static int update_sync_offset(struct clock *clock, int64_t offset, uint64_t ts)
{
int clock_leap;
if (clock->pmc &&
!(ts > clock->pmc_last_update &&
ts - clock->pmc_last_update < PMC_UPDATE_INTERVAL)) {
if (run_pmc(clock, 0, 0, 1) > 0)
clock->pmc_last_update = ts;
}
/* Handle leap seconds. */
if (!clock->leap && !clock->leap_set)
return 0;
/* If the system clock is the master clock, get a time stamp from
it, as it is the clock which will include the leap second. */
if (clock->clkid != CLOCK_REALTIME) {
struct timespec tp;
if (clock_gettime(CLOCK_REALTIME, &tp)) {
pr_err("failed to read clock: %m");
return -1;
}
ts = tp.tv_sec * NS_PER_SEC + tp.tv_nsec;
}
/* If the clock will be stepped, the time stamp has to be the
target time. Ignore possible 1 second error in UTC offset. */
if (clock->clkid == CLOCK_REALTIME &&
clock->servo_state == SERVO_UNLOCKED) {
ts -= offset + clock->sync_offset * NS_PER_SEC *
clock->sync_offset_direction;
}
/* Suspend clock updates in the last second before midnight. */
if (is_utc_ambiguous(ts)) {
pr_info("clock update suspended due to leap second");
return -1;
}
clock_leap = leap_second_status(ts, clock->leap_set,
&clock->leap, &clock->sync_offset);
if (clock->leap_set != clock_leap) {
/* Only the system clock can leap. */
if (clock->clkid == CLOCK_REALTIME && clock->kernel_leap)
sysclk_set_leap(clock_leap);
clock->leap_set = clock_leap;
}
return 0;
}
static void usage(char *progname)
{
fprintf(stderr,
"\n"
"usage: %s [options]\n\n"
" -c [dev|name] slave clock (CLOCK_REALTIME)\n"
" -d [dev] master PPS device\n"
" -s [dev|name] master clock\n"
" -P [kp] proportional constant (0.7)\n"
" -I [ki] integration constant (0.3)\n"
" -S [step] step threshold (disabled)\n"
" -R [rate] slave clock update rate in HZ (1.0)\n"
" -N [num] number of master clock readings per update (5)\n"
" -O [offset] slave-master time offset (0)\n"
" -u [num] number of clock updates in summary stats (0)\n"
" -w wait for ptp4l\n"
" -n [num] domain number (0)\n"
" -x apply leap seconds by servo instead of kernel\n"
" -l [num] set the logging level to 'num' (6)\n"
" -m print messages to stdout\n"
" -q do not print messages to the syslog\n"
" -v prints the software version and exits\n"
" -h prints this message and exits\n"
"\n",
progname);
}
int main(int argc, char *argv[])
{
char *progname;
clockid_t src = CLOCK_INVALID;
int c, domain_number = 0, phc_readings = 5, pps_fd = -1;
int max_ppb, r, wait_sync = 0, forced_sync_offset = 0;
int print_level = LOG_INFO, use_syslog = 1, verbose = 0;
double ppb, phc_interval = 1.0, phc_rate;
struct timespec phc_interval_tp;
struct clock dst_clock = {
.clkid = CLOCK_REALTIME,
.servo_state = SERVO_UNLOCKED,
.kernel_leap = 1,
};
configured_pi_kp = KP;
configured_pi_ki = KI;
/* Process the command line arguments. */
progname = strrchr(argv[0], '/');
progname = progname ? 1+progname : argv[0];
while (EOF != (c = getopt(argc, argv,
"c:d:hs:P:I:S:R:N:O:i:u:wn:xl:mqv"))) {
switch (c) {
case 'c':
dst_clock.clkid = clock_open(optarg);
break;
case 'd':
pps_fd = open(optarg, O_RDONLY);
if (pps_fd < 0) {
fprintf(stderr,
"cannot open '%s': %m\n", optarg);
return -1;
}
break;
case 'i':
fprintf(stderr,
"'-i' has been deprecated. please use '-s' instead.\n");
case 's':
src = clock_open(optarg);
break;
case 'P':
if (get_arg_val_d(c, optarg, &configured_pi_kp,
0.0, DBL_MAX))
return -1;
break;
case 'I':
if (get_arg_val_d(c, optarg, &configured_pi_ki,
0.0, DBL_MAX))
return -1;
break;
case 'S':
if (get_arg_val_d(c, optarg, &configured_pi_offset,
0.0, DBL_MAX))
return -1;
break;
case 'R':
if (get_arg_val_d(c, optarg, &phc_rate, 0.0, DBL_MAX))
return -1;
phc_interval = 1.0 / phc_rate;
/* phc_interval will be assigned to a time_t variable. */
/* check if that occurs overflow. */
if ((sizeof(time_t) == 8 && phc_interval > INT64_MAX) ||
(sizeof(time_t) == 4 && phc_interval > INT32_MAX)) {
fprintf(stderr,
"-R: %s is too small\n", optarg);
return -1;
}
break;
case 'N':
if (get_arg_val_i(c, optarg, &phc_readings, 1, INT_MAX))
return -1;
break;
case 'O':
if (get_arg_val_i(c, optarg, &dst_clock.sync_offset,
INT_MIN, INT_MAX))
return -1;
dst_clock.sync_offset_direction = -1;
forced_sync_offset = 1;
break;
case 'u':
if (get_arg_val_ui(c, optarg, &dst_clock.stats_max_count,
0, UINT_MAX))
return -1;
break;
case 'w':
wait_sync = 1;
break;
case 'n':
if (get_arg_val_i(c, optarg, &domain_number, 0, 255))
return -1;
break;
case 'x':
dst_clock.kernel_leap = 0;
break;
case 'l':
if (get_arg_val_i(c, optarg, &print_level,
PRINT_LEVEL_MIN, PRINT_LEVEL_MAX))
return -1;
break;
case 'm':
verbose = 1;
break;
case 'q':
use_syslog = 0;
break;
case 'v':
version_show(stdout);
return 0;
case 'h':
usage(progname);
return 0;
default:
usage(progname);
return -1;
}
}
if (pps_fd < 0 && src == CLOCK_INVALID) {
fprintf(stderr,
"valid source clock must be selected.\n");
usage(progname);
return -1;
}
if (dst_clock.clkid == CLOCK_INVALID) {
fprintf(stderr,
"valid destination clock must be selected.\n");
usage(progname);
return -1;
}
if (pps_fd >= 0 && dst_clock.clkid != CLOCK_REALTIME) {
fprintf(stderr,
"cannot use a pps device unless destination is CLOCK_REALTIME\n");
usage(progname);
return -1;
}
if (!wait_sync && !forced_sync_offset) {
fprintf(stderr,
"time offset must be specified using -w or -O\n");
usage(progname);
return -1;
}
if (dst_clock.stats_max_count > 0) {
dst_clock.offset_stats = stats_create();
dst_clock.freq_stats = stats_create();
dst_clock.delay_stats = stats_create();
if (!dst_clock.offset_stats ||
!dst_clock.freq_stats ||
!dst_clock.delay_stats) {
fprintf(stderr, "failed to create stats");
return -1;
}
}
print_set_progname(progname);
print_set_verbose(verbose);
print_set_syslog(use_syslog);
print_set_level(print_level);
if (wait_sync) {
if (init_pmc(&dst_clock, domain_number))
return -1;
while (1) {
r = run_pmc(&dst_clock, 1000,
wait_sync, !forced_sync_offset);
if (r < 0)
return -1;
else if (r > 0)
break;
else
pr_notice("Waiting for ptp4l...");
}
if (!forced_sync_offset) {
if (src != CLOCK_REALTIME &&
dst_clock.clkid == CLOCK_REALTIME)
dst_clock.sync_offset_direction = 1;
else if (src == CLOCK_REALTIME &&
dst_clock.clkid != CLOCK_REALTIME)
dst_clock.sync_offset_direction = -1;
else
dst_clock.sync_offset_direction = 0;
}
if (forced_sync_offset || !dst_clock.sync_offset_direction)
close_pmc(&dst_clock);
}
ppb = clockadj_get_freq(dst_clock.clkid);
/* The reading may silently fail and return 0, reset the frequency to
make sure ppb is the actual frequency of the clock. */
clockadj_set_freq(dst_clock.clkid, ppb);
if (dst_clock.clkid == CLOCK_REALTIME) {
sysclk_set_leap(0);
max_ppb = sysclk_max_freq();
} else {
max_ppb = phc_max_adj(dst_clock.clkid);
if (!max_ppb) {
pr_err("clock is not adjustable");
return -1;
}
}
dst_clock.servo = servo_create(CLOCK_SERVO_PI, -ppb, max_ppb, 0);
if (pps_fd >= 0)
return do_pps_loop(&dst_clock, pps_fd, src, phc_readings);
phc_interval_tp.tv_sec = phc_interval;
phc_interval_tp.tv_nsec = (phc_interval - phc_interval_tp.tv_sec) * 1e9;
if (dst_clock.clkid == CLOCK_REALTIME && src != CLOCK_REALTIME &&
SYSOFF_SUPPORTED == sysoff_probe(CLOCKID_TO_FD(src), phc_readings))
return do_sysoff_loop(&dst_clock, src, &phc_interval_tp,
phc_readings);
return do_phc_loop(&dst_clock, src, &phc_interval_tp, phc_readings);
}