/** * @file clock.c * @note Copyright (C) 2011 Richard Cochran * * 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 #include #include #include #include #include "bmc.h" #include "clock.h" #include "foreign.h" #include "mave.h" #include "missing.h" #include "msg.h" #include "phc.h" #include "port.h" #include "servo.h" #include "print.h" #include "tlv.h" #include "uds.h" #include "util.h" #define CLK_N_PORTS (MAX_PORTS + 1) /* plus one for the UDS interface */ #define FAULT_RESET_SECONDS 15 #define N_CLOCK_PFD (N_POLLFD + 1) /* one extra per port, for the fault timer */ #define MAVE_LENGTH 10 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) struct freq_estimator { tmv_t origin1; tmv_t ingress1; int max_count; int count; }; struct clock { clockid_t clkid; struct servo *servo; struct defaultDS dds; struct dataset default_dataset; struct currentDS cur; struct parentDS dad; struct timePropertiesDS tds; struct ClockIdentity ptl[PATH_TRACE_MAX]; struct foreign_clock *best; struct port *port[CLK_N_PORTS]; struct pollfd pollfd[CLK_N_PORTS*N_CLOCK_PFD]; int fault_fd[CLK_N_PORTS]; time_t fault_timeout; int nports; /* does not include the UDS port */ tmv_t master_offset; tmv_t path_delay; struct mave *avg_delay; struct freq_estimator fest; tmv_t c1; tmv_t c2; tmv_t t1; tmv_t t2; }; struct clock the_clock; static void handle_state_decision_event(struct clock *c); static int cid_eq(struct ClockIdentity *a, struct ClockIdentity *b) { return 0 == memcmp(a, b, sizeof(*a)); } static void clock_destroy(struct clock *c) { int i; for (i = 0; i < c->nports; i++) { port_close(c->port[i]); close(c->fault_fd[i]); } port_close(c->port[i]); /*uds*/ if (c->clkid != CLOCK_REALTIME) { phc_close(c->clkid); } servo_destroy(c->servo); mave_destroy(c->avg_delay); memset(c, 0, sizeof(*c)); } static int clock_fault_timeout(struct clock *c, int index, int set) { struct itimerspec tmo = { {0, 0}, {0, 0} }; if (set) { pr_debug("waiting %d seconds to clear fault on port %d", c->fault_timeout, index); tmo.it_value.tv_sec = c->fault_timeout; } else { pr_debug("clearing fault on port %d", index); } return timerfd_settime(c->fault_fd[index], 0, &tmo, NULL); } static int clock_management_response(struct clock *c, struct port *p, int id, struct ptp_message *req) { int datalen = 0, err, pdulen, respond = 0; struct management_tlv *tlv; struct ptp_message *rsp; struct PortIdentity pid = port_identity(p); rsp = port_management_reply(pid, p, req); if (!rsp) { return 0; } tlv = (struct management_tlv *) rsp->management.suffix; tlv->type = TLV_MANAGEMENT; tlv->id = id; switch (id) { case CURRENT_DATA_SET: memcpy(tlv->data, &c->cur, sizeof(c->cur)); datalen = sizeof(c->cur); respond = 1; break; } if (respond) { tlv->length = sizeof(tlv->id) + datalen; pdulen = rsp->header.messageLength + sizeof(*tlv) + datalen; rsp->header.messageLength = pdulen; rsp->tlv_count = 1; err = msg_pre_send(rsp); if (err) { goto out; } err = port_forward(p, rsp, pdulen); } out: msg_put(rsp); return respond ? 1 : 0; } static int clock_master_lost(struct clock *c) { int i; for (i = 0; i < c->nports; i++) { if (PS_SLAVE == port_state(c->port[i])) return 0; } return 1; } static enum servo_state clock_no_adjust(struct clock *c) { double ratio; struct freq_estimator *f = &c->fest; enum servo_state state = SERVO_UNLOCKED; /* * We have clock.t1 as the origin time stamp, and clock.t2 as * the ingress. The time at which the master sent the sync is: * * origin = origin_ts + path_delay + correction * * The ratio of the local clock freqency to the master clock * is estimated by: * * (ingress_2 - ingress_1) / (origin_2 - origin_1) * * Both of the origin time estimates include the path delay, * but we assume that the path delay is in fact constant. * By leaving out the path delay altogther, we can avoid the * error caused by our imperfect path delay measurement. */ f->count++; if (f->count < f->max_count) { return state; } if (f->ingress1) { ratio = (c->t2 - f->ingress1 + 0.0) / (c->t1 /*+c->path_delay*/ + c->c1 + c->c2 - f->origin1); pr_info("master offset %10lld s%d ratio %.9f path delay %10lld", c->master_offset, state, ratio, c->path_delay); } f->ingress1 = c->t2; f->origin1 = c->t1 /*+c->path_delay*/ + c->c1 + c->c2; f->count = 0; return state; } static void clock_ppb(clockid_t clkid, double ppb) { struct timex tx; memset(&tx, 0, sizeof(tx)); tx.modes = ADJ_FREQUENCY; tx.freq = (long) (ppb * 65.536); if (clock_adjtime(clkid, &tx) < 0) pr_err("failed to adjust the clock: %m"); } static void clock_step(clockid_t clkid, int64_t ns) { struct timex tx; int sign = 1; if (ns < 0) { sign = -1; ns *= -1; } memset(&tx, 0, sizeof(tx)); tx.modes = ADJ_SETOFFSET | ADJ_NANO; tx.time.tv_sec = sign * (ns / NS_PER_SEC); tx.time.tv_usec = sign * (ns % NS_PER_SEC); /* * The value of a timeval is the sum of its fields, but the * field tv_usec must always be non-negative. */ if (tx.time.tv_usec < 0) { tx.time.tv_sec -= 1; tx.time.tv_usec += 1000000000; } if (clock_adjtime(clkid, &tx) < 0) pr_err("failed to step clock: %m"); } static void clock_update_grandmaster(struct clock *c) { memset(&c->cur, 0, sizeof(c->cur)); memset(c->ptl, 0, sizeof(c->ptl)); c->dad.parentPortIdentity.clockIdentity = c->dds.clockIdentity; c->dad.parentPortIdentity.portNumber = 0; c->dad.grandmasterIdentity = c->dds.clockIdentity; c->dad.grandmasterClockQuality = c->dds.clockQuality; c->dad.grandmasterPriority1 = c->dds.priority1; c->dad.grandmasterPriority2 = c->dds.priority2; c->dad.path_length = 0; c->tds.currentUtcOffset = CURRENT_UTC_OFFSET; c->tds.currentUtcOffsetValid = FALSE; c->tds.leap61 = FALSE; c->tds.leap59 = FALSE; c->tds.timeTraceable = FALSE; c->tds.frequencyTraceable = FALSE; c->tds.ptpTimescale = TRUE; c->tds.timeSource = INTERNAL_OSCILLATOR; } static void clock_update_slave(struct clock *c) { struct ptp_message *msg = TAILQ_FIRST(&c->best->messages); c->cur.stepsRemoved = 1 + c->best->dataset.stepsRemoved; c->dad.parentPortIdentity = c->best->dataset.sender; c->dad.grandmasterIdentity = msg->announce.grandmasterIdentity; c->dad.grandmasterClockQuality = msg->announce.grandmasterClockQuality; c->dad.grandmasterPriority1 = msg->announce.grandmasterPriority1; c->dad.grandmasterPriority2 = msg->announce.grandmasterPriority2; c->tds.currentUtcOffset = msg->announce.currentUtcOffset; c->tds.currentUtcOffsetValid = field_is_set(msg, 1, UTC_OFF_VALID); c->tds.leap61 = field_is_set(msg, 1, LEAP_61); c->tds.leap59 = field_is_set(msg, 1, LEAP_59); c->tds.timeTraceable = field_is_set(msg, 1, TIME_TRACEABLE); c->tds.frequencyTraceable = field_is_set(msg, 1, FREQ_TRACEABLE); c->tds.ptpTimescale = field_is_set(msg, 1, PTP_TIMESCALE); c->tds.timeSource = msg->announce.timeSource; if (!c->tds.ptpTimescale) { pr_warning("foreign master not using PTP timescale"); } if (c->tds.currentUtcOffset < CURRENT_UTC_OFFSET) { pr_warning("running in a temporal vortex"); } } static int forwarding(struct clock *c, struct port *p) { enum port_state ps = port_state(p); switch (ps) { case PS_MASTER: case PS_GRAND_MASTER: case PS_SLAVE: case PS_UNCALIBRATED: case PS_PRE_MASTER: return 1; default: break; } if (p == c->port[c->nports]) { /*uds*/ return 1; } return 0; } /* public methods */ UInteger8 clock_class(struct clock *c) { return c->dds.clockQuality.clockClass; } struct clock *clock_create(int phc_index, struct interface *iface, int count, enum timestamp_type timestamping, struct defaultDS *ds) { int i, max_adj, sw_ts = timestamping == TS_SOFTWARE ? 1 : 0; struct clock *c = &the_clock; char phc[32]; struct interface udsif; memset(&udsif, 0, sizeof(udsif)); snprintf(udsif.name, sizeof(udsif.name), UDS_PATH); udsif.transport = TRANS_UDS; srandom(time(NULL)); if (c->nports) clock_destroy(c); if (phc_index >= 0) { snprintf(phc, 31, "/dev/ptp%d", phc_index); c->clkid = phc_open(phc); if (c->clkid == CLOCK_INVALID) { pr_err("Failed to open %s: %m", phc); return NULL; } max_adj = phc_max_adj(c->clkid); if (!max_adj) { pr_err("clock is not adjustable"); return NULL; } } else { c->clkid = CLOCK_REALTIME; max_adj = 512000; } c->servo = servo_create("pi", max_adj, sw_ts); if (!c->servo) { pr_err("Failed to create clock servo"); return NULL; } c->avg_delay = mave_create(MAVE_LENGTH); if (!c->avg_delay) { pr_err("Failed to create moving average"); return NULL; } c->dds = *ds; /* Initialize the parentDS. */ clock_update_grandmaster(c); c->dad.parentStats = 0; c->dad.observedParentOffsetScaledLogVariance = 0xffff; c->dad.observedParentClockPhaseChangeRate = 0x7fffffff; c->dad.ptl = c->ptl; for (i = 0; i < ARRAY_SIZE(c->pollfd); i++) { c->pollfd[i].fd = -1; c->pollfd[i].events = 0; } c->fault_timeout = FAULT_RESET_SECONDS; c->fest.max_count = 2; for (i = 0; i < count; i++) { c->port[i] = port_open(phc_index, timestamping, 1+i, &iface[i], c); if (!c->port[i]) { pr_err("failed to open port %s", iface[i].name); return NULL; } c->fault_fd[i] = timerfd_create(CLOCK_MONOTONIC, 0); if (c->fault_fd[i] < 0) { pr_err("timerfd_create failed: %m"); return NULL; } c->pollfd[N_CLOCK_PFD * i + N_POLLFD].fd = c->fault_fd[i]; c->pollfd[N_CLOCK_PFD * i + N_POLLFD].events = POLLIN|POLLPRI; } /* * One extra port is for the UDS interface. */ c->port[i] = port_open(phc_index, timestamping, 0, &udsif, c); if (!c->port[i]) { pr_err("failed to open the UDS port"); return NULL; } c->dds.numberPorts = c->nports = count; for (i = 0; i < c->nports; i++) port_dispatch(c->port[i], EV_INITIALIZE, 0); port_dispatch(c->port[i], EV_INITIALIZE, 0); /*uds*/ return c; } struct dataset *clock_best_foreign(struct clock *c) { return c->best ? &c->best->dataset : NULL; } struct port *clock_best_port(struct clock *c) { return c->best ? c->best->port : NULL; } struct dataset *clock_default_ds(struct clock *c) { struct dataset *out = &c->default_dataset; struct defaultDS *in = &c->dds; out->priority1 = in->priority1; out->identity = in->clockIdentity; out->quality = in->clockQuality; out->priority2 = in->priority2; out->stepsRemoved = 0; out->sender.clockIdentity = in->clockIdentity; out->sender.portNumber = 0; out->receiver.clockIdentity = in->clockIdentity; out->receiver.portNumber = 0; return out; } UInteger8 clock_domain_number(struct clock *c) { return c->dds.domainNumber; } struct ClockIdentity clock_identity(struct clock *c) { return c->dds.clockIdentity; } void clock_install_fda(struct clock *c, struct port *p, struct fdarray fda) { int i, j, k; for (i = 0; i < c->nports + 1; i++) { if (p == c->port[i]) break; } for (j = 0; j < N_POLLFD; j++) { k = N_CLOCK_PFD * i + j; c->pollfd[k].fd = fda.fd[j]; c->pollfd[k].events = POLLIN|POLLPRI; } } void clock_manage(struct clock *c, struct port *p, struct ptp_message *msg) { int i, pdulen; struct port *fwd; struct management_tlv *mgt; struct PortIdentity pid; struct ClockIdentity *tcid, wildcard = { {0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff} }; /* Forward this message out all eligible ports. */ if (forwarding(c, p) && msg->management.boundaryHops) { pdulen = msg->header.messageLength; msg->management.boundaryHops--; msg_pre_send(msg); for (i = 0; i < c->nports + 1; i++) { fwd = c->port[i]; if (fwd != p && forwarding(c, fwd) && port_forward(fwd, msg, pdulen)) pr_err("port %d: management forward failed", i); } msg_post_recv(msg, pdulen); msg->management.boundaryHops++; } /* Apply this message to the local clock and ports. */ tcid = &msg->management.targetPortIdentity.clockIdentity; if (!cid_eq(tcid, &wildcard) && !cid_eq(tcid, &c->dds.clockIdentity)) { return; } if (msg->tlv_count != 1) { return; } mgt = (struct management_tlv *) msg->management.suffix; if (clock_management_response(c, p, mgt->id, msg)) return; switch (mgt->id) { case USER_DESCRIPTION: case SAVE_IN_NON_VOLATILE_STORAGE: case RESET_NON_VOLATILE_STORAGE: case INITIALIZE: case FAULT_LOG: case FAULT_LOG_RESET: case DEFAULT_DATA_SET: case PARENT_DATA_SET: case TIME_PROPERTIES_DATA_SET: case PRIORITY1: case PRIORITY2: case DOMAIN: case SLAVE_ONLY: case TIME: case CLOCK_ACCURACY: case UTC_PROPERTIES: case TRACEABILITY_PROPERTIES: case TIMESCALE_PROPERTIES: case PATH_TRACE_LIST: case PATH_TRACE_ENABLE: case GRANDMASTER_CLUSTER_TABLE: case ACCEPTABLE_MASTER_TABLE: case ACCEPTABLE_MASTER_MAX_TABLE_SIZE: case ALTERNATE_TIME_OFFSET_ENABLE: case ALTERNATE_TIME_OFFSET_NAME: case ALTERNATE_TIME_OFFSET_MAX_KEY: case ALTERNATE_TIME_OFFSET_PROPERTIES: case TRANSPARENT_CLOCK_DEFAULT_DATA_SET: case PRIMARY_DOMAIN: pid = port_identity(p); if (port_managment_error(pid, p, msg, NOT_SUPPORTED)) pr_err("failed to send management error status"); break; default: for (i = 0; i < c->nports; i++) { if (port_manage(c->port[i], p, msg)) break; } break; } } struct parentDS *clock_parent_ds(struct clock *c) { return &c->dad; } struct PortIdentity clock_parent_identity(struct clock *c) { return c->dad.parentPortIdentity; } int clock_poll(struct clock *c) { int cnt, i, j, k, lost = 0, sde = 0; enum fsm_event event; cnt = poll(c->pollfd, ARRAY_SIZE(c->pollfd), -1); if (cnt < 0) { if (EINTR == errno) { return 0; } else { pr_emerg("poll failed"); return -1; } } else if (!cnt) { return 0; } for (i = 0; i < c->nports; i++) { /* Let the ports handle their events. */ for (j = 0; j < N_POLLFD; j++) { k = N_CLOCK_PFD * i + j; if (c->pollfd[k].revents & (POLLIN|POLLPRI)) { event = port_event(c->port[i], j); if (EV_STATE_DECISION_EVENT == event) sde = 1; if (EV_ANNOUNCE_RECEIPT_TIMEOUT_EXPIRES == event) lost = 1; port_dispatch(c->port[i], event, 0); } } /* Check the fault timer. */ k = N_CLOCK_PFD * i + N_POLLFD; if (c->pollfd[k].revents & (POLLIN|POLLPRI)) { clock_fault_timeout(c, i, 0); port_dispatch(c->port[i], EV_FAULT_CLEARED, 0); } /* Clear any fault after a little while. */ if (PS_FAULTY == port_state(c->port[i])) { clock_fault_timeout(c, i, 1); } } /* Check the UDS port. */ for (j = 0; j < N_POLLFD; j++) { k = N_CLOCK_PFD * i + j; if (c->pollfd[k].revents & (POLLIN|POLLPRI)) { event = port_event(c->port[i], j); } } if (lost && clock_master_lost(c)) clock_update_grandmaster(c); if (sde) handle_state_decision_event(c); return 0; } void clock_path_delay(struct clock *c, struct timespec req, struct timestamp rx, Integer64 correction) { tmv_t c1, c2, c3, pd, t1, t2, t3, t4; if (tmv_is_zero(c->t1)) return; c1 = c->c1; c2 = c->c2; c3 = correction_to_tmv(correction); t1 = c->t1; t2 = c->t2; t3 = timespec_to_tmv(req); t4 = timestamp_to_tmv(rx); /* * c->path_delay = (t2 - t3) + (t4 - t1); * c->path_delay -= c_sync + c_fup + c_delay_resp; * c->path_delay /= 2.0; */ pd = tmv_add(tmv_sub(t2, t3), tmv_sub(t4, t1)); pd = tmv_sub(pd, tmv_add(c1, tmv_add(c2, c3))); pd = tmv_div(pd, 2); if (pd < 0) { pr_warning("negative path delay %10lld", pd); pr_warning("path_delay = (t2 - t3) + (t4 - t1)"); pr_warning("t2 - t3 = %+10lld", t2 - t3); pr_warning("t4 - t1 = %+10lld", t4 - t1); pr_warning("c1 %10lld", c1); pr_warning("c2 %10lld", c2); pr_warning("c3 %10lld", c3); } c->path_delay = mave_accumulate(c->avg_delay, pd); c->cur.meanPathDelay = tmv_to_TimeInterval(c->path_delay); pr_debug("path delay %10lld %10lld", c->path_delay, pd); } void clock_peer_delay(struct clock *c, tmv_t ppd) { c->path_delay = ppd; } void clock_remove_fda(struct clock *c, struct port *p, struct fdarray fda) { int i, j, k; for (i = 0; i < c->nports + 1; i++) { if (p == c->port[i]) break; } for (j = 0; j < N_POLLFD; j++) { k = N_CLOCK_PFD * i + j; c->pollfd[k].fd = -1; c->pollfd[k].events = 0; } } int clock_slave_only(struct clock *c) { return c->dds.slaveOnly; } UInteger16 clock_steps_removed(struct clock *c) { return c->cur.stepsRemoved; } enum servo_state clock_synchronize(struct clock *c, struct timespec ingress_ts, struct timestamp origin_ts, Integer64 correction1, Integer64 correction2) { double adj; tmv_t ingress, origin; enum servo_state state = SERVO_UNLOCKED; ingress = timespec_to_tmv(ingress_ts); origin = timestamp_to_tmv(origin_ts); c->t1 = origin; c->t2 = ingress; c->c1 = correction_to_tmv(correction1); c->c2 = correction_to_tmv(correction2); /* * c->master_offset = ingress - origin - c->path_delay - c->c1 - c->c2; */ c->master_offset = tmv_sub(ingress, tmv_add(origin, tmv_add(c->path_delay, tmv_add(c->c1, c->c2)))); c->cur.offsetFromMaster = tmv_to_TimeInterval(c->master_offset); if (!c->path_delay) return state; if (c->dds.free_running) return clock_no_adjust(c); adj = servo_sample(c->servo, c->master_offset, ingress, &state); pr_info("master offset %10lld s%d adj %+7.0f path delay %10lld", c->master_offset, state, adj, c->path_delay); switch (state) { case SERVO_UNLOCKED: break; case SERVO_JUMP: clock_step(c->clkid, -c->master_offset); c->t1 = tmv_zero(); c->t2 = tmv_zero(); break; case SERVO_LOCKED: clock_ppb(c->clkid, -adj); break; } return state; } void clock_sync_interval(struct clock *c, int n) { int shift = c->dds.freq_est_interval - n; if (shift < 0) shift = 0; c->fest.max_count = (1 << shift); } struct timePropertiesDS *clock_time_properties(struct clock *c) { return &c->tds; } static void handle_state_decision_event(struct clock *c) { struct foreign_clock *best = NULL, *fc; int fresh_best = 0, i; for (i = 0; i < c->nports; i++) { fc = port_compute_best(c->port[i]); if (!fc) continue; if (!best || dscmp(&fc->dataset, &best->dataset) > 0) best = fc; } if (!best) return; pr_notice("selected best master clock %s", cid2str(&best->dataset.identity)); if (c->best != best) { mave_reset(c->avg_delay); fresh_best = 1; } c->best = best; for (i = 0; i < c->nports; i++) { enum port_state ps; enum fsm_event event; ps = bmc_state_decision(c, c->port[i]); switch (ps) { case PS_LISTENING: event = EV_NONE; break; case PS_GRAND_MASTER: clock_update_grandmaster(c); event = EV_RS_GRAND_MASTER; break; case PS_MASTER: event = EV_RS_MASTER; break; case PS_PASSIVE: event = EV_RS_PASSIVE; break; case PS_SLAVE: clock_update_slave(c); event = EV_RS_SLAVE; break; default: event = EV_FAULT_DETECTED; break; } port_dispatch(c->port[i], event, fresh_best); } }