/**************************************************************************** * sched/clock/clock_timekeeping.c * * Copyright (C) 2016 Gregory Nutt. All rights reserved. * Author: Max Neklyudov * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in * the documentation and/or other materials provided with the * distribution. * 3. Neither the name NuttX nor the names of its contributors may be * used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * ****************************************************************************/ /**************************************************************************** * Included Files ****************************************************************************/ #include #ifdef CONFIG_CLOCK_TIMEKEEPING #include #include #include #include #include #include #include #include "clock/clock.h" /**************************************************************************** * Pre-processor Definitions ****************************************************************************/ #define NTP_MAX_ADJUST 500 /**************************************************************************** * Private Data ****************************************************************************/ static struct timespec g_clock_wall_time; static uint64_t g_clock_last_counter; static uint64_t g_clock_mask; static long g_clock_adjust; /**************************************************************************** * Private Functions ****************************************************************************/ /**************************************************************************** * Name: clock_get_current_time ****************************************************************************/ static int clock_get_current_time(FAR struct timespec *ts, FAR struct timespec *base) { irqstate_t flags; uint64_t counter; uint64_t offset; uint64_t nsec; time_t sec; int ret; flags = enter_critical_section(); ret = up_timer_getcounter(&counter); if (ret < 0) { goto errout_in_critical_section; } offset = (counter - g_clock_last_counter) & g_clock_mask; nsec = offset * NSEC_PER_TICK; sec = nsec / NSEC_PER_SEC; nsec -= sec * NSEC_PER_SEC; nsec += base->tv_nsec; if (nsec >= NSEC_PER_SEC) { nsec -= NSEC_PER_SEC; sec += 1; } ts->tv_nsec = nsec; ts->tv_sec = base->tv_sec + sec; errout_in_critical_section: leave_critical_section(flags); return ret; } /**************************************************************************** * Public Functions ****************************************************************************/ /**************************************************************************** * Name: clock_timekeeping_get_wall_time ****************************************************************************/ int clock_timekeeping_get_wall_time(FAR struct timespec *ts) { return clock_get_current_time(ts, &g_clock_wall_time); } /**************************************************************************** * Name: clock_timekeeping_set_wall_time ****************************************************************************/ int clock_timekeeping_set_wall_time(FAR struct timespec *ts) { irqstate_t flags; uint64_t counter; int ret; flags = enter_critical_section(); ret = up_timer_getcounter(&counter); if (ret < 0) { goto errout_in_critical_section; } g_clock_wall_time = *ts; g_clock_adjust = 0; g_clock_last_counter = counter; errout_in_critical_section: leave_critical_section(flags); return ret; } /**************************************************************************** * Name: adjtime * * Description: * The adjtime() function gradually adjusts the system clock (as returned * by gettimeofday(2)). The amount of time by which the clock is to be * adjusted is specified in the structure pointed to by delta. * * This structure has the following form: * * struct timeval * { * time_t tv_sec; (seconds) * suseconds_t tv_usec; (microseconds) * }; * * If the adjustment in delta is positive, then the system clock is * speeded up by some small percentage (i.e., by adding a small amount of * time to the clock value in each second) until the adjustment has been * completed. If the adjustment in delta is negative, then the clock is * slowed down in a similar fashion. * * If a clock adjustment from an earlier adjtime() call is already in * progress at the time of a later adjtime() call, and delta is not NULL * for the later call, then the earlier adjustment is stopped, but any * already completed part of that adjustment is not undone. * * If olddelta is not NULL, then the buffer that it points to is used to * return the amount of time remaining from any previous adjustment that * has not yet been completed. * * NOTE: This is not a POSIX interface but derives from 4.3BSD, System V. * It is also supported for Linux compatibility. * ****************************************************************************/ int adjtime(FAR const struct timeval *delta, FAR struct timeval *olddelta) { irqstate_t flags; long adjust_usec; if (!delta) { set_errno(EINVAL); return -1; } flags = enter_critical_section(); adjust_usec = delta->tv_sec * USEC_PER_SEC + delta->tv_usec; if (olddelta) { olddelta->tv_usec = g_clock_adjust; } g_clock_adjust = adjust_usec; leave_critical_section(flags); return OK; } /**************************************************************************** * Name: clock_update_wall_time ****************************************************************************/ void clock_update_wall_time(void) { irqstate_t flags; uint64_t counter; uint64_t offset; int64_t nsec; time_t sec; int ret; flags = enter_critical_section(); ret = up_timer_getcounter(&counter); if (ret < 0) { goto errout_in_critical_section; } offset = (counter - g_clock_last_counter) & g_clock_mask; if (offset == 0) { goto errout_in_critical_section; } nsec = offset * NSEC_PER_TICK; sec = nsec / NSEC_PER_SEC; nsec -= sec * NSEC_PER_SEC; nsec += g_clock_wall_time.tv_nsec; if (nsec >= NSEC_PER_SEC) { nsec -= NSEC_PER_SEC; sec += 1; } if (g_clock_adjust != 0 && sec > 0) { long adjust = NTP_MAX_ADJUST * (long)sec; if (g_clock_adjust < adjust && g_clock_adjust > -adjust) { adjust = g_clock_adjust; } nsec += adjust * NSEC_PER_USEC; while (nsec < 0) { nsec += NSEC_PER_SEC; sec -= 1; } while (nsec >= NSEC_PER_SEC) { nsec -= NSEC_PER_SEC; sec += 1; } } g_clock_wall_time.tv_sec += sec; g_clock_wall_time.tv_nsec = (long)nsec; g_clock_last_counter = counter; errout_in_critical_section: leave_critical_section(flags); } /**************************************************************************** * Name: clock_inittimekeeping ****************************************************************************/ void clock_inittimekeeping(void) { up_timer_getmask(&g_clock_mask); clock_basetime(&g_clock_wall_time); up_timer_getcounter(&g_clock_last_counter); } #endif /* CONFIG_CLOCK_TIMEKEEPING */