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Diffstat (limited to 'nuttx/sched/clock_initialize.c')
-rw-r--r-- | nuttx/sched/clock_initialize.c | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/nuttx/sched/clock_initialize.c b/nuttx/sched/clock_initialize.c new file mode 100644 index 000000000..2e146bb47 --- /dev/null +++ b/nuttx/sched/clock_initialize.c @@ -0,0 +1,270 @@ +/**************************************************************************** + * sched/clock_initialize.c + * + * Copyright (C) 2007, 2009, 2011-2012 Gregory Nutt. All rights reserved. + * Author: Gregory Nutt <gnutt@nuttx.org> + * + * 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 <nuttx/config.h> +#include <nuttx/compiler.h> + +#include <stdint.h> +#include <time.h> +#include <errno.h> +#include <debug.h> + +#ifdef CONFIG_RTC +# include <arch/irq.h> +#endif + +#include <nuttx/clock.h> +#include <nuttx/time.h> +#include <nuttx/rtc.h> + +#include "clock_internal.h" + +/**************************************************************************** + * Definitions + ****************************************************************************/ +/* Standard time definitions (in units of seconds) */ + +#define SEC_PER_MIN ((time_t)60) +#define SEC_PER_HOUR ((time_t)60 * SEC_PER_MIN) +#define SEC_PER_DAY ((time_t)24 * SEC_PER_HOUR) + +/**************************************************************************** + * Private Type Declarations + ****************************************************************************/ + +/**************************************************************************** + * Private Function Prototypes + ****************************************************************************/ + +/************************************************************************** + * Public Constant Data + **************************************************************************/ + +/**************************************************************************** + * Public Variables + ****************************************************************************/ + +#ifdef CONFIG_SYSTEM_TIME64 +volatile uint64_t g_system_timer; +uint64_t g_tickbias; +#else +volatile uint32_t g_system_timer; +uint32_t g_tickbias; +#endif + +struct timespec g_basetime; + +/************************************************************************** + * Private Variables + **************************************************************************/ + +/************************************************************************** + * Private Functions + **************************************************************************/ + +/**************************************************************************** + * Name: clock_basetime + * + * Description: + * Get the initial time value from the best source available. + * + ****************************************************************************/ + +#ifdef CONFIG_RTC +#if defined(CONFIG_RTC_DATETIME) +/* Initialize the system time using a broken out date/time structure */ + +static inline void clock_basetime(FAR struct timespec *tp) +{ + struct tm rtctime; + + /* Get the broken-out time from the date/time RTC. */ + + (void)up_rtc_getdatetime(&rtctime); + + /* And use the broken-out time to initialize the system time */ + + tp->tv_sec = mktime(&rtctime); + tp->tv_nsec = 0; +} + +#elif defined(CONFIG_RTC_HIRES) + +/* Initialize the system time using a high-resolution structure */ + +static inline void clock_basetime(FAR struct timespec *tp) +{ + /* Get the complete time from the hi-res RTC. */ + + (void)up_rtc_gettime(tp); +} + +#else + +/* Initialize the system time using seconds only */ + +static inline void clock_basetime(FAR struct timespec *tp) +{ + /* Get the seconds (only) from the lo-resolution RTC */ + + tp->tv_sec = up_rtc_time(); + tp->tv_nsec = 0; +} + +#endif /* CONFIG_RTC_HIRES */ +#else /* CONFIG_RTC */ + +static inline void clock_basetime(FAR struct timespec *tp) +{ + time_t jdn = 0; + + /* Get the EPOCH-relative julian date from the calendar year, + * month, and date + */ + + jdn = clock_calendar2utc(CONFIG_START_YEAR, CONFIG_START_MONTH, + CONFIG_START_DAY); + + /* Set the base time as seconds into this julian day. */ + + tp->tv_sec = jdn * SEC_PER_DAY; + tp->tv_nsec = 0; +} + +#endif /* CONFIG_RTC */ + +/**************************************************************************** + * Name: clock_inittime + * + * Description: + * Get the initial time value from the best source available. + * + ****************************************************************************/ + +static void clock_inittime(void) +{ + /* (Re-)initialize the time value to match the RTC*/ + + clock_basetime(&g_basetime); + g_system_timer = 0; + g_tickbias = 0; +} + +/**************************************************************************** + * Public Functions + ****************************************************************************/ + +/**************************************************************************** + * Name: clock_initialize + * + * Description: + * Perform one-time initialization of the timing facilities. + * + ****************************************************************************/ + +void clock_initialize(void) +{ + /* Initialize the RTC hardware */ + +#ifdef CONFIG_RTC + up_rtcinitialize(); +#endif + + /* Initialize the time value to match the RTC */ + + clock_inittime(); +} + +/**************************************************************************** + * Name: clock_synchronize + * + * Description: + * Synchronize the system timer to a hardware RTC. This operation is + * normally performed automatically by the system during clock + * initialization. However, the user may also need to explicitly re- + * synchronize the system timer to the RTC under certain conditions where + * the system timer is known to be in error. For example, in certain low- + * power states, the system timer may be stopped but the RTC will continue + * keep correct time. After recovering from such low-power state, this + * function should be called to restore the correct system time. + * + * Calling this function could result in system time going "backward" in + * time, especially with certain lower resolution RTC implementations. + * Time going backward could have bad consequences if there are ongoing + * timers and delays. So use this interface with care. + * + * Parameters: + * None + * + * Return Value: + * None + * + * Assumptions: + * + ****************************************************************************/ + +#ifdef CONFIG_RTC +void clock_synchronize(void) +{ + irqstate_t flags; + + /* Re-initialize the time value to match the RTC */ + + flags = irqsave(); + clock_inittime(); + irqrestore(flags); +} +#endif + +/**************************************************************************** + * Name: clock_timer + * + * Description: + * This function must be called once every time the real time clock + * interrupt occurs. The interval of this clock interrupt must be + * MSEC_PER_TICK + * + ****************************************************************************/ + +void clock_timer(void) +{ + /* Increment the per-tick system counter */ + + g_system_timer++; +} |