/*
ChibiOS - Copyright (C) 2006..2015 Giovanni Di Sirio.
This file is part of ChibiOS.
ChibiOS 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 3 of the License, or
(at your option) any later version.
ChibiOS 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, see .
*/
/**
* @file chsys.h
* @brief System related macros and structures.
*
* @addtogroup system
* @{
*/
#ifndef _CHSYS_H_
#define _CHSYS_H_
/*lint -sem(chSysHalt, r_no)*/
/*===========================================================================*/
/* Module constants. */
/*===========================================================================*/
/*===========================================================================*/
/* Module pre-compile time settings. */
/*===========================================================================*/
/*===========================================================================*/
/* Derived constants and error checks. */
/*===========================================================================*/
/*===========================================================================*/
/* Module data structures and types. */
/*===========================================================================*/
/*===========================================================================*/
/* Module macros. */
/*===========================================================================*/
/**
* @name ISRs abstraction macros
*/
/**
* @brief IRQ handler enter code.
* @note Usually IRQ handlers functions are also declared naked.
* @note On some architectures this macro can be empty.
*
* @special
*/
#define CH_IRQ_PROLOGUE() \
PORT_IRQ_PROLOGUE(); \
_stats_increase_irq(); \
_dbg_check_enter_isr()
/**
* @brief IRQ handler exit code.
* @note Usually IRQ handlers function are also declared naked.
* @note This macro usually performs the final reschedule by using
* @p chSchIsPreemptionRequired() and @p chSchDoReschedule().
*
* @special
*/
#define CH_IRQ_EPILOGUE() \
_dbg_check_leave_isr(); \
PORT_IRQ_EPILOGUE()
/**
* @brief Standard normal IRQ handler declaration.
* @note @p id can be a function name or a vector number depending on the
* port implementation.
*
* @special
*/
#define CH_IRQ_HANDLER(id) PORT_IRQ_HANDLER(id)
/** @} */
/**
* @name Fast ISRs abstraction macros
*/
/**
* @brief Standard fast IRQ handler declaration.
* @note @p id can be a function name or a vector number depending on the
* port implementation.
* @note Not all architectures support fast interrupts.
*
* @special
*/
#define CH_FAST_IRQ_HANDLER(id) PORT_FAST_IRQ_HANDLER(id)
/** @} */
/**
* @name Time conversion utilities for the realtime counter
* @{
*/
/**
* @brief Seconds to realtime counter.
* @details Converts from seconds to realtime counter cycles.
* @note The macro assumes that @p freq >= @p 1.
*
* @param[in] freq clock frequency, in Hz, of the realtime counter
* @param[in] sec number of seconds
* @return The number of cycles.
*
* @api
*/
#define S2RTC(freq, sec) ((freq) * (sec))
/**
* @brief Milliseconds to realtime counter.
* @details Converts from milliseconds to realtime counter cycles.
* @note The result is rounded upward to the next millisecond boundary.
* @note The macro assumes that @p freq >= @p 1000.
*
* @param[in] freq clock frequency, in Hz, of the realtime counter
* @param[in] msec number of milliseconds
* @return The number of cycles.
*
* @api
*/
#define MS2RTC(freq, msec) (rtcnt_t)((((freq) + 999UL) / 1000UL) * (msec))
/**
* @brief Microseconds to realtime counter.
* @details Converts from microseconds to realtime counter cycles.
* @note The result is rounded upward to the next microsecond boundary.
* @note The macro assumes that @p freq >= @p 1000000.
*
* @param[in] freq clock frequency, in Hz, of the realtime counter
* @param[in] usec number of microseconds
* @return The number of cycles.
*
* @api
*/
#define US2RTC(freq, usec) (rtcnt_t)((((freq) + 999999UL) / 1000000UL) * (usec))
/**
* @brief Realtime counter cycles to seconds.
* @details Converts from realtime counter cycles number to seconds.
* @note The result is rounded up to the next second boundary.
* @note The macro assumes that @p freq >= @p 1.
*
* @param[in] freq clock frequency, in Hz, of the realtime counter
* @param[in] n number of cycles
* @return The number of seconds.
*
* @api
*/
#define RTC2S(freq, n) ((((n) - 1UL) / (freq)) + 1UL)
/**
* @brief Realtime counter cycles to milliseconds.
* @details Converts from realtime counter cycles number to milliseconds.
* @note The result is rounded up to the next millisecond boundary.
* @note The macro assumes that @p freq >= @p 1000.
*
* @param[in] freq clock frequency, in Hz, of the realtime counter
* @param[in] n number of cycles
* @return The number of milliseconds.
*
* @api
*/
#define RTC2MS(freq, n) ((((n) - 1UL) / ((freq) / 1000UL)) + 1UL)
/**
* @brief Realtime counter cycles to microseconds.
* @details Converts from realtime counter cycles number to microseconds.
* @note The result is rounded up to the next microsecond boundary.
* @note The macro assumes that @p freq >= @p 1000000.
*
* @param[in] freq clock frequency, in Hz, of the realtime counter
* @param[in] n number of cycles
* @return The number of microseconds.
*
* @api
*/
#define RTC2US(freq, n) ((((n) - 1UL) / ((freq) / 1000000UL)) + 1UL)
/** @} */
/**
* @brief Returns the current value of the system real time counter.
* @note This function is only available if the port layer supports the
* option @p PORT_SUPPORTS_RT.
*
* @return The value of the system realtime counter of
* type rtcnt_t.
*
* @xclass
*/
#if (PORT_SUPPORTS_RT == TRUE) || defined(__DOXYGEN__)
#define chSysGetRealtimeCounterX() (rtcnt_t)port_rt_get_counter_value()
#endif
/**
* @brief Performs a context switch.
* @note Not a user function, it is meant to be invoked by the scheduler
* itself or from within the port layer.
*
* @param[in] ntp the thread to be switched in
* @param[in] otp the thread to be switched out
*
* @special
*/
#define chSysSwitch(ntp, otp) { \
\
_dbg_trace(otp); \
_stats_ctxswc(ntp, otp); \
CH_CFG_CONTEXT_SWITCH_HOOK(ntp, otp); \
port_switch(ntp, otp); \
}
/*===========================================================================*/
/* External declarations. */
/*===========================================================================*/
#ifdef __cplusplus
extern "C" {
#endif
void chSysInit(void);
void chSysHalt(const char *reason);
void chSysTimerHandlerI(void);
syssts_t chSysGetStatusAndLockX(void);
void chSysRestoreStatusX(syssts_t sts);
#if PORT_SUPPORTS_RT
bool chSysIsCounterWithinX(rtcnt_t cnt, rtcnt_t start, rtcnt_t end);
void chSysPolledDelayX(rtcnt_t cycles);
#endif
#ifdef __cplusplus
}
#endif
/*===========================================================================*/
/* Module inline functions. */
/*===========================================================================*/
/**
* @brief Raises the system interrupt priority mask to the maximum level.
* @details All the maskable interrupt sources are disabled regardless their
* hardware priority.
* @note Do not invoke this API from within a kernel lock.
*
* @special
*/
static inline void chSysDisable(void) {
port_disable();
_dbg_check_disable();
}
/**
* @brief Raises the system interrupt priority mask to system level.
* @details The interrupt sources that should not be able to preempt the kernel
* are disabled, interrupt sources with higher priority are still
* enabled.
* @note Do not invoke this API from within a kernel lock.
* @note This API is no replacement for @p chSysLock(), the @p chSysLock()
* could do more than just disable the interrupts.
*
* @special
*/
static inline void chSysSuspend(void) {
port_suspend();
_dbg_check_suspend();
}
/**
* @brief Lowers the system interrupt priority mask to user level.
* @details All the interrupt sources are enabled.
* @note Do not invoke this API from within a kernel lock.
* @note This API is no replacement for @p chSysUnlock(), the
* @p chSysUnlock() could do more than just enable the interrupts.
*
* @special
*/
static inline void chSysEnable(void) {
_dbg_check_enable();
port_enable();
}
/**
* @brief Enters the kernel lock state.
*
* @special
*/
static inline void chSysLock(void) {
port_lock();
_stats_start_measure_crit_thd();
_dbg_check_lock();
}
/**
* @brief Leaves the kernel lock state.
*
* @special
*/
static inline void chSysUnlock(void) {
_dbg_check_unlock();
_stats_stop_measure_crit_thd();
/* The following condition can be triggered by the use of i-class functions
in a critical section not followed by a chSchResceduleS(), this means
that the current thread has a lower priority than the next thread in
the ready list.*/
chDbgAssert(ch.rlist.r_current->p_prio >= ch.rlist.r_queue.p_next->p_prio,
"priority violation, missing reschedule");
port_unlock();
}
/**
* @brief Enters the kernel lock state from within an interrupt handler.
* @note This API may do nothing on some architectures, it is required
* because on ports that support preemptable interrupt handlers
* it is required to raise the interrupt mask to the same level of
* the system mutual exclusion zone.
* It is good practice to invoke this API before invoking any I-class
* syscall from an interrupt handler.
* @note This API must be invoked exclusively from interrupt handlers.
*
* @special
*/
static inline void chSysLockFromISR(void) {
port_lock_from_isr();
_stats_start_measure_crit_isr();
_dbg_check_lock_from_isr();
}
/**
* @brief Leaves the kernel lock state from within an interrupt handler.
*
* @note This API may do nothing on some architectures, it is required
* because on ports that support preemptable interrupt handlers
* it is required to raise the interrupt mask to the same level of
* the system mutual exclusion zone.
* It is good practice to invoke this API after invoking any I-class
* syscall from an interrupt handler.
* @note This API must be invoked exclusively from interrupt handlers.
*
* @special
*/
static inline void chSysUnlockFromISR(void) {
_dbg_check_unlock_from_isr();
_stats_stop_measure_crit_isr();
port_unlock_from_isr();
}
/**
* @brief Unconditionally enters the kernel lock state.
* @note Can be called without previous knowledge of the current lock state.
* The final state is "s-locked".
*
* @special
*/
static inline void chSysUnconditionalLock(void) {
if (port_irq_enabled(port_get_irq_status())) {
chSysLock();
}
}
/**
* @brief Unconditionally leaves the kernel lock state.
* @note Can be called without previous knowledge of the current lock state.
* The final state is "normal".
*
* @special
*/
static inline void chSysUnconditionalUnlock(void) {
if (!port_irq_enabled(port_get_irq_status())) {
chSysUnlock();
}
}
#if (CH_CFG_NO_IDLE_THREAD == FALSE) || defined(__DOXYGEN__)
/**
* @brief Returns a pointer to the idle thread.
* @pre In order to use this function the option @p CH_CFG_NO_IDLE_THREAD
* must be disabled.
* @note The reference counter of the idle thread is not incremented but
* it is not strictly required being the idle thread a static
* object.
*
* @return Pointer to the idle thread.
*
* @xclass
*/
static inline thread_t *chSysGetIdleThreadX(void) {
return ch.rlist.r_queue.p_prev;
}
#endif /* CH_CFG_NO_IDLE_THREAD == FALSE */
#endif /* _CHSYS_H_ */
/** @} */