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Diffstat (limited to 'os/rt/src/chsys.c')
| -rw-r--r-- | os/rt/src/chsys.c | 303 |
1 files changed, 303 insertions, 0 deletions
diff --git a/os/rt/src/chsys.c b/os/rt/src/chsys.c new file mode 100644 index 000000000..f7fd6766b --- /dev/null +++ b/os/rt/src/chsys.c @@ -0,0 +1,303 @@ +/*
+ ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
+ 2011,2012,2013 Giovanni Di Sirio.
+
+ This file is part of ChibiOS/RT.
+
+ ChibiOS/RT 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/RT 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 <http://www.gnu.org/licenses/>.
+*/
+
+/**
+ * @file chsys.c
+ * @brief System related code.
+ *
+ * @addtogroup system
+ * @details System related APIs and services:
+ * - Initialization.
+ * - Locks.
+ * - Interrupt Handling.
+ * - Power Management.
+ * - Abnormal Termination.
+ * - Realtime counter.
+ * .
+ * @{
+ */
+
+#include "ch.h"
+
+/*===========================================================================*/
+/* Module exported variables. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module local types. */
+/*===========================================================================*/
+
+/*===========================================================================*/
+/* Module local variables. */
+/*===========================================================================*/
+
+#if !CH_CFG_NO_IDLE_THREAD || defined(__DOXYGEN__)
+/**
+ * @brief Idle thread working area.
+ */
+static THD_WORKING_AREA(_idle_thread_wa, PORT_IDLE_THREAD_STACK_SIZE);
+#endif /* CH_CFG_NO_IDLE_THREAD */
+
+/*===========================================================================*/
+/* Module local functions. */
+/*===========================================================================*/
+
+#if !CH_CFG_NO_IDLE_THREAD || defined(__DOXYGEN__)
+/**
+ * @brief This function implements the idle thread infinite loop.
+ * @details The function puts the processor in the lowest power mode capable
+ * to serve interrupts.<br>
+ * The priority is internally set to the minimum system value so
+ * that this thread is executed only if there are no other ready
+ * threads in the system.
+ *
+ * @param[in] p the thread parameter, unused in this scenario
+ */
+static void _idle_thread(void *p) {
+
+ (void)p;
+ chRegSetThreadName("idle");
+ while (true) {
+ port_wait_for_interrupt();
+ CH_CFG_IDLE_LOOP_HOOK();
+ }
+}
+#endif /* CH_CFG_NO_IDLE_THREAD */
+
+/*===========================================================================*/
+/* Module exported functions. */
+/*===========================================================================*/
+
+/**
+ * @brief ChibiOS/RT initialization.
+ * @details After executing this function the current instructions stream
+ * becomes the main thread.
+ * @pre Interrupts must be still disabled when @p chSysInit() is invoked
+ * and are internally enabled.
+ * @post The main thread is created with priority @p NORMALPRIO.
+ * @note This function has special, architecture-dependent, requirements,
+ * see the notes into the various port reference manuals.
+ *
+ * @special
+ */
+void chSysInit(void) {
+ static thread_t mainthread;
+#if CH_DBG_ENABLE_STACK_CHECK
+ extern stkalign_t __main_thread_stack_base__;
+#endif
+
+ port_init();
+ _scheduler_init();
+ _vt_init();
+#if CH_CFG_USE_TM
+ _tm_init();
+#endif
+#if CH_CFG_USE_MEMCORE
+ _core_init();
+#endif
+#if CH_CFG_USE_HEAP
+ _heap_init();
+#endif
+#if CH_DBG_STATISTICS
+ _stats_init();
+#endif
+#if CH_DBG_ENABLE_TRACE
+ _trace_init();
+#endif
+
+#if !CH_CFG_NO_IDLE_THREAD
+ /* Now this instructions flow becomes the main thread.*/
+ setcurrp(_thread_init(&mainthread, NORMALPRIO));
+#else
+ /* Now this instructions flow becomes the main thread.*/
+ setcurrp(_thread_init(&mainthread, IDLEPRIO));
+#endif
+
+ currp->p_state = CH_STATE_CURRENT;
+#if CH_DBG_ENABLE_STACK_CHECK
+ /* This is a special case because the main thread thread_t structure is not
+ adjacent to its stack area.*/
+ currp->p_stklimit = &__main_thread_stack_base__;
+#endif
+ chSysEnable();
+
+ /* Note, &ch_debug points to the string "main" if the registry is
+ active, else the parameter is ignored.*/
+ chRegSetThreadName((const char *)&ch_debug);
+
+#if !CH_CFG_NO_IDLE_THREAD
+ /* This thread has the lowest priority in the system, its role is just to
+ serve interrupts in its context while keeping the lowest energy saving
+ mode compatible with the system status.*/
+ chThdCreateStatic(_idle_thread_wa, sizeof(_idle_thread_wa), IDLEPRIO,
+ (tfunc_t)_idle_thread, NULL);
+#endif
+}
+
+/**
+ * @brief Halts the system.
+ * @details This function is invoked by the operating system when an
+ * unrecoverable error is detected, for example because a programming
+ * error in the application code that triggers an assertion while
+ * in debug mode.
+ * @note Can be invoked from any system state.
+ *
+ * @special
+ */
+void chSysHalt(const char *reason) {
+
+ port_disable();
+
+#if CH_DBG_ENABLED
+ ch.dbg_panic_msg = reason;
+#else
+ (void)reason;
+#endif
+
+#if defined(CH_CFG_SYSTEM_HALT_HOOK) || defined(__DOXYGEN__)
+ CH_CFG_SYSTEM_HALT_HOOK(reason);
+#endif
+
+ /* Harmless infinite loop.*/
+ while (true)
+ ;
+}
+
+/**
+ * @brief Handles time ticks for round robin preemption and timer increments.
+ * @details Decrements the remaining time quantum of the running thread
+ * and preempts it when the quantum is used up. Increments system
+ * time and manages the timers.
+ * @note The frequency of the timer determines the system tick granularity
+ * and, together with the @p CH_CFG_TIME_QUANTUM macro, the round robin
+ * interval.
+ *
+ * @iclass
+ */
+void chSysTimerHandlerI(void) {
+
+ chDbgCheckClassI();
+
+#if CH_CFG_TIME_QUANTUM > 0
+ /* Running thread has not used up quantum yet? */
+ if (currp->p_preempt > 0)
+ /* Decrement remaining quantum.*/
+ currp->p_preempt--;
+#endif
+#if CH_DBG_THREADS_PROFILING
+ currp->p_time++;
+#endif
+ chVTDoTickI();
+#if defined(CH_CFG_SYSTEM_TICK_HOOK)
+ CH_CFG_SYSTEM_TICK_HOOK();
+#endif
+}
+
+/**
+ * @brief Returns the execution status and enters a critical zone.
+ * @details This functions enters into a critical zone and can be called
+ * from any context. Because its flexibility it is less efficient
+ * than @p chSysLock() which is preferable when the calling context
+ * is known.
+ * @post The system is in a critical zone.
+ *
+ * @return The previous system status, the encoding of this
+ * status word is architecture-dependent and opaque.
+ *
+ * @xclass
+ */
+syssts_t chSysGetStatusAndLockX(void) {
+
+ syssts_t sts = port_get_irq_status();
+ if (port_irq_enabled(sts)) {
+ if (port_is_isr_context())
+ chSysLockFromISR();
+ else
+ chSysLock();
+ }
+ return sts;
+}
+
+/**
+ * @brief Restores the specified execution status and leaves a critical zone.
+ * @note A call to @p chSchRescheduleS() is automatically performed
+ * if exiting the critical zone and if not in ISR context.
+ *
+ * @param[in] sts the system status to be restored.
+ *
+ * @xclass
+ */
+void chSysRestoreStatusX(syssts_t sts) {
+
+ if (port_irq_enabled(sts)) {
+ if (port_is_isr_context())
+ chSysUnlockFromISR();
+ else {
+ chSchRescheduleS();
+ chSysUnlock();
+ }
+ }
+}
+
+#if PORT_SUPPORTS_RT || defined(__DOXYGEN__)
+/**
+ * @brief Realtime window test.
+ * @details This function verifies if the current realtime counter value
+ * lies within the specified range or not. The test takes care
+ * of the realtime counter wrapping to zero on overflow.
+ * @note When start==end then the function returns always true because the
+ * whole time range is specified.
+ * @note This function is only available if the port layer supports the
+ * option @p PORT_SUPPORTS_RT.
+ *
+ * @param[in] cnt the counter value to be tested
+ * @param[in] start the start of the time window (inclusive)
+ * @param[in] end the end of the time window (non inclusive)
+ * @retval true current time within the specified time window.
+ * @retval false current time not within the specified time window.
+ *
+ * @xclass
+ */
+bool chSysIsCounterWithinX(rtcnt_t cnt, rtcnt_t start, rtcnt_t end) {
+
+ return end > start ? (cnt >= start) && (cnt < end) :
+ (cnt >= start) || (cnt < end);
+}
+
+/**
+ * @brief Polled delay.
+ * @note The real delay is always few cycles in excess of the specified
+ * value.
+ * @note This function is only available if the port layer supports the
+ * option @p PORT_SUPPORTS_RT.
+ *
+ * @param[in] cycles number of cycles
+ *
+ * @xclass
+ */
+void chSysPolledDelayX(rtcnt_t cycles) {
+ rtcnt_t start = chSysGetRealtimeCounterX();
+ rtcnt_t end = start + cycles;
+ while (chSysIsCounterWithinX(chSysGetRealtimeCounterX(), start, end))
+ ;
+}
+#endif /* PORT_SUPPORTS_RT */
+
+/** @} */
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