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Diffstat (limited to 'os/kernel/src/chsys.c')
| -rw-r--r-- | os/kernel/src/chsys.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/os/kernel/src/chsys.c b/os/kernel/src/chsys.c new file mode 100644 index 000000000..a6f1d15ba --- /dev/null +++ b/os/kernel/src/chsys.c @@ -0,0 +1,149 @@ +/*
+ 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.
+ * .
+ * @{
+ */
+
+#include "ch.h"
+
+#if !CH_NO_IDLE_THREAD || defined(__DOXYGEN__)
+/**
+ * @brief Idle thread working area.
+ */
+WORKING_AREA(_idle_thread_wa, PORT_IDLE_THREAD_STACK_SIZE);
+
+/**
+ * @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
+ */
+void _idle_thread(void *p) {
+
+ (void)p;
+ chRegSetThreadName("idle");
+ while (TRUE) {
+ port_wait_for_interrupt();
+ IDLE_LOOP_HOOK();
+ }
+}
+#endif /* CH_NO_IDLE_THREAD */
+
+/**
+ * @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 mainthread;
+#if CH_DBG_ENABLE_STACK_CHECK
+ extern stkalign_t __main_thread_stack_base__;
+#endif
+
+ port_init();
+ _scheduler_init();
+ _vt_init();
+#if CH_USE_MEMCORE
+ _core_init();
+#endif
+#if CH_USE_HEAP
+ _heap_init();
+#endif
+#if CH_DBG_ENABLE_TRACE
+ _trace_init();
+#endif
+
+ /* Now this instructions flow becomes the main thread.*/
+ setcurrp(_thread_init(&mainthread, NORMALPRIO));
+ currp->p_state = THD_STATE_CURRENT;
+#if CH_DBG_ENABLE_STACK_CHECK
+ /* This is a special case because the main thread Thread 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_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 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_TIME_QUANTUM macro, the round robin
+ * interval.
+ *
+ * @iclass
+ */
+void chSysTimerHandlerI(void) {
+
+ chDbgCheckClassI();
+
+#if CH_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(SYSTEM_TICK_EVENT_HOOK)
+ SYSTEM_TICK_EVENT_HOOK();
+#endif
+}
+
+/** @} */
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