/* ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010, 2011 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 . */ /** * @file MSP430/chcore.c * @brief MSP430 architecture port code. * * @addtogroup MSP430_CORE * @{ */ #include "ch.h" /** * @brief Performs a context switch between two threads. * @details This is the most critical code in any port, this function * is responsible for the context switch between 2 threads. * @note The implementation of this code affects directly the context * switch performance so optimize here as much as you can. * @note The function is declared as a weak symbol, it is possible to * redefine it in your application code. * * @param[in] ntp the thread to be switched in * @param[in] otp the thread to be switched out */ #if !defined(__DOXYGEN__) __attribute__((naked, weak)) #endif void port_switch(Thread *ntp, Thread *otp) { register struct intctx *sp asm("r1"); asm volatile ("push r11 \n\t" \ "push r10 \n\t" \ "push r9 \n\t" \ "push r8 \n\t" \ "push r7 \n\t" \ "push r6 \n\t" \ "push r5 \n\t" \ "push r4" : : : "memory"); otp->p_ctx.sp = sp; sp = ntp->p_ctx.sp; asm volatile ("pop r4 \n\t" \ "pop r5 \n\t" \ "pop r6 \n\t" \ "pop r7 \n\t" \ "pop r8 \n\t" \ "pop r9 \n\t" \ "pop r10 \n\t" \ "pop r11 \n\t" \ "ret" : : "r" (sp) : "memory"); } /** * @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 The function is declared as a weak symbol, it is possible to * redefine it in your application code. */ #if !defined(__DOXYGEN__) __attribute__((weak)) #endif void port_halt(void) { port_disable(); while (TRUE) { } } /** * @brief Start a thread by invoking its work function. * @details If the work function returns @p chThdExit() is automatically * invoked. */ void _port_thread_start(void) { chSysUnlock(); asm volatile ("mov r11, r15 \n\t" \ "call r10 \n\t" \ "call #chThdExit"); } /** @} */