ChibiOS/ports/AVR/chcore.c

138 lines
4.0 KiB
C

/*
ChibiOS/RT - Copyright (C) 2006-2007 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/>.
*/
/**
* @addtogroup AVR_CORE
* @{
*/
#include <ch.h>
/*
* This file is a template of the system driver functions provided by a port.
* Some of the following functions may be implemented as macros in chcore.h if
* the implementer decides that there is an advantage in doing so, as example
* because performance concerns.
*/
/**
* The default implementation of this function is void so no messages are
* actually printed.
* @note The function is declared as a weak symbol, it is possible to redefine
* it in your application code.
* @param msg pointer to the message string
*/
__attribute__((weak))
void sys_puts(char *msg) {
}
/**
* Performs a context switch between two threads.
* @param otp the thread to be switched out
* @param ntp the thread to be switched in
* @note The function is declared as a weak symbol, it is possible to redefine
* it in your application code.
*/
__attribute__((naked, weak))
void sys_switch(Thread *otp, Thread *ntp) {
asm volatile ("push r2");
asm volatile ("push r3");
asm volatile ("push r4");
asm volatile ("push r5");
asm volatile ("push r6");
asm volatile ("push r7");
#ifndef CH_CURRP_REGISTER_CACHE
asm volatile ("push r8");
asm volatile ("push r9");
#endif
asm volatile ("push r10");
asm volatile ("push r11");
asm volatile ("push r12");
asm volatile ("push r13");
asm volatile ("push r14");
asm volatile ("push r15");
asm volatile ("push r16");
asm volatile ("push r17");
asm volatile ("push r28");
asm volatile ("push r29");
asm volatile ("movw r30, r24");
asm volatile ("in r0, 0x3d");
asm volatile ("std Z+8, r0");
asm volatile ("in r0, 0x3e");
asm volatile ("std Z+9, r0");
asm volatile ("movw r30, r22");
asm volatile ("ldd r0, Z+8");
asm volatile ("out 0x3d, r0");
asm volatile ("ldd r0, Z+9");
asm volatile ("out 0x3e, r0");
asm volatile ("pop r29");
asm volatile ("pop r28");
asm volatile ("pop r17");
asm volatile ("pop r16");
asm volatile ("pop r15");
asm volatile ("pop r14");
asm volatile ("pop r13");
asm volatile ("pop r12");
asm volatile ("pop r11");
asm volatile ("pop r10");
#ifndef CH_CURRP_REGISTER_CACHE
asm volatile ("pop r9");
asm volatile ("pop r8");
#endif
asm volatile ("pop r7");
asm volatile ("pop r6");
asm volatile ("pop r5");
asm volatile ("pop r4");
asm volatile ("pop r3");
asm volatile ("pop r2");
asm volatile ("ret");
}
/**
* Disables the interrupts and halts the system.
* @note The function is declared as a weak symbol, it is possible to redefine
* it in your application code.
*/
__attribute__((weak))
void sys_halt(void) {
sys_disable();
while (TRUE) {
}
}
/**
* Start a thread by invoking its work function.
* If the work function returns @p chThdExit() is automatically invoked.
*/
void threadstart(void) {
asm volatile ("sei");
asm volatile ("movw r24, r4");
asm volatile ("movw r30, r2");
asm volatile ("icall");
asm volatile ("call chThdExit");
}
/** @} */