236 lines
6.8 KiB
C
236 lines
6.8 KiB
C
/*
|
|
* Copyright (c) 2006, Technical University of Munich
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
* 3. Neither the name of the Institute nor the names of its contributors
|
|
* may be used to endorse or promote products derived from this software
|
|
* without specific prior written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
|
|
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
* ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
|
|
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*
|
|
* This file is part of the Contiki operating system.
|
|
*
|
|
* \file AVR specific implementation of multithreading architecture
|
|
*
|
|
* \author Adam Dunkels <adam@sics.se>
|
|
* \author Simon Barner <barner@in.tum.de>
|
|
*
|
|
*/
|
|
|
|
#include <avr/io.h>
|
|
#include <avr/interrupt.h>
|
|
#include <stdio.h>
|
|
#include "sys/mt.h"
|
|
#include "dev/rs232.h"
|
|
|
|
/*--------------------------------------------------------------------------*/
|
|
void
|
|
mtarch_init(void)
|
|
{
|
|
|
|
}
|
|
/*--------------------------------------------------------------------------*/
|
|
void
|
|
mtarch_start(struct mtarch_thread *t,
|
|
void (*function)(void *), void *data)
|
|
{
|
|
/* Initialize stack with number sequence (used for
|
|
* measuring stack usage */
|
|
uint8_t i;
|
|
|
|
for(i = 0; i < MTARCH_STACKSIZE; ++i) {
|
|
t->stack[i] = i;
|
|
}
|
|
|
|
/*
|
|
* Push pointer to mt_exit and the thread onto our stack:
|
|
* Caveats:
|
|
* - The stack is defined as an array of bytes, but pointers are 16 bit wide
|
|
* - Function pointers are 16-bit addresses in flash ROM, but e.g.
|
|
* avr-objdump displays byte addresses
|
|
* - Get the high and low byte of the addresses onto the stack in the
|
|
* right order
|
|
*/
|
|
|
|
/* Initialize stack. This is done in reverse order ("pushing") the
|
|
* pre-allocated array */
|
|
|
|
/* mt_exit function that is to be invoked if the thread dies */
|
|
t->stack[MTARCH_STACKSIZE - 1] = (unsigned char)((unsigned short)mt_exit) & 0xff;
|
|
t->stack[MTARCH_STACKSIZE - 2] = (unsigned char)((unsigned short)mt_exit >> 8) & 0xff;
|
|
|
|
/* The thread handler. Invoked when RET is called in mtarch_exec */
|
|
t->stack[MTARCH_STACKSIZE - 3] = (unsigned char)((unsigned short)function) & 0xff;
|
|
t->stack[MTARCH_STACKSIZE - 4] = (unsigned char)((unsigned short)function >> 8) & 0xff;
|
|
|
|
/* Register r0-r23 in t->stack[MTARCH_STACKSIZE - 5] to
|
|
* t->stack[MTARCH_STACKSIZE - 28].
|
|
*
|
|
* Per calling convention, the argument to the thread handler function
|
|
* (i.e. the 'data' pointer) is passed via r24-r25.
|
|
* See http://www.nongnu.org/avr-libc/user-manual/FAQ.html#faq_reg_usage) */
|
|
t->stack[MTARCH_STACKSIZE - 29] = (unsigned char)((unsigned short)data) & 0xff;
|
|
t->stack[MTARCH_STACKSIZE - 30] = (unsigned char)((unsigned short)data >> 8) & 0xff;
|
|
|
|
/* Initialize stack pointer: Space for 2 2-byte-addresses and 32 registers,
|
|
* post-decrement POP / pre-increment PUSH scheme */
|
|
t->sp = &t->stack[MTARCH_STACKSIZE - 1 - 4 - 32];
|
|
}
|
|
|
|
/*--------------------------------------------------------------------------*/
|
|
static unsigned char *sptmp;
|
|
static struct mtarch_thread *running;
|
|
|
|
static void
|
|
sw(void)
|
|
{
|
|
/* Disable interrupts while we perform the context switch */
|
|
cli ();
|
|
|
|
/* Push 32 general purpuse registers */
|
|
__asm__("push r0");
|
|
__asm__("push r1");
|
|
__asm__("push r2");
|
|
__asm__("push r3");
|
|
__asm__("push r4");
|
|
__asm__("push r5");
|
|
__asm__("push r6");
|
|
__asm__("push r7");
|
|
__asm__("push r8");
|
|
__asm__("push r9");
|
|
__asm__("push r10");
|
|
__asm__("push r11");
|
|
__asm__("push r12");
|
|
__asm__("push r13");
|
|
__asm__("push r14");
|
|
__asm__("push r15");
|
|
__asm__("push r16");
|
|
__asm__("push r17");
|
|
__asm__("push r18");
|
|
__asm__("push r19");
|
|
__asm__("push r20");
|
|
__asm__("push r21");
|
|
__asm__("push r22");
|
|
__asm__("push r23");
|
|
__asm__("push r24");
|
|
__asm__("push r25");
|
|
__asm__("push r26");
|
|
__asm__("push r27");
|
|
__asm__("push r28");
|
|
__asm__("push r29");
|
|
__asm__("push r30");
|
|
__asm__("push r31");
|
|
|
|
/* Switch stack pointer */
|
|
sptmp = running->sp;
|
|
running->sp = (unsigned char*)SP;
|
|
SP = (unsigned short)sptmp;
|
|
|
|
/* Pop 32 general purpose registers */
|
|
__asm__("pop r31");
|
|
__asm__("pop r30");
|
|
__asm__("pop r29");
|
|
__asm__("pop r28");
|
|
__asm__("pop r27");
|
|
__asm__("pop r26");
|
|
__asm__("pop r25");
|
|
__asm__("pop r24");
|
|
__asm__("pop r23");
|
|
__asm__("pop r22");
|
|
__asm__("pop r21");
|
|
__asm__("pop r20");
|
|
__asm__("pop r19");
|
|
__asm__("pop r18");
|
|
__asm__("pop r17");
|
|
__asm__("pop r16");
|
|
__asm__("pop r15");
|
|
__asm__("pop r14");
|
|
__asm__("pop r13");
|
|
__asm__("pop r12");
|
|
__asm__("pop r11");
|
|
__asm__("pop r10");
|
|
__asm__("pop r9");
|
|
__asm__("pop r8");
|
|
__asm__("pop r7");
|
|
__asm__("pop r6");
|
|
__asm__("pop r5");
|
|
__asm__("pop r4");
|
|
__asm__("pop r3");
|
|
__asm__("pop r2");
|
|
__asm__("pop r1");
|
|
__asm__("pop r0");
|
|
|
|
/* Renable interrupts */
|
|
sei ();
|
|
}
|
|
/*--------------------------------------------------------------------------*/
|
|
void
|
|
mtarch_exec(struct mtarch_thread *t)
|
|
{
|
|
running = t;
|
|
sw();
|
|
running = NULL;
|
|
}
|
|
|
|
/*--------------------------------------------------------------------------*/
|
|
void
|
|
mtarch_remove(void)
|
|
{
|
|
|
|
}
|
|
/*--------------------------------------------------------------------------*/
|
|
void
|
|
mtarch_yield(void)
|
|
{
|
|
sw();
|
|
}
|
|
/*--------------------------------------------------------------------------*/
|
|
void
|
|
mtarch_pstop(void)
|
|
{
|
|
|
|
}
|
|
/*--------------------------------------------------------------------------*/
|
|
void
|
|
mtarch_pstart(void)
|
|
{
|
|
|
|
}
|
|
/*--------------------------------------------------------------------------*/
|
|
void
|
|
mtarch_stop(struct mtarch_thread *t)
|
|
{
|
|
|
|
}
|
|
/*--------------------------------------------------------------------------*/
|
|
int
|
|
mtarch_stack_usage(struct mt_thread *t)
|
|
{
|
|
uint8_t i;
|
|
for(i = 0; i < MTARCH_STACKSIZE; ++i) {
|
|
if(t->thread.stack[i] != i) {
|
|
break;
|
|
}
|
|
}
|
|
return MTARCH_STACKSIZE - i;
|
|
}
|
|
/*--------------------------------------------------------------------------*/
|