rt-thread/libcpu/blackfin/bf53x/cpuport.c

94 lines
3.9 KiB
C

/*
* File : cpuport.c
* This file is part of RT-Thread RTOS
* COPYRIGHT (C) 2012, RT-Thread Development Team
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rt-thread.org/license/LICENSE
*
* Change Logs:
* Date Author Notes
* 2012-02-13 mojingxian first version
*/
#include <rtthread.h>
/* flag in interrupt handling */
rt_uint32_t rt_interrupt_from_thread;
rt_uint32_t rt_interrupt_to_thread;
rt_uint32_t rt_thread_switch_interrupt_flag;
/**
* initializes stack of thread
*/
rt_uint8_t *rt_hw_stack_init(void *tentry, void *parameter,
rt_uint8_t *stack_addr, void *texit)
{
unsigned char i;
unsigned long *stk;
stk = (unsigned long *)stack_addr; /* Load stack pointer */
/* Simulate a function call to the task with an argument */
stk -= 3; /* 3 words assigned for incoming args (R0, R1, R2) */
/* Now simulating vectoring to an ISR */
*--stk = (unsigned long)parameter; /* R0 value - caller's incoming argument #1 */
*--stk = (unsigned long)0; /* P1 value - value irrelevant */
*--stk = (unsigned long)texit; /* RETS value - NO task should return with RTS. */
/* however OS_CPU_Invalid_Task_Return is a safety */
/* catch-allfor tasks that return with an RTS */
*--stk = (unsigned long)parameter; /* R1 value - caller's incoming argument #2 */
/* (not relevant in current test example) */
*--stk = (unsigned long)parameter; /* R2 value - caller's incoming argument #3 */
/* (not relevant in current test example) */
*--stk = (unsigned long)0; /* P0 value - value irrelevant */
*--stk = (unsigned long)0; /* P2 value - value irrelevant */
*--stk = (unsigned long)0; /* ASTAT value - caller's ASTAT value - value */
/* irrelevant */
*--stk = (unsigned long)tentry; /* RETI value- pushing the start address of the task */
for (i = 0; i < 35; i++) /* remaining reg values - R7:3, P5:3, */
{ /* 4 words of A1:0(.W,.X), LT0, LT1, */
*--stk = (unsigned long)0; /* LC0, LC1, LB0, LB1,I3:0, M3:0, L3:0, B3:0, */
} /* All values irrelevant */
return (rt_uint8_t *)stk; /* Return top-of-stack */
}
void rt_hw_context_switch(rt_uint32_t from, rt_uint32_t to)
{
if (rt_thread_switch_interrupt_flag != 1)
{
rt_thread_switch_interrupt_flag = 1;
rt_interrupt_from_thread = from;
}
rt_interrupt_to_thread = to;
asm("raise 14;"); // Raise Interrupt 14 (trap)
}
void rt_hw_context_switch_interrupt(rt_uint32_t from, rt_uint32_t to)
{
if (rt_thread_switch_interrupt_flag != 1)
{
rt_thread_switch_interrupt_flag = 1;
rt_interrupt_from_thread = from;
}
rt_interrupt_to_thread = to;
asm("raise 14;"); // Raise Interrupt 14 (trap)
}
void rt_hw_context_switch_to(rt_uint32_t to)
{
rt_thread_switch_interrupt_flag = 1;
rt_interrupt_from_thread = 0;
rt_interrupt_to_thread = to;
asm("raise 14;"); // Raise Interrupt 14 (trap)
}