/* * 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) }