a_misc.c

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/*
===============================================================================
| Copyright (C) 2004 RuanHaiShen, All rights reserved.
| SUMMARY: 
|   Miscellaneous functions.
|
| DESCRIPTION:
|   See http://www.01s.org for documentation, latest information, license 
|   and contact details.
|   email:[e-mail]
=============================================================================*/
/*===========================================================================*/
#include "arch/arch.h"
#include "inc/queue.h"
#include "inc/kernel.h"
#include "inc/memory.h"
#include "inc/ipc.h"
#include "inc/kapi.h"

extern u32      _task_init_bkp;

struct reg_context
{
    u32  bkp;
    u16  ds;
    u16  flags;
    u32  pc;
    u32  exit;
    u32  arg;
    u16  earg;
};

u8* __stack_init(entry_t entry, arg_t arg, sp_t ptos)
{
    struct reg_context* regs;

    regs = (struct reg_context*)
        ((u32)ptos - sizeof(struct reg_context));

    regs->bkp    = (u32)&_task_init_bkp;
    regs->ds     = _DS;
    regs->flags  = (u16)0x0202;
    regs->pc     = (u32)entry;
#if CFG_TASK_DEL_EN > 0
    regs->exit   = (u32)task_delete;
#endif
    regs->arg    = (u32)arg;
    regs->earg   = (u16)0xffff;

    return  (u8*)regs;
}

extern u8 _dos_tick_counter;
void __timer_interrupt()
{
    register u8 flag;
    
    __intr_enter();
    
    if (--_dos_tick_counter == 0) {
        _dos_tick_counter = 11;
        __dos_tick();
    } else {
        __eoi_to_8259a();
    }
    flag = __do_tick();
    __intr_exit(flag);
}



/*===========================================================================*/