os_cpu_c.c

ucOS2 for AT91SAM7S64,KEIL环境

/*
*********************************************************************************************************
*                                               uC/OS-II
*                                         The Real-Time Kernel
*
*                        (c) Copyright 1992-1998, Jean J. Labrosse, Plantation, FL
*                                          All Rights Reserved
*                        (c) Copyright ARM Limited 1999.  All rights reserved.
*
*                                          ARM Specific code
*
*
* File : OS_CPU_C.C
*********************************************************************************************************
*/

#define  OS_CPU_GLOBALS 

#include "includes.h"
#include "os_cpu.h"
#include "os_cfg.h"

/*
*********************************************************************************************************
*                                        INITIALIZE A TASK'S STACK
*
* Description: This function is called by either OSTaskCreate() or OSTaskCreateExt() to initialize the
*              stack frame of the task being created.  This function is highly processor specific.
*
* Arguments  : task          is a pointer to the task code
*
*              pdata         is a pointer to a user supplied data area that will be passed to the task
*                            when the task first executes.
*
*              ptos          is a pointer to the top of stack.  It is assumed that 'ptos' points to
*                            a 'free' entry on the task stack.  If OS_STK_GROWTH is set to 1 then 
*                            'ptos' will contain the HIGHEST valid address of the stack.  Similarly, if
*                            OS_STK_GROWTH is set to 0, the 'ptos' will contains the LOWEST valid address
*                            of the stack.
*
*              opt           specifies options that can be used to alter the behavior of OSTaskStkInit().
*                            (see uCOS_II.H for OS_TASK_OPT_???).
*
* Returns    : Always returns the location of the new top-of-stack' once the processor registers have
*              been placed on the stack in the proper order.
*
* Note(s)    : Interrupts are enabled when your task starts executing. You can change this by setting the
*              PSW to 0x0002 instead.  In this case, interrupts would be disabled upon task startup.  The
*              application code would be responsible for enabling interrupts at the beginning of the task
*              code.  You will need to modify OSTaskIdle() and OSTaskStat() so that they enable 
*              interrupts.  Failure to do this will make your system crash!
*********************************************************************************************************/


OS_STK * OSTaskStkInit (void (*task)(void *pd), void *pdata, OS_STK *ptos, INT16U opt)
{
    OS_STK *stk;
    opt    = opt;                           /* 'opt' is not used, prevent warning                      */
    stk    = ptos;                          /* Load stack pointer                                      */

    /* build a context for the new task */
    *--stk = (unsigned int) task;         /* pc */
    *--stk = (unsigned int) task;         /* lr */
                                            /* SP */
    *--stk = 0x12;                         /* r12 */
    *--stk = 0x11;                         /* r11 */
    *--stk = 0x10;                         /* r10 */
    *--stk = 0x09;                         /* r9  */
    *--stk = 0x08;                         /* r8  */
    *--stk = 0x07;                         /* r7  */
    *--stk = 0x06;                         /* r6  */
    *--stk = 0x05;                         /* r5  */
    *--stk = 0x04;                         /* r4  */
    *--stk = 0x03;                         /* r3  */
    *--stk = 0x02;                         /* r2  */
    *--stk = 0x01;                         /* r1  */
    *--stk = (unsigned int) pdata;       /* r0  */
    *--stk = (0x1f|0x00);			       /* cpsr  Sys mode FIQ IRQ Enable*/
    *--stk = (0x1f|0x00);			       /* spsr  Sys mode FIQ IRQ enable */
    
    //这是标准的栈结构
    
    return stk;
}

/*$PAGE*/
#if OS_CPU_HOOKS_EN
/*
*********************************************************************************************************
*                                          TASK CREATION HOOK
*
* Description: This function is called when a task is created.
*
* Arguments  : ptcb   is a pointer to the task control block of the task being created.
*
* Note(s)    : 1) Interrupts are disabled during this call.
*********************************************************************************************************
*/
void OSTaskCreateHook (OS_TCB *ptcb)
{
    ptcb = ptcb;                       /* Prevent compiler warning                                     */
}


/*
*********************************************************************************************************
*                                           TASK DELETION HOOK
*
* Description: This function is called when a task is deleted.
*
* Arguments  : ptcb   is a pointer to the task control block of the task being deleted.
*
* Note(s)    : 1) Interrupts are disabled during this call.
*********************************************************************************************************
*/
void OSTaskDelHook (OS_TCB *ptcb)
{
    ptcb = ptcb;                       /* Prevent compiler warning                                     */
}

/*
*********************************************************************************************************
*                                           TASK SWITCH HOOK
*
* Description: This function is called when a task switch is performed.  This allows you to perform other
*              operations during a context switch.
*
* Arguments  : none
*
* Note(s)    : 1) Interrupts are disabled during this call.
*              2) It is assumed that the global pointer 'OSTCBHighRdy' points to the TCB of the task that
*                 will be 'switched in' (i.e. the highest priority task) and, 'OSTCBCur' points to the 
*                 task being switched out (i.e. the preempted task).
*********************************************************************************************************
*/
void OSTaskSwHook (void)
{
 //uprintf("\nTaskSw\n");
}

/*
*********************************************************************************************************
*                                           STATISTIC TASK HOOK
*
* Description: This function is called every second by uC/OS-II's statistics task.  This allows your 
*              application to add functionality to the statistics task.
*
* Arguments  : none
*********************************************************************************************************
*/
void OSTaskStatHook (void)
{
 //unsigned char xx=0;
 //xx=100-100*OSIdleCtr/OSIdleCtrMax;
 //uprintf("OSIdleCtr=%d\n",OSIdleCtr);
 //uprintf("OSIdleCtrMax=%d\n",OSIdleCtrMax);
 //uprintf("CPUusage=%3d%%\n",OSCPUUsage);
}

/*
*********************************************************************************************************
*                                               TICK HOOK
*
* Description: This function is called every tick.
*
* Arguments  : none
*
* Note(s)    : 1) Interrupts may or may not be ENABLED during this call.
*********************************************************************************************************
*/

void OSTimeTickHook (void)
{
  //uprintf("\nvoid OSTimeTickHook (void)  ");
  //uprintf("   %d\n",tt);
}
#endif


void OSInitHookBegin (void)
{
	//uprintf ( "OSInitHookBegin(void)\n" );
}


void OSInitHookEnd (void)
{
	//uprintf ( "OSInitHookEnd(void)\n" );
}


void OSTaskIdleHook (void)
{

 //uprintf("\nOSTaskIdleHook\n");
}



void OSTCBInitHook (OS_TCB *ptcb)
{
        
}