os_cpu_c.c

tms320c6201下的UCOS

/*
*********************************************************************************************************
*                                               uC/OS-II
*                                         The Real-Time Kernel
*
*                        (c) Copyright 1992-1998, Jean J. Labrosse, Plantation, FL
*                                          All Rights Reserved
*
*
*                                       Texas Instruments TMSC6201 Specific code
*                                          SMALL MEMORY MODEL
*
* File : OS_CPU_C.C
* By   : Jean J. Labrosse
*********************************************************************************************************
*/

#define  OS_CPU_GLOBALS
#include "includes.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!
*********************************************************************************************************
*/
void       *OSTaskStkInit(void (*task)(void *pd), void *pdata, void *ptos, INT16U opt)
{
    INITIAL_REGISTER_FRAME   *Frame, *StackBottom;
    int *FirstFreeCellInStack ;
   /*------------------------------------------------------------------------
      THE SP MUST BE ALIGNED ON AN 8-BYTE BOUNDARY.                          
      The FRAME must be an alignment of that also
   
    ------------------------------------------------------------------------*/
       
       Frame =  (INITIAL_REGISTER_FRAME   *)  ((int)ptos &~7 );               
       StackBottom  = Frame ;
       Frame-- ;  /* go to ok position */

       
       Frame->A0.integer   =   0x0A0      ;
       Frame->A1.integer   =   0x0A1      ;
       Frame->A2.integer   =   0x0A2      ;
       Frame->A3.integer   =   0x0A3      ;
       Frame->A4.integer = (int) pdata       ; /* data pointer first argument */
       Frame->A5.integer   =   0x0A5      ;
       Frame->A6.integer   =   0x0A6      ;
       Frame->A7.integer   =   0x0A7      ;
       Frame->A8.integer   =   0x0A8      ;
       Frame->A9.integer   =   0x0A9      ;
       Frame->A10.integer  =   0x0A10     ;
       Frame->A11.integer  =   0x0A11     ;
       Frame->A12.integer  =   0x0A12     ;
       Frame->A13.integer  =   0x0A13     ;
       Frame->A14.integer  =   0x0A14     ;
       Frame->A15.integer  =   0xA15      ;
       Frame->B0.integer   =   0x0B0      ;
       Frame->B1.integer   =   0x0B1      ;
       Frame->B2.integer   =   0x0B2      ;
       Frame->B3.integer   =   0x0B3      ;
       Frame->B4.integer   =   0x0B4      ;
       Frame->B5.integer   =   0x0B5      ;
       Frame->B6.integer   =   0x0B6      ;
       Frame->B7.integer   =   0x0B7      ;
       Frame->B8.integer   =   0x0B8      ;
       Frame->B9.integer   =   0x0B9      ;
       Frame->B10.integer  =   0x0B10     ;
       Frame->B11.integer  =   0x0B11     ;
       Frame->B12.integer  =   0x0B12     ;
       Frame->B13.integer  =   0x0B13     ;
   /*------------------------------------------------------------------------
      PASS THE CURRENT DP TO THE task
     ------------------------------------------------------------------------*/
       Frame->B14.integer = ReturnCurrentDP(  )  ;  /* data pointer */
       Frame->B15.integer= (int) StackBottom  ; /* C env Frame pointer */
       
       
       /*
          Enable interrupts disabled
        */
        
        Frame->AMR_Adressing_Mode_Register   = 0 ;
        
        /* Endian bit : Big endian */
        /* Program Cache disabled ( 2 << 5 ) */
        /* Data Cache disabled    ( 2 << 2 ) */
        /* PGIE set */
        /* When most of the application is in internal program memory, do not use the cache */
        Frame->CSR_Control_Status_Register   = (0<<8) + /*(2<<5) + (2<<2)*/ + 3 ;    		
        
        /* Set NMIE bit : bit 1 in IER */
        Frame->IER_Interrupt_Enable_Register = Normally_Enabled_Interrupts ;
        Frame->IRP_Interrupt_Return_Pointer  = 0xdeadbeef ;   	 	
        Frame->Start_Address                 = task ;
        
        FirstFreeCellInStack  =( int*) Frame ;
        FirstFreeCellInStack--;

        return (FirstFreeCellInStack);
}


/*$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)
{
}

/*
*********************************************************************************************************
*                                           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)
{
}

/*
*********************************************************************************************************
*                                               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)
{
}
#endif