/*
*********************************************************************************************************
*                                                uC/OS-II
*                                          The Real-Time Kernel
*
*
*                           (c) Copyright 2009-2010; Micrium, Inc.; Weston, FL
*                    All rights reserved.  Protected by international copyright laws.
*
*                                           ARM Cortex-M4 Port
*
* File      : OS_CPU_C.C
* Version   : V2.92
* By        : JJL
*             BAN
*
* LICENSING TERMS:
* ---------------
*             uC/OS-III is provided in source form to registered licensees ONLY.  It is
*             illegal to distribute this source code to any third party unless you receive
*             written permission by an authorized Micrium representative.  Knowledge of
*             the source code may NOT be used to develop a similar product.
*
*             Please help us continue to provide the Embedded community with the finest
*             software available.  Your honesty is greatly appreciated.
*
*             You can contact us at www.micrium.com.
*
* For       : ARMv7 Cortex-M4
* Mode      : Thumb-2 ISA
* Toolchain : IAR EWARM
*********************************************************************************************************
*/

#define   OS_CPU_GLOBALS

#ifdef VSC_INCLUDE_SOURCE_FILE_NAMES
const  CPU_CHAR  *os_cpu_c__c = "$Id: $";
#endif

/*$PAGE*/
/*
*********************************************************************************************************
*                                             INCLUDE FILES
*********************************************************************************************************
*/

#include  <ucos_ii.h>
//#include  <lib_def.h>  //这个是ucos官方自带的外设标准C库的头文件  ，我们这里不用，所以需要添加其包含的宏定义


//--------------------------------------------------------------------------------------------------------------------------
//                                                 uclib的一些定义
//                                                                                                    —— by 野火嵌入式开发

//<lib_def.h>包含的宏定义
#define  DEF_BIT_FIELD(bit_field, bit_shift)         ((((bit_field) >= DEF_INT_CPU_NBR_BITS) ? (DEF_INT_CPU_U_MAX_VAL)     \
                                                                                             : (DEF_BIT(bit_field) - 1uL)) \
                                                                                                    << (bit_shift))

#define  DEF_INT_CPU_NBR_BITS                           (CPU_CFG_DATA_SIZE * DEF_OCTET_NBR_BITS)
#define  DEF_INT_CPU_U_MAX_VAL                           DEF_INT_32U_MAX_VAL
#define  DEF_BIT(bit)                           (1uL << (bit))


#define  DEF_OCTET_NBR_BITS                                8

#define  DEF_INT_32U_MAX_VAL                      4294967295uL


#define  DEF_BIT_MASK(bit_mask, bit_shift)             ((bit_mask) << (bit_shift))





//<lib_def.h>包含的宏定义需要用到<cpu.h>所包含的宏定义
#define  CPU_CFG_DATA_SIZE              CPU_WORD_SIZE_32        /* Defines CPU data    word size  (in octets).          */


//<lib_def.h>包含的宏定义需要用到<cpu_def.h>所包含的宏定义
#define  CPU_WORD_SIZE_32                          4u   /* 32-bit word size (in octets).                                */


//--------------------------------------------------------------------------------------------------------------------------



/*
*********************************************************************************************************
*                                          LOCAL VARIABLES
*********************************************************************************************************
*/

#if OS_TMR_EN > 0u
static  INT16U  OSTmrCtr;
#endif

/*
*********************************************************************************************************
*                                          SYS TICK DEFINES
*********************************************************************************************************
*/

#define  OS_CPU_CM3_NVIC_ST_CTRL    (*((volatile INT32U *)0xE000E010uL)) /* SysTick Ctrl & Status Reg. */
#define  OS_CPU_CM3_NVIC_ST_RELOAD  (*((volatile INT32U *)0xE000E014uL)) /* SysTick Reload  Value Reg. */
#define  OS_CPU_CM3_NVIC_ST_CURRENT (*((volatile INT32U *)0xE000E018uL)) /* SysTick Current Value Reg. */
#define  OS_CPU_CM3_NVIC_ST_CAL     (*((volatile INT32U *)0xE000E01CuL)) /* SysTick Cal     Value Reg. */
#define  OS_CPU_CM3_NVIC_SHPRI1     (*((volatile INT32U *)0xE000ED18uL)) /* System Handlers  4 to  7 Prio.       */
#define  OS_CPU_CM3_NVIC_SHPRI2     (*((volatile INT32U *)0xE000ED1CuL)) /* System Handlers  8 to 11 Prio.       */
#define  OS_CPU_CM3_NVIC_SHPRI3     (*((volatile INT32U *)0xE000ED20uL)) /* System Handlers 12 to 15 Prio.       */


#define  OS_CPU_CM3_NVIC_ST_CTRL_COUNT                    0x00010000uL   /* Count flag.                */
#define  OS_CPU_CM3_NVIC_ST_CTRL_CLK_SRC                  0x00000004uL   /* Clock Source.              */
#define  OS_CPU_CM3_NVIC_ST_CTRL_INTEN                    0x00000002uL   /* Interrupt enable.          */
#define  OS_CPU_CM3_NVIC_ST_CTRL_ENABLE                   0x00000001uL   /* Counter mode.              */
#define  OS_CPU_CM3_NVIC_PRIO_MIN                               0xFFu    /* Min handler prio.          */

/*
*********************************************************************************************************
*                                       OS INITIALIZATION HOOK
*                                            (BEGINNING)
*
* Description: This function is called by OSInit() at the beginning of OSInit().
*
* Arguments  : none
*
* Note(s)    : 1) Interrupts should be disabled during this call.
*********************************************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0u
void  OSInitHookBegin (void)
{
    INT32U   size;
    OS_STK  *pstk;

    /* Clear exception stack for stack checking.*/
    pstk = &OS_CPU_ExceptStk[0];
    size = OS_CPU_EXCEPT_STK_SIZE;
    while (size > 0u)
    {
        size--;
        *pstk++ = (OS_STK)0;
    }

    OS_CPU_ExceptStkBase = &OS_CPU_ExceptStk[OS_CPU_EXCEPT_STK_SIZE - 1u];

#if OS_TMR_EN > 0u
    OSTmrCtr = 0u;
#endif
}
#endif


/*
*********************************************************************************************************
*                                       OS INITIALIZATION HOOK
*                                               (END)
*
* Description: This function is called by OSInit() at the end of OSInit().
*
* Arguments  : none
*
* Note(s)    : 1) Interrupts should be disabled during this call.
*********************************************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0u
void  OSInitHookEnd (void)
{
}
#endif


/*
*********************************************************************************************************
*                                          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.
*********************************************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0u
void  OSTaskCreateHook (OS_TCB *ptcb)
{
#if OS_APP_HOOKS_EN > 0u
    App_TaskCreateHook(ptcb);
#else
    (void)ptcb;                                  /* Prevent compiler warning                           */
#endif
}
#endif


/*
*********************************************************************************************************
*                                           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.
*********************************************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0u
void  OSTaskDelHook (OS_TCB *ptcb)
{
#if OS_APP_HOOKS_EN > 0u
    App_TaskDelHook(ptcb);
#else
    (void)ptcb;                                  /* Prevent compiler warning                           */
#endif
}
#endif


/*
*********************************************************************************************************
*                                             IDLE TASK HOOK
*
* Description: This function is called by the idle task.  This hook has been added to allow you to do
*              such things as STOP the CPU to conserve power.
*
* Arguments  : none
*
* Note(s)    : 1) Interrupts are enabled during this call.
*********************************************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0u
void  OSTaskIdleHook (void)
{
#if OS_APP_HOOKS_EN > 0u
    App_TaskIdleHook();
#endif
}
#endif

/*
*********************************************************************************************************
*                                            TASK RETURN HOOK
*
* Description: This function is called if a task accidentally returns.  In other words, a task should
*              either be an infinite loop or delete itself when done.
*
* Arguments  : ptcb      is a pointer to the task control block of the task that is returning.
*
* Note(s)    : none
*********************************************************************************************************
*/

#if OS_CPU_HOOKS_EN > 0u
void  OSTaskReturnHook (OS_TCB  *ptcb)
{
#if OS_APP_HOOKS_EN > 0u
    App_TaskReturnHook(ptcb);
#else
    (void)ptcb;
#endif
}
#endif


/*
*********************************************************************************************************
*                                           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
*********************************************************************************************************
*/

#if OS_CPU_HOOKS_EN > 0u
void  OSTaskStatHook (void)
{
#if OS_APP_HOOKS_EN > 0u
    App_TaskStatHook();
#endif
}
#endif

/*
*********************************************************************************************************
*                                        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
*
*              p_arg         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_xxx).
*
* 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)    : 1) Interrupts are enabled when your task starts executing.
*              2) All tasks run in Thread mode, using process stack.
*********************************************************************************************************
*/

OS_STK *OSTaskStkInit (void (*task)(void *p_arg), void *p_arg, OS_STK *ptos, INT16U opt)
{
    OS_STK *stk;


    (void)opt;                                   /* 'opt' is not used, prevent warning                 */
    stk       = ptos;                            /* Load stack pointer                                 */

    /* Registers stacked as if auto-saved on exception    */
    *(stk)    = (INT32U)0x01000000uL;            /* xPSR                                               */
    *(--stk)  = (INT32U)task;                    /* Entry Point                                        */
    *(--stk)  = (INT32U)OS_TaskReturn;           /* R14 (LR)                                           */
    *(--stk)  = (INT32U)0x12121212uL;            /* R12                                                */
    *(--stk)  = (INT32U)0x03030303uL;            /* R3                                                 */
    *(--stk)  = (INT32U)0x02020202uL;            /* R2                                                 */
    *(--stk)  = (INT32U)0x01010101uL;            /* R1                                                 */
    *(--stk)  = (INT32U)p_arg;                   /* R0 : argument                                      */

    /* Remaining registers saved on process stack         */
    *(--stk)  = (INT32U)0x11111111uL;            /* R11                                                */
    *(--stk)  = (INT32U)0x10101010uL;            /* R10                                                */
    *(--stk)  = (INT32U)0x09090909uL;            /* R9                                                 */
    *(--stk)  = (INT32U)0x08080808uL;            /* R8                                                 */
    *(--stk)  = (INT32U)0x07070707uL;            /* R7                                                 */
    *(--stk)  = (INT32U)0x06060606uL;            /* R6                                                 */
    *(--stk)  = (INT32U)0x05050505uL;            /* R5                                                 */
    *(--stk)  = (INT32U)0x04040404uL;            /* R4                                                 */

    return (stk);
}


/*
*********************************************************************************************************
*                                           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).
*********************************************************************************************************
*/
#if (OS_CPU_HOOKS_EN > 0u) && (OS_TASK_SW_HOOK_EN > 0u)
void  OSTaskSwHook (void)
{
#if OS_APP_HOOKS_EN > 0u
    App_TaskSwHook();
#endif
}
#endif


/*
*********************************************************************************************************
*                                           OS_TCBInit() HOOK
*
* Description: This function is called by OS_TCBInit() after setting up most of the TCB.
*
* Arguments  : ptcb    is a pointer to the TCB of the task being created.
*
* Note(s)    : 1) Interrupts may or may not be ENABLED during this call.
*********************************************************************************************************
*/
#if OS_CPU_HOOKS_EN > 0u
void  OSTCBInitHook (OS_TCB *ptcb)
{
#if OS_APP_HOOKS_EN > 0u
    App_TCBInitHook(ptcb);
#else
    (void)ptcb;                                  /* Prevent compiler warning                           */
#endif
}
#endif


/*
*********************************************************************************************************
*                                               TICK HOOK
*
* Description: This function is called every tick.
*
* Arguments  : none
*
* Note(s)    : 1) Interrupts may or may not be ENABLED during this call.
*********************************************************************************************************
*/
#if (OS_CPU_HOOKS_EN > 0u) && (OS_TIME_TICK_HOOK_EN > 0u)
void  OSTimeTickHook (void)
{
#if OS_APP_HOOKS_EN > 0u
    App_TimeTickHook();
#endif

#if OS_TMR_EN > 0u
    OSTmrCtr++;
    if (OSTmrCtr >= (OS_TICKS_PER_SEC / OS_TMR_CFG_TICKS_PER_SEC))
    {
        OSTmrCtr = 0;
        OSTmrSignal();
    }
#endif
}
#endif


/*$PAGE*/
/*
*********************************************************************************************************
*                                          SYS TICK HANDLER
*
* Description: Handle the system tick (SysTick) interrupt, which is used to generate the uC/OS-II tick
*              interrupt.
*
* Arguments  : None.
*
* Note(s)    : 1) This function MUST be placed on entry 15 of the Cortex-M3 vector table.
*********************************************************************************************************
*/

void  OS_CPU_SysTickHandler (void)
{
    OS_CPU_SR  cpu_sr;


    OS_ENTER_CRITICAL();                         /* Tell uC/OS-II that we are starting an ISR          */
    OSIntNesting++;
    OS_EXIT_CRITICAL();

    OSTimeTick();                                /* Call uC/OS-II's OSTimeTick()                       */

    OSIntExit();                                 /* Tell uC/OS-II that we are leaving the ISR          */
}


/*$PAGE*/
/*
*********************************************************************************************************
*                                         INITIALIZE SYS TICK
*
* Description: Initialize the SysTick.
*
* Arguments  : cnts         Number of SysTick counts between two OS tick interrupts.
*
* Note(s)    : 1) This function MUST be called after OSStart() & after processor initialization.
*********************************************************************************************************
*/

void  OS_CPU_SysTickInit (INT32U  cnts)
{
    INT32U  prio;


    OS_CPU_CM3_NVIC_ST_RELOAD = cnts - 1u;

    /* Set SysTick handler prio.                              */
    prio  = OS_CPU_CM3_NVIC_SHPRI3;
    prio &= DEF_BIT_FIELD(24, 0);
    prio |= DEF_BIT_MASK(OS_CPU_CFG_SYSTICK_PRIO, 24);

    OS_CPU_CM3_NVIC_SHPRI3 = prio;

    /* Enable timer.                                          */
    OS_CPU_CM3_NVIC_ST_CTRL |= OS_CPU_CM3_NVIC_ST_CTRL_CLK_SRC |
                               OS_CPU_CM3_NVIC_ST_CTRL_ENABLE;
    /* Enable timer interrupt.                                */
    OS_CPU_CM3_NVIC_ST_CTRL |= OS_CPU_CM3_NVIC_ST_CTRL_INTEN;
}

