syscall.s

一个小型的嵌入式操作系统内核,可用于多种硬件平台

;**************************************************************************************************
;                                      EDL RTOS Kernel
;                              (c) Copyright 2005, Wu Jun
;                                   All Rights Reserved    
;                For further information, please visit http://www.enjoydigitallife.com
;
; Description:      None
; History:          
;    Date                         Remarks
;    2005-01-06                   Created initial version
;    2005-12-12                   Finished the version 2.01
;**************************************************************************************************


    EXPORT  edl_createTask
    EXPORT  edl_deleteTask
    EXPORT  edl_suspendTask
    EXPORT  edl_resumeTask    
    EXPORT  edl_sleep
    EXPORT  edl_wakeTask
    EXPORT  edl_sendEvent
    EXPORT  edl_getEvent
    EXPORT  edl_trunkAlloc
    EXPORT  edl_trunkFree
    EXPORT  edl_heapCreate
    EXPORT  edl_heapDelete
    EXPORT  edl_heapAlloc
    EXPORT  edl_heapFree
    EXPORT  edl_heapReAlloc
    EXPORT  edl_createSem
    EXPORT  edl_deleteSem
    EXPORT  edl_getSem
    EXPORT  edl_releaseSem
    EXPORT  edl_sendMsg
    EXPORT  edl_getMsg
    EXPORT  edl_createMutex
    EXPORT  edl_deleteMutex
    EXPORT  edl_getMutex
    EXPORT  edl_releaseMutex


    CODE32
    AREA    SYSTEM_CALLS, CODE,READONLY
;/**************************************************************************************************
;* Description:      create a task
;* Parameters:       tskProc             pointer to task's starting code
;                    pdata               Pointer to a data block which could be used by task's
;                                        routine
;                    prio                task's priority, start at 1
;                    stackSize           Specifies the stack size in unit of word( 4 bytes ).
;                    tskMode             Specifies the task mode
;                                        TSK_MODE_SYS            For kernel task
;                                        TSK_MODE_USR            For user task
;                    tskID               pointer to a U32 type variable to store task's ID
;* return values:    ERR_INVALID_PRIO            Invalid priority
;                    ERR_INVALID_STACK_SIZE      Invalid stack size
;                    ERR_ALLOC_STACK_FAIL        Failed to allocate stack
;                    ERR_ALLOC_TCB_FAIL          No TCB is available
;                    ERR_OUT_OF_TASK_MAX_NUM     Out of max task number
;                    ERR_SUCCESS                 OK
;**************************************************************************************************/
edl_createTask
    STMFD   SP!, {R4,R5}    ; Save the registers modified in the function
    add     r5,sp,#8        
    LDMFD   r5, {R4}        ; Get the fifth parameter from stack and assign it to r4 as the fifth 
                            ; parameter in system call
    swi 0                   ; Software interrupt
    LDMFD   SP!, {R4,R5}    ; Restore the registers modified in the function
    mov pc,lr


;/**************************************************************************************************
;* Description:      Delete a task
;* Parameters:       r0                     Specifies the task's ID to be deleted
;* return values:    ERR_INVALID_TSK_ID          Invalid task ID
;                    ERR_SUCCESS                 OK
;**************************************************************************************************/
edl_deleteTask
    swi 1
    mov pc,lr



;/**************************************************************************************************
;* Description:      Suspend a task
;* Parameters:       r0             Specifies the task's ID to be suspended
;* Return values:    ERR_INVALID_PARAM       Invalid parameters
;                    ERR_SUCCESS             OK         
;                    ERR_TASK_SUSPENDED      The specified task has already been suspended.
;* Notes:            This function is externally called to block a task.
;**************************************************************************************************/
edl_suspendTask
    swi 2
    mov pc,lr

;/**************************************************************************************************
;* Description:      Resume a task
;* Parameters:       r0             Specifies the task's ID to be suspended
;* Return values:    ERR_INVALID_PARAM       Invalid parameters
;                    ERR_SUCCESS             OK         
;                    ERR_TASK_READY          The specified task has already been ready.
;                    ERR_TSK_STATUS_ERROR    The task to be resumed is not in the specified status.
;* Notes:            This function is externally called to resume a task.
;**************************************************************************************************/
edl_resumeTask
    swi 3
    mov pc,lr

;/**************************************************************************************************
;* Description:      sleep for a period of time
;* Parameters:       r0             specify how long the task  should sleep, in unit of timer 
;                                        tick
;**************************************************************************************************/
edl_sleep
    swi 4
    mov pc,lr

;/**************************************************************************************************
;* Description:      wake up a task
;* Parameters:       tskID                   Specifies the task's ID to be woken up.
;* Notes:            This function is designed for user task
;**************************************************************************************************/
edl_wakeTask
    swi 5
    mov pc,lr


;/**************************************************************************************************
;* Description:      Send events to a specified task
;* Parameters:       tskID               task ID
;                    event               bitmaped events to be sent
;* return values:    ERR_INVALID_EVENT       invalid event
;                    ERR_SUCCESS             OK
;**************************************************************************************************/
edl_sendEvent
    swi 6
    mov pc,lr

;/**************************************************************************************************
;* Description:      Receive events
;* Parameters:       timeOut                wait time in unit of timer tick, 
;                                            If wait time is 0, this function just peeks at the event
;                                            buffer, if events arrived,it gets it and go back,otherwise
;                                            just return.
;                                            Else if wait time is INFINITE_TIME(0xffffffff), the task 
;                                            does not wake up until the events arrive.
;                                            Else sleep for a period of time to wait for the wanted events.
;                    evMask                  event mask specifying the wanted events.
;                    waitAll                 specify whether the task need to get all events
;                                            TRUE        this function returns only when all events arrive
;                                            FALSE       as long as events arrive, this function returns.
;                    event                   a pointer to a data structure of type U32.
;* Return values:    ERR_INVALID_PARAM       invalid parameter.
;                    ERR_NO_EVENT            No event
;                    ERR_SUCCESS             OK.
;                    ERR_TIMEOUT             time is out
;**************************************************************************************************/
edl_getEvent
    swi 7
    mov pc,lr

;/**************************************************************************************************
;* Description:      Allocate a trunk of memory block.
;* Parameters:       zone_id         Specifies the zone ID where the free page would be allocated
;                    size     Specifies the block size to allocate, if its value is zero,
;                                    then system allocate the max free block in the zone.
;* Return Values:    Allocated address
;* Note(s):          This function is only called by user application through system call
;**************************************************************************************************/
edl_trunkAlloc
    swi 8
    mov pc,lr

;/**************************************************************************************************
;* Description:      Free a trunk of memory block.
;* Parameters:       addr        The block's start address
;* return values:    ERR_INVALID_PARAM       Invalid parameter
;                    ERR_SUCCESS             OK
;* Note(s):          This function is only called by user application through system call                    
;**************************************************************************************************/
edl_trunkFree
    swi 9
    mov pc,lr

;/**************************************************************************************************
;* Description:      Create a heap.
;* Parameters:       start           Heap's start address 
;                    heapSize        Specifies the heap size in unit of byte
;                    unitSize        Specifies the unit size in unit of byte. Each allocated memory
;                                    block is composed by these unit
;                    maxUnitNbr      Specifies the max number of unit the heap could allocate
;                    heapID          Pointer to a variable to stores the heap ID
;* return values:    ERR_INVALID_PARAM       Invalid parameter
;                    ERR_OUT_OF_MEM_MAX_NUM  No heap control block is available
;                    ERR_SUCCESS             OK
;**************************************************************************************************/
edl_heapCreate
    STMFD   SP!, {R4,R5}    ; Save the registers modified in the function
    add     r5,sp,#8        
    LDMFD   r5, {R4}        ; Get the fifth parameter from stack and assign it to r4 as the fifth 
                            ; parameter in system call
    swi 10                   ; Software interrupt
    LDMFD   SP!, {R4,R5}    ; Restore the registers modified in the function
    mov pc,lr

;/**************************************************************************************************
;* Description:      Destroy a heap.
;* Parameters:       heapID      Specifies the heap ID
;* return values:    ERR_INVALID_PARAM       Invalid parameter
;                    ERR_SUCCESS             OK
;**************************************************************************************************/
edl_heapDelete