at91_cstartup.s79

uCOS-II for AT91M55800A完整实例

        
		cmp	r0,#0
		beq	after__segment_init

		mov	lr,r7
                bx      r6

		LTORG


        CPU_MODE
after__segment_init:

		REQUIRE	?jump_to_main

; Call the constructors of all global objects. This code will only
; be used if any EC++ modules defines global objects that need to
; have its constructor called before main.

#ifdef _ECPLUSPLUS

		RSEG	ICODE:CODE:NOROOT(2)

		PUBLIC	?call_ctors

		CPU_MODE
?call_ctors:
		ldr	r0,=SFB(DIFUNCT)		
		ldr	r1,=SFE(DIFUNCT)

                ldr     r4,=__call_ctors
                ldr     r5,=after__call_ctors
		mov	lr,r5
                bx      r4

		LTORG

		CPU_MODE
after__call_ctors:

#endif /* _ECPLUSPLUS */

; Jump to main, using BX. Set _exit as the return address.
; main may be located anywhere in memory, and be of
; either ARM or Thumb mode, since BX is used.
; main is assumed to return using BX (__interwork) if it is of
; a different mode than cstartup, otherwise it will return
; in the wrong mode, causing unpredicatble behaviour.

		RSEG	ICODE:CODE:NOROOT(2)
		PUBLIC	__main

		CPU_MODE
?jump_to_main:


               	LDR	r1,=INT_Vectors                     ; Pickup address of our vectors
        	MOV	r2,#0x4		       	            ; Pickup address of vector table
        	ldmia   r1!,{r4-r7}
        	stmia   r2!,{r4-r7}       

		ldr     r4,=main
                ldr     r5,=__main
		mov     r0,#0   ;  No parameters 
		mov	lr,r5        
		bx	r4

        CPU_MODE
__main:
?call_exit:
		ldr	r4,=exit
		ldr     r5,=_exit
		mov	lr,r5
		bx	r4
		LTORG
INT_Vectors:
	LDR     pc,Undef_Inst_Addr              ; Undefined Instruction
	LDR     pc,Software_Addr                ; Software Generated
	LDR     pc,Abort_Prefetch_Addr          ; Abort Prefetch
	LDR     pc,Abort_Data_Addr              ; Abort Data
	LDR     pc,Reserved_Addr                ; Reserved

Undef_Inst_Addr		DCD	INT_Undef_Inst
Software_Addr		DCD	INT_Software
Abort_Prefetch_Addr	DCD	INT_Abort_Prefetch
Abort_Data_Addr		DCD	INT_Abort_Data
Reserved_Addr		DCD	INT_Reserved  

	EXPORT  INT_Undef_Inst
INT_Undef_Inst
	B INT_Undef_Inst                        ; Undefined Instruction
;
	EXPORT  INT_Software
INT_Software
	B INT_Software                          ; Software Generated
;
	EXPORT  INT_Abort_Prefetch
INT_Abort_Prefetch
	B INT_Abort_Prefetch                    ; Abort Prefetch
;
	EXPORT  INT_Abort_Data
INT_Abort_Data
	B INT_Abort_Data                        ; Abort Data
;
	EXPORT  INT_Reserved
INT_Reserved
	B INT_Reserved                          ; Reserved
;

		LTORG
		ENDMOD


;---------------------------------------------------------------
; ?_EXIT
; main may return an exit code in R0, or _exit may be called with
; the exit code in R0.
; If the exit code is needed for som reason, R0 should be stored 
; in e.g. one of the registers R4-R7, so that the value is 
; preserved when calling __call_dtors and _Close_all.
;---------------------------------------------------------------
		MODULE	?_EXIT
		RSEG	LIB_SEGMENT:CODE:NOROOT(SEGMENT_ALIGN)
                PUBLIC  _exit
                REQUIRE ?jump_to_exit


		CPU_MODE		
_exit:
; Fall through to the next module


                RSEG	LIB_SEGMENT:CODE:NOROOT(SEGMENT_ALIGN)
                REQUIRE	?exit_restore
                PUBLIC	?exit_save

		CPU_MODE
?exit_save: 	
		mov		r7,r0

;---------------------------------------------------------------
; ?CALL_DTORS
; This module is only linked if needed by atexit.
;---------------------------------------------------------------

		RSEG	LIB_SEGMENT:CODE:NOROOT(SEGMENT_ALIGN)
		PUBLIC	__cstart_call_dtors
		REQUIRE	?exit_save

		CPU_MODE

; This label is required by "__record_needed_destruction".
__cstart_call_dtors:
                ldr     r4,?constants          ;  =__call_dtors
                ldr     r5,?constants+4        ;  =after__call_dtors
                mov	lr,r5
                bx      r4

after__call_dtors:

; Fall through to the next segment part


;---------------------------------------------------------------
; ?CALL_CLOSE
; This segment part is only linked if needed for closing files.
;---------------------------------------------------------------

		RSEG	LIB_SEGMENT:CODE:NOROOT(SEGMENT_ALIGN)
		PUBLIC	__cstart_closeall
		EXTERN	_Close_all
                REQUIRE ?exit_save

		CPU_MODE

; This label is required by functions operating on files
__cstart_closeall:
                ldr     r4,?constants+8        ;  =_Close_all
                ldr     r5,?constants+12       ;  =after_Close_all
                mov     lr,r5
                bx      r4

after_Close_all:        

; Fall through to the next segment part


;---------------------------------------------------------------
; ?_EXIT_END
; Restore the argument previously stored by the "save" section
; above.
;---------------------------------------------------------------

		RSEG        LIB_SEGMENT:CODE:NOROOT(SEGMENT_ALIGN)
		PUBLIC      ?exit_restore

		CPU_MODE

?exit_restore:
                mov	r0,r7

		;; Fall through to the __exit code below

;---------------------------------------------------------------
; ?JUMP_TO_EXIT
;---------------------------------------------------------------

		RSEG	LIB_SEGMENT:CODE:NOROOT(SEGMENT_ALIGN)
		PUBLIC	?jump_to_exit
		EXTERN	__exit

; It is not possible to fall through to __exit, because the following 
; module is only used when linking for debugging (XLINK -r).

?jump_to_exit:	

                ldr     r4,?constants+16        ;  =__exit
		mov	lr,r4
                bx      r4
        
        
       	        RSEG	LIB_SEGMENT:CODE:NOROOT(SEGMENT_ALIGN)
		EXTERN	__call_dtors
		EXTERN	_Close_all
		EXTERN	__exit

                DATA
?constants:     
                DC32    __call_dtors
		DC32	after__call_dtors
                DC32    _Close_all
		DC32	after_Close_all
                DC32    __exit
                
                ENDMOD


;---------------------------------------------------------------
; ?__EXIT
; __exit is declared PUBWEAK, which makes XLINK skip this module
; if another module containing a PUBLIC __exit is linked.
;---------------------------------------------------------------
		
		MODULE	?__EXIT
		RSEG	LIB_SEGMENT:CODE:NOROOT(2)
		PUBWEAK	__exit

		CPU_MODE		; Either Thumb or ARM mode
__exit

#ifdef __THUMB_LIBRARY__
		bx	pc
		nop
#endif

		CODE32		
		b	.		; Eternal loop

		ENDMOD


;---------------------------------------------------------------
; ?INITTAB
; This module is only linked if needed by e.g. __segment_init.
; The INITTAB segment contains segment initialization entries.
; See segment_init.h.
;---------------------------------------------------------------
		MODULE	?INITTAB
		RSEG	INITTAB:CONST(2)  ; Declaration for SFB/SFE below
		RSEG	HUGE_C:CONST:NOROOT(2)
		DATA
		PUBLIC	__segment_begin_INITTAB
		PUBLIC	__segment_end_INITTAB

__segment_begin_INITTAB	DC32	SFB(INITTAB)
__segment_end_INITTAB	DC32	SFE(INITTAB)

		ENDMOD

		END