44binit.s

杭州立宇泰豪华型44B0开发板

; *******************************************************
; * NAME    : 44BINIT.S									*
; * Version : 10.April.2000								*
; * Description:										*
; *	C start up codes									*
; *	Configure memory, Initialize ISR ,stacks			*
; *	Initialize C-variables								*
; *	Fill zeros into zero-initialized C-variables		*
; *******************************************************
 
    ;GET option.a
    ;GET memcfg.a
    GET memcfg.s

;Memory Area
;GCS6 64M 16bit(8MB) DRAM/SDRAM(0xc000000-0xc7fffff)
;APP    RAM=0xc000000~0xc7effff 
;44BMON RAM=0xc7f0000-0xc7fffff
;STACK	   =0xc7ffa00		   

;Interrupt Control
INTPND	    EQU	0x01e00004
INTMOD	    EQU	0x01e00008
INTMSK	    EQU	0x01e0000c
I_ISPR	    EQU	0x01e00020
I_CMST	    EQU	0x01e0001c

;Watchdog timer
WTCON	    EQU	0x01d30000

;Clock Controller
PLLCON	    EQU	0x01d80000
CLKCON	    EQU	0x01d80004
LOCKTIME    EQU	0x01d8000c
	
;Memory Controller
REFRESH	    EQU 0x01c80024

;BDMA destination register
BDIDES0     EQU 0x1f80008
BDIDES1     EQU 0x1f80028

;Pre-defined constants
USERMODE    EQU	0x10
FIQMODE	    EQU	0x11
IRQMODE	    EQU	0x12
SVCMODE	    EQU	0x13
ABORTMODE   EQU	0x17
UNDEFMODE   EQU	0x1b
MODEMASK    EQU	0x1f
NOINT	    EQU	0xc0

;check if tasm.exe is used.
    GBLL    THUMBCODE    ;global logical variable, init. to {false}
    [ {CONFIG} = 16	     ;[=if,{CONFIG}:build-in variable defined by ARM assembler,16=assembing Thumbcode.
THUMBCODE SETL	{TRUE}   ;SETL:set the logic variable
    CODE32               ;changing from Thumb state to Arm state
    |                    ;|=else
THUMBCODE SETL	{FALSE}
    ]                    ;]=endif

    [ THUMBCODE
    CODE32               ;for start-up code for Thumb mode???
    ]

    MACRO
$HandlerLabel HANDLER $HandleLabel

$HandlerLabel
    sub	    sp,sp,#4	    ;decrement sp(to store jump address)
    stmfd   sp!,{r0}	    ;PUSH the work register to stack(lr does't push because it return to original address)
    ldr	    r0,=$HandleLabel;load the address of HandleXXX to r0
    ldr	    r0,[r0]	        ;load the contents(service routine start address) of HandleXXX
    str	    r0,[sp,#4]	    ;store the contents(ISR) of HandleXXX to stack
    ldmfd   sp!,{r0,pc}	    ;POP the work register and pc(jump to ISR)
    MEND

    IMPORT	|Image$$RO$$Limit|  ; End of ROM code (=start of ROM data)
    IMPORT	|Image$$RW$$Base|   ; Base of RAM to initialise
    IMPORT	|Image$$ZI$$Base|   ; Base and limit of area
    IMPORT	|Image$$ZI$$Limit|  ; to zero initialise;

    IMPORT  Main    ; The main entry of mon program 

    AREA    Init,CODE,READONLY

    ENTRY 
;****************************************************************************
    b      ResetHandler                      ;    Reset        
    ldr    pc, =(_IRQ_BASEADDRESS + 0x04)    ;    HandlerUndef 
    ldr    pc, =(_IRQ_BASEADDRESS + 0x08)    ;    HandlerSWI 
    ldr    pc, =(_IRQ_BASEADDRESS + 0x0C)    ;    HandlerPabort 
    ldr    pc, =(_IRQ_BASEADDRESS + 0x10)    ;    HandlerDAbort
    ldr    pc, =(_IRQ_BASEADDRESS + 0x14)    ;    HandlerReserved
    ldr    pc, =(_IRQ_BASEADDRESS + 0x18)    ;    HandlerIRQ
    ldr    pc, =(_IRQ_BASEADDRESS + 0x1C)    ;    HandlerFIQ
;***************************************************************************    
	;***IMPORTANT NOTE***
	;If the H/W vectored interrutp mode is enabled, The above two instructions should
	;be changed like below, to work-around with H/W bug of S3C44B0X interrupt controller. 
	; b HandlerIRQ  ->  subs pc,lr,#4
	; b HandlerIRQ  ->  subs pc,lr,#4

VECTOR_BRANCH
    ldr pc,=HandlerEINT0    ;mGA    H/W interrupt vector table
    ldr pc,=HandlerEINT1    ;	
    ldr pc,=HandlerEINT2    ;
    ldr pc,=HandlerEINT3    ;
    ldr pc,=HandlerEINT4567 ;
    ldr pc,=HandlerTICK	    ;mGA
    b .
    b .
    ldr pc,=HandlerZDMA0    ;mGB
    ldr pc,=HandlerZDMA1    ;
    ldr pc,=HandlerBDMA0    ;
    ldr pc,=HandlerBDMA1    ;
    ldr pc,=HandlerWDT	    ;
    ldr pc,=HandlerUERR01   ;mGB
    b .
    b .
    ldr pc,=HandlerTIMER0   ;mGC
    ldr pc,=HandlerTIMER1   ;
    ldr pc,=HandlerTIMER2   ;
    ldr pc,=HandlerTIMER3   ;
    ldr pc,=HandlerTIMER4   ;
    ldr pc,=HandlerTIMER5   ;mGC
    b .
    b .
    ldr pc,=HandlerURXD0    ;mGD
    ldr pc,=HandlerURXD1    ;
    ldr pc,=HandlerIIC	    ;
    ldr pc,=HandlerSIO	    ;
    ldr pc,=HandlerUTXD0    ;
    ldr pc,=HandlerUTXD1    ;mGD
    b .
    b .
    ldr pc,=HandlerRTC	    ;mGKA
    b .						;
    b .						;
    b .						;
    b .						;
    b .						;mGKA
    b .
    b .
    ldr pc,=HandlerADC	    ;mGKB
    b .						;
    b .						;
    b .						;
    b .						;
    b .						;mGKB
    b .
    b .
;0xe0=EnterPWDN
    ldr pc,=EnterPWDN

    LTORG	

HandlerFIQ	HANDLER HandleFIQ
HandlerIRQ	HANDLER HandleIRQ
HandlerUndef	HANDLER HandleUndef
HandlerSWI	HANDLER HandleSWI
HandlerDabort	HANDLER HandleDabort
HandlerPabort	HANDLER HandlePabort

HandlerADC	HANDLER HandleADC
HandlerRTC	HANDLER HandleRTC
HandlerUTXD1	HANDLER HandleUTXD1
HandlerUTXD0	HANDLER HandleUTXD0
HandlerSIO	HANDLER HandleSIO
HandlerIIC	HANDLER HandleIIC
HandlerURXD1	HANDLER HandleURXD1
HandlerURXD0	HANDLER HandleURXD0
HandlerTIMER5	HANDLER HandleTIMER5
HandlerTIMER4	HANDLER HandleTIMER4
HandlerTIMER3	HANDLER HandleTIMER3
HandlerTIMER2	HANDLER HandleTIMER2
HandlerTIMER1	HANDLER HandleTIMER1
HandlerTIMER0	HANDLER HandleTIMER0
HandlerUERR01	HANDLER HandleUERR01
HandlerWDT	HANDLER HandleWDT
HandlerBDMA1	HANDLER HandleBDMA1
HandlerBDMA0	HANDLER HandleBDMA0
HandlerZDMA1	HANDLER HandleZDMA1
HandlerZDMA0	HANDLER HandleZDMA0
HandlerTICK	HANDLER HandleTICK
HandlerEINT4567	HANDLER HandleEINT4567
HandlerEINT3	HANDLER HandleEINT3
HandlerEINT2	HANDLER HandleEINT2
HandlerEINT1	HANDLER HandleEINT1
HandlerEINT0	HANDLER HandleEINT0

;*************************************************************************
;IRQ  ==the program put this phrase to 0xc000000

ExceptionHanlderBegin
    b      .
    ldr    pc, MyHandleUndef            ;    HandlerUndef 
    ldr    pc, MyHandleSWI              ;    HandlerSWI 
    ldr    pc, MyHandlePabort           ;    HandlerPabort 
    ldr    pc, MyHandleDabort           ;    HandlerDAbort
    b .                                 ;    HandlerReserved
    ldr    pc, MyHandleIRQ              ;    HandlerIRQ
    ldr    pc, MyHandleFIQ              ;    HandlerFIQ
    
MyHandleUndef  DCD  HandleUndef         ;reserve a word(32bit)
MyHandleSWI    DCD  HandleSWI 
MyHandlePabort DCD  HandlePabort
MyHandleDabort DCD  HandleDabort
MyHandleIRQ    DCD  HandleIRQ
MyHandleFIQ    DCD  HandleFIQ

ExceptionHanlderEnd
;*************************************************************************

;One of the following two routines can be used for non-vectored interrupt.

IsrIRQ	;using I_ISPR register.
    sub	    sp,sp,#4       ;reserved for PC
    stmfd   sp!,{r8-r9}   

	;IMPORTANT CAUTION
	;if I_ISPC isn't used properly, I_ISPR can be 0 in this routine.

    ldr	    r9,AddrISPR;=I_ISPR
    ldr	    r9,[r9]

	cmp		r9, #0x0	;If the IDLE mode work-around is used,
						;r9 may be 0 sometimes.
	beq		%F2

    mov	    r8,#0x0
0
    movs    r9,r9,lsr #1
    bcs	    %F1
    add	    r8,r8,#4
    b	    %B0

1
    ldr	    r9,AddrHandleADC;=HandleADC
    add	    r9,r9,r8
    ldr	    r9,[r9]
    str	    r9,[sp,#8]
    ldmfd   sp!,{r8-r9,pc}

2
	ldmfd	sp!,{r8-r9}
	add		sp,sp,#4
	subs	pc,lr,#4
	
AddrISPR;There is no this phrases in original 44binit.s
    DCD     I_ISPR
AddrHandleADC    
    DCD     HandleADC
IsrIRQEnd  

;****************************************************
;*	START											*
;****************************************************
ResetHandler
    ldr	    r0,=WTCON	    ;watch dog disable 
    ldr	    r1,=0x0 		
    str	    r1,[r0]

    ldr	    r0,=INTMSK
    ldr	    r1,=0x07ffffff  ;all interrupt disable
    str	    r1,[r0]

    ;****************************************************
    ;*	Set clock control registers						*
    ;****************************************************
    ldr	r0,=LOCKTIME
    ldr	r1,=0xfff
    str	r1,[r0]

    [ PLLONSTART
	ldr	r0,=PLLCON			;temporary setting of PLL
	ldr	r1,=((M_DIV<<12)+(P_DIV<<4)+S_DIV)	;Fin=10MHz,Fout=40MHz
	str	r1,[r0]
    ]

    ldr	    r0,=CLKCON		 
    ldr	    r1,=0x7ff8	    ;All unit block CLK enable	
    str	    r1,[r0]