;=========================================
; NAME: 2410INIT.S
; DESC: C start up codes
;       Configure memory, ISR ,stacks
;   Initialize C-variables
; HISTORY:
; 2002.02.25:kwtark: ver 0.0
; 2002.03.20:purnnamu: Add some functions for testing STOP,POWER_OFF mode
; 2002.04.10:SJS:sub interrupt disable 0x3ff -> 0x7ff 
; 2002.11.29:Kong:DCD BANKSIZE Resiger 0x32 -> 0xb2 (ARM core burst enable)
;=========================================

    GET option.inc
    GET memcfg.inc
    GET 2410addr.inc

BIT_SELFREFRESH EQU (1<<22)

;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

;The location of stacks
UserStack   EQU (_STACK_BASEADDRESS-0x3800)     ;0x33ff4800 ~ 
SVCStack    EQU (_STACK_BASEADDRESS-0x2800)     ;0x33ff5800 ~
UndefStack  EQU (_STACK_BASEADDRESS-0x2400)     ;0x33ff5c00 ~
AbortStack  EQU (_STACK_BASEADDRESS-0x2000)     ;0x33ff6000 ~
IRQStack    EQU (_STACK_BASEADDRESS-0x1000)     ;0x33ff7000 ~
FIQStack    EQU (_STACK_BASEADDRESS-0x0)        ;0x33ff8000 ~ 

;Check if tasm.exe(armasm -16 ...@ADS 1.0) is used.
    GBLL    THUMBCODE
    [ {CONFIG} = 16 
THUMBCODE SETL  {TRUE}
        CODE32
        |   
THUMBCODE SETL  {FALSE}
        ]

        MACRO
    MOV_PC_LR
        [ THUMBCODE
            bx lr
        |
            mov pc,lr
        ]
    MEND

        MACRO
    MOVEQ_PC_LR
        [ THUMBCODE
            bxeq lr
        |
            moveq pc,lr
        ]
    MEND

        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 

    ;1)The code, which converts to Big-endian, should be in little endian code.
    ;2)The following little endian code will be compiled in Big-Endian mode. 
    ;  The code byte order should be changed as the memory bus width.
    ;3)The pseudo instruction,DCD can't be used here because the linker generates error.
    ASSERT  :DEF:ENDIAN_CHANGE
    [ ENDIAN_CHANGE
        ASSERT  :DEF:ENTRY_BUS_WIDTH
        [ ENTRY_BUS_WIDTH=32
        b   ChangeBigEndian     ;DCD 0xea000007 
        ]
        
        [ ENTRY_BUS_WIDTH=16
        andeq   r14,r7,r0,lsl #20   ;DCD 0x0007ea00
        ]
        
        [ ENTRY_BUS_WIDTH=8
        streq   r0,[r0,-r10,ror #1] ;DCD 0x070000ea
            ]
    |
        b   ResetHandler  
        ]
    b   HandlerUndef    ;handler for Undefined mode
    b   HandlerSWI      ;handler for SWI interrupt
    b   HandlerPabort   ;handler for PAbort
    b   HandlerDabort   ;handler for DAbort
    b   .               ;reserved
    b   HandlerIRQ      ;handler for IRQ interrupt 
    b   HandlerFIQ      ;handler for FIQ interrupt

;@0x20
    b   EnterPWDN
ChangeBigEndian
;@0x24
    [ ENTRY_BUS_WIDTH=32
        DCD 0xee110f10  ;0xee110f10 => mrc p15,0,r0,c1,c0,0
        DCD 0xe3800080  ;0xe3800080 => orr r0,r0,#0x80;  //Big-endian
        DCD 0xee010f10  ;0xee010f10 => mcr p15,0,r0,c1,c0,0
    ]
    [ ENTRY_BUS_WIDTH=16
        DCD 0x0f10ee11
        DCD 0x0080e380  
        DCD 0x0f10ee01  
    ]
    [ ENTRY_BUS_WIDTH=8
        DCD 0x100f11ee  
        DCD 0x800080e3  
        DCD 0x100f01ee  
        ]
    DCD 0xffffffff  ;swinv 0xffffff is similar with NOP and run well in both endian mode. 
    DCD 0xffffffff
    DCD 0xffffffff
    DCD 0xffffffff
    DCD 0xffffffff
    b ResetHandler
    
;Function for entering power down mode
; 1. SDRAM should be in self-refresh mode.
; 2. All interrupt should be maksked for SDRAM/DRAM self-refresh.
; 3. LCD controller should be disabled for SDRAM/DRAM self-refresh.
; 4. The I-cache may have to be turned on. 
; 5. The location of the following code may have not to be changed.

;void EnterPWDN(int CLKCON); 
EnterPWDN           
    mov r2,r0               ;r2=rCLKCON
    tst r0,#0x8             ;POWER_OFF mode?
    bne ENTER_POWER_OFF

ENTER_STOP  
    ldr r0,=REFRESH     
    ldr r3,[r0]                     ;r3=rREFRESH    
    mov r1, r3
    orr r1, r1, #BIT_SELFREFRESH
    str r1, [r0]                    ;Enable SDRAM self-refresh

    mov r1,#16          ;wait until self-refresh is issued. may not be needed.
0   subs r1,r1,#1
    bne %B0

    ldr r0,=CLKCON      ;enter STOP mode.
    str r2,[r0]    

    mov r1,#32
0   subs r1,r1,#1   ;1) wait until the STOP mode is in effect.
    bne %B0         ;2) Or wait here until the CPU&Peripherals will be turned-off
                    ;   Entering POWER_OFF mode, only the reset by wake-up is available.

    ldr r0,=REFRESH     ;exit from SDRAM self refresh mode.
    str r3,[r0]
    
    MOV_PC_LR

ENTER_POWER_OFF 
    ;NOTE.
    ;1) rGSTATUS3 should have the return address after wake-up from POWER_OFF mode.
    
    ldr r0,=REFRESH     
    ldr r1,[r0]                     ;r1=rREFRESH    
    orr r1, r1, #BIT_SELFREFRESH
    str r1, [r0]                    ;Enable SDRAM self-refresh

    mov r1,#16          ;Wait until self-refresh is issued,which may not be needed.
0   subs r1,r1,#1
    bne %B0

    ldr     r1,=MISCCR
    ldr r0,[r1]
    orr r0,r0,#(7<<17)  ;Make sure that SCLK0:SCLK->0, SCLK1:SCLK->0, SCKE=L during boot-up 
    str r0,[r1]

    ldr r0,=CLKCON
    str r2,[r0]    

    b .                 ;CPU will die here.
    

WAKEUP_POWER_OFF
    ;Release SCLKn after wake-up from the POWER_OFF mode.
    ldr r1,=MISCCR
    ldr r0,[r1]
    bic r0,r0,#(7<<17)      ;SCLK0:0->SCLK, SCLK1:0->SCLK, SCKE:L->H
    str r0,[r1]
    
    ;Set memory control registers
    ldr r0,=SMRDATA
    ldr r1,=BWSCON      ;BWSCON Address
    add r2, r0, #52     ;End address of SMRDATA
0       
    ldr r3, [r0], #4    
    str r3, [r1], #4    
    cmp r2, r0      
    bne %B0

    mov r1,#256
0   subs r1,r1,#1       ;1) wait until the SelfRefresh is released.
    bne %B0 

    ldr r1,=GSTATUS3    ;GSTATUS3 has the start address just after POWER_OFF wake-up
    ldr r0,[r1]
    mov pc,r0

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

IsrIRQ  
    sub     sp,sp,#4       ;reserved for PC
    stmfd   sp!,{r8-r9}   
    
    ldr     r9,=INTOFFSET
    ldr     r9,[r9]
    ldr     r8,=HandleEINT0
    add     r8,r8,r9,lsl #2
    ldr     r8,[r8]
    str     r8,[sp,#8]
    ldmfd   sp!,{r8-r9,pc}

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

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

    ldr r0,=INTSUBMSK
    ldr r1,=0x7ff           ;all sub interrupt disable, 2002/04/10
    str r1,[r0]

   ; [ {FALSE}
        ; rGPFDAT = (rGPFDAT & ~(0xf<<4)) | ((~data & 0xf)<<4);    
        ; Led_Display
    ldr r0,=GPFCON
    ldr r1,=0x5500      
    str r1,[r0]
    ldr r0,=GPFDAT
    ldr r1,=0x10
    str r1,[r0]
   ; ]

    ;To reduce PLL lock time, adjust the LOCKTIME register. 
    ldr r0,=LOCKTIME
    ldr r1,=0xffffff
    str r1,[r0]
        
        [ PLL_ON_START
    ;Configure MPLL
    ldr r0,=MPLLCON          
    ldr r1,=((M_MDIV<<12)+(M_PDIV<<4)+M_SDIV)  ;Fin=12MHz,Fout=50MHz
    str r1,[r0]
    ]

    ;Check if the boot is caused by the wake-up from POWER_OFF mode.
    ldr r1,=GSTATUS2
    ldr r0,[r1]
    tst r0,#0x2
        ;In case of the wake-up from POWER_OFF mode, go to POWER_OFF_WAKEUP handler. 
    bne WAKEUP_POWER_OFF

    EXPORT StartPointAfterPowerOffWakeUp
StartPointAfterPowerOffWakeUp

    ;Set memory control registers
    ldr r0,=SMRDATA
    ldr r1,=BWSCON      ;BWSCON Address
    add r2, r0, #52     ;End address of SMRDATA
0       
    ldr r3, [r0], #4    
    str r3, [r1], #4    
    cmp r2, r0      
    bne %B0
    
        ;Initialize stacks
    bl  InitStacks
    
    ; Setup IRQ handler
    ldr r0,=HandleIRQ       ;This routine is needed
    ldr r1,=IsrIRQ          ;if there isn't 'subs pc,lr,#4' at 0x18, 0x1c
    str r1,[r0]

    ;Copy and paste RW data/zero initialized data
    ldr r0, =|Image$$RO$$Limit|     ; Get pointer to ROM data
    ldr r1, =|Image$$RW$$Base|      ; and RAM copy
    ldr r3, =|Image$$ZI$$Base|  
    
    ;Zero init base => top of initialised data
    cmp r0, r1      ; Check that they are different
    beq %F2
1       
    cmp r1, r3      ; Copy init data
    ldrcc   r2, [r0], #4    ;--> LDRCC r2, [r0] + ADD r0, r0, #4         
    strcc   r2, [r1], #4    ;--> STRCC r2, [r1] + ADD r1, r1, #4
    bcc %B1
2       
    ldr r1, =|Image$$ZI$$Limit| ; Top of zero init segment
    mov r2, #0
3       
    cmp     r3, r1      ; Zero init
    strcc   r2, [r3], #4
    bcc     %B3

    

    [ :LNOT:THUMBCODE
        bl  Main        ;Don't use main() because ......
        b   .                       
    ]

    [ THUMBCODE         ;for start-up code for Thumb mode
        orr lr,pc,#1
        bx  lr
        CODE16
        bl  Main        ;Don't use main() because ......
        b   .
        CODE32
    ]


;function initializing stacks
InitStacks
    ;Don't use DRAM,such as stmfd,ldmfd......
    ;SVCstack is initialized before
    ;Under toolkit ver 2.5, 'msr cpsr,r1' can be used instead of 'msr cpsr_cxsf,r1'
    mrs r0,cpsr
    bic r0,r0,#MODEMASK
    orr r1,r0,#UNDEFMODE|NOINT
    msr cpsr_cxsf,r1                ;UndefMode
    ldr sp,=UndefStack
    
    orr r1,r0,#ABORTMODE|NOINT
    msr cpsr_cxsf,r1                ;AbortMode
    ldr sp,=AbortStack

    orr r1,r0,#IRQMODE|NOINT
    msr cpsr_cxsf,r1                ;IRQMode
    ldr sp,=IRQStack
    
    orr r1,r0,#FIQMODE|NOINT
    msr cpsr_cxsf,r1                ;FIQMode
    ldr sp,=FIQStack

    bic r0,r0,#MODEMASK|NOINT
    orr r1,r0,#SVCMODE
    msr cpsr_cxsf,r1                ;SVCMode
    ldr sp,=SVCStack
    
    ;USER mode has not be initialized.
    
    mov pc,lr 
    ;The LR register won't be valid if the current mode is not SVC mode.
    

    LTORG

SMRDATA DATA
; Memory configuration should be optimized for best performance 
; The following parameter is not optimized.                     
; Memory access cycle parameter strategy
; 1) The memory settings is  safe parameters even at HCLK=75Mhz.
; 2) SDRAM refresh period is for HCLK=75Mhz. 

    DCD (0+(B1_BWSCON<<4)+(B2_BWSCON<<8)+(B3_BWSCON<<12)+(B4_BWSCON<<16)+(B5_BWSCON<<20)+(B6_BWSCON<<24)+(B7_BWSCON<<28))
    DCD ((B0_Tacs<<13)+(B0_Tcos<<11)+(B0_Tacc<<8)+(B0_Tcoh<<6)+(B0_Tah<<4)+(B0_Tacp<<2)+(B0_PMC))   ;GCS0
    DCD ((B1_Tacs<<13)+(B1_Tcos<<11)+(B1_Tacc<<8)+(B1_Tcoh<<6)+(B1_Tah<<4)+(B1_Tacp<<2)+(B1_PMC))   ;GCS1 
    DCD ((B2_Tacs<<13)+(B2_Tcos<<11)+(B2_Tacc<<8)+(B2_Tcoh<<6)+(B2_Tah<<4)+(B2_Tacp<<2)+(B2_PMC))   ;GCS2
    DCD ((B3_Tacs<<13)+(B3_Tcos<<11)+(B3_Tacc<<8)+(B3_Tcoh<<6)+(B3_Tah<<4)+(B3_Tacp<<2)+(B3_PMC))   ;GCS3
    DCD ((B4_Tacs<<13)+(B4_Tcos<<11)+(B4_Tacc<<8)+(B4_Tcoh<<6)+(B4_Tah<<4)+(B4_Tacp<<2)+(B4_PMC))   ;GCS4
    DCD ((B5_Tacs<<13)+(B5_Tcos<<11)+(B5_Tacc<<8)+(B5_Tcoh<<6)+(B5_Tah<<4)+(B5_Tacp<<2)+(B5_PMC))   ;GCS5
    DCD ((B6_MT<<15)+(B6_Trcd<<2)+(B6_SCAN))    ;GCS6
    DCD ((B7_MT<<15)+(B7_Trcd<<2)+(B7_SCAN))    ;GCS7
;   DCD ((REFEN<<23)+(TREFMD<<22)+(Trp<<20)+(Trc<<18)+(Tchr<<16)+REFCNT)    ;Tchr not used bit
    DCD ((REFEN<<23)+(TREFMD<<22)+(Trp<<20)+(Trc<<18)+REFCNT)       



;   DCD 0x32            ;SCLK power saving mode, ARM core burst disable, BANKSIZE 128M/128M
    DCD 0xb2            ;SCLK power saving mode, ARM core burst enable , BANKSIZE 128M/128M - 11/29/2002

    DCD 0x30            ;MRSR6 CL=3clk
    DCD 0x30            ;MRSR7
;   DCD 0x20            ;MRSR6 CL=2clk
;   DCD 0x20            ;MRSR7

    ALIGN


    AREA RamData, DATA, READWRITE

    ^   _ISR_STARTADDRESS
HandleReset     #   4
HandleUndef     #   4
HandleSWI       #   4
HandlePabort    #   4
HandleDabort    #   4
HandleReserved  #   4
HandleIRQ       #   4
HandleFIQ       #   4

;Don't use the label 'IntVectorTable',
;The value of IntVectorTable is different with the address you think it may be.
;IntVectorTable
HandleEINT0     #   4
HandleEINT1     #   4
HandleEINT2     #   4
HandleEINT3     #   4
HandleEINT4_7   #   4
HandleEINT8_23  #   4
HandleRSV6      #   4
HandleBATFLT    #   4
HandleTICK      #   4
HandleWDT       #   4
HandleTIMER0    #   4
HandleTIMER1    #   4
HandleTIMER2    #   4
HandleTIMER3    #   4
HandleTIMER4    #   4
HandleUART2     #   4
HandleLCD       #   4
HandleDMA0      #   4
HandleDMA1      #   4
HandleDMA2      #   4
HandleDMA3      #   4
HandleMMC       #   4
HandleSPI0      #   4
HandleUART1     #   4
HandleRSV24     #   4
HandleUSBD      #   4
HandleUSBH      #   4
HandleIIC       #   4
HandleUART0     #   4
HandleSPI1      #   4
HandleRTC       #   4
HandleADC       #   4

    END