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; *******************************************************
; * NAME : INIT.S *
; * Version : 28.May.2003 *
; * Description: *
; * C start up codes *
; * Configure memory, Initialize ISR ,stacks *
; * Initialize C-variables *
; * Fill zeros into zero-initialized C-variables *
; *******************************************************
GET ..\inc\memcfg.inc
GET ..\inc\miscel.inc
;Memory Area
;GCS6 64M 16bit(8MB) SDRAM(0xc000000-0xc7fffff)
;APP RAM=0xc000000~0xc7effff
;44BMON RAM=0xc7f0000-0xc7fffff
;STACK =0xc7ffa00
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 bios_main
CODE32 ;for start-up code for Thumb mode
AREA Init,CODE,READONLY
ENTRY
b ResetHandler ;for debug
b HandlerUndef ;handlerUndef
b HandlerSWI ;SWI interrupt handler
; b HandlerPabort ;handlerPAbort
; b HandlerDabort ;handlerDAbort
; b . ;handlerReserved
; b HandlerIRQ ;handlerIRQ
; b HandlerFIQ ;handlerFIQ
HandlerSWI
movs pc,r14
HandlerUndef
movs pc,r14
;****************************************************
;* 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]
ldr r0,=PLLCON ;temporary setting of PLL
ldr r1,=((M_DIV<<12)+(P_DIV<<4)+S_DIV) ;Fin=12MHz,Fout=60MHz
str r1,[r0]
ldr r0,=CLKCON
ldr r1,=0x7ff8 ;All unit block CLK enable
str r1,[r0]
;****************************************
;* change BDMACON reset value for BDMA *
;****************************************
ldr r0,=BDIDES0
ldr r1,=0x40000000 ;BDIDESn reset value should be 0x40000000
str r1,[r0]
ldr r0,=BDIDES1
ldr r1,=0x40000000 ;BDIDESn reset value should be 0x40000000
str r1,[r0] ;DMA FOR IDE
;****************************************************
;* Set memory control registers *
;****************************************************
ldr r0,=SMRDATA
ldmia r0,{r1-r13}
ldr r0,=0x01c80000 ;BWSCON Address
stmia r0,{r1-r13}
;****************************************************
;* Initialize stacks *
;****************************************************
ldr sp, =SVCStack
bl InitStacks
bl bios_main
;****************************************************
;* The function for initializing stack *
;****************************************************
InitStacks
;Don't use DRAM,such as stmfd,ldmfd......
;SVCstack is initialized before
;Under toolkit ver 2.50, '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
orr r1,r0,#SVCMODE|NOINT
msr cpsr_cxsf,r1 ;SVCMode
ldr sp,=SVCStack
;USER mode is not initialized.
mov pc,lr ;The LR register may be not valid for the mode changes.
;****************************************************
;* The function for entering power down mode *
;****************************************************
;void EnterPWDN(int CLKCON);
EnterPWDN
mov r2,r0 ;r0=CLKCON
ldr r0,=REFRESH
ldr r3,[r0]
mov r1, r3
orr r1, r1, #0x400000 ;self-refresh enable
str r1, [r0]
nop ;Wait until self-refresh is issued. May not be needed.
nop ;If the other bus master holds the bus, ...
nop ;mov r0, r0
nop
nop
nop
nop
;enter POWERDN mode
ldr r0,=CLKCON
str r2,[r0]
;wait until enter SL_IDLE,STOP mode and until wake-up
ldr r0,=0x10
0 subs r0,r0,#1
bne %B0
;exit from DRAM/SDRAM self refresh mode.
ldr r0,=REFRESH
str r3,[r0]
mov pc,lr
;*****************************************************************
;* Memory configuration has to be optimized for best performance *
;* The following parameter is not optimized. *
;*****************************************************************
;*** memory access cycle parameter strategy ***
; 1) Even FP-DRAM, EDO setting has more late fetch point by half-clock
; 2) The memory settings,here, are made the safe parameters even at 66Mhz.
; 3) FP-DRAM Parameters:tRCD=3 for tRAC, tcas=2 for pad delay, tcp=2 for bus load.
; 4) DRAM refresh rate is for 40Mhz.
;bank0 16bit BOOT ROM
;bank1 8bit NandFlash
;bank2 16bit IDE
;bank3 8bit UDB
;bank4 rtl8019
;bank5 ext
;bank6 16bit SDRAM
;bank7 16bit SDRAM
LTORG
SMRDATA DATA
DCD 0x11111110 ;Bank0=16bit BootRom(SST39vf160) all 16bit
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) ;REFRESH RFEN=1, TREFMD=0, trp=3clk, trc=5clk, tchr=3clk,count=1019
DCD 0x10 ;SCLK power down mode, BANKSIZE 32M/32M
DCD 0x20 ;MRSR6 CL=2clk
DCD 0x20 ;MRSR7
ALIGN
AREA RamData, DATA, READWRITE
MAP (_VIDEO_ADDRESS)
Videodata FIELD 256*512
MAP (_ISR_STARTADDRESS-256*5-256)
UserStack FIELD 256 ;10001a00
SVCStack FIELD 256 ;10001b00
UndefStack FIELD 256 ;10001c00
AbortStack FIELD 256 ;10001d00
IRQStack FIELD 256 ;10001e00
FIQStack FIELD 0 ;10001e00
END