ARM裸机篇---启动代码分析
先搞清楚启动代码和Bootloader的区别，启动代码是指CPU复位后到进入C语言的main函数之前需要执行的那段汇编代码。
下面的代码先暂且这样吧，没啥注释的，时间关系，我还是先搞些应用再说^_^
;=========================================
; 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
;=========================================
GET option.s
GET memcfg.s
GET 2410addr.s
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)
DCD 0x32 ;SCLK power saving mode, BANKSIZE 128M/128M
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
上面这个还没啥注释的，下面请看这个有注释的吧，这个是实验室买的设备带的：
;*--------------------------------------------- 文件信息 ----------------------------------------------------
;*
;* 文件名称 : 2410INIT.S
;* 文件功能 : 该文件为ARM9硬件平台的C语言启动代码，用于分配中断向量表，初始化ISR地址，初始化堆栈空间，
;* 初始化应用程序执行环境，配置存储器系统，设定时钟周期，呼叫主应用程序。
;* 补充说明 : 基于S3C2410的ARM9硬件平台的启动代码
;*-------------------------------------------- 最新版本信息 -------------------------------------------------
;* 修改作者 : ARM开发小组
;* 修改日期 : 2005/08/23
;* 版本声明 : V1.0.1
;*-------------------------------------------- 历史版本信息 -------------------------------------------------
;* 文件作者 : ARM开发小组
;* 创建日期 : 2004/04/20
;* 版本声明 : v1.0.0
;*-----------------------------------------------------------------------------------------------------------
;*-----------------------------------------------------------------------------------------------------------
;************************************************************************************************************
;*/
GET option.s
GET memcfg.s
GET 2410addr.s
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,=((0xa1<<12)+(3<<4)+0x1) ;//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
;//呼叫主应用程序
b UART
UART
ldr r0, =GPHCON ;//设置RxD0,TxD0引脚
ldr r1, =0x2afaaa
str r1, [r0]
ldr r0, =GPHUP
ldr r1, =0x7ff
str r1, [r0] ; // The pull up function is disabled GPH[10:0]
ldr r0, =UFCON0 ;//禁用FIFO
ldr r1, =0x0
str r1, [r0]
ldr r0, =UMCON0 ;//禁用AFC
ldr r1, =0x0
str r1, [r0]
ldr r0, =ULCON0 ;//设置线寄存器
ldr r1, =0x3 ; //UART LINE CONFIG 正常模式,无奇偶校验,一个停止位,8个数据位
str r1, [r0]
ldr r0, =UCON0 ;//设置Uart0控制器
ldr r1, =0x245;//RX边沿触发,TX电平触发,禁用延时中断,使用RX 错误中断,正常操作模式,中断请求或表决模式
str r1, [r0]
ldr r0, =UBRDIV0 ;//设置波特率为115200
ldr r1, =0x1a ;//int(50700000 / 16 / 115200) - 1 = 26
str r1, [r0]
mov r1, #100
Delay
sub r1, r1, #0x1
bne Delay
;//开中断
ldr r0, =INTMSK
ldr r1, [r0]
and r1, r1, #0xefffffff
str r1, [r0]
MOV R5 , #127 ;//设置要打印的字符的个数
MOV R1 , #0x0 ;//设置要打印的字符
LOOP
LDR R3 , =UTRSTAT0
LDR R2 , [R3]
TST R2 ,#0x04 ;//判断发送缓冲区是否为空
BEQ LOOP ;//为空则执行下边的语句，不为空则跳转到LOOP
LDR R0 , =UTXH0
STR R1 ,[R0] ;//向数据缓冲区放置要发送的数据
ADD R1, R1, #1
SUB R5 ,R5, #0x01 ;//计数器减一
CMP R5 ,#0x0
BNE LOOP
LOOP2 B LOOP2
; /*
; pclk = PCLK;
; rUFCON0 = 0x0; //UART channel 0 FIFO control register, FIFO disable
; rUFCON1 = 0x0; //UART channel 1 FIFO control register, FIFO disable
; rUFCON2 = 0x0; //UART channel 2 FIFO control register, FIFO disable
; rUMCON0 = 0x0; //UART chaneel 0 MODEM control register, AFC disable
; rUMCON1 = 0x0; //UART chaneel 1 MODEM control register, AFC disable
;//UART0
; rULCON0 = 0x3; //Line control register : Normal,No parity,1 stop,8 bits
; // [10] [9] [8] [7] [6] [5] [4] [3:2] [1:0]
; // Clock Sel, Tx Int, Rx Int, Rx Time Out, Rx err, Loop-back, Send break, Transmit Mode, Receive Mode
; // 0 1 0 , 0 1 0 0 , 01 01
; // PCLK Level Pulse Disable Generate Normal Normal Interrupt or Polling
; rUCON0 = 0x245; // Control register
;// rUBRDIV0=( (int)(pclk/16./baud) -1 ); //Baud rate divisior register 0
; rUBRDIV0=( (int)(pclk/16./baud+0.5) -1 ); //Baud rate divisior register 0
;//UART1
; rULCON1 = 0x3;
; rUCON1 = 0x245;
; rUBRDIV1=( (int)(pclk/16./baud) -1 );
;
;//UART2
; rULCON2 = 0x3;
; rUCON2 = 0x245;
; rUBRDIV2=( (int)(pclk/16./baud) -1 );
;
; for(i=0;i<100;i++);
;
; */
;//END OF UART HERE
;//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
; incbin ..\..\Font\Hzk16.bin
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)
DCD 0x32 ;//SCLK power saving mode, BANKSIZE 128M/128M
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