ARM啟動(dòng)代碼注釋
下邊是完整的工程
本文引用地址:http://butianyuan.cn/article/201611/316916.htm運(yùn)行平臺(tái):mini2440
啟動(dòng)代碼ourdev_444408.rar(文件大小:61K)(原文件名:MicroOS.rar)
;---------------------------------------------------------------------
;startup.s
;系統(tǒng)啟動(dòng)代碼
;起始時(shí)間 : 2009.5.7----->2009.5.11
;---------------------------------------------------------------------
;---------------------------------------------------------------------
GET ./Include/s3c2440.inc ;寄存器地址信息
GET ./Include/memcfg.inc ;內(nèi)存控制器配置信息
;處理器模式
USERMODE EQU 0x10
FIQMODE EQU 0x11
IRQMODE EQU 0x12
SVCMODE EQU 0x13
ABORTMODE EQU 0x17
UNDEFMODE EQU 0x1b
SYSMODE EQU 0x1f
;相關(guān)掩碼
MODEMASK EQU 0x1f
NOINT EQU 0xc0
;各個(gè)處理器模式下堆棧設(shè)置
_STACK_BASEADDRESS EQU 0x33ff8000 ;BANK664MB頂部
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~
;導(dǎo)入操作系統(tǒng)入口函數(shù)
IMP
;導(dǎo)入外部C語言編寫的異常與中斷處理函數(shù)
IMP
IMP
IMP
IMP
IMP
IMP
;導(dǎo)入鏡像裝載域段起始地址
IMP
IMP
IMP
IMP
;--------------------------------------------------------------------
;------------------------------------------------------
AREAstartup,CO
ENTRY
;系統(tǒng)向量表
b vectorRESET ;復(fù)位向量
b vectorUNDEF ;未定義指令
b vectorSWI ;軟中斷
b vectorPABT ;預(yù)取指終止
b vectorDABT ;數(shù)據(jù)終止
b . ;系統(tǒng)保留
b vectorIRQ ;外部中斷
b vectorFIQ ;快速中斷
;-------------------------------------------------------
;--------------------------------------------------------------------------
;復(fù)位向量
;復(fù)位向量是ARM處理器上電后第一個(gè)被執(zhí)行的異常
;此時(shí)系統(tǒng)處理管理(SVC)模式
vectorRESET
;復(fù)位向量有以下六件事要做
;第一步 :關(guān)閉看門狗定時(shí)器屏蔽所有中斷
;第二步:配置系統(tǒng)時(shí)鐘
;第三步 :配置內(nèi)存控制器
;第四步 :配置每種處理器模式下堆棧指針
;第五步 :初始化鏡像運(yùn)行域
;第六步 :跳轉(zhuǎn)到操作系統(tǒng)入口
;------------------------------------------
;第一步 :關(guān)閉看門狗定時(shí)器
;具體內(nèi)容請(qǐng)參看s3c2440a數(shù)據(jù)手冊(cè)的第18章
ldr r0,=WTCON
ldr r1,=0x0
str r1,[r0,#0x0]
;屏蔽所有中斷
ldrr0,=INTMSK
ldrr1,=0xffffffff
strr1,[r0]
;------------------------------------------
;------------------------------------------
;第二步 :配置系統(tǒng)時(shí)鐘
;具體內(nèi)容請(qǐng)看手冊(cè)第7章
;先減少鎖相環(huán)鎖定時(shí)間,s3c2440a要求PLL
;鎖定時(shí)間>300us,在上電時(shí)s3c2440a預(yù)設(shè)值
;mpll為晶體頻率,我用的晶體頻率為12MHz
;300us*12M=3600設(shè)置LOCKTIME=0xfff
;足夠了
ldrr0,=LOCKTIME
ldrr1,=0xfff0fff0 ;高16為對(duì)應(yīng)UPLL
;低16為對(duì)應(yīng)MPLL
strr1,[r0,#0x0]
;根據(jù)器件手冊(cè)我們還有以下幾個(gè)事要做
;step1.配置UPLL
;step2.配置MPLL
;注:手冊(cè)要求先配置UPLL后MPLL
; 且之間要間隔7NOP
; 詳請(qǐng)看手冊(cè)第7-21.
;step3.配置分頻系數(shù)
;step1:
ldrr0,=UPLLCON
ldrr1,=((56<<12)+(2<<4)+2)
ldrr1,[r0]
;按手冊(cè)要求插入7個(gè)NOP
nop
nop
nop
nop
nop
nop
nop
;step2:
ldrr0,=MPLLCON
ldrr1,=((127<<12)+(2<<4)+1)
ldrr1,[r0]
;step3:
ldrr0,=CLKDIVN
ldrr1,=((0<<3)+(2<<2)+1)
ldrr1,[r0]
;------------------------------------------
;------------------------------------------
;第三步 :配置內(nèi)存控制器
;內(nèi)存控制內(nèi)的寄存器器地址是連續(xù)分布的
;從0x4800_0000--0x4800_0030,所以可以
;通過一個(gè)循環(huán)依次填入各個(gè)寄存器的內(nèi)容
ldrr0,=SMRDATA ;裝入配置值的地址
ldrr1,=BWSCON ;裝入起始寄存器地址
addr2,r0,#0x34 ;計(jì)算結(jié)束地址
;下面是用于向內(nèi)存控制器
;裝入配置信息的循環(huán)
0
ldrr3,[r0],#4 ;裝入配置值到r3,后變址
strr3,[r1],#4 ;把r3內(nèi)包含的配置值寫入
;內(nèi)存控制器的寄存器
cmpr2,r0 ;結(jié)束否?
bne%B0 ;沒結(jié)束則繼續(xù)
;------------------------------------------
;------------------------------------------
;第四步 :配置每種處理器模式下堆棧指針
;方法與原則:
;1: 通過CPSR寄存器切換處理器模式
;2: 對(duì)CPSR的操作方式為讀-修改-寫回
;3: 絕對(duì)不要跳到用戶模式,跳過去容易
; 回來就難了
;4:切到新處理器模式后要屏蔽IRQ和FIQ
; 防止在未設(shè)置好堆棧前進(jìn)入中斷處理
; 程序,但是在啟動(dòng)代碼的最先我們已
; 經(jīng)屏蔽了所有的32個(gè)中斷源,所以感
; 覺是否屏蔽都可以
;step1:先把程序狀態(tài)寄存器讀到r0
mrs r0,cpsr
;step2:清除處理器模式位(最前面5位)
bic r0,r0,#MODEMASK
;step3: 設(shè)置未定義狀態(tài)下的堆棧指針
orr r1,r0,#UNDEFMODE|NOINT
msr cpsr_cxsf,r1 ;UndefMode
ldr sp,=UndefStack ;UndefStack=0x33FF_5C00
;step4:設(shè)置終止?fàn)顟B(tài)下的堆棧指針
orr r1,r0,#ABORTMODE|NOINT
msr cpsr_cxsf,r1 ;AbortMode
ldr sp,=AbortStack ;AbortStack=0x33FF_6000
;step5: 設(shè)置中斷模式下的堆棧指針
orr r1,r0,#IRQMODE|NOINT
msr cpsr_cxsf,r1 ;IRQMode
ldr sp,=IRQStack ;IRQStack=0x33FF_7000
;step6: 設(shè)置快速中斷模式下的堆棧指針
orr r1,r0,#FIQMODE|NOINT
msr cpsr_cxsf,r1 ;FIQMode
ldr sp,=FIQStack ;FIQStack=0x33FF_8000
;step7:設(shè)置管理模式下的堆棧指針
orr r1,r0,#SVCMODE|NOINT
msr cpsr_cxsf,r1 ;SVCMode
ldr sp,=SVCStack ;SVCStack=0x33FF_5800
;step8:因?yàn)楣芾砟J脚c用戶模式共用
; 堆棧指針,所以借著系統(tǒng)模式
; 來設(shè)置用戶模式的堆棧指針
orrr1,r0,#SYSMODE|NOINT
msrcpsr_cxsf,r1 ;SYSMode
ldrsp,=UserStack ;SVCStack&USERMode=0x33ff4800
;現(xiàn)在處理器處于系統(tǒng)模式
;------------------------------------------
;------------------------------------------
;第五步 :初始化鏡像運(yùn)行域
;復(fù)制RW段和ZI段到SDRAM指定地址
LDRr0,=|Image$$RO$$Limit|;裝入RO段結(jié)束地址
LDRr1,=|Image$$RW$$Base|;裝入RW段起始地址
LDRr3,=|Image$$ZI$$Base|;裝入ZI段起始地址
;|Image$$RO$$Limit|==|Image$$RW$$Base|?跳過RW段復(fù)制:復(fù)制RW段
CMPr0,r1
BEQ%F2
;復(fù)制RW段
1
CMPr1,r3
LDRCCr2,[r0],#4
STRCCr2,[r1],#4
BCC%B1
2
LDRr1,=|Image$$ZI$$Limit|
MOVr2,#0
;構(gòu)造ZI段
3
CMPr3,r1
STRCCr2,[r3],#4
BCC%B3
;------------------------------------------
;------------------------------------------
;第六步 :跳轉(zhuǎn)到操作系統(tǒng)入口
b OSEntry ;不要使用main,因?yàn)槿绻褂胢ain
;ads還會(huì)調(diào)用_main()初始化RW和ZI
;段,但是那里的數(shù)據(jù)和本程序不同
b .
;------------------------------------------
;---------------------------------------------------------------------------
SMRDATADA
;這里是內(nèi)存控制器的配置數(shù)據(jù)
;配置數(shù)據(jù)需要根據(jù)你使用的存儲(chǔ)器修改
;在第三步時(shí)會(huì)將以下數(shù)據(jù)寫入
;內(nèi)存控制器的相關(guān)寄存器中
;共13個(gè)寄存器的配置值
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)
DCD0x32 ;SCLKpowersavingmode,BANKSIZE128M/128M
DCD0x30 ;MRSR6CL=3clk
DCD0x30 ;MRSR7CL=3clk
ALIGN ;數(shù)據(jù)邊界對(duì)齊
END
我在寫一個(gè)arm920T的微型OS,主要是想借著寫OS的過程學(xué)習(xí)ARM的底層編程,然后跳到Linux。啟動(dòng)代碼是固件的一部分,最經(jīng)學(xué)校要搞個(gè)設(shè)計(jì),不知OS什么時(shí)候能寫好,反正搞定后立即發(fā)帖。
;*
;* 文件名稱 : 2410INIT.S
;* 文件功能 : S3C2410 啟動(dòng)代碼,配置存儲(chǔ)器,ISR,堆棧,初始化C向量地址
;* 補(bǔ)充說明 :
;*-------------------------------------------- 最新版本信息 -------------------------------------------------
;* 修改作者 : ARM開發(fā)小組
;* 修改日期 : 2004/00/00
;* 版本聲明 : V0.1
;*-------------------------------------------- 歷史版本信息 -------------------------------------------------
;* 文件作者 : kwtark(samsung)
;* 創(chuàng)建日期 : 2002/02/25
;* 版本聲明 : 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 2410addr.s ;定義了2410各各寄存器的地址
GET memcfg.s ;定義了2410各內(nèi)存bank的帶寬值和訪問參數(shù)
BIT_SELFREFRESH EQU(1<<22) ;定義了幾個(gè)常數(shù) _STACK_BASEADDRESS EQU 0x33ff8000堆?;刂?/p>
; _ISR_STARTADDRESS EQU 0x33ffff00 中斷向量表基地址
;Pre-defined constants 處理器模式預(yù)定義常量
USERMODE EQU 0x10
FIQMODE EQU 0x11
IRQMODE EQU 0x12
SVCMODE EQU 0x13
ABORTMODE EQU 0x17
UNDEFMODE EQU 0x1b
MODEMASK EQU 0x1f
NOINT EQU 0xc0 ;屏蔽中斷位
;/*************定義處理器各模式下堆棧地址常量*******************/
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...@ADS1.0) is used. ADS編譯器的檢查 */
GBLL THUMBCODE
[ {CONFIG} = 16
THUMBCODE SETL {TRUE}
CO
|
THUMBCODE SETL {FALSE}
]
MACRO
MOV_PC_LR
[ THUMBCODE
bx lr
|
movpc,lr
]
MEND
MACRO
MOVEQ_PC_LR
[ THUMBCODE
bxeq lr
|
moveq pc,lr
]
MEND
;/*******************************************************************************************************/
; 正式代碼的開始,首先是分配中斷向表
;/******************************************************************************************************/
MACRO;先定義了一個(gè)負(fù)責(zé)處理中斷宏
$HandlerLabel HANDLER $HandleLabel
$HandlerLabel
subsp,sp,#4 ;減少sp,保存跳轉(zhuǎn)地址
stmfdsp!,{r0} ;PUSH the work register to stack(lr doest push because it return to original address)
ldr r0,=$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
IMP
IMP
IMP
IMP
IMP
;指示編譯器的符號(hào)不是在本源文件中定義的,而是在其他源文件中
;定義的,在本源文件中可能引用該符號(hào)
AREA Init,CO
ENTRY;程序的入口點(diǎn)
;//1)The co
;//2)The following little endian co
;// The co
;//3)The pseudo instruction,DCD cant be used here because the linker generates error.
ASSERT:DEF:ENDIAN_CHANGE ;//斷言已經(jīng)定義大端模式
[ ENDIAN_CHANGE
ASSERT :DEF:ENTRY_BUS_WIDTH
[ ENTRY_BUS_WIDTH=32
bChangeBigEndian ;DCD 0xea000007
]
[ ENTRY_BUS_WIDTH=16
andeqr14,r7,r0,lsl #20 ;DCD 0x0007ea00
]
[ ENTRY_BUS_WIDTH=8
streqr0,[r0,-r10,ror #1] ;DCD 0x070000ea
]
|
bResetHandler
]
bHandlerUndef ;handler for Undefined mode
bHandlerSWI ;handler for SWI interrupt
bHandlerPabort ;handler for PAbort
bHandlerDabort ;handler for DAbort
b. ;reserved
bHandlerIRQ ;handler for IRQ interrupt
bHandlerFIQ ;handler for FIQ interrupt
;//@0x20
bEnterPWDN
ChangeBigEndian
;//@0x24
[ ENTRY_BUS_WIDTH=32
DCD0xee110f10;0xee110f10 => mrc p15,0,r0,c1,c0,0
DCD0xe3800080;0xe3800080 => orr r0,r0,#0x80; //Big-endian
DCD0xee010f10;0xee010f10 => mcr p15,0,r0,c1,c0,0
]
[ ENTRY_BUS_WIDTH=16
DCD 0x0f10ee11 ;分配一段字的內(nèi)存單元,并用指令的數(shù)據(jù)初始化
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 co
;//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.
0subs r1,r1,#1
bne %B0
ldr r0,=CLKCON ;enter STOP mode.
str r2,[r0]
mov r1,#32
0subs 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, on
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.
0subs r1,r1,#1
bne %B0
ldr r1,=MISCCR
ldrr0,[r1]
orrr0,r0,#(7<<17) ;Make sure that SCLK0:SCLK->0, SCLK1:SCLK->0, SCKE="L" during boot-up
strr0,[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
ldrr0,[r1]
bicr0,r0,#(7<<17) ;SCLK0:0->SCLK, SCLK1:0->SCLK, SCKE:L->H
strr0,[r1]
;Set memory control registers
ldrr0,=SMRDATA
ldrr1,=BWSCON ;BWSCON Address
addr2, r0, #52 ;End address of SMRDATA
0
ldrr3, [r0], #4
strr3, [r1], #4
cmpr2, r0
bne%B0
mov r1,#256
0subs 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
subsp,sp,#4 ;reserved for PC
stmfdsp!,{r8-r9}
ldrr9,=INTOFFSET
ldrr9,[r9]
ldrr8,=HandleEINT0
addr8,r8,r9,lsl #2
ldrr8,[r8]
strr8,[sp,#8]
ldmfdsp!,{r8-r9,pc}
;================================================================================================
; ENTRY 將看門狗、中斷之類的程序關(guān)掉,省得他們來打擾初始化程序的進(jìn)行
;=================================================================================================
ResetHandler
ldrr0,=WTCON ;watch dog disable
ldrr1,=0x0
strr1,[r0]
ldrr0,=INTMSK
ldrr1,=0xffffffff ;all interrupt disable
strr1,[r0]
ldrr0,=INTSUBMSK
ldrr1,=0x7ff ;all sub interrupt disable, 2002/04/10
strr1,[r0]
[ {FALSE}
;rGPFDAT = (rGPFDAT & ~(0xf<<4)) | ((~da
;Led_Display
ldrr0,=GPFCON
ldrr1,=0x5500
strr1,[r0]
ldrr0,=GPFDAT
ldrr1,=0x10
strr1,[r0]
]
;To reduce PLL lock time, adjust the LOCKTIME register.
ldrr0,=LOCKTIME
ldrr1,=0xffffff
strr1,[r0]
[ PLL_ON_START
;Configure MPLL
ldrr0,=MPLLCON;//設(shè)置時(shí)鐘頻率
ldrr1,=((M_MDIV<<12)+(M_PDIV<<4)+M_SDIV) ;Fin=12MHz,Fout=50MHz
strr1,[r0]
]
;Check if the boot is caused by the wake-up from POWER_OFF mode.
ldrr1,=GSTATUS2
ldrr0,[r1]
tstr0,#0x2
;In case of the wake-up from POWER_OFF mode, go to POWER_OFF_WAKEUP handler.
bneWAKEUP_POWER_OFF
EXPORT StartPointAfterPowerOffWakeUp
StartPointAfterPowerOffWakeUp
;Set memory control registers
ldrr0,=SMRDATA
ldrr1,=BWSCON ;BWSCON Address
addr2, r0, #52 ;End address of SMRDATA
0
ldrr3, [r0], #4
strr3, [r1], #4
cmpr2, r0
bne%B0
;Initialize stacks
blInitStacks
;Setup IRQ handler
ldrr0,=HandleIRQ ;This routine is needed
ldrr1,=IsrIRQ ;if there isnt subs pc,lr,#4 at 0x18, 0x1c
strr1,[r0]
;Copy and paste RW da
ldrr0, =|Image$$RO$$Limit| ; Get pointer to ROM da
ldrr1, =|Image$$RW$$Base| ; and RAM copy
ldrr3, =|Image$$ZI$$Base|
;Zero init base => top of initialised da
cmpr0, r1 ;Check that they are different
beq%F2
1
cmpr1, r3 ;Copy init da
ldrccr2, [r0], #4 ;--> LDRCC r2, [r0] + ADD r0, r0, #4
strccr2, [r1], #4 ;--> STRCC r2, [r1] + ADD r1, r1, #4
bcc%B1
2
ldrr1, =|Image$$ZI$$Limit| ;Top of zero init segment
movr2, #0
3
cmpr3, r1 ; Zero init
strccr2, [r3], #4
bcc%B3
[ :LNOT:THUMBCODE
blMain ;Dont use main() because ......
b.
]
[ THUMBCODE ;for start-up co
orrlr,pc,#1
bxlr
CO
blMain ;Dont use main() because ......
b.
CO
]
;//function initializing stacks 初始化堆棧
InitStacks
;Dont 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
mrsr0,cpsr
bicr0,r0,#MODEMASK
orrr1,r0,#UNDEFMODE|NOINT
msrcpsr_cxsf,r1 ;UndefMode
ldrsp,=UndefStack
orrr1,r0,#ABORTMODE|NOINT
msrcpsr_cxsf,r1 ;AbortMode
ldrsp,=AbortStack
orrr1,r0,#IRQMODE|NOINT
msrcpsr_cxsf,r1 ;IRQMode
ldrsp,=IRQStack
orrr1,r0,#FIQMODE|NOINT
msrcpsr_cxsf,r1 ;FIQMode
ldrsp,=FIQStack
bicr0,r0,#MODEMASK|NOINT
orrr1,r0,#SVCMODE
msrcpsr_cxsf,r1 ;SVCMode
ldrsp,=SVCStack
;USER mode has not be initialized.
movpc,lr
;The LR register wont be valid if the current mode is not SVC mode.
LTORG
SMRDATA DA
;// 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, DA
^ _ISR_STARTADDRESS
HandleReset # 4
HandleUndef # 4
HandleSWI # 4
HandlePabort # 4
HandleDabort # 4
HandleReserved # 4
HandleIRQ # 4
HandleFIQ # 4
;//Dont 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
;=========================================
; 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
;=========================================
GET option.s
GET memcfg.s
GET 2410addr.s
BIT_SELFREFRESH EQU (1<<22)
;ARM異常模式的定義
;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
;ARM個(gè)異常模式堆棧
;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...@ADS1.0) is used.
GBLL THUMBCODE
[ {CONFIG} = 16 ;[ = IF
THUMBCODE SETL {TRUE}
CO
| ;| = ELSE
THUMBCODE SETL {FALSE}
] ;] = ENDIF
;宏定義MOV_PC_LR
MACRO
MOV_PC_LR
[ THUMBCODE
bx lr
|
mov pc,lr
]
MEND
MACRO
MOVEQ_PC_LR
[ THUMBCODE
bxeq lr
|
moveq pc,lr
]
MEND
;宏定義-進(jìn)入異常流程
;HANDLER-宏的名稱
;$HandleLabel-宏的參數(shù)
;這個(gè)宏的作用是把各個(gè)中斷程序的地址裝入當(dāng)前的PC,2410有兩種裝斷模式 一種是沒有中斷向量表,一種是使用中斷向量表的
;使用中斷向量表只能是IRQ方式,當(dāng)使用中斷向量表的時(shí)候,中斷發(fā)生時(shí)由2410的中斷控制器自動(dòng)跳轉(zhuǎn)到
;相應(yīng)的位置。
MACRO
$HandlerLabel HANDLER $HandleLabel
$HandlerLabel
sub sp,sp,#4 ;decrement sp(to store jump address)
stmfd sp!,{r0} ;PUSH the work register to stack(lr doest push because it return to original address)!表示數(shù)據(jù)傳送完畢后,將最后的地址寫入基址寄存器
ldr r0,=$HandleLabel;load the address of Handle1XXX 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
;連接器生成的輸出段相關(guān)的符號(hào)
;引入連接器生成的映象文件的各個(gè)部分地址。
;OR-只讀區(qū)域、RW-讀寫區(qū)域、ZI-初始化為0的區(qū)域。
IMP
IMP
IMP
IMP
IMP
;引入外部函數(shù)Main,進(jìn)入C程序。
IMP
;IMP
;定義ARM匯編程序段,段名為SelfBoot,程序段為只讀的代碼段。
AREA SelfBoot, CO
;程序入口地址
ENTRY
ResetEntry
;程序段執(zhí)行的第一跳指令,為8個(gè)異常中斷處理向量,要按順序放置。
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
LTORG ;聲明一個(gè)數(shù)據(jù)緩沖池的開始
HandlerFIQ HANDLER HandleFIQ
HandlerIRQ HANDLER HandleIRQ
HandlerUndef HANDLER HandleUndef
HandlerSWI HANDLER HandleSWI
HandlerDabort HANDLER HandleDabort
HandlerPabort HANDLER HandlePabort
;采用INTOFFSET寄存器判定IRQ中斷源
IsrIRQ
sub sp,sp,#4
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
;======================================================
;初始化程序入口指令
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,=0x3ff ;all sub interrupt disable
str r1,[r0]
;To reduce PLL lock time, adjust the LOCKTIME register.
ldr r0,=LOCKTIME
ldr r1,=0xffffff
str r1,[r0]
;Configure MPLL
ldr r0,=MPLLCON
ldr r1,=((M_MDIV<<12)+(M_PDIV<<4)+M_SDIV) ;Fin=12MHz,Fout=50MHz
str r1,[r0]
;設(shè)置存儲(chǔ)器控制寄存器。
;Set memory control registers
adr r0, SMRDATA
ldr r1,=BWSCON ;BWSCON Address
add r2, r0, #52 ;End address of SMRDATA一共13個(gè)寄存器
0
ldr r3, [r0], #4
str r3, [r1], #4
cmp r2, r0
bne %B0
;禁止Icache和Dcache,禁止MMU
;IMP
;bl MMU_DisableICache ;
;IMP
;bl MMU_DisableDCache ;
;IMP
;bl MMU_InvalidateICache ;
;IMP
;bl MMU_DisableMMU ;
;初始化堆棧
;Initialize stacks
bl InitStacks
;建立IRQ中斷
; Setup IRQ handler
ldr r0,=HandleIRQ ;This routine is needed
ldr r1,=IsrIRQ ;if there isnt subs pc,lr,#4 at 0x18, 0x1c
str r1,[r0]
;===========================================================
adr r0, ResetEntry
ldr r2, BaseOfROM
cmp r0, r2
ldreq r0, TopOfROM
beq InitRam
ldr r3, TopOfROM
;將RO區(qū)域的代碼copy到RW域中并且將ZI區(qū)域初始化為0。
0
ldmia r0!, {r4-r7}
stmia r2!, {r4-r7}
cmp r2, r3
bcc %B0
sub r2, r2, r3
sub r0, r0, r2
InitRam
ldr r2, BaseOfBSS
ldr r3, BaseOfZero
0
cmp r2, r3 ;copy 初始化代碼
ldrcc r1, [r0], #4
strcc r1, [r2], #4
bcc %B0
mov r0, #0 ;初始化ZI區(qū)域?yàn)?
ldr r3, EndOfBSS
1
cmp r2, r3
strcc r0, [r2], #4
bcc %B1
bl Main ;bl Main ;Dont use main() because ......
b .
;堆棧初始化
;function initializing stacks
InitStacks
;Dont 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
;UndefMode堆棧
mrs r0,cpsr
bic r0,r0,#MODEMASK
orr r1,r0,#UNDEFMODE|NOINT
msr cpsr_cxsf,r1 ;UndefMode
ldr sp,=UndefStack
;AbortMode堆棧
orr r1,r0,#ABORTMODE|NOINT
msr cpsr_cxsf,r1 ;AbortMode
ldr sp,=AbortStack
;IRQMode堆棧
orr r1,r0,#IRQMODE|NOINT
msr cpsr_cxsf,r1 ;IRQMode
ldr sp,=IRQStack
;FIQMode堆棧
orr r1,r0,#FIQMODE|NOINT
msr cpsr_cxsf,r1 ;FIQMode
ldr sp,=FIQStack
;SVCMode堆棧
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 wont be valid if the current mode is not SVC mode.
LTORG ;聲明一個(gè)數(shù)據(jù)緩沖池的開始
SMRDATA DA
; 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));BWSCON=0x2211D110
DCD ((B0_Tacs<<13)+(B0_Tcos<<11)+(B0_Tacc<<8)+(B0_Tcoh<<6)+(B0_Tah<<4)+(B0_Tacp<<2)+(B0_PMC)) ;GCS0 BANK0CON=0x0700
DCD ((B1_Tacs<<13)+(B1_Tcos<<11)+(B1_Tacc<<8)+(B1_Tcoh<<6)+(B1_Tah<<4)+(B1_Tacp<<2)+(B1_PMC)) ;GCS1 BANK1CON=0x7FFC
DCD ((B2_Tacs<<13)+(B2_Tcos<<11)+(B2_Tacc<<8)+(B2_Tcoh<<6)+(B2_Tah<<4)+(B2_Tacp<<2)+(B2_PMC)) ;GCS2 BANKCON2=0x0700
DCD 0x1f7c;((B3_Tacs<<13)+(B3_Tcos<<11)+(B3_Tacc<<8)+(B3_Tcoh<<6)+(B3_Tah<<4)+(B3_Tacp<<2)+(B3_PMC)) ;GCS3 BANKCON3=0x0700
DCD ((B4_Tacs<<13)+(B4_Tcos<<11)+(B4_Tacc<<8)+(B4_Tcoh<<6)+(B4_Tah<<4)+(B4_Tacp<<2)+(B4_PMC)) ;GCS4 BANKCON4=0x0700
DCD ((B5_Tacs<<13)+(B5_Tcos<<11)+(B5_Tacc<<8)+(B5_Tcoh<<6)+(B5_Tah<<4)+(B5_Tacp<<2)+(B5_PMC)) ;GCS5 BANKCON5=0x0700
DCD ((B6_MT<<15)+(B6_Trcd<<2)+(B6_SCAN)) ;GCS6 BANKCON6=0x18005
DCD ((B7_MT<<15)+(B7_Trcd<<2)+(B7_SCAN)) ;GCS7 BANKCON7=0x18005
DCD ((REFEN<<23)+(TREFMD<<22)+(Trp<<20)+(Trc<<18)+(Tchr<<16)+REFCNT) ;REFRESH=0x008E0459
DCD 0x32 ;SCLK power saving mode, BANKSIZE 128M/128M ;BANKSIZE=0x32
DCD 0x30 ;MRSR6 CL=3clk ;MRSRB6=0x30
DCD 0x30 ;MRSR7 ;MRSRB7=0x30
BaseOfROM DCD |Image$$RO$$Base|
TopOfROM DCD |Image$$RO$$Limit|
BaseOfBSS DCD |Image$$RW$$Base|
BaseOfZero DCD |Image$$ZI$$Base|
EndOfBSS DCD |Image$$ZI$$Limit|
ALIGN ;通過添加補(bǔ)丁字節(jié)使當(dāng)前位置滿足一定的對(duì)齊方式
;可讀寫的數(shù)據(jù)段
AREA RamData, DA
;^=MAP:定義一個(gè)結(jié)構(gòu)化的內(nèi)存表(storage map)的首地址,地址為0x33ff8000
^ _ISR_STARTADDRESS ;0x33ff8000
HandleReset # 4 ;#--Field:定義一個(gè)結(jié)構(gòu)化內(nèi)存表中的數(shù)據(jù)域,該域?yàn)?個(gè)字節(jié)
HandleUndef # 4
HandleSWI # 4
HandlePabort # 4
HandleDabort # 4
HandleReserved # 4
HandleIRQ # 4
HandleFIQ # 4
;Dont 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
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