nrf51822_写个u-boot

Sipenlin 2015-03-31 05:50:28

原本的起始代码是从0x00000000,开始的；想写个u-boot改变代码的起始地址。
比如我将代码烧到Flash0x00002000处，我要正常启动，写这个u-boot遇到的问题是，无法跳转到相应的地址。
51822是M0的核，没有MVIC。
有什么办法可以做到，跳转？

附启动代码：

Stack_Size EQU 2048
AREA STACK, NOINIT, READWRITE, ALIGN=3
Stack_Mem SPACE Stack_Size
__initial_sp

Heap_Size EQU 2048

AREA HEAP, NOINIT, READWRITE, ALIGN=3
__heap_base
Heap_Mem SPACE Heap_Size
__heap_limit

PRESERVE8
THUMB

; Vector Table Mapped to Address 0 at Reset

AREA RESET, DATA, READONLY
EXPORT __Vectors
EXPORT __Vectors_End
EXPORT __Vectors_Size

__Vectors DCD __initial_sp ; Top of Stack
DCD Reset_Handler ; Reset Handler
DCD NMI_Handler ; NMI Handler
DCD HardFault_Handler ; Hard Fault Handler
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD SVC_Handler ; SVCall Handler
DCD 0 ; Reserved
DCD 0 ; Reserved
DCD PendSV_Handler ; PendSV Handler
DCD SysTick_Handler ; SysTick Handler

; External Interrupts
DCD POWER_CLOCK_IRQHandler ;POWER_CLOCK
DCD RADIO_IRQHandler ;RADIO
DCD UART0_IRQHandler ;UART0
DCD SPI0_TWI0_IRQHandler ;SPI0_TWI0
DCD SPI1_TWI1_IRQHandler ;SPI1_TWI1
DCD 0 ;Reserved
DCD GPIOTE_IRQHandler ;GPIOTE
DCD ADC_IRQHandler ;ADC
DCD TIMER0_IRQHandler ;TIMER0
DCD TIMER1_IRQHandler ;TIMER1
DCD TIMER2_IRQHandler ;TIMER2
DCD RTC0_IRQHandler ;RTC0
DCD TEMP_IRQHandler ;TEMP
DCD RNG_IRQHandler ;RNG
DCD ECB_IRQHandler ;ECB
DCD CCM_AAR_IRQHandler ;CCM_AAR
DCD WDT_IRQHandler ;WDT
DCD RTC1_IRQHandler ;RTC1
DCD QDEC_IRQHandler ;QDEC
DCD LPCOMP_IRQHandler ;LPCOMP
DCD SWI0_IRQHandler ;SWI0
DCD SWI1_IRQHandler ;SWI1
DCD SWI2_IRQHandler ;SWI2
DCD SWI3_IRQHandler ;SWI3
DCD SWI4_IRQHandler ;SWI4
DCD SWI5_IRQHandler ;SWI5
DCD 0 ;Reserved
DCD 0 ;Reserved
DCD 0 ;Reserved
DCD 0 ;Reserved
DCD 0 ;Reserved
DCD 0 ;Reserved
DCD BOOTLOADER_Handler;

__Vectors_End

__Vectors_Size EQU __Vectors_End - __Vectors

AREA |.text|, CODE, READONLY

; Reset Handler

NRF_POWER_RAMON_ADDRESS EQU 0x40000524 ; NRF_POWER->RAMON address
NRF_POWER_RAMONB_ADDRESS EQU 0x40000554 ; NRF_POWER->RAMONB address
NRF_POWER_RAMONx_RAMxON_ONMODE_Msk EQU 0x3 ; All RAM blocks on in onmode bit mask

;CHANGE_CODE EQU 0x00004000 ;

Reset_Handler PROC
EXPORT Reset_Handler [WEAK]
IMPORT SystemInit
IMPORT __main
IMPORT BOOTLOADER_CODE

MOVS R1, #NRF_POWER_RAMONx_RAMxON_ONMODE_Msk

LDR R0, =NRF_POWER_RAMON_ADDRESS
LDR R2, [R0]
ORRS R2, R2, R1
STR R2, [R0]

LDR R0, =NRF_POWER_RAMONB_ADDRESS
LDR R2, [R0]
ORRS R2, R2, R1
STR R2, [R0]

LDR R0, =SystemInit
BLX R0

LDR R0, =BOOTLOADER_CODE ;这里判断是否有代码更新，如果有则移植新代码，无则跳过。
BLX R0

LDR R4, =0x000010EA ;这里判断是否有代码更新，如果有则移植新代码，无则跳过。
;ldr sp,=0x000010EA
BLX R4

LDR R0, =__main
BLX R0

ENDP
;LDR R0, =SystemInit
;BLX R0
;LDR R0, =__main
;BX R0

; Dummy Exception Handlers (infinite loops which can be modified)

NMI_Handler PROC
EXPORT NMI_Handler [WEAK]
B .
ENDP
HardFault_Handler\
PROC
EXPORT HardFault_Handler [WEAK]
B .
ENDP
SVC_Handler PROC
EXPORT SVC_Handler [WEAK]
B .
ENDP
PendSV_Handler PROC
EXPORT PendSV_Handler [WEAK]
B .
ENDP
SysTick_Handler PROC
EXPORT SysTick_Handler [WEAK]
B .
ENDP

Default_Handler PROC

EXPORT POWER_CLOCK_IRQHandler [WEAK]
EXPORT RADIO_IRQHandler [WEAK]
EXPORT UART0_IRQHandler [WEAK]
EXPORT SPI0_TWI0_IRQHandler [WEAK]
EXPORT SPI1_TWI1_IRQHandler [WEAK]
EXPORT GPIOTE_IRQHandler [WEAK]
EXPORT ADC_IRQHandler [WEAK]
EXPORT TIMER0_IRQHandler [WEAK]
EXPORT TIMER1_IRQHandler [WEAK]
EXPORT TIMER2_IRQHandler [WEAK]
EXPORT RTC0_IRQHandler [WEAK]
EXPORT TEMP_IRQHandler [WEAK]
EXPORT RNG_IRQHandler [WEAK]
EXPORT ECB_IRQHandler [WEAK]
EXPORT CCM_AAR_IRQHandler [WEAK]
EXPORT WDT_IRQHandler [WEAK]
EXPORT RTC1_IRQHandler [WEAK]
EXPORT QDEC_IRQHandler [WEAK]
EXPORT LPCOMP_IRQHandler [WEAK]
EXPORT SWI0_IRQHandler [WEAK]
EXPORT SWI1_IRQHandler [WEAK]
EXPORT SWI2_IRQHandler [WEAK]
EXPORT SWI3_IRQHandler [WEAK]
EXPORT SWI4_IRQHandler [WEAK]
EXPORT SWI5_IRQHandler [WEAK]
POWER_CLOCK_IRQHandler
RADIO_IRQHandler
UART0_IRQHandler
SPI0_TWI0_IRQHandler
SPI1_TWI1_IRQHandler
GPIOTE_IRQHandler
ADC_IRQHandler
TIMER0_IRQHandler
TIMER1_IRQHandler
TIMER2_IRQHandler
RTC0_IRQHandler
TEMP_IRQHandler
RNG_IRQHandler
ECB_IRQHandler
CCM_AAR_IRQHandler
WDT_IRQHandler
RTC1_IRQHandler
QDEC_IRQHandler
LPCOMP_IRQHandler
SWI0_IRQHandler
SWI1_IRQHandler
SWI2_IRQHandler
SWI3_IRQHandler
SWI4_IRQHandler
SWI5_IRQHandler

B .
ENDP
ALIGN

; User Initial Stack & Heap

IF :DEF:__MICROLIB

EXPORT __initial_sp
EXPORT __heap_base
EXPORT __heap_limit

ELSE

IMPORT __use_two_region_memory
EXPORT __user_initial_stackheap
__user_initial_stackheap

LDR R0, = Heap_Mem
LDR R1, = (Stack_Mem + Stack_Size)
LDR R2, = (Heap_Mem + Heap_Size)
LDR R3, = Stack_Mem
BX LR

ALIGN

ENDIF

END

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