;============================================================================================== ; star_rvds.s for Keil MDK 4.10 ; ; SEP4020 start up code ; ; Change Logs: ; Date Author Notes ; 2010-03-17 zchong ;============================================================================================= ; PMU_PLTR EQU 0x10001000 ; PLL的稳定过渡时间 PMU_PMCR EQU 0x10001004 ; 系统主时钟PLL的控制寄存器 PMU_PUCR EQU 0x10001008 ; USB时钟PLL的控制寄存器 PMU_PCSR EQU 0x1000100C ; 内部模块时钟源供给的控制寄存器 PMU_PDSLOW EQU 0x10001010 ; SLOW状态下时钟的分频因子 PMU_PMDR EQU 0x10001014 ; 芯片工作模式寄存器 PMU_RCTR EQU 0x10001018 ; Reset控制寄存器 PMU_CLRWAKUP EQU 0x1000101C ; WakeUp清除寄存器 RTC_CTR EQU 0x1000200C ; RTC控制寄存器 INTC_IER EQU 0x10000000 ; IRQ中断允许寄存器 INTC_IMR EQU 0x10000008 ; IRQ中断屏蔽寄存器 INTC_IFSR EQU 0x10000030 ; IRQ中断最终状态寄存器 INTC_FIER EQU 0x100000C0 ; FIQ中断允许寄存器 INTC_FIMR EQU 0x100000C4 ; FIQ中断屏蔽寄存器 EMI_CSACONF EQU 0x11000000 ; CSA参数配置寄存器 EMI_CSECONF EQU 0x11000010 ; CSE参数配置寄存器 EMI_CSFCONF EQU 0x11000014 ; CSF参数配置寄存器 EMI_SDCONF1 EQU 0x11000018 ; SDRAM时序配置寄存器1 EMI_SDCONF2 EQU 0x1100001C ; SDRAM时序配置寄存器2, SDRAM初始化用到的配置信息 EMI_REMAPCONF EQU 0x11000020 ; 片选空间及地址映射REMAP配置寄存器 Mode_USR EQU 0x10 Mode_FIQ EQU 0x11 Mode_IRQ EQU 0x12 Mode_SVC EQU 0x13 Mode_ABT EQU 0x17 Mode_UND EQU 0x1B Mode_SYS EQU 0x1F I_Bit EQU 0x80 ; when I bit is set, IRQ is disabled F_Bit EQU 0x40 ; when F bit is set, FIQ is disabled NOINT EQU 0xc0 MASK_MODE EQU 0x0000003F MODE_SVC32 EQU 0x00000013 ; Internal Memory Base Addresses FLASH_BASE EQU 0x20000000 RAM_BASE EQU 0x04000000 ; Stack UND_Stack_Size EQU 0x00000000 SVC_Stack_Size EQU 0x00000400 ABT_Stack_Size EQU 0x00000000 FIQ_Stack_Size EQU 0x00000000 IRQ_Stack_Size EQU 0x00000100 USR_Stack_Size EQU 0x00000000 ISR_Stack_Size EQU (UND_Stack_Size + SVC_Stack_Size + ABT_Stack_Size + \ FIQ_Stack_Size + IRQ_Stack_Size) AREA STACK, NOINIT, READWRITE, ALIGN=3 Stack_Mem SPACE USR_Stack_Size __initial_sp SPACE ISR_Stack_Size Stack_Top ; Heap Heap_Size EQU 0x00000000 AREA HEAP, NOINIT, READWRITE, ALIGN=3 __heap_base Heap_Mem SPACE Heap_Size __heap_limit PRESERVE8 ; Area Definition and Entry Point ; Startup Code must be linked first at Address at which it expects to run. AREA RESET, CODE, READONLY ARM ; Exception Vectors ; Mapped to Address 0. ; Absolute addressing mode must be used. ; Dummy Handlers are implemented as infinite loops which can be modified. Vectors LDR PC,Reset_Addr LDR PC,Undef_Addr LDR PC,SWI_Addr LDR PC,PAbt_Addr LDR PC,DAbt_Addr NOP ; Reserved Vector LDR PC,IRQ_Addr LDR PC,FIQ_Addr Reset_Addr DCD Reset_Handler Undef_Addr DCD Undef_Handler SWI_Addr DCD SWI_Handler PAbt_Addr DCD PAbt_Handler DAbt_Addr DCD DAbt_Handler DCD 0 ; Reserved Address IRQ_Addr DCD IRQ_Handler FIQ_Addr DCD FIQ_Handler Undef_Handler B Undef_Handler SWI_Handler B SWI_Handler PAbt_Handler B PAbt_Handler DAbt_Handler B DAbt_Handler FIQ_Handler B FIQ_Handler ; Reset Handler EXPORT Reset_Handler Reset_Handler ;**************************************************************** ;* 关闭看门狗 ;**************************************************************** LDR R0,=RTC_CTR LDR R1,=0x0 STR R1,[R0] ;**************************************************************** ;* 关中断 ;**************************************************************** MRS R0, CPSR BIC R0, R0, #MASK_MODE ORR R0, R0, #MODE_SVC32 ORR R0, R0, #I_Bit ORR R0, R0, #F_Bit MSR CPSR_c, r0 LDR R0,=INTC_IER LDR R1,=0x0 STR R1,[R0] LDR R0,=INTC_IMR LDR R1,=0xFFFFFFFF STR R1,[R0] LDR R0,=INTC_FIER LDR R1,=0x0 STR R1,[R0] LDR R0,=INTC_FIMR LDR R1,=0x0F STR R1,[R0] ;**************************************************************** ;* 初始化PMU模块, 配置系统时钟 ;**************************************************************** LDR R4, =PMU_PCSR ; 打开所有模块时钟 LDR R5, =0x0001ffff STR R5, [ R4 ] LDR R4, =PMU_PLTR ; 配置PLL稳定过度时间为保守值50us*100M. LDR R5, =0x00fa00fa STR R5, [ R4 ] LDR R4, =PMU_PMDR ; 由SLOW模式进入NORMAL模式 LDR R5, =0x00000001 STR R5, [ R4 ] LDR R4, =PMU_PMCR ; 配置系统时钟为72MHz 2*Fin*9=2*4*9=72MHz LDR R5, =0x00004009 ; MFCN 0->1 trigger PLL to reconfigure event when mode isn''t SLOW STR R5, [ R4 ] LDR R4, =PMU_PMCR ; LDR R5, =0x0000c009 STR R5, [ R4 ] ;**************************************************************** ;* 初始化EMI ;**************************************************************** ; LDR R4, =EMI_CSACONF ; CSA片选时序参数配置 ; LDR R5, =0x08a6a6a1 ; STR R5, [ R4 ] ; LDR R4, =EMI_CSECONF ; CSE片选时序参数配置,最保守配置 ; LDR R5, =0x8cfffff1 ; STR R5, [ R4 ] ; LDR R4, =EMI_SDCONF1 ; SDRAM参数配置1 ; LDR R5, =0x1E104177 ; STR R5, [ R4 ] ; LDR R4, =EMI_SDCONF2 ; SDRAM参数配置2 ; LDR R5, =0x80001860 ; STR R5, [ R4 ] ; Copy Exception Vectors to Internal RAM IF :DEF:RAM_INTVEC ADR R8, Vectors ; Source LDR R9, =RAM_BASE ; Destination LDMIA R8!, {R0-R7} ; Load Vectors STMIA R9!, {R0-R7} ; Store Vectors LDMIA R8!, {R0-R7} ; Load Handler Addresses STMIA R9!, {R0-R7} ; Store Handler Addresses ENDIF ; Remap on-chip RAM to address 0 IF :DEF:REMAP LDR R0, =EMI_REMAPCONF MOV R1, #0x80000000 STR R1, [R0, #0] ; Remap ENDIF ; Setup Stack for each mode LDR R0, =Stack_Top ; Enter Undefined Instruction Mode and set its Stack Pointer MSR CPSR_c, #Mode_UND:OR:I_Bit:OR:F_Bit MOV SP, R0 SUB R0, R0, #UND_Stack_Size ; Enter Abort Mode and set its Stack Pointer MSR CPSR_c, #Mode_ABT:OR:I_Bit:OR:F_Bit MOV SP, R0 SUB R0, R0, #ABT_Stack_Size ; Enter FIQ Mode and set its Stack Pointer MSR CPSR_c, #Mode_FIQ:OR:I_Bit:OR:F_Bit MOV SP, R0 SUB R0, R0, #FIQ_Stack_Size ; Enter IRQ Mode and set its Stack Pointer MSR CPSR_c, #Mode_IRQ:OR:I_Bit:OR:F_Bit MOV SP, R0 SUB R0, R0, #IRQ_Stack_Size ; Enter Supervisor Mode and set its Stack Pointer MSR CPSR_c, #Mode_SVC:OR:I_Bit:OR:F_Bit MOV SP, R0 SUB R0, R0, #SVC_Stack_Size ; Enter User Mode and set its Stack Pointer ; MSR CPSR_c, #Mode_USR IF :DEF:__MICROLIB EXPORT __initial_sp ELSE ; No usr mode stack here. ;MOV SP, R0 ;SUB SL, SP, #USR_Stack_Size ENDIF ; Enter the C code IMPORT __main LDR R0, =__main BX R0 IMPORT rt_interrupt_enter IMPORT rt_interrupt_leave IMPORT rt_thread_switch_interrput_flag IMPORT rt_interrupt_from_thread IMPORT rt_interrupt_to_thread IMPORT rt_hw_trap_irq IMPORT rt_hw_trap_abort IMPORT rt_interrupt_nest Abort_Handler PROC EXPORT Abort_Handler STMFD SP!, {R0-R12,LR} LDR R0, =rt_interrupt_nest LDR R1, [R0] CMP R1, #0 DeadLoop BHI DeadLoop ; Abort happened in irq mode, halt system. BL rt_interrupt_enter BL rt_hw_trap_abort BL rt_interrupt_leave B SWITCH ENDP IRQ_Handler PROC EXPORT IRQ_Handler STMFD SP!, {R0-R12,LR} BL rt_interrupt_enter BL rt_hw_trap_irq BL rt_interrupt_leave ; if rt_thread_switch_interrput_flag set, jump to ; rt_hw_context_switch_interrupt_do and don't return SWITCH LDR R0, =rt_thread_switch_interrput_flag LDR R1, [R0] CMP R1, #1 BEQ rt_hw_context_switch_interrupt_do LDMFD SP!, {R0-R12,LR} SUBS PC, LR, #4 ENDP ; /* ; * void rt_hw_context_switch_interrupt_do(rt_base_t flag) ; */ rt_hw_context_switch_interrupt_do PROC EXPORT rt_hw_context_switch_interrupt_do MOV r1, #0 ; clear flag STR r1, [r0] LDMFD sp!, {r0-r12,lr}; reload saved registers STMFD sp!, {r0-r3} ; save r0-r3 MOV r1, sp ADD sp, sp, #16 ; restore sp SUB r2, lr, #4 ; save old task's pc to r2 MRS r3, spsr ; get cpsr of interrupt thread ; switch to SVC mode and no interrupt MSR cpsr_c, #I_Bit:OR:F_Bit:OR:Mode_SVC STMFD sp!, {r2} ; push old task's pc STMFD sp!, {r4-r12,lr}; push old task's lr,r12-r4 MOV r4, r1 ; Special optimised code below MOV r5, r3 LDMFD r4!, {r0-r3} STMFD sp!, {r0-r3} ; push old task's r3-r0 STMFD sp!, {r5} ; push old task's cpsr MRS r4, spsr STMFD sp!, {r4} ; push old task's spsr LDR r4, =rt_interrupt_from_thread LDR r5, [r4] STR sp, [r5] ; store sp in preempted tasks's TCB LDR r6, =rt_interrupt_to_thread LDR r6, [r6] LDR sp, [r6] ; get new task's stack pointer LDMFD sp!, {r4} ; pop new task's spsr MSR spsr_cxsf, r4 LDMFD sp!, {r4} ; pop new task's psr MSR cpsr_cxsf, r4 LDMFD sp!, {r0-r12,lr,pc} ; pop new task's r0-r12,lr & pc ENDP IF :DEF:__MICROLIB EXPORT __heap_base EXPORT __heap_limit ELSE ; User Initial Stack & Heap AREA |.text|, CODE, READONLY IMPORT __use_two_region_memory EXPORT __user_initial_stackheap __user_initial_stackheap LDR R0, = Heap_Mem LDR R1, = (Stack_Mem + IRQ_Stack_Size) LDR R2, = (Heap_Mem + Heap_Size) LDR R3, = Stack_Mem BX LR ENDIF END