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author | (no author) <(no author)@6dc7ffe9-61d6-0310-9af1-9938baff3ed1> | 2006-07-25 07:26:19 +0000 |
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committer | (no author) <(no author)@6dc7ffe9-61d6-0310-9af1-9938baff3ed1> | 2006-07-25 07:26:19 +0000 |
commit | 3b8d883129391de3514a1156afe820b31b3ba284 (patch) | |
tree | 1db75e408f3905166833379ce5bcd84ab91dc7de /openpcd/firmware/src/start/Cstartup.S | |
parent | 9164ed9344b1ffd2b6a545afb1dfc7ebe022d315 (diff) |
changed directory structure
git-svn-id: https://svn.openpcd.org:2342/trunk@40 6dc7ffe9-61d6-0310-9af1-9938baff3ed1
Diffstat (limited to 'openpcd/firmware/src/start/Cstartup.S')
-rw-r--r-- | openpcd/firmware/src/start/Cstartup.S | 298 |
1 files changed, 298 insertions, 0 deletions
diff --git a/openpcd/firmware/src/start/Cstartup.S b/openpcd/firmware/src/start/Cstartup.S new file mode 100644 index 0000000..d13dbd8 --- /dev/null +++ b/openpcd/firmware/src/start/Cstartup.S @@ -0,0 +1,298 @@ +/*------------------------------------------------------------------------------ +//*- ATMEL Microcontroller Software Support - ROUSSET - +//*------------------------------------------------------------------------------ +//* The software is delivered "AS IS" without warranty or condition of any +//* kind, either express, implied or statutory. This includes without +//* limitation any warranty or condition with respect to merchantability or +//* fitness for any particular purpose, or against the infringements of +//* intellectual property rights of others. +//*----------------------------------------------------------------------------- +//*- File source : Cstartup.s +//*- Object : Generic CStartup for KEIL and GCC No Use REMAP +//*- Compilation flag : None +//*- +//*- 1.0 18/Oct/04 JPP : Creation +//*- 1.1 21/Feb/05 JPP : Set Interrupt +//*- 1.1 01/Apr/05 JPP : save SPSR +//*-----------------------------------------------------------------------------*/ + + .equ IRQ_Stack_Size, 0x00000060 + +/* #include "AT91SAM7S64_inc.h" */ + + .equ AIC_IVR, (256) + .equ AIC_FVR, (260) + .equ AIC_EOICR, (304) + .equ AT91C_BASE_AIC, (0xFFFFF000) + +#;------------------------------------------------------------------------------ +#;- Section Definition +#;----------------- +#;- Section +#;- .internal_ram_top Top_Stack: used by the cstartup for vector initalisation +#;- management defined by ld and affect from ldscript +#;------------------------------------------------------------------------------ + .section .internal_ram_top + .code 32 + .align 0 + .global Top_Stack +Top_Stack: + +/*------------------------------------------------------------------------------ +*- Area Definition +*------------------------------------------------------------------------------ +* .text is used instead of .section .text so it works with arm-aout too. */ + .section .reset + .text + .global _startup + .func _startup +_startup: +reset: +/*------------------------------------------------------------------------------ +//*- Exception vectors +//*-------------------- +//*- These vectors can be read at address 0 or at RAM address +//*- They ABSOLUTELY requires to be in relative addresssing mode in order to +//*- guarantee a valid jump. For the moment, all are just looping. +//*- If an exception occurs before remap, this would result in an infinite loop. +//*- To ensure if a exeption occurs before start application to infinite loop. +//*------------------------------------------------------------------------------*/ + + B InitReset /* 0x00 Reset handler */ +undefvec: + B undefvec /* 0x04 Undefined Instruction */ +swivec: + B swivec /* 0x08 Software Interrupt */ +pabtvec: + B pabtvec /* 0x0C Prefetch Abort */ +dabtvec: + B dabtvec /* 0x10 Data Abort */ +rsvdvec: + B rsvdvec /* 0x14 reserved */ +irqvec: + B IRQ_Handler_Entry /* 0x18 IRQ */ +fiqvec: /* 0x1c FIQ */ +/*------------------------------------------------------------------------------ +//*- Function : FIQ_Handler_Entry +//*- Treatments : FIQ Controller Interrupt Handler. +//*- Called Functions : AIC_FVR[interrupt] +//*------------------------------------------------------------------------------*/ + +FIQ_Handler_Entry: + +/*- Switch in SVC/User Mode to allow User Stack access for C code */ +/* because the FIQ is not yet acknowledged*/ + +/*- Save and r0 in FIQ_Register */ + mov r9,r0 + ldr r0 , [r8, #AIC_FVR] + msr CPSR_c,#I_BIT | F_BIT | ARM_MODE_SVC + +/*- Save scratch/used registers and LR in User Stack */ + stmfd sp!, { r1-r3, r12, lr} + +/*- Branch to the routine pointed by the AIC_FVR */ + mov r14, pc + bx r0 + +/*- Restore scratch/used registers and LR from User Stack */ + ldmia sp!, { r1-r3, r12, lr} + +/*- Leave Interrupts disabled and switch back in FIQ mode */ + msr CPSR_c, #I_BIT | F_BIT | ARM_MODE_FIQ + +/*- Restore the R0 ARM_MODE_SVC register */ + mov r0,r9 + +/*- Restore the Program Counter using the LR_fiq directly in the PC */ + subs pc,lr,#4 + .align 0 +.RAM_TOP: + .word Top_Stack + +InitReset: +/*------------------------------------------------------------------------------ +/*- Low level Init (PMC, AIC, ? ....) by C function AT91F_LowLevelInit +/*------------------------------------------------------------------------------*/ + .extern AT91F_LowLevelInit +/*- minumum C initialization */ +/*- call AT91F_LowLevelInit( void) */ + + ldr r13,.RAM_TOP /* temporary stack in internal RAM */ +/*--Call Low level init function in ABSOLUTE through the Interworking */ + ldr r0,=AT91F_LowLevelInit + mov lr, pc + bx r0 +/*------------------------------------------------------------------------------ +//*- Stack Sizes Definition +//*------------------------ +//*- Interrupt Stack requires 2 words x 8 priority level x 4 bytes when using +//*- the vectoring. This assume that the IRQ management. +//*- The Interrupt Stack must be adjusted depending on the interrupt handlers. +//*- Fast Interrupt not requires stack If in your application it required you must +//*- be definehere. +//*- The System stack size is not defined and is limited by the free internal +//*- SRAM. +//*------------------------------------------------------------------------------*/ + +/*------------------------------------------------------------------------------ +//*- Top of Stack Definition +//*------------------------- +//*- Interrupt and Supervisor Stack are located at the top of internal memory in +//*- order to speed the exception handling context saving and restoring. +//*- ARM_MODE_SVC (Application, C) Stack is located at the top of the external memory. +//*------------------------------------------------------------------------------*/ + + .EQU IRQ_STACK_SIZE, (3*8*4) + .EQU ARM_MODE_FIQ, 0x11 + .EQU ARM_MODE_IRQ, 0x12 + .EQU ARM_MODE_SVC, 0x13 + + .EQU I_BIT, 0x80 + .EQU F_BIT, 0x40 + +/*------------------------------------------------------------------------------ +//*- Setup the stack for each mode +//*-------------------------------*/ + mov r0,r13 + +/*- Set up Fast Interrupt Mode and set FIQ Mode Stack*/ + msr CPSR_c, #ARM_MODE_FIQ | I_BIT | F_BIT +/*- Init the FIQ register*/ + ldr r8, =AT91C_BASE_AIC + +/*- Set up Interrupt Mode and set IRQ Mode Stack*/ + msr CPSR_c, #ARM_MODE_IRQ | I_BIT | F_BIT + mov r13, r0 /* Init stack IRQ */ + sub r0, r0, #IRQ_Stack_Size +/*- Set up Supervisor Mode and set Supervisor Mode Stack*/ + msr CPSR_c, #ARM_MODE_SVC + mov r13, r0 /* Init stack Sup */ + +/*- Enable interrupt & Set up Supervisor Mode and set Supervisor Mode Stack*/ + +# Relocate .data section (Copy from ROM to RAM) + LDR R1, =_etext + LDR R2, =_data + LDR R3, =_edata +LoopRel: CMP R2, R3 + LDRLO R0, [R1], #4 + STRLO R0, [R2], #4 + BLO LoopRel + +# Clear .bss section (Zero init) + MOV R0, #0 + LDR R1, =__bss_start__ + LDR R2, =__bss_end__ +LoopZI: CMP R1, R2 + STRLO R0, [R1], #4 + BLO LoopZI + + ldr lr,=exit + ldr r0,=main + bx r0 + + .size _startup, . - _startup + .endfunc + +/* "exit" dummy added by mthomas to avoid sbrk write read etc. needed + by the newlib default "exit" */ + .global exit + .func exit +exit: + b . + .size exit, . - exit + .endfunc + +/*------------------------------------------------------------------------------ +//*- Manage exception +//*--------------- +//*- This module The exception must be ensure in ARM mode +//*------------------------------------------------------------------------------ +//*------------------------------------------------------------------------------ +//*- Function : IRQ_Handler_Entry +//*- Treatments : IRQ Controller Interrupt Handler. +//*- Called Functions : AIC_IVR[interrupt] +//*------------------------------------------------------------------------------*/ + .global IRQ_Handler_Entry + .func IRQ_Handler_Entry + +IRQ_Handler_Entry: + +/*- Manage Exception Entry */ +/*- Adjust and save LR_irq in IRQ stack */ + sub lr, lr, #4 + stmfd sp!, {lr} + +/*- Save SPSR need to be saved for nested interrupt */ + mrs r14, SPSR + stmfd sp!, {r14} + +/*- Save and r0 in IRQ stack */ + stmfd sp!, {r0} + +/*- Write in the IVR to support Protect Mode */ +/*- No effect in Normal Mode */ +/*- De-assert the NIRQ and clear the source in Protect Mode */ + ldr r14, =AT91C_BASE_AIC + ldr r0 , [r14, #AIC_IVR] + str r14, [r14, #AIC_IVR] + +/*- Enable Interrupt and Switch in Supervisor Mode */ + msr CPSR_c, #ARM_MODE_SVC + +/*- Save scratch/used registers and LR in User Stack */ + stmfd sp!, { r1-r3, r12, r14} + +/*- Branch to the routine pointed by the AIC_IVR */ + mov r14, pc + bx r0 +/*- Restore scratch/used registers and LR from User Stack*/ + ldmia sp!, { r1-r3, r12, r14} + +/*- Disable Interrupt and switch back in IRQ mode */ + msr CPSR_c, #I_BIT | ARM_MODE_IRQ + +/*- Mark the End of Interrupt on the AIC */ + ldr r14, =AT91C_BASE_AIC + str r14, [r14, #AIC_EOICR] + +/*- Restore SPSR_irq and r0 from IRQ stack */ + ldmia sp!, {r0} + +/*- Restore SPSR_irq and r0 from IRQ stack */ + ldmia sp!, {r14} + msr SPSR_cxsf, r14 + +/*- Restore adjusted LR_irq from IRQ stack directly in the PC */ + ldmia sp!, {pc}^ + + .size IRQ_Handler_Entry, . - IRQ_Handler_Entry + .endfunc +/*--------------------------------------------------------------- +//* ?EXEPTION_VECTOR +//* This module is only linked if needed for closing files. +//*---------------------------------------------------------------*/ + .global AT91F_Default_FIQ_handler + .func AT91F_Default_FIQ_handler +AT91F_Default_FIQ_handler: + b AT91F_Default_FIQ_handler + .size AT91F_Default_FIQ_handler, . - AT91F_Default_FIQ_handler + .endfunc + + .global AT91F_Default_IRQ_handler + .func AT91F_Default_IRQ_handler +AT91F_Default_IRQ_handler: + b AT91F_Default_IRQ_handler + .size AT91F_Default_IRQ_handler, . - AT91F_Default_IRQ_handler + .endfunc + + .global AT91F_Spurious_handler + .func AT91F_Spurious_handler +AT91F_Spurious_handler: + b AT91F_Spurious_handler + .size AT91F_Spurious_handler, . - AT91F_Spurious_handler + .endfunc + + .end + |