commit
a2bd42c81a
|
@ -18,11 +18,10 @@
|
|||
.equ F_Bit, 0x40 @ when F bit is set, FIQ is disabled
|
||||
|
||||
.equ UND_Stack_Size, 0x00000000
|
||||
.equ SVC_Stack_Size, 0x00000100
|
||||
.equ SVC_Stack_Size, 0x00000000
|
||||
.equ ABT_Stack_Size, 0x00000000
|
||||
.equ FIQ_Stack_Size, 0x00000000
|
||||
.equ IRQ_Stack_Size, 0x00000100
|
||||
.equ USR_Stack_Size, 0x00000100
|
||||
.equ FIQ_Stack_Size, 0x00001000
|
||||
.equ IRQ_Stack_Size, 0x00001000
|
||||
|
||||
.section .bss.noinit
|
||||
/* stack */
|
||||
|
@ -31,7 +30,7 @@
|
|||
|
||||
stack_start:
|
||||
.rept (UND_Stack_Size + SVC_Stack_Size + ABT_Stack_Size + FIQ_Stack_Size + IRQ_Stack_Size)
|
||||
.long 0
|
||||
.byte 0
|
||||
.endr
|
||||
stack_top:
|
||||
|
||||
|
@ -63,6 +62,9 @@ _reset:
|
|||
@ Initialize Stack Pointers
|
||||
ldr r0, =stack_top
|
||||
|
||||
@ Set the startup stack for svc
|
||||
mov sp, r0
|
||||
|
||||
@ Enter Undefined Instruction Mode and set its Stack Pointer
|
||||
msr cpsr_c, #Mode_UND|I_Bit|F_Bit
|
||||
mov sp, r0
|
||||
|
@ -83,14 +85,8 @@ _reset:
|
|||
mov sp, r0
|
||||
sub r0, r0, #IRQ_Stack_Size
|
||||
|
||||
@ Enter Supervisor Mode and set its Stack Pointer
|
||||
@ Switch back to SVC
|
||||
msr cpsr_c, #Mode_SVC|I_Bit|F_Bit
|
||||
mov sp, r0
|
||||
sub r0, r0, #SVC_Stack_Size
|
||||
|
||||
@ Enter User Mode and set its Stack Pointer
|
||||
mov sp, r0
|
||||
sub sl, sp, #USR_Stack_Size
|
||||
|
||||
bl next1
|
||||
next1:
|
||||
|
|
Loading…
Reference in New Issue