smart-green-house/rtt-uart-nb/rt-thread/libcpu/arm/arm926/start_iar.S

279 lines
7.6 KiB
ArmAsm
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

;/*
; * Copyright (c) 2006-2018, RT-Thread Development Team
; *
; * SPDX-License-Identifier: Apache-2.0
; *
; * Change Logs:
; * Date Author Notes
; * 2011-01-13 weety first version
; * 2015-04-15 ArdaFu Split from AT91SAM9260 BSP
; * 2015-04-21 ArdaFu Remove remap code. Using mmu to map vector table
; * 2015-06-04 aozima Align stack address to 8 byte.
; */
#include "rt_low_level_init.h"
#define S_FRAME_SIZE (18*4) ;72
;#define S_SPSR (17*4) ;SPSR
;#define S_CPSR (16*4) ;CPSR
#define S_PC (15*4) ;R15
;#define S_LR (14*4) ;R14
;#define S_SP (13*4) ;R13
;#define S_IP (12*4) ;R12
;#define S_FP (11*4) ;R11
;#define S_R10 (10*4)
;#define S_R9 (9*4)
;#define S_R8 (8*4)
;#define S_R7 (7*4)
;#define S_R6 (6*4)
;#define S_R5 (5*4)
;#define S_R4 (4*4)
;#define S_R3 (3*4)
;#define S_R2 (2*4)
;#define S_R1 (1*4)
;#define S_R0 (0*4)
#define MODE_SYS 0x1F
#define MODE_FIQ 0x11
#define MODE_IRQ 0x12
#define MODE_SVC 0x13
#define MODE_ABT 0x17
#define MODE_UND 0x1B
#define MODEMASK 0x1F
#define NOINT 0xC0
;----------------------- Stack and Heap Definitions ----------------------------
MODULE ?cstartup
SECTION .noinit:DATA:NOROOT(3)
DATA
ALIGNRAM 3
DS8 UND_STK_SIZE
PUBLIC UND_STACK_START
UND_STACK_START:
ALIGNRAM 3
DS8 ABT_STK_SIZE
PUBLIC ABT_STACK_START
ABT_STACK_START:
ALIGNRAM 3
DS8 FIQ_STK_SIZE
PUBLIC FIQ_STACK_START
FIQ_STACK_START:
ALIGNRAM 3
DS8 IRQ_STK_SIZE
PUBLIC IRQ_STACK_START
IRQ_STACK_START:
ALIGNRAM 3
DS8 SYS_STK_SIZE
PUBLIC SYS_STACK_START
SYS_STACK_START:
ALIGNRAM 3
DS8 SVC_STK_SIZE
PUBLIC SVC_STACK_START
SVC_STACK_START:
;--------------Jump vector table------------------------------------------------
SECTION .intvec:CODE:ROOT(2)
ARM
PUBLIC Entry_Point
Entry_Point:
__iar_init$$done: ; The interrupt vector is not needed
; until after copy initialization is done
LDR PC, vector_reset
LDR PC, vector_undef
LDR PC, vector_swi
LDR PC, vector_pabt
LDR PC, vector_dabt
LDR PC, vector_resv
LDR PC, vector_irq
LDR PC, vector_fiq
vector_reset:
DC32 Reset_Handler
vector_undef:
DC32 Undef_Handler
vector_swi:
DC32 SWI_Handler
vector_pabt:
DC32 PAbt_Handler
vector_dabt:
DC32 DAbt_Handler
vector_resv:
DC32 Resv_Handler
vector_irq:
DC32 IRQ_Handler
vector_fiq:
DC32 FIQ_Handler
;----------------- Reset Handler -----------------------------------------------
EXTERN rt_low_level_init
EXTERN ?main
PUBLIC __iar_program_start
__iar_program_start:
Reset_Handler:
; Set the cpu to SVC32 mode
MRS R0, CPSR
BIC R0, R0, #MODEMASK
ORR R0, R0, #MODE_SVC|NOINT
MSR CPSR_cxsf, R0
; Set CO-Processor
; little-enddisbale I/D Cache MMU, vector table is 0x00000000
MRC P15, 0, R0, C1, C0, 0 ; Read CP15
LDR R1, =0x00003085 ; set clear bits
BIC R0, R0, R1
MCR P15, 0, R0, C1, C0, 0 ; Write CP15
; Call low level init function,
; disable and clear all IRQs, Init MMU, Init interrupt controller, etc.
LDR SP, =SVC_STACK_START
LDR R0, =rt_low_level_init
BLX R0
Setup_Stack:
; Setup Stack for each mode
MRS R0, CPSR
BIC R0, R0, #MODEMASK
ORR R1, R0, #MODE_UND|NOINT
MSR CPSR_cxsf, R1 ; Undef mode
LDR SP, =UND_STACK_START
ORR R1,R0,#MODE_ABT|NOINT
MSR CPSR_cxsf,R1 ; Abort mode
LDR SP, =ABT_STACK_START
ORR R1,R0,#MODE_IRQ|NOINT
MSR CPSR_cxsf,R1 ; IRQ mode
LDR SP, =IRQ_STACK_START
ORR R1,R0,#MODE_FIQ|NOINT
MSR CPSR_cxsf,R1 ; FIQ mode
LDR SP, =FIQ_STACK_START
ORR R1,R0,#MODE_SYS|NOINT
MSR CPSR_cxsf,R1 ; SYS/User mode
LDR SP, =SYS_STACK_START
ORR R1,R0,#MODE_SVC|NOINT
MSR CPSR_cxsf,R1 ; SVC mode
LDR SP, =SVC_STACK_START
; Enter the C code
LDR R0, =?main
BLX R0
;----------------- Exception Handler -------------------------------------------
IMPORT rt_hw_trap_udef
IMPORT rt_hw_trap_swi
IMPORT rt_hw_trap_pabt
IMPORT rt_hw_trap_dabt
IMPORT rt_hw_trap_resv
IMPORT rt_hw_trap_irq
IMPORT rt_hw_trap_fiq
IMPORT rt_interrupt_enter
IMPORT rt_interrupt_leave
IMPORT rt_thread_switch_interrupt_flag
IMPORT rt_interrupt_from_thread
IMPORT rt_interrupt_to_thread
SECTION .text:CODE:ROOT(2)
ARM
Undef_Handler:
SUB SP, SP, #S_FRAME_SIZE
STMIA SP, {R0 - R12} ; Calling R0-R12
ADD R8, SP, #S_PC
STMDB R8, {SP, LR} ; Calling SP, LR
STR LR, [R8, #0] ; Save calling PC
MRS R6, SPSR
STR R6, [R8, #4] ; Save CPSR
STR R0, [R8, #8] ; Save SPSR
MOV R0, SP
BL rt_hw_trap_udef
SWI_Handler:
BL rt_hw_trap_swi
PAbt_Handler:
BL rt_hw_trap_pabt
DAbt_Handler:
SUB SP, SP, #S_FRAME_SIZE
STMIA SP, {R0 - R12} ; Calling R0-R12
ADD R8, SP, #S_PC
STMDB R8, {SP, LR} ; Calling SP, LR
STR LR, [R8, #0] ; Save calling PC
MRS R6, SPSR
STR R6, [R8, #4] ; Save CPSR
STR R0, [R8, #8] ; Save SPSR
MOV R0, SP
BL rt_hw_trap_dabt
Resv_Handler:
BL rt_hw_trap_resv
IRQ_Handler:
STMFD SP!, {R0-R12,LR}
BL rt_interrupt_enter
BL rt_hw_trap_irq
BL rt_interrupt_leave
; If rt_thread_switch_interrupt_flag set,
; jump to rt_hw_context_switch_interrupt_do and don't return
LDR R0, =rt_thread_switch_interrupt_flag
LDR R1, [R0]
CMP R1, #1
BEQ rt_hw_context_switch_interrupt_do
LDMFD SP!, {R0-R12,LR}
SUBS PC, LR, #4
FIQ_Handler:
STMFD SP!, {R0-R7,LR}
BL rt_hw_trap_fiq
LDMFD SP!, {R0-R7,LR}
SUBS PC, LR, #4
;------ void rt_hw_context_switch_interrupt_do(rt_base_t flag) -----------------
rt_hw_context_switch_interrupt_do:
MOV R1, #0 ; Clear flag
STR R1, [R0] ; Save to flag variable
LDMFD SP!, {R0-R12,LR} ; Reload saved registers
STMFD SP, {R0-R2} ; Save R0-R2
SUB R1, SP, #4*3 ; Save old task's SP to R1
SUB R2, LR, #4 ; Save old task's PC to R2
MRS R0, SPSR ; Get CPSR of interrupt thread
MSR CPSR_c, #MODE_SVC|NOINT ; Switch to SVC mode and no interrupt
STMFD SP!, {R2} ; Push old task's PC
STMFD SP!, {R3-R12,LR} ; Push old task's LR,R12-R3
LDMFD R1, {R1-R3}
STMFD SP!, {R1-R3} ; Push old task's R2-R0
STMFD SP!, {R0} ; Push old task's CPSR
LDR R4, =rt_interrupt_from_thread
LDR R5, [R4] ; R5 = stack ptr in old tasks's TCB
STR SP, [R5] ; Store SP in preempted tasks's TCB
LDR R6, =rt_interrupt_to_thread
LDR R6, [R6] ; R6 = stack ptr in new tasks's TCB
LDR SP, [R6] ; Get new task's stack pointer
LDMFD SP!, {R4} ; Pop new task's SPSR
MSR SPSR_cxsf, R4
LDMFD SP!, {R0-R12,LR,PC}^ ; pop new task's R0-R12,LR & PC SPSR to CPSR
END