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;/*
; * Copyright (c) 2006-2022, RT-Thread Development Team
; *
; * SPDX-License-Identifier: Apache-2.0
; *
; * Change Logs:
; * Date Author Notes
; * 2009-01-20 Bernard first version
; * 2011-07-22 Bernard added thumb mode porting
; * 2013-05-24 Grissiom port to CCS
; * 2013-05-26 Grissiom optimize for ARMv7
; */
.text
.arm
.ref rt_thread_switch_interrupt_flag
.ref rt_interrupt_from_thread
.ref rt_interrupt_to_thread
.ref rt_interrupt_enter
.ref rt_interrupt_leave
.ref rt_hw_trap_irq
;/*
; * rt_base_t rt_hw_interrupt_disable();
; */
.def rt_hw_interrupt_disable
.asmfunc
rt_hw_interrupt_disable
MRS r0, cpsr
CPSID IF
BX lr
.endasmfunc
;/*
; * void rt_hw_interrupt_enable(rt_base_t level);
; */
.def rt_hw_interrupt_enable
.asmfunc
rt_hw_interrupt_enable
MSR cpsr_c, r0
BX lr
.endasmfunc
;/*
; * void rt_hw_context_switch(rt_uint32 from, rt_uint32 to);
; * r0 --> from
; * r1 --> to
; */
.def rt_hw_context_switch
.asmfunc
rt_hw_context_switch
STMDB sp!, {lr} ; push pc (lr should be pushed in place of PC)
STMDB sp!, {r0-r12, lr} ; push lr & register file
MRS r4, cpsr
TST lr, #0x01
ORRNE r4, r4, #0x20 ; it's thumb code
STMDB sp!, {r4} ; push cpsr
.if (__TI_VFP_SUPPORT__)
VMRS r4, fpexc
TST r4, #0x40000000
BEQ __no_vfp_frame1
VSTMDB sp!, {d0-d15}
VMRS r5, fpscr
; TODO: add support for Common VFPv3.
; Save registers like FPINST, FPINST2
STMDB sp!, {r5}
__no_vfp_frame1
STMDB sp!, {r4}
.endif
STR sp, [r0] ; store sp in preempted tasks TCB
LDR sp, [r1] ; get new task stack pointer
.if (__TI_VFP_SUPPORT__)
LDMIA sp!, {r0} ; get fpexc
VMSR fpexc, r0 ; restore fpexc
TST r0, #0x40000000
BEQ __no_vfp_frame2
LDMIA sp!, {r1} ; get fpscr
VMSR fpscr, r1
VLDMIA sp!, {d0-d15}
__no_vfp_frame2
.endif
LDMIA sp!, {r4} ; pop new task cpsr to spsr
MSR spsr_cxsf, r4
LDMIA sp!, {r0-r12, lr, pc}^ ; pop new task r0-r12, lr & pc, copy spsr to cpsr
.endasmfunc
;/*
; * void rt_hw_context_switch_to(rt_uint32 to);
; * r0 --> to
; */
.def rt_hw_context_switch_to
.asmfunc
rt_hw_context_switch_to
LDR sp, [r0] ; get new task stack pointer
.if (__TI_VFP_SUPPORT__)
LDMIA sp!, {r0} ; get fpexc
VMSR fpexc, r0
TST r0, #0x40000000
BEQ __no_vfp_frame_to
LDMIA sp!, {r1} ; get fpscr
VMSR fpscr, r1
VLDMIA sp!, {d0-d15}
__no_vfp_frame_to
.endif
LDMIA sp!, {r4} ; pop new task cpsr to spsr
MSR spsr_cxsf, r4
LDMIA sp!, {r0-r12, lr, pc}^ ; pop new task r0-r12, lr & pc, copy spsr to cpsr
.endasmfunc
;/*
; * void rt_hw_context_switch_interrupt(rt_uint32 from, rt_uint32 to);
; */
.def rt_hw_context_switch_interrupt
.asmfunc
rt_hw_context_switch_interrupt
LDR r2, pintflag
LDR r3, [r2]
CMP r3, #1
BEQ _reswitch
MOV r3, #1 ; set rt_thread_switch_interrupt_flag to 1
STR r3, [r2]
LDR r2, pfromthread ; set rt_interrupt_from_thread
STR r0, [r2]
_reswitch
LDR r2, ptothread ; set rt_interrupt_to_thread
STR r1, [r2]
BX lr
.endasmfunc
.def IRQ_Handler
IRQ_Handler
STMDB sp!, {r0-r12,lr}
.if (__TI_VFP_SUPPORT__)
VMRS r0, fpexc
TST r0, #0x40000000
BEQ __no_vfp_frame_str_irq
VSTMDB sp!, {d0-d15}
VMRS r1, fpscr
; TODO: add support for Common VFPv3.
; Save registers like FPINST, FPINST2
STMDB sp!, {r1}
__no_vfp_frame_str_irq
STMDB sp!, {r0}
.endif
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, pintflag
LDR r1, [r0]
CMP r1, #1
BEQ rt_hw_context_switch_interrupt_do
.if (__TI_VFP_SUPPORT__)
LDMIA sp!, {r0} ; get fpexc
VMSR fpexc, r0
TST r0, #0x40000000
BEQ __no_vfp_frame_ldr_irq
LDMIA sp!, {r1} ; get fpscr
VMSR fpscr, r1
VLDMIA sp!, {d0-d15}
__no_vfp_frame_ldr_irq
.endif
LDMIA sp!, {r0-r12,lr}
SUBS pc, lr, #4
; /*
; * void rt_hw_context_switch_interrupt_do(rt_base_t flag)
; */
.def rt_hw_context_switch_interrupt_do
rt_hw_context_switch_interrupt_do
MOV r1, #0 ; clear flag
STR r1, [r0]
.if (__TI_VFP_SUPPORT__)
LDMIA sp!, {r0} ; get fpexc
VMSR fpexc, r0
TST r0, #0x40000000
BEQ __no_vfp_frame_do1
LDMIA sp!, {r1} ; get fpscr
VMSR fpscr, r1
VLDMIA sp!, {d0-d15}
__no_vfp_frame_do1
.endif
LDMIA sp!, {r0-r12,lr} ; reload saved registers
STMDB sp, {r0-r3} ; save r0-r3. We will restore r0-r3 in the SVC
; mode so there is no need to update SP.
SUB r1, sp, #16 ; save the right SP value in r1, so we could restore r0-r3.
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
CPSID IF, #0x13
STMDB sp!, {r2} ; push old task's pc
STMDB sp!, {r4-r12,lr} ; push old task's lr,r12-r4
LDMIA r1!, {r4-r7} ; restore r0-r3 of the interrupted thread
STMDB sp!, {r4-r7} ; push old task's r3-r0. We don't need to push/pop them to
; r0-r3 because we just want to transfer the data and don't
; use them here.
STMDB sp!, {r3} ; push old task's cpsr
.if (__TI_VFP_SUPPORT__)
VMRS r0, fpexc
TST r0, #0x40000000
BEQ __no_vfp_frame_do2
VSTMDB sp!, {d0-d15}
VMRS r1, fpscr
; TODO: add support for Common VFPv3.
; Save registers like FPINST, FPINST2
STMDB sp!, {r1}
__no_vfp_frame_do2
STMDB sp!, {r0}
.endif
LDR r4, pfromthread
LDR r5, [r4]
STR sp, [r5] ; store sp in preempted tasks's TCB
LDR r6, ptothread
LDR r6, [r6]
LDR sp, [r6] ; get new task's stack pointer
.if (__TI_VFP_SUPPORT__)
LDMIA sp!, {r0} ; get fpexc
VMSR fpexc, r0
TST r0, #0x40000000
BEQ __no_vfp_frame_do3
LDMIA sp!, {r1} ; get fpscr
VMSR fpscr, r1
VLDMIA sp!, {d0-d15}
__no_vfp_frame_do3
.endif
LDMIA sp!, {r4} ; pop new task's cpsr to spsr
MSR spsr_cxsf, r4
LDMIA sp!, {r0-r12,lr,pc}^ ; pop new task's r0-r12,lr & pc, copy spsr to cpsr
pintflag .word rt_thread_switch_interrupt_flag
pfromthread .word rt_interrupt_from_thread
ptothread .word rt_interrupt_to_thread
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