95 lines
2.3 KiB
ArmAsm
95 lines
2.3 KiB
ArmAsm
|
/*
|
||
|
|
* File : context.S
|
||
|
|
* This file is part of RT-Thread RTOS
|
||
|
|
* COPYRIGHT (C) 2006, RT-Thread Development Team
|
||
|
|
*
|
||
|
|
* The license and distribution terms for this file may be
|
||
|
|
* found in the file LICENSE in this distribution or at
|
||
|
|
* http://www.rt-thread.org/license/LICENSE
|
||
|
|
*
|
||
|
|
* Change Logs:
|
||
|
|
* Date Author Notes
|
||
|
|
* 2006-03-13 Bernard first version
|
||
|
|
*/
|
||
|
|
|
||
|
|
#define NOINT 0xc0
|
||
|
|
|
||
|
|
/*
|
||
|
|
* rt_base_t rt_hw_interrupt_disable()/*
|
||
|
|
*/
|
||
|
|
.globl rt_hw_interrupt_disable
|
||
|
|
rt_hw_interrupt_disable:
|
||
|
|
mrs r0, cpsr
|
||
|
|
orr r1, r0, #NOINT
|
||
|
|
msr cpsr_c, r1
|
||
|
|
mov pc, lr
|
||
|
|
|
||
|
|
/*
|
||
|
|
* void rt_hw_interrupt_enable(rt_base_t level)/*
|
||
|
|
*/
|
||
|
|
.globl rt_hw_interrupt_enable
|
||
|
|
rt_hw_interrupt_enable:
|
||
|
|
msr cpsr, r0
|
||
|
|
mov pc, lr
|
||
|
|
|
||
|
|
/*
|
||
|
|
* void rt_hw_context_switch(rt_uint32 from, rt_uint32 to)/*
|
||
|
|
* r0 --> from
|
||
|
|
* r1 --> to
|
||
|
|
*/
|
||
|
|
.globl rt_hw_context_switch
|
||
|
|
rt_hw_context_switch:
|
||
|
|
stmfd sp!, {lr} /* push pc (lr should be pushed in place of PC) */
|
||
|
|
stmfd sp!, {r0-r12, lr} /* push lr & register file */
|
||
|
|
|
||
|
|
mrs r4, cpsr
|
||
|
|
stmfd sp!, {r4} /* push cpsr */
|
||
|
|
mrs r4, spsr
|
||
|
|
stmfd sp!, {r4} /* push spsr */
|
||
|
|
|
||
|
|
str sp, [r0] /* store sp in preempted tasks TCB */
|
||
|
|
ldr sp, [r1] /* get new task stack pointer */
|
||
|
|
|
||
|
|
ldmfd sp!, {r4} /* pop new task spsr */
|
||
|
|
msr spsr_cxsf, r4
|
||
|
|
ldmfd sp!, {r4} /* pop new task cpsr */
|
||
|
|
msr cpsr_cxsf, r4
|
||
|
|
|
||
|
|
ldmfd sp!, {r0-r12, lr, pc} /* pop new task r0-r12, lr & pc */
|
||
|
|
|
||
|
|
/*
|
||
|
|
* void rt_hw_context_switch_to(rt_uint32 to)/*
|
||
|
|
* r0 --> to
|
||
|
|
*/
|
||
|
|
.globl rt_hw_context_switch_to
|
||
|
|
rt_hw_context_switch_to:
|
||
|
|
ldr sp, [r0] /* get new task stack pointer */
|
||
|
|
|
||
|
|
ldmfd sp!, {r4} /* pop new task spsr */
|
||
|
|
msr spsr_cxsf, r4
|
||
|
|
ldmfd sp!, {r4} /* pop new task cpsr */
|
||
|
|
msr cpsr_cxsf, r4
|
||
|
|
|
||
|
|
ldmfd sp!, {r0-r12, lr, pc} /* pop new task r0-r12, lr & pc */
|
||
|
|
|
||
|
|
/*
|
||
|
|
* void rt_hw_context_switch_interrupt(rt_uint32 from, rt_uint32 to)/*
|
||
|
|
*/
|
||
|
|
.globl rt_thread_switch_interrput_flag
|
||
|
|
.globl rt_interrupt_from_thread
|
||
|
|
.globl rt_interrupt_to_thread
|
||
|
|
.globl rt_hw_context_switch_interrupt
|
||
|
|
rt_hw_context_switch_interrupt:
|
||
|
|
ldr r2, =rt_thread_switch_interrput_flag
|
||
|
|
ldr r3, [r2]
|
||
|
|
cmp r3, #1
|
||
|
|
beq _reswitch
|
||
|
|
mov r3, #1 /* set rt_thread_switch_interrput_flag to 1 */
|
||
|
|
str r3, [r2]
|
||
|
|
ldr r2, =rt_interrupt_from_thread /* set rt_interrupt_from_thread */
|
||
|
|
str r0, [r2]
|
||
|
|
_reswitch:
|
||
|
|
ldr r2, =rt_interrupt_to_thread /* set rt_interrupt_to_thread */
|
||
|
|
str r1, [r2]
|
||
|
|
mov pc, lr
|